This paper reports on the effects of Titanium dioxide (TiO2) thin films which were deposited by sol-gel spin coating technique with different annealing temperatures at 300°C, 400°C and 500°C for a period of 1 hour. The precursor used was 2 ml of Titanium (IV) Butoxide. The research is focusing more on the uniformity of TiO2 thin films. TiO2 films were characterized by structural properties, surface morphological, surface topological and optical properties. For 500°C annealed film, transparent TiO2 thin film were deposited more uniform than the others. The surface morphologies of the TiO2 thin film were observed by a field emission scanning electron microscope (FESEM). The surface topologies and roughness were characterized by an atomic force microscope (AFM). The structural properties were characterized by an X-ray diffractometer (XRD). The optical properties were characterized with an ultraviolet-visible spectrometer (UV-Vis). The results indicated the optical transmittance of TiO2 thin films were elevated with higher annealing temperature.

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Electromagnetic (EM) radiation has been a common concern in most developed and developing countries in terms of the hazard it poses upon human's health and its capabilities of reducing efficiency of electrical and electronic devices in its surrounding. Thus, to overcome this problem, an antenna is playing important role where it should has the function of detecting various hazard of electromagnetic wave. A multi-band microstrip antenna will need to be designed. The antenna design was simulated and the results such as return loss, input impedance, radiation pattern, VSWR, and efficiency were validated and analyzed. Based on the results, it was found that this antenna is able to support modes with resonance of 2.3, 4.5, 4.68 and 5.2 GHz where these resonances are also known as the most high risk EM signal that been exposed by human being in everyday life. The multiband microstrip antenna has been successfully designed by Computer Simulation Technology (CST) microwave studio 2014.

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The purpose of this research is mainly to model a wind turbine with doubly fed induction generator (DFIG) and to investigate its behavior in partial load operation using computer simulation. System behavior analysis and simulation are two particular approaches applied in this research. The wind turbine model is developed whereby the behavior of its main components is described by mathematical model and transformed in simulation model in MATLAB/Simulink. The simulation model is carried out in partial load operation at a wind speed of 9 m/s. The physical quantities including generator speed, torque and electrical power output are measured and evaluated. By using variable speed generator, a wind turbine model with optimum power generation at wind speed between 4 m/s to 13 m/s is created. This research shows that if mathematical models represent the wind turbine accurately, then the proposed model can be used to observe the dynamic behavior of wind turbine precisely, efficiently and inexpensively. The simulation result is expected to be a reference for extending the knowledge of dynamic behavior of wind turbines and optimize the performance of future large-scale wind turbine systems.

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A major disadvantage of energy saving glass using tin oxide (SnO2) thin film is that SnO2 attenuates the mobile signal from passing through it. In order to improve such signal transmission, a frequency selective surface (FSS) structures are designed on SnO2 thin film. In this paper, SnO2 thin film with FSS structure was fabricated using combination of printed circuit board technology and reactive magnetron sputtering deposition. SnO2 thin films were deposited at various rf discharge powers and O2 flow ratios and their physical, electrical and optical properties were analyzed. Experimental results reveal that the transmission of microwave signal improved with the reduction of SnO2 sheet resistance. The grain size of SnO2 thin film significantly influences the value of sheet resistance. The SnO2 sheet resistance was lower at larger grain size. Therefore, a clear correlation was found between SnO2 thin films properties and transmission of microwave signal through SnO2 coated glass with FSS structure. In addition, sufficient amount of O2 gas was required to deposit transparent and functional SnO2 thin film. Optimum condition to deposit SnO2 thin film for energy saving glass with improved microwave transmission has been demonstrated.

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Recently, direct-drive motor for in-wheel electric vehicle application become an interested research topic due to their advantages of directly torque control and elimination of transmission gear system. In conjunction, flux switching machines (FSMs) are among a good candidate to fulfill direct-drive application due to excellent of high starting torque, constant power over wide speed range, low torque ripple and high durability. With all components located on the stator, the machine is extremely robust as compared with interior permanent magnet motor (IPMSM) that conventionally employed in existing EV/HEV. This paper presents the development of actual prototype of outer-rotor hybrid excitation flux switching machine (OR-HEFSM) based on finite element analysis (FEA) and actual prototype analysis (APA). The prototype development procedures are described in details to have excessive visualization and precise prediction results. Through a 3D-Model developed by SOLIDWORKS software, the final design motor has been constructed and fabricated accordingly. Finally, further experimental investigation on final design motor should be implemented to verify the results obtained from simulation works.

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In differential GPS or DGPS, it is generally considered that the ionospheric correction is the same for both reference and unknown target (or mobile or user) receivers. However, it is clear that the ray paths from the satellite to the two receivers will generally traverse the ionosphere at slightly different elevations. Any horizontal ionospheric gradient present would also introduce errors into the DGPS correction. These two effects have been investigated in the present work in order to obtain a more accurate ionospheric correction for DGPS and have been found to be roughly comparable showing that they are both important. To accomplish this, the differential delay between the two paths for different elevations and azimuths has been done using an analytical ray tracing program. By performing ray-tracing calculations with and without a linear horizontal ionosphere gradient, the effects of elevation angle and horizontal gradient have been separated and a ratio of these effects has been determined for different elevations and horizontal ionosphere gradients. Empirical models have been introduced to model these variations based on the ray-tracing results.

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Forecasting price has now become an essential task in the operation of electrical power system. Power producers and customers use short term price forecasts to manage and plan for bidding approaches, and hence increase the utility’s profit and energy efficiency. This paper proposes a novel method of Least Square Support Vector Machine (LSSVM) with Bacterial Foraging Optimization Algorithm (BFOA) to predict daily electricity prices in Ontario. The selection of input data and LSSVM’s parameters held by BFOA are proven to improve accuracy as well as efficiency of prediction. A comparative study of the proposed method with previous researches was conducted in term of forecast accuracy. The results indicate that (1) the LSSVM with BFOA outperforms other methods for same test data; (2) the optimization algorithm of BFOA gives better accuracy than other optimization techniques. In fact, the proposed approach is less complex compared to other methods presented in this paper.

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A P-I-N diode is consists of three regions i.e. P-region, intrinsic region an N-region. The P-region and N-region are heavily doped compared to intrinsic region. The depth of the intrinsic region determines the reverse voltage of the diode. Thus, the deeper the depth of the I-region, the higher the reverse voltage produced. This is due to P-I-N diode operates in avalanche breakdown mode. In this paper, we will evaluate the thermal diffusion duration effect to the junction depth of the intrinsic region of a diode. The work includes wafer fabrication of a P-I-N diode, which is subjected to different diffusion times and followed by the measurement of current-voltage characteristic at wafer level. Results show that the longer the thermal diffusion duration, result in shallow intrinsic junction depth. Thus, lowering the reverse voltage.

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Lithium niobate (LiNbO3) nanostructures are prepared on n-silicon substrate by spin coating technique. The mixture was prepared with stirrer times; 8 h, 24 h and 48 h. They are characterized and analyzed by Atomic Force Microscopy (AFM) and X-ray diffraction (XRD) . The measurements show that as stirrer time increases, the structures start to crystallize to become more regular distribution, which helps to use in optical waveguide and other optoelectronics.

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To date, the most effective way for HCI (Human Computer Interaction) is depended on intermediate device- remote control, teach pendant or computer mouse, data glove and many others. The use of human gesture as an input to a computer system has the advantages in terms of its flexibility and ease of access. We proposed a gesture based control system for effective HCI interfaces based of coordinate features. The focus is on using the proposed coordinate features to correctly classify a number of human gestures corresponding to specific functions. The system was setup based on Kinect 360 and Lab view interfaces to control four specific functions based on four human gestures using coordinate features. The feasibility and the performance of the system was examined in terms of its accuracy, operational distance and lighting condition. Our experimental results showed that the proposed coordinate features could be used for gesture based remote control.

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Cornstarch/nano Hydroxyapatite (nHA) composites scaffold had been fabricated by the technique of solvent casting and particulate leaching. Different amount of nHA powder and cornstarch were used to produce different compositions of scaffold. Various compositions of nHA are expected to produce different dielectric properties and this can be applied as a basis of reference for the dielectric properties of the scaffold. Thus, this may enable us to quantify probably the porosity and biocompatibility characteristics of the scaffold by indirect measurement using dielectric parameters for our future work. In this study, there were three different proportions of cornstarch/nHA scaffold which had been fabricated. The dielectric constant (e'), dielectric loss factor (e?), reflection coefficient (S11) and transmission coefficient (S21) over frequencies ranging from 12.4GHz to 18GHz were obtained by transmission line method. The experimental cost can be reduced within this frequency range because the size of the prepared sample can be miniaturized. Based on the results and analysis, dielectric constant decreases when frequency increases due to Maxwell Wagner dielectric mechanism. Hence, ionic relaxation polarization mechanism is responsible for the changes of both the dielectric constant and dielectric loss factor which declined with increasing frequency. This preliminary experimental results showed that the sample exhibit reflection, transmission and absorption coefficients which are less than 1. It can be summarized that cornstarch/nHA scaffold exhibit low absorbability of electromagnetic wave within the frequency range from 12.4GHz to 18GHz.

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This study proposes the usage of I2C, (Inter-Integrated Circuit) communication protocol for a modular general purpose controller board of mobile robots. For the past few years, a trend of purchasing an off the shelf controller board by designers that would later be altered to fit a robot specification and design are has been increasing. This modular controller board allows users to use this modular controller board for their designs with minimal modification or without. Rather than purchasing an all-in-one controller board that might be costly, modularity means that only the needed modular board will be purchased. A total of four modular controller boards has been developed, which are main controller module, motor controller module, sensor module, pneumatic controller module, and one extension power supply module. All this modular controller boards incorporates the latest I2C communication protocol between the modular boards, which is faster and reduces the connecting wire between the modular boards. The potential of using I2C communication protocol in the proposed board is verified through a comprehensive series of experiments and the results suggest that the I2C is suitable and robust enough to be used in the development of this modular boards.

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In this paper, we present an indoor optical wireless model to evaluate the impact of direct and reflected light on the bit error rate (BER) performance of an indoor optical wireless CDMA system. In this model, we divided each wall into small reflecting surfaces and took into account multiple surfaces. Based on this model, the optical received power with and without considering the reflected light were calculated. Moreover, the BER performance based on zero cross correlation code (ZCC) analyzed. By using ZCC code, the BER gives better performance due to low effective power used at the photo detector .The results show good performance at the centre of the room compared to the edges. Therefore, the BER performance significantly depends on the position of the transmitter, the size of the room and the number of users. So, these parameters have to be considered whenever an indoor optical wireless CDMA is used.

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Nanocomposite has a good electrical performance. Material that had been utilized in this research is only the Silicon dioxide, SiO_2. Natural rubber (NR) consumption is due to the nature of interphase impact and viscoelastic matrix form multiple interphase with Linear Low-Density Polyethylene (LLDPE) was mixed with different amounts of SiO2 with Alternating Current and Impulse Test. LLDPE composition and the natural rubber ratio of 80:20 was used as the base polymer. These basic polymers are combined with SiO_2 of 1%, 3%, 5% and 7%. The parameters used are the thickness of the sample. Three thicknesses of sample used were 1.5 mm, 3 mm and 4.5 mm. This research was conducted to study the characteristics of polymer nanocomposite, SiO2. Based on this experiment, the increase in weight percentage nanofiller LLDPE and natural rubber also gives rise to the level of conductivity of the insulation. In addition, the weight percentage nanofiller used also affects the rate of change in conductivity of the insulation, the lower level. Besides, the thicker the sample, the higher the level of conductivity of the insularity.

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A study on the dielectric characteristics of various polymer nanocomposite materials should be conducted to design an electrically reliable high-voltage superconducting apparatus. Especially, the dielectric characteristics of solid insulation materials are important for designing current lead parts, and solid insulation materials are indispensable for designing superconducting coil parts. In this paper, dielectric experiments on Linear Low Density Polyethylene with Natural Rubber (LLDPE-NR) with different weight percentages of Montmorillonite (MMT) nanofiller are conducted under High Voltage Alternating Current (HVAC) and Impulse voltage for various types of electrode arrangement. Different types of electrode arrangement systems are used to examine the dielectric characteristics of insulation materials according to electric field concentration. During the first stage, several samples of LLDPE-NR are made by using hot compressed moulding processes which are consists of different percentages of MMT nanofiller such 3%, 5%, and 7% with thickness of 3mm. All these sample preparations are done according to steps with specific time of heating and cooling processes in order to produce the samples with the best condition and need to retain their morphological structures and also chemical compositions. Then, those samples are tested using both HVAC and Lightning Impulse Test until breakdown process occur. Based on collected and analyzed data results from both tests, 7wt % of nanofillers is the most suitable percentage of nanofillers that will enhance the electrical insulation characteristic.

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Based on a theoretical perspective, the primary function of insulation oils is to dissipate heat, and it serves as an insulator in between turn-to-turn windings in power transformers. To date, the majority of power transformer failures is attributed to the physicochemical reaction that takes place in the insulation oils due to the presence of heat, moisture content, oxidation and electrical stresses. Knowing that moisture content is one of the factors that leads to the degradation of transformer insulation oils, the main objective of this study is to examine the effects of moisture content on the breakdown voltage and Fourier transform infrared spectral characteristics of transformer insulation oils. Two types of insulation oils are chosen for this study: (1) conventional mineral-based insulation oil and (2) palm oil-based insulation oil which is a relatively new substitute for mineral-based insulation oils in Malaysia. The effects of moisture content is investigated by varying the amount of distilled water added into the oil samples from 1 to 5 ml, with an increment of 1 ml. Breakdown voltage test is conducted six times and the mean breakdown voltage is determined for each oil sample. The spectral characteristics of the oil samples are determined by means of Fourier transform infrared spectrometry. The breakdown voltage test and Fourier transform infrared spectrometry is carried out in accordance with the MS IEC 60156:2012 and ASTM D2144 standards, ensuring the reliability of the test procedures. Based on the findings of the study, it can be concluded that moisture content has a significant effect on the breakdown voltage and spectral characteristics of mineral and palm oil-based insulation oils – however, the effect is more pronounced for the mineral oil samples. Analysis of the Fourier transform infrared spectra reveals that the chemical composition of PFAE oil samples is not significantly influenced by moisture content and thus, this oil is a promising alternative for use as insulation oil in power transformers.

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Solar Photovoltaic (PV) system is environmentally-friendly which could reduce the consumption of electricity from the non-renewable energy sources. However, the generation of the PV system is highly dependant on weather conditions. More specifically, the shading of PV modules is a common phenomenon which can affect the performance of the PV system. Hence, this paper aims to establish relationship between the distance of a PV plant from a building object and its associated height. To achieve this, the Solar Pro software is used to simulate the shading conditions and estimate the PV system's output. For validity, the data of PV energy, total irradiation, Peak Sun Hour and performance ratio obtained from the simulation were compared with the Meteonorm software. The findings from this research suggest the relative distance of a PV plant should be located in relationship to its nearest building object. It is expected that such findings will provide a good rule-of-thumb for the solar PV system designer in selecting the viable project site.

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This paper is a comparative study of energy harvesting technology based on mechanical vibration. Recently, the study of the conversion of vibrational energy into electrical power has become a major field of research. Recent advances on ultra-low power portable electronic devices for low cost power supply are using conventional battery. However problems can occur when batteries die off because of their finite lifespan. In portable electronics, battery needs to be replaced when it dies replacement of the battery can become a tedious task because we do not know when the battery dies. People searched for more efficient portable power sources for advanced electronic devices. The critical long-term solution should therefore be independently of the limited energy available during the functioning or operation of such devices. Mechanical Energy Harvesting Systems may enable wireless and portable electronic devices to operate because they carry their own power supply that completely self-powered. Various types of vibration devices, piezoelectric materials and mathematical modeling of vibrational energy harvestings are summarized. This paper will investigates some of the research that has been performed in the area of vibration energy harvesting.

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The relatively short lifetime of batteries cannot fulfill the requirements for some wireless sensors. This is particularly the case where replacing batteries is difficult, dangerous and expensive. Energy harvesting systems have been proposed as a solution to such problem, In this paper, we proposed a model and presented the simulation of a MEMS-based arrayed energy harvester under ambient vibration excitation using Coventorware approach. This arrayed cantilever-based MEMS piezoelectric energy harvester operated under ambient excitation frequency band of 67 to 70 Hz, within a base acceleration between 0.2 to 1.3g produced an output power and voltage of 6.8 µw and 0.4 volt respectively.

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The upper and lower limbs motion is a natural phenomenon that realized in humanoid robot walking. The swaying arm angle range, R,_sa is introduced in this study to utilize the humanoid robot arm during walking. The main idea of this technique is the employment of right shoulder, left shoulder, right hip and left hip joint angle to investigate the torque at the torso in the vertical direction. The torso torque, t_t is computed using a method which utilizes the servo torque of right shoulder, left shoulder, right hip and left hip. The approach is tested using H25V33 NAO humanoid robot in the WebotTM Robotic Simulator. The result indicates that the method is successful in proving the torso torque, t_t produced during humanoid robot walking.

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This paper present a 5.8GHz flexible dipole antenna incorporated with flexibe frequency selective surface (FSS). First, the FSS structure, which utilizes the basic hollow cylinder to create the ring is investigated. Fast Film with ?r=2.7 and ts=0.13mm is used as a flexible substrate material for both dipole and FSS structures. Then, the dipole antenna is placed closely and parallel above the FSS structure with distance. The dipole antenna achieved for about 2.091dB gain enhancement and optimum return loss (S11) when the antenna is placed 0.5mm above the FSS structure. However the frequency response of the antenna is shifted and evaluated the return loss below than -10dB as the distance between the antenna and the FSS structure is increased. This design structure showed excellent performance when used for wireless communications.

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Mineral oil has been used as a dielectric medium in a transformer. Nowadays, due to the environmental issue, the properties and characteristics of vegetable oils are investigated in order to check its suitability to be used in power transformers. However, vegetable oils have its limitations on costing, period of use and oxidation stability. Vegetable oils used are palm oil and coconut oil which are highly possible to oxidize rapidly. To reduce oxidation from happen, antioxidants tert-butyl-hydroquinone (TBHQ) and a-tocopherol are used. Samples were electrically and physically tested and comparisons were made with the mineral oil. Electrical test such as the breakdown voltage was conducted. Besides that, chemical properties such as dynamic viscosity and moisture content were also being investigated. Results from the laboratory studies have shown that each tested sample has their own advantages and disadvantages. TBHQ and a-tocopherol were found to reduce viscosity and moisture content, as well as increase the breakdown strength and aging resistance of oil.

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We have investigated the carrier less amplitude phase (CAP) modulation format at different data streams for access network and simulated by using VPI software. The CAP signals with 1.25 Gbps and 2.5 Gbps are successfully transmitted over 20 km of single-mode fiber (SMF) with 1550 nm SM-VCSELs. The 3.79 b/s/Hz and 7.58 b/s/Hz of spectral efficiency are reported for 2D-CAP of 1.25 Gb/s and 2.5 Gb/s. The receiver sensitivity at FEC limit for B2B of both 1.25 Gbps and 2.5 Gbps is -18.3 dBm and -16.2 dBm, with the difference of 2.1 dB have been observed. After 20 km of transmission, a 2.5 dB difference was detected at the forward error correction (FEC) limit with receiver sensitivity of -18.3 dBm and -15.8 dBm respectively. The result shows that the CAP modulation format has feasibility and potential to deliver high data rate by employing simple baseband electronic design.

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The increased use of power electronic controlled equipment, such as variable speed drives, automated production lines, personal computers and non-linear electronic devices in power systems has given rise of voltage and current waveform distortion called as ‘harmonics’. Harmonic disturbances is one of the major issue in the power system. The harmonic source effectively disturb the industrial and customer power utility by changing the property of power stability. In order to determine the causes and sources of harmonic disturbances, it must started with the ability to detect the location of these disturbances. The harmonic source detection by using modelling the equivalent electric network is difficult to get an accurate equivalent circuit model because of loads changing dynamically. Thus, an automated way is required to identify the harmonic source disturbances. The analysis of harmonic sources disturbances using periodogram is presented in this paper. The periodogram is used to analyze the signal and represented the parameter of signals in power spectrum. Hence, the parameter signal are used to calculate the location of harmonic sources disturbances. The signal parameters such as RMS voltage, RMS current and difference angle of current and voltage are estimated from the power spectrum to identify the characteristic of harmonic disturbances. As a result, the characteristic of harmonic disturbances such as harmonic at downstream, upstream and both sides are identified based on harmonic impedances are presented in power spectrum. The difference characteristic of these harmonic source such as the difference magnitude of harmonic impedances are presented in result section. The end of this section, the new technique to identify the harmonic sources disturbances are presented and this technique is suggested to create a system for identify the harmonic sources disturbances.

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This paper presents the equipments necessary and methodology to convert a common-rail diesel engine to operate in dual fuel mode using compressed natural gas (CNG) as main fuel. A small quantity of diesel pilot fuel act as an ignition source to initiate the combustion. The conversion system was developed to reduce diesel consumption by manipulating and emulating signal from the common rail pressure sensor without major modification to the engine. The vehicle need to be inspected by several organizations after the conversion process to ensure that the vehicle is safely used on the road by the consumer. This paper is also presents the financial advantages of the conversion a diesel engine to CNG-Diesel dual fuel engine through the Return of Investment (ROI) calculation.

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Recently, the reduction or avoidance of permanent magnet (PM) usage in an electric motor has become significant research area due to high price of rare-earth materials. Under definite specifications and limitations of conventional interior permanent magnet synchronous (IPMS) motor in existing hybrid electric vehicle (HEV), the early performances of the recommended field excitation flux switching (FEFS) motor with no PM are evaluated based on 2-D Finite Element Analysis (FEA). Since the initial performances fail to acquire the target torque and power, design optimization based on deterministic approach of FEFS motor parameters is presented in this paper to attain the target performances. After a few cycles of design optimization, the enhanced FEFS motor has achieved the target power and torque of 41kW and 70Nm, respectively. In conclusion, the final design FEFS motor has the maximum power density of 1.75kW/kg which is approximately 49% more than power density in existing IPMS motor.

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In this paper, we propose a new code design with one cross correlation for the Optical Code Division Multiple Access (OCDMA) system. The performance of the system with the proposed Modified FCC code is analyzed by taking into account the effect of shot noise, PIIN and thermal noise sources. From the numerical results, it is found that the Modified Flexible Cross Correlation code (MFCC) provides the best performance, in terms of the signal to noise ratio (SNR) and the bit error rate (BER), compared to MDW (Modified Double-Weight) and RD (Random diagonal) codes. Moreover, the simplicity in code construction and the flexibility in cross correlation control have made this code a compelling candidate for future Spectral Amplitude Coding Optical Code Division Multiple Access (SAC-OCDMA) applications.

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Photovoltaic (PV) system is considered to be a renewable energy which is derived from solar energy. Solar energy is an abundant resource which is clean and green energy taken from nature. However, the amount of electric power generated by solar arrays varies with the weather. This will bring inconsistency in generation of output power. This paper proposes a maximum power point tracking (MPPT) of photovoltaic system based on Adaptive Neural Fuzzy Inference system (ANFIS) controlled using field programmable gate array (FPGA). The performance of proposed method is evaluated using MATLAB/SIMULINK. The proposed method is capable to maintain the consistency of power generated by solar panel under varies conditions.

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This paper presents a design of 2.4 GHz low noise amplifier (LNA) for wireless sensor network (WSN) applications using CMOS 0.13 µm Silterra process. The proposed LNA employs a self-biased inverter to obtain high gain and able to operate at low supply voltage. The simulation results indicated that the proposed LNA achieves an input return loss (S11) of -37.7 dB, output return loss (S22) of -28.1 dB and gain of 10.5 dB. Moreover, the noise figure (NF) of 5.4 dB and the input third order intercept point (IIP3) of -10 dBm is obtained at 0.9 V supply voltage. The chip area is 0.49 mm2.

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In the designing of an acoustic room or other acoustically demanding spaces such as concert hall, community hall and classroom, it is essential to have the sound is distributed equally to all part of the room. Conventionally, the calculation of acoustic room model is done manually by inserting vertices and surfaces one by one from the sound source respect to the model room which is the process is time consuming. This project proposes the way of modelling the room acoustics prediction by using MATLAB to meet the specification of acoustically demanding space. First, the 3D model of the room or halls is being created in Sketch Up and the file will analyse using Odeon. In the same time, calculation will be done by using MATLAB. Subsequently, by using Odeon software, the calculation can be proven, thus the sound propagation can be simulated from any part of the room or halls easily than before to modelling the acoustically demanding space. Thus, the room acoustics prediction can be done accurately and the optimum room for audio demanding space can be created.

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This paper aims to present the mathematical analysis for the single-walled carbon nanotube (SWCNT) composite material, in order to derive its effective conductivity model and its plasma frequency formula. This composite material consist of SWCNT coated by other materials. The effect of average thickness of coating layer on the model of an effective conductivity of SWCNT composite material, will be investigated and discussed. Meanwhile, present the effect of using different coating materials with different radii of SWCNTs on the plasma frequency and effective conductivity model of this composite material. The results of this work represent a theoretical study for the properties of SWCNT composite material, which is useful for the antenna application. The parameters of this composite material extracted in this work can be utilized to designing and implementing the dipole antenna, in order to estimate the electromagnetic properties of SWCNT composite material.

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System identification is a field of study involving the derivation of a mathematical model to explain the dynamical behaviour of a system. One of the steps in system identification is model structure selection which involves the selection of variables and terms of a model. Several important criteria for a desirable model structure include its accuracy in future prediction and model parsimony. A parsimonious model structure is desirable in enabling easy control design. Two methods of model structure selection are closely looked into and these are deterministic mutation algorithm (DMA) and forward selection procedure (FSP). The DMA is known to be originated from evolutionary computation whereas FSP may be listed under the study of regression. They have close similarities in characteristics, more specifically known as forward search in model structure selection. However, both also function in a population-based optimization and statistical approaches, respectively. Due to the closeness, this research attempts to clarify the advantages and disadvantages of both methods through model structure selection of difference equation model in system identification. Simulated and real data were used. To allow for fair comparison, DMA was altered so as to equalize its strength, where applicable, to that of FSP. In the real data simulation, both methods obtained the same model structure whereas in simulated data modelling, only DMA was able to select the correct model structure. This concludes that DMA not only has the advantage of simpler procedure but it also superseded the performance of FSP, even with a handicapped alteration.

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Studying the characteristics of annular fin is a key research problem in many thermal applications. A comparison of performance of the exponential and parabolic annular fins of varying geometry parameter is reported in the present work. The governing differential equation for the fins has been derived to study the temperature distribution of the fins with insulated tip. A parametric study is then carried out by varying the geometry parameters in the governing equation to investigate the effect of on fin performance and the results are presented in graphical form.

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The effect and interactions of various parameters on the Neck Moment experienced by a three year old child during side impact is investigated using a pre-validated numerical model. The simulation involves a HYBRID III 3-year old child Anthropometric Test Device (ATD) model restrained in a Child Restraint System. The numerical model assembly is comprised of a combination of both Finite Elements (FE) and Multi-body ellipsoids (Mb). It is subjected to lateral and oblique side impact crash using the Prescribed Structural Motion method. The model is adapted to investigate the effect of intrusion and oblique impacting angles. The Latin Hypercube Sampling (LHS) design is adopted for the Plan of Experiments in which six parameters are subjected to two different impact velocities. Statistical methods are employed in which both quantitative and qualitative parametric studies are carried out. The study indicates greater parametric significance at high impact speed and at wide impact angles (? = 60°). The impact angle parameter is largely shown to be the most significant parameter in affecting the Neck Moment response. The impact angle parameter trend is found to be very similar for both impact speeds. A relatively safe region is found to exist between impact angles 45° and 65°.

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Being a novel material by having high strength to weight ratio, magnesium (Mg) alloys have attracted researchers working on variety of applications such as, automobile parts, aerospace and most recently in biomedical implants. Surface Integrity (SI) of any manufactured products has a significant effect on its functional performances, as well as corrosion resistance. It has been noticed that, the temperature is the most vital factor that influences all SI factors. The present study is to understand the temperature distribution occur in the Mg alloy which is machined under different operating condition i.e., dry and cryogenic machining. A finite element model (FEM) is used for the analysis. The investigation shows that, the distributions of temperature in the work piece, chip and tool is in the form of isothermal lines. It also shows that highest temperature reached on the machined surface is significantly reduced under the cryogenic condition. Results have found to be in good agreement with the experimental results.

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3-Dimensional elbow implant was built with SOLIDWORKS 2014 and the finite element analysis was performed with ANSYS. Designs of elbow implants were compared based on the linked, semi-constrained elbow implant design that was chosen and built in this study. The daily activities was said to be achieved within range of 30 degrees to 130 degrees of angle of flexion. Three common angles were picked to perform analysis, which are 30 degrees, 90 degrees and 130 degrees. Three types of materials were chosen for the metal components of the elbow implant which is Titanium, Copper and Stainless Steel. Polyethylene was chosen as the material for bushing. Values 0.1kg, 0.5kg, 1.5kg and 2.5kg were given to objects involved in daily activities. Results of stress from "Equivalent (von-Mises) Stress" and "Maximum Principal Stress" were compared. After the analysis, it was discovered that Titanium is the best material for elbow implant production, and failure of implant will likely to occur at the lower part of the humerus component and mid-ulnar component. The maximum values of the stress for all three materials of elbow implant were lower than the Ultimate Tensile Strength of the material. Therefore, the implant will provide a proper stress distribution when the individual perform his or her daily activities.

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Experimental investigations were made to measure the variation of pressure development in a confined space at different equivalence ratio of methane-air combustion. A cylindrical vessel combustor that correspond to spherically expanding flame is used in this experiment. The experiment is subjected for only premixed methane-air mixture from five different equivalence ratio, ? which are lean (0.7, 0.8), stoichiometric (1.0) and rich (1.2, 1.4). The instantaneous and maximum pressure were recorded using dynamic pressure transducer. The result of pressure profile at stoichiometry condition was compared with the previous work by other researcher. Based on the experimental investigation, the trend line of the buildup pressure profile at various equivalence ratio in this experiment is similar as obtain in previous work done in which shows increment as the equivalence ratio moves from lean to slightly rich mixture. However it will eventually decrease when the mixture is too rich. The knowledge of maximum pressure can further be used to interpret the burning velocity of flame propagation.

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For heat assisted bending process, an irradiation of the whole bend line together with optimum temperature gradient between two adjacent surfaces is most favorable. However, it’s depends on type of the used heat source with high intensity heat energy into the work piece is very importance. In this paper, an experimental and numerical technique have been used to study an efficiency of the infra-red heater to radiate a mild steel plate. Initially, an experiment has been conducted to determine temperature distribution at the selected points on the work piece. The result indicates that the infra-red heat is not suitably used as a heat source for the heat assisted bending process. Then, a finite element model (FEM) has been developed to replicate the conducted test. Thermal distribution results from FEM shows good agreement with the experiment results. The result proves the validity of all the input parameters in the developed FEM model.

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Recently Aluminium alloy, exclusively AA 6061 is used in the automotive, aircraft, marine and construction industries due to it is excellent properties such as noncorrosive, strength to weight ratio and rewards over than steel in ductility. Four groups of particle size were chosen (25, 63, 100, mix) µm. Each group has compacted by three specimens for various of compacted pressure (5, 7, 9) tons, the holding time and sintering temperature were constant (20) min, (552) oC respectively. The result of mechanical properties shows that the compression strength increase with increasing compaction pressure for all groups and the various of particle size (mix) will be given the best compression strength (134Mpa) due to it will be given a smaller amount of pores. Whereas the others have less value due to the large amount of pores. Micro-hardness has been getting the large value of the mix group (61HV), while the others have less value. Therefore, it can be concluded that, cold press forging for powder metallurgy could be one of the alternative production process instead of the conventional method that has been carried out melting phase, which contributes to a sustainable manufacturing process technology in the future.

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In most developed countries, the statistical data of road traffic accidents involving motor vehicle-pedestrian crashes have registered much cause for concern and consequently, a concerted effort by various sectors have for the past two decades been brought to bear towards mitigation efforts. Amongst the different approaches in this direction, it has been established that pedestrian kinematics during impact plays an important role in the ensuing injuries particularly to the head, and has been shown to have a direct bearing with the vehicle front-end shape. This has eventually led to some optimization efforts of the vehicle front-end geometry but due to the complex nature of the problem, many difficulties have been encountered and an exhaustive comprehensive solution has yet to be achieved. In a step towards an attempt in addressing some of these issues, this paper demonstrates the feasibility of an alternative method for developing an optimization friendly deformable vehicle structure, having simple, easily modifiable profile geometry requiring short processing time for the particular purpose of performing multi-parametric optimization of the vehicle front end shape with the goal of minimizing the sustained head injuries of the pedestrian. The proposed hybrid case model has successfully achieved an efficiency of 99.85% in CPU time in comparison to a full finite element model. The polynomial response surface method is employed to generate the mathematical models which in turn are used for the optimization process. The mathematical models developed are found to show acceptable predictive capabilities with the child model having the highest model fitness of 90.7%. The optimization is successfully able to find a front-end geometry which minimizes the HIC values for both the adult 50th percentile male pedestrian and the 6 year old child pedestrian. Finally, the study further reinforces the necessity for the consideration of the relationship that exists between pedestrian kinematics and vehicle front-end profile in design considerations as well as in development of further test procedures and safety mitigation methods.

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The content of Buton asphalt from Buton Island varies but not optimally used. The structure of asphalt which contains a lot of aromatic compounds requires hydrocracking in order to be cracked into smaller hydrocarbon fractions that can become an alternative fuel source. This research was conducted in 2 stages: preparation of the catalyst Ni (3)-Pd (1)/Zeolite-Y 1%, followed by hydrocracking of Buton asphalt. Hydrocracking was done asphalten feed is heated in autoclave in the temperature of 400 0C and the asphalt vapor goes into the fixed bed reactor containing catalyst with together with hydrogen gas flow in constant rate. The reaction in is considered to be steady with the choice reaction time 1 hour and starts in the 10 minute after asphalten feed temperature autoclave achieve 400 0C. The variable observed is the reaction temperature and pressure of in the range of 350–550 0C and 4–8 atm. The liquid hydrocracking product was analyzed by Gas Chromatography Spectrometry (GC-MS) and GC to determine the hydrocarbon compounds and the percentage of hydrocarbon fractions. The results are hydrocracking of Buton asphalt produces fuel gasoline fractions (C7-C12) and diesel fractions (C13 –C15). Hydrocracking provides optimal yield of 6.75% at temperature of 500 0C and balanced selectivity gasoline fractions and diesel fractions obtained were 56.59% and 43.40%. When the hydrocracking product is expected to be in liquid form, the gasoline fraction selectivity temperature and pressure should be 400 0C and 6 atm, respectively. In this condition, the gasoline fraction obtained was 62.25%.

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One of the challenges in the production of virgin coconut oil (VCO) by natural fermentation is to keep the process temperature at the optimum condition for the growth of the bacteria. Grated coconut waste (GCW) is the waste from VCO productions that could undergo a solid state fermentation in which the reaction is exothermic so that the heat is generated during the fermentation. In this research, the use of GCW as a heating jacket and temperature stabilizer during the VCO production and particularly the effects of the mass ratio of GCW to coconut cream and the length of GCW fermentation times to the process temperatures, VCO yields and VCO quality were studied. It was found that the solid state GCW fermentation was an exothermic reaction and could reach a temperature of 40 0C in the 7 (seven) days of fermentation. GCW with fermentation times of 24, 48 and 72 hrs, respectively, could be used as a heating jacket and temperature stabiliser. The optimum mass ratio of GCW to coconut cream which led to the maximum VCO yield of 22% was 2:1. The VCO contained lauric acid of 50% and moisture of < 0.5%, it was colorless and had a specific coconut oil aroma which met an Indonesian National Standard (INS) and Asian and Pacific Coconut Community (APCC) standard. The use of GCW as a heating jacket was not only avoiding the failure of the VCO production by natural fermentation due to a low process temperature but also enhancing the VCO yield as well as keeping the VCO quality.

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The use of the chemical flocculants can cause health and environmental problems. The alternative bio-flocculants is chitosan. In this study, the chitosan was prepared as flocculants for harvesting the microalgae chlorella sp. The aim of this research is to investigate the flocculation behavior and mechanism of a chitosan. Chitosan, nanopartikel chitosan and chitosan magnetite were prepared as a flocculant. Nanoparticle chitosan was prepared by crosslinking reaction with Sodium Tri Poly Phospat (STPP). The chitosan magnetite was prepared using iron (III) chloride and iron (II) chloride. Various concentrations (25, 50, 75 and 100 mg/L) of chitosan were tested. The Fourier Transform Infrared spectrometry (FTIR) showed that the FTIR spectra of nanoparticle chitosan the peak of 1655 cm-1 disappear and 2 new peaks at 1645 cm-1 and 1554 cm-1 appears. The transmission electron microscopy (TEM) identified the average diameter of particles was about 23.08 -61.54 nm. The magnetic property of the obtained magnetic composite nanoparticles was confirmed by X-ray diffraction (XRD) and FTIR. The saturated magnetisation reached 21.5 emu/g. The flocculation efficiencies of three flocculants were investigated. The effect of chitosan dose on harvesting efficiency of Chlorella sp was also investigated. Results showed that Chitosan nanomagntite was the best flocculants in their category in terms of flocculation efficiency at 98 % floc rate. The higher floc rate was conducted at 100 mg/l of chitosan nanomagnetite.

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Thickness and morphology of electrodeposited coating is crucial in every application of protective finish to ensure high quality and performance is achieved. How a deposited metal is distributed across the cathode surface is greatly affected by current density distribution. To calculate current density distribution prior to the design of electrochemical system is essential in order to optimize the uniformity. The effect of cell geometry and kinetics on current density distribution in nickel electrodeposition from low electrolyte concentration and narrow interelectrode gap has been investigated. This electrochemical system was required for nickel pattern transfer using Enface technology. The modelling and simulation was carried out by solving Laplace’s equation in the potential model theory considering appropriate boundary conditions using the Boundary Element Method. The simulation was accomplished by using software of Elsy (ELSYCA NV). The results show that the current density distribution using 2D and axy-symmetrical system was identical for all electrode sizes. However, current density at the electrode edge in the axy-symmetrical model was higher by around 19 % which might be due to the extra space around the electrode. Thus, 2D configuration was sufficient to represent the actual reactor geometry for the experimentation. In a parallel plane electrode configuration, the current density significantly increases at the edge of the cathode. The current density was uniform in the range of 0.08< x/L (normalized length) < 0.92 which was over 80% of the surface area. Therefore, the patterns should be located at the middle of the anode for ensuring a uniform thickness of deposited nickel pattern was achieved.

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The extraction of glucomannan from Porang flour was conducted simultaneously with starch hydrolysis using amylase. Only the extraction process is reported in this paper. The kinetic of the extraction was analyzed using second order kinetic model. The influence of two operating parameters, i.e. stirring speed and solid mass/volume ratio, were studied. The value of kinetic parameters, i.e. the initial extraction rate, h, extraction capacity, Ce, and the extraction rate constant, k, increased as stirring speed increased, i.e. 4.95 times, 2.5 times, and 1.4 times, respectively, as the stirring speed increased from 300 rpm to 600 rpm. The increase of solid mass/volume ratio from 2.67 to 10.7 g/L results in an increase in h (8.86 times) and Ce (3.26 times) but not in k, which decreased (by 0.833 times).

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Biodiesel is one of the key products to avoid the world energy crisis in the future. As by product of biodiesel production, glycerol should be utilized effectively to enhance the competitiveness of overall biodiesel production. In this study, the development of solid catalyst based on the abundant natural resources, zeolite was investigated. The performance testing of catalyst product in the glycerol acetylation were also evaluated at different temperature and compared with other commercial catalyst. Natural zeolite was activated with strong acid (H2SO4) and impregnated with ZrOCl2.8H2O at 80 0C. Based on XRD analysis, the crystalline structure of zeolite was not damaged during the process and the impurities were decreased. The BET surface area of zeolite catalyst increased during activation process from 54.318 m2/g to 172.45 m2/g. The Zr-Zeolite catalyst has been tested on the glycerol acetylation with acetic acids for triacetin production. The calculation of triacetin selectivity and glycerol conversion was done based on Gas Chromatography analysis. The results of triacetin selectivity and glycerol conversion are 26% and 94.3%, respectively for reaction temperature 110 0C and 30 minute. By comparison to other commercial catalyst such as Amberlyst-15 and K-10, the catalyst offered higher selectivity and product.

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Virgin coconut oil emulsion (VCOE) is an alternative VCO product which has a reduced amount of oily taste when the VCO is consumed directly. This study was aimed to obtain the formulation of VCOE and determine the physical and chemical properties and also stability of emulsion with the addition of mixed emulsifiers Tween 80 and Span 80 (T80S80). Emulsions were formulated using mixed emulsifiers with the mass ratio of T80 to S80 of 100:0; 80:20; 60:40; 40:60; 20:80 and 0:100, respectively. The best ratio of the emulsifier was used to determine the stability of VCO and water mixtures with the diversity ratio of VCO to water were 90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, 20:80 and 10:90, respectively; the concentrations of emulsifier used were 1, 0.75 and 0.5%. VCOE was successfully formulated in the mixture of VCO-water ratio of 80:20. The VCOE products have high viscosities in each concentration of emulsifier and remained stable in room temperature. The contents of the peroxide number were 1.51 to 1.53 meq/kg sample and free fatty acid were 0.09 to 0.1%, which indicated that the emulsions were not rancid.

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The 1,3-dinitroglycerin is an important compound to synthesize glycidyl nitrate, monomer of polyglicidyl nitrate (PGN). PGN is the most energetic polymer which can be used as binder of propellant. This compound was produced from the nitration of glycerol with nitric acid. This paper aims to obtain optimum conditions nitration of glycerol with nitric acid. The reaction was run in a flask equipped with a nitrogen purge for stirring. Nitration of glycerol to 1,3-dinitroglycerin was studied in the temperature range of 10-30 0C, the molar ratio of nitric acid to glycerol 1/1 to 7/1 and nitric acid concentration of 69%. %. From experiments it is known that the optimum conditions of nitration of glycerol with nitric acid is a reaction temperature of 20 0C, the mole ratio of nitric acid / glycerol 5/1 and the concentration of nitric acid 69%.

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Pink guava (Psidium guajava L.) is a tropical fruit rich in high-profile nutrients such as polyphenols, which act as antioxidants. After processing pink guavas for fruit juice, the residual pulp still contains a large amount of polyphenols. Our previous study indicated that the total polyphenol content of residual pulp pink guava after processing ranged 0.03 to 0.12 mg/g. The aim of present study is to find the best solvent for the extraction of polyphenols. The highest total polyphenol content was obtained using methanol as a solvent and the second highest was obtained using water as a solvent. A mixture of methanol and water at a ratio of 60% increased the total polyphenol content. The best extraction time was 180 minutes and a ratio of 1 g of pulp waste to 25 ml of 60% methanol/water solvent yielded the highest polyphenol content. The Folin-Ciocalteau method was used to determine the total polyphenol content.

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Efforts have been made to improve low rank coal adsorption capacity, such as acid washing and reaction with oxygen to enhance its active sites. In this research, the coal was subjected to oxidation using hydrogen peroxide solution. After treatment, the coal was subjected to elemental and FTIR analyses. The treated and untreated coals were then applied for adsorption of divalent and trivalent metal cations such as Cr3+, Fe3+, Cd2+, and Co2+. The adsorption experiments were carried out in batch tests, applying constant temperature and constant stirring speed. The result showed that treated coal possessed better adsorption capacity than that of raw coal. It was also indicated that trivalent cations were adsorbed better than divalent ones signifying better interaction of trivalent ions with coal surface.

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Catalytic cracking of nyamplung oils was performed over ZSM-5 catalyst. This process is carried out in a packed bed reactor which is equipped with two-stage preheater to convert the nyamplung oil into vapor form. The reaction was studied in the temperature range of 350-450°C and reactor length of 2-5 cm. The kinetic study of catalytic cracking of nyamplung oil is represented using lumped parameter model based on 5-lumps model which is modified from 4 and 6 model. This model was developed by classified the reactant and product into five-lumps, namely C4-C11, C12-C15, C16-C18, gas and coke. The simulated data which obtained from the model gave satisfactory results with the experimental data.

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In many developing countries such as Indonesia, one of a great potential area which will continue to grow is textile industry. These industries usually utilized artificial color, also known as synthetic dyes, in their manufacture production. The synthetic dyes contained in wastewater generated from textile industrial processing were refractory to degrade and toxic to human. The Reactive Red 2, as one of the important synthetic dye was used as a model organic pollutant in this research. However, Advanced Oxidation Processes (AOPs) have shown great potential in treating pollutant such as the treatment of textile dyes. In this study, degradation of RR 2 was examined by using Fenton and photo-Fenton oxidation processes, as one of H2O2-based AOPs. The RR2 concentration of 150-300 ppm, [Fe2+]/[H2O2] molar ratio of 1:20-1:80, and reaction time of 0-20 minutes were investigated on the degradation of dye in term of color and Chemical Oxygen Demand (COD) removal. The degradation of color and COD were strongly in?uenced by the initial concentration of dye, the [Fe2+]/[H2O2] molar ratio, and the reaction time. The color degradation of 69% was reached within 20 minutes of reaction by using Fenton process for all molar ratio of 150 ppm of RR 2 concentration usage. While the color degradation of 99.9% was obtained only in 10 minutes of reaction by using photo-Fenton process at [Fe2+]/[H2O2] molar ratio of 1:80, and also a maximum COD degradation of 95% was achieved when using RR 2 concentration of 150 ppm within 10 minutes of reaction.

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A study of crude turpentine esterification was carried out using strong acidic cation exchange resin Amberlyst 15 as catalyst. During the esterification process, the isomerization of a-pinene also took place under the catalytic condition. To obtain the optimal reaction conditions in a stirred-tank reactor, the effect of different parameters such as mixing speed, ratio of reactants, temperature and the reusability of catalyst on the conversion of a-pinene and the selectivity of bornyl acetate were investigated. Kinetics of the reaction was also performed in the temperature range of 50 – 100 0C. To explain the reaction rate equation and to determine the reaction rate constants and reaction activation energy, reaction products were grouped as acetates and isomers and a pseudo homogeneous - first order reaction model was used. The proposed kinetic model shows a good agreement with the experimental data.

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This research was proposed to an enviromentally fuel from syngan of corncob. The feasibility and operation performance of corncob gasification in small downdraft gasifier was studied. The concorb gasification was carried out at 30-35% of the necessary air for stoichiometric combustion (the equivalent ratio, F= ±0.35). The gasification temperature of 600-800 0C and the fire power of gasifier, FP of 5 kWth were obtained in this experiment. The syngas could be burned with a reddish blue flame like liquid petroleum gas (LPG) in conventional domestic stove. The air flow rate of 0.1-0.2 kg/min. for syngas combustion (about 50% for complete combustion) generated flame temperature of around 850 0C. The thermal efficiency and the cold gas efficiency about 40% and 70%, respectively. Economic and energy evaluation of corncob and syngas utilization was also conducted. The potential energy of waste corncob could fulfill the energy needs of the entire small industries that are located in West Bandung District. An implementation study of syngas utilization in one of the small industries for cooking fish gave the gross profit margin about IDR 15,749. The difference profit between the use of LPG and the use of syngas was about IDR 1,716 /kg fish. The utilization of waste corncob on a small industry as a pilot scale is expected to substitute the use of ±29 million kg of LPG/year.

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Bitumen is a mixture of organic liquids which is black, high viscosity and it is sticky materials where it can be applied in several of application. Waste sludge can be used as another alternative to formulate the bitumen by manipulating ratio needed. Waste sludge consists of mineral oil solid waste, which includes oily sand, tank bottoms and other three kinds of sludge from refineries such as dissolved air flotation scum, excessively activated oily sludge and bottom sludge of oil from pools. Waste sludge is the major source of pollution produced in the process of oilfield production and development. In order to formulate the bitumen, other material that is needed include mineral oil, waste sludge and crumb rubber. The form of crumb rubber is form from discarded tire. Generally, the tire rubber is ground to a particulate or crumb prior to adding it to bitumen. This form of the tire rubber is called Crumb Rubber and the mineral oil is used as the medium to heat up the crumb rubber until it is melt and dissolved. The main objective in this experiment is to formulate and identify the best ratio of the bitumen produced. The method that is used to formulate is heating and mixing process which is being conducted inside the fume hood. So that it can absorb the fume released when the process is conducted. The key parameter during the process is weight of the sample, temperature, time and the speed of the mixer (rpm). Once it is produced, then the sample need to analyze based on the density 15 0C using ASTM D70 method, viscosity test by using ASTM D2170, penetration @ 25 0C test which by using ASTM 5 method and softening point test which is by using ASTM D36 method. The best ratio by far is (1:2:1.2) formulation by having viscosity of 93 centipoise, density of 1.0398 Kg/L, softening point which is at 62 0C and penetration which is at >40 mm of penetration. The sample that is formulated were then being compared with the actual bitumen sample.

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In general, industrial processes have a multi-variable characteristic, which is sensitive to the disturbances. Therefore, it is important to study the influences of disturbance through a simple but reliable tools. Quadruple tank is a simple tool in process control that represents a complex multivariable dynamic process. This article investigates the effects of an introduction of heaters to the system as well as the interaction among the tanks. The flow rates and energy inputs to the tanks, respectively, are considered as the manipulated variables, while the liquid temperatures and level are controlled; hence the system becomes a 4x4-MIMO. The closed loop simulation is designed for comparing controlled variable response between P only-PID and IMC controller. Error criteria is evaluated by IAE. In level change of minimum phase, IAE’s value of level and temperature controller IMC show better result than P-only. On the contrary, P-only controller indicated faster response (settling time) than IMC. IMC is used for solving time delay problem on conventional controller. Thus, based on settling time and wide range of tolerance, P-only shows a better work than IMC. However, using IMC is the best decision if the accuracy and precision from set point are the main of controlling system. In temperature change, based on settling time and IAE, IMC gives the best result than both P-only for level controlling and PID for temperature controlling. Divergent oscillation of controlled variable response, wether level or temperature, of non-minimum phase indicates unstable trend and hard to control by P-only for level and PID for temperature. In contrary, temperature change controlled variable result of IMC, either lavel control or temperature control, are indicated better result than P-only and PID. As a result, IMC controller can be considered to be a reference at non-minimum phase control system.

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This paper describes how to develop a decision support system for classifying production equipment by considering a Multi Criteria Decision Making (MCDM) Method for Productivity, Quality, Cost, Delivery, Safety (PQCDS) indicators based on its condition. The study was conducted by using fuzzy assessment approach. The purposes of this study are: to define each criterion of each indicator; to determine fuzzification of value of each criterion; to design appropriate fuzzy rule base; and to develop a decision support system. The Categories of equipment were divided into 3 classes, such as: critical, mayor, minor. In this study, fuzzy rules were designed based on expert’s knowledge and experiences. Finally, the results were simulated and compared with conventional method.

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This study explored a new method and process of design denture using CAD technology to develop a template of a complete denture. Computer aided design were used as a tool of the design process. Occlusion curve was set up as variable as to follow patient size. The maxilla and mandible teeth arrangement were treated as a template of Malaysian user. The accuracy of design is the main aspect of concern that match the patients' data so that the outcome product would be suitable with maximum comfort for the patient. The product of design template will be matched with the conventional method to compare the tolerance between both. The new design template helps to reduce the time consumption of conventional carving method. The final output of 3D geometry teeth templates design will represent the patient details.

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Knowledge and technology transfer is the way to improve technology capability. The process of knowledge and technology transfer can be analyzed based on knowledge classification. It involves tacit and codified knowledge. Each type of knowledge has a unique characteristic. The diversity of characteristics will potentially affect the result, and indeed the success, of knowledge and technology transfer. It is important, therefore, to understand any differences in phenomena associated with the process of transferring knowledge and technology base on knowledge classification for SMEs. Using data from hundreds of SMEs and in-depth discussion with the peak bodies of government agencies, universities and industries, the policy directions for government regarding to knowledge and technology transfer to support local industry in developing economies were developed.

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Ultra-high molecular weight polyethylene (UHMWPE) is a polymer with superior mechanical properties. However, processing of UHMWPE has been a great challenge due to the extremely high viscosity of UHMWPE which limits its utility in applying it for some processing technology such as Fused Deposition Modeling (FDM) which receives raw material only in filament form. Recent processing technology highlighted that extrusion technology is the most economical way for producing filament. Thus, the aim of this work is to improve the processability of UHMWPE for extrusion process via blending with polypropylene (PP), with enhancing the mechanical properties of UHMWPE. The result shows that UHMWPE/PP blend at 80/20 ratio provides maximum melt flow rate. The highest thermal stability observed at 90/10 ratio of UHMWPE/PP blend. Thermal decomposition curves revealed that UHMWPE/PP blends and both pure UHMWPE and PP decomposed above 250 °C.

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Blended biodiesel fuel is considered as an alternative to current fossil fuels in many applications, at low blending level less than 20% biodiesel. The fuel physical characteristics are among the most important parameter to determine the quality of each fuel. Though biodiesel can replace diesel satisfactorily, problems related to fuel properties persist. In this study diethyl ether (DEE) was used as additive to the palm biodiesel-diesel blended fuel B30 and B40 in the ratios of 2% and 6% by volume and tested for their properties improvement according to ASTM D7467 standard procedures. The tested fuel samples were compared with diesel fuel (D) and palm biodiesel (B100). The minimum pour point for the blended fuel was -7 oC for B30DE6 compared to 14 oC for palm biodiesel, the results shows that the best properties was for B30DE6 where the presence of diethyl ether additive helps to reduce the viscosity by 35%, density by 3.6% and acid value by 57% compared to palm biodiesel. On the other hand, a slight decrease in the energy content has been found with increasing additive and blending portion compared to pure diesel and the lower energy content value was for palm biodiesel. However, the properties of biodiesel and its blended fuel with additive still meet the requirement of ASTM D7467 standards.

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In this paper, the behaviour of three different nanofluids (Cu, Al2O3 and TiO2-water) on a stagnation-point flow and heat transfer over a porous vertical shrinking/stretching surfaces for suction/injection are analyzed. It is important to note that the order of magnitude of the variation in the temperature profiles depends on the nanoparticles as they have different physical and mechanical properties such as dynamic viscosity, density, specific heat capacity and thermal conductivity. The Navier-Stokes equations for incompressible viscous flow are transformed by similarity transformation into a system of high order ODE that are executed numerically using MAPLE 18 software. The effects of various controlling parameters on (Cu, Al2O3 and TiO2-water) nanofluids are studied. The present results for special cases are found to be in good agreement with previously published works. Copper nanofluid is found to be the most reliable amongst the three nanofluids and best suited for stagnation-point flow towards a porous surfaces.

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Dip coating process promises good deposition of nickel-alumina catalyst on metal surface for various applications especially in gas conversion reaction. This study investigates the effect of different metal substrate roughness surface on nickel-alumina catalysts thin film formation. Three different stainless steel substrate roughness' used, 0.18 µm, 0.13µm, and 0.09µm. The solgel was prepare from Nickel (II) nitrate hexahydrate and Aluminum isopropoxide. After dip coating, the samples were being heat treated at 300?C for 90 minutes. These deposited thin film were characterized by using Atomic Force Microscopy (AFM). AFM result showed the presence of micro-sized, grain-like particles in the nickel-alumina topographical and morphological coating. Moreover, the AFM had clarify two main findings which are, thin film thickness and roughness is proportional to the substrate’s roughness and also proportional to withdrawal speed. However, the withdrawal speed showed limitation of film formation due to drag gravitational force and coating speed factor. Characterization of the deposited thin film samples had shown thickness of 0.5 – 6.0?m and roughness of 0.1 - 1.0?m.

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In this paper a formulation of boundary element method for shear deformable plate theory with material nonlinearity is presented. The material is assumed to undergo small strains. The von Mises criterion is used to evaluate the plastic zone and elastic perfectly plastic material behaviour is assumed. An initial stress formulation is used to formulate the boundary integral equations. Not only the plastic strain due to bending but also the plastic strains due to membrane are considered. The domain integral due to material nonlinearity is evaluated using a cell discretization technique. A total incremental method is applied instead of an incremental and iterative procedure, to solve the nonlinear boundary integral equations. Numerical examples are presented to demonstrate the validity and the accuracy of the formulation.

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The well-known approximate solution of harmonic balance is compared with one of the techniques of perturbation, the multiple scale method. Both chosen analytical method are compared in terms of degree of nonlinearity of a hardening base excitation system. The assumed solution in harmonic balance is taken to single mode while multiple scale solution is assumed to have the solution of a first order expansion. Both methods are solved to attain the frequency response equation and the response of both curves are plotted and compared to show the differences in each method with the same value of nonlinearity. In the chosen parameter of nonlinearity, a=0.03 and a=3.5, harmonic balance method appears to tilt at a higher degree than that of multiple scale method thus showing higher accuracy in terms of nonlinearity from the comparison.

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Harvesting energy from ambient vibration source is a promising method for providing a continuous source of power especially for low power microelectromechanical system (MEMS). Thus, multiple methods were proposed in order to overcome the linear resonant generator system. This paper presents experimental results on two modes (softening and bi-stable) the use of magnets for improving the functionality of energy harvesting device under constant input displacement. Two set of the experiments were conducted. The quasi-static measurement was conducted to investigate the system stiffness and the dynamic measurement was conducted to investigate the performance of the response across a frequency range. The results for four configurations which operate in attractive and repulsive mode with a fixed gap between the magnets are investigated. The result shows that there is a wider bandwidth for the device operating in the softening mode. By placing with the double attractive stationary magnets, the energy harvester shows the most effective softening non-linear system.

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Programmable Logic Controller (PLC) plays an important role as a part of control system to ensure production process in factories running properly. Consequently, many industries adopt this system as it can increase the production capacity rapidly. In this research, an auto feeder has been designed to replace existing manual operation of a door panel factory. The objective is clear since the factory is keen to increase its production capacity. However they have limited skillful operators. Inefficient, inaccurate and unsafe current manual operations system represents a significant burden for the company. This research utilizes PLC with CX-Programmer and Automation Studio Software to design and realize the mechanism. Simulation tests have been done and the results show that the designed control system works properly. Reliability test has also been conducted using additional Electro-Pneumatic Trainer. Analyses were carried out for performance comparisons of automation with existing manual system. Based on the results obtained, running time for automation system is 33 seconds, and an average of 42.8 seconds for manual operation. Final results of the research show a design of control system for Auto-feeder machine has been successfully created where about 15-20% of production capacity has been increased.

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It is important to study joint contact mechanics in order to understand the human joint function and degeneration. In previous studies, the cartilage behavior was investigated using computational method assuming the cartilage to be flat and an ideal thickness. But, this assumption may not appropriate because the joint is naturally curved and the cartilage thickness varies across the articular cartilage. In this study, finite element (FE) analysis was performed to investigate the effect of cartilage thickness on contact pressure and pore pressure of cartilage in indentation test. An axisymmetric FE model of cartilage was developed according to the thickness and radius measured in the experiment. The cartilage was modeled as biphasic material to describe the properties of cartilage. Based on the result, the lowest cartilage thickness of 0.3 mm thickness generated 48% higher in contact pressure and 59% higher in pore pressure, compared to the highest thickness cartilage. This could indicate that the cartilage thickness does affect the contact pressure and pore pressure.

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Dredging is a necessary procedure to remove unwanted sediments from the seabed. However, the material was disposed back to the sea. Some of the material was contaminated due to industrial waste, sewage runoff and agricultural discharge. Metals is inorganic pollutant which is undegradable and can be toxic to marine ecosystem. The aim of this study is to determine the metal concentration in the material and evaluate the degree of the contamination. Four dredged marine sediments samples were retrieved from Malaysian waters. X-ray fluoresnce was used to determine the metal concentration and contamination indices were used to evaluate the degree of contaminant of the material. There were six metals detected by x-ray fluorescene; As, Cr, Cu, Pb, Ni and Zn. Based on the contamination degree, all the dredged marine sediments were found to be considerably low degree contamination.

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Ambient vibrations from microtremor measurement were carried out in the University Tun Hussein Onn Malaysia (UTHM) using Lennartz 1Hz tri-axial seismometer sensor. Microtremor measurements have been conducted on 5 boreholes at UTHM, to study the correlation between the natural frequency (Fo) and depth of borehole. All of ambient vibration has been analyzed using Horizontal to vertical spectral ratio (HVSR) method introduced by Nakamura (1989), where the natural frequencies of the site were estimated from the single peak of HVSR in the North-South (NS) and East-West (EW) directions. The reliability of natural frequency (Fo) values are distributed between 1.18 to 1.78 Hz in the both of the directions. Meanwhile, the soil thickness was calculated in the range between 34.13 to 37.90 m using by Eq. 1.

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Recently, the techniques in geotechnical engineering design based on shear wave velocity measurement have had positive effects on the development of Spectral Analysis of Surface Wave (SASW) test. This SASW test has been shown to give reasonable results for in-situ measurements of shear wave velocity. In this study, the used of shear wave velocity and damping is being successfully applied to determine the ultimate pile bearing capacity. The method based on the viscoelasticity soil model proposed by (Abbiss, 1983) and the equation of the relationship between hyperbolic shear strain and shear stress suggested by (Hardin and Drnevich, 1972) has been used in this study. Further, the results from SASW and Instrumented Pile Load (IPLT) test that has been conducted at a site of residual soils located in Damansara, Selangor were compared. The results of the numerical calculation indicate that the percentage error in the ultimate pile bearing capacity is -1%, achieved the standard acceptance in the geotechnical engineering design.

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The early warning systems for flood management have been developed rapidly with growth of technologies. These warning systems help to alert the people earlier. Many proposed system used sophisticated techniques to alert flood such as Short Message Service (SMS) via Global System for Mobile communications (GSM), however, they are still complex to program and interface, in addition to their high cost. This paper proposed a simple, portable and low cost of early warning system using Arduino board, which is used to control the whole system and GSM shields to send and receive data. This work applies on study area in Taman Ira and Kampung Bakau, Kangar. The proposed model determines the water levels using ranging sensors. Then it analyses the collected data and determine the type of danger present. The GSM network is used to connect the overall system units via SMS. The system has been designed and implemented based on two components, hardware and software. The system units are powered from the rechargeable batteries. Two additional temperature sensor and humidity sensor also embedded as to relating the water level with the current temperature and humidity. The early data obtained by the SMS is used in determining the of flood impact toward the population by using the assessment table.

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A tsunami as long wave and an oscillatory wave moves into shoaling water have behavior similar to solitary wave and therefore comprehension on its bottom boundary layer characteristics come to be essential key on near-shore sediment transport modeling. In the present study, the hydraulics phenomena of solitary wave are studied in deep through experiments utilizing a closed conduit generation system. This result was examined by analytical and numerical laminar solution. Moreover, wave friction factor is discussed based on the present laboratory experiment and previous studies of (Sumer et al., 2010); (Vittory and Blondeaux, 2011, 2012). As conclusions, in-consistent critical Reynolds number was found for solitary wave case. This observable fact is distinct difference with sinusoidal wave case which has consistency in critical Reynolds number. As a main conclusion that a new generation system proposed in the present study will be able and applicable to shore up an experiment on sediment transport induced by solitary wave.

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Solidification/Stabilization is an effective, yet economic remediation technology to immobilize heavy metals in contaminated soils, sediments and sludges. The main objective of this research was to study the effect of replacing cement with rice husk ash (RHA) on compressive strength and leachability of Pb from the stabilized sediments. Cement and Rice husk ash were used as stabilizing agents to immobilise lead contaminated sediment. In this study, artificially contaminated sediment was prepared by spiking Pb(NO3)2 to achieve an average of 1000 ppm target concentration to bracket a worst case scenario. The Pb- impacted sediment was stabilized with 10% cement and 5, 10, 15 and 20% rice husk ash (RHA) by total dry weight of the mixture and was cured for 7, 14 and 28 days. The unconfined compressive strength test (UCS) and the toxicity characteristic leaching procedure (TCLP) was used to evaluate the effectiveness of the S/S treatments at 7, 14 and 28 days. The result of the Toxicity characteristic leaching procedure (TCLP) leaching test conducted on the lead spiked solidified samples indicated that with addition of 15% RHA at 7, and 14 days the Pb concentration was below the leachability limit of 5 mg/l, subsequent 28 days of curing, the concentration of lead was all below the leachability limits except the control sample. The effect of pH on the leachability of lead (Pb) was also considered in the study, the leachability of lead in the TCLP at 7, 14 and 28 days respectively decreases from 13.49 mg/l to 1.89 mg/l as the pH of the leachates increases from 3.57 - 5.13. It was also observed that the higher the strength of the solidified sample the lower the leaching rate of lead in the TCLP. The X-ray diffraction (XRD) results indicated that lead in Pb(NO3)2 had precipitated to form Pb(OH)2 within the cement hydration environment which explained the high treatment efficiency due to low solubility of the precipitates. Results have indicated that the partial replacement of cement with RHA in the binder system has increased the strength and reduced leachability of Lead from the treated sediment samples compared to the untreated ones.

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The impact of land uses can cause significant changes in the hydrological regime of a river basin. Sg. Pusu is a recent example in Malaysia, which is going through indiscriminate changes in the landuses. This study was conducted in response to the recent severe flash flood occurred on 4th June, 2014 due to high rainfall intensity of 82.4 mm/hr which lasted about 2 hours. The flooding depth varied from 0.3 to 1.0 m and the flash flood duration was about 1.5 hours. Although the duration was short but it damaged 12 cars, inundated 2 blocks of the hostels (Mahallah) and caused inconvenience to the staff and students of the campus. The drainage and river systems of the campus was functioning properly as the seven ponds and lakes constructed along the rivers and tributaries could reduce the peak flows coming from the upstream areas. However, due to improper land clearing from 2009 and onwards, the peak flows during the rain events have increased significantly, the lakes and ponds constructed by IIUM has silted up and lost their flow reduction ability. As a result the flash flood incidents have increased compared to the past records. The development activities in the upstream areas not only have increased the severity of flood in the campus but also caused sediment related water pollution turning the Sg. Pusu and its tributaries muddy all the time. Due to the improper land clearing activities in the upstream areas, the runoff peak flow and sediment load has increased tremendously, which the existing lakes, ponds, rivers, culverts and drainage system are unable to cope with. The river is also badly affected by the improper land clearing activities at the upstream areas. The Turbidity and TSS values at the river outlet during the dry day and rainy days are recorded as 1640 NTU and 1290 mg/L and 2510 NTU and 2400 mg/L, respectively. The aesthetic appeal of the river is very repelling due to high turbidity and muddy appearance of the river. As such, proper integrated river basin management with necessary supports from the people and authorities are badly needed to rehabilitate Sg. Pusu which flows through the IIUM Gombak Campus.

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Throughout the globe, there are various types of sustainable assessment such as LEEDS, BREEAM, HK-BEAM and ENERGY Star. In Malaysia, Green Building Index (GBI) is the authorized agency who works on sustainable assessment. Different sustainable agencies provide different methods, have different documentation procedures and generate reports. To leverage the current information technology in construction industry, BIM is introduced as one of the greatest tools to assist information sharing among construction players. BIM concept provides platform for information sharing and integration requirements by promoting interoperability between various applications. Thus this paper presents sustainability assessment methods by applying in a single framework.

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This paper presents the effect of kenaf fibre and steel fibre mixed and added into reinforced concrete beams. In investigating the structural behaviour of the beams, four-point bending tests were conducted on six beams by considering two distinct parameters; (i) shear reinforcement arrangement (ii) volume of fraction of kenaf fibre and steel fibre. The experimental work consists of six beams, three beams with full shear reinforcement added with fibres by a volume fraction of Vf = 0%, Vf = 1% and Vf = 2%, respectively. Whilst, the other three beams tested with a reduced amount of shear reinforcement added with fibres with a volume fraction of, Vf = 0, Vf = 1% and Vf = 2% were examined. The beam with Vf = 0% kenaf and steel fibre in full shear reinforcement was taken as the control beam. The experimental result suggests promising enhancement of the load carrying capacity (up to 29%) and ductility (up to 22%) as well as controlled crack propagation for the beams with Vf = 1%. Additionally, it was observed that addition of fibres changes the mode of failure of the beam from brittle to a more ductile manner.

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This paper presents damage inspection of reinforced concrete (RC) beam wrapped with carbon fibre sheet (CFS) using parameters of acoustic emission (AE) signals based on signals strength. RC is easily exposed to damage due to successive load. Hence, inspection of RC structures is vital to ensure the lifespan of the structure is fully controlled and safe. In doing so, experimental work on nine experiments on nine RC beams of 150 mm x 150 mm x 750 mm was carried out. The beam was subjected to three-point loading in conjunction with AE technique. Four AE sensors were set at selected position on the beam surface. The main aims of this study are to observe the crack propagation of the RC beam and to evaluate the crack development of control RC beam, RC beam wrapped with CFS in one layer and RC beam wrapped with CFS in two layers when subjected to increasing static loading. Three RC beams were statically loaded to failure and the remaining six beams were tested under increasing static loading. The increasing static loading were based on seven loading phases of 0.1Pult (Phase 1) to 0.7Pult (Phase 7). The inspection was based on the visual inspection of the crack development for each load phase and the relationship between signal strength and X-location. It is found that the signal strength against X-location generated good correlation for damage assessment of RC beam wrapped with CFS.

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The features of metrological calibration tests of surveying instruments, particularly digital levels are described. The procedures for investigating “digital level – barcode rod” system are offered that allow determining for a barcode-rod image scale. Such procedure can be used both in the laboratory of industrial company having digital levels and in the field conditions. The laboratory bench is also offered to determine basic specifications of levels with visual reading, “digital level – barcode rod” system, and total stations as well. The necessity for carrying out instrumentation calibration in the field is caused due to mechanical shocks of a digital level when transporting that can lead to the disadjustment of a level’s electronic system. As a result of this a barcode-rod image scale can be changed.

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Dredging work involves a range of marine soils, varying from coarse to fine, clean to contaminated. Dredging involves excavation and disposal and both processes could affect the marine environment through release of possible contaminants. Due to the potential for transmission of diseases, this hazard becomes a major concern as the Dredged Marine Soils (DMS) have its own values for reuse or recycle purposes. To prevent the needless cost and time involved in assessing several of pathogen bacteria, the indicator bacteria, Escherichia coli (E. coli) been used to assess the biological contamination in marine environment. The effect of natural factors, solar exposure and depth of soil were investigated. The main goal is to understand bacteria survival ability, as an approach to deal with the hazards. Under the condition without the existence of predatory microorganisms, experiments are performed at nine hours of solar exposure. In laboratory solar exposure experiments, the data dealing with the survival of bacteria showed that the cell reduction was more pronounced when compared to the absence of solar threat. After an extended period of solar exposures, as high as 90 - 99 % of E. coli have being removed.

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Pedestrian behaviour study has become a popular topic in transportation and planning conferences where many papers connected to the topic had been published. In Malaysia, studies on the effect of egress facilities, especially at the underground train stations towards the pedestrian movement during emergency evacuation have been given little attention. In order to assist the stakeholder in public transportation division, two shortcomings in the safety aspect of evacuation have been identified. Firstly, the pedestrians’ demand on egress facilities is excessive and could cause severe congestion during peak hours. Next, up to this date, Malaysian Government is yet to establish their very own standard or specification and manuals for emergency evacuation. Instead, they use internationally recognized NFPA 130 standards to construct underground space and facilities for pedestrian. The objective of this study is to identify the factor that influences pedestrians’ behaviour and to explain the framework used for analysing the simulation of risk perception based on it. Site observation and video recording of the passengers’ movement and standing at the platform during peak hour is used as measurement and data collection of this study. Next, questionnaires are used to identify passengers’ route choice in the event of emergency. Viswalk software tool is used to simulate the people’s movement in virtual environment before being validated using Emergency Response Plan (ERP). Significantly, this study will contribute new knowledge in managing passenger crowd during emergency situation towards rail industry in Malaysia (LRT, MRT) as well as academicians.

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This paper report result of a study conducted on fly ash lightweight aggregates (FALA) in foamed concrete cubes. The type of fly ash used is class C. The effects of using fly ash can be determine by its partial replacement of 5%, 10% and 15% in FALA. The effects of FALA can also be determine by its partial replacement in foamed concrete cubes of 25% and 50%. Three samples for each percentage is made to get the average readings. The test done divided into two which is on FALA and foamed concrete cubes. Among the test are density test, specific gravity test, water absorption test, scanning electron microscope (SEM) test, loading test and compression test. In conclusion for this paper report, the suitable percentage of fly ash that can be used for partial replacement in cement is 15% and 50% for partial replacement of FALA in coarse aggregates. This sample reach the density of 1.498 kg/m? that include in the lightweight aggregates category with the compression strength of 13.442 MPa.

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Research on energy absorption of metal has been conducted extensively over the years. Square, rectangular, circular, triangular and hexagonal shapes are the types of tubes that have been vastly investigated. The importance of this research is to measure and analyse the energy absorption characteristic of the manually fabricated tubes during impact. Axial crushing test is the most common experiment that is used to gain the energy absorption value. This report employed quasi-static axial crushing test. Square tubes, rectangular tubes, hexagonal tubes and triangular tubes were fabricated and joined by using zigzag MIG welding. From the experiment, it is found that hexagonal tube has the highest energy absorption value and triangular tubes had the lowest energy absorption value.

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Dredging is a process to excavate and remove sediments from the bottom of waterways and marine locations, such as ports and harbours. Dredging activities generate large volumes of dredged marine soils (DMS). DMS are the sediment and debris that were removed during the dredging process and are currently not being recycled. Solidification of DMS needs to be undertaken before the materials can be reused. Soil contamination has the potential to contaminate the ground and surface water through leachates that are produced from the contaminated sites. Synthetic precipitation leaching procedure (SPLP) was used in this study to predict contaminant leachability of the DMS. SPLP test was carried out for the solidified samples at different curing times i.e. 3, 7, 14, 28 and 56 days. It was found that the solidified DMS improved leachate properties of the DMS. Ordinary Portland cement (OPC) was used as a binder in this study and bottom ash (BA) used as granular admixture to solidified DMS. This gives further advantage to OPC-BA solidification of DMS in situ for the geo-environment perspective. Its shown that the solidified DMS can be used safely in actual construction field since it was not contaminated.

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Precise determination of engineering properties of soil is important for the proper design of any geotechnical structure. In general, the most common parameters used in computing strength of soil as currently being practiced are the cohesion (c), internal angle of friction, (F), and standard penetration test (SPT-N) values. These parameters are normally obtained from actual soil boring and extraction of samples which are then brought to the laboratory for the appropriate testing. However, bore hole drilling and sampling method is in general time consuming and very expensive and so this paper presents the results of an ongoing research on correlations of electrical resistivity with strength properties of soil with the long term objective of partially replacing soil boring with geophysical methods. Soil drilling, 1D field electrical resistivity (VES) and seismic survey and laboratory tests results were together analyzed to look into the behavior or correlations between electrical resistivity against various strength parameters. From the data obtained, the soil could be generally classified as sandy clay loam and results show that for this particular soil type, an increase in electrical resistivity produces higher angle of friction and lower cohesion with regression values of R2 = 0.5586 and R2 = 0.4693 respectively, while correlation between electrical resistivity and SPT-N depicts a polynomial curve having both increasing and downward with a regression value of R2 = 0.8399.

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Grassed swales are widely employed to encourage ground infiltration and reduce storm runoff in urban areas. Precipitation that infiltrated into surrounding soils is collected and conveyed by swales into nearby water bodies to prevent localized flooding. Swales are one of the means to decrease the velocity, to reduce the peak flows, and minimize the causes of flood. However, a well functioned swale requires a systematic planning of construction. This study presents the determination of flow velocity for grassed swale in University Tun Hussein Onn Malaysia (UTHM) and how its efficiency based upon the varied swale profile. Data collection was conducted on the grassed swale with the total length of swale is 100 meters. The swale is divided into three sections, where every section has three points. The measurements of flow velocity have been taken three times at each point after a rainfall event by using the current meter flow. As a preliminary work, levelling has been done on the swale beforehand to obtain the swale profile. The results showed various values of flow velocity according to the swale profile and its flow depth. The cross-sectional area of swale is in the range of 0.285 m2 to 0.496 m2. Meanwhile, the flow velocity observed from the swale is in the range of 0.027 m/s to 0.080 m/s. As a result, there are differences in flow discharge occurred, which in the range of 0.012 m3/s to 0.023 m3/s. An effective swale must have a suitable swale profile that could decrease the flow velocity and reduce the flow discharge of the swale.

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The rise of extensive research and development on the application of steel fibre inside concrete is a tremendous topic in the last few decades. The obvious benefits of adding steel fibre inside concrete can be seen from the improvement of the mechanical properties of steel fibre reinforced concrete (SFRC). The improvement of the mechanical properties can be seen easily on the higher value of tensile and flexural strengths for SFRC compared to plain concrete. However, a question arises on to what extent does the steel fibre exerts an additional stress to increase the strength. Currently, this additional stress is called “shear stress supplement”. In this study, shear supplement model developed by Rilem was quantified with some statistical modification to predict the additional shear exerted by the steel fibre when it is placed inside the concrete. To achieve the objective, 51 prism specimens (150 mm × 150 mm × 750 mm) were prepared and differ in terms of the type of steel fibre and the fibre volume fraction, Vf. Two types of hooked-end steel fibre labeled as SF60 and SF50 were used in this research. Meanwhile, each type of steel fibre was mixed into a plain concrete with respect to the Vf of 0.25%, 0.50%, 0.75%, 1.00%, 1.25%, 1.50%, 1.75%, and 2.00%. Plain concrete prisms were prepared as the control specimens. After 28 days of curing period, the prism was then transferred to the test frame to undergo flexural strength test. The results from the flexural strength test were used to develop the shear stress equation to predict the contribution of steel fibre to increase the shear stress. The modified equation was then used to predict the value of shear stress supplement. The results showed that, the modified model well predicted the shear stress supplied by the steel fibres well which was shown by higher coefficient of correlation.

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In reinforced concrete design, the consideration of the characteristic strength of concrete is not theoretically determine and it is based on the experience of the designer with respect to some theoretical on the design background. Therefore, it may lead to produce ineffective design that produce high volume of material due to over-designed product. Highly cost designed will be produced due to this problem. Currently, align with the consistently in the environmental issues awareness, an impact assessment has been recognized as main key factor to encounter the problems. Therefore, it is necessary to proposed new solution that is simultaneously compliment the cost and environmental impact in the choosing the most sustainable design. This study proposed and integrated model for assessing cost and CO2 emission that lead to produced eco-efficiency design of reinforced concrete structure for Malaysian construction practice. The eco-efficiency design is determine by two parameter which is economic score and environmental score that is based in Malaysian practice. Therefore, the proposed eco-efficiency design model will be adopted as the decision-making process method in selecting the best sustainable design for reinforced concrete structure.

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This study presented experimental results on the use of ceramic waste as substitutes in the composition of laterite soil compressed bricks, better known as compressed earth brick (CEB). The use of ceramic waste was chosen because in recent years it can be seen landfills can no longer accommodate the growing of solid waste. Some examples of solid waste are glass, cans, plastic, paper and ceramic waste. Ceramics used in this study are ceramic rest that has been broken taken from the landfill and then crushed before mixing with the mixture of CEB. The main objective of this study was to investigate the physical and mechanical properties of compressed earth bricks containing waste ceramics and to determine the optimum percentage of waste ceramic in any mix of revenue compressed earth bricks. A total of 72 units of bricks were produced and used to test the density, water absorption, compressive strength and the initial rate absorption. The sample size utilize prototypes size of 100 mm x 50 mm x 40 mm. Laboratory tests conducted in accordance with the test procedures that were performed on brick CEB as specified in BS 3921: 1985 and MS 76: 1972. The experimental results shows that the ratio of ceramic waste 75% was the optimum value because it recorded the highest compressive strength with 33.6 N/mm2 and the test of water absorption and initial rate absorption test were 17.2% and 1,634 kg / min / m2 respectively.

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The study was conducted to investigate the physical properties of African pear seeds, the flesh African pear seed was purchased from Ojo market in Ibadan and mesocarps of the fruits were removed to obtain the nuts. The nuts were dried under ambient conditions for several days, the actual moisture content of the nuts at the time of experimentation was determined, using KT100S Moisture Meter with measuring range of 5-35% to be 21.50%. The nuts were sorted into three grades: small, medium and large, based on the visual physical assessment of their sizes. The three principal axial dimensions of 250 nuts from each grade were measured using a vernier caliper. In this study some selected physical properties of African pear seeds were determined which are essential for designing engineering processes, material handling, storage, equipment design and fabrication. The physical properties, namely, arithmetic mean diameter, geometric mean diameter, surface area, sphericity, aspect ratio, true density and bulk density were determined. Also, angle of repose and coefficient of friction were tested on mild steel, plywood and PVC plastic which are probable engineering materials for construction of food processing equipment. The results revealed that average geometric mean diameters of the nuts are 25.22, 30.74 and 35.26 mm for the small, medium and large size grades respectively. The nuts are fairly ellipse with average sphericity of 0.54, 0.54 and 0.59 for the small, medium and large size grades respectively while true and bulk density0.96 g/cm3 and 1.14 g/cm3 respectively. The angles of repose were 40.99, 47.92 and 47.53 small, medium and large size respectively. These findings can provide the information that could be helpful for development of mechanical expeller or processing machines.

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Uncontrolled vibrations can leave a bad impression to the machine, structure, and human. For example, vibration on machine can damage the equipment, decrease the machine lifetime and also causing the safety factor problems. Therefore, a vibration absorber is obliged to reduce these vibrations. The present paper investigated a new design of tuned vibration absorber (TVA). The proposed TVA is: (1) light in weight and small in scale, which suitable for mobility purpose, and (2) can addressed a broad frequency range of application. However in this paper, the effectiveness of new design of TVA to reduce the vibration is not covered since the TVA has been proved in the previous study being able to reduce the vibration significantly. The frequency range of absorber was determined through finite element analysis (FEA) and validated with the experimental result. The aim is to enhance the range of frequency that TVA can tune from 0 to 1000 Hz. In order to generate the result, SolidWorks® software was used in the finite element analysis and DEW soft equipment was used in experiment. The results in the finite element analysis showed that the maximum frequency that TVA can tune is 800 Hz while from experiment is 980 Hz in the experimental analysis. Although there is an error about 18% between FEA and experiment, the findings are still significant because the maximum frequency of the new design TVA can reach is approximate to 1000 Hz. This study concludes that the new design of TVA which is small in scale and light in weight is able to reduce the structural vibration extensively if it is tuned correctly to the targeted frequency range of 0 to 980 Hz.

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Due to its properties of high wear, creep resistance, high stiffness and strength, Ultra-High Molecular Weight Polyethylene (UHMWPE) was developed to eliminate most metallic wear in artificial implant, which conventionally found in stainless steel, Cobalt Chromium (Co-Cr) and Titanium (Ti) alloys. UHMWPE has an ultra-high viscosity that renders continuous melt-state processes including one of the additive manufacturing processes, Fused Deposition Modeling (FDM) ineffective for making UHMWPE implant. Attempt to overcome this problem and adapting this material to FDM is by blending UHMWPE with other polyethylene including High Density Polyethylene (HDPE) and Polyethylene-Glycol (PEG) which provide adequate mechanical properties for biomedical application along with the improvement in extrudability. It was demonstrated that the inclusion of 60% HDPE fraction has improved the flowability of UHMWPE in MFI test and showing adequate thermal stability in TGA.

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Green production in industries has been increasing significantly in the last few years in Malaysia and now is considered to be a mainstream challenge for organizations. In addition, the awareness is due to several factors including sustainability of the company as well as a green policy introduced by the government. Green manufacturing is considered as a form of cleaner production processes with optimization approach. However, studies related to green manufacturing practices are still insufficient because of unexposed to green technologies in production and low employee commitment. To address the gap, this study focuses on the factors involved in green production performance from Malaysia context. The two factors are worker involvement and cleaner production that significantly reported to have positive impact on green production performance. The companies selected are among electric and electronic manufacturer with ISO 14000 environment management systems and standards, waste electrical and electronic equipment in Johor as the basic criteria for the implementation of green practices. The study employed survey method adapted from previous studies and respondents were among the production engineers, managers and quality assurance personnel. The total sample size is 90 respondents. The study provides the scale to measure green practices and tested two developed hypotheses. The study confirmed cleaner production factor is the most influential factor with 61.2% of the factor explained the influence on green production performance compared with worker involvement factor (60.6%). Hence, the company should set the stage for cleaner production activities, in order to ensure collaboration and participation from the workers. Future research should include different sectors to enable comparative studies. A larger sample would also allow a detailed cross-sector comparison.

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Supply Chain is one of the stages of product lifecycle. This process evolves day by day through connected with other process of product development. The improvement of supply chain involve in many ways so that the effectiveness can be improve by minimizing time and cost. Sustainability is important issue need to be considered in supply chain process. Through sustainability, the environment, social and economic become the issues that can be further improved. There are a lot of factors in these three aspects of sustainability can be influence the process of supply chain by identifying and managing those factors in the design phase. However, the current technique of design phase did not give a lot of attention on sustainability issues in the supply chain that may effect the time and cost in product development process. Through this paper, a review of literature including a total design as a design model, supply chain and other supporting models and techniques will be discussed in order to integrate of sustainability, supply chain and design phase. This paper at the end prepare the general framework which will give a brief picture of integration the design phase and supply chain for this research in the development of score metrics for supply chain sustainability.

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This paper describes the analysis on the sound absorption characteristics of semi-permeable membrane absorber. The effects of membrane surface tension and backed-air gap distance on the sound absorption characteristics were investigated. The characteristics of the membrane absorber were measured experimentally in terms of Sound Absorption Coefficient, a and Noise Reduction Coefficient, NRC. The membrane is made of a thin, flexible, semi-permeable latex material and the tests were carried out by using impedance tube method according to ISO 10534-2 standard. The results showed that the surface tension has significant influence on the sound absorption characteristics. For the parameters used in the laboratory work, the specimen with un-stretched surface tension has the best absorption performance with 94% absorption at 1600 Hz. Membrane absorbers showed best performance at low-middle frequency region i.e. 1450-2000 Hz. The backed-air gap distances determine the location of sound absorption peak. The peak of absorption tends to shift to the lower frequency region when the air gap thickness is increased.

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Efficiency of combustions engine is highly dependent on the formation of the air-fuel mixture prior to ignition. Both the homogeneity of the combustion process and the ignition process are largely dependent on the mixture properties. This study focuses on determining the spray characteristics of biodiesel blend in rapid compressions machine (RCM) by using simulation of ANSYS version 15.0 Fluent. The parameters investigated including spray angle, spray penetration, spray velocity, size diameter of particle, formations of spray, turbulence kinetics energy and spray area. The simulation was performed on three types of biodiesel blend which are B5, B10 and B15 at different ambient pressure and ambient density. Result shows that when in high ambient pressure, the spray of biodiesel angle decreased. The results also indicated that, the spray penetration length and spray area decreased with the increasing in the ambient density. The spray velocity also decreases as the ambient density increases. This study concludes that the ambient pressure and density strongly affected the characteristics of fuel spray.

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System identification has been widely used in modelling dynamic system whereby the input-output data from real system are undergo the model structure selection, parameter estimation and model validation procedure. However, the most complicated part in modelling the dynamic system is selecting the model structure to represent the system. In this project, bee algorithm (BA) is integrated with system identification technique to optimize the model structure selection in modelling the dynamic system. This project describes the procedure and investigates the performance and effectiveness of BA based on a few case studies. The result indicates that the proposed algorithm is able to select the model structure of a system successfully. The validation test carried out demonstrates that BA is capable of producing adequate and parsimonious models effectively.

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Cortical bone fracture that caused by stress amplification effect is hypothesized to initiate and amplify by the existence of co-planar macro and micro cracks interaction. The amplified crack interactions within the human cortical bone are quite complicated to investigate because of the bone microstructure. At the microstructure level of bone, it is clear that every particle of the bone is essential in protecting the bone from fracturing. This paper aims to investigate the stress amplification effect of the stress intensity factor (SIF), based on stress singularity located at the crack tips. Finite element models of two coplanar edge cracks for different crack distance and crack interval are developed based continuum mechanics theory and linear elastif fracture mechanics (LEFM) assumption. The SIF value accuracy is based on the developed singularity element around the crack tip. The result showed that the SIF of both coplanar cracks are exibit the different trend for Mode I and II. Moreover, the existence of crack interaction limit (CIL) and crack unification limit (CUL) have proved the theory of interacting cracks.

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