Fourier transform infrared (FTIR) spectroscopy studies of poly (vinyl) chloride (PVC), doped with ammonium trifluoro methane sulfonate (NH4CF3SO3) salt and ionic liquid (IL) butyltrimethyl ammonium bis (trifluoromethyl sulfonyl) imide (Bu3MeNTf2N) were synthesized via solution cast technique. About 50 ml of tetrahydrafuran (THF) was used as the solvent. Interaction between the polymer, salt and ionic liquid (Bu3MeNTf2N) was confirmed by FTIR spectroscopy. FTIR spectra revealed that Bu3MeNTf2N has weak interaction which suggesting that it acts mainly as a lubricant to facilitate polymer segmental motion.

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Schiff base derived from N-phenyl-1,4-phenylenediamine (NPPD) have been synthesized and studied using X-ray photoelectron spectroscopy (XPS). The binding energies in XPS agree very well with elemental analysis of the studied compound. The results confirmed presence of C=N bond in Schiff base ligands and the presence of Cl 2p in (E)-N1-(4-chlorobenzylidene)-N4-phenylbenzene-1,4-diamine (K2).

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Theoretical studies on six thiourea derivatives - C6H5(CO)-N-CS-N-C6H4X (where X = H, Cl, Br, NO2, CH3 or OCH3 located at the para position) have been made for a single molecule. By employing the Density Functional Theory at the B3LYP level for a single molecule, it shows that all the compounds have a rotational barrier at the thiourea moiety caused by the intra-molecular hydrogen bond that forms a pseudo-six-membered ring C2-N3-C5-O6---H-N4. Optimized parameters agree well with the experimental data. The general trend observed for the parameters of the optimized geometry for all compounds is influenced by the electronic properties of the substituent on the phenyl ring. The highest occupied molecular orbital (HOMO) and Lowest unoccupied molecular orbital (LUMO) characteristics, hardness and electro negativity are closely related to the electronic properties of the substituent group. Harmonic oscillator model of electron delocalization (HOMED) analysis provides that aromaticity is influenced by electronic properties of substituent group.

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This paper presents an innovative design of a prototype TudungSaji that involves both hardware and software development. This project is designed an effective TudungSaji is able to maintain the food warm and to protect food from pests like flies and rats. Smart TudungSaji uses an Arduino microcontroller to produce an automated function. The main parts of this project consist of chassis, 2 sensors which are temperature sensor LM35 and limit switch sensor as an inputs, the ATmega328p microcontroller and 2 bulbs as an outputs. This is to ensure the warming process operates more efficiently and effectively. The algorithm is developed and implemented with Arduino Uno. It is really practical for human, especially working woman to make their life simpler. This project helps people to keep their food warm and it is portable to bring anywhere. The performance of this project was validated with the simulation circuit using Proteus 6 Lite, and the results and findings from conducting experiments on the prototype. The bulbs are activated by the LM35 sensor detected temperature below 60oC.Then, the bulbs will automatically off when temperature reaches upper 60oC.This project uses 240V 100W bulb as a heating element. It can be improvised by replacing bulbs with thermistor coil. The thermistor coil can produce more heat energy because of the material of the coil, for example in the oven.

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In this study, azido-terminated poly (?-caprolactone) (N3-PCL) was used to attach the macromolecules poly (?-caprolactone) onto graphene sheets to give functionalized graphene (G-PCL) that can increase the solubility of graphene sheets. The key of the reaction is nitrene chemistry. Double bonds in graphene were being attacked by high reactivity nitrene radicals from azido groups to form covalent bonds of C-N. Most reported papers showed the grafting-on functionalization based on graphene oxide. On the contrary, we reported grafting-on functionalization using pristine graphene.The attachment of PCL macromolecules onto graphene sheets was determined using transmission electron microscope (TEM), thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) and solubility test using several solvents. TEM showed PCL coating onto graphene layers. PCL macromolecules content in the G-PCL was estimated about ~47%. Another relevant proof of the successful functionalization of G-PCL was using FTIR where the stretching vibration of azide group was completely vanished after the reaction due to the formation of C-N covalent bonds. The solubility of G-PCL was improved tremendously, especially in dichloromethane. Solubilization of graphene can open the door to various applications. G-PCL is expected to enhance the usage of nanomaterials in biomedical materials, biomedical engineering and materials for drug delivery system. The nanomaterials are likely to show a combination of beneficial properties.

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The aim of the study was to determine the suitability and properties of scarf joint for the species oil palm trunk (OPT) (Elaeisguineensis) and Kelempayan (Neolamarckiacadamba). It has been tested on different scarf cutting scarf joint angles such as 30o, 45o and 60oand uses a type of polyvinyl acetate adhesive of both species. The samples were tested using the method of bending and compression. The results of this study show an angle of 30o species of OPT and Kelempayan is the strongest compared to an angle of 45o and 60o for the bending test. When comparing the two species of OPT and Kelempayan, OPT is stronger than Kelempayan. For the compression test, the angle 60o is more resistant than an angle of 30o and 45o for both species. Therefore, the scarf joint angle 30o and 60o is suitable for use by industry because it is more resistant compared to the other angles. It can be concluded that species OPT (Elaeisguineensis) and Kelempayan (Neolamarckiacadamba) can be utilized for scarf joint in the production of furniture by using the appropriate scarf joint angle and furniture that want to produce.

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Cellulose has many advantages such as abundant in nature, inexhaustible, low cost, easy processing, renewable, biodegradable and biocompatible. The most interesting effect is its positive environmental impact. It is also a renewable resource whose further production requires little energy. Thus, more eco-friendly method needs to be used to extract the cellulose. Pineapple leaf and kapok fiber are chosen in this study, since both reported to have a high composition of cellulose. In this study, extraction and characterization were carried out to obtain pure cellulose fiber from pineapple leaf (Annanus cosomus) and kapok (Ceiba Pentandra (L.)) using eco-friendly method namely as dissolution in deep eutectic solvent (DES), which compose from choline chloride and urea. Chemical analysis and physico-chemical characteristics of raw and produced materials were investigated with the help of Fourier transform infrared (FTIR) spectroscopy and thermo gravimetric analysis (TGA). The FTIR results show that the treatment by dissolution in DES method removed most of the hemicelluloses and lignin from the raw pineapple leaf and kapok fiber. Chemical analysis also showed that 83.5% and 53.4% of cellulose contains in raw fiber of pineapple and kapok respectively. Meanwhile, the extracted fiber of pineapple and kapok containing 97.7% and 92.1% of cellulose respectively. TGA demonstrated that cellulose extracted from dissolution in DES method has higher thermal stability compared to raw fiber. Obtaining pure cellulose from natural fiber, including pineapple and kapok fiber is essential due to its potential in various applications.

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Heat treatment is one of the preferred methods in altering material characteristic. In this present study, the effect of austenitizing temperature in double-quenching heat treatment process was studied on microstructure as well as exploring the phase constituents of ductile iron through x-ray diffraction (XRD)analysis.Ductile iron produced through conventional CO2 sand casting method. Ductile iron was heat treated by using the double-quenching method. The sample was annealed at 673K for 1.8 ks and subsequently oil quenched before austenitized at 3 different temperatures which those are 1123K, 1173K and 1223K for 3.6 ks respectively. Standard metallographic observation nodule and XRD analysis were done to characterize the microstructure and the constituents respectively. It is found that austenitizing process transforms the microstructure from pearlitic-ferritic matrix structure, which presented in annealing condition into martens tic. Marten site morphology becomes coarser and the nodularity of graphite nodule decreases as austenitizing temperature increases. But, austenitizing process seemingly gives no significant effect to the graphite nodule size. The presence of BCT marten site is validated by the presence of high-intensity (110) and (101) planes verified at 430 to 440 2? angles. Austenitizing sub-process of double-quenching heat treatment process does influence the marten site and graphite nodule morphologies. It transforms ferritic-pearlitic structure in as annealed ductile iron to martens tic matrix structure. The presence of Marten site and austenite can be validated by using XRD method with specific plane.

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The objectives of this paper are to study of characterization of bio-foam composite mixture of kenaf (Lignocelluloses natural fiber). In this study, kenaf have been produced as a kenaf polymer composite (KPC) mixed with polymer resin namely polyurethane (PU). The target density for the KPC is 200kg/m3. The kenaf fiber composition in the KPC is prepared in seven different filler percentages which are 0/100, 5/95, 10/90, 15/85, 20/80, 25/75 and 30/70%wt of kenaf fiber resin/composite binder. The composite sample was tested for its mechanical properties through compression, density and porosity test.The optimal percentage of kenaf fiber content should be less than 30wt% to get the best result on mechanical properties, where higher than that the natural fiber becomes less absorbed and the inner structure is clogged with the filler content. Based on the result of this research, the improvement could be done by add the temperature during experiment, structure cladding with other types of fiber particle concrete, sample prepared with different resin and below high pressure to obtain high density value and different surface of shape wall panel such as triangle or dwi flat.

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The study was investigating the velocity dissipation process of Avicennia marina and Rhizophora apiculata mangrove species by focusing on the root geometrical properties and the water flow structure within the root area. The root properties were investigated by conducting a field work. Hence, a model of the mangrove roots was constructed using the meshing software. The simulations were conducted in Computational Fluid Dynamic (CFD) software using unsteady Spalart-Allmaras turbulence model with water liquid material and by setting the velocity inlet in boundary condition to 6 m/s. It had been observed that mangrove root properties and coordination had a high influence to the flow velocity reduction. An area that had high roots densities and cross-section diameters were capable of dissipating more velocities, especially within the distance 100 cm to 150 cm from the primary trunk. The study also discovered that the contact between jets, eddies, turbulence scale and stagnation areas were contributing to the velocity deficit. The simulation result shows that mangrove roots of both species were capable of decreasing the initial velocity 6 m/s of water flow to almost 2 m/s. The flow velocity dissipation rate and flow structure in the mangrove root area found through this study will provide valuable data in increasing the efficiency of current breakwater models.

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Irrigation canals of the Saratov region during operation are exposed to overgrowing with trees and shrubs and the formation of soil drifts and bottom sediments. Removal of soil drift and bottom sediments from the bed of irrigation canals with the help of the existing milling working tools of reclamation machines is not always possible, so it became necessary to conduct a study on the creation of smaller end mills with more functional capabilities. Theoretical studies have been conducted to determine the dependence of the energy intensity of the process of cutting and earth handling on the geometric and kinematic work process-related parameters of the face milling cutter, physical and mechanical properties of soil sediments and operational parameters of the reclamation machine on the whole. The optimal value of feed and rotary speed milling cutter, leading to a reduction in capacity, energy intensity of earth cutting with knives and its subsequent handling with blades, increasing operation productivity of reclamation machine in general have been fixed.

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The main goal of the Russian O&G sector is to raise the oil recovery factor (ORF) through developing new and improving existing technologies of enhanced oil recovery. Among the latter, most efficient are physicochemical methods for the formation stimulation based on the use of different types of surfactants. Surfactants incorporated in chemical formulations bring about efficient residual oil displacement after flooding due to the ultra low oil/water interfacial tension and a change in the capillary number. According to a few studies the best effect in residual oil recovery was achieved with the formulations comprised of different types of surfactants. When mixed, such surfactants exert synergistic effects on the reagent’s surface activity, its rheology and behavior in the variable formation conditions. This paper discusses lab test results related to the impact of the size of compound micelles comprised of a mixture of anionic surfactants sourced from low quality hydrocarbon and nonionic surfactants on efficiency of residual oil displacement in high water cut wells. It has been proven that varying of the anionic/nonionic surfactant proportion in the mixture influences dramatically the size of the formed micelles, their interfacial activity, and efficiency of high viscosity oil displacement.

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The paper presents a brief overview of the existing solutions for connecting the rigid joints with the steel frame columns in multi-storied buildings, the advantages and disadvantages of the existing designs of rigid connection are analyzed; on the basis of the analysis performed a new structural design of beam to column connection with the use of the high-strength beam and pre-stressing of the near-support girder segment is suggested. A high-strength tie with pre-stressing creates in a girder opposite torques in the step and span girder zones and is also involved in transfer of the support moment from girder to the column. The paper presents the comparison of the metal consumption for a steel frame containing different longitudinal beam to column joints, the area of application of the new joint structural design has been specified; it was also shown that as the result of using the high-strength tie one may reduce the beam cross-section and reduce the metal consumption per a building frame.

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A promising way to improve the repair of complex geographically distributed technical systems (GDTS), organized on the industrial production, resource extraction bases, is the creation of repair and complex (RDC). RDC generally includes in its membership sites operational monitoring, diagnostics of components used in GDTS, as well as sites equipped with the necessary technological equipment, measuring tools, instruments and tools for maintenance replacement elements (RE). To ensure the repair, RDF equipped with a means of power supply, spare equipment and accessories (SEA) and operational documentation. It is assumed that personnel carrying out repairs have the appropriate expertise. Analysis of the functioning of such RDC is actual problem for many technological spheres. The most frequently RDC can be represented by a network of queuing network (QN). The study of such system with distribution functions of service time other than exponential complicates the use of analytical models, so the most effective is the use of simulation methods. The article presents basic principles of creating models of complex systems and discusses aspects of a structured approach to the simulation of such systems. The developed software implementation two RDC models allows us to simulate the process of its functioning with followed assessment of characteristics, the most important of which is the average time to service requests in the system, and determine the number of channels necessary on each of the sites. The model also provides the ability to use beta-distribution as a priory to set the values of duration of work and some other random distributions. The developed model can be aggregated into the overall research model processes operating GDTS. The software tool is implemented in an object oriented programming language C# with using an integrated development environment (IDE) software Microsoft Visual Studio 2010.

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In article is considered questions of application of indistinct neural networks for the solution of a wide class of the tasks connected with forecasting in difficult systems of a road complex. The offered concept considers nonlinearity of change of the majority of the processes proceeding in a road complex and influence of conditions of uncertainty. As examples of use of indistinct neural networks in a road complex results of forecasting of quantity of road accidents, managements of a transport and operational condition of highways and optimization of placement of asphalt concrete factories are presented.

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This paper presents the new approach to the physical and chemical analysis of formaldehyde absorption process on which basis possibility to propose the new more cost-effective technology based on efficient use of resources and power saving occurs. According to authors, the major way of process control over formaldehyde absorption is a liquid temperature stage control that provides grounds for the further researches. The paper is devoted to research of principles of the mechanism and kinetics of the physical and chemical processes proceeding upon formaldehyde absorption in the presence of methanol with the further preconditions on development of more effective way of formaldehyde absorption.

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Among the metals based on homonuclear chemical compounds of d-elements Ti, Zr and Hf (4-?? group of D. I. Mendeleev's periodic system) the choice of titanium as a primary structural material is justified for the manufacture of a reversible reciprocating electric machine translator with the capacity of 10-20 kW operating in harsh environments. This is due to the fact that the increase of metallicity degree of their homonuclear bonds Me---Me in the row titanium - zirconium - hafnium increases the density (?) at a slight change of the thermal conductivity (?), with a simultaneous decrease of thermal expansion ratio - TER (a•106). Thus, the first property provides the possibility for the manufacture of lightweight parts and units for the assembly of a reversible reciprocating electric machine translator, which has a sufficiently high refractoriness (Tm. = 1668 °C) and corrosion resistance, especially taking into account the presence of a protective oxide film on titanium surface with very close TER.

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This article describes an anthropomorphic gripper with a lever drive. Such gripper is a significant part of an anthropomorphic robot and is focused on performing operations similar to a human hand. Main gripper characteristics breakdown has been performed, optimal device parameters have been chosen. A combined type anthropomorphic gripper with a motion transfer system on the basis of lever mechanisms with use of group actuator and kinematic motion dependence of links of executive group has been developed. Importance of application of the principle of possible movements of application force points in the analysis of anthropomorphic gripper elements are stated and proved.

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The paper discusses the different uses of anthropomorphic robots to meet the challenges of the Moon by human. It showed great potential of using such robots: to ensure the safety of astronauts, servicing a wide range of space objects, solving research problems in a non-deterministic environment. In the formulation's part for the selection of specific embodiments of robotic systems are invited to consider the transport and manipulator’s tasks separately. This formulation has allowed more specifically set goals for robotic systems and to synthesize their various combinations in the optimized composition. Authors identified the most important problems of control systems development for space anthropomorphic robot; in particular, questions of inclusion in the robot control loop a human brain in relation to the lunar environment - in a copying robot mode on the lunar surface with the use of the remote operator and the exoskeleton. In addition, authors touched on learning and adaptation of the anthropomorphic robot. The article proposed the concept of the use of anthropomorphic robots on the lunar surface, which takes into account the expected dynamics of the lunar infrastructure and manned lunar base.

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High demand of L-asparaginase urges the researchers to maximize the production of this enzyme with affordable cost in short period of time. Microbial fermentation is an alternative source for production of L-asparaginase enzyme due to its low cost, easy culturing techniques as well as efficient purification. Addition of substrate is in favor to maximize the production of L-asparaginase where this substrate can be in the form of natural substance or waste products. Excessive amount of waste may cause environmental pollution. Thus, by utilizing waste as substrate is beneficial because the amount of waste can be reduced greaty. This study has shown that both cooked chicken bone and Moringa oleifera seeds as food waste and natural substance respectively can be used to enhance the production of this enzyme which involves fermentation.

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This work investigates the properties of glow curve of lithium Strontium borate doped sliver glass (LSBO: Ag), subjected to Co-60 gamma irradiation. The glass samples were prepared in different compositions based on 15%Li2CO3+2%SrCO3 (83-x) H3BO3 +xAgNO3, where x = 0.001, 0.003, 0.005, 0.007, 0.009 and 0.01 mol% by traditional melting quenching method at temperature 1300 oC for 1 hour. The structural pattern of glass samples has been identified by X-ray diffraction. The XRD pattern shows that the samples are glasses since there is broader peak appearing in the spectral pattern. FESEM images verify the homogeneous and transmitting surface morphology of all samples. Stable glasses with Hurby parameter ~ 0.5 are achieved. EDX spectra determine the accurate elemental compositions in the samples. Physical properties are determined in terms of glass density, molar volume, polar on radius, inter-nuclear distance, and ion concentration. Glass density is found to increase from 2.45 to 2.46 g cm–1 after addition of AgNO3 concentration. The TL intensity at different compositions of lithium borate doped sliver glass after exposed to 50 Gy Co-60 gamma-rays is presented. The results clearly show that the highest TL intensity is found in glass composition of 0.09 mol% of AgNO3.

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Tooth decay is considered the most widespread infectious disease in the world. This study aims to isolate and identify the important bacteria related to tooth decay, determine the sensitivity of bacteria in certain types of antimicrobial agents, and study the effect of heavy metals and virulence factors on bacterial isolates. A total of 50 swabs were collected from the mouths of patients from both gender, with ages ranging from 1–60 years. Results showed that infection rates in younger age groups (1–20 and 20–40) are higher than the elder group (40–60), with percent incidence of 44% and 32%, respectively. In addition, 100% resistance was recorded against seven heavy metals, including silver nitrate, iron chloride, zinc chloride, and lead acetate. The sensitivity to mercury, cadmium, and copper sulfate were 100%, 86.44%, and 1.69%, respectively. Hemolysin had the highest ability to produce virulence factors (72.88%), followed by lecithinase (42.37%) and protease (25.42%). Lipase and urease had the lowest virulence factor production (10.16%).

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Silicon nitride thin film is produced by radio frequency (R.F) Magnetron sputtering technique as an alternative to familiar chemical vapor deposition (CVD) technology. Rather than the conventional sputtering deposition parameters (i.e. R. F. power, sputtering gas pressure and sputter gas flow rate), in this work, the influence of distance between target to substrate was investigated. Experimental results show that target to substrate distance has a significant effect on growth rate and surface morphology of deposited thin films. Silicon nitride films deposited at target to substrate distance of 14 cm show the minimum surface roughness of 0.7 nm and high average transmission of 95% in the visible range. The deposited films exhibit the amorphous nature when characterized through XRD technique. The transparency of silicon nitride thin films in visible region points out its potential as an optical waveguide.

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Three dimensional cell cultures are receiving increasing scientific attention recently because of the biological similarity and relevancy to the in-vivo system. Further understanding on the responses of the micro tissues to the change of culture environment is lacking. In this paper, micro tissues of keratinocytes or keratin spheroids were cultured using the liquid crystal based 3D culture technique. The study was undertaken to investigate the behavior of micro tissues on both the liquid crystal surface and culture dish. Trypan blue exclusion assay and live/dead cell assay kit were applied to study the viability of the cells. The production of the micro tissues on RPMI-1640 and DMEM culture media were also studied. The micro tissues transferred to a tissue culture treated dish were found spreading into monolayer while the micro tissues on the liquid crystal substrate merged into larger piece of micro tissues. The trypan blue exclusion assay showed > 80 % of cell viability which agreed with the micro tissue transfer results and cell staining with Calcein Am and Ethidium Homodimer-1. The 3D cell culture in DMEM media having higher concentration of nutrients yielded higher (p < 0.05, t-test) number of micro tissues compared with RPMI-1640 culture from Day 2 of culture. Nonetheless, micro tissues migrated synchronously and merged into larger mass on the liquid crystal substrate. The physical properties of the micro tissues produced are highly influenced by the culture environment.

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Non parametric inferential statistics was used to guide the numerical optimization study to search for the optimum result in this article. The technique was demonstrated in a case study and a significant improved predictive model was formulated with 4% less residual sum of squares (RSS) than the median model, 20% less than the mean model and 79% less than a benchmarked empirical model. The methodology proposed herewith addressed the selection dilemma between mean and median. It identified an optimum value and formulated a better predictive model than those by either mean or median.

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Graphene oxide was prepared by the Hummers’ method and then electrochemically reduced to produce graphene nanosheets. Physicochemical characterizations were performed using XRD, FTIR, FESEM, TEM, Raman and UV-Vis techniques to elucidate the structure and morphology of the prepared material. The electrochemical study had been conducted on graphene by cyclic voltammetry, galvanostatic charge-discharge and impedance measurements, indicating its superb energy storage properties. The specific capacitance of graphene was 131 F g-1 at 0.1 A g-1. Impedance spectra showed low resistance of electrochemically produced graphene, supporting its suitability for energy storage applications, such as supercapacitor.

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Mathematical modeling of the spinning process is crucial for a better understanding of the process variables and process functionality in membrane development. Due to the broad use and key importance of mathematical models in chemical process engineering, experimental design is becoming essential for the rapid development and validation of these empirical models. This work used the design of experiment methodology and aimed to predict the performance of ultrafiltration systems for water treatment by considering the statistical regression technique as an important approach for modeling flux. The utilization of regression modeling was also explored to show the principle elements for predicting flux in the spinning process. In order to investigate how proficient the statistical regression technique is at approximating the predicted value for flux, a real spinning experiment was conducted in this study. In this experiment, 30 samples of data were collected based on a half fractional factorial experiment with design resolution V, as well as 4 replications of center points and 10 axial points. The spinning factors that were investigated are the dope extrusion rate, air gap length, coagulation bath temperature, bore fluid ratio, and post-treatment time for predicting the corresponding flux. The regression model obtained shows that there is a correlation between the experimental data and predicted values. The results of the proposed model can be used to give a good prediction of the spinning process during membrane fabrication.

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The conductivities of the obtained PAni/Fe3O4 composite nanotubes prepared by ultrasonic dispersion method were measured by the standard Van Der Pauw DC four-probe method. Conductivities of the composites were measured as a function of wt% Fe3O4 nanoparticles. It was found that the conductivities of the PAni nanotubes containing different wt% Fe3O4 nanoparticles are lower than that of bulk PAni and decreases with the increase of wt% Fe3O4 nanoparticles. The conductivities also increase as the doping level in the composite increases. The FTIR Spectra indicate the presence of PAni containing Fe3O4, FESEM results prove that nanostructure of PAni/Fe3O4 is produced by this method. The lower conductivities of PAni/Fe3O4 composite may be due to the lower concentration of dopant used in the polymerization process and the optimization of this composite allows this material being use as a matrix for development of electrochemical sensors.

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Currently available conventional methods for the synthesis of silicon carbide nanotubes are highly demanding in terms of the energy consumption, temperature and reaction duration. Synthesis of silicon carbide nanotube through microwave irradiation is thought to be more efficient considering shorter time and lower energy consumption is needed. In this paper, for the first time the synthesis of silicon carbide nanotubes was reported through microwave heating of mixture of carbon nanotubes and silicon dioxide in argon atmosphere at temperature of 1400°C. Silicon dioxide and carbon nanotube in the ratio of 1:3 as suggested by previous study were mixed in ultrasonic bath for 2 hour using ethanol as medium. The mixture was dried on hot plate and cold pressed into a 3mm pellet. The pressed pellet was then placed in an alumina crucible filled with silica sand acted as heat insulator and SiC susceptor. The pellet was heated to 1400°C at heating rate of 30°C/min and hold at 1400°C for 40 minute. X-ray diffraction analysis verified that silicon carbide nanotubes were produced after the mixture was subjected to the microwave irradiation. Scanning electron microscopy analysis revealed the tubular structure of carbon nanotubes was retained after the microwave irradiation by formation of silicon carbide nanotubes which have tubular structure. Fourier transform infrared (FTIR) spectroscopy show that Si=C bond has the absorption bands around 900cm-1 to 700cm-1 and band gap of silicon carbide nanotube was found out to be 2.76 eV.

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In this paper, we focus on extended numerical methods for solving fuzzy nonlinear equations. An extension of false position method into fuzzy setting is proposed for solving such equations and it will be referred to as fuzzy false position method. An algorithm for this process of solving will be provided. For the purpose of optimization, genetic algorithm will also be incorporated in order to find the best solution for the problem under consideration. Two numerical examples with graphical representations are provided to illustrate the efficiency of the proposed method. The results showed that the proposed method is able to find the best solution for fuzzy nonlinear equations.

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The aim of this paper is to propose an alternative method to approximate the solution of fuzzy nonlinear equations. The proposed method will be referred to as Fuzzy Homotopy Continuation Method (FHCM). In FHCM, a fuzzy nonlinear equation is embedded in one of the parameter family of the problems i.e. where is considered as an approximate value to the original problem and is corresponding to a problem with a known solution. A continuation method is then attempted in order to determine the sequence of problems corresponding to A numerical example on obtaining the solution of fuzzy nonlinear equation will be demonstrated to illustrate the capability of FHCM.

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The methanol extract of the heartwood of Artocarpus heterophyllus were purified using several chromatography tehnique to give eleven flavonoid compunds : gemichalcone A (1), gemichalcone B (2), norartocarpanone (3), artocarpanone (4), dihydromorin (5), norartocarpetin (6), artocarpesin (7),cycloartocarpesin (8), cudraflavone C (9), artocarpin (10), and cycloartocarpin (11). The structure of these compounds established by spectroscopic mean and by comparison with the literature values. Compound 10, exhibited very strong (IC50 < 2,0 ?g/mL), whereas compounds 2 and 9 showed strong inhibition (IC50 2,1–4,0 ?g/mL) against P-388 cell lines.

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In this study, the mechanical properties, morphological studies and thermal properties of the PLA/PKS composites were investigated. The palm kernel shell (PKS) filled polylactic acid (PLA) composites were prepared at different PKS loading by using melt mixing compounding at 180 ºC. The 3-aminopropyltriethoxysilane (3-APE) was selected as coupling agent. The incorporation of PKS into PLA had decreased the tensile strength and elongation at break of the PLA/PKS composites. However, the composites’ modulus of elasticity was increased with increase of PKS loading. The PLA/PKS composites treated with 3-APE had higher tensile strength and elongation at break but lower modulus of elasticity. This improvement was attributed to the enhanced PKS-PLA interaction. The better interaction of PKS and PLA was proven through scanning electron microscopy and Fourier transform infrared analysis. The thermal stability of PLA/PKS composites was enhanced with 3-APE treatment.

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The use of polymeric material has increased progressively in recent years with small percentage of plastics are currently recycled for further use. In this present study, carbon from polymeric material such as recycled Polypropylene (PP) is utilized as a reducing agent which has not been extensively investigated especially in steelmaking processes. The reduction reaction through composite pellet approach was conducted in a horizontal tube furnace at low temperatures of 900 °C, 950 °C and 1000 °C. The reduced sample was examined with Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD) to understand the reduction mechanism of composite pellets. XRD pattern confirmed that hematite was the main phase present in the sample while the phase’s transformation was occurred from iron oxide to metallic iron in tandem of temperatures were rising up. The influence of high temperatures revealed a clear structural evolutions of the samples confirms that the occurrence of three successive of reduction steps, through magnetite and wustite to metallic iron. This scientific study of using PP as a reductant will create new opportunities to transform waste plastics as carbon materials in steelmaking processes.

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Agricultural waste can be an interesting possibility to be applied as reducing agent instead of coal-based used in steelmaking which is considered to be one of the largest energy intensive sector. As a result of enormous amount of wastes generated by agricultural sectors, numerous research on application of waste as energy source have been conducted. Utilization of these wastes as valuable materials could provides solution to environmental problems. This present study investigated the reduction of iron oxide with agricultural waste from palm shells in a horizontal tube furnace. Composite pellets of iron oxide (96.0 % Fe2O3) with palm char in three different proportions were rapidly heated up to 1550 °C under argon gas flow. The reduced sample after reaction time, 30 minutes was examined using a Scanning Electron Microscope (SEM) equipped with Energy Dispersive Spectroscopy (EDS) and measured for degree of reduction. The results indicated that iron oxide which composed primarily Fe2O3 can be effectively reduced by palm shells as reductant where a significant improvement in the degree of reduction. The initial hematite powder could successfully reduced to metallic iron after a complete reduction process. This finding indicates that carbon from palm shells could be used as reductant in steelmaking processes.

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Renewable energy for steelmaking production was explored widely by researcher to replace the utilization of coke towards more sustainable steelmaking. By converting agricultural waste (palm shells) into renewable carbonaceous materials in EAF steelmaking has potential to contribute energy conservation and emission reduction. The present study investigates the reduction behavior of the FeO rich slag by agricultural waste and metallurgical coke for the production of metallic iron through experiments conducted using high temperature horizontal tube furnace. Activated carbon from palm shell was prepared by physical (PAPC) and chemical (CAPC) methods. PAPC was prepared by devolatilized in N2 atmosphere at 450°C while CAPC were soaked in H3PO4 for one hour before devolatilized. All carbonaceous materials including coke were prepared in powder form mixed with an EAF slag. The composite fine powder was inserted into tube furnace at 1550°C under Argon gas with a flow rate 0.01L/min for reduction reaction with extended time was twenty minutes. The renewable carbon source from PAPC and CAPC showed more efficient due to improvement in degree of FeO reduction compared to conventional materials. The difference of activation methods used revealed an excellent degree of reduction and metallic iron was produced. A study using palm shell wastes as new reductant in steelmaking industry may open the opportunities to transform the waste into valuable carbon materials.

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Nowadays, there is an increase in research about renewable natural fiber as an alternative solutions in replacing synthetic fibers such as glass fiber as reinforced composites materials that are non – biodegradable and non – ecofriendly to the system. Natural fibers are also known for its low cost production yet have excellent mechanical properties and is environmental friendly. One of the natural fiber resource is pineapple leaf fiber (PLF) which is planted widely in Malaysia. From current research, PLF contains high cellulose and exhibits good mechanical properties especially from Josapine family. In this study, the PLF from Josapine is used as reinforced materials and starch (SH) is used as the binder. Additionally, the effects of PLF loading and PLF fiber length on the mechanical properties of PLF/SH composites is also analyzed. Compositions ratio of PLF/SH composites is fixed at 50/50, 60/40 and 70/30. The lengths of the fiber are fixed to 2 cm, 4 cm and 6 cm. Before the fabrication, PLF has underwent alkaline treatment to increase the strength of fiber. All nine samples has underwent four different tests to determine the mechanical properties which are tensile test, hardness, density and microstructure analysis. PLF loading of 70% with 6 cm in length shows the higher values of tensile stress, density and hardness which are 14.53 MPa, 33.63 and 1.20 g/cm3 respectively.

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Reconfiguration is one of the demands in most of manufacturing industries in order to support unpredictable global business market and to fulfill the various types of customer needs. A virtual commissioning is used as a tool to verify the control system in a simulation environment before the real system is developed. One of the techniques in virtual commissioning is Software-in-the-Loop (SIL). The benefits of SIL technique is it can estimate the real state of control system during the simulation stage. This paper presents the understanding of the SIL technique by using an implementation of the simulation based control system to support the reconfiguration of a manufacturing system. The result of the demonstration shows that the SIL technique has a potential to be used as a tool to configure the reconfiguration of the manufacturing system even tough the reaction time is slightly longer compared to the system simulation.

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In order to provide thermal protection for the external surface of the gas turbine blades, film cooling technique has been applied. With the aim to reduce the lift-off effect cause by the counter rotating vortex pair (CRVP) formed in the cylindrical cooling hole configuration, coupling film cooling designs have been introduced. Double Cylindrical Hole (DCH) which is one of the coupling holes is the main subject for the present study with the implementation of two geometrical parameters; length between the holes in x-direction, LoD and upstream ramp. Five double cylindrical hole arrangements have been developed with these two parameters and DCH 2D35 is considered as the baseline which will be discuss more later on. Meanwhile for the flow parameter, the main parameter considered is blowing ratio, M. ANSYS CFX ver. 15 has been used in the present work and all the analyses have been carried out using Reynolds Average Navier Stokes analysis with the implementation of k-? turbulence model. In general, the results show that the increase in LoD hindering the film cooling effectiveness at the distinct hole region, but decays slower in the downstream compared to the baseline design. Meanwhile, the results of upstream ramp variations demonstrate that the upstream ramp shows significant improvement of film cooling effectiveness at near exit hole region, but as the film cooling moves further downstream, it decays rapidly in comparison with the baseline. As for the blowing ratio effect, the film cooling have been observe to decay as the blowing ratio increases similar to the general ideas of conventional cooling hole.

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Due to high turbine inlet temperatures in modern gas turbines, film cooling technique was used to provide thermal protection for turbine components from being damaged by hot combustion gases. Combining two round-hole of film cooling is a better way to enhance the film cooling effectiveness. In the present work, a group of simulations consists of 27 cases using combined-hole unit with opposite compound-angle were carried out. The objective of this work is to find a good arrangement of combined-hole film cooling which produce better film cooling effectiveness. Effect of different blowing ratio, M with combination of different distance between two holes in mainstream direction, LoD, and compound-angle, ?1 / ?2 of film cooling hole were considered. As observed, lateral coverage was spread wider as the compound-angle and blowing ratio increase. While increasing LoD produces an insignificant results. However, increasing blowing ratio also resulting drastic decrease of film cooling effectiveness at further downstream. In the present study, area average film cooling effectiveness were determined to evaluate the general film cooling effect of different arrangements. Based on the area coverage, M = 1.5 shows an uncertain results for all arrangements. An early separation, spread and lift-off cause the different results at higher blowing ratio. The combination of the lateral distance of the two holes with their compound-angles for the highest film cooling effectiveness is different at different blowing ratios.

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Titanium (Ti) is widely used in dental and orthopedic implants because of its good biocombatibility and high corrosion resistance. Titanium oxide (TiO2) has shown to exhibit strong physicochemical bonding between Ti implant and living bone because of its ability to induce bone-like apatite in a body environment. Ti is always coated by an oxide surface layer of 1.5-10 nm thickness. TiO2 crystalline structures; anatase and rutile present several distinctive features, such as photo catalytic behavior, superhydrophilicity and biocompatible properties. Anodic oxidation is used to modify the surface of commercially pure titanium (Cp-Ti) in a mixed acids electrolyte in order to maximize and characterize the TiO2(anatase) crystalline phase.In the present work, thick films of the anatase polymorph of TiO2 were formed on Ti-Cp foil under potentials 150V-190V at current densities 40 and 60 mA/cm2 for 10 min. Multiple characterization techniques were used. Glancing angleX-ray diffraction (GAXRD) is used to obtain crystalline phases, field emission scanning electron microscope (FESEM) is used to obtain surface images and water contact angle (WCA) is used to obtain the wet ability of the oxide surface. According to GAXRD results the intensity of the major peak increased with increasing applied voltage and current density. Molar concentration of H3PO4 has an inverse impact on the crystallinity, thus the peak intensity. Anatase peaks decreased at all voltages when H3PO4 concentration increased. An increase in H2SO4 molarityresults in higher crystallinity. A predominance of anatase is noticed at all cases. This means that the amount and/or crystallinity of anatase are/is influenced with these parameters. FESEM images observed porous structure in which pore size increases with applied voltage (150-190 V) at current density of 60 mA/cm2. Surface morphology dependents on the electrolyte composition. Surface morphology have porous surface which resulted from local film breakdown. WCA results of the coated samples have shown to be more hydrophobic at higher voltages while observed to be more hydrophilic at higher molarity. The increase of anatase crystalline with increasing molarity could be related to the more wet ability, an exception for the less wet ability for sample surfaces produced at 2 M H2SO4/0.1 M H3PO4at 60 mA/cm2could be due to the rutile presence according to GAXRD results.

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Short Piled Raft foundation system is introduced and intended to solve foundation problem on peat, neither using removal and replacement method nor soil stabilization. In order to obtain a better performance for reducing settlement, two cases concerning the use of type of pile were investigated, concrete pile and closed end steel pipe as pile respectively. Finite element method to simulate the stability performance was used. Concrete slab of 3 m x 3 m square as a raft was assumed to be built on peat and the material properties of pile and raft were constant. Point load from 10 kN to 100 kN with increment of 10 kN were also considered as a static load, acted at the centre of the concrete slab. The outer diameter of pile was 0.30 m; the length of pile was 3.00 m and the pile spacing was 1.00 m. The raft thickness was considered to be constant of 0.15 m. The result showed that the use of closed end steel pipe as pile produced better performance significantly than the use of concrete pile. At the maximum load of 100 kN, the maximum total settlement of the concrete pile used was 62.74 x 10-3m which was higher than the maximum total settlement of closed end steel pipe used was 45.73 x 10-3m.

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This paper presents the novel application of foamed concrete as infill for reinforced concrete beam. The combination of foamed concrete infill and normal concrete beam produces composite-based-concrete-structure that has an advantage due to the lighter weight. This system of the beam become an ideal situation to reduce the weight and as material saving without having to compromise on its strength and serviceability. In this study, the beam specimens were designed with a dimension of 1100 mm length, 200mm depth and 150mm width. The foamed concrete infill has a size of 1000mm length, 125mm depth and 25mm width. The depth of foamed concrete infill is setup at 100mm, 125mm and 140mm. All beam specimens were tested under four-point bending test to obtain the load-deflection profile and failure modes. Meanwhile, cube samples were also prepared for both normal concrete and foamed concrete. The compressive strength of normal concrete and foamed concrete achieved the target of 21.3MPa and 8.3MPa respectively. The ultimate load of reinforced normal concrete beam, reinforced concrete beam with foamed concrete infill and reinforced foamed concrete beam are 62.07kN, 53.11kN and 27.84kN, while the deflections are 9.6mm, 2.1mm and 1.9mm. Although the strength of reinforced concrete beam with foamed concrete infill is lower than reinforced normal concrete beam, but it poses high serviceability.

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Soil erosion occurs through the process of wearing away of the earth’s land surface through rain, wind or other agents. Dust storms cause air pollution as the dust particles are carried by the wind. Dust emissions from unpaved ground can cause enormous problems such as dust storms that may lead to accidents and also respiratory tract diseases. The main objective of this study was to investigate fugitive dust resulting from unpaved ground caused by wind. Two types of clay soil (type A and B) was obtained from two different locations in Johor, Malaysia. Dust emission assessment equipment consisting of a purpose built wind tunnel was developed and modified to determine the assessment of the soil erosion index for simulated natural ground surfaces and was used also in laboratory testing. The assessment was carried out to preset values of the wind speed which were 2.9 m/s, 3.8 m/s and 7.2 m/s in environmental temperatures of 26 ? C, 40 ? C and 60 ? C in the various tests. The test soil specimens were prepared in a mould with dimensions of 60 (L) x 60 (W) x variable height (maximum 5mm). A total of 90 tests were carried out on 2 different samples (type A and type B). The binding properties of fines and stabilisers within the gravel particles of a road surface may be reduced in the dry season due to moisture loss. The foremost industry need is to develop new and appropriate instrumentation for the evaluation of a reliable soil erosion index.

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In response to the issues faced by the Malaysian construction industry, the Construction Industry Development Board (CIDB) has identified and recommended partnering as a method to overcome the current problems within the industry. This is also in line with the establishment of “Public Private Partnership Unit” (3PU) under the Prime Minister’s Department in 2009 to oversee the implementation of partnering in the Malaysian construction industry. It is crucial that the policies in place should facilitate the practitioners so that the full potential of partnering to overcome the many problems in the Malaysian construction industry can be fully utilized. This paper describes the conceptual aspects and the preliminary stage of an ongoing research. The research aims to identify whether current policies in place are serving as an enabler for effective partnering or a deterrent to the adoption of partnering by the practitioners in the Malaysian construction industry. It is determined that apart from issues identified from literature review, the preliminary qualitative study has revealed that enabling factors such as political and legal system influence towards partnering should be considered in formulating effective policies for successful partnering in the Malaysian construction industry.

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Generated construction waste is influenced by various aspects which are necessary to be identified for better understanding of their impact towards sustainability. Hence, this paper aims to test the hypothesis between construction waste and the sustainability elements by developing a structural model of the waste generation. The data are gathered using questionnaire technique which consists of 13 effects factors under 3 main groups (Environment, Economic and Social). In 7 months, a total of 500 questionnaires are distributed and 302 questionnaires are returned with a response rate of 60%. From these returned questionnaires, only 277 questionnaires are valid and reliable responses which are received from contractors, consultants and clients. A structural model is developed based on the 3 groups of effect factors via Partial Least Squared-Structural Equation Modeling (PLS-SEM) approach. The hypothesis testing is carried out using the bootstrapping procedure by generating 5000 random samples. From this testing, it's found that the 3 groups are significant with a t-value = 2.58 (99% confidence level). Therefore, it indicates that the generated construction waste are directly affected by the environment, economy and social aspects. The study suggested to all construction personnel and related authority for taking part actively in minimizing the construction waste generation in order to achieve green nation status.

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Ultrasonic Pulse Velocity (UPV) is one of the Non-Destructive Testing (NDT) methods of assessments concrete properties. This tool is known as an excellent method for determining the quality and uniformity of concrete and its ability to determine the defects on concrete structures. This study was conducted to evaluate the effect of concrete with difference aggregate sizes and curing time by measuring ultrasonic wave velocity and UPV is one of the techniques in the evaluation for determining the damage mechanism in the concrete structure. Therefore, 9 specimens with size 150mm x 150mm x 150 mm cubes were cast for ultrasonic evaluation with different aggregate sizes of 10 mm, 20 mm and 30 mm respectively. Ultrasonic measurements were recorded at 7, 14 and 28 days after concrete has been casting. The results revealed that UPV decreases with the increase aggregate size. It was also found that UPV increases as the concrete curing time increases. Additionally, the compressive strength of concrete was affected by difference aggregate sizes where the strength of concrete increases as the aggregate size decreases.

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Groundwater modeling, even as approximations, is a useful investigation tool that groundwater hydrologists may use for a number of applications. The application of modeling is widely used as powerful tool for management or mitigation works. Through modeling, the characterizing the hydrogeological conditions, understanding and simulating groundwater flow patterns as well as groundwater flow directions, assessing groundwater balance, and understanding the hydraulic interaction between river and groundwater can be done. Thus, this study was conducted with the aim to understand the hydrologelogical features and to generate the groundwater flow pattern. The hydrological data such as rainfall, temperature, groundwater level and river flow. While for the geological features, the soil types was determined and derived based on the existing borehole data. Based on the hydrological analyses, the annual rainfall data, evaporation, evapotranspiration and runoff in study area is approximately 2,217 mm, 149.53 mm/a, 320 mm/year and 200mm respectively. The groundwater system that was simulated are confined aquifer where, clay, silt, silty clay and clayed silt are found at 40m depth for downstream area, while, for upstream are consists of gravelly silt, clayed gravel, silty sand, sandy silt and clayed silt area also found in 40 m depth. Through the modeling, the understanding of groundwater flow pattern in area was understand. The groundwater flow is flowing from upstream to downstream area. Lastly, to verify the model results, the model result was compared with the measured data. By referring to root mean square error (RMSE) the error is less than 5% which is 4.98%. The model result from this study was expected to become a helpful tool to assess the impact of changes of the groundwater regime in the environment, to set up/optimize the network monitoring for future sustainable groundwater usage.

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Cold-formed steel is the well-liked structural materials in the construction industry and used as an alternative construction material upon the traditional material such as reinforced concrete, hot-rolled steel or timber. The purpose of compacted soil is filled into a cold formed steel section to contribute to the environmentally friendly with reasonable strength and can also reduce production costs without concrete beams. The cold-formed steel material is selected and combined with the compacted soil to construct the beam that could increase the ultimate moment. Compacted soil from the Kaolinite group is prepared and tested to find out its properties. Two cold-formed steel channels are connected face to face to form a built-up box section, tightened with bolts and nuts. Three different bolt spacing arrangements are prepared. The main purpose of the study is to determine the ultimate load of the beam with and without compacted soil, as well as to investigate the relationship of the bolt spacing arrangement to ultimate load resistance. From the result, built-up CFS beam with compacted soil (CFSBCS) showed higher values of the ultimate moment compared to built-up CFS beam without compacted soil (CFSB). Bolt arrangement in the middle spacing influenced the overall ultimate load resistance of the beam. The ultimate load resistance reduced when the length subtraction between bolt arrangement, B and C is less. It is concluded that CFSBCS is able to achieve reasonable ultimate moment and also able to increase initial stiffness.

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Wastewater that been discharge from meat processing industry has high content of nutrients such as nitrogen and orthophosphate. These nutrients was found abundant in meat products which is essentials for algae growth specifically. However, if these wastewater being discharge to environment without any treatments to assimilate those nutrients, it can lead to eutropication which also known as algae bloom; resulting the destruction of the ecosystem and health to human. Hence, this paper will illustrate the superiority of using microalgae botryococcus sp. in assimilate nutrients from meat processing wastewater i.e. Total Nitrogen and Orthophosphates. Furthermore, through this study, the primary characteristics of wastewater to be established prior and after treatments for assimilation analysis. From this, the efficiency of microalgae in phycoremediation process can be ascertain and recognized. Three different concentrations of botrycoccus sp. were use i.e. 1x103 cells/ml, 1x104 cells/ml and 1x106 cells/ml. The microalgae then were cultivated into wastewater of 9.00 am and 12.00 pm. sampling in triplicate manner for phycoremediation took place. The results show that highest removal of Total Nitrogen and Orthophosphate is at concentration of 1x106cells/ml i.e. 97% and 94% at 12.00 pm. sampling. Same goes for Biological Oxygen Demand, BOD and Chemical Oxygen Demand, COD removal, maximum removal are also at concentration of 1x106 cells/ml i.e. 97% and 94% at 9.00 am. sampling.

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This paper contribute towards factors of delay as a whole in Malaysian construction sector by application of Industralized Building System (IBS). Similarly to other developed countries, Malaysia getting benefits through returns from construction industry, as identified through Gross Domestic Product (GDP). However, there are still some issues in the IBS construction industry to overcome until the time and cost performance plunged to reduce. The focus of this study is to inquire factors in delay issue which involves series of people which act as project stakeholders particularly in Malaysian Industrialized Building System. A number of factors causing delay to construction project in IBS are found by previous study. The prominent factors of delay in IBS are poor expertise to engange with unpleasant situation during handling IBS project, lack of communication between stakeholders, ineffective team alliance, poor client behavior, poor financial management and external factor. Study regarding delay issue with IBS adoption in foreign countries such as United States and China was progressively conducted. In Malaysia, a survey towards establishment and development of IBS has been conducted. It can be concluded that IBS project faces numerous challenges to be implement resulting in the delay. However, very few studies have been attempted on the factors causing time delay. Therefore, this paper will focus on factor which contribute into delay in Malaysian IBS project.

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Warm mix asphalt (WMA) technologies that use foaming most commonly used due to their cost effectiveness. This technologies allow the reducing of asphalt binder temperature by adding additives foaming chemical. Civil engineering infrastructure materials can significantly contribute to the sustainability movement through the use of recycled materials and more environmentally friendly production processes. Recycling has been defined as a method by which reclaimed asphalt pavement (RAP) is combined with new aggregate and bitumen or recycling agent to produce hot mix asphalt and obtained by pavement milling with rotary drum cold milling machine or from a ripping/crushing operation. This paper described the feasibility of utilizing Reclaimed Asphalt Pavement (RAP) in Warm Mix Asphalt using foaming technology. Despite the promising performance in comparison with HMA, this technology has not yet gained acceptance in asphalt industry. In order to reach widespread implementation it is necessary to prove that WMA has the same or better characteristics and long term performance as HMA. Besides, it discover whether by the use of foamed warm asphlat additives are possible to reduce the high temperature whilst slower aging of the modified binders and will helps to give better understanding on environmental effect of both human and materials.

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Malaysian government has introduced several policies in helping the indigenous people known as Bumiputra. Amongst the actions is by awarding certain government contracts to Bumiputra contractors only. Unfortunately, many of the contractors are not able to survive in this contractual business due to many factors that has commonly been highlighted in local newspaper. Thus, this paper presents a preliminary investigation on Bumiputra’s contractors failure factors in southern parts of Malaysia peninsular. At the initial stage of this study, an interviewed was carried with the Secretary of Malaysian Malay Contractors Association in Johor on the issues faced by Bumiputra contractors. He pointed 10 issues that usually engulfed Bumiputra contractors during handling the awarded projects. Then, a survey was carried with 15 selected Bumiputra contractors who are well experienced in handling construction projects to gauge their views on the relevancy of 19 identified factors which are clustered into 6 groups. The collected data was analyzed by using mean score to rank these factors according its degree of relevancy to Bumiputra contractors issues. This study found 5 most relevant factors that are two factors from financial group, two factors from risk group and one factors from other resources. These factors are F2-insufficient cash flow/capital to carry out a construction project, F3-difficulty in securing bank loan due to inability to get guarantor/collateral fixed, R1-unable to anticipate the difficulty of getting material and worker, R3-unable to anticipate risks from material price escalation and OR2-lack of construction skilled workers (foreman, carpenters, bricklayer, etc). These findings are very helpful for the Bumiputra contractors in preparing an effective construction project management strategy for their future project.

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Public Private Partnership (PPP) requires a project principal, which primarily is the government and private sector companies to work through a sharing of risks and benefits from a procured public sector project on a long-term collaborative basis. A similar type of procurement approach has been introduced in the United Kingdom (UK) in the early 1990’s known as the Private Finance Initiative (PFI). This is a form of PPP that combines a public procurement programme, where the public sector purchases capital items from the private sector, which then arranges project funding via private financing. The PFI/PPP approach has been introduced in Malaysia through the government’s Ninth Malaysia Plan (9MP) in 2006 and since then a number of mega construction projects were sanctioned for provision. About a decade our construction industry and government authority disclosed to the PFI/PPP scheme and what is lesson learn they get from this type of procurement. This paper presents the methodologies used to determine the level of knowledge and awareness of PFI/PPP procurement process among government servant that involve in the PFI/PPP programmes. Due to finding of the research most of government servants that involve in the PFI/PPP procurement have a good and average knowledge about the process of PFI/PPP procurement that implement in Malaysia. The poor level of knowledge happens because of minimal experience involve in the PFI/PPP project, lack of references and inadequate of guideline PFI/PPP procurement scheme.

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Nature is full of flow control examples and has long provided subjects of interest in the field of fluid mechanics. From birds flying in a V-formation, to feathers on a bird, to scales on a butterfly wing, to the skin of marine creatures, such as octopus, fish, dolphins, and sharks that provide abundant shape resources for restructuring the surfaces to enhance flow of underwater vehicles. Riblets like shark skin have gained renewed interest in academic fields of study and in industry due to several advantages in manipulating the turbulence boundary layer. Drag measurements have been carried out in a water channel over flat plate. In these experiments, smooth plate was compared to riblet-structured films. This was done for different dimension of V-groove riblets fixed on the surface with the riblet direction aligned with the flow. The lateral spacing between the triangular shaped riblets varied between 8005m and 20005m. The drag reduction experiments show that the maximum drag reduction rate of up to 11% over the velocities tested.

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Million tons of plastics wastes are discarded into landfill each year and may remain in there up to 1,000 years before being decompose. With this, it is potential pollutant in the soil and water. Relatively small amount of plastics are recycled due their different chemical compositions and with the presence of other materials such as ink, paper and non-plastics. To separate and sort the plastics from non plastic material is difficult and laborious. Catalytic pyrolysis of plastics waste is one one of the processes to overcome this problem and able to generate alternative energy. This technology can reduce global warning and assist waste decomposition. The thermal and catalytic pyrolysis reaction of plastic resulted in producing fuel gas and liquid fuel. The objective of this work is to study the effect of nickel catalyst support either with alumina or oil palm biomass ash for liquid fuel production. Base on the Malaysian municipal industrial waste, a synthetic plastic mixture was used as a feed source for the catalytic pyrolysis. The composition of synthetic plastic mixture consists of (in weight percentage basis) 35% high density polyethylene (HDPE), 35% low density polyethylene (LDPE), 19% polypropylene (PP) and 11% polystyrene (PS). Nickel with 20% (wt) and consists of cerium with 10% (wt) supported either by alumina or palm oil biomass ash was used as a catalyst with 1:3 (catalyst to plastic weight ratio). The conditions used to pyrolyze the raw materials were with 25 ml/min nitrogen stream at 500 0C for 60 minutes. The products produced i.e. liquid oil, uncondensed gas, and spent catalyst were analyzed and characterized via BET, TGA, SEM, GC-MS, GC-TCD, and FTIR. The hydrocarbon fractions obtained from the catalytic pyrolysis using alumina and oil palm biomass ash as supported catalyst did not have much difference, where they gave the same area percentage of light (petrol), middle (petrol), and heavy (diesel). The FTIR spectra also showed the same profile for diesel and liquid fuel produced from both supported catalytic pyrolysis. Oxide compound were presence in both of nickel alumina and oil palm biomass ash, promoted cracking and aromatization reaction. However, nickel oil palm biomass ash which is filamentos carbon was a better catalyst than nickel alumina due to resistance coking affect that lead to higher catalytic activity and produces higher plastic conversion into valuable energy resource.

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One of the most important elements of liquids transportation process, mainly the crudes and oil products, is the pipelines flow assurance by maintaining lowest pressure losses. Existence of two phase flow in the pipe would generate different pressure drop than the designed drop under single phase flow assumption. This paper presents CFD simulation results of solid-in-liquid, i.e. slurry horizontal pipe flow using ANSYS-CFX software. The influencing of sand particles diameter and concentration on the pressure loss of pipelines at various flow rates of sand-in-Diesel 2D was studied. Three cases have been investigated; single liquid flow, homogeneous slurry sand-in-liquid flow, and two layers slurry flow, suspended layer in the upper and dead bed in the bottom. For validation, water flow was also simulated. Water and Diesel 2D were assumed Newtonian, incompressible and the region of simulation was fully developed. Mesh independency study was conducted so that the produced results would not be affected by the number of element. Fluid flow was simulated as single phase flow with velocities of 0.5, 1.0, 1.5 and 2.0 m/s. Then, particles were dispersed in the flow with volumetric concentrations of 10%, 15% and 20%. The investigated particles sizes were 0.25, 0.50 and 1.00 mm. The simulation procedure was validated through comparison of the pressure drop and friction factor results with the well-established methods in the literature. Analysis of the homogeneous solid-in-liquid flow results demonstrates an increase in the pressure drop. In the case of two-phase two-layer flow, the pressure drop increases dramatically due to the high shear between the upper and lower layers leading to very high resistance at the interface surface between the stationary bed and the upper homogenous layer. The simulation explores interesting phenomena of particle settling due to the high shear at the interface surface resulting in creation of moving bed between the layers. Further investigations will enhance the understanding of the multi layers slurry flow phenomena.

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Calcium oxide (CaO) is usually produced via thermal decomposition of limestone's obtained through mining and quarrying. However, this study manages to exploit the vast availability of natural calcium sources (Anadara granosa) or locally known as cockle shell in Malaysia. The efficiency of the calcinations process that transforms calcium carbonate (CaCO3) to calcium oxide (CaO) was often depended on the variable involved. Therefore, we wish to demonstrate the effects of experimental variables (calcinations temperature, heating rates and particle sizes) on calcinations of CaCO3 via thermos-gravimetric analyzer (TGA). Analysis of XRF, XRD and SEM were also conducted on the CaO produced after calcinations.

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This paper aims to investigate the effects of aspect ratio (AR) and geometry have on the flow dynamics of a free end finite cylinder via numerical simulation. The AR used in this investigation is AR=3, 5, 7 whilst a circular cantilever cylinder and a rectangular flat plate are used as the geometry. The Reynolds number based on cylinder diameter is 20000. k-? (SST) is used to model the turbulence. End tip effects are seen on free end finite cylinder. By studying the velocity defect flux (Q), tip effects are found to be independent of AR. They are however limited to 2D~3D for circular cantilever cylinder and 3D~4D for rectangular flat plate. Velocity defect is stronger for rectangular flat plate than that of circular cantilever (the range differs from 6.81% to 206.41%) suggesting a stronger vortical activities are present in the wake of rectangular flat plate. It is supported by turbulent kinetic energy (TKE) contours whereby the maximum TKE is approximately 20%~50% higher in rectangular flat plate at each respective AR.

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Eggshell was waste from industrial and household that was found in much amount and really easy to found. Eggshell was contained CaCO3 about 90 %w/w. CaO was main component of gypsum that could obtained from CaCO3 processing, hence eggshell could be used as an alternative raw material for gypsum manufacture. CaCO3 from eggshell could be used for gypsum manufacture by calcinations process in the furnace at temperature 900 0C in order to deform CaCO3 in the eggshell into CaO, then calcined material was mixed with aquadest and sulfuric acid solution and was stirred until precipitate was formed. Then, the precipitate must be filtered and dried in an oven until dried. The result was shown that increase the mixing concentration gave effect the increase of gypsum strenght. The maximum result was shown in variation ratio of 35% calcined material, 50% aquadest and 15% sulfuric acid, with elapse time was 5.5 minute, load was 6.5430 lbs at compressive strenght test. The composition of maximum result was shown 0.48% of SO3, 7.68% of CaO and 0.98% of H2O at XRD and SEM test.

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Industrial production of copper solutions, in addition to the basic components (Cu, Ni), contain undesirable impurities which include arsenic and antimony. The work is devoted to studying the process of withdrawal of antimony from copper electrolyte with calcium carbonate, which is present in nature as a known mineral and in many cases is waste. Studies of the precipitation of antimony with calcium carbonate from copper-containing sulfuric acid solution was carried out by probabilistic and deterministic planning of the experiment. For the identification of solid precipitation X-ray analysis was used. The studies determined the optimum conditions fot precipitation of antimony from copper-containing highly acidic solution in which antimony precipitates the most: Ca:Sb ration - 2:1, the temperature to 25 °C, the content of sulfuric acid in the copper electrolyte – 100 g/l, the duration of process from 45 minutes to 60 minutes. The use of calcium carbonate to clean technology solutions allows you to bring the content of antimony to the optimum content.

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Potassium methoxide is the catalyst for methanol carbonylation process with the CO. This catalyst is prepared by reacting potassium hydroxide with methanol at a temperature of 25-50 oC. Besides the reaction temperature, preparation of catalyst was influenced by the composition of the feed of reactants. Chemical composition in the liquid phase were analyzed using gas chromatography method, and composition of vapour phase was predicted using UNIFAC model. Concentration of CH3OK in the catalyst solution increases with increasing molar ratio of feed and temperature. Yield of CH3OK decrease if molar ratio of feed increased. The highest concentration of CH3OK achieved at molar ratio of feed 0.039 and temperature 50oC. Reaction rate for alcoholysis of potassium hydroxide is a function of the concentration of potassium hydroxide. The activation energy was found 17.81 kJ/mole, and pre-exponential factor was 26.3 min-1.

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Kinetic study of free fatty acids (FFAs) esterification for biodiesel production from palm fatty acid distillate (PFAD) using sulfated zirconia (S-ZrO2) prepared by solvent-free method calcined at low temperature as the heterogeneous catalyst was studied. The reaction was performed in a batch-stirred reactor at the different temperature to obtain the kinetic data. The effect of reaction condition such as methanol to PFAD molar ratio, stirring rate and catalyst concentration on FFA conversion were also investigated. The experimental data was interpreted with the second-order heterogeneous kinetic model involving the rate of mass transfer and the rate of reaction. The proposed kinetic model and the experimental data are in good agreement.

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Modification adsorbent of magnetite (Fe3O4) coated humic acids (HA) by a co-precipitation method using ammonium hydroxide have been successfully synthesized. The characterization of FT-IR spectra indicate that the coating Fe3O4/HA have been bound by Fe-COO-R and the XRD patterns does not affect of the crystals structure. It's applications to degrade of heavy metal Cu and Cr from liquid waste on plywood industries. Degradation of Cu on Fe3O4/HA and Fe3O4 i.e up 70-90% and then for Cr on Fe3O4/HA and Fe3O4 i.e 10-40% only. The performance adsorbent of Fe3O4/HA more effectively than Fe3O4 for degradation of heavy metal Cu and Cr.

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Currently, the enzymatic production of biodiesel has drawn considerable attention. But, it still cannot apply to commercial industry because the cost of enzyme providing is high due to the decreasing of enzyme activity and stability in reaction. So, it cannot be reused. The advantage of enzymatic process is high-purity products because it is easy in removing by-products such as glycerol. But, there is possibility that enzyme activity and stability decrease because of inactivation by acyl acceptors and impurities in oils or by-products, glycerol. Choline-based ionic liquids used as a solvent supposed to decrease inactivation because it is greener than organic solvents and non-volatile. This study used palm oil, ethanol used as an acyl acceptor because it is more renewable than methanol, Novozym® 435, and ChCl as a solvent. The reaction parameters that used in this research were the temperature reaction, reaction time, and ChCl dosage. This study showed that yield biodiesel in ChCl system was lower compared to ChCl-free system for a single use. But, it could obtain the highest yield when enzyme was reused for several times. The highest yield of 99.50 % was obtained in third reuse of enzyme at molar ratio of 1:6, temperature of 40ºC, reaction time of 7 hours and 0.5 % of ChCl. The decreasing of yield biodiesel occurred when ChCl concentration was increased. This result also showed that time reaction gave an effect to ethyl ester yield between in ChCl system and ChCl-free system. Based on the results, it shows that the characteristic of ionic liquids influences enzyme activity in reaction which can decrease or increase it. So, it needs to do further research about choline-based ionic liquids to increase enzyme activity.

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Indonesia as one of the world largest maritime country has very huge natural resources including microalgae. However, recently the analysis of potential local strain microalgae is still few to be studied. Whereas, the microalgae can be develop as biodiesel and an excellent solution to overcome the depletion of fossil fuel. This research was aimed to study microalgae species of local mix culture of microalgae isolated from Glagah and their lipid profile. The identification of microalgae species was done by observation under light microscope, while lipid profiling was done by measuring the lipid total using Nile Red Staining and the fatty acid profiling was done by using GC-MS method. Results showed that Glagah Consortium Microalgae was composed by six species microalgae including Cyclotella sp., Cylindrospermopsis sp., Golenkinia sp., Syracosphaera sp., Corethron sp., and Chlamydomonas sp. which could produce fatty acids suitable for biodiesel. The lipid content of the mix culture was 1.25% which composed by 51.27% SFA, 33.42% MUFA and 11.80% PUFA indicating that the mix culture of Glagah consortium was prospective as local biodiesel source.

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Recently fossil fuel still become a main source for energy and chemical platforms. In order to substitute fossil fuel with renewable resources, biomass conversion become a promising technology to convert biomass into bio-energy and bio-chemicals. Sugarcane bagasse (SCB), as one of potential biomass, available abundant in Indonesia and its economic value can be improved with conversion of sugarcane bagasse into syngas using gasification process. This process consists of four steps: drying, pyrolysis, oxidation-reduction and oxidation reactions. The aim of this paper is to study experimental work of pyrolysis-gasification of sugarcane bagasse interpreted using model of one-step global single reaction to obtain reaction kinetics of pyrolysis in the mechanism of pyrolysis-gasification of sugarcane bagasse .Before used as raw material in gasification, sugarcane bagasse will be treated with dry-torrefaction at a temperature of 150 0C. And from this study, there are found two steps of pyrolysis in SCB, the first step is pyrolysis reaction in rapid zone and the second is slow zone of pyrolysis. Rate of pyrolysis reaction, both rapid and slow pyrolysis, are influenced by the composition of biomass i.e., composition hemicelluloses, cellulose and lignin. While, dry torrefaction of SCB gives better thermal decomposition than raw SCB, increasing composition of lignin in SCB, reducing endothermic phase of celullose decomposition and increasing exothermic phase of lignin decomposition. Torrefaction of SCB also gives better kinetic reaction of pyrolysis than SCB0 which stated in constanta of reaction and order of reaction of pyrolysis. In rapid pyrolisis, value of constanta of reaction (K) of torrified-SCB is 17.167 while K of raw-SCB is 15.348 and order of reaction n is 5.245 for raw SCB and 5.040 for torrified-SCB. In slow pyrolysis, value of K is 0.065 for raw-SCB and 0.145 for torrified-CBT while order of reaction is 0.356 for raw-SCB and 0.553 for torrified-SCB.

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This paper describes the characterization and leaching behavior of precious metal present from electronics scrap to obtain liquor which can be treated through hydrometallurgical techniques to purify the metals. The results of this study points out the technical feasibility of the recovery of the metals. The blank sample was characterized by X-ray florescence. This paper will also present the results of hydrometallurgical extraction experiments, which allow the recovery of rare earth element. Inductively Coupled Plasma–Mass Spectrometry (ICP-MS) was used in order to determine the element composition in the leaching process in term of molarity, temperature, and acid solvent. Two leachants were compared (sulfuric acid and hydrochloric acid) at different molarity (1 M, 2 M and 5 M) and different temperature (room temperature, 50 0C and 100 0C). It was found that sulfuric acid leaching was very promising as a leachant for recovery of Fe, Cu, Si, Ti and Nb metal at room temperature . At higher concentration, hydrochloric acid allowed the leaching up to almost 40% of Ti, 60% of Nb and impressively 200% of P more than H2SO4. The results shows that the hydrometallurgical recovery of precious metals present in permanent magnet is a technically feasible.

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In sheet metal forming operations, the most deleterious defect are wrinkling, tearing, necking and springback. Wrinkling of cups drawing was simulated using the finite element method (FEM). The fem code Auto form was used in numerical analysis. Wrinkling phenomenon is affected by the mechanical properties of the blank sheet material, contact conditions, blank holder force (BHF) and the geometry of the punch and dies. The wrinkling prediction is difficult to perform due to the highly sensitivity of the parameters. The effect of parameters of BHF and friction coefficient in the cup drawing process are studied. The small variations of the parameters can result in widely different wrinkling behaviors. The objectives of this paper are to investigate the effects of lubrication and blank holder force on a dome wrinkling behavior. The experiment was conducted in lubricated condition, without lubrication and BHF variations of 1, 3, 5 and 8 kN. Two different blank sheets of Aluminum and Steel have been selected. The result shows that the dome wrinkling generation was influenced by blank holder force, while the lubrication did not give different result.

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Different treatments of SnCl2 were utilized as a catalyst to synthesize poly (lactic acid) through direct polycondensation in solution. These treatments were in (i) a hydrous form (SnCl2.2H2O), (ii) an anhydrous form (SnCl2) and (iii) an impregnated form (SnCl2/g-Al2O3). The polycondensation was done at 138 0C and in nitrogen atmospheric with flow rate of 100 ml/min. L-lactic acid and a catalyst (1 wt. % of l-lactic acid) were mixed in solution of m-xylene and reacted in 500 ml flask. The maximum molecular weight (Mw) of obtained poly (lactic acid) was 104,392 Da after 72 hours with catalyst SnCl2/ ?-Al2O3. Grafting of obtained poly (lactic acid) chains into glycerol supported by hexametyl diisocyanate (HDMI) was successfully done. The grafted poly (lactic acid) had an average molecular weight three times higher than that of obtained poly (lactic acid). Infra-red spectra showed that the poly (lactic acid) can be produced using this synthesis technique and has molecular structure arranged mainly in amorphous phases. The maximum degree of crystallinity was found at 12.91% (DSC) or 14.56% (XRD) for obtained poly (lactic acid) with catalyst of SnCl2/ ?-Al2O3. These results showed that impregnation SnCl2 on ?-Al2O3 enhanced its performance to polymerize l-lactic acid and able to graft it into glycerol.

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In the classical Wilson’s economic ordering quantity model, it was assumed that the goods can be held infinitely for future demand. However, in practices, as most items we deal with such goods required considering the factors of short shelf life, then some suppliers tries to reduce their lost by offering incremental quantity discount. This paper will try to combine and modify several basic models of deterministic inventory control to design a model for deteriorating item by considering quantity incremental discount under permissible delay in payments. Heuristic approaches used to solve the models. A numerical example has been solved to illustrate the model.

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Micro-milling technology is improving to fulfill the micro-product demand in term of shape, accuracy, complexity, etc. Although commercial micro-milling machines are available, however a low-cost micro-milling machine is still required to enhance the micro-milling technology. Hadia Micromill-5X is a NC micro-milling machine prototype. Each axis of the machine are moved by a stepper motor. The motor is driven by sending pulses corresponds to NC point. The linear axes movement accuracy was measured by using a Laser Interferometer. In producing micro-parts, an integrated CAD/CAM software is used to design the micro-part and planning the manufacturing process. The CAD/CAM software produces a CL file which then transformed to NC file through a postprocessor. Then, the NC file executes by Hadia Micromill-5X to perform a micro-milling cutting process. Contoured thin-wall with maximum thickness of 50 µm and 150 µm, micro-impellers with a diameter of 2 mm and 3 mm were successfully machined.

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Numerous studies have considered penalty as part of lease contract stipulation, which incurs whenever equipment downtime exceed a predetermined level. Under this stipulation, lessor would then choose maintenance effort level just enough to hinder them from penalty. Since it is used for business purpose, lower equipment downtime would always preferable for the lessee but necessarily for the lessor. Lower downtime requires higher maintenance effort, thus higher cost. To make sure that lessor is putting their best effort to achieve the lowest downtime possible a proper incentive needs to be determined. This paper considers not only penalty but also incentive as part of contract stipulation. We adopt the perspective of lessee and build decision making model for determining lease contract price and performance based payment scheme to be offered to the lessor. Principal agent theory is used as modeling approach due to its ability to simultaneously consider the interest of both parties involved.

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Six Sigma method is one method of management approaches aimed at making decisions based on facts and based on the use of data using special tools and methodologies. This study deals with the methodology of Six Sigma approach in reducing the incidence of occupational accidents in the collection of solid waste in South Jakarta. The fundamental problem-solving approach is done by following the DMAIC (Define-Measure-Analyze-Improve-Control) in order to reduce the process variation and improvement process results. Analysis of the problem also using some tools such as Pareto diagrams, Fishbone diagrams and Analytical Hierarchy Process. Research conducted at the Department of cleanliness of South Jakarta as research subjects in order to analyze and determine the cause of the problem of workplace accidents solid waste collection. Results show DPU approximately 0.22 and approximately 220000 and a target DPMO sigma level is 3.554. Moreover, the results of AHP calculation using Expert Choice software indicate the most significant factor is the method with 0.392 weights. In addition, the sub-causes of the most dominant in workplace accidents collecting solid waste, such as, lack of safety equipment around 0.833 and pleasant environment around 0.833.

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Investment Casting (IC) is a producing method of high quality casting. It is useful to generate complex geometry in casting product, which cannot be achieved by forging, machining, or machining process with excessive material usage. Currently, IC pattern is made of wax. The wax melts away during the molten metal pouring. In the past, it was stipulated that once a foundry used a wax pattern of particular grades, that it could not be replaced by another grade. This was to avoid the risk of dimensional variety of patterns, coupled with a basic fear of change. The pattern wax compounds have been chosen by foundries with numerous considerations, such as: historical record; the wax the only suitable compound at the time; professional recommendation; and copying from another foundry. Inappropriate wax injector’s parameter can create low quality patterns and a ceramic shell. Nowadays, there are wide ranges of material available as an alternative for the IC wax pattern, which in this paper initially highlighted using Acrylonitrile Butadiene Styrene (ABS) as a replacement of conventional pattern material. The pattern with ABS material can be created by Rapid Prototyping Machine (RPM) that is Fused Deposition Modeling (FDM) technology. The experimental outcomes are: there are cracks in the ceramic shell while using the smelting chemical method because ABS material pushed out the shell; perfect ceramic shell with ABS pattern smelting while using burn-out method; and this method can reduce three of seven steps or more efficient about 42.85% of the existing IC process.

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This paper considers five different projects in the perspective of manufacturing industrial sector. For evaluation and selection of these projects a set of six factors; realism, capability, flexibility, ease of use, cost and ease of computation are considered. Using Analytic Hierarchy Process (AHP), the global weights of five different projects are computed. In the proposed work, first, the pairwise comparison matrix is prepared for all the six set of factors under consideration using Saaty s scale. Then, normalized matrix is prepared to verify the consistency of pairwise comparison matrix and the priority weights are computed. Similarly, with respect to each factor, the pairwise comparison matrix and normalized matrix are prepared for all five projects. Also, the consistency index is verified for all the five projects. Finally, the global weights are computed for all five projects. Based on the findings of this work, it is concluded that the project one is most prioritized and project two is least prioritized.

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An experimental forced convective heat transfer analysis is done on magnetic micro fluid flowing through a copper tube in the presence of magnetic field for different mass fractions of magnetic particles, different Reynolds numbers and different Hartmann numbers. The flow is passing through the tube under a laminar condition. The experimentation has done under uniform heat flux and constant wall temperature cases. An increase in flow rate (Reynolds number) or Magnetic Field (Hartmann Number) or mass fractions of magnetic particles resulted in increase in the rate of convective heat transfer (Nusselt Number) for both the cases.

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This paper presents the results of the experimental investigation conducted at supersonic Mach numbers through converging-diverging nozzles. The experiments were conducted for correctly expanded cases and, for length-to-diameter ratio of 10 to 1. The area ratios were 2.56, 3.24, 4.84, and 6.25. The results presented are only for correctly expanded jets. From the results it is found that at lower Mach numbers and area ratios the efficacy of the control in the form of micro jets is only marginal and the control results in increase of base pressure for all the Mach number. For the first two lower area ratios namely 2.56 and 3.24, it is also observed that the magnitude is getting enhanced considerably from Mach 1.6 and beyond, but for the larger area ratios namely 4.84 and 6.25 of the present study the control results in decrease of base pressure for Mach numbers in the range 1.6, 1.8, and 2.0. When we analyzed and plotted the wall pressure distribution in the enlarged duct the flow remains unperturbed and attached with the suddenly expanded duct for both with and without control cases. For Mach 1.48 the flow field in the duct becomes oscillatory which; indicates that the flow in the duct is dominated by the waves and when the active control is employed suppresses the noise, and this peculiar phenomenon happens only for this Mach number. However, for Mach 1.8 and 2.0 the flow structure in the duct remained oscillatory for the entire region of the duct, and for rest of the Mach numbers it remained same even when the control in the form of micro jets are activated. Hence, it can be stated that the control with the micro jets does influence the flow in the duct wall adversely except at Mach 1.48.

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This research work reports the significance of influence of speed, feed and depth of cut on tool wear. In this study an experiments was carried out in kirloskar master 35- Lathe using work tool made up of ceramic with an Al2O3+TiC matrix and the work material is EN24 steel of hardness 48 HRC. Also, an attempt was made to fuse cutting force, cutting temperature and tool vibration (displacement), along with cutting velocity, feed and depth of cut to predict tool wear. In this work cutting force were measured by Kistler force dynamometer, cutting temperature were measured by Infra-red thermometer, tool vibration were measured by piezoelectric digital vibrometer and tool wear were measured by optical microscope. By Minitab software which is best tool for optimizing the cutting parameters such as cutting velocity, feed and depth of cut. The above study said parameters are optimized using DoE. The optimized cutting parameters using Taguchi method (L18 Mixed Design) were compared with Analysis of Variance (ANOVA) and Response Surface Methodology (RSM). In addition the results were verified with manual method for any deficiency. The above study revealed that the results obtained from ANOVA and RSM is closely matching with the results obtained from DoE.

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Film cooling can be used as an effective method of cooling the thrust chamber wall of a liquid rocket engine. A coolant fluid, typically the propellant, is then pushed through the shaped holes until it ultimately reaches the thrust chamber wall. The thermal properties, most notably the effective conductivity, of the coolant and geometrical parameters provide an efficient cooling mechanism for the thrust chamber wall. Film cooling effectiveness is used to express the film cooling phenomena quantitatively. Concluding from the literatures, film cooling effectiveness mainly depends on certain factors such as blowing ratio, injection angle, compound angle/orientation, L/D ratio etc. The present study is related to the numerical investigation of different hole shapes for film cooling performance, which is widely used for cooling of high temperature in the thrust chamber walls, nozzle walls and gas turbines. The adiabatic film cooling effectiveness values are determined computationally, downstream of cooling holes. Different hole shapes compared are cylindrical holes, elliptic holes and semi-elliptic holes. Apart from hole shapes other parameters have been varied. Other parameters include blowing ratios and orientation of holes. The blowing ratio ranged from 0.67 to 1.33 while the orientation angles varied from 00 to 450. Results are presented for the centerline and laterally averaged adiabatic effectiveness, normalized temperature distribution, and velocity vector field. These results show the interactions between the mainstream hot gas and the cooling jets, and how those interactions affect surface adiabatic effectiveness. Out of all these cases, the best results have been computed for the semi-elliptic hole configuration. Semi-elliptic hole utilizes half of the mass flow as in other hole shapes and gives nominal values of effectiveness. The computed results were compared with the benchmark experimental data of Yuen et al. This comparison shows the results generated to be reasonable and physically meaningful.

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Friction surfacing is an emerging surface engineering technology, an advanced process of great potential, especially in the field of repair and reclamation of worn and damaged components. The temperature field of Mechtrode (consumable rod) in friction surfacing, as a kind of thermal processing technology, is an important factor in the successful implementation of the process. In this work, the temperature model of mechtrode in friction surfacing is established. Using finite element method the temperature field of consumable-rod during the friction surfacing process is simulated. In this work low carbon steel (EN1A) is used as a Substrate Material and Aluminum 6061 Alloy is used as a Mechtrode. Mectrode rotation speed is varying from 900 to 1500 rpm and the axial load applied is 10 KN. The deformation on the mechtrode and temperature values is presented. Ansys software is used for this analysis.

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In this study, experimental tests and numerical analysis are carried out on adhesive bonded lap joints and is compared with welded joints. The material used for the experiment is mild steel. Experimental tests have been carried out for adhesive bonded specimens to find out the tensile and shear strength of the joints. Epoxy adhesives viz. Bisphenol-A-(epichlorhydrin) epoxy resin, anaerobic adhesive, M-seal GP epoxy compound are used to find out the maximum load bearing capacity of adhesive bonded joints. The joints are modelled in Solid Works and analyzed using COMSOL Multiphysics software to validate the experimental results. Using Finite element methods, results were simulated to find von-Misses stress in joint region. The experimental stress-strain results are compared with those of the simulation results.

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Blackout restoration is important process in power system. It have so many strategies to restore the power system, Processing time is the vital role in Power system restoration. Here parallel power system restoration methodology computed by Virtual instrumentation and DAQ device as quickly as possible. In this paper deals with IEEE 39 bus system. Using graph theory to find the shortest path for each node, it will embed in the virtual instrumentation. This virtual model result shows the processing time to execute the restoration process.

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In the recent years, natural resins have received much more attention than ever before in the research community. The natural resins offer a number of advantages over commercial resins [1]. In the present communication a study on the synthesis and mechanical properties of Acacia resins reinforced with E-Glass fiber based polymer composites has been reported. Mechanical properties of intimately mixed Acacia resins reinforced polymer composites such as tensile, shear, adhesive and wear properties were investigated. Initially Acacia resin prepared was subjected to evaluation of its optimum mechanical properties. Then the natural fiber reinforced composite was cured under Ultra Violet radiation. Present work reveals that mechanical properties such as tensile strength, water resistance and wear resistance etc, of those natural resins increases to considerable extent when cured under Ultra Violet Radiation. It is also compared with synthetic resins.

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In this paper, the experimental process on electroless Ni-P/Ni-B-Al2O3(nano) composite coatings and influence of non-ionic surfactant were investigated. The coating thickness was improved by adding the polyethylene glycol hexadecyl ether (non-ionic surfactant) on electroless Ni-P bath. The purpose of using non-ionic surfactant is to improve the coating thickness on low carbon steel. Coating thickness was calculated by using weight analysis method. Surface morphology was studied using SEM analysis.

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This research work investigates the ILSS and 3-point bending performance of plane woven GFRP/epoxy laminate of six layers doped with carbon fiber fillers. The carbon fiber fillers are chopped into the size ranging from 5mm to 10mm.These carbon fiber fillers are mixed with resin in three proportions 0wt%, 1 wt%, 2wt% and 5wt% in order to investigate enhanced properties of the prepared laminate. GFRP laminate was prepared by hand layup technique assisted by vacuum bagging. The size of the specimen for the experiment was taken as per the ASTM standards for ILSS and 3-point bend test. The experiment was performed on Hounsfield machine having maximum load capacity of 50 KN and loading rate ranging from 1 mm/min to 50 mm/min. The experimental results concluded that by adding carbon fiber fillers there is 5% to 10% enhancement in ILSS and 3-point bending strength properties.

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It is well known that the problem of Noise and vibration is one of the major issues in the automobiles and particularly in the diesel engine vehicles. The diesel engine vehicle usage is been increased due to the fuel economy and mileage. But the main disadvantage is the vibration and noise that arises in the engine, whereas it is more in the diesel engine when compared to the petrol engine. It is well known that the power train is the main source of the vibration producing part in the vehicle and which is been mounted on the engine frame that supplies the power to the vehicle. The part that connects the engine and the chassis is the engine mount that plays a vital role in transmission of the engine vibration to the vehicle structure which has to be designed in such a way that the vibration and noise from the engine power train can be isolated, here we are going to use a semi-active hydraulic engine mount that reduces the vibration of the engine and subsequently do the modeling and analysis of the semi-active hydraulic engine mount and to compare with the mount characteristics of the other types of engine mounts that are available and conclude that the semi-active engine mount is one of the feasible component to reduce the vibration inside the cabin of the diesel engine passenger car.

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Engineering design is an iterative process that requires to be followed with all feasible design solutions in order to arrive at desired objective. Proper design of gear train has a significant place in power transmission applications. Traditional methods used in its design do not have ability in automating the process. Thus, an attempt to automate preliminary design of gear train has been accomplished in the paper. In this paper, the volume and load carrying capacity are optimized. Two different methodologies (i) Genetic algorithm (GA), (ii) Fminsearch Solver optimization technique are used to solve the problem. In the first two methods, volume is minimized in the first step and then the load carrying capacities of both shafts are calculated. In this study, the Genetic Algorithm is introduced for the optimum design of gear trains to solve such problems and we propose a genetic algorithm based gear design system. This system is applied for the geometrical volume (size) minimization problem of the two-stage gear train and the gear train to show that genetic algorithm is better than the conventional algorithms for solving the problems. Genetic algorithm is used for optimization by using a Matlab programs are used to solve the problem. For the optimization purpose, face width, module, and number of teeth are taken as design variables. Constraints are imposed on bending strength, surface fatigue strength and interference. The results are validated with the experimental results published in the literature and standard parameters of gear train.

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Flow inside pipes is extended applicable in various industrial sectors, from power plants and food industries to oil and gas companies and petrochemical procedures. In most of the cases corrosion and energy losses problems are mentioned, which are difficult to be faced due to the lack of data or information concerning the flow visualization, simulation and estimation especially at fluid flows inside sharp 90?pipes. In the present paper a flexible and accurate enough numerical approach is presented for Newtonian flows inside pipes with 90?curvature. The flow in the pipe is assumed as incompressible, laminar and viscous while the numerical results will be presented for various Reynolds numbers. Priority will be given in crude oil flows, type of Arabian light, where appropriate schemes for the prediction of the crude oil properties are developed. Existing empirical correlations as well as corresponded results by the literature are used for the needs of numerical results validation. Various results are presented concerning the flow variables, the energy losses and the stresses giving emphasis at the elbow area. It seems that near the elbow exit the stresses are increased, while maximum values are appeared on the innerradius. Additionally as the Re value is increased, more deviations occur within the stream eventually, leading to recirculation regions occurring in the pipe just downstream of the 45?section. Accurate interoperation of these deviations will show that the pressure and velocity of the fluid varies accordingly along the pipe.

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AISI 1040 stainless steel is a popular engineering material due to its wide application in the field of manufacturing, automobile and structural engineering. The motive of the research is to find the optimum process parameters for turning AISI 1040 under varying machining environment. Tungsten carbide tip tool is used for the experiment due to its high hardness and wear resistance. This model is used for the prediction of surface roughness and forces act during machining operation in different direction. The root mean square (RMS) it is found to be under expectable range. The surface roughness and forces were examine and it is found that predicted values and experimental values are close to each other which shows that the ANN model is effective for the prediction.

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The effects of Yb additions (0.3 wt.% and 0.8 wt.%) on Al-6.5Si-1Zn cast alloy was investigated using optical microscopy (OM) and scanning electron microscopy (SEM/EDS) analysis. The purpose of this research is to investigate the variations occurred in Si morphology and the formation of intermetallics with different Yb additions, as well as their effect on hardness value. The experimental results indicates that the Yb affected the silicon eutectic morphology of Al-6.5Si-1Zn secondary alloy, when 0.8 wt.% was added to the alloy and the coarse plate Si was modified into a fine fibrous structure. Two kinds of Yb-rich intermetallics were found, such as AlSiYb and AlSiYbMg. The hardness measurements revealed that the hardness values of base alloy were higher with the Yb addition.

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This paper characterized a fracture brass sample that underwent tensile testing. The aim of the case study is to characterized the brass sample with unknown microstructural arrangement and unknown elements composition. Tests were conducted based on the SEM imaging technique, EDX chemical analysis and XRD microstructural spatial analysis to indentify and correlate evidence on the sample. Examinations by morphological SEM analysis of tensile fracture surface shows that the brass sample exhibit a typical ductile like material fracture. XRD analysis confirmed the crystal arrangement of the brass sample is of a single FCC??-phase crystal arrangement. The brass composition is confirmed as 63Cu:37Zn wt% from the test conducted by the XRD analysis. The sample is suspected to undergone annealing for process history from the evidence on twinning on the cross-sectional SEM imaging. Thus it can be confirmed that material is a brass sample with 63Cu:37Zn wt% elemental composition with single FCC-phase crystal arrangement.

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