Generally, Optimal Power Flow is a problem of power system having differentiable objective functions. However, in the present restructure electricity power in form competition the generator company will offer its energy price in form non-differentiable function. Determining the winner of bidding must be done through optimal power flow with the non-differentiable objective function. So energy price falls in minimum condition and the optimal results can be applied directly to the system. This paper proposes a simpler method and fast which is Multi Dimension of Coarse to Fine Search Method to solve the Optimal Power Flow with non-differentiable objective function. The Method has been tested on the Java-Bali power system, 25 buses with 8 generator buses, and the results are compared to the results for differentiable objective function. This method is simple, and relatively fast in term of processing time, and also always gives a convergent result, so it will be more suitable to solve the Optimal Power Flow problem on the large scale power system in the future.

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The future word-wide production of magnesium metal is projected to increase substantially over the next decade and beyond, basically as a response to the perceived requirement to reduce fossil fuel consumption with a simultaneous reduction in the generation of greenhouse gases. Bittern is considered as a hazard liquid waste to environment, causes massive environmental problems; but it also has many uses in industry and agriculture, as well as being used for production of magnesium and other chemicals. Technology processes combining both were proposed to recover pure magnesium oxide from bittern by precipitation techniques using solution of sodium, or ammonium hydroxide, or oxalic acid. The production of magnesium metal is technically challenging, as well as having relatively high production costs. There are recent methods of producing magnesium metal from oxides involve high temperature reduction, and electrolysis of molten magnesium chloride and other applying laser with solar energy.

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Capillary pressure and relative permeability are key parameters that govern the fluid flow in geothermal reservoirs. Relative permeability data are used to predict the most effective hydrocarbon displacement mechanisms and the most efficient methods for extracting oil or gas from the reservoir. Determination of capillary pressure and relative permeability are traditionally conducted in the laboratory; however, in many cases these measurements are expensive, difficult, and time consuming. Theoretical models show that capillary pressure and relative permeability could be inferred from resistivity data. In fact, if one of these three parameters is known, the other two can be determined. In this study, laboratory measurements of the resistivity index, capillary pressure, and relative permeability were conducted on samples from two oil fields representing Libyan sandstone (A) and carbonate (B) reservoirs in order to review the analytical mathematical models correlating these variables. The results of the relative permeability calculated using these models were analysed and compared with experimental data obtained in the lab. The results showed that permeability can be calculated from experimental data of either resistivity index or capillary pressure. Good matching was observed between relative permeabilities and those calculated from with experimental data.

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This paper describes and implements the numerical Runge-Kutta method for solving stochastic point kinetic equations. The mean and variance of neutron and delayed neutron precursor populations are calculated for different time steps for constant reactivities. The advantage of the proposed method is that it requires the development of few derivatives and has low computational cost, as it does not require the square root calculation of a matrix. The numerical results obtained indicate that the method is efficient and precise for the study of stochastic point kinetics with constant reactivity.

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In this article, a 4 x 4 element wide band (UWB) multiple-input multiple-output (MIMO) antenna is proposed. The total size of the proposed antenna is 40 x 40 x 1.6 mm3. The antenna elements are placed orthogonal to each other. A CSRR shape like elliptical slot is etched on the radiating element to achieve dual band notch characteristics at WiMAX 4.8 GHz regions. The proposed antenna operates from 4.8 to 9.2 GHz, which exhibits a reflection coefficient of S11< -10 dB and has isolation better than 20 dB. Envelope correlation coefficient (ECC) mutual coupling performance of the presented antenna which is around 0.01 to 0.02 at the operating bands.

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This paper is about the development and implementation of an electromagnetic transducer in harvesting kinetic energy from an octopus ride. The kinetic energy harnessed from the octopus ride by the electromagnetic transducer is stored in a 1F, 5.5V supercapacitor. The voltage is stored in the supercapacitor is regulated to approximately 4V by a conditioning circuit which uses an LM393 comparator. This research aims to utilize an alternative source of energy to reduce the cost and expenses in maintaining an octopus ride system.

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Economic development in the Central Sulawesi Province has been increasing since 2007 so that it has an impact in increasing infrastructure development. For this reason, human resources are needed, one of which is skilled construction workers. In fact, skilled construction workers in Central Sulawesi Province still lacks competence in accordance with his skills and also does not yet have a skills certificate. Training for skilled construction workers is mostly done but the results have not been maximized so that they are unable to compete with skilled workers from outside the province. Therefore the purpose of this study was (1) to find out the application of training models for skilled construction workers that are based on the conditions in the Central Sulawesi Province; (2) to find out the results of testing the application of the training model for skilled construction workers in Central Sulawesi Province. The study used a quantitative, descriptive-correlational approach. The study population was skilled workers who had attended their skills training in Central Sulawesi Province. Data collection used structured interview techniques and the results of primary data were calculated using statistical calculations. The research results concluded, that: (1) the application of a skilled construction worker training model was made using the Project-Based learning model which is in accordance with the conditions of the Central Sulawesi Province that has scattered project locations; (2) the results of the training trials using the application of the accelerated skilled construction worker training model in Central Sulawesi Province received a Good score (with an average value 81, 9).

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The article presents the results of mathematical calculations of the temperature field of a thermophysical cylindrical cell. According to the obtained results, the validity of the choice of geometrical parameters of the thermophysical cell and the calorimeter is proved. These results have been used in automated devices to measure the thermophysical characteristics of a wide variety of materials.

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The construction and grinding operating principle of meat grinders should have minimal effect to meat losses. This paper presents the engineering calculation of the cutting process of meat grinder. The experimental grinder consists of a frame, screw, gearbox, electric motor, V-belt transmission, casing, lock and hopper. The calculation algorithm of grinding process includes determination of the coefficient of use of the area of plates, cutting capacity and required power of the equipment. The operator scheme of mechanical processing of meat consists of the subsystem of preliminary grinding of meat and subsystem of mechanical processing of minced meat.

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Industries have a challenge to develop material which is less costly, high strength, more hardness and more toughness and can be drawn from the wastage of any agro product. Further, production of complex shapes in such hard to machine material by traditional method is another challenge. In this study, the 3weight% (wt.%) Cu particulates were added with 6, 8 and 10wt.% Rice Husk Ash (RHA) to prepare the reinforcing phase and Al 6061 alloy was used as a matrix to fabricate auminium matrix hybrid composites using stir casting method. The 1wt. % Mg was added to improve the wettability between the Al matrix and reinforcements. Electric Discharge Machining (EDM) is considered as an important process for machining of such kind of materials. The objective of this work is to investigate the effect of different factors like Workpiece electrode (W), Peak current (I), Voltage (V), Duty factor (t), Pulse-on time (Ton), and Flushing pressure (P) with brass electrode on metal removal rate (MRR) on the machining of aluminium matrix hybrid composites by EDM using Taguchi’s approach. The L27 orthogonal array (OA), for the six factors at three levels each, was opted to conduct the experiments and ANOVA and S/N ratios were applied to identify the significant parameters and optimization of EDM parameters for maximum MRR. The S/N ratio response graph clearly indicated that MRR decreased with increase in the wt. % of RHA. It is also reported that MRR increased significantly with an increase in discharge current. The Scanning Electron Microscope (SEM) was used for microstructural characterization of machined specimens.

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The effects of vortex behaviour on the aerodynamic performance of airfoils have been widely discussed over the years and serve as motivation for many research studies. This study takes two symmetrical airfoils into account, namely NACA 0012 and NACA 0024. Computational fluid dynamics simulations carried out involve low Reynolds number air flow over the airfoils at several angles of attack. The attention is given mainly on the separation bubble and vortex shedding phenomena, and the effects of vortex behaviour on airfoils’ aerodynamic performance as represented by lift and drag coefficients. The results show that the vortex-influenced velocity curl shows alternating vortex behaviour along the airfoils’ surfaces and at downstreams. The angles of attack influence such behaviour by developing specific separation bubbles with contrasting fixed points, in particular those along the airfoils’ surfaces.

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Abstract:

The aim of the present study was to evaluate developed screening tools on autism students’ as early detection detect early signs especially on visual for ASD children. Early intervention in autism spectrum disorder (ASD) improves outcomes, but treatment access depends on early identification. Method of collecting data was using tool, observation and interview. Design stage produces flowchart and storyboard and development stage produces learning media with conceptual characteristics presented through materials equipped with visualization in the form of videos, pictures, sound and text. The results of this research is there is a positive score and feedback from children with autism. Besides that, children with autism are easy to focus using this tool. Recommendation of a screening for autism disorders in practice when concerns from parents or family are not raised, challenge the quality of the instrument and the overall screening procedure. The benefits of early ASD screening and detection must be weighed against the risk for false positive test results causing parents unnecessary worry.

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Practically all real control objects are characterized by a certain spatial extent. In this regard, the controlled values of such objects depend not only on time, but also on the distribution over the spatial domain occupied by the object. The changes of controlled quantities, both in time and in space, are described by partial differential equations, integral, integro-differential equations or systems of equations of the most diverse nature. Compared to systems with lumped parameters, the class of control actions is expanding in principle. The number of control actions can include space-time controls, described by functions of several arguments - time and spatial coordinates. The structural representation of systems and the representation of distributed objects in the form of complex transfer coefficients for eigenfunctions greatly simplifies the problem of distributed systems analyzing, but can be used if there is a solution to a boundary value problem. To solve practical problems, most often, finite-dimensional approximation of distributed systems is used, which is based on finite-dimensional representations of partial derivatives based on the method of “grids” and “direct”, using Fourier series and Taylor series. The representation of discrete control actions in the form of delta functions allows one to investigate the class of systems with distributed parameters, for which there is a fundamental solution in the form of expansion in eigenvector functions of the object operator [1, 4, 9]. The study of the control actions discretization parameters influence on the regulation process allows the regulation of nonlinear discrete systems in the relay mode. The proposed work considers systems with distributed control objects. Three spatially distributed mathematical models are built. A closed-loop control system for the temperature field of a spatially distributed control object was synthesized. The frequency surfaces of all proposed regulators are constructed. A new method for analyzing the stability of spatially distributed control objects has been proposed.

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AC electrical properties were studied using the AC impedance technique. The electrical properties of thin films made of poly (ethylene oxide) (PEO) dispersed with dopants fixed amount of carbon black (0.1wt. %) were used in this study. The prepared films by casting method have been electrically. The present study has studying the variation of AC electrical conductivity with frequency in the range (3 kHz - 5 MHz) for PEO with doped 0.1wt. % carbon black as compared to that case of the un doped PEO film, and determined of some physical quantities and parameters as AC conductivity, impedance, dielectric constant. The observed values of the impedance (Z), dielectric constant (e'), dielectric loss (e"), and AC-conductivity (s_AC) showed frequency and temperature. It was found that the dielectric constant and dielectric loss of the prepared thin films increase with doped (0.1wt. %) carbon black (CB) complexes and that it decrease with frequency according to polarization processes. The AC conductivity increases with doped carbon black, temperature and frequency.

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The utilization of by-products of oil and gas production, such as associated petroleum gas, weathering gases and others is one of the most urgent ecological problems in the oil and gas complex today. In this regard a reduction of the emissions of methane at gas processing facilities by using substandard weathering gases for heat generation was the aim of this work. A technical justification for the use of substandard gas was carried out in the work and an original flow chart for collecting, storing and using weathering gases was proposed and justified. Moreover an environmental and economic justification of the proposed flow chart implementation was given on example of one of the existing gas condensate plants in northern Russia.

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The movement of the flat section of the rod during the deformation is represented as a set of section's progressive movement with original, local to this section, coordinate system, the spherical movement of section and fixed to this section additional coordinate system related to the total beginning of coordinate systems. The rotational movement is characterized by three rotation corners around the axes of progressively moving coordinate system. The angles of rotation around transverse axes are recorded in the functions of transverse motions. For the equations of equilibrium of internal and external forces of the rod related to the local coordinate system of the rod we should have a matrix of direction cosines with certain angles between the local and the spherically moving coordinate system. The article defines the components of this matrix. Usage of this matrix significantly clarifies the stress-strain state of the rod system [1, 2].

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In order to increase the efficiency of the process of membrane separation of water-oil emulsions by microfiltration and ultrafiltration, the initial membranes are modified by physical or chemical methods. Physical methods of membrane modification include, in particular, ultrasound, plasma, microwave treatment, thermal treatment, radiation treatment in various media. Surface treatment of membranes can change surface topography, reduce or increase surface energy, and sometimes remove harmful impurities. The physical treatment of membranes leads to changes in the surface properties of polymers. In this work for increasing productivity and degree of separation oil emulsion was done modification of thin-film microfiltration membranes from nylon and polytetrafluoroethylene (PTFE) by microwave radiation in a range of decimeter waves. The following parameters at treatment were used: capacity - 1500 W, radiation frequencies - 2450 MHz, temperature - 24 °C, processing time - from 10 to 60 minutes. The microwave radiation treatment leads to a slight decline of membrane weights. Also after modification is increase a hydrophilic of surface of the PTFE membranes, but a hydrophilic -ylon membranes is decreased. As a result of processing microwave radiation of membranes is increasing unit treatment, both at the separation of the emulsion, the productivity is growing stronger. The degree of separation a model emulsion by nylon membrane after microwave treatment is decrease in comparison with initial membrane. The removal efficiency of oil is growing at 15% when emulsion is separated by PTFE membrane, the size of separated particles is reduced from 118 to 36 nm. Modified membranes can be used for separating an oil-in-water emulsion and oily waste water treatment.

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Modern economically advantageous technologies for cultivation of melons and gourds provide unconditional application of manual labor. Such operations include: weeding out protective zones and row spacing during the treatment of seedlings of plants, various types of harvesting of melon fruits, and also sorting them according to certain characteristics. The main task in the choice of technologies is to find the most labor-intensive operation that is performed manually and, taking into account the agro-technical conditions, determine the maximum allowable treatment area per person. These calculations were performed on the basis of the methodology for estimating energy consumption.

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In Nigeria and most African countries, power outage is not a new thing. Most people who can afford a backup source of power get one to provide power in case of power failure. The backup power source chosen for this project is an inverter. The need for a transfer switch that can automatically switch between the main grid and the backup source cannot be over emphasized. It is necessary to avoid human errors and reduce time wasted in switching in case of an emergency need. A simple high performance transfer switch was constructed using mainly relays for the automatic switching. The circuit was first tested on the breadboard to check for errors and test before moving it to the PCB. It was divided into three stages: the power supply unit, the voltage comparator and the switching system. After testing, it was soldered to the board and further tested stage after stage. The efficiency of the linear 12 V power supply was 66.3%. This kind of efficiency is typical for linear supply. The maximum load rating of this switch is 10 amps. This project has been able to provide a low cost with high performance switch that can be useful for both emergency and standby application. This research hereby suggested that switching power supply can be used in placed of the linear power supply to increase its efficiency and reduce the amount of energy lost as heat.

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A hypothetical investigation of the modal information based delamination location strategy has been displayed in this paper. In light of the eigenvalue issue and annoyance presumption of imperfection in modal response, the hypothetical premise of the modal data and natural frequency technique is set up. The extraction of delamination qualities from the modal data by means of Biorthogonal wavelet transform is outlined. At that point, the proposed strategy has been connected to Glass epoxy laminated composite plate tests with predefined delaminated segments. Finite element method displaying results are introduced to show the execution of the technique. The numerical outcomes propose that the utilization of the delamination marker gives a more powerful and unambiguous delamination recognizable proof than the sole utilization of the wavelet coefficients of the modes researched. Moreover, the delamination estimator predicts the delamination size to a palatable dimension.

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The confidentiality of information in the digital age is very important, one of which is the confidentiality of E-Mail messages so that they cannot be read by certain parties, especially E-Mails that are under the domain of companies or institutions where E-Mail admins can be read. The solution that can be given is to do the encryption and decryption process in E-Mail messages so that only those who are entitled can read the E-Mail message. One Time On is an algorithm that is suitable to be applied to the security of E-Mail messages because the encryption process is done with keys in accordance with the length of E-Mail messages and is very difficult to analyze.

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Green environment is a puzzling and stimulating concern that has received a considerable attention in today’s construction industry. The construction industry in Malaysia is seen to embrace green construction due to the project requirements that need to be adhered to achieve the certification for Green Building Index (GBI). It is important to note that the GBI rating tool was first introduced in Malaysia back in the year 2005 with the main objective of enhancing awareness among industrial players and encouraging sustainable construction in built environment. Therefore, the utilization of natural fiber like Cocos Nucifera Linn Fiber (CNF) in foamed concrete is considered as a useful option in making concrete as a sustainable material to overcome this problem. Thus, the main objective of this study is to perform experimental studies in order to discern the effect of CNF volume fraction on drying shrinkage foamed concrete. To achieve the objective of this research, 21 batches of foamed concrete mix were prepared. Three densities of 650 kg/m3, 1050 kg/m3, and 1450 kg/m3 were fabricated. CNF was used as additives in the present study at 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, and 0.6% by volume fraction of the total mix. The experimental results showed that the drying shrinkage for all specimens is significantly high in early age until 30 days and gradually increases. Meanwhile, the drying shrinkage of foamed concrete samples is significantly enhanced through the incorporation of CNF. In particular, 1450kg/m³ density of 0.5% CNF demonstrate the best outcome. Overall, it tends to be presumed that the incorporation of CNF in foamed concrete adds to better shrinkage resistance and have great embodiment that help to upgrade the strength of foamed concrete and enhance ductility.

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