Application of Response Surface Methodology (RSM) in the modeling and optimization of the synthesis of alkyl polyglucosides (APG) is presented. Two different sets of alkyl polyglucoside from glucose (G) have been synthesized using an acid catalyst. Decanol (C10) and dodecanol (C12) are used as sources of fatty alcohol (FA), and the interactions effect of catalyst concentration, substrate molar ratio and reaction time on the density of APG is observed. The optimum density in decyl polyglucosides (APG-C10) synthesis was obtained at a catalyst concentration of 1.5 % (w/wG), a substrate ratio of 3 (mol FA/G) and a reaction time of 3 h. While in dodecyl polyglucosides (APG-C12) synthesis, optimum density was obtained at a catalyst concentration of 1 % (w/wG), substrate ratio of 2 (mol FA/G) and 13 h reaction time. The substrate ratio and reaction time are significant variables that influence the acquisition of APG density in both reactions. A quadratic polynomial model was fitted to the data with an R2 of more than 0.95. So that the model obtained can be said to be very significant.

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In this paper, a new approach for solving the system of coupled nonlinear partial differential equations that model fluid flow problems. The method, called the large parameter spectral perturbation method (LSPM) uses series expansion about a large parameter to decompose the system of partial differential equations (PDEs) into a sequence of ordinary differential equations (ODEs). The sequence of ODEs is then solved using the Chebyshev spectral collocation method. The LSPM is tested on a coupled three-equation system that models the problem of natural convection heat transfer flow through a magnetized vertical permeable plate for liquid metals. The accuracy of the LSPM is tested against the multi-domain bivariate spectral quasilinearisation method (MD-BSQLM) which is an approach that uses the quasilinearisation technique to linearise the nonlinear PDEs first and thereafter using the Chebyshev spectral collocation method to solve the governing equations on a sequence of smaller non-overlapping sub-intervals. The approximate numerical results indicate that the LSPM is an accurate and computationally efficient method for solving coupled nonlinear systems of PDEs defined over a large parameter interval. The numerical results obtained are presented graphically to show the effect of different parameters on the temperature, velocity profiles and transverse component field for different values of some of the parameters. Approximate numerical results for local skin friction, current density, and rate of heat transfer are presented in tabular forms. Residual error graphs are presented in order to further show the accuracy of the LSPM. We remark also that this paper aims at correcting the errors introduced by wrong transformations evident in the system of equations which have been chosen from literature for the numerical experiment.

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In this work, a new numerical approximation to solve the inverse point kinetics equation is presented. The integral of the historic of the neutron population density is discretized, based on the approximation of Euler-Maclaurin formula, considering an extra term in this procedure to obtain a better approximation using two Bernoulli numbers. Reactivity is calculated for different numerical experiments, with different neutron population density forms and different time steps. In order to validate the accuracy of the proposed method, we compare the results obtained with different numerical experiments reported in the literature. The results suggest that the method shown can be used in a real time reactivity digital meter.

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Forward error correcting codes have proven their usefulness over traditional communication channels and are of great benefit when conditions are normal. However, these codes perform very poorly over noisy or fading channels. Geometric Codes are classes of codes that outperform error-correcting codes over noisy channels.

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This paper presents the design, analysis and development of 30 kVAr DSTATCOM for compensation of reactive power in an 800 kW radial distribution system, feeding power to crucial loads of an educational institution. In this paper the study of radial distribution system is analyzed in terms of electrical power system of institute, power consumption pattern and tariff related issues. Made some conclusions to improve the system performance in terms of power factor and reduction in tariff. The DSTATCOM performance depends on the calculation of the reference source currents that generates the gating pulses of the voltage source converter (VSC) based DSTATCOM. For this purpose the control strategy adopted is IRP (Instantaneous Reactive Power) and SRF (Synchronous Reference Frame) theory and ADALINE is implemented in this system using MATLAB/ SIMULINK software. Generation of the PWM pulses triggers the IGBT of the VSC based DSTATCOM. This is achieved using DSP TMS 320 F 2812, a 32 bit processor that is programmed with CCS V8.0. The performance of the selected distribution system is analyzed experimentally in a hardware prototype to evaluate the effect of DSTATCOM. It is observe that the selected radial distribution system with DSTATCOM provides voltage sag mitigation, reactive power compensation and power factor improvement.

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High altitude, airborne, wind-energy extraction-systems are the only true alternative to carbon and nuclear produced energy. Airborne Wind Turbines are very efficient due to the possibility to search the altitude with the nominal wind velocity. Winds are very stable and fast at altitudes from 4,000m (13,000ft)-11,000m (36,000ft). It is possible have many airborne generators near consumers in restricted airspace regions. In the first two parts, autogiro solutions demonstrated to be fully feasible but not economically convenient. This third part of the paper deals with the design of a mass-produced fixed wing system for power generation. A fixed wing drone with a minimal airframe was conceptually designed for this purpose. The power generated is 220 kW at 13,600ft (4.15 km) as in the first parts of this paper. 13,600ft (4.15 km) is statistically the best altitude for high power availability and reasonable tether length. The drone is a simplified, unmanned ultralight aircraft. Therefore, it has all the advantages of ultralights: the simplified design rules, the vast knowledge and the mass-produced commercial parts and subsystems. Ballistic parachutes are also available for emergency. As in the first two parts of this paper, the airborne system is tethered to transfer the electric energy to the national grid. On ultralight-generator deployment, the reversible electric generator works as a motor and the airborne generator flies as an aircraft. This UAV (Unmanned Aerial vehicle) can take off from a very short grass field due to the low wing loading. The UAVs unfolds and holds the tether up the required altitude. In the climbing phase, the tether powers the aircraft using the national grid electric power. Once the airplane reaches the operating position, as the nose is turned into the wind, the wind provides the lift and the propeller is reversed to windmill. In this way, it is possible to convert the electric motor into a generator. The autopilot keeps the airplane in the desired position. In nominal attitude and altitude (100km/h@4,150m - 54kn@13,600ft), the rotor-generator outputs 0.22 MW. A preliminary design of a mass produced prototype is introduced in this paper with a cost per kWh competitive with fossil generated energy.

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In this work, an intelligent computer system capable of self-learning from RGB images to detect the disease of phytophthora in the cropping of cocoa is developed. The data used to learn the model are the set of images with the four stages of the phytophthora. The disease is caused by conditions of insufficient sunlight, rain, humidity, and temperature below 21 degrees Celsius. Brown spots appear on the cob, which in 11 days is mostly necrotic, easily spread causing large losses to farmers. The model construction was carried out with the acquisition of images, pre-processing, segmentation, training and classification. For system learning, a dataset of 1200 images of select cocoa crops in the study area was used. As a result, 80% of success with the developed model is achieved. This model is an import contribution because an intelligent model to detect the disease according to the literature had not been developed.

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Normally, isochronal tests are designed for flow periods of 4 hr since it is considered enough time to be under transient radial flow conditions. For elongated systems that time may fit on the linear flow regime period, then, the linear transient equation and the geometric skin factor must be included. In this paper the effect of the use of the geometric skin factor and the appropriate flow equation is compared. It was found huge differences if the IPR is inappropriately estimated. A set of equations for the estimation of IPR for homogeneous and naturally fractured reservoirs are presented for both pseudopressure and square pressure change.

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The article presents the results of a detailed description of the process of forming a high-frequency channel in the holes of case-screens of electronic means (REM), depending on the physical processes at different stages of the breakdown, taking into account the parameters of the external EMR. Analytical expressions have been obtained for the breakdown voltage and the time of formation of a high-frequency electronic channel in the holes of the case-screens. An expression describing the dynamics of the distribution of the electric voltage field during the interaction of a pulsed EMR with an ionized air media in the hole of the case-screen REM, which affects the implementation of the breakdown in the REM holes, has been obtained.

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In this article, the execution of constrained convection for two diverse half breed Nano liquids, viz., Cu (25nm) + Al (25nm) - refined water and Al2O3 (50nm)+ TiO2 (50nm) - refined water tentatively considered at vehicle radiator. Four diverse concentrations of cross breed Nano liquid within the extent of 1 - 5 vol. % were arranged by the augmentations half breed nanoparticles into the refined water as base liquid. The stream rate of coolant is changed within the run of 20 l/min - 70 l/min. Crossover Nano coolants display colossal alter within the warm exchange compared with the refined water. The warm exchange execution of Cu + Al - refined water cross breed Nano liquid was found to be way better than Al2O3 + TiO2 - refined water half breed Nano coolant. Besides, the Nusselt number is found to extend with the increment within the half breed nanoparticle concentration and half breed Nano liquid speed. The sort and estimate of cross breed nanoparticle play a critical part in advancement of warm exchange rate. The rate of warm exchange is expanded with increase in concentration of half breed nanoparticles for the primary sort around 35 % warm exchange change was accomplished with expansion of 5 vol % crossover nanoparticles. Besides the moment sort of cross breed nanoparticles expanded up 23 % with expansion of 5 % vol concentration.

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The aim of this work is to develop a new solder with a lower melting temperature, relative to standard palladium-based alloys, and improved technological properties using a three-component system additionally doped with boron. As a theoretical basis used approach to the analysis of complex systems developed by Professor Biront V. S. An experimental testing of boron was carried out at a content of 2.2 to 3.1 Wt% as a eutectic-forming substance in solder alloys of palladium. The methodology and technological modes of obtaining a new palladium-based solder alloy with a melting point of 1200 °C are also presented. Tests of the new alloy performed in the conditions of jewelry production gave positive results, on the basis of which its final composition was determined. This methodology was applied in the development of new compositions for noble metal alloys, which are protected by Russian and Eurasian patents.

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Abstract:

The best planning of electricity consumption is needed in order to sustain the increasing of development activities. An important way to achieve that goal is to have the best forecasting model that could accurately modelling the pattern usage of electricity by using the data from January 2009 until December 2017 and forecast for the electricity consumption from January 2018 to December 2018. The purpose of this paper is to apply two differences forecasting method to forecast the electricity consumption Universiti Tun Hussein Onn Malaysia (UTHM). This paper compared the performance of Holt’s Linear Trend method and Holt-Winters method both in long-term forecasting. The results show that both methods performing well and Holt-Winters’ with the lowest error compared to Holt’s Linear Trend method. The mean absolute error (MAE), mean absolute percentage error (MAPE) and root mean square error (RMSE) were calculated and pointed as a bench mark for both methods applied.

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Abstract:

The process of making batik traditionally takes a long time. From the many stages in the process of making batik, the stages of scratching usually take a long time. Scratching is to draw a batik motif either on paper or directly on a cloth. Because at this stage the batik maker must think of the desired motive idea, after getting an idea, then the batik maker will draw it on the paper or cloth. With the development of current technology and current science, it can shorten the time needed to create patterns and produce motifs that are more varied by using mathematical models or computational methods. In this Final Project, the Random Walk and Cellular Automata method will be used to develop octopus as a batik motif and produce patterns with many variations.

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