In a bid to reduce the incessant failure of buried pipes, due considerations have been given to the effects of external factors on the pipe structure while the effects of such factors on flow in buried pipes remain unknown. This paper employs the versatility of Comsol Multiphysics to numerically simulating flow in buried pipes in order to examine the effects of atmospheric temperature and soil loads on the temperature, pressure and velocity of fluid. The results show that the temperature, pressure and velocity of water in an unburied HDPE pipe at a distance 1.52m from the inlet are 303.9K, 101235.8Pa and 1.19m/s respectively. Considering the effects of atmospheric temperature on water at the same point in HDPE pipe buried at a depth of 1m in Sandy soil results in a temperature of 293.15K, pressure of 101780.4Pa and velocity of 2.651m/s. Combining effects of soil loads with atmospheric temperature results in a change of these values to 303.91K, 90457.81Pa and 823423.6m/s. The results reveal a need for due consideration of the effects of atmospheric temperature and soil loads on flow in buried pipes before fixing the operating conditions of the pipeline.

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This work deals with the determination of optimal gear ratios of three-step bevel helical reducers. To find the optimal ratios, an optimization problem was created and solved. In this problem, the minimal reducer cross section was selected for the target. Also, seven main design parameters counting the total ratio, the allowable contact stresses and the face width coefficients of all steps and the output torque were chosen for the examination of the effects of them to the optimal gear ratios. In addition, to estimate the weight of these parameters on the optimum ratios, a simulation experiment was carried out by programming. From the experimental results, the influence of the design factors on the optimal gear ratios was found, and an equation to find the optimal gear ratios was presented.

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Petrographic analysis using a polarizing microscope was carried out to determine the texture and minerals of Mount Gamalama's lava in North Maluku, Indonesia. Microscopic observations were made on seventeen representative samples. The results of these observations indicate that in general the lava is classified as an extrusive rock in the form of basalt. The mineral composition of the lava consists of phenocryst plagioclase and pyroxene set in the groundmass of needles and plagioclase microlites, pyroxene, opaque minerals and volcanic glass. Sericite mineral and iron oxide occur as secondary minerals. The general textures of the rock are micro aphanitic porphyry, inequigranular, and vesicular, while the special textures found are hyalopilitic, glomeroporphyritic, oscillatory zoning, and sieve.

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Stator drying is a process carried out in the repair of induction motors used in the oil industry. In this work, the development of a stator drying machine is proposed to have greater efficiency in the number of repaired motors to be put into service. The offered stator drying machine is robust and has electronic elements that support high current levels, such as SCR (Silicon Controlled Rectifier) used in power electronics. Power control is obtained by on-off control. In the SCR trigger control stage, a central device called Raspberry Pi is used. The user interface is an LCD screen (Liquid Crystal Display) that connects to the Raspberry Pi via USB port and communicates via serial. As a result, the drying time motor is less; and the number of stators ready to be put into operation is increased.

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Tidore Island is a small island which its domestic and non-domestic water requirements at 2018 was 125.21 l/sec and expected to be 167.98 l/sec by 2038. The existing data show the average of water source in the form of Deep Well in Tidore Island is 2.5 - 5 l/sec, in other words Tidore Island needs around 60 Deep Wells. The plant of Green Water Supply Concept is to make Shallow Wells with depths between 24 - 40 meter below ground level and pump them into 500 m3 capacity reservoirs at an altitude of 469 meter and Micro Hydro Water Turbine which installed at an altitude of 134 meter. The potential of ground water in Rawa Lembah Kramat is around 55 l/sec, make it suitable to be planted with a capacity of 50 l/sec water turbine and estimated will produce 105 KW electrical energy if it’s total efficiency is 65% and it’s difference falling altitude is 346 meter. The Calculation show the electrical power requirement for 50 l/sec capacity 120 meter head pumps is 98KW, this means the electrical energy generated by micro hydro turbine is able to meet the energy requirements of raw water pumps.

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Besides functioning as water infiltration, biopore infiltration holes (BIH) also work as composting of organic waste. This study aims to analyze the effect of raw material composition on the quality and quantity of compost using the BIH method. Composting was done in duplicate in the yard area with clay soil type and water infiltration rate was 0.3 cm/hour. The holes were made with10 cm of diameter, 100 cm of depth and the distance between the holes are 50 cm. There were 4 composting variations i.e. 100% yard waste, 100% food waste, 50% yard waste and 50% food waste, and 70% food waste and 30% yard waste. The analysis was done toward compost maturity, compost quality (physical and macro elements) and compost quantity. The results showed that all variations of compost raw materials had met the standard of maturity and quality of physical and macro-compost elements according to SNI 19-7030-2004 regarding compost specifications from domestic organic waste, with composting time ranging from 65-75 days. Composts that consist of food waste and yard waste can accelerate the composting time by 5 days, compared to compost without mixture. The best variation in terms of maturity, quality and quantity is a variety of raw materials consisting of 50% yard waste and 50% food waste.

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The objective of this research is to assess the effects of climate and land use changes on the amount of runoff that flows through 3 types of hydraulic structures: pipes, R. C. box culvert and bridges using a SWAT model and Rational Method. Hydraulic structures in Roi -Et Province, Thailand were selected as a case study. We also a reviewed the suitability of the hydraulic structures by comparing their cross-sectional areas obtained from the SWAT model and Rational Method with the original drainage structures sizes obtained from the survey data. The results showed that runoff volume estimated from the SWAT model was greater than with the Rational Method, which used the graph of the rainfall intensity-duration-frequency curve (IDF Curve). However, the SWAT model evaluated runoff using the simulation of climate scenarios with the data from the PRECIS model under the emission conditions of B2 and did consider the current land use data. Therefore, the resulting cross-sectional areas of the hydraulic structures evaluated from the SWAT model have more hydraulic cross-sectional areas than the estimated cross-section by Rational Method and cross-sectional area determined from the survey data.

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The deployment of Device-to-Device (D2D) communication in the millimeter-wave (mm-wave) band has shown the potential of significantly improving performance in terms of capacity, energy efficiency, and transmission latency. The high mm-wave frequencies offer a broader spectrum, compared to the current cellular networks, which enhances the deployment of highly directional antenna arrays to reduce interference problems. However, deployment of D2D communication in the mm-wave band is faced with a challenge of signal blockage by obstacles. In addition, if users are subjected to some mobility, there will be beam misalignments between the transmitter and the receiver and frequent monitoring and handovers. In dense D2D communication in the mm-wave band, there is interference between the multiple D2D devices. All these cases increase interference in the mm-wave D2D communication network. Therefore, an effective mechanism needs to be developed to reduce this interference to maximize the D2D user capacity by allocating resources effectively. The paper aims to formulate a joint uplink scheduling and resource allocation scheme to maximize the user capacity in a MIMO-enabled mm-wave D2D network with user mobility. The developed mm-wave D2D model integrates Filter Bank Multicarrier/Offset Quadrature Amplitude Modulation (FBMC/OQAM), MIMO Space-Time Coding (STC) and Spatial Multiplexing (SM) which are implemented separately and their performance compared. The developed mm-wave D2D model is simulated and its results compared with the conventional Orthogonal Frequency Division Multiplexing (OFDM) scheme. The results indicate that the FBMC/OQAM outperformed OFDM by an average factor of 2.03 times for I=64, LOS, 2.53 for I=64, NLOS, 2.08 for I=256, LOS, 2.45 for I=256, NLOS, 2.08 for STC, LOS and 2.30 for STC, NLOS.

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In this paper, an attempt to implement an optimal complex multiplier using the “Urdhva Tiryakbhyam” Sutra of the ancient Indian Vedic Mathematics is presented. Signal Processing is based on mathematical analysis of complex numbers. Many DSP operations are based on complex operations like Fast Fourier Transform, z-transform, linear systems, multimedia applications, and telecommunications. The multiplier determines system performance as it is the slowest element and generally occupies a large area. Due to such conflicting constraints designing a complex multiplier has always been a challenge with significant tradeoffs. The proposed 16-bit Complex Multiplier using Vedic Multiplication is coded in VHDL, simulated and synthesized in Xilinx Vivado 2016 Software and compared to a standard Booth Complex multiplier.

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In this paper we investigate a method based on machine learning to identify types of motor vehicle traffic violations with image processing techniques to support electronic traffic law enforcement. Machine learning is a machine learning method that performs well when applied to data outside of the training set. In this study, data collection was carried out using a camera with a resolution of 13 megapixels. This data processing carries out a training process so that it requires high quality hardware such as a laptop / computer to get a result that can predict objects well. In this system it uses the CPU to train a model where the data is relatively small. The output in this system is a traffic violation image taken by using a camera. This system will work if a vehicle violates traffic, such as a violation of not wearing a helmet for motorcyclists and passing road markings. The system formed is a training result model with a total of 100 000 steps with 32 and 16 batch sizes, namely in the form of an inference graph consisting of a checkpoint file, frozen_inference_graph.pb, and there are 3 ckpt-model files. The accuracy rate of the model obtained ranges from 70% to 96%.

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The proposed genetic algorithm could solve the problem of task scheduling with a new initialization strategy to generate the initial population and new genetic operators to ensure best task–resource mapping that preserves good characteristics of the found solutions. Genetic Algorithm for Task Scheduling (GeneTaS) uses bio-inspired genetic algorithm to find an optimal schedule and adapts new fitness function to find the suitability of task and resource pair for best allocation. The use of evolutionary operators; crossover and mutation are found to move the solution very close towards optimality. The proposed algorithm is implemented using Gridsim, a simulator for task allocation problems and tested with arbitrary task graphs that are generated using DAGitizer. In the experimental setups thousands of arbitrary task graphs are used and it is observed that the results of the proposed GeneTaS algorithm is found better than the compared scheduling algorithms, when scaled on performance metrices namely; makespan, resource utilization and speed up.

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University websites are vital for students as well as faculty member for providing updated information. These websites can be accessed by general public for accessing certain piece of information. Hence, the role of university website become critical, therefore, usability becomes significant. Various interaction problems have experienced by the users while accessing university websites. To minimize these interaction problems different usability evaluation techniques have been adopted lately. Instant paper compares two usability evaluation techniques named questionnaire based (QB) and focus group (FG) by performing three user studies for evaluating the university websites. These techniques have been applied to evaluate and compare usability factors; efficiency, learn ability, memorability, satisfaction and error. The results have been verified using WAVE accessibility tool and validated by ANOVA. The results have shown that the focus group testing technique performs better than questionnaire-based testing technique in terms of efficiency, number of errors, learn ability and satisfaction.

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Abstract:

Higher education in Colombia since 2000 began to consolidate a training model oriented towards the competitive transformation of the student, in which processes are focused on problem-solving, which implies not only knowing the problem but also its conceptual and real approach. This trend has been structured over 20 years in what is known as competencies-based training and corresponds to the current state of higher education programs in the country. Although this approach has had a high degree of identification with the work environment, the truth is that the skills, knowledge, and abilities generated by the model are also applied to organizations and/or institutions. This article describes the design model of a specialized competencies-based software tool. The tool is part of the specialized training strategy of the research group and corresponds to the first of an integrated system of specialized research training. The design contemplates key elements at the pedagogical, didactic, and software engineering levels. The design architecture is made up of four stages which characterize each one of the tool's creations stages: educational design, computational design, production, and application. In the prototype, the problem of autonomous navigation of robots has been addressed, specifically, the implementation of a decentralized algorithm of the research group inspired by bacterial interaction. The preliminary evaluation of the tool has been advanced with undergraduate students linked to the research seedbed of the research group.

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