Gongcheng Kexue Yu Jishu/Advanced Engineering Science

Abstract : In this paper a methodology is introduced that allows probabilistic analysis of functions (transformations) generally associated with production, while preserving the parameters of the original transformation and having those a physical meaning. The resulting probability density function is customized to the phenomena that the transformation represents, phenomena from any discipline, such as management, economics, engineering, marketing, manufacturing, and other sciences. In the case of instantaneous electric power analysis, it is done through probabilities with first harmonic of current and voltage, and phase shift Φ. The time samples are re-sampled according to a uniform probability density function, so it is possible to apply transformation of random variables over this uniform density function. Depending on intrinsic values of the signal (the harmonic distortion, phase, amplitude), the shape of the instantaneous power signal (the transformation) varies and therefore the shape of the probability density function too. The model or methodology stablished here is general but limited to one independent variable used with a uniform sample function..
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Abstract : Technological advancement in building incorporated photovoltaic (BIPV) has transformed the façade of the building into a generator powered by renewable energy sources. The BIPV facades are designed to provide energy production alongside traditional design goals such as aesthetics art and environmental control. However, the problem is that architectural design goals sometimes conflict with energy performance such as visibility and daylight versus maximum power output. In this context, the use of renewable energy sources such as solar energy seems to be worthwhile as they are numerous and have enormous environmental and economic prospects. This study aims to provide a new entrance to building design by enhancing a façade with photovoltaic to form aesthetic appeal and construction by studying the current situation of energy consumption. This research will give access to afford sustainable planning decisions that the use of photovoltaic energy in building façades is architecturally feasible to give an elegant design that arises from engineering creativity, satisfies the requirements of efficiency and economy, and is also elegant. in addition to that using a photovoltaic system is the best decision for different building types to become more self-sufficient and, ecofriendly, decrease carbon footprint and reduce monthly electricity bills..
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Abstract : Designing an optimal surfactant polymer design is very crucial and requires numerous laboratory tests that require infinite time, higher financial statements, and probably lack accuracy. Consequently, AI techniques have taken over, proving excellent accuracy levels with less time and lower cost. This paperwork is objectified to eliminate any laboratory work when it comes to generating an optimal surfactant-polymer design with the freedom to do multiple adjustments across the factors affecting the process and their responses in minutes and with financial ease. Consequently, a comparative study is done throughout this paper in order to have an optimum prediction for either factor affecting EOR recovery or their outcomes. However, this paper has traced the footprints of the previous experimental study by considering the critical-micelle-concentration of 1.25wt.% is the optimum alongside depending on the laboratory observations at evaluating the surfactant, the values of each factor, and its respective result under specific conditions i.e.: high-salinity. Nonetheless, the computerized observations have slightly deviated when it comes to the polymer concentration which altered everything afterward analytically and statistically, however it is realistic. The Design-Expert software was used to initiate this comparative study, it has shown promising outcomes as another XG concentration was predicted at 1871.61 ppm rather than the former 2000 ppm. This caused a difference between both the previous and present study. For instance, experimentally IFT chosen was 3.1 mN/m, contact angles chosen were 50.1° and 60.52°, viscosity chosen was 11.78 cp and the oil recovery factor percentage was 53% after SP flooding. Oppositely, the AI design shows an IFT of 3.0072 mN/m, contact angles of 49.75° and 59.53°, a viscosity of 11.99 cp, and an oil recovery factor of 51.41%. The model has shown high accuracy with the observation of R^2 reaching 0.9988 and standard deviation as low as 0.1121. The success of the proposed AI model would be a plot twist if applied to Egyptian oil fields due to the minor role of EOR in such regions..
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Abstract : Bedono Village of Sayung District belongs to Demak Regency and is situated on the northern coast of Central Java Province. This area has many rivers and other important habitats: mangrove forests and silty-clay beaches. These rivers transport sediment to the waters of Bedono. With the development, the construction of the Port of Semarang causes changes in current and sediment transportation patterns, leading to erosion and deposition of sediments in various areas in the waters of Demak. Therefore, it is crucial to study hydrodynamics and sedimentation characteristics in managing coastal resources in the region. The present research aims to model the hydrodynamics characteristics (current speed and directions) using oceanographic data on waves, tides, and bathymetry. The study was conducted between May and December 2017. The results showed that the wave height was between 0.5 - 1.25 m with an average wave height of 0.5 -0.79 m and the direction of the wave blowing west-east following the current season. The average current speed in the western season is 5-15 cm s-1, and the average current speed in the east season is 5.9-8.8 cm s-1 with the direction of the current following the wind and the prevailing current. The average tidal height that occurs in the waters of Bedono Demak is an average tidal height of 0.6 m, with the highest tide of 0.9 m and the lowest of 0.3 m. The dominant sediment characteristic is dominated by silt and clay..
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Abstract : Many lightweight materials are required to improve many advancements such as the travel distance of vehicles. Composites are required to be light, strong and if possible, economical so it may be used to increase the lightweight properties of vehicles and other lightweight applications. Indonesia has a variety of natural fibers such as rice straw and Ijuk palm fibers that are abundant and relatively cheap. This study aims to understand the character of the fibers when utilized in composites. Composites are made from resin with different contents of carbon fibers, rice straw fibers and Ijuk fibers. The products are then tested using load, tensile, impact, density and porosity tests. Samples showed that composites are able to withstand a maximum load of 680.79 kgf and tensile test of 12.90 N/mm² from straw fiber composite and 768.24 kgf and tensile test 14.47 N/mm² from Ijuk composites. Impact tests have also shown a maximum impact of 0.189 J/mm² and 0.132 J/mm² for rice straw and Ijuk fibers respectively. There are different variations in density and porosity due to the size of the fibers. The values indicate that it is possible to manufacture the natural fibers and carbon fibers into composites..
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