查看更多>>摘要：Single-phase voltage inverters are used among others in relief supplies and DC-DC converters to the alternative middle tier. In these applications, the main purpose is to obtain a sinusoidal AC output signal whose amplitude and frequency can be controlled, as well as the low levels of THD. This document presents a comparative study of certain orders single-phase inverters techniques. The techniques used are studied; the results of the simulations will be discussed.
查看更多>>摘要：The present study aims to propose a method of carrying out the functional safety analysis to ensure the safety of the manufacturing process for weapon systems. The purpose of using weapon systems is to harm human life and destroy the property of hostile countries. Naturally, a weapon system involves explosives during its development and operation. As such, manufacturing processes for weapon systems have potential hazards of accidents that can cause fatal damages to humans or property. Some erroneous activities in the manufacturing process can produce dangerous results. For this reason, the safety of manufacturing processes in the defense industry domain is more crucial than other general manufacturing domain. To deal with such a safety issue, in this research, we propose a model-based approach to ensuring the safety of the manufacturing process for the defense industry. The proposal is primarily based on the concept of functional safety and includes the three steps: determination of safety integrity levels; selection of appropriate safety analysis methods; and execution of the analysis methods using SysML models. Using the results obtained in the study, one can identify the risk factors in a complex manufacturing environment in advance to take preventive actions against the potential loss that may arise.
查看更多>>摘要：The main objective of this study is to make thermodynamics analysis of different components of solar rice husk hybrid power plant with its modification of structure by implementing a Rice Husk Dryer between the Condensate Pre-heater and Air Pre Heater in order to feed dry rice husk to furnace and performance evaluation of power plant with respect to reduction of moisture content of rice husk using MATLAB, R2016a. The flue gas is passed to the Rice Husk Dryer, where the heat of flue gas is used to dry the rice husk before feeding to the furnace. Solar energy is limited to a 50% share in the daytime. In this research solar parabolic collector and Rice, husk feed is arranged in a parallel to produce steam. Feeding with dry rice husk in the furnace was found to reduce the heat loss due to heating moisture present in rice husk up to furnace temperature and also heat loss due to excess air supplied to the furnace for evaporating and superheating the moisture present in the rice husk. The increase in furnace efficiency, fuel efficiency, thermal efficiency and plant efficiency, reduction in specific rice husk consumption, reduction in excess air supply and decrease in rice husk consumption, etc. with respect to reduction in the moisture content of rice husk for the power plant are evaluated. The result showed that with the reduction of moisture from 10% to 90%, the power plant efficiency is to be increased by 6.97% to 64.86% for boiler pressure of 50 bar.
Abdullah GheathAli AlawamiNaowara AlarafiMona Aabdelrhman...
204-211页
查看更多>>摘要：In this study ten different asymmetric olefins, with very good yield 77-92% were afforded using Knoevenagel condensation reaction between different aldehydes such as benzaldehyde, p-methoxybenzaldehyde, p-chlorobenzaldehyde, p-nitrobenzaldehyde and cinnamaldehyde and substrates containing active methylene groups such as 2-(4-bromophenyl) acetonitrile and 2-(naphthalen-2-yl) acetonitrile in ethanol at room temperature, in the presence of potassium hydroxide as a catalyst. All the synthesized compounds were identified on the basis of melting point, TLC and NMR spectra. In addition, these compounds were tested against microorganisms such as gram-positive bacteria and gram-negative bacteria in comparison with different antibiotics and the results were shown activity against gram-positive bacteria and gram-negative bacteria where compounds (V) and (X) exhibited higher activity than others against all selected microorganisms.
查看更多>>摘要：In this study, using state-of-the-art optical simulation software, we design, simulate and quantify the comparative accuracies of two types of FBG-based optical sensing systems: one is designed for lengthy, multiplexed multi-temperature measurements, the other for single-point measurements. Results and discussion are made to analyze the comparative performances, particularly in terms of linearity and accuracy.
NETL
NSTL