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51.
Wireless Personal Communications - Applications of wireless sensor networks (WSNs) are increasing tremendously to facilitate and establish a link between the physical world and information system....  相似文献   
52.
Optimization and Engineering - Aircraft ejection systems are lifesaving devices used, in case of emergencies for military pilots. As per current literature the success rate of ejections happening...  相似文献   
53.
Food Science and Biotechnology - The physico-chemical, polyphenols, antioxidant and antibacterial properties of berries and mixture of male and female leaves of Hippophae salicifolia were...  相似文献   
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The electrochemical discharge machining is a highly stochastic process involving a number of complex parameters. Controlling of these process parameters simultaneously to fetch the best possible performance is a difficult task. Determining an optimal parametric combination has become complex owing to interdependency of the parameters. In this work, the authors have made an attempt to establish the optimal combination of control parameters for machining of micro-channels on quartz glass. Taguchi’s standard orthogonal array (L 9) with Grey relational analysis (GRA) approach was used to establish the optimal parametric conditions for reducing the Width overcut (WOC) of micro-channels and increasing the Material removal rate (MRR). In order to optimize MRR and WOC together, the optimal combination of the selected control variables was obtained using the GRA. The experimental results showed the effectiveness of the adapted method to indicate the performance of the electrochemical discharge machining process.

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The design of Cellular Manufacturing Systems (CMS) has attained the significant attention of academicians and practitioners over the last three decades. Minimizing intercellular movements while maximizing utilization of machines are the main objectives of interest in designing CMS and are considered in present research. In this paper, the drawbacks of former neural networks-based approaches to cell formation are discussed. The standard version of cell formation problem is formulated and a 'Transiently Chaotic Neural Network' (TCNN) with supplementary procedures is introduced as a powerful rival. A simplified network is constructed. After developing the related equations the approach is tested using the proposed algorithm with 18 problems selected from literature. The results are compared with various other approaches including ART1, Extended-ART1, Ortho-Synapse Hopfield Neural Network (OSHN), etc. The main advantages of our proposed method are: (1) the ability to avoid the local optima trap, (2) the ability to solve problems of different sizes with the same set of values for parameters, and (3) the less computation time. The results also indicate considerable improvement in grouping efficiency through the proposed approach.  相似文献   
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BACKGROUND: The constructed soil filter (CSF), also known as soil biotechnology is a system for water renovation, which makes use of formulated media, culture of soil micro‐ and macro‐organisms, additives and plantation to purify water and wastewater. The process gives benefits in terms of applicability across very small to large scale, natural aeration, absence of moving parts, no biological sludge generation, odor free green aesthetic ambience. RESULTS: Residence time distribution (RTD) studies were carried out using laboratory scale CSF. Pulse potassium bromide tracer tests were carried out to determine RTD, and the Peclet number found to be 9–13 for a 2 m bed, and 2–3 for a 0.30 m bed with oxygen transfer of 0.08 h?1. CONCLUSION: The two‐channel dispersion model for flow behavior shows a good fit to the experimental data, indicating a reactor Peclet number 9–13 for a 2 m bed and 2–3 for a 0.3m bed. Oxygen transfer studies carried out using various methods gave an oxygen transfer coefficient of about 0.08 h?1. Wastewater purification studies indicate overall COD removal rate of around 50 mg L?1 h?1, suggesting that highly aerobic conditions are prevalent in the CSF system. Copyright © 2009 Society of Chemical Industry  相似文献   
59.
The direct α‐Csp2 H functionalization and thiomethylation of α‐oxoketene dithioacetals (DTAs) has been accomplished with dimethyl sulfoxide (DMSO) in the presence of iodine and a copper(I) salt for the first time. A prerequisite is the in situ iodination of the α‐Csp2 atom of dithioacetals that could offer other reaction channels. The operationally simple one‐pot protocol includes region‐defined consecutive iodination and sulfenylation of the challenging α‐Csp2 H bond of dithioacetals employing cheap and readily available reagents. DMSO here plays a dual role as thiomethyl source and solvent.

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This paper proposes a new measurement‐based approach that can solve synthesis problems in unknown linear circuits. The method makes use of a small number of measurements to determine the functional dependency of any circuit signal or variable on any set of design variables. Once the functional dependency is obtained, the design requirements can be applied to find the design parameter values. The results are described for linear direct current and alternating current circuits. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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