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Increasing environmental awareness and stringent environmental regulations have motivated many companies to incorporate ecodesign into product development.To assist companies to address the challenge,this research presents a design for environment(DfE) methodology to evaluate and improve derivative consumer electronic product development using a back-propagation neural network(BPNN) model and a technique for order preference by similarity to ideal solution(TOPSIS) method.Based on use of a BPNN,the life cycle assessment(LCA) models are developed to estimate quantities of hazardous chemical substances and energy consumption for a derivative consumer electronic product throughout the product life cycle.A performance evaluation and improvement model for DfE is then devised based on the TOPSIS method to analyze the ecodesign performance and provide concrete improvement strategies.With the aforementioned analysis of environmental performance,an enterprise can profoundly understand and significantly enhance the relative DfE performance of a new product compared to the similar competitive products.Finally,we apply an optical mouse development project as a case to elaborate and demonstrate the effectiveness of the proposed methodology.These analytical results can let us understand the DfE performance ranking and acquire the maximum reduced quantity of each DfE criterion for each module of a new product.Meanwhile,to enhance the green competitiveness of the new product,we recommend that the engineers should decrease the area of the circuit board of the new product.In addition,the material of the USB cable for the new product should be switched from the PVC material to the PE material. 相似文献
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In the empirical literature, it has been shown that there exists both linear and non‐linear bi‐directional causality between trading volumes and return volatility (measured by the square of daily return). We re‐examine this claim by using realized volatility as an estimator of the unobserved volatility, adopting a stationary de‐trended trading volume, and applying a more recent data sample with robustness tests over time. Our linear Granger causality test shows that there is no causal linear relation running from volume to volatility, but there exists an ambiguous causality for the reverse direction. In contrast, we find strong bi‐directional non‐linear Granger causality between these two variables. On the basis of the non‐linear forecasting modeling technique, this study provides strong evidence to support the sequential information hypothesis and demonstrates that it is useful to use lagged values of trading volume to predict return volatility. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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R. G. Chiang J. A. Chiang K. G. Davey 《Cellular and molecular life sciences : CMLS》1992,48(11-12):1122-1125
The dorsal vessel of the blood feeding insect,Rhodnius prolixus, was found to increase or decrease its rate of contraction in response to a number of different stimuli. Handling increased contraction rates whereas tactile stimulation of the ventral abdominal cuticle inhibited contraction. Injection of very low concentrations of serotonin or of high concentrations of octopamine enhanced the inhibitory effect, apparently by acting via the nervous system. Higher concentrations of serotonin increased heart rate by acting directly on the myocardium. The inhibitory response is suggested to be one facet of a generalised thigmotactic response. 相似文献
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Multiple phosphoglucomutase (E.C.2.7.5.1) alleles are found in the mosquitoes Mansonia crassipes and M. uniformis. The present study reveals 4 Pgm alleles, of which Pgm(B) and Pgm(C) are common to both species while Pgm(A) is present only in M. crassipes and Pgm(D) only in M uniformis. The frequencies in both species accord well with Hardy-Weinberg expectations. The most frequent allele is that controlling a phenotype with an intermediate electrophoretic mobility, viz Pgm(B) in M. crassipes and Pgm(C) in M. Uniformis. 相似文献
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Suppression of lung adenocarcinoma progression by Nkx2-1 总被引:1,自引:0,他引:1
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随着科学技术的不断发展,以互联网技术、数字技术及移动通讯技术为核心的新媒体在高校得到了广泛传播和应用,如何积极应对新媒体带来的影响,是辅导员做好大学生思想政治教育工作的基本要求。本文对新媒体特点进行了分析,并就高校辅导员如何发挥新媒体作用,创新大学生思想政治教育载体提出建议。 相似文献