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991.
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Yiqiang Jiang Yang Yao Shiming Deng Zuiliang Ma 《International Journal of Refrigeration》2004,27(4):5061
Grey forecasting has found applications in finance, social science, economics, etc. However, its applications in air conditioning and refrigeration have not been reported. This paper reports on a study where grey forecasting method is applied to predicting the operating energy performance for an air cooled water chiller (ACWC) units, so as to demonstrate this forecasting approach can be applied to building Heating Ventilation and Air Conditioning (HVAC) installations. In this paper, a brief introduction of the background and fundamentals of grey forecasting is firstly presented. This is followed by reporting the application of grey forecasting to an ACWC unit installed in Northern China for predicting its operating energy performance using the variation ratio of coefficient of performance (ΔCOP). The predicted values of ΔCOP agreed well with the measured ΔCOP, demonstrating that grey forecasting may be used for predicting the operating energy performance of an ACWC unit with a high accuracy. Finally, the potential use of grey forecasting in fault detection and diagnostics (FDD) or energy management systems (EMSs) for air conditioning and refrigeration systems is assessed, and the comparison with the prediction method based on artificial neural network (ANN) discussed. 相似文献
995.
提高第三方物流企业服务水平的对策 总被引:8,自引:0,他引:8
要促进第三方物流企业的发展,提高第三方物流企业的竞争力,使其具有参与国内外竞争能力,就必须提高其服务水平,使其与国际水平接轨。笔者分析了目前我国第三方物流企业的服务现状,并提出改进第三方物流企业服务水平的建议。 相似文献
996.
Lixin Ma Changmei Cheng Xiaohong Liu Yufen Zhao Anlin Wang Piet Herdewijn 《Chemometrics and Intelligent Laboratory Systems》2004,70(2):123-128
A back propagation (BP) neural network (NN) method has been developed to predict the stability of RNA/DNA duplex. Calculated Tm of hybrid formation with the present parameters fits the experimental values within reasonable errors (AD=1.2887 K, SEP=1.782, R2=0.9673 for NN1; AD=2.1388 K, SEP=3.506, R2=0.8889 for NN2). And it has the advantage that the determinations of thermodynamic parameters (TP) are not needed. 相似文献
997.
A comparative study of research performance in computer science 总被引:4,自引:5,他引:4
The paper compares the research performance in computer science of four major Western countries, India and China, based on
the data abstracted from INSPEC database during the period 1993–2002. A total of 9,632 computer science papers recorded in
INSPEC database were used for the comparison. The findings indicate that, on the one hand, the number of papers produced in
China has considerably increased in the past few years. Particularly, in recent years, China occupies a remarkable high position
in terms of counts of papers indexed by the INSPEC database. On the other hand, Chinese scientists preferred to publish in
domestic journals and proceedings and shares of SCI-papers to the total journal papers for China have still remained the lowest.
This indicates that the research activities of Chinese scientists in computer science are still rather “local” and suffer
from a low international visibility. Various scientometric indicators, such as Normalized Impact Factor, ratio of papers in
high quality journals are further adopted to analyze research performance and diverse finding are obtained. Nevertheless,
for these surrogate indicators, China has optimistically achieved great progress, characterized with “low level of beginning
and high speed of developing”. The policy implication of the findings lies in that China, as well as other less developed
countries in science, can earn relative competitive advantages in some new emerging or younger disciplines such as computer
science by properly using catch-up strategy.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
998.
本文介绍了一种以NI公司的PCI-6024E为基础,基于虚拟仪器的飞行体姿态测试系统,该系统可实现7路信号的同步采集,可将信号保存为三种格式的文件,方便进行后续数据分析处理和仿真. 相似文献
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1000.
结合实例说明,搞好清洁生产对氯化法钛白企业治理环境污染,提高企业的经济效益和今后长远发展起着举足轻重的作用和重要的指导意义. 相似文献