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181.
182.
本文以综合医院交通系统与医院功能流线系统研究理论为基础,结合"医院街"设计理念,具体阐述医院交通系统与功能流线混乱问题的解决方案.  相似文献   
183.
The effect of time (1 and 4 h), pH (2.0 and 2.5) and temperature (80 and 90 °C) on yield and degree of esterification (DE) of durian rind pectin was investigated. The yield and DE of the extracted pectin ranged from 2.1 to 10.3% (w/w, based on dry weight of durian rind) and 45.6–64.8% respectively. Yield was significantly affected by time, temperature and pH, and interactions between temperature and pH, and heating time and pH. DE was significantly affected by heating time and pH, and interactive effects of temperature and pH, and heating time and pH. The extraction yield was not related to DE. By considering pectin yield and DE, the acid extraction of durian rind pectin at 80 °C, for 4 h and at pH 2.5 could be suitable.  相似文献   
184.
In this investigation we propose and demonstrate a wavelength widely tunable laser source employing a self-injected Fabry–Perot laser diode (FP-LD) for long-reach wavelength-division-multiplexed passive optical network (WDM-PON). By using a tunable bandpass filter and an optical circulator inside the gain cavity, a stable and single-longitudinal-mode (SLM) laser output is achieved. Besides, the proposed laser sources are directly modulated at 2.5 Gb/s for both downlink and uplink transmissions of 85 km single mode fiber (SMF) in PON without dispersion compensation.  相似文献   
185.
186.
本文对变腔深双层微穿孔板消声器进行了研究,提出了一种新的设计方法:即根据吸声系数最大原理选定双层微穿孔板消声器的腔深值。这种方法拓宽了消声器的消声频带宽度,改善了消声器的消声性能。这种设计方法已经实践检验,取得了良好的效果,从而证明这种方法是可行的。同时,本文还对双层傲穿孔板消声器的失效频率进行了讨论。  相似文献   
187.
生丝纤度连续性与纤度偏差关系的研究   总被引:1,自引:0,他引:1  
通过开发出利用自回归预测模型模拟生丝纤度时间序列的方法及计算机程序,就生丝纤度检测丝长从450m改为500m后纤度偏差值的换算问题,探讨了生丝纤度连续性对纤度偏差的影响。  相似文献   
188.
在假设各丝绞纤度期望值和丝绞内纤度均服从正态分布的条件下,导出分组抽样样本方差及均方差的方差计算式,并给出相应的等效样本容量,使偏差的分组抽检分级问题通过随机抽检分级理论得到解决。本文还阐明了绞间偏差对检验结果的影响及抽检方案的评价等基本问题。有关理论结果通过电算模拟试验得到验证。  相似文献   
189.
In the past, the selection of resources to execute various warehouse operation services was done solely by experts. In this paper, a RFID-based Resource Management System (RFID-RMS) is designed to help users to select the most suitable resource usage packages for handling warehouse operation orders by retrieving and analysing useful knowledge from a case-based data warehouse for solutions in both time saving and cost effective manner. In addition, a pure integral-linear programming model using a branch and bound algorithm to define the optimum travel distance of forklifts is also developed and embedded in the proposed system. The proposed system, which is suitable for usage in a warehouse operation environment, enhances the effectiveness in formulating resource usage package and managing resource operation by integrating the Radio Frequency Identification (RFID), case-based reasoning (CBR) technologies and the programming model for forklift route optimization. Through applying RFID-RMS in the GENCO Distribution System, a multinational logistics company, the utilization of warehouse resources is expected to be maximized while work efficiency will be greatly enhanced.  相似文献   
190.
In nowadays World Wide Web topology, it is not difficult to find the presence of proxy servers. They reduce network traffic through the cut down of repetitive information. However, traditional proxy server does not support multimedia streaming. One of the reasons is that general scheduling strategy adopted by most of the traditional proxy servers does not provide real-time support to multimedia services. Based on the concept of contractual scheduling, we have developed a proxy server that supports real-time multimedia applications. Moreover, we developed the group scheduling mechanism to enable processing power transfer between tasks that can hardly be achieved by traditional schedulers. They result in a substantially improved performance particularly when both time-constrained and non-time-constrained processes coexist within the proxy server. In this paper, the design and implementation of this proxy server and the proposed scheduler are detailed. Wai-Kong Cheuk received the B.Eng. (Hons.) and M. Phil. degrees in 1996 and 2001, respectively, from the Hong Kong Polytechnic University, where he is currently pursuing the Ph.D. degree. His main research interests include distributed operating systems and video streaming. Tai-Chiu Hsung (M'93) received the B.Eng. (Hons.) and Ph.D. degrees in electronic and information engineering in 1993 and 1998, respectively, from the Hong Kong Polytechnic University, Hong Kong. In 1999, he joined the Hong Kong Polytechnic University as a Research Fellow. His research interests include wavelet theory and applications, tomography, and fast algorithms. Dr. Hsung is also a member of IEE. Daniel Pak-Kong Lun (M'91) received his B.Sc. (Hons.) degree from the University of Essex, Essex, U.K., and the Ph.D. degree from the Hong Kong Polytechnic University, Hung Hom, Hong Kong, in 1988 and 1991, respectively. He is currently an Associate Professor and the Associate Head of the Department of Electronic and Information Engineering, the Hong Kong Polytechnic University. His research interests include digital signal processing, wavelets, multimedia technology, and Internet technology. Dr. Lun was the Secretary, Treasurer, Vice-Chairman, and Chairman of the IEEE Hong Kong Chapter of Signal Processing in 1994, 1995–1996, 1997–1998, 1999–2000, respectively. He was the Finance Chair of 2003 IEEE International Conference on Acoustics, Speech and Signal Processing, held in Hong Kong, in April 2003. He is a Chartered Engineer and a Corporate member of the IEE.  相似文献   
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