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141.
The article analyzes the influence of the Internet Protocol (IP) access interface on the packet loss probability and delay
times in the optical packet switched network. The network and node model have been proposed, and the structure of the IP access
interface, including assembler and holder, have been included in the analysis. It has been shown that the increase of the
maximum optical packet sizes, as well as use of the holding feature as contention resolution mechanism, decrease the packet
loss probability, but introduce delays at the optical network access points. Modeling and analysis were based on the discrete
event simulation assuming self-similar traffic sources. IP packet lengths were modeled using empirical data.
This work has been conducted while the author was affiliated with the Telecommunication Laboratory, Swiss Federal Institute
of Technology (EPFL-STI-ITOP-TCOM), Lausanne, Switzerland 相似文献
142.
143.
化学模式识别法在钢铁工业中的若干应用 总被引:1,自引:0,他引:1
本文涉及一种崭新的非函数数据处理法及其在工业诊断和优化中的应用。并对其进行要因分析和优化决策的原理作了介绍。结合钢铁工业生产中的实例进行了分析。还探讨了该方法在钢铁工业中应用的意义。 相似文献
144.
Gerardo Gabriel Acosta Miguel Angel Mayosky José Maria Catalfo 《Applied Intelligence》1994,4(1):53-66
This article proposes a scheme for the on-line adjustment of three mode controller settings based on experimental measurements of closed-loop performance. It uses a recently developed heuristic tuning procedure to identify estimated process parameters. This method may give rise to conflicting estimates. Fuzzy Set theory is applied to manage the situation in terms of a fuzzy conjunction to combine the various estimates. PID control was chosen because of its wide use in the industrial environment due to driving simplicity and robustness. The article shows design, development, and computer simulation aspects. 相似文献
145.
在假设交通很拥挤同时交通的转换率与路径费用成正比的前提下,构建了一个动态的转换率模型.为了获取转换率系统的全局渐近稳定,提出了一个普遍适用的Lyapunov函数方法,与此同时通过线性矩阵不等式方法,得到了保证转换率系统全局渐近稳定的充分条件. 相似文献
146.
Verbruggen Frederick; Liefooghe Baptist; Vandierendonck André; Demanet Jelle 《Canadian Metallurgical Quarterly》2007,33(2):342
In the task-switching literature, it has frequently been demonstrated that although advance task preparation reduces the switch cost, it never really eliminates the switch cost. This remaining residual switch cost received much attention, and it has been argued that advance preparation is restricted in nature. In the present study, the role of task-cue presentation in the establishment of the residual switch cost was investigated. In 4 experiments, the cue was removed during the preparation interval, and it was hypothesized that this would encourage participants to complete advance task preparation. The results of all 4 experiments provided support for this hypothesis: When the cue was presented for a short time and then removed, the residual switch cost completely disappeared. This was found for different cue types. Furthermore, Experiment 3 demonstrated that it was not the presence of the cue itself but merely differences in advance task preparation that caused the effects. This suggests that advance task preparation is not as restricted in nature as previously assumed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
147.
Manabu Ishitobi Takeshi Myoi Koji Soshin Eiji Hiraki Mutsuo Nakaoka 《Electrical Engineering in Japan》2005,153(3):79-87
This paper presents a single lossless inductive snubber‐assisted ZCS‐PFM series resonant DC‐DC power converter with a high‐frequency high‐voltage transformer link for industrial‐use high‐power magnetron drive. The current flowing through the active power switches rises gradually at a turned‐on transient state with the aid of a single lossless snubber inductor, and ZCS turn‐on commutation based on overlapping current can be achieved via the wide range pulse frequency modulation control scheme. The high‐frequency high‐voltage transformer primary side resonant current always becomes continuous operation mode, by electromagnetic loose coupling design of the high‐frequency high‐voltage transformer and the magnetizing inductance of the high‐frequency high‐voltage transformer. As a result, this high‐voltage power converter circuit for the magnetron can achieve a complete zero current soft switching under the condition of broad width gate voltage signals. Furthermore, this high‐voltage DC‐DC power converter circuit can regulate the output power from zero to full over audible frequency range via the two resonant frequency circuit design. Its operating performances are evaluated and discussed on the basis of the power loss analysis simulation and the experimental results from a practical point of view. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 153(3): 79–87, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20126 相似文献
148.
针对针织服装结构设计的特点和现状,运用东华原型的结构原理和技术应用方法,通过试样着装实验,进行比较分析,建立了针织服装基型,并阐述了其应用的方法. 相似文献
149.
R. S. Fyath K. N. Darraj M. S. Alam M. N. Islam M. M. Alkhatib 《Optical Memory & Neural Networks》2007,16(3):125-135
A new joint transform correlation (JTC) technique, named two-channel JTC (TJTC), is proposed in this paper for optical pattern
recognition applications. The TJTC technique independently evaluates the autocorrelation and crosscorrelation values of the
reference and the target images and employs a modified decision algorithm. In addition, optical threshold operation and fringe-adjusted
filter are incorporated in the proposed technique to enhance the correlation output and to improve the discrimination performance.
The proposed technique shows better recognition performance compared to existing JTC techniques. Computer simulation are presented
to investigate the salient features of the proposed TJTC technique with noise-free as well as noisy input scenes.
The text was submitted by the authors in English. 相似文献
150.
With the great advances of DWDM technology, optical cross-connects have to deal with much more wavelengths. Accordingly, the size of optical cross-connects become larger and larger; also the management cost is much higher. To simplify the architecture of cross-connects for low-complexity maintenance, waveband switching (WBS) in conjunction with several optical cross-connect architectures have been proposed and attracted much attention recently. The main concept of WBS is to group multiple wavelengths into a single waveband and what it concerns includes cross-connect cost and port count reduction. In this paper, we investigate the dynamic RWA problem (MG_DRWA) in WBS networks comprising of all-optical switches based on a cost-effective multi-granular optical cross-connect (MG-OXC) architecture. With this reconfigurable architecture, an optical cross-connect can switch at either fiber level, waveband level, or wavelength level according to its configuration. In order to effectively accommodate dynamic traffic demand, we propose a new MG_DRWA algorithm. Numerical results reveal that the proposed algorithm can achieve significantly better blocking performance as compared to a previously proposed algorithm named MILB under various traffic loads. 相似文献