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81.
交通信号模糊控制方法研究 总被引:7,自引:0,他引:7
席晓慧 《微电子学与计算机》2004,21(8):30-32
文章通过分析十字路口交通堵塞的原因。提出了使在十字路口排队车辆最少的交通信号灯模糊控制方法。文中给出了模糊控制量的选取、模糊控制规则的定义和解模糊的方法,以及模糊控制的原理图。以十字路口排队车辆的数量和车辆的等待时间作为模糊输入,可以有效地使车辆在十字路口的等待时间最短、堵塞车辆最少。 相似文献
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83.
李静雅 《电气电子教学学报》2020,(1):163-166
为更好的提高实验教学效果,将微课引入“电路与模拟电子技术”实验教学,将实验仪器操作、实验涉及理论、仿真实验、拓展实验等多方面实验内容录制成微课,辅助学生学习、完成实验,解决传统实验教学课时少,内容多、实验模式固定、实验结果单一等问题,帮助提高学生实践应用能力。 相似文献
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自动化专业大类系列课程建设是对该专业课程体系的整体建设。本文对自动化专业大类课程的课程体系、实验体系、实践教学等方面做了详细的阐述。大类系列课程的建设,将保证本科课程体系结构的相对稳定,为培养方案的制定和各类人才的培养提供了保障。 相似文献
86.
建筑行业发展中计算机的使用范围在日益增大,我国的计算机技术也朝着网络化和智能化、多媒体化发展模式逐步前行,建筑时大小、材料等问题是必须要考虑的因素,同时要满足建筑集美学、绘画和雕塑为一体新要求,以上诸多要求通过计算技术的应用都能得以实现,本文主要介绍计算机应用的必要性和技术使用要点,为建筑设计的稳步发展提供新的借鉴和参考. 相似文献
87.
目前网络教学的推行,是适应教学改革的发展。网络课程为其提供最基础的教学环境。本文基于会计电算化的课程设计,推行网络教学平台,体现过程管理,约束学生进行学习,最终使得学生能有快又好的掌握会计电算化的基本知识。 相似文献
88.
Mohamadreza Marandian Hagh Masoud Salehi Abhay Sharma Zoran Zvonar 《Wireless Personal Communications》2006,39(2):165-182
In the Frequency Division Duplex (FDD) mode of the Third Generation Partnership Project (3GPP) standard, implementation of the turbo decoder, especially for the mobile equipments, faces design decisions related to computational complexity, power efficiency, and memory requirements. In this paper we compare different approaches of low complexity implementation of the turbo decoder, with emphasis on the issues of signal scaling and quantization, the sliding window operation for memory size reduction and the iteration stopping algorithms. The demodulated signal at the output of the RAKE receiver may have a wide dynamic range and it may require many bits of precision. In order to overcome the numerical precision problem and to prevent Log Likelihood ratio (LLR) metric overflow, a scaling algorithm must be used. Our simulation results indicate that the Average Absolute (AA) algorithm using dynamic scaling outperforms other scaling schemes and it is less sensitive to the channel conditions. One of the major challenges in the implementation of a practical turbo decoder is optimization of memory requirements. In this paper we evaluate the performance of the sliding window algorithm using different main and guard window sizes. We show that the bit and block error rate performance of the sliding window scheme mainly depend on the guard window size rather than the main window size. The simulation results indicate that small guard window sizes can significantly decrease the iteration gain for large frames in fast fading channels. Iteration stopping algorithms reduce the power consumption and the latency of the decoder and help to dedicate more resources to other functions of the receiver. The block error distribution in the fading channels makes it even more essential to use an iteration stopping rule. Our simulations conclude that a rule called the minimum absolute value appears to be a very effective, low complexity and robust algorithm.
Mohamadreza Marandian Hagh was born in Tabriz, Iran on January 1974. He received the B.S. and the M.S. degrees in electrical engineering from Tehran University with honors in 1996 and 1999, respectively. He is pursuing the Ph.D. degree in electrical engineering at Northeastern University, Boston. His research interests includes information theory, channel coding and iterative techniques for wireless communication systems. His current research is focused on low complexity designs for iterative receivers using Space-Time coding in time-dispersive channels. He is also interested in Exit-Chart analysis of iterative receivers. From 1996 to 1999, he was with Sana Pro Inc. as a system engineer, developing simulation tools for OFDM, WCDMA, CDMA2000. He is currently with Airvana Inc. in Chelmsford, MA and working on 1xEVDO wireless systems.
Masoud Salehi received BS degree (Summa Cum Laude) from Tehran University and MS and Ph.D. degrees from Stanford University all in Electrical Engineering. Before joining Northeastern, he was with the Departments of Electrical and Computer Engineering, Isfahan University of Technology and Tehran University. From February 1988 to May 1989 Dr. Salehi was a visiting professor at the Information Theory Research Group, Department of Electrical Engineering, Eindhoven University of Technology, The Netherlands, where he did research in network information theory and coding for storage media.In 1989 Dr. Salehi joined Department of Electrical and Computer Engineering, Northeastern University. Professor Salehi is a member of the CDSP (Communication and Digital Signal Processing) Center. His main areas of research interest are network information theory, source-channel matching problems in single and multiple user systems, data compression, turbo coding, coding for fading channels, and digital watermarking. Professor Salehi’s research has been supported by research grants from the National Science Foundation (NSF), GTE, NUWC, CenSSIS, and Analog Devices. Professor Salehi has also done consulting to the industry including Teleco Oilfield Services and AT&T. Professor Salehi is currently a member of the Editorial Board of The International Journal of Electronics and Communications.Professor Salehi is the coauthor of the textbooks “Communication Systems Engineering”, Prentice-Hall 1994, 2002, “Contemporary Communication Systems Using MATLAB and Simulink” Thomson 1998, 2000, 2004, and “Fundamentals of Communication Systems”, Prentice-Hall 2005.
Abhay Sharma received B.E. (Hons) Electrical and Electronics Engineering degree from Birla Institute of Technology and Science, Pilani, India in 1996 and M.S. Electrical Engineering degree from Ohio State University, Columbus in 2000. From 2000 to 2005 he was working with Analog Devices, RF and Wireless Systems Group, Wilmington, USA, where he was working on design and implementation of algorithms for the emerging cellular communication standards. Currently he is working with Allgo Embedded Systems, Bangalore, India, in the area of wireless networks and systems based on the emerging W-PAN wireless technologies.
Zoran Zvonar received the Dipl. Ing. degree in 1986 and the M.S. degree in 1989, both from the Department of Electrical Engineering, University of Belgrade, Yugoslavia, and the Ph.D. degree in Electrical Engineering from the Northeastern University, Boston, in 1993.From 1986 to 1989 he was with the Department of Electrical Engineering, University of Belgrade, Belgrade, Yugoslavia, where he conducted research in the area of telecommunications. 1993 to 1994 he was a Post-Doctoral investigator at the Woods Hole Oceanographic Institution, Woods Hole, MA, anconducted research on multiple-access communications for underwater acoustic networks. Since 1994 he has been with the Analog Devices, Communications Division, Wilmington, USA. He is the Manager of the Systems Engineering Group focusing on the design of algorithms and architectures for wireless communications, with emphasis on integrated solutions and real-time software.He was a Guest Editor of the IEEE Transactions on Vehicular Technology, the International Journal of Wireless Information Networks and the ACM/Baltzer Wireless Networks, Associate Editor of the IEEE Communications Letters and a co-editor of the books GSM: Evolution Towards Third Generation Systems, Kluwer Academic Publishers, 1998, Wireless Multimedia Networks Technologies, Kluwer Academic Publishers, 1999 and Software Radio Technologies: Selected Reading, IEEE Press, 2001. Dr. Zvonar is currently Co-Editor of the Radio Communication Series in the IEEE Communications Magazine. 相似文献
89.
协同项目多目标任务分配优化算法 总被引:2,自引:0,他引:2
在协同项目中,伙伴企业间的任务分配问题直接影响到项目的整体获益。针对这一问题,以费用最小和承担企业数最少为目标,并充分考虑了任务之间的紧密关联关系,提出了一个有效的任务分配启发式算法,并进行了实例验证,给出了对算法的评价。 相似文献
90.
从永登县网络建设存在的问题出发,通过对几种建网模式的分析比较,认为无线数字传输具有很大优势,并根据当地实际情况,提出永登县农村网络建设的无线数字接入规划方案。 相似文献