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A 16PSK-OFDM-FSO Communication System under Complex Weather Conditions

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Optics and Photonics Journal 2016年第8期6卷 131-135页

作者： Junyi Zhou Yufeng Shao zhifeng wang Changxiang Li Yue Zhou Wenzhe Ma Faculty of Engineering Shanghai Polytechnic University Shanghai China

Free Space Optical (FSO) communication is one of the most promising access methods. But, the different weather conditions will affect the transceiver performance. In this paper, we build a FSO communication system with 16-ary phase shift key-orthogonal frequency division multiplexing (16PSK-OFDM) downstream signals. We analyze the transmission performance of 16PSK-OFDM optical signals under five different weather conditions (sunny, light rain, moderate rain, snow, and fog). The optical spectral diagrams, constellation diagrams, and bit error rate (BER) of the received signals are simulation measured and analyzed. The results show that the constellation diagram under sunny condition is clear, and the value of BER is about 10?4.2 after 16PSK-OFDM optical signals pass through 500 m FSO link. Note that, the constellation points are dispersed under the other weather conditions.

关键词： Optical Communication OFDM FSO BER Constellation Diagram

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塔式电站定日镜场布置范围的理论分析

太阳能学报 2011年第1期32卷 89-94页

作者：张宏丽王志峰中国科学院电工研究所北京100190 沈阳工程学院沈阳110136

采用MALAB编程,计算了余弦效率、大气透过效率以及吸热器开口平面上的截断效率,并将这三项效率的乘积定义为地面利用效率用于限制定日镜场的布置范围,进而分析了一些参数对定日镜场布置范围的影响。分析结果表明,地面利用效率可有效限... 详细信息

采用MALAB编程,计算了余弦效率、大气透过效率以及吸热器开口平面上的截断效率,并将这三项效率的乘积定义为地面利用效率用于限制定日镜场的布置范围,进而分析了一些参数对定日镜场布置范围的影响。分析结果表明,地面利用效率可有效限定定日镜场的布置范围。与接收塔光学高度和吸热器开口的倾斜角度相比,吸热器的开口尺寸和定日镜的整体误差大小在很大程度上限定了定日镜场的布置范围。要增大电站容量,必须增大吸热器开口尺寸。而提高定日镜的整体性能不但可提高定日镜场的光学效率,也可有效扩大定日镜场的布置范围,增大电站容量。

关键词：塔式电站定日镜场余弦效率大气透过效率截断效率误差

Research on Dispersion Compensation of 40 GB/s Optical Duo-Binary Coded Transmission System

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Optics and Photonics Journal 2016年第8期6卷 190-195页

作者： Yue Zhou Yufeng Shao zhifeng wang Changxiang Li Junyi Zhou Wenzhe Ma Faculty of Engineering Shanghai Polytechnic University Shanghai China

A 40 Gb/s high speed optical transmission system is designed, and the different dispersion compensation schemes are adopted to realize the transmission of the optical duo-binary (ODB) signals over 120 km optical fiber. Optical duo-binary signals are generated by using a precoder, two low- pass filters (LPF) and one mach-zehnder modulator (MZM). Through combination of dispersion compensation fiber (DCF) and single mode fiber (SMF) in the transmission link, four different dispersion compensation schemes (pre-compensation, post-compensation and hybrid compensation (pre+ post) and hybrid compensation (post+ pre)) were compared. Analyzing Q factor, BER, eye diagrams and receiver sensitivity in several dispersion compensation schemes, the simulation results are: the cut-off frequency of LPF affects the transmission performance, and the hybrid compensation (post+ pre) scheme is the optimal dispersion compensation method.

关键词： Optical Communication Duo-Binary Dispersion Compensation Q Factor Eye Diagrams

Optical 64QAM-OFDM Transmission Systems with Different Sub-Carriers

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Optics and Photonics Journal 2016年第8期6卷 196-200页

作者： Changxiang Li Yufeng Shao zhifeng wang Junyi Zhou Yue Zhou Wenzhe Ma Faculty of Engineering Shanghai Polytechnic University Shanghai China

In this paper, the transceiver performance of optical 64QAM-OFDM signals with different sub-car- riers is studied. Firstly, we build a 40Gbit/s optical coherent 64QAM-OFDM transmission system. 64QAM-OFDM optical signals with 16, 32, 64, 64, 128, 256 and 512 sub-carriers are transmitted over 100 km single mode fiber (SMF). Then, the optical spectrum diagrams before and after transmission, the bit error rate (BER) and constellation diagrams of received signals were compared. The simulation results show that, with the number of sub-carriers increasing, the value of PAPR will gradually increase and the quality of the received optical signals will deteriorate. Moreover, with the number of sub-carriers increasing, the computational complexity will increase when digital signal processing (DSP) is used. Therefore, we should choose the optimal number of sub-carriers, and the PAPR influence and BER are also considered for achieving effective transmission.

关键词： Optical Fiber Communications OFDM Computational Complexity PAPR BER

考虑地形影响和多点激励的大跨高墩桥地震响应分析

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土木工程学报 2006年第1期39卷 50-53,59页

作者：王蕾赵成刚王智峰北京交通大学路桥集团桥梁技术有限公司北京100102

提出一种综合考虑行波和地形影响的大跨结构在多点输入下的地震响应分析方法。首先计算P波在多种角度入射下两座山峰以及其间自由场地的时程响应,并以此作为两座山峰之间大跨桥梁的桥台及桥墩基础多支承点处的地震输入,这种地震输入综... 详细信息

提出一种综合考虑行波和地形影响的大跨结构在多点输入下的地震响应分析方法。首先计算P波在多种角度入射下两座山峰以及其间自由场地的时程响应,并以此作为两座山峰之间大跨桥梁的桥台及桥墩基础多支承点处的地震输入,这种地震输入综合了行波和地形的影响。然后基于多点激励下地震响应分析方法,编制有限元分析程序,在此基础上分析了考虑行波和地形综合影响下一座360m4跨高墩连续刚构桥的多点激励地震响应。从分析结果看,考虑地形效应和不考虑地形效应的差别较大,不考虑地形效应可能会较小的估计结构的内力响应。因此,大跨度结构地震响应分析应考虑地形的影响。本文分析结果可供抗震设计参考。

关键词：地形效应多点激励大跨高墩桥行波效应

Online Supervision of Penicillin Cultivations Based on Rolling MPCA

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Chinese Journal of Chemical Engineering 2007年第1期15卷 92-96页

作者：汪志锋袁景淇 Department of Automatic Control Shanghai Jiao Tong University Shanghai 200030 China Department of AutomationShanghai Second Polytechnic University Shanghai 201209 China Department of Automatic Control Shanghai Jiao Tong University Shanghai 200030 China State Key Laboratory of Bioreactor Engineering East China University of Science & Technology Shanghai 200237 China

To reduce the variations of the production process in penicillin cultivations, a rolling multivariate statis-tical approach based on multiway principle component analysis (MPCA) is developed and used for fault diagnosis of penicillin cultivations. Using the moving data windows technique, the static MPCA is extended for use in dy-namic process performance monitoring. The control chart is set up using the historical data collected from the past successful batches, thereby resulting in simplification of monitoring charts, easy tracking of the progress in each batch run, and monitoring the occurrence of the observable upsets. Data from the commercial-scale penicillin fer-mentation process are used to develop the rolling model. Using this method, faults are detected in real time and the corresponding measurements of these faults are directly made through inspection of a few simple plots (t-chart, SPE-chart, and T2-chart). Thus, the present methodology allows the process operator to actively monitor the data from several cultivations simultaneously.

关键词： multiway principle component analysis fermentation online supervision fault diagnosis rolling

人力资本参与收入分配:高校教师收入分配制度创新研究

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国家教育行政学院学报 2009年第8期140卷 41-44页

作者：王志丰闽江学院福建福州350108

人力资本是高校教师从事价值创造的重要要素,是脑力劳动的重要组成部分。人力资本参与收入分配是高教领域按劳分配和按生产要素分配相结合的关键。高校人力资本参与收入分配具有现实可行性。

关键词：高校教师人力资本收入分配

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区域经济一体化中的治理机制创新

天津社会科学 2006年第3期 67-70页

作者：王志锋清华大学公共管理学院

一、“多层次分割”：区域经济一体化之难

关键词：区域经济一体化机制创新城市化进程治理沿海发达地区中国经济发展地域限制长江三角洲珠江三角洲城市密集区

PAPR Influence Analysis in 8QAM-OFDM Optical Access Systems

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Optics and Photonics Journal 2016年第8期6卷 127-130页

作者： Wenzhe Ma Yufeng Shao zhifeng wang Changxiang Li Yue Zhou Junyi Zhou Faculty of Engineering Shanghai Polytechnic University Shanghai China

In this article, the peak to average power ratio (PAPR) performance of 8 quadrature amplitude modulation-orthogonal frequency division multiplexing (8QAM-OFDM) optical signals has been researched in broadband optical access system. The complementary cumulative distribution functions (CCDFs) are analyzed of two different 8QAM-OFDMsignals with 16, 32, 64, 128, 256, 512 sub- carriers by simulation. The simulation results show that, with the increase of the number of subcarrier, the PAPR value becomes higher. When the numbers of subcarrier are16 and 512, the PAPR of 8QAM-OFDM optical signals are smaller than 5.2 dB and 5.3 dB respectively. Hence, the number of sub-carriers should be chosen according to practical application.

关键词： Optical Access System 8QAM-OFDM Sub-Carrier PAPR CCDF