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Overvoltage Suppression for UHV Transmission Lines

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Transactions of tianjin University 2008年第3期14卷 222-225页

作者：李永丽刘太华李仲青景雷龙英范建忠 Key Laboratory of Power System Simulation and Control of Ministry of Education Tianjin University ABB (china) Research ltd.

The overvoltage phenomena of ultra high voltage (UHV) transmission lines are analyzed and verified by EMTDC/PSCAD simulation. Referring to the theoretical analyses and operating experiences of extra high voltage (EHV) transmission lines in china and UHV transmission lines in Russia and Japan, the methods to suppress the internal overvoltage in UHV transmission lines by protection and control strategies are discussed. Through the cooperation among the recloser, shunt reactor, tripping and closing resistance, and metal oxide varistor(MOV), the overvoltage can be restrained within an acceptable level.

关键词： overvoltage reclosing relay protection shunt reactors suppression UHV transmission lines

EARLY PALAEOZOIC PRIMARY OIL OF KONGXI BURIED HILL IN HUANGHUA DEPRESSION, HUABEI, china

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石油勘探与开发 1997年第3期24卷 92-95页

作者： Wang Zhaoyun Cheng Keming(Research Institute of Petroleum Exploration and Development, CNPC, Beijing, 100083)Yang Chiyin(Geology and Development Institute, Dagang Oil Field Group ltd., tianjin, 300280)

Huabei area suffered a sedimentary interruption of about 130 million years during Late Ordovicianto Devonian period. Therefore, whether the Early Palaeozoic carbonate rocks with a stable distribution and alarge thickness can secondarily generate hydrocarbon and form Primary oil and gas Pool is an important issueregarding the prospecting for Primary oil and gas Pools in the Lower Palaeozoic formations. Well Konggu 3,located in the northwestern Kongdian anticlinal structural belt, produced oil from the Primary Ordovician limestoneoil pool reserved in the Ordovician Fengfpog Formation. The crude oil Characteristics and oil-source correlationshow that oil source rock are Ordovician limestone. So it is a primary oil pool with source and reservoir rads inthe same formation. The studies on the secondsry hydrocarbon generation of source rocks and the primary oil ofWell Konggu 3 have a great significance to firmly prospect for Lower Palaeozoic primary oil and gas pools inHuabei area.

关键词： Subject heading Early Palaeozoic Primary reservoir Oil-source correlation Huanghua depression Huabei area

Development of 340MPa Grade Galvanized Automotive HSLA Sheet of Shougang

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Journal of Iron and Steel Research International 2011年第S1期18卷 990-993页

作者： QI Chun-yu 1,LIN Li-bin 2,ZHOU Jian 2,LIU Guang-ming 2,YIN Xian-dong 1 (1.Beijing Shougang Cold Rolling company,ltd.,Beijing 101304,china 2.Shougang Research Institute of Technology,Beijing 100041,china) Beijing Shougang Cold Rolling Co ltd Beijing 101304 Peoples R China Shougang Res Inst Technol Beijing 100041 Peoples R China

In the paper,development of 340MPa galvanized grade HSLA sheet of Shougang is *** effects of annealing parameters on the precipitates,microstructures and mechanical properties were *** to the experiment,it was indicated that the fine microstructures and disperse carbide of Nb caused high strength of the *** now,the product has been used to the reinforced inner panel.

关键词： HSLA microstructure property precipitation galvanizing

Design of Submarine Pipeline in BZ34-2/4 Oil Field

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china Ocean Engineering 1992年第3期7卷 279-296页

作者： Wang Jinying Senior Engineer, Bohai Engineering and Design company, 300452 tianjin

This paper presents the detail design conditions, design criteria and methods as well as design conclusions of the process, structure and corrosion of the production flowlines and high pressure water injection lines in BZ34-2 / 4 oil field in Bohai Bay. At present this design represents the design capability and level in the field of the submarine pipeline engineering of china.

关键词： submarine pipeline slugging inhibitor riser inplace stability cathodic protection

Striding Forward Towards International Market

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china's Foreign Trade 2003年第1期 24-25页

作者： tianjin ZHONGXINPHARMACEUTICAL GROUP CO.,ltd.

As the first Chinese enterprise published S-stock in abroad, on May 1997,tianjin Zhongxin Pharmaceutical Group Corporation successfully published stocks in Singapore. On June 2001, the company published it’s A-stock in Shanghai Stock Exchange. For any pharmaceutical enterprises in china, Zhongxin company is the first one simultaneously owned S-stock and A-stock.

关键词： GMP in In up as is of have Striding Forward Towards International Market over for

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补偿电网增量函数法接地选线原理及应用

上海交通大学学报 2004年第8期38卷 1273-1277页

作者：蔡旭于乐中上海交通大学电气工程系上海200030 天津航博电气发展公司天津300192

深入分析了补偿电网单相经电阻接地的现象,利用消弧线圈支路阻抗变化前后的系统零序电压、第j支路零序电流及常态下不平衡电流,定义了零序电流增量函数的概念.建立了增量函数与消弧线圈支路阻抗变化前零序电压百分数和该支路电流变化量... 详细信息

深入分析了补偿电网单相经电阻接地的现象,利用消弧线圈支路阻抗变化前后的系统零序电压、第j支路零序电流及常态下不平衡电流,定义了零序电流增量函数的概念.建立了增量函数与消弧线圈支路阻抗变化前零序电压百分数和该支路电流变化量之间的关系.构建了零序电流增量函数法接地选线判据,该判据既可用于随动式补偿系统,又可用于预调式补偿系统.研制出基于上述原理的接地选线装置,给出了装置的硬件结构图及软件流程.经1年多的样机现场运行表明,该装置选线准确、可靠.

关键词：接地故障检测零序电流增量函数消弧线圈控制

Capacity analysis and optimal power allocation for coordinated transmission in MIMO-OFDM systems

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Science china(Information Sciences) 2012年第6期55卷 1372-1387页

作者： CUI QiMei 1,HUANG XueQing 1,LUO Bing 1,TAO XiaoFeng 1 & JIANG Jun 2 1 Key Laborary of Universal Wireless Communications,Beijing University of Posts and Telecommunications,Beijing 100876,china 2 StarPoint Communication Software company ltd.,Beijing 100102,china 1. Key Laborary of Universal Wireless Communications Beijing University of Posts and Telecommunications Beijing 100876 China2. StarPoint Communication Software Company Ltd. Beijing 100102 China

Coordinated transmission in multicell coordination networks has attracted much attentions in recent *** the paper,we investigate one open problem in the above area,which is concerned with how to solve the closed-form optimal power allocation scheme of coordinated transmission in downlink orthogonal frequency-division multiplexing (OFDM) systems with multiple antenna configurations and individual power constraints.A frequency-selective fading multiple-input multiple-output (MIMO) channel is *** derive the closed-form solutions of sum-rate capacity and optimal power allocations for coordinated transmission under the diversity case and the multiplexing case by solving the constrained optimization *** simulations are performed to verify the derived theoretical conclusions by means of comparing the proposed optimal power allocation (OPA) scheme with the other two typical power allocation *** is the power allocation scheme combining traditional water-filling with equal power (WS-EF PA).The other is equal power allocation (EPA) scheme.

关键词： coordinated multi-point transmission multicell cooperation capacity analysis MIMO-OFDM power allocation frequency selective MIMO channel

Features of the fault system and its relationship with migration and accumulation of hydrocarbon in Liaodong Bay

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Petroleum Science 2011年第3期8卷 251-263页

作者： Xu Guosheng Ma Ruolong Gong Deyu Zhou Donghong Li Jianping Guo Yonghua Yuan Haifeng Wu Changrong State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology Chengdu Sichuan 610059 China Exploration and Development Research Institute Tianjin Branch of CNOOC （China） Co. Ltd. Tanggu Tianjin 300452 China

The fault system of Liaodong Bay developed extensively under the control of the Tanlu Fault. The fault system can be grouped into strike-slip faults of grade Ⅰ, trunk faults of grade Ⅱand branch faults （induced faults） of grade Ⅲ respectively based on its developmental scale. The faults of grade Ⅰ and Ⅱwere deep, early and large while the faults of grade Ⅲwere shallow, late and small. The formation, evolution and distribution features played a significant role in controlling the migration of oil and gas in both horizontal and vertical directions. The fluid transfer in the fault system occurred in the process of faulting. The strike-slip and trunk faults moved actively forming predominant pathways for oil and gas migration. The branch faults, with weak activity, generally controlled the development of traps and were beneficial for the accumulation and preservation of oil and gas. The faults of grade Ⅰ and Ⅱ formed the major migration pathways for oil and gas, but their fault activity rates appeared to vary along their strikes. The zones with a relatively low fault activity rate might be favorable for oil and gas accumulation. When the activities of strike-slip, trunk, and branch faults came to a halt, the fault seal behavior had a vitally important effect on the accumulation of oil and gas. The controlling role of the fault over fluid distribution was further analyzed by calculating the fault activity quantitatively.

关键词： Liaodong Bay fault system fault activity rate fault seal behavior migration andaccumulation of oil and gas

Optimum Design for Offshore Platform Structural Reliability

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china Ocean Engineering 1992年第3期7卷 265-278页

作者： Zhu Qixian Senior Engineer, Bohai Engineering and Design company,300452 tianjin Bohai Engineering & Design company 300452 Tianjin China

In this paper, the main problems concerning reliability design of offshore platform structure are described and the general steps for the use of Safety Coefficient Method are presented.

关键词： offshore platform platform structure reliability analysis safety coefficient method optimum design