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浙江大学学报（工学版） 2013年第11期47卷 1917-1925页

作者：楼文娟杨伦陈勇阎东浙江大学结构工程研究所浙江杭州310058 河南电力试验研究院河南郑州450052

为了研究输电塔横担在覆冰导线作用下的受力变形特征,以在冰灾发生时横担严重破坏的某转角耐张塔为对象,按照模型相似理论制作大比例节段模型,进行模拟导线重覆冰状态下的静力加载试验.考虑连接偏心、节点板厚度和螺栓长度等因素对构件... 详细信息

为了研究输电塔横担在覆冰导线作用下的受力变形特征,以在冰灾发生时横担严重破坏的某转角耐张塔为对象,按照模型相似理论制作大比例节段模型,进行模拟导线重覆冰状态下的静力加载试验.考虑连接偏心、节点板厚度和螺栓长度等因素对构件传力路径的影响,建立中横担精细化有限元模型,对试验全程进行模拟并与试验对比.在此基础上通过非线性屈曲计算,获得覆冰导线静张力作用下横担的失效模式及薄弱位置.研究表明:横担主材两端螺栓分别连接在角钢的水平肢和竖直肢上会造成构件各个截面应力状态相差很大并使受压构件在局部位置产生受拉区域.对于斜材,连接偏心引起的弯矩和二阶效应不可忽略,且受压斜材是横担的薄弱环节,斜材稳定承载力的不足会导致横担的整体失效.

关键词：输电塔横担覆冰导线静力试验有限元模拟

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3.00 V高性能混合SiC模块研制

固体电子学研究与进展 2024年第1期44卷 13-18页

作者：刘艳宏杨晓菲王晓丽荆海燕刘爽中车永济电机有限公司西安710016

将Si基绝缘栅双极型晶体管(Insulated gate bipolar transistor,IGBT)芯片与SiC结型势垒肖特基二极管芯片按照双开关电路结构排布,开发了一种3.3.0 V等级混合SiC模块,对其设计方法、封装工艺、仿真、测试结果进行分析,并对标相同规格IGB... 详细信息

将Si基绝缘栅双极型晶体管(Insulated gate bipolar transistor,IGBT)芯片与SiC结型势垒肖特基二极管芯片按照双开关电路结构排布,开发了一种3.3.0 V等级混合SiC模块,对其设计方法、封装工艺、仿真、测试结果进行分析,并对标相同规格IGBT模块。混合SiC模块低空洞率焊接满足牵引领域高温度循环周次的要求,冗余式的连跳键合结构可以有效增强功率循环能力。采用双脉冲法测试动态性能,测试结果表明该混合SiC模块反向恢复时间减小了84%,反向恢复电流减小了89.5%,反向恢复能量减小了99%,一次开关产生的总损耗降低了43.3.。混合SiC模块消除了开关过程中电压和电流过冲现象,在高电压、大电流和高频率的应用工况下具有明显的优势。

关键词：绝缘栅双极型晶体管结型势垒肖特基二极管混合SiC模块

Flow Measuring of Pulverized Coal and Primary Air

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Flow Measuring of Pulverized Coal and Primary Air

A MARKET-ORIENTED PERFORMANCE APPRAISAL METHOD IN BUSINESS GROUPS

The Sixth International Conference on Measurement and Control of Granular Materials

作者： yang Xingsen Hao Weidong Yin Jing Wang Jiaxin Shandong electric power {3. institute Jinan 250002,China

Pulverized coal firing boilers are widely used in power *** mixture of pulverized coal and primary air flows into the burner,and then burns in the *** flow rate of the mixture,the ratio of pulverized coal to air and the pulverized coal distribution between burners are very important to the safe and economic operation of the *** flow rate measuring of pulverized coal/air mixture is the base of combustion optimization and efficiency promotion of the *** flow course of pulverized coal and primary air is a complex gas-solid two-phase flow *** the case of pulverized coal conveyed by exhaust air in power plants,the flow measuring remains unsolved and puzzles the *** of the mixing process shows that the pressure of primary air drops rapidly,which gives the hint to solve the *** to the energy conservation equation,study of the relationship between the mass flow rate of the pulverized coal and the pressure changes before and after the mixing process of exhaust convey system is carried out. Theoretical analysis reveals the way to determine the mass flow rate of pulverized coal powder by measuring the velocity,temperature and pressure drop of the primary air,and the experimental test proves the credibility of the measuring method As a result,the method is adopted in engineering applications successfully.

关键词： Pulverized coal primary air measure exhaust convey

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A MARKET-ORIENTED PERFORMANCE APPRAISAL METHOD IN BUSINESS G...

Construction of UHVAC test Base

2005年中国机械工程学会年会

作者： LIN Li, XU Sibao, ZHAO Yongqiang (School of Business Administration and Tourism Management, Yunnan University, Kunming, 650091 Yunnan electric power test and {3. institute, Kunming, 650051)

＜正＞After analyzing problems during the course of performance appraisal in business groups of China, a new performance appraisal method is proposed in this paper. Through establishing the visual markets among the critical procedures in business groups, the method emphasizes market and profit, and aims to strengthen employees’ market awareness and coordination awareness, which are the most important factors in a competitive enterprise cultural.

关键词： business group performance appraisal market

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electricity 2009年第4期20卷 15-19页

作者： yang Yingjian,Hu Yi,Wu Xiong,Wu Zhirong,Wan Qifa,Liu Xianjin and Cai Wei State Grid electric power {3. institute State Grid electric power research {3.

The construction of the UHVAC test base of SGCC is an important component of the pilot project on UHVAC power transmission and transformation in China. This paper introduces the layout, technical requirements and main test functions of the UHVAC test base as well as difficulties during construction. It lays stress on the characterization of a 1 000-kV single-circuit test line, a 1 000-kV one-tower double-circuit test line, a full voltage test site for UHV equipment, a climate laboratory, a corona cage and a long-wave-front impulse voltage generator.

关键词： AC Construction of UHVAC test Base test test

Function and Design Idea of UHVDC test Base

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electricity 2009年第1期20卷 38-43页

作者： Yu Yongqing, Li Guangfan, Sun Lin, Su Zhiyi and Lu Jiayu China electric power research {3. Zhao Fang China Hectrie power research institute

The function of the UHVDC test base of the State Grid Corporation of China (SGCC) is oriented to serve UHVDC power transmission and substation projects, especially power transmission from West China to East China, and to promote localization of UHVDC transmission and substation equipment. In essentials, this test base consists of UHVDC test transmission line, corona cage, outdoor test site, UHV test hall, pollution and environment laboratory, electromagnetic environment simulation test site, insulator laboratory, arrester laboratory and live equipment test field. This paper introduces the function and design idea of the test base, presents the main performance parameters of the above-mentioned test facilities, and summarizes the matters of concern when siting and planning.

关键词： UHVDC test Function and Design Idea of UHVDC test Base Design test

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一种耦合法拉第旋光器的全光纤电流传感器

中国电机工程学报 2020年第8期40卷 2670-2680页

作者：司马文霞王洋杨鸣王森王荆郑荣锋输配电装备及系统安全与新技术国家重点实验室(重庆大学) 国网陕西省电力公司电力科学研究院

电力系统暂态电流的实时感知对研究系统扰动、故障和控制保护具有重要意义。针对当前全光纤电流传感器难以同时兼顾宽频测量和宽温区适应性的难题,该文提出在传感光纤几何中点处耦合法拉第旋光器的直通式光路结构,并采用双线绕法绕制光... 详细信息

电力系统暂态电流的实时感知对研究系统扰动、故障和控制保护具有重要意义。针对当前全光纤电流传感器难以同时兼顾宽频测量和宽温区适应性的难题,该文提出在传感光纤几何中点处耦合法拉第旋光器的直通式光路结构,并采用双线绕法绕制光纤环。采用琼斯矩阵建立该结构的理论模型,通过磁场和光场耦合分析该传感器结构降低环境敏感性的传感机理。通过试验测试传感器的频率特性和温度特性,结果表明,该传感器具有良好的频率特性:10Hz～10kHz频响试验的幅值误差不超过2.3.,相移小于2°;3. A标准8/20ms雷电冲击电流响应试验的误差小于2.1%,波形相似度为0.9971,表明有效频带可覆盖至标准雷电流;温度试验表明,该结构可显著降低传感器的温度敏感性,在-20℃～60℃范围内的误差小于4.3.(传统基本结构为29%)。该文所提出的全光纤电流传感器结构具有较好的频率响应特性和优异的温度适应性,满足电网暂稳态电流实时感知的要求。

关键词：全光纤电流传感器法拉第旋光器冲击电流频率特性

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用于砂岩加固的锚杆的承载性能试验研究

岩土力学 2015年第S1期36卷 367-371页

作者：张琰郑卫锋朱照清中国电力科学研究院北京100192

针对中风化砂岩地质条件,开展了单锚基础和承台式群锚基础的现场足尺试验研究,得到了荷载-位移曲线,分析了基础的破坏模式和承载性能。通过锚筋应变测试,研究了锚杆基础的内力分布规律和有效锚固深度。研究结果表明,岩石锚杆基础应用于... 详细信息

针对中风化砂岩地质条件,开展了单锚基础和承台式群锚基础的现场足尺试验研究,得到了荷载-位移曲线,分析了基础的破坏模式和承载性能。通过锚筋应变测试,研究了锚杆基础的内力分布规律和有效锚固深度。研究结果表明,岩石锚杆基础应用于中风化砂岩地基分布地区,满足输电线路上部结构对基础承载力的要求,具有良好的经济和社会效益;当锚杆锚固深度小于有效锚固深度时,增加锚固深度和承台嵌岩深度能够有效地提高基础的抗拔承载性能;水平荷载不是基础发生破坏的控制因素,但水平荷载对群锚基础上拔稳定存在不利影响。

关键词：岩石锚杆砂岩地基输电线路极限抗拔承载力破坏模式

A DNA Computing Model for the Graph Vertex Coloring Problem Based on a Probe Graph

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Engineering 2018年第1期4卷 61-77页

作者： Jin xu xiaoli Qiang Kai Zhang Cheng Zhang Jing yang Key Laboratory of High Confidence Software Technologies of Ministry of Education Institute of Software School of Electronics Engineering and Computer SciencePeking University Beijing 100871 China institute of Novel Computer Science and Intelligent Software Guangzhou University Guangzhou 510006 China School of Computer Science Wuhan University of Science and Technology Wuhan 430081 China School of Control and Computer Engineering North China Electric Power University Beijing 102206 China

The biggest bottleneck in DNA computing is exponential explosion, in which the DNA molecules used as data in information processing grow exponentially with an increase of problem size. To overcome this bottleneck and improve the processing speed, we propose a DNA computing model to solve the graph vertex coloring problem. The main points of the model are as follows： The exponential explosion prob- lem is solved by dividing subgraphs, reducing the vertex colors without losing the solutions, and ordering the vertices in subgraphs; and the bio-operation times are reduced considerably by a designed parallel polymerase chain reaction （PCR） technology that dramatically improves the processing speed. In this arti- cle, a 3.colorable graph with 61 vertices is used to illustrate the capability of the DNA computing model. The experiment showed that not only are all the solutions of the graph found, but also more than 99% of false solutions are deleted when the initial solution space is constructed. The powerful computational capability of the model was based on specific reactions among the large number of nanoscale oligonu- cleotide strands. All these tiny strands are operated by DNA self-assembly and parallel PCR. After thou- sands of accurate PCR operations, the solutions were found by recognizing, splicing, and assembling. We also prove that the searching capability of this model is up to 0（3.59）. By means of an exhaustive search, it would take more than 896 000 years for an electronic computer （5 x 10^14 s-1） to achieve this enormous task. This searching capability is the largest among both the electronic and non-electronic computers that have been developed since the DNA computing model was proposed by Adleman＇s research group in 2002 （with a searching capability of 0（2^20））.

关键词： DNA computing Graph vertex coloring problem Polymerase chain reaction