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Analysis of S^(p)_(q) current systems by using corrected geomagnetic coordinates
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作者 陈鸿飞 陈耿雄 +1 位作者 彭丰林 徐文耀 《Chinese Journal of Polar Science》 2000年第1期59-66,共8页
The S^p_q equivalent current system of the quiet day geomagnetic variation in the polar region is very complicated. It is composed of several currents, such as the ionospheric dynamo current and the auroral electrojet... The S^p_q equivalent current system of the quiet day geomagnetic variation in the polar region is very complicated. It is composed of several currents, such as the ionospheric dynamo current and the auroral electrojet caused by the field aligned current. S p q is unsymmetrical in both polar regions. In this paper, the S p q current systems are analyzed in the corrected geomagnetic coordinates (CGM) instead of the conventional geomagnetic coordinates (GM), and the symmetries of the S p q current in different systems are compared. Then the causes of S p q asymmetry in the GM coordinates are discussed; the effects of each component in S p q are determined. 展开更多
关键词 s p q equivalent current systems corrected geomagnetic coordinates solar quiet day variation.
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Current Situation of China's Automotive Industry Enterprises
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《China's Foreign Trade》 1999年第7期27-29,共3页
Atpresent,thereare122completevehiclemanufacturersinChina,vehiclemanufacturersandover3000autoparts/componentsenterprises.149ofthemarejointventures.Thereare1.98millionemployeesintheindustrywith180.9billionyUanfixedasset... Atpresent,thereare122completevehiclemanufacturersinChina,vehiclemanufacturersandover3000autoparts/componentsenterprises.149ofthemarejointventures.Thereare1.98millionemployeesintheindustrywith180.9billionyUanfixedassetsand123billionyuannetvalue.Atthee... 展开更多
关键词 In current situation of China’s Automotive Industry Enterprises
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Current Situation of China's Thermal Power Generation Equipment & Its Development Perspective
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作者 Zhou Heliang China Electmtechnical Society 《Electricity》 1996年第4期12-13,共2页
1. The present manufacturing situation of China’s thermal power generation equipment By the year 1995. development of China’s electric power industry has experienced a course of a hundred years. Over a period of the... 1. The present manufacturing situation of China’s thermal power generation equipment By the year 1995. development of China’s electric power industry has experienced a course of a hundred years. Over a period of the initial 50 years. China’s development of electric power was slow. At the time of 1949, the total installed capacity in China was 1,850 MW and the electricity generated was only 4.3 billion kWh. During the past 46 years after 1949, her 展开更多
关键词 Its Development Perspective current situation of China’s Thermal Power Generation Equipment
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Current Situation and the Outlook of China's Natural Gas Industry
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作者 Gao Jie Chen Jianhui +1 位作者 Wei Kaihua Du Xiaoshuai 《China Oil & Gas》 CAS 2017年第1期17-22,共6页
Core indicators of China’s natural gas industry in 2016In 2016,China produced 132.82 bcm of natural gas and 1.61bcm of coal-to-gas,production amounts that were 1.5%and 15.8%higher than those of the previous year,resp... Core indicators of China’s natural gas industry in 2016In 2016,China produced 132.82 bcm of natural gas and 1.61bcm of coal-to-gas,production amounts that were 1.5%and 15.8%higher than those of the previous year,respectively.The imported gas volume was 38.34bcm through pipeline(up 9.0%from the previous year)and 33.74 bcm via LNG facilities(up 30.6%from 展开更多
关键词 In LNG current situation and the Outlook of China’s Natural Gas Industry THAN
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The Current State of China's Freshwater Resources and Related Suggestions
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作者 Wu Ruijin(Nanjing Institute of Geography and Limnology, CAS) 《Bulletin of the Chinese Academy of Sciences》 2001年第3期170-176,共7页
China has many lakes, marshlands and rivers. Due to their uneven geographical distribution and varied degrees of salinity, their exploitable freshwater resources are limited. In the wake of the highspeed growth of nat... China has many lakes, marshlands and rivers. Due to their uneven geographical distribution and varied degrees of salinity, their exploitable freshwater resources are limited. In the wake of the highspeed growth of national economy in recent years, human infringement upon their natural settings has been increasingly intense, leading to the degeneration of China's lacustrine ecosystems and the degradation of their surrounding environments. Lakes are shrinking and becoming more saline. In arid and semi-arid inland areas, some of them have even disappeared. In addition, lake water pollution and eutrophication in densely populated areas are getting worse, resulting in serious water shortages in some places. Silt deposition in lake basins, water surface shrinkage caused by hectic and irrational reclamation for farmland, the prevalence of flooding and water-logging calamities and ecosystem depletion caused by predatory exploitation of fishery resources, all of these have become restrictive factors in regional sustainable development. The author of this article suggests measures for the protection and sustainable exploitation of limnetic settings in China. 展开更多
关键词 OC The current state of China’s Freshwater Resources and Related suggestions LAKE
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Current Situations and Problems of Logistics for Guangxi Fresh Agricultural Products in the New Period and Recommendations 被引量:1
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作者 Shixiong ZHU 《Asian Agricultural Research》 2015年第10期39-43,共5页
In recent years,Guangxi realized consecutive bumper harvests in fresh agricultural products,leading increase of logistics demand;logistics infrastructure begins to take shape,and logistics of fresh agricultural produc... In recent years,Guangxi realized consecutive bumper harvests in fresh agricultural products,leading increase of logistics demand;logistics infrastructure begins to take shape,and logistics of fresh agricultural products takes on diversified development form with wholesale market as main form. However,traditional fresh agricultural products are not selling well and it lacks construction of supply chain; the construction of logistics information system for fresh agricultural products lags behind; organizational level of production and operation of fresh agricultural products is low. Through analyzing current situations and existing problems of logistics of Guangxi fresh agricultural products in the new period( 21 st century),this paper came up with recommendations for developing logistics of fresh agricultural products of Guangxi. Government should increase policy and financial support,build and manage supply chain of fresh agricultural products,accelerate construction of logistics information system for agricultural products,and improve organizational level of logistics of fresh agricultural products,to ensure healthy development of logistics of fresh agricultural products in Guangxi. 展开更多
关键词 LOGIsTICs of FREsH AGRICULTURAL products current s
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Current Situations of Competitive Scientific Research Projects for Agri-scientific Research Institutions: A Case Study of Tropical Crops Genetic Resources Institute of Chinese Academy of Tropical Agricultural Sciences
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作者 Haiyan LUO Qingqun YAO +1 位作者 Lizhen CHEN Yu ZHENG 《Asian Agricultural Research》 2015年第10期77-82,共6页
This paper collected and arranged competitive scientific research projects undertaken by Tropical Crops Genetic Resources Institute of Chinese Academy of Tropical Agricultural Sciences in 2003-2014. Through statistica... This paper collected and arranged competitive scientific research projects undertaken by Tropical Crops Genetic Resources Institute of Chinese Academy of Tropical Agricultural Sciences in 2003-2014. Through statistical analysis on quantity of projects,funded amount,age of person responsible,professional title of person responsible,academic degree of person responsible,research object,it discussed relevant characteristics and rules. Finally,it came up with pertinent measures and recommendations,in the hope of providing services for decision-making and scientific and technological management. 展开更多
关键词 COMPETITIVE sCIENTIFIC research PROJECTs current s
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Analysis On the Current Status and Future Development Trend of China's Lithium Industry
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《China Nonferrous Metals Monthly》 2016年第9期7-9,共3页
Recently,the 2016 Lithium Industry Forum,an event hosted by the China Nonferrous Metals Industry Association Lithium Branch,opened in Xining,Qinghai Province.Li Bingxin,Deputy Secretary-general of the China Nonferrous... Recently,the 2016 Lithium Industry Forum,an event hosted by the China Nonferrous Metals Industry Association Lithium Branch,opened in Xining,Qinghai Province.Li Bingxin,Deputy Secretary-general of the China Nonferrous Metals Industry Association Lithium Branch,shared the operation 展开更多
关键词 LI Analysis On the current status and Future Development Trend of China’s Lithium Industry
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Consistency evaluation of the current distribution of short-circuit tests in AT feeding systems for high-speed railways 被引量:1
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作者 Qing-an Ma Wei Liu 《Journal of Modern Transportation》 2018年第3期163-172,共10页
To improve the accuracy of fault location system, several short-circuit tests need to be conducted before being brought into service in autotransformer (AT) feeding systems for high-speed railways in China. However,... To improve the accuracy of fault location system, several short-circuit tests need to be conducted before being brought into service in autotransformer (AT) feeding systems for high-speed railways in China. However, no systematic algorithm yet exists to evaluate the consistency of the current distribution of short-circuit tests. A methodology is proposed in this paper to address this problem. Based on Kirchhoff’s current law and the generalized method of symmetrical components, the current deviations of the AT feeding systems are analysed and then normalized with the short-circuit current as they vary greatly with systems and short-circuit sites. It is also found that the short-circuit current varies with the calculation methods, and its unbiased standard deviation also reflects the consistency of the short-circuit test. The mean and maximum of the current deviations, as well as the unbiased standard deviation of the short-circuit current, show the consistency of the short-circuit test from different aspects,although the last two items are highly relevant. Therefore, a unified evaluation index is defined as the sum of the three items, and then applied in two case studies to test its performance. The results show that, the proposed index canclearly distinguish the consistency of the short-circuit tests and may be used to sort the short-circuit tests for fault location systems. Besides, some short-circuit tests may have very poor consistency indices, and thus are not applicable to the tuning of fault location systems. In the authors’ opinion, the determination of the threshold of the proposed index needs further investigation. 展开更多
关键词 Autotransformer feeding system short-circuittest Consistency evaluation Kirchhoff’s current law Generalized method of symmetrical components
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Magnetite Quartzite-Type Iron Ores – China's Most Important Current Iron Ore Source 被引量:1
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作者 HAO Ziguo FEI Hongcai +1 位作者 HAO Qingqing Susan TURNER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第4期1329-1331,共3页
China is abundant in iron-ore resources, with proven ore reserves of 576.62×10^8 t and proven reserves of 210×10^8 t, containing an average iron content of 33%. However, the rich iron-ore reserves of 10.85&#... China is abundant in iron-ore resources, with proven ore reserves of 576.62×10^8 t and proven reserves of 210×10^8 t, containing an average iron content of 33%. However, the rich iron-ore reserves of 10.85×10^8 t only account for 1.9% of all proven reserves. China's iron-ore resources are characterized by many lean ores and a few rich ones. 展开更多
关键词 China’s Most Important current Iron Ore source Magnetite Quartzite-Type Iron Ores TFe
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EFFECT OF DIFFERENT WAVEFORM'S ALTERNATING CURRENT ON THE INCISION'S SENSITIVITY
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作者 Shu Ping BIHong GAO (H.KAO) Department of Chemistry, Nanjing University, Nanjing, 210008 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第11期983-984,共2页
Compared with the conventionally used i=iosinωt alternating current, using asymmetric triangular and pulse wave as input signals can greatly enhance the incision's sensitivity of 'dE/dt-E'oscillogram.
关键词 KBR EFFECT OF DIFFERENT WAVEFORM’s ALTERNATING current ON THE INCIsION’s sENsITIVITY
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Investigation on 10/350 Crowbar Pulse Current Circuit
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作者 姚学玲 陈景亮 孙伟 《Plasma Science and Technology》 SCIE EI CAS CSCD 2010年第4期494-498,共5页
Structure of main air discharging switch and a crowbar TVS (triggered vacuum switch) are designed and their triggering characteristics are investigated. The experimental results showed that for TVS the operating vol... Structure of main air discharging switch and a crowbar TVS (triggered vacuum switch) are designed and their triggering characteristics are investigated. The experimental results showed that for TVS the operating voltage range is from 1.3 kV to 120 kV, its maximum delay time is 400 ns and its jitter is 4-10 ns. Based on these results the crowbar 10/350μs (i.e., with a front time of 10μs and a duration of 350 μs) pulse current circuit and its controlling circuit are designed. With a 10μF stored capacitor C and a 6 μF waveform forming induction, a pulse current is generated with a maximum of 100 kA, front time of 10 ns and duration of 350μs. This pulse waveform can be used for testing SPD (surge protective devices). 展开更多
关键词 crowbar circuit triggered vacuum switch triggering characteristics 10/350 μs pulse current waveform
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Discussions on China's Current Economic Situation
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作者 Xiangzi Nanfengchuang 《China's Foreign Trade》 1999年第12期4-6,共3页
It can be certain that the series of related policies will create a breakthrough in China’s economy.The inflation rate in China is low at present, and this is the right moment to adopta currency policy to raise direc... It can be certain that the series of related policies will create a breakthrough in China’s economy.The inflation rate in China is low at present, and this is the right moment to adopta currency policy to raise directly the income of peasants and low-income families. 展开更多
关键词 Discussions on China’s current Economic situation In
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CHINA'S CURRENT NATURAL GAS RESOURCES
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《China Oil & Gas》 CAS 1999年第2期84-85,共2页
关键词 GAs CHINA’s current NATURAL GAs REsOURCEs
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REALIZATION OF THE RMB'S CONVERTIBILITY UNDER THE CURRENT ACCOUNT AND ITS INFLUENCE
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作者 Ji Caihui 《China's Foreign Trade》 1996年第11期8-9,6,共3页
It was approved by the State Council in I984 to establish economicand technological development zones in 14 coastal port cities tofunction as windows for those cities to attract foreign investment,introduce advanced t... It was approved by the State Council in I984 to establish economicand technological development zones in 14 coastal port cities tofunction as windows for those cities to attract foreign investment,introduce advanced technology and management methods andexpand the export-oriented economy.Since 1992,18 other developmentzones have been approved by the Council,increasing the number ofsuch zones to 32. 展开更多
关键词 REALIZATION OF THE RMB’s CONVERTIBILITY UNDER THE current ACCOUNT AND ITs INFLUENCE WILL Us RATE ITs
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Zeeman effects on Josephson current in d-wave superconductor/d-wave superconductor junctions
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作者 廖艳华 董正超 +1 位作者 尹在峰 付浩 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第5期1893-1901,共9页
This paper solves a self-consistent equation for the d-wave superconducting gap and the effective exchange field in the mean-field approximation, and studies the Zeeman effects on the d-wave superconducting gap and th... This paper solves a self-consistent equation for the d-wave superconducting gap and the effective exchange field in the mean-field approximation, and studies the Zeeman effects on the d-wave superconducting gap and thermodynamic potential. The Josephson currents in the d-wave superconductor(S)/insulating layer(I)/d-wave S junctions are calculated as a function of the temperature, exchange field, and insulating barrier strength under a Zeeman magnetic field on the two d-wave Ss. It is found that the Josephson critical currents in d-wave S/d-wave S junction to a great extent depend on the relative orientation of the effective exchange field of the two S electrodes, and the crystal orientation of the d-wave S. The exchange field under certain conditions can enhance the Josephson critical current in a d-wave S/I/d-wave S junction. 展开更多
关键词 Zeeman effect d-wave s/d-wave s ferromagnetic d-wave superconductor Josephson current
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S zorb装置转剂线隐患风险识别与排查对策
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作者 杨富淋 赵帅 张久峰 《全面腐蚀控制》 2025年第10期146-149,共4页
S zorb再生系统转剂线易发生冲刷、磨损,转剂线泄漏会导致吸附剂无法实现循环再生,这将迫使S zorb装置停工,那么预判腐蚀风险、排查隐患部位就尤为重要。本文针对中石化某厂2号S zorb分析预判了氮气和吸附剂气提升管前、后段易磨损管线... S zorb再生系统转剂线易发生冲刷、磨损,转剂线泄漏会导致吸附剂无法实现循环再生,这将迫使S zorb装置停工,那么预判腐蚀风险、排查隐患部位就尤为重要。本文针对中石化某厂2号S zorb分析预判了氮气和吸附剂气提升管前、后段易磨损管线,大曲率弯头等为腐蚀风险区域,介绍了脉冲涡流技术及聚声波导在线测厚技术的检测原理和特点,使用脉冲涡流对预判的风险区域进行扫查并确定减薄位置,用聚声波导在线测厚实时监测隐患位置的壁厚减薄程度,结果表明,达到了排查隐患的目的,预警了风险。 展开更多
关键词 隐患排查 脉冲涡流 在线测厚 s zorb装置
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基于交轴磁场调节的漏磁通可控永磁同步电动机最小弱磁电流控制
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作者 全力 金志伟 +2 位作者 徐磊 朱孝勇 范文杰 《江苏大学学报(自然科学版)》 北大核心 2026年第1期55-63,共9页
为满足电动汽车应用领域对驱动电动机大转矩、宽调速范围、高效率等的需求,结合漏磁可控型永磁(flux leakage controllable permanent magnet,FLCPM)电动机高速低磁通、重载高磁通的特性,提出一种基于交轴磁场调节的弱磁电流最小调速控... 为满足电动汽车应用领域对驱动电动机大转矩、宽调速范围、高效率等的需求,结合漏磁可控型永磁(flux leakage controllable permanent magnet,FLCPM)电动机高速低磁通、重载高磁通的特性,提出一种基于交轴磁场调节的弱磁电流最小调速控制策略.利用交轴磁场重构弱磁控制时i_(d)、i_(q)电流分配,有限调节永磁体漏磁磁通,间接实现气隙磁通控制.在此基础上,为减小漏磁通变化对电流分配计算及去磁电流计算的影响,引入最小i_(s)电流弱磁约束条件与在线调节判断,优选i_(d)、i_(q)分配量,提高弱磁运行效率.进行FLCPM电动机的i_(q)电流弱磁控制和最小弱磁电流控制试验,并分析了其电流大小、调速特性和弱磁效率特点.结果表明:在FLCPM电动机上的传统i_(d)电流弱磁存在过度弱磁,且最小弱磁电流控制拥有更小的is电流、更宽的调速范围和更高的弱磁效率,i_(s)电流最高减少了2.83%、弱磁效率最高可达91.0%. 展开更多
关键词 永磁电动机 漏磁可控 i_(q)电流弱磁 最小弱磁调速 最小i_(s)电流弱磁 高弱磁效率
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共源-共栅组态S^2I电流存储单元及其性能 被引量:3
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作者 李拥平 石寅 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第10期1106-1111,共6页
针对原型S2 I开关电流存储单元性能上的一些弱点 ,提出了共源 共栅组态的S2 I电流存储单元 (简称CS2 I)新结构 ,使其关键速度与精度性能得到较好的改善 .相同器件尺寸下的S2 I与CS2 I单元电路相比 ,后者速度性能提高了 1 6倍 ,两种电路... 针对原型S2 I开关电流存储单元性能上的一些弱点 ,提出了共源 共栅组态的S2 I电流存储单元 (简称CS2 I)新结构 ,使其关键速度与精度性能得到较好的改善 .相同器件尺寸下的S2 I与CS2 I单元电路相比 ,后者速度性能提高了 1 6倍 ,两种电路结构同样应用于延迟单元和双采样双线性积分器功能部件的HSPICE仿真表明 :CS2 I方式组成的延迟单元的精度提高了 5倍 ,双采样双线性积分器的三次谐波减少了 15dB . 展开更多
关键词 共源-共栅组态 开关电流 sI s^2I存储单元 精度 Cs^2I
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电流探头S参数校准方法的研究 被引量:1
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作者 周忠元 蒋全兴 +1 位作者 蒋宇 方耿 《计量学报》 CSCD 北大核心 2006年第4期380-383,共4页
采用S参数法对电流探头特性进行校准,讨论S参数校准过程中的具体技术细节,并与传统校准方法的校准结果进行比较。经验证,电流探头的S参数法校准结果真实可信,尤其适合100MHz以上电流探头的特性校准。在此基础上,利用注入电流探头对同轴... 采用S参数法对电流探头特性进行校准,讨论S参数校准过程中的具体技术细节,并与传统校准方法的校准结果进行比较。经验证,电流探头的S参数法校准结果真实可信,尤其适合100MHz以上电流探头的特性校准。在此基础上,利用注入电流探头对同轴电缆的屏蔽衰减进行了测试分析。 展开更多
关键词 计量学 电流探头 s参数 校准方法 转移阻抗
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