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自动化车辆基地应答器变位系统研究
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作者 程春阳 《城市轨道交通研究》 北大核心 2024年第10期229-234,共6页
[目的]自动化车辆基地检修地沟内的应答器对车辆检修造成的限制与影响日益凸显,故有必要研究可变位置的应答器安装机构代替传统固定式应答器安装支架。[方法]针对车辆检修工艺的实际需求,设计了应答器变位系统的三级架构体系,包括总控... [目的]自动化车辆基地检修地沟内的应答器对车辆检修造成的限制与影响日益凸显,故有必要研究可变位置的应答器安装机构代替传统固定式应答器安装支架。[方法]针对车辆检修工艺的实际需求,设计了应答器变位系统的三级架构体系,包括总控台、电控箱以及变位机构。该系统支持多种控制模式,包括人工直接控制、与智能列检机器人的联动控制,以及与信号系统SPKS(人员防护开关)的自动联动控制,确保了操作的灵活性与精准性。同时,系统内置了激光到位检测功能及人工手动闭锁等安全冗余措施,满足信号系统对高可靠性的严格要求。[结果及结论]在车辆基地的实际应用中,应答器变位系统巧妙利用了轨道桥结构柱间的空间位置,实现了应答器从固定安装到可变位置安装的转变。这一变革不仅保障了全自动运行列车在收发车过程中的精准高效,还极大地便利了车辆基地内列检人员及智能列检机器人的作业,有效解决了因应答器固定安装而导致的检修作业受限问题。 展开更多
关键词 城市轨道交通 车辆基地 全自动运行 应答器 变位系统 优化设计
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变位焊接机器人系统的运动建模及分析 被引量:3
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作者 应灿 翟敬梅 张铁 《机床与液压》 北大核心 2012年第13期143-146,共4页
研究变位焊接机器人系统的同步协调运动的实现。在SolidWorks2010软件中建立了该机器人系统模型,同时给出了其同步协调运动的算法和实现步骤;以半球面空间螺旋曲线为焊接路径,对机器人与变位机的同步协调运动进行仿真分析,发现焊枪末端... 研究变位焊接机器人系统的同步协调运动的实现。在SolidWorks2010软件中建立了该机器人系统模型,同时给出了其同步协调运动的算法和实现步骤;以半球面空间螺旋曲线为焊接路径,对机器人与变位机的同步协调运动进行仿真分析,发现焊枪末端能够以较高精度和较好位姿跟踪该焊缝曲线,为变位焊接机器人系统的同步协调运动的实现提供了理论依据。 展开更多
关键词 焊接机器人系统 运动建模 同步协调运动
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二组元连续变位光学系统
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作者 洪善贤 《云光技术》 1992年第1期1-8,共8页
关键词 光学系统 倍原理 二组元
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COSMIC资料在GRAPES全球三维变分同化系统的初步研究 被引量:17
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作者 唐细坝 薛纪善 《热带气象学报》 CSCD 北大核心 2009年第5期521-531,共11页
利用COSMIC获得的GPS无线电掩星数据所反演得到的大气温湿度廓线资料,在GRAPES全球三维变分同化系统中做连续循环同化试验,研究了加入COSMIC资料后得到的GRAPES分析场及其5天中期预报是否有所改善。研究结果表明:通过加入COSMIC资料连... 利用COSMIC获得的GPS无线电掩星数据所反演得到的大气温湿度廓线资料,在GRAPES全球三维变分同化系统中做连续循环同化试验,研究了加入COSMIC资料后得到的GRAPES分析场及其5天中期预报是否有所改善。研究结果表明:通过加入COSMIC资料连续循环同化得到的分析场,相对原来没有加COSMIC资料连续同化出来的GRAPES分析场有明显改善,由此GRAPES全球模式全球5天中期预报水平有明显提高,其中加入没有稀疏化后COSMIC资料对南半球GRAPES分析场的改善以及GRAPES全球模式5天中期预报水平的提高都比较显著;加入稀疏化后的COSMIC资料对北半球GRAPES分析场的改善以及GRAPES全球模式5天中期预报水平的提高都有比较显著的效果。 展开更多
关键词 数值预报 COSMIC资料同化 GPS无线电掩星 GRAPES全球三分同化系统
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整机全姿态自动变位柔性翻转工装研究 被引量:1
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作者 王振文 樊迪 +1 位作者 赵荣 郭龙江 《航空制造技术》 CSCD 北大核心 2022年第8期93-97,共5页
为满足飞机制造过程中整机全姿态的补铆、涂胶等装配工作需求,需对整机执行全姿态翻转。传统翻转工装存在翻转精度差、控制系统自动化程度不高、工装复用性低等缺点。因此,基于整机全姿态翻转工序,研究并实现一种整机全姿态柔性翻转工... 为满足飞机制造过程中整机全姿态的补铆、涂胶等装配工作需求,需对整机执行全姿态翻转。传统翻转工装存在翻转精度差、控制系统自动化程度不高、工装复用性低等缺点。因此,基于整机全姿态翻转工序,研究并实现一种整机全姿态柔性翻转工装。以分体式龙门结构,通用固持接头及自动变位控制系统实现对飞机整机的360°柔性翻转。通过调整分体龙门架的位置,适应不同尺寸的飞机产品,利用过渡工装与通用固持接头实现整机机体在翻转装置上的柔性夹持。利用自动变位控制系统进行翻转定位,确保整机翻转精度及可靠性。该工装可满足不同机型产品的整机装配工作,相较于传统工装可有效减少工装制造成本,提升工装的翻转精度、操作空间开敞性及工装通用性。 展开更多
关键词 整机 柔性 翻转工装 龙门架 自动变位系统
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PDC钻头自动焊接系统的设计 被引量:1
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作者 徐建飞 刘先广 徐建雄 《石油机械》 北大核心 2003年第C00期47-48,共2页
针对PDC钻头复合片与钻头基体手工焊接时,焊接温度常无法检测与控制,难以保证焊接质量,导致复合片齿柱断裂、脱落和复合片表层脱落,为此而设计了PDC钻头自动焊接系统。该系统由复合片焊接温控及钻头自动焊接专用变位系统组成,通过PLC自... 针对PDC钻头复合片与钻头基体手工焊接时,焊接温度常无法检测与控制,难以保证焊接质量,导致复合片齿柱断裂、脱落和复合片表层脱落,为此而设计了PDC钻头自动焊接系统。该系统由复合片焊接温控及钻头自动焊接专用变位系统组成,通过PLC自动控制焊接温度、时间、变位机构和操作机构等,实现了复合片与钻头基体自动焊接,保证了焊接质量,提高了焊接效率。 展开更多
关键词 PDC钻头 自动焊接系统 设计 复合片 PLC 控制系统 变位系统 石油钻头
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PDC钻头自动焊接技术 被引量:4
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作者 王鑫 徐建飞 郝荣明 《焊接》 北大核心 2005年第12期48-51,共4页
在对PDC钻头的焊接性进行分析的基础上,选择了火焰加热的钎焊方法,研制出了适用于PDC钻头火焰钎焊,并具有专利技术的复合片焊接温度测控系统和数控变位操作系统,实现了复合片与钻头基体焊接工艺参数的自动控制和复合片焊接位置的数控定... 在对PDC钻头的焊接性进行分析的基础上,选择了火焰加热的钎焊方法,研制出了适用于PDC钻头火焰钎焊,并具有专利技术的复合片焊接温度测控系统和数控变位操作系统,实现了复合片与钻头基体焊接工艺参数的自动控制和复合片焊接位置的数控定位,在稳定PDC钻头的焊接质量、提高焊接效率、降低劳动强度方面迈出了重要的一步。 展开更多
关键词 PDC钻头 复合片 火焰钎焊 温控系统 数控操作系统 PLC
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Linearity of Removal in the Proeess of Optical Element Polishing
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作者 辛企明 《Journal of Beijing Institute of Technology》 EI CAS 1992年第2期122-131,共10页
In the light of some assumptions that are very close to the practical working conditions,a very complicated polishing process of optical element can be simplified as a linear and shift invariant system that is relatd ... In the light of some assumptions that are very close to the practical working conditions,a very complicated polishing process of optical element can be simplified as a linear and shift invariant system that is relatd only to the speed,pres- sure and time of processing.In polishing,the removed material can be represented and entreated by the convolution of the removal function of polishing head and the dwell function.The properties of removal function are presented.The assumptions and methods given by the author have been shown to be correct and applicable by experiments using a ring lap to polish the optical surfac. 展开更多
关键词 optical element POLISHING convolution/linear and shift invariant system
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Theory and Practice of the SSDM for GPS Deformation Monitoring 被引量:2
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作者 Lü Wei-cai XU Shao-quan 《Journal of China University of Mining and Technology》 EI 2006年第2期156-161,共6页
Global Positioning System technique is widely used to monitor the deformations of all kinds of buildings and constructions. According to the characteristics of the high precise GPS deformation monitoring, the theory a... Global Positioning System technique is widely used to monitor the deformations of all kinds of buildings and constructions. According to the characteristics of the high precise GPS deformation monitoring, the theory and practice of the SSDM (Similar Single-Difference Methodology) for GPS deformation monitoring are introduced synthetically from the background, the essential mathematic model,the error sources and control measures, the monitoring schemes and the software development. Some arguments are also given in the form of reference literatures. Based on the first period observation results of the GPS monitor network, SSDM solves the monitoring points' deformation values at a single epoch from carder phases directly, without needing to solve baseline vectors and network adjustment. The SSDM avoids the troublesome problem of detecting and repairing cycle slips, and can be used in static and dynamic deformation monitoring. In the SSDM, the unknown parameters have no relation to the numbers of satellites. If the number of synchronous satellites between stations is not less than two, the monitoring point's deformation information can be solved easily. 展开更多
关键词 GPS Deformation monitoring Single epoch SSDM Methodology SUMMARIZATION
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ANALYSIS ON STRUCTURE OF TYPHOON LONGWANG BASED ON GPS DROPWINSONDE DATA 被引量:2
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作者 舒守娟 彭犁然 《Journal of Tropical Meteorology》 SCIE 2011年第3期193-201,共9页
As one of the most severe typhoons in the year 2005,Typhoon Longwang is chosen as a case study in this article.Throughout its life,two surveillance flights are carried out on it.Different from previous studies,GPS(glo... As one of the most severe typhoons in the year 2005,Typhoon Longwang is chosen as a case study in this article.Throughout its life,two surveillance flights are carried out on it.Different from previous studies,GPS(global positioning system)Dropwinsonde data collected from the Dropwinsonde Observations for Typhoon Surveillance near the Taiwan Region is chosen to present the thermodynamic and kinetic structure at its two different stages of development.This study suggests that not only kinetic structure but also thermodynamic structure of Longwang are more robust in the second surveillance than the first surveillance,with stronger and larger circulation and a warmer core.Further research shows that the environmental vertical wind shear mainly contributes to the asymmetric structure of the typhoon.The strong vertical wind shear not only results in the distinct asymmetric structure,but also restrains the development of the typhoon. 展开更多
关键词 TYPHOON structure characteristics observational analysis dropwindsonde
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Surgicopathological classification of hepatic space-occupying lesions:A single-center experience with literature review 被引量:28
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作者 Wen-Ming Cong Hui Dong +2 位作者 Lu Tan Xu-Xu Sun Meng-Chao Wu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第19期2372-2378,共7页
Accompanying rapid developments in hepatic surgery,the number of surgeries and identifications of histological types of primary hepatic space-occupying lesions (PHSOLs) have increased dramatically.This has led to many... Accompanying rapid developments in hepatic surgery,the number of surgeries and identifications of histological types of primary hepatic space-occupying lesions (PHSOLs) have increased dramatically.This has led to many changes in the surgicopathological spectrum of PHSOLs,and has contributed to a theoretical basis for modern hepatic surgery and oncological pathology.Between 1982 and 2009 at the Eastern Hepatobiliary Surgery Hospital (EHBH) in Shanghai,31 901 patients underwent surgery and were diagnosed as having a PHSOL.In this paper,we present an analysis of the PHSOL cases at the EHBH for this time period,along with results from a systematic literature review.We describe a surgicopathological spectrum comprising more than 100 types of PHSOLs that can be stratified into three types:tumor-like,benign,and malignant.We also stratified the PHSOLs into six subtypes derived from hepatocytes;cholangiocytes;vascular,lymphoid and hemopoietic tissues;muscular,fibrous and adipose tissues;neural and neuroendocrine tissues;and miscellaneous tissues.The present study provides a new classification system that can be used as a current reference for clinicians and pathologists to make correct diagnoses and differential diagnoses among various PHSOLs. 展开更多
关键词 Liver tumors Tumor-like lesions PATHOLOGY IMMUNOHISTOCHEMISTRY CLASSIFICATION
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Leaf Vein Density: A Possible Role as Cooling System 被引量:3
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作者 Mario Pagano Paolo Storchi 《Journal of Life Sciences》 2015年第7期299-303,共5页
The study of leaves and their architecture evolution is important for understanding the fluid dynamics of water movement in /eaves. Recent studies have shown how these systems can be involved in the performance of phy... The study of leaves and their architecture evolution is important for understanding the fluid dynamics of water movement in /eaves. Recent studies have shown how these systems can be involved in the performance of physiological aspects, which are directly connected with the density of the vascular network and stomata per unit of surface area. The vein architecture, beyond being essential for a mechanical support of the leaf, can also play a crucial role in the efficiency of the photosynthesis. The aim of the present work was to highlight the possible role of leaves vein network as cooling system. The results support the hypothesis that the vascular system of grape leaves is correlated with leaf temperature. 展开更多
关键词 LEAVES TEMPERATURE PLANT vein density.
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Monitoring slope deformation using a 3-D laser image scanning system: a case study 被引量:10
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作者 YUE Depeng WANG Jiping +2 位作者 ZHOU Jinxing CHEN Xiaoxue REN Huijun 《Mining Science and Technology》 EI CAS 2010年第6期898-903,共6页
An ILRIS-36D 3-D laser image scanning system was used to monitor the Anjialing strip mine slope on Pingshuo in Shanxi province. The basic working principles, performance indexes, features and data collection and proce... An ILRIS-36D 3-D laser image scanning system was used to monitor the Anjialing strip mine slope on Pingshuo in Shanxi province. The basic working principles, performance indexes, features and data collection and processing methods are illus-trated. The point cloud results are analyzed in detail. The rescale range analysis method was used to analyze the deformation char-acteristics of the slope. The results show that the trend of slope displacement is stable and that the degree of landslide danger is low. This work indicates that 3-D laser image scanning can supply multi-parameter, high precision real time data over long distances. These data can be used to study the distortion of the slope quickly and accurately. 展开更多
关键词 3-D laser image scanning system ILRIS-36D -distortion SLOPE MONITOR
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Quantum Fourier Transform and Phase Estimation in Qudit System 被引量:4
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作者 曹业 彭世国 +1 位作者 郑超 龙桂鲁 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第5期790-794,共5页
The quantum Fourier transform and quantum phase estimation are the key components for many quantum algorithms, such as order-finding, factoring, and etc. In this article, the general procedure of quantum Fourier trans... The quantum Fourier transform and quantum phase estimation are the key components for many quantum algorithms, such as order-finding, factoring, and etc. In this article, the general procedure of quantum Fourier transform and phase estimation are investigated for high dimensional case run in a qudit quantum computer, and the quantum circuits are They can be seen as subroutines in a main program given. 展开更多
关键词 quantum fourier transform qudit system phase estimation
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Quantum Entanglement Creating and Evolving in Two Charge Qubits Coupling to a Nanomechanical Resonator System 被引量:1
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作者 张风阳 石瑛 +1 位作者 李崇 宋鹤山 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第8期385-388,共4页
We investigate the coupling of two superconducting quantum interference devices (SQUIDs) via a metallicnanomechanical resonator (NAMR),and bring out the effective interaction between the two SQUIDs.By constructingthe ... We investigate the coupling of two superconducting quantum interference devices (SQUIDs) via a metallicnanomechanical resonator (NAMR),and bring out the effective interaction between the two SQUIDs.By constructingthe evolution operator,we also study the evolvement of entanglement in this composed system. 展开更多
关键词 Josephson junction quantum information
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Characteristics of Multipath Effects in GPS Dynamic Deformation Monitoring
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作者 HUANG Shengxiang JIN Xiangsheng YANG Baocen 《Geo-Spatial Information Science》 2006年第2期79-83,共5页
ABSTRACT The multipath has long been considered a major error source in GPS applications .The characteristics 0f the GPS signal multipath effects are analyzed. based on which an experiment that considers the characte... ABSTRACT The multipath has long been considered a major error source in GPS applications .The characteristics 0f the GPS signal multipath effects are analyzed. based on which an experiment that considers the characteristics of dynamic deformation monitoring has been carried out. The solution results of observation data in two successive days are processed by a method,which combines the wavelet filtering and the differential correction betweentwo successive days. The research demonstrates that the multipath errors have stronger repeatability on successive days;after significantly mitigating the influence of multipath effects,the accuracy of three-dimensional positioning for GPS dynamic deformation monitoring can attain the mm level,an obvious accuracy improving particularly invertical component.The characteristics of GPS signal multipath,th eexperimental scheme and the qualitative and quantitative analysis of results are detailed. 展开更多
关键词 GPS dynamic deformation monitoring multipath effects error characteristic
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Multipartite Entanglement Transfer from Multi-Mode Coherent State to Spin Qubits
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作者 任杰 朱士群 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第6期1035-1038,共4页
The multipartite entanglement transfer from continuous variable system to spin qubits is investigated. We select multi-mode coherent field as continuous variable field. It is found that the qubits can not gain tripart... The multipartite entanglement transfer from continuous variable system to spin qubits is investigated. We select multi-mode coherent field as continuous variable field. It is found that the qubits can not gain tripartite entanglement for states of close to GHZ state from the multi-mode coherent field. Moreover, the ability of the qubits gain the tripartite entanglement for states close to W state and bipartite entanglement from the continuous variable system is depended on the phase of multi-mode coherent field. 展开更多
关键词 entanglement transfer multi-mode coherent field
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Hydraulic Properties of Rocky Mountain First-Order Alluvial Systems and Diurnal Water-Level Fluctuations in Riparian Vegetation: An Analysis in Hay Creek, Whitetail Basin, Montana
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作者 W.D. Weight K. Chandler 《Journal of Environmental Science and Engineering》 2010年第9期12-23,共12页
The hydrogeology of first-order streams have been evaluated from 2007 to 2009 as part of the Whitetail Basin Watershed Restoration Project in Hay Creek Canyon located 25 km north of Whitehall Montana, USA. An in-depth... The hydrogeology of first-order streams have been evaluated from 2007 to 2009 as part of the Whitetail Basin Watershed Restoration Project in Hay Creek Canyon located 25 km north of Whitehall Montana, USA. An in-depth study of the riparian area hydrogeology started in the fall of 2007 with the installation of more than 40 hand-augered deeper (〉 1 m) wells to complement preexisting driven metal pipe piezometers (± 1 m) installed in four first-order drainages. Two zones within the shallow alluvial systems were identified. This paper presents the results of a concentrated study conducted in the Hay Creek drainage within the tWO zones. Data loggers placed in some of the wells led to a gradual understanding of the water-level patterns in different vegetative types (Douglas Fir, Aspen, Willow-Alder. and Grass-Sagebrush) over the various seasons. The deeper water-level responses change from seasonal patterns to strongly diurnal during summer months. Diurnal patterns continue until leaves drop from riparian vegetation. This was expected, however, the Douglas fir trees show the same pattern. Near the end of the study a full year of water-level data showing the seasonal behavior changes were collected. Resaturation of the upper zone occurs in the fall with sources of recharge coming from up-drainage. A detailed evaluation of water-level responses from up-drainage to down-drainage piezometers occurs in a "wave-like" resaturation phenomenon that allows one to estimate the bulk hydraulic conductivity of the "alluvial system" aquifer using principles of Darcy's Law. The methods used to evaluate the hydraulic properties and seasonal water-level patterns are presented. 展开更多
关键词 Riparian areas HYDROGEOLOGY first-order streams DIURNAL water-level patterns aquifer properties prescribed fire coniferencroachment.
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Grid tie inverter energy stabilizing in smart distribution grid with energy storage 被引量:1
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作者 孙秋野 李大双 +1 位作者 褚恩辉 张艺缤 《Journal of Central South University》 SCIE EI CAS 2014年第6期2298-2305,共8页
With the growing deployment of smart distribution grid,it has become urgent to investigate the smart distribution grid behavior during transient faults and improve the system stability.The feasibility of segmenting la... With the growing deployment of smart distribution grid,it has become urgent to investigate the smart distribution grid behavior during transient faults and improve the system stability.The feasibility of segmenting large power grids and multiple smart distribution grids interconnections using energy storage technology for improving the system dynamic stability was studied.The segmentation validity of the large power grids and smart distribution grid inverter output interconnections power system using energy storage technology was proved in terms of theoretical analysis.Then,the influences of the energy storage device location and capacity on the proposed method were discussed in detail.The conclusion is obtained that the ESD optimal locations are allocated at the tie line terminal buses in the interconnected grid,respectively.The effectiveness of the proposed method was verified by simulations in an actual power system. 展开更多
关键词 smart distribution grid grid tie inverter energy stabilizing SEGMENTATION energy storage technology system interconnection
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A Preliminary Investigation of the Application of Modern Crustal Deformation Data in SeismicZonation
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作者 Zhou Bengang Zhou Qing 《Earthquake Research in China》 2006年第1期90-100,共11页
Using GPS observation data for the middle segment of the Fenwei seismic zone during the time period of 1996 ~ 2001, the velocity field of crustal movement is calculated. Thus, the vectors of relative horizontal movem... Using GPS observation data for the middle segment of the Fenwei seismic zone during the time period of 1996 ~ 2001, the velocity field of crustal movement is calculated. Thus, the vectors of relative horizontal movement between measuring points in the region are also obtained. Adopting a deformation model of homogeneous elastic body, the principal strain rate parameters of deformation units are calculated. A method is introduced to calculate the rate of seismic moment accumulation due to crustal deformation. The problems of using this rate to analyze the tendency of seismicity in the zone, and to estimate the recurrence interval of large earthquakes in the potential seismic source areas(PSSA) are discussed. The results show that the rate of seismic moment accumulation in the middle segment of the Fenwei zone is 4.22 x 1017 Nm/a, which is much higher than the average release rate of seismic moment in the current activity period. This means that the belt is now in a stage of seismic strain accumulation and that the seismicity would become stronger in the future than now. The results of estimation of the recurrence interval of large earthquakes in the Dingxiang and Huozhou PSSA are close to the results obtained from studying active faults. This implies that the use of the proposed estimation method is worthy of further investigation. In particular, it is of greater practical significance for those regions that have shorter history of earthquake records or lower degree of active structure study. 展开更多
关键词 Crustal deformation Seismic zonation Seismicity tendency Potential seismicsource area Application
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