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New multi-layer data correlation algorithm for multi-passive-sensor location system 被引量:1
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作者 Zhou Li Li Lingyun He You 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第4期667-672,共6页
Under the scenario of dense targets in clutter, a multi-layer optimal data correlation algorithm is proposed. This algorithm eliminates a large number of false location points from the assignment process by rough corr... Under the scenario of dense targets in clutter, a multi-layer optimal data correlation algorithm is proposed. This algorithm eliminates a large number of false location points from the assignment process by rough correlations before we calculate the correlation cost, so it avoids the operations for the target state estimate and the calculation of the correlation cost for the false correlation sets. In the meantime, with the elimination of these points in the rough correlation, the disturbance from the false correlations in the assignment process is decreased, so the data correlation accuracy is improved correspondingly. Complexity analyses of the new multi-layer optimal algorithm and the traditional optimal assignment algorithm are given. Simulation results show that the new algorithm is feasible and effective. 展开更多
关键词 multi-passive-sensor data correlation multi-layer correlation algorithm location system correlation cost
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A Multi-Objective Obnoxious Facility Location Modelon a Plane 被引量:1
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作者 U. K. Bhattacharya 《American Journal of Operations Research》 2011年第2期39-45,共7页
In this paper a Vertex Covering Obnoxious Facility Location model on a Plane has been designed with a combination of three interacting criteria as follows: 1) Minimize the overall importance of the various exist-ing f... In this paper a Vertex Covering Obnoxious Facility Location model on a Plane has been designed with a combination of three interacting criteria as follows: 1) Minimize the overall importance of the various exist-ing facility points;2) Maximize the minimum distance from the facility to be located to the existing facility points;3) Maximize the number of existing facility points covered. Area restriction concept has been incor-porated so that the facility to be located should be within certain restricted area. The model developed here is a class of maximal covering problem, that is covering maximum number of points where the facility is within the upper bounds of the corresponding mth feasible region Two types of compromise solution methods have been designed to get a satisfactory solution of the multi-objective problem. A transformed non- linear programming algorithm has been designed for the proposed non-linear model. Rectilinear dis-tance norm has been considered as the distance measure as it is more appropriate to various realistic situa-tions. A numerical example has been presented to illustrate the solution algorithm. 展开更多
关键词 Obnoxious Facility location multi-OBJECTIVE DECISION MAKING MAXIMAL COVERING Problem
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MLCPM-UC:一种基于模式实例分布均匀系数的多级co-location模式挖掘算法 被引量:4
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作者 刘新斌 王丽珍 周丽华 《计算机科学》 CSCD 北大核心 2021年第11期208-218,共11页
空间co-location(并置)模式是一组空间特征的子集,其实例在空间中频繁地邻近出现。由于空间数据同时存在关联性和异质性,co-location模式实例的分布或在整个研究区域中全局出现(全局co-location模式),或在研究区域的局部区域出现(区域co... 空间co-location(并置)模式是一组空间特征的子集,其实例在空间中频繁地邻近出现。由于空间数据同时存在关联性和异质性,co-location模式实例的分布或在整个研究区域中全局出现(全局co-location模式),或在研究区域的局部区域出现(区域co-location模式),从而提出了多级co-location模式挖掘。当前的多级co-location模式挖掘方法存在两个问题:1)已有的多级co-location模式挖掘方法忽略了模式在空间中的分布特性,未能准确区分全局和区域co-location模式;2)已有的多级模式挖掘方法将全局非频繁co-location模式作为候选区域co-location模式,导致候选区域co-location模式数量过多。针对以上问题,首先,定义了模式的实例分布均匀系数,在考虑模式频繁性的同时考虑了模式在空间中的分布情况,从而正确、高效地识别出全局和区域co-location模式。其次,基于模式的实例分布均匀系数,设计了一个有效的多级co-location模式挖掘算法,提出了有效的剪枝策略以提高算法效率。最后,在真实和合成数据集上进行了广泛的实验,验证了所提方法的正确性和高效性。 展开更多
关键词 空间数据挖掘 多级co-location模式 空间异质性 均匀系数
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Study on the method of optimal location on explosion events at near-source site 被引量:2
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作者 LI Xue-zheng 《Acta Seismologica Sinica(English Edition)》 CSCD 2001年第3期349-355,共7页
IntroductionEarthquake location is one of the inverse problems in seismology. The accurate earthquake source location is the basis of studies of earthquake images, the relation analysis between seismicity and tectonic... IntroductionEarthquake location is one of the inverse problems in seismology. The accurate earthquake source location is the basis of studies of earthquake images, the relation analysis between seismicity and tectonics, and the important parameters of earthquakes. It is also the basic data used to study the space distribution of aftershocks after a strong earthquake. The earthquake location accuracy mainly depends on reliability of the velocity models for the earth¢s crust, the reasonable design of the seismograph network, the accuracy of arrival time, and the location method used (ZHAO, 1983; ZHU, ZHAO, 1997; LI, et al, 1999). The reliability of the velocity model directly influences loca-tion results. The reasonable seismograph network design can improve the location accuracy; otherwise it will in-troduce ill-conditioned equations and large location error. If arrival time is not accurate, for example, if the seismic phase is wrongly identified or the time service is inaccurate, large arrival time error will be produced, and the location results and real hypocenters will be discordant. Different location algorithms adopted will produce differ-ent location errors. The residual criterion chosen has influence on location results. Besides, whether the event is correctly associated also influences the location quality. In practice, it can often be seen that large location devia-tion introduced by wrong event association. 展开更多
关键词 explosion EARTHQUAKES EARTHQUAKE location SIMPLEX PEDAL point on RADIAL line 文章编号:1000-9116(2001)02-0349-07
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The Application of GGE Biplot Analysis for Evaluating Test Locations and Mega-Environment Investigation of Cotton Regional Trials 被引量:15
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作者 XU Nai-yin Fok Michel +2 位作者 ZHANG Guo-wei LI Jian ZHOU Zhi-guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第9期1921-1933,共13页
In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to g... In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to governmental organizations in charge of cultivar registration. Where competition among breeding companies exists, effective and fair multi-environment variety trials are of utmost importance to motivate investment in breeding. The objective of this study was to use genotype main effect plus genotype by environment interaction(GGE) biplot analysis to evaluate test locations in terms of discrimination ability, representativeness and desirability, and to investigate the presence of multiple mega-environments in cotton production in the Yangtze River Valley(YaRV), China. Four traits(cotton lint yield, fiber length, lint breaking tenacity, micronaire) and two composite selection indices were considered. It was found that the assumption of a single mega-environment in the YaRV for cotton production does not hold. The YaRV consists of three cotton mega-environments: a main one represented by 11 locations and two minor ones represented by two test locations each. This demands that the strategy of cotton variety registration or recommendation must be adjusted. GGE biplot analysis has also led to the identification of test location superior for cotton variety evaluation. Although test location desirable for selecting different traits varied greatly, Jinzhou, Hubei Province, China, was found to be desirable for selecting for all traits considered while Jianyang, Sichuan Province, China, was found to be desirable for none. 展开更多
关键词 COTTON multi-environmental trial GGE biplot test location mega-environment
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Multilayer ANN indoor location system with area division in WLAN environment 被引量:4
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作者 Mu Zhou Yubin Xu Li Tang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第5期914-926,共13页
An indoor location system based on multilayer artificial neural network(ANN) with area division is proposed.The characteristics of recorded signal strength(RSS),or signal to noise ratio(SNR) from each available ... An indoor location system based on multilayer artificial neural network(ANN) with area division is proposed.The characteristics of recorded signal strength(RSS),or signal to noise ratio(SNR) from each available access points(APs),are utilized to establish the radio map in the off-line phase.And in the on-line phase,the two or three dimensional coordinates of mobile terminals(MTs) are estimated according to the similarity between the new recorded RSS or SNR and fingerprints pre-stored in radio map.Although the feed-forward ANN with three layers is sufficient to describe any nonlinear mapping relationship between inputs and outputs with finite discontinuous points,the efficient inputs for better training performances are difficult to be determined because of complex and dynamic indoor environment.Then,the discussion of distance relativity for different signal characteristics and optimal strategies for multi-mode phenomenon avoidance is presented.And also,the feasibility and effectiveness of this method are verified based on the experimental comparison with normal ANN without area division,K-nearest neighbor(KNN) and probability methods in typical office environment. 展开更多
关键词 indoor location artificial neural network multilayer structure multi-MODE relativity.
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Models for Location Inventory Routing Problem of Cold Chain Logistics with NSGA-Ⅱ Algorithm 被引量:1
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作者 郑建国 李康 伍大清 《Journal of Donghua University(English Edition)》 EI CAS 2017年第4期533-539,共7页
In this paper,a novel location inventory routing(LIR)model is proposed to solve cold chain logistics network problem under uncertain demand environment. The goal of the developed model is to optimize costs of location... In this paper,a novel location inventory routing(LIR)model is proposed to solve cold chain logistics network problem under uncertain demand environment. The goal of the developed model is to optimize costs of location,inventory and transportation.Due to the complex of LIR problem( LIRP), a multi-objective genetic algorithm(GA), non-dominated sorting in genetic algorithm Ⅱ( NSGA-Ⅱ) has been introduced. Its performance is tested over a real case for the proposed problems. Results indicate that NSGA-Ⅱ provides a competitive performance than GA,which demonstrates that the proposed model and multi-objective GA are considerably efficient to solve the problem. 展开更多
关键词 cold chain logistics multi-OBJECTIVE location inventory routing problem(LIRP) non-dominated sorting in genetic algorithm Ⅱ(NSGA-Ⅱ)
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Research on Location-Routing Problem with Empirical Analysis for Regional Logistics Distribution
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作者 Qian Zhang 《Applied Mathematics》 2014年第15期2305-2310,共6页
The location of the distribution facilities and the routing of the vehicles from these facilities are interdependent in many distribution systems. Such a concept recognizes the interdependence;attempts to integrate th... The location of the distribution facilities and the routing of the vehicles from these facilities are interdependent in many distribution systems. Such a concept recognizes the interdependence;attempts to integrate these two decisions have been limited. Multi-objective location-routing problem (MLRP) is combined with the facility location and the vehicle routing decision and satisfied the different objectives. Due to the problem complexity, simultaneous solution methods are limited, which are given in different objectives with conflicts in functions satisfied. Two kinds of optimal mathematical models are proposed for the solution of MLRP. Three methods have been emphatically developed for MLRP. MGA architecture makes it possible to search the solution space efficiently, which provides a path for searching the solution with two-objective LRP. At last the practical proof is given by random analysis for regional distribution with nine cities. 展开更多
关键词 DISTRIBUTION Facilities multi-OBJECTIVE location-Routing Problem (MLRP) MATHEMATICAL Models Random Analysis
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基于Multi-agent的智能馈线自动化自愈控制 被引量:17
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作者 高厚磊 庞清乐 +2 位作者 李尚振 亓延峰 王志涛 《高电压技术》 EI CAS CSCD 北大核心 2013年第5期1218-1224,共7页
针对传统馈线自动化自愈控制技术实时性差、互动性弱、可靠性低的问题,提出了基于Multi-agent系统的智能馈线自动化自愈控制方法。主站和每个智能配电终端均作为1个Agent,各Agent通过通信网络组成1个Multi-agent系统。各Agent通过信息交... 针对传统馈线自动化自愈控制技术实时性差、互动性弱、可靠性低的问题,提出了基于Multi-agent系统的智能馈线自动化自愈控制方法。主站和每个智能配电终端均作为1个Agent,各Agent通过通信网络组成1个Multi-agent系统。各Agent通过信息交互,利用改进的差动电流法实现故障定位,并利用启发式搜索算法,以停电负荷最少和馈线负荷均衡为故障恢复目标、以供电恢复路径的负荷度最小为搜索规则,实现故障恢复。通过电磁暂态仿真软件PSCAD对某实际配电网进行仿真,利用改进的差动电流法,中间支路和边界支路均能实现准确地故障定位;利用启发式搜索方法,能实现非故障失电区全部负荷的供电恢复,故障恢复效果与传统的遗传算法相当,但是故障恢复时间明显缩短且满足负荷均衡。仿真结果表明,该自愈控制方法能够实现准确地故障定位和快速地故障恢复,可以可靠地应用于智能配电网。 展开更多
关键词 智能配电网 智能馈线自动化 自愈 多智能体 故障定位 故障恢复
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基于Multi-index LQ与CIC指数的集成评估框架 被引量:3
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作者 张志明 曹钰 《合肥工业大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第5期716-719,共4页
将多指标区位商计算和工业集群竞争力评价相结合,生成集成的工业集群竞争力评估框架,运用统计数据,可对我国区域工业集群现状及工业集群竞争力水平进行分析。结果表明,区域工业经济存在4种类型,即集聚的竞争优势产业、集聚的竞争劣势产... 将多指标区位商计算和工业集群竞争力评价相结合,生成集成的工业集群竞争力评估框架,运用统计数据,可对我国区域工业集群现状及工业集群竞争力水平进行分析。结果表明,区域工业经济存在4种类型,即集聚的竞争优势产业、集聚的竞争劣势产业、非集聚的竞争优势产业和非集聚的竞争劣势产业;据此,我国区域工业经济的支柱产业和主导产业可以被确定。 展开更多
关键词 工业集群 多指标区位商 工业集群竞争力 集成评估框架
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基于BA-MKELM的微电网故障识别与定位 被引量:1
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作者 吴忠强 卢雪琴 《计量学报》 CSCD 北大核心 2024年第2期253-260,共8页
提出一种基于贝叶斯算法优化多核极限学习机的微电网故障识别和定位方法。针对极限学习机输入参数和隐含层节点数随机选取导致回归能力不足的问题,引入核函数,将多项式与高斯径向基核函数加权组合构成多核极限学习机建立故障识别与定位... 提出一种基于贝叶斯算法优化多核极限学习机的微电网故障识别和定位方法。针对极限学习机输入参数和隐含层节点数随机选取导致回归能力不足的问题,引入核函数,将多项式与高斯径向基核函数加权组合构成多核极限学习机建立故障识别与定位模型,并采用贝叶斯算法对多核极限学习机相关参数进行优化,进一步提高模型的逼近能力。为了验证所提模型的故障识别与定位性能,选用极限学习机和多核极限学习机分别建立故障诊断模型进行比较分析。实验结果表明,所提方法能够高性能地识别和定位微电网中任何类型的故障,识别和定位精度更高。 展开更多
关键词 电学计量 微电网线路 故障识别和定位 贝叶斯算法 多核极限学习机 小波包分解
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Multi-features Based Approach for Moving Shadow Detection 被引量:4
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作者 周宁 周曼丽 +1 位作者 许毅平 方宝红 《Journal of Donghua University(English Edition)》 EI CAS 2004年第6期76-80,共5页
In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving... In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence. 展开更多
关键词 MOVING SHADOW detection multi - features MOVING OBJECT DETECTION
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:42
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作者 Xiang-Qun Cui Yong-Heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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Comparison of two earthquake early warning location methods 被引量:1
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作者 Jun Li Xing Jin +1 位作者 Hongcai Zhang Yongxiang Wei 《Earthquake Science》 2013年第1期15-22,共8页
According to earthquake catalog records of Fujian Seismic Network, the Tnow method and the fourstation continuous location method put forward by Jin Xing are inspected by using P-wave arrival information of the first ... According to earthquake catalog records of Fujian Seismic Network, the Tnow method and the fourstation continuous location method put forward by Jin Xing are inspected by using P-wave arrival information of the first four stations in each earthquake. It shows that the fourstation continuous location method can locate more seismic events than the Tnow method. By analyzing the results, it is concluded that the reason for this is that the Tnow method makes use of information from stations without being triggered, while some stations failed to be reflected in earthquake catalog because of discontinuous records or unclear records of seismic phases. For seismic events whose location results can be given, there is no obvious difference in location results of the two methods and positioning deviation of most seismic events is also not significant. For earthquakes outside the network, the positioning deviation may amplify as the epicentral distance enlarges, which may relate to the situation that the seismic stations are centered on one side of epicenter and the opening angle between seismic stations used for location and epicenter is small. 展开更多
关键词 Earthquake early warning - Tnowlocation method Earthquake catalog Four-stationcontinuous location method
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Location Data Fusion Based on Group Consensus
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作者 李国栋 陈维南 《Journal of Southeast University(English Edition)》 EI CAS 1997年第1期98-102,共5页
A new method of multi sensor location data fusion is proposed.The method is based on group consensus approach, which constructs group utility function (or its density) based on uncertainty of each sensor, and the loc... A new method of multi sensor location data fusion is proposed.The method is based on group consensus approach, which constructs group utility function (or its density) based on uncertainty of each sensor, and the location estimation is obtained based on the group utility function (or its density). The simulation results show that the method is better than those of mean and median estimation, and outlier and sensor failure can not affect the location estimation. 展开更多
关键词 multi sensor DATA FUSION UTILITY function GROUP CONSENSUS location DATA FUSION
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A Comparative Study of Acute Hemodynamic Effects of Multi -site Cardiac Pacing in patients with cardiac function NYHA class ⅠtoⅡ without bundle branch block 被引量:2
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作者 朱参战 崔长琮 +5 位作者 张全发 薛小临 刘维维 刘引会 《South China Journal of Cardiology》 CAS 2001年第2期101-105,共5页
Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS ... Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS 7, Ⅲ°AVB 5) undergoing pacemaker implantation. Right ventricular apex (RVA), right ventricular outflow tract (RVOT), right ventricular bifocal (RV-Bi), left ventricular base (LVB) and bi -ventricular (Bi-Ⅴ) pacing at 60 -80 ppm were done in VVI mode prior to implantation of DDD pacemaker. The cardiac index (CI), mean pulmonary artery pressure (mPAP) and pulmonary capillary wedge pressure (PCWP) were measured with Swan - Ganz thermodilution catheter after 5 minutes of each pacing mode. Results (1) Comparing to pacing at RVA (CI: 2. 41± 0. 38 L/min per m2, PCWP: 16. 7 ±3.3 mmHg), the CI increased and the PCWP decreased significantly in pacing at RVOT(CI: 2. 63 ± 0.46, PCWP: 13. 8±2. 3), LVB(CI: 2. 78±0.52, PCWP: 14. 4±3.1), RV-Bi(CI: 2. 83±0.57, PCWP: 12. 8± 2. 5) and Bi -Ⅴ pacing (CI: 2. 94± 0.60, PCWP: 12. 7±2. 5), P < 0. 01, respectively. (2) The CI of RV-Bi and Bi-Ⅴ pacing was higher than that of RVOT and LVB pacing, the PCWP was lower, P < 0. 05, respectively. (3) There was no significant difference between RV - Bi pacing and Bi-Ⅴ pacing in CI and PCWP. Conclusion There is no significant difference between RV - Bi pacing and Bi -V pacing in the acute hemodynamic effects; however,dual - site pacing is much better than single site pacing in that aspect for patients with cardiac function NYHA class Ⅰ to Ⅱ without BBB. Among single site pacing, the RVOT and LVB pacing is better than RVA pacing in cardiac function. 展开更多
关键词 multi - site cardiac pacingHemodynamics
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MODELS OF THE SPATIAL EVOLUTION OF MULTI-PLANT ENTERPRISES 被引量:1
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作者 费洪平 《Chinese Geographical Science》 SCIE CSCD 1994年第2期134-147,共14页
Since the 1970s, the studies on the geography of enterprise have become increasingly concerned with the spatial evolution of an enterprises in the West developed countries. However, little attention has so far been g... Since the 1970s, the studies on the geography of enterprise have become increasingly concerned with the spatial evolution of an enterprises in the West developed countries. However, little attention has so far been given to the spatial evolution of an enterprise in China. With China's ongoing economy and political reforms, a number of fundamental changes of enterprise behavior have occurred. These changes have certainly important influences on the evolution of industrial location. Therefore, there is a need for examining the spatial evolution of an enterprise in China. The purpose of the paper is to review the mapjor models of both the growth,and associated spatial evolution of an enterprise, with an illustrative case study of the HeaVy Automobile Enterprise Group of China. The paper is organized by three parts. The first examines the spoilal groWth and location adjustment of multi-plant enterprise. The second reviews mapjor models of the spatial evolution of an enterprise. And the third analyzes the spatial evolution, over a period of time, of a representative sample of the Heavy Automobile Enterprise Group of China, and illustrates the findings with case studies. It is suggested that the models of spatial evolution of an enterprise would provide more evidence about micro-mechanism for evolution of micro- regional economic systems. 展开更多
关键词 multi-plant ENTERPRISES ENTERPRISE GROUPS SPATIAL evolution of an ENTERPRISE SPATIAL growth location adjustment
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LOCATIONAL DISTRIBUTION AND SPATIAL DIFFUSION OF FOREIGN DIRECT INVESTMENTS FROM HONGKONG AND MACAO IN MAINLAND OF CHINA
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作者 贺灿飞 陈颖 周颖 《Chinese Geographical Science》 SCIE CSCD 1997年第4期328-338,共11页
Foreign direct investments (or FDIs) have been employed since the early 1980s and they have become more and more immportant in Chinese economic development. However, the roles of FDIs are very different between region... Foreign direct investments (or FDIs) have been employed since the early 1980s and they have become more and more immportant in Chinese economic development. However, the roles of FDIs are very different between regions, partly due to the different locational preference of various source countries. Some facts show that FDIs from Hongkong - Macao indicate a strong locational preference. Therefore, this paper attempts to make an empirical research on the locational preference of Hongkong - Macao’s FDIs and their spatial diffusion under the support of statistical data with regrereion analysis. In this paper, three statistical models, including the special location model, the general location model and the spatial diffusion model, are created. The results show that this kind of analysis is successful. The major conclusions are as follows. (1) The optimum location for FDIs from Hongkong - Macao lies in the coastal area, especially Guangdong, Hainan, Jiangsu, Shandong, Fujian provinces. Besides, Hubei Province is also an important radon. (2) The FDIs from HongkongMacao in China have diffused gradually from the coastal provinces to the inland regions, the northem and the metropolis and from the locations that had attracted a large number of investments to their vicinities since the 1990s. (3) The special location factors, such as the herder effect, the unique social and kinship ties are the key factors determining the special locational distribution. (4) The general location and spatial diffusion of Hongkong - Macao’s FDIs are the results of interplay of several economic factors. They are the economic scale and advantage, the growth rate, the laier force and economic extrovert etc. 展开更多
关键词 HONGKONG - MACAO FOREIGN direct INVESTMENTS (or FDIs) location model
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基于语义一致性约束与局部-全局感知的多模态3D视觉定位
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作者 罗寒 马浩统 +2 位作者 刘杰 严华 雷印杰 《计算机应用研究》 CSCD 北大核心 2024年第7期2203-2208,共6页
3D多模态数据稀缺,使得传统方法进行监督训练时文本与视觉特征缺乏语义一致性。同时传统方法还易忽视局部关系与全局信息,从而导致性能不佳。针对上述问题,提出了一种基于语义一致性约束与局部-全局感知的多模态3D视觉定位方法。首先,... 3D多模态数据稀缺,使得传统方法进行监督训练时文本与视觉特征缺乏语义一致性。同时传统方法还易忽视局部关系与全局信息,从而导致性能不佳。针对上述问题,提出了一种基于语义一致性约束与局部-全局感知的多模态3D视觉定位方法。首先,该方法通过蒸馏2D预训练视觉语言模型知识,帮助3D模型提取到点云-文本语义一致性特征;其次设计了局部-全局感知模块,不断补充增强候选目标特征,以更精确匹配目标。在现有的3D视觉定位数据集ScanRefer上进行的实验表明,该方法在Acc@0.25 IoU和Acc@0.5 IoU两个指标上分别达到了50.53%和37.67%,超越了现有大多数3D视觉定位算法,证实了该方法的有效性。 展开更多
关键词 3D视觉定位 多模态 特征一致性约束 局部关系 全局位置信息
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Optimal setting and placement of FACTS devices using strength Pareto multi-objective evolutionary algorithm 被引量:2
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作者 Amin Safari Hossein Shayeghi Mojtaba Bagheri 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期829-839,共11页
This work proposes a novel approach for multi-type optimal placement of flexible AC transmission system(FACTS) devices so as to optimize multi-objective voltage stability problem. The current study discusses a way for... This work proposes a novel approach for multi-type optimal placement of flexible AC transmission system(FACTS) devices so as to optimize multi-objective voltage stability problem. The current study discusses a way for locating and setting of thyristor controlled series capacitor(TCSC) and static var compensator(SVC) using the multi-objective optimization approach named strength pareto multi-objective evolutionary algorithm(SPMOEA). Maximization of the static voltage stability margin(SVSM) and minimizations of real power losses(RPL) and load voltage deviation(LVD) are taken as the goals or three objective functions, when optimally locating multi-type FACTS devices. The performance and effectiveness of the proposed approach has been validated by the simulation results of the IEEE 30-bus and IEEE 118-bus test systems. The proposed approach is compared with non-dominated sorting particle swarm optimization(NSPSO) algorithm. This comparison confirms the usefulness of the multi-objective proposed technique that makes it promising for determination of combinatorial problems of FACTS devices location and setting in large scale power systems. 展开更多
关键词 STRENGTH PARETO multi-objective evolutionary algorithm STATIC var COMPENSATOR (SVC) THYRISTOR controlled series capacitor (TCSC) STATIC voltage stability margin optimal location
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