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Precise Location of Earthquakes at the Eastern Boundaries of the Sichuan-Yunnan Rhombic Block
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作者 Fu Ying Hu Bin +1 位作者 Long Feng Wang Shiyuan 《Earthquake Research in China》 CSCD 2018年第4期470-481,共12页
Based on the seismic station data sets from Sichuan and Yunnan provinces,we employed a multi-step seismic location method( Hypo2000 + Velest + HypoDD) to precisely locate the 7,787 earthquakes that occurred during 201... Based on the seismic station data sets from Sichuan and Yunnan provinces,we employed a multi-step seismic location method( Hypo2000 + Velest + HypoDD) to precisely locate the 7,787 earthquakes that occurred during 2010-2015 along the eastern boundaries of the Sichuan-Yunnan rhombic block,namely from southern Dawu to the Qiaojia segment.The final results show that location precision is greatly advanced and epicenter distribution exhibits good consistency with the linear distribution of the seismic faults. Earthquake distribution is quite intensive at the intersection region in the southern segment of the Xianshuihe fault,the Anninghe fault zone,the Xiaojinhe fault zone and the Daliangshan fault zone to the east. The depth profile of seismicity shows a clear stepwise activity along the active seismic fault zones. The profile crossing the faults of the Xianshuihe,Anninghe,and Daliangshan presents a complex interaction among faults near the multiple faults intersection region,Shimian,where the earthquakes are obviously divided into two groups in depth. Earthquakes are very rare at the depth of 15km-20 km,which is consistent with the region of the plastic rheology between 14km-19 km calculated by Zhu Ailan et al.,( 2005). 展开更多
关键词 EASTERN boundaries of Sichuan-Yunnan rhombic BLOCK precise location Hypo2000 HypoDD
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Study on Precise Location and Structure of Earthquakes in the Shanxi Reservoir,Zhejiang Province
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作者 Zhu Xinyun Zhang Fan Yu Junyi 《Earthquake Research in China》 2011年第4期456-467,共12页
The Shanxi reservoir earthquakes are significant seismic events in southern Zhejiang Province in recent years, an area with fewer and weaker earthquakes. The seismicity showed an intermittent characteristic and group ... The Shanxi reservoir earthquakes are significant seismic events in southern Zhejiang Province in recent years, an area with fewer and weaker earthquakes. The seismicity showed an intermittent characteristic and group distribution. The epicenters located by the seismic network did not show a predominant direction and the seismogenic structure is not clear. In the study, the nonlinear imaginary wave travel time equation was linearized and solved, and the source position, initial imaginary velocity and travel time residuals were obtained. Then by doubling the standard deviation as time residuals, the maximum error generated from longitude, latitude, depth and imaginary velocity was calculated. The genetic population was structured using the maximum error and the end result of earthquake location was obtained by genetic algorithm. The result of relocation of the Shanxi reservoir earthquakes with this method shows that earthquakes are largely concentrated on a near-vertical, northwest oriented fault plane, and the included angles between the normal of the plane and the due north, due east and vertical directions are 46~, 44~, and 87~, respectively. The result is in agreement with that of comprehensive fault plane solutions of small earthquakes. The average depth of the earthquakes was 4.7km, the maximum depth 9.5kin, and the minimum depth 1.7km. The epicenters showed a northwestward narrow banded distribution, and the focal depth increased along the northwest direction. There was a discontinuous seismic gap of about 3.5km long at the northwest end of the strip. The characteristics of source parameters obtained by using the Borun model were not significantly different from that of tectonic earthquakes. Seismic stress drop was about 0.33MPa, and the average stress drop was 0.88MPa. According to the stress drop' spatial distribution, the seismic discontinuities segment at the northwest end of the strip is in a low stress drop zone. 展开更多
关键词 Reservoir induced earthquake Genetic algorithm precise location Faultplane Stress drop
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3-D Lightning Location Solution and Precision Analysis of Cloud Flash 被引量:5
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作者 ZHANG Ping ZHAO Wenguang +1 位作者 HU Zhixiang WEN Yinping 《Wuhan University Journal of Natural Sciences》 CAS 2009年第3期241-244,共4页
Using the spatial coordinates of detection stations and the time of arrival of lightning wave,the observation equations can be expressed.For the large lightning detection network,the least square method is used to pro... Using the spatial coordinates of detection stations and the time of arrival of lightning wave,the observation equations can be expressed.For the large lightning detection network,the least square method is used to process the adjustment of observation data to find the most probable value of lightning position,and the result is assessed by the mean error and dilution of precision.Lightning location precision is affected by figure factor.The conclusion can be used in the design of location network,data processing,and data analysis. 展开更多
关键词 3-D lightning location cloud flash detection solution model dilution of precision figure factor
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Application of micro-seismic monitoring technology in mining engineering 被引量:11
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作者 Sun lian Wang Lianguo Hou Huaqiang 《International Journal of Mining Science and Technology》 2012年第1期79-83,共5页
Micro-seismic phenomena, occurring when rock masses are subjected to forces and failures, allow the determination of their unstable states and failure zones by analyzing micro-seismic signals. We first present the pri... Micro-seismic phenomena, occurring when rock masses are subjected to forces and failures, allow the determination of their unstable states and failure zones by analyzing micro-seismic signals. We first present the principles of micro-seismic monitoring and location, as well as an underground explosion-proof micro-seismic monitoring system. Given a practical engineering application, we describe the application of micro-seismic monitoring technology in determining the height of a "two-zone" overburden, i.e., a caving zone and a fracture zone, the width of a coal-pillar section and the depth of failure of a floor. The workfaces monitored accomplished safe and highly efficient mining based on our micro-seismic monitoring results and provide direct proof of the reliability and validity of micro-seismic monitoring technology. 展开更多
关键词 micro-seismic phenomenon micro-seismic monitoring micro-seismic location Mining engineering
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Three dimensional velocity structure and accurate earthquake location in Changning–Gongxian area of southeast Sichuan 被引量:21
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作者 Feng Long ZhiWei Zhang +5 位作者 YuPing Qi MingJian Liang Xiang Ruan WeiWei Wu GuoMao Jiang LongQuan Zhou 《Earth and Planetary Physics》 CSCD 2020年第2期163-177,共15页
In order to understand the crustal structure and tectonic background of the Changning–Gongxiang area, southeastern Sichuan Province, where a series of moderate-to-strong earthquakes occurred in recent years, we utili... In order to understand the crustal structure and tectonic background of the Changning–Gongxiang area, southeastern Sichuan Province, where a series of moderate-to-strong earthquakes occurred in recent years, we utilized the seismic phase data both from a local dense array and from the regional seismic networks;we used the tomoDD program to invert for the high-resolution three-dimensional velocity structure within the depth range of 0–10 km and for accurate hypocentral locations in this area. We analyzed the seismogenic structures for the events of Xingwen M5.7 in 2018 and Gongxian M5.3 and Changning M6.0 in 2019. The results show that:(1) widespread lateral inhomogeneity exists in the velocity structure of the study area, and the location of the velocity anomaly is largely consistent with known structures. In the range of distinguishable depth, the inhomogeneity decreases with increasing depth, and the velocity structure anomalies in some areas are continuous in depth;(2) earthquakes occurred in clusters, showing the characteristics of zonal folding trends in the NW-SE and NE-SW directions;the focal depth in the area is generally shallow in both the sedimentary cap and the crystalline basement. The seismogenic structures of small earthquake clusters are different in size and occurrence in different sections, and the clusters occurred mostly in regions with high P-or S-wave velocities;(3) synthesis of a variety of data suggests that the seismogenic structures of the Xingwen M5.7 and Changning M6.0 earthquakes are associated with slip faults that trend NW-SE in, respectively, the south wing and the axis of the Changning–Shuanghe anticline, while that of the Gongxian M5.3 earthquake is associated with thrust faults that trend N-S in the Jianwu syncline region. The dynamic sources of the three earthquakes are all from the SE pushing of the Qinghai–Tibet block on the Sichuan basin;(4) the risk of future strong earthquakes in this area must be reevaluated in light of the facts(a)that in recent years, moderate-to-strong earthquake swarms have occurred frequently in southeast Sichuan;(b) that the complex structural area exhibits the easy-to-trigger characteristic, and(c) that the small-scale faults in this area are characterized by the phenomenon of stress "lock and release". 展开更多
关键词 southeastern Sichuan Sichuan Basin three-dimensional velocity structure earthquake precise location
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Precise Modulation Strategies for Transcranial Magnetic Stimulation:Advances and Future Directions 被引量:10
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作者 Gangliang Zhong Zhengyi Yang Tianzi Jiang 《Neuroscience Bulletin》 SCIE CAS CSCD 2021年第12期1718-1734,共17页
Transcranial magnetic stimulation(TMS)is a popular modulatory technique for the noninvasive diagnosis and therapy of neurological and psychiatric diseases.Unfortunately,current modulation strategies are only modestly ... Transcranial magnetic stimulation(TMS)is a popular modulatory technique for the noninvasive diagnosis and therapy of neurological and psychiatric diseases.Unfortunately,current modulation strategies are only modestly effective.The literature provides strong evidence that the modulatory effects of TMS vary depending on device components and stimulation protocols.These differential effects are important when designing precise modulatory strategies for clinical or research applications.Developments in TMS have been accompanied by advances in combining TMS with neuroimaging techniques,including electroencephalography,functional nearinfrared spectroscopy,functional magnetic resonance imaging,and positron emission tomography.Such studies appear particularly promising as they may not only allow us to probe affected brain areas during TMS but also seem to predict underlying research directions that may enable us to precisely target and remodel impaired cortices or circuits.However,few precise modulation strategies are available,and the long-term safety and efficacy of these strategies need to be confirmed.Here,we review the literature on possible technologies for precise modulation to highlight progress along with limitations with the goal of suggesting future directions for this field. 展开更多
关键词 Transcranial magnetic stimulation Modulation strategies precise stimulation target Coil location Individual treatment paradigm
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A Novel Adaptive Cooperative Location Algorithm for Wireless Sensor Networks 被引量:4
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作者 Wen-Jiang Feng Xiao-Wei Bi Rong Jiang 《International Journal of Automation and computing》 EI 2012年第5期539-544,共6页
To overcome the disadvantages of the location algorithm based on received signal strength indication(RSSI)in the existing wireless sensor networks(WSNs),a novel adaptive cooperative location algorithm is proposed.To t... To overcome the disadvantages of the location algorithm based on received signal strength indication(RSSI)in the existing wireless sensor networks(WSNs),a novel adaptive cooperative location algorithm is proposed.To tolerate some minor errors in the information of node position,a reference anchor node is employed.On the other hand,Dixon method is used to remove the outliers of RSSI,the standard deviation threshold of RSSI and the learning model are put forward to reduce the ranging error of RSSI and improve the positioning precision effectively.Simulations are run to evaluate the performance of the algorithm.The results show that the proposed algorithm offers more precise location and better stability and robustness. 展开更多
关键词 Wireless sensor networks(WSNs) adaptive cooperative location positioning precision received signal strength indication(RSSI) Dixon method
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Study on Location of Wuhan Steel Logistics Distribution Center 被引量:2
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作者 Mengyue Yang Zhenping Li 《Open Journal of Applied Sciences》 2016年第13期938-943,共7页
This paper studies the location of Wuhan steel logistics distribution center. First of all, according to Wuhan Iron and Steel Plant sales in Hunan Province and the relative position of the city, the transport costs ar... This paper studies the location of Wuhan steel logistics distribution center. First of all, according to Wuhan Iron and Steel Plant sales in Hunan Province and the relative position of the city, the transport costs are calculated from Wuhan Iron and Steel Plant to the demand point. We further analyze the necessity of establishing steel logistics distribution center, using the precise center of gravity to determine the actual location of the distribution center. After the establishment of distribution center, the total freight is reduced by 15.46 million yuan from Wuhan Iron and Steel Plant to each city in Hunan province via distribution center each year. The results of this paper can provide theoretical basis for the logistics node planning of related enterprises. 展开更多
关键词 Steel Logistics Distribution Center location precise Center of Gravity Method
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Subpixel Target Location Techniques for 3-D Coordinate Measuring System
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作者 YUZhi-jing MASu-ying 《Semiconductor Photonics and Technology》 CAS 2002年第2期111-115,共5页
the close photogrammetric 3-D coordinate measurement is a newmeasuring technology in the fields of the coordinate measurementmachine (CMM) in recent years. In this method, we usually place sometargets on the measured ... the close photogrammetric 3-D coordinate measurement is a newmeasuring technology in the fields of the coordinate measurementmachine (CMM) in recent years. In this method, we usually place sometargets on the measured object and take image of targets to determinethe object coordinate. The subpixel location of target image plays animportant role in high accuracy 3-D coordinate measuring procedure.In this paper, some subpixel location methods are reviewed and somefactors which affect location precision are analyzed. 展开更多
关键词 Subpixel precision target location centroid algorithm bilinearinterpolation
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基于距离和―测向交汇定位的三坐标外辐射源定位精度分析
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作者 马献德 许磊 +2 位作者 朱旭东 张南根 朱光华 《现代雷达》 北大核心 2026年第3期73-79,共7页
针对采用目标距离和―测向交汇定位原理的外辐射源雷达,根据目标距离和及目标方位测量方程,通过一种基于误差协方差的分析框架,推导了两坐标情况下目标定位精度的解析形式,将其直接表达为目标位置、距离和测量精度、方位测量精度及收发... 针对采用目标距离和―测向交汇定位原理的外辐射源雷达,根据目标距离和及目标方位测量方程,通过一种基于误差协方差的分析框架,推导了两坐标情况下目标定位精度的解析形式,将其直接表达为目标位置、距离和测量精度、方位测量精度及收发站址测量精度的函数。采用相同的方法,增加了目标俯仰测量方程,推导得到了三坐标情况下目标定位精度的解析形式,并在此基础上,从理论上分析了两坐标、三坐标情况下目标定位精度空间分布的典型特征。在三坐标外辐射源雷达“空发地收”“天发地收”等应用场景下,设置典型仿真参数,并进行了仿真实验。在典型场景下定位精度几何分布的仿真结果与理论分析相吻合,验证了所提分析方法及目标定位精度解析结果的有效性。 展开更多
关键词 三坐标 距离和―测向交汇定位 外辐射源雷达 精度几何分布 解析形式
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基于共位置模式挖掘算法的疾病传播空间节点识别方法及应用
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作者 陈默然 任红艳 逯伟利 《地球信息科学学报》 北大核心 2026年第3期772-784,共13页
【目的】高发频发的传染病疫情对高度城市化地区现有的传染病防控体系形成重要挑战。为提升城市地区的传染病精准防控能力,本文构建了一套面向城市内部传染病传播流行空间节点的识别方法。【方法】本文基于经典的共位置模式挖掘算法,通... 【目的】高发频发的传染病疫情对高度城市化地区现有的传染病防控体系形成重要挑战。为提升城市地区的传染病精准防控能力,本文构建了一套面向城市内部传染病传播流行空间节点的识别方法。【方法】本文基于经典的共位置模式挖掘算法,通过调整空间邻近阈值确定方式、优化搜索策略以及引入蒙特卡洛模拟方法等改进,形成了面向城市地区传染病传播流行的典型城市场所识别方法。通过广州市2017—2019年登革热传播流行空间节点识别的实例验证,计算参与指数(Participation Index, PI)以度量传染病病例与城市场所之间的共位置关系,并对其进行0.05水平上的显著性检验;在此基础上,从空间节点数量、空间邻近距离、病例密度等角度对比分析了广州市登革热传播流行空间节点的识别效果。【结果】基于蒙特卡洛模拟方法的显著性检验可以有效剔除一些与登革热病例虚假空间关联的城市场所;相较于统一阈值策略,采用K-D树搜索的自适应阈值确定策略能够识别出更多的空间节点,这些节点与病例之间的空间邻近距离更符合实际情况。同时,报刊亭(0.22<PI<0.73)、疗养场所(0.41<PI<0.61)等空间节点附近区域的登革热流行强度(病例密度)明显高于区域平均水平及非节点附近水平。此外,2017—2019年登革热在广州市传播流行的空间节点呈现较为明显的区域、年际差异,且空间节点的识别结果与病例的年龄、职业特征关系密切。【结论】基于共位置模式挖掘算法的城市疾病传播流行空间节点的识别方法,能够在城市的复杂环境与人群中准确识别影响传染病传播流行的关键城市场所,具有较好的应用效果。本研究有助于加深对城市传染病传播流行过程的理解,将为登革热等传染病的精准防控提供方法支撑。 展开更多
关键词 共位置模式挖掘 蒙特卡洛模拟 疾病传播 空间节点 精准防控 登革热
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MRI在经颅磁刺激靶点精准定位中的应用进展
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作者 韩羽 丁婷婷 +1 位作者 冯子健 臧玉峰(审校) 《国际医学放射学杂志》 2026年第1期64-67,共4页
经颅磁刺激是一种无创的物理治疗技术,对多种神经系统疾病有明确的疗效,但疗效的个体差异大,精准定位个体化刺激靶点是提升疗效的关键。结构MRI能够引导经颅磁刺激,解决部分个体脑结构差异的问题。功能MRI(fMRI)可以确定脑功能与异常脑... 经颅磁刺激是一种无创的物理治疗技术,对多种神经系统疾病有明确的疗效,但疗效的个体差异大,精准定位个体化刺激靶点是提升疗效的关键。结构MRI能够引导经颅磁刺激,解决部分个体脑结构差异的问题。功能MRI(fMRI)可以确定脑功能与异常脑活动的个体化坐标,能够为经颅磁刺激提供个体化刺激靶点;静息态fMRI功能连接则被认为可以提供“桥梁”,使得磁刺激从脑表面皮质传递到深部效应靶点。本文就MRI在精准定位经颅磁刺激治疗方面的进展进行综述。 展开更多
关键词 磁共振成像 经颅磁刺激 精准定位 功能连接 局部脑活动
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多站测向交叉定位的定位精度研究
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作者 曹文焕 韩升明 陈超 《现代电子技术》 北大核心 2026年第5期51-55,共5页
对敌方雷达进行定位可以获取雷达位置,进而引导干扰和反辐射攻击,为获取电磁战场优势提供了先决条件。通常,采用无源定位的方式获取雷达位置,其中测向交叉定位法环境适应性好、所需设备量适中,是雷达无源定位中最广泛应用的方法。然而,... 对敌方雷达进行定位可以获取雷达位置,进而引导干扰和反辐射攻击,为获取电磁战场优势提供了先决条件。通常,采用无源定位的方式获取雷达位置,其中测向交叉定位法环境适应性好、所需设备量适中,是雷达无源定位中最广泛应用的方法。然而,多站测向交叉定位存在定位模糊区,模糊区越小,定位精度越高。为了分析定位精度,在定位原理的基础上,提出一种几何稀释度的精度计算方法。通过分析几何稀释度的计算公式,定位误差的影响因素包括测向误差、侦察站位置、侦察站数量和布站方式。仿真实验结果表明,提高测向精度、侦察站靠近目标、合理布站以及增加侦察站数量这四条措施可以有效提高定位精度。在实际应用中,可根据需要采取相应的措施来提高测向交叉定位的定位精度,从而得到更为精确的雷达目标位置信息,该方法具有一定的实用价值。 展开更多
关键词 测向交叉定位 定位精度 几何稀释度 测向精度 无源定位 布站方式
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The precise regulation of noble metal-loaded layered double hydroxides nanocatalysts:synthesis and structure-activity relationship
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作者 Ziheng Song Zhaohui Wu +5 位作者 Yihang Hu Yimo Wang Yuhao Zheng Siyu Hu Jinfeng Chu Yu-Fei Song 《Science China Chemistry》 2026年第1期73-93,共21页
The deliberate and precise fabrication of supported catalysts with well-defined structures has been a long-standing pursuit.Among the large number of supports for anchoring noble metal species,layered double hydroxide... The deliberate and precise fabrication of supported catalysts with well-defined structures has been a long-standing pursuit.Among the large number of supports for anchoring noble metal species,layered double hydroxides(LDHs)stand out as a class of ideal supports for dispersing noble metal species due to their uniform distribution of metal sites and charge centers.However,a prerequisite for the investigation of noble metals-loaded LDHs is the construction of well-defined active sites and precisely controlled sizes of noble metal species on LDH surfaces.Based on research advances made over the past decade,we provide a detailed discussion on the fine regulation of noble metal species,including single atoms,nanoclusters,nanoparticles,and multi-site catalysts on LDHs.Furthermore,we focus on uncovering three critical aspects of noble metal-loaded LDHs:the precise location,the atomic configurations,and the interaction with the LDHs.Building upon these well-defined structures,we further clarify the structure-activity relationships of the developed materials in reactions such as hydrazine decomposition,biomass conversion,C–H bond activation,and water splitting,etc.Finally,the challenges and future directions are outlined to offer valuable insights for advancing high-activity noble metal-loaded LDHs. 展开更多
关键词 layered double hydroxides noble metals precise location atomic configuration structure-activity relationship
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基于5G的低压线路故障精准定位技术研究
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作者 王新建 徐文广 《通信电源技术》 2026年第3期243-245,共3页
针对低压配电线路故障类型繁杂、测点分布零散、定位精度欠佳的问题,提出一种基于5G的低压线路故障精准定位技术。该技术基于多节点故障特征数据采集,依靠5G实现故障数据的实时传输以及高精度时间同步,构建起由同步数据驱动的故障定位... 针对低压配电线路故障类型繁杂、测点分布零散、定位精度欠佳的问题,提出一种基于5G的低压线路故障精准定位技术。该技术基于多节点故障特征数据采集,依靠5G实现故障数据的实时传输以及高精度时间同步,构建起由同步数据驱动的故障定位计算方法。工程验证结果表明,该方法能够有效缩短故障定位响应时间,提升低压线路故障定位精度,具有一定工程应用价值。 展开更多
关键词 5G 低压线路 故障精准定位
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Precision interventional radiology 被引量:2
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作者 Jiansong Ji Shiji Fang +4 位作者 Minjiang chen Liyun zheng Weiqian Chen Zhongwei Zhao Yongde Cheng 《Journal of Interventional Medicine》 2021年第4期155-158,共4页
The recent interest in precision medicine among interventionists has led to the establishment of the concept of precision interventional radiology(PIR).This concept focuses not only on the accuracy of interventional o... The recent interest in precision medicine among interventionists has led to the establishment of the concept of precision interventional radiology(PIR).This concept focuses not only on the accuracy of interventional operations using traditional image-guided techniques,but also on the comprehensive evaluation of diseases.The invisible features extracted from CT,MRI,or US improve the accuracy and specificity of diagnosis.The integration of multi-omics and molecule imaging provides more information for interventional operations.The development and application of drugs,embolic materials,and devices broaden the concept of PIR.Integrating medicine and engineering brings new image-guided techniques that increase the efficacy of interventional operations while reducing the complications of interventional treatment.In all,PIR,an important part of precision medicine,emphasizing the whole disease management process,including precision diagnosis,comprehensive evaluation,and interventional therapy,maximizes the benefits of patients with limited damage. 展开更多
关键词 precision interventional radiology Anatomical location Comprehensive evaluation Interventional therapy precision diagnosis
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Locating the Small 1999 Frenchman Flat, Nevada Earthquake with InSAR Stacking 被引量:3
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作者 Zhenhong LI 《Journal of Geodesy and Geoinformation Science》 2022年第1期39-49,共11页
Due to high interferometric coherence in the Nevada region,Interferometric Synthetic Aperture Radar(InSAR)phase stacking is capable of mapping coseismic signals from the 27 January 1999,M w 4.8 Frenchman Flat earthqua... Due to high interferometric coherence in the Nevada region,Interferometric Synthetic Aperture Radar(InSAR)phase stacking is capable of mapping coseismic signals from the 27 January 1999,M w 4.8 Frenchman Flat earthquake.This is one of the smallest earthquakes yet studied using InSAR with line-of-sight displacements as small as~1.5 cm.Modelling the event as dislocation in an elastic half space suggests that the fault centroid was located at(115.96°W,36.81°N)with a precision of 0.2~0.3 km(1σ)at a depth of 3.4±0.2 km.Despite the dense local seismic network in southern Nevada,differences as large as 2~5 km were observed between our InSAR earthquake location and those estimated from seismic data.The InSAR-derived magnitude appeared to be greater than that from seismic data,which is consistent with other studies,and believed to be due to the relatively long time interval of InSAR data. 展开更多
关键词 INSAR phase stacking EARTHQUAKE precise location
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A High Precision Forecasting Model and Its Constructing Method for Vein Type Gold Deposits
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作者 Zhang Jun Faculty of Earth Resources, China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2001年第2期100-107,共8页
A high precision forecasting and prospecting model incorporating the “field theory field structure analysis field simulation”, a temporal and spatial structural framework reflecting local extremely fine structure... A high precision forecasting and prospecting model incorporating the “field theory field structure analysis field simulation”, a temporal and spatial structural framework reflecting local extremely fine structures, is established to make an effective extraction and an integrated analysis of multivariate forecasting information. This model can best show not only the coupling between metallogenic anomalous structure, mineralized structure and information structure, but also the extraction, optimization, matching and summarization of key forecasting information. The technological keys to this model are the fine structural analysis of geological and geophysical and geochemical anomalous fields and metallogenic fields, and the establishment of occurrence patterns for the spatial location of orebodies. 展开更多
关键词 high precision forecasting model anomalous structure mineralized structure orebody location.
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精准施肥技术的研究现状及发展趋势 被引量:9
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作者 刘春山 李梦月 +5 位作者 陈思羽 刘洪义 王春光 张艳 陈苏 李志昂 《农机化研究》 北大核心 2025年第7期294-300,共7页
化肥是农作物生长必不可少的营养来源之一,低效施用和未吸收的肥料导致其利用率低下,造成环境污染,影响土地质量,无法保证作物产量。为了形成环境友好型、资源节约型社会,同时增加经济效益,了解精准施肥技术发展现状对我国农业有着重要... 化肥是农作物生长必不可少的营养来源之一,低效施用和未吸收的肥料导致其利用率低下,造成环境污染,影响土地质量,无法保证作物产量。为了形成环境友好型、资源节约型社会,同时增加经济效益,了解精准施肥技术发展现状对我国农业有着重要意义。在国家政策扶持的背景下,阐述了精准施肥国内外发展情况,论述了国内外土壤检测技术,主要从车速监测、施肥量监测、施肥机位置监测、处方图生成方面讲述了我国精准施肥涉及的几大技术,并阐述了优点和局限性,提出了技术研究中的问题并给出发展建议。 展开更多
关键词 精准施肥 土壤检测 车速监测 施肥机位置 处方图生成
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固有频率与电磁时间反演结合的多分支配网故障定位方法 被引量:2
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作者 杨庆 胡逸 +3 位作者 崔浩楠 孙健 王科 徐肖伟 《高电压技术》 北大核心 2025年第3期1103-1113,共11页
针对传统电磁时间反演定位方法在多分支配电线路故障定位中存在定位偏差或失效的问题,提出了一种将固有频率与电磁时间反演结合的多分支配网故障定位方法。首先利用变分模态分解算法与多信号分类算法提取故障信号的固有频率主成分值,然... 针对传统电磁时间反演定位方法在多分支配电线路故障定位中存在定位偏差或失效的问题,提出了一种将固有频率与电磁时间反演结合的多分支配网故障定位方法。首先利用变分模态分解算法与多信号分类算法提取故障信号的固有频率主成分值,然后根据所提出的多分支配网故障区段定位原理确定故障区段位置,最后根据所提出的端口选取策略采用基于单端直接卷积的电磁时间反演方法进行故障精确定位。仿真结果表明,所提方法在不同故障工况下的综合定位误差在41m内,并搭建RG-58同轴电缆试验模型验证了该方法的定位有效性。该研究结果可为现有电磁时间反演方法在多分支配网故障定位中的应用提供新思路。 展开更多
关键词 多分支配电线路 固有频率 故障区段定位 电磁时间反演 故障精确定位
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