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A 15-year-Long catalog of seismicity in the Eastern Tennessee Seismic Zone(ETSZ)using matched filter detection 被引量:1
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作者 Clara Daniels Zhigang Peng 《Earthquake Research Advances》 CSCD 2023年第1期92-105,共14页
We present a detailed catalog of 13671 earthquakes in the Eastern Tennessee Seismic Zone(ETSZ)that spans January 1,2005 to July 31,2020.We apply a matched filter detection technique on over 15 years of continuous data... We present a detailed catalog of 13671 earthquakes in the Eastern Tennessee Seismic Zone(ETSZ)that spans January 1,2005 to July 31,2020.We apply a matched filter detection technique on over 15 years of continuous data,resulting in arguably the most complete catalog of seismicity in the ETSZ yet.The magnitudes of newly detected events are determined by computing the amplitude ratio between the detections and templates using a principal component fit.We also compute the b-value for the new catalog and comparatively relocate a subset of newly detected events using XCORLOC and hypoDD,which shows a more defined structure at depth.We find the greatest concentration along and to the east of the New York-Alabama Lineament,as defined by the magnetic anomaly,supporting the argument that this feature likely is related to the generation of seismicity in the ETSZ.We examine seismicity in the vicinity of the Watts Bar Reservoir,which is located about 5 km from the epicenter of the M_(W) 4.4 December 12,2018 Decatur,Tennessee earthquake,and find possible evidence for reservoir modulated seismicity in this region.We also examine seismicity in the entire ETSZ to search for a correlation between shallow earthquakes and seasonal hydrologic changes.Our results show limited evidence for hydrologicallydriven shallow seismicity due to seasonal groundwater levels in the ETSZ,which contradicts previous studies hypothesizing that most intraplate earthquakes are associated with the dynamics of hydrologic cycles. 展开更多
关键词 Eastern Tennessee Seismic zone Matched filter detection Intraplate earthquakes Reservoir modulated seismicity
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Sensor scheduling for ground maneuvering target tracking in presence of detection blind zone 被引量:10
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作者 XU Gongguo SHAN Ganlin DUAN Xiusheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期692-702,共11页
Continuous and stable tracking of the ground maneuvering target is a challenging problem due to the complex terrain and high clutter. A collaborative tracking method of the multisensor network is presented for the gro... Continuous and stable tracking of the ground maneuvering target is a challenging problem due to the complex terrain and high clutter. A collaborative tracking method of the multisensor network is presented for the ground maneuvering target in the presence of the detection blind zone(DBZ). First, the sensor scheduling process is modeled within the partially observable Markov decision process(POMDP) framework. To evaluate the target tracking accuracy of the sensor, the Fisher information is applied to constructing the reward function. The key of the proposed scheduling method is forecasting and early decisionmaking. Thus, an approximate method based on unscented sampling is presented to estimate the target state and the multi-step scheduling reward over the prediction time horizon. Moreover, the problem is converted into a nonlinear optimization problem, and a fast search algorithm is given to solve the sensor scheduling scheme quickly. Simulation results demonstrate the proposed nonmyopic scheduling method(Non-MSM) has a better target tracking accuracy compared with traditional methods. 展开更多
关键词 sensor scheduling ground maneuvering target detection blind zone(DBZ) decision tree optimization
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Studies of Active Ingredients in Cough Syrup by Capillary Zone Electrophoresis with Amperometric Detection 被引量:1
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作者 ZHOUTian-shu WANGAi-fang +2 位作者 WUFang SHIGuo-yue FANGYu-zhi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第4期386-389,共4页
The present paper covers a simple, reliable and reproducible method, based on capillary zone electrophoresis(CZE) with amperometric detection(AD), for the separation and the determination of ephedrine hydrochloride, p... The present paper covers a simple, reliable and reproducible method, based on capillary zone electrophoresis(CZE) with amperometric detection(AD), for the separation and the determination of ephedrine hydrochloride, promethazine hydrochloride and codeine phosphate. Under the optimal conditions, the three analytes were base-line separated completely within 16 min. Good linear relationships between the peak heights and the concentrations of the three analytes were obtained with the correlation coefficients better than 0 9993. The method was directly applied to the determination of the active ingredients in pharmaceutical preparations and the assay results were satisfactory. 展开更多
关键词 Capillary zone electrophoresis Amperometric detection Ephedrine hydrochloride Promethazine hydrochloride Codeine phosphate
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Detection and Separation of Inorganic Cations in Natural, Potable, and Wastewater Samples Using Capillary Zone Electrophoresis with Indirect UV Detection 被引量:1
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作者 Lara Varden Fadi Bou-Abdallah 《American Journal of Analytical Chemistry》 2017年第1期81-94,共14页
Capillary zone electrophoresis (CZE) is a sensitive and rapid technique for determining traces of inorganic cations in water samples. CZE with indirect UV-diode array detection (CZE-DAD) was utilized to identify sever... Capillary zone electrophoresis (CZE) is a sensitive and rapid technique for determining traces of inorganic cations in water samples. CZE with indirect UV-diode array detection (CZE-DAD) was utilized to identify several inorganic cations in natural, potable, and wastewater samples. A pH 4.35 background electrolyte system was employed and consisted of 15 mM imidazole, 8 mM malonic acid, 2 mM 18-crown-6 ether as complexing agents, 10% v/v methanol as an organic modifier with indirect absorbance reference at 214 nm. The CZE method involved electromigration injection at 5 kV for 5 s, a separation voltage of 20 kV at 25℃, and a detection wavelength of 280 nm. Six main cations (ammonium , potassium K+, calcium Ca2+, sodium Na+, magnesium Mg2+, and lead Pb2+) were tested, and all but lead, were detected in the water samples at concentrations between 0.03 and 755 ppm with a detection limit ranging between 0.023 and 0.084 ppm. The successful evaluation of the proposed methodology allowed us to reliably detect and separate six metal ions in different water samples without any pretreatment. All water samples were collected from Northern New York towns and the Raquette River water system, the third longest river in New York State and the largest watershed of the central and western Adirondacks. 展开更多
关键词 Capillary zone ELECTROPHORESIS Indirect UV detection INORGANIC CATIONS Northern New YORK Raquette River Adirondack Watershed
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Height Detection and Analysis of Water Flowing Fractured Zone of Coal Face
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作者 Ziyang Feng 《Computational Water, Energy, and Environmental Engineering》 2021年第4期131-139,共9页
Taking 91105 working face as the research object, the observation method of water flowing fracture<span style="font-family:Verdana;">d</span><span style="font-family:Verdana;"> zo... Taking 91105 working face as the research object, the observation method of water flowing fracture<span style="font-family:Verdana;">d</span><span style="font-family:Verdana;"> zone and the layout of mining holes were determined by analyzing the field geological structure</span><span style="font-family:Verdana;">. </span><span style="font-family:Verdana;">It was shown that the fractured zone height and the ratio given by the measured method were 52.33 and 12.46, respectively. By the numerical simulation method with the software of UDEC, the fractured zone height and the ratio were 42.5 and 10.12. By comparison of measured height data and UDEC numerical simulation, there were some differences between the measured height and the calculated results of UDEC numerical simulation method. The method of simulation can be used as the technical basis for the design of waterproof coal pillar in the future.</span> 展开更多
关键词 Water Flowing Fractured zone Height detection Fracture Mining Ratio Numerical Simulation
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Capillary Electrophoretic Determination of Jinggangmycin A in Formulations Using Direct UV Detection 被引量:1
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作者 Jin HE Xin LIU Yi Shi LIU Zi Niu YU 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第11期1511-1514,共4页
A simple, fast and reliable method was developed for the analysis of jinggangmycin A (validamycin A) in commercial formulations. The running buffer used was acetate buffer (100 mmol/L, pH 4.7) with 15 kV as the ap... A simple, fast and reliable method was developed for the analysis of jinggangmycin A (validamycin A) in commercial formulations. The running buffer used was acetate buffer (100 mmol/L, pH 4.7) with 15 kV as the applied voltage. The detection was achieved by using direct UV mode at 200 nm and the detection limit was 0.2 μg/mL. Linearity in the concentration range of 5-500 μg/mL was excellent (RE 〉 0.999). The run-to-run repeatability (n = 3), as expressed by the relative standard deviation (RSD) for migration times and peak areas were less than 0.5% and 3.0% respectively. The mean recovery ranged from 97.2% to 101.4%. 展开更多
关键词 Jinggangmycin A validamycin A capillary zone electrophoresis direct UV detection.
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A New Method of Early Short Circuit Detection 被引量:1
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作者 Feng Du Weigang Chen +1 位作者 Yue Zhuo Michael Anheuser 《Journal of Power and Energy Engineering》 2014年第4期432-427,共6页
To reduce the pressure on contacts and circuit breaker and realize the zone selective interlocking (ZSI) function above the instantaneous protection threshold (e.g., >10In), the short circuit current needs to be ea... To reduce the pressure on contacts and circuit breaker and realize the zone selective interlocking (ZSI) function above the instantaneous protection threshold (e.g., >10In), the short circuit current needs to be early detected. The state-of–art of early short circuit detection (ESCD) method is reviewed. Based on the equivalent model of the short circuit, a new method based on the current and its integration is proposed. The prospective current value can be detected in the early stage of the short circuit. According to the evaluation result, the short circuit current can be early forecasted with the proposed method. 展开更多
关键词 EARLY SHORT Circuit detection zone Selective INTERLOCKING Instantaneous Protection
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Detection of Catecholic Compounds with Field-ampilfied CZE-Amperometry
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作者 HU Shen, PANG Dai-wen , HU Yong-gang , CHENG Jie-ke (Department of Chemistry, Wuhan University, Wuhan, 430072 ) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1997年第3期221-228,共8页
On-column sample stacking technique has been used extensively in capillary zone electrophoresis (CZE) to enhance the sensitivity of the measurements with UV-Vis detection. However, the detection limits for CZE-separat... On-column sample stacking technique has been used extensively in capillary zone electrophoresis (CZE) to enhance the sensitivity of the measurements with UV-Vis detection. However, the detection limits for CZE-separation are still limit- ed due to the poor sensitivity of a UV-Vis detector. We incorporated field-amplified sample stacking technique into CZE with amperometric detection. Compared with the conventional electromigration injection , a negative peak of water was observed and a great enhancement of signals was obtained. The results in phosphate buffer with sodium dodecyl sulfate (SDS ) and 2-N-(morpholino) ethane sulphonic acid ( MES ) buffer were compared. Subnanomolar concentration limits for cate- cholamine neurotransmitters (dopamine, norepinephrine , epinephriine) and isopro- terenol were achieved in the 25 um capillary with two or three orders of magnitude lower than those with amperometric detection reported previously. 展开更多
关键词 Capillary zone electrophoresis Amperometric detection STACKING
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Performance Assessment of Islanding Detection for Mul-ti-inverter Grid-connected Photovoltaic Systems
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作者 Xing Zhang Dong Xie 《Energy and Power Engineering》 2013年第4期1517-1520,共4页
Islanding detection is an essential function for safety and reliability in grid-connected Distributed Generation Systems (DGS). Passive and active islanding detection methods have been analyzed in literature consideri... Islanding detection is an essential function for safety and reliability in grid-connected Distributed Generation Systems (DGS). Passive and active islanding detection methods have been analyzed in literature considering DGS with only one inverter connected to the utility. With the big scale application of photovoltaic (PV) power systems, islanding detection technology of multi-inverter DGS has been paid more attention. This paper analyzes the performance of diverse islanding detection methods in multiple inverters grid-connected PV systems. Non-Detection Zones (NDZ) of multi-inverter systems in a load parameter space are used as analytical tool. The paper provides guidance for the islanding detection design in multiple grid-connected inverters. 展开更多
关键词 PHOTOVOLTAIC Power Systems ISLANDING detection Multi-inverter Non-detection zoneS
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Improved Active Islanding Detection Technique for Multi-Inverter Power System
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作者 Jie Zhang Yu-Hua Cheng +1 位作者 Kai Chen Gen Qiu 《Journal of Electronic Science and Technology》 CAS CSCD 2021年第2期186-195,共10页
Due to the increased penetration of multi-inverter distributed generation(DG)systems,different DG technologies,inverter control methods,and other inverter functions are challenging the capabilities of islanding detect... Due to the increased penetration of multi-inverter distributed generation(DG)systems,different DG technologies,inverter control methods,and other inverter functions are challenging the capabilities of islanding detection.In addition,multi-inverter networks connecting the distribution system point of common coupling(PCC)create islanding at paralleling inverters,which adds the vulnerability of islanding detection.Furthermore,available islanding detection must overcome more challenges from non-detection zones(NDZs)under reduced power mismatches.Therefore,in this study,a new method called parameter self-adapting active islanding detection was utilized to minimize the dilution effect and reduce NDZs in multi-inverter power systems.The method utilizes an active frequency drift(AFD)method and applies a positive feedback gain of adoption parameters,which significantly minimizes NDZs at parallel inverters.The simulation and experimental outcomes indicate that the proposed method can effectively weaken the dilution effect in multi-inverter networks connecting the distribution system PCC. 展开更多
关键词 Active frequency drift(AFD) active islanding detection method multi-inverter power system non-detection zones(NDZs)
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Fault detection by reflected surface waves based on ambient noise interferometry
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作者 Ning Gu Haijiang Zhang +1 位作者 Nori Nakata Ji Gao 《Earthquake Research Advances》 CSCD 2021年第4期22-27,共6页
Detecting subsurface fault structure is important for evaluating potential earthquake risks associated with active faults.In this study,we propose a new method to detect faults using reflected surface waves observed i... Detecting subsurface fault structure is important for evaluating potential earthquake risks associated with active faults.In this study,we propose a new method to detect faults using reflected surface waves observed in ambient noise cross correlation functions.Ambient noise tomography using direct surface waves obtained from ambient noise interferometry has been widely used to characterize active fault zones.In cases where a strong velocity contrast exists across the fault interface,fault-reflected surface waves are expected.We test this idea using a linear array deployed in the Suqian segment of Tanlu fault zone in Eastern China.The fault-reflected surface waves can be clearly seen in the cross-correlation functions of the ambient noise data,and the spatial position of the fault on the surface is close to the stations where the reflected signals first appear.Potentially reflected surface waves could also be used to infer the dip angle,fault zone thickness and the degree of velocity contrast across the fault by comparing synthetic and observed waveforms. 展开更多
关键词 Fault detection Ambient noise Cross-correlation functions Reflected surface wave Tanlu fault zone
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A Novel Island Detection Methodology for the Realization of Smart Grid 被引量:1
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作者 Hammad Khan Anastasia Tjandra +1 位作者 Herbert Iu Victor Sreeram 《Smart Grid and Renewable Energy》 2011年第4期330-337,共8页
Responding to the problem of increased load demand, progress has been made to develop a new smarter infrastructure, which employs a decentralised approach. This smart decentralised system, termed smart grid, is compos... Responding to the problem of increased load demand, progress has been made to develop a new smarter infrastructure, which employs a decentralised approach. This smart decentralised system, termed smart grid, is composed of micro grids which utilise a combination of distributed energy resources (DER). The DERs can either be operated in parallel with the grid or in autonomous condition (intentional-islanding). Operating the DER under intentional islanding condition is seen as the next stage in smart grid’s future development which requires intelligent control implementation. In order to utilise this intelligent control, immediate detection of islanding is essential. This paper proposes a new smarter islanding detection method, which implements the forecast capability of smart grid by detecting the fluctuations before islanding occurs. The proposed method has been tested in simulation and compared against the current islanding detection methods. The simulation results have successfully proven the benefits of the new proposed method over the current methodologies in island detection. 展开更多
关键词 Distributed Generation (DG) ISLANDING Non-detection zone (NDZ) Circuit BREAKER Contact PARTING Time
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一种混合低谐无盲区的孤岛检测方法
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作者 宋绍楼 马超 +1 位作者 刘昕明 李旸 《电源学报》 CSCD 北大核心 2024年第2期328-335,共8页
主动式检测方法作为一种常用的孤岛检测方法,虽然可以通过增加扰动强度使孤岛检测盲区得以减小,但同时会增大对电网的谐波污染程度。针对此问题,提出了一种混合模糊低谐无盲区的孤岛检测方法,即首先对盲区进行判断,优先使用对电网无谐... 主动式检测方法作为一种常用的孤岛检测方法,虽然可以通过增加扰动强度使孤岛检测盲区得以减小,但同时会增大对电网的谐波污染程度。针对此问题,提出了一种混合模糊低谐无盲区的孤岛检测方法,即首先对盲区进行判断,优先使用对电网无谐波污染的被动式孤岛检测方法,若此时处于被动式检测方法盲区之内,则使用一种具有模糊扰动控制的对输出电流第二、四个1/4周期进行扰动的模糊低谐孤岛检测方法。最后搭建相应的仿真模型对所提方法的有效性进行验证。 展开更多
关键词 孤岛检测 谐波 检测盲区 模糊控制
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走滑断裂带三维地震特征增强处理与描述研究
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作者 龚伟 吕海涛 +2 位作者 林新 李弘艳 张荣 《西北地质》 CAS CSCD 北大核心 2024年第2期59-66,共8页
走滑断裂带由于纵向断距小,超深层地震信号弱,常规叠前深度偏移地震资料难以满足超深层断裂带精细描述需求。为提高断裂带成像精度,指导走滑断裂带解释描述和评价部署,以顺北地区走滑断裂带发育区三维地震资料为例,建立了一套以提高地... 走滑断裂带由于纵向断距小,超深层地震信号弱,常规叠前深度偏移地震资料难以满足超深层断裂带精细描述需求。为提高断裂带成像精度,指导走滑断裂带解释描述和评价部署,以顺北地区走滑断裂带发育区三维地震资料为例,建立了一套以提高地震资料品质的保真保幅优化处理、频谱恢复提高分辨率处理、频谱分解处理、频率域多尺度断裂检测等技术为主的走滑断裂带地震特征增强处理与描述技术,该技术组合有效拓宽了地震数据频带,提高了地震数据分辨率,使超深走滑断裂带成像精度更高,为超深走滑断裂带的精细解释、描述评价、三维雕刻提供了高品质资料基础。结合顺北地区前人研究成果,综合利用频谱恢复提高分辨率处理、频谱分解处理、频率域断裂检测数据,不同尺度断裂带特征及断储关系预测效果更好,为进一步评价断裂带和部署井位提供了技术支撑。 展开更多
关键词 超深走滑断裂带 保真保幅优化处理 频谱恢复提高分辨率处理 频谱分解处理 断裂带检测
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基于充电导体模型的水力压裂电磁响应特征分析
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作者 李帝铨 李富 +3 位作者 张乔勋 黄亚 别勇杰 胡艳芳 《石油地球物理勘探》 EI CSCD 北大核心 2024年第1期151-159,共9页
随着中国非常规、超低渗油气资源的大力开发,压裂监测技术迎来重大发展机遇。电磁法在地球物理探测方面具有成本低、时效性强、探测深度大等优点,但面对大深度压裂环境,电磁压裂监测技术的可行性亟须论证。基于充电导体和电偶极源扩散... 随着中国非常规、超低渗油气资源的大力开发,压裂监测技术迎来重大发展机遇。电磁法在地球物理探测方面具有成本低、时效性强、探测深度大等优点,但面对大深度压裂环境,电磁压裂监测技术的可行性亟须论证。基于充电导体和电偶极源扩散电磁场理论,首先构建了不同深度和不同长度下的裂缝压裂模型,分析了各模型的地面总场及异常场的电磁响应特征。分析结果表明:利用井地电磁法进行压裂监测时,观测总场对裂缝长度增加引起的电磁响应不敏感,异常场存在低值带;深度为4000 m时,电磁异常小于1%,深度越大异常场衰减越严重,且相邻测点间异常场的绝对值与深度呈负相关,电磁法压裂监测技术难以兼顾探测精度与探测深度。然后,通过建立压裂监测物理模型,分析实测数据电磁异常曲线特征,验证了理论计算的正确性。最后,结合前人理论成果和实践经验,提出了一种井中激发—地面接收的测网式电磁法压裂监测观测系统,对测区范围与测点间距进行合理约束,系统具有野外施工简捷、监测深度大等优势,为电磁法压裂监测提供了新的发展方向。 展开更多
关键词 充电导体 电磁监测 探测深度 低值带 水力压裂
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东昆仑断裂带东段微震检测与构造分析 被引量:1
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作者 马胜男 李红谊 +2 位作者 黄雅芬 马玉虎 马建新 《震灾防御技术》 CSCD 北大核心 2024年第2期276-287,共12页
本文整理了一套包括微震检测、地震去噪、震相拾取和地震定位的构建高精度地震目录数据的处理流程。收集了青海省内东昆仑断裂带东段20个数字地震台站记录的2009−2018年的连续地震数据,并应用该流程进行微震检测、去噪和定位。首先,从... 本文整理了一套包括微震检测、地震去噪、震相拾取和地震定位的构建高精度地震目录数据的处理流程。收集了青海省内东昆仑断裂带东段20个数字地震台站记录的2009−2018年的连续地震数据,并应用该流程进行微震检测、去噪和定位。首先,从台网中心提供的3198个地震事件目录中筛选出1200个信噪比高且震相较为明显的地震事件作为模板事件,利用基于图像处理器加速的模板匹配定位方法(GPU-M&L)进行遗漏地震的检测与识别,然后利用基于神经网络的地震波形去噪方法进行去噪处理,再结合基于深度学习的震相拾取技术和双差定位方法对去噪后的地震事件进行震相拾取和定位。使用GPU-M&L共检测出13318个地震事件,约为台网地震目录事件数量的4.2倍;去噪后得到7514个地震事件,约为台网地震目录事件数量的2.3倍,完备震级从台网目录的ML 1.5降低至ML 0.9。定位后共获得7247个地震事件,精定位结果显示,东昆仑断裂带东段的地震以中小震为主,在空间上呈窄条带状或簇状分布,震源深度的优势分布深度为0~15 km;在101°E附近地震的空间展布发生变化,主要沿阿万仓断裂带向东南展布;在玛沁-玛曲段可能存在地震空区。本研究的微震结果为研究东昆仑断裂带东段地震活动性、发震断层的深部构造等提供了重要的数据基础。 展开更多
关键词 东昆仑断裂 微震检测 匹配定位技术 地震去噪 双差定位
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基于机器视觉的小型零件圆度测量
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作者 丁哲文 张瑞 +2 位作者 朱振伟 赵华东 刘丙康 《组合机床与自动化加工技术》 北大核心 2024年第4期171-174,180,共5页
针对小型零件圆度误差测量效率低、精度不稳定等问题,提出了一种基于机器视觉的小型零件圆度测量方法。通过建立机器视觉检测平台,获得零件图像。经过预处理后,通过Canny算子结合8领域扩张算法划定感兴趣区域,采用多项式插值亚像素边缘... 针对小型零件圆度误差测量效率低、精度不稳定等问题,提出了一种基于机器视觉的小型零件圆度测量方法。通过建立机器视觉检测平台,获得零件图像。经过预处理后,通过Canny算子结合8领域扩张算法划定感兴趣区域,采用多项式插值亚像素边缘检测算法获得边缘坐标;然后,利用改进区域搜索算法确定准圆心,并通过最小区域法的几何结构找出最小区域圆心,从而计算圆度误差。实验结果表明,圆度误差的测量重复精度为8.1μm,能够实现小型零件的非接触测量。 展开更多
关键词 机器视觉 圆度误差 边缘检测 最小区域法 小型零件
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癫痫高频振荡节律检测与发作始发区定位系统软件设计
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作者 覃宏振 万雄波 +1 位作者 杜玉晓 吴敏 《北京生物医学工程》 2024年第3期267-273,279,共8页
目的癫痫脑电信号中的高频振荡节律是发作始发区的显著生物标记物,其精确检测对术前发作始发区定位至关重要。而复杂的检测和定位方法需要专门的软件将其封装处理,并提供直观的数据分析界面,以供研究者和临床医生使用,为此本文设计一种... 目的癫痫脑电信号中的高频振荡节律是发作始发区的显著生物标记物,其精确检测对术前发作始发区定位至关重要。而复杂的检测和定位方法需要专门的软件将其封装处理,并提供直观的数据分析界面,以供研究者和临床医生使用,为此本文设计一种直观的高频振荡节律检测与发作始发区定位系统软件HFOLab。方法采用模块化的设计方法,将高频振荡节律检测方法和发作始发区定位方法设计为两个子模块,将检测结果可视化并输入定位子模块。考虑检测方法误报问题和人工检测需求,分别设计高频振荡节律辅助校验和辅助检测子模块,为专家校验和标记高频振荡节律提供直观依据。结果采用20名癫痫患者的脑电数据,对HFOLab进行初步试验。试验结果表明,HFOLab具有直观的数据分析界面,可对检测结果可视化,并为专家校验和标记高频振荡节律提供直观的依据。20名患者的高频振荡节律平均检测灵敏度(Ripples:92.4%;Fast ripples:90.3%)和平均误报率(Ripples:9.2%;Fast ripples:10.7%)良好,整体发作始发区定位灵敏度和特异性分别为78.9%和77.4%。结论HFOLab可有效检测高频振荡节律并定位发作始发区,可辅助专家校验和标记高频振荡节律,为应用高频振荡节律定位发作始发区的临床试验提供新的工具。 展开更多
关键词 癫痫 高频振荡节律 发作始发区 检测 定位
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双反射与透射结合的激光引信扫描系统
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作者 丁星 侯望高 +2 位作者 牛兰杰 张向荣 梁超 《探测与控制学报》 CSCD 北大核心 2024年第4期46-52,共7页
针对激光引信周向扫描系统光束发散角大且存在扫描盲区的问题,设计了一种基于双反射与透射结合的激光引信扫描系统。阐述了系统结构尺寸的约束并通过光线追踪分别对系统扫描过程中光束发散角和扫描角度进行了仿真,并研究了超环面和六棱... 针对激光引信周向扫描系统光束发散角大且存在扫描盲区的问题,设计了一种基于双反射与透射结合的激光引信扫描系统。阐述了系统结构尺寸的约束并通过光线追踪分别对系统扫描过程中光束发散角和扫描角度进行了仿真,并研究了超环面和六棱台镜面的面型参数调整与光束发散角、扫描角度之间的影响。仿真结果表明:通过控制光阑位置可以实现单窗口的扫描角度达61°,六窗口组合可实现无盲区扫描;通过调整反射面参数来矫正透射场曲可实现全扫描角度光束最大发散角为0.034°;扫描路线会出现波浪式起伏,需要进一步匹配收发视场实现远距离无盲区扫描。该系统为激光引信远距离周向探测提供了技术支撑。 展开更多
关键词 激光引信 周向扫描系统 探测距离 视角盲区 离轴双反射
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强富水区山岭隧道穿越断层破碎带施工技术研究
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作者 谭艳臣 李德 +5 位作者 唐亮 常泽洲 王富春 宋健 王志浩 金熙宾 《科技创新与应用》 2024年第12期173-176,共4页
为降低隧道穿越断层破碎带施工中的涌水突泥风险,该文依托古兜山隧道实体工程,采用“TSP+地质雷达+超前地质钻孔”的地质超前预报技术,探明隧道掌子面前方的地层状况和富水程度,提出富水区隧道穿越断层破碎带施工关键技术。提出隧道洞... 为降低隧道穿越断层破碎带施工中的涌水突泥风险,该文依托古兜山隧道实体工程,采用“TSP+地质雷达+超前地质钻孔”的地质超前预报技术,探明隧道掌子面前方的地层状况和富水程度,提出富水区隧道穿越断层破碎带施工关键技术。提出隧道洞口明挖法与隧道洞内光面爆破技术及洞内围岩段的双侧壁导坑法、单侧壁导坑法、三台阶七部法的开挖方式;采用S-Ⅴb型隧道衬砌结构型式与全断面帷幕注浆、加强泄水等技术相结合的支护方式,其中的整体承载结构为初期支撑系统和二次模筑衬砌的组合结构。该施工关键技术可有效避免古兜山隧道施工的突水涌泥现象,可指导类似工程的施工。 展开更多
关键词 强富水区 断层破碎带 隧道 施工技术 超前探测
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