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Effect of Specific Verbal Instructions on the Identification of Pain Location during a Passive Straight Leg Raise Test
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作者 Masae Ikeya Takumi Jiroumaru +2 位作者 Hitomi Bunki Noriyuki Kida Teruo Nomura 《Open Journal of Therapy and Rehabilitation》 2023年第2期45-53,共9页
Musculoskeletal pain is common. Because pain is subjective, objectively describing it is crucial. However, pain assessment may cause distress in patients;therefore, physical therapists (PTs) should conduct these tests... Musculoskeletal pain is common. Because pain is subjective, objectively describing it is crucial. However, pain assessment may cause distress in patients;therefore, physical therapists (PTs) should conduct these tests quickly and accurately. Simple and clear instructions are recommended for pain assessment. However, few studies have provided evidence to support this hypothesis. Correspondingly, this study aimed to confirm the effectiveness of specific verbal instructions for pain location during five consecutive Passive Straight Leg Raise (PSLR) tests. The 28 asymptomatic participants (age 27.4 ± 9.6 years) who provided informed consent received five consecutive PSLR tests: three without and two with specific verbal instructions to ascertain pain intensity, quality, and location. The participants drew pain locations on a body chart and described the pain intensity and quality after each test. All participants were interviewed regarding the differences they noted in the presence and absence of specific verbal instructions. Each pain location was classified into one of ten areas for statistical analysis. The proportion of participants who changed the pain location was compared between the tests using McNemar’s test, and the kappa coefficient was confirmed for consistency of pain location. There was a significant difference in the proportion of participants who changed their pain location between the second and third tests and from the third to the fourth test (McNemar’s test: p = 0.003). Kappa coefficients had low consistency (κ = 0.28) just after receiving the specific verbal instructions in the fourth test compared to the third test. Consistency improved in the fifth test (κ = 0.57);93% of the participants answered that the pain location had become clearer. This study revealed the effects of specific verbal instructions in identifying pain locations. This detailed information may help PTs provide appropriate treatment and contribute to reducing pain in clinical settings. 展开更多
关键词 Specific Verbal Instructions Pain location Pain Assessment passive Straight Leg Raise Test
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PASSIVE LOCATION AND ACCURACY ANALYSIS USING TDOA INFORMATION OF MULTI-STATIONS 被引量:3
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作者 杨林 周一宇 孙仲康 《Chinese Journal of Aeronautics》 SCIE EI CSCD 1998年第1期38-44,共7页
A new exact, explicit, uniterative, and computationally efficient solution of nonlinear equation set for estimation of emitter position based on the time differences of arrival (TDOA) measured by multi stations is pr... A new exact, explicit, uniterative, and computationally efficient solution of nonlinear equation set for estimation of emitter position based on the time differences of arrival (TDOA) measured by multi stations is proposed. The accuracy analysis of the l 展开更多
关键词 positioning devices locates system passive location TDOA ACCURACY ANALYSIS GDOP
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ACCURACY ANALYSIS OF PASSIVE LOCATION SYSTEM WITH PHASE DIFFERENCE RATE MEASUREMENT 被引量:1
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作者 邓新蒲 姜文利 周一宇 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2000年第4期222-227,共6页
The conventional mono station passive location techniques of direction finding are low in speed and accuracy, due to the little information available. In this paper, a novel measurement rate (derivative) of phase diff... The conventional mono station passive location techniques of direction finding are low in speed and accuracy, due to the little information available. In this paper, a novel measurement rate (derivative) of phase difference from a two element antenna array (interferometer) is introduced, accuracy of a passive location system with this measurement and directions of arrival (DOA) is analyzed, and the Cramer Rao bound of location error of this system for 3D location is examined by simulations. 展开更多
关键词 passive location phase DIFFERENCE RATE location ACCURACY analysis INTERFEROMETER
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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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Multiple moving sources passive location based on multiset canonical correlation analysis
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作者 禹华钢 Huang Gaoming Gao Jun 《High Technology Letters》 EI CAS 2013年第2期197-202,共6页
To solve the problem of multiple moving sources passive location,a novel blind source separation(BSS) algorithm based on the multiset canonical correlation analysis(MCCA) is presented by exploiting the different tempo... To solve the problem of multiple moving sources passive location,a novel blind source separation(BSS) algorithm based on the multiset canonical correlation analysis(MCCA) is presented by exploiting the different temporal structure of uncorrelated source signals first,and then on the basis of this algorithm,a novel multiple moving sources passive location method is proposed using time difference of arrival(TDOA) and frequency difference of arrival(FDOA) measurements.The key technique of this location method is TDOA and FDOA joint estimation,which is based on BSS.By blindly separating mixed signals from multiple moving sources,the multiple sources location problem can be translated to each source location in turn,and the effect of interference and noise can also be removed.The simulation results illustrate that the performance of the MCCA algorithm is very good with relatively light computation burden,and the location algorithm is relatively simple and effective. 展开更多
关键词 典型相关分析 无源定位 基础 移动 盲源分离 到达频差 TDOA 定位方法
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A Two-Station Passive Locating Solution Independent of the Baseline Length 被引量:1
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作者 Tao Yu 《Open Journal of Applied Sciences》 2020年第7期476-485,共10页
The two-station positioning system based on time difference and azimuth measurement has measurement redundancy. Therefore, not only can a positioning solution which is completely independent of the baseline length bet... The two-station positioning system based on time difference and azimuth measurement has measurement redundancy. Therefore, not only can a positioning solution which is completely independent of the baseline length between two stations be derived, but also the baseline length can be solved as an unknown quantity. These findings not only enhance the performance of the two-station positioning system, but also provide a design basis for the construction of a self-organizing dynamic intelligent positioning system. 展开更多
关键词 Positioning without Baseline Two-Station locating Time Difference Direction Finding Path Difference passive location Self-Organizing System
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A Doppler Location Method Based on Virtual Path Difference
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作者 Yu Tao 《Journal of Electronic & Information Systems》 2023年第1期20-25,共6页
This paper presents a Doppler passive location method for moving targets with fixed single station using the Doppler frequency shift and time difference information.First,based on the relationship between frequency sh... This paper presents a Doppler passive location method for moving targets with fixed single station using the Doppler frequency shift and time difference information.First,based on the relationship between frequency shift and path difference,the virtual path difference is calculated from the measured value of Doppler frequency shift by means of mean value correction.Then,under the assumption that the target is moving at a constant speed along a straight line,two coaxial virtual double base arrays are constructed by using the moving track of the moving target based on the method of fixed period time difference.On this basis,the moving distance of the moving target can be calculated by using the ratio relationship between the frequency difference and the radial distance between the two adjacent detection points in the middle of the array,and the linear solution of the two double base path difference positioning equations.At this point,the relative coordinate position of the moving target can be obtained by directly using the linear solution of the double base path difference positioning equation again. 展开更多
关键词 Fixed single station passive location Doppler frequency Doppler frequency change rate Frequency shift-path difference equation Virtual path difference
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Research on Estimation of Time Delay Difference in Passive Locating for Impulse Signal
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作者 徐复 何文翔 +1 位作者 惠俊英 余赟 《Defence Technology(防务技术)》 SCIE EI CAS 2011年第3期167-175,共9页
Analyzed the relation between time delay difference and time delay estimation errors, based on the principles of three-point locating, a reformed threshold method for time delay difference estimation of impulse signal... Analyzed the relation between time delay difference and time delay estimation errors, based on the principles of three-point locating, a reformed threshold method for time delay difference estimation of impulse signals, called as amendment estimation for short, is developed by introducing channel equalization technique to its conventional version, named as direct estimation in this paper, to improve the estimation stability. After inherent relationship between time delay and phase shift of signals is analyzed, an integer period error compensation method utilized the diversities of both contribution share and contribution mode of concerned estimates is proposed under the condition of high precision phase lag estimation. Finally, a cooperative multi-threshold estimation method composed of amendment and direct estimations to process impulse signals with three thresholds is established. In sea trials data tests of passive locating, this method improves the estimation precision of time delay difference efficiently. The experiments verify the theoretical predictions. 展开更多
关键词 information processing technique passive locating for IMPULSE signal three point positioning time delay DIFFERENCE ESTIMATION amendment ESTIMATION INTEGER period error compensation cooperative MULTI-THRESHOLD ESTIMATION
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N受事+V+Location类结构的题元分析
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作者 汪祎 《新余学院学报》 2013年第6期68-70,共3页
运用题元理论探讨隐形被动句中N受事+V+Location一类句式的动词特征及该类句式与其深层结构、存现句之间的关系,研究发现:(1)动词语义上的准入条件为:[+致使义]、[+生命体参与]、[+主体控制]、[+位移义]。(2)功能上N受事+V+Location结... 运用题元理论探讨隐形被动句中N受事+V+Location一类句式的动词特征及该类句式与其深层结构、存现句之间的关系,研究发现:(1)动词语义上的准入条件为:[+致使义]、[+生命体参与]、[+主体控制]、[+位移义]。(2)功能上N受事+V+Location结构中的动词吸收深层结构中的施事题元与标志词"把",指派能力不变。(3)N受事+V+Location类句式只能与N受事+Location+V着结构进行转换。 展开更多
关键词 隐形被动 题元理论 N受事+V+location类结构
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Joint TDOA and AOA location algorithm 被引量:31
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作者 Congfeng Liu Jie Yang Fengshuai Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第2期183-188,共6页
For the joint time difference of arrival(TDOA) and angle of arrival(AOA) location scene,two methods are proposed based on the rectangular coordinates and the polar coordinates,respectively.The problem is solved pe... For the joint time difference of arrival(TDOA) and angle of arrival(AOA) location scene,two methods are proposed based on the rectangular coordinates and the polar coordinates,respectively.The problem is solved perfectly by calculating the target position with the joint TDOA and AOA location.On the condition of rectangular coordinates,first of all,it figures out the radial range between target and reference stations,then calculates the location of the target.In the case of polar coordinates,first of all,it figures out the azimuth between target and reference stations,then figures out the radial range between target and reference stations,finally obtains the location of the target.Simultaneously,simulation analyses show that the theoretical analysis is correct,and the proposed methods also provide the application of the joint TDOA and AOA location algorithm with the theoretical basis. 展开更多
关键词 passive location joint time difference of arrival (TDOA)and angle of arrival (AOA) location direct solution method perfor-mance analysis.
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ANALYSIS OF LOCATION ACCURACY FOR AN EMITTER USING SATELLITE-MOUNTED INTERFEROMETER 被引量:3
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作者 周一宇 郭志刚 +1 位作者 陆伟宁 朱伟强 《Chinese Journal of Aeronautics》 SCIE EI CSCD 1998年第1期30-37,共8页
Location for a ground emitter using a satellite mounted two dimensional interferometer is modeled and an analysis method is proposed, then the influences on the location caused by a random measurement error and syste... Location for a ground emitter using a satellite mounted two dimensional interferometer is modeled and an analysis method is proposed, then the influences on the location caused by a random measurement error and system parameter errors, such as satellite 展开更多
关键词 SATELLITE ATTITUDE control positioning devices phase switching INTERFEROMETERS error ananlysis passive location
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Direct solution for fixed source location using well-posed TDOA and FDOA measurements 被引量:6
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作者 LIU Congfeng YUN Jinwei SU Juan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期666-673,共8页
Based on the time differences of arrival(TDOA) and frequency differences of arrival(FDOA) measurements of the given planar stationary radiation source, the joint TDOA/FDOA location algorithm which solves the location ... Based on the time differences of arrival(TDOA) and frequency differences of arrival(FDOA) measurements of the given planar stationary radiation source, the joint TDOA/FDOA location algorithm which solves the location of the target directly is proposed. Compared with weighted least squares(WLS) methods,the proposed algorithm is also suitable for well-posed conditions,and gets rid of the dependence on the constraints of Earth's surface. First of all, the solution formulas are expressed by the radial range. Then substitute it into the equation of the radial range to figure out the radial range between the target and the reference station. Finally use the solution expression of the target location to estimate the location of the target accurately. The proposed algorithm solves the problem that WLS methods have a large positioning error when the number of observation stations is not over-determined. Simulation results show the effectiveness of the proposed algorithm, including effectively increasing the positioning accuracy and reducing the number of observatories. 展开更多
关键词 passive location joint time differences of arrival/frequency differences of arrival(TDOA/FDOA)location direct solution stationary emitter well-posed equations
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COMPARISON OF TDOA LOCATION ALGORITHMS WITH DIRECT SOLUTION METHOD 被引量:1
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作者 Li Chun Liu Congfeng Liao Guisheng 《Journal of Electronics(China)》 2011年第4期652-657,共6页
For Time Difference Of Arrival(TDOA) location based on multi-ground stations scene,two direct solution methods are proposed to solve the target position in TDOA location.Therein,the solving methods are realized in the... For Time Difference Of Arrival(TDOA) location based on multi-ground stations scene,two direct solution methods are proposed to solve the target position in TDOA location.Therein,the solving methods are realized in the rectangular and polar coordinates.On the condition of rectangular coordinates,first of all,it solves the radial range between the target and reference station,then cal-culates the location of the target.In the case of polar coordinates,the azimuth between the target and reference station is solved first,then the radial range between the target and reference station is figured out,finally the location of the target is obtained.Simultaneously,the simulation and comparison analysis are given in detail,and show that the polar solving method has the better fuzzy performance than that of rectangular coordinate. 展开更多
关键词 passive location Time Difference Of Arrival(TDOA) location Direct solution method
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Observability and estimability of passive radar with unknown illuminator states using different observations 被引量:1
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作者 JING Tong TIAN Wei +1 位作者 HUANG Gaoming PENG Huafu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第6期1193-1205,共13页
Most existing studies about passive radar systems are based on the already known illuminator of opportunity(IO)states.However,in practice,the receiver generally has little knowledge about the IO states.Little research... Most existing studies about passive radar systems are based on the already known illuminator of opportunity(IO)states.However,in practice,the receiver generally has little knowledge about the IO states.Little research has studied this problem.This paper analyzes the observability and estimability for passive radar systems with unknown IO states under three typical scenarios.Besides,the directions of high and low estimability with respect to various states are given.Moreover,two types of observations are taken into account.The effects of different observations on both observability and estimability are well analyzed.For the observability test,linear and nonlinear methods are considered,which proves that both tests are applicable to the system.Numerical simulations confirm the correctness of the theoretical analysis. 展开更多
关键词 passive radar passive coherent location(PCL) OBSERVABILITY ESTIMABILITY unknown illuminator states
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Simulation study of passive target motion analysis
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作者 HU Youfeng,JIAO Binli (Department of electronics Peking University, Beijing 100871, China) 《声学技术》 CSCD 2003年第z1期52-55,共4页
In this paper, the problem of underwater passive target motion analysis (TMA) in three dimensions is discussed using the measurements of passive bearings and elevation and frequency on the condition that acoustic sour... In this paper, the problem of underwater passive target motion analysis (TMA) in three dimensions is discussed using the measurements of passive bearings and elevation and frequency on the condition that acoustic source and observer are in different horizontal planes. Simulation results with both of the PLE (pseudo-linear estimation) and MLE (Maximum likelihood estimation) show that the TMA method is effective in oceanic environment. Its error covariance curves tend to its Cramer-Rao lower bounds. 展开更多
关键词 target motion analysis (TMA) passive location Cramer-Rao LOWER BOUND (CRLB)
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Overview of Distribution Network Fault Location
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作者 Hao Wu Jie Yang +1 位作者 Qiaomei Wang Leilei Chen 《Energy and Power Engineering》 2019年第5期209-219,共11页
According to the existing research, the fault section location and fault location of passive distribution network and active distribution network are reviewed. Among them, fault location of passive distribution networ... According to the existing research, the fault section location and fault location of passive distribution network and active distribution network are reviewed. Among them, fault location of passive distribution network mainly introduces fault segment location based on transient state and steady state quantity and fault location based on transient quantity. The active distribution network mainly introduces the fault segment location based on the current amount and the switching capacity based on the distribution network topology. On this basis, the difficulties of fault location in the distribution network at present are analyzed, and the future development is prospected. 展开更多
关键词 passive DISTRIBUTION NETWORK Active DISTRIBUTION NETWORK SEGMENT Loca-tion Fault location Research and PROSPECT
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Passive Intermodulation Measurement:Challenges and Solutions
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作者 Zhanghua Cai Lie Liu +1 位作者 Francesco de Paulis Yihong Qi 《Engineering》 SCIE EI CAS 2022年第7期181-191,共11页
In modern wireless communication systems,the signal-to-noise ratio(SNR)is one of the most important performance indicators.When the other radio frequency(RF)performance of the components is well designed,passive inter... In modern wireless communication systems,the signal-to-noise ratio(SNR)is one of the most important performance indicators.When the other radio frequency(RF)performance of the components is well designed,passive intermodulation(PIM)interference may become an important factor limiting the system’s SNR.Whether it is a base station,an indoor distributed antenna system,or a satellite system,there are stringent PIM level requirements to minimize interference and enhance network capacity in multicarrier networks.Especially for systems of high power and wide bandwidth such as 5G wireless communication,PIM interference is even more serious.Due to the complexity and uncertainty of PIM,measurement is the most important means to study and evaluate the PIM performance of wireless communication systems.In this review,the current main PIM measurement methods recommended by International Electrotechnical Commission(IEC)and other standard organizations are introduced,and several key challenges in PIM measurement and their solutions(including the design of PIM tester,the location of the PIM sources,the design of compact PIM anechoic chambers,and the evaluation methods of PIM anechoic chambers)are highlighted.These challenges are of great significance to solve PIM problems that may arise during device characterization and verification in real wireless communication systems. 展开更多
关键词 passive intermodulation(PIM) PIM source location Anechoic chamber
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一种长基线被动传感器数据关联方法
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作者 白晶 《空天预警研究学报》 CSCD 2024年第1期57-60,64,共5页
为了提高测向交叉定位系统多目标环境下的去鬼点性能,提出了一种长基线被动传感器数据关联方法.首先利用被动传感器量测的视线矢量信息进行交叉定位并计算定位误差协方差矩阵,然后基于两个定位点构造了一个卡方分布的检验统计量,将多目... 为了提高测向交叉定位系统多目标环境下的去鬼点性能,提出了一种长基线被动传感器数据关联方法.首先利用被动传感器量测的视线矢量信息进行交叉定位并计算定位误差协方差矩阵,然后基于两个定位点构造了一个卡方分布的检验统计量,将多目标条件下的去鬼点问题转换为假设检验问题.为了分析该方法的性能,定义了真实目标的正确关联概率和鬼点目标的错误关联概率,并在使用两部和三部被动雷达的情况下分别与倾斜角方法进行了仿真对比.仿真结果表明所提出的方法在使用三部被动雷达或多目标与被动雷达共面时关联性能更好. 展开更多
关键词 被动传感器 长基线 数据关联 去鬼点 测向交叉定位 倾斜角
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非合作线谱声源分布式定位方法
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作者 邹男 于金正 +4 位作者 桑志远 李娜 苏薪元 杨嘉轩 惠云梦 《应用声学》 CSCD 北大核心 2024年第3期654-660,共7页
非合作目标定位是水声定位领域的研究热点。为充分挖掘并利用各类可观测参数,提高非合作目标定位能力,提出一种基于目标频率变化信息的非合作目标定位方法。该方法针对匀速直线运动目标的定位问题,首先根据多普勒频移原理,建立观测频率... 非合作目标定位是水声定位领域的研究热点。为充分挖掘并利用各类可观测参数,提高非合作目标定位能力,提出一种基于目标频率变化信息的非合作目标定位方法。该方法针对匀速直线运动目标的定位问题,首先根据多普勒频移原理,建立观测频率与目标辐射频率、目标运动速度、位置之间的函数映射关系,利用最小均方准则建立目标函数,通过优化算法估计分布式定位系统中各个测量单元与目标运动轨迹的致近点距离,最后综合各观测节点的测距结果,构建几何定位模型,求得目标运动轨迹的解析解。通过仿真分析,证明了该方法的有效性,并指出了该方法需要目标通过与各测量单元的致近点才能获得较好的距离估计能力。文中分析了不同频率估计精度对定位精度的影响,结果表明,提出的定位方法对测频精度具有一定的容限,是一种高精度的非合作线谱声源定位方法。 展开更多
关键词 非合作定位 被动定位 信赖域优化方法 被动测距 目标运动分析
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基于PSD传感器的炸点三维坐标测量方法研究
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作者 宁威 褚文博 +1 位作者 张斌 赵冬娥 《计算机测量与控制》 2024年第3期195-203,共9页
针对野外炸点空间三维坐标测量的问题,提出了基于二维PSD位置传感器的炸点位置测量方法,构建了基于二维PSD位置传感器的炸点三维坐标测量系统;基于双目视觉原理建立了炸点空间三维坐标测量数学模型;研究了被动探测系统在野外远距离下的... 针对野外炸点空间三维坐标测量的问题,提出了基于二维PSD位置传感器的炸点位置测量方法,构建了基于二维PSD位置传感器的炸点三维坐标测量系统;基于双目视觉原理建立了炸点空间三维坐标测量数学模型;研究了被动探测系统在野外远距离下的标定技术;通过系统误差分解传递,分析了各参数的误差;在Matlab中分别绘制了炸点位置坐标3个维度的误差分布图,并分析了测量系统误差随炸点实际位置变化的分布情况;根据误差分布图得到了在理论100 m测试距离下X坐标最大测量误差约为0.292~0.303 m,Y坐标最大测量误差约为0.251~0.371 m,Z坐标最大测量误差0.270~0.336 m;最后通过静爆实验对测量方法正确性、被动探测系统标定技术可行性和测量系统功能性进行了验证,结果表明测量系统响应速度快且功能正常,被动探测系统标定技术具备可行性且操作方便,可适用于野外炸点位置的快速测量。 展开更多
关键词 PSD位置传感器 炸点位置测量 双目视觉原理 被动探测标定 误差分析
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