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Application of 3-D Geoscience Modeling Technology for the Estimation of Solid Mineral Reserves 被引量:15
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作者 PAN Mao LI Jun +1 位作者 WANG Zhangang JIN Jiangjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第3期655-660,共6页
Applying new approaches, methods, and technologies for the estimation of reserves can effectively improve the efficiency and accuracy of assessments of solid mineral resources. After analyzing the development of 3-D g... Applying new approaches, methods, and technologies for the estimation of reserves can effectively improve the efficiency and accuracy of assessments of solid mineral resources. After analyzing the development of 3-D geoscience modeling technology (3-D GMT), this paper discusses the application of 3-D GMT for the estimation of solid mineral reserves, emphatically introducing its workflow and two key technologies, 3-D orebody surface modeling, and property modeling. Moreover, the paper analyzes the limitations of traditional methods, such as the section method and geological block method, and points out the advantages of 3-D GMT: building more accurate 3-D orebody models, expressing the internal inhomogeneous attributes of an orebody, reducing the potential for errors in the estimation of reserves, and implementing dynamic estimations of reserves. 展开更多
关键词 3-d geoscience modeling solid mineral resource estimation of reserves surface modeling property modeling
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EFFECT OF SUBMERGED ENTRY NOZZLE (SEN) PARAMETERS AND SHAPE ON 3-D FLUID FLOW IN MOULD FOR BEAM BLANK CONTINUOUS CASTING
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作者 Y.P.Du J.W.Yang +1 位作者 R.Shi X.C.Cui 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2004年第5期705-712,共8页
According to turbulent theory and characteristics of beam blank continuous casting, 3-D model to represent the flow of beam blank mould is established. The predicted results indicate that the exit obliquity of up 15&#... According to turbulent theory and characteristics of beam blank continuous casting, 3-D model to represent the flow of beam blank mould is established. The predicted results indicate that the exit obliquity of up 15°(+15°) should be adopted, which will benefit the floatation of non-metallic inclusion and purification of the molten steel. When the nozzle angle is 120°, the flow pattern is reasonable. Proper nozzle depth can be 200mm. Turbulent kinetic of meniscus can be reduced by adopting the square nozzle and suitable area of side outlet when casting speed increases. The results are consistent with those of water model experiment, so the model is exact and reasonable. The model can provide important information for design of SEN and defining of immersion depth. 展开更多
关键词 SEN parameter SEN shape beam blank continuous casting 3-d flow distribution turbulent kinetic energy
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An Experimental System Development for Head Posture Estimation Based on 3-D Images Measurement
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作者 Chen Xu Cunwei Lu 《Journal of Computer and Communications》 2014年第2期57-63,共7页
Although automobile is an indispensable vehicle to modern life, it also serves as a social problem with a big traffic accident. Among the reasons of traffic accidents, careless driving accounts for the largest part. S... Although automobile is an indispensable vehicle to modern life, it also serves as a social problem with a big traffic accident. Among the reasons of traffic accidents, careless driving accounts for the largest part. So in order to avoid the careless driving, a system which can measure the posture of a driver and warns driver to drive carefully in the case of looking aside is necessary. Although the image measurement method is used broadly, there is a problem on which measurement accuracy is influenced by environment light, makeup of the driver, etc. in the general method based on the two-dimensional image. Therefore, in this study, we propose an image measurement method to obtain the head posture of driver. First we use three-dimensional measurement method which based on the infrared pattern projection to get 3-D information of head, and then we calculate the angle for faces. In this paper, we explain the composition method of an experiment system, and the results of head posture measurement experiment. 展开更多
关键词 Careless Driving 3-d Image MEASUREMENT INFRARED Pattern PROJECTION Head POSTURE estimation
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顾及电离层延迟的BDS-3四频长基线定位算法 被引量:1
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作者 吕震 王振杰 +2 位作者 刘金萍 翟建朋 周浩 《测绘通报》 CSCD 北大核心 2023年第4期71-74,75-78,共8页
针对长基线定位中电离层延迟对定位精度造成的影响,本文提出了一种基于BDS-3四频信号(B1C/B1I/B2a/B3I)的四频消电离层(IF)组合方法,采用消电离层组合观测值消除电离层延迟误差,联合模糊度改正后的超宽巷或宽巷组合观测值构建定位方程,... 针对长基线定位中电离层延迟对定位精度造成的影响,本文提出了一种基于BDS-3四频信号(B1C/B1I/B2a/B3I)的四频消电离层(IF)组合方法,采用消电离层组合观测值消除电离层延迟误差,联合模糊度改正后的超宽巷或宽巷组合观测值构建定位方程,从而实现原始窄巷模糊度和基线位置坐标的解算。试验采用BDS-3四频数据对四频IF组合方法和基于GB-FCAR模型的电离层延迟参数估计方法的定位精度进行对比分析。结果表明,在对长度超过500 km的长基线进行定位解算时,四频IF组合方法可以实现电离层延迟误差消除。与电离层延迟参数估计方法相比,四频IF组合方法水平和垂直方向的定位精度均达分米级,提升幅度分别达35%和40%以上,定位精度显著提高,其相对定位精度可达1×10^(-9)m,满足长基线相对定位的要求。 展开更多
关键词 BDS-3 四频 长基线 参数估计 消电离层组合
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Depth estimation system suitable for hardware design
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作者 李贺建 左一帆 +3 位作者 杨高波 安平 王建伟 滕国伟 《Journal of Shanghai University(English Edition)》 CAS 2011年第4期325-330,共6页
Depth estimation is an active research area with the developing of stereo vision in recent years. It is one of the key technologies to resolve the large data of stereo vision communication. Now depth estimation still ... Depth estimation is an active research area with the developing of stereo vision in recent years. It is one of the key technologies to resolve the large data of stereo vision communication. Now depth estimation still has some problems, such as occlusion, fuzzy edge, real-time processing, etc. Many algorithms have been proposed base on software, however the performance of the computer configurations limits the software processing speed. The other resolution is hardware design and the great developments of the digital signal processor (DSP), and application specific integrated circuit (ASIC) and field programmable gate array (FPGA) provide the opportunity of flexible applications. In this work, by analyzing the procedures of depth estimation, the proper algorithms which can be used in hardware design to execute real-time depth estimation are proposed. The different methods of calibration, matching and post-processing are analyzed based on the hardware design requirements. At last some tests for the algorithm have been analyzed. The results show that the algorithms proposed for hardware design can provide credited depth map for further view synthesis and are suitable for hardware design. 展开更多
关键词 3-d TV 3DTV) depth estimation hardware design rank transform census transform
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结合先验概率估计的GF-3影像水体概率估计方法 被引量:4
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作者 孟令奎 毛旭东 +1 位作者 魏祖帅 张文 《测绘学报》 EI CSCD 北大核心 2019年第4期439-447,共9页
综合SAR(synthetic aperture radar)影像的统计模型假设与k-means聚类算法,提出了一种结合水体分布先验概率估计的水体概率估计方法。首先,用贝叶斯推断对研究区域后向散射系数做统计模型假设。随后,结合聚类算法对像元作分类,估计水体... 综合SAR(synthetic aperture radar)影像的统计模型假设与k-means聚类算法,提出了一种结合水体分布先验概率估计的水体概率估计方法。首先,用贝叶斯推断对研究区域后向散射系数做统计模型假设。随后,结合聚类算法对像元作分类,估计水体分布先验概率,结合统计分布直方图使用非线性最小二乘拟合完成模型参数估计。试验选取了高分三号(GF-3)多种工作模式数据,并用高分一号(GF-1)影像进行验证。结果表明,该方法可有效实现SAR影像的高精度水体概率估计。 展开更多
关键词 水体概率估计 参数估计 合成孔径雷达(SAR) 高分三号
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Accurate 3D Thermal Network Development for Direct-drive Outer-rotor Hybrid-PM Flux-switching Generator
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作者 Ali Zarghani Mohammad Farahzadi +1 位作者 Aghil Ghaheri Karim Abbaszadeh 《Chinese Journal of Electrical Engineering》 EI CSCD 2024年第2期80-92,共13页
Heat and thermal problems are major obstacles to achieving high power density in compact permanent magnet(PM)topologies.Consequently,a comprehensive,accurate,and rapid temperature rise estimation method is required fo... Heat and thermal problems are major obstacles to achieving high power density in compact permanent magnet(PM)topologies.Consequently,a comprehensive,accurate,and rapid temperature rise estimation method is required for novel electric machines to ensure safe and reliable operations.A unique three-dimensional(3D)lumped parameter thermal network(LPTN)is presented for accurate thermal modeling of a newly developed outer-rotor hybrid-PM flux switching generator(OR-HPMFSG)for direct-drive applications.First,the losses of the OR-HPMFSG are calculated using 3D finite element analysis(FEA).Subsequently,all machine components considering the thermal contact resistance,anisotropic thermal conductivity of materials,and various heat flow paths are comprehensively modeled based on the thermal resistances.In the proposed 3-D LPTN,internal nodes are considered to predict the average temperature as well as the hot spots of all active and passive components.Experimental measurements are performed on a prototype OR-HPMFSG to validate the efficiency of the 3-D LPTN.A comparison of the results at various operating points between the developed 3-D LPTN,experimental test,and FEA indicates that the 3-D LPTN quickly approximates the hotspot and mean temperature of all components under both transient and steady states with high accuracy. 展开更多
关键词 Direct-drive wind turbine hybrid-PM flux switching generator lumped parameter thermal network temperature estimation 3D thermal modeling
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W-3参数方程组的数值解法
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作者 胡文忠 蔡志波 斑士欣 《气象学报》 CAS CSCD 北大核心 1998年第4期500-505,共6页
从W-3风频模型的期望值及其拟合误差出发,分别用矩法和极值法导出关于Weibul参数的两组方程。结合实测风况资料用数值法求解,获得相应的W-3风频参数,通过几个气象台站的实测资料计算、比较,证明这两种方法给出的参数其... 从W-3风频模型的期望值及其拟合误差出发,分别用矩法和极值法导出关于Weibul参数的两组方程。结合实测风况资料用数值法求解,获得相应的W-3风频参数,通过几个气象台站的实测资料计算、比较,证明这两种方法给出的参数其拟合精度均高于W-2模型给出的结果。 展开更多
关键词 W-3分布函数 参数估算 参数方程组 风场
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3-D VARIABLE PARAMETER NUMERICAL MODEL FOR EVALUATION OF THE PLANNED EXPLOITABLE GROUNDWATER RESOURCE IN RE-GIONAL UNCONSOLIDATED SEDIMENTS 被引量:5
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作者 LUO Zu-jiang WANG Yan 《Journal of Hydrodynamics》 SCIE EI CSCD 2012年第6期959-968,共10页
In order to correctly evaluate the exploitable groundwater resottrce in regional complex, thick Quaternary unconsolidated sediments, the whole Quaternary unconsolidated sediments are considered as a unified hydrogeolo... In order to correctly evaluate the exploitable groundwater resottrce in regional complex, thick Quaternary unconsolidated sediments, the whole Quaternary unconsolidated sediments are considered as a unified hydrogeological unit and a 3-D unsteady groundwater flow numerical model is adopted. Meanwhile, with the consideration of the dynamic changes of the porosity, the hydraulic conductivity and the specific storage with the groundwater level dropping during the exploitation process, an improved composite element seepage matrix adjustment method is applied to solve the unsteady flow problem of free surface. In order to eva- luate the exploitable groundwater resource in Cangzhou, Hebei Province, the hydrogeological conceptual model of Cangzhou is generalized to establish, a 3-D variable parameter numerical model of Cangzhou. Based on the prediction of the present groundwater exploitation, and by adjusting the groundwater exploitation layout, the exploitable groundwater resource is predicted. The model enjoys features like good convergence, good stability and high precision. 展开更多
关键词 exploitable quantity of groundwater resource variable parameters free surface 3-d numerical model
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Two-Dimensional Interpolation Criterion Using DFT Coefficients
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作者 Yuan Chen Liangtao Duan +1 位作者 Weize Sun Jingxin Xu 《Computers, Materials & Continua》 SCIE EI 2020年第2期849-859,共11页
In this paper,we address the frequency estimator for 2-dimensional(2-D)complex sinusoids in the presence of white Gaussian noise.With the use of the sinc function model of the discrete Fourier transform(DFT)coefficien... In this paper,we address the frequency estimator for 2-dimensional(2-D)complex sinusoids in the presence of white Gaussian noise.With the use of the sinc function model of the discrete Fourier transform(DFT)coefficients on the input data,a fast and accurate frequency estimator is devised,where only the DFT coefficient with the highest magnitude and its four neighbors are required.Variance analysis is also included to investigate the accuracy of the proposed algorithm.Simulation results are conducted to demonstrate the superiority of the developed scheme,in terms of the estimation performance and computational complexity. 展开更多
关键词 2-d Frequency estimation parameter estimation INTERPOLATION discrete Fourier transform
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Semi-Global Depth Estimation Algorithm for Mobile 3-D Video Applications
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作者 Qiong Liu Hongjiang Xiao 《Tsinghua Science and Technology》 EI CAS 2012年第2期128-135,共8页
Three-dimensional (3-D) video applications, such as 3-D cinema, 3DTV, ana Free Viewpomt Video (FVV) are attracting more attention both from the industry and in the literature. High accuracy of depth video is a fun... Three-dimensional (3-D) video applications, such as 3-D cinema, 3DTV, ana Free Viewpomt Video (FVV) are attracting more attention both from the industry and in the literature. High accuracy of depth video is a fundamental prerequisite for most 3-D applications. However, accurate depth requires computationally intensive global optimization. This high computational complexity is one of the bottlenecks to applying depth generation to 3-D applications, especially for mobile networks since mobile terminals usually have limited computing ability. This paper presents a semi-global depth estimation algorithm based on temporal consis- tency, where the depth propagation is used to generate initial depth values for the computationally intensive global optimization. The accuracy of initial depth is improved by detecting and eliminating the depth propagation outliers before the global optimization. Integrating the initial values without outliers into the global optimization reduces the computational complexity while maintaining the depth accuracy. Tests demonstrate that the algorithm reduces the total computational time by 54%-65% while the quality of the virtual views is essentially equivalent to the benchmark. 展开更多
关键词 3-d video depth estimation temporal propagation graph cuts
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基于参数估计误差的鲁棒自适应律设计及验证 被引量:9
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作者 那靖 杨光宇 +1 位作者 高贯斌 张金岗 《控制理论与应用》 EI CAS CSCD 北大核心 2016年第7期956-964,共9页
针对传统自适应控制系统设计的自适应律参数收敛慢进而影响控制系统瞬态性能的问题,研究一类新的基于参数估计误差修正的鲁棒自适应律设计.首先引入滤波操作给出参数估计误差的提取方法,构建出含参数估计误差修正项的自适应律,进而将该... 针对传统自适应控制系统设计的自适应律参数收敛慢进而影响控制系统瞬态性能的问题,研究一类新的基于参数估计误差修正的鲁棒自适应律设计.首先引入滤波操作给出参数估计误差的提取方法,构建出含参数估计误差修正项的自适应律,进而将该自适应律用于控制器设计和分析中,可同时实现控制误差和参数估计误差指数收敛.对比分析了几类传统自适应律和所提出自适应律的收敛性和鲁棒性,并给出了保证参数收敛所需持续激励条件的一种直观、简便的在线判别方法.数值仿真及基于自制三自由度直升机系统俯仰轴实验结果表明,基于参数误差修正的自适应律及控制器可得到优于传统自适应方法的跟踪控制和参数估计性能. 展开更多
关键词 自适应控制 参数估计 非线性系统 三自由度直升机
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三参数威布尔分布参数估计方法比较 被引量:58
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作者 严晓东 马翔 +1 位作者 郑荣跃 吴亮 《宁波大学学报(理工版)》 CAS 2005年第3期301-305,共5页
选择目前常用的5种三参数威布尔分布参数估计法(概率权重矩法、极大似然法、双线性回归法、相关系数优化法、灰色估计法)进行比较研究,采用不同样本的7组数据进行参数估计,得出了这5种方法各自相应的适用范围,相关结论对正确选用三参数... 选择目前常用的5种三参数威布尔分布参数估计法(概率权重矩法、极大似然法、双线性回归法、相关系数优化法、灰色估计法)进行比较研究,采用不同样本的7组数据进行参数估计,得出了这5种方法各自相应的适用范围,相关结论对正确选用三参数威布尔分布参数求解方法有一定指导意义. 展开更多
关键词 三参数威布尔分布 极大似然法 双线性回归法 概率权重矩法 相关系数优化法 灰色估计法
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利用三角剖分算法进行小天体物理属性计算 被引量:4
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作者 邵巍 崔平远 崔祜涛 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2010年第5期687-691,共5页
提出了一种利用三维散乱点对小天体表面进行三角剖分,并对小天体的多个物理属性进行估计的简单快速算法.先将小天体表面的散乱点映射到单位球面上,再进一步映射到平面上进行三角网格剖分,避免了非凸边界对原有拓扑结构的破坏.在形成三... 提出了一种利用三维散乱点对小天体表面进行三角剖分,并对小天体的多个物理属性进行估计的简单快速算法.先将小天体表面的散乱点映射到单位球面上,再进一步映射到平面上进行三角网格剖分,避免了非凸边界对原有拓扑结构的破坏.在形成三角网格的基础上,将对体积的积分转化为对多面体顶点坐标的计算,并采用分割小四面体的算法简化了利用格林公式进行多次积分转化的计算过程,从而求出小天体的体积、表面积、质心、转动惯量、惯量主轴及其引力势、引力场分布等多个重要的物理量.通过仿真分析了散乱点数目对计算精度的影响,验证了该算法的正确性. 展开更多
关键词 小天体 三维散乱点 三角剖分 体积积分 物理参数估计 格林公式
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基于最小能量准则的参数估计圆周SAR三维成像方法 被引量:4
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作者 王保平 马健钧 +1 位作者 张研 方阳 《红外与激光工程》 EI CSCD 北大核心 2019年第7期272-278,共7页
针对圆周合成孔径雷达成像模式下应用参数化估计的三维成像算法效率低、精度差的问题,提出一种基于最小能量准则的参数估计圆周SAR三维成像算法。该算法首先对成像场景进行粗略网格划分,利用参数估计的方法得到目标的粗略位置,其次利用... 针对圆周合成孔径雷达成像模式下应用参数化估计的三维成像算法效率低、精度差的问题,提出一种基于最小能量准则的参数估计圆周SAR三维成像算法。该算法首先对成像场景进行粗略网格划分,利用参数估计的方法得到目标的粗略位置,其次利用最小能量准则和精细化网格的方法得到目标精确三维位置和散射强度系数,最后通过CLEAN技术消除已估计点带来的影响,实现场景的三维成像。仿真实验结果表明:所提成像方法能有效对圆周观测下目标进行三维成像,同时与传统算法相比,解决了传统算法效率低、对目标估计不准确的问题,验证了所提算法的有效性。 展开更多
关键词 圆周SAR 参数估计 最小能量准则 三维成像
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基于微动参数估计的非对称进动目标三维成像 被引量:2
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作者 胡晓伟 童宁宁 +2 位作者 何兴宇 江东 王宇晨 《系统工程与电子技术》 EI CSCD 北大核心 2016年第3期501-505,共5页
具有非对称结构的进动目标成像是目前空间目标成像的一个难点。在构建非对称进动目标回波模型的基础上,分析了成像所需的4个微动参数并给出了相应的参数估计方法。在微动参数已知的前提下,提出了一种基于三维复数逆投影变换的进动目标... 具有非对称结构的进动目标成像是目前空间目标成像的一个难点。在构建非对称进动目标回波模型的基础上,分析了成像所需的4个微动参数并给出了相应的参数估计方法。在微动参数已知的前提下,提出了一种基于三维复数逆投影变换的进动目标三维成像的方法。首先利用微动参数构建相位补偿因子,之后对时间距离像进行三维搜索,进而实现进动目标的三维成像。最后通过仿真实验验证了所提方法的有效性,同时仿真分析了微动参数估计误差对成像的影响。 展开更多
关键词 非对称进动目标 微动参数估计 三维复数逆投影 三维成像
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基于遗传算法的设计波浪要素推算 被引量:3
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作者 陈同庆 张庆河 丁磊 《港工技术》 北大核心 2006年第3期1-3,共3页
利用遗传算法对P-Ⅲ型分布曲线进行参数估计,论证了包括均值、离差系数和偏态系数的三参数优化方法优于只求解离差系数和偏态系数的两参数优化方法。对于含历史特大值的不连续数据序列,建议采取加权适线的曲线拟合方法。基于遗传算法M a... 利用遗传算法对P-Ⅲ型分布曲线进行参数估计,论证了包括均值、离差系数和偏态系数的三参数优化方法优于只求解离差系数和偏态系数的两参数优化方法。对于含历史特大值的不连续数据序列,建议采取加权适线的曲线拟合方法。基于遗传算法M atlab工具箱设计了用于P-Ⅲ型分布参数估计和设计波浪要素推算的程序。 展开更多
关键词 设计波浪要素推算 P-Ⅲ分布曲线 参数估计 遗传算法 加权
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宽频段相干信号三维参数联合估计的新算法 被引量:1
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作者 杜刚 姜新迎 +1 位作者 王永良 张永顺 《信号处理》 CSCD 北大核心 2008年第6期908-911,共4页
基于非均匀的L型阵列,本文提出了一种宽频段相干信号频率和二维到达角联合估计的时空二维处理新方B法—WTSS(wide-band time-space smoothing)算法。该算法能精确地估计具有相同数字频率的相干信号的三维参数,无需多维谱峰搜索,具有计... 基于非均匀的L型阵列,本文提出了一种宽频段相干信号频率和二维到达角联合估计的时空二维处理新方B法—WTSS(wide-band time-space smoothing)算法。该算法能精确地估计具有相同数字频率的相干信号的三维参数,无需多维谱峰搜索,具有计算量小,参数自动配对的优点。另外,在WTSS算法的基础上,利用L型阵列的特点进行分维处理,成功地实现了具有频率兼并现象的相干信号的三维参数估计。该算法能够并行实现以进一步增强其实时性。计算机仿真结果验证了算法的有效性。 展开更多
关键词 宽频段 相干源 三维参数估计 平滑技术
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宽频段空间相干信号三维参数联合估计算法 被引量:1
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作者 杜刚 张永顺 姜新迎 《空军工程大学学报(自然科学版)》 CSCD 北大核心 2008年第2期36-38,91,共4页
基于非均匀的L型阵列,提出一种宽频段相干信号频率和二维到达角联合估计的新方法——JSDOA算法。该算法利用阵列时空数据构造了一个平滑的波达矩阵,通过对其进行特征分解估计出相干信号的三维参数。该算法能精确地估计具有相同数字频率... 基于非均匀的L型阵列,提出一种宽频段相干信号频率和二维到达角联合估计的新方法——JSDOA算法。该算法利用阵列时空数据构造了一个平滑的波达矩阵,通过对其进行特征分解估计出相干信号的三维参数。该算法能精确地估计具有相同数字频率的相干信号的三维参数,避免了阵列孔径损失,具有计算量小,三维参数自动配对的优点。计算机仿真结果验证了算法的有效性。 展开更多
关键词 宽频段 相干源 三维参数估计 平滑技术
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随机截尾寿命试验工参数Weibull分布的统计分析 被引量:5
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作者 师义民 杨昭军 《西北大学学报(自然科学版)》 CAS CSCD 1996年第4期285-288,共4页
利用随机截尾寿命试验获得的数据,给出了三参数Weibull分布参数,可靠度和失效率的Bayes点估计及其置信限。
关键词 随机截尾试验 贝叶斯估计 寿命试验 韦伯分布
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