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Three-dimensional coordinates test method with uncertain projectile proximity explosion position based on dynamic seven photoelectric detection screen 被引量:2
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作者 Han-shan Li Xiao-qian Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第9期1643-1652,共10页
To objectively obtain the three-dimensional coordinates of the projectile fuze proximity explosion when projectile intersects the head of missile target, we propose a dynamic seven photoelectric detection screen test ... To objectively obtain the three-dimensional coordinates of the projectile fuze proximity explosion when projectile intersects the head of missile target, we propose a dynamic seven photoelectric detection screen test method, which is made up of six plane detection screens and a flash photoelectric dynamic detection screen. The three-dimensional coordinates calculation model of the projectile proximity explosion position based on seven plane detection screens with dynamic characteristics is established.According to the relation of the dynamic seven photoelectric detection screen planes and the time values,the analytical function of the projectile proximity explosion position parameters under non-linear motion is derived. The projectile signal filtering method based on discrete wavelet transform is explored in this work. Additionally, the projectile signal recognition algorithm using an improved particle swarm is proposed. Based on the characteristics of the time duration and the signal peak error for the projectile passing through the detection screen, the signals attribution of the same projectile passing through six detection screens are analyzed for obtaining precise time values of the same projectile passing through the detection screens. On the basis of the projectile fuze proximity explosion test, the linear motion model and the proposed non-linear motion model are used to calculate and compare the same group of projectiles proximity explosion position parameters. The comparison of test results verifies that the proposed test method and calculation model in this work accurately obtain the actual projectile proximity explosion position parameters. 展开更多
关键词 Dynamic multi-screen array plane Flash photoelectric detection target Projectile signal processing Particle swarm Proximity explosion fuze three-dimensional coordinate
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Three-dimensional stability calculation method for high and large composite slopes formed by mining stope and inner dump in adjacent open pits
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作者 Zuchao Liang Dong Wang +4 位作者 Guanghe Li Guangyu Sun Mingyu Yu Dong Xia Chunjian Ding 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期507-520,共14页
The 2D limit equilibrium method is widely used for slope stability analysis.However,with the advancement of dump engineering,composite slopes often exhibit significant 3D mechanical effects.Consequently,it is of signi... The 2D limit equilibrium method is widely used for slope stability analysis.However,with the advancement of dump engineering,composite slopes often exhibit significant 3D mechanical effects.Consequently,it is of significant importance to develop an effective 3D stability calculation method for composite slopes to enhance the design and stability control of open-pit slope engineering.Using the composite slope formed by the mining stope and inner dump in Baiyinhua No.1 and No.2 open-pit coal mine as a case study,this research investigates the failure mode of composite slopes and establishes spatial shape equations for the sliding mass.By integrating the shear resistance and sliding force of each row of microstrip columns onto the bottom surface of the strip corresponding to the main sliding surface,a novel 2D equivalent physical and mechanical parameters analysis method for the strips on the main sliding surface of 3D sliding masses is proposed.Subsequently,a comprehensive 3D stability calculation method for composite slopes is developed,and the quantitative relationship between the coordinated development distance and its 3D stability coefficients is examined.The analysis reveals that the failure mode of the composite slope is characterized by cutting-bedding sliding,with the arc serving as the side interface and the weak layer as the bottom interface,while the destabilization mechanism primarily involves shear failure.The spatial form equation of the sliding mass comprises an ellipsoid and weak plane equation.The analysis revealed that when the coordinated development distance is 1500 m,the error rate between the 3D stability calculation result and the 2D stability calculation result of the composite slope is less than 8%,thereby verifying the proposed analytical method of equivalent physical and mechanical parameters and the 3D stability calculation method for composite slopes.Furthermore,the3D stability coefficient of the composite slope exhibits an exponential correlation with the coordinated development distance,with the coefficient gradually decreasing as the coordinated development distance increases.These findings provide a theoretical guideline for designing similar slope shape parameters and conducting stability analysis. 展开更多
关键词 Composite slope Destabilization mechanism 3D mechanical effect three-dimensional stability coordinated development distance
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Risk Assessment of Coal Mine Water Hazard Based on Three-Dimensional Model of Geology and Underground Space 被引量:1
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作者 Kai Zhang~1,Ming Huang~1,Bin Tang~2,Fan Cui~1 1.Laboratory of Coal Resources and Mine Safety,China University of Mining and Technology,Beijing 100083,China. 2.China Water Investment Co.Ltd,Beijing 100053,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期279-279,共1页
Mine safety have top-five disasters,which including the water,gas,fire,dust and geological dynamic disaster.The coal mine water disaster is one of the important factors which restricted the development of China’s coa... Mine safety have top-five disasters,which including the water,gas,fire,dust and geological dynamic disaster.The coal mine water disaster is one of the important factors which restricted the development of China’s coal production.It is showed by statistics that 60%of mine accidents are affected by groundwater,which not only result in the production losses,casualties and a variety of 展开更多
关键词 DISASTER risk assessment three-dimensional model of GEOLOGY and UNDERGROUND space emergency RESCUE
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Interconverting Models of Gray Matrix and Geographic Coordinates Based on Space Analytic Geometry 被引量:1
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作者 Ni Zhan Liang Lin Ling Lou 《Applied Mathematics》 2013年第1期46-51,共6页
With the progress and development of science, the synchronous satellite as the high-tech product is taken something more and more seriously by all countries. Converting gray value matrix into geographic coordinates be... With the progress and development of science, the synchronous satellite as the high-tech product is taken something more and more seriously by all countries. Converting gray value matrix into geographic coordinates becomes more and more important. This paper establishes the models for interconverting row and column of gray value matrix which detected by the infrared detectors on synchronous satellites and geographic coordinates based on the related theorems and properties of space analytic geometry. We draw satellite cloud image with the data of gray matrix in MATLAB, convert coastline’s latitude and longitude coordinates into row and column coordinates of a gray matrix according via these models when the sub-satellite point’s row and column coordinates and geographic coordinates are given, then add coast-lines to the original satellite cloud image with the transformation data. We find that coast-lines completely match with the bump characteristics of satellite cloud image, and that verify the correctness of the models. 展开更多
关键词 space ANALYTIC Geometry Satellite Cloud Image GEOGRAPHIC coordinates GRAY Value MATRIX COASTLINE
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Three-dimensionally ordered macroporous cross-linked polystyrene incorporating functional group via hydrophilic spacer arm 被引量:1
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作者 Li Xia Yuan Xiao Mei Wang Xu Zhang Pan Ge Liu Wei Dong Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第12期1493-1496,共4页
A versatile and effective method for incorporating functional groups on the pore wall of three-dimensionally ordered macroporous cross-linked polystyrene(3DOM CLPS) by hydrophilic spacer arm has been investigated.Th... A versatile and effective method for incorporating functional groups on the pore wall of three-dimensionally ordered macroporous cross-linked polystyrene(3DOM CLPS) by hydrophilic spacer arm has been investigated.The 3DOM CLPS with pore size 865 nm was prepared by sacrifice template method.The hydrophilic spacer arm(polyethylene glycol,molecular weight is 600) was grafted to the 3DOM CLPS via nucleophilic substitution reaction.The other side of active hydroxyl can be further converted into a lot of other functional groups.In this report,the chelating ligand 2-mercaptobenzothiazole(MBZ) group was introduced on the end of the PGE chain to evidence the versatile functionalization approach.The functionalized ordered macroporous materials were characterized by FT-IR,element analyzer,SEM.The results reveal that the pores were successfully bonded with 2-mercaptobenzothiazole groups via hydrophilic spacer arms and the original morphology of ordered macroporous materials were remained after functionalization.The MBZ group density is 0.052 mmol/m^2.The functionalized 3DOM CLPS are expected to application as heavy metal ions adsorbent. 展开更多
关键词 three-dimensionally ordered macroporous polymer FUNCTIONALIZATION Hydrophilic space arm Heterocyclic functional group
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Continuous imaging space in three-dimensional integral imaging 被引量:1
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作者 张雷 杨勇 +3 位作者 王金刚 赵星 方志良 袁小聪 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期303-305,共3页
We report an integral imaging method with continuous imaging space. This method simultaneously reconstructs real and virtual images in the virtual mode, with a minimum gap that separates the entire imaging space into ... We report an integral imaging method with continuous imaging space. This method simultaneously reconstructs real and virtual images in the virtual mode, with a minimum gap that separates the entire imaging space into real and virtual space. Experimental results show that the gap is reduced to 45% of that in a conventional integral imaging system with the same parameters. 展开更多
关键词 three-dimensional integral imaging imaging space
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Using"Three-dimensional Space Resources"for Fenlong Technology to Improve Grain Econoloy and Expand Human Living Spaces 被引量:1
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作者 Benhui WEI 《Asian Agricultural Research》 2020年第12期32-38,共7页
Fenlong Technology has been applied to increase yield by 20%-50%,improve quality by 5%,and retain water by 100%in 40 kinds of crop cultivated land and saline-alkali land in 26 provinces of China.This paper clarified f... Fenlong Technology has been applied to increase yield by 20%-50%,improve quality by 5%,and retain water by 100%in 40 kinds of crop cultivated land and saline-alkali land in 26 provinces of China.This paper clarified for the first time the scientific theory system of Fenlong Technology using three-dimensional space resources"Fenlong Agricultural Nature Theory"and the development of the relative"limits"of agricultural growth,which provides a huge power support and natural force for expanding human living spaces.Through inventing and creating a scientific and technological system of farming tools,farming machinery,farming modes,and magic weapons for cultivation,Fenlong Technology can increase grain,promote ecological development,and greatly expand the living spaces of the Chinese nation and achieve sustainable development.Using Fenlong Technology,China has expanded from the current single"cultivated land agriculture"to the"big pattern agriculture"of Fenlong"cultivated land+saline land+degraded grassland+marginal land+desertified land+river water",flexibly used 147 million ha of"three-dimensional space resources"of land,and the newly increased food,meat,and fish can feed 300 million to 400 million people,increased the water storage by 100 billion m^(3),and reduced the collection of groundwater by 20 million to 60 billion m^(3). 展开更多
关键词 three-dimensional space resources Fenlong Agricultural Nature Theory Relative"limits" Expanding the living spaces Improving the grain ecology Fenlong farming
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Synthesis and Crystal Structure of a Three-dimensional Mn(Ⅱ) Coordination Polymer with 3-(Pyrazin-2-yloxy)-pyridine and Azide Anion as Mixed Bridge Ligand 被引量:1
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作者 李红 赵红艳 +1 位作者 张士国 石敬民 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第12期1511-1513,共3页
A three-dimensional coordination polymer [Mn2(μ1.3-N3)4(μ-PP)2]n (PP = 3-(pyrazin-2-yloxy)-pyridine) has been synthesized with 3-(pyrazin-2-yloxy)-pyridine and azide anion as mixed bridge ligand, and its c... A three-dimensional coordination polymer [Mn2(μ1.3-N3)4(μ-PP)2]n (PP = 3-(pyrazin-2-yloxy)-pyridine) has been synthesized with 3-(pyrazin-2-yloxy)-pyridine and azide anion as mixed bridge ligand, and its crystal structure was determined by X-ray crystallography. The crystal data: triclinic system, space group P1, with a = 6.794(4), b = 9.885(6), c = 9.947(6) A, α = 64.170(6), β= 84.190(8), γ= 85.319(8)°, V = 597.7(6)A^3, Z = 1, C18H14Mn2N18O2, Mr = 624.35, Dc = 1.735 g/cm^3, F(000) = 314 and μ = 1.117 mm^-1. In the crystal, the azide anion acts as a bridge ligand and makes adjacent Mn(Ⅱ) ions connect into a two-dimensional sheet on the ab plane, then 3-(pyrazin-2-yloxy)-pyridine serves as a bidentate bridge ligand to connect neighboring sheets along 展开更多
关键词 II Synthesis and Crystal Structure of a three-dimensional Mn coordination Polymer with 3 Pyrazin-2-yloxy pyridine and Azide Anion as Mixed Bridge Ligand
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Three-Dimensional Space Interpolation of Grey / Depth Image Sequence-A New Technique of Computer Graphics Synthesis
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作者 Wang Xincheng, Zhu Weile, Zhu Xiaokun and Gu DerenChengdu University of Electronic Science and Technology, Chengdu 610054 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第3期70-77,共8页
This paper advances a three-dimensional space interpolation method of grey / depth image sequence, which breaks free from the limit of original practical photographing route. Pictures can cruise at will in space. By u... This paper advances a three-dimensional space interpolation method of grey / depth image sequence, which breaks free from the limit of original practical photographing route. Pictures can cruise at will in space. By using space sparse sampling, great memorial capacity can be saved and reproduced scenes can be controlled. To solve time consuming and complex computations in three-dimensional interpolation algorithm, we have studied a fast and practical algorithm of scattered space lattice and that of 'Warp' algorithm with proper depth. By several simple aspects of three dimensional space interpolation, we succeed in developing some simple and practical algorithms. Some results of simulated experiments with computers have shown that the new method is absolutely feasible. 展开更多
关键词 Grey / depth image three-dimensional space interpolation Computer graphics synthesis Algorithms.
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Urban Three-dimensional Expansion and Its Driving Forces——A Case Study of Shanghai,China 被引量:20
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作者 SHI Longyu SHAO Guofan +4 位作者 CUI Shenghui LI Xuanqi LIN Tao YIN Kai ZHAO Jingzhu 《Chinese Geographical Science》 SCIE CSCD 2009年第4期291-298,共8页
Urban expansion is a phenomenon of urban space increase,and an important measuring index of the process of urbanization.Taking Shanghai as an example,the changes of urban average height and built-up area were studied ... Urban expansion is a phenomenon of urban space increase,and an important measuring index of the process of urbanization.Taking Shanghai as an example,the changes of urban average height and built-up area were studied to represent city's vertical and horizontal increases respectively,and statistical methods were used to analyze the driving forces of urban expansion.The research drew following conclusions:1) The urban expansion process of Shanghai from 1985 to 2006 had a clear periodic feature,and could be divided into three stages:vertical expansion in dominance,coordinated vertical and horizontal expansion,and horizontal expansion in dominance.2) The average height and quantity of buildings in core city were significantly bigger than those in suburbs,but the changing speed of the latter was faster.And 3) urbanization process was the major driving force for the city's horizontal expansion,while industrial structure improvement was the key driving factor for the vertical expansion.Those two driving forces were simultaneously affected by city's political factors. 展开更多
关键词 urban expansion three-dimensional space URBANIZATION urban vertical expansion urban horizontal ex-pansion SHANGHAI China
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Terminal sliding mode control for coordinated motion of a space rigid manipulator with external disturbance 被引量:3
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作者 郭益深 陈力 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第5期583-590,共8页
The control problem of coordinated motion of a free-floating space rigid manipulator with external disturbance is discussed. By combining linear momentum conversion and the Lagrangian approach, the full-control dynami... The control problem of coordinated motion of a free-floating space rigid manipulator with external disturbance is discussed. By combining linear momentum conversion and the Lagrangian approach, the full-control dynamic equation and the Jacobian relation of a free-floating space rigid manipulator are established and then inverted to the state equation for control design. Based on the terminal sliding mode control (SMC) technique, a mathematical expression of the terminal sliding surface is proposed. The terminal SMC scheme is then developed for coordinated motion between the base's attitude and the end-effector of the free-floating space manipulator with external disturbance. This proposed control scheme not only guarantees the existence of the sliding phase of the closed-loop system, but also ensures that the output tracking error converges to zero in finite time. In addition, because the initial system state is always at the terminal sliding surface, the control scheme can eliminate reaching phase of the SMC and guarantee global robustness and stability of the closed-loop system. A planar free-floating space rigid manipulator is simulated to verify the feasibility of the proposed control scheme. 展开更多
关键词 free-floating space rigid manipulator external disturbance terminal slidingsurface coordinated motion terminal sliding mode control
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Multiconstraint adaptive three-dimensional guidance law using convex optimization 被引量:6
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作者 FU Shengnan LIU Xiaodong +1 位作者 ZHANG Wenjie XIA Qunli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期791-803,共13页
The traditional guidance law only guarantees the accuracy of attacking a target. However, the look angle and acceleration constraints are indispensable in applications. A new adaptive three-dimensional proportional na... The traditional guidance law only guarantees the accuracy of attacking a target. However, the look angle and acceleration constraints are indispensable in applications. A new adaptive three-dimensional proportional navigation(PN) guidance law is proposed based on convex optimization. Decomposition of the three-dimensional space is carried out to establish threedimensional kinematic engagements. The constraints and the performance index are disposed by using the convex optimization method. PN guidance gains can be obtained by solving the optimization problem. This solution is more rapid and programmatic than the traditional method and provides a foundation for future online guidance methods, which is of great value for engineering applications. 展开更多
关键词 proportional navigation(PN) adaptive guidance law three-dimensional space second-order cone programming(SOCP) convex optimal control
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Three-dimensional tidal current numerical model of the Oujiang Estuary 被引量:2
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作者 LI Mengguo LI Wendan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2009年第3期17-25,共9页
The characteristics of three-dimensional (3-D) tidal current in the Oujiang Estuary are investigated according to in situ observations. The Oujiang Estuary has features of irregular coastline, complex topography, ma... The characteristics of three-dimensional (3-D) tidal current in the Oujiang Estuary are investigated according to in situ observations. The Oujiang Estuary has features of irregular coastline, complex topography, many islands, moveable boundary, and submerged dyke, therefore, σ 3-D numerical model oil an unstructured triangular grid has been degeloped. The σ coordinate transforination, the moveable boundary and submerged dyke treatment techniques were employed in the model so it is suitable for the tidal simulations in the Oujing Estuary with submerged dyke and moveable boundary problems. The model is evaluated with the in situ data, and the results show that the calculated water elevations at 19 stations and currents at 19 profiler stations are in good agreement with measured data both in magnitude and phase. This numerical model is applied to the 3-D tidal circulation simulations of experiments in stopping flow transport through the South Branch of the Oujiang Estuary, and the feasibility to cutoff the flow in the South Branch of the Oujiang Estuary is demonstrated by numerical simulation experiments. The developed numerical model simulated the 3-D tidal current circulations in complicated coastal and estuarine waters very well. 展开更多
关键词 Oujiang Estuary three-dimensional tidal current mathematical model numerical simulation triangular grid σ coordinate transformation
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Obstacle avoidance method of three-dimensional obstacle spherical cap 被引量:3
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作者 YANG Xiuxia ZHANG Yi ZHOU Weiwei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第5期1058-1068,共11页
Focusing on obstacle avoidance in three-dimensional space for unmanned aerial vehicle(UAV), the direct obstacle avoidance method in dynamic space based on three-dimensional velocity obstacle spherical cap is proposed,... Focusing on obstacle avoidance in three-dimensional space for unmanned aerial vehicle(UAV), the direct obstacle avoidance method in dynamic space based on three-dimensional velocity obstacle spherical cap is proposed, which quantifies the influence of threatening obstacles through velocity obstacle spherical cap parameters. In addition, the obstacle avoidance schemes of any point on the critical curve during the multi-obstacles avoidance are given. Through prediction, the insertion point for the obstacle avoidance can be obtained and the flight path can be replanned. Taking the Pythagorean Hodograph(PH) curve trajectory re-planning as an example, the three-dimensional direct obstacle avoidance method in dynamic space is tested. Simulation results show that the proposed method can realize the online obstacle avoidance trajectory re-planning, which increases the flexibility of obstacle avoidance greatly. 展开更多
关键词 three-dimensional direct space obstacle avoidance velocity obstacle cone velocity obstacle spherical cap
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Three-Dimensional Metacomposite Based on Different Ferromagnetic Microwire Spacing for Electromagnetic Shielding 被引量:4
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作者 QIAO Ye JIANG Qian +2 位作者 UDDIN Azim QIN Faxiang WU Liwei 《Journal of Donghua University(English Edition)》 CAS 2022年第3期206-210,共5页
An electromagnetic shielding metacomposite based on the absorbing mechanism was prepared by weaving ferromagnetic microwires into the three-dimensional(3D)fabric.The influence of the ferromagnetic microwire spacing on... An electromagnetic shielding metacomposite based on the absorbing mechanism was prepared by weaving ferromagnetic microwires into the three-dimensional(3D)fabric.The influence of the ferromagnetic microwire spacing on electromagnetic shielding performance and the electromagnetic shielding mechanism of 3D metacomposites were studied.The total electromagnetic shielding performance increases with the increase of electromagnetic wave frequency.3D metacomposites based on the absorbing mechanism can avoid the secondary pollution of electromagnetic waves,and have great potential in military,civil,aerospace and other fields. 展开更多
关键词 three-dimensional(3D)metacomposite ferromagnetic microwire spacing electromagnetic shielding MECHANISM
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Constructing Three-Dimension Space Graph for Outlier Detection Algorithms in Data Mining 被引量:1
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作者 ZHANG Jing 1,2 , SUN Zhi-hui 1 1.Department of Computer Science and Engineering, Southeast University, Nanjing 210096, Jiangsu, China 2.Department of Electricity and Information Engineering, Jiangsu University, Zhenjiang 212001, Jiangsu, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第5期585-589,共5页
Outlier detection has very important applied value in data mining literature. Different outlier detection algorithms based on distinct theories have different definitions and mining processes. The three-dimensional sp... Outlier detection has very important applied value in data mining literature. Different outlier detection algorithms based on distinct theories have different definitions and mining processes. The three-dimensional space graph for constructing applied algorithms and an improved GridOf algorithm were proposed in terms of analyzing the existing outlier detection algorithms from criterion and theory. Key words outlier - detection - three-dimensional space graph - data mining CLC number TP 311. 13 - TP 391 Foundation item: Supported by the National Natural Science Foundation of China (70371015)Biography: ZHANG Jing (1975-), female, Ph. D, lecturer, research direction: data mining and knowledge discovery. 展开更多
关键词 OUTLIER DETECTION three-dimensional space graph data mining
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Coordinated Planning Transmission Tasks in Heterogeneous Space Networks:A Semi-Distributed Approach 被引量:1
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作者 Runzi Liu Weihua Wu +3 位作者 Zhongyuan Zhao Xu Ding Di Zhou Yan Zhang 《China Communications》 SCIE CSCD 2023年第1期261-276,共16页
This paper studies the coordinated planning of transmission tasks in the heterogeneous space networks to enable efficient sharing of ground stations cross satellite systems.Specifically,we first formulate the coordina... This paper studies the coordinated planning of transmission tasks in the heterogeneous space networks to enable efficient sharing of ground stations cross satellite systems.Specifically,we first formulate the coordinated planning problem into a mixed integer liner programming(MILP)problem based on time expanded graph.Then,the problem is transferred and reformulated into a consensus optimization framework which can be solved by satellite systems parallelly.With alternating direction method of multipliers(ADMM),a semi-distributed coordinated transmission task planning algorithm is proposed,in which each satellite system plans its own tasks based on local information and limited communication with the coordination center.Simulation results demonstrate that compared with the centralized and fully-distributed methods,the proposed semi-distributed coordinated method can strike a better balance among task complete rate,complexity,and the amount of information required to be exchanged. 展开更多
关键词 heterogeneous space network transmission task task planning coordinated scheduling
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A Modified T/2 Fractionally Spaced Coordinate Transformation Blind Equalization Algorithm 被引量:3
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作者 Yecai GUO Xueqing ZHAO +1 位作者 Zhenxin LIU Min GAO 《International Journal of Communications, Network and System Sciences》 2010年第2期183-189,共7页
When T/2 Fractionally Spaced blind Equalization Algorithm based Constant Modulus Algorithm (T/2-FSE- CMA) is employed for equalizing higher order Quadrature Amplitude Modulation signals (QAM), it has disadvantages of ... When T/2 Fractionally Spaced blind Equalization Algorithm based Constant Modulus Algorithm (T/2-FSE- CMA) is employed for equalizing higher order Quadrature Amplitude Modulation signals (QAM), it has disadvantages of low convergence speed and large Mean Square Error (MSE). For overcoming these disadvantages, a Modified T/2 Fractionally Spaced blind Equalization algorithm based on Coordinate Transformation and CMA (T/2-FSE-MCTCMA) was proposed by analyzing the character of 16QAM signal constellations. In the proposed algorithm, real and imaginary parts of input signal of T/2 fractionally spaced blind equalizer are equalized, respectively, and output signals of equalizer are transformed to the same unit circle by coordinate transformation method, a new error function is defined after making coordinate transformation and used to adjust weight vector of T/2 fractionally spaced blind equalizer. The proposed algorithm can overcome large misjudgments of T/2 fractionally spaced blind equalization algorithm for equalizing multi-modulus higher order QAM. Simulation results with underwater acoustic channel models demonstrate that the proposed T/2-FSE-MCTCMA algorithm outperforms T/2 Fractionally Spaced blind Equalization algorithm bas-ed on Coordinate Transformation and CMA (T/2-FSE-CTCMA) and the T/2-FSE-CMA in convergence rate and MSE. 展开更多
关键词 BLIND EQUALIZATION UNDERWATER Acoustic Channel coordinate-Transformation Fractionally spaced EQUALIZER
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New coordination scheme for multi-robot systems based on state space models
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作者 Xie Wenlong Su Jianbo Lin Zongli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第4期722-734,共13页
A new coordination scheme for multi-robot systems is proposed. A state space model of the multi- robot system is defined and constructed in which the system's initial and goal states are included along with the task ... A new coordination scheme for multi-robot systems is proposed. A state space model of the multi- robot system is defined and constructed in which the system's initial and goal states are included along with the task definition and the system's internal and external constraints. Task accomplishment is considered a transition of the system state in its state space (SS) under the system's constraints. Therefore, if there exists a connectable path within reachable area of the SS from the initial state to the goal state, the task is realizable. The optimal strategy for the task realization under constraints is investigated and reached by searching for the optimal state transition trajectory of the robot system in the SS. Moreover, if there is no connectable path, which means the task cannot be performed Successfully, the task could be transformed to be realizable by making the initial state and the goal state connectable and finding a path connecting them in the system's SS. This might be done via adjusting the system's configuration and/or task constraints. Experiments of multi-robot formation control with obstacles in the environment are conducted and simulation results show the validity of the proposed method. 展开更多
关键词 multi-robot system coordinATION state space formation maneuver SUBGOAL
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Adaptive neural network control for coordinated motion of a dual-arm space robot system with uncertain parameters
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作者 郭益深 陈力 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第9期1131-1140,共10页
Control of coordinated motion between the base attitude and the arm joints of a free-floating dual-arm space robot with uncertain parameters is discussed. By combining the relation of system linear momentum conversati... Control of coordinated motion between the base attitude and the arm joints of a free-floating dual-arm space robot with uncertain parameters is discussed. By combining the relation of system linear momentum conversation with the Lagrangian approach, the dynamic equation of a robot is established. Based on the above results, the free-floating dual-arm space robot system is modeled with RBF neural networks, the GL matrix and its product operator. With all uncertain inertial system parameters, an adaptive RBF neural network control scheme is developed for coordinated motion between the base attitude and the arm joints. The proposed scheme does not need linear parameterization of the dynamic equation of the system and any accurate prior-knowledge of the actual inertial parameters. Also it does not need to train the neural network offline so that it would present real-time and online applications. A planar free-floating dual-arm space robot is simulated to show feasibility of the proposed scheme. 展开更多
关键词 flee-floating dual-arm space robot RBF neural network GL matrix andits product operator coordinated motion adaptive control
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