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An Efficient Model of Tethers for Tethered Satellite Systems

Advances in Astronautics Science and Technology 2018年第2期1卷 153-160页

作者： Shuguang, Ma Tianshu, Wang School of Aerospace Engineering Tsinghua University Room N911 Mengminwei Technology Building Haidian District Beijing 100084 China

This paper concerns about modeling of tethered satellites systems (TSS). In this paper, tethers of TSS are modeled as chains of elastic rods connected by rigid joints. A group of spatial vectors are used to describe displacement, orientation and deformation of the rods, which can avoid the coupling of trigonometric functions of Euler angles. The coordinates of spatial vectors are chosen as the generalized coordinates of system. Equations of motion are derived and written in explicit form. A computationally efficient algorithm is developed to solve equations of motion. Computational complexity of the developed algorithm is reduced to O(n) (n denotes the number of rods). A numerical experiment is performed. Results about energy show energy conservation principle is obeyed. The same numerical experiment is also performed utilizing multibody software ADAMS. Validity of the presented algorithm is demonstrated by comparing numerical results of the two methods. © 2019, Chinese Society of Astronautics.

关键词： Model of tether Multibody dynamics recursive algorithm Tethered satellites systems

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recursive optimal linear attitude estimator based on star sensor and gyro

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Aerospace Systems 2021年第2期4卷 91-99页

作者： Xu, Guangtan Gong, Deren Duan, Dengping School of Aeronautics and Astronautics Shanghai Jiaotong University Shanghai 200240 China

The optimal linear attitude estimation algorithm takes Rodrigues parameters as the attitude description, which has advantages of small computation volume and high accuracy. Based on the optimal linear attitude estimation algorithm, this article proposes a recursive optimal linear attitude estimator based on star sensor and gyro, introducing historical data and gyro data for auxiliary attitude determination. The fading memory factor is introduced to balance historical and current measurement data. Numerical simulation results show that the proposed algorithm has a higher accuracy than that of Quaternion Estimator (QUEST) and single frame method Linear Attitude Estimation (LAE). The analysis at different angular velocities shows that the algorithm has a wide range of adaptation to angular velocities and can be widely used in engineering tasks. © 2021, Shanghai Jiao Tong University.

关键词： Combined satellite attitude determination Linear attitude determination Memory fading factor recursive algorithm

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High performance Cholesky factorization via blocking and recursion that uses minimal storage 5th

High performance Cholesky factorization via blocking and rec...

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5th International Workshop on Applied Parallel Computing (PARA 2000)

作者： Gustavson, F Jonsson, I IBM Corp Thomas J Watson Res Ctr Yorktown Hts NY 10598 USA Umea Univ Dept Comp Sci SE-90187 Umea Sweden

ISBN: (纸本)354041729X

We present a high performance Cholesky factorization algorithm, called BPC for Blocked Packed Cholesky, which performs better or equivalent to the LAPACK DPOTRF subroutine, but with about the same memory requirements as the LAPACK DPPTRF subroutine, which runs at level 2 BLAS speed. algorithm BPC only calls DGEMM and level 3 kernel routines. It combines a recursive algorithm with blocking and a recursive packed data format. A full analysis of overcoming the non-linear addressing overhead imposed by recursion is given and discussed. Finally, since BPC uses GEMM to a great extent, we easily get a considerable amount of SMP parallelism from an SMP GEMM.

关键词： Cholesky factorization recursive algorithm recursive data structure packed format level 3 BLAS parallelism

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Structure Optimization of Nonrepairable Phased Mission Systems

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IEEE TRANSACTIONS ON SYSTEMS MAN CYBERNETICS-SYSTEMS 2014年第1期44卷 121-129页

作者： Dai, Yuanshun Levitin, Gregory Xing, Liudong Univ Elect Sci & Technol China Collaborat Auton Comp Lab Sch Comp Sci & Engn Chengdu 610054 Peoples R China Univ Massachusetts Dept Elect & Comp Engn Dartmouth MA 02747 USA

System structure optimization is a well-studied problem in the field of reliability engineering, which aims to achieve the best possible reliability versus cost solutions for the system design. This problem is usually solved for systems that do not change their task and configuration during the mission. However, many practical systems are phased-mission systems (PMS), where the mission involves multiple, consecutive, and nonoverlapping phases of operation. An accurate analysis of PMS must consider the dynamics in system configuration, success criteria, and element behavior as well as statistical dependence of element states across phases. In this paper, we propose a method for solving the structure optimization problem of multistate PMS consisting of nonidentical nonrepairable binary elements. The system configuration and demand as well as the failure distributions of system elements can change from phase to phase. The proposed approach is based on a recursive algorithm for the reliability evaluation of PMS and a genetic algorithm for the structure optimization of PMS. The method is illustrated using an example of a six-phased mission running on an airborne distributed computing system.

关键词： Phased-mission system (PMS) recursive algorithm reliability structure optimization

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Image mosaicing using sequential bundle adjustment

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IMAGE AND VISION COMPUTING 2002年第9-10期20卷 751-759页

作者： McLauchlan, PF Jaenicke, A Univ Surrey Sch EE IT & Math Guildford GU2 7XH Surrey England

We describe the construction of accurate panoramic mosaics from multiple images taken with a rotating camera, or alternatively of a planar scene. The novelty of the approach lies in (i) the transfer of photogrammetric bundle adjustment techniques to mosaicing;(ii) a new representation of image line measurements enabling the use of lines in camera self-calibration, including computation of the radial and other non-linear distortion;and (iii) the application of the variable state dimension filter to obtain efficient sequential updates of the mosaic as each image is added. We demonstrate that our method achieves better results than the alternative approach of optimising over pairs of images. (C) 2002 Elsevier Science B.V. All rights reserved.

关键词： bundle adjustment mosaic sequential algorithm recursive algorithm

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New recursuve algorithm on model orders and its application

New recursuve algorithm on model orders and its application

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4th World Congress on Intelligent Control and Automation

作者： Fu, GJ Mu, HW Liu, SQ Tao, GB Wang, JY Daqing Petr Inst Dept Automat & Control Engn Anda 151400 Heilongjiang Peoples R China

In this paper,a new multi-dimentional recursive algorithm is given for multi-input, multi-output ARMAX systems. Satisfactory results can all be obtained in many simulation experiments.

ISBN: (纸本)0780372689

In this paper,a new multi-dimentional recursive algorithm is given for multi-input, multi-output ARMAX systems. Satisfactory results can all be obtained in many simulation experiments.

关键词： identification parameter estimation recursive algorithm modeling

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Design and implementation of chess roles guess probability in military chess computer game 27

Design and implementation of chess roles guess probability i...

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27th Chinese Control and Decision Conference (CCDC)

作者： Wu, Jiehong Lv, Feng Can, Yuqi Zhao, Ziheng Shenyang Aerosp Univ Sch Comp Shenyang 110136 Peoples R China

ISBN: (纸本)9781479970162

In recent years, along with the further study in incomplete information chess-military chess. How to express and address the incomplete information during the process of game, deciding certain moves strategies to obtain higher winning rate increasingly become a new issue. An approach using digit to express incomplete information in military chess is proposed in this paper, a model based on guessing probability to address incomplete information in military chess game is designed, and the programming process is provided. In the National Computer Games Tournament, the game program using this model is stronger than the others. Results are shown as 6 wins, 1 draw, and 1 lost. The average time of each moving step is shorter than opponent 2 second.

关键词： Probability Weight Chess game recursive algorithm

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Reconstruction of cortical sources activities for online classification of electroencephalographic signals.

Reconstruction of cortical sources activities for online cla...

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32nd Annual International Conference of the IEEE Engineering-in-Medicine-and-Biology-Society (EMBC 10)

作者： Fruitet, Joan Clerc, Maureen INRIA Athena Project Team F-06902 Sophia Antipolis France

ISBN: (纸本)9781424441242

We compare the results given by different methods to reconstruct cortical sources activity in order to classify EEG in real time. Two motor imagery experiments were performed. The aim was to retrieve from 1 windows of signal which motor imagery task the subjects were performing. The use of cortical activity reconstruction was compared to Laplacian filtering, which is often used in BCI. A recursive algorithm using Student's t-test was used to select relevant cortical sources. The Beamformer method led to an improvement of the classification for the first experiment, which included six motor imagery tasks. The weighted Minimum-Norm method required the use of a specific head model, extracted from the subject's MRI, to improve the classification. It then gave the best results on the second experiment, achieving a classification rate of 77% compared to 71% for direct use of electrode data and 75% for Laplacian filtering and Beamformer.

关键词： EEG Laplacian filtering MRI array signal processing beamformer biomechanics cortical source activities electrode electroencephalography electroencephalography feature extraction feature extraction filtering theory head model medical signal processing motor imagery task neurophysiology online signal classification recursive algorithm signal classification signal reconstruction signal reconstruction student t-test weighted minimum-norm method

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High Performance recursive Matrix Inversion for Multicore Architectures 15

High Performance Recursive Matrix Inversion for Multicore Ar...

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15th International Conference on High Performance Computing & Simulation (HPCS)

作者： Mahfoudhi, Ryma Achour, Sami Hamdi-Larbi, Olfa Mahjoub, Zaher Univ Tunis El Manar Fac Sci Tunis UR13ES38 Algorithm Parallele & Optimisat Tunis 2092 Tunisia

ISBN: (纸本)9781538632505

There are several approaches for computing the inverse of a dense square matrix, say A, namely Gaussian elimination, block wise inversion, and LU factorization (LUF). The latter is used in mathematical software libraries such as SCALAPACK, PBLAS and MATLAB. The inversion routine in SCALAPACK library (called PDGETRI) consists, once the two factors L and U are known (where A=LU), in first inverting U (PDGETRF) then solving a triangular matrix system giving A(-1). A symmetric way consists in first inverting L, then solving a matrix system giving A(-1). Alternatively, one could compute the inverses of both U and L, then their product and get A(-1). On the other hand, the Strassen fast matrix inversion algorithm is known as an efficient alternative for solving our problem. We propose in this paper a series of different versions for parallel dense matrix inversion based on the 'Divide and Conquer' paradigm. A theoretical performance study permits to establish an accurate comparison between the designed algorithms. We achieved a series of experiments that permit to validate the contribution and lead to efficient performances obtained for large matrix sizes i.e. up to 40% faster than SCALAPACK.

关键词： Divide and Conquer LU factorization Matrix inversion Multicore architecture PBlas recursive algorithm Strassen algorithm

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Two Methods for Constructing Independent Spanning Trees in Alternating Group Networks 20

Two Methods for Constructing Independent Spanning Trees in A...

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20th IEEE International Conference on Software Quality, Reliability, and Security (QRS)

作者： Huang, Jie-Fu Hsieh, Sun-Yuan Natl Cheng Kung Univ Dept Comp Sci & Informat Engn Tainan Taiwan

ISBN: (纸本)9781728189154

In this paper, we propose a recursive and a parallel algorithms, respectively, for constructing independent spanning trees in alternating group networks. The recursive algorithm is BFS-based, while the parallel algorithm is BFS-based and rule-based. Both algorithms are accurate, and furthermore, the parallel algorithm is more efficient than the recursive one.

关键词： Independent spanning trees Alternating group networks recursive algorithm Parallel algorithm Triangle breadth-first search

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