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基于singularity的超算资源容器化

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信息技术与信息化 2024年第6期 120-126页

作者：王祥凯山东正云信息科技有限公司山东济南250098

深度学习往往伴随着大量的计算,属于典型的高性能计算(HPC)应用。基于Python的深度学习中往往使用PyTorch或者TensorFlow库,环境的配置与管理极为复杂,可重复性低,导致代码的升级、管理、测试、迁移成为大难题。为此,诞生了容器化技术... 详细信息

深度学习往往伴随着大量的计算,属于典型的高性能计算(HPC)应用。基于Python的深度学习中往往使用PyTorch或者TensorFlow库,环境的配置与管理极为复杂,可重复性低,导致代码的升级、管理、测试、迁移成为大难题。为此,诞生了容器化技术。容器化技术以Docker为代表,通过在迁移代码的同时迁移代码运行环境,从而避免了代码在移植的时候存在繁杂的环境配置过程。但是超算服务器与普通的服务器又有很大的差别,如开发人员无root权限,测试代码时需要进行资源管理(内存,CPU)。这些问题都让Docker技术在HPC环境的应用受限,针对以上问题,使用singularity代替Docker,在神威蓝光II型超级计算机上尝试生成了Python3.7+Numpy+Pandas+Scipy数据科学计算环境的singularity镜像文件,在阿里云服务器上无root权限创建容器并成功运行了距离判别Python计算程序。结果表明,使用singularity可以解决Docker在服务器上面的root权限问题,有助于深度学习环境在不同HPC服务器上面的部署。

关键词：容器化技术高性能计算(HPC) Docker singularity

singularity problem of control moment gyro cluster with vibration isolators

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Chinese Journal of Aeronautics 2016年第1期29卷 238-247页

作者： Cui Yinghui Zheng Gangtie School of Aerospace Tsinghua University

As powerful torque amplification actuators, control moment gyros （CMGs） are often used in the attitude control of many state-of-the-art high resolution satellites. However, the distur- bance generated by the CMGs can not only reduce the attitude stability of a satellite but also dete- riorate the performance of optic payloads. Currently, CMG vibration isolators are widely used to target this problem. The isolators can affect the singularity of the CMG system as they are placed between the CMGs and the satellite bus and provide additional freedoms to the CMG system due to their flexibility. The formulation of the output torque of a CMG is studied first considering the dynamic imbalance of its spin rotor and then the deformation angle as a result of the isolator＇s flex- ibility is calculated. With the additional freedoms, the influence of isolator on the singularity problem is studied and a new steering logic to escape from the singular states is proposed.

关键词： Satellite singularity Steering logic Torque error Vibration isolation

singularity Analysis of a 3-RPS Parallel Manipulator Using Geometric Algebra

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Chinese Journal of Mechanical Engineering 2015年第6期28卷 1204-1212页

作者： LI Qinchuan XIANG Ji'nan CHAI Xinxue WU Chuanyu Mechatronic Institute Zhejiang Sci-Tech University

Singular configurations must be avoided in path planning and control of a parallel manipulator. However, most studies rarely focus on an overall singularity loci distribution of lower-mobility parallel mechanisms. Geometric algebra is employed in analysis of singularity of a 3-RPS parallel manipulator. Twist and wrench in screw theory are represented in geometric algebra. Linear dependency of twists and wrenches are described by outer product in geometric algebra. Reciprocity between twists and constraint wrenches are reflected by duality. To compute the positions of the three spherical joints of the 3-RPS parallel manipulator, Tilt-and-Torsion angles are used to describe the orientation of the moving platform. The outer product of twists and constraint wrenches is used as an index for closeness to singularity（ICS） of the 3-RPS parallel manipulator. An overall and thorough perspective of the singularity loci distribution of the 3-RPS parallel manipulator is disclosed, which is helpful to design, trajectory planning and control of this kind of parallel manipulator.

关键词： singularity parallel manipulator geometric algebra

singularity Analsis of Geometric Constraint Systems

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Journal of Computer Science & Technology 2002年第3期17卷 314-323页

作者：彭小波 NationalCADSupportSoftwareEngineeringResearchCenterHauzhongUniversityofScienceandTechnology Wuhan4300

singularity analysis in an important subject of the geometric constraint satisfaction *** this paper,three kinds of singularities are described and corresponding identifcation methods are presented for both under0constrained systems and over-constrained systems,Another special but common singularity for under-constrained geometric systems,pseudo-singularity,is ***-singularity is caused by a variety of constraint mathching of under-constrained systems and can be removed by improving constraint *** avoid pseudo-singularity and decide redundant constraints adaptively,a differentiaiton algorithm is proposed in the *** corrctness and effciency have been validated through its practical applications in a 2D/3D geometric constraint solver CBA.

关键词： geometric constraint satisfaction parametric design singularity redundant constraint pseudo-singularity

singularity analysis of Jeffcott rotor-magnetic bearing with time delays

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Applied Mathematics(A Journal of Chinese Universities) 2012年第4期27卷 419-427页

作者： XU Xiu-yan JIANG Wei-hua Department of Mathematics Heilongjiang Institute of Science and TechnologyHarbin 150027China Department of Mathematics Harbin Institute of TechnologyHarbin 150001China

A Jeffcott rotor-magnetic bearing with time delays is investigated in this paper. Firstly, it is found that the characteristic equation of the system satisfies the conditions of the singularity. Secondly, the center manifold reduction and normal form are employed to study the bifurcation from simple zero and zero-purely imaginary singularities. The results of this paper will help to understand the influence of the time delays in feedback loop on the dynamics of rotor-magnetic bearing system.

关键词： Jeffcott rotor-magnetic bearing time delay singularity normal form.

singularity-free Green's function for EM sources embedded in a stratified medium

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Applied Geophysics 2016年第1期13卷 25-36,217,218页

作者：翁爱华刘云鹤殷长春贾定宇吉林大学地球探测科学与技术学院长春130026 中国地质科学院地球物理地球化学勘查研究院廊坊065000

We present a method to unify the calculation of Green＇s functions for an electromagnetic（EM） transmitting source embedded in a homogeneous stratified medium.A virtual interface parallel to layer interfaces is introduced through the source *** potentials for Green＇s function are derived by decomposing the partial wave solutions to Helmholtz＇s equations into upward and downward within *** amplitudes of the potentials in each stratum are obtained recursively from the initial amplitudes at the source *** initial amplitudes are derived by coupling with the transmitting sources and following the discontinuity of the tangential electric and magnetic fields at the source *** the initial terms are related to the transmitting sources and thus need to be modified for different transmitters,whereas the kernel connected with the stratified media stays ***,the present method can be easily applied to EM transmitting sources with little *** application of the proposed method to the marine controlled-source electromagnetic method（MCSEM） demonstrates its simplicity and flexibility.

关键词： EM Marine EM Green's function stratified medium singularity

singularity of Some Software Reliability Models and Parameter Estimation Method

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Wuhan University Journal of Natural Sciences 2000年第1期5卷 35-40页

作者： XU Ren-zuo ZHOU Rui YANG Xiao-qing (State Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072, China) Wuhan Univ Wuhan China

According to the principle, “The failure data is the basis of software reliability analysis”, we built a software reliability expert system (SRES) by adopting the artificial intelligence technology. By reasoning out the conclusion from the fitting results of failure data of a software project, the SRES can recommend users “the most suitable model” as a software reliability measurement model. We believe that the SRES can overcome the inconsistency in applications of software reliability models well. We report investigation results of singularity and parameter estimation methods of experimental models in SRES.

关键词： software reliability measurement models software reliability expert system singularity parameter estimation method path following method maximum likelihood ML-fitting algorithm

singularity Detecting with the SecondGeneration Wavelet

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Wuhan University Journal of Natural Sciences 2004年第6期9卷 871-874页

作者： XU Bing-lian 1,2 , YI Xu-ming 1 1.School of Mathematics and Statistics, Wuhan University, Wuhan 430072, Hubei, China 2.College of Science,Nanjing Agriculture University,Nanjing 210095,Jingsu,China School of Mathematics and Statistics Wuhan University Wuhan Hubei China College of Science Nanjing Agriculture University Nanjing Jingsu China

Adopting the lifting scheme, introduced by Sweldens, a new wavelet is constructed. It overcomes the shortcoming of the classical wavelets that has no flexibility in the number of vanishing moment. Two examples are given to prove the second-generation wavelets's potentialities in the singularity detection of signal: a wavelet with vanishing moment and symmetry can be constructed according to the problem. Key words biorthogonal wavelet - lifting scheme - secondgeneration wavelets - singularity CLC number O 174.2 Foundation item: Supported by the National Natural Science Foundation of China (19602014)Biography: XU Bing-lian (1977-), female, Master candidate, research direction: the wavelets application.

关键词： biorthogonal wavelet lifting scheme secondgeneration wavelets singularity

On approach for obtaining approximate solution to highly nonlinear oscillatory system with singularity

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Acta Mechanica Sinica 2020年第4期36卷 910-917页

作者： Zvonko Rakaric Boris Stojic Department of Mechanics Faculty of Technical SciencesUniversity of Novi Sad21000 Novi SadSerbia Department of Mechanization and Design Engineering Faculty of Technical SciencesUniversity of Novi Sad21000 Novi SadSerbia

This paper deals with further investigations of recently introduced so-called low-frequency pendulum mechanism,which represents an extended form of classical *** equation of motion,which is in Eksergian’s form,is a singular and highly nonlinear second order differential *** is transformed by suitable choice of a new “coordinates”into classical form of nonlinear conservative oscillator containing only inertial and restoring force ***,due to the singularity of coefficient of governing equation that shows hyperbolic growth,Laurent series expansion was *** these,we derived a nonsingular nonlinear differential equation,for which there exists an exact solution in the form of a Jacobi elliptic *** using this exact solution,and after returning to the original coordinate,both explicit expression for approximate natural period and solution of motion of mechanism were *** between approximate solution and solution is obtained by numerical integration of exact equation shows noticeable *** of impact of mechanism parameters on period is given.

关键词： Pendulum mechanism Low frequency singularity Laurent series Jacobi elliptic function