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健美操课“多维系统”教学评价模式的构建与实证 被引量:1
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作者 唐阳成 《当代体育科技》 2017年第11期248-248,250,共2页
近年来,随着我国社会的发展以及繁荣,我国的教育事业获得了长足的发展以及改革。在这样的大背景之下,素质教育日渐发展,而体育课程教学也日渐繁荣。目前,我国的教育机构遵循"以学生发展为本"的教育理念,加强对于"多维系... 近年来,随着我国社会的发展以及繁荣,我国的教育事业获得了长足的发展以及改革。在这样的大背景之下,素质教育日渐发展,而体育课程教学也日渐繁荣。目前,我国的教育机构遵循"以学生发展为本"的教育理念,加强对于"多维系统"教学评价模式的构建以及运用。该文基于此,分析探讨健美操课"多维系统"教学评价模式的构建,并就该评价模式的作用进行了分析。 展开更多
关键词 健美操 “多维系统” 教学评价模式 构建与实证
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AVAILABILITY SIMULATION OF MULTI-COMPONENT SYSTEM BASED ON OPPORTUNISTIC MAINTENANCE POLICY 被引量:5
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作者 蔡景 左洪福 吕德峰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第3期219-223,共5页
A multi-component system has the long fixed maintenance time, so the opportunistic maintenance policy is adopted to put preventive replacement and corrective replacement together, so that the long fixed maintenance ti... A multi-component system has the long fixed maintenance time, so the opportunistic maintenance policy is adopted to put preventive replacement and corrective replacement together, so that the long fixed maintenance time can be shared by more than one component, and the system availability can be improved. Then, the generation characteristics of the random failure time are researched based on the replacement maintenance and the minima[ maintenance. Furthermore, by choosing the opportunistic replacement ages of each component as opti- mized variables, a simulation algorithm based on an opportunistic maintenance policy is designed to maximize the total availability. Finally, the simulation result shows the validity of the algorithm by an example. 展开更多
关键词 AVAILABILITY multi-component system ALGORITHMS opportunistic maintenance minimal maintenance
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Perfect Transfer of Many-Particle Quantum State via High-Dimensional Systems with Spectrum-Matched Symmetry 被引量:3
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作者 LI Ying SONG Zhi SUN Chang-Pu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期445-448,共4页
The quantum state transmission through the medium of high-dimensional many-particle system (boson or spinless fermion) is generally studied with a symmetry analysis. We discover that, if the spectrum of a Hamiltonia... The quantum state transmission through the medium of high-dimensional many-particle system (boson or spinless fermion) is generally studied with a symmetry analysis. We discover that, if the spectrum of a Hamiltonian matches the symmetry of a fermion or boson system in a certain fashion, a perfect quantum state transfer can be implemented without any operation on the medium with pre-engineered nearest neighbor (NN). We also study a simple but realistic near half-filled tight-bindlng fermion system wlth uniform NN hopping integral. We show that an arbitrary many-particle state near the fermi surface can be perfectly transferred to its translational counterpart. 展开更多
关键词 high-dimensional many-particle system perfect quantum state transfer
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Investigation of Dynamic Behavior in 1D Non-uniform Granular System 被引量:1
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作者 ZHANG Duan-Ming SU Xiang-Ying YU Bo-Ming LI Rui PAN Gui-Jun SUN Hong-Zhang YIN Yan-Ping SUN Fan HE Min-Hua LIU Dan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3X期551-554,共4页
We present a non-uniform granular system in one-dimensional case, whose granularity distribution has the fractal characteristic. The particles are subject to inelastic mutual collisions and obey Langevin equation betw... We present a non-uniform granular system in one-dimensional case, whose granularity distribution has the fractal characteristic. The particles are subject to inelastic mutual collisions and obey Langevin equation between collisions. By Monte Carlo simulation we study the dynamic actions of the system. Far from the equilibrium, i.e., τ 〉〉 τe, the results of simulation indicate that the inhomogeneity of the system and the inelasticity of the particles have great influences on the dynamic properties of the system, and correspondingly the influence of the inhomogeneity is more significant. 展开更多
关键词 INELASTICITY restitution coefficient e INHOMOGENEITY fractal dimension D non-uniform granular system
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Scattering Phase Correction for Semiclassical Quantization Rules in Multi-Dimensional Quantum Systems 被引量:1
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作者 HUANG Wen-Min MOU Chung-Yu CHANG Cheng-Hung 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第2期250-256,共7页
While the scattering phase for several one-dimensional potentials can be exactly derived, less is known in multi-dimensional quantum systems. This work provides a method to extend the one-dimensional phase knowledge t... While the scattering phase for several one-dimensional potentials can be exactly derived, less is known in multi-dimensional quantum systems. This work provides a method to extend the one-dimensional phase knowledge to multi-dimensional quantization rules. The extension is illustrated in the example of Bogomolny's transfer operator method applied in two quantum wells bounded by step potentials of different heights. This generalized semiclassical method accurately determines the energy spectrum of the systems, which indicates the substantial role of the proposed phase correction. Theoretically, the result can be extended to other semiclassical methods, such as Gutzwiller trace formula, dynamical zeta functions, and semielassical Landauer Buttiker formula. In practice, this recipe enhances the applicability of semiclassical methods to multi-dimensional quantum systems bounded by general soft potentials. 展开更多
关键词 Bogomolny's transfer operator semiclassical quantization rules quantum chaos
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Multilengthtwo-di mensional codesfor optical CDMAsystem
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作者 ZHOU Xiu-li HU Yu 《Optoelectronics Letters》 EI 2005年第3期232-234,共3页
A new class of multilength, constant-weight and two-dimensional multiwavelength optical orthogonal code (2D MWOOCs) with large capacity and good correlation properties is constructed based on multilength one-dimension... A new class of multilength, constant-weight and two-dimensional multiwavelength optical orthogonal code (2D MWOOCs) with large capacity and good correlation properties is constructed based on multilength one-dimensional (1D) OOCs. The performance of these new MWOOCs in an OCDMA network with double-services is analyzed. The result shows that media with the shorter codeword performs much better than the media with longer codeword, and OCDMA system with these new multilength MWOOCs performs well. These features allow multimedia transmission of large capacity in OCDMA system. 展开更多
关键词 二维代码 CDMA 码分多址 通信系统
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Benefiting from providing multi-dimensional view of peers in overlay of P2P streaming system
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作者 苏杭 Wang Jinlin You Jiali 《High Technology Letters》 EI CAS 2013年第2期214-220,共7页
Most overlay of existing P2P streaming systems just focus on the view point of video content data.An multi-dimensional overlay for the P2P streaming system(MDOPS) is proposed for providing multi-dimensional view inclu... Most overlay of existing P2P streaming systems just focus on the view point of video content data.An multi-dimensional overlay for the P2P streaming system(MDOPS) is proposed for providing multi-dimensional view including video data,peers' service capability and online stability based on locality sensitive hashing.MDOPS organizes all Live/VoD peers and the above multi-dimensional information in a one-dimensinal DHT,uses range resource information publish/search and introduces multiple load balancing methods.MDOPS maintains an additional candidate coordinating peer list with high qualified peers who own the video data the peer would possibly access currently and in future.This list could speed up the process of searching peers for data scheduling layer.Simulation experiment based on trace of real streaming system has testified that MDOPS can effectively improve the quality of search results and smooth load distribution among peers without increasing the cost of resource publish/search. 展开更多
关键词 Peer-to-Peer (P'2P) STREAMING OVERLAY locality sensitive hashing rangesearch load balance
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The Indexation and Monitoring of the Modern Transborder Processes
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作者 Serhii Ustych 《Journal of Mathematics and System Science》 2013年第11期592-596,共5页
In the paper are analysed the phenomenon oftransborder processes, are identified the main levels of its vertical structure. In order to adequately reflect the objective reality of modern transfrontier processes, the a... In the paper are analysed the phenomenon oftransborder processes, are identified the main levels of its vertical structure. In order to adequately reflect the objective reality of modern transfrontier processes, the author distinguishes within the multi-layered concept of 'transfrontier' three levels as far as spatial dimensions are concerned: macro, mezzo and micro.The proposed definition of the nature and types of modern cross-border processes has the great theoretical and practical significance. This is evidenced, for example, in the work on quantitative and qualitative assessment oftransborder processes. Presented the basic notions of the developed system on indexation and monitoring of transborder cooperation at the new Eastern border of the European Union. 展开更多
关键词 System methodology transborder cooperation transborder statistics.
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The Effect of Land Use on Soil Organic Carbon Stocks in Lake Victoria Crescent Agro-Ecological Zone, Uganda
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作者 David Akodi Everline Komuttmga +2 位作者 Choice Agaba Kevin John Oratungye Elizabeth Ahumuza 《Journal of Agricultural Science and Technology(A)》 2016年第3期154-160,共7页
The effect of land use on soil organic carbon (SOC) stocks and depth distribution of SOC was investigated in the Lake Victoria Crescent ago-ecological zone of Uganda. Soil samples were collected from six land use ty... The effect of land use on soil organic carbon (SOC) stocks and depth distribution of SOC was investigated in the Lake Victoria Crescent ago-ecological zone of Uganda. Soil samples were collected from six land use types at 0-30, 30-60 and 60-90 cm from profile pits dug in similar soils and slopes. Results indicated that SOC stocks significantly differed across the various land use systems. SOC also varied significantly by depth. The highest SOC and pH were recorded under natural forest-strict nature. Grassland had the lowest SOC but the highest bulk density (BD). Phosphorous (P) was the highest in banana-coffee systems and the lowest under tea plantations. The lowest values of pH and BD were found in highly disturbed natural forest. The upper layers of the soil (0-30 cm) stored higher amounts of SOC compared to other depths (30-60 cm and 60-90 cm). Land use therefore has a significant effect on SOC and other soil physical and chemical properties. 展开更多
关键词 Soil organic carbon land use change land use systems Mabira forest.
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Virtual design and analysis with multi-dimension coupling for engineering machinery cooling system 被引量:3
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作者 CAI HuiKun QIAN YaoYi +3 位作者 HOU Liang WANG WenWu ZHANG EnLai YANG WeiPing 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2015年第1期117-122,共6页
A good cooling circle should ensure that the system can work at an appropriate temperature in the requirements of power increase,engine compartment constraint and working demands for modern engineering machinery,which... A good cooling circle should ensure that the system can work at an appropriate temperature in the requirements of power increase,engine compartment constraint and working demands for modern engineering machinery,which asks for a thorough understanding of system thermal loads before practical production.However,traditional experiment method spends a long time,costs a huge resource but lacks efficiency,whereas virtual design can avoid the shortcomings of traditional method and can analyze operating states adequately with variable loads on engine,generator,drives,battery pack and HVAC systems.Therefore,this paper focuses on a new virtual design method based on multi-dimension coupled simulation adopting Flowmaster software for initial prediction and CFX tool for further optimization.The simulation results in different operating conditions are compared and validated with experiments.Orthogonal experiment and range analysis are used to explore key parameters of cooling system.The research will be helpful in guiding future design and optimization of engineering machinery. 展开更多
关键词 engineering machinery cooling system virtual design multi-dimension coupled simulation radiator air inlet temperature
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Method for extracting geometrical characteristics of joint probability density based on contour lines
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作者 Shengli Chen Zhiqiang Wu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2022年第2期130-140,I0004,共12页
This paper presents a method for extracting geometrical features of the joint probability density function(PDF)of two-dimensional systems based on its contour lines,with particular interests given to the number and po... This paper presents a method for extracting geometrical features of the joint probability density function(PDF)of two-dimensional systems based on its contour lines,with particular interests given to the number and position of peaks and craters.In order to detect those two types of structures,a series of horizontal planes are applied to truncate the joint PDF with contour lines generated.Starting with the analysis of contour lines in a single plane,shape characteristics of the peak and the crater can be reflected on the contour lines in the aspects of gradient direction and inclusion relationship.Aided by the properties of PDF,the information about gradient direction and inclusion relationship of contour lines can be obtained simultaneously if the contour tree is built.According to the contour tree,the contour lines can be classified as two groups.Then the corresponding relation between contour lines in different planes is discussed.Based on the corresponding relation,clustering analysis about contour lines belonging to the same group but having different heights is performed.Two sets of contour lines are finally obtained as the simplest expression of geometrical characteristics of a joint PDF.They can be used to obtain the number and position of each peak and crater.Three oscillators of different types are chosen to test this method,which shows that this method can pave the way for numerical calculation about the stochastic P-bifurcation of multi-dimensional systems. 展开更多
关键词 Joint probability density function PEAK CRATER Contour lines Stochastic P-bifurcation
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Breathers and Rogue Waves Derived from an Extended Multi-dimensional N-Coupled Higher-Order Nonlinear Schrdinger Equation in Optical Communication Systems
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作者 Cheng-Lin Bai Yue-Jin Cai Qing-Long Luo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第9期255-262,共8页
In this paper, an extended multi-dimensional N-coupled higher-order nonlinear Schr¨odinger equation (NCHNLSE), which can describe the propagation of the ultrashort pulses in wavelength division multiplexing (WDM)... In this paper, an extended multi-dimensional N-coupled higher-order nonlinear Schr¨odinger equation (NCHNLSE), which can describe the propagation of the ultrashort pulses in wavelength division multiplexing (WDM)systems, is investigated. By the bilinear method, we construct the breather solutions for the extended (1+1),(2+1) and(3+1)-dimensional N-CHNLSE. The rogue waves are derived as a limiting form of breathers with the aid of symbolic computation. The effect of group velocity dispersion (GVD), third-order dispersion (TOD) and nonlinearity on breathers and rogue waves solutions are discussed in the optical communication systems. 展开更多
关键词 N-coupled higher-order nonlinear SchrSdinger equations MULTI-DIMENSIONAL rogue waves BREATHERS bilinear transformation
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Coupled two-dimensional discrete element and multibody dynamic modeling for interaction of the soil and rough shaped rigid bodies
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作者 Ning Ding Jinyang Liu Caishan Liu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2022年第7期148-163,I0004,共17页
The study of soil and rigid body system interactions is very important for the exploration of the Moon and Mars worldwide.The discrete element method(DEM)is a relatively accurate simulation method to study dry sand so... The study of soil and rigid body system interactions is very important for the exploration of the Moon and Mars worldwide.The discrete element method(DEM)is a relatively accurate simulation method to study dry sand soil mechanical properties.However,it is not suitable for bodies that are in mutual contact,connected due to constraints or have complex inertia properties due to their geometry.An efficient combination of the two-dimensional discrete element and multibody dynamic modeling method is proposed to solve the problem,in which the contacts and frictions among the granular spheres and the multibody system,including the smooth and rough rigid bodies,are taken into account.In this work,the soil field is modeled by a two-dimensional DEM,and the dynamics of the constrained rigid body system are modeled by the Cartesian method.A detection algorithm is developed to address the interactions between spherical discrete elements and roughly shaped rigid bodies.The advantage of this coupled method is that it enables the simultaneous capture of both responses.Finally,the program is verified by simulation experiments of the three-ball collision and the collision among the rectangular bars and the three balls.Based on this,the movement of the toothed wheel in the granular matter is analyzed,and the results show that the wheel with six teeth and 30°inclination has the fastest forward speed.In extraterrestrial objects,the wheel grip worsens,but the forward speed first increases and then decreases with decreasing gravity acceleration and loads on wheels,which proves that the coupled two-dimensional DEM and multibody dynamic program is effective in solving engineering problems. 展开更多
关键词 Discrete element method Multibody dynamic system Rough-shaped rigid body Toothed wheel in granular matter
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