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试析大学生非正式体育群体的形式与特征 被引量:2
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作者 廖民玲 《广西大学学报(哲学社会科学版)》 2008年第z1期293-294,共2页
"以人为本"已成为我国高校体育发展的核心理念,课外体育活动同样也将受到这一发展观的引领。针对高校大学生课外体育锻炼过程中非正式体育群体的表现形式与特征进行了理论分析和研究。结果表明:非正式体育群体主要表现为竞技... "以人为本"已成为我国高校体育发展的核心理念,课外体育活动同样也将受到这一发展观的引领。针对高校大学生课外体育锻炼过程中非正式体育群体的表现形式与特征进行了理论分析和研究。结果表明:非正式体育群体主要表现为竞技型、健身型、娱乐型和社交型四种形式,并呈现出自发性、内部活动一致性以及动态性等特征。 展开更多
关键词 健康第一 非正式体育群体 形式
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Logical-Structure Modeling for Conceptual Design
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作者 孙正兴 张福炎 《Journal of Southeast University(English Edition)》 EI CAS 2001年第1期59-65,共7页
Based on the definition of a logic structure feature to relate logically functional requirements to geometric representation independent upon detailed geometric representation, this paper presents an idea of logical s... Based on the definition of a logic structure feature to relate logically functional requirements to geometric representation independent upon detailed geometric representation, this paper presents an idea of logical structure modeling for computer aided conceptual design and makes attempt to establish a representation formalism of logic structure modeling. The definition and representation of logical structure feature are given and an assembly module definition for supporting top down conceptual design is also proposed. The proposed scheme contributes to several aspects of conceptual design research, especially to provide elementarily a formal methodology for computer aided conceptual design system development and operation. 展开更多
关键词 conceptual design function form transformation logic structure feature representation formalism
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A FORMAL REPRESENTATION FOR FEATURE-BASED DESIGN 被引量:1
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作者 孙正兴 丁秋林 张福炎 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1997年第1期37-46,共10页
Feature based design has been regarded as a promising approach for CAD/CAM integration.This paper aims to establish a domain independent representation formalism for feature based design in three aspects: formal re... Feature based design has been regarded as a promising approach for CAD/CAM integration.This paper aims to establish a domain independent representation formalism for feature based design in three aspects: formal representation,design process model and design algorithm.The implementing scheme and formal description of feature taxonomy,feature operator,feature model validation and feature transformation are given in the paper.The feature based design process model suited for either sequencial or concurrent engineering is proposed and its application to product structural design and process plan design is presented. Some general design algorithms for developing feature based design system are also addressed.The proposed scheme provides a formal methodology elementary for feature based design system development and operation in a structural way. 展开更多
关键词 CAD CAM product modelling design process feature based design representation formalism
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A Definition Formalism of Machining Features for DFM
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作者 孙正兴 张福炎 《Journal of Southeast University(English Edition)》 EI CAS 1999年第1期49-54,共6页
Benefiting from advances in feature technology for design and manufacture can not be expected before a formal methodology is established. This paper makes attempt to establish a definition formalism of machining featu... Benefiting from advances in feature technology for design and manufacture can not be expected before a formal methodology is established. This paper makes attempt to establish a definition formalism of machining features in design for manufacturability from two aspects: formal definition and manufacturability analysis. Some definitions for machining feature based upon the selection and sequencing of material removal operations for component in accordance with the design geometry are presented and a framework of feature based design for manufacturability is outlined correspondingly. The proposed scheme contributes to several aspects of feature based CAD/CAM integration, especially to encourage potentially a more generic approach to the automation of design. 展开更多
关键词 design for manufacturability(DFM) feature technology machining feature definition formalism process planning
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分合之间的误区——关于两个乘法分配律典型错误的简单分析
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作者 邬旭亮 《新教师》 2012年第Z1期118-118,共1页
一、"丢三拉四"错误型我们不妨来听听学生的想法。师:为什么会把89落了?生1:这道题和我们以前做的乘法分配律不一样,我不会做,凭感觉做的。
关键词 乘法分配律 丢三拉四 错误型 解题思路 浙江省奉化市 莼湖镇 分配率 四则混合运算 辅助练习 形式特
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Comparative Study of Rice Morphogenesis with Different Cultivation Methods
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作者 严定春 《Agricultural Science & Technology》 CAS 2012年第11期2424-2428,共5页
[Objective] The aim of this study was to compare the morphological char- acteristics of rice (Oryza sativa L.) with different cultivation methods and investigate the dynamics of organ growth and development characte... [Objective] The aim of this study was to compare the morphological char- acteristics of rice (Oryza sativa L.) with different cultivation methods and investigate the dynamics of organ growth and development characteristics of different rice culti- vars. [Method] Based on continuous field observation and destructive sampling over a growing season, detailed organ morphological data were obtained including leaf length, node number, plant height, tiller number, leaf angle, leaf area and specific leaf weight, to compare organ morphological differences among 4 rice cultivars of Baidao (indica), Jinnanfeng (japonica), 9325 (japonica) and 9915 (japonica) with 3 cultivation methods of field planting in Weigang, pot planting in Weigang, and field planting in Jiangpu. [Result] Maximum leaf length of each node gradually increased at the early growth stage and decreased at the later growth stage, the relationship between maximum leaf length and node position can be described by the equations y=a,,-~ and y=ax+b; node number, growth duration, leaf length and plant height of pot planting rice in Weigang were smaller than that of the other two field planting meth- ods; the relationship between plant height and sunshine duration, plant height and GDD (growing degree days) can be described by the equation y=ax+b, 19.23 ℃.d of GDD (≥10 ≥-d) and 8.12 h of sunshine duration were required to increase 1 cm of plant height; plant height, tiller number, and leaf area of Baidao were higher than that of the other 3 laponica rice cultivars, but the specific leaf weight and leaf angle were smaller. [Conclusion] Comparison of morphological characteristic differ- ences among rice cultivars is an important way to select water-saving and drought- tolerant rice varieties. In this study, the experimental results can be integrated into a rice functional-architectural model to simulate rice organ growth dynamics in a three- dimensional space, thereby providing reference for selecting water-saving and drought-tolerant rice cultivars. 展开更多
关键词 RICE LEAF Plant height Tiller number Leaf angle
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Special Properties of Formal Triangular Matrix Rings 被引量:4
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作者 FAN Wei-li WANG Hui 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期625-632,共8页
We consider the sufficient and necessary conditions for the formal triangular matrix ring being right minsymmetric, right DS, semicommutative, respectively.
关键词 formal triangular matrix ring right minsymmetric ring DS ring semicommutative ring
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The training process: Planning for strength-power training in track and field. Part 1: Theoretical aspects 被引量:3
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作者 Brad H. DeWeese Guy Hornsby +1 位作者 Meg Stone Michael H. Stone 《Journal of Sport and Health Science》 SCIE 2015年第4期308-317,共10页
The process of strength-power training and the subsequent adaptation is a multi-factorial process. These factors range from the genetics and morphological characteristics of the athlete to how a coach selects, orders,... The process of strength-power training and the subsequent adaptation is a multi-factorial process. These factors range from the genetics and morphological characteristics of the athlete to how a coach selects, orders, and doses exercises and loading patterns. Consequently, adaptation from these training factors may largely relate to the mode of delivery, in other words, programming tactics. There is strong evidence that the manner and phases in which training is presented to the athlete can make a profound difference in performance outcome. This discussion deals primarily with block periodization concepts and associated methods of programming for strength-power training within track and field. 2015 Production and hosting by Elsevier B.V. on behalf of Shanghai University of Sport. 展开更多
关键词 Periodization Strength-power training Track and field Training process
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县域金融精准扶贫后期持续性发展的思考与建议——基于基层银行视角
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作者 姚新 《区域金融研究》 2020年第4期63-66,共4页
自中共中央、国务院2015年11月出台《关于打赢脱贫攻坚战的决定》以来,全国金融系统通过发放扶贫小额信贷等金融精准扶贫贷款,实现了金融服务与扶贫的有机结合。截至2019年末,中国已经成为世界上减贫人口最多的国家。但是,另一方面,基... 自中共中央、国务院2015年11月出台《关于打赢脱贫攻坚战的决定》以来,全国金融系统通过发放扶贫小额信贷等金融精准扶贫贷款,实现了金融服务与扶贫的有机结合。截至2019年末,中国已经成为世界上减贫人口最多的国家。但是,另一方面,基层普遍呼吁要迅速研究解决下一步金融精准扶贫成果巩固问题。鉴于此,本文基于基层银行的视角,结合我国四个金融精准扶贫典型示范区实践经验,就县域金融精准扶贫后期可持续发展进行初步探讨,并提出工作建议。 展开更多
关键词 金融精准扶贫 普惠金融 风险分担缓释 合伙发展 形式
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Ashkin-Teller Formalism for Elastic Response of DNA Molecule to External Force and Torque
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作者 CHANG Zhe WANG Ping ZHENG Ying-Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第2期525-528,共4页
We propose an Ashkin-Teller-like model for elastic response of DNA molecule to external force and torque. The base-stacking interaction is described in a simple and uniform way. We obtain the phase diagram of dsDNA, a... We propose an Ashkin-Teller-like model for elastic response of DNA molecule to external force and torque. The base-stacking interaction is described in a simple and uniform way. We obtain the phase diagram of dsDNA, and in particular, the transition from 13 form to the S state induced by stretching and twisting. The elastic response of the ssDNA is presented also in a unified formalism. The close relation of dsDNA molecule structure with elastic response is shown clearly. The calculated folding angle of the dsDNA molecule is 59.2°. 展开更多
关键词 DSDNA elastic property
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Wear Debris Identification Using Feature Extraction and Neural Network
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作者 王伟华 马艳艳 +1 位作者 殷勇辉 王成焘 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期42-45,共4页
A method and results of identification of wear debris using their morphological features are presented. The color images of wear debris were used as initial data. Each particle was characterized by a set of numerical ... A method and results of identification of wear debris using their morphological features are presented. The color images of wear debris were used as initial data. Each particle was characterized by a set of numerical parameters combined by its shape, color and surface texture features through a computer vision system. Those features were used as input vector of artificial neural network for wear debris identification. A radius basis function (RBF) network based model suitable for wear debris recognition was established, and its algorithm was presented in detail. Compared with traditional recognition methods, the RBF network model is faster in convergence, and higher in accuracy. 展开更多
关键词 wear debris CHARACTERIZATION neural network pattern recognition.
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Animation art forms and aesthetic characteristics
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作者 Guolong Zhang 《International Journal of Technology Management》 2013年第7期73-75,共3页
In a very shocking symbol, animation art leads us to the continuing social and philosophical problems. With its unique hypothetical language as the human spirit and emotional material carrier, animation art passes var... In a very shocking symbol, animation art leads us to the continuing social and philosophical problems. With its unique hypothetical language as the human spirit and emotional material carrier, animation art passes various social messages to people. The value of animation art lies in the certain form of expression to convey characteristics of the content and spirit, which is the core issues that Chinese animation industry worthy of attention and research. Animation art as a cultural transmission symbols, bears culture spreading. The combination of cultural heritage and the new animation language means is an important way for animation art to direct towards the life of road. At the same time, let the excellent national culture and art forms combine with modem advanced technology and make innovation and creativity. Only in this way can China's animation talent with a new, unique appearance presented to the audience and occupy an important seat in the world animation art. 展开更多
关键词 animation art aesthetic characteristics manifestations.
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Analysis of generation factors for tectonic deformation in the Xigeda formation in southwestern China 被引量:1
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作者 Li Ping Liu Xingsong +1 位作者 Yang Mei'e Yuan Jingli 《Engineering Sciences》 2012年第1期8-13,共6页
The Xigeda formation is a set of interbreds comprised of halfconsolidated silt,fine sand and clay with clear lamination and total thickness of 300 m.It is dated to be the early Pleistocene and widespread distributed o... The Xigeda formation is a set of interbreds comprised of halfconsolidated silt,fine sand and clay with clear lamination and total thickness of 300 m.It is dated to be the early Pleistocene and widespread distributed on the Quaternary planes of denudation and leveling.This formation has particular tectonic deformation as expressed by deformed belts confined to certain locations,which extend linearly over long distances.It also manifests itself as graben and horst sequences where fault planes are very straight.Various deformation styles,such as horizontal,vertical and oblique dislocations,normal,reverse and thrust faulting resulted in tilts of small blocks in different directions.The clay beds are intruded by underlying sand layers.Parallel ridges and depressions characterize the landscape.These phenomena of deformation are probably the result of intensive vibration of soil bodies during major earthquakes which caused instantaneous shear,compression and extension.The analysis of generation factors for such tectonic deformation provides a new approach for determination of areas with seismic risks,assessment of earthquake intensity and research of earthquake mechanisms. 展开更多
关键词 EARTHQUAKE tectonic deformation Xigeda formation
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An estimation model for the fragmentation properties of brittle rock block due to the impacts against an obstruction 被引量:3
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作者 HOU Tian-xing XU Qiang +2 位作者 XIE Hong-qiang XU Nu-wen ZHOU Jia-wen 《Journal of Mountain Science》 SCIE CSCD 2017年第6期1161-1173,共13页
Mountain hazards with large masses of rock blocks in motion – such as rock falls, avalanches and landslides – threaten human lives and structures. Dynamic fragmentation is a common phenomenon during the movement pro... Mountain hazards with large masses of rock blocks in motion – such as rock falls, avalanches and landslides – threaten human lives and structures. Dynamic fragmentation is a common phenomenon during the movement process of rock blocks in rock avalanche, due to the high velocity and impacts against obstructions. In view of the energy consumption theory for brittle rock fragmentation proposed by Bond, which relates energy to size reduction, a theoretical model is proposed to estimate the average fragment size for a moving rock block when it impacts against an obstruction. Then, different forms of motion are studied, with various drop heights and slope angles for the moving rock block. The calculated results reveal that the average fragment size decreases as the drop height increases, whether for free-fall or for a sliding or rolling rock block, and the decline in size is rapid for low heights and slow for increasing heights in the corresponding curves. Moreover, the average fragment size also decreases as the slope angle increases for a slidingrock block. In addition, a rolling rock block has a higher degree of fragmentation than a sliding rock block, even for the same slope angle and block volume. Finally, to compare with others' results, the approximate number of fragments is estimated for each calculated example, and the results show that the proposed model is applicable to a relatively isotropic moving rock block. 展开更多
关键词 Rock block Rock fragmentation Rock movement process Crushing work ratio Average fragment size
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Generalised Closed-Form Symbol Error Rate Analysis for Orthogonal Space-Time Block Coded OFDM System
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作者 王旭东 吴楠 高春丽 《China Communications》 SCIE CSCD 2013年第9期155-164,共10页
In this paper,the Symbol Error Rate(SER)performance for Orthogonal Space-Time Block Coded(OSTBC)Orthogonal Frequency Division Multiplexing(OFDM)systems over Nakagami-m fading channels is analysed.A novel closed-form S... In this paper,the Symbol Error Rate(SER)performance for Orthogonal Space-Time Block Coded(OSTBC)Orthogonal Frequency Division Multiplexing(OFDM)systems over Nakagami-m fading channels is analysed.A novel closed-form SER expression is proposed,which incorporates the Gauss hypergeometric function and Appell hypergeometric function into the conventional Probability Density Function(PDF)approach.The proposed exact closed-form SER expression is a generalised solution since it perfectly captures OSTBCOFDM systems’performances when having different antenna configurations that employ various modulation schemes and which experience various fading conditions.Finally,Monte Carlo simulation results are provided to demonstrate the exact match between the simulation results and the proposed analytical expressions. 展开更多
关键词 OSTBC-OFDM closed-form SER Nakagami-m fading channel
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Some Properties of Two-mode Displaced Excited Squeezed Vacuum States
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作者 MENG Xiang-Guo WANG Ji-Suo LIANG Bao-Long 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第9期493-499,共7页
In this paper,two-mode displaced excited squeezed vacuum states (TDESVS) are constructed and theirnormalization and completeness are investigated.Using the entangled state representation and Weyl ordering formof the W... In this paper,two-mode displaced excited squeezed vacuum states (TDESVS) are constructed and theirnormalization and completeness are investigated.Using the entangled state representation and Weyl ordering formof the Wigner operator,the Wigner functions of TDESVS are obtained and the variations of Wigner functions withthe parameters m,n and r are investigated.Besides,two marginal distributions of Wigner functions of TDESVS areobtained,which exhibit some entangled properties of the two-particle's system in TDESVS. 展开更多
关键词 two-mode displaced excited squeezed vacuum state Weyl ordering Wigner function marginal distribution entangled state representation
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Seismic Behavior of Specially Shaped Column Joints with X-Shaped Reinforcement 被引量:3
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作者 戎贤 张健新 李艳艳 《Transactions of Tianjin University》 EI CAS 2013年第2期110-117,共8页
To investigate the seismic behavior of specially shaped column joints with X-shaped reinforcement,two groups of specimens with or without X-shaped reinforcement in joint core region were tested under constant axial co... To investigate the seismic behavior of specially shaped column joints with X-shaped reinforcement,two groups of specimens with or without X-shaped reinforcement in joint core region were tested under constant axial compression load and low reversed cyclic loading,which imitated low to moderate earthquake force.The seismic behavior of specially shaped column joints with X-shaped reinforcement in terms of bearing capacity,displacement,ductility,hysteretic curve,stiffness degradation and energy dissipation was studied and compared to that without Xshaped reinforcement in joint core region.With the damage estimation model,the accumulated damage was analyzed.The shearing capacity formula of specially shaped column joints reinforced by X-shaped reinforcement was proposed with a simple form.The test results show that X-shaped reinforcement is an effective measure for improving the seismic behavior of specially shaped column joints including deformation behavior,ductility and hysteretic characteristic.All specimens were damaged with gradual stiffness degeneration.In addition,X-shaped reinforcement in the joint core region is an effective way to lighten the degree of cumulated damage.The good seismic performance obtained from the specially shaped column joint with X-shaped reinforcement can be used in engineering applications.The test value is higher than the calculated value,which indicates that the formula is safe for the design of specially shaped column joints. 展开更多
关键词 specially shaped column JOINT low cyclic loading X-shaped reinforcement seismic behavior
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Research on the Application Security Isolation Model
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作者 Gong Lei Zhao Yong Liao Jianhua 《China Communications》 SCIE CSCD 2010年第6期153-156,共4页
Typical isolation models are studied and a New Application Security Isolation model called NASI is proposed, which is based on trusted computing technology and least privilege principle. This paper introduces the desi... Typical isolation models are studied and a New Application Security Isolation model called NASI is proposed, which is based on trusted computing technology and least privilege principle. This paper introduces the design ideas of NASI, gives out formal description and safety analysis for the model, and finally describes the implementation of prototype system based on NASI. 展开更多
关键词 application isolation security model application security protection
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Rules of distribution in a plastic zone of rocks surrounding a roadway affected by tectonic stress 被引量:5
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作者 LU Yan TU Shihao 《Mining Science and Technology》 EI CAS 2010年第1期47-52,共6页
In order to study the rules of distribution in a plastic zone of rocks, surrounding a roadway, affected by tectonic stress, we first analyzed the mechanics of a roadway affected by tectonic stress and derived a theore... In order to study the rules of distribution in a plastic zone of rocks, surrounding a roadway, affected by tectonic stress, we first analyzed the mechanics of a roadway affected by tectonic stress and derived a theoretical formula for the plastic zone of rocks surrounding a roadway. We also analyzed the distribution characteristics of the plastic zone under different levels of tectonic stress, vertical pressure, cohesion and friction angle of the surrounding rock. Secondly, we used numerical simulation to analyze the range and shape features of the plastic zone of rocks surrounding the roadway, given different tectonic stress levels. Finally we used a rock drilling detector to carry out field measurements on the broken state of rock surrounding the roadway at the –700 substation and channels in the Xinzhuang mine of the Shenhuo mining area. Given the measured ground stress, we analyzed the relationship between tectonic stress and the distribution of this plastic zone. Our results show that the range of the plastic zone at the top and bottom of the roadway increases with an increase in tectonic stress and this increase is especially obvious at the roadway corner. 展开更多
关键词 tectonic stress rock surrounding a roadway plastic zone
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A Generalized Form of Whitney's Theorem
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作者 CEN Yan-ming CEN Li-hui 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期75-78,共4页
Whitney's theorem is a famous theorem in the local singularity theory. In this paper, as an application of Malgrange preparation theorem, a generalized form of Whitney's theorem will be derived.
关键词 generalized of Whitney's theorem
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