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华盛顿邮报的结网式融合实践探究 被引量:3
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作者 林昱君 《新闻与写作》 CSSCI 北大核心 2019年第2期102-106,共5页
华盛顿邮报作为美国传统媒体的代表,在融合实践道路上取得了较为瞩目的成绩。其转型成功得力于不同时期对媒介融合的正确选择。本文探究华盛顿邮报的结网式媒介融合之路,探讨其通过稳健的节点建设、广泛的联系构建、立体的内容结网以及... 华盛顿邮报作为美国传统媒体的代表,在融合实践道路上取得了较为瞩目的成绩。其转型成功得力于不同时期对媒介融合的正确选择。本文探究华盛顿邮报的结网式媒介融合之路,探讨其通过稳健的节点建设、广泛的联系构建、立体的内容结网以及技术与管理的多维度融合所取得成功的原因。我国媒介可以借鉴华盛顿邮报的融合经验,通过"迟到"的布局、高效的结网和第三方互联网生态进行实践探索。 展开更多
关键词 华盛顿邮报 结网式 媒介融合
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Transition of plasticity and fracture mode of Zr-Al-Ni-Cu bulk metallic glasses with network structures 被引量:1
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作者 蔡安辉 丁大伟 +4 位作者 安伟科 周果君 罗云 李江鸿 彭勇宜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2617-2623,共7页
Effect of network structure on plasticity and fracture mode of Zr?Al?Ni?Cu bulk metallic glasses (BMGs) was investigated. The microstructures of transversal and longitudinal sections were exposed by chemical etch... Effect of network structure on plasticity and fracture mode of Zr?Al?Ni?Cu bulk metallic glasses (BMGs) was investigated. The microstructures of transversal and longitudinal sections were exposed by chemical etching and observed by scanning electron microscopy (SEM). The mechanical properties were examined by room-temperature uniaxial compression test. The results show that both plasticity and fracture mode are significantly affected by the network structure and the alteration occurs when the size of the network structure reaches up to a critical value. When the cell size (dc) of the network structure is ~3μm, Zr-based BMGs characterize in plasticity that decreases with increasingdc. The fracture mode gradually transforms from single 45° shear fracture to double 45° shear fracture and then cleavage fracture with increasingdc. In addition, the mechanisms of the transition of the plasticity and the fracture mode for these Zr-based BMGs are also discussed. 展开更多
关键词 bulk metallic glass PLASTICITY fracture mode network structure
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UPWIND SCHEME FOR IDEAL 2-D MHD FLOWS BASED ON UNSTRUCTURED MESH 被引量:1
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作者 潘勇 王江峰 伍贻兆 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第1期1-7,共7页
An upwind scheme based on the unstructured mesh is developed to solve ideal 2-D magnetohydrodynamics (MHD) equations. The inviscid fluxes are approximated by using the modified advection upstream splitting method (... An upwind scheme based on the unstructured mesh is developed to solve ideal 2-D magnetohydrodynamics (MHD) equations. The inviscid fluxes are approximated by using the modified advection upstream splitting method (AUSM) scheme, and a 5-stage explicit Runge-Kutta scheme is adopted in the time integration. To avoid the influence of the magnetic field divergence created during the simulation, the hyperbolic divergence cleaning method is introduced. The shock-capturing properties of the method are verified by solving the MHD shock-tube problem. Then the 2-D nozzle flow with the magnetic field is numerically simulated on the unstructured mesh. Computational results demonstrate the effects of the magnetic field and agree well with those from references. 展开更多
关键词 ideal magnetohydrodynamics equation unstructured mesh advection upstream splitting method(AUSM) scheme divergence cleaning
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高三数学六步复习法
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作者 魏向阳 姚志勇 《渤海大学学报(自然科学版)》 CAS 1997年第3期59-61,共3页
依钢靠本的三基复习;重点知识,重点方法,重点技巧前挂后联的专题复习:小章节的知识查缺补漏练习;大章节的知识查缺补漏及局部综合练习:纵横交叉的模拟训练;学生的自由复习。
关键词 结网式 线清点实 接轨平稳 全方位
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Alpha-reliable combined mean traffic equilibrium model with stochastic travel times 被引量:5
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作者 张文义 关伟 +1 位作者 宋丽英 孙会君 《Journal of Central South University》 SCIE EI CAS 2013年第12期3770-3778,共9页
Based on the reliability budget and percentile travel time(PTT) concept, a new travel time index named combined mean travel time(CMTT) under stochastic traffic network was proposed. CMTT here was defined as the convex... Based on the reliability budget and percentile travel time(PTT) concept, a new travel time index named combined mean travel time(CMTT) under stochastic traffic network was proposed. CMTT here was defined as the convex combination of the conditional expectations of PTT-below and PTT-excess travel times. The former was designed as a risk-optimistic travel time index, and the latter was a risk-pessimistic one. Hence, CMTT was able to describe various routing risk-attitudes. The central idea of CMTT was comprehensively illustrated and the difference among the existing travel time indices was analyzed. The Wardropian combined mean traffic equilibrium(CMTE) model was formulated as a variational inequality and solved via an alternating direction algorithm nesting extra-gradient projection process. Some mathematical properties of CMTT and CMTE model were rigorously proved. Finally, a numerical example was performed to characterize the CMTE network. It is founded that that risk-pessimism is of more benefit to a modest(or low) congestion and risk network, however, it changes to be risk-optimism for a high congestion and risk network. 展开更多
关键词 travel behavior risk attitude travel time reliability combined mean travel time wardropian user equilibrium
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A FVCOM-Based Unstructured Grid Wave, Current,Sediment Transport Model,I.Model Description and Validation 被引量:16
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作者 WU Lunyu CHEN Changsheng +3 位作者 GUO Peifang SHI Maochong QI Jianhua GE Jianzhong 《Journal of Ocean University of China》 SCIE CAS 2011年第1期1-8,共8页
An effort was made to couple FVCOM (a three-dimensional (3D),unstructured grid,Finite Volume Coastal Ocean Model) and FVCOM-SWAVE (an unstructured grid,finite-volume surface wave model) for the study of nearshore ocea... An effort was made to couple FVCOM (a three-dimensional (3D),unstructured grid,Finite Volume Coastal Ocean Model) and FVCOM-SWAVE (an unstructured grid,finite-volume surface wave model) for the study of nearshore ocean processes such as tides,circulation,storm surge,waves,sediment transport,and morphological evolution.The coupling between FVCOM and FVCOM-SWAVE was achieved through incorporating 3D radiation stress,wave-current-sediment-related bottom boundary layer,sea surface stress parameterizations,and morphology process.FVCOM also includes a 3D sediment transport module.With accurate fitting of irregular coastlines,the model provides a unique tool to study sediment dynamics in coastal ocean,estuaries,and wetlands where local geometries are characterized by inlets,islands,and intertidal marsh zones.The model was validated by two standard benchmark tests: 1) spectral waves approaching a mild sloping beach and 2) morphological changes of seabed in an idealized tidal inlet.In Test 1,model results were compared with both analytical solutions and laboratory experiments.A further comparison was also made with the structured grid Regional Ocean Model System (ROMS),which provides an insight into the performance of the two models with the same open boundary forcing. 展开更多
关键词 FVCOM COUPLING radiation stress wave-current-sediment-related bottom boundary layer MORPHOLOGY
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An Open Architecture for Converged Internet of Things 被引量:3
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作者 邹俊伟 吴岳辛 张晓莹 《China Communications》 SCIE CSCD 2011年第1期151-155,共5页
An open architecture for converged Internet of Things (IoT) is proposed in this paper.By using this model,the various and huge amount of data can be converted into converged data and then encapsulated as service packa... An open architecture for converged Internet of Things (IoT) is proposed in this paper.By using this model,the various and huge amount of data can be converted into converged data and then encapsulated as service packages.Moreover,a Representational State Transfer (REST) platform has been implemented in the lab environment.The merit of this architecture is the enhancement of data efficiency.Experimental results are provided to show the benefits of the proposed architecture. 展开更多
关键词 Internet of Things Representational State Transfer (REST) converged data
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Application of extension neural network to safety status pattern recognition of coalmines 被引量:6
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作者 周玉 W.Pedrycz 钱旭 《Journal of Central South University》 SCIE EI CAS 2011年第3期633-641,共9页
In order to accurately and quickly identify the safety status pattern of coalmines,a new safety status pattern recognition method based on the extension neural network (ENN) was proposed,and the design of structure of... In order to accurately and quickly identify the safety status pattern of coalmines,a new safety status pattern recognition method based on the extension neural network (ENN) was proposed,and the design of structure of network,the rationale of recognition algorithm and the performance of proposed method were discussed in detail.The safety status pattern recognition problem of coalmines can be regard as a classification problem whose features are defined in a range,so using the ENN is most appropriate for this problem.The ENN-based recognition method can use a novel extension distance to measure the similarity between the object to be recognized and the class centers.To demonstrate the effectiveness of the proposed method,a real-world application on the geological safety status pattern recognition of coalmines was tested.Comparative experiments with existing method and other traditional ANN-based methods were conducted.The experimental results show that the proposed ENN-based recognition method can identify the safety status pattern of coalmines accurately with shorter learning time and simpler structure.The experimental results also confirm that the proposed method has a better performance in recognition accuracy,generalization ability and fault-tolerant ability,which are very useful in recognizing the safety status pattern in the process of coal production. 展开更多
关键词 safety status pattern recognition extension neural network coal mines
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Spatial Structural Pattern and Vulnerability of China-Japan-Korea Shipping Network 被引量:17
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作者 GUO Jianke WANG Shaobo +1 位作者 WANG Dandan LIU Tianbao 《Chinese Geographical Science》 SCIE CSCD 2017年第5期697-708,共12页
The economies of China-Japan-Korea (CJK) are complementary, with their proximity resulting in the three countries having a high degree of interdependence with respect to trade. Currently, trade among these countries... The economies of China-Japan-Korea (CJK) are complementary, with their proximity resulting in the three countries having a high degree of interdependence with respect to trade. Currently, trade among these countries relies mainly on port-centered shipping. The development of the shipping network is integral for in-depth integration of CJK trade. This paper analyzes the overall characteristics, centrality, spatial structure, and vulnerability of the CJK shipping network using the methods of complex network analysis, blocking flow theory, and interruption and deletion of hub ports. The main findings are as follows: 1) The CJK shipping network has a small average path length and clustering coefficient, and its degree distribution follows a power-law distribution, which make the network present obvious characteristics of a Barabasi-Albert scale-free. 2) The characteristics of the multi-center point of the CJK shipping network can alleviate traffic pressure. At the same time, the network shows a clear hierarchy in the port transportation system, with cargo transport relying mainly on the ‘hub port-hub port' connection. 3) The CJK shipping network is relatively stable. Compared with ports in Japan and Korea, the main hub ports in China have a greater impact on the stability of the shipping network, in particular those ports of the central coastal region, including Shanghai, Ningbo, and Lianyungang. 展开更多
关键词 complex network blocking flow theory Barabhsi-Albert scale-free network regional differences China-Japan-Korea
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Cognitive Network Management in Internet of Things 被引量:5
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作者 覃毅芳 沈强 +4 位作者 林涛 赵志军 唐晖 慈松 冯志勇 《China Communications》 SCIE CSCD 2011年第1期1-7,共7页
The wide variety of smart embedded computing devices and their increasing number of applications in our daily life have created new op- portunities to acquire knowledge from the physical world anytime and anywhere, wh... The wide variety of smart embedded computing devices and their increasing number of applications in our daily life have created new op- portunities to acquire knowledge from the physical world anytime and anywhere, which is envisioned as the"Internet of Things" (IoT). Since a huge number of heterogeneous resources are brought in- to IoT, one of the main challenges is how to effi- ciently manage the increasing complexity of IoT in a scalable, flexNle, and autonomic way. Further- more, the emerging IoT applications will require collaborations among loosely coupled devices, which may reside in various locations of the Inter- net. In this paper, we propose a new IoT network management architecture based on cognitive net- work management technology and Service-Orien- ted Architecture to provide effective and efficient network management of loT. 展开更多
关键词 cognitive network management Serv- ice-Oriented Architecture (SOA) Internet of Things policy-based network management
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A CENTRAL-STAGE BUFFERED THREE-STAGE CLOS SWITCHING FABRIC AND THE SCHEDULING ALGORITHM
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作者 Hu Yuxiang Ma Xiangjie Lan Julong Wang Haoxue 《Journal of Electronics(China)》 2009年第1期113-119,共7页
Current MSM switching fabric has poor performance under unbalanced traffic. This paper presents an alternative, novel Central-stage Buffered Three-stage Clos switching (CB-3Clos) fabric and proves that this fabric can... Current MSM switching fabric has poor performance under unbalanced traffic. This paper presents an alternative, novel Central-stage Buffered Three-stage Clos switching (CB-3Clos) fabric and proves that this fabric can emulate output queuing switch without any speedup. By analyzing the condition to satisfy the central-stage load-balance, this paper also proposes a Central-stage Load-balanced-based Distributed Scheduling algorithm (CLDS) for CB-3Clos. The results show that, compared with Concurrent Round-Robin based Dispatching (CRRD) algorithm based on MSM, CLDS algorithm has high throughput irrespective with the traffic model and better performance in mean packet delay. 展开更多
关键词 Three-stage Clos switching fabric Central-stage buffered Distributed scheduling Loadbalance
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Comprehensive Analysis of Caching Performance under Probabilistic Traffic Patterns for Content Centric Networking
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作者 Dabin Kim Young-Bae Ko Sung-Hwa Lim 《China Communications》 SCIE CSCD 2016年第3期127-136,共10页
The phenomenon of data explosion represents a severe challenge for the upcoming big data era.However,the current Internet architecture is insufficient for dealing with a huge amount of traffic owing to an increase in ... The phenomenon of data explosion represents a severe challenge for the upcoming big data era.However,the current Internet architecture is insufficient for dealing with a huge amount of traffic owing to an increase in redundant content transmission and the end-point-based communication model.Information-centric networking(ICN)is a paradigm for the future Internet that can be utilized to resolve the data explosion problem.In this paper,we focus on content-centric networking(CCN),one of the key candidate ICN architectures.CCN has been studied in various network environments with the aim of relieving network and server burden,especially in name-based forwarding and in-network caching functionalities.This paper studies the effect of several caching strategies in the CCN domain from the perspective of network and server overhead.Thus,we comprehensively analyze the in-network caching performance of CCN under several popular cache replication methods(i.e.,cache placement).We evaluate the performance with respect to wellknown Internet traffic patterns that follow certain probabilistic distributions,such as the Zipf/Mandelbrot–Zipf distributions,and flashcrowds.For the experiments,we developed an OPNET-based CCN simulator with a realistic Internet-like topology. 展开更多
关键词 content-centric networking probabilistic Internet traffic patterns caching performance analysis OPNET
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Calculation of Minimal Dominating Set in Wireless Sensor Network with Host Switch-on/off
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作者 张静 贾春福 《Transactions of Tianjin University》 EI CAS 2010年第4期279-283,共5页
This paper proposes a simple and efficient distributed algorithm for calculating minimal dominating set in wireless sensor network. This method can avoid maintaining the connectivities between backbone hosts. Consider... This paper proposes a simple and efficient distributed algorithm for calculating minimal dominating set in wireless sensor network. This method can avoid maintaining the connectivities between backbone hosts. Considering that the hosts in mobile networks have different characteristics, this paper proposes a method of calculating minimal dominating set with weight. The nodes can be chosen to form a minimal dominating set when the network topology changes. For the host switch on/off operation, the updating algorithm was provided. The change in the status of a hostaffects only the status of hosts in the restricted vicinity. Simulation results show that the proposed method can ensure fewer dominators but with higher weight to form the minimal dominating set and the nodes can be adaptive to the changes of network topology. 展开更多
关键词 wireless sensor network virtual backbone minimal dominating set switch-on/off
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The Design of PBL Network Teaching System based on Multi-Agent
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作者 Ke Yu Xiao hong Li Yihua Du Feng Wang Nian Ye 《International Journal of Technology Management》 2013年第7期55-60,共6页
With the utilization of computer technology and network technology in building network teaching system approaching perfection, PBL teaching model is gradually applied to network teaching. On the basis of PBL teaching ... With the utilization of computer technology and network technology in building network teaching system approaching perfection, PBL teaching model is gradually applied to network teaching. On the basis of PBL teaching theory, this paper proposes a network teaching system based on PBL via network teaching model, using C/S structure and Java language to develop the prototype model and adding multi-agent application level to C/S structure in system designing in order to meet the requirements of the utilization of PBL method in network teaching. This new system successfully implements the innovative application of a problem-based network teaching. 展开更多
关键词 MULTI-AGENT PBL Online Education System Design
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Research on Energy Decision System based on Network Technology
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作者 Quan Li 《International Journal of Technology Management》 2013年第1期46-48,共3页
This paper analyzes the C/S structure and B/S structure of their own characteristics, building energy decision support system based on network technology, elaborated Web GIS and database connections and other technica... This paper analyzes the C/S structure and B/S structure of their own characteristics, building energy decision support system based on network technology, elaborated Web GIS and database connections and other technical principles and applications. Mixed B/S structure mode development to achieve information management, energy consumption is forecast to show the query using the amomat of energy, energy supply and demand dynamic equilibrimn analysis and other functions, with simple, efficient, easy to operate and so on, and has good scalability and maintainability. 展开更多
关键词 Web technologies Mixed B/S structure Energy Decision Support System
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中学历史“三段式”教学尝试
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作者 潘远新 《武汉市教育科学研究院学报》 2001年第8期64-64,共1页
我们所说的“三段式”,是指把一堂课分成三段进行教学。1.“读”。约十分钟左右。教师提出阅读思考题,组织学生认真阅读本节课教材,并允许讨论,让学生感知知识。2.“理”。约二十分钟左右。通过教师的启发、点拨、归纳,师生共同活动,对... 我们所说的“三段式”,是指把一堂课分成三段进行教学。1.“读”。约十分钟左右。教师提出阅读思考题,组织学生认真阅读本节课教材,并允许讨论,让学生感知知识。2.“理”。约二十分钟左右。通过教师的启发、点拨、归纳,师生共同活动,对教材知识结构进行串线结网式的整理,着重弄清重点和难点,让学生对知识加深理解和记忆。3.“练”。约十分钟左右。组织学生进行形式多样的练习,以求当堂强化概念,巩固记忆,培养学生应用知识的能力。以上教学程序不仅是发展、培养学生能力的过程。 展开更多
关键词 中学历史 组织学 教学尝试 培养学生能力 加深理解 知识 学生学习 教学程序 结网式 教师
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Do networks of social interactions reflect patterns of kinship? 被引量:1
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作者 Joah R. MADDEN Johanna F. NIELSEN Tim H. CLUTTON-BROCK 《Current Zoology》 SCIE CAS CSCD 2012年第2期319-328,共10页
The underlying kin structure of groups of animals may be glimpsed from patterns of spatial position or temporal as- sociation between individuals, and is presumed to facilitate inclusive fitness benefits. Such structu... The underlying kin structure of groups of animals may be glimpsed from patterns of spatial position or temporal as- sociation between individuals, and is presumed to facilitate inclusive fitness benefits. Such structure may be evident at a finer, behavioural, scale with individuals preferentially interacting with kin. We tested whether kin structure within groups of meerkats Suricata suricatta matched three forms of social interaction networks: grooming, dominance or foraging competitions. Networks of dominance interactions were positively related to networks of kinship, with close relatives engaging in dominance interactions with each other. This relationship persisted even after excluding the breeding dominant pair and when we restricted the kinship network to only include links between first order kin, which are most likely to be able to discern kin through simple rules of thumb. Conversely, we found no relationship between kinship networks and either grooming networks or networks of foraging competitions. This is surprising because a positive association between kin in a grooming network, or a negative association be- tween kin in a network of foraging competitions offers opportunities for inclusive fitness benefits. Indeed, the positive association between kin in a network of dominance interactions that we did detect does not offer clear inclusive fitness benefits to group members. We conclude that kin structure in behavioural interactions in meerkats may be driven by factors other than indirect fit- ness benefits, and that networks of cooperative behaviours such as grooming may be driven by direct benefits accruing to indi- viduals perhaps through mutualism or manipulation 展开更多
关键词 Social network KINSHIP Social structure GROOMING DOMINANCE MEERKATS
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Computational Method for Prestress Developing of Tensile Cable-Net Structures
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作者 赵俊钊 陈务军 付功义 《Journal of Shanghai Jiaotong university(Science)》 EI 2013年第2期197-204,共8页
The prestress developing of tensile cable-net structures is a state transforming process from the initial unstressed state to the final prestressed state, and it is rather complicated because the elastic deformation i... The prestress developing of tensile cable-net structures is a state transforming process from the initial unstressed state to the final prestressed state, and it is rather complicated because the elastic deformation is normally coupled with the kinematic mechanism movement. Firstly, the basic equations of prestress developing by moving boundary joint are derived from the total potential energy equation. Secondly, the presumed initial tension is proposed to impose into the elements and avoid the singularity of global stiffness matrix. And the self-stress mode which is calculated from the equilibrium matrix with singular vMue decomposition is employed as basically presumed initial tension. By applying boundary movement increment, an iterative computation is developed to calculate the updating geometric configuration and tension evolution. Finally, the MATLAB program is coded from the presented method, and numerical examples indicate that this computational method is effective and has theoretical significance and valuable guide to design and construction of tensile cable-net structure. 展开更多
关键词 tensile cable-net structures prestress developing presumed initial tension self-stress mode singular value decomposition
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h-P Finite Element Approximation for Full-Potential Electronic Structure Calculations 被引量:1
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作者 Yvon MADAY 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2014年第1期1-24,共24页
The(continuous) finite element approximations of different orders for the computation of the solution to electronic structures were proposed in some papers and the performance of these approaches is becoming appreciab... The(continuous) finite element approximations of different orders for the computation of the solution to electronic structures were proposed in some papers and the performance of these approaches is becoming appreciable and is now well understood.In this publication,the author proposes to extend this discretization for full-potential electronic structure calculations by combining the refinement of the finite element mesh,where the solution is most singular with the increase of the degree of the polynomial approximations in the regions where the solution is mostly regular.This combination of increase of approximation properties,done in an a priori or a posteriori manner,is well-known to generally produce an optimal exponential type convergence rate with respect to the number of degrees of freedom even when the solution is singular.The analysis performed here sustains this property in the case of Hartree-Fock and Kohn-Sham problems. 展开更多
关键词 Electronic structure calculation Density functional theory Hartree-Fock model Kohn-Sham model Nonlinear eigenvalue problem h - Pversion Finite element method
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A partition-of-unity based three-node triangular element with continuous nodal stress using radial-polynomial basis functions
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作者 YANG YongTao ZHENG Hong XU DongDong 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2017年第10期1518-1536,共19页
A partition-of-unity (PU) based "FE-Meshfree" three-node triangular element (Trig3-RPIM) was recently developed for linear elastic problems. This Trig3-RPIM element employs hybrid shape functions that combine th... A partition-of-unity (PU) based "FE-Meshfree" three-node triangular element (Trig3-RPIM) was recently developed for linear elastic problems. This Trig3-RPIM element employs hybrid shape functions that combine the shape functions of three-node triangular element (Trig3) and radial-polynomial basis functions for the purpose of synergizing the merits of both finite element method and meshfree method. Although Trig3-RPIM element is capable of obtaining higher accuracy and convergence rate than the Trig3 element and four-node iso-parametric quadrilateral element without adding extra nodes or degrees of freedom (DOFs), the nodal stress field through Trig3-RP1M element is not continuous and extra stress smooth operations are still needed in the post processing stage. To further improve the property of Trig3-RPIM element, a new PU-based triangular element with continuous nodal stress, called Trig3-RPIMcns, is developed. Numerical examples including several linear, free vibration and forced vibration test problems, have confirmed the correctness and feasibility of the proposed Trig3-RPIMcns element. 展开更多
关键词 partition of unity FE-Meshfree element Trig3-RPlMcns mesh distortion radial-polynomial basis functions
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