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城市景观中的“联系线”——美国华盛顿哥伦比亚特区与上海浦东陆家嘴地区城市设计之比较
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作者 龚近方 《同济大学学报(社会科学版)》 2000年第S1期20-23,51,共5页
城市景观中的“联系线”是用线性空间要素组织城市景观的一种设计理论和方法。本文试对运用“联系线”组织城市景观的两个地块——美国华盛顿哥伦比亚特区与上海浦东陆家嘴地区的城市设计作一比较,以得到“联系线”理论在实践运用中的利... 城市景观中的“联系线”是用线性空间要素组织城市景观的一种设计理论和方法。本文试对运用“联系线”组织城市景观的两个地块——美国华盛顿哥伦比亚特区与上海浦东陆家嘴地区的城市设计作一比较,以得到“联系线”理论在实践运用中的利弊,并提出相应的调整策略。 展开更多
关键词 联系线 建筑 城市
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让“线段图”活起来——以“和倍问题”教学为例 被引量:1
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作者 魏雯 《小学教学参考》 2022年第14期64-66,共3页
画线段图是数学中一种非常重要的解题方法,线段图的准确表达能帮助学生分析并解决问题,引导学生理解各个量之间的关系,让学生感受问题解决中“线与线”之间的联系。教学中,教师应引导学生从自己的知识经验出发自主构建线段图,增强学生... 画线段图是数学中一种非常重要的解题方法,线段图的准确表达能帮助学生分析并解决问题,引导学生理解各个量之间的关系,让学生感受问题解决中“线与线”之间的联系。教学中,教师应引导学生从自己的知识经验出发自主构建线段图,增强学生运用线段图的自觉性。 展开更多
关键词 线段图 和倍问题 线多用 线线联系
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Decentralized Control Based on FNNSMC for Interconnected Uncertain Nonlinear Systems
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作者 达飞鹏 宋文忠 《Journal of Southeast University(English Edition)》 EI CAS 1998年第2期86-92,共7页
A new type controller, fuzzy neural networks sliding mode controller (FNNSMC), is developed for a class of large scale systems with unknown bounds of high order interconnections and disturbances. Although sliding mod... A new type controller, fuzzy neural networks sliding mode controller (FNNSMC), is developed for a class of large scale systems with unknown bounds of high order interconnections and disturbances. Although sliding mode control is simple and insensitive to uncertainties and disturbances, there are two main problems in the sliding mode controller (SMC): control input chattering and the assumption of known bounds of uncertainties and disturbances. The FNNSMC, which incorporates the fuzzy neural networks (FNN) and the SMC, can eliminate the chattering by using the continuous output of the FNN to replace the discontinuous sign term in the SMC. The bounds of uncertainties and disturbances are also not required in the FNNSMC design. The simulation results show that the FNNSMC has more robustness than the SMC. 展开更多
关键词 sliding mode control fuzzy neural networks interconnected nonlinear systems
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“110”的神通在哪里?
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作者 杨东鲁 《湖北社会科学》 CSSCI 1997年第12期35-35,共1页
关键词 密切联系群众 安机关 人民警察 舆论监督 工作方法 人民群众 依靠群众 工作作风 联系线
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ROBUST STABILIZATING FOR A OLASS OF UNOERTAIN NONLINEAR INTEROONNECTED SYSTEMS USING VARIABLE STRUCTURE CONTROL
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作者 姜斌 万健如 王先来 《Transactions of Tianjin University》 EI CAS 1999年第1期42-46,共5页
The robust stabilizating control problem for a class of uncertain nonlinear large-scale systems is discussed. Based on the theory of both input/output (I/O) linearization and decentralized variable structure control (... The robust stabilizating control problem for a class of uncertain nonlinear large-scale systems is discussed. Based on the theory of both input/output (I/O) linearization and decentralized variable structure control (VSC),two-level and decentralized variable structure control laws for this kind of systems are presented respectively,which achieve asymptotically stabilization despite the uncertainties and disturbances. At last,sirnulation of the disturbed two-pendulum system is given to illustrate the feasibility of proposed technique. 展开更多
关键词 nonlinear interconnected systems UNCERTAINTY STABILIZATION variable structure control input/output linearization
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An autonomic joint radio resource management algorithm in end-to-end reconfigurable system 被引量:1
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作者 林粤伟 《High Technology Letters》 EI CAS 2008年第3期238-244,共7页
This paper presents the multi-step Q-learning(MQL)algorithm as an autonomic approach to thejoint radio resource management(JRRM)among heterogeneous radio access technologies(RATs)in theB3G environment.Through the'... This paper presents the multi-step Q-learning(MQL)algorithm as an autonomic approach to thejoint radio resource management(JRRM)among heterogeneous radio access technologies(RATs)in theB3G environment.Through the'trial-and-error'on-line learning process,the JRRM controller can con-verge to the optimized admission control policy.The JRRM controller learns to give the best allocation foreach session in terms of both the access RAT and the service bandwidth.Simulation results show that theproposed algorithm realizes the autonomy of JRRM and achieves well trade-off between the spectrum utilityand the blocking probability comparing to the load-balancing algorithm and the utility-maximizing algo-rithm.Besides,the proposed algorithm has better online performances and convergence speed than theone-step Q-learning(QL)algorithm.Therefore,the user statisfaction degree could be improved also. 展开更多
关键词 joint radio resource management reinforcement learning AUTONOMIC end-to-end reconfigurability heterogeneous networks
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The Four Intersection-and-Difference Model for Line-Line Topological Relations
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作者 DENG Min LI Zhilin LI Guangqiang ZHANG Xuesong 《Geo-Spatial Information Science》 2007年第4期293-298,共6页
The description of line-line topological relations is still an unsolved issue although much effort has been done. The problem is involved in many practical applications such as spatial query, spatial analysis and cart... The description of line-line topological relations is still an unsolved issue although much effort has been done. The problem is involved in many practical applications such as spatial query, spatial analysis and cartographic generalization. To develop a sound and effective approach to describe line-line relations, it is first necessary to define the topology of an individual line, i.e., local topology. The concept of connective degree is used for the identification of topological differences in the geometric structure of a line. The general topological definition of a line is given, i.e., endpoints set and interior point set. This definition can be applied to the embedded spaces of different dimensions, whether co-dimension is equal to or larger than zero. On this basis, a generic model called the 4 intersection-and-difference is set up for the description of basic line-line topological relations, upon which a conceptual neighborhood graph is built with consideration of topological distance, it is concluded that the proposed model can represent the property of topological changes, and basic relations between line segments in IR^1 and IR^2. 展开更多
关键词 topological relations line object topological distance conceptual neighborhood CO-DIMENSION
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Power interconnected system clustering with advanced fuzzy C-mean algorithm 被引量:6
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作者 王洪梅 KIM Jae-Hyung +2 位作者 JUNG Dong-Yean LEE Sang-Min LEE Sang-Hyuk 《Journal of Central South University》 SCIE EI CAS 2011年第1期190-195,共6页
An advanced fuzzy C-mean (FCM) algorithm was proposed for the efficient regional clustering of multi-nodes interconnected systems. Due to various locational prices and regional coherencies for each node and point, m... An advanced fuzzy C-mean (FCM) algorithm was proposed for the efficient regional clustering of multi-nodes interconnected systems. Due to various locational prices and regional coherencies for each node and point, modified similarity measure was considered to gather nodes having similar characteristics. The similarity measure was needed to contain locafi0nal prices as well as regional coherency. In order to consider the two properties simultaneously, distance measure of fuzzy C-mean algorithm had to be modified. Regional clustering algorithm for interconnected power systems was designed based on the modified fuzzy C-mean algorithm. The proposed algorithm produces proper classification for the interconnected power system and the results are demonstrated in the example of IEEE 39-bus interconnected electricity system. 展开更多
关键词 fuzzy C-mean similarity measure distance measure interconnected system CLUSTERING
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Comparative analysis of coal and coal-shale intrinsic factors affecting spontaneous combustion 被引量:13
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作者 M. Onifade B. Genc 《International Journal of Coal Science & Technology》 EI 2018年第3期282-294,共13页
Coal and coal-shales tend to undergo spontaneous combustion under favourable atmospheric conditions. Spontaneous combustion liability index and intrinsic properties of coals and coal-shales varies between (above and ... Coal and coal-shales tend to undergo spontaneous combustion under favourable atmospheric conditions. Spontaneous combustion liability index and intrinsic properties of coals and coal-shales varies between (above and below) coal seams. The spontaneous combustion liability index (obtained from the Wits-Ehac Index) and intrinsic properties (obtained from proximate, ultimate, and petrographic analysis) of fourteen samples representative of in situ coal (bituminous) and fourteen coal-shales obtained in Witbank coalfield, South Africa were experimentally studied. Comparative analysis of the relationships between the spontaneous combustion liability index and intrinsic properties of coals and coalshales were established to evaluate their effects on self-heating potential. The intrinsic properties show linear relationship with spontaneous combustion liability and therefore, identifies the factors affecting spontaneous combustion of these materials. The influence of coal-shales intrinsic properties towards spontaneous combustion liability shows higher correlation coefficients than the coals. Both coals and coal-shales show inertinite maceral as major constituents than the vitrinite and liptinite macerals, hence the reactivity of inertinite macerals may show greater influence on spontaneous combustion liability. A definite positive or negative trends exists between the intrinsic properties and spontaneous combustion liability index. This research is part of a larger project which is considering the influence of intrinsic properties of coals and coal-shales on spontaneous combustion liability. 展开更多
关键词 Coal-shales Spontaneous combustion Liability index Statistical analysis and correlation coefficient
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The Structure and Stabilization Decom position of Linear Interconnected ControlSystem swith Multidelays
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作者 张新政 邓则明 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第4期53-58, ,共6页
This paper gives a structural concept for linear interconnected control systems with multidelays,which is based on equivalence method of lyapunovs frequency area, a sufficient \{criteria\} is obtained for the intercon... This paper gives a structural concept for linear interconnected control systems with multidelays,which is based on equivalence method of lyapunovs frequency area, a sufficient \{criteria\} is obtained for the interconnected stabilization of linear constant control system with multidelays,at the same time,the estimation of bound both time delays and parametric perturbation are given. 展开更多
关键词 multidelays interconnected control system stabilization decomposition equivalence method
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Application Scenarios and Enabling Technologies of 5G 被引量:13
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作者 YUAN Yifei ZHU Longming 《China Communications》 SCIE CSCD 2014年第11期69-79,共11页
Fast growth of mobile internet and internet-of-things has propelled the concept formation and research on 5G wireless communications systems which are to be standardized around 2020(IMT-2020).There will be diverse app... Fast growth of mobile internet and internet-of-things has propelled the concept formation and research on 5G wireless communications systems which are to be standardized around 2020(IMT-2020).There will be diverse application scenarios expected for 5G networks.Hence,key performance indicators(KPIs) of 5G systems would be very diverse,not just the peak data rate and average/edge spectral efficiency requirements as in previous generations.For each typical scenario,multiple technologies may be used independently or jointly to improve the transmission efficiency,to lower the cost,and to increase the number of connections,etc.Key enabling technologies are discussed which include massive MIMO,ultradense deployment specific techniques,nonorthogonal transmission,high frequency communications,etc. 展开更多
关键词 5G IMT-2020 ultra-dense networks massive MIMO non-orthogonal transmission
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A Method for Generating Contour Tree Based on Voronoi Interior Adjacency
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作者 QIAO Chaofei ZHAO Renliang +1 位作者 CHEN Jun CHEN Yunhao 《Geo-Spatial Information Science》 2005年第4期287-290,310,共5页
A contour tree is a good graphical tool for representing the spatial relations of contour lines and has many applications in map generalization, map annotation, terrain analysis, etc. A new method for generating conto... A contour tree is a good graphical tool for representing the spatial relations of contour lines and has many applications in map generalization, map annotation, terrain analysis, etc. A new method for generating contour trees by introducing a Voronoi based interior adjacency concept is proposed in this paper. The immediate interior adjacency set is employed to identify all of the children contours of each contour without contour elevations. It has advantages over existing methods such as the geometric method and the region growing based method. 展开更多
关键词 spatial relations of contour lines contour tree Voronoi interior adjacency set
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The Design of Internet of Things Smart Home System based on S3C2440 and Zigbee 被引量:2
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作者 Wenjing Zhang 《International Journal of Technology Management》 2013年第7期81-83,共3页
In order to achieve the smart home system for remote management and wireless transmission function in the smart home networking system design, the article will combined with ARM technology and ZigBee wireless network ... In order to achieve the smart home system for remote management and wireless transmission function in the smart home networking system design, the article will combined with ARM technology and ZigBee wireless network technology based on samsung's $3C2440 chip and some related peripheral devices to form into home gateway of the system control platform, and the home control network using the internal ZigBee wireless network technologies. Practice has proved that the system is stable, is worth promoting. 展开更多
关键词 NETWORK embedded system intelligent home furnishing ZIGBEE SC2440
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The Linear Stability of a Solution of a Parallel Redundant Repairable System 被引量:1
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作者 王鸿燕 赵占锋 亓正申 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第3期458-463,共6页
In this paper,the solution of a parallel redundant repairable system is investigated.by using the method of functional analysis.Especially,the linear semigroups of operator theory on Banach space,we prove the existenc... In this paper,the solution of a parallel redundant repairable system is investigated.by using the method of functional analysis.Especially,the linear semigroups of operator theory on Banach space,we prove the existence of the strictly dominant eigenvalue,and show the linear stability of solution. 展开更多
关键词 REDUNDANT repairable system strictly dominant eigenvalue linear stability
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Calculation of Gas-Liquid Critical Curves for Binary Systems Containing Methane
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作者 朱荣娇 李洪玲 +2 位作者 郝纪双 李贺松 田宜灵 《Transactions of Tianjin University》 EI CAS 2009年第4期276-282,共7页
The critical curves for binary systems of methane combined with nitrogen, carbon monoxide, carbon dioxide, ethane, propane, butane and water at temperatures from 125 K to 650 K and pressures from 3.5 MPa to 250 MPa we... The critical curves for binary systems of methane combined with nitrogen, carbon monoxide, carbon dioxide, ethane, propane, butane and water at temperatures from 125 K to 650 K and pressures from 3.5 MPa to 250 MPa were calculated by using Heilig-Franck equation of state. This equation of state contains a repulsion term and an attraction term for intermolecular interaction. With pairwise combination rules for these potentials, three adjustable parameters are needed. The results showed that the critical curves of the former six binary systems belonged to type I, and CH4+H2O system belonged to type III. The calculated data were compared with the experimental data,which yielded good results for the pressure-temperature, pressure-composition and temperature-composition behaviors of the seven systems. Moreover, the values of the adjustable parameters were obtained from the calculation of the critical curves. They can also be used for other relevant calculation. 展开更多
关键词 critical curves binary systems METHANE CALCULATION
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Robust Adaptive FTC against Sensor Fault
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作者 Amina Challouf Christophe Aubrun +1 位作者 Adel Tellili Mohamed Naceur Abdelkrim 《Computer Technology and Application》 2012年第1期56-68,共13页
This paper addresses the problem of robust Fault-Tolerant (FT) design for large-scale systems. This particular class constitutes complex system which can be decomposed into N-interconnected subsystems. Special atten... This paper addresses the problem of robust Fault-Tolerant (FT) design for large-scale systems. This particular class constitutes complex system which can be decomposed into N-interconnected subsystems. Special attention is paid to two different design architectures of an Active Fault-Tolerant Control (AFTC). An AFTCS is characterized by an online Fault Detection and Isolation (FDI) process and a control reconfiguration mechanism. As the AFTC system offers the possibility to choose different controllers, the controller may be the most appropriate choice for the faulty situation and obtaining better performance. The goal of each adaptive controller is to accommodate sensor anomalies. Continuous, Linear and Time Invariant (LTI) complex system with faulty sensors and external disturbances is proposed. This study focuses on two different internal structures of the system. In this paper the direct adaptive method based on feedback controller design is applied both centralized and decentralized architectures. The controller gain is updated online using an adaptive law which takes into account the estimation of the faults and the disturbances. Then from the both classes of systems structures the adaptation controller performances, in terms of stability and fault effect rejection capability, are studied and compared. The proposed techniques are finally evaluated in the light of a simulation for a centralized interconnected system that can be decomposed into N-subsystems with some strong interconnections. 展开更多
关键词 Adaptive control centralized control complex system decentralized control fault-tolerant control (FTC) N-Interconnected subsystems robust control sensor failure.
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Mobile Internet Applications:Impact on Future Wireless Communications System 被引量:1
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作者 Gao Youjun Yang Ning +1 位作者 Cui Chunfeng Kimba Dit Adamou Boubacar 《China Communications》 SCIE CSCD 2012年第4期20-25,共6页
Based on the analysis of application status in real network,the trace model of some typical mobile Internet applications data is given and their impact on 2G/3G network is discussed in this paper.Furthermore,in order ... Based on the analysis of application status in real network,the trace model of some typical mobile Internet applications data is given and their impact on 2G/3G network is discussed in this paper.Furthermore,in order to support the mobile Internet application efficiently in future,the issues including the impact on the Long Term Evolution (LTE-A) system and some potential solutions for performance optimization are studied.Based on the trace data model of IM traffic,the performacne evaluaiton of LTE-A system shows that some specific configuration machanisms can play an important role in improving network system efficiency in the case of IM traffic. 展开更多
关键词 mobile Internet traffic LTE-A system performance optimization Mobile QQ
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New sigma point filtering algorithms for nonlinear stochastic systems with correlated noises 被引量:2
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作者 王小旭 潘泉 +1 位作者 程咏梅 赵春晖 《Journal of Central South University》 SCIE EI CAS 2012年第4期1010-1020,共11页
New sigma point filtering algorithms, including the unscented Kalman filter (UKF) and the divided difference filter (DDF), are designed to solve the nonlinear filtering problem under the condition of correlated no... New sigma point filtering algorithms, including the unscented Kalman filter (UKF) and the divided difference filter (DDF), are designed to solve the nonlinear filtering problem under the condition of correlated noises. Based on the minimum mean square error estimation theory, the nonlinear optimal predictive and correction recursive formulas under the hypothesis that the input noise is correlated with the measurement noise are derived and can be described in a unified framework. Then, UKF and DDF with correlated noises are proposed on the basis of approximation of the posterior mean and covariance in the unified framework by using unscented transformation and second order Stirling's interpolation. The proposed UKF and DDF with correlated noises break through the limitation that input noise and measurement noise must be assumed to be uneorrelated in standard UKF and DDF. Two simulation examples show the effectiveness and feasibility of new algorithms for dealing with nonlinear filtering issue with correlated noises. 展开更多
关键词 nonlinear system correlated noise sigma point unscented Kalman filter divided difference filter
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Modern Social Communications as a Bifurcation Point of Traditional Social Institutes
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作者 S. A. Sharonova Ch. I. lldarhanova 《Sociology Study》 2014年第5期471-480,共10页
Impact of Internet Technologies increases importance of changes in the system of social communication creating a stressful situation for the functioning of traditionally established social institutions. New phenomena ... Impact of Internet Technologies increases importance of changes in the system of social communication creating a stressful situation for the functioning of traditionally established social institutions. New phenomena such as priest's and saints' online pages, represent significant deviation from historical practice, bring certain dissonance to the activities of the church. On one hand, church has to use modern communication channel, on the other hand, effects of online translation of confessional relations are not predictable. Open global socieW requires certain universalization of education, but professional communications are faced not only with a problem of language barrier, but also with national culture. School of thought, formed in traditions of particular cultural outlook, risks losing its face to the loss of national characteristics of the education system. Institute of Administration is also experiencing certain amount of stress. 展开更多
关键词 BIFURCATION bifurcation point social communication EDUCATION
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直线 射线 线段
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作者 田枰 《初中生辅导》 2003年第16期47-48,共2页
关键词 线 线 线 端点 大写字母 延伸性 联系线 相反方向 小写字母 中学
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