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Feature combination via importance-inhibition analysis
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作者 杨思春 高超 +2 位作者 姚佳岷 戴新宇 陈家骏 《Journal of Southeast University(English Edition)》 EI CAS 2013年第1期22-26,共5页
A new method for combining features via importance-inhibition analysis (IIA) is described to obtain more effective feature combination in learning question classification. Features are combined based on the inhibiti... A new method for combining features via importance-inhibition analysis (IIA) is described to obtain more effective feature combination in learning question classification. Features are combined based on the inhibition among features as well as the importance of individual features. Experimental results on the Chinese questions set show that, the IIA method shows a gradual increase in average and maximum accuracies at all feature combinations, and achieves great improvement over the importance analysis(IA) method on the whole. Moreover, the IIA method achieves the same highest accuracy as the one by the exhaustive method, and further improves the performance of question classification. 展开更多
关键词 question answering system questionclassification feature combination importance-inhibitionanalysis
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Tactical planning and optimization of a milk run system of parts pickup for an engine manufacturer 被引量:1
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作者 伊俊敏 周晶 +1 位作者 高晓亮 施挺 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期99-104,共6页
A real-life milk run system designing problem of an engine manufacturer adopted JIT(just-in-time)production is studied.In the process of milk run system planning and design,the supply base is identified and a supplier... A real-life milk run system designing problem of an engine manufacturer adopted JIT(just-in-time)production is studied.In the process of milk run system planning and design,the supply base is identified and a supplier site map is plotted for an arrangement of routes on which parts are periodically collected in a JIT manner from many scattered suppliers.With unit load designing,vehicle choosing and fleet sizing,pickup routing,vehicle assigning and scheduling problems are studied.Among these problems,a CVRP problem is identified and formulated as the key optimization in designing this milk run system,and it is solved through an optimization process.This tactical planning and optimization process gives a good solution to the real problem,and may shed light on the planning of similar systems. 展开更多
关键词 milk run vehicle routing problem JUST-IN-TIME system planning
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A Class of Nonlocal Boundary Value Problems for Elliptic Systems in Unbounded Domains
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作者 莫嘉琪 张汉林 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第3期29-33,共5页
A class of nonlocal boundary value probl em s for elliptic systems in the unbounded domains are considered. Under suitable c onditions, the existence of solution and the comparison theorem for the boundary value prob... A class of nonlocal boundary value probl em s for elliptic systems in the unbounded domains are considered. Under suitable c onditions, the existence of solution and the comparison theorem for the boundary value problems are studied. 展开更多
关键词 elliptic system boundary value problem c omparison theorem
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Question classification in question answering based on real-world web data sets
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作者 袁晓洁 于士涛 +1 位作者 师建兴 陈秋双 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期272-275,共4页
To improve question answering (QA) performance based on real-world web data sets,a new set of question classes and a general answer re-ranking model are defined.With pre-defined dictionary and grammatical analysis,t... To improve question answering (QA) performance based on real-world web data sets,a new set of question classes and a general answer re-ranking model are defined.With pre-defined dictionary and grammatical analysis,the question classifier draws both semantic and grammatical information into information retrieval and machine learning methods in the form of various training features,including the question word,the main verb of the question,the dependency structure,the position of the main auxiliary verb,the main noun of the question,the top hypernym of the main noun,etc.Then the QA query results are re-ranked by question class information.Experiments show that the questions in real-world web data sets can be accurately classified by the classifier,and the QA results after re-ranking can be obviously improved.It is proved that with both semantic and grammatical information,applications such as QA, built upon real-world web data sets, can be improved,thus showing better performance. 展开更多
关键词 question classification question answering real-world web data sets question and answer web forums re-ranking model
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新型城镇化背景下城市地面公交服务质量研究与实践
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作者 秦梦阳 《城市公共交通》 2020年第9期37-41,共5页
本文系统分析了城市地面公交在新型城镇化背景下所暴露出的出行效率上的重视程度不足、与城市发展的适应性滞后、与不同交通方式的衔接性不协调和对人的"移动性"关注不到位的问题。通过对标国内外公共交通的关键性指标、发展... 本文系统分析了城市地面公交在新型城镇化背景下所暴露出的出行效率上的重视程度不足、与城市发展的适应性滞后、与不同交通方式的衔接性不协调和对人的"移动性"关注不到位的问题。通过对标国内外公共交通的关键性指标、发展案例、构建理论及层次体系,提出引导公共交通"系统"发展的评价指标体系。最后,明确指标性质,并以北京市为研究对象,提出近期目标值。 展开更多
关键词 地面公交 “系统”问题 服务质量 指标体系
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ADirect Method for the Problem of the Solid Cylinder in Elasticity 被引量:1
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作者 徐新生 张洪武 钟万勰 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第1期44-54, ,共11页
The traditional semi inverse solution method of the Saint Venant problem and the Saint Venant principle,which were described in the Euclidian space under the Lagrange system formulation,are updated to be solved in the... The traditional semi inverse solution method of the Saint Venant problem and the Saint Venant principle,which were described in the Euclidian space under the Lagrange system formulation,are updated to be solved in the symplectic space under the conservative Hamiltonian system. Thus,the Saint Venant problem and the Saint Venant principle have been unified by the direct method. It is proved in the present paper that all the Saint Venant solutions can be obtained directly via the zero eigenvalue solutions and all their Jordan normal form of the corresponding Hamiltonian operator matrix and the Saint Venant principle corresponds to neglect the non zero eigenvalue solutions,where the non zero eigenvalues give the decay rates. 展开更多
关键词 Hamiltonian system Saint Venant problem Saint Venant principle SYMPLECTIC Eigenvalue problem
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Landscape Changes from 1974 to 1995 in the Upper Minjiang River Basin, China 被引量:16
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作者 HE Xing-Yuan ZHAO Yong-Hua +2 位作者 HU Yuan-Man CHANG Yu ZHOU Qi-Xing 《Pedosphere》 SCIE CAS CSCD 2006年第3期398-405,共8页
Landscape changes were traced over the 20 years from 1974 to 1995 in the upper Minjiang River basin, one of the most important forest regions in China, based on satellite image interpretation to provide basic data for... Landscape changes were traced over the 20 years from 1974 to 1995 in the upper Minjiang River basin, one of the most important forest regions in China, based on satellite image interpretation to provide basic data for local decision-making as well as sustainable landscape use and management. Results revealed that landscape from 1974 to 1995 changed at the regional scale as the area of forestland decreased, while cropland, shrubland, economic forest, grassland, and built-up land increased. Landscape changes mainly occurred in forestland, shrubland, grassland, economic forest, and built-up land. Moreover, the changes among forestland, shrubland, and grassland were the largest, influencing the whole characteristics of the changes in the basin. Analysis of the changes between 1974 and 1995 in the study area indicated that landscape heterogeneity and fragmentation increased, whereas landscape connectivity decreased. There were multiple reasons for landscape changes. A principal component analysis (PCA) was used to quantitatively study driving forces of landscape changes. The PCA results showed that economic and population factors were the principal driving forces of landscape changes from 1974 to 1995 in the upper Minjiang River basin, and that PCA was a suitable method for investigating driving forces of landscape changes. 展开更多
关键词 driving forces landscape change satellite image quantification principal component analysis
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Double Symplectic Eigenfunction Expansion Method of Free Vibration of Rectangular Thin Plates 被引量:7
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作者 WANG Hua Alatancang HUANG Jun-Jie 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第12期1087-1092,共6页
The free vibration problem of rectangular thin plates is rewritten as a new upper triangular matrix differential system. For the associated operator matrix, we find that the two diagonal block operators are Hamiltonia... The free vibration problem of rectangular thin plates is rewritten as a new upper triangular matrix differential system. For the associated operator matrix, we find that the two diagonal block operators are Hamiltonian. Moreover, the existence and completeness of normed symplectic orthogonal eigenfunction systems of these two block operators are demonstrated. Based on the completeness, the general solution of the free vibration of rectangular thin plates is given by double symplectie eigenfunction expansion method. 展开更多
关键词 free vibration of rectangular thin plate double symplectic eigenfunction expansion method upper triangular matrix differential system general solution
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Applying memetic algorithm-based clustering to recommender system with high sparsity problem 被引量:2
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作者 MARUNG Ukrit THEERA-UMPON Nipon AUEPHANWIRIYAKUL Sansanee 《Journal of Central South University》 SCIE EI CAS 2014年第9期3541-3550,共10页
A new recommendation method was presented based on memetic algorithm-based clustering. The proposed method was tested on four highly sparse real-world datasets. Its recommendation performance is evaluated and compared... A new recommendation method was presented based on memetic algorithm-based clustering. The proposed method was tested on four highly sparse real-world datasets. Its recommendation performance is evaluated and compared with that of the frequency-based, user-based, item-based, k-means clustering-based, and genetic algorithm-based methods in terms of precision, recall, and F1 score. The results show that the proposed method yields better performance under the new user cold-start problem when each of new active users selects only one or two items into the basket. The average F1 scores on all four datasets are improved by 225.0%, 61.6%, 54.6%, 49.3%, 28.8%, and 6.3% over the frequency-based, user-based, item-based, k-means clustering-based, and two genetic algorithm-based methods, respectively. 展开更多
关键词 memetic algorithm recommender system sparsity problem cold-start problem clustering method
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Dynamical Correction of Control Laws for Marine Ships’ Accurate Steering 被引量:1
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作者 Evgeny I. Veremey 《Journal of Marine Science and Application》 2014年第2期127-133,共7页
The objective of this work is the analytical synthesis problem for marine vehicles autopilots design. Despite numerous known methods for a solution, the mentioned problem is very complicated due to the presence of an ... The objective of this work is the analytical synthesis problem for marine vehicles autopilots design. Despite numerous known methods for a solution, the mentioned problem is very complicated due to the presence of an extensive population of certain dynamical conditions, requirements and restrictions, which must be satisfied by the appropriate choice of a steering control law. The aim of this paper is to simplify the procedure of the synthesis, providing accurate steering with desirable dynamics of the control system. The approach proposed here is based on the usage of a special unified multipurpose control law structure that allows decoupling a synthesis into simpler particular optimization problems. In particular, this structure includes a dynamical corrector to support the desirable features for the vehicle's motion under the action of sea wave disturbances. As a result, a specialized new method for the corrector design is proposed to provide an accurate steering or a trade-off between accurate steering and economical steering of the ship. This method guaranties a certain flexibility of the control law with respect to an actual environment of the sailing;its corresponding turning can be realized in real time onboard. 展开更多
关键词 marine ships control law dynamical corrector accurate steering autopilot sea wave
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Adaptive Control and Function Projective Synchronization in 2D Discrete-Time Chaotic Systems 被引量:7
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作者 LI Yin CHEN Yong LI Biao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期270-278,共9页
This study addresses the adaptive control and function projective synchronization problems between 2D Rulkov discrete-time system and Network discrete-time system. Based on backstepping design with three controllers, ... This study addresses the adaptive control and function projective synchronization problems between 2D Rulkov discrete-time system and Network discrete-time system. Based on backstepping design with three controllers, a systematic, concrete and automatic scheme is developed to investigate the function projective synchronization of discretetime chaotic systems. In addition, the adaptive control function is applied to achieve the state synchronization of two discrete-time systems. Numerical results demonstrate the effectiveness of the proposed control scheme. 展开更多
关键词 adaptive function projective synchronization backstepping design adaptive control discrete-time chaotic system
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Layer-layout-based heuristics for loading homogeneous items into a single container 被引量:3
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作者 WANG Zhou-jing LI Kevin W 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第12期1944-1952,共9页
The container loading problem (CLP) is a well-known NP-hard problem. Due to the computation complexity, heuristics is an often-sought approach. This article proposes two heuristics to pack homogeneous rectangular boxe... The container loading problem (CLP) is a well-known NP-hard problem. Due to the computation complexity, heuristics is an often-sought approach. This article proposes two heuristics to pack homogeneous rectangular boxes into a single container. Both algorithms adopt the concept of building layers on one face of the container, but the first heuristic determines the layer face once for all, while the second treats the remaining container space as a reduced-sized container after one layer is loaded and, hence, selects the layer face dynamically. To handle the layout design problem at a layer's level, a block-based 2D packing procedure is also developed. Numerical studies demonstrate the efficiency of the heuristics. 展开更多
关键词 Container loading problem (CLP) HEURISTIC LAVER Packing. Optimization
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Design of Anti-Collision Integrated Security Mechanism Based on Chaotic Sequence in UHF RFID System 被引量:5
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作者 YUE Keqiang SUN Lingling +1 位作者 QIN Xing ZHENG Zhonghua 《China Communications》 SCIE CSCD 2014年第3期137-147,共11页
Collision and security issues are considered as barriers to RFID applications.In this paper,a parallelizable anti-collision based on chaotic sequence combined dynamic frame slotted aloha to build a high-efficiency RFI... Collision and security issues are considered as barriers to RFID applications.In this paper,a parallelizable anti-collision based on chaotic sequence combined dynamic frame slotted aloha to build a high-efficiency RFID system is proposed.In the tags parallelizable identification,we design a Discrete Markov process to analyze the success identification rate.Then a mutual authentication security protocol merging chaotic anti-collision is presented.The theoretical analysis and simulation results show that the proposed identification scheme has less than 45.1%of the identification time slots compared with the OVSF-system when the length of the chaos sequence is 31.The success identification rate of the proposed chaotic anti-collision can achieve 63%when the number of the tag is100.We test the energy consumption of the presented authentication protocol,which can simultaneously solve the anti-collision and security of the UHF RFID system. 展开更多
关键词 ANTI-COLLISION SECURITY chaoticsequence discrete Markov process performance analysis
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New Integrable Couplings of Generalized Kaup-Newell Hierarchy and Its Hamiltonian Structures 被引量:3
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作者 夏铁成 张改莲 范恩贵 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第7期1-4,共4页
A new isospectral problem is firstly presented, then we derive integrable system of soliton hierarchy. Also we obtain new integrable couplings of the generalized Kaup-Newell soliton equations hierarchy and its Hamilto... A new isospectral problem is firstly presented, then we derive integrable system of soliton hierarchy. Also we obtain new integrable couplings of the generalized Kaup-Newell soliton equations hierarchy and its Hamiltonian structures by using Tu scheme and the quadratic-form identity. The method can be generalized to other soliton hierarchy. 展开更多
关键词 7the generalized Kaup-Newell hierarchy integrable couplings spectral problem
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Simultaneous optimization of transit network and public bicycle station network 被引量:1
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作者 刘洋 朱宁 马寿峰 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1574-1584,共11页
The traditional manner to design public transportation system is to sequentially design the transit network and public bicycle network. A new public transportation system design problem that simultaneously considers b... The traditional manner to design public transportation system is to sequentially design the transit network and public bicycle network. A new public transportation system design problem that simultaneously considers both bus network design and public bicycle network design is proposed. The chemical reaction optimization(CRO) is designed to solve the problem. A shortcoming of CRO is that, when the two-molecule collisions take place, the molecules are randomly picked from the container.Hence, we improve CRO by employing different mating strategies. The computational results confirm the benefits of the mating strategies. Numerical experiments are conducted on the Sioux-Falls network. A comparison with the traditional sequential modeling framework indicates that the proposed approach has a better performance and is more robust. The practical applicability of the approach is proved by employing a real size network. 展开更多
关键词 public transportation system transit route design bicycle sharing system chemical reaction optimization mating strategy
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Darboux Transformation and New Soliton-like Solutions for (1+1)-Dimensional Higher-Order Broer-Kaup System 被引量:1
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作者 YU Rui HUANG Ding-Jiang ZHANG Hong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期401-404,共4页
In this letter, we construct a kind of new Darboux transformation for the (1+1)-dimensional higher-order Broer-Kaup (HBK) system with the help of a gauge transformation of a spectral problem. By applying this new... In this letter, we construct a kind of new Darboux transformation for the (1+1)-dimensional higher-order Broer-Kaup (HBK) system with the help of a gauge transformation of a spectral problem. By applying this new Darboux transformation, some new soliton-like solutions of the (1+1)-dimensional HBK system are obtained. 展开更多
关键词 Darboux transformation (1+1)-dimensional higher-order Broer-Kaup system soliton-like solu-tions
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A Greedy Algorithm for Task Offloading in Mobile Edge Computing System 被引量:32
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作者 Feng Wei Sixuan Chen Weixia Zou 《China Communications》 SCIE CSCD 2018年第11期149-157,共9页
Mobile edge computing (MEC) is a novel technique that can reduce mobiles' com- putational burden by tasks offioading, which emerges as a promising paradigm to provide computing capabilities in close proximity to mo... Mobile edge computing (MEC) is a novel technique that can reduce mobiles' com- putational burden by tasks offioading, which emerges as a promising paradigm to provide computing capabilities in close proximity to mobile users. In this paper, we will study the scenario where multiple mobiles upload tasks to a MEC server in a sing cell, and allocating the limited server resources and wireless chan- nels between mobiles becomes a challenge. We formulate the optimization problem for the energy saved on mobiles with the tasks being dividable, and utilize a greedy choice to solve the problem. A Select Maximum Saved Energy First (SMSEF) algorithm is proposed to realize the solving process. We examined the saved energy at different number of nodes and channels, and the results show that the proposed scheme can effectively help mobiles to save energy in the MEC system. 展开更多
关键词 mobile edge computing task off- loading greedy choice energy resource allo- cation
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Transceiver Optimization for Multi-Antenna Device-to-Device Communications 被引量:1
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作者 Daohua Zhu Yajuan Guo +4 位作者 Lei Wei Chaoyang Zhu Biyao Huang Wei Xu Chunming Zhao 《China Communications》 SCIE CSCD 2016年第5期110-121,共12页
It has been shown that the deployment of device-to-device(D2D) communication in cellular systems can provide better support for local services. However, improper design of the hybrid system may cause severe interferen... It has been shown that the deployment of device-to-device(D2D) communication in cellular systems can provide better support for local services. However, improper design of the hybrid system may cause severe interference between cellular and D2D links. In this paper, we consider transceiver design for the system employing multiple antennas to mitigate the interference. The precoder and decoder matrices are optimized in terms of sum mean squared error(MSE) and capacity, respectively. For the MSE minimization problem, we present an alternative transceiver optimization algorithm. While for the non-convex capacity maximization problem, we decompose the primal problem into a sequence of standard convex quadratic programs for efficient optimization. The evaluation of our proposed algorithms for performance enhancement of the entire D2D integrated cellular system is carried out through simulations. 展开更多
关键词 device-to-device communication interference mitigation joint transceiver design multiple antennas
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A novel PID controller tuning method based on optimization technique 被引量:5
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作者 梁昔明 李山春 HASSAN A B 《Journal of Central South University》 SCIE EI CAS 2010年第5期1036-1042,共7页
An approach for parameter estimation of proportional-integral-derivative(PID) control system using a new nonlinear programming(NLP) algorithm was proposed.SQP/IIPM algorithm is a sequential quadratic programming(SQP) ... An approach for parameter estimation of proportional-integral-derivative(PID) control system using a new nonlinear programming(NLP) algorithm was proposed.SQP/IIPM algorithm is a sequential quadratic programming(SQP) based algorithm that derives its search directions by solving quadratic programming(QP) subproblems via an infeasible interior point method(IIPM) and evaluates step length adaptively via a simple line search and/or a quadratic search algorithm depending on the termination of the IIPM solver.The task of tuning PI/PID parameters for the first-and second-order systems was modeled as constrained NLP problem. SQP/IIPM algorithm was applied to determining the optimum parameters for the PI/PID control systems.To assess the performance of the proposed method,a Matlab simulation of PID controller tuning was conducted to compare the proposed SQP/IIPM algorithm with the gain and phase margin(GPM) method and Ziegler-Nichols(ZN) method.The results reveal that,for both step and impulse response tests,the PI/PID controller using SQP/IIPM optimization algorithm consistently reduce rise time,settling-time and remarkably lower overshoot compared to GPM and ZN methods,and the proposed method improves the robustness and effectiveness of numerical optimization of PID control systems. 展开更多
关键词 PID controller optimization infeasible interior point method sequential quadratic programming SIMULATION
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Research on Systematic Analysis and Countermeasures of the Buildings Construction Safety Problems 被引量:2
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作者 Shen Liangfeng Li Jie Fan Yeming 《Engineering Sciences》 EI 2008年第1期59-65,共7页
The buildings construction safety problems contain various safety-hidden dangers that caused by the human unsafe behaviors, the substance unsafe conditions, operation environment unsafe factors and management defects.... The buildings construction safety problems contain various safety-hidden dangers that caused by the human unsafe behaviors, the substance unsafe conditions, operation environment unsafe factors and management defects. The authors summarize comprehensively the problems of buildings construetion safety in China at present based on grasping the whole safety status of buildings construction, and the synthetic countermeasures including the systems about laws, management, technology and education civilization for buildings construction safety management are brought up based on the viewpoint of safety system theory. Then it is thought that huilding scientific management mechanisms and popularizing effective management methods and measures are the fundamental ways for improving further the level of safety management for buildings construction in China at present. 展开更多
关键词 building construction safety management PROBLEM COUNTERMEASURES
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