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The Budget Constrained Multi-product Newsboy Problem with Reactive Production:A Problem from Entrepreneurial Network Construction
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作者 LI WEN-JIN PANG YAN-NI 《Communications in Mathematical Research》 CSCD 2012年第2期97-107,共11页
This paper develops an extended newsboy model and presents a formula- tion for this model. This new model has solved the budget contained multi-product newsboy problem with the reactive production. This model can be u... This paper develops an extended newsboy model and presents a formula- tion for this model. This new model has solved the budget contained multi-product newsboy problem with the reactive production. This model can be used to describe the status of entrepreneurial network construction. We use the Lagrange multiplier procedure to deal with our problem, but it is too complicated to get the exact solu-tion. So we introduce the homotopy method to deal with it. We give the flow chart to describe how to get the solution via the homotopy method. We also illustrate our model in both the classical procedure and the homotopy method. Comparing the two methods, we can see that the homotopy method is more exact and efficient. 展开更多
关键词 newsboy problem entrepreneurial network construction multi-product budget constrained reactive production homotopy method
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Study on Problems and Countermeasures of English Hidden Curriculum Construction in Higher Vocational Colleges in the Era of “Internet Plus” 被引量:1
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作者 谢丹 《海外英语》 2017年第7期245-246,共2页
As the extension and supplement of explicit curriculum,the English hidden curriculum in higher vocational colleges plays animportant role in cultivating students' behaviors,stimulate their interest and arouse thei... As the extension and supplement of explicit curriculum,the English hidden curriculum in higher vocational colleges plays animportant role in cultivating students' behaviors,stimulate their interest and arouse their enthusiasm,initiative and creativity in learningEnglish.This paper analyzes the problems of English hidden curriculum construction in higher vocational colleges under the back-ground o"fInternet plus",and puts forward some corresponding countermeasures to bring the role of college English hidden curriculuminto full play. 展开更多
关键词 "Internet plus" higher vocational colleges construction of English hidden curriculum problems and countermeasures
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The Construction Method for Solving Radial Flow Problem through the Homogeneous Reservoir 被引量:5
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作者 Shunchu Li Wei Li +1 位作者 Xiaoping Li Li Xu 《Applied Mathematics》 2012年第6期517-522,共6页
On the basis of similar structure of solutions of ordinary differential equation (ODE) boundary value problem, the similar construction method was put forward by solving problems of fluid flow in porous media through ... On the basis of similar structure of solutions of ordinary differential equation (ODE) boundary value problem, the similar construction method was put forward by solving problems of fluid flow in porous media through the homogeneous reservoir. It is indicate that the pressure distribution of dimensionless reservoir and bottom hole in Laplace space, which take on the radial flow, also shows similar structure, and the internal relationship between the above solutions were illustrated in detail. 展开更多
关键词 Differential Equation Fluid FLOW in Porous Media BOUNDARY Value problem construction Method Similar Structure RADIAL FLOW HOMOGENEOUS RESERVOIR
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A Construction Heuristic for the Split Delivery Vehicle Routing Problem 被引量:6
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作者 Joseph Hubert Wilck IV Tom M. Cavalier 《American Journal of Operations Research》 2012年第2期153-162,共10页
The Split Delivery Vehicle Routing Problem (SDVRP) is a relaxation of the Capacitated Vehicle Routing Problem (CVRP) where customers may be assigned to multiple routes. A new construction heuristic is developed for th... The Split Delivery Vehicle Routing Problem (SDVRP) is a relaxation of the Capacitated Vehicle Routing Problem (CVRP) where customers may be assigned to multiple routes. A new construction heuristic is developed for the SDVRP and computational results are given for thirty-two data sets from previous literature. With respect to the total travel distance, the construction heuristic compares favorably versus a column generation method and a two-phase method. In addition, the construction heuristic is computationally faster than both previous methods. This construction heuristic could be useful in developing initial solutions, very quickly, for a heuristic, algorithm, or exact procedure. 展开更多
关键词 Vehicle ROUTING problem TRANSPORTATION construction HEURISTICS
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Solving the Generalized Traveling Salesman Problem Using Sequential Constructive Crossover Operator in Genetic Algorithm
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作者 Zakir Hussain Ahmed Maha Ata Al-Furhood +1 位作者 Abdul Khader Jilani Saudagar Shakir Khan 《Computer Systems Science & Engineering》 2024年第5期1113-1131,共19页
The generalized travelling salesman problem(GTSP),a generalization of the well-known travelling salesman problem(TSP),is considered for our study.Since the GTSP is NP-hard and very complex,finding exact solutions is h... The generalized travelling salesman problem(GTSP),a generalization of the well-known travelling salesman problem(TSP),is considered for our study.Since the GTSP is NP-hard and very complex,finding exact solutions is highly expensive,we will develop genetic algorithms(GAs)to obtain heuristic solutions to the problem.In GAs,as the crossover is a very important process,the crossovermethods proposed for the traditional TSP could be adapted for the GTSP.The sequential constructive crossover(SCX)and three other operators are adapted to use in GAs to solve the GTSP.The effectiveness of GA using SCX is verified on some GTSP Library(GTSPLIB)instances first and then compared against GAs using the other crossover methods.The computational results show the success of the GA using SCX for this problem.Our proposed GA using SCX,and swap mutation could find average solutions whose average percentage of excesses fromthe best-known solutions is between 0.00 and 14.07 for our investigated instances. 展开更多
关键词 Generalized travelling salesman problem NP-HARD genetic algorithms sequential constructive crossover swap mutation
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Discussion on the Problems and Developing Trend of Construction of Sewage Treatment Plants in Small Towns 被引量:1
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作者 Liu Jiangguo 《Meteorological and Environmental Research》 CAS 2018年第1期53-56,共4页
Existing problems of sewage treatment plants in small towns were summarized firstly,and then the developing trend of construction of sewage treatment plants in small towns was discussed from the aspects of project dec... Existing problems of sewage treatment plants in small towns were summarized firstly,and then the developing trend of construction of sewage treatment plants in small towns was discussed from the aspects of project decision,site selection,design,processing technology and construction financing models. Finally,outlooks for its future development were proposed to provide reference for the construction of sewage treatment plants in small towns in future. 展开更多
关键词 Small towns Sewage treatment plants construction problemS Developing trend
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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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Parallel Construction Heuristic Combined with Constraint Propagation for the Car Sequencing Problem 被引量:1
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作者 Xiangyang ZHANG Liang GAO +1 位作者 Long WEN Zhaodong HUANG 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第2期373-384,共12页
For the car sequencing(CS) problem, the draw-backs of the "sliding windows" technique used in the objective function have not been rectified, and no high quality initial solution has been acquired to accelerate th... For the car sequencing(CS) problem, the draw-backs of the "sliding windows" technique used in the objective function have not been rectified, and no high quality initial solution has been acquired to accelerate the improvement of the solution quality. Firstly, the objective function is improved to solve the double and bias counting of violations broadly discussed. Then, a new method combining heuristic with constraint propagation is proposed which constructs initial solutions under a parallel framework. Based on constraint propagation, three filtering rules are designed to intersecting with three greedy functions, so the variable domain is narrowed in the process of the construction. The parallel framework is served to show its robustness in terms of the quality of the solution since it greatly increases the performance of obtaining the best solution. In the computational experiments, 109 instances of 3 sets from the CSPLib' s benchmarks are used to test the performance of the proposed method. Experiment results show that the proposed method outperforms others in acquiring the best-known results for 85 best-known results of 109 are obtained with only one construction. The proposed research provides an avenue to remedy the deficiencies of "sliding windows" technique and construct high quality initial solutions. 展开更多
关键词 Car sequencing problem · Constraint propagation · Parallel construction heuristic · Filtering rule
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Countermeasures for Solving the Environmental Problems and Accelerating the Model City Construction of Xi'an
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作者 Liu Zhenxiang Song Ting Ma Longbao 《Meteorological and Environmental Research》 CAS 2014年第2期55-58,62,共5页
Through careful study, it found that the key and difficult points of affecting and restricting Xi'an to reach the model city construction standards in provincial and national levels were "urban air environment quali... Through careful study, it found that the key and difficult points of affecting and restricting Xi'an to reach the model city construction standards in provincial and national levels were "urban air environment quality standards" and "water qualification rate of urban water environment function area". In order to tackle with the weak links, highlight the important points and focus on the difficult points to strengthen scientific and technological innovation, we actively explored new ideas and ways to resolve the dilemma in meeting the two standards of model city construction, and we managed to put forward the countermeasures to resolve the dilemma through innovating system and mechanism. "Place master system" should be carded out quickly to meet the "urban air environment quality standards", while "river master system" should be implemented as soon as possible to reach the "water qualification rate of urban water environment function area". The aim of this study was to enhance the qualification rates of the indicators for model city construction to make Xi'an successfully pass the provincial and national assessment of model city construction through dealing with the weak links to accelerate the realization of becoming model environmental protection city. 展开更多
关键词 Model environmental protection city construction COUNTERMEASURES Environmental problems China
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Current Situations and Problems of Investment in Agricultural Capital Construction from the Perspective of Investment of Different Ministries and Commissions and Recommendations
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作者 Lin ZHAI Jiliang MA 《Asian Agricultural Research》 2018年第5期1-6,9,共7页
Investment in agricultural capital construction is an important factor in improving China's agricultural productivity and international competitiveness. In recent years,the attention to the investment in agricultu... Investment in agricultural capital construction is an important factor in improving China's agricultural productivity and international competitiveness. In recent years,the attention to the investment in agricultural capital construction has been lifted to a strategic height. However,there is still little research on the investment in agricultural capital construction. From the perspective of investment of different ministries and commissions,this paper systematically analyzed current situations,problems,and came up with recommendations for the investment in the agricultural capital construction. According to the results,( i) from 1983 to the present,China's investment in agricultural capital construction experienced three stages. Especially after 2010,the scale of investment in agricultural capital construction was huge,and it showed a rapid increasing trend;( ii) the investment in agricultural capital construction is characterized by " multi-sector investment,different departments having different investment priorities and investment scale in different periods";( iii) some investment projects are overlapping between departments,local areas are weak in providing support funds,project construction standard is single,and there are problems of attaching importance to the application,belittling the management,stressing the construction,belittling the maintenance,and serious brain drain;( iv) different departments have accumulated certain experience in long-term exploration. For example,they pay more attention to the refinement and differentiation of projects,focus on the development of targeted poverty alleviation,pay more attention to the " quality" of investment,and pay more attention to the transformation of agricultural production methods. Based on current situations and problems,it came up with recommendations including promoting the integration of funds for investment and project integration,strengthening the personnel cultivation,ensuring simultaneous construction and management of projects,stressing the maintenance after project construction,exploring new modes for project design,management,investment,and financing,and enhancing the support for special investment projects. 展开更多
关键词 Investment in agricultural capital construction Current situations problemS RECOMMENDATIONS
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A Preliminary Analysis of the Tomography Problems in Constructing Bridge and Dike-Road across Taiwan Strait
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作者 GUO Lu-can PENG Fuman 《CT理论与应用研究(中英文)》 2004年第3期61-63,共3页
The construction of the bridge across Taiwan Strait has been studied for a long time and the feasibility study that has attracted attention among scientists and engineers on both sides of the Taiwan Strait[1-4].The ke... The construction of the bridge across Taiwan Strait has been studied for a long time and the feasibility study that has attracted attention among scientists and engineers on both sides of the Taiwan Strait[1-4].The key question is whether this bridge and dike-road across Taiwan Strait can be constructed with present technology under such complex geological conditions or not.The results of current researches indicate that the sea floor of the Strait is covered with a horizontal layer composed of both the Pleistocene and the Holocene sandstone and shale with a thickness of about 200~300m.The distance from Pingtan island to China's Xinzhu seashore is 124 km,which might be connected by 4-6 section bridges and 5-7 section of dike-roads,and serve as a best program of the route in the north Strait section.The NE offshore fault along the Fujian coast and that along the west coast of Taiwan,China are the major tectonic lines separated by several NW faults under the upper horizontal layer,these fault 3D feature may be detecting by geo-tomography technique,which can help to deal with the foundation of bridge and dike-road piers.It is judged that the construction of bridge and dike-road beginning from Pingtan to the China's Xinzhu seashore is worth recommendation.In the procedure of the construction of large and high height bridges,must consider the steel structural member be detected by industrial CT technology,and might detect the pier of bridge and dike-road which built by steel tube and reinforced concrete at dike-roads two side,in order to get the hard basement and getting the depth of the pier extend below the sea-floor by the seismic tomographic detection method. 展开更多
关键词 Taiwan Strait tomography problem Pingtan Island constructing bridge dike-road
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On the Construction of Deepening Anti - corruption Mechanism
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作者 Ding Huanxiang Xuliang 《学术界》 CSSCI 北大核心 2018年第3期260-272,共13页
It needs the foundation of system and the guarantee of organizational system for anti-corruption,but it is more necessary to build and form an effective anti-corruption mechanism,so that the anti-corruption can be rea... It needs the foundation of system and the guarantee of organizational system for anti-corruption,but it is more necessary to build and form an effective anti-corruption mechanism,so that the anti-corruption can be really put into practice. Anti-corruption mechanism refers to a organic operation system of the interaction,interconnection and constraint between the constituent elements( parts) and elements of national anti-corruption,and as a system,anti-corruption mechanism should have the characteristics of system aticness,comprehensiveness,transparency,legalization,public participation,scientific dynam ic,and internationalism. The construction of deepening anti-corruption mechanism is the need for reconstructing the ruling legitimacy of the party and the governm ent. Adhering to the principle of treating both root causes and symptoms is necessary in the construction of anti-corruption m echanism,com bating and punishing corruption is an important part of anti-corruption,and the prevention and control of corruption is the basic project of anti-corruption. Therefore,the construction of prevention and control mechanism in the anti-corruption mechanism has a more far-reaching significance. 展开更多
关键词 anti - CORRUPTION MECHANISM construction CONNOTATION and definition val-ue analysis prevention and control MECHANISM
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Construction of Legal System of China's Farmland Protection under the Coexistence of Multiple Objectives:Historical Logic,Practical Problems and Optimization Paths
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作者 Shengnan MA Jiaxin ZHOU Yongfang YANG 《Asian Agricultural Research》 2023年第2期26-34,38,共10页
[Objectives]To explore the evolution of the legal system of farmland protection and explore the rules and characteristics of policy development based on the theory and logic of institutional change since China's r... [Objectives]To explore the evolution of the legal system of farmland protection and explore the rules and characteristics of policy development based on the theory and logic of institutional change since China's reform and opening up,reveal the problems and deep-seated reasons of its legislation,clarify the direction of farmland protection in the new period,and solve the"non-agricultural""non-grain"and ecological problems of farmland.[Methods]Literature analysis and inductive deduction methods were used.[Results]The evolution of the farmland protection legal system has gone through the process of"national consciousness-policy guidelines-institutional system",the change from"single subject to multiple subjects";change from the use of"one-way administrative means to coordinated use of administrative,economic and technical means".The practical problems of the farmland protection legal system are mainly due to the insufficient systematization of the farmland protection legal system itself,the generalization of quantity protection,the transformation of quality protection,and the absence of ecological protection.[Conclusions]It is recommended to improve the existing farmland protection legal system from the establishment of the Farmland Protection Law,the improvement of the farmland protection public participation mechanism and supervision mechanism,the establishment of the farmland quality construction and improvement system,the differentiated farmland occupation and supplementation balance system,and the ecological restoration system. 展开更多
关键词 Farmland protection Legal system construction Policy evolution Existing problems Optimization path
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Analysis of Urban Road Construction and Related Problems and Countermeasures
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作者 Zhiqiang Ye 《Frontiers Research of Architecture and Engineering》 2019年第1期24-27,共4页
With the rapid development of China’s economy,China’s urbanization process is also accelerating,the municipal road as an important supporting force to accelerate the construction of urbanization is becoming more and... With the rapid development of China’s economy,China’s urbanization process is also accelerating,the municipal road as an important supporting force to accelerate the construction of urbanization is becoming more and more important,corresponding,the city’s requirements on the road is also gradually improving,the quality of the city road affects the daily travel of urban residents.If the road design is not reasonable or the construction quality is not up to standard,it will bring great changes to the urban residents.Therefore,urban road construction will face greater challenges in the future.This paper emphasizes the importance of road construction quality,analyzes some common problems in urban road construction,and puts forward some solutions to the problems in urban road construction. 展开更多
关键词 ROAD construction RELATED problemS COUNTERMEASURES
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Analysis of Common Problems and Technical Points in Quality Management of City Water Supply and Drainage Construction Quality
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作者 Miao Zhaojing Xu Zhaolong 《Journal of Architectural Research and Development》 2018年第4期31-34,共4页
In recent years,the quality of people’s lifestyle has significantly increased when the speed of social and economic development is accelerating.Among them,the management of city water supply and drainage construction... In recent years,the quality of people’s lifestyle has significantly increased when the speed of social and economic development is accelerating.Among them,the management of city water supply and drainage construction quality can provide the necessary guarantee for the improvement of people’s quality of life,so the scientific of construction quality management will also become the focus of urban modernization.However,there are many problems in the management of water supply and drainage construction quality in cities after considering the real situation.If the problems are not solved as soon as possible,it will affect people’s daily life and works badly and also restrict the development of urbanization.Therefore,the implementation and practical of city water supply and drainage construction quality management are very important.Based on this,the main research content of this article is about the city water supply and drainage construction quality management and to elaborate the existed common problems and raises up some technical points and hopes that this article content can help in the management of drainage construction quality. 展开更多
关键词 MUNICIPAL drainage construction QUALITY management COMMON problems technical POINTS
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Discussion on the Construction of Anti-smoke Construction Technology in Super High-rise Buildings
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作者 Xiaolong Ruan 《Journal of World Architecture》 2019年第4期1-4,共4页
In recent years with the increasing number of super high-rise buildings and the ever-expanding scale the anti-smoke construction technology has attracted more and more attention.Based on this situation,this paper anal... In recent years with the increasing number of super high-rise buildings and the ever-expanding scale the anti-smoke construction technology has attracted more and more attention.Based on this situation,this paper analyzes the smoke control technology of super high-rise buildings.The paper analyzes the importance of the application of anti-smoke construction technology in super high-rise buildings,analyzes the problems in the construction of smoke control and super high-rise buildings.The anti-smoke construction technology was studied and I hope that it can benefit the application of anti-smoke construction technology in high-rise buildings. 展开更多
关键词 Super HIGH-RISE BUILDING SMOKE control construction technology problem and optimization
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Quality Problems and Countermeasures in Construction Process
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作者 Chao Xu Guoping Chen Honghui Hua 《Journal of Architectural Environment & Structural Engineering Research》 2020年第1期24-27,共4页
Quality is the life of architecture.Without quality there is nothing.Engineering projects have the characteristics of large investment and long construction period,so the quality of construction projects must be stric... Quality is the life of architecture.Without quality there is nothing.Engineering projects have the characteristics of large investment and long construction period,so the quality of construction projects must be strictly controlled.The control of construction quality of engineering projects is the quality control of the whole process and the participation of all employees.It is the implementation of construction engineering quality regulations and mandatory standards,the correct configuration of construction production management elements and the use of scientific management methods to achieve the expected use function of engineering projects And quality standards,deliver the owner a satisfactory quality project.Most of the quality problems of construction projects appear in the construction stage.Therefore,we must strictly control the quality in project construction,strengthen the whole process management from the organization and management,find a project quality management system suitable for China’s national conditions,and be able to eliminate the hidden quality hazards in the project in time to ensure the project The construction project can meet the target requirements,and the project quality can be effectively controlled.This article mainly analyzes the current problems affecting the construction quality,combined with the actual analysis,and then find some countermeasures to solve the problem. 展开更多
关键词 construction engineering Quality management problemS COUNTERMEASURES
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Equipment delivery and quality problems affectingcompletion of 1997 Power Construction Plan
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《Electricity》 1998年第2期43-44,共2页
关键词 Equipment delivery and quality problems affecting completion of 1997 Power construction Plan
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Analysis of Existing Problems with Management of Construction Projects Bidding and Solutions to the Problems
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作者 Meili Wu 《Journal of Architectural Research and Development》 2021年第2期30-33,共4页
Bidding is a key link during the implementation of a construction project.For the same construction project,there are usually multiple construction companies bidding together to obtain the right to contract for the pr... Bidding is a key link during the implementation of a construction project.For the same construction project,there are usually multiple construction companies bidding together to obtain the right to contract for the project.However,there are still various irregularities in the bidding stage.This article analyzed the above problems and proposed a management strategy for the optimization of bidding,looking forward to improving the quality of bidding management of construction projects,solving various illegal bidding problems,and purifying the environment of bidding management. 展开更多
关键词 construction engineering Bidding management problemS SOLUTIONS
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Analysis of Several Problems in the Construction of Sponge City
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作者 Wei Li 《Journal of World Architecture》 2022年第1期5-9,共5页
Sponge city refers to a new urban construction concept used to solve urban flood disasters and water ecological problems.It is important for the construction of ecological civilization.It plays an important role in th... Sponge city refers to a new urban construction concept used to solve urban flood disasters and water ecological problems.It is important for the construction of ecological civilization.It plays an important role in the green development and livability of the city.In the construction of a sponge city,it is necessary to make special urban planning and improve the top-level design.In recent years,China has developed a number of sponge city pilot projects.The numerous experiments act as important references for the urban construction in China.This paper mainly analyzes the requirements for the construction of sponge city and discusses several problems as well as solutions in the construction. 展开更多
关键词 Sponge city construction problems Solution strategies
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