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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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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 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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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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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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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 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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Appropriate Combination of Crossover Operator and Mutation Operator in Genetic Algorithms for the Travelling Salesman Problem
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作者 Zakir Hussain Ahmed Habibollah Haron Abdullah Al-Tameem 《Computers, Materials & Continua》 SCIE EI 2024年第5期2399-2425,共27页
Genetic algorithms(GAs)are very good metaheuristic algorithms that are suitable for solving NP-hard combinatorial optimization problems.AsimpleGAbeginswith a set of solutions represented by a population of chromosomes... Genetic algorithms(GAs)are very good metaheuristic algorithms that are suitable for solving NP-hard combinatorial optimization problems.AsimpleGAbeginswith a set of solutions represented by a population of chromosomes and then uses the idea of survival of the fittest in the selection process to select some fitter chromosomes.It uses a crossover operator to create better offspring chromosomes and thus,converges the population.Also,it uses a mutation operator to explore the unexplored areas by the crossover operator,and thus,diversifies the GA search space.A combination of crossover and mutation operators makes the GA search strong enough to reach the optimal solution.However,appropriate selection and combination of crossover operator and mutation operator can lead to a very good GA for solving an optimization problem.In this present paper,we aim to study the benchmark traveling salesman problem(TSP).We developed several genetic algorithms using seven crossover operators and six mutation operators for the TSP and then compared them to some benchmark TSPLIB instances.The experimental studies show the effectiveness of the combination of a comprehensive sequential constructive crossover operator and insertion mutation operator for the problem.The GA using the comprehensive sequential constructive crossover with insertion mutation could find average solutions whose average percentage of excesses from the best-known solutions are between 0.22 and 14.94 for our experimented problem instances. 展开更多
关键词 Travelling salesman problem genetic algorithms crossover operator mutation operator comprehensive sequential constructive crossover insertion mutation
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A Novel Insertion Solution for the Travelling Salesman Problem
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作者 Emmanuel Oluwatobi Asani Aderemi Elisha Okeyinka +5 位作者 Sunday Adeola Ajagbe Ayodele Ariyo Adebiyi Roseline Oluwaseun Ogundokun Temitope Samson Adekunle Pragasen Mudali Matthew Olusegun Adigun 《Computers, Materials & Continua》 SCIE EI 2024年第4期1581-1597,共17页
The studypresents theHalfMax InsertionHeuristic (HMIH) as a novel approach to solving theTravelling SalesmanProblem (TSP). The goal is to outperform existing techniques such as the Farthest Insertion Heuristic (FIH) a... The studypresents theHalfMax InsertionHeuristic (HMIH) as a novel approach to solving theTravelling SalesmanProblem (TSP). The goal is to outperform existing techniques such as the Farthest Insertion Heuristic (FIH) andNearest Neighbour Heuristic (NNH). The paper discusses the limitations of current construction tour heuristics,focusing particularly on the significant margin of error in FIH. It then proposes HMIH as an alternative thatminimizes the increase in tour distance and includes more nodes. HMIH improves tour quality by starting withan initial tour consisting of a ‘minimum’ polygon and iteratively adding nodes using our novel Half Max routine.The paper thoroughly examines and compares HMIH with FIH and NNH via rigorous testing on standard TSPbenchmarks. The results indicate that HMIH consistently delivers superior performance, particularly with respectto tour cost and computational efficiency. HMIH’s tours were sometimes 16% shorter than those generated by FIHand NNH, showcasing its potential and value as a novel benchmark for TSP solutions. The study used statisticalmethods, including Friedman’s Non-parametric Test, to validate the performance of HMIH over FIH and NNH.This guarantees that the identified advantages are statistically significant and consistent in various situations. Thiscomprehensive analysis emphasizes the reliability and efficiency of the heuristic, making a compelling case for itsuse in solving TSP issues. The research shows that, in general, HMIH fared better than FIH in all cases studied,except for a few instances (pr439, eil51, and eil101) where FIH either performed equally or slightly better thanHMIH. HMIH’s efficiency is shown by its improvements in error percentage (δ) and goodness values (g) comparedto FIH and NNH. In the att48 instance, HMIH had an error rate of 6.3%, whereas FIH had 14.6% and NNH had20.9%, indicating that HMIH was closer to the optimal solution. HMIH consistently showed superior performanceacross many benchmarks, with lower percentage error and higher goodness values, suggesting a closer match tothe optimal tour costs. This study substantially contributes to combinatorial optimization by enhancing currentinsertion algorithms and presenting a more efficient solution for the Travelling Salesman Problem. It also createsnew possibilities for progress in heuristic design and optimization methodologies. 展开更多
关键词 Nearest neighbour heuristic farthest insertion heuristic half max insertion heuristic tour construction travelling salesman problem
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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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Fosmid library construction and screening for the maize mutant gene Vestigial glume 1 被引量:5
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作者 Chaoxian Liu Xiaoli Liu +2 位作者 Lei Lei Haiying Guan Yilin Cai 《The Crop Journal》 SCIE CAS CSCD 2016年第1期55-60,共6页
The maize mutant gene Vestigial glume 1(Vg1) has been fine-mapped to a narrow region by map-based cloning and the candidate gene for Vg1 spanned 19.5 kb. Here we report Vg1 genomic fosmid library construction and scre... The maize mutant gene Vestigial glume 1(Vg1) has been fine-mapped to a narrow region by map-based cloning and the candidate gene for Vg1 spanned 19.5 kb. Here we report Vg1 genomic fosmid library construction and screening. The fosmid library of Vg1 consisted of574,000 clones with an average insert size of 36.4 kb, representing 7.9-fold coverage of the maize genome. Fosmid stability assays indicated that clones were stable during propagation in the fosmid system. Using Vg1 candidate gene-specific primers, a positive clone was successfully identified. This discovery will pave the way for identifying the function of Vg1 in maize development. 展开更多
关键词 VESTIGIAL GLUME 1 FOSMID library construction library SCREENING
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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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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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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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Library Information Resource Allocation: Problems and Countermeasures
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作者 Yanping Dong 《Journal of Contemporary Educational Research》 2019年第2期35-39,共5页
The library is the center of information gathering of a school.The collections present in the library can be regarded as a huge resource of information,consisting of rich knowledge contents from various disciplines.Ho... The library is the center of information gathering of a school.The collections present in the library can be regarded as a huge resource of information,consisting of rich knowledge contents from various disciplines.However,the access to this information is still considered imperfect,where many of these knowledge contents are rarely used or even touched while other resources were often left vacant which has led to many contradictions in the application of information resources in higher learning institution libraries.This article focuses on the analysis of the problems existing in the allocation and management of library information resources,with proposed corresponding solutions. 展开更多
关键词 CONFIGURATION problem COUNTERMEASURE information RESOURCES library
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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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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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