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Time consumption, productivity, and cost analysis of the motor manual tree felling and processing in the Hyrcanian Forest in Iran
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作者 Rostam Mousavi Mehrdad Nikouy Jori Uusitalo 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第4期665-669,共5页
An empirical time study was cohducted to evaluate the performance of the current felling and tree processing methods used in Northern Iran's Hyrcanian forest. Motor-manual felling is done mostly in winter, while tree... An empirical time study was cohducted to evaluate the performance of the current felling and tree processing methods used in Northern Iran's Hyrcanian forest. Motor-manual felling is done mostly in winter, while tree processing starts when the felling season ends. We identified the elements of felling and processing work phases, and 142 cycles and 110 cycles were respectively recorded for felling and processing. On the basis of data analysis (time study), we developed statistical models of effective time consumption in the respective work phase and for its total productivity. The production rate of felling with and without delay time was 9.7 and 11.65 trees per hour (0.17 USD.m^-3 and 0.21 USD-m^-3), and the average production cost with and without delay was 1.21 USD and 1.45 USD per tree, respectively. The average productivity of processing was 35 m^3 per effective hour and the average unit cost of processing was 0.92 USD.m^-3. 展开更多
关键词 Motor-manual felling time study CHAINSAW processing cost forest work study
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Life cycle inventory for base metal ingots production in Japan including mining and mineral processing processes by cost estimating system database 被引量:1
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作者 T.ADACHI G.MOGI 《中国有色金属学会会刊:英文版》 CSCD 2007年第A01期131-135,共5页
CO2 emission levels of copper and zinc mines from which Japanese smelters import ore concentrates into Japan,were estimated by using a database called MLED. Eleven copper mines selected from data availability of mine ... CO2 emission levels of copper and zinc mines from which Japanese smelters import ore concentrates into Japan,were estimated by using a database called MLED. Eleven copper mines selected from data availability of mine site covered 84% of the total imported concentrates. Adding inventories of sea transportation and smelting processes to mine development process,total CO2 emission level for copper and zinc ingots produced in Japan were calculated. The results show that the emission share of mining and mineral processing processes for each mine is indicated around 30%-70% of total emission for ingots,which implies the importance of including the mining activities to the inventory of upper stream products. 展开更多
关键词 金属材料 铸造方法 矿物 二氧化碳
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SINGLE MACHINE SCHEDULING WITH CONTROLLABLE PROCESSING TIMES AND COMPRESSION COSTS (PART I:EQUAL TIMES AND COSTS) 被引量:1
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作者 TANGGUOCHUN FOULDS,L.R. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1998年第4期417-426,共10页
Abstract Most papers in scheduling research have treated individual job processing times as fixed parameters. However, in many practical situations, a manager may control processing time by reallocating resources. In ... Abstract Most papers in scheduling research have treated individual job processing times as fixed parameters. However, in many practical situations, a manager may control processing time by reallocating resources. In this paper, authors consider a machine scheduling problem with controllable processing times. In the first part of this paper, a special case where the processing times and compression costs are uniform among jobs is discussed. Theoretical results are derived that aid in developing an O(n 2) algorithm to slove the problem optimally. In the second part of this paper, authors generalize the discussion to general case. An effective heuristic to the general problem will be presented. 展开更多
关键词 Machine scheduling problems controllable processing times uniform compression timeand cost dominance set lateness crash activities polynomial time algorithm
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SINGLE MACHINE SCHEDULING WITH CONTROLLABLE PROCESSING TIMES AND COMPRESSION COSTS : PROOF OF THEOREMS
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作者 TANGGUOCHUN FOULDS,L.R. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1998年第4期427-436,共10页
Abstract This report is virtually the appendix part of the author's previous paper which includes the proofs for the theorems and lemmas.
关键词 Machine scheduling problems controllable processing times uniform compression time and cost dominance set lateness crash activities polynomial time algorithm
全文增补中
An LMI Method to Robust Iterative Learning Fault-tolerant Guaranteed Cost Control for Batch Processes 被引量:11
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作者 王立敏 陈曦 高福荣 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期401-411,共11页
Based on an equivalent two-dimensional Fornasini-Marchsini model for a batch process in industry, a closed-loop robust iterative learning fault-tolerant guaranteed cost control scheme is proposed for batch processes w... Based on an equivalent two-dimensional Fornasini-Marchsini model for a batch process in industry, a closed-loop robust iterative learning fault-tolerant guaranteed cost control scheme is proposed for batch processes with actuator failures. This paper introduces relevant concepts of the fault-tolerant guaranteed cost control and formulates the robust iterative learning reliable guaranteed cost controller (ILRGCC). A significant advantage is that the proposed ILRGCC design method can be used for on-line optimization against batch-to-batch process uncertainties to realize robust tracking of set-point trajectory in time and batch-to-batch sequences. For the convenience of implementation, only measured output errors of current and previous cycles are used to design a synthetic controller for iterative learning control, consisting of dynamic output feedback plus feed-forward control. The proposed controller can not only guarantee the closed-loop convergency along time and cycle sequences but also satisfy the H∞performance level and a cost function with upper bounds for all admissible uncertainties and any actuator failures. Sufficient conditions for the controller solution are derived in terms of linear matrix inequalities (LMIs), and design procedures, which formulate a convex optimization problem with LMI constraints, are presented. An example of injection molding is given to illustrate the effectiveness and advantages of the ILRGCC design approach. 展开更多
关键词 two-dimensional Fornasini-Marchsini model batch process iterative learning control linear matrix inequality fault-tolerant guaranteed cost control
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Sequential quadratic programming-based non-cooperative target distributed hybrid processing optimization method 被引量:3
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作者 SONG Xiaocheng WANG Jiangtao +3 位作者 WANG Jun SUN Liang FENG Yanghe LI Zhi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期129-140,共12页
The distributed hybrid processing optimization problem of non-cooperative targets is an important research direction for future networked air-defense and anti-missile firepower systems. In this paper, the air-defense ... The distributed hybrid processing optimization problem of non-cooperative targets is an important research direction for future networked air-defense and anti-missile firepower systems. In this paper, the air-defense anti-missile targets defense problem is abstracted as a nonconvex constrained combinatorial optimization problem with the optimization objective of maximizing the degree of contribution of the processing scheme to non-cooperative targets, and the constraints mainly consider geographical conditions and anti-missile equipment resources. The grid discretization concept is used to partition the defense area into network nodes, and the overall defense strategy scheme is described as a nonlinear programming problem to solve the minimum defense cost within the maximum defense capability of the defense system network. In the solution of the minimum defense cost problem, the processing scheme, equipment coverage capability, constraints and node cost requirements are characterized, then a nonlinear mathematical model of the non-cooperative target distributed hybrid processing optimization problem is established, and a local optimal solution based on the sequential quadratic programming algorithm is constructed, and the optimal firepower processing scheme is given by using the sequential quadratic programming method containing non-convex quadratic equations and inequality constraints. Finally, the effectiveness of the proposed method is verified by simulation examples. 展开更多
关键词 non-cooperative target distributed hybrid processing multiple constraint minimum defense cost sequential quadratic programming
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Research on Optimal Delivery Days and Customer Satisfaction Based on Quality Costs 被引量:3
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作者 薛伟 周宏彤 陈亚绒 《Journal of China University of Mining and Technology》 2004年第1期82-85,共4页
Customer satisfaction is an important index to evaluate the competitiveness and efficiency of an enterprise. Every enterprise is confront with the subject of supplying with the customer satisfactory products at the lo... Customer satisfaction is an important index to evaluate the competitiveness and efficiency of an enterprise. Every enterprise is confront with the subject of supplying with the customer satisfactory products at the lowest costs and the highest manufacturing speed. Regarding the delivery days of a coach company as a design variable, this paper builds up an optimization model of customer satisfaction, and suggests an effective method to reduce costs and increase customer satisfaction based on analysis and research. 展开更多
关键词 quality costs customer satisfaction delivery days optimization design
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VPLS Based Quality and Cost Control for Tennessee Eastman Process 被引量:1
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作者 宋凯 王海清 李平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第1期62-67,共6页
Product quality and operation cost control obtain increasing emphases in modern chemical system engineering. To improve the fault detection power of the partial least square (PLS) method for quality control, a new QRP... Product quality and operation cost control obtain increasing emphases in modern chemical system engineering. To improve the fault detection power of the partial least square (PLS) method for quality control, a new QRPV statistic is proposed in terms of the VP (variable importance in projection) indices of monitored process variables, which is significantly advanced over and different from the conventional Q statistic. QRPV is calculated only by the residuals of the remarkable process variables (RPVs). Therefore, it is the dominant relation between quality and RPV not all process variables (as in the case of the conventional PLS) that is monitored by this new VP-PLS (VPLS) method. The combination of QRPV and T2 statistics is applied to the quality and cost control of the Tennessee Eastman (TE) process, and weak faults can be detected as quickly as possible. Consequently, the product quality of TE process is guaranteed and operation costs are reduced. 展开更多
关键词 partial least squares method Tennessee Eastman process statistical quality control cost control on-line monitoring
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Stability Estimation for Markov Control Processes with Discounted Cost 被引量:1
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作者 Jaime Eduardo Martínez-Sánchez 《Applied Mathematics》 2020年第6期491-509,共19页
This article explores controllable Borel spaces, stationary, homogeneous Markov processes, discrete time with infinite horizon, with bounded cost functions and using the expected total discounted cost criterion. The p... This article explores controllable Borel spaces, stationary, homogeneous Markov processes, discrete time with infinite horizon, with bounded cost functions and using the expected total discounted cost criterion. The problem of the estimation of stability for this type of process is set. The central objective is to obtain a bounded stability index expressed in terms of the Lévy-Prokhorov metric;likewise, sufficient conditions are provided for the existence of such inequalities. 展开更多
关键词 Discrete-Time Markov Control process Expected Total Discounted cost Stability Index Probabilistic Metric Lévy-Prokhorov Metric
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Cost Optimization of Surface Grinding Process 被引量:1
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作者 Vu Ngoc Pi Luu Anh Tung +1 位作者 Le Xuan Hung Banh Tien Long 《Journal of Environmental Science and Engineering(A)》 2016年第12期606-611,共6页
This paper introduces a new study on cost optimization of surface grinding. In the study, the effects of grinding parameters including the dressing regime parameters, the wheel life and the initial grinding wheel diam... This paper introduces a new study on cost optimization of surface grinding. In the study, the effects of grinding parameters including the dressing regime parameters, the wheel life and the initial grinding wheel diameter on the exchanged grinding wheel diameter which were investigated. In addition, the influence of cost parameters including the machine tool hourly rate and the grinding wheel cost were taken into account. In order to find the optimum exchanged grinding wheel diameter, a cost optimization problem was built. From the results of the optimization problem, a model for determination of the optimum exchanged grinding wheel diameter was found. By using the optimum diameter, both the grinding cost and grinding time can be reduced significantly. 展开更多
关键词 GRINDING grinding process surface grinding cost optimization.
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Guaranteed Cost Iterative Learning Control for Multi-Phase Batch Processes
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作者 WANG Limin WANG Runze +4 位作者 XIONG Yuting WANG Haosen ZHU Lin ZHANG Ke GAO Furong 《Journal of Shanghai Jiaotong university(Science)》 EI 2018年第6期811-819,共9页
Batch process is a typical multi-phase process. Due to the interaction between the phases of the batch process, high precision control in a single phase cannot guarantee high precision control of the whole batch proce... Batch process is a typical multi-phase process. Due to the interaction between the phases of the batch process, high precision control in a single phase cannot guarantee high precision control of the whole batch process. In order to solve this problem, the guaranteed cost iterative learning control(ILC) of multi-phase batch processes is studied in this paper. Firstly, through introducing the output error, the state error and the extended information, the multi-phase batch process is transformed into an equivalent 2D switched system which has different dimensions. In addition, under the measurable condition, the guaranteed cost iterative learning control law with extended information is designed. The proposed control law ensures not only the stability of the system but also the optimal control performance. Next, in order to study the stability of the system and the minimum running time under the condition of stable running, the multi-Lyapunov function method is used. By means of the average dwell time method, the sufficient conditions ensuring system to be exponentially stable are given in the form of linear matrix inequality(LMI). Finally, the injection molding process is taken as an example to make simulation, which shows the feasibility and effectiveness of the proposed method. 展开更多
关键词 MULTI-PHASE BATCH process iterative learning control (ILC) AVERAGE DWELL time hybrid guaranteed cost controller
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Process Modeling of Ferrofluids Flow for Magnetic Targeting Drug Delivery
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作者 LIU Handan WANG Shigang XU Wei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第3期440-445,共6页
Among the proposed techniques for delivering drugs to specific sites within the human body, magnetic targeting drug delivery surpasses due to its non-invasive character and its high targeting efficiency. Although ther... Among the proposed techniques for delivering drugs to specific sites within the human body, magnetic targeting drug delivery surpasses due to its non-invasive character and its high targeting efficiency. Although there have been some analyses theoretically for magnetic drug targeting, very few researchers have addressed the hydrodynamic models of magnetic fluids in the blood vessel of human body. This paper presents a mathematical model to describe the hydrodynamics of ferrofluids as drug carriers flowing in a blood vessel under the applied magnetic field. A 3D flow field of magnetic particles in a blood vessel model is numerically simulated in order to further understand clinical application of magnetic targeting drug delivery. Simulation results show that magnetic nanoparticles can be enriched in a target region depending on the applied magnetic field intensity. Magnetic resonance imaging confirms the enrichment of ferrofluids in a desired body tissue of Sprague-Dawley rats. The simulation results coincide with those animal experiments. Results of the analysis provide the important information and can suggest strategies for improving delivery in favor of the clinical application. 展开更多
关键词 Magnetic targeting drug delivery FERROFLUIDS magnetic nano-particels process modeling HYDRODYNAMICS computational fluid dynamics(CFD) numerical simulation Magnetic resonance imaging
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Optimal proportioning of iron ore in sintering process based on improved multi-objective beluga whale optimisation algorithm 被引量:1
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作者 Zong-ping Li Xu-dong Li +5 位作者 Xue-tong Yan Wu Wen Xiao-xin Zeng Rong-jia Zhu Ya-hui Wang Ling-zhi Yi 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2024年第7期1597-1609,共13页
Proportioning is an important part of sintering,as it affects the cost of sintering and the quality of sintered ore.To address the problems posed by the complex raw material information and numerous constraints in the... Proportioning is an important part of sintering,as it affects the cost of sintering and the quality of sintered ore.To address the problems posed by the complex raw material information and numerous constraints in the sintering process,a multi-objective optimisation model for sintering proportioning was established,which takes the proportioning cost and TFe as the optimisation objectives.Additionally,an improved multi-objective beluga whale optimisation(IMOBWO)algorithm was proposed to solve the nonlinear,multi-constrained multi-objective optimisation problems.The algorithm uses the con-strained non-dominance criterion to deal with the constraint problem in the model.Moreover,the algorithm employs an opposite learning strategy and a population guidance mechanism based on angular competition and two-population competition strategy to enhance convergence and population diversity.The actual proportioning of a steel plant indicates that the IMOBWO algorithm applied to the ore proportioning process has good convergence and obtains the uniformly distributed Pareto front.Meanwhile,compared with the actual proportioning scheme,the proportioning cost is reduced by 4.3361¥/t,and the TFe content in the mixture is increased by 0.0367%in the optimal compromise solution.Therefore,the proposed method effectively balances the cost and total iron,facilitating the comprehensive utilisation of sintered iron ore resources while ensuring quality assurance. 展开更多
关键词 Sintering process Proportioning Iron ore Multi-objective beluga whale optimisation algorithm Proportioning cost
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Adaptive Strategies for Accelerating the Convergence of Average Cost Markov Decision Processes Using a Moving Average Digital Filter
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作者 Edilson F. Arruda Fabrício Ourique 《American Journal of Operations Research》 2013年第6期514-520,共7页
This paper proposes a technique to accelerate the convergence of the value iteration algorithm applied to discrete average cost Markov decision processes. An adaptive partial information value iteration algorithm is p... This paper proposes a technique to accelerate the convergence of the value iteration algorithm applied to discrete average cost Markov decision processes. An adaptive partial information value iteration algorithm is proposed that updates an increasingly accurate approximate version of the original problem with a view to saving computations at the early iterations, when one is typically far from the optimal solution. The proposed algorithm is compared to classical value iteration for a broad set of adaptive parameters and the results suggest that significant computational savings can be obtained, while also ensuring a robust performance with respect to the parameters. 展开更多
关键词 AVERAGE cost MARKOV DECISION processes Value ITERATION Computational EFFORT GRADIENT
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The Cost Control of Motor Housing Process
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作者 XU Run 《International Journal of Plant Engineering and Management》 2019年第3期187-192,共6页
As for the assembly line of cost control of Toyota company in, the motor housing also needs cost control. Because the supply quantity of small motor is very large every month, the production line is needed to solve th... As for the assembly line of cost control of Toyota company in, the motor housing also needs cost control. Because the supply quantity of small motor is very large every month, the production line is needed to solve this problem. In addition to the control of equipment, personnel quantities and wages, the introduction of raw materials also needs to be controlled. Only in this way can we fundamentally solve the problem of high cost and low profit. 展开更多
关键词 MOTOR HOUSING process cost CONTROL MOTOR STAMPING equipment
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Research on the Whole Process Cost Management of Government Investment Projects
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作者 WANGZipeng 《外文科技期刊数据库(文摘版)经济管理》 2022年第6期148-151,共4页
The former scientific application of the whole-process cost control management model in government-invested projects is beneficial to scientific response to the problems existing in cost control and engineering constr... The former scientific application of the whole-process cost control management model in government-invested projects is beneficial to scientific response to the problems existing in cost control and engineering construction and to the protection of the legitimate rights and interests of both parties to the contract. Due to the short application time of this model, there are still many links to be improved in practice. Based on the actual situation, this paper analyzes and studies the whole-process cost management model of government-invested projects, explores the causes of the problems, finds out effective measures, gradually adjusts and solves the problems, optimizes the cost management model, and then realizes the rational allocation of resources. Next, the article discusses the whole process cost management of government investment projects. 展开更多
关键词 government investment investment projects whole process cost cost management
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Application of Whole Process Cost Control in Construction Cost Management
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作者 XIAO Han 《外文科技期刊数据库(文摘版)工程技术》 2021年第5期444-446,共5页
The whole process management of project cost is a new management technology, which helps to improve the management effect of the whole project. In the process of engineering, using the whole process cost method can ef... The whole process management of project cost is a new management technology, which helps to improve the management effect of the whole project. In the process of engineering, using the whole process cost method can effectively control the project cost, and then achieve the comprehensive control and management of the project, so as to better improve the development pace and market competitiveness of enterprises. However, because there are many influencing factors in the construction of related construction projects in our country, in order to really do a good job in the whole process of cost management, it is necessary to do a good job in the analysis and control of each link in the actual process of the project, so as to improve the control effect of the project cost, enhance the development competitiveness of enterprises and help enterprises to be better and more sustainable development in the fierce market economy. 展开更多
关键词 whole process cost architectural engineering cost management
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Analysis on Current Situation of Project Cost Management and Whole Process Cost Management
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作者 WANG Meina 《外文科技期刊数据库(文摘版)工程技术》 2021年第11期809-812,共6页
In the process of engineering construction, the expected cost of the project or the actual cost for engineering construction is usually expressed by the engineering cost. There are many factors that affect the project... In the process of engineering construction, the expected cost of the project or the actual cost for engineering construction is usually expressed by the engineering cost. There are many factors that affect the project cost, such as the formulation of national policies, the fluctuation of material labor price, the local geographical environment of the project, etc., which are complex and run through all stages of the construction process and have great impact. In the actual operation of most construction projects in our country, the phenomena such as the final completion settlement investment exceeding the construction drawing budget, the construction budget exceeding the preliminary design budget, and the preliminary design budget exceeding the feasibility study estimate often occur. The reason is that there is no reasonable and scientific cost management in stages. Therefore, on the premise of ensuring the quality of construction projects, through effective management of the project cost, the construction cost can be controlled, the probability of over-budget and other phenomena can be reduced, and the project cost can be controlled within a reasonable range. Next, the article discusses the current situation of project cost management and the whole process of cost management. 展开更多
关键词 project cost management status whole process cost
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The Control of Engineering Cost in the Whole Process of Construction Project Management
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作者 HU Mingming 《外文科技期刊数据库(文摘版)工程技术》 2021年第5期271-273,共5页
With the continuous development of economy and society, China's construction industry has also seen unprecedented progress in recent years. In the process of cost management of current construction projects, whole... With the continuous development of economy and society, China's construction industry has also seen unprecedented progress in recent years. In the process of cost management of current construction projects, whole-process project cost management is a major development trend. In the field of construction engineering, to ensure the all-round implementation of the work, we must pay attention to the management effect, change the concept of cost control, and effectively implement the work concept. In view of the shortcomings of the whole process cost control in the construction project management, this paper puts forward relevant countermeasures and explorations. In order to ensure the safety of construction project funds and improve the overall quality of the project. 展开更多
关键词 architectural engineering whole process manufacturing cost ADMINISTRATION
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