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Pure State Feedback Switching Control Based on the Online Estimated State for Stochastic Open Quantum Systems
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作者 Shuang Cong Zhixiang Dong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第10期2166-2178,共13页
For the n-qubit stochastic open quantum systems,based on the Lyapunov stability theorem and LaSalle’s invariant set principle,a pure state switching control based on on-line estimated state feedback(short for OQST-SF... For the n-qubit stochastic open quantum systems,based on the Lyapunov stability theorem and LaSalle’s invariant set principle,a pure state switching control based on on-line estimated state feedback(short for OQST-SFC)is proposed to realize the state transition the pure state of the target state including eigenstate and superposition state.The proposed switching control consists of a constant control and a control law designed based on the Lyapunov method,in which the Lyapunov function is the state distance of the system.The constant control is used to drive the system state from an initial state to the convergence domain only containing the target state,and a Lyapunov-based control is used to make the state enter the convergence domain and then continue to converge to the target state.At the same time,the continuous weak measurement of quantum system and the quantum state tomography method based on the on-line alternating direction multiplier(QST-OADM)are used to obtain the system information and estimate the quantum state which is used as the input of the quantum system controller.Then,the pure state feedback switching control method based on the on-line estimated state feedback is realized in an n-qubit stochastic open quantum system.The complete derivation process of n-qubit QST-OADM algorithm is given;Through strict theoretical proof and analysis,the convergence conditions to ensure any initial state of the quantum system to converge the target pure state are given.The proposed control method is applied to a 2-qubit stochastic open quantum system for numerical simulation experiments.Four possible different position cases between the initial estimated state and that of the controlled system are studied and discussed,and the performances of the state transition under the corresponding cases are analyzed. 展开更多
关键词 Online state estimation state feedback control stochastic open quantum systems(OQST) switching control
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Spatial diversion and coordination of flood water for an urban flood control project in Suzhou, China
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作者 Yu Xu You-peng Xu +2 位作者 Qiang Wang Yue-feng Wang Chao Gao 《Water Science and Engineering》 EI CAS CSCD 2024年第2期108-117,共10页
Suzhou City,located in the Yangtze River Delta in China,is prone to flooding due to a complex combination of natural factors,including its monsoon climate,low elevation,and tidally influenced position,as well as inten... Suzhou City,located in the Yangtze River Delta in China,is prone to flooding due to a complex combination of natural factors,including its monsoon climate,low elevation,and tidally influenced position,as well as intensive human activities.The Large Encirclement Flood Control Project(LEFCP)was launched to cope with serious floods in the urban area.This project changed the spatiotemporal pattern of flood processes and caused spatial diversion of floods from the urban area to the outskirts of the city.Therefore,this study developed a distributed flood simulation model in order to understand this transition of flood processes.The results revealed that the LEFCP effectively protected the urban areas from floods,but the present scheduling schemes resulted in the spatial diversion of floods to the outskirts of the city.With rainstorm frequencies of 10.0%to 0.5%,the water level differences between two representative water level stations(Miduqiao(MDQ)and Fengqiao(FQ))located inside and outside the LEFCP area,ranged from 0.75 m to 0.24 m and from 1.80 m to 1.58 m,respectively.In addition,the flood safety margin at MDQ and the duration with the water level exceeding the warning water level at FQ ranged from 0.95 m to 0.43 m and from 4 h to 22 h,respectively.Rational scheduling schemes for the hydraulic facilities of the LEFCP in extreme precipitation cases were developed ac-cording to food simulations under seven scheduling scenarios.This helps to regulate the spatial flood diversion caused by the LEFCP during extreme precipitation. 展开更多
关键词 Urban flooding Urban flood control project Rainstorm fregue ncy Flood simulation model Suzhou City
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Cost Control Strategies for Hubei General Highway Greening Project
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作者 ZHANG Qian HUANG Yaojun AN Yunhua 《Journal of Landscape Research》 2024年第4期17-20,共4页
In order to respond to the national policy of focusing on the service of building a new development pattern and promoting high-quality development,and to reduce the cost of greening projects while ensuring the effect ... In order to respond to the national policy of focusing on the service of building a new development pattern and promoting high-quality development,and to reduce the cost of greening projects while ensuring the effect of highway landscape,a process and cost control points of highway greening design,construction,and maintenance are summarized through a review of the literature.Additionally,this paper examines the attributes of highway greening and proposes cost control strategies that are aligned with these attributes.It is proposed that the implementation of cost control strategies for highway greening should commence at the project establishment phase,with the objective of establishing a comprehensive and effective cost management control system.While guaranteeing the greening landscape effect and the duration of the project,it is essential to regulate the crucial nodes in each phase of the design,construction,and maintenance process.Furthermore,it is vital to facilitate close collaboration between all parties involved,thereby reducing costs,conserving resources,and lowering energy consumption.This approach can also lead to enhanced economic and social benefits for highway greening projects. 展开更多
关键词 General highway Highway greening Greening project Cost control
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Study on Influencing Factors and Control Points of Design Estimate of Landscaping Engineering
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作者 Dan Zhang Meng Wu +1 位作者 Jiashuo Zhao Jie Di 《Journal of Architectural Research and Development》 2024年第5期13-19,共7页
In recent years,China’s landscaping projects have developed vigorously,and the growth rate of urban garden green space areas has been maintained at about 5%.Overall,with the development of the national economy and th... In recent years,China’s landscaping projects have developed vigorously,and the growth rate of urban garden green space areas has been maintained at about 5%.Overall,with the development of the national economy and the support of macro policies,people’s demand for close to nature and beautify the environment is gradually increasing,which has brought new growth momentum for the development of the landscaping industry.Simultaneously,from the perspective of future economic development and urban development,the landscaping industry still has a lot of room for development.However,with the rapid development of landscape engineering,the problem of cost control of landscape engineering is becoming more prominent,the phenomenon of budget overestimation is common,and there are many factors affecting the cost of landscape engineering,which brings difficulties and challenges to the analysis of its influencing factors and cost management.How to scientifically analyze the influencing factors and control the cost has become an important link in the landscaping project.To solve the above problems,this paper takes the design stage of landscaping engineering as the background,takes the design estimate of landscaping engineering as the research object,through literature research and data collection,fully excavates the main influencing factors of the design estimate stage of landscaping engineering,analyzes the key points of cost control,and provides reference ideas and directions for the later cost management and control. 展开更多
关键词 Landscape engineering Design estimate Main influencing factors Cost control
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Temperature Control System with Multi-closed Loops for Lithography Projection Lens 被引量:4
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作者 NIE Hongfei LI Xiaoping HE Yan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第2期207-213,共7页
Image quality is one of the most important specifications of optical lithography tool and is affected notably by temperature, vibration, and contamination of projection lens(PL). Traditional method of local temperat... Image quality is one of the most important specifications of optical lithography tool and is affected notably by temperature, vibration, and contamination of projection lens(PL). Traditional method of local temperature control is easier to introduce vibration and contamination, so temperature control system with multi-closed loops is developed to control the temperature inside the PL, and to isolate the influence of vibration and contamination. A new remote indirect-temperature-control(RITC) method is proposed in which cooling water is circulated to perform indirect-temperature-control of the PL. Heater and cooler embedded temperature control unit(TCU) is used to condition the temperature of the cooling water, and the TCU must be kept away from the PL so that the influence of vibration and contamination can be avoided. A new multi-closed loops control structure incorporating an internal cascade control structure(CCS) and an external parallel cascade control structure(PCCS) is designed to prevent large inertia, multi-delay, and multi-disturbance of the RITC system. A nonlinear proportional-integral(PI) algorithm is applied to further enhance the convergence rate and precision of the control process. Contrast experiments of different control loops and algorithms were implemented to verify the impact on the control performance. It is shown that the temperature control system with multi-closed loops reaches a precision specification at ±0.006 ℃ with fast convergence rate, strong robustness, and self-adaptability. This method has been successfully used in an optical lithography tool which produces a pattern of 100 nm critical dimension(CD), and its performances are satisfactory. 展开更多
关键词 projection lens remote indirect-temperature-control cascade control structure parallel cascade control structure nonlinear proportional-integral(PI) algorithm
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A Priori and A Posteriori Error Estimates of Streamline Diffusion Finite Element Method for Optimal Control Problem Governed by Convection Dominated Diffusion Equation 被引量:5
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作者 Ningning Yan Zhaojie Zhou 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2008年第3期297-320,共24页
In this paper,we investigate a streamline diffusion finite element approxi- mation scheme for the constrained optimal control problem governed by linear con- vection dominated diffusion equations.We prove the existenc... In this paper,we investigate a streamline diffusion finite element approxi- mation scheme for the constrained optimal control problem governed by linear con- vection dominated diffusion equations.We prove the existence and uniqueness of the discretized scheme.Then a priori and a posteriori error estimates are derived for the state,the co-state and the control.Three numerical examples are presented to illustrate our theoretical results. 展开更多
关键词 Constrained optimal control problem convection dominated diffusion equation stream-line diffusion finite element method a priori error estimate a posteriori error estimate.
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Cost Control research in Construction Project Management
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作者 Danjing wang 《International Journal of Technology Management》 2013年第4期98-100,共3页
Construction project management as an important branch of management science has its own characteristics; it was known as an important aspect of project management in the 21 st century. Construction companies now face... Construction project management as an important branch of management science has its own characteristics; it was known as an important aspect of project management in the 21 st century. Construction companies now face a more complex competitive environment and more powerful competitors. In order to compete for the market and living space, Enterprises should be in a strategic height, cultivate long- term competitive advantage. Cost management is a new tool to enhance the competitiveness of enterprises, Popularization and application of Construction project management to the scientific development of the project management made the following three aspects urgent requirement. First. establish a scientific system for the construction project management. Construction Project Management knowledge system is the foundation and needs for Construction Project Management scientific and professional. 展开更多
关键词 Cost control Construction project Management Quality control.
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Study on Safeguard System of Eco-tourism Compensation of Hukou Section during Ecological Water-control Project of Poyang Lake 被引量:1
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作者 龚双双 沈中印 +1 位作者 孙冬英 杨云仙 《Journal of Landscape Research》 2010年第12期58-62,72,共6页
Through analysis on the background to develop eco-tourism and necessity for ecological compensation,based on specific condition of Hukou County,in line with the situation to develop eco-tourism during ecological water... Through analysis on the background to develop eco-tourism and necessity for ecological compensation,based on specific condition of Hukou County,in line with the situation to develop eco-tourism during ecological water control project of Poyang Lake,residents' interest protection system and ecological benefit safeguard system for eco-tourism compensation were put forward. 展开更多
关键词 Poyang Lake ECOLOGICAL WATER control project ECO-TOURISM COMPENSATION Hukou SECTION
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Generalized projective synchronization of chaotic systems via adaptive learning control 被引量:19
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作者 孙云平 李俊民 +1 位作者 王江安 王辉林 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第2期119-126,共8页
In this paper, a learning control approach is applied to the generalized projective synchronisation (GPS) of different chaotic systems with unknown periodically time-varying parameters. Using the Lyapunov--Krasovski... In this paper, a learning control approach is applied to the generalized projective synchronisation (GPS) of different chaotic systems with unknown periodically time-varying parameters. Using the Lyapunov--Krasovskii functional stability theory, a differential-difference mixed parametric learning law and an adaptive learning control law are constructed to make the states of two different chaotic systems asymptotically synchronised. The scheme is successfully applied to the generalized projective synchronisation between the Lorenz system and Chen system. Moreover, numerical simulations results are used to verify the effectiveness of the proposed scheme. 展开更多
关键词 generalized projective synchronisation chaotic systems adaptive learning control Lyapunov--Krasovskii functional
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Chaos Control and Modified Projective Synchronization of Chaotic Dissipative Gyroscope Systems
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作者 Faezeh Farivar Mahdi Aliyari Shoorehdeli +1 位作者 Mohammad Teshnehlabs Mohammad Ali Nekoui 《Journal of Energy and Power Engineering》 2012年第1期90-100,共11页
This paper proposes the chaos control and the modified projective synchronization methods for chaotic dissipative gyroscope systems. Because of the nonlinear terms of the gyroscope system, the system exhibits chaotic ... This paper proposes the chaos control and the modified projective synchronization methods for chaotic dissipative gyroscope systems. Because of the nonlinear terms of the gyroscope system, the system exhibits chaotic motions. Occasionally, the extreme sensitivity to initial states in a system operating in chaotic mode can be very destructive to the system because of unpredictable behavior. In order to improve the performance of a dynamic system or avoid the chaotic phenomena, it is necessary to control a chaotic system with a periodic motion beneficial for working with a particular condition. As chaotic signals are usually broadband and noise like, synchronized chaotic systems can be used as cipher generators for secure communication. This paper presents chaos synchronization of two identical chaotic motions of symmetric gyroscopes. Using the variable structure control technique, control laws are established which guarantees the chaos control and the modified projective synchronization. By Lyapunov stability theory, control lows are proposed to ensure the stability of the controlled and synchronized system. Numerical simulations are presented to verify the proposed control and the synchronization approach. This paper demonstrates that synchronization and anti-synchronization can coexist in dissipative gyroscope systems via variable structure control. 展开更多
关键词 Dissipative gyroscope chaos control modified projective synchronization variable structure control.
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Adaptive Control and Function Projective Synchronization in 2D Discrete-Time Chaotic Systems 被引量:7
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作者 LI Yin CHEN Yong LI Biao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期270-278,共9页
This study addresses the adaptive control and function projective synchronization problems between 2D Rulkov discrete-time system and Network discrete-time system. Based on backstepping design with three controllers, ... This study addresses the adaptive control and function projective synchronization problems between 2D Rulkov discrete-time system and Network discrete-time system. Based on backstepping design with three controllers, a systematic, concrete and automatic scheme is developed to investigate the function projective synchronization of discretetime chaotic systems. In addition, the adaptive control function is applied to achieve the state synchronization of two discrete-time systems. Numerical results demonstrate the effectiveness of the proposed control scheme. 展开更多
关键词 adaptive function projective synchronization backstepping design adaptive control discrete-time chaotic system
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Generalized projective synchronization of the fractional-order chaotic system using adaptive fuzzy sliding mode control 被引量:3
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作者 王立明 唐永光 +1 位作者 柴永泉 吴峰 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第10期64-70,共7页
An adaptive fuzzy sliding mode strategy is developed for the generalized projective synchronization of a fractional- order chaotic system, where the slave system is not necessarily known in advance. Based on the desig... An adaptive fuzzy sliding mode strategy is developed for the generalized projective synchronization of a fractional- order chaotic system, where the slave system is not necessarily known in advance. Based on the designed adaptive update laws and the linear feedback method, the adaptive fuzzy sliding controllers are proposed via the fuzzy design, and the strength of the designed controllers can he adaptively adjusted according to the external disturbances. Based on the Lya- punov stability theorem, the stability and the robustness of the controlled system are proved theoretically. Numerical simu- lations further support the theoretical results of the paper and demonstrate the efficiency of the proposed method. Moreover, it is revealed that the proposed method allows us to manipulate arbitrarily the response dynamics of the slave system by adjusting the desired scaling factor λi and the desired translating factor ηi, which may be used in a channel-independent chaotic secure communication. 展开更多
关键词 generalized projective chaos synchronization fuzzy sliding mode control fractional order chaoticsystem
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Particle Swarm-Based Translation Control for Immersed Tunnel Element in the Hong Kong–Zhuhai–Macao Bridge Project 被引量:2
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作者 LI Jun-jun YANG Xiao-jun +2 位作者 XIAO Ying-jie XU Bo-wei WU Hua-feng 《China Ocean Engineering》 SCIE EI CSCD 2018年第1期32-40,共9页
Immersed tunnel is an important part of the Hong Kong–Zhuhai–Macao Bridge(HZMB) project. In immersed tunnel floating, translation which includes straight and transverse movements is the main working mode. To decide ... Immersed tunnel is an important part of the Hong Kong–Zhuhai–Macao Bridge(HZMB) project. In immersed tunnel floating, translation which includes straight and transverse movements is the main working mode. To decide the magnitude and direction of the towing force for each tug, a particle swarm-based translation control method is presented for non-power immersed tunnel element. A sort of linear weighted logarithmic function is exploited to avoid weak subgoals. In simulation, the particle swarm-based control method is evaluated and compared with traditional empirical method in the case of the HZMB project. Simulation results show that the presented method delivers performance improvement in terms of the enhanced surplus towing force. 展开更多
关键词 immersed tunnel element translation control Hong Kong–Zhuhai–Macao Bridge(HZMB) project particle swarm optimization
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Control and Management of Construction Project Cost 被引量:1
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作者 ZHU Lili 《Journal of Landscape Research》 2016年第4期7-8,共2页
Project cost can control the input in construction project and improve economic benefits of construction enterprises,so it is an important section of construction engineering.Reasonable control and management of proje... Project cost can control the input in construction project and improve economic benefits of construction enterprises,so it is an important section of construction engineering.Reasonable control and management of project cost is the principle that building units must obey in the whole process of project,particularly in the construction stage,so it is extremely important to control and manage the project cost.This paper first analyzed possible causes for the unreasonable cost of construction projects,and put forward pertinent strategies for the control and management of construction project cost. 展开更多
关键词 Construction project Construction stage project cost control and management
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Modified Projective Synchronization of a New Hyperchaotic System via Nonlinear Control 被引量:1
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作者 LI Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第8期274-278,共5页
In this paper, a nonlinear control scheme of two identical hyperchaotic Chert systems is developed to realize their modified projective synchronization. We achieve modified projective synchronization between the two i... In this paper, a nonlinear control scheme of two identical hyperchaotic Chert systems is developed to realize their modified projective synchronization. We achieve modified projective synchronization between the two identical hyperchaotic systems by directing the scaling factor onto the desired value. With symbolic computation system Maple and Lyapunov stability theory, numerical simulations are given to perform the process of the synchronization. 展开更多
关键词 modified projective synchronization nonlinear control method hyperchaotic Chen system
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Control Measures of Soil Erosion in a Typical Construction Project Area ( Dina 2 Gas Field)
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作者 Huiming Lv 《Meteorological and Environmental Research》 CAS 2013年第2期53-58,共6页
To treat the relationship between project construction and ecological environment and effectively prevent new soil erosion during the construction, according to the project layout, soil erosion distribution as well as... To treat the relationship between project construction and ecological environment and effectively prevent new soil erosion during the construction, according to the project layout, soil erosion distribution as well as natural and socio-economic conditions, the control measures of newly increased soil erosion along the project were carried out based on site survey and analysis of relevant information. In addition, adhering to the prin- ciple of partition prevention and treatment, some guiding prevention and control measures of the natural zone passed by the project and soil erosion control district were determined, which provided scientific references and technical support for the rational layout of water and soil conservation and ecological restoration measures in Dina 2 gas field. 展开更多
关键词 Typical construction project area Dina 2 gas field Ecological environment Soil erosion control measures China
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A Study on Cost Control of Agricultural Water Conservancy Projects Based on Activity-based Costing
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作者 Tiantian TANG 《Asian Agricultural Research》 2017年第7期11-14,共4页
Based on the theory of activity-based costing and the idea of value chain,activity optimization and cost control are carried out on the whole construction process of agricultural water conservancy projects. Through th... Based on the theory of activity-based costing and the idea of value chain,activity optimization and cost control are carried out on the whole construction process of agricultural water conservancy projects. Through the use of literature review,case analysis and statistical analysis and other methods,with agricultural water conservancy projects as the research object,and comparing activity-based costing with the traditional model of cost accounting,the writer carries out the corresponding value chain analysis,and comes to the following conclusion: the statistical calculation and analysis of the entire construction process based on activity-based costing can accurately and effectively control the costs of water conservancy projects. Through the use of activity-based costing,the cost data of agricultural water conservancy projects is more detailed and accurate,and cost management personnel can also find non-value-added activities,optimize the enterprise's value chain and achieve cost control objectives through the analysis of the activity chain and value chain of agricultural water conservancy projects. 展开更多
关键词 Activity-based costing Agricultural water conservancy projects Cost control
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The flood control and regulation of Three Gorges Project
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作者 Cai Qihua 《Engineering Sciences》 EI 2011年第3期15-21,共7页
The important role of Three Gorges Project (TGP) in the flood management of the Yangtze River Basin is summarized.The Optimal Regulation Schemes of the Three Gorge Reservoir is briefly described.The flood regulation e... The important role of Three Gorges Project (TGP) in the flood management of the Yangtze River Basin is summarized.The Optimal Regulation Schemes of the Three Gorge Reservoir is briefly described.The flood regulation effect of TGP is analyzed.Typical issues related to reservoir operation for flood regulation are discussed and suggestions are put forward for the future work. 展开更多
关键词 Three Gorges project flood control REGULATION
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Control and Management Measures of Highway Project Cost under the PPP Model
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作者 Hanzhi Kou 《Journal of Architectural Research and Development》 2021年第1期17-20,共4页
In recent years,China’s society and economy has been developing very rapidly,and various industries are showing a trend of vigorous development.The importance of control and management of project cost in highway proj... In recent years,China’s society and economy has been developing very rapidly,and various industries are showing a trend of vigorous development.The importance of control and management of project cost in highway project management is becoming more and more prominent.PPP model has been widely used in the control and management of highway project cost with its own unique advantages.The author analyzes the important advantages of the PPP model and the existing problems in the cost control and management of highway projects,and puts forward effective measures for the cost control and management of highway projects using the PPP model,in hope of helping with the smooth implementation of the work. 展开更多
关键词 PPP model Highway project COST control and management
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Investment control in whole process of engineering construction project
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作者 Wei Zuo Zhenkai Xie Lili Dou 《International English Education Research》 2014年第8期74-76,共3页
in recent years, as the project of our country is increasing, investment growth, put forward new challenges to investment in construction projects. Research from the research status of investment in construction, the ... in recent years, as the project of our country is increasing, investment growth, put forward new challenges to investment in construction projects. Research from the research status of investment in construction, the implementation process in accordance with the construction project, followed by analysis of the construction project investment the currently existing problems, and puts forward the implementation of the project the whole process as the main line, to scientific decision-making, rational design, bidding, construction control standard and completion of review strategies as the core. 展开更多
关键词 construction project investment control the whole process
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