In the process of China’s national economic development,the construction industry is a very important component and has a direct impact on the level of China’s economic construction.Nowadays,the development speed of...In the process of China’s national economic development,the construction industry is a very important component and has a direct impact on the level of China’s economic construction.Nowadays,the development speed of the prefabricated construction industry is constantly accelerating.To effectively ensure the economic benefits of engineering projects,it is necessary to comprehensively strengthen cost budgeting and cost control.This article analyzes the cost budget of prefabricated construction projects,introduces the application advantages of prefabricated construction,and proposes specific cost budgeting and cost control measures,hoping to provide some reference for relevant researchers.展开更多
With the sky-rocketing development of Internet services, the power usage in data centers has been signifi- cantly increasing. This ever increasing energy consumption leads to negative environmental impact such as glob...With the sky-rocketing development of Internet services, the power usage in data centers has been signifi- cantly increasing. This ever increasing energy consumption leads to negative environmental impact such as global warming. To reduce their carbon footprints, large Internet service operators begin to utilize green energy. Since green energy is currently more expensive than the traditional brown one, it is important for the operators to maximize the green en- ergy usage subject to their desired long-term （e.g., a month） cost budget constraint. In this paper, we propose an online algorithm GreenBudget based on the Lyapunov optimization framework. We prove that our algorithm is able to achieve a delicate tradeoff between the green energy usage and the en- forcement of the cost budget constraint, and a control parameter V is the knob to arbitrarily tune such a tradeoff. We evaluate GreenBudget utilizing real-life traces of user requests, cooling efficiency, electricity price and green energy avail- ability. Experimental results demonstrate that under the same cost budget constraint, GreenBudget can increase the green energy usage by 11.55% compared with the state-of-the-art work, without incurring any performance violation of user requests.展开更多
Time, cost and quality are the three main targets to be controled in project management. However, the control and management of time and cost risk are usually carried out respectively, which will bring such problems a...Time, cost and quality are the three main targets to be controled in project management. However, the control and management of time and cost risk are usually carried out respectively, which will bring such problems as the delay of schedule by reason of the impracticability of cash flow, the money difficulties caused by delay of schedule and so on. In order to control and manage the time and cost risk effectively and simultaneously, a time & cost risk control model based on schedule programme was established with the use of the quantitativemodels of BCWS, BCWP and ACWP in this paper. Subsequently, the analysis of variance for the whole project and the single activity was introduced on the basis of BCWS, BCWP and ACWP so that the project can be controlled and managed effectively. Furthermore, an example given behind in detail expressly illustrated that the model set up above was practicableto project management. However, the method of optimizing the cash flow based on time and cost risk to obtain BCWS should be considered properlyand carefully with respect to the different circumstances of the project, and an efficient and adequate interval report system should be set up on the site of the project.展开更多
Medical education is associated with significant costs[1].These costs have led to a growing interest in how to deliver high quality or high quantity education on a limited budget.This in turn has led to an interest in...Medical education is associated with significant costs[1].These costs have led to a growing interest in how to deliver high quality or high quantity education on a limited budget.This in turn has led to an interest in how best to measure quantity,quality and cost and how to track these variables over time.The ultimate aim of the interest in cost and value in medical education is to展开更多
We think we should use basic return rate of industry to measure the opportunity cost of capital and use the rule of Maximum NPV （Net Present Value） to modify the wrong solution in the book.
The operational stability and economy of multi-energy systems(MES)are threatened by various uncertainties,such as variable renewable energy power,energy demands,and weather conditions.Most of the existing methods for ...The operational stability and economy of multi-energy systems(MES)are threatened by various uncertainties,such as variable renewable energy power,energy demands,and weather conditions.Most of the existing methods for the dispatch decisions of MES are based on the prescribed probability distribution or uncertainty sets of random variables,which have many disadvantages,such as potential infeasibility and over-conservatism.In this paper,we propose a novel dispatch model for MES that integrates dispatch decision making,uncertainty set selection,and operational cost control into a unified framework.First,the deterministic dispatch model of MES is introduced,in which the physical characteristics of district heating systems and buildings are fully considered.Then,a novel decision framework that combines the two-stage dispatch strategy and info-gap decision theory(IGDT)is proposed for MES,where the uncertainty set is flexible and can be optimized based on the operational cost budget.Finally,a revised algorithm,based on the column-and-constraint generation method,is proposed for the model.Case studies are performed on MES that includes a 33-bus distribution system and a heating network modified from a real 51-node network located in Jinlin Province,China.The results verify the effectiveness of the proposed method.展开更多
文摘In the process of China’s national economic development,the construction industry is a very important component and has a direct impact on the level of China’s economic construction.Nowadays,the development speed of the prefabricated construction industry is constantly accelerating.To effectively ensure the economic benefits of engineering projects,it is necessary to comprehensively strengthen cost budgeting and cost control.This article analyzes the cost budget of prefabricated construction projects,introduces the application advantages of prefabricated construction,and proposes specific cost budgeting and cost control measures,hoping to provide some reference for relevant researchers.
文摘With the sky-rocketing development of Internet services, the power usage in data centers has been signifi- cantly increasing. This ever increasing energy consumption leads to negative environmental impact such as global warming. To reduce their carbon footprints, large Internet service operators begin to utilize green energy. Since green energy is currently more expensive than the traditional brown one, it is important for the operators to maximize the green en- ergy usage subject to their desired long-term （e.g., a month） cost budget constraint. In this paper, we propose an online algorithm GreenBudget based on the Lyapunov optimization framework. We prove that our algorithm is able to achieve a delicate tradeoff between the green energy usage and the en- forcement of the cost budget constraint, and a control parameter V is the knob to arbitrarily tune such a tradeoff. We evaluate GreenBudget utilizing real-life traces of user requests, cooling efficiency, electricity price and green energy avail- ability. Experimental results demonstrate that under the same cost budget constraint, GreenBudget can increase the green energy usage by 11.55% compared with the state-of-the-art work, without incurring any performance violation of user requests.
文摘Time, cost and quality are the three main targets to be controled in project management. However, the control and management of time and cost risk are usually carried out respectively, which will bring such problems as the delay of schedule by reason of the impracticability of cash flow, the money difficulties caused by delay of schedule and so on. In order to control and manage the time and cost risk effectively and simultaneously, a time & cost risk control model based on schedule programme was established with the use of the quantitativemodels of BCWS, BCWP and ACWP in this paper. Subsequently, the analysis of variance for the whole project and the single activity was introduced on the basis of BCWS, BCWP and ACWP so that the project can be controlled and managed effectively. Furthermore, an example given behind in detail expressly illustrated that the model set up above was practicableto project management. However, the method of optimizing the cash flow based on time and cost risk to obtain BCWS should be considered properlyand carefully with respect to the different circumstances of the project, and an efficient and adequate interval report system should be set up on the site of the project.
文摘Medical education is associated with significant costs[1].These costs have led to a growing interest in how to deliver high quality or high quantity education on a limited budget.This in turn has led to an interest in how best to measure quantity,quality and cost and how to track these variables over time.The ultimate aim of the interest in cost and value in medical education is to
文摘We think we should use basic return rate of industry to measure the opportunity cost of capital and use the rule of Maximum NPV （Net Present Value） to modify the wrong solution in the book.
基金the National Science Foundation of China(52207080)in part by the State Grid Jiangsu Electric Power Company Science and Technology Project(J2020001)in part by the National Science Foundation of Jiangsu Province(BK20200404).
文摘The operational stability and economy of multi-energy systems(MES)are threatened by various uncertainties,such as variable renewable energy power,energy demands,and weather conditions.Most of the existing methods for the dispatch decisions of MES are based on the prescribed probability distribution or uncertainty sets of random variables,which have many disadvantages,such as potential infeasibility and over-conservatism.In this paper,we propose a novel dispatch model for MES that integrates dispatch decision making,uncertainty set selection,and operational cost control into a unified framework.First,the deterministic dispatch model of MES is introduced,in which the physical characteristics of district heating systems and buildings are fully considered.Then,a novel decision framework that combines the two-stage dispatch strategy and info-gap decision theory(IGDT)is proposed for MES,where the uncertainty set is flexible and can be optimized based on the operational cost budget.Finally,a revised algorithm,based on the column-and-constraint generation method,is proposed for the model.Case studies are performed on MES that includes a 33-bus distribution system and a heating network modified from a real 51-node network located in Jinlin Province,China.The results verify the effectiveness of the proposed method.
