In order to cope with the increasing threat of the ballistic missile(BM)in a shorter reaction time,the shooting policy of the layered defense system needs to be optimized.The main decisionmaking problem of shooting op...In order to cope with the increasing threat of the ballistic missile(BM)in a shorter reaction time,the shooting policy of the layered defense system needs to be optimized.The main decisionmaking problem of shooting optimization is how to choose the next BM which needs to be shot according to the previous engagements and results,thus maximizing the expected return of BMs killed or minimizing the cost of BMs penetration.Motivated by this,this study aims to determine an optimal shooting policy for a two-layer missile defense(TLMD)system.This paper considers a scenario in which the TLMD system wishes to shoot at a collection of BMs one at a time,and to maximize the return obtained from BMs killed before the system demise.To provide a policy analysis tool,this paper develops a general model for shooting decision-making,the shooting engagements can be described as a discounted reward Markov decision process.The index shooting policy is a strategy that can effectively balance the shooting returns and the risk that the defense mission fails,and the goal is to maximize the return obtained from BMs killed before the system demise.The numerical results show that the index policy is better than a range of competitors,especially the mean returns and the mean killing BM number.展开更多
This paper studies the optimal policy for joint control of admission, routing, service, and jockeying in a queueing system consisting of two exponential servers in parallel.Jobs arrive according to a Poisson process.U...This paper studies the optimal policy for joint control of admission, routing, service, and jockeying in a queueing system consisting of two exponential servers in parallel.Jobs arrive according to a Poisson process.Upon each arrival, an admission/routing decision is made, and the accepted job is routed to one of the two servers with each being associated with a queue.After each service completion, the servers have an option of serving a job from its own queue, serving a jockeying job from another queue, or staying idle.The system performance is inclusive of the revenues from accepted jobs, the costs of holding jobs in queues, the service costs and the job jockeying costs.To maximize the total expected discounted return, we formulate a Markov decision process(MDP) model for this system.The value iteration method is employed to characterize the optimal policy as a hedging point policy.Numerical studies verify the structure of the hedging point policy which is convenient for implementing control actions in practice.展开更多
It is a social system engineering to solve problems of city agricultural laborers, inevitably concerning series of social phenomenon and the social issues of the city and countryside relations, the government function...It is a social system engineering to solve problems of city agricultural laborers, inevitably concerning series of social phenomenon and the social issues of the city and countryside relations, the government function, the city management, the fair efficiency, the population flows, the labor employment, the social security, and so on. Furthermore, it also involves the profoundly political and economic system reforms, the transformation of government functions, the system perfection, legal administration, the social stability in China. The city government, as the direct superintendent of the agricultural laborers, should adopt the conception of the system engineering to construct a new mechanism of the city agricultural laborers socialization standard management, which has a profound theoretical and practical significance.展开更多
The maintenance model of simple repairable system is studied.We assume that there are two types of failure,namely type Ⅰ failure(repairable failure)and type Ⅱ failure(irrepairable failure).As long as the type Ⅰ fai...The maintenance model of simple repairable system is studied.We assume that there are two types of failure,namely type Ⅰ failure(repairable failure)and type Ⅱ failure(irrepairable failure).As long as the type Ⅰ failure occurs,the system will be repaired immediately,which is failure repair(FR).Between the(n-1)th and the nth FR,the system is supposed to be preventively repaired(PR)as the consecutive working time of the system reaches λ^(n-1) T,where λ and T are specified values.Further,we assume that the system will go on working when the repair is finished and will be replaced at the occurrence of the Nth type Ⅰ failure or the occurrence of the first type Ⅱ failure,whichever occurs first.In practice,the system will degrade with the increasing number of repairs.That is,the consecutive working time of the system forms a decreasing generalized geometric process(GGP)whereas the successive repair time forms an increasing GGP.A simple bivariate policy(T,N)repairable model is introduced based on GGP.The alternative searching method is used to minimize the cost rate function C(N,T),and the optimal(T,N)^(*) is obtained.Finally,numerical cases are applied to demonstrate the reasonability of this model.展开更多
Policy被越来越多地应用于大型分布式系统的管理 .提出了一种基于逻辑的 Policy定义语言 L PDL ,定义了 L PDL的语法、运行模型和语义 ,为基于 Policy的网络管理提供了一种形式化的框架 .L PDL具有简单的语法规则和与图灵机等价的计算能...Policy被越来越多地应用于大型分布式系统的管理 .提出了一种基于逻辑的 Policy定义语言 L PDL ,定义了 L PDL的语法、运行模型和语义 ,为基于 Policy的网络管理提供了一种形式化的框架 .L PDL具有简单的语法规则和与图灵机等价的计算能力 ,管理人员可以根据实际需要 ,灵活地将系统的解释决策功能用 L PDL语言定义成Policy或封装在系统物理实现代码中 .最后给出了基于 L PDL 的网络管理模型及其原型实现和应用 ,表明 L PDL能很好满足网络管理动态发展的需要 .展开更多
The direct cause for the voidance of economic policy is that the government has ignored the game behavior of the microeconomy.Only if we formulate and implement policy strictly according to the game rules can it be pr...The direct cause for the voidance of economic policy is that the government has ignored the game behavior of the microeconomy.Only if we formulate and implement policy strictly according to the game rules can it be promoted to realize its desired objective.展开更多
An optimal replacement model for gamma deteriorating systems is studied. This methodology uses a gamma distribution to model the material degradation, and the impact of imperfect maintenance actions on the system reli...An optimal replacement model for gamma deteriorating systems is studied. This methodology uses a gamma distribution to model the material degradation, and the impact of imperfect maintenance actions on the system reliability is investigated. The state of a degrading system immediately after the imperfect maintenance action is assumed as a random variable and the maintenance time follows a geometric process. A maintenance policy （N） is applied by which the system will be repaired whenever it experiences Nth preventive maintenance （PM）, and an optimal policy （N＊） could be determined numerically or analytically for minimizing the long-run average cost per unit time. Finally, a numerical example is presented to demonstrate the use of this policy.展开更多
An opportunistic maintenance model is presented for a continuously deteriorating series system with economical de-pendence. The system consists of two kinds of units, which are respectively subjected to the deteriorat...An opportunistic maintenance model is presented for a continuously deteriorating series system with economical de-pendence. The system consists of two kinds of units, which are respectively subjected to the deterioration failure described by Gamma process and the random failure described by Poisson process. A two-level opportunistic policy defined by three decision parameters is proposed to coordinate the different maintenance actions and minimize the long-run maintenance cost rate of the system. A computable expression of the average cost rate is established by using the renewal property of the stochastic process of the maintained system state. The optimal values of three deci- sion parameters are derived by an iteration approach based on the characteristic of Gamma process. The behavior of the proposed policy is illustrated through a numerical experiment. Comparative study with the widely used corrective maintenance policy demonstrates the advantage of the proposed opportunistic maintenance method in significantly reducing the maintenance cost. Simultane- ously, the applicable area of this opportunistic model is discussed by the sensitivity analysis of the set-up cost and random failure rate.展开更多
The availability of a periodic inspection system under mixed maintenance policies is studied in this paper.To accommodate the characteristic of multiple failure modes for complex systems,the system failures can be div...The availability of a periodic inspection system under mixed maintenance policies is studied in this paper.To accommodate the characteristic of multiple failure modes for complex systems,the system failures can be divided into two failure modes:hard failure and soft failure.When hard failure occurs,the corresponding corrective maintenance will be performed,taking a random time under the perfect maintenance policy;in contrast,if the soft failure is found,the corresponding preventive maintenance will be performed,taking a random time under the imperfect maintenance policy.The dynamic age setback model is adopted for imperfect maintenance,which can accurately reflect the fault characteristics of the degraded system.Then an analytical model for system steady state availability and instantaneous availability are derived.Moreover,the optimal method to maximize the system steady-state availability through adjusting the inspection interval is researched.According to the above research,the optimization of system unit time cost,preventive maintenance intervals and availability is researched.Finally,the developed approach is demonstrated by a numerical example.展开更多
A replenishment decision-making model for supply-hub is firstly established from the angle of supplier, and optimal replenishment decision of the supplier is analyzed. Then, inventory optimization model for supply-hub...A replenishment decision-making model for supply-hub is firstly established from the angle of supplier, and optimal replenishment decision of the supplier is analyzed. Then, inventory optimization model for supply-hub is formulated from the angle of the manufacturer, and the optimization algorithm for obtaining optimal inventory levels is given. The result shows that liability period decides the share of the inventory cost between two sides in supply chain. With the increase of liability period, the service level has been quickly reduced even though the manufacturer's cost has been cut down by transferring the inventory cost to the supplier. As to the safety inventory, if the lower bound of components safety inventory increases, the supplier's cost will rise up more slowly than the liability period does, while the service levels increases as the safety inventory's lower bound is raised.展开更多
The land use planning system in England is governed by legislation which is implemented through national policy and incorporated into development plans.Regional and local development plans form the basis for the plann...The land use planning system in England is governed by legislation which is implemented through national policy and incorporated into development plans.Regional and local development plans form the basis for the planning decisions made by planning officials.Population density in England is very high and competition for land use is intense.Since the introduction of Minerals Policy Statement 1(MPS1)展开更多
A simple repairable system with one repairman is considered. As the system working age is up to a specified time T, the repairman will repair the component preventively, and it will go back to work as soon as the repa...A simple repairable system with one repairman is considered. As the system working age is up to a specified time T, the repairman will repair the component preventively, and it will go back to work as soon as the repair finished. When the system failure, the repairman repair it immediately. The time interval of the preventive repair and the failure correction is described with the extended geometric process. Different from the available replacement policy which is usually based on the failure number or the working age of the system, the bivariate policy (T,N) is considered. The explicit expression of the long-run average cost rate function C(T,N) of the system is derived. Through alternatively minimize the cost rate function C(T,N), the optimal replacement policy (T?,N?) is obtained, and it proves that the optimal policy is unique. Numerical cases illustrate the conclusion, and the sensitivity analysis of the parameters is carried out.展开更多
With the dramatic development of renewable energy all over the world,and for purpose of adjusting energy structure,the Ministry of Construction of China plans to promote the large scale application of renewable energy...With the dramatic development of renewable energy all over the world,and for purpose of adjusting energy structure,the Ministry of Construction of China plans to promote the large scale application of renewable energy in buildings. In order to ensure the validity of policy-making,this work firstly exerts a method to do cost-benefit analysis for three kinds of technologies such as building-integrated solar hot water (BISHW) system,building-integrated photovoltaic (BIPV) technology and ground water heat pump (GWHP). Through selecting a representative city of every climate region,the analysis comes into different results for different climate regions in China and respectively different suggestion for policy-making. On the analysis basis,the Ministry of Construction (MOC) and the Ministry of Finance of China (MOF) united to start-up Building-integrated Renewable Energy Demonstration Projects (BIREDP) in 2006. In the demonstration projects,renewable energy takes place of traditional energy to supply the domestic hot water,electricity,air-conditioning and heating. Through carrying out the demonstration projects,renewable energy related market has been expanded. More and more relative companies and local governments take the opportunity to promote the large scale application of renewable energy in buildings.展开更多
This study explores childcare policy change in South Korea by employing the gradual institutional change model and in relation to the concept of defamilialization.T his study measured the degree of defamilialization q...This study explores childcare policy change in South Korea by employing the gradual institutional change model and in relation to the concept of defamilialization.T his study measured the degree of defamilialization quantitatively using the data of Childcare Statistics between 2001-2016 and conducted hierarchical cluster analysis.The analysis results showed that the trajectories of childcare policy in South Korea could be divided into three clusters-2001-2006 for the first cluster,2007-2012 for the second cluster,and2013-2016 for the third cluster-and there were two changes-conversion and layering.Childcare policy in South Korea has taken the path of familialization,market defamilialization,and active familialization.展开更多
With decades of hard work,socialism with Chinese characteristics has crossed the threshold into a new era.The transformation of the principal contradiction in the new era has imposed new and higher requirements on the...With decades of hard work,socialism with Chinese characteristics has crossed the threshold into a new era.The transformation of the principal contradiction in the new era has imposed new and higher requirements on the rural elderly care service system.However,the current service system based on welfare-multiplex and urban community environment is often difficult to operate in the rural areas of central and western China.And the urban home care service for the aged is inappropriate to the rural reality;community service for the aged faces difficulties in practice;institution care for the aged develops slowly;the synergy among different elderly care service models is poor.Through observing the rural areas of central and western China in the field for a long time,this paper proposes to build the rural elderly care service system based on family supporting,supported by community mutual assistance care,supplemented by institution care for the aged,combined with medical care,and localized with diversified forms for targeted groups according to different realities.And the system should follow the fundamental guidance of development-oriented family policy,adhere to the governance mode of multiple subjects with one core and respect rural reality,which could provide a feasible way for the reform and reconstruction of the rural elderly care service system.展开更多
基金supported by the National Natural Science Foundation of China(7170120971771216)+1 种基金Shaanxi Natural Science Foundation(2019JQ-250)China Post-doctoral Fund(2019M653962)
文摘In order to cope with the increasing threat of the ballistic missile(BM)in a shorter reaction time,the shooting policy of the layered defense system needs to be optimized.The main decisionmaking problem of shooting optimization is how to choose the next BM which needs to be shot according to the previous engagements and results,thus maximizing the expected return of BMs killed or minimizing the cost of BMs penetration.Motivated by this,this study aims to determine an optimal shooting policy for a two-layer missile defense(TLMD)system.This paper considers a scenario in which the TLMD system wishes to shoot at a collection of BMs one at a time,and to maximize the return obtained from BMs killed before the system demise.To provide a policy analysis tool,this paper develops a general model for shooting decision-making,the shooting engagements can be described as a discounted reward Markov decision process.The index shooting policy is a strategy that can effectively balance the shooting returns and the risk that the defense mission fails,and the goal is to maximize the return obtained from BMs killed before the system demise.The numerical results show that the index policy is better than a range of competitors,especially the mean returns and the mean killing BM number.
基金supported by the National Social Science Fund of China (19BGL100)。
文摘This paper studies the optimal policy for joint control of admission, routing, service, and jockeying in a queueing system consisting of two exponential servers in parallel.Jobs arrive according to a Poisson process.Upon each arrival, an admission/routing decision is made, and the accepted job is routed to one of the two servers with each being associated with a queue.After each service completion, the servers have an option of serving a job from its own queue, serving a jockeying job from another queue, or staying idle.The system performance is inclusive of the revenues from accepted jobs, the costs of holding jobs in queues, the service costs and the job jockeying costs.To maximize the total expected discounted return, we formulate a Markov decision process(MDP) model for this system.The value iteration method is employed to characterize the optimal policy as a hedging point policy.Numerical studies verify the structure of the hedging point policy which is convenient for implementing control actions in practice.
基金Supported by Social Sciences Fund of Heilongjiang Province (06B002)
文摘It is a social system engineering to solve problems of city agricultural laborers, inevitably concerning series of social phenomenon and the social issues of the city and countryside relations, the government function, the city management, the fair efficiency, the population flows, the labor employment, the social security, and so on. Furthermore, it also involves the profoundly political and economic system reforms, the transformation of government functions, the system perfection, legal administration, the social stability in China. The city government, as the direct superintendent of the agricultural laborers, should adopt the conception of the system engineering to construct a new mechanism of the city agricultural laborers socialization standard management, which has a profound theoretical and practical significance.
基金supported by the National Natural Science Foundation of China(61573014)the Fundamental Research Funds for the Central Universities(JB180702).
文摘The maintenance model of simple repairable system is studied.We assume that there are two types of failure,namely type Ⅰ failure(repairable failure)and type Ⅱ failure(irrepairable failure).As long as the type Ⅰ failure occurs,the system will be repaired immediately,which is failure repair(FR).Between the(n-1)th and the nth FR,the system is supposed to be preventively repaired(PR)as the consecutive working time of the system reaches λ^(n-1) T,where λ and T are specified values.Further,we assume that the system will go on working when the repair is finished and will be replaced at the occurrence of the Nth type Ⅰ failure or the occurrence of the first type Ⅱ failure,whichever occurs first.In practice,the system will degrade with the increasing number of repairs.That is,the consecutive working time of the system forms a decreasing generalized geometric process(GGP)whereas the successive repair time forms an increasing GGP.A simple bivariate policy(T,N)repairable model is introduced based on GGP.The alternative searching method is used to minimize the cost rate function C(N,T),and the optimal(T,N)^(*) is obtained.Finally,numerical cases are applied to demonstrate the reasonability of this model.
文摘Policy被越来越多地应用于大型分布式系统的管理 .提出了一种基于逻辑的 Policy定义语言 L PDL ,定义了 L PDL的语法、运行模型和语义 ,为基于 Policy的网络管理提供了一种形式化的框架 .L PDL具有简单的语法规则和与图灵机等价的计算能力 ,管理人员可以根据实际需要 ,灵活地将系统的解释决策功能用 L PDL语言定义成Policy或封装在系统物理实现代码中 .最后给出了基于 L PDL 的网络管理模型及其原型实现和应用 ,表明 L PDL能很好满足网络管理动态发展的需要 .
文摘The direct cause for the voidance of economic policy is that the government has ignored the game behavior of the microeconomy.Only if we formulate and implement policy strictly according to the game rules can it be promoted to realize its desired objective.
基金supported by the National Natural Science Foundation of China (60904002)
文摘An optimal replacement model for gamma deteriorating systems is studied. This methodology uses a gamma distribution to model the material degradation, and the impact of imperfect maintenance actions on the system reliability is investigated. The state of a degrading system immediately after the imperfect maintenance action is assumed as a random variable and the maintenance time follows a geometric process. A maintenance policy （N） is applied by which the system will be repaired whenever it experiences Nth preventive maintenance （PM）, and an optimal policy （N＊） could be determined numerically or analytically for minimizing the long-run average cost per unit time. Finally, a numerical example is presented to demonstrate the use of this policy.
基金supported by the National Natural Science Foundation of China(6090400271201166)
文摘An opportunistic maintenance model is presented for a continuously deteriorating series system with economical de-pendence. The system consists of two kinds of units, which are respectively subjected to the deterioration failure described by Gamma process and the random failure described by Poisson process. A two-level opportunistic policy defined by three decision parameters is proposed to coordinate the different maintenance actions and minimize the long-run maintenance cost rate of the system. A computable expression of the average cost rate is established by using the renewal property of the stochastic process of the maintained system state. The optimal values of three deci- sion parameters are derived by an iteration approach based on the characteristic of Gamma process. The behavior of the proposed policy is illustrated through a numerical experiment. Comparative study with the widely used corrective maintenance policy demonstrates the advantage of the proposed opportunistic maintenance method in significantly reducing the maintenance cost. Simultane- ously, the applicable area of this opportunistic model is discussed by the sensitivity analysis of the set-up cost and random failure rate.
基金supported by the China Postdoctoral Science Foundation(2019M653929)the National Natural Science Foundation of Shandong Province(ZR201910310210)the Green Innovation Science and Technology Plan of Colleges and Universities in Shandong Province(2020KJA014).
文摘The availability of a periodic inspection system under mixed maintenance policies is studied in this paper.To accommodate the characteristic of multiple failure modes for complex systems,the system failures can be divided into two failure modes:hard failure and soft failure.When hard failure occurs,the corresponding corrective maintenance will be performed,taking a random time under the perfect maintenance policy;in contrast,if the soft failure is found,the corresponding preventive maintenance will be performed,taking a random time under the imperfect maintenance policy.The dynamic age setback model is adopted for imperfect maintenance,which can accurately reflect the fault characteristics of the degraded system.Then an analytical model for system steady state availability and instantaneous availability are derived.Moreover,the optimal method to maximize the system steady-state availability through adjusting the inspection interval is researched.According to the above research,the optimization of system unit time cost,preventive maintenance intervals and availability is researched.Finally,the developed approach is demonstrated by a numerical example.
基金Projects(71102174,70971036) supported by the National Natural Science Foundation of ChinaProject(9123028) supported by the Beijing Natural Science Foundation,China+3 种基金Project(20111101120019) supported by the Specialized Research Fund for Doctoral Program of Higher Education of ChinaProject(11JGC106) supported by the Beijing Philosophy&Social Science Foundation of ChinaProjects(NCET-10-0048,NCET-10-0043) supported by the Program for New Century Excellent Talents in Universities of ChinaProject(2010YC1307) supported by the Excellent Young Teacher in Beijing Institute of Technology of China
文摘A replenishment decision-making model for supply-hub is firstly established from the angle of supplier, and optimal replenishment decision of the supplier is analyzed. Then, inventory optimization model for supply-hub is formulated from the angle of the manufacturer, and the optimization algorithm for obtaining optimal inventory levels is given. The result shows that liability period decides the share of the inventory cost between two sides in supply chain. With the increase of liability period, the service level has been quickly reduced even though the manufacturer's cost has been cut down by transferring the inventory cost to the supplier. As to the safety inventory, if the lower bound of components safety inventory increases, the supplier's cost will rise up more slowly than the liability period does, while the service levels increases as the safety inventory's lower bound is raised.
文摘The land use planning system in England is governed by legislation which is implemented through national policy and incorporated into development plans.Regional and local development plans form the basis for the planning decisions made by planning officials.Population density in England is very high and competition for land use is intense.Since the introduction of Minerals Policy Statement 1(MPS1)
基金supported by the National Natural Science Foundation of China(61573014)the Fundamental Research Funds for the Central Universities(JB180702)
文摘A simple repairable system with one repairman is considered. As the system working age is up to a specified time T, the repairman will repair the component preventively, and it will go back to work as soon as the repair finished. When the system failure, the repairman repair it immediately. The time interval of the preventive repair and the failure correction is described with the extended geometric process. Different from the available replacement policy which is usually based on the failure number or the working age of the system, the bivariate policy (T,N) is considered. The explicit expression of the long-run average cost rate function C(T,N) of the system is derived. Through alternatively minimize the cost rate function C(T,N), the optimal replacement policy (T?,N?) is obtained, and it proves that the optimal policy is unique. Numerical cases illustrate the conclusion, and the sensitivity analysis of the parameters is carried out.
文摘With the dramatic development of renewable energy all over the world,and for purpose of adjusting energy structure,the Ministry of Construction of China plans to promote the large scale application of renewable energy in buildings. In order to ensure the validity of policy-making,this work firstly exerts a method to do cost-benefit analysis for three kinds of technologies such as building-integrated solar hot water (BISHW) system,building-integrated photovoltaic (BIPV) technology and ground water heat pump (GWHP). Through selecting a representative city of every climate region,the analysis comes into different results for different climate regions in China and respectively different suggestion for policy-making. On the analysis basis,the Ministry of Construction (MOC) and the Ministry of Finance of China (MOF) united to start-up Building-integrated Renewable Energy Demonstration Projects (BIREDP) in 2006. In the demonstration projects,renewable energy takes place of traditional energy to supply the domestic hot water,electricity,air-conditioning and heating. Through carrying out the demonstration projects,renewable energy related market has been expanded. More and more relative companies and local governments take the opportunity to promote the large scale application of renewable energy in buildings.
文摘This study explores childcare policy change in South Korea by employing the gradual institutional change model and in relation to the concept of defamilialization.T his study measured the degree of defamilialization quantitatively using the data of Childcare Statistics between 2001-2016 and conducted hierarchical cluster analysis.The analysis results showed that the trajectories of childcare policy in South Korea could be divided into three clusters-2001-2006 for the first cluster,2007-2012 for the second cluster,and2013-2016 for the third cluster-and there were two changes-conversion and layering.Childcare policy in South Korea has taken the path of familialization,market defamilialization,and active familialization.
文摘With decades of hard work,socialism with Chinese characteristics has crossed the threshold into a new era.The transformation of the principal contradiction in the new era has imposed new and higher requirements on the rural elderly care service system.However,the current service system based on welfare-multiplex and urban community environment is often difficult to operate in the rural areas of central and western China.And the urban home care service for the aged is inappropriate to the rural reality;community service for the aged faces difficulties in practice;institution care for the aged develops slowly;the synergy among different elderly care service models is poor.Through observing the rural areas of central and western China in the field for a long time,this paper proposes to build the rural elderly care service system based on family supporting,supported by community mutual assistance care,supplemented by institution care for the aged,combined with medical care,and localized with diversified forms for targeted groups according to different realities.And the system should follow the fundamental guidance of development-oriented family policy,adhere to the governance mode of multiple subjects with one core and respect rural reality,which could provide a feasible way for the reform and reconstruction of the rural elderly care service system.
