The main content of this article is the analysis of chances and challenges after China enters WTO. It also points out how to use competition to seek countermeasures of the contemporary shortcomings of the entry. Polic...The main content of this article is the analysis of chances and challenges after China enters WTO. It also points out how to use competition to seek countermeasures of the contemporary shortcomings of the entry. Policies should be adjusted, multinational management should be improved, the cultivation of high-tier people should be advancing, and at the same time the new orientation of the ongoing international economic readjustment should be grasped.展开更多
This study aimed to examine the effectiveness of the Chances program,a program that was established in 2004 in order to prevent juvenile delinquency among immigrant youth in Israel.Previous research showed that immedi...This study aimed to examine the effectiveness of the Chances program,a program that was established in 2004 in order to prevent juvenile delinquency among immigrant youth in Israel.Previous research showed that immediately after the program ended,all participants stopped their delinquent behavior.The current research tested the effectiveness of the program two and a half years later and explored the risk of or immunity to recidivism among graduates of the program.A sample of 145 graduates was asked to fill out a closed questionnaire examining the effectiveness of the program through self‐report questions about recidivism.The results were significant,showing that only three of the graduates(14%of the sample)continued to commit felons,while the great majority(86%)reintegrated into normative life within the community including school,employment,and army service.Fears of disappointing their tutor were found central to the discontinuation of delinquency.The graduates also attributed other elements of the Chances program to their normative behavior and reintegration into normative society.The implications of this study demonstrate that although the Chances program was designed to treat immigrant delinquent youth,its success can be relevant for treating native‐born delinquent youth as well.展开更多
Air traffic flow management has been a major means for balancing air traffic demandand airport or airspace capacity to reduce congestion and flight delays.However,unpredictable fac-tors,such as weather and equipment m...Air traffic flow management has been a major means for balancing air traffic demandand airport or airspace capacity to reduce congestion and flight delays.However,unpredictable fac-tors,such as weather and equipment malfunctions,can cause dynamic changes in airport and sectorcapacity,resulting in significant alterations to optimized flight schedules and the calculated pre-departure slots.Therefore,taking into account capacity uncertainties is essential to create a moreresilient flight schedule.This paper addresses the flight pre-departure sequencing issue and intro-duces a capacity uncertainty model for optimizing flight schedule at the airport network level.The goal of the model is to reduce the total cost of flight delays while increasing the robustnessof the optimized schedule.A chance-constrained model is developed to address the capacity uncer-tainty of airports and sectors,and the significance of airports and sectors in the airport network isconsidered when setting the violation probability.The performance of the model is evaluated usingreal flight data by comparing them with the results of the deterministic model.The development ofthe model based on the characteristics of this special optimization mechanism can significantlyenhance its performance in addressing the pre-departure flight scheduling problem at the airportnetwork level.展开更多
The electricity-hydrogen integrated energy system(EH-IES)enables synergistic operation of electricity,heat,and hydrogen subsystems,supporting renewable energy integration and efficient multi-energy utilization in futu...The electricity-hydrogen integrated energy system(EH-IES)enables synergistic operation of electricity,heat,and hydrogen subsystems,supporting renewable energy integration and efficient multi-energy utilization in future low carbon societies.However,uncertainties from renewable energy and load variability threaten system safety and economy.Conventional chance-constrained programming(CCP)ensures reliable operation by limiting risk.However,increasing source-load uncertainties that can render CCP models infeasible and exacerbate operational risks.To address this,this paper proposes a risk-adjustable chance-constrained goal programming(RACCGP)model,integrating CCP and goal programming to balance risk and cost based on system risk assessment.An intelligent nonlinear goal programming method based on the state transition algorithm(STA)is developed,along with an improved discretized step transformation,to handle model nonlinearity and enhance computational efficiency.Experimental results show that the proposed model reduces costs while controlling risk compared to traditional CCP,and the solution method outperforms average sample sampling in efficiency and solution quality.展开更多
Today,IT security plays a crucial role in the Olympic Games.What will be the greatest IT challenges for the Beijing Olympics,and how will the organizers guarantee security during the Games?In a recent interview with B...Today,IT security plays a crucial role in the Olympic Games.What will be the greatest IT challenges for the Beijing Olympics,and how will the organizers guarantee security during the Games?In a recent interview with Beijing Review reporter Chen Ran,Patrick Adiba,Executive Vice President in charge of the Olympics and Major Events from IT company Atos Origin, talked about the latest developments in the Beijing Olympics IT project.展开更多
This paper systematically introduces and reviews a scientific exploration of reliability called the belief reliability.Beginning with the origin of reliability engineering,the problems of present theories for reliabil...This paper systematically introduces and reviews a scientific exploration of reliability called the belief reliability.Beginning with the origin of reliability engineering,the problems of present theories for reliability engineering are summarized as a query,a dilemma,and a puzzle.Then,through philosophical reflection,we introduce the theoretical solutions given by belief reliability theory,including scientific principles,basic equations,reliability science experiments,and mathematical measures.The basic methods and technologies of belief reliability,namely,belief reliability analysis,function-oriented belief reliability design,belief reliability evaluation,and several newly developed methods and technologies are sequentially elaborated and overviewed.Based on the above investigations,we summarize the significance of belief reliability theory and make some prospects about future research,aiming to promote the development of reliability science and engineering.展开更多
Crude oil scheduling optimization is an effective method to enhance the economic benefits of oil refining.But uncertainties,including uncertain demands of crude distillation units(CDUs),might make the production plans...Crude oil scheduling optimization is an effective method to enhance the economic benefits of oil refining.But uncertainties,including uncertain demands of crude distillation units(CDUs),might make the production plans made by the traditional deterministic optimization models infeasible.A data-driven Wasserstein distributionally robust chance-constrained(WDRCC)optimization approach is proposed in this paper to deal with demand uncertainty in crude oil scheduling.First,a new deterministic crude oil scheduling optimization model is developed as the basis of this approach.The Wasserstein distance is then used to build ambiguity sets from historical data to describe the possible realizations of probability distributions of uncertain demands.A cross-validation method is advanced to choose suitable radii for these ambiguity sets.The deterministic model is reformulated as a WDRCC optimization model for crude oil scheduling to guarantee the demand constraints hold with a desired high probability even in the worst situation in ambiguity sets.The proposed WDRCC model is transferred into an equivalent conditional value-at-risk representation and further derived as a mixed-integer nonlinear programming counterpart.Industrial case studies from a real-world refinery are conducted to show the effectiveness of the proposed method.Out-of-sample tests demonstrate that the solution of the WDRCC model is more robust than those of the deterministic model and the chance-constrained model.展开更多
Spatial equity in access to urban services is a significant element of sustainable urban planning.To date,a service-based index is used to measure service attractiveness,considering attractiveness as a static concept....Spatial equity in access to urban services is a significant element of sustainable urban planning.To date,a service-based index is used to measure service attractiveness,considering attractiveness as a static concept.While from the user side view,service attractiveness is a dynamic concept related to the variation of different opportunities of users to use the services and capacities.In this paper,a user-based method for measuring service attractiveness is proposed.In this approach,the attractiveness of service for a user is modeled as a function of the user's Travel Times(TT),Free Times(FTs),park size and relative positions of the user,local demanding population,and service.Then,the inequity of attractiveness of services for different users has been examined using three inequity indices including the Duration of Use(DU),Frequency of Visit(FV),and the Chance of Space Choice(CSC).The proposed method is applied to urban regional parks of Tehran municipality.Traffc Analysis Zones(TAZs)and regional parks are respectively regarded as the users and services.In addition to considering inequity of access to the first closest park,the additional cost of accessing to the other two closest parks is also considered.Results show that the proposed method leads to the exploration of the existing inequities of DU,FV,and CSC among residents in local scales,whereas in the service-based method,all users of a service are highlighted with a single value of attractiveness.Comparison of the user-based and service-based attractiveness indices show significant differences.As an example,user-based attractiveness values of about 14%and 20%of TAZs are respectively 5 and 3 square meters more than that of the service-based attractiveness index.However,the service-based method is suitable for regional-scale comparison of the inequities.Therefore,the proposed index can complement the service-based index for inequity mapping and management in varying scales.展开更多
Exchange programme offers chance to see the amazing progress China has made in all aspects Wonderful,amazing,charming!These words aptly describe my first experience in China when I visited the country to attend the 8t...Exchange programme offers chance to see the amazing progress China has made in all aspects Wonderful,amazing,charming!These words aptly describe my first experience in China when I visited the country to attend the 8th China-Africa Youth Festival,held in Beijing and then Zhejiang Province on 19-26 May.展开更多
According to the operational characteristics of the logistics networks for the third party logistics supplier （3PLS）, the forward and reverse logistics networks together for 3PLS under the uncertain environment are ...According to the operational characteristics of the logistics networks for the third party logistics supplier （3PLS）, the forward and reverse logistics networks together for 3PLS under the uncertain environment are designed. First, a fuzzy model is proposed by taking multiple customers, multiple commodities, capacitated facility location and integrated logistics facility layout into account. In the model, the fuzzy customer demands and transportation rates are illustrated by triangular fuzzy numbers. Secondly, the fuzzy model is converted into a crisp model by applying fuzzy chance constrained theory and possibility theory, and one hybrid genetic algorithm is designed for the crisp model. Finally, two different examples are designed to illustrate that the model and solution discussed are valid.展开更多
文摘The main content of this article is the analysis of chances and challenges after China enters WTO. It also points out how to use competition to seek countermeasures of the contemporary shortcomings of the entry. Policies should be adjusted, multinational management should be improved, the cultivation of high-tier people should be advancing, and at the same time the new orientation of the ongoing international economic readjustment should be grasped.
文摘This study aimed to examine the effectiveness of the Chances program,a program that was established in 2004 in order to prevent juvenile delinquency among immigrant youth in Israel.Previous research showed that immediately after the program ended,all participants stopped their delinquent behavior.The current research tested the effectiveness of the program two and a half years later and explored the risk of or immunity to recidivism among graduates of the program.A sample of 145 graduates was asked to fill out a closed questionnaire examining the effectiveness of the program through self‐report questions about recidivism.The results were significant,showing that only three of the graduates(14%of the sample)continued to commit felons,while the great majority(86%)reintegrated into normative life within the community including school,employment,and army service.Fears of disappointing their tutor were found central to the discontinuation of delinquency.The graduates also attributed other elements of the Chances program to their normative behavior and reintegration into normative society.The implications of this study demonstrate that although the Chances program was designed to treat immigrant delinquent youth,its success can be relevant for treating native‐born delinquent youth as well.
基金supported by the National Natural Science Foundation of China(Nos.U2033203,U1833126,61773203,61304190)。
文摘Air traffic flow management has been a major means for balancing air traffic demandand airport or airspace capacity to reduce congestion and flight delays.However,unpredictable fac-tors,such as weather and equipment malfunctions,can cause dynamic changes in airport and sectorcapacity,resulting in significant alterations to optimized flight schedules and the calculated pre-departure slots.Therefore,taking into account capacity uncertainties is essential to create a moreresilient flight schedule.This paper addresses the flight pre-departure sequencing issue and intro-duces a capacity uncertainty model for optimizing flight schedule at the airport network level.The goal of the model is to reduce the total cost of flight delays while increasing the robustnessof the optimized schedule.A chance-constrained model is developed to address the capacity uncer-tainty of airports and sectors,and the significance of airports and sectors in the airport network isconsidered when setting the violation probability.The performance of the model is evaluated usingreal flight data by comparing them with the results of the deterministic model.The development ofthe model based on the characteristics of this special optimization mechanism can significantlyenhance its performance in addressing the pre-departure flight scheduling problem at the airportnetwork level.
基金Project(2022YFC2904502)supported by the National Key Research and Development Program of ChinaProject(62273357)supported by the National Natural Science Foundation of China。
文摘The electricity-hydrogen integrated energy system(EH-IES)enables synergistic operation of electricity,heat,and hydrogen subsystems,supporting renewable energy integration and efficient multi-energy utilization in future low carbon societies.However,uncertainties from renewable energy and load variability threaten system safety and economy.Conventional chance-constrained programming(CCP)ensures reliable operation by limiting risk.However,increasing source-load uncertainties that can render CCP models infeasible and exacerbate operational risks.To address this,this paper proposes a risk-adjustable chance-constrained goal programming(RACCGP)model,integrating CCP and goal programming to balance risk and cost based on system risk assessment.An intelligent nonlinear goal programming method based on the state transition algorithm(STA)is developed,along with an improved discretized step transformation,to handle model nonlinearity and enhance computational efficiency.Experimental results show that the proposed model reduces costs while controlling risk compared to traditional CCP,and the solution method outperforms average sample sampling in efficiency and solution quality.
文摘Today,IT security plays a crucial role in the Olympic Games.What will be the greatest IT challenges for the Beijing Olympics,and how will the organizers guarantee security during the Games?In a recent interview with Beijing Review reporter Chen Ran,Patrick Adiba,Executive Vice President in charge of the Olympics and Major Events from IT company Atos Origin, talked about the latest developments in the Beijing Olympics IT project.
基金supported by the National Natural Science Foundation of China(62073009,52775020,72201013)the China Postdoctoral Science Foundation(2022M710314)the Funding of Science&Technology on Reliability&Environmental Engineering Laboratory(6142004210102)。
文摘This paper systematically introduces and reviews a scientific exploration of reliability called the belief reliability.Beginning with the origin of reliability engineering,the problems of present theories for reliability engineering are summarized as a query,a dilemma,and a puzzle.Then,through philosophical reflection,we introduce the theoretical solutions given by belief reliability theory,including scientific principles,basic equations,reliability science experiments,and mathematical measures.The basic methods and technologies of belief reliability,namely,belief reliability analysis,function-oriented belief reliability design,belief reliability evaluation,and several newly developed methods and technologies are sequentially elaborated and overviewed.Based on the above investigations,we summarize the significance of belief reliability theory and make some prospects about future research,aiming to promote the development of reliability science and engineering.
基金the supports from National Natural Science Foundation of China(61988101,62073142,22178103)National Natural Science Fund for Distinguished Young Scholars(61925305)International(Regional)Cooperation and Exchange Project(61720106008)。
文摘Crude oil scheduling optimization is an effective method to enhance the economic benefits of oil refining.But uncertainties,including uncertain demands of crude distillation units(CDUs),might make the production plans made by the traditional deterministic optimization models infeasible.A data-driven Wasserstein distributionally robust chance-constrained(WDRCC)optimization approach is proposed in this paper to deal with demand uncertainty in crude oil scheduling.First,a new deterministic crude oil scheduling optimization model is developed as the basis of this approach.The Wasserstein distance is then used to build ambiguity sets from historical data to describe the possible realizations of probability distributions of uncertain demands.A cross-validation method is advanced to choose suitable radii for these ambiguity sets.The deterministic model is reformulated as a WDRCC optimization model for crude oil scheduling to guarantee the demand constraints hold with a desired high probability even in the worst situation in ambiguity sets.The proposed WDRCC model is transferred into an equivalent conditional value-at-risk representation and further derived as a mixed-integer nonlinear programming counterpart.Industrial case studies from a real-world refinery are conducted to show the effectiveness of the proposed method.Out-of-sample tests demonstrate that the solution of the WDRCC model is more robust than those of the deterministic model and the chance-constrained model.
文摘Spatial equity in access to urban services is a significant element of sustainable urban planning.To date,a service-based index is used to measure service attractiveness,considering attractiveness as a static concept.While from the user side view,service attractiveness is a dynamic concept related to the variation of different opportunities of users to use the services and capacities.In this paper,a user-based method for measuring service attractiveness is proposed.In this approach,the attractiveness of service for a user is modeled as a function of the user's Travel Times(TT),Free Times(FTs),park size and relative positions of the user,local demanding population,and service.Then,the inequity of attractiveness of services for different users has been examined using three inequity indices including the Duration of Use(DU),Frequency of Visit(FV),and the Chance of Space Choice(CSC).The proposed method is applied to urban regional parks of Tehran municipality.Traffc Analysis Zones(TAZs)and regional parks are respectively regarded as the users and services.In addition to considering inequity of access to the first closest park,the additional cost of accessing to the other two closest parks is also considered.Results show that the proposed method leads to the exploration of the existing inequities of DU,FV,and CSC among residents in local scales,whereas in the service-based method,all users of a service are highlighted with a single value of attractiveness.Comparison of the user-based and service-based attractiveness indices show significant differences.As an example,user-based attractiveness values of about 14%and 20%of TAZs are respectively 5 and 3 square meters more than that of the service-based attractiveness index.However,the service-based method is suitable for regional-scale comparison of the inequities.Therefore,the proposed index can complement the service-based index for inequity mapping and management in varying scales.
文摘Exchange programme offers chance to see the amazing progress China has made in all aspects Wonderful,amazing,charming!These words aptly describe my first experience in China when I visited the country to attend the 8th China-Africa Youth Festival,held in Beijing and then Zhejiang Province on 19-26 May.
文摘According to the operational characteristics of the logistics networks for the third party logistics supplier （3PLS）, the forward and reverse logistics networks together for 3PLS under the uncertain environment are designed. First, a fuzzy model is proposed by taking multiple customers, multiple commodities, capacitated facility location and integrated logistics facility layout into account. In the model, the fuzzy customer demands and transportation rates are illustrated by triangular fuzzy numbers. Secondly, the fuzzy model is converted into a crisp model by applying fuzzy chance constrained theory and possibility theory, and one hybrid genetic algorithm is designed for the crisp model. Finally, two different examples are designed to illustrate that the model and solution discussed are valid.
