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
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
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
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
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 study proposes a two-stage photovoltaic(PV)voltage control strategy for centralized control that ignores short-term load fluctuations.In the first stage,a deterministic power flow model optimizes the 15-minute ac...This study proposes a two-stage photovoltaic(PV)voltage control strategy for centralized control that ignores short-term load fluctuations.In the first stage,a deterministic power flow model optimizes the 15-minute active cycle of the inverter and reactive outputs to reduce network loss and light rejection.In the second stage,the local control stabilizes the fluctuations and tracks the system state of the first stage.The uncertain interval model establishes a chance constraint model for the inverter voltage-reactive power local control.Second-order cone optimization and sensitivity theories were employed to solve the models.The effectiveness of the model was confirmed using a modified IEEE 33 bus example.The intraday control outcome for distributed power generation considering the effects of fluctuation uncertainty,PV penetration rate,and inverter capacity is analyzed.展开更多
Because of the randomness of wind power and photovoltaic(PV)output of new energy bases,the problem of peak regulation capability and voltage stability of ultra-high voltage direct current(UHVDC)transmission lines,we p...Because of the randomness of wind power and photovoltaic(PV)output of new energy bases,the problem of peak regulation capability and voltage stability of ultra-high voltage direct current(UHVDC)transmission lines,we proposed an optimum allocation method of installed capacity of the solar-thermal power station based on chance constrained programming in this work.Firstly,we established the uncertainty model of wind power and PV based on the chance constrained planning theory.Then we used the K-medoids clusteringmethod to cluster the scenarios considering the actual operation scenarios throughout the year.Secondly,we established the optimal configuration model based on the objective function of the strongest transient voltage stability and the lowest overall cost of operation.Finally,by quantitative analysis of actual wind power and photovoltaic new energy base,this work verified the feasibility of the proposed method.As a result of the simulations,we found that using the optimal configuration method of solar-thermal power stations could ensure an accurate allocation of installed capacity.When the installed capacity of the solar-thermal power station is 1×106 kW,the transient voltage recovery index(TVRI)is 0.359,which has a strong voltage support capacity for the system.Based on the results of this work,the optimal configuration of the installed capacity of the solar-thermal power plant can improve peak shaving performance,transient voltage support capability,and new energy consumption while satisfying the Direct Current(DC)outgoing transmission premise.展开更多
Introduction: Online gambling is becoming increasingly popular worldwide. With its well-crafted visual and audio marketing, it is attracting more and more young people in Africa, where problems linked to employment an...Introduction: Online gambling is becoming increasingly popular worldwide. With its well-crafted visual and audio marketing, it is attracting more and more young people in Africa, where problems linked to employment and poverty are undermining youth. The consequences of gaming-related practices for health in general, and mental health in particular, are not negligible. The aim of this study was to measure the extent of the phenomenon within an urban community in Benin. Methods: Descriptive cross-sectional study with analytical aim conducted in the general population of Parakou, northern Benin, from December 2021 to November 2022. A self-administered questionnaire incorporating DSM 5 criteria for pathological gambling was used to collect data. Results: A total of 576 subjects divided into 30 clusters of 19 to 20 individuals consented to participate in the study. The proportion of gamblers was 30.56%. The prevalence of pathological gambling calculated according to DSM 5 criteria was 24.65% [21.31% - 28.33%] in the general population. The prevalence of severe pathological gambling was estimated at 8.16% [5.96% - 10.44%] in the general population. The prevalence of anxiety was 28.30% ([24.62% - 31.98%]), compared with 15.10% ([12.18% - 18.02%]) for depression. Factors with a significant association with pathological gambling were: age, access to online gambling, access to video games, exposure to gambling advertisement, having gambling friends, debt accumulation. A statistically significant link was also found between pathological gambling and anxiety/depression. Conclusion: The reality of pathological gambling in northern Benin calls for effective preventive action among vulnerable groups at national level, involving various actors at different levels.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.
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.
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 China National Natural Science Foundation(52177082)China National Key R&D Program(2020YFC0827001)Science and Technology Project of Jilin Electric Power Co.,Ltd(2020JBGS-03).
文摘This study proposes a two-stage photovoltaic(PV)voltage control strategy for centralized control that ignores short-term load fluctuations.In the first stage,a deterministic power flow model optimizes the 15-minute active cycle of the inverter and reactive outputs to reduce network loss and light rejection.In the second stage,the local control stabilizes the fluctuations and tracks the system state of the first stage.The uncertain interval model establishes a chance constraint model for the inverter voltage-reactive power local control.Second-order cone optimization and sensitivity theories were employed to solve the models.The effectiveness of the model was confirmed using a modified IEEE 33 bus example.The intraday control outcome for distributed power generation considering the effects of fluctuation uncertainty,PV penetration rate,and inverter capacity is analyzed.
基金funded by Major Science and Technology Projects in Gansu Province(19ZD2GA003).
文摘Because of the randomness of wind power and photovoltaic(PV)output of new energy bases,the problem of peak regulation capability and voltage stability of ultra-high voltage direct current(UHVDC)transmission lines,we proposed an optimum allocation method of installed capacity of the solar-thermal power station based on chance constrained programming in this work.Firstly,we established the uncertainty model of wind power and PV based on the chance constrained planning theory.Then we used the K-medoids clusteringmethod to cluster the scenarios considering the actual operation scenarios throughout the year.Secondly,we established the optimal configuration model based on the objective function of the strongest transient voltage stability and the lowest overall cost of operation.Finally,by quantitative analysis of actual wind power and photovoltaic new energy base,this work verified the feasibility of the proposed method.As a result of the simulations,we found that using the optimal configuration method of solar-thermal power stations could ensure an accurate allocation of installed capacity.When the installed capacity of the solar-thermal power station is 1×106 kW,the transient voltage recovery index(TVRI)is 0.359,which has a strong voltage support capacity for the system.Based on the results of this work,the optimal configuration of the installed capacity of the solar-thermal power plant can improve peak shaving performance,transient voltage support capability,and new energy consumption while satisfying the Direct Current(DC)outgoing transmission premise.
文摘Introduction: Online gambling is becoming increasingly popular worldwide. With its well-crafted visual and audio marketing, it is attracting more and more young people in Africa, where problems linked to employment and poverty are undermining youth. The consequences of gaming-related practices for health in general, and mental health in particular, are not negligible. The aim of this study was to measure the extent of the phenomenon within an urban community in Benin. Methods: Descriptive cross-sectional study with analytical aim conducted in the general population of Parakou, northern Benin, from December 2021 to November 2022. A self-administered questionnaire incorporating DSM 5 criteria for pathological gambling was used to collect data. Results: A total of 576 subjects divided into 30 clusters of 19 to 20 individuals consented to participate in the study. The proportion of gamblers was 30.56%. The prevalence of pathological gambling calculated according to DSM 5 criteria was 24.65% [21.31% - 28.33%] in the general population. The prevalence of severe pathological gambling was estimated at 8.16% [5.96% - 10.44%] in the general population. The prevalence of anxiety was 28.30% ([24.62% - 31.98%]), compared with 15.10% ([12.18% - 18.02%]) for depression. Factors with a significant association with pathological gambling were: age, access to online gambling, access to video games, exposure to gambling advertisement, having gambling friends, debt accumulation. A statistically significant link was also found between pathological gambling and anxiety/depression. Conclusion: The reality of pathological gambling in northern Benin calls for effective preventive action among vulnerable groups at national level, involving various actors at different levels.