In the framework of an overlapping generations model, forward-looking monetary policy roles and backward-looking monetary policy rules were investigated. It is shown that the monetary steady state is more likely to be...In the framework of an overlapping generations model, forward-looking monetary policy roles and backward-looking monetary policy rules were investigated. It is shown that the monetary steady state is more likely to be indeterminate under an active forwardlooking rule than under the corresponding backward-looking rule. It is also shown that backward-looking roles can render the monetary steady state unstable.展开更多
Chinese government has initiated many preferential policies for supporting the circular economy, including the industry of municipal solid waste (MSW) power generation. This paper collects relevant policies for Chin...Chinese government has initiated many preferential policies for supporting the circular economy, including the industry of municipal solid waste (MSW) power generation. This paper collects relevant policies for China's MSW power generation. It also analyzes the overall environment of policies for the MSW power generation from three aspects---the basic principles for China to develop MSW power generation, the operating mechanism and the specific preferential policies. The analysis establishes foundation for further research toward policy integration.展开更多
Since renewable energy sources are growing in importance, how well they can penetrate the energy market for power generation will be a very important factor in the role the coal industry will play in the future. This ...Since renewable energy sources are growing in importance, how well they can penetrate the energy market for power generation will be a very important factor in the role the coal industry will play in the future. This paper examined the displacement of coal power plant capacity from 2010 to 2050 by renewables with respect to three drivers assumed under various conditions: the American Recovery and Reinvestment Act (ARRA), Greenhouse Gas (GItG) policy, and varying plant capital cost cases. The results by 2050 illustrate that renewable market penetration captures anywhere from 1.9% to 6.4% of potential coal power generation capacity additions. Renewable power generation capacity additions is expected to outpace coal power plant additions by 89% with respect to ARRA in 2050, however with no GHG policy coal power generation capacity build-outs will outpace renewables by as high as 809%. Finally, coal power generation is still projected to be the largest single energy source contributor to the electricity market making up 28.0% of total available capacity, while renewables are expected to only make up 16.3% of total available capacity.展开更多
This paper presents a new algorithm for generation of attack signatures based on sequence alignment. The algorithm is composed of two parts: a local alignment algorithm-GASBSLA (Generation of Attack Signatures Based o...This paper presents a new algorithm for generation of attack signatures based on sequence alignment. The algorithm is composed of two parts: a local alignment algorithm-GASBSLA (Generation of Attack Signatures Based on Sequence Local Alignment) and a multi-sequence alignment algorithm-TGMSA (Tri-stage Gradual Multi-Sequence Alignment). With the inspiration of sequence alignment used in Bioinformatics, GASBSLA replaces global alignment and constant weight penalty model by local alignment and affine penalty model to improve the generality of attack signatures. TGMSA presents a new pruning policy to make the algorithm more insensitive to noises in the generation of attack signatures. In this paper, GASBSLA and TGMSA are described in detail and validated by experiments.展开更多
In response to the challenges of generating Attribute-Based Access Control(ABAC)policies,this paper proposes a deep learning-based method to automatically generate ABAC policies from natural language documents.This me...In response to the challenges of generating Attribute-Based Access Control(ABAC)policies,this paper proposes a deep learning-based method to automatically generate ABAC policies from natural language documents.This method is aimed at organizations such as companies and schools that are transitioning from traditional access control models to the ABAC model.The manual retrieval and analysis involved in this transition are inefficient,prone to errors,and costly.Most organizations have high-level specifications defined for security policies that include a set of access control policies,which often exist in the form of natural language documents.Utilizing this rich source of information,our method effectively identifies and extracts the necessary attributes and rules for access control from natural language documents,thereby constructing and optimizing access control policies.This work transforms the problem of policy automation generation into two tasks:extraction of access control statements andmining of access control attributes.First,the Chat General Language Model(ChatGLM)isemployed to extract access control-related statements from a wide range of natural language documents by constructing unique prompts and leveraging the model’s In-Context Learning to contextualize the statements.Then,the Iterated Dilated-Convolutions-Conditional Random Field(ID-CNN-CRF)model is used to annotate access control attributes within these extracted statements,including subject attributes,object attributes,and action attributes,thus reassembling new access control policies.Experimental results show that our method,compared to baseline methods,achieved the highest F1 score of 0.961,confirming the model’s effectiveness and accuracy.展开更多
In China, the national policies on employment generation of migrant workers have an important role in guiding. The employment satisfaction generation of migrant workers, the employment scale, employment quality were a...In China, the national policies on employment generation of migrant workers have an important role in guiding. The employment satisfaction generation of migrant workers, the employment scale, employment quality were all studied via research and statistics, which were analysing to result in the role of national policies to promote employment of the new generation of migrant workers, and the various factors of the impact of the new generation of rural migrant workers in recent years. In this study, the two generations are treated differently according to their characteristics, which results in conclusions that can fully display the current generation problems in the process of employment Therefore, the current systematic research and exploration about the employment problem has very important significance.展开更多
Despite the advances in automated vulnerability detection approaches,security vulnerabilities caused by design flaws in software systems are continuously appearing in real-world systems.Such security design flaws can ...Despite the advances in automated vulnerability detection approaches,security vulnerabilities caused by design flaws in software systems are continuously appearing in real-world systems.Such security design flaws can bring unrestricted and misimplemented behaviors of a system and can lead to fatal vulnerabilities such as remote code execution or sensitive data leakage.Therefore,it is an essential task to discover unrestricted and misimplemented behaviors of a system.However,it is a daunting task for security experts to discover such vulnerabilities in advance because it is timeconsuming and error-prone to analyze the whole code in detail.Also,most of the existing vulnerability detection approaches still focus on detecting memory corruption bugs because these bugs are the dominant root cause of software vulnerabilities.This paper proposes SMINER,a novel approach that discovers vulnerabilities caused by unrestricted and misimplemented behaviors.SMINER first collects unit test cases for the target system from the official repository.Next,preprocess the collected code fragments.SMINER uses pre-processed data to show the security policies that can occur on the target system and creates a test case for security policy testing.To demonstrate the effectiveness of SMINER,this paper evaluates SMINER against Robot Operating System(ROS),a real-world system used for intelligent robots in Amazon and controlling satellites in National Aeronautics and Space Administration(NASA).From the evaluation,we discovered two real-world vulnerabilities in ROS.展开更多
A small but growing body of literature uses overlapping generations (OLG) models to study environmental policy for long-lived problems such as climate change. An OLG model, unlike the infinitely lived representative...A small but growing body of literature uses overlapping generations (OLG) models to study environmental policy for long-lived problems such as climate change. An OLG model, unlike the infinitely lived representative agent model, dis- tinguishes between impatience with respect to one's own future utility, and attitudes toward successors' utility. I discuss the problem of time inconsistency, the role of Markov perfection, and show that a class of OLG models can be studied using me- thods developed to analyze models of non-constant discounting. An example illu- strates the techniques and determines the conditions under which, in equilibrium, there is under-investment or over-investment in natural capital.展开更多
People's livelihood in several Himalayan regions largely depends on collection,use,and trade of medicinal plants.Traditional use is generally not a problem,but commercial gathering of selected species to meet incr...People's livelihood in several Himalayan regions largely depends on collection,use,and trade of medicinal plants.Traditional use is generally not a problem,but commercial gathering of selected species to meet increasing national and international demand can result in over-exploitation.Sustainable management of medicinal plants requires a clear understanding of the respective roles,responsibilities and viewpoints of the various stakeholders involved.Through personal interviews and group discussions,this study aimed at investigating the views of two stakeholder groups on use,trade and conservation of medicinal plants in the Rasuwa district of Nepal.Local people and district and national organizations agreed that medicinal plants are collected for a combination of commercial and personal uses.Perceptions on market availability differed significantly:100 % of the respondents from district and national organizations saw markets as easily available,against only 36 % for local people.This could explain why medicinal plants were perceived by local people to contribute less to income generation than to livelihood improvement.Different viewpoints were also expressed concerning the status of medicinal plants in the district:81 % of the respondents from district and national organizationsconsidered that medicinal plants were threatened,compared to only 28 % for local people.Despite this disparity,both stakeholder groups agreed upon potential threats to medicinal plants:over-harvesting;habitat loss due to land-use change and deforestation;and over-grazing by livestock.Several challenges were identified regarding sustainable management of medicinal plants,such as ambiguous policies;lack of resources,information and infrastructures;habitat degradation;and over-exploitation.Despite these challenges,respondents agreed that the medicinal plants sector offers huge opportunities in the Rasuwa district,given resource availability,community awareness and motivation,and the priority given to the sector by governments and other agencies.Proper collaboration,communication and coordination among stakeholders are needed to grab these opportunities.展开更多
In 1982 China endorsed the one-child policy as one of the country’s national policies.The policy came at a special historical moment when rapid population growth in preceding decades posed increasing challenges to th...In 1982 China endorsed the one-child policy as one of the country’s national policies.The policy came at a special historical moment when rapid population growth in preceding decades posed increasing challenges to the standards of people’s living,education,health care and employment,makingit extremelydifficult forthe coun-try to rid itself of poverty in the foreseeable future.A mong developing countries with huge populations,China was the only one to retain a low birth rate during part of展开更多
Proposals to change China’s family planning policy were put forward during the recent sessions of the National People’s Congress (NPC) and the Chinese People’s Political Consultative Conference (CPPCC) by a number ...Proposals to change China’s family planning policy were put forward during the recent sessions of the National People’s Congress (NPC) and the Chinese People’s Political Consultative Conference (CPPCC) by a number of NPC deputies and展开更多
Renewable energy generation,as part of the global effort to mitigate climate change,will play a central role in reducing greenhouse gas emissions and achieving China's goal of carbon emissions peak before 2030 and...Renewable energy generation,as part of the global effort to mitigate climate change,will play a central role in reducing greenhouse gas emissions and achieving China's goal of carbon emissions peak before 2030 and carbon neutral before 2060.However,the impact of carbon quota auctions on renewable energy generation has not been sufficiently discussed.The main purpose of this study is to investigate whether China can rely on quota auctions to increase renewable energy generation in the short term,and to demonstrate which is more effective in promoting renewable energy development,policy enforcement or auction constraints?The improved neo-trans-log production model,the multiobjective linear programming model and the dispatch heuristic were used to predict additional emission reduction cost,optimized power mix with different auctioning rates,with economic development,technological progress and the unique characteristics of China's power generation industry being taken into consideration.The results show that the auctioning rate will have little influence on the optimized energy production structure,especially on the share of renewable energy resources;when the total on-grid electricity generation ranges from 7625 to 7926 billion kW h and the auctioning rate ranges from 0% to 5%,policy enforcement will influence the generation of renewable energy to a greater extent than auctioning in the near future.展开更多
This article describes some dynamic aspects on dynastic utility incorporating two-sided altruism with an OLG setting. The special case is analyzed where the weights of two-sided altruism are dynamically inconsistent. ...This article describes some dynamic aspects on dynastic utility incorporating two-sided altruism with an OLG setting. The special case is analyzed where the weights of two-sided altruism are dynamically inconsistent. The Bellman equation for two-sided altruism proves to be reduced to one-sided dynamic problem, but the effective discount factor is different only in the current generation. It is shown that a contraction mapping result of value function cannot be achieved in general, and that there can locally exist an infinite number of self-consistent policy functions of the class C" with distinct steady states (indeterminacy of self-consistent, differentiable policy functions).展开更多
During the 11th Five-year Plan (2006-2010), the total fertility rate of the mainland of China was 1.481 and was stable with a slight decline, exhibiting a spatial pattern of moderately low fertility in the central a...During the 11th Five-year Plan (2006-2010), the total fertility rate of the mainland of China was 1.481 and was stable with a slight decline, exhibiting a spatial pattern of moderately low fertility in the central and western regions, very low fertility in the east and extremely low fertility in the northeast. Except for a rebound in a few provinces and regions with extremely low fertility rates, the ratio of actual fertility rates to policy fertility rates is still falling. The reduced fertility rate is mainly driven by development, notably the proportion of the total population represented by the exuberantly fertile women of child-bearing age and their greater urbanization, growing level of non-agricultural employment and outflow from rural areas, as well as the assimilative effect of urban production, lifestyles and culturalconcepts upon the agricultural population. Development has catalyzed an irreversible trend of declining fertility; existing fertility policy has proven insufficient to keep fertility rates stable at reasonably low levels. Policy-based rebounds may emerge in urban areas and the east and northeast, where family planning policy has been better implemented; on the other hand, a non-policy-based rebound may have been released. In the central and western rural areas, multiple births occur on average among only 4.12 percent of the younger generation of women. As fertility policy is adjusted and improved, fertility rebounds in transitional fertility policy adjustment can be effectively regulated through a gradual strategy which will not provoke a sharp rebound. The time is ripe for China to conduct a nationally unified adjustment of the existing fertility policy.展开更多
The two-child policy was officially proclaimed in the Guideline of the 13th Five-Year Plan and approved in March 2016.This article provides a detailed analysis of the Chinese demographic structure characterised by age...The two-child policy was officially proclaimed in the Guideline of the 13th Five-Year Plan and approved in March 2016.This article provides a detailed analysis of the Chinese demographic structure characterised by ageing with sub-replacement fertility.It argues that the universal two-child policy is timely and necessary for the New Normal economy.The policy has significance in relieving socio-economic pressure and promoting economic growth,for which it is not only a necessary premise but also a sufficient condition.Having reviewed the evolution of the demographic transition theory,this research undertakes a comparative analysis of different stages of demographic transition in different regions across the world.It further investigates the three stages of successful demographic transition in China.The universally adopted two-child policy,as it meets the requirements of demographic transition,is also inevitable for socio-economic development.展开更多
Due to the significance and value in human-computer interaction and natural language processing,task-oriented dialog systems are attracting more and more attention in both academic and industrial communities.In this p...Due to the significance and value in human-computer interaction and natural language processing,task-oriented dialog systems are attracting more and more attention in both academic and industrial communities.In this paper,we survey recent advances and challenges in task-oriented dialog systems.We also discuss three critical topics for task-oriented dialog systems:(1)improving data efficiency to facilitate dialog modeling in low-resource settings,(2)modeling multi-turn dynamics for dialog policy learning to achieve better task-completion performance,and(3)integrating domain ontology knowledge into the dialog model.Besides,we review the recent progresses in dialog evaluation and some widely-used corpora.We believe that this survey,though incomplete,can shed a light on future research in task-oriented dialog systems.展开更多
This paper examines the motivations of parent-child co-residence behavior in China using data from the China Health and Retirement Longitudinal Study.We test three possible motives:social norms,self-interest and altru...This paper examines the motivations of parent-child co-residence behavior in China using data from the China Health and Retirement Longitudinal Study.We test three possible motives:social norms,self-interest and altruism.We find that social norms play an important role in household co-residence behavior,showing that the belief that"sons take care of parents"is strong,and children in different birth orders take different responsibilities.Taking the one-child policy as a natural experiment,we compared co-residence behavior between only-child and multi-child families.This allowed us to test whether children in multi-child families with wealthier parents more often coreside in order to compete for a bequest.We find that parents'wealth is more appealing to children in multi-child families.The results support the life cycle theory that coresidence decisions are motivated by self-interest.We also find some evidence of altruism when parents and children make co-residence decisions.These findings provide some insights for designing future elder-support policies in China.展开更多
This work proposes a reinforcement learning(RL)approach to tackle the control problem of branch overload relief in large power systems.Accordingly,a control agent is trained to change generators'real power output ...This work proposes a reinforcement learning(RL)approach to tackle the control problem of branch overload relief in large power systems.Accordingly,a control agent is trained to change generators'real power output in order to relieve the stressed branches.For large power systems,this control problem becomes one whose decision space(i.e.,the action space)is both highly-dimensioned and continuous.This makes it extremely difficult to have successful training for RL-based agents.To improve the effectiveness,a data-driven and model-based hybrid approach is proposed to optimize the control by combining RL-agent actions and generator shifting factor-driven actions.Accordingly,with the proposed approach the RL-agent successfully trains on large power systems.The proposed design is tested on both the IEEE 118-bus testing system and a 2749-bus real system.The obtained results show that the proposed hybrid approach outperforms the data-driven training approach.展开更多
基金Project supported by National Natural Science Foundation of China (Grant No. 70071012)
文摘In the framework of an overlapping generations model, forward-looking monetary policy roles and backward-looking monetary policy rules were investigated. It is shown that the monetary steady state is more likely to be indeterminate under an active forwardlooking rule than under the corresponding backward-looking rule. It is also shown that backward-looking roles can render the monetary steady state unstable.
文摘Chinese government has initiated many preferential policies for supporting the circular economy, including the industry of municipal solid waste (MSW) power generation. This paper collects relevant policies for China's MSW power generation. It also analyzes the overall environment of policies for the MSW power generation from three aspects---the basic principles for China to develop MSW power generation, the operating mechanism and the specific preferential policies. The analysis establishes foundation for further research toward policy integration.
文摘Since renewable energy sources are growing in importance, how well they can penetrate the energy market for power generation will be a very important factor in the role the coal industry will play in the future. This paper examined the displacement of coal power plant capacity from 2010 to 2050 by renewables with respect to three drivers assumed under various conditions: the American Recovery and Reinvestment Act (ARRA), Greenhouse Gas (GItG) policy, and varying plant capital cost cases. The results by 2050 illustrate that renewable market penetration captures anywhere from 1.9% to 6.4% of potential coal power generation capacity additions. Renewable power generation capacity additions is expected to outpace coal power plant additions by 89% with respect to ARRA in 2050, however with no GHG policy coal power generation capacity build-outs will outpace renewables by as high as 809%. Finally, coal power generation is still projected to be the largest single energy source contributor to the electricity market making up 28.0% of total available capacity, while renewables are expected to only make up 16.3% of total available capacity.
文摘This paper presents a new algorithm for generation of attack signatures based on sequence alignment. The algorithm is composed of two parts: a local alignment algorithm-GASBSLA (Generation of Attack Signatures Based on Sequence Local Alignment) and a multi-sequence alignment algorithm-TGMSA (Tri-stage Gradual Multi-Sequence Alignment). With the inspiration of sequence alignment used in Bioinformatics, GASBSLA replaces global alignment and constant weight penalty model by local alignment and affine penalty model to improve the generality of attack signatures. TGMSA presents a new pruning policy to make the algorithm more insensitive to noises in the generation of attack signatures. In this paper, GASBSLA and TGMSA are described in detail and validated by experiments.
基金supported by the National Natural Science Foundation of China Project(No.62302540),please visit their website at https://www.nsfc.gov.cn/(accessed on 18 June 2024)The Open Foundation of Henan Key Laboratory of Cyberspace Situation Awareness(No.HNTS2022020),Further details can be found at http://xt.hnkjt.gov.cn/data/pingtai/(accessed on 18 June 2024)Natural Science Foundation of Henan Province Youth Science Fund Project(No.232300420422),you can visit https://kjt.henan.gov.cn/2022/09-02/2599082.html(accessed on 18 June 2024).
文摘In response to the challenges of generating Attribute-Based Access Control(ABAC)policies,this paper proposes a deep learning-based method to automatically generate ABAC policies from natural language documents.This method is aimed at organizations such as companies and schools that are transitioning from traditional access control models to the ABAC model.The manual retrieval and analysis involved in this transition are inefficient,prone to errors,and costly.Most organizations have high-level specifications defined for security policies that include a set of access control policies,which often exist in the form of natural language documents.Utilizing this rich source of information,our method effectively identifies and extracts the necessary attributes and rules for access control from natural language documents,thereby constructing and optimizing access control policies.This work transforms the problem of policy automation generation into two tasks:extraction of access control statements andmining of access control attributes.First,the Chat General Language Model(ChatGLM)isemployed to extract access control-related statements from a wide range of natural language documents by constructing unique prompts and leveraging the model’s In-Context Learning to contextualize the statements.Then,the Iterated Dilated-Convolutions-Conditional Random Field(ID-CNN-CRF)model is used to annotate access control attributes within these extracted statements,including subject attributes,object attributes,and action attributes,thus reassembling new access control policies.Experimental results show that our method,compared to baseline methods,achieved the highest F1 score of 0.961,confirming the model’s effectiveness and accuracy.
文摘In China, the national policies on employment generation of migrant workers have an important role in guiding. The employment satisfaction generation of migrant workers, the employment scale, employment quality were all studied via research and statistics, which were analysing to result in the role of national policies to promote employment of the new generation of migrant workers, and the various factors of the impact of the new generation of rural migrant workers in recent years. In this study, the two generations are treated differently according to their characteristics, which results in conclusions that can fully display the current generation problems in the process of employment Therefore, the current systematic research and exploration about the employment problem has very important significance.
基金This work was supported in part by the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(MSIT)Future Planning under Grant NRF-2020R1A2C2014336 and Grant NRF-2021R1A4A1029650.
文摘Despite the advances in automated vulnerability detection approaches,security vulnerabilities caused by design flaws in software systems are continuously appearing in real-world systems.Such security design flaws can bring unrestricted and misimplemented behaviors of a system and can lead to fatal vulnerabilities such as remote code execution or sensitive data leakage.Therefore,it is an essential task to discover unrestricted and misimplemented behaviors of a system.However,it is a daunting task for security experts to discover such vulnerabilities in advance because it is timeconsuming and error-prone to analyze the whole code in detail.Also,most of the existing vulnerability detection approaches still focus on detecting memory corruption bugs because these bugs are the dominant root cause of software vulnerabilities.This paper proposes SMINER,a novel approach that discovers vulnerabilities caused by unrestricted and misimplemented behaviors.SMINER first collects unit test cases for the target system from the official repository.Next,preprocess the collected code fragments.SMINER uses pre-processed data to show the security policies that can occur on the target system and creates a test case for security policy testing.To demonstrate the effectiveness of SMINER,this paper evaluates SMINER against Robot Operating System(ROS),a real-world system used for intelligent robots in Amazon and controlling satellites in National Aeronautics and Space Administration(NASA).From the evaluation,we discovered two real-world vulnerabilities in ROS.
文摘A small but growing body of literature uses overlapping generations (OLG) models to study environmental policy for long-lived problems such as climate change. An OLG model, unlike the infinitely lived representative agent model, dis- tinguishes between impatience with respect to one's own future utility, and attitudes toward successors' utility. I discuss the problem of time inconsistency, the role of Markov perfection, and show that a class of OLG models can be studied using me- thods developed to analyze models of non-constant discounting. An example illu- strates the techniques and determines the conditions under which, in equilibrium, there is under-investment or over-investment in natural capital.
文摘People's livelihood in several Himalayan regions largely depends on collection,use,and trade of medicinal plants.Traditional use is generally not a problem,but commercial gathering of selected species to meet increasing national and international demand can result in over-exploitation.Sustainable management of medicinal plants requires a clear understanding of the respective roles,responsibilities and viewpoints of the various stakeholders involved.Through personal interviews and group discussions,this study aimed at investigating the views of two stakeholder groups on use,trade and conservation of medicinal plants in the Rasuwa district of Nepal.Local people and district and national organizations agreed that medicinal plants are collected for a combination of commercial and personal uses.Perceptions on market availability differed significantly:100 % of the respondents from district and national organizations saw markets as easily available,against only 36 % for local people.This could explain why medicinal plants were perceived by local people to contribute less to income generation than to livelihood improvement.Different viewpoints were also expressed concerning the status of medicinal plants in the district:81 % of the respondents from district and national organizationsconsidered that medicinal plants were threatened,compared to only 28 % for local people.Despite this disparity,both stakeholder groups agreed upon potential threats to medicinal plants:over-harvesting;habitat loss due to land-use change and deforestation;and over-grazing by livestock.Several challenges were identified regarding sustainable management of medicinal plants,such as ambiguous policies;lack of resources,information and infrastructures;habitat degradation;and over-exploitation.Despite these challenges,respondents agreed that the medicinal plants sector offers huge opportunities in the Rasuwa district,given resource availability,community awareness and motivation,and the priority given to the sector by governments and other agencies.Proper collaboration,communication and coordination among stakeholders are needed to grab these opportunities.
文摘In 1982 China endorsed the one-child policy as one of the country’s national policies.The policy came at a special historical moment when rapid population growth in preceding decades posed increasing challenges to the standards of people’s living,education,health care and employment,makingit extremelydifficult forthe coun-try to rid itself of poverty in the foreseeable future.A mong developing countries with huge populations,China was the only one to retain a low birth rate during part of
文摘Proposals to change China’s family planning policy were put forward during the recent sessions of the National People’s Congress (NPC) and the Chinese People’s Political Consultative Conference (CPPCC) by a number of NPC deputies and
基金This research was supported by the Natiorml Natural Scicnce Foundation of China(71673086).
文摘Renewable energy generation,as part of the global effort to mitigate climate change,will play a central role in reducing greenhouse gas emissions and achieving China's goal of carbon emissions peak before 2030 and carbon neutral before 2060.However,the impact of carbon quota auctions on renewable energy generation has not been sufficiently discussed.The main purpose of this study is to investigate whether China can rely on quota auctions to increase renewable energy generation in the short term,and to demonstrate which is more effective in promoting renewable energy development,policy enforcement or auction constraints?The improved neo-trans-log production model,the multiobjective linear programming model and the dispatch heuristic were used to predict additional emission reduction cost,optimized power mix with different auctioning rates,with economic development,technological progress and the unique characteristics of China's power generation industry being taken into consideration.The results show that the auctioning rate will have little influence on the optimized energy production structure,especially on the share of renewable energy resources;when the total on-grid electricity generation ranges from 7625 to 7926 billion kW h and the auctioning rate ranges from 0% to 5%,policy enforcement will influence the generation of renewable energy to a greater extent than auctioning in the near future.
文摘This article describes some dynamic aspects on dynastic utility incorporating two-sided altruism with an OLG setting. The special case is analyzed where the weights of two-sided altruism are dynamically inconsistent. The Bellman equation for two-sided altruism proves to be reduced to one-sided dynamic problem, but the effective discount factor is different only in the current generation. It is shown that a contraction mapping result of value function cannot be achieved in general, and that there can locally exist an infinite number of self-consistent policy functions of the class C" with distinct steady states (indeterminacy of self-consistent, differentiable policy functions).
基金the partial result of the National Social Science Fund of China titled"Population Development Simulation and Alternative Fertility Policy"(No.08BRK009)
文摘During the 11th Five-year Plan (2006-2010), the total fertility rate of the mainland of China was 1.481 and was stable with a slight decline, exhibiting a spatial pattern of moderately low fertility in the central and western regions, very low fertility in the east and extremely low fertility in the northeast. Except for a rebound in a few provinces and regions with extremely low fertility rates, the ratio of actual fertility rates to policy fertility rates is still falling. The reduced fertility rate is mainly driven by development, notably the proportion of the total population represented by the exuberantly fertile women of child-bearing age and their greater urbanization, growing level of non-agricultural employment and outflow from rural areas, as well as the assimilative effect of urban production, lifestyles and culturalconcepts upon the agricultural population. Development has catalyzed an irreversible trend of declining fertility; existing fertility policy has proven insufficient to keep fertility rates stable at reasonably low levels. Policy-based rebounds may emerge in urban areas and the east and northeast, where family planning policy has been better implemented; on the other hand, a non-policy-based rebound may have been released. In the central and western rural areas, multiple births occur on average among only 4.12 percent of the younger generation of women. As fertility policy is adjusted and improved, fertility rebounds in transitional fertility policy adjustment can be effectively regulated through a gradual strategy which will not provoke a sharp rebound. The time is ripe for China to conduct a nationally unified adjustment of the existing fertility policy.
文摘The two-child policy was officially proclaimed in the Guideline of the 13th Five-Year Plan and approved in March 2016.This article provides a detailed analysis of the Chinese demographic structure characterised by ageing with sub-replacement fertility.It argues that the universal two-child policy is timely and necessary for the New Normal economy.The policy has significance in relieving socio-economic pressure and promoting economic growth,for which it is not only a necessary premise but also a sufficient condition.Having reviewed the evolution of the demographic transition theory,this research undertakes a comparative analysis of different stages of demographic transition in different regions across the world.It further investigates the three stages of successful demographic transition in China.The universally adopted two-child policy,as it meets the requirements of demographic transition,is also inevitable for socio-economic development.
基金the National Natural Science Foundation of China(Grant Nos.61936010 and 61876096)the National Key R&D Program of China(Grant No.2018YFC0830200)。
文摘Due to the significance and value in human-computer interaction and natural language processing,task-oriented dialog systems are attracting more and more attention in both academic and industrial communities.In this paper,we survey recent advances and challenges in task-oriented dialog systems.We also discuss three critical topics for task-oriented dialog systems:(1)improving data efficiency to facilitate dialog modeling in low-resource settings,(2)modeling multi-turn dynamics for dialog policy learning to achieve better task-completion performance,and(3)integrating domain ontology knowledge into the dialog model.Besides,we review the recent progresses in dialog evaluation and some widely-used corpora.We believe that this survey,though incomplete,can shed a light on future research in task-oriented dialog systems.
文摘This paper examines the motivations of parent-child co-residence behavior in China using data from the China Health and Retirement Longitudinal Study.We test three possible motives:social norms,self-interest and altruism.We find that social norms play an important role in household co-residence behavior,showing that the belief that"sons take care of parents"is strong,and children in different birth orders take different responsibilities.Taking the one-child policy as a natural experiment,we compared co-residence behavior between only-child and multi-child families.This allowed us to test whether children in multi-child families with wealthier parents more often coreside in order to compete for a bequest.We find that parents'wealth is more appealing to children in multi-child families.The results support the life cycle theory that coresidence decisions are motivated by self-interest.We also find some evidence of altruism when parents and children make co-residence decisions.These findings provide some insights for designing future elder-support policies in China.
基金This work was supported by the Science and Technology Project of State Grid Corporation of China(No.5100-201958522A-0-0-00).
文摘This work proposes a reinforcement learning(RL)approach to tackle the control problem of branch overload relief in large power systems.Accordingly,a control agent is trained to change generators'real power output in order to relieve the stressed branches.For large power systems,this control problem becomes one whose decision space(i.e.,the action space)is both highly-dimensioned and continuous.This makes it extremely difficult to have successful training for RL-based agents.To improve the effectiveness,a data-driven and model-based hybrid approach is proposed to optimize the control by combining RL-agent actions and generator shifting factor-driven actions.Accordingly,with the proposed approach the RL-agent successfully trains on large power systems.The proposed design is tested on both the IEEE 118-bus testing system and a 2749-bus real system.The obtained results show that the proposed hybrid approach outperforms the data-driven training approach.