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Empirical Bayes Absolute Error Loss Estimation for Parameter of One-Side Truncation Distribution Families
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作者 李金平 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期20-22,共3页
In this paper we propose an absolute error loss EB estimator for parameter of one-side truncation distribution families. Under some conditions we have proved that the convergence rates of its Bayes risk is o, where 0&... In this paper we propose an absolute error loss EB estimator for parameter of one-side truncation distribution families. Under some conditions we have proved that the convergence rates of its Bayes risk is o, where 0<λ,r≤1,Mn≤lnln n (for large n),Mn→∞ as n→∞. 展开更多
关键词 one-side truncation distribution families absolute error loss function empirical Bayes estimator convergence rates
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One-sided empirical Bayes test for location parameter in Gamma distribution 被引量:1
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作者 YUAN Min ZHANG Qian WEI Lai-sheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2018年第3期287-297,共11页
In this paper, we devote to constructing the one-sided empirical Bayes(EB) test for the location parameter in the Gamma distribution by nonparametric method. Under some mild conditions, we prove that the EB test is as... In this paper, we devote to constructing the one-sided empirical Bayes(EB) test for the location parameter in the Gamma distribution by nonparametric method. Under some mild conditions, we prove that the EB test is asymptotically optimal with the rate of the order O(n^(-δs/(2s+1))), where 1/2 ≤ δ < 1 and s > 1 is a given natural number. An example is also given to illustrate that the conditions of the main theorems are easily satisfied. 展开更多
关键词 three parameter Gamma distribution location parameter one-sided empirical Bayes test asymptotically optimality convergence rate
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An Efficient Second-Order Convergent Scheme for One-Side Space Fractional Diffusion Equations with Variable Coefficients 被引量:1
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作者 Xue-lei Lin Pin Lyu +2 位作者 Michael KNg Hai-Wei Sun Seakweng Vong 《Communications on Applied Mathematics and Computation》 2020年第2期215-239,共25页
In this paper,a second-order fnite-diference scheme is investigated for time-dependent space fractional difusion equations with variable coefcients.In the presented scheme,the Crank-Nicolson temporal discretization an... In this paper,a second-order fnite-diference scheme is investigated for time-dependent space fractional difusion equations with variable coefcients.In the presented scheme,the Crank-Nicolson temporal discretization and a second-order weighted-and-shifted Grünwald-Letnikov spatial discretization are employed.Theoretically,the unconditional stability and the second-order convergence in time and space of the proposed scheme are established under some conditions on the variable coefcients.Moreover,a Toeplitz preconditioner is proposed for linear systems arising from the proposed scheme.The condition number of the preconditioned matrix is proven to be bounded by a constant independent of the discretization step-sizes,so that the Krylov subspace solver for the preconditioned linear systems converges linearly.Numerical results are reported to show the convergence rate and the efciency of the proposed scheme. 展开更多
关键词 one-side space fractional difusion equation Variable difusion coefcients Stability and convergence High-order fnite-diference scheme Preconditioner
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The Best m-Term One-Sided Approximation of Besov Classes by the Trigonometric Polynomials
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作者 Rensuo Li Yongping Liu 《Advances in Pure Mathematics》 2012年第3期183-189,共7页
In this paper, we continue studying the so called best m-term one-sided approximation and Greedy-liked one-sided ap- proximation by the trigonometric polynomials. The asymptotic estimations of the best m-terms one-sid... In this paper, we continue studying the so called best m-term one-sided approximation and Greedy-liked one-sided ap- proximation by the trigonometric polynomials. The asymptotic estimations of the best m-terms one-sided approximation by the trigonometric polynomials on some classes of Besov spaces in the metricLp(Td(1≤p≤∞ are given. 展开更多
关键词 BESOV CLASSES m-Term APPROXIMATION one-sideD APPROXIMATION Trigonometric Polynomial Greedy Algorithm
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SRv6 Policy业务可靠性方案探讨
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作者 孟丽珠 宋盈 陈燕 《邮电设计技术》 2024年第4期66-70,共5页
介绍了SRv6 Policy、SBFD技术及5G承载网络SRv6 Policy业务可靠性方案。针对SBFD误触发问题,提出了在被动端生成BSID、部署引流策略及设置不同检测周期等3种完善措施,这些措施不仅提高了业务的可靠性,还显著提升了网络服务能力.
关键词 SRv6 policy SBFD 业务可靠性
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Variation Inequalities for the Commutators of One-Sided Calderón-Zygmund Singular Integrals with Lipschitz Functions
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作者 Tingting Juan Xianming Hou 《Advances in Pure Mathematics》 2021年第12期978-987,共10页
In this paper, we establish the weighted <span style="white-space:nowrap;"><em>L</em><sup><em>p</em></sup></span> <span style="white-space:nowrap;"... In this paper, we establish the weighted <span style="white-space:nowrap;"><em>L</em><sup><em>p</em></sup></span> <span style="white-space:nowrap;">(1 < <em>p</em> < ∞)</span> boundedness of variation operator for the commutators generated by one-sided Calderón-Zygmund singular integrals with Lipschitz functions. 展开更多
关键词 VARIATION one-sided Singular Integrals COMMUTATOR Lipschitz Functions
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A Study on the Multiple Differential Structure of Development in China^s Ethnic Areasand Exploiting the Differentiation and Collaborative Policy—On the New Form of China’s Ethnic Relations and the New System of Ethnic Policies
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作者 Xu Hongwei 《民族学刊》 2016年第3期119-120,共2页
A fter 60 years of im plem entation, the ethnic regional autonomous policy has provided basic p o litica l support for promoting the common development and prosperity of a ll ethnic groups.
关键词 the STRUCTURE of MULTIPLE DISPARITY hierarchical difference complex cooperation the DEVELOPMENT of policy.
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A View of Beijing’s Traffic Policy:Evaluation on the Policies Released in 2010 to Ease Traffic Congestion
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作者 Xu Wang 《Macro Management & Public Policies》 2021年第1期45-52,共8页
In today’s society where the economy is developing rapidly and the process of urbanization is accelerating,the traffic in major cities in China is facing tremendous pressure.The economy of Beijing has developed rapid... In today’s society where the economy is developing rapidly and the process of urbanization is accelerating,the traffic in major cities in China is facing tremendous pressure.The economy of Beijing has developed rapidly,its population is dense,the living standard of people has improved significantly,and the number of cars has increased dramatically.From the end of 2005 to the end of November 2010,motor vehicles in Beijing increased from about 2.58 million to about 4.69 million.The problem of traffic congestion has become more prominent,affecting the daily lives of the residents. 展开更多
关键词 Traffic policy Beijing traffic CONGESTION policy intervention
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Comments by opponents on the British Medical Association’s guidance on non-therapeutic male circumcision of children seem one-sided and may undermine public health
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作者 Stephen Moreton Guy Cox +3 位作者 Mark Sheldon Stefan A Bailis Jeffrey D Klausner Brian J Morris 《World Journal of Clinical Pediatrics》 2023年第5期244-262,共19页
The British Medical Association(BMA)guidance on non-therapeutic circumcision(NTMC)of male children is limited to ethical,legal and religious issues.Here we evaluate criticisms of the BMA’s guidance by Lempert et al.W... The British Medical Association(BMA)guidance on non-therapeutic circumcision(NTMC)of male children is limited to ethical,legal and religious issues.Here we evaluate criticisms of the BMA’s guidance by Lempert et al.While their arguments promoting autonomy and consent might be superficially appealing,their claim of high procedural risks and negligible benefits seem one-sided and contrast with high quality evidence of low risk and lifelong benefits.Extensive literature reviews by the American Academy of Pediatrics and the United States Centers for Disease Control and Prevention in developing evidence-based policies,as well as risk-benefit analyses,have found that the medical benefits of infant NTMC greatly exceed the risks,and there is no reduction in sexual function and pleasure.The BMA’s failure to consider the medical benefits of early childhood NTMC may partly explain why this prophylactic intervention is discouraged in the United Kingdom.The consequence is higher prevalence of preventable infections,adverse medical conditions,suffering and net costs to the UK’s National Health Service for treatment of these.Many of the issues and contradictions in the BMA guidance identified by Lempert et al stem from the BMA’s guidance not being sufficiently evidence-based.Indeed,that document called for a review by others of the medical issues surrounding NTMC.While societal factors apply,ultimately,NTMC can only be justified rationally on scientific,evidence-based grounds.Parents are entitled to an accurate presentation of the medical evidence so that they can make an informed decision.Their decision either for or against NTMC should then be respected. 展开更多
关键词 Circumcision Male Child INFECTIONS Risk policy Public health
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Policy Framework for Community and State Policing in Combating Rising Security Challenges in Nigeria
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作者 Ngozi Nwogwugwu Adebusola Morenikeji Odedina 《International Relations and Diplomacy》 2018年第6期334-345,共12页
Viability of decentralizing policing in Nigeria had been on the front burner of security discourse since Nigeria returned to democratic governance in 1999.Valid points had been put forward by both those in support and... Viability of decentralizing policing in Nigeria had been on the front burner of security discourse since Nigeria returned to democratic governance in 1999.Valid points had been put forward by both those in support and those in opposition.The Community Policing Department of the Nigeria Police had remained more of an administrative unit with little impact beyond the Police Community Relations Committee activities.Rising cases of herdsmen attacks of various communities,terrorist insurgency in the North-East,kidnappings across the different geo-political zones had resulted in the need to interrogate the efficacy of effective community policing and state policing as viable options to combating rising security challenges.The study adopted qualitative method,and being a library research relied entirely on secondary data.Sources of data included journals,relevant textbooks,newspapers,magazines,and materials downloaded from internet.The paper argues that the traditional security agencies had failed to effectively combat the many security challenges that Nigeria faces.The combination of the official security agencies and the military had failed to effectively combat insecurity in the country.The local vigilante groups on the other hand had made valuable inroad in curtailing some of the security challenges including terrorist insurgency as a result of their knowledge of the terrain.The paper concludes that to effectively combat the many security challenges,there is a need for new policy framework at the federal and state levels that would decentralize policing and give legal backing for collaboration between the official security agencies under the federal government and state security outfits including the vigilante. 展开更多
关键词 COMMUNITY POLICING STATE POLICING SECURITY CHALLENGES policy framework vigilante
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New Approach to Observer-Based Finite-Time H_(∞)Control of Discrete-Time One-Sided Lipschitz Systems with Uncertainties
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作者 Xinyue Tang Yali Dong Meng Liu 《Journal of Electronic & Information Systems》 2022年第2期1-9,共9页
This paper investigates the finite-time H_(∞)control problem for a class of nonlinear discrete-time one-sided Lipschitz systems with uncertainties.Using the one-sided Lipschitz and quadratically inner-bounded conditi... This paper investigates the finite-time H_(∞)control problem for a class of nonlinear discrete-time one-sided Lipschitz systems with uncertainties.Using the one-sided Lipschitz and quadratically inner-bounded conditions,the authors derive less conservative criterion for the controller design and observer design.A new criterion is proposed to ensure the closed-loop system is finite-time bounded(FTB).The sufficient conditions are established to ensure the closed-loop system is H_(∞)finite-time bounded(H_(∞)FTB)in terms of matrix inequalities.The controller gains and observer gains are given.A numerical example is provided to demonstrate the effectiveness of the proposed results. 展开更多
关键词 Finite-time H_(∞)boundedness Discrete-time systems one-sided Lipschitz system Observer-based control
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Policy Gradient Adaptive Dynamic Programming for Model-Free Multi-Objective Optimal Control
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作者 Hao Zhang Yan Li +2 位作者 Zhuping Wang Yi Ding Huaicheng Yan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期1060-1062,共3页
Dear Editor,In this letter,the multi-objective optimal control problem of nonlinear discrete-time systems is investigated.A data-driven policy gradient algorithm is proposed in which the action-state value function is... Dear Editor,In this letter,the multi-objective optimal control problem of nonlinear discrete-time systems is investigated.A data-driven policy gradient algorithm is proposed in which the action-state value function is used to evaluate the policy.In the policy improvement process,the policy gradient based method is employed. 展开更多
关键词 policy GRADIENT OPTIMAL
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Health financing policies in Sub-Saharan Africa:government ownership or donors’influence?A scoping review of policymaking processes
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作者 Lara Gautier Valéry Ridde 《Global Health Research and Policy》 2017年第1期116-132,共17页
Background:The rise on the international scene of advocacy for universal health coverage(UHC)was accompanied by the promotion of a variety of health financing policies.Major donors presented health insurance,user fee ... Background:The rise on the international scene of advocacy for universal health coverage(UHC)was accompanied by the promotion of a variety of health financing policies.Major donors presented health insurance,user fee exemption,and results-based financing policies as relevant instruments for achieving UHC in Sub-Saharan Africa.The“donor-driven”push for policies aiming at UHC raises concerns about governments’effective buy-in of such policies.Because the latter has implications on the success of such policies,we searched for evidence of government ownership of the policymaking process.Methods:We conducted a scoping review of the English and French literature from January 2001 to December 2015 on government ownership of decision-making on policies aiming at UHC in Sub-Saharan Africa.Thirty-five(35)results were retrieved.We extracted,synthesized and analyzed data in order to provide insights on ownership at five stages of the policymaking process:emergence,formulation,funding,implementation,and evaluation.Results:The majority of articles(24/35)showed mixed results(i.e.ownership was identified at one or more levels of policymaking process but not all)in terms of government ownership.Authors of only five papers provided evidence of ownership at all reviewed policymaking stages.When results demonstrated some lack of government ownership at any of the five stages,we noticed that donors did not necessarily play a role:other actors’involvement was contributing to undermining government-owned decision-making,such as the private sector.We also found evidence that both government ownership and donors’influence can successfully coexist.Discussion:Future research should look beyond indicators of government ownership,by analyzing historical factors behind the imbalance of power between the different actors during policy negotiations.There is a need to investigate how some national actors become policy champions and thereby influence policy formulation.In order to effectively achieve government ownership of financing policies aiming at UHC,we recommend strengthening the State’s coordination and domestic funding mobilization roles,together with securing a higher involvement of governmental(both political and technical)actors by donors. 展开更多
关键词 OWNED policy FORMULATION
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Research on Policy Diffusion Path and Reproduction of River Chief System
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作者 Fang Chen 《Journal of Environmental Protection》 2024年第3期227-245,共19页
The River Chief System (RCS) has evolved from local innovative practices to a national water governance strategy to address the current challenges in China’s water environmental management. In contrast to existing re... The River Chief System (RCS) has evolved from local innovative practices to a national water governance strategy to address the current challenges in China’s water environmental management. In contrast to existing research that focuses on the strengths, weaknesses, and improvements of RCS, this study uses literature study to reveal the dynamic evolution of RCS through three phases, with RCS spreading from developed coastal areas to central and western inland regions. RCS’s diffusion path involves vertical diffusion between central and local levels and horizontal diffusion among local governments. Moreover, RCS has also achieved conceptual spillover, gradually expanding into other governance domains, such as the Lake Chief System, the Field Chief System, the Forestry Chief System, and the integration of multiple chief roles. However, it is essential to scrutinize the phenomenon of applying similar governance mechanisms to different areas, as it may result in challenges such as overburdening local governments, insufficient public participation, oversimplification of differences in natural resource endowments, and limited applicability. This study also provides suggestions on how to address these challenges. The study contributes theoretical insights and policy implications, providing a foundation for practical policy innovation. 展开更多
关键词 Chinese Water Governance policy policy Diffusion River Chief System
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Inactivated H9N2 vaccines developed with early strains do not protect against recent H9N2 viruses:Call for a change in H9N2 control policy
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作者 Yanjing Liu Qingqing Yu +8 位作者 Xiangyu Zhou Wenxin Li Xinwen He Yan Wang Guohua Deng Jianzhong Shi Guobin Tian Xianying Zeng Hualan Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期2144-2148,共5页
H9N2 virus has been widely distributed in wild birds and poultry around the world since its first emergence in the United States of America in 1966(Gu et al.2017;Carnaccini and Perez 2020).The virus appeared in chicke... H9N2 virus has been widely distributed in wild birds and poultry around the world since its first emergence in the United States of America in 1966(Gu et al.2017;Carnaccini and Perez 2020).The virus appeared in chickens in China in the early 1990s,and over the last two decades has gradually become the dominant epidemic subtype(Sun and Liu 2015;Bi et al.2020).Although H9N2 virus infection alone cannot cause severe disease or death in poultry,H9N2 virus-infected birds experience a degree of egg production drop and can be easily infected by other pathogens,thus causing economic losses for poultry industry. 展开更多
关键词 H9N2 POULTRY policy
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Automatic Generation of Attribute-Based Access Control Policies from Natural Language Documents
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作者 Fangfang Shan Zhenyu Wang +1 位作者 Mengyao Liu Menghan Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第9期3881-3902,共22页
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
关键词 Access control policy generation natural language deep learning
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Big Data Analysis of Policy Coordination Paths Based on Latent Dirichlet Allocation Model and Fuzzy-Set Qualitative Comparative Analysis Method
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作者 He Nianchu Jia Junwei +1 位作者 Xu Jiangbo Wen Subin 《China Communications》 SCIE CSCD 2024年第12期309-325,共17页
The selection and coordinated application of government innovation policies are crucial for guiding the direction of enterprise innovation and unleashing their innovation potential.However,due to the lengthy,voluminou... The selection and coordinated application of government innovation policies are crucial for guiding the direction of enterprise innovation and unleashing their innovation potential.However,due to the lengthy,voluminous,complex,and unstructured nature of regional innovation policy texts,traditional policy classification methods often overlook the reality that these texts cover multiple policy topics,leading to lack of objectivity.In contrast,topic mining technology can handle large-scale textual data,overcoming challenges such as the abundance of policy content and difficulty in classification.Although topic models can partition numerous policy texts into topics,they cannot analyze the interplay among policy topics and the impact of policy topic coordination on enterprise innovation in detail.Therefore,we propose a big data analysis scheme for policy coordination paths based on the latent Dirichlet allocation(LDA)model and the fuzzyset qualitative comparative analysis(fsQCA)method by combining topic models with qualitative comparative analysis.The LDA model was employed to derive the topic distribution of each document and the word distribution of each topic and enable automatic classi-fication through algorithms,providing reliable and objective textual classification results.Subsequently,the fsQCA method was used to analyze the coordination paths and dynamic characteristics.Finally,experimental analysis was conducted using innovation policy text data from 31 provincial-level administrative regions in China from 2012 to 2021 as research samples.The results suggest that the proposed method effectively partitions innovation policy topics and analyzes the policy configuration,driving enterprise innovation in different regions. 展开更多
关键词 fsQCA method innovation policy coordination LDA model
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A quantitative study of disruptive technology policy texts:An example of China’s artificial intelligence policy
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作者 Ying Zhou Linzhi Yan Xiao Liu 《Journal of Data and Information Science》 CSCD 2024年第3期155-180,共26页
Purpose:The transformative impact of disruptive technologies on the restructuring of the times has attracted widespread global attention.This study aims to analyze the characteristics and shortcomings of China’s arti... Purpose:The transformative impact of disruptive technologies on the restructuring of the times has attracted widespread global attention.This study aims to analyze the characteristics and shortcomings of China’s artificial intelligence(AI)disruptive technology policy,and to put forward suggestions for optimizing China’s AI disruptive technology policy.Design/methodology/approach:Develop a three-dimensional analytical framework for“policy tools-policy actors-policy themes”and apply policy tools,social network analysis,and LDA topic model to conduct a comprehensive analysis of the utilization of policy tools,cooperative relationships among policy actors,and the trends in policy theme settings within China’s innovative AI technology policy.Findings:We find that the collaborative relationship among the policy actors of AI disruptive technology in China is insufficiently close.Marginal subjects exhibit low participation in the cooperation network and overly rely on central subjects,forming a“center-periphery”network structure.Policy tool usage is predominantly focused on supply and environmental types,with a severe inadequacy in demand-side policy tool utilization.Policy themes are diverse,encompassing topics such as“Intelligent Services”“Talent Cultivation”“Information Security”and“Technological Innovation”,which will remain focal points.Under the themes of“Intelligent Services”and“Intelligent Governance”,policy tool usage is relatively balanced,with close collaboration among policy entities.However,the theme of“AI Theoretical System”lacks a comprehensive understanding of tool usage and necessitates enhanced cooperation with other policy entities.Research limitations:The data sources and experimental scope are subject to certain limitations,potentially introducing biases and imperfections into the research results,necessitating further validation and refinement.Practical implications:The study introduces a three-dimensional analysis framework for disruptive technology policy texts,which is significant for formulating and enhancing disruptive technology policies.Originality/value:This study utilizes text mining and content analysis techniques to quantitatively analyze disruptive technology policy texts.It systematically evaluates China’s AI policies quantitatively,focusing on policy tools,policy actors,policy themes.The study uncovers the characteristics and deficiencies of current AI policies,offering recommendations for formulating and enhancing disruptive technology policies. 展开更多
关键词 Disruptive technologies Artificial intelligence SYNERGIES policy tools Thematic evolution
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Mapping Climate Services for Disaster Risk Management: A Systematic Review and Research Gaps from a Policy Process Perspective
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作者 Aboubacar Issaka Ousman Gaoh Wolfram Laube +1 位作者 Georges Abbevi Abbey Moussa Waongo 《American Journal of Climate Change》 2024年第2期314-360,共47页
Climate services (CS) are crucial for mitigating and managing the impacts and risks associated with climate-induced disasters. While evidence over the past decade underscores their effectiveness across various domains... Climate services (CS) are crucial for mitigating and managing the impacts and risks associated with climate-induced disasters. While evidence over the past decade underscores their effectiveness across various domains, particularly agriculture, to maximize their potential, it is crucial to identify emerging priority areas and existing research gaps for future research agendas. As a contribution to this effort, this paper employs the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology to review the state-of-the-art in the field of climate services for disaster risk management. A comprehensive search across five literature databases combined with a snowball search method using ResearchRabbit was conducted and yielded 242 peer-reviewed articles, book sections, and reports over 2013-2023 after the screening process. The analysis revealed flood, drought, and food insecurity as major climate-related disasters addressed in the reviewed literature. Major climate services addressed included early warning systems, (sub)seasonal forecasts and impact-based warnings. Grounded in the policy processes’ theoretical perspective, the main focus identified and discussed three prevailing policy-oriented priority areas: 1) development of climate services, 2) use-adoption-uptake, and 3) evaluation of climate services. In response to the limitations of the prevalent supply-driven and top-down approach to climate services promotion, co-production emerges as a cross-cutting critical aspect of the identified priority areas. Despite the extensive research in the field, more attention is needed, particularly pronounced in the science-policy interface perspective, which in practice bridges scientific knowledge and policy decisions for effective policy processes. This perspective offers a valuable analytical lens as an entry point for further investigation. Hence, future research agendas would generate insightful evidence by scrutinizing this critical aspect given its importance to institutions and climate services capacity, to better understand intricate facets of the development and the integration of climate services into disaster risk management. 展开更多
关键词 Climate Services Disaster Risk Management policy Process Science-policy Interface Institutional Analysis
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Geographical Distribution of Atmospheric Nitrogen Deposition in China and Its Response to Emission Control Policy
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作者 WEN Zhang YU Ziyin +7 位作者 SI Ruotong XU Wen WANG Kai LIU Lei TANG Aohan ZHANG Fusuo KEITH Goulding LIU Xuejun 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1017-1031,共15页
Atmospheric nitrogen(N)deposition has experienced significant change because of anthropogenic emissions,thereby exerting a pronounced impact on global ecosystem services.With the rapid development of industry and agri... Atmospheric nitrogen(N)deposition has experienced significant change because of anthropogenic emissions,thereby exerting a pronounced impact on global ecosystem services.With the rapid development of industry and agriculture and the swift expansion of urban areas in China since the 1980s,reactive nitrogen(Nr)emissions and N deposition have substantially increased.In pursuit of im-proving air quality,China has implemented a series of environmental protection policies and undertaken diverse measures to reduce pol-lutant emissions.This paper is a review of multivariate data sources of atmospheric N deposition based on the results of literature from 1980 to 2023,and the original data from 1980 to 2020 are summarized,counted and calculated.The main findings are as follows:1)the annual average atmospheric N deposition ranged from approximately 20-40 kg/(ha·yr),with the variability primarily linked to different assessment methods;2)regional disparities were evident in the spatial distribution of N deposition,with elevated values concentrated in areas with intense Nr emissions;3)atmospheric N deposition significantly declined after 2010,particularly the deposition of oxidized N,while reduced N deposition remained stable.These results reflect the effects of China's serious control policies on nitrogen oxide(NO.)emissions and strengthen the importance of agricultural NH3 emission mitigation.This study contributes to a comprehensive understanding of the N dynamics in the emission-deposition process,and provides a scientific foundation for the research of environmental protection,climate change,and sustainable development. 展开更多
关键词 nitrogen deposition emission-deposition relationship reactive nitrogen hotspots emission control policy China
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