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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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Attribute-based access control policy specification language 被引量:6
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作者 叶春晓 钟将 冯永 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期260-263,共4页
This paper first introduces attribute expression to describe attribute-based access control policy.Secondly,an access control policy enforcement language named A-XACML (attribute-XACML)is proposed,which is an extens... This paper first introduces attribute expression to describe attribute-based access control policy.Secondly,an access control policy enforcement language named A-XACML (attribute-XACML)is proposed,which is an extension of XACML.A-XACML is used as a simple,flexible way to express and enforce access control policies,especially attribute-based access control policy,in a variety of environments.The language and schema support include data types,functions,and combining logic which allow simple and complex policies to be defined.Finally,a system architecture and application case of user-role assignment is given to show how attribute expressions and A-XACML work in access control policy description and enforcement.The case shows that attribute expression and A-XACML can describe and enforce the complex access control policy in a simple and flexible way. 展开更多
关键词 role-based access control policy XML XACML
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基于主动网络的Policy-control研究
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作者 王宣政 钱德沛 马素刚 《计算机工程》 CAS CSCD 北大核心 2007年第4期102-104,共3页
结合主动网络的机制和IntServ体系结构,提出了一种主动网络支持的基于代理-管理者的策略控制机制,可以简化中间节点策略控制复杂性,保证在一个管理域中的策略一致性,并且可以实现控制策略代理的动态部署、更新。在此基础上,提出了... 结合主动网络的机制和IntServ体系结构,提出了一种主动网络支持的基于代理-管理者的策略控制机制,可以简化中间节点策略控制复杂性,保证在一个管理域中的策略一致性,并且可以实现控制策略代理的动态部署、更新。在此基础上,提出了基于发送用户的策略控制方法。 展开更多
关键词 主动网络 策略控制 RSVP
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"Hollow Village" Evolution and Policy Control from the Perspective of Rural Urbanization: A Case Study of Jiangsu Province 被引量:2
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作者 Han SONG 《Asian Agricultural Research》 2016年第3期22-26,共5页
From the perspective of the process of urbanization,this paper puts forward the corresponding public policy control by analyzing the characteristics of " hollowing" at different stages of urbanization. Moreo... From the perspective of the process of urbanization,this paper puts forward the corresponding public policy control by analyzing the characteristics of " hollowing" at different stages of urbanization. Moreover,the paper focuses on the stage of China's current urbanization.Based on the survey of migrant workers,this paper evaluates China's current policies,and argues that the rural " hollowing" is an objective that accompanies urbanization. At different stages of the process of urbanization,the rural " hollowing" presents different characteristics. Local governments should make policy and plan based on the different stages of local urbanization and local conditions,because of the extent of regional differences in economic and social development. This paper aims to guide the rural " hollowing" to develop toward the right direction. 展开更多
关键词 URBANIZATION process RURAL HOLLOWING STAGE characteristics policy control
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STUDY ON THE OPTIMIZATION OF TRANSPORT CONTROL POLICY IN COMMUNICATION NETWORK 被引量:1
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作者 Fan Shuyan Han Weizhan Lu Ran 《Journal of Electronics(China)》 2010年第2期261-266,共6页
In communication networks with policy-based Transport Control on-Demand (TCoD) function,the transport control policies play a great impact on the network effectiveness. To evaluate and optimize the transport policies ... In communication networks with policy-based Transport Control on-Demand (TCoD) function,the transport control policies play a great impact on the network effectiveness. To evaluate and optimize the transport policies in communication network,a policy-based TCoD network model is given and a comprehensive evaluation index system of the network effectiveness is put forward from both network application and handling mechanism perspectives. A TCoD network prototype system based on Asynchronous Transfer Mode/Multi-Protocol Label Switching (ATM/MPLS) is introduced and some experiments are performed on it. The prototype system is evaluated and analyzed with the comprehensive evaluation index system. The results show that the index system can be used to judge whether the communication network can meet the application requirements or not,and can provide references for the optimization of the transport policies so as to improve the communication network effectiveness. 展开更多
关键词 Communication network Comprehensive evaluation index system Network Application Effectiveness (NAE) Transport control on-Demand (TCoD) policy optimization
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Policy Iteration for Optimal Control of Discrete-Time Time-Varying Nonlinear Systems 被引量:1
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作者 Guangyu Zhu Xiaolu Li +2 位作者 Ranran Sun Yiyuan Yang Peng Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第3期781-791,共11页
Aimed at infinite horizon optimal control problems of discrete time-varying nonlinear systems,in this paper,a new iterative adaptive dynamic programming algorithm,which is the discrete-time time-varying policy iterati... Aimed at infinite horizon optimal control problems of discrete time-varying nonlinear systems,in this paper,a new iterative adaptive dynamic programming algorithm,which is the discrete-time time-varying policy iteration(DTTV)algorithm,is developed.The iterative control law is designed to update the iterative value function which approximates the index function of optimal performance.The admissibility of the iterative control law is analyzed.The results show that the iterative value function is non-increasingly convergent to the Bellman-equation optimal solution.To implement the algorithm,neural networks are employed and a new implementation structure is established,which avoids solving the generalized Bellman equation in each iteration.Finally,the optimal control laws for torsional pendulum and inverted pendulum systems are obtained by using the DTTV policy iteration algorithm,where the mass and pendulum bar length are permitted to be time-varying parameters.The effectiveness of the developed method is illustrated by numerical results and comparisons. 展开更多
关键词 Adaptive critic designs adaptive dynamic programming approximate dynamic programming optimal control policy iteration TIME-VARYING
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Research on the effects of command-and-control and market-oriented policy tools on China's energy conservation and emissions reduction innovation 被引量:2
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作者 Qin Ye Shaoqing Dai Gang Zeng 《Chinese Journal of Population,Resources and Environment》 2018年第1期1-11,共11页
The impact of environmental regulation on technology innovation is a hot spot in current research where a large number of empirical studies are based on Porter Hypothesis(PH). However, there are still controversies in... The impact of environmental regulation on technology innovation is a hot spot in current research where a large number of empirical studies are based on Porter Hypothesis(PH). However, there are still controversies in academia about the establishment of "weak" and "narrow" versions of PH. Based on the panel data of application for patent of energy conservation and emission reduction(ECER) technology of Chinese city scale during 2008-2014, comprehensive energy price, pollutant emission, etc., mixed regression model and systematic generalized method of moments method were adopted, respectively,to study the impact of market-oriented and command-and-control policy tool on China's ECER technology innovation. The results show that the environmental regulation hindered the technological innovation in the immediate phase; however, it turned out to be positive in the first-lag phase. Hence, the establishment of "weak" PH is time-bounded. The command-and-control policy tool played a more positive role in promoting technological innovation in the first-lag phase than market-oriented policy tool. Therefore, "narrow" PH is not tenable. The reason is that the main participants of China's ECER technology innovation are state-owned companies and public institutions. Regionally speaking, the impact which command-and-control policy tool has on technological innovation at sight was nonsignificant in the eastern, the central, and the western regions of China whilst market-oriented policy tool had a negative effect. And market-oriented policy tool in the central region had strongest negative effect, which would diminish in the eastern region and become weakest in the western region. This was related to regional energy consumption level and the market economic vitality. 展开更多
关键词 Environmental regulation command-and-control policy tools market-oriented policy tools emissions reduction INNOVATION
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A policy and technical measures for controlling soil and water loss in the Loess Plateau of China
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作者 Wu Qinxiao and Li YinchuNorthwestern Institute of Soil and Water Conservation Academia sinica,Shaanxi,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1990年第2期79-86,共8页
Loess Plateau is the most serious region of soil and water loss in China and the world. The sediment carried into the Yellow River amounts to 1.6 billion tons every year. This paper reviews the factors and reasons for... Loess Plateau is the most serious region of soil and water loss in China and the world. The sediment carried into the Yellow River amounts to 1.6 billion tons every year. This paper reviews the factors and reasons for erosion in this area, and puts forward a comprehensive controlling policy on the basis of the principles of ecology and practise of Chinese scientists for 40 years. In conformity with the policy, a number of technical measures for controlling soil and water loss are suggested. 展开更多
关键词 Loess Plateau soil and water loss controlling policy technical measure.
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Visualization Framework for Inter-Domain Access Control Policy Integration
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作者 潘理 柳宁 訾小超 《China Communications》 SCIE CSCD 2013年第3期67-75,共9页
The rapid increase in resource sharing across domains in the cloud comput- ing environment makes the task of managing inter-domain access control policy integration difficult for the security administrators. Al- thoug... The rapid increase in resource sharing across domains in the cloud comput- ing environment makes the task of managing inter-domain access control policy integration difficult for the security administrators. Al- though a number of policy integration and sec- urity analysis mechanisms have been devel- oped, few focus on enabling the average ad- ministrator by providing an intuitive cognitive sense about the integrated policies, which considerably undermines the usability factor. In this paper we propose a visualization flame- work for inter-domain access control policy integration, which integrates Role Based Ac- cess Control (RBAC) policies on the basis of role-mapping and then visualizes the inte- grated result. The role mapping algorithm in the framework considers the hybrid role hier- archy. It can not only satisfy the security con- straints of non-cyclic inheritance and separa- tion of duty but also make visualization easier. The framework uses role-permission trees and semantic substrates to visualize the integrated policies. Through the interactive policy query visualization, the average administrator can gain an intuitive understanding of the policy integration result. 展开更多
关键词 policy visualization policy integration role based access control role mapping
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访问控制日志驱动的ABAC策略自动提取与优化增强
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作者 夏桐 袁凌云 +1 位作者 车兴亮 陈美宏 《计算机应用研究》 CSCD 北大核心 2024年第2期587-595,共9页
为解决基于属性的访问控制(ABAC)策略自动提取的低质量问题,提出一种基于访问控制日志驱动的ABAC策略自动提取与优化增强方法。首先,构建集成学习模型,将用户行为和权限分配映射为策略逻辑树,识别访问授权决策的关联性及潜在规律,初步... 为解决基于属性的访问控制(ABAC)策略自动提取的低质量问题,提出一种基于访问控制日志驱动的ABAC策略自动提取与优化增强方法。首先,构建集成学习模型,将用户行为和权限分配映射为策略逻辑树,识别访问授权决策的关联性及潜在规律,初步生成策略;其次,通过单属性优化和规则二元约简两种方法深度优化策略,简化策略结构并压缩策略规模;最后,提出基于误差度量的规则冲突解决方法,以增强互斥、完备的ABAC策略,并进一步基于多目标优化的策略性能平衡算法实现不同场景需求的最优模型选择。分别在平衡数据集和稀疏数据集上进行测试和验证,实验结果表明,该方法在平衡数据集上的准确性最高可达96.69%,可将策略规模压缩至原来的19.7%。在稀疏数据集上的准确性最高可达87.74%,可将策略规模压缩至原来的23%。此方法兼顾策略的预测精度与结构的简洁性,同时适用于平衡日志和稀疏日志,确保访问控制系统在实际应用中能够实现高效、安全的访问授权管理。 展开更多
关键词 基于属性的访问控制 策略提取 策略增强 集成学习 多目标优化
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Research on ABAC Access Control Based on Big Data Platform
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作者 Kun Yang Xuanxu Jin Xingyu Zeng 《Journal of Cyber Security》 2021年第4期187-199,共13页
In the environment of big data,the traditional access control lacks effective and flexible access mechanism.Based on attribute access control,this paper proposes a HBMC-ABAC big data access control framework.It solves... In the environment of big data,the traditional access control lacks effective and flexible access mechanism.Based on attribute access control,this paper proposes a HBMC-ABAC big data access control framework.It solves the problems of difficult authority change,complex management,over-authorization and lack of authorization in big data environment.At the same time,binary mapping codes are proposed to solve the problem of low efficiency of policy retrieval in traditional ABAC.Through experimental analysis,the results show that our proposed HBMC-ABAC model can meet the current large and complex environment of big data. 展开更多
关键词 Big data access control abac HADOOP
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A mixed method analysis of the Botswana schistosomiasis control policy and plans using the policy triangle framework
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作者 Kebabonye P.Gabaake Don Eliseo Lucero-Prisno III +1 位作者 Olekae T.Thakadu Nthabiseng A.Phaladze 《Global Health Research and Policy》 2023年第1期147-159,共13页
Background The present goal of the World Health Organization(WHO)2021-2030 roadmap for Neglected Tropical Diseases is to eliminate schistosomiasis as a public health problem,and reduce its prevalence of heavy infectio... Background The present goal of the World Health Organization(WHO)2021-2030 roadmap for Neglected Tropical Diseases is to eliminate schistosomiasis as a public health problem,and reduce its prevalence of heavy infections to less than 1%.Given the evolution and impact of schistosomiasis in the Ngamiland district of Botswana,the aim of this study was to analyze the control policies for the district using the Policy Triangle Framework.Methods The study used a mixed method approaches of an analysis of policy documents and interviews with 12 informants who were purposively selected.Although the informants were recruited from all levels of the NTD sector,the analysis of the program was predominantly from the Ngamiland district.Data were analyzed using Braun and Clarke’s approach to content analysis.Results The study highlights the presence of clear,objectives and targets for the Ngamiland control policy.Another theme was the success in morbidity control,which was realized primarily through cycles of MDA in schools.The contextual background for the policy was high morbidity and lack of programming data.The implementation process of the policy was centralized at the Ministry of Health(MOH)and WHO,and there was minimal involvement of the communities and other stakeholders.The policy implementation process was impeded by a lack of domestic resources and lack of comprehensive policy content on snail control and no expansion of the policy content beyond SAC.The actors were predominately MOH headquarters and WHO,with little representation of the district,local level settings,NGOs,and private sectors.Conclusions The lack of resources and content in the control of environmental determinants and exclusion of other at-risk groups in the policy,impeded sustained elimination of the disease.There is a need to guide the treatment of preschool-aged children and develop national guidelines on treating foci of intense transmission.Moreover,the dynamic of the environmental transmissions and reorientation of the schistosomiasis policy to respond to the burden of schistosomiasis morbidity,local context,and health system context are required. 展开更多
关键词 SCHISTOSOMIASIS control policy Ngamiland Botswana and health policy triangle
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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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Adaptable and Dynamic Access Control Decision-Enforcement Approach Based on Multilayer Hybrid Deep Learning Techniques in BYOD Environment
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作者 Aljuaid Turkea Ayedh M Ainuddin Wahid Abdul Wahab Mohd Yamani Idna Idris 《Computers, Materials & Continua》 SCIE EI 2024年第9期4663-4686,共24页
Organizations are adopting the Bring Your Own Device(BYOD)concept to enhance productivity and reduce expenses.However,this trend introduces security challenges,such as unauthorized access.Traditional access control sy... Organizations are adopting the Bring Your Own Device(BYOD)concept to enhance productivity and reduce expenses.However,this trend introduces security challenges,such as unauthorized access.Traditional access control systems,such as Attribute-Based Access Control(ABAC)and Role-Based Access Control(RBAC),are limited in their ability to enforce access decisions due to the variability and dynamism of attributes related to users and resources.This paper proposes a method for enforcing access decisions that is adaptable and dynamic,based on multilayer hybrid deep learning techniques,particularly the Tabular Deep Neural Network Tabular DNN method.This technique transforms all input attributes in an access request into a binary classification(allow or deny)using multiple layers,ensuring accurate and efficient access decision-making.The proposed solution was evaluated using the Kaggle Amazon access control policy dataset and demonstrated its effectiveness by achieving a 94%accuracy rate.Additionally,the proposed solution enhances the implementation of access decisions based on a variety of resource and user attributes while ensuring privacy through indirect communication with the Policy Administration Point(PAP).This solution significantly improves the flexibility of access control systems,making themmore dynamic and adaptable to the evolving needs ofmodern organizations.Furthermore,it offers a scalable approach to manage the complexities associated with the BYOD environment,providing a robust framework for secure and efficient access management. 展开更多
关键词 BYOD security access control access control decision-enforcement deep learning neural network techniques TabularDNN MULTILAYER dynamic adaptable FLEXIBILITY bottlenecks performance policy conflict
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Factors influencing the tobacco control policy process in Egypt and Iran:a scoping review
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作者 C.Banks S.Rawaf S.Hassounah 《Global Health Research and Policy》 2017年第1期171-181,共11页
Introduction:Tobacco control policy is essential for addressing the growing tobacco consumption seen in the Eastern Mediterranean Region,the single greatest preventable contributor to the non-communicable disease epid... Introduction:Tobacco control policy is essential for addressing the growing tobacco consumption seen in the Eastern Mediterranean Region,the single greatest preventable contributor to the non-communicable disease epidemic.Egypt and Iran have had varied success in using policy to combat this issue.The study aims to identify and compare the factors which have influenced different stages of the policy process-evidence generation,development and implementation.Methods:A scoping review was conducted with a systematic search of 7 databases which was conducted along with searches of Google Scholar,and the World Health Organisation and Eastern Mediterranean Regional Office websites to identify influencing factors at each stage of the policy process.Results:Twenty-seven relevant articles were identified from the literature search.Factors identified as influencing tobacco control policy in these countries were lobbying by the tobacco industry,the rise of water-pipe smoking,lack of political commitment and the lack of resources to for policy implementation.Iran was found to be leading Egypt on all three areas of the policy process.Implementation was found to be the most pivotal part of the policy process and the area in which Egypt was weakest compared to Iran.Conclusion:This study addresses a gap in knowledge concerning tobacco control in the Middle East and has identified multiple factors which are potentially slowing the process of enforcing policy to address tobacco consumption.Iran is the regional leader for tobacco control and it is important for Egypt to assess the transferability of its tactics and immediately start implementing measures to control tobacco use. 展开更多
关键词 Public health Health policy Prevention strategies Tobacco control Implementation science
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Project⁃based Pollutant Emission Control of Diesel Construction Equipment
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作者 XIE Yixin FAN Hongqin 《施工技术(中英文)》 CAS 2024年第17期85-93,共9页
This paper examines project⁃based policies and regulations implemented globally to control and mitigate emissions from diesel⁃powered construction equipment.This study systematically reviews and analyzes various manag... This paper examines project⁃based policies and regulations implemented globally to control and mitigate emissions from diesel⁃powered construction equipment.This study systematically reviews and analyzes various managerial,regulatory,and technical measures adopted across countries and regions,mostly of advanced economy.Key strategies of control include setting emission thresholds,idling restrictions,perform remote online monitoring,operational time limits,setting low emission zones,and enforced registration systems.The review highlights the rationale,implementation details,and experiences gained from these localized approaches,reduces localized emission sources,improve urban air quality and environmental management efficiency. 展开更多
关键词 EQUIPMENT diesel emissions control policy analysis
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Research on Multicloud Access Control Policy Integration Framework
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作者 Peng Zhao Lifa Wu +1 位作者 Zheng Hong He Sun 《China Communications》 SCIE CSCD 2019年第9期222-234,共13页
Multicloud access control is important for resource sharing and security interoperability across different clouds,and heterogeneity of access control policy is an important challenge for cloud mashups.XACML is widely ... Multicloud access control is important for resource sharing and security interoperability across different clouds,and heterogeneity of access control policy is an important challenge for cloud mashups.XACML is widely used in distributed environment as a declaratively fine-grained,attribute-based access control policy language,but the policy integration of XACML lacks formal description and theory foundation.Multicloud Access Control Policy Integration Framework(MACPIF)is proposed in the paper,which consists of Attribute-based Policy Evaluation Model(ABPEM),Four-value Logic with Completeness(FLC)and Four-value Logic based Policy Integration Operators(FLPIOs).ABPEM evaluates access control policy and extends XACML decision to four-value.According to policy decision set and policy integration characteristics,we construct FLC and define FLPIOs including Intersection,Union,Difference,Implication and Equivalence.We prove that MACPIF can achieve policy monotonicity,functional completeness,canonical suitability and canonical completeness.Analysis results show that this framework can meet the requirements of policy integration in Multicloud. 展开更多
关键词 Multicloud ACCESS control policyintegration four-value LOGIC
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On the Transmission Mechanism of the Chinese Land Policy in Macroeconomic-control: A Theoretical Study Based on Modified IS-LM Model
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作者 Linlin DIAO Jinming YAN 《Asian Agricultural Research》 2014年第11期75-80,共6页
The purposes of this paper are to bring land factor into the general fame of national product and develop a new modified‘IS-LM equilibrium model',aiming to find out the impacts of land factor on the effective all... The purposes of this paper are to bring land factor into the general fame of national product and develop a new modified‘IS-LM equilibrium model',aiming to find out the impacts of land factor on the effective allocation of capital between total supply and total demand constituting gross national product,to analyze the relation mechanism among land factor and macroeconomic variables,and to discuss the theoretical mechanism under which land,fiscal and monetary policy are integrated. Methods employed include econometrics and model analysis. The results indicate that:( i) on the conditions that the equilibrium of supply and demand in land market,the modified IS-LM model taking into account land factor successfully performs transmission mechanism of land policy participation in macroeconomic-control by means of money capital regulation;( ii) the direction and intensity of land policy control are effected by elasticity of land supply and land price,meanwhile different characteristics of land supply elasticity exit in different stages of economic development;( iii) the realization of IS-LM equilibrium requires the aggregate effects of fiscal,monetary and land policy. It is concluded that land policies for macroeconomic-control drives land price higher,and land supply regulation would diminish financial effect. During the economic expansion or recovery period,the effect of expansionary land policy would be counteracted by high land price. During the economic transition or recession period,the government could control economical operation better through tightening land policy. 展开更多
关键词 LAND economy LAND policy IS-LM model MACROECONOMIC
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一种ABAC静态策略冲突检测算法 被引量:6
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作者 刘江 张红旗 +1 位作者 代向东 王义功 《计算机工程》 CAS CSCD 2013年第6期200-204,共5页
在分布式计算环境下,传统基于属性的静态访问控制策略多存在扩展性差、难以实现等问题。针对上述问题,提出一种基于策略属性分解的冲突检测算法。该算法对策略属性进行分解,构造策略属性分解图,判断策略属性值之间的相交关系,根据静态... 在分布式计算环境下,传统基于属性的静态访问控制策略多存在扩展性差、难以实现等问题。针对上述问题,提出一种基于策略属性分解的冲突检测算法。该算法对策略属性进行分解,构造策略属性分解图,判断策略属性值之间的相交关系,根据静态策略冲突的定义进行策略冲突检测,从而提高策略冲突检测算法的可扩展性和易实现性。实验结果表明,该算法对静态策略冲突的检测率接近85%。 展开更多
关键词 基于属性的访问控制模型 策略管理 静态策略 策略冲突 策略属性分解 冲突检测
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Novel scheme to specify and integrate RBAC policy based on ontology 被引量:1
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作者 孙小林 卢正鼎 +2 位作者 李瑞轩 王治刚 文坤梅 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期394-398,共5页
To describe and integrate various policies applied in different domains, the definition of the family of OntoRBAC based on the ontology of a general role-based access control (RBAC) policy is proposed, which can sup... To describe and integrate various policies applied in different domains, the definition of the family of OntoRBAC based on the ontology of a general role-based access control (RBAC) policy is proposed, which can support and extend the RBAC96 model. The uniform ontology-based description mechanism of secure policies is applied in OntoRBAC, which can be used to describe different secure policies in distributed systems and integrate policies in semantic level with upper concepts. In addition, some rules have been defined to reason within the OntoRBAC to extend the inference algorithms in ontology, which makes the system accommodate itself to RBAC policies better. 展开更多
关键词 ONTOLOGY policy role-based access control
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