乡村是人居环境重要的组成部分,乡村景观是兼具多重价值的复合景观系统。“美丽乡村”与“乡村振兴”政策的推动与实施,对乡村景观的研究与建设提出了更高的要求。以Web of Science(WoS)核心合集数据库和中国知网(CNKI)为数据源,基于Cit...乡村是人居环境重要的组成部分,乡村景观是兼具多重价值的复合景观系统。“美丽乡村”与“乡村振兴”政策的推动与实施,对乡村景观的研究与建设提出了更高的要求。以Web of Science(WoS)核心合集数据库和中国知网(CNKI)为数据源,基于CiteSpace文献计量分析软件对2000—2020年国内外乡村景观研究热点进行分析。结果表明,国外乡村景观研究热点主要包括乡村景观生态系统服务、乡村景观评价、乡村景观管理与保护、乡村景观多样性,国内研究热点主要包括乡村景观规划设计、乡村景观政策、乡村旅游景观、乡村景观评价与保护。分析国内外乡村景观的研究背景及驱动因素,对比两者在研究视角、理论与方法3个方面的差异,为探究乡村景观未来可能的研究方向提供了基础,提出国内的乡村景观研究未来应持续关注乡村景观多种功能和价值,健全评价与保护机制,完善理论与方法框架。展开更多
With the increasing popularity of mobile devices and the wide adoption of mobile Apps,an increasing concern of privacy issues is raised.Privacy policy is identified as a proper medium to indicate the legal terms,such ...With the increasing popularity of mobile devices and the wide adoption of mobile Apps,an increasing concern of privacy issues is raised.Privacy policy is identified as a proper medium to indicate the legal terms,such as the general data protection regulation(GDPR),and to bind legal agreement between service providers and users.However,privacy policies are usually long and vague for end users to read and understand.It is thus important to be able to automatically analyze the document structures of privacy policies to assist user understanding.In this work we create a manually labelled corpus containing 231 privacy policies(of more than 566,000 words and 7,748 annotated paragraphs).We benchmark our data corpus with 3 document classification models and achieve more than 82%on F1-score.展开更多
基于位置的服务(location based service,LBS)得到了广泛应用,同时,用户的位置数据面临着巨大的隐私风险。因此,针对现有位置隐私方法中存在攻击者通过分析用户移动模式降低用户位置匿名度的问题,提出基于转移概率的位置隐私保护算法,...基于位置的服务(location based service,LBS)得到了广泛应用,同时,用户的位置数据面临着巨大的隐私风险。因此,针对现有位置隐私方法中存在攻击者通过分析用户移动模式降低用户位置匿名度的问题,提出基于转移概率的位置隐私保护算法,通过马尔可夫链对用户的移动模式建模得到用户的转移概率,根据转移概率构建最优保护位置集,用策略图形式化保护位置集,通过拉普拉斯机制发布最优位置。通过实验分析,所提算法在保证用户位置隐私和发布效用的同时,拥有较低的时间成本。展开更多
Government policy-group integration and policy-chain inference are significant to the execution of strategies in current Chinese society.Specifically,the coordination of hierarchical policies implemented among governm...Government policy-group integration and policy-chain inference are significant to the execution of strategies in current Chinese society.Specifically,the coordination of hierarchical policies implemented among government departments is one of the key challenges to rural revitalization.In recent years,various well-established quantitative methods have been proposed to evaluate policy coordination,but the majority of these relied on manual analysis,which can lead to subjective results.Thus,in this paper,a novel approach called“policy knowledge graph for the coordination among the government departments”(PG-CODE)is proposed,which incorporates topic modeling into policy knowledge graphs.Similar to a knowledge graph,a policy knowledge graph uses a graph-structured data model to integrate policy discourse.With latent Dirichlet allocation embedding,a policy knowledge graph could capture the underlying topics of the policies.Furthermore,coordination strength and topic diffusion among hierarchical departments could be inferred from the PG-CODE,as it can provide a better representation of coordination within the policy space.We implemented and evaluated the PG-CODE in the field of rural innovation and entrepreneurship policy,and the results effectively demonstrate improved coordination among departments.展开更多
文摘乡村是人居环境重要的组成部分,乡村景观是兼具多重价值的复合景观系统。“美丽乡村”与“乡村振兴”政策的推动与实施,对乡村景观的研究与建设提出了更高的要求。以Web of Science(WoS)核心合集数据库和中国知网(CNKI)为数据源,基于CiteSpace文献计量分析软件对2000—2020年国内外乡村景观研究热点进行分析。结果表明,国外乡村景观研究热点主要包括乡村景观生态系统服务、乡村景观评价、乡村景观管理与保护、乡村景观多样性,国内研究热点主要包括乡村景观规划设计、乡村景观政策、乡村旅游景观、乡村景观评价与保护。分析国内外乡村景观的研究背景及驱动因素,对比两者在研究视角、理论与方法3个方面的差异,为探究乡村景观未来可能的研究方向提供了基础,提出国内的乡村景观研究未来应持续关注乡村景观多种功能和价值,健全评价与保护机制,完善理论与方法框架。
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.61802275 and U1836214)the Innovation fund of Tianjin University(2020XRG-0022).
文摘With the increasing popularity of mobile devices and the wide adoption of mobile Apps,an increasing concern of privacy issues is raised.Privacy policy is identified as a proper medium to indicate the legal terms,such as the general data protection regulation(GDPR),and to bind legal agreement between service providers and users.However,privacy policies are usually long and vague for end users to read and understand.It is thus important to be able to automatically analyze the document structures of privacy policies to assist user understanding.In this work we create a manually labelled corpus containing 231 privacy policies(of more than 566,000 words and 7,748 annotated paragraphs).We benchmark our data corpus with 3 document classification models and achieve more than 82%on F1-score.
文摘基于位置的服务(location based service,LBS)得到了广泛应用,同时,用户的位置数据面临着巨大的隐私风险。因此,针对现有位置隐私方法中存在攻击者通过分析用户移动模式降低用户位置匿名度的问题,提出基于转移概率的位置隐私保护算法,通过马尔可夫链对用户的移动模式建模得到用户的转移概率,根据转移概率构建最优保护位置集,用策略图形式化保护位置集,通过拉普拉斯机制发布最优位置。通过实验分析,所提算法在保证用户位置隐私和发布效用的同时,拥有较低的时间成本。
基金supported by the National Social Science Fund of China(No.20BGL231)the Natural Science Foundation of Hubei Province(No.2018CFB380)。
文摘Government policy-group integration and policy-chain inference are significant to the execution of strategies in current Chinese society.Specifically,the coordination of hierarchical policies implemented among government departments is one of the key challenges to rural revitalization.In recent years,various well-established quantitative methods have been proposed to evaluate policy coordination,but the majority of these relied on manual analysis,which can lead to subjective results.Thus,in this paper,a novel approach called“policy knowledge graph for the coordination among the government departments”(PG-CODE)is proposed,which incorporates topic modeling into policy knowledge graphs.Similar to a knowledge graph,a policy knowledge graph uses a graph-structured data model to integrate policy discourse.With latent Dirichlet allocation embedding,a policy knowledge graph could capture the underlying topics of the policies.Furthermore,coordination strength and topic diffusion among hierarchical departments could be inferred from the PG-CODE,as it can provide a better representation of coordination within the policy space.We implemented and evaluated the PG-CODE in the field of rural innovation and entrepreneurship policy,and the results effectively demonstrate improved coordination among departments.
