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991.
袁睿佳 《资源科学》2019,41(2):405-413
为保障松华坝水库流域的饮水安全,促进滇池流域水污染的防治工作,本文以非点源污染为研究对象,通过专家打分法分析不同景观在该流域非点源污染形成中的贡献,并确定各“源”、“汇”景观的比重,以景观空间负荷对比指数为基础,分别从流域整体与各景观空间要素2个方面,定量研究了流域景观格局与非点源污染的关系。结果显示:①松华坝水库流域整体和各空间要素层面的4个景观空间负荷指数值均小于0.50,表明流域在整体和各景观空间要素层面,均属于“污染截留型”景观格局,即理论上由当前景观格局新产生并排出的非点源污染物极少;②坡度景观空间负荷指数>相对高程景观空间负荷指数>距离景观空间负荷指数,表明加强保护该流域中高海拔陡坡地带的“汇”景观,不仅可以防止形成新的“污染贡献型”景观格局,还可强化其隔离圈式“污染截留型”景观格局,有效阻挡流域中面积最大的“源”景观,位于中高海拔山区的旱地所产生的土壤和养分外流。  相似文献   
992.
本文通过采用校企共建实践教学基地、设置创新型项目化课程教学、研发产品的创新制作以及自主创业设立公司等方法和方式,对平台"产""学""研""用"四大模块进行应用研究,完善和提高平台的专业建设水平,发挥平台技术和研发力量的优势,使之成为既能满足行业企业的需求,又能真正成为培养"创新型人才"的"新平台",为探索高等院校人才培养模式的改革提供新思路。  相似文献   
993.
《争取持久和平,争取人民民主!》是20世纪40年代中后期,欧洲九个社会主义国家的共产党和工人党为了一致行动而建立的情报局机关刊物。该刊物对新中国初期我国经济社会建设及成就进行了大量宣传与报道,对加强我国与世界其他爱好和平、渴求民主的各国人民加强互信、长存友谊贡献很大,也对当前学者研究新中国初期我国经济社会发展的过程、成就和经验等提供了原始史料,学术研究意义也很重大。但是,目前对这份刊物及其发挥过的重大作用了解的人少之又少,时值中国共产党成立100周年之际,对其创刊与发行的历史过程进行回顾、宣传中国社会经济发展的全貌进行展示、推动世界社会主义运动的作用进行肯定,意义都很重大。  相似文献   
994.
Abstract

The Program for Cooperative Cataloging (PCC) has formal relationships with the Library of Congress (LC), Share-VDE, and Linked Data for Production Phase 2 (LD4P2) for work on Bibliographic Framework (BIBFRAME), and PCC institutions have been very active in the exploration of MARC to BIBFRAME conversion processes. This article will review the involvement of PCC in the development of BIBFRAME and examine the work of LC, Share-VDE, and LD4P2 on MARC to BIBFRAME conversion. It will conclude with a discussion of areas for further exploration by the PCC leading up to the creation of PCC conversion specifications and PCC BIBFRAME data.  相似文献   
995.
This paper aims to demonstrate how the huge amount of Social Big Data available from tourists can nurture the value creation process for a Smart Tourism Destination. Applying a multiple-case study analysis, the paper explores a set of regional tourist experiences related to a Southern European region and destination, to derive patterns and opportunities of value creation generated by Big Data in tourism. Findings present and discuss evidence in terms of improving decision-making, creating marketing strategies with more personalized offerings, transparency and trust in dialogue with customers and stakeholders, and emergence of new business models. Finally, implications are presented for researchers and practitioners interested in the managerial exploitation of Big Data in the context of information-intensive industries and mainly in Tourism.  相似文献   
996.
BackgroundThe current state of knowledge regarding the role of non-offending fathers in supporting their sexually abused children is very scarce.ObjectiveThe objective of this study is to further our understanding of fathers’ roles following disclosure of their children’s sexual abuse (SA) by evaluating fathers’ perceptions of the impact of disclosure on their involvement and support of their children.Participants and methodThis qualitative study relies on individual semi-structured interviews conducted with 17 fathers of allegedly abused children.ResultsInductive thematic analysis first highlighted that some reported a period of disengagement from the child during which they put into question their role and attitudes, followed by a period of re-involvement. This period of difficulties experienced by some fathers in regard to their involvement towards their children was due to either their own important psychological distress, their ambivalence towards their child or even because of feelings of uneasiness experienced during physical contact with them. Despite this, findings indicate the presence of thoughts and attitudes that suggest children are a source of concern for fathers. The four forms of abuse-specific support previously observed among mothers (believing the child, seeking out professional services, protecting him/her from the offender, supporting him/her emotionally) were also observed among fathers. In accordance with the activation theory, a form of support specific to fathers, namely, encouraging the child to open up to and explore the world outside the family, thereby, fostering the child’s self-esteem development, was observed and constitutes a relevant finding.ConclusionClinical and empirical implications are discussed.  相似文献   
997.
The implementation of digital contact tracing applications around the world to help reduce the spread of the COVID-19 pandemic represents one of the most ambitious uses of massive-scale citizen data ever attempted. There is major divergence among nations, however, between a “privacy-first” approach which protects citizens’ data at the cost of extremely limited access for public health authorities and researchers, and a “data-first” approach which stores large amounts of data which, while of immeasurable value to epidemiologists and other researchers, may significantly intrude upon citizens’ privacy. The lack of a consensus on privacy protection in the contact tracing process creates risks of non-compliance or deliberate obfuscation from citizens who fear revealing private aspects of their lives – a factor greatly exacerbated by recent major scandals over online privacy and the illicit use of citizens’ digital information, which have heightened public consciousness of these issues and created significant new challenges for any collection of large-scale public data. While digital contact tracing for COVID-19 remains in its infancy, the lack of consensus around best practices for its implementation and for reassuring citizens of the protection of their privacy may already have impeded its capacity to contribute to the pandemic response.  相似文献   
998.
999.
孙宁 《档案管理》2020,(3):12-13
在大数据视域下,以档案管理理论和信息系统安全理论为基础,参考国家相关法规及标准,结合档案管理工作实务,研究当下档案管理工作中的风险,在此基础上初步构建起档案安全管理体系,并对可引入该体系的实用技术进行分析。  相似文献   
1000.
Five hundred million tweets are posted daily, making Twitter a major social media platform from which topical information on events can be extracted. These events are represented by three main dimensions: time, location and entity-related information. The focus of this paper is location, which is an essential dimension for geo-spatial applications, either when helping rescue operations during a disaster or when used for contextual recommendations. While the first type of application needs high recall, the second is more precision-oriented. This paper studies the recall/precision trade-off, combining different methods to extract locations. In the context of short posts, applying tools that have been developed for natural language is not sufficient given the nature of tweets which are generally too short to be linguistically correct. Also bearing in mind the high number of posts that need to be handled, we hypothesize that predicting whether a post contains a location or not could make the location extractors more focused and thus more effective. We introduce a model to predict whether a tweet contains a location or not and show that location prediction is a useful pre-processing step for location extraction. We define a number of new tweet features and we conduct an intensive evaluation. Our findings are that (1) combining existing location extraction tools is effective for precision-oriented or recall-oriented results, (2) enriching tweet representation is effective for predicting whether a tweet contains a location or not, (3) words appearing in a geography gazetteer and the occurrence of a preposition just before a proper noun are the two most important features for predicting the occurrence of a location in tweets, and (4) the accuracy of location extraction improves when it is possible to predict that there is a location in a tweet.  相似文献   
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