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71.
The Myth of Location Privacy in the United States: Surveyed Attitude Versus Current Practices 总被引：1，自引：0，他引：1
In the United States, legal steps have been taken to protect personal privacy, which is viewed as an individual's fundamental right. Location privacy (i.e., protection of personal and location information), however, has not received equal attention in the legal system. Given the recent popularity of location-based services (e.g., cell phones), it is possible to obtain an individual's location information easily and precisely. An investigation of public perception of privacy in the United States indicated that survey responders (1) were unaware of legal implications of location privacy violation and (2) believed that there should be location privacy protection similar to that provided by the Health Insurance Portability and Accountability Act and the Family Educational Rights and Privacy Act. 相似文献
72.
ABSTRACTThis review article discusses the climate, water resources and historical droughts of Africa, drought indices, vulnerability, impact of global warming and land use for drought-prone regions in West, southern and the Greater Horn of Africa, which have suffered recurrent severe droughts in the past. Recent studies detected warming and drying trends in Africa since the mid 20th century. Based on the Fourth Assessment Report of the Intergovernmental Panel on Climate Change and the Coupled Model Intercomparison Project Phase 5 (CMIP5), both northern and southern Africa are projected to experience drying, such as decreasing precipitation, runoff and soil moisture in the 21st century and could become more vulnerable to the impact of droughts. The daily maximum temperature is projected to increase by up to 8°C (RCP8.5 of CMIP5), precipitation indices such as total wet day precipitation (PRCPTOT) and heavy precipitation days (R10 mm) could decrease, while warm spell duration (WSDI) and consecutive dry days (CDD) could increase. Uncertainties of the above long-term projections, teleconnections to climate anomalies such as ENSO and the Madden-Julian Oscillation, which could also affect the water resources of Africa, and capacity building in terms of physical infrastructure and non-structural solutions are also discussed. Given that traditional climate and hydrological data observed in Africa are generally limited, satellite data should also be exploited to fill the data gap for Africa in the future.
Editor D. Koutsoyiannis; Associate editor N. Ilich 相似文献
73.
地理空间框架是数字城市乃至智慧城市建设的重要基础,其应用推广的好坏关系到系统能否长效运行,是重中之重。本文以数字柳州地理空间框架为例,分析应用推广的现状与存在的问题,探索应用推广的模式,总结应用推广的内容与方法,并结合柳州实际情况进行了实践,搭建了教育学区专题应用、存量房价格认证服务平台、人口电子地图管理系统、三维土地供应系统,并与数字化城市管理系统实现了对接,同时在公众网搭建了地理信息公众服务系统。 相似文献
74.
多重空间数据因其可用性及几何和主题方面的质量差异,催生了针对数据挖掘方法研究的新系统开发,其中包括了异构空间数据结构分析与改进的处理进程。本文介绍了空间数据融合系统（ DAFU）的概念、架构与功能性方面的内容,DAFU能够有效使用异构空间数据信息并可进行地理数据的个体使用。 相似文献
75.
刘利 《测绘与空间地理信息》2013,(9)
在全面介绍美国地理信息技术能力素质模型（ GTCM ）、地理信息职业、地理信息课程培训和认证体系的基础上,提出了要研究制定我国地理信息职业能力标准、新增地理信息职业类型、充分参考和利用GTCM模型、建立人才交流平台、加强地理信息劳动力调查研究,以促进我国地理信息劳动力和产业发展。 相似文献
76.
王少燕 《测绘与空间地理信息》2013,36(7):130-132
随着国家电网公司空间信息服务平台的建设和2000国家大地坐标系(CGCS 2000)的启用,迫切需要将各省不同坐标系的空间数据统一转换到CGCS 2000,从而实现电网空间信息服务平台的纵向贯通及空间数据资源的整合和共享。本文根据电力GIS空间数据资源的特点及行业情况,阐述了电网GIS中现有成果从独立坐标系向CGCS 2000转换的实现,并提出了对转换成果的验证方法。 相似文献
77.
3维可视化平台是数字城市地理空间框架的重要组成部分,本文介绍了数字马鞍山建设中3维平台的设计与实现思路。从2,3维协同服务的角度设计了3维建设技术路线,并对海量数据传输加载及2,3维联动等关键问题提出了有益的解决方案。为其他城市建设地理空间框架提供借鉴。 相似文献
78.
《International Journal of Digital Earth》2013,6(5):411-431
With growing demand on multi-purpose or multi-modal navigation, the route calculation needs to traverse semantically enriched road networks for different transportation modes. Currently, operational route planning algorithms reveal rather limited performances or their potential for comprehensive applications are constrained by the unavailable or insufficient interoperation among the underlying geo-data that are separately maintained in different spatial databases. To overcome this limitation, a novel approach has been proposed to integrate the routing-relevant information from different data sources, which involves three processes: (1) automatic matching to identify the corresponding road objects between different datasets; (2) interaction to refine the automatic matching result; and (3) transferring the routing-relevant information from one data-set to another. In process (1), the Delimited Stroke Oriented algorithm is employed to achieve the automatic data matching between different datasets, which has revealed a high matching rate and certainty. However uncertain matching problems occur in areas where topological conditions are too complicated or inconsistent. The remaining unmatched or wrongly matched objects are treated in process (2), with the help of a series of interaction tools. On the basis of refined matching results after the interaction, process (3) is dedicated to automatic integration of the routing-relevant information from different data sources. 相似文献
79.
《International Journal of Digital Earth》2013,6(9):901-922
ABSTRACTSpatial online analytical processing (OLAP) and spatial data warehouse (SDW) systems are geo-business intelligence technologies that enable the analysis of huge volumes of geographic data. In the last decade, the conceptual design and implementation of SDWs that integrate spatial data, which are represented using the vector model, have been extensively investigated. However, the integration of field data (a continuous representation of spatial data) in SDWs is a recent unresolved research issue. Enhancing SDWs with field data improves the spatio-multidimensional analysis capabilities with continuity and multiresolutions. Motivated by the need for a conceptual design tool and relational online analytical processing (ROLAP) implementation, we propose a UML profile for SDWs that integrates a regular grid of points and supports continuity and multiresolutions. We also propose an efficient implementation of a ROLAP architecture. 相似文献
80.
《International Journal of Digital Earth》2013,6(10):1070-1076
ABSTRACTIn this opinion paper, we, a group of scientists from environmental-, geo-, ocean- and information science, argue visual data exploration should become a common analytics approach in Earth system science due to its potential for analysis and interpretation of large and complex spatio-temporal data. We discuss the challenges that appear such as synthesis of heterogeneous data from various sources, reducing the amount of information and facilitating multidisciplinary, collaborative research. We argue that to fully exploit the potential of visual data exploration, several bottlenecks and challenges have to be addressed: providing an efficient data management and an integrated modular workflow, developing and applying suitable visual exploration concepts and methods with the help of effective and tailored tools as well as generating and raising the awareness of visual data exploration and education. We are convinced visual data exploration is worth the effort since it significantly facilitates insight into environmental data and derivation of knowledge from it. 相似文献