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41.
Positioning fisheries in a changing world   总被引:1,自引:1,他引:0  
Marine capture fisheries face major and complex challenges: habitat degradation, poor economic returns, social hardships from depleted stocks, illegal fishing, and climate change, among others. The key factors that prevent the transition to sustainable fisheries are information failures, transition costs, use and non-use conflicts and capacity constraints. Using the experiences of fisheries successes and failures it is argued only through better governance and institutional change that encompasses the public good of the oceans (biodiversity, ecosystem integrity, sustainability) and societal values (existence, aesthetic and amenity) will fisheries be made sustainable.  相似文献   
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分析了传统集中式存储管理的遥感影像管理体系的不足,提出了针对当前成几何级数倍增影像大数据管理的解决方案,包括数据集模型和云架构模型;并基于VMWare和ArcGIS平台实现了实验模型;通过实验数据分析,证明了新的数据模型和平台架构的科学性和高效性。  相似文献   
44.
基于实时浮动车位置信息,借助电子围栏技术建立了高速公路收费站排队长度监控模型,并重点解决了难以获取私家车等社会车辆位置信息情况下利用排队时间间接实现高速公路收费站排队长度实时监控的问题。以广州市48个收费站为试点,试验结果表明,该模型能提供通畅、拥堵预警、通知放行、实施放行等状态的实时监测,能为高速公路主管部门提供可靠的决策支持。  相似文献   
45.
首先分析了大数据时代地理信息服务存在的问题,介绍了数据即服务的发展现状。然后提出了一种地理空间数据即服务私有云,并设计了其逻辑结构和功能结构。最后,介绍了三种支撑私有云的关键技术。  相似文献   
46.
星历误差和星钟误差是GPS动态精密单点定位的主要误差源,不同的星历和钟差产品会对结果产生影响。利用IGS网站给出的不同星历和钟差数据及广播星历数据进行计算,采用Waypoint软件进行不同的组合计算,对不同星历和钟差组合对机载GPS数据定位结果进行分析。  相似文献   
47.
当前智慧城市建设如火如荼,各部委、各地市纷纷开展智慧城市建设,云计算是智慧城市建设的主要内容之一,私有云环境建设为云计算提供基础环境,如何根据各地市的实际情况,布设私有云环境,是智慧城市建设面临的重大课题。本文通过对比多种私有云环境建设方法,为中小城市开展云环境搭建,提供技术参考。  相似文献   
48.
We examine the current ‘datafication’ process underway in low- and middle-income countries (LMICs), and the power shifts it is creating in the field of international development. The use of new communications and database technologies in LMICs is generating ‘big data’ (for example from the use of mobile phones, mobile-based financial services and the internet) which is collected and processed by corporations. When shared, these data are also becoming a potentially valuable resource for development research and policy. With these new sources of data, new power structures are emerging within the field of development. We identify two trends in particular, illustrating them with examples: first, the empowerment of public–private partnerships around datafication in LMICs and the consequently growing agency of corporations as development actors. Second, the way commercially generated big data is becoming the foundation for country-level ‘data doubles’, i.e. digital representations of social phenomena and/or territories that are created in parallel with, and sometimes in lieu of, national data and statistics. We explore the resulting shift from legibility (Scott, 1998) to visibility, and the implications of seeing development interventions as a byproduct of larger-scale processes of informational capitalism.  相似文献   
49.
Abstract

In this paper we analyse all currently available simulated climate scenarios, proposed by the Spanish Agency of Meteorology (AEMET), for the period 2010–2040 on the geographical area covered by the Júcar River basin, located in eastern Spain. This is done through the validation of these scenarios using historical records, and by assessing the impact on water resources for the next 30 years by means of a hydrological model. By taking the period 1960–1990 as the control period, a careful comparison of its historical records against AEMET scenarios is performed. Although temperature records are modelled properly, precipitation data are widely underestimated in a range from 8% to 29%. This wide variability observed in the control period is also found in the precipitation scenarios for the period 2010–2040. The impact on water resources shows a great degree of dispersion, ranging from –13.45% to 18.1% with a mean value of –2.13%.
Editor Z.W. Kundzewicz; Associate editor F. Hattermann  相似文献   
50.
In this article, I investigate how and why a street art controversy that emerged in post-Katrina New Orleans was transformed from a dispute over property transgressions to a broader struggle over the meanings of art amidst the city’s devastated condition. The controversy began when a street art initiative by the New Orleans artist Rex Dingler invoked a backlash of anti-graffiti activism. In response, local artists began painting on the walls. When the locals were joined by artists from different cities, the discussion intensified about the merits of street art as well as commentary on and reflection of a city facing systemic decline and property abandonment. Street artists, anti-graffiti activists, and property owners negotiated local private property by placing, removing and retaining graffiti, and both locals and those with no New Orleans attachments had influence. The controversy illustrates how private property functions as a public institution in addition to a system of private ownership.  相似文献   
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