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111.
Use of public participation geographic information systems (PPGIS) studies that collect local knowledge in a spatial format is increasing as a tool in natural resources management. Qualitative PPGIS studies have been conducted as individual interviews, as workshops, and in focus groups. As the number of qualitative PPGIS studies increases, so does the need to understand their quality. Saturation, the point when the researcher determines that the collection of additional data will provide minimal new information as it relates to a particular issue, directly reflects on the validity of the study. While the concept of saturation is well established, it is still inconsistently assessed and reported. Furthermore, how saturation applies to qualitatively collected spatial data has not been addressed. A method is presented to assess spatial saturation of qualitative PPGIS data from 19 focus groups that were conducted to investigate important places for recreation, livelihoods, and the environment in the Florida Panhandle. 相似文献
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基于PCA和LOGIT模型的网络入侵检测方法 总被引:1,自引:0,他引:1
李蕊 《成都信息工程学院学报》2014,29(3):261-267
针对高维度网络数据进行多类攻击行为检测的需求,提出一种基于PCA和Logit模型的网络入侵检测方法,通过PCA对网络数据降维、简化数据集和多项式Logit模型实现对不同攻击行为的识别并判别其类型。实验结果表明,方法在网络入侵识别上具有较理想的效果。 相似文献
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Urban growth is increasing the demand for freshwater resources, yet surprisingly the water sources of the world's large cities have never been globally assessed, hampering efforts to assess the distribution and causes of urban water stress. We conducted the first global survey of the large cities’ water sources, and show that previous global hydrologic models that ignored urban water infrastructure significantly overestimated urban water stress. Large cities obtain 78 ± 3% of their water from surface sources, some of which are far away: cumulatively, large cities moved 504 billion liters a day (184 km3 yr−1) a distance of 27,000 ± 3800 km, and the upstream contributing area of urban water sources is 41% of the global land surface. Despite this infrastructure, one in four cities, containing $4.8 ± 0.7 trillion in economic activity, remain water stressed due to geographical and financial limitations. The strategic management of these cities’ water sources is therefore important for the future of the global economy. 相似文献
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Scholars have proposed that the Protection Motivation Theory provides a valuable framework to explain pro-environmental choices, by employing a wide set of predictors, such as the costs and benefits of current (maladaptive) behavior as well as prospective adaptive behavior. However, no comprehensive empirical tests of the Protection Motivation Theory in the slow onset environmental risk domain have been published yet to our knowledge. This paper aims at closing this gap. We first conceptualized the Protection Motivation Theory for the use in this environmental domain. Next, we present results of a questionnaire study among a large representative sample of Dutch drivers that showed that the Protection Motivation Theory is a relevant theory for modeling different indicators of full electric vehicle adoption. Notably, all theoretical antecedents proved to be significant predictors of different adoption indicators. Respondents were particularly more likely to adopt an electric vehicle when they perceived the negative consequences caused by conventional vehicles as more severe, and when they expected electric vehicles to decrease these consequences. The most important barriers for electric vehicle adoption were perceived high monetary and non-monetary costs of electric vehicles, and benefits associated with the use of a conventional vehicle. Interestingly, we found that environmental risks are more prominent in predicting close adoption indicators; while energy security risks are more prominent in predicting distant adoption indicators. As expected, our findings suggest that both collective concerns and individual concerns predict different indicators of adoption. Individual concerns (in particular perceived costs of driving an electric vehicle) played a more prominent role when predicting close measures of adoption, while collective concerns (e.g., perceived severity of environmental and energy security risks) played a somewhat more prominent role when predicting distant measures of adoption. Implications for research and practice are provided. 相似文献
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地理信息数据是国家国防建设和国民经济发展的重要基础数据,随着数字化、信息化及云计算等技术的发展,地理信息数据的安全威胁日益严峻,本文面对移动平台上地理信息数据安全存储、高效传输和实时信息解密及处理等挑战,提出了一种基于TEA算法的地理信息数据安全保护技术,该技术采用循环迭代的移位和异或运算实现对地理信息数据的加密和解密,可以实现移动平台端地理信息数据的高安全加密存储和高性能实时解密处理,并采用该算法对SRTM数据进行处理和分析。试验结果表明,基于TEA算法的地理信息数据加密技术可以有效实现地理信息数据的加密及解密处理,满足移动系统对地形数据的高安全存储和高性能处理的要求。 相似文献
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公共服务设施作为社区生活圈的核心内容,直接决定了社区生活圈的生活品质。对社区公共服务设施建设情况进行量化评价,并对设施建设的未来规划提供科学决策支持逐渐成为规划者和决策者的一大难题。本文通过ArcGIS工具对POI数据进行处理、统计和可视化,在总结他人社区生活圈量化评价方法的基础上,结合温州本地特色,搭建了一套社区生活圈公共服务设施评价模型。利用该模型可对各类社区进行综合评分和分级,并根据模型评分结果挖掘公共服务设施未来优化方向。此外,还实现了社区生活圈评分的动态计算与展示,为社区服务设施建设选址、路网建设与公共服务设施建设优先级评定等提供决策支持。既可帮助规划者和决策者快速建立对整个区域生活圈建设现状的量化认知,又可助力公共服务设施的优化配置,为社区生活圈公共服务品质评价与提升探寻全新的思路与方法。 相似文献
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《Geoforum》2014
Biosecurity, in broad terms, aims to reduce the impact and incidence of threats to life through regulatory means. For reasons we raise in this paper, such regulation can often lead to the specification of disease free processes within the food and farming industry, with biosecurity success measured in terms of the degree of compliance with and allegiance to modern farming practice. We counter this progressive narrative in three ways. First we draw on UK-based qualitative fieldwork with vets, farmers and pigs to demonstrate how biosecure farming and disease freedom are translated and qualified, in practice, to pathogen free, pathogen management and ultimately to configuring health through immunity management. Second, these translations demonstrate how building health is dependent on spatial and microbiological diversity rather than uniformity. Crucially, health involves patch-work and situated knowledge practices that are under threat within an industry increasingly marked by control and homogeneity. Third, in conceptual terms, we argue that while pig farming is organised through both biosecurity and a biopolitical regulation of life, immunity opens up political space for exploring an alternative politics of life, one where farmers and others are not so much made responsible for disease prevention, but make valued contributions to understandings of animal health and food security. 相似文献