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621.
A non-parametric method for supervised pattern recognition is presented. The method is of the classmodelling type, meaning that a classification rule is developed for each class, using the dissimilaritiesbetween the objects of the class. The dissimilarities between the objects within a class are related to thedistances between all pairs of training objects. As distance metric, a measure is proposed that takes thecorrelation between the interval-scale variables into account, and that moreover can be used for mixedtypes of variables. The classification rule is based on the construction of a boundary in the measurementspace. For the determination of the class boundary, several strategies are proposed and compared. The performance of the technique is evaluated on the basis of several data sets. Comparison with theclass modelling technique UNEQ shows its usefulness for practical applications. 相似文献
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624.
城市景观格局动态及其规划的生态学探讨 总被引:10,自引:2,他引:10
城市作为人类的主要栖居地,其景观格局和生态效应直接影响到世界人口的生存质量。从景观生态学的视角出发,以国内外近年来关于城市景观格局动态及其生态效应的理论和实证研究为材料,整理并总结了城市景观格局的特征、研究方法和演变机制。在文献综述和具体案例分析的基础上,尝试性地提出城市景观格局动态的“类库兹涅茨曲线”现象,即在从城市化初期到城市发展相对成熟的一个周期内,景观破碎化程度呈现“快速增加—增速减缓—平稳下降”的过程,并探讨了这一规律的适用性和特征。在此基础上,进一步讨论了城市景观及其格局变化对生态环境的影响,指出在城市景观规划中充分结合生态学原理,是实现城市可持续发展的必经之路。 相似文献
625.
The traditional use of land for food, fuel and wood created cultural landscapes, which are threatened across Europe. The factors which contributed to their endangerment need to be identified to achieve effective preservation of such landscapes. The aim of our study was to identify landscapes with historical persistence in a GIS-based comparative analysis of historical and contemporary maps and the most prominent causes of the past landscape changes, based on stakeholders' perspective. We considered a case study in Romania's Carpathians. Three major land cover types were extracted from maps dating from 1912, 1980 and 2009: built-up, pastures and forests. The historical persistence of all land cover types was poor (<20%) and profound changes were quantitatively confirmed. Large, compact patches of unchanged forests were located in the neighbourhood of a national park. The persistent pastures were situated close to human settlements, and their preservation can be related to local traditional agro-silvo-pastoral management. Although the built-up area has increased over time, the corresponding surfaces are small and consist of scattered patches located around historical monuments. Semi-structured interviews were conducted to investigate stakeholders' perspective. Using cluster analysis five prominent causes of past landscape changes are identified: 'increasing tourism', 'land tenure and social changes', 'land-use intensification', 'post-communist transition', and 'foreign investments'. We join the results of the GIS analysis with those from stakeholders' perspective to gain more insights into the landscape changes. This research offers important information that could be used for the further planning of these valuable cultural landscapes in order to avoid potential conflicts and degradation. 相似文献
626.
《Geoforum》2014
Political memories—which are crucial for establishing and maintaining ‘political capital’, based on individual and group positioning during past conflict and wars, but also in relation to presentday politics—are important when considering varied outcomes from negotiations and other interactions that occur in the Lao People’s Democratic Republic in relation to large-scale economic land concessions. This paper continues to expand on the idea of political memories of past conflicts and wars by considering the concept in relation to the theoretical framework proposed by Hall et al. (2011) in their book Powers of Exclusion, which stresses the importance of interactions between regulation, force, the market and legitimation for understanding different types of exclusionary processes, especially those linked to land access. I argue that political memories are particularly relevant when it comes to legitimation, but that expanding the concept so as to include political memories is important. In relation to large-scale plantation, mining and hydropower dam concessions, I also stress the importance of political memories in (re)shaping understandings of landscapes, thus creating particular varieties of memory laden political landscapes, which too are constituted by the past but are also politically mobilized in the present. 相似文献
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628.
文章从辽东半岛南部石英岩板岩区地下水富水不均的特点出发,论述了基岩地下水富集规律:贮存在蓄水构造中,汇集在集水网络里,运移富集在充水脉络交接、结点处。进一步对水文物探各类富水曲线进行了分类,概括富水异常特征。结合多年实际勘测成果,论证了依据“结点异常”确定富水点位。 相似文献
629.
Bayes方法及其在地震预报中的应用 总被引:1,自引:0,他引:1
对Bayes方法进行了分析并将其应用于华北地区强震的预测,结果较好。内符合检验、阈值试验、FH检验、时间窗移动试验等一系列控制试验表明识别结果较稳定。 相似文献