一种顾及异常区域的海温多尺度分区方法

空间聚类分析是空间数据挖掘的主要方法之一,旨在发现海量数据中潜在的空间分布模式和异常特征。此处采用空间聚类分析和多尺度分析相结合的策略对海温进行多尺度气候分区。首先,针对气候时间序列特征和异常区域特征,提出一种顾及异常区域的多尺度分区方法;进而,分别采用传统方法和新方法对海温进行多尺度气候分区,通过比较分析发现新方法更优越;最后,利用气候指数对分区结果进行验证,说明新方法是有效的。

已建区排水管网评估及多尺度分区改造策略

为评估已建区现状排水管网情况并以问题为导向提出针对性的多尺度分区管网排水能力提升优化策略,以北京市东城区为例,构建基于InfoWorks ICM的城市综合流域排水模型,选用两场实测降雨分别进行参数率定及模型验证,结果表明模型具有较高的精度与可靠性。在此基础上,利用该模型对1a、3a、5a、10a四种不同设计重现期、历时1h降雨情景下的排水管网排水能力进行模拟,分三个尺度对研究区域模拟结果的分析如下:(1)城市尺度的管网排水能力不足1a一遇、1～3a一遇、3～5a一遇、5～10a一遇、10a一遇的管线长度比例分别为52%、10%、4%、6%、29%;(2)地块尺度功能分区排水能力排序为:公园绿地≥居民小区>商务行政办公区>商业区;(3)道路尺度的主次干道管线排水能力不足1a一遇、1～3a一遇、3～5a一遇、5～10a一遇、10a一遇的管线长度比例分别为38%、9%、4%、7%、42%。针对不同尺度下排水管网排水能力的现状评估结果,诊断并分析排水能力不足的问题及成因,以期通过系统性的管网现状评估及优化方案,为国内其他老城区的管网排水能力提升提供一套适用性的优化改造策略。

基于LBP和SVM的疼痛表情识别

对面部疼痛表情估计是疼痛评估中一条有效的途径,文中融合局部二元模式(LBP)分块加权和多尺度分区的特征提取方法用于面部疼痛表情识别.首先对预处理的图像在分块提取直方图后进行加权,然后采用多尺度分区直方图统计特征提取方法,串接不同尺寸分区块的直方图并级联分块加权的直方图为整个图像的特征向量,最后用主成分分析(PCA)的方法对特征向量进行降维后,输入支持向量机(SVM)进行分类识别,通过在自建的疼痛表情图像数据库进行实验,表明与传统的特征提取和融合前的特征提取方法相比,该方法能大大提高对疼痛表情的识别率,为目前对疼痛表情的识别与研究提供了一条有效的途径.

Optimum Solution for the Safe Drinking Water Crisis in Tala Upazila, Bangladesh

Coastal areas of Bangladesh are especially vulnerable due to their physiographic location and exposure to natural calamities. Around 35 million people living in coastal areas have no access or limited access to safe drinking water. Contamination of water sources by salinity, arsenic or iron are the principal causes of water scarcity. Rising sea levels and unevenness of climatic events due to climate change will exacerbate the situation in coastal areas, especially in the southwestern coastal zone. This study examines one of the vulnerable coastal upazila Tala at Satkhira(an 'upazila' is a medium level administrative unit in Bangladesh) in the southwestern zone of Bangladesh to understand the gravity of the problems. The study develops a GIS based multi-criteria analysis to identify suitable options and locations of fresh water as part of a current and future solution to the problems and further deterioration. To fulfill the objectives, a questionnaire-based GPS guided field survey was conducted to collect details of field level conditions in order to find a suitable solution. Because aquifers are considered the primary source of drinking water, field data have been analyzed for two distinct aquifers, one relatively shallow and one deeper, to understand aquifer quality. Potentiality of different water sources the socioeconomic status of communities, types of water use and corresponding sources and water demand are also evaluated. The analysis finds that alternative water sources that are safe are difficult to find, because both surface and groundwater-based sources are already contaminated, and there are no nearby, easily accessible safe sources. Groundwater-based sources are contaminated by arsenic, iron or salinity, and surface water-based sources are not in use due to maintenance and management issues. In some cases, surface water sources are polluted by flash flooding of high saline water during storm surges or seepage from saline water-based aquacultures. Multiple limitations identified during field observations and field data analysis were considered as an analytical parameter A GIS based multi-criteria analysis incorporated field data, including Geo-spatial and socioeconomic information for road networks, settlement locations, number of households, quality and quantity of existing water sources, water demand and business opportunities. The analysis found some potential options in distributed locations which are consistent with community demand. Suggested options made use of technologies that are already understood and commonly used by communities, like deep tubewells, PSFs(Pond Sand Filter) and WTPs(Water Treatment Plant). In the study area, PSF is the most commonly used method and to make this surface water-based technology sustainable some precautionary measurements are suggested.

Multi-scale chemo-mechanical analysis of the slip surface of landslides in the Three Gorges, China

Multi-scale chemo-mechanical effects and microscopic failure modes are explored in the evolution of strength change of slip surface. Direct shear equipments, scanning electro-microscope and X-ray diffraction are used to trace the change in strength of remodeled soils of slip surfaces in the Three Gorges area. Results show that there is a release of alkali metals and concentration of clay minerals on the surface. During the tests, potassium ions were released, the cementation was reduced, and the ratio of interlayer minerals varied associated with strength change. Accordingly, illites or montmorillonite-illite mixtures turned into montmorillonite. So the strength change originates from the release of alkali metal ions on molecular scale that leads to the concentration and transition of clay minerals on meso-scale. The evolution of slip surface and soil strength is a typical process involving multi-scale processes of structure changes and chemo-mechanical coupling.