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1.
Laboratory-based studies related to isolation and quantification of sediment and their properties which influence the spectral reflectance of sediment-laden waters were made. Some of these including the effects of sediment concentration, size variation, salinity, etc. have been published elsewhere. Using spectral reflectance measurements, properties of various soil types in a suspension can be inferred. The identification of dominant soil types present in a runoff water may help in the characterisation of the type of catchment area. The source of sediment load carried by the runoffs may also be predicted for future confirmation through the ground and geological surveys. Predictive models for evaluating soil properties alongwith steps to identify the dominant soil type(s) in a suspension are also presented.  相似文献   
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The study area is located near the town of Filippoi, north of the city of Kavala in northern Greece, known from ancient times for its rich gold mines, situated inside hydrothermal alteration zones (Fe–Mn oxide minerals). A Very High-Resolution (0.5 m pixel size) image of Worldview-2 satellite was digitally enhanced, yielding target areas of potential ore existence and lineaments. Ground-truth that followed digital image processing, revealed abandoned ancient mines, slags and ore occurrences. Also, a number of lineaments delineated on the satellite image were verified as faults.  相似文献   
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The cognition of thermal comfort plays a pivotal role in human life and activities. Recognizing thermal comfort based on climatic parameters is substantially significant. The main objective of the present study is to map thermal comfort using statistics from 43 meteorological stations, from 1970 to 2013. Initially, according to temperature and relative humidity, annual and seasonal thermal comfort conditions were mapped, and later bioclimatic human thermal comfort conditions in line with spatial factors were zoned based on bioclimatic indexes of Temperature Humidity Index (THI), effective temperature (ET) and Relative Strain Index (RSI). Among geostatistical methods, empirical Bayesian kriging (EBK) method with less RSME is more efficient. The annual distribution of temperature changes according to spatial factors of rugged topography and elevation, and latitude affects relative humidity. Thermal comfort in the northern and western half of Iran is higher than the southern and eastern areas of the country. Spatial factors of latitude and altitude reduce bioclimatic uniformity and create small areas with or without thermal comfort conditions. Bioclimatic indicators based on air temperature and relative humidity range of bioclimatic zones show. The results of ET and THI divide the whole country into six zones, from lack of thermal comfort to having thermal comfort conditions. Areas of southern strip as well as central and southeastern parts of the country do not have any human thermal comfort conditions in most of the year.  相似文献   
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近几十年,全球汇款流在稳步增长并越来越成为发展中国家财政发展的重要源泉。汇款成为家庭收入中稳定的一部分,并组成了发展中国家第二大资金流——处于外国直接投资(FDI)之后,海外开发援助(ODA)之前。在撒哈拉以南非洲地区,流动工人的汇款成为财政发展以及救助穷人的财政服务的重要主题。本论文分析撒哈拉以南非洲地区迁移人口的汇款及其作用,并以马里作为重点研究对象。研究结论是,汇款在国家收入中占有重要比例,并将继续对个人家庭和社区提供重要支持,应该鼓励当地引导汇款促进基础设施发展和收入产生。  相似文献   
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With regard to the lack of quality information and data in watersheds, it is of high importance to present a new method for evaluating flood potential. Shannon’s entropy model is a new model in evaluating dangers and it has not yet been used to evaluate flood potential. Therefore, being a new model in determining flood potential, it requires evaluation and investigation in different regions and this study is going to deal with this issue. For to this purpose, 70 flooding areas were recognized and their distribution map was provided by ArcGIS10.2 software in the study area. Information layers of altitude, slope angle, slope aspect, plan curvature, drainage density, distance from the river, topographic wetness index (TWI), lithology, soil type, and land use were recognized as factors affecting flooding and the mentioned maps were provided and digitized by GIS environment. Then, flood susceptibility forecasting map was provided and model accuracy evaluation was conducted using ROC curve and 30% flooding areas express good precision of the model (73.5%) for the study area.  相似文献   
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The potential of the autoclaved Tunisian landfill leachate treatment using microalgae (Chlorella sp.) cultivation was investigated in this study. Landfill leachate was collected from Borj Chakir landfill, Tunisia. A full factorial experimental design 22 was proposed to study the effects of the incubation time and leachate ratio factors on the organic matter removal expressed in chemical oxygen demand (COD) and ammoniacal nitrogen (NH4─N) and on the biological response of Chlorella sp. expressed by the cell density and chlorophyll content. All experiments were batch runs at ambient temperature (25 ± 2 °C). The Chlorella sp. biomass and chlorophyll a concentrations of 1.2 and 5.32 mg L?1, respectively, were obtained with 10% leachate spike ratio. The obtained results showed that up to 90% of the ammoniacal nitrogen in landfill leachate was removed in 10% leachate ratio spiked medium with a residual concentration of 40 mg L?1. The maximum COD removal rate reached 60% within 13 days of incubation time indicating that microalgae consortium was quite effective for treating landfill leachate organic contaminants. Furthermore, with the 10% leachate ratio spiked medium, the maximum lipid productivity was 4.74 mg L?1 d?1. The present study provides valuable information for potential adaptation of microalgae culture and its contribution for the treatment of Tunisian landfill leachate.  相似文献   
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当代非洲城市化的动因与困境   总被引:1,自引:0,他引:1  
非洲的城市人口已经正在以年均超过4%的增长率增长,居世界首位,其中个别城市甚至还要高。对文献的回顾显示,贫困、非正规经济或类似经济的增长与发展已经成为撒哈拉以南非洲国家城市化的一个不可分割的部分。结论是快速城市化是非洲政府所面临的最紧迫的管理挑战。并且,要在致力于解决当前问题的同时,创造使城市成为经济增长和发展的更有效中心的政策环境。城市必须是可控制的、适于居住的、以及经济上可望成功的。  相似文献   
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Natural Hazards - The western Makran subduction zone is capable of producing considerable tsunami run-up heights that penetrate up to 5 km inland. In this study, we show how climate change...  相似文献   
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Acta Geochimica - The Dibdibba aquifer is considered to be the main source in the Al-Zubair area because agriculture depends on it to provide grazing water in the area. The groundwater well samples...  相似文献   
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