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251.
Landfill site selection is a complex and time-consuming process, which requires evaluation of several factors where many different attributes are taken into account. Decision makers always have some difficulties in making the right decision in the multiple attribute environments. After identifying candidate sites, these sites should be ranked using decision-making methods. This study applies Chang’s fuzzy AHP-based multiple attribute decision-making (MADM) method for selection of the best site of landfills based on a set of decision criteria. The Fuzzy Analytic Hierarchy Process (FAHP) was designed to make pairwise comparisons of selected criteria by domain experts for assigning weights to the decision criteria. Analytic Hierarchy Process (AHP) is used to make pairwise comparisons and assign weights to the decision criteria. It is easier for a decision maker to describe a value for an alternative by using linguistic terms and fuzzy numbers. In the fuzzy-based AHP method, the rating of each alternative was described using the expression of triangular fuzzy membership functions. Once the global weights of the criteria is calculated by AHP, they are incorporated into the decision matrices composed by decision maker and passed to fuzzy-AHP method which is used to determine preference order of siting alternatives. In this study, a computer program based on the Chang’s fuzzy method was also developed in MATLAB environment for ranking and selecting the landfill site. As an example of the proposed methodology, four different hypothetical areas were chosen and implemented to demonstrate the effectiveness of the program. By using this program, the precision was improved in comparison with traditional methods and computational time required for ranking and selecting the suitable landfill site was significantly reduced.  相似文献   
252.
Dust storms loads analyses—Iraq   总被引:1,自引:1,他引:0  
The dust storms that blow over Iraq were studied from December 2008 to March 2009. The total number of studied dust storms was eight; during each dust storm, samples were collected from the cities of Baghdad, Ramadi, Kut, Basra, Najaf, Karbala, Hilla and Tikrit. The climatic elements with the dust storms types were studied. The results of dust storms analyses reflect their increase in average toward the southwestern direction (average suspended, rising, regional dust storms were 8, 10, 15 days/year, respectively). The average means annual rainfall (in mm), evaporation (in mm), temperature (in °C), and relative humidity percentage indicate that there were remarkable variations in values, with increase of the number of days/years of the dust storms reflecting the effect of the regional climatic change. The results of particle size analyses indicate the texture of most samples range from sandy clayey silt (75%) and clayey sandy silt (25%), and the average dominant grain size have a direct relationship with trajectories of dust storms. Quartz grains were 15% rounded and 85% sub-rounded. Moreover, the dust samples were analyzed and identified by using XRD analyses and Polaroid microscope. The results reflect the following minerals according to their average relative dominant, quartz 58.6%, feldspars 17.3%, and calcite 15.4%, with small amount of gypsum 5.5%. The clay minerals (chlorite, illite, montmorillonite, palygorskite, and kaolinite) were recognized. The analyses of heavy minerals percentages by using the microscope were performed. The results of pollen distribution, in descending order, were Chenopodiaceous, Graminea, Pine, Artemisia, Palmae, Olea, and Typha (reaching 79%, 69%, 63%, 53%, 17%, 9%, and 7% of the counted pollen grains, respectively). The results of microorganisms (i.e., isolated bacteria and fungi), in descending order, were the gram-positive Bacillus species (42.9%), Aspergillus species plus Candida albicans (13.8%), and (8.4%), the gram-negative rods, Escherichia coli (9.5%), the gram-positive Cocci streptococcus pneumonia (6.7%), then the gram-negative rod Enterobacter cloacae (4.3%), Staphylococcus epidermidis, and Staphylococcus (3.9%) and (1.9%). The remaining Gram-negative microorganisms were Pseudomonas aeruginosa (2.7%). Regarding the viral etiology, there is no viral isolate among the work results. The allergens commonly associated with dust storms include fungal spores, plant and grass pollens, and organic detritus represent agricultural area pollen grains.  相似文献   
253.
Groundwater contamination is one of the most significant problems in arid countries. Al-Quwiy’yia region is an example of an area where the groundwater is contaminated as a result of infiltration of waste water in low-lying areas adjacent to inhabited zones. Such contamination poses significant environmental threats for the surrounding environment and groundwater. Surface observations and spatial distribution of contamination observed in the shallow aquifer indicate that the main contamination sources were from sewage as well as from waste water dumping. However, the main source of water supply for the whole area is groundwater abstracted from the relatively shallow aquifer. Therefore, the transient electromagnetic method (TEM) and 2D electrical resistivity tomography (2D ERT) have been applied close to the waste water dump site to characterize the response of pollution plumes. Both of these geoelectrical techniques are sensitive to electrical conductivity as well as to other physical properties, which are greatly influenced by the polluted groundwater. Therefore, it is possible to profile the contamination plumes, both vertically and horizontally, in the vicinity of the measured stations. The ERT profiles gave detailed information about the lateral distribution of the contaminated groundwater, whereas the TEM demonstrated the vertical extensions.  相似文献   
254.
In biostratigraphic studies of the Surgah formation in the Kuh-e-Surgah section, 145 samples were collected. The thickness of the Surgah formation is about 175 m, and it consists mainly of limestone and shale. The lower and upper boundaries of the Surgah formation are Sarvak and Ilam formations, respectively, and they are conformable with sharp lithology. Seventeen species which belong to six genera of planktonic foraminifera and four biozones have been identified in this study. Based on foraminifera assemblages and biozone determinations, the age of the Surgah formation is Late Turonian to Early Late Santonian. This section is correlated with the Tang-e-Gerab section.  相似文献   
255.
This paper is devoted to study the dynamics of gravitational collapse in the Misner and Sharp formalism. We take non-viscous heat conducting charged anisotropic fluid as a collapsing matter with cylindrical symmetry. The dynamical equations are derived and coupled with the transport equation for heat flux obtained from the Müller-Israel-Stewart causal thermodynamic theory. We discuss the role of anisotropy, electric charge and radial heat flux over the dynamics of the collapse with the help of coupled equation.  相似文献   
256.
TISS: a decision framework for tailing impoundment site selection   总被引:1,自引:1,他引:0  
Tailing dam is one of the most important mining operations interface with surrounding environment even as long as many years after ore reserve exhausted. Therefore, appropriate design and management respect to future limitations of environmental regulations is required. Recently, effect of multiple criteria on tailing impoundment site selection makes it complex as the conventional procedures unable to answer. The systematic approach of multi attribute decision-making helps decision-makers select the most preferable decision and provide the basis of a decision support system. This paper developed new strategy based on fuzzy multi attribute group decision-making methods including: technique for order preference by similarity to ideal solution and analytical hierarchy process in fuzzy group environment. A hypothetical case is processed to demonstrate the strategy’s efficiency and results are compared and ranked so that the most preferable option is identified.  相似文献   
257.
Chott El Jerid in the Zone of Chotts of Tunisia is one of the largest endorheic basins in the world. During the dry period, from May to August, it is generally covered by continental evaporites which result from the desiccation of the lake formed after a flooding event. This lake comprises runoff water from the surrounding relief and also water resurgence. In order to map and monitor these evaporitic surfaces (mineral composition and evolution in space and time), optical multisource, multispectral, and multidate satellite data have been used. Landsat 4–5 TM, Landsat 8 OLI, SPOT 6, and Landsat Surface Reflectance (LSR) constitute the main data set. The central part of the Chott, north and south of the road crossing the Chott over 70 km from Tozeur to Kebili, has been particularly studied, because it corresponds to the major evaporite accumulation zone. These evaporites precipitated as concentric layers (a relatively rare pattern), mainly north of the road, after several recent flooding events during the last 15 years. Winds can play a significant role in the development of the evaporite layers. Image interpretation associated with field data shows that after the final desiccation of the playa lake, the mineralogy of the salt crust comprised an assemblage dominated by halite south of the road and by gypsum north of the road. Halite and gypsum are the only minerals to be identified using satellite remote sensing data. Sulfates such as gypsum can be identified thanks to a drop in reflectance in the short-wave infrared (SWIR) range caused by vibrations of the SO4 group. Gypsum crusts are more widely distributed than halite crusts. LSR data are particularly suitable for multitemporal comparison because they are calibrated and atmospherically corrected. The classical bull’s eye pattern characterizing evaporitic deposits (from carbonates along the rims to halite, gypsum, and finally potassium-magnesium minerals in the center of the basin) is deeply disturbed by the road crossing Chott El Jerid.  相似文献   
258.
摘 要:开展塔克拉玛干沙漠沙垄起伏地形夏季地表温度观测试验,旨在为塔克拉玛干沙漠环境陆面过程研究提供科学依据。2019年6月7日至9月2日在塔中地区,沿沙垄迎风坡以及背风坡底部、中部、上部、顶点及垄间谷地共设8个地表温度观测点。结果表明:(1)夏季沙垄地表温度最高温出现在垄间谷地,为74.63 ℃,最低温出现在迎风坡底部,为10.52 ℃;地表温度一天中在7:00左右达到最低,15:00左右达到最高。(2)晴天、多云以及浮尘天各观测点地表温度日均变化曲线呈单峰型,降水、扬沙及沙尘暴天呈双峰型;地表温度的最高温与日均值最大值均出现在晴天的垄间谷地,地表温度的最低温及日均值最小值均出现在降水天的迎风坡底部。(3)沙垄顶点与两个底部最大温差范围是顶点与背风坡底部在晴天的温差范围,为0~18.62 ℃,最小温差范围是顶点与迎风坡底部在降水天的温差范围,为0.01~6.18 ℃;迎风坡和背风坡在晴天地表温度温差范围最大,为0.01~16.93 ℃,在降水天温差范围最小,为0.01~4.15 ℃;顶点与两个底部夏季综合温差范围在0~18.62 ℃,迎风坡与背风坡夏季综合温差范围为0~16.93 ℃。塔克拉玛干沙漠地表温度受典型天气影响变化类型多样,沙垄顶点与底部、迎风坡与背风坡地表温度差异受风力及地形作用明显。  相似文献   
259.
基于巴基斯坦不同气候区4个代表站(卡拉奇、雅各布阿巴德、奎达、德罗什)1979—2018年地面观测资料和ERA-Interim气温资料,利用一元线性回归、Mann-Kendall突变检验和Morlet小波分析,分析其气温时空变化特征。结果表明:(1)巴基斯坦过去40 a经历了先降温后增温的过程,除北部山区年平均气温增温趋势显著,四季总体都有增温,春秋两季增温趋势显著。巴基斯坦于1998年左右发生气温突变,年平均气温存在4~5、12、20~22和32 a的周期。(2)ERAInterim再分析资料与地面观测数据拟合分析显示两者相关性达到极显著水平,除北部山区外,在大部分区域误差较小,能够较好地反映巴基斯坦气温的变化特征。(3)巴基斯坦年、季平均气温空间分布地带性明显,高温区位于南部印度河平原、三角洲地区,低温区分布在北部山区,年、春季、秋季平均气温变化在空间上总体均呈现明显增长趋势.  相似文献   
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