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301.
302.
Landfill site selection by decision-making tools based on fuzzy multi-attribute decision-making method 总被引:2,自引:2,他引:0
Abdolhadi Nazari Mohammad Mehdi Salarirad Abbas Aghajani Bazzazi 《Environmental Earth Sciences》2012,65(6):1631-1642
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
303.
304.
A comprehensive seismic risk assessment has been performed for the existing route of the 3rd Azerbaijan natural gas buried pipeline in Iran. The major active seismic sources along the pipeline were identified and the geometrical parameters as well as the seismicity rates were determined. The seismic hazard assessment of the ground vibrations along the pipeline was performed in the framework of the Probabilistic Seismic Hazard Analysis using the CRISIS 2007 software. All of the components of the gas pipeline along the route were identified and the corresponding fragility functions are established through the methodology described in the HAZUS guideline (HAZUS MH MR4 Technical manual 2007 Department of homeland security emergency. Preparedness and Response Directorate, FEMA). A detailed cost analyses was taken into consideration based on the expert opinions in the National Iranian Gas Company, in order to provide more practical loss model for the pipeline route. Also, a simple method is suggested in order to account for the vent gas in the total loss estimation. The spatial analysis of the hazard function layer in combination with the loss model layer, in Geographical Information System (GIS) platform, reveal the financial consequences of different earthquake scenarios. 相似文献
305.
China Ocean Engineering - The breakwaters have experienced many changes during their construction history. These changes have been considered to improve their performance, depending on their... 相似文献
306.
Mehdi Bolouki Kourandeh S. Mohammad Bagher Nabavi Mahmood Sinaei 《Ocean Science Journal》2013,48(3):251-258
In this study, Zooxanthellae density, chlorophyll a concentration, and mitotic index (MI) were measured in the coral Porites compressa obtained from coastal areas of the Persian Gulf in early February to September 2008. During the summer, zooxanthellae density declined by approximately 30% compared to the winter peak (3,607,849 ± 229,894, n = 15) and reached a minimum of 2,536,732 ± 169,776, n = 15. The highest value of chlorophyll a (0.828 ± 0.043 μg/cm2) was recorded in the south while the lowest (0.604 ± 0.048 μg/cm2) was measured in the north sampling site at the cold season. There was a higher level of MI in the warm season followed by cold > and temperate seasons. The MI were significantly higher (p < 0.05) in the warm and cold seasons in comparison with the temperate season. Differences in response may be attributed to the drastic seasonal temperature changes. However, the significant decline found in the north sampling site indicates that anthropogenic stressors may adversely affect coral P. compressa. These results imply that there were negative impacts on coral P. compressa in our study site. 相似文献
307.
Fe and Al oxides distribution in some ultisols and inceptisols of southeastern Nigeria in relation to soil total phosphorus 总被引:3,自引:1,他引:2
Ten highly weathered soils in southeastern Nigeria were sampled from their typical A and B horizons for analyses. The objectives
were to determine the different forms of Fe and Al oxides in the soils and relating their occurrence to phosphate availability
and retention in the soils. The soils are deep and often physically degraded but are well drained and coarse in the particle
size distribution. They are mostly dominated by kaolinite in their mineralogy with very high values of SiO2. The soils are acidic with low soil organic carbon (SOC) contents. The elements in the exchange complex are also low thus
reflecting in the low CEC of the soil. Available phosphorus (P) in the soils are generally low while total P ranged from 157
to 982 mg kg−1 with an overall average of 422 mg kg−1. Total Fe in the soil is highest and their order represented as follows: Fet > Fed > Feox ≥ Fep. The pyrophosphate extractable Fe was always higher in the top soil than in the subsoil and was attributed to the fact that
these forms of Fe are associated with organic matter which is more abundant in topsoil than in subsoil. Like in Fe forms,
the order of Al occurrence could generally be presented as; Alt > Ald > Alox > Alp. More Fe and Al oxides in the soils are strongly crystalline while a small quantity is poorly crystalline Fe forms. The amorphous
forms of both Fe and Al are very low in the soils when compared with the crystalline forms. The oxides that show very strong
affinity to total P are Fed–Feox, Fed, Ald, Fet, Feox and Alox/Ald. To overcome this problem of P retention in the soil, we recommend constant liming of these soils to neutralize them, application
of organic matter and of high dosage of phosphate fertilizer to the soils. 相似文献