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61.
Selection of wastewater treatment process based on the analytical hierarchy process and fuzzy analytical hierarchy process methods 总被引：2，自引：1，他引：1
A. R. Karimi N. Mehrdadi Ph.D. S. J. Hashemian G. R. Nabi Bidhendi R. Tavakkoli Moghaddam 《International Journal of Environmental Science and Technology》2011,8(2):267-280
This paper presents an application of the analytical hierarchy process and fuzzy analytical hierarchy process methods for selecting the best wastewater treatment process. The analytical hierarchy process is one of the best ways for deciding among the complex criteria structure in different levels, and the fuzzy analytical hierarchy process is a synthetic extension of the classical method when the fuzziness of the decision makers are considered. After reviewing aerobic treatment processes operated in Iran’s industrial estates and determining the main criteria used for treatment process evaluation, they are arranged in a hierarchy structure. Selection of the best wastewater treatment process is a multi-criteria decision making problem. Conventional methods are inadequate for dealing with the imprecise or vague nature of linguistic assessment. To overcome this difficulty, the fuzzy analytical hierarchy process is proposed for dealing with the vagueness of decision makers’ judgments. The alternatives consist of extended aeration, absorption bio-oxidation, integrated fixed-film activated sludge, sequencing batch reactor, aerated lagoon. Based on the general condition of industrial estate’s wastewater treatment plants, technical/administrative, economic and environmental criteria and their sub-criteria are weighted and then criteria evaluated and priorities of alternatives have been done by analytical hierarchy process and fuzzy analytical hierarchy process methods by the use of triangular fuzzy numbers. Finally, selection of the best process and ranking of these five processes are carried out by these foregoing methods, and some sensitivity analyses are conducted to show the results’ sensitiveness to the changes of the weights of the evaluation criteria. 相似文献
62.
Most approaches in statistical spatial prediction assume that the spatial data are realizations of a Gaussian random field.
However, this assumption is hard to justify for most applications. When the distribution of data is skewed but otherwise has
similar properties to the normal distribution, a closed skew normal distribution can be used for modeling their skewness.
Closed skew normal distribution is an extension of the multivariate skew normal distribution and has the advantage of being
closed under marginalization and conditioning. In this paper, we generalize Bayesian prediction methods using closed skew
normal distributions. A simulation study is performed to check the validity of the model and performance of the Bayesian spatial
predictor. Finally, our prediction method is applied to Bayesian spatial prediction on the strain data near Semnan, Iran.
The mean-square error of cross-validation is improved by the closed skew Gaussian model on the strain data. 相似文献
63.
F. Rouhollahi A. Zamani K. Karimi N. Etesami 《International Journal of Environmental Science and Technology》2014,11(7):1911-1918
Enzymatic and alkali pretreatments were employed to improve nickel biosorption capacity of Rhizomucor pusillus biomass. Pretreatment with 0.002–80 g l?1 NaOH and 0.0001–0.1 Anson Unit (AU) g?1 protease enhanced the biosorption capacity of fungal biomass. Increasing the concentration of NaOH from 0.002 to 5 g l?1 improved nickel removal from 93.2 to 100.0 % while untreated biomass showed 64.6 % Ni(II) removal. Pretreatment with higher concentrations of NaOH, 5–80 g l?1 resulted in nearly complete removal of nickel ions. Pretreatment of the biomass with 0.0001 AU g?1 protease improved the nickel removal to over 91 %, while increasing the enzyme loading to 0.1 AU g?1 improved the removal to 93 %. Untreated biomass removed 78.4, 63.0, and 96.3 % of chromium, copper, and lead ions, respectively, from a mixture solution of the ions. Respective metal removals were increased to 100, 98.9, and 100 % after pretreatment with 0.2 g l?1 NaOH solution and to 87.8, 86.7, and 100 % after the enzymatic pretreatment with 0.1 AU g?1 protease. Scanning electron microscopy analysis indicated that alkali and enzymatic pretreatments enhanced the porosity of the biomass. Furthermore, compositional analysis showed that both of the pretreatments removed a major part of fungal proteins (2.1–95.8 % removal). Glucosamine, N-acetyl glucosamine, and phosphates were the major ingredients of the pretreated biomass. 相似文献
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K. D. Bastami M. Taheri H. Bagheri M. Y. Foshtomi S. Ganji S. Haghparast F. Soltani A. Hamzehpoor B. Karimi 《International Journal of Environmental Science and Technology》2014,11(7):2025-2036
This study aimed to investigate the population of annelida communities in relation to environmental factors and heavy metals accumulated in sediments of the Gorgan Bay. The pollution load index and potential ecological risk (PER) were calculated. The results indicated mean concentrations (ppm) of heavy metals were (mean ± SD) Pb: 11.5 ± 4.88, Cu: 18 ± 8.83, Zn: 42 ± 22.15, Ni: 29.20 ± 14.68, Co: 10.56 ± 14.68, As: 7.77 ± 2.12, Sr: 1,449 ± 902.59 and V: 26.64 ± 10.25. Considering PER, sediments of the Gorgan Bay had low ecological risk. Based on abundance data, dominant species were Streblospio gynobranchiata, Nereis diversicolor, Tubificoides fraseri and Tubificidae unknown, respectively. Results of redundancy analysis displayed that T. fraseri and N. diversicolor were associated with high values of Sr. All the species were negatively correlated with As. There were positive correlation between S. gynobranchiata and N. diversicolor with values of clay, salinity, depth and silt. The present study provided the relative importance of heavy metals and environmental variables which partly assist in structuring assemblages of annelida in a transitional area. 相似文献
65.
Hossein?Karimi VardanjaniEmail author Manouchehr?Chitsazan Derek?Ford Haji?Karimi Abbas?Charchi 《Hydrogeology Journal》2018,26(1):57-70
Sousan Spring emerges from the Keyno Anticline, Zagros Mountains (Iran), and the mean annual discharge is ~24 m3/s. Geological and hydrochemical evaluations suggest that the spring recharge is from the limestone Ilam-Sarvak Formation (Cretaceous) but the Mafaroon Fault, a major thrust feature, influences the regional groundwater flow path by juxtaposing other strata. Geological, geochemical, stable isotope and water balance studies were employed to interpret this behavior. Using the isotope data, the sources and elevations of the recharge area were found. Temporal variations of the isotopic data were compared with variations of electrical conductivity (EC). Unexpectedly, high EC was associated with a relative increase of discharge and depletion of δ18O. Several hypotheses were investigated and approximate water balance studies employed for validation. It was found that an elongated catchment on the Keyno Anticline plus a lesser catchment on a pair of parallel anticlines recharge the aquifer. While the long groundwater flow path along the Keyno Anticline plus guidance by Mafaroon Fault and the adjacent Garou shaly strata lead to increased EC in the Sousan Spring at the end of the dry season, a flow pulse from two adjoining anticlines (Mahalbakh and Shirgoon) arrives at the same time to increase the discharge and deplete the δ18O signal. Apparently the spring did not experience true base flow conditions during the recorded hydrological year. Although the spring response to specific precipitation events was similar to typical karst aquifers, standard interpretation of recession curves and related coefficients will not be practical at Sousan. 相似文献
66.
Characterising the main karst aquifers of the Alvand basin, northwest of Zagros, Iran, by a hydrogeochemical approach 总被引：1，自引：0，他引：1
The Alvand River basin, situated in the northwest of the Zagros mountain range, Iran, drains carbonate aquifers through some important karst springs. The physical, chemical and isotopic characteristics of spring water were studied for two years in order to assess the origin of groundwater and determine the factors driving the geochemical composition. Principal components analysis was used to identify the main factors controlling the water chemistry. Two groups of springs were identified: (1) low mineralisation, ion concentration, especially sulphate, low temperature, light isotope composition and high elevation of the recharge area, and (2) moderate to high mineralisation, especially sulphate, higher temperature, heavy isotope composition and low altitude of the recharge area. The main factors controlling the groundwater composition and its seasonal variations are the geology, because of the presence of evaporite formations, the elevation and the rate of karst development. In both groups, the carbonate chemistry is diagnostic of the effect of karst development. The supersaturation with respect to calcite indicates CO2 degassing, occurring either inside the aquifer in open conduits, or at the outlet in reservoirs. The undersaturation with respect to calcite shows the existence of fast flow and short residence-time conditions inside the aquifer. A PCA analysis showed that, contrary to most developed karst systems, where dilution occurs during the wet season, leaching of the gypsum-bearing Gachsaran Formation by rainwater produced higher mineralisation.
Resumen La cuenca del río Alvand, situada en el noreste de la cadena montañosa Zagros drena acuíferos compuestos por carbonatos a través de manantiales kársticos. Durante dos años se estudiaron las características físicas, químicas e isotópicas del agua de manantial con el objetivo de determinar el origen del agua subterránea y de los factores que controlan su composición geoquímica. Se utililizó el análisis de componentes principales para identificar los factores principales que controlan la química del agua. Se identificaron dos grupos de mantaniales: (1) de baja mineralización, concentración de iones especialmente sulfatos, y baja temperatura, composición de isotopos livianos y elevación alta del área de recarga, y (2) mineralización moderada y alta, especialmente, sulfatos, y temperatura más alta, composición de isotopos pesados y altitud más baja del agua de recarga. Los factores principales que controlan la composición del agua subterránea y sus variaciones estacionales son la geología debido a la presencia de formaciones evaporitas, la elevación y la tasa a la que se desarrolla el karst. En ambos grupos la química de los carbonatos es un diagnóstico del efecto del desarollo de la estructura kárstica. La supersaturación con respecto a la calcita indica presencia de CO2 que está en proceso de degasificación que ocurre dentro de acuífero en conductos abiertos o a la salida en reservorios. La subsaturación en lo referente a la calcita muestra la existencia de flujo rápido y de tiempos cortos de residencia al interior del acuífero. El análisis de componentes principales muestra que a diferencia de la mayor parte de sistemas kársticos en donde la dilución ocurre durante la temporada de lluvias, la lixiviación de la formación Gachsaran que contiene yeso a causa de lluvia produce mineralizaciones más altas.
Résumé Le bassin de la rivière Alvand, situé dans le nord-ouest de la chaîne de montagne Zagros, draine des aquifères carbonatés par le biais dun important réseau de sources karstiques. Les caractéristiques physiques, chimiques et isotopiques de leau provenant des sources ont été étudiées pendant deux ans afin de déterminer lorigine de leau souterraine et les facteurs responsables de sa composition chimique actuelle. Lanalyse des éléments chimiques majeurs a été utilisée pour identifier les processus qui contrôlent la composition chimique de leau. Deux groupes différents de sources ont été identifiés: (1) faible minéralisation et concentration en ions, spécialement en sulfates, faible température, composition isotopique légère et haute élévation de la zone de recharge, et (2) minéralisation moyenne à élevée, particulièrement en sulfates, température élevée, composition isotopique lourde et plus basse altitude de la zone de recharge. Les facteurs principaux qui contrôlent la composition et la variation saisonnière de leau souterraine sont la géologie, en raison de la présence dévaporites, lélévation et le taux de développement des karsts. Dans les deux groupes, la teneur en carbonates est un diagnostic de leffet du développement de la structure des karsts. La sursaturation par rapport à la calcite indique un dégazage en CO2 qui a lieu soit à lintérieur de laquifère, dans les conduits ouverts, ou à sa sortie, dans les réservoirs. La sous-saturation par rapport à la calcite indique lexistence dun écoulement rapide et un faible temps de résidence dans laquifère. Une analyse des éléments chimiques majeurs a démontré que contrairement aux systèmes de karst les mieux développés où la dilution a lieu lors de la saison humide, le lessivage du gypse de la formation de Gachsaran par leau de pluie produit une minéralisation plus élevée.相似文献
67.
In this article we present a heuristic map simplification algorithm based on a novel topology‐inferred graph model. Compared with the existing algorithms, which only focus either on geometry simplification or on topological consistency, our algorithm simplifies the map composed of series of polylines and constraint points while maintaining the topological relationships in the map, maximizing the number of removal points, and minimizing error distance efficiently. Unlike some traditional geometry simplification algorithms, such as Douglas and Peucker's, which add points incrementally, we remove points sequentially based on a priority determined by heuristic functions. In the first stage, we build a graph to model the topology of points in the map from which we determine whether a point is removable or not. As map generalization is needed in different applications with different requirements, we present two heuristic functions to determine the priority of points removal for two different purposes: to save storage space and to reduce computation time. The time complexity of our algorithm is which is efficient enough to be considered for real‐time applications. Experiments on real maps were conducted and the results indicate that our algorithm produces high quality results; one heuristic function results in higher removal points saving storage space and the other improves the time performance significantly. 相似文献
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The challenge of making the transition to a sustainable energy regime is not limited to engineering; it has important social and political dimensions. Therefore, implementation of new technologies, such as carbon capture and storage (CCS), requires not only economic and technical capacities but also an understanding of social factors. These factors include experts’ views and risk perceptions. Understanding them will contribute to the risk governance of CCS by demonstrating who is concerned about what and why with respect to CCS and how risk perception and stakeholders’ concerns vary in different countries. This research is based on analysis and mapping of data collected from case studies of three countries: Germany, Norway and Finland. Our analysis shows that in countries where opposition to CCS is the strongest, like Germany, risk perceptions can be driven by such factors such as the lack of trust and doubts about the need of the project. At the same time as in countries with moderate opposition, such as Norway or Finland, risk perceptions are more connected with the risk for investment. We also conclude that the strongest polarization in risk perceptions is among NGOs in different countries, followed by scientists. The positions of private sector stakeholders and government are more homogenous. Such large variation in risk perceptions of experts could be influenced by several factors, including cultural orientation, attitudes and views of stakeholders, and the social, political and technical settings for deployment of technology in each country. 相似文献