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21.
In this study, environmental impacts of industrial waste disposal of used lubricating oils and sulphur wastes scenarios have been investigated and modeled. The life-cycle assessment methodology was selected among the environmental impact assessment methods. In this method environmental issues and burdens were quantitated in order to facilitate the comparison. In this regard, options with the least adverse impacts were suggested. Functional unit of the study has also been defined as amount of used lubricating oils and sulphur wastes in terms of kilograms based on capacity of transitional barrel. Accordingly, the system boundaries were selected for life cycle of the wastes produced in sulphur unit of Tehran Oil Refinery. Since the main disposal method applied in Tehran Oil Refinery was transference to the municipal landfill, two incineration and landfilling scenarios were modeled for used lubricating oils and sulphur wastes by means of Simapro-7.1 software. Then, the outputs of these scenarios were compared in terms of the least environmental impacts by EDIP 2003 and Ecoindicator 99 methods. Finally, incineration scenarios were recommended as the most efficient ones.  相似文献   
22.
Landslide is one of the natural disasters which causes a lot of annual damage directly or indirectly in the world. Many planned areas, especially in hilly regions, are prone to different types of landslides; therefore, landslide susceptibility maps become an urgent issue, so that landslide damages and impact can be minimized. The best method for studying landslides, which has long been of interest to researchers, is hazard zonation. In this method, due to the affecting factors in landslide occurrence, study areas are classified into areas with low to very high risk. Different methods have been developed for this purpose. In this paper, the four bivariate statistical methods namely information value, density area, LNRF, and frequency ratio are used to investigate the hazard zonation of landslide in Miandarband located north of the Kermanshah Province. The density ratio (D r) and Qs values for information value, density area, frequency ratio, and LNRF methods used in this study were calculated to be 2.245312, 0.98146; 2.857816, 1.071185; 2.858085, 0.783945; and 2.418375, 1.070928, respectively. The results indicate that although there are minor differences, the frequency ratio method compared to the density area method that was used for the study of landslide zonation presents better results.  相似文献   
23.
This research has identified areas located in the northern coastline of the Persian Gulf in the south of Iran, as strategic and ecological sites, based on tourism potential assessing criteria. To this end coastal limits were identified by satellite imagery in terms of shorelines and the maximum extent of water approach into the land and taking into consideration the characteristics of the nearby coastal villages. The studied region was then compared to similar international criteria and experiences. The original criteria were then divided into three main and four sub criteria. The Kangan region was found to have a potential for tourism industry according to the mentioned criteria. Naiband Gulf with a score of 20 was ranked first followed by Asalouyeh with a score of 18 and finally Taheri and Kangan Ports with scores of 16 and 15, respectively. With a high tourism industry potential in the studied region the necessity of ecotourism quality enhancement and environmental management planning for the northern shoreline of the Persian Gulf becomes of vital importance.  相似文献   
24.
In this study, AERMOD dispersion model has been applied for predicting the values of ambient concentrations of NO2 emissions due to the stacks of fourth gas refinery located in South Pars Gas Complex in Asaluyeh, Iran. First, the values of NO2 emissions from the stacks and the amounts of ambient concentrations of NO2 in nine monitoring stations have been measured in four seasons in 2013. Then, dispersion of NO2 emissions has been predicted by using AERMOD model in the region with the domain area of 10 × 10 km2, in average times of 1 h. Finally, the simulated and observed values of ambient NO2 concentrations in the nine receptors have been compared. Comparison of 1-h concentrations of the observed and predicted results with the international ambient standard levels shows that NO2 concentrations are higher than the standard value. The results show that AERMOD model can be used effectively for predicting the amounts of pollutants’ concentrations in the study area.  相似文献   
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26.
This study presents energy efficiency measures in fans as an important energy consumption facility in the industry and common usages by identifying the sources of energy loss and applying methods to reduce those losses, which are one of the critical issues in protecting the environment and in global warming. The carbon footprint can be lowered by reducing the energy consumption of a fan over its life cycle. The main sources of energy loss in fans such as noise, vibration, lubrication, temperature of the bearings, installation type, damper and filter, especially pulley and belt system compared to electrical variable speed drive, are theoretically and experimentally discussed. The laboratory results show that the mechanical variable speed drive is one of the critical sources of energy loss in centrifugal fans. The results also show that by changing the drive with an electrical variable speed drive, the energy usage can be substantially optimized. For instance, using an electrical variable speed drive has reduced the energy loss up to 38.5?% with regard to the speed and according to the different flow rates. Moreover, based on the results derived from the equations and figures, it can be concluded that a considerable amount of energy per year, as well as the related cost can be saved and this shall be noted particularly in industrial applications.  相似文献   
27.
Crisis management is a time-critical and collaborative activity that requires rapid assessment and decision-making. This study aims to develop a framework to increase teamwork efficiency by spatio-temporal modeling of human group activities in geospatial information systems. For this purpose, time geography framework was extended with round-robin scheduling and then was integrated in geographic information system environment to manage human activities in a spatio-temporal framework. The proposed framework enjoys the graphical presentation of the tasks to be executed, as well as mathematical modeling of the complex interactions to be managed. To validate the proposed model, activities of an earthquake life-detection team in normal and suggested framework were simulated and assessed. An average improvement of 18.69 % (in time and the number of rescuers) was observed using the proposed framework. The suggested framework helps to resolve multidimensional problems in risk management.  相似文献   
28.
This study aims to assess the extent of metal accumulation by plants found in a mining area in Hamedan Province in the central west part of Iran. It also investigates to find suitable plants for phytoextraction and phytostabilization as two phytoremediation strategies. Plants with a high bioconcentration factor (BCF) and low translocation factor (TF) have the potential for phytostabilization while plants with both BCFs and TFs greater than one have the potential to be used for phytoextraction. In this study, shoots and roots of the 12 plant species and the associated soil samples were collected. The collected samples were then analyzed by measurement of total concentrations of trace elements (Pb, Zn, Mn and Fe) using atomic absorption spectrophotometer. Simultaneously, BCF and TF parameters were calculated for each element. Results showed that although samples suitable for phytoextraction of Pb, Zn, Mn and Fe and phytostabilization of Fe were not detected, Scrophularia scoparia was the most suitable for phytostabilization of Pb, Centaurea virgata, Echinophora platyloba and Scariola orientalis had the potential for phytostabilization of Zn and Centaurea virgata and Cirsium congestum were the most efficient in phytostabilization of Mn. Present study showed that native plant species growing on contaminated sites may have the potential for phytoremediation.  相似文献   
29.
Bore holes were drilled in the Senonian limestone of the Hedils-Jalta area (northern Tunisia) in order to determine their potential as an aquifer. Structural, tectonic and hydrogeologic data compilation shows the discrimination of productive and not productive zones. Differential hydraulic productivity was recognised with four distinct productive geological zones separated by a sterile corridor trending NW–SE. The structure consists of two compressional dihedrons, limited by two conjugate strike-slip faults, trending NNE–SSW and nearly E–W. The reduction of the (1) potential reservoir, (2) the low hydraulic productivity of the central band, (3) the torsion of the fold axis in eccentric arcs on both sides of the compressive relay and (4) the differential hydrogeological zonation are all related to the distribution of stress in the interference zone between conjugate strike-slip faults and to the reorientation of the stress field in their vicinity. This study constitutes a main database in establishing strategies for groundwater exploration in the similar zones.  相似文献   
30.
Uplift capacity of plate anchors has been the focus of numerous studies, because anchor plates are designed for pull‐out in normal operating conditions. However, the response of plate anchors under 6‐degrees‐of‐freedom loading caused during extreme loading conditions is poorly understood. The purpose of this study is to propose a simple yet sufficiently accurate analytical solution to investigate the behavior of plate anchor under combined in‐plane translation and torsion and to evaluate its effect on the plate uplift bearing capacity. To this end, a modified plastic limit analysis (PLA) approach is introduced and compared with limit equilibrium and simplified upper bound baseline solutions. The proposed method is verified with 3‐dimensional finite element. The variables considered in this study include plate aspect ratio, plate thickness, as well as load direction and eccentricity. Results of analytical solutions indicate the insensitivity of the “shape” of the shear‐torsion yield envelope to plate thickness. This finding facilitates the use of simplified yet reasonable yield envelope for infinitely thin plate obtained from simplified PLA approach for other plate thicknesses. The “size” of the failure envelope (controlled by pure torsional and translational capacity) could be predicted fairly accurately by PLA and limit equilibrium methods. Combination of these analytical methods offers a simple yet reasonably accurate solution to describe shear‐torsion response of anchor plate. The obtained shear‐torsion yield envelope is then fitted in the generalized 6‐degrees‐of‐freedom yield surface which describes the reducing effect of moment, torsion, and planar forces on the uplift capacity of plate.  相似文献   
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