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991.
The Iran’s mineral sector, as a major supplier of mineral industries, plays a central role on Iran economy. Promoting the productivity in this area leads to the enhancement of the business environment. Also, it can influence the production chain and minerals value added. In this study, a comprehensive study was conducted on the major barriers/drivers factors affecting the efficiency in the mining sector. Furthermore, 16 key factors were identified using the expert views. These parameters are divided into four main categories: strengths, weaknesses, opportunities, and threats. In addition, a hierarchy model was designed in which the mentioned four efficient strategic parameters were implemented and the SWOT analysis was applied, as well as the nine macro strategies were determined. In order to prioritize these strategies, multiple steps were carried out. First, the subfactors were weighted by implementing the fuzzy multi attribute decision-making technique by combining the experts’ views and triangular fuzzy numbers. Subsequently, the strategies were prioritized by employing the group Fuzzy Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) model. The sensitive analysis of the results presents some minor changes in score of the alternatives, but no alteration was affected in the prioritized strategies. The results revealed the importance of resource allocation strategies related to the existing investments as well as supporting and facilitating the new technology in the mining sector. 相似文献
992.
The dynamic change of mining-induced stress is the main reason for large deformation of surrounding rock. To investigate the influence of mining-induced stress and deformation is important for appropriate supportive design. It also helps to raise the safety and productivity of longwall mining operations. In this paper, Weijiagou Coal Mine in Southwest China was selected as the case study. In order to research on the deformation and breakage of overlying strata, physical modeling test was carried out on the self-developed rotatable physical similar test system. By using digital image correlation (DIC) technique, the deformation of strata and development of cracks in the process of coal seam excavation were acquired, meanwhile, mining-induced stress was also monitored by pressure cell and strainmeter. According to the mechanical structure of stope, the height of the destressed zone has a significant influence on stress distribution. In order to minimize the discrepancy between the physical model test and theoretical analysis, the dimension of the plastic zone of roadway was added into the mining panel width, and the gap between the experimental and theoretical results reduced. 相似文献
993.
Hani N. Khoury 《Arabian Journal of Geosciences》2018,11(4):72
The Azraq basin (the Badia region in NE-Jordan) is rich in its industrial rocks and minerals. Most of the commodities are concentrated in one area, which is the Azraq depression (El-Qa’). The climatic changes (wet and dry) of Azraq closed lake contributed in the formation of industrial rocks and minerals in the El-Qa’. Basalt, pyroclastics, zeolites, diatomaceous earth, bentonite, palgorskite, porcelanite, saline brines, chalk, limestone, and gypsum are the potential industrial commodities. The basaltic rocks are of high alkalis content and good homogeneity and are of good potential use in constructions and cast basalt. The scoriaceous pyroclastic material proved to be of excellent properties for use as lightweight aggregates, cultivation purposes, and for the production of pozzolanic cement. Smectite-rich beds (bentonite) from Ein El Badia could be used as binder, absorbent, and additives for feeding farm animals. Palygorskite is potential for use in drilling mud, paint, pharmaceuticals, and as a filtering medium. The diatomaceous earth deposits are Moler type and could be used as filter aid and absorbent. Zeolites are efficient for agricultural purposes, animal waste, and wastewater treatment plants. Saline brine is exploited in the Azraq mudflat area for table salt. Porcelanite could be used as an absorbent of hazardous elements, abrasive, and filler. The softness and high purity of chalk enable its use as filler and in the lime production. The large limestone concretions are of high quality for use as a building stone. Gypsum (gypcrete) could be used after the removal of the undesired chert impurities. The Badia region is a highly potential area for future exploration and mining industry in a manner that achieves the required outcomes and minimizes impacts on ecosystems. 相似文献
994.
Elham Ghasemifar Manuchehr Farajzadeh Yousef Ghavidel Rahimi Abbasali Aliakbari Bidokhti 《Arabian Journal of Geosciences》2018,11(4):78
Cloud types have a substantial influence on precipitation. This paper presents a study of the monthly variations of daytime different cloud types over Iran using data collected from Moderate-resolution Imaging Spectroradiometer (MODIS) aboard Terra during 2001–2015, MODIS aboard Aqua during 2002–2015, International Satellite Cloud Climatology Project (ISCCP) H-series cloud type data during 2001–2009 and precipitation rate associated with different cloud types using Tropical Rainfall Measuring Mission (TRMM) satellite products during 2001–2009. Different cloud types were determined using MODIS cloud optical thickness and cloud top pressure data based on ISCCP algorithm. The results showed that stratocumulus and cumulus clouds have maximum occurrence frequency over marine areas especially southern seas. The maximum frequency of nimbostratus and deep convective occurrence occurred over mountainous regions particularly at the time of Aqua overpass and cirrus and cirrostratus are observed over southeast of Iran during warm months due to monsoon system. Altostratus cloud is extended in each month except January, at the time of Terra overpass while nimbostratus is seen at the time of Aqua overpass during warm months in the study area. Cumulus and altocumulus clouds have shown remarkable frequency in all months especially over marine regions during warm and fall months. The higher value of precipitation rate is related to altostratus with a rate approximately 7 mm/h at the time of Terra overpass during April. Altostratus has the maximum recorded precipitation rate except in Nov., Dec., Sep., and Jan. at the time of Terra overpass, whereas the maximum precipitation rate is linked to nimbostratus cloud activity (up to 5 mm/h) except for March, April, and Sep. at the time of Aqua overpass. Deep convective (up to 1.32 mm/h), cirrostratus (up to 1.11 mm/h), and cirrus (0.02 mm/h) are observed only in warm months. The results were compared with ISCCP cloud types so that precipitation rate classified from low to high and Spearman rank correlation was calculated. The results showed good agreement between these two cloud type data; however, there were few notable difference between them. 相似文献
995.
996.
Mohamed Sabri Arfaoui Radhouane Khouni Soufiene Dridi Fouad Zargouni 《Arabian Journal of Geosciences》2018,11(5):95
The Bou Arada-El Fahs troughs system is a particularly E-W trending collapsed structure with the manifestation of normal-to-strike-slip faults. A combined multi-source and multi-scalar structural and geophysical investigation provides important insights on the geometry and the kinematics evolution of trough systems in the Atlas of Tunisia. New data, as well as a reappraisal of available data show that the studied troughs system is established during three main successive events: the Oligocene-Miocene, the Tortonian, and the Plio-Quaternary events. The goal of this paper is to present the structural evolution of the study area, on a pre-structured substratum. The structural evolution progressed from an extensional event, manifested by the formation of grabens, passing by an episode of reactivation of faults related troughs in strike-slip motion during the Atlas compression accompanied by an en-échelon folding in foot wall and hanging wall. These results acquired and presented in the following order: We will initially present the geological context by integrating and correlating the lithostratigraphic data. We continue by examining the geometry and kinematics of structure-related troughs via the detailed geological mapping, the interpretation of available 2D seismic data, and the interpretation of processed fault slip data. This integrated geological and geophysical study allows a better understanding of the BETS, and makes it possible to propose a new geometrical and kinetic model of the establishment of trough structure in the Tunisian Atlas. 相似文献
997.
Hemant Kumar Singh Aswathi Thankappan Poonam Mohite Satish Kumar Sinha Dornadula Chandrasekharam Trupti Chandrasekhar 《Arabian Journal of Geosciences》2018,11(6):137
Tulsishyam thermal springs are located in the Saurashtra region of Gujarat, India with discharge temperatures varying from 39 to 42 °C. The pH of these thermal springs varies from 7.1 to 7.4, indicating neutral character. Though these thermal springs propagate through the near surface layer of Deccan basalt, detailed geochemical analysis of the thermal waters using Piper diagram suggests that the water is interacting with the granitic basement rock. Silica and cation geothermometry estimates have reservoir temperature in the range of 138 to 207 °C categorizing it into a low to moderate enthalpy geothermal system. Furthermore, the area has high heat flow values of 53–90 mW/m2 because of shallow Moho depth. The prevailing conditions suggest that the geothermal energy can potentially be exploited through an enhanced geothermal system (EGS). The study also indicates different mineral phases that may precipitate out of water during exploitation of geothermal energy and it should be taken into account while designing an EGS for the area. 相似文献
998.
Amartanshu Srivastava Suresh Pandian Elumalai Elluru Venkata Ramana Raju 《Arabian Journal of Geosciences》2018,11(6):120
The objective of the present study was to delineate temporal and spatial changes in the coal fire and land use/cover within Bastacolla area of Jharia coal field. Studying this variation helped to decipher interconnection among the dynamics of the coal fire and concomitant changes in land use/cover. The detection of coal fires during a span of 14 years along with transitioning land use/cover was cost-effective and enabled planning for management of coal resources and environment. Landsat series of satellite data of 2002, 2009, 2013, and 2016 were processed for generating land surface temperature profiles vis-a-vis classified land use/cover of the study area. A single cut-off temperature was derived for mapping of coal fires using land surface temperature profile from 2002 to 2016. The satellite images were classified using support vector machines, and for depicting land use/cover change, post-classification change detection was done. Classification accuracy obtained was excellent with kappa coefficient ranging from 0.897 for classified image of 2002 to 0.799 for classified image of 2016. Results revealed that coal fires had shifted to the central west part of the area. Furthermore, pockets of coal fire from northern and eastern part of the study area have diminished. OB dumps and coal quarry/coal dump may be attributed towards the spatial change in coal fire while; OB dumps showed connotation with the highest temperature zones. Ground verifications for temperature profiles and coal fires were carried out using thermal camera which enunciated good agreement with results. 相似文献
999.
The main purpose of this paper is to describe ways to improve the microstructure of expansive soil by adding nanomaterials. Mechanical tests were done to explore the changes in shear strength and compression index of expansive soil that was modified by adding different amounts of two kinds of nanomaterials (nano-alumina and nano-silica). The test results show that adding 1.2% nano-alumina and about 2% nano-silica to expansive soil provides the optimal compression index. The test results show that adding 1.2% nano-alumina and about 1.5% nano-silica to expansive soil provides the optimal unconfined compression stress. Scanning electron microscopy of the microstructure of expansive soil modified by nanomaterials provided a deeper understanding of the effects of nanomaterials on improving expansive soil. 相似文献
1000.
Spatial and temporal variability of rainfall: case of Bizerte-Ichkeul Basin (Northern Tunisia) 总被引:1,自引:0,他引:1
This study examines spatial and temporal variability of rainfall in Bizerte-Ichkeul Watershed. The basin, located in the extreme north of Tunisia, covers an area of 3084 km2. Thirteen rainfall stations, with continuous monthly precipitation records over the period (1970–2011), were considered in the analysis. Two methods were used. In the first, the dimensionless standardized precipitation ratio is applied to examine precipitation temporal variation. The second method is represented by continuous wavelet analysis for the precipitation spatial analysis and the identification of the origin of its variability. The study of temporal variability of annual rainfall showed severe persistent and recurrent drought episodes over the period (1977–2001). Wavelet analysis resulted in detecting the modes and origins of precipitation variability. Three energy bands were clearly identified: (1, 2–4, and 4–8 years) for the entire watershed. The visualization of the power distribution showed that the observed modes of variability are different in their power distributions from one station to another. The approach adopted allowed the identification of two groups with the same precipitation frequency and temporal variation. These groups were defined according to the difference in occurrence of the frequency band for each station. 相似文献