排序方式： 共有27条查询结果，搜索用时 15 毫秒
1.
Malika Kili Bouabid El Mansouri Jamal Chao Abderrahman Ait Fora 《Comptes Rendus Geoscience》2006,338(16):1194-1202
The Rharb basin is located in northwestern Morocco. It is a part of one of the most important hydrogeological basins of Morocco, and extends over some 4000 km2. The nature of its Plio-Quaternary sedimentary fill and its structural and palaeoenvironmental contexts are reflected by great variations in aerial and temporal facies distribution. This distribution, in turn, is a direct cause of the observed complexity in the geometry of potentially water-bearing beds. In the present work, we present an image of potential new hydrogeological reservoirs and define new structures that partially explain their architecture. To cite this article: M. Kili et al., C. R. Geoscience 338 (2006). 相似文献
2.
The estimation of wave transmission across the fractured rock masses is of great importance for rock engineers to assess the stability of rock slopes in open pit mines. Presence of fault, as a major discontinuity, in the jointed rock mass can significantly impact on the peak particle velocity and transmission of blast waves, particularly where a fault contains a thick infilling with weak mechanical properties. This paper aims to study the effect of fault properties on transmission of blasting waves using the distinct element method. First, a validation study was carried out on the wave transmission across a single joint and different rock mediums through undertaking a comparative study against analytical models. Then, the transmission of blast wave across a fault with thick infilling in the Golgohar iron mine, Iran, was numerically studied, and the results were compared with the field measurements. The blast wave was numerically simulated using a hybrid finite element and finite difference code which then the outcome was used as the input for the distinct element method analysis. The measured uplift of hanging wall, as a result of wave transmission across the fault, in the numerical model agrees well with the recorded field measurement. Finally, the validated numerical model was used to study the effect of fault properties on wave transmission. It was found that the fault inclination angle is the most effective parameter on the peak particle velocity and uplift. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
3.
A. Aryanasl J. Ghodousi R. Arjmandi N. Mansouri 《International Journal of Environmental Science and Technology》2016,13(5):1269-1276
“Environmental issues” along with raising awareness of people about the value of ecological systems and the growth of environmentalism have affected businesses systems and models by introducing new concepts and models for business such as sustainable business model. European Foundation for Quality Management (EFQM) Excellence Model provides a clear path for a company to follow in order to achieve its planned results which can be called sustainable business. The purpose of this study is to explore whether the mentioned model is suitable for the businesses that are based on cleaner production and sustainable business models. The method used in this study is an explorative one based on the literature review and exploration of the adaptability of EFQM Excellence Model (2013), including its fundamental concepts and its criteria, to eight archetypes of sustainable business. The results showed that out of eight fundamental concepts of this model, four are aligned with sustainable business model and four need redefining. Moreover, it was found that environmentalism should be added to the five enablers of the model, and results criteria of it needed to be restructured and redefined. In conclusion, it was shown that despite adoptability of the fundamental concepts of EFQM Excellence Model, there were some lacking criteria for adapting them to sustainable business model. Having this in mind, a modified type of model with the new defined criteria was proposed in this study. 相似文献
4.
Geophysical data sets are growing at an ever-increasing rate, requiring computationally efficient data selection(thinning)methods to preserve essential information. Satellites, such as Wind Sat, provide large data sets for assessing the accuracy and computational efficiency of data selection techniques. A new data thinning technique, based on support vector regression(SVR), is developed and tested. To manage large on-line satellite data streams, observations from Wind Sat are formed into subsets by Voronoi tessellation and then each is thinned by SVR(TSVR). Three experiments are performed. The first confirms the viability of TSVR for a relatively small sample, comparing it to several commonly used data thinning methods(random selection, averaging and Barnes filtering), producing a 10% thinning rate(90% data reduction), low mean absolute errors(MAE) and large correlations with the original data. A second experiment, using a larger dataset, shows TSVR retrievals with MAE < 1 m s-1and correlations 0.98. TSVR was an order of magnitude faster than the commonly used thinning methods. A third experiment applies a two-stage pipeline to TSVR, to accommodate online data. The pipeline subsets reconstruct the wind field with the same accuracy as the second experiment, is an order of magnitude faster than the nonpipeline TSVR. Therefore, pipeline TSVR is two orders of magnitude faster than commonly used thinning methods that ingest the entire data set. This study demonstrates that TSVR pipeline thinning is an accurate and computationally efficient alternative to commonly used data selection techniques. 相似文献
5.
F. Atabi F. Moattar N. Mansouri A. A. Alesheikh S. A. H. Mirzahosseini 《International Journal of Environmental Science and Technology》2013,10(2):283-294
This study investigates the variations of benzene concentration levels in district 1, situated in the north part of Tehran, capital of Iran. Thirty-three stations in five categories, namely roadsides, busy roads, residential areas, traffic intersections, and the vicinity of gas stations, were monitored during the rush hours in the afternoon once a week over a period of 1 year. Accordingly, benzene concentration levels were measured and predicted by inverse distance weight model. The recorded benzene concentration levels were then compared with those reported in other parts of the world. According to the results, the annual concentration levels of benzene was 13.85 ppb for roads with heavy traffic flow, 14.98 ppb for traffic intersections, 29.01 ppb for the vicinity of the gas stations, 3.26 ppb for residential areas, and 9.97 ppb for roadsides. The concentration of benzene in the vicinity of the gas station sampling point was higher than in the other stations, and at all locations was found to be so much more than the standard concentration levels (1.56 ppb) prescribed by Environmental Protection Agency for the ambient air quality. The results of the study revealed that the benzene concentration levels in Tehran are distinctly more than its standard level. This is mainly attributed to the poor quality of fuel and lack of a standard system for controlling petrol vapors in the gas stations. 相似文献
6.
M. Abbaspour Ph.D. M. J. Jafari N. Mansouri F. Moattar N. Nouri M. Allahyari 《International Journal of Environmental Science and Technology》2008,5(3):297-304
Underground railway systems, can generate heat from their operations to raise the temperatures of carriages and the station substantially. This may lead to passenger discomfort and complain especially in warm weather conditions that prevail in Tehran if underground environment is not cooled. Transportation air conditioning Committee of American Society of Heating, Refrigerating and air-conditioning Engineers proposed the Relative Warmth Index for thermal comfort design and investigation in subway environment. In this research, thermal comfort at Tehran metro stations and carriages of lines 1 and 2 has been studied using this index. The measurements were taken during two periods of September 2006 and July 2007 at different zones of stations. For this purpose, temperature, relative humidity and air velocity were measured at different times. The status of the air-conditioning systems together with passenger traffic was also recorded. A total number of 231 measurements including 114 and 117 measurements were carried out in September 2006 and in July 2007 respectively. The measurements in September 2006 did not exceed the thermal limit. However, it did exceed in July 2007. In comparison, with thermal comfort level of metros all over the world, Tehran Metro stands in an acceptable condition, while the maximum capacity of air-conditioning systems was not used, if so the thermal comfort condition would be better. 相似文献
7.
Iran is one of the most seismically active areas of the world and frequently suffers from destructive earthquakes. Rare studies on anthropogenic-induced seismicity in Iran may be related to less attention to triggered events and more concern to natural origin of earthquakes. Hence, the present study as a frontier research aims to investigate the mining-induced earthquakes in Iran. For this purpose, distribution of ~?76,000 seismic events was investigated between the years 2006 and 2013. This study considered a correlation test to investigate the possible mining triggering of the seismic events based on a network of 194 geographical pixels (1°?×?1°) in ArcGIS. Results conveniently confirmed a positive meaningful relation between all earthquake events with magnitudes M?>?0.5 and mining activities in Iran (R?=?0.42). Detailed results confirmed that the most of earthquake swarms (at least ~?60%) had mining-induced origin, which were spatially located in same pixels of metallic mineral mining sites. The correlation test between earthquake swarms and mining activities indicated positive and meaningful relationships in four regions of Alborz, Kopet Dag, Kerman, and Zagros, respectively (R?=?0.61, 0.54, 0.51, and 0.50). Hence, aforementioned seismic regions exposed sensitive seismic responses toward mining triggering effects in Iran. 相似文献
8.
Motamed Hooman Ghafory-Ashtiany Mohsen Amini-Hosseini Kambod Mansouri Babak Khazai Bijan 《Natural Hazards》2020,101(1):87-102
Natural Hazards - Analysis of the run-out of landslides is essential and vital for disaster mitigation. However, accurate run-out analysis is difficult because of the uncertainty of earthquake... 相似文献
9.
Yemen is a semi-arid country with very limited water resources. Sana’a Basin is located in the central part of Yemen and is the major source of water for drinking and irrigation. High abstraction rates in Sana’a Basin rising from 21.1 million (M) m3 in 1972 to 227.7?Mm3 in 2006, have led to a major decline in water levels and deterioration in groundwater quality. Effective management of groundwater resources in Sana’a Basin can be aided by modelling. FEFLOW was used to build a groundwater flow model for the basin and the model was calibrated under transient conditions for the period 1972–2006. The water balance for transient conditions of the Sana’a Basin in 2006 indicated that the total annual inflow was 116.9?Mm3, and the total annual outflow was 245.8?Mm3. Three scenarios for potential groundwater extraction for the period 2006–2020 are presented. The first represents the present status based on the 2006 extraction rates without introducing any management measures. The second is based on maximum domestic, agricultural and industrial consumption of water resources. The third simulates the effect of water-resource augmentation, i.e. the increase of groundwater recharge, and maximizes sustainability by reducing water consumption. Identified areas of the basin require prompt management action. 相似文献
10.
Kinetic modeling of carbon and nutrients removal in an integrated rotating biological contactor-activated sludge system 总被引：3，自引：1，他引：2
A. Akhbari A. A. L. Zinatizadeh P. Mohammadi Y. Mansouri M. Irandoust M. H. Isa 《International Journal of Environmental Science and Technology》2012,9(2):371-378
In this study, kinetics of biological carbon, nitrogen, and phosphorous removal from a synthetic wastewater in an integrated rotating biological contactor-activated sludge system was investigated. The experimental data obtained from varying four significant independent factors viz., hydraulic retention time, chemical oxygen demand for nitrogen to phosphorus ratio, internal recirculation from aerobic to anoxic zone and disks rotating speed were used for the process kinetic modeling. In order to obtain the bioprocess kinetic coefficients, Monod, first-order and Stover?CKincannon models were employed. As a result, Monod and Stover?CKincannon models were found to be the appropriate models to describe the bioprocess in the rotating biological contactor-activated sludge system as the determination coefficient for the first-order model obtained less than 0.79. According to the Monod model, growth yield, microbial decay rate, maximum specific biomass growth rate, and half-velocity constant coefficients were found to be 0.712?g VSS/g COD, 0.008/d, 5.54/d and 55?mg COD/L, respectively. From Stover?CKincannon model, the maximum total substrate removal rate constant and half-velocity constant were determined as 15.2, 10.98, 12.05?g/L?d and 14.78, 7.11, 6.97?mg/L for chemical oxygen demand, nitrogen and phosphorus removal, respectively. The kinetic parameters determined in this study can be used to improve the design and operation of the biological contactor-activated sludge system in full scale. 相似文献