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1.
The current paper is an attempt to find a sustainable fuel strategy for passenger cars in Iran. Currently, most of Iran’s passenger cars consume gasoline, a non-renewable fossil fuel. This fuel has well-known environmental impacts, including various kinds of pollutions, as well as the threat of quick running out. These general negative characteristics of gasoline are amplified by the high consumption rate of Iran’s transportation sector, (e.g. about three times more than that of UK). The objective of this paper is firstly selecting possible alternative fuels for Iran’s transportation sector, and then proposing the percent of cars consuming these alternative fuels (along with gasoline). The best strategies are proposed based on environmental and economic considerations, and hence are more sustainable decisions comparing with the other strategies. The best strategies are found using partial order theory and Hasse diagram technique, which is a multi-criteria decision analysis (MCDA) tool.  相似文献   
2.
In this paper, a different interpretation of sustainable transportation, is introduced, in which sustainability with respect to transportation sector for the selected countries is evaluated. This interpretation characterizes “sustainable development” through “harmonic development”. It means sustainable development with special focus on transportation can be measured by the degree of conformity between environment, economy, and social aspects on one hand, and transportation on the other hand. The best indicator to perform such a measurement is elasticity. The database used for the study encompasses a series of national indicators for each country Seventy nine countries were initially selected for detailed analysis for the period of 1980–1995. The data have been extracted from centralized information sources of international agencies. The key dimensions of sustainable development i.e. social, environmental, and economic characteristics are used. Firstly, a set of sustainable transportation indicators is introduced. These indicators, which in fact are elasticities, show the relative change of non-transportation variables with respect to transportation ones. Second composite indices of three non-transportation groups with respect to four transportation modes are calculated. The composite indices are then aggregated by the Concordance Analysis Technique to achieve comprehensive transportation sustainability indices of countries, and according to these values, the countries are compared, ranked, and classified. Mathematical and statistical analyses of the database support the study quantitatively. The results for the selected indicators and countries show that from sustainable transportation point of view and based on the above-mentioned interpretation of sustainable development, United States is in the ranked first, and Sierra Leon is last among the subset of 79 countries with non-missing data. The results of the study depict an overall scheme for comparative assessment of transportation sustainability of the countries.  相似文献   
3.
Résumé La suite magmatique du Damavand — un volcan isolé dans l'Elbroz, au Nord de l'Iran-a les caractéristiques d'une association magmatique avec absarokite-shoshonitebanakite. Toutefois, la relative rareté des termes intermédiaires permet de poser le problème de l'unicité de la série.L'origine de ces laves potassiques est discutée en fonction d'une paléosubduction océanique, partie du Zagros à l'Aquitanien ou, alternativement, en fonction d'une structure naissante de la Caspienne.
Zusammenfassung Die magmatische Serie von Damavand, aus einem isolierten Vulkan in der nordiranischen Elbroz-Provinz, weist alle Eigenschaften einier Absarokit-Shoshonit-magmatischen Assoziation auf.Die Herkunft dieser Kalilaven wird in bezug auf einer ozeanischen Palaeosubduktion, die im Zagros während des Aquitains anfing, diskutiert. Die Alternative eines Zusammenhangs mit der kaspischen Struktur wird in Betracht gezogen.The Damavand magmatic series — from an isolated volcano in the Elbroz province, north of Iran — holds all characters of an absarokite-shoshonite-banakite magmatic association. However, the intermediate terms are too seldom to solve the problem of the series unity.The origin of these potassic lavas is discussed as related to either an oceanic paleosubduction which started from the Zagros at Aquitanian, or, possibly, related to the evolving Caspian structure.

du Damavand, , -. , , . .
  相似文献   
4.
An analysis of observations of airflow over Lake Ontario in a stably stratified atmosphere is presented. The relationship with theory is mentioned only in terms of what may be important to future work. Detailed air motion, potential temperature and mixing-ratio measurements are presented which show pervasive variability in the horizontal. There is no evidence of gravity waves. It is suggested that vertical mixing of the atmosphere may occur in stable conditions by a mechanism quite apart from the usual concept of the small-scale random eddy motion usually associated with surface convection. Vertical soundings are analyzed as well as two long constant-height observational runs.  相似文献   
5.
This paper presents a new optimization model to help cities in seismically active developing countries decide (1) How much to spend on pre-earthquake mitigation versus waiting until after an event and paying for reconstruction or simply not rebuilding damaged buildings? (2) Which buildings to mitigate and how? and (3) Which buildings to reconstruct and how? It extends previously developed optimization models to consider the particular issues that arise in such countries. First, the model allows for the possibility that some damaged buildings will not be reconstructed immediately and keeps track of any lost building inventory. Second, buildings can be mitigated to, or when damaged, reconstructed to, any appropriate structural type and seismic design level. Finally, the model objectives include minimizing the chance of an extremely high death toll in any one earthquake and minimizing the average annual death toll across earthquakes. The model is illustrated through a case study analysis for Tehran, Iran.  相似文献   
6.
Rock failure is observed around boreholes often with certain types of failure zones, which are called breakouts. Laboratory‐scale drilling tests in some high‐porosity quartz‐rich sandstone have shown breakouts in the form of narrow localized compacted zones in the minimum horizontal stress direction. They are called fracture‐like breakouts. Such compaction bands may affect hydrocarbon extraction by forming barriers that inhibit fluid flow and may also be a source of sand production. This paper presents the results of numerical simulations of borehole breakouts using 3D discrete element method to investigate the mechanism of the fracture‐like breakouts and to identify the role of far‐field stresses on the breakout dimensions. The numerical tool was first verified against analytical solutions. It was then utilized to investigate the failure mechanism and breakout geometry for drilled cubic rock samples of Castlegate sandstone subjected to different pre‐existing far‐field stresses. Results show that failure occurs in the zones of the highest concentration of tangential stress around the borehole. It is concluded that fracture‐like breakout develops as a result of a nondilatant failure mechanism consisting of localized grain debonding and repacking and grain crushing that lead to the formation of a compaction band in the minimum horizontal stress direction. In addition, it is found that the length of fracture‐like breakouts depends on both the mean stress and stress anisotropy. However, the width of the breakout is not significantly changed by the far‐field stresses. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
7.
This paper presents a u‐p (displacement‐pressure) semi‐Lagrangian reproducing kernel (RK) formulation to effectively analyze landslide processes. The semi‐Lagrangian RK approximation is constructed based on Lagrangian discretization points with fixed kernel supports in the current configuration. As a result, it tracks state variables at discretization points while allowing extreme deformation and material separation that is beyond the capability of Lagrangian formulations. The u‐p formulation following Biot theory is incorporated into the formulation to describe poromechanics of saturated geomaterials. In addition, a stabilized nodal integration method to ensure stability of the domain integration and kernel contact algorithms to model contact between bodies are introduced in the u‐p semi‐Lagrangian RK formulation. The proposed method is verified with several numerical examples and validated with an experimental result and the field data of an actual landslide.  相似文献   
8.
The Permian–Triassic boundary (PTB) is a world‐wide event characterized by the most extensive mass extinction in the history of life. In the Persian Gulf, the rock record of this time interval host one of the most important hydrocarbon reserves in the world: the South Pars Gas Field and its southern extension, the North Dome (or North Field). These carbonate and evaporite successions were sampled in eight wells for petrographic, geochemical and porosity–permeability studies. An important characteristic of the Dalan and Kangan formations is the centimetre‐scale lithological heterogeneities caused by facies changes and diagenetic imprints that led to the compartmentalization of these reservoirs. These Permian–Triassic (P‐T) sediments were deposited in a shallow marine homoclinal ramp. The PTB in this hydrocarbon field is represented by a reworked coarse‐grained intraclastic/bioclastic grainstone facies deposited during a marine transgression. Prolonged subaerial exposure in the P‐T transition caused hypersaline and meteoric diagenesis, including extensive cementation, dolomitization and some dissolution, influencing reservoir characteristics of bordering units. Both δ18O and δ13C values in this succession mirror worldwide excursions typical of other P‐T sections, with some variations due to diagenetic alterations. A pronounced decline in 87Sr/86Sr values, reflective of global seawater geochemistry for most of the Permian is evident in our data. Reservoir quality declines through the late Permian, as a result of facies change and diagenesis. The Late Permian is succeeded by a Triassic transgressive facies and decline in reservoir quality. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
9.
Significant potential exists for CO2 sequestration in coalbed methane reservoirs of the Black Warrior basin. Reservoir simulation is an appropriate approach to estimate both the storage capacity and methane recovery enhancement. However, prior to a reliable reservoir modeling and simulation, conducting an accurate and comprehensive reservoir characterization study is necessary. The purpose of the present study is twofold: (a) to provide a rigorous reservoir characterization study required for modeling Mary Lee coal group in the Blue Creek field of the Black Warrior basin; (b) to run fluid flow simulations to predict the performance of ECBM process applied to an under pressured zone of the Mary Lee coal group. According to the current well configuration of Blue Creek field, three applicable well patterns, namely a direct line drive, an inverted 5-spot and a normal 5-spot were separately (i.e., in three distinct cases) used for simulating ECBM. Simulations were run on an approximately 32 ha (80-acre) drainage area, and included coal matrix shrinkage/swelling effects. The injected gas was assumed to be pure CO2. Using an inverted 5-spot pattern, simulations predicted that after 7.5 years of CO2 injection, approximately 32,000 tonnes of CO2 would be sequestered per 32 ha of this zone and that methane recovery would be enhanced by 36 %. Using a normal 5-spot pattern, CO2 breakthrough would occur 2.4 years earlier, and about 40,000 tonnes CO2 would be sequestered. However, methane production would be enhanced by 33 %. Considering methane recovery enhancement, direct line drive pattern delivered poor results in comparison with two other patterns. As expected, the results also showed that CO2 injection would increase water production.  相似文献   
10.
Neotrocholina Reichel, 1956 is one of the most important benthic foraminifera in Early Cretaceous. Some of the species of this genus are indexes in biostratigraphy especially for this interval (e.g., Neotrocholina friburgensis: Late Barremian–Early Aptian; Neotrocholina aptiensis: Early Aptian). In order to conduct accurate paleontological investigations, sampling from the carbonate units of the Tirgan Formation in Kopet Dagh sedimentary basin is done. According to the occurrence level in the studied stratigraphic sections as well as biometric interpretations, two species of this genus (N. friburgensis and Neotrocholina valdensis) are pointed out.  相似文献   
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