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361.
Navid Attary John W. van de Lindt Hussam Mahmoud Steve Smith Christopher M. Navarro Yong Wook Kim Jong Sung Lee 《Natural Hazards》2018,93(3):1295-1316
Resiliency of communities prone to natural hazards can be enhanced through the use of risk-informed decision-making tools. These tools can provide community decision makers key information, thereby providing them the ability to consider an array of mitigation and/or recovery strategies. The Center for Risk-Based Community Resilience Planning, headquartered at Colorado State University in Fort Collins, Colorado, developed an Interdependent Networked Community Resilience (IN-CORE) computational environment. The purpose of developing this computational environment is to build a decision-support system, for professional risk planners and emergency responders, but even more focused on allowing researchers to explore community resilience science. The eventual goal was being to integrate a broad range of scientific, engineering and observational data to produce a detailed assessment of the potential impact of natural and man-made hazards for risk mitigation, planning and recovery purposes. The developing computational environment will be capable of simulating the effects from different natural hazards on the physical and socioeconomic sectors of a community, accounting for interdependencies between the sectors. However, in order to validate this computational tool, hindcasting of a real event was deemed necessary. Therefore, in this study, the community of Joplin, Missouri in the USA, which was hit by an EF-5 tornado on May 22, 2011, is modeled in the IN-CORE v1.0 computational environment. An explanation of the algorithm used within IN-CORE is also provided. This tornado was the costliest and deadliest single tornado in the USA in the last half century. Using IN-CORE, by uploading a detailed topological dataset of the community and the estimated tornado path combined with recently developed physics-based tornado fragilities, the damage caused by the tornado to all buildings in the city of Joplin was estimated. The results were compared with the damage reported from field studies following the event. This damage assessment was done using three hypothetical idealized tornado scenarios, and results show very good correlation with observed damage which will provide useful information to decision makers for community resilience planning. 相似文献
362.
Input parameters, such as rock mass strength parameters and deformation modulus, considered in the design of underground openings involve some uncertainty. The current uncertainty in these parameters is due to the inherent variability of these parameters. To quantify these parameters and design underground openings, the statistical methods must be utilized. In this research, a statistical method was used to define the GSI of rock mass (Geological Strength Index), block volume (Vb), and joint conditions (Jc). Using the GSI distribution function obtained from field data and intact rock strength characteristics, the statistical distribution functions of rock mass parameters were defined using the Monte Carlo method. The statistical analysis of the stability in Azad-pumped storage powerhouse cavern was carried out through the point estimate method. The appropriate support system was suggested according to the support pressure and the plastic zone around the cavern. This study showed the application of the statistical method, by combining the uncertainties of the intact rock strength and discontinuity parameters, in the assessment of the strength and deformability of rock masses and the support selection process in comparison with the deterministic methods. 相似文献
363.
Monitoring of soil properties is a significant process and plays an important role about how it can be used sustainably. This study was performed in a local area in Sawda Mountains KSA to map out some soil properties and assess their variability within the area under different land cover. Soil sampling was carried out in four different sites using the grid sampling technique. Ten samples were collected in each location within a 10 by 10 km area; soil was sampled at 0–30-cm depth. The soil samples were air-dried, crushed, and passed through a 2-mm sieve before analyzing it for pH, EC, CaCO3, organic matter contents, and bulk density. The thematic maps of these characteristics were produced using ArcGIS 10.0 software. Finally, the land degradation was assessed using three factors: soil salinization, compaction, and edibility. The obtained results showed that the high risk of soil compaction, salinization, and erodibility occupied an area 5.6 ha (17.5%), 3.7 ha (11.54%), and 8.1 ha (25.3%), respectively, in the surface soil layer. The land degradation risk in the study area due to salinization was low to high; however, the degree of soil compaction was moderate to very high. The K-factor (soil erodibility) in the area ranged between 0.1 and 0.35 Mg h MJ?1 mm?1, and most of the study area was located in moderate to high erodibility classes. 相似文献
364.
Bayet-Goll Aram Esfahani Fariba Shirezadeh Daraei Mehdi Monaco Paolo Sharafi Mahmoud Mohammadi Amir Akbari 《International Journal of Earth Sciences》2018,107(6):2233-2263
International Journal of Earth Sciences - The Tournaisian–Visean carbonate successions of the Esfahan–Sirjan Basin (ESB) from Sanandaj–Sirjan Zone, Iran, have been used to... 相似文献
365.
The studied granitic bodies belong to the south Eastern Desert of Egypt. They extend in a NNW–SSE trend along the same strike of the Nugrus weakness zone by which they are structurally controlled. These rocks are composed of biotite and biotite-muscovite monzogranites to syenogranites. Geochemically, a higher abundance of Ba and Rb in biotite granites with a relatively low abundance in biotite-muscovite granites as well as the diversity of Th, U, Nb, Ta, Zr, and REE reflects their origin from different sources and geodynamic settings. The biotite granites are predominantly metaluminous to low peraluminous whereas the biotite-muscovite granites have a peraluminous nature. Potassium enrichment at the expense of calcium in these rocks reflects a derivation from crustal sources by partial melting in the presence of a volatile system. Radiometric investigation showed high abundances of U(up to 38 ppm) and Th(up to 26 ppm) in biotite-muscovite granites relative to biotite granites(up to 5 ppm U and 18 ppm Th). Radioactive anomalies furthermore have been recorded in parts of biotite-muscovite granites that were affected by the faults(up to 116 ppm eU and 97 ppm eTh). Consequently, biotite-muscovite granites form a potentially fertile source for uranium mineralization. 相似文献
366.
Lassaad Mejri Vincent Regard Sébastien Carretier Stéphane Brusset Mahmoud Dlala 《Comptes Rendus Geoscience》2010,342(11):864-872
The present-day seismicity in northeastern Tunisia reported from permanent networks is of low to moderate magnitude. However, earthquakes are mentioned in the literature, specially a destructive one in the antique city of Utique. Geologic, seismic, and neotectonic investigations in this area show that the Utique fold is closely related to the recent tectonic activity in this region. Data show that the Utique fold is built on an east-west fault, and we found evidence of activity of this fault in the past 20 kyr. A seismic section and balanced cross-section show that the slip rate is of the order of 0.38 mm.yr−1. Our data show definitively the Late Pleistocene–Holocene activity of the Utique Fault; and we can predict the earthquake recurrence interval which should be of ∼103–104 yr. This high seismic risk zone deserves to be taken into account during the establishment of important regional development programs and in the application of seismic building codes. 相似文献
367.
S. A. Elwakil A. Elgarayhi E. K. El-Shewy Abeer A. Mahmoud M. A. El-Attafi 《Astrophysics and Space Science》2013,343(2):661-666
Effect of nonthermality of ions on the propagation of dust-acoustic waves (DAWs) in unmagnetized plasma having electrons, singly charged ions, hot and cold dust grains have been investigated. The reductive perturbation method is employed to reduce the basic set of fluid equations to the Korteweg-de Vries (KdV) equation. Moreover, the energy of two temperatures charged dusty grains were computed. The present investigation can be of relevance to the electrostatic solitary structures observed in various space plasma environments. 相似文献
368.
Isotopic composition of rainfall and ground-water recharge in the western province of Saudi Arabia 总被引:1,自引:0,他引:1
Mahmoud S. Alyamani 《Journal of Arid Environments》2001,49(4):751
The oxygen-18 and deuterium isotopic compositions of rainfall from eight meteorological stations are discussed. The results show that the stable isotope distribution of the rainfall over the western province display a difference in isotopic ratios, which can be attributed to the altitude effect and water vapour sources, and to some extent, to rainfall amount. The changes of δ18O and δ D contents with altitude are −0·08 and −0·38‰ per 100 m respectively. Comparison of the isotopic analyses of rainfall and local ground-water and springs indicates that the monsoon derived rainfall that prevails during the autumn season plays a crucial role in alluvial aquifer recharge. Although Atlantic water vapour can arrive virtually throughout the area in winter months, its influence seems to be of minor importance to the water balance in the study area. 相似文献
369.
This paper presents a historical account of Brazilian public policy on fisheries subsidies, and a discussion of problems and limitations resulting from such policy. From the 1960s to the mid-1980s, public policies led to a great increase in fisheries catch without appropriate consideration for the long-term sustainability of the resources, resulting in declining catches over the years. The goals of current Brazilian public policy on fisheries will not help in reducing overexploitation. This is because these policies are too optimistic about the abundance of fish in Brazil's EEZ, and are not accompanied by a fisheries management plan that is likely to work. 相似文献
370.
Mahmoud Kh. El-Sayed Youssef Halim Hassan M. Abdel-Kader Mohamed H. Moeness 《Marine pollution bulletin》1979,10(3):84-86
Elemental mercury is associated with industrial wastes discharged through the main effluent pipe of the Chlorine-Alkali plant at El-Max area west of Alexandria. The minimal mercury value of 0.1 ppm dry weight is assumed to be the background level for uncontaminated sediments in the area. Mercury level ranged from 8.02 to 15.5 ppm in the beach sands from the polluted area beyond the plant, and from 0.14 to 1.4 ppm in the bottom sediments off Alexandria.The Chlorine-Alkali plant is obviously the major source of mercury pollution. The contribution of land drainage, agricultural and domestic wastes is insignificant. 相似文献