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Muhammad?Abrar?Faiz Dong?LiuEmail author Muhammad?Uzair Muhammad Imran?Khan Faisal?Baig Tianxiao?Li Song?Cui 《Stochastic Environmental Research and Risk Assessment (SERRA)》2018,32(5):1225-1242
A slight variation in the magnitude of stream flow can have a substantial influence on the development of water resources. The Songhua River Basin (SRB) serves as a major grain commodity basin and is located in the northeastern region of China. Recent studies have identified a gradual decrease in stream flows, which presents a serious risk to water resources of the region. It is therefore necessary to assess the variation in stream flow and to predict the future of stream flows and droughts to make a comprehensive plan for agricultural irrigation. The simulation of monthly stream flows and the investigation of the influence of climate on the stream flow in the SRB were performed by utilizing the Integrated Water Evaluation and Planning (WEAP) tool coupled with observed precipitation data, as well as the Asian Precipitation-Highly-Resolved Observational Data Integration towards Evaluation of Water Resources (APHRODITE’s Water Resources) precipitation product. The Nash–Sutcliffe coefficient (NSC) was used to assess the WEAP efficiency. During the time of calibration, NSC was obtained as 0.90 and 0.67 using observed and APHRODITE precipitation data, respectively. The results indicate that WEAP can be used effectively in the SRB. The application of the model suggested a maximum decline in stream flow, reaching 24% until the end of 21st century under future climate change scenarios. The drought indices (standardized drought index and percent of normal index) demonstrated that chances of severe to extreme drought events are highest in 2059, 2060 and 2085, while in the remaining time period mild to moderate drought events may occur in the entire study area. The drought duration, severity and intensity for the period of 2011–2099 under all scenarios, [(A1B: 12, ? 1.55, ? 0.12), (A2: 12, ? 1.41, ? 0.09), (max. wetting and warming conditions: 12, ? 1.37, ? 0.11) and (min. wetting and warming conditions: 12, ? 1.69, ? 0.19)], respectively. 相似文献
63.
Faisal K. Zaidi 《Journal of the Geological Society of India》2011,77(2):160-166
Drainage basin morphometry is a quantitative way of describing the characteristics of the surface form of a drainage basin
and provides important information about the region’s topography and underlying geological structures. It plays an important
role in hydrogeological investigations for delineating zones of adequate groundwater potential and selecting sites for construction
of artificial recharge structures. 相似文献
64.
The Kohistan–Ladakh Arc in the Himalaya–Karakoram region represents a complete section of an oceanic arc where the rocks from mantle to upper crustal levels are exposed. Generally this arc was regarded as of Jurassic–Cretaceous age and was welded to Asia and India by Northern and Southern Sutures respectively. Formation of this arc, timings of its collisions with Asia and India, and position of collision boundaries have always been controversial. Most authors consider that the arc collided with Asia first during 102–75 Ma and then with India during 55–50 Ma, whereas others suggest that the arc collided with India first at or before 61 Ma, and then the India–arc block collided with Asia ca 50 Ma. Recently published models of the later group leave several geological difficulties such as an extremely rapid drifting rate of the Indian Plate (30 ± 5 cm/year) northwards between 61–50 Ma, absence of a large ophiolite sequence and accretionary wedge along the Northern Suture, obduction of ophiolites and blueschists along the Southern Suture, and the occurrence of a marine depositional environment older than 52 Ma in the Indian Plate rocks south of the Southern Suture. We present a review based on geochemical, stratigraphic, structural, and paleomagnetic data to show that collision of the arc with Asia happened first and with India later. 相似文献
65.
Saravanan Mariappan Masashi Kamon Faisal Haji Ali Takeshi Katsumi Tomoyuki Akai Toru Inui Masaki Nishimura 《Geotechnical and Geological Engineering》2011,29(5):881-898
This paper addresses the study conducted on the performance of landfill liner interface parameters. Interface shear strength
parameters for various combinations of 9 different lining materials were studied and presented in this paper. This comprehensive
testing program covers the interfaces between: (1) soil and compacted clay liner (CCL), (2) geomembrane (HDPEs or PVC) and
soil, (3) geosynthetic clay liner (GCL)/CCL and soil, (4) geomembrane and geotextile, (5) geotextile and soil, (6) geotextile
and GCL/CCL, and (7) geomembrane and GCL/CCL. The experiments were conducted for both at dry or optimum moisture condition
and at saturated or wet condition. The interface performance under both conditions were compared to access the material performances.
Tabulated summaries of interface test data under dry or optimum moisture condition (OMO) and saturated or wet condition are
presented in the paper. 相似文献
66.
Ali Zulfiqar Hussain Ijaz Faisal Muhammad Grzegorczyk Marco Andreas Almanjahie Ibrahim M. Nazeer Amna Ahmad Ishfaq 《Theoretical and Applied Climatology》2020,140(1):25-36
Theoretical and Applied Climatology - Drought is a complex natural hazard that has been recurrently occurred in many regions across the globe. Therefore, precise drought characterization and its... 相似文献
67.
Major accidents are low-frequency, high-consequence accidents which are not well supported by conventional statistical methods due to the scarcity of directly relevant data. Modeling and decomposition techniques such as event tree have been proved as robust alternatives as they facilitate incorporation of partially relevant near accident data–accident precursor data—in probability estimation and risk analysis of major accidents. In this study, we developed a methodology based on event tree and hierarchical Bayesian analysis to establish informative distributions for offshore blowouts using data of near accidents, such as kicks, leaks, and failure of blowout preventers collected from a variety of offshore drilling rigs. These informative distributions can be used as predictive tools to estimate relevant failure probabilities in the future. Further, having a set of near accident data of a drilling rig of interest, the informative distributions can be updated to render case-specific posterior distributions which are of great importance in quantitative risk analysis. To cope with uncertainties, we implemented the methodology in a Markov Chain Monte Carlo framework and applied it to risk assessment of offshore blowouts in the Gulf of Mexico. 相似文献
68.
Radar estimates of rainfall are being increasingly applied to flood forecasting applications. Errors are inherent both in the process of estimating rainfall from radar and in the modelling of the rainfall–runoff transformation. The study aims at building a framework for the assessment of uncertainty that is consistent with the limitations of the model and data available and that allows a direct quantitative comparison between model predictions obtained by using radar and raingauge rainfall inputs. The study uses radar data from a mountainous region in northern Italy where complex topography amplifies radar errors due to radar beam occlusion and variability of precipitation with height. These errors, together with other error sources, are adjusted by applying a radar rainfall estimation algorithm. Radar rainfall estimates, adjusted and not, are used as an input to TOPMODEL for flood simulation over the Posina catchment (116 km2). Hydrological model parameter uncertainty is explicitly accounted for by use of the GLUE (Generalized Likelihood Uncertainty Estimation). Statistics are proposed to evaluate both the wideness of the uncertainty limits and the percentage of observations which fall within the uncertainty bounds. Results show the critical importance of proper adjustment of radar estimates and the use of radar estimates as close to ground as possible. Uncertainties affecting runoff predictions from adjusted radar data are close to those obtained by using a dense raingauge network, at least for the lowest radar observations available. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
69.
Abdolhossein Khalilnejad Faisal Hj. Ali Normaniza Osman 《Geotechnical and Geological Engineering》2012,30(2):277-288
Land sliding is a geotechnical event that includes a wide range of ground movements such as rockfalls, deep failure of slopes
and shallow debris flows, and it can cause various problems in varied civil fields such as roads and dams. Since most conventional
methods are neither inexpensive nor applicable everywhere, attention has nowadays been drawn to soil bioengineering using
vegetation as the environment-friendly method for slope stabilization. Soil bioengineering or using vegetation in civil engineering
design is mostly applicable to shallow slope stabilization projects characterized by unstable slopes with surface movement.
Vegetation has both a silent effect on soil improvement to predict the landslide and a mechanical role to increase shear and
pulling-out stress on the soil. During the last decade, many researches have been carried out to clarify the effect of vegetation
on slope stability, but many questions still remain to be answered. 相似文献
70.
Faisal I. Shalabi Husam A. Al-Qablan Omar H. Al-Hattamleh 《Geotechnical and Geological Engineering》2009,27(2):237-248
Lining contact pressure and ground deformation of Raghadan transportation tunnel (Amman, Jordan) were investigated. The tunnel
is 1.1 km in length and 13.5 m in diameter. This study was intended to integrate useful relations among the widely used rock
classification system (RMR: rock mass rating), Hoek–Brown classification, and lining-ground interaction. The materials encountered
along the tunnel alignment were limestone, dolomatic limestone, marly limestone, dolomite, and sillicified limestone. The
ground conditions along the tunnel alignment including bedding planes, joint sets and joint conditions, rock quality, water
flow, and rock strength were evaluated based on the drilled boreholes and rock exposures. Elasto-plastic finite element analyses
were conducted to study the effect of rock mass conditions and tunnel face advance on the behavior of lining-ground interaction.
The results of the analyses showed that lining contact pressure decreases linearly with the increase in RMR value. Also the
results showed that tunnel lining contact pressure and crown inward displacement decreases with the increase in the unsupported
distance (distance between tunnel face and the end of the erected lining). Ground displacement above the tunnel crown was
found to be increases in an increasing rate with the decrease in the depth above the crown. This displacement was also found
to be affected by the RMR value and the unsupported distance. 相似文献