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11.
Paul Eccleston Bruce Swinyard Marcel Tessenyi Giovanna Tinetti Ingo Waldmann Marc Ferlet Ranah Irshad Tanya Lim Kevin Middleton Tom Bradshaw Martin Crook Tom Hunt Berend Winter Ian Bryson Naidu Bezawada William Taylor Neil Bowles Enzo Pascale Gianluca Morgante Emanuele Pace Alberto Adriani Jean-Michel Reess Marc Ollivier Roland Ottensamer Mirek Rataj Gonzalo Ramos Zapata Jan-Rutger Schrader Avri Selig Kate Isaak Martin Linder Ludovic Puig 《Experimental Astronomy》2015,40(2-3):427-447
12.
Mohammad Amjad Sabir S. Shafiqur Rehman Muhammad Umar Amir Waseem Muhammad Farooq Fariduulah Muhammad Irshad 《Water Resources》2014,41(5):612-618
Pakistan is facing acute power dearth these days due to which people are suffering from privation and their economic condition is deflating. Expensive imported fossil fuel for thermal power generation is pressing them hard and exacerbating the situation. The total power produced in the country by all means is less by 4000 MW than the requirement of Pakistan. So this is the prime time to think about exploring aboriginal and renewable power resources. This article converses about hydro power resources of Swat, North Pakistan, one of the most promising areas in hydro power production. The area drained by the Swat River and its tributary net work is a part of Kohistan Himalayas and has a potential of more than 1000 MW that can contribute 25% to the total energy shortfall in the country and the same is 150% more than the shortfall experienced in the province of Khyber Pakhtunkhwa that hosts Swat Valley. Due to great relief difference acquired within a small stretch, the perennial Swat River and its tributaries become pertinent for power production as high head projects and also gain importance in irrigation as well. 相似文献
13.
M. A. A. Patwary P. K. Champati ray Irshad Parvaiz 《Journal of the Indian Society of Remote Sensing》2009,37(3):493-509
Structurally disturbed zones of Himalaya are among the worst landslide affected regions in the world. Although landslides
are induced/triggered either by torrential rain during monsoon or by seismic activity in the region, the inherent terrain
conditions characterize the prevailing basic conditions susceptible to landslides. Using remotely sensed data and Geographic
Information System (GIS), geological and terrain factors can be integrated for preparation of factor maps and demarcation
of areas susceptible to landslides. Moderate to high resolution data products available from Indian Remote Sensing satellites
have been utilized for deriving geological and terrain factor maps, which were integrated using knowledge driven heuristic
approach in Integrated Land and Water Information System (ILWIS) GIS. The resultant map shows division of the area into landslide
susceptibility classes ranked in terms of hazard potential in one of the structurally disturbed zones in western Himalaya
around Rishikesh. 相似文献
14.
Abolghasem Roohi Zulfigar Yasin Ahmet E. Kideys Aileen Tan Shau Hwai Ali Ganjian Khanari Elif Eker‐Develi 《Marine Ecology》2008,29(4):421-434
The invasive ctenophore Mnemiopsis leidyi (Agassiz), which was transported from the Black Sea into the Caspian Sea at the end of the 1990s, has negatively affected the ecosystem of the Caspian Sea. Zooplankton abundance, biomass and species composition were evaluated on the Iranian coast of the Caspian Sea during 2001–2006. A total of 18 merozooplankton (13 species composed of larvae of benthic animals) and holozooplankton (four Copepoda and one Cladocera) species were identified. The total number of zooplankton species found here was 50% less than in a previous investigation performed in the same region in 1996 before the introduction of Mnemiopsis leidyi into the Caspian Sea. Cladocera species seemed to be highly affected by the invasion of Mnemiopsis leidyi; only one species, Podon polyphemoides, remained in the study area, whereas 24 Cladocera species were found in the study carried out in 1996. Whereas among the Copepoda Eurytemora minor, Eurytemora grimmi, Calanipeda aquae dulcis and Acartia tonsa that were abundant before the Mnemiopsis leidyi invasion, only A. tonsa (copepodites and adults) dominated the inshore and offshore waters after the invasion. The maximum in zooplankton abundance (22,088 ± 24,840 ind·m?3) and biomass (64.1 ± 56.8 mg·m?3) were recorded in December 2001 and August 2004, respectively. The annual mean zooplankton abundance during 2001–2006 was in the range of 3361–8940 ind·m?3; this was two‐ to five‐fold less than the zooplankton abundance in 1996. During 2001–2006, the highest abundance and biomass of Mnemiopsis leidyi were observed during summer‐autumn months coincident with warm temperatures and generally when the abundance of other zooplankton organisms was low. 相似文献
15.
The dissolution rate of illite, a common clay mineral in Australian soils, was studied in saline-acidic solutions under far from equilibrium conditions. The clay fraction of Na-saturated Silver Hill illite (K1.38Na0.05)(Al2.87Mg0.46Fe3+0.39Fe2+0.28Ti0.07)[Si7.02Al0.98]O20(OH)4 was used for this study. The dissolution rates were measured using flow-through reactors at 25 ± 1 °C, solution pH range of 1.0-4.25 (H2SO4) and at two ionic strengths (0.01 and 0.25 M) maintained using NaCl solution. Illite dissolution rates were calculated from the steady state release rates of Al and Si. The dissolution stoichiometry was determined from Al/Si, K/Si, Mg/Si and Fe/Si ratios. The release rates of cations were highly incongruent during the initial stage of experiments, with a preferential release of Al and K over Si in majority of the experiments. An Al/Si ratio >1 was observed at pH 2 and 3 while a ratio close to the stoichiometric composition was observed at pH 1 and 4 at the higher ionic strength. A relatively higher K+ release rate was observed at I = 0.25 in 2-4 pH range than at I = 0.01, possibly due to ion exchange reaction between Na+ from the solution and K+ from interlayer sites of illite. The steady state release rates of K, Fe and Mg were higher than Si over the entire pH range investigated in the study. From the point of view of the dominant structural cations (Si and Al), stoichiometric dissolution of illite occurred at pH 1-4 in the higher ionic strength experiments and at pH ?3 for the lower ionic strength experiments. The experiment at pH 4.25 and at the lower ionic strength exhibited lower RAl (dissolution rate calculated from steady state Al release) than RSi (dissolution rate calculated from steady state Si release), possibly due to the adsorption of dissolved Al as the output solutions were undersaturated with respect to gibbsite. The dissolution of illite appears to proceed with the removal of interlayer K followed by the dissolution of octahedral cations (Fe, Mg and Al), the dissolution of Si is the limiting step in the illite dissolution process. A dissolution rate law showing the dependence of illite dissolution rate on proton concentration in the acid-sulfate solutions was derived from the steady state dissolution rates and can be used in predicting the impact of illite dissolution in saline acid-sulfate environments. The fractional reaction orders of 0.32 (I = 0.25) and 0.36 (I = 0.01) obtained in the study for illite dissolution are similar to the values reported for smectite. The dissolution rate of illite is mainly controlled by solution pH and no effect of ionic strength was observed on the dissolution rates. 相似文献
16.
Artificial neural network application to estimate kinematic soil pile interaction response parameters 总被引:1,自引:0,他引:1
Irshad Ahmad M. Hesham El Naggar Akhtar Naeem Khan 《Soil Dynamics and Earthquake Engineering》2007,27(9):892-905
Six artificial neural network (ANN) models are developed to predict various response parameters of kinematic soil pile interaction. These responses include (1) kinematic response factors for free and fixed head piles in homogenous soil layer to derive foundation input motion (2) normalized bending moment at fixed head of pile in homogenous soil layer (3) normalized kinematic pile moment at the interface of two soil layers of sharply different soil stiffnesses. These ANN models represent simple solutions that can be implemented in a simple calculator capable of matrix operation and bypass the site response analysis and the complex wave diffraction analysis. The data required for ANN training is generated using beam on dynamic Winkler formulation (BDWF). Fifty percent of the data is used to train the ANN models while remaining 50% is used to test the ANN models. The trained ANN models show good agreement with BDWF results. 相似文献