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61.
Masahiro Sugiyama Osamu Akashi Kenichi Wada Amit Kanudia Jun Li John Weyant 《Climatic change》2014,123(3-4):397-411
Energy efficiency is one of the main options for mitigating climate change. An accurate representation of various mechanisms of energy efficiency is vital for the assessment of its realistic potential. Results of a questionnaire show that the EMF27 models collectively represent known channels of energy efficiency reasonably well, addressing issues of energy efficiency barriers and rebound effects. The majority of models, including general equilibrium models, have an explicit end-use representation for the transportation sector. All participating partial equilibrium models have some capability of reflecting the actual market behavior of consumers and firms. The EMF27 results show that energy intensity declines faster under climate policy than under a baseline scenario. With a climate policy roughly consistent with a global warming of two degrees, the median annual improvement rate of energy intensity for 2010–2030 reaches 2.3 % per year [with a full model range of 1.3–2.9 %/yr], much faster than the historical rate of 1.3 % per year. The improvement rate increases further if technology is constrained. The results suggest that the target of the United Nations’ “Sustainable Energy for All” initiative is consistent with the 2-degree climate change target, as long as there are no technology constraints. The rate of energy intensity decline varies significantly across models, with larger variations at the regional and sectoral levels. Decomposition of the transportation sector down to a service level for a subset of models reveals that to achieve energy efficiency, a general equilibrium model tends to reduce service demands while partial equilibrium models favor technical substitution. 相似文献
62.
P. Mahesh Amit Bansal B. Kundu J. K. Catherine V. K. Gahalaut 《Journal of the Geological Society of India》2011,77(3):243-251
The recent 10 August 2009 Coco earthquake (Mw 7.5), the largest aftershock of the giant 2004 Sumatra Andaman earthquake, occurred
within the subducting India plate under the Burma plate. The Coco earthquake nucleated near the northwestern edge of the 2004
Sumatra-Andaman earthquake rupture under the unruptured updip segment of the plate boundary interface. The earthquake with
predominant normal motion on approximately north-south to northeast-southwest oriented plane is very similar to the 27 June
2008 Little Andaman earthquake which occurred in the South Andaman region near the trench. We provide the only available estimate
of coseismic offset due to the 2009 Coco earthquake at a survey-mode GPS site in the north Andaman, located about 60 km south
of the Coco earthquake epicentre. The not so large coseismic displacement of about 2 cm in the ESE direction is consistent
with the earthquake focal mechanism and its magnitude. We suggest that, like the 2008 Little Andaman earthquake, this earthquake
too occurred on one of the approximately north-south to northeast-southwest oriented steep planes of the obliquely subducting
90°E ridge which was reactivated in normal motion after subduction, under the favourable influence of coseismic and ongoing
postseismic deformation due to the 2004 Sumatra-Andaman earthquake. Another notable feature of this earthquake is its relatively
low aftershock productivity. We suggest that the earthquake occurred very close to the aseismic region of the Irrawaddy frontal
arc of very low seismicity where pre-existing faults are not so critically stressed and because of which the earthquake could
trigger only a few aftershocks in its immediate vicinity. 相似文献
63.
The drainage basin parameters of the groundwater-fed Chhoti Gandak River originating in the terai area of the Ganga Plain
were analyzed using topographical sheets, satellite data, and field documentation with emphasis to its implication for flood
mitigation and recharging of groundwater. The analyses indicate dominance of first order streams, gentle slope gradient, low
surface run-off, low sediment production, high infiltration rate, and low value of basin relief. The low water storage capacity,
spreading of water and concentration of peak discharge in the distal part of the river basin explain that whenever precipitation
is high in the catchment area there is flood in the distal part of the basin. The bifurcation ratio value (4.34) of this basin
describes that the drainage is carved naturally by slope and local relief and not influenced by geological structures like
lineaments and faults. 相似文献
64.
The Ganga Plain is one of the most densely populated regions of the world due to its fertile soil and availability of water. The rivers of this plain are the lifeline for millions of people of this vast alluvial plain. All rivers of this plain are characterized by narrow channel confined within wide valley. Continuously increasing pressure of population on this plain has led to the intensification of settlement even into the valley of the river. This unplanned expansion has enhanced the damage due to flooding during high-discharge period and lateral erosion during low-discharge period. Flooding and lateral erosion are identified as fluvial hazards in the Ghaghara River area. Extensive studies have been carried out on flooding, but not much attention has been paid to the phenomenon of lateral erosion. However, it has been observed that lateral erosion is an independent fluvial hazard that operates during low-discharge period. Low degree of compaction due to the presence of sandy and silty facies in the river valley deposits, mass movement, palaeocurrent pattern, and fractures initiates and enhances the lateral erosion. The present paper deals with the fluvial hazards in the Ghaghara River area. 相似文献
65.
Anil Kumar Singh Virendra Singh K. K. Singh Jayant Nath Tripathi Amit Kumar Anil Kumar Soni M. Sateesh Chinmay Khadke 《Journal of the Indian Society of Remote Sensing》2018,46(6):927-935
India Meteorological department (IMD) used INSAT-3D Metrological Satellite Imager data to drive two type rainfall estimation products viz-Hydro Estimate (HE) and INSAT Multi-Spectral Rainfall Algorithm (IMSRA) on half hourly rainfall rate and daily accumulated rainfall in millimeter (mm). Integrated Multi-Satellite Retrieval for GPM (IMERG) product is being derived by NASA and JAXA by using Global Precipitation Mission (GPM) satellites data. IMSRA and GPM (IMERG) are gridded data at 10 km spatial resolution and HE is available at pixel level (4 km at Nadir). IMD provides gridded rainfall data at 0.25° × 0.25° resolution which is based on wide coverage of 6955 actual observation. In present study, validation of INSAT-3D based Hydro Estimator (HE), INSAT Multi-Spectral Rainfall Algorithm (IMSRA) and Integrated Multi-Satellite Retrieval for GPM (IMERG) of Global Precipitation Mission (GPM) satellites are carried out with IMD gridded data set for heavy rainfall event during winter monsoon, over peninsular India (November–December 2015). In validation, Nash–Sutcliffe efficiencies (NSE), RMSE, Correlation, Skilled scores are calculated at grid level for heavy and very heavy rain categories and the values of NSE of HE (? 32.36, ? 3.12), GPM (? 68.67, ? 2.39) and IMSRA (? 0.02, 0.28) on 16th November 2015 and HE (? 13.65, ? 1.69), GPM (? 43.79, ? 2.94) and IMSRA (? 1.08, ? 1.60) on 2nd Dec 2015, for heavy and very heavy rainfall. On both days, HE is showing better rainfall estimate compare to GPM for Heavy rainfall and GPM showing better estimation for very heavy rainfall events. In all the cases IMSRA is underestimating, if daily rain fall exceeded 75 mm. 相似文献
66.
Amit Shiuly 《Journal of the Geological Society of India》2018,92(1):54-58
Peak Ground Acceleration (PGA) is a very important ground motion parameter which is used to define the degree of ground shaking during an earthquake. It is also very helpful for designing earthquake resistant structure. The PGA can be estimated by attenuation relationships using magnitude, distance, source type etc of a ground motion. In the past, several researchers have developed over 450 attenuation relationships for predicting PGA for a specific region. In the present study an attempt has been made to develop an attenuation relationship on the basis of these available previous relationships in rock site which will be applicable for any region of the world. In the present study, PGA has been expressed as a function of moment magnitude and hypo-central distance in rock site. Chi-square test have also been performed with available earthquake data in American and Indian region for verifying the accuracy of the generated attenuation relationship. Using multiple regression and Genetic Algorithm (GA) the attenuation relationship equations have also been generated. These equations will be very helpful for performing seismic hazard analysis and predicting earthquake force in any region of the world. 相似文献
67.
Pushpendra Sharma Amit Kumar Verma Anil Negi Manish Kumar Jha Pradeep Gautam 《Arabian Journal of Geosciences》2018,11(15):431
Thermoelastic deformation of rock significantly affects the stability of rock slope because thermoelastic strains may cause fracture propagation under favorable condition of failure. Rock slope stability depends on the balance between shear stress and shear resistance along the plane of weakness. Due to warming of rock slopes by heat transfer phenomena, viz. conduction and convection, considerable change in induced stresses (normal and shear) and resistance takes place which further causes instability in rock slope. In this paper, a two-dimensional finite element model has been used to simulate the stability of jointed rock slope containing crack in its upper surface. Four different cases have been simulated on the basis of infilling material (air, water, ice, water and ice) in the crack. Stability of rock slope is examined in terms of shear displacement and factor of safety for different thermal conditions of slope surface. A comparative study has been done for the four cases of infilling material in the crack. The various affecting parameters, viz. shear displacement, factor of safety, shear strength along the joint, and different surface temperature conditions, are illustrated by means of graphs. It has been found that the values of horizontal and vertical displacements are in the range of millimeters. The maximum values of horizontal and vertical displacements are 2.17 mm. Moreover, the maximum values of vertical compressive and tensile stresses are 15.4 MPa and 4.45 MPa respectively for the said four cases. According to the infilling material in the crack, the stability of the rock slope for the given geometry of slope is found in the following order: crack filled with ice < crack filled with ice and water < crack filled with water < empty crack. Validations of numerical results have been done from previous studies, and it has been found that the trends of normal stress, shear strength, and shear displacement along the joint are well matched. 相似文献
68.
Changes in sea-cliff morphologies along the 30-km-long Sharon Escarpment segment of Israel's weakly cemented Mediterranean eolianite cliff line were analyzed to gain quantitative insights into erosion characteristics associated with a high-energy winter storm (10–20 year return interval). Ground-based repeat LiDAR measurements at five sites along the cliff line captured perturbations of cliff stability by basal wave scouring during the storm, subsequent post-storm gravity-driven slope failures in the cliff face above, and return of the system to transient stability within several months. Post-storm erosion, which amounted to 70% of the total volume of cliff erosion documented, resulted in dramatic local effects of up to 8 m of cliff-top retreat. And yet, at the larger scale of the 30-km cliff line examined, erosion during the storm and the year that followed affected less than 4% of the cliff length and does not appear to be above the average cliff-length annual erosion implied by previously published decadal-scale retreat rates along this sea cliff. Our results do not support a direct association between strong storm events and elevated erosion and retreat at the cliff-line scale. 相似文献
69.
70.
Awasthi Amit Vishwakarma Kirti Pattnayak Kanhu Charan 《Theoretical and Applied Climatology》2022,147(1-2):589-604
Theoretical and Applied Climatology - The frequency and intensity of extreme events especially heat waves (HW) are growing all around the world which ultimately poses a serious threat to the health... 相似文献