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21.
The present work deals with the palaeoenvironment and depositional setting of the subsurface sediments from bore hole RT-4 of Tamra block from Raniganj coalfield of Damodar Basin, India. Nineteen shale samples were subjected to palynological and coal petrographical analyses. On the basis of botanical affinity between the miospores and the parent plants as well as the different plant groups, each coal plant assemblage was determined. The dominance of bisaccates such as Scheuringipollenites, Faunipollenites (=Protohaploxypinus), Striatopodocarpites and presence of monosaccates such as Densipollenites, Parasaccites reflect a peat forming community composed mainly of gymnosperms. Subordinate trilete spores derived from filicopsids (Cyclogranisporites, Horriditriletes, Brevitirletes, Callumispora, Microbaculsispora, Microfoveolatispora, Cyclobaculisporites), lycopsids (Indotriradites, Gondispoirtes and Didecitriletes) and sphenopsids (Laevigatosporites ) are less abundant occurring in variable proportions reflecting a hypautocthonous taphocenose. Presence of Botryococccus algae has been recorded. Palynofacies and petrographic analyses suggest deposition in open mires in a Limnic to limno-telmatic conditions with intermittent flooding of the site.  相似文献   
22.
In this paper, an analysis has been presented for calculating the pressure of an adjacent rectangular footing resting on reinforced sand for a given settlement. An approximate method has been suggested to compute the ultimate bearing capacity of adjacent footings resting on reinforced earth slab. The computation of normal force on the reinforcement area and estimation of interfacial friction coefficient at different layer levels are two essential steps in computation of pressure ratio. The process has been simplified by presenting suitable charts in non-dimensional form that can be directly used by practicing engineers.  相似文献   
23.
The Middle Siwalik clays at Dholkhand, Saharanpur district, U. P., in India were studied to investigate the nature of Siwalik (middle Miocene to lower Pleistocene) sedimentation in relation to the tectonism associated with the Himalayan orogenesis. The clays are reddish brown to buff in color containing montmorillonite, expandable mixed-layers, degraded chlorite, and illite. The clays were studied byX-ray diffractometry using standard techniques with copper radiation. The clay mineral distribution of the Middle Siwaliks indicates that the material was deposited under continental conditions in stream channels during periods of minimum current activity. The clays were deposited by slow sedimentation and are little affected by diagenesis. Further work in this area and elsewhere are now under progress to establish the relation of Siwalik sedimentation with the uplift of the Himalayas in the Tertiary period.  相似文献   
24.
The study explores the use of multiple criteria decision techniques in predicting spatial niche of Brown oak (also known as Kharsu oak, Quercus semecarpifolia Sm.) formation in midaltitude (2,400–3,500 meter amsl) Kumaun Himalaya. Predictive models using various climatic and topographical factors influencing Brown oak’s growth and survival were developed to define its current ecological niche. Analytical Hierarchical Process (AHP) method involving Saaty’s pair-wise comparison was performed to rank the explanatory powers of each compared variable. Variables were suitably weighted using fuzzy factor standardization scheme to reflect their relative importance in defining species niche. An optimum indicator was then chosen for deriving a site suitability map of brown oak. This study establishes the role of aspect in the current distribution of the species along with known influence of altitude. Future niches of oak has been tracked in the projected climate change scenario of +1°C and +2°C rise in temperature and 20 mm in precipitation. The results show that on predicted +1°C and +2°C increase in temperature, present habitat of brown oak distribution may be reduced by 40 per cent and 76 per cent respectively.  相似文献   
25.
A detailed geological, geomorphological and landuse/landcover study has been carried in a small watershed of Himalaya by visual interpretation of FCC prepared from band 123 of ASTER satellite imagery. On the basis of interpretation and field check, major litounits identified in the study area include Lesser Himalaya conglomerate consisting of quartzite, granite, phyllite boulder and pebble, Middle Siwalik sandstone and Upper Siwalik boulder beds and valley fill with Doon gravel of Holocene age. Geomorphologically the study area is characterized by typical Himalayan topography with rugged terrain. Various landforms identified and recognized include, Doon Fan Gravel Terrace, Doon Fan Gravel Dissected hill, Sub Recent Fan Terrace, Moderately Dissected Structural Hill, Piedmont Dissected Slope, River Terrace, Channel Bar and River channel. Supervised classification of ASTER False Colour Composite (FCC) (123) shows that the major landuse category in the study area is agriculture while major landcover class is forest covered land. The study shows the effect of geology and geomorphology on the type of landuse and landcover in an active tectonic zone of the study area.  相似文献   
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27.
In this era of rapid global change, biodiversity monitoring and improving species repository to meet requirements toward conservation is costly affairs and needs a practical solution to identify and locate species with habitats. The integrated approach of citizen science and information technologies has proven to be effective solution for geographical and taxonomical data collection with public engagement, covering local to national scale. As a first step, a mobile app is designed and developed for the IBIN (Indian Bioresource Information Network), a digitized collection of the biological resources of India that serves as a common platform to access spatial and non-spatial information on biorecources can host their data through this single and intuitive platform with full privileges and authenticity. IBIN mobile app can be seen as an efficient and rapid solution to record data on species, utilizing GPS and camera features of mobile devices. Present paper deals with the citizen science approaches, its contribution in biodiversity field, outlines the design and development of IBIN mobile app and its first case study carried out at foothills of Himalaya.  相似文献   
28.
With the advent of energy rating systems and increased energy efficiency requirements for built environment, the assessment of energy performance of new buildings and refurbishment rates of existing buildings have become an important compliance in the building design process. In order to analyse and simulate the effects of energy-efficient measures for buildings, it is essential to establish spatio-semantic information interoperability between the building design and energy modelling softwares. Data interoperability facilitates different domains to interact with the single building model. The geometrical properties of building semantics such as effective areas exposed to total incident radiation were used as indicators for assessment of seasonal solar potential of buildings. The key urban solar potential indicators were identified based on the semantic components of buildings. The CityGML instance document derived from a proposed energy application domain extension (ADE) conceptual schema could be used as common interoperable model for both the design and energy simulation systems.  相似文献   
29.
In the present paper, a method of analysis for calculating the pressure intensity corresponding to a given settlement for eccentrically and obliquely loaded square and rectangular footings resting on reinforced soil foundation has been presented. The process has been simplified by presenting non-dimensional charts for the various terms used in the analysis, which can be directly used by practicing engineers. An approximate method has been suggested to find out the ultimate bearing capacity of such footings on reinforced soil. The results have been validated with the model test results. The procedure has been made clear by giving an illustrative example.  相似文献   
30.
The case of a rigid wall with inclined back face retaining reinforced cohesive-frictional backfill subjected to uniformly distributed surcharge load has been analyzed using limit equilibrium approach. The analysis considers the stability of an element of the failure wedge, which is assumed to develop in the reinforced earth mass adjoining the back face of wall. The non-dimensional charts have been developed for computing the lateral earth pressure on wall and the height of its point of application above the base of wall. The theoretical findings have been verified by model tests on a rigid wall retaining a dry cohesive-frictional soil reinforced by geogrid strips. Experimental results are in good agreement with the theoretical predictions. A design example has been included to illustrate the design procedure.  相似文献   
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