SS 433: results of a recent multiwavelength campaign     

Sandip K. Chakrabarti  B. G. Anandarao  S. Pal  Soumen Mondal  A. Nandi  A. Bhattacharyya  Samir Mandal  Ram Sagar  J. C. Pandey  A. Pati  S. K. Saha 《Monthly notices of the Royal Astronomical Society》2005,362(3):957-965

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Landslide Hazard Zonation using Remote Sensing and GIS: a case study of Dikrong river basin, Arunachal Pradesh, India   总被引：3，自引：0，他引：3  

Ashish Pandey  P. P. Dabral  V. M. Chowdary  N. K. Yadav 《Environmental Geology》2008,54(7):1517-1529

Landslides are among the most costly and damaging natural hazards in mountainous regions, triggered mainly under the influence of earthquakes and/or rainfall. In the present study, Landslide Hazard Zonation (LHZ) of Dikrong river basin of Arunachal Pradesh was carried out using Remote Sensing and Geographic Information System (GIS). Various thematic layers namely slope, photo-lineament buffer, thrust buffer, relative relief map, geology and land use / land cover map were generated using remote sensing data and GIS. The weighting-rating system based on the relative importance of various causative factors as derived from remotely sensed data and other thematic maps were used for the LHZ. The different classes of thematic layers were assigned the corresponding rating value as attribute information in the GIS and an “attribute map” was generated for each data layer. Each class within a thematic layer was assigned an ordinal rating from 0 to 9. Summation of these attribute maps were then multiplied by the corresponding weights to yield the Landslide Hazard Index (LHI) for each cell. Using trial and error method the weight-rating values have been re-adjusted. The LHI threshold values used were: 142, 165, 189 and 216. A LHZ map was prepared showing the five zones, namely “very low hazard”, “low hazard”, “moderate hazard”, “high hazard” and “very high hazard” by using the “slicing” operation.  相似文献   

Evaluation of EO-1 hyperion data for agricultural applications     

Anshu Miglani  S. S. Ray  R. Pandey  J. S. Parihar 《Journal of the Indian Society of Remote Sensing》2008,36(3):255-266

The present study was carried out to evaluate the satellite-based hyperspectral data available from Hyperion onboard EO-1 of NASA for agricultural applications. The study was carried out for Daurala block of Meerut district, using data of March 2005. The preliminary data analysis showed that there are 196 usable bands out of a total of 242 bands. Principal component (PC) analysis showed that about 99% of the information explained in 10 PCs. The atmospherically corrected reflectance, derived from satellite data had good agreement with the ground reflectance, observed using handheld spectroradiometer, with r² ranging from 0.85 to 0.98. A set of twenty most usable bands was selected by the criteria of maximum contribution to first five PCs and the band combinations with least inter-band correlations.  相似文献   

Empirical assessment of adaptation to climate change impacts of mountain households: development and application of an Adaptation Capability Index     

Rajiv Pandey  Nandini Maithani  Roberta Aretano  Giovanni Zurlini  Kelli M. Archie  Ajay K. Gupta  Vishnu Prasad Pandey 《山地科学学报》2016,13(8):1503-1514

The present study proposes an index to assess the potential for adaptation to climate change for households in the mountainous regions. The index provides a realistic approach to recognize social and natural factors which contribute to successful adaptation and addresses several household functions, such as social networking, livelihood strategy, adjustment strategies, resource availability and accessibility. The proposed Adaptation Capability Index (ACI) is analytically defined, mathematically formulated and field tested on mountainous households in urban and semi-urban regions of the Uttarakhand Himalaya in India. To gather data on the topic relevant to the ACI, a household scale questionnaire was developed and administered to 120 heads of households through face-to-face interviews. The results highlight higher adaptive capability of urban households and low adaptation capacity of rural households due to poor farm productivity, low accessibility and availability of resources and technological input. Future programs and policies must include and implement regulations to remedy attributive factors responsible for higher adaptation. This paper may be applicable to other mountainous regions and may provide insights for effective adaptation strategies to climate change.  相似文献   

Integrated geo-microbial and trace metal anomalies for detection of hydrocarbon microseepage in Ahmedabad block of Cambay basin,India     

M. A. Rasheed  P. L. Srinivasa Rao  Annapurna Boruah  Syed Zaheer Hasan  Bougi Mohamoud Mohamed Seddik  Disha Pandey  T. Harinarayana 《Journal of the Geological Society of India》2016,88(4):433-439

The aim of the present work is to define the geo-microbial signatures along with trace metals, and to investigate whether the geo-microbial anomalies have correlation with trace metal anomalies in Ahmedabad block of Cambay basin. The surface geochemical techniques are based on seepage of light hydrocarbon gases from the oil and gas pools to the shallow surface and can bring up near-surface oxidation reduction zones that favor the development of a diverse array of chemical and mineralogical changes. The paper reports the role of hydrocarbon microseepage in surface alterations of trace metal concentrations and hydrocarbon oxidizing bacteria and its interrelationship. For the purpose a total of 90 soil samples are collected in grid pattern of 2 x 2 km interval. The paper reports the chemical alterations associated with trace metals in soils that are related to hydrocarbon microseepages above some of the major oil and gas fields of this petroliferous region. The concentrations of V (0 to149 ppm), Cr (2 to 192 ppm), Cu (4 to 171 ppm), Se (98 to 440 ppm), Zn (56 to 1215 ppm) are obtained. It is observed that the concentrations of trace elements are tremendously increased when they are compared with their normal concentrations in soils. In this study the hydrocarbon oxidizing bacterial counts ranged between 1.0 x 10³ and 1.59 x 10⁶ cfu/g of soil sample respectively. The attempt has made for the first time, which revealed good correlation as both these anomalies are found as apical in relation. Integrated studies between trace elements and hydrocarbon oxidizing bacterial anomalies showed positive correlation with existing oil and gas wells in the study area.  相似文献   

Static massive configurations with constant local adiabatic exponents     

S. C. Pandey  M. C. Durgapal  A. K. Pande 《Astrophysics and Space Science》1991,179(1):55-73

In this work an exhaustive study of static massive configurations with a constant local adiabatic exponent (₁) has been made under various physical conditions at the centre. The static parameters of these structures have been calculated at the extreme causality condition. These structures have been used to model neutron stars and the various neutron star parameters have been calculated. The radial pulsation and rotation of these configurations have also been discussed.  相似文献   

Search for and study of photometric variability in magnetic white dwarfs     

A. F. Valeev  K. A. Antonyuk  N. V. Pit  A. S. Moskvitin  A. O. Grauzhanina  D. R. Gadelshin  S. V. Kolesnikov  E. A. Zhuzhulina  T. E. Burlakova  G. A. Galazutdinov  A. G. Gutaev  R. Ya. Zhuchkov  A. I. Ikhsanova  D. G. Zhukov  Arti Joshi  J. C. Pandey  A. F. Kholtygin  G. G. Valyavin 《Astrophysical Bulletin》2017,72(1):44-50

We report the results of photometric observations of a number of magnetic white dwarfs in order to search for photometric variability in these stars. These V-band observations revealed significant variability in the classical highly magnetized white dwarf GRW+70?8247 with a likely period from several days to several dozen days and a half-amplitude of about 0_. ^m 04. Our observations also revealed the variability of the well-known white dwarf GD229. The half amplitude of its photometric variability is equal to about 0_. ^m 005, and the likely period of this degenerate star lies in the 10–20 day interval. This variability is most likely due to the rotation of the stars considered.We also discuss the peculiarities of the photometric variability in a number of other white dwarfs. We present the updated “magnetic field–rotation period” diagram for the white dwarfs.  相似文献   

Catchment area‐based evaluation of the AMC‐dependent SCS‐CN‐based rainfall–runoff models     

S. K. Mishra  M. K. Jain  R. P. Pandey  V. P. Singh 《水文研究》2005,19(14):2701-2718

Using a large set of rainfall–runoff data from 234 watersheds in the USA, a catchment area‐based evaluation of the modified version of the Mishra and Singh (2002a) model was performed. The model is based on the Soil Conservation Service Curve Number (SCS‐CN) methodology and incorporates the antecedent moisture in computation of direct surface runoff. Comparison with the existing SCS‐CN method showed that the modified version performed better than did the existing one on the data of all seven area‐based groups of watersheds ranging from 0·01 to 310·3 km². Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

Three-dimensional velocity measurements around bridge piers in gravel bed     

Manish Pandey  P. K. Sharma  Z. Ahmad  Umesh Kumar Singh  Nilav Karna 《Marine Georesources & Geotechnology》2018,36(6):663-676

The experimental results of time average velocity components measured around circular pier models during transient scour stage using acoustic Doppler velocimeter are shown for flow pattern and turbulence characteristics. Totally, four experiments were performed under clear water scour conditions in a model of gravel bed stream. Four circular pier models of diameter 6.6, 8.4, 11.5, and 13.5?cm were used for this study. Detailed controlled measurements on velocity components, and turbulence intensities near the pier and in scour hole at 0° and 180° plane are shown. Flow structure around a pier model in the presence of a scoured region was compared with the flow structure similarly noticed around all pier model runs by utilizing the observations taken at 0° and 180° plane from flow axis. Size of the primary vortex at 0° plane with largest diameter pier model in place (R4 run) is found to be maximum and was approximately 61% larger than that for smallest diameter pier model in place (R1 run). The time-averaged velocity components of turbulence intensities plots at 0° and 180° planes are also presented around each pier.  相似文献   

What will anisotropies in the clustering pattern in redshifted 21-cm maps tell us?     

Sk. Saiyad Ali  Somnath Bharadwaj  Biswajit Pandey 《Monthly notices of the Royal Astronomical Society》2005,363(1):251-258

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