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61.
Santosh Joshi 《Journal of Astrophysics and Astronomy》2005,26(2-3):193-201
The “Nainital-Cape Survey” program for searching photometric variability in chemically peculiar (CP) stars was initiated in
1997 at ARIES, Nainital. We present here the results obtained to date. The Am stars HD 98851, HD 102480, HD 13079 and HD 113878
were discovered to exhibit δ Scuti type variability. Photometric variability was also discovered in HD 13038, for which the
type of peculiarity and variability is not fully explained. The null results of this survey are also presented and discussed. 相似文献
62.
HR 8107, a reported new Be star, has been observed spectrophotometrically. The energy distribution curve of the star has been
compared with those of other stars of similar spectral and luminosity types and model atmospheres. On the basis of comparison
with model atmospheres an effective temperature has been assigned to the star 相似文献
63.
Bipasha Paul Shukla V. Sathiyamoorthy P. K. Pal P. C. Joshi 《Theoretical and Applied Climatology》2009,97(3-4):287-295
This paper quantifies the sensitivity of radiation budget quantities to different cloud types over the Asian monsoon region using the International Satellite Cloud Climatology Project. Multiple regression was used to estimate the radiative effects of individual cloud type. It was observed that the regression performed better when the solution was constrained with clear sky fluxes, which is evident by an improvement in R 2 statistics. The sensitivity coefficients calculated for the Asian monsoon region reveal that, while the LWCRCF and SWCRF will be most vulnerable to changes in cloud cover of deep convective clouds, NETCRF will be susceptible to changes in the nimbostratus clouds. Although the cloud radiative forcing of individual cloud types are found to be similar in sign to previous global findings, their magnitudes are found to vary. It is seen that cirrus clouds play an important role in governing the radiative behavior of this region. 相似文献
64.
B. C. Joshi M. A. McLaughlin A. G. Lyne D. A. Ludovici N. A. Pawar A. J. Faulkner D. R. Lorimer M. Kramer M. L. Davies 《Monthly notices of the Royal Astronomical Society》2009,398(2):943-948
We report on the discovery of three new pulsars in the first blind survey of the north Galactic plane (45° < l < 135°; | b | < 1°) with the Giant Meterwave Radio telescope (GMRT) at an intermediate frequency of 610 MHz. The survey covered 106 deg2 with a sensitivity of roughly 1 mJy to long-period pulsars (pulsars with period longer than 1 s). The three new pulsars have periods of 318, 933 and 1056 ms. Their timing parameters and flux densities, obtained in follow-up observations with the Lovell Telescope at Jodrell Bank and the GMRT, are presented. We also report on pulse nulling behaviour in one of the newly discovered pulsars, PSR J2208+5500. 相似文献
65.
Navin Chandra Joshi Neeraj Singh Bankoti Seema Pande Bimal Pande Kavita Pandey 《Solar physics》2009,260(2):451-463
In this article we present the results of a study of the spatial distribution and asymmetry of solar active prominences (SAP)
for the period 1996 through 2007 (solar cycle 23). For more meaningful statistical analysis we analyzed the distribution and
asymmetry of SAP in two subdivisions viz. Group1 (ADF, APR, DSF, CRN, CAP) and Group2 (AFS, ASR, BSD, BSL, DSD, SPY, LPS). The North – South (N – S) latitudinal distribution
shows that the SAP events are most prolific in the 21° to 30° slice in the Northern and Southern Hemispheres; the East – West
(E – W) longitudinal distribution study shows that the SAP events are most prolific (best observable) in the 81° to 90° slice
in the Eastern and Western Hemispheres. It was found that the SAP activity during this cycle is low compared to previous solar
cycles. The present study indicates that during the rising phase of the cycle the number of SAP events are roughly equal in
the Northern and Southern Hemispheres. However, activity in the Southern Hemisphere has been dominant since 1999. Our statistical
study shows that the N – S asymmetry is more significant then the E – W asymmetry. 相似文献
66.
Rajesh Sharma Prabha Joshi P. D. Pant 《Journal of the Geological Society of India》2009,73(2):237-248
Talc deposits of Rema area in the Kumaun Inner Lesser Himalaya are hosted within high magnesium carbonates of the Proterozoic
Deoban Formation. These deposits occur as irregular patches or pockets mainly within magnesite bodies, along with impurities
of magnesite, dolomite and clinochlore. Textures represent different phases of reactions between magnesite and silica to produce
talc. Petrography, XRD and geochemistry reveal that the talc has primarily developed at the expense of magnesite and silica,
leaving dolomite largely un-reacted. Early fluid inclusions in magnesite and dolomite associated with talc are filled with
H2O+NaCl+KCl ± MgCl2 ± CaCl2 fluids, which represent basin fluid system during diagenesis of carbonates. Their varied degree of re-equilibration was although
not pervasive but points to increased burial, and hence requires careful interpretation. H2O-CO2 fluid with XCO2 between 0.06 and 0.12 was equilibrated with talc formation. The reaction dolomite+quartz → talc was not extensive because
T-XCO2 was not favourable, and talc was developed principally after magnesite+quartz. 相似文献
67.
Sanjay Gosain Sanjiv Tiwari Jayant Joshi P. Venkatakrishnan 《Journal of Astrophysics and Astronomy》2008,29(1-2):107-111
The Solar Vector Magnetograph (SVM) at Udaipur Solar Observatory saw its first light in April 2005. The retrieval of vector fields from the imaging spectro-polarimetric observational data requires a substantial amount of computer post-processing. The GUI-based data reduction and analysis software have been developed to make the data processing pipeline user-friendly and less time-consuming. In this paper we describe these software packages. 相似文献
68.
69.
Regional scale urban built-up areas and surface urban heat islands (SUHI) are important for urban planning and policy formation. Owing to coarse spatial resolution (1000 m), it is difficult to use Moderate Resolution Imaging Spectroradiometer (MODIS) Land surface temperature (LST) products for mapping urban areas and visualization, and SUHI-related studies. To overcome this problem, the present study downscaled MODIS (1000 m resolution)-derived LST to 250 m resolution to map and visualize the urban areas and identify the basic components of SUHI over 12 districts of Punjab, India. The results are compared through visual interpretation and statistical procedure based on similarity analysis. The increased entropy value in the downscaled LST signifies higher information content. The temperature variation within the built-up and its environs is due to difference in land use and is depicted better in the downscaled LST. The SUHI intensity analysis of four cities (Ludhiana, Patiala, Moga and Vatinda) indicates that mean temperature in urban built-up core is higher (38.87 °C) as compared to suburban (35.85 °C) and rural (32.41 °C) areas. The downscaling techniques demonstrated in this paper enhance the usage of open-source wide swath MODIS LST for continuous monitoring of SUHI and urban area mapping, visualisation and analysis at regional scale. Such initiatives are useful for the scientific community and the decision-makers. 相似文献
70.
Theoretical and Applied Climatology - Coupled ocean atmosphere global climate models are increasingly being used for seasonal scale simulation of the South Asian monsoon. In these models, sea... 相似文献