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221.
222.
Resource Flows of Villages with Contrasting Lifestyles in Nanda Devi Biosphere Reserve, Central Himalaya, India 总被引:1,自引:0,他引:1
K. S. Rao S. Nautiyal R. K. Maikhuri K. G. Saxena 《山地科学学报》2005,2(4):271-293
Resource use efficiency analyses of village ecosystem are necessary for effective and efficient planning of resource utilization. This paper deals with economic and energy input-output analyses of different components of village ecosystem in representative buffer zone villages, which are practicing transhumance and settled way of lifestyles in Nanda Devi Biosphere Reserve (NDBR) of Garhwal Himalaya. While the villages practicing transhumance used various natural resources spatially segregated,the villages practicing settled way of lifestyle have to manage resources from a limited spatial area through rotation and varied extraction intensities. Forests subsidized the production activity in both type of villages and the per capita resource extractions were found to be greater in tran~humance village than settled village. Though crops provided maximum energy, in terms of economic criteria, animal husbandry played important role in both settled and transhumance villages. As villages representing both the situations showed different ways of adjustments to the conservation oriented land use changes, management authority needs to address the eco-development plans fulfilling the aspirations of all people traditionally using the resources of the Reserve to reduce the conflicts and encourage their participation in the conservation of the area. 相似文献
223.
We show that our original suggestion that gamma-ray bursts (GRB) may be flares on Magnetically Active Stellar Systems (MASS) namely flare stars, RS CVn binaries and Cataclysmic variables agrees well with the new observations of CGRO. We make a multi component fit to the log(N) - log(S) distribution and the high degree of isotropy as observed by the previous generation of satellites as well as BATSE/CGRO using the second BATSE catalogue. We then discuss individual source association and optical transient observations and show that they favor the present suggestion. We discuss the physical mechanisms and gamma-ray production processes that can occur on such systems giving the GRB their characteristics. We predict increase of anisotropy in the BATSE/CGRO observations for bright GRB. 相似文献
224.
N. Kameswara Rao 《Astrophysics and Space Science》1980,70(2):489-491
UBV observations obtained during the period 1972–73 are presented for the following five R CrB Stars: GU Sgr, SU Tau, XX Cam, DZ And, V973 Oph, and the hydrogen-poor, carbonrich stars BD +10°2179 and HD 137613. Observations of SU Tau were obtained when it was coming out of the 1972 light minimum. 相似文献
225.
IUE observations of HD 62001 do not confirm the ultraviolet variability of 0.15 mag seen from the ANS observations. These
intriguing variations in ANS observations seem to be caused by a nearby (∼ 70 arcsec away) B star getting in and out of the
field of view of the telescope, which had a jitter of 20 arcsec. There seems to be no evidence for the presence of a hot companion,
either from the energy distribution or from UV variability. However, visual light variations are present. This, coupled with
the radial velocity variations, indicates a binary nature probably of Algol type.
Based on observations obtained with IUE satellite at the Villafranca Satellite Tracking Station of the European Space Agency. 相似文献
226.
Summary. The P -wave response from a class of acoustic transition zones with exponential variation in the velocity is studied in the frequency and time domains by means of contour integration in the complex k plane and the fast Fourier transform (FFT). Interesting relationships between received pulse shapes and velocity gradients inside the transition zone are observed. It is suggested that the models could be of practical interest, e.g. in interpreting observations from explosion seismology. For one model the results from the contour integral method are compared with those from the reflectivity method of Fuchs. 相似文献
227.
228.
B. N. Ashoka G. C. Anupama T. P. Prabhu S. Giridhar K. K. Ghosh S. K. Jain A. K. Pati N. Kameswara Rao 《Journal of Astrophysics and Astronomy》1987,8(2):195-209
The evolution of the spectrum of SN1987a is traced from 1987 February 26 to March 31. Based on the low-resolution spectroscopic
data we identify the lines of H, He I, Na I, Fe II, Sc II, Ca II which are known to be present in Type II Supernovae, and
also present evidence for the existence of lines of Mg I, CaI, O I, and N I. We discuss the evolution of the Hα profile, and draw attention to its complex structure around March 30. Close
to the rest wavelength of Ha a double-peaked structure appeared in the profile with a peak-to-peak separation of ∼ 1400 km
s−1, suggestive of an expanding shell or disc of gas.
Using the available broadband photometric information, we also trace the evolution of the photosphere of SN1987a assuming
that it radiates like a supergiant. 相似文献
229.
At critical mass the triangular equilibria in the planar restricted three-body problem, when the more massive primary is an oblate spheroid with its equatorial plane coincident with the plane of motion, are in general unstable due to the presence of secular terms in the solutions of linearized equations of motion in the vicinity of these points. Existence of retrograde elliptic periodic orbits is established through suitable velocity components. The eccentricity of these orbits increases with the oblateness. 相似文献
230.
D. P. Sharma T. M. K. Marar S. Seetha K. S. Shyla K. Kasturirangan U. R. Rao J. C. Bhattacharyya M. J. Rozario 《Astrophysics and Space Science》1983,91(2):467-476
The discovery of a flare star (R.A. (1950)=6h43m6s.07, Decl.(1950)=?16°45′24″) located about 6 arc min south of Sirius is reported. During photometric observations on the night of 13 January, 1982, using the 102 cm telescope at Kavalur, India, the star was seen to brighten by 2.55 mag. inV band over a duration of about 200 s. Observations on this object for a duration of about 10.5 hr spread over seven more nights indicate the star to be variable. The results of these observations are presented. 相似文献