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61.
V. S. N. Murty V. Ramesh Babu L. V. G. Rao Charuta V. Prabhu V. Tilvi 《Journal of Earth System Science》2000,109(2):267-277
Time-series data on upper-ocean temperature, Vessel-Mounted Acoustic Doppler Current Profiler (VM-ADCP) measured currents
and surface meteorological parameters have been obtained for the first time in the southern Bay of Bengal at 7‡N, 10‡N, and
13‡N locations along 87‡E during October–November, 1998 under BOBMEX-Pilot programme. These data have been analysed to examine
the diurnal variability of upper oceanic heat budget and to estimate the eddy diffusivity coefficient of heat in the upper
layer. Diurnal variation of near-surface temperature is typical at northern location (13‡N) with a range of 0.5‡C while the
diurnal range of temperature is enhanced to 0.8‡C at the central location (10‡N) due to intense solar radiation (1050 W/m2), clear skies and low wind speeds. At the southern location (7‡N), the diurnal variation of temperature is atypical with
the minimum temperature occurring at 2000 hrs instead of at early morning hours. In general, the diurnal curve of temperature
penetrated up to 15 to 20 m with decreasing diurnal range with depth. The VM-ADCP measured horizontal currents in the upper
ocean were predominantly easterly/northeasterly at southern location, north/northerly at central location and northwesterly
at northern location, thus describing a large-scale cyclonic gyre with the northward meridional flow along 87‡E. The magnitudes
of heat loss at the surface due to air-sea heat exchanges and in the upper 50 m layer due to vertical diffusion of heat are
highest at the southern location where intense convective activity followed by overcast skies and synoptic disturbance prevailed
in the lower atmosphere. This and the estimated higher value (0.0235 m2/s) of eddy diffusivity coefficient of heat in the upper ocean (0–50 m depth) suggest that 1-D processes controlled the upper
layer heat budget at the southern location. On the other hand, during the fair weather conditions, at the central and northern
locations, the upper layer gained heat energy, while the sea surface lost (gained) heat energy at northern (central) location.
This and lower values of eddy diffusivity coefficient of heat (0.0045 and 0.0150 m2/s) and the northward intensification of horizontal currents at these locations suggest the greater role of horizontal heat
advection over the 1-D processes in the upper ocean heat budget at these two locations. 相似文献
62.
Piyoosh Rautela Ramesh Chandra Lakhera 《International Journal of Applied Earth Observation and Geoinformation》2000,2(3-4)
The area around Sataun in the Sirmur district of Himachal Pradesh, India (falling between the rivers Giri and Tons; both tributaries of the Yamuna River) was studied for landslide vulnerability on behalf of the inhabitants. The study was made using extensive remote sensing data (satellite and airborne). It is well supported by field evidence, demographic and infrastructural details and aided by Geographic Information System (GIS) based techniques. Field observations testify that slope, aspect, geology, tectonic planes, drainage, and land use all influence landslides in the region. These parameters were taken into consideration using the statistical approach of landslide hazard zonation. Using the census data of 1991, vulnerability of the populace to the landslide hazard was accessed. As most of the infrastructure in the region is concentrated around population centres, population data alone was used for vulnerability studies. 相似文献
63.
Ramesh Chander Kapoor 《Astrophysics and Space Science》1985,117(2):363-373
A numerical study has been made of the motion of a compact object consisting of a supermassive black hole with a dense cluster of stars around through a galaxy which has recoiled from the center of the latter as a result of anisotropic emission of gravitational radiation or asymmetrical plasma emission. We find that the effect of dynamical friction on its motion through the galaxy (mass1011
M
) estimated using the impulsive approximation technique, is minimal for an object mass 109
M
and for recoil taking place at a velocity larger than that of escape. A velocity 1.1 times the escape velocity is needed for the object to escape from the galaxy, whereas for velocities of recoil less than this critical velocity, damped oscillatory motion ensures. The energy exchange of the object with the galaxy is not large enough to cause appreciable change in the internal energy of the latter. 相似文献
64.
The evaporation rates over the Arabian Sea (AS) for the summer monsoon months (June to September) of 1987 have been computed using the bulk-aerodynamic formula. The satellite derived precipitation from the INSAT-1B VHRR (Very High Resolution Radiometer) sensor operating in the wavelength 10.5–12.5 m has been used for computing the precipitation over the AS. The net water vapour flux divergence (NFD) over AS has been computed as the difference between evaporation and precipitation. The estimates being -0.02 × 1010, 2.55 × 1010, 0.70 × 1010 and 0.44 × 1010 tons/day respectively for the months June, July, August and September. The NFD over AS was found to be positively and significantly correlated with the mean monsoon rainfall along the west coast of India. 相似文献
65.
V. Ramesh Babu J. S. Sastry V. V. Gopalakrishna D. V. Rama Raju 《Journal of Earth System Science》1991,100(1):55-68
The hydrographic structure in the east central Arabian Sea during premonsoon period undergoes significant temporal change
in the thermal field of upper 100 m, wherein temperature rises by about 0–5°C on an average from May to June. The major contribution
in increasing the surface layer temperature comes from surface heat exchange processes, while the horizontal advective process
tends to remove the heat from the upper layer. The geostrophic flow patterns are similar from May to June in the major part
of the study area while in the coastal areas off Goa a southerly current sets in June in response to coastal upwelling. 相似文献
66.
Suspended and bed sediments collected from the entire region of the Krishna River and its major tributaries were analyzed for heavy metals (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and Pb) by the thin-film energy dispersive x-ray fluorescence technique. There is considerable variation in the concentration of elements towards downstream, which may be due to the variation in the subbasin geology and various degrees of human impact. Suspended particles are enriched in heavy metals throughout the basin relative to bed sediments. The heavy metals are enriched in coarse size fractions (10–90 µm) throughout the Krishna River except its tributary Bhima, where finer fractions (2 µm) dominate. Transition elements correlate very well with each other. There is a striking similarity between the bed sediments of Krishna River and the Indian average. When the annual heavy metal flux carried by the Krishna River was estimated, and viewed in relation to the other major riverine transport, the Krishna is seen to be a minor contributor of heavy metals to the Bay of Bengal. 相似文献
67.
68.
69.
Since 1980, many of the state governments in India have introduced programmes to integrate traditional medical systems (TM) into official health care institutions and services at different administrative levels. One of these schemes is at Primary Health Centres (phcs) in various districts. However, little research has been undertaken to date on relative demand and utilization, or on the extent to which TM is seen or used as a complement, alternative or supplement to biomedical services, in the same phc setting. The consumer assumes an important role in an integrated approach, where illness behaviour is understood to be a decision-making process. From the structuralist aspect also, the needs and decisions (in a given situation) as perceived by the administration are not necessarily the same as subjectively felt needs, wants, or even expressed needs of individuals. It is hoped research into the degree of usage and levels of clinical utilization of the two coexisting services will be useful in planning norms and services, estimation of recurrent expenditures and allocation of resources for effective functioning of the phcs. This paper presents the findings of a questionnaire based on a quota sample of users of phcs. eighty patients in each of the Allopathy and Siddha medicine wings were interviewed in three phcs in Tamil Nadu, a total of 480 respondents. The main issues considered in this paper are:
- Socio-economic characteristics of the users.
- Treatment patterns: differential preferences for treatment methods for various disease conditions; multiple-usage — interchangeable or concurrently for the same ailment; degree of medical pluralism; spatial patterns of movement.
- The reasons for participating in the present treatment.
- Behaviour, satisfaction, attitudes, opinions, preferences, experiences.
- Conclusions and implications of the study for research and service planning.
70.
Understanding the influences of local hydroclimatology and two large-scale oceanic-atmospheric oscillations (i.e., Atlantic Multidecadal Oscillation (AMO) and El Niño-Southern Oscillation (ENSO)) on seasonal precipitation (P) and temperature (T) relationships for a tropical region (i.e., Florida) is the focus of this study. The warm and cool phases of AMO and ENSO are initially identified using sea surface temperatures (SSTs). The associations of SSTs and regional minimum, maximum and average surface air temperatures (SATs) with precipitation are then evaluated. The seasonal variations in P-SATs and P-SSTs associations considering AMO and ENSO phases for sites in (1) two soil temperature regimes (i.e., thermic and hyperthermic); (2) urban and non-urban regions; and (3) regions with and without water bodies, are analysed using two monthly datasets. The analyses are carried out using trend tests, two association measures, nonparametric and parametric statistical hypothesis tests and kernel density estimates. Decreasing (increasing) trend in precipitation (SATs) is noted in the recent multi-decadal period (1985–2019) compared to the previous one (1950–1984) indicating a progression towards warmer and drier climatic conditions across Florida. Spatially and temporally non-uniform variations in the associations of precipitation with SATs and SSTs are noted. Strong positive (weak negative) P–T associations are noted during the wet (dry) season for both AMO phases and El Niño, while significant (positive) P–T associations are observed across southern Florida during La Niña in the dry season. The seasonal influences are predominant in governing the P–T relationship over the regions with and without water bodies; however, considerable variations between El Niño and La Niña are noted during the dry season. The climate variability influences on P–T correlations for hyperthermic and thermic soil zones are found to be insignificant (significant) during the wet (dry) season. Nonparametric clustering is performed to identify the spatial clusters exhibiting homogeneous P–T relationships considering seasonal and climate variability influences. 相似文献