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Reddy, Venkata
- Qualitative Analysis of Oral Rehydration Solution Used in Urban and Rural Areas of Tirupati
Abstract Views :181 |
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Authors
Affiliations
1 Food Science and Nutrition Department, Sri Padmavathi Manila Vishwa Vidyalaya, Tirupati -517 502, IN
1 Food Science and Nutrition Department, Sri Padmavathi Manila Vishwa Vidyalaya, Tirupati -517 502, IN
Source
The Indian Journal of Nutrition and Dietetics, Vol 40, No 2 (2003), Pagination: 59-62Abstract
Diarrhoea remains a leading world wide cause of morbidity and mortality. In the developing countries 1.5 billion episodes of diarrhoea occurs per year in children under 5 years of age and approximately 40 lakhs of these result in death. It is well known that some enteropathogenic micro-organisms are capable of inducing functional and morphological alterations in the small bowel, contributing to intestinal malabsorption of nutrients.
- L- and S-band Polarimetric Synthetic Aperture Radar on Chandrayaan-2 Mission
Abstract Views :262 |
PDF Views:99
Authors
Deepak Putrevu
1,
Sanjay Trivedi
1,
Anup Das
1,
Dharmendra Pandey
1,
Priyanka Mehrotra
1,
S. K. Garg
1,
Venkata Reddy
1,
Shalini Gangele
1,
Himanshu Patel
1,
Devendra Sharma
1,
R. Sijwali
1,
Nikhil Pandya
1,
Amit Shukla
1,
Gaurav Seth
1,
V. M. Ramanujam
1,
Raj Kumar
1
Affiliations
1 Space Applications Centre, Ahmedabad 380 015, IN
1 Space Applications Centre, Ahmedabad 380 015, IN
Source
Current Science, Vol 118, No 2 (2020), Pagination: 226-233Abstract
Dual-frequency Synthetic Aperture Radar (SAR) operating in L- and S-band frequencies is one of the primary payloads of the Chandrayaan-2 orbiter. This payload with the capability of imaging in dual frequency (L-band: 24 cm wavelength and S-band: 12 cm wavelength) with full polarimetric mode aims for unambiguous detection, characterization and quantitative estimation of water-ice in permanently shadowed regions over the lunar poles. The payload will address the ambiguities in interpreting high values of circular polarization ratio associated with water-ice observed during previous missions to the Moon through imaging in dual-frequency fully polarimetric SAR mode. Various improved system features such as wide range of resolutions and incidence angles, synchronized Land S-band operations, radiometer mode, are built into the instrument to meet the required science objectives, adhering to stringent mission requirements of low mass, power and data rates. Major scientific objectives of dual-frequency polarimetric SAR payload are: unambiguous detection and quantitative estimation of lunar polar water-ice; estimation of lunar regolith dielectric constant and surface roughness; mapping of lunar geological/morphological features and polar crater floors at high-resolution, and regional- scale mapping of regolith thickness and distribution.Keywords
Circular Polarization Ratio, Dual Frequency, Lunar Polar Water-ice, Synthetic Aperture Radar.Full Text
References
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- Putrevu, D., Das, A., Vachhani, J. G., Trivedi, S. and Misra, T., Chandrayaan-2 Dual-frequency SAR: further investigation into lunar water and regolith. Adv. Space Res., 2016, 57, 627–646.
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