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- Ajay Kumar Patel
- Bhavani Kumar Yellapragada
- M. V. R. Murti
- James Jebaseelan Samuel
- Arindam Barua
- M. P. Premchand
- Prabhat Kumar Dubey
- Jayachitra
- Ambili K. Gopinath
- S. Anitha
- Renjith Keezhoth
- Anil P. Madeckal
- D. Karthikeyan
- Sheethal Antony
- J. Suresh Babu
- R. Manohara Rao
- I. Sudar
- E. S. Padmakumar
- R. H. Rizvi
- A. K. Handa
- S. Ramanan
- M. Yadav
- A. Mehdi
- R. K. Singh
- S. Londhe
- S. K. Dhyani
- J. Rizvi
- Punam
- Rameshwar Kumar
- Naved Qaisar
Journals
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
Vishnu, R.
- Dual Polarization Lidar for Remote Sensing of Aerosols and Clouds in the Atmosphere
Abstract Views :237 |
PDF Views:73
Authors
Ajay Kumar Patel
1,
Bhavani Kumar Yellapragada
1,
R. Vishnu
2,
M. V. R. Murti
1,
James Jebaseelan Samuel
3
Affiliations
1 Centre of Studies in Resources Engineering, Indian Institute of Technology-Bombay, Powai, Mumbai 400 076, IN
2 National Atmospheric Research Laboratory, Department of Space, Government of India, Gadanki 517 112, IN
3 Photonics, Nuclear and Medical Physics Division, VIT University, Vellore 632 014, IN
1 Centre of Studies in Resources Engineering, Indian Institute of Technology-Bombay, Powai, Mumbai 400 076, IN
2 National Atmospheric Research Laboratory, Department of Space, Government of India, Gadanki 517 112, IN
3 Photonics, Nuclear and Medical Physics Division, VIT University, Vellore 632 014, IN
Source
Current Science, Vol 113, No 06 (2017), Pagination: 1134-1138Abstract
We describe an indigenously developed dual polarization lidar (DPL) system for remote sensing of the range resolved properties of non-spherical nature of air borne and cloud particles. The DPL system probes the atmosphere using a linearly polarized second harmoni cNd : YAG laser. The design of receiver optics is such that it separates the collected back scattered light into parallel and perpendicular polarization components.The ratio of intensity of perpendicular to parallel signals is known as the depolarization ratio (DR), which is a gauge for non-spherical particle content in the atmosphere. The DPL employs an external irradiance standard to calibrate the depolarization measurements.Comparison of simultaneous measurements between DPL and a similar instrument validates the utility of the system for cloud and aerosol studies. The altitude profiles of DR derived from lidar signals potentially indicate the type of major particle layers in the atmosphere.Keywords
Aerosols, Clouds, Laser, Polarization Lidar, Remote Sensing.References
- Sassen, K. and Benson, S., Ice nucleation in cirrus clouds: a model study of the homogeneous and heterogeneous mode. Geophys. Res. Lett., 2005, 27, 521–524.
- Koepke, P. and Hess, M., Nonspherical particles and their influence on the scattering function of tropospheric aerosols. J. Aerosol Sci., 1986, 17(3), 254–257.
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- Liao, H. and Seinfeld, J. H., Radiative forcing by mineral dust aerosols: sensitivity to key variables. J. Geophys. Res., 1998, 103, 31637–31645.
- Boucher, O. and Anderson, T. L. A., General circulation model assessment of the sensitivity of direct climate forcing by anthropogenic sulphate aerosols to aerosol size and chemistry. J. Geophys. Res., 1995, 100, 26117–26134.
- Bhavani Kumar, Y., Lidar research activities and observations at NARL site, Gadanki, India. Proc. SPIE, 2016, 9879, 98790S.
- Collis, R. T. H., Lidar for routine meteorological observations. Bull. Am. Meteorol. Soc., 1969, 50, 688–694.
- Bhavani Kumar, Y., Portable lidar system for atmospheric boundary layer measurements. Opt. Eng., 2006, 45(7), 076201.
- Sassen, K. and Cho, B. S., Subvisual-thin cirrus lidar dataset for satellite verification and climatological research. J. Appl. Meteorol. 1992, 31, 1275–1285.
- Hunt, W. H., Winker, D. M., Vaughan, M. A., Powell, K. A., Lucker, P. L. and Weimer, C., CALIPSO Lidar description and performance assessment. J. Atmos. Ocean. Technol., 2009, 26, 1214–1228.
- Murayama, T., Okamoto, H., Kaneyasu, N., Kamataki, H. and Miura, K., Application of lidar depolarization measurement in the atmospheric boundary layer: effects of dust and sea-salt particles. J. Geophys. Res., 1999, 104(D24), 31781–31792.
- Sugimoto, N. et al., Record heavy Asian dust in Beijing in 2002: observations and model analysis of recent events. Geophys. Res. Lett., 2003, 30(12), 1640; doi: 10.1029/2002GL016349.
- Ansmann, A. et al., Long range transport of Saharan dust to northern Europe: the 11–16 October 2001 ourtbreak observed with EARLINET. J. Geophys. Res., 2003, 108(D24), 4783, doi:10.1029/2003JD003757.
- Shimizu, A. et al., Continuous observations of Asian dust and other aerosols by polarization lidar in China and Japan during ACE-Asia. J. Geophys. Res., 2004, 109, D19S17; doi:10.1029/2002JD003253.
- Sassen, K., The polarization lidar technique for cloud research: a review and current assessment. Bull. Am. Meteorol. Soc., 1991, 72, 1848–1866.
- Integrated Navigation, Guidance and Control System and Validation
Abstract Views :224 |
PDF Views:90
Authors
Arindam Barua
1,
M. P. Premchand
1,
R. Vishnu
1,
Prabhat Kumar Dubey
1,
Jayachitra
1,
Ambili K. Gopinath
1,
S. Anitha
1,
Renjith Keezhoth
1,
Anil P. Madeckal
1,
D. Karthikeyan
1,
Sheethal Antony
1,
J. Suresh Babu
1,
R. Manohara Rao
1,
I. Sudar
1,
E. S. Padmakumar
1
Affiliations
1 Vikram Sarabhai Space Centre, Indian Space Research Organization, Thiruvananthapuram 695 022, IN
1 Vikram Sarabhai Space Centre, Indian Space Research Organization, Thiruvananthapuram 695 022, IN
Source
Current Science, Vol 114, No 01 (2018), Pagination: 109-122Abstract
The navigation, guidance and control (NGC) system of Reusable Launch Vehicle – Technology Demonstrator (RLV-TD) is the most complex system ever flown in ISRO’s launches. It includes a navigation system employing traditional inertial navigation system along with global positioning system aiding and radar altimeter, ceramic servo accelerometer package, angle of attack-based control, different control systems, including secondary injection thrust vector control, reaction control system and aero control surfaces. Closed loop simulations of integrated NGC system of RLV-TD are of utmost importance to ensure mission success by assessment of system performance in nominal and off-nominal flight conditions. Validation is achieved through progressive evaluations in different levels of integrated simulation, namely autonomous simulations, software in loop simulation, on-board processor in loop simulation, hardware in loop simulation and actuator in loop simulation using Iron Bird test facility. This article discusses the overall NGC system, challenges faced during the realization of the simulation test bed, including system design to validate the new on-board elements, commissioning of Iron Bird facility and validation through various phases of simulation. The outcome of these simulations played a crucial role in bringing about improvements and helping in the evolution of the on-board system to the final configuration, ensuring the success of the mission.Keywords
Control, Guidance, Integrated Simulation, Navigation, Reusable Launch Vehicles, Validation.References
- Etkin, B., Dynamics of Atmospheric Flight, John Wiley, 1972.
- Regan, F. J., Re-entry Vehicle Dynamics, AIAA Education Series, American Institute of Aeronautics and Astronautics, 1984.
- Zipfel, P. H., Modeling and Simulation of Aerospace Vehicle Dynamics, AIAA Education Series, American Institute of Aeronautics and Astronautics, 2000.
- LaPlante, P. A., Real-time Systems Design and Analysis, John Wiley, New Delhi, 2004, 3rd edn.
- Mapping of Agroforestry Systems and Salix Species in Western Himalaya Agroclimatic Zone of India
Abstract Views :178 |
PDF Views:112
Authors
R. H. Rizvi
1,
R. Vishnu
2,
A. K. Handa
2,
S. Ramanan
2,
M. Yadav
2,
A. Mehdi
2,
R. K. Singh
3,
S. Londhe
3,
S. K. Dhyani
3,
J. Rizvi
3,
Punam
4,
Rameshwar Kumar
4,
Naved Qaisar
5
Affiliations
1 ICAR-CSSRI Regional Research Station, Lucknow 226 005, IN
2 ICAR-Central Agroforestry Research Institute, Jhansi 284 003, IN
3 World Agroforestry, South Asia Regional Programme, New Delhi 110 012, IN
4 Himachal Pradesh Krishi Vishvidyalay, Palampur 176 062, IN
5 Sher-e-Kashmir University of Agriculture and Technology, Srinagar 190 025, IN
1 ICAR-CSSRI Regional Research Station, Lucknow 226 005, IN
2 ICAR-Central Agroforestry Research Institute, Jhansi 284 003, IN
3 World Agroforestry, South Asia Regional Programme, New Delhi 110 012, IN
4 Himachal Pradesh Krishi Vishvidyalay, Palampur 176 062, IN
5 Sher-e-Kashmir University of Agriculture and Technology, Srinagar 190 025, IN
Source
Current Science, Vol 121, No 10 (2021), Pagination: 1347-1351Abstract
In the present study, agroforestry was mapped in nine districts from Western Himalayan Region. The agroforestry area in these nine selected districts was estimated to be 332127.55 ha (12.4%). Salix alba, an important agroforestry species, accounted for about 12% of total agroforestry area in three districts of Kashmir valleyKeywords
Agroclimatic Zone, Agroforestry Mapping, Object-Oriented Classification, Remote Sensing, Tree Species.References
- Bargali, S. S., Bargali, K., Singh, L., Ghosh, L. and Lakhera, M. L., Acacia nilotica based traditional agroforestry system: effect on paddy crop and management. Curr. Sci., 2009, 96, 581–587.
- Parihaar, R. S., Bargali, K. and Bargali, S. S., Status of an indigenous agroforestry system: a case study in Kumaun Himalaya. Indian J. Agric. Sci., 2015, 85, 442–447.
- Unruh, J. D. and Lefebvre, P. A., A spatial database for estimating areas for agroforestry in Sub-Saharan Africa: aggregation and use of agroforestry case studies. Agrofor. Syst., 1995, 32, 81–96.
- Pathak, P. S., Pateria, H. M. and Solanki, K. R., Agroforestry systems in India: a diagnosis and design approach. National Research Centre for Agroforestry (ICAR), New Delhi, 2000.
- Dhyani, S. K., Handa, A. K. and Uma, Area under agroforestry in India: an assessment for present status and future perspective. Indian J. Agrofor., 2013, 315(1), 1–11.
- GoI, Report of the Task Force on Greening India for Livelihood Security and Sustainable Development, Planning Commission, Government of India, 2001, p. 231.
- Zomer, R. J., Trabucco, A., Coe, R., Place, F., van Noordwijk, M. and Xu, J. C., Trees on farms: an update and reanalysis of agroforestry’s global extent and socio-ecological characteristics. Working Paper 179. World Agroforestry Centre (ICRAF) Southeast Asia Regional Programme, Bogor, Indonesia, 2014; doi:10.5716/ WP14064.pdf
- De Mers, M. N., Fundamental of Geographic Information Systems, Wiley, New York, USA, 1997, p. 486.
- Rizvi, R. H., Dhyani, S. K., Newaj, R., Saxena, A. and Karmakar, P. S., Mapping extent of agroforestry area through remote sensing: issues, estimates and methodology. Indian J. Agrofor., 2013, 15(2), 26–30.
- Rizvi, R. H., Ram Newaj, A. K., Handa, K. B., Sridhar and Anil Kumar, Agroforestry mapping in India through geospatial technologies: present status and way forward. Technical Bulletin-1/2019, ICAR-Central Agroforestry Research Institute, Jhansi, 2019, pp. 1–35.
- Rizvi, R. H., Sridhar, K. B., Handa, A. K., Singh, R. K., Dhyani, S. K., Rizvi, J. and Dongre, G., Spatial analysis of area and carbon stocks under Populus deltoides based agroforestry systems in Punjab and Haryana states of Indo-Gangetic plains. Agrofor. Syst., 2020, 94(6), 2185–2197.
- Rizvi, R. H., Newaj, R., Srivastava, S. and Yadav, M., Mapping trees on farmlands using OBIA method and high resolution satellite data: a case study of Koraput district, Odisha. In ISPRSGEOGLAMISRS International Workshop on Earth Observations for Agricultural Monitoring, IARI, New Delhi, 18–20 February 2019.
- Barrile, V. and Bilotta, G., An application of remote sensing: objectoriented analysis of satellite data. Int. Arch. Photogramm. Remote Sensing Spat. Inf. Sci., 2008, XXXVII, 107–113.
- Shah, M., Masoodi, T. H., Khan, P. A., Wani, J. A. and Mir, S. A., Vegetation analysis and carbon sequestration potential of Salix alba plantations under temperate conditions of Kashmir, India. Indian For., 2015, 141(7), 755–761.
- Rizvi, R. H., Sridhar, K. B., Handa, A. K., Chaturvedi, O. P. and Singh, M., Spectral analysis of Hyperion hyperspectral data for identification of mango (Mangifera indica) species on farmlands. Indian J. Agrofor., 2017, 19(2), 61–64.
- Blaschke, T., Lang, S. and Hay, G. J. (eds), Object Based Image Analysis, Springer, Berlin, Germany, 2008, p. 817.