Microwave radiative transfer studies of precipitation

Since the deployment of the DMSP SSM/I microwave imagers in 1987, increased utilization of passive microwave radiometry throughout the 10 - 100 GHz spectrum has occurred for measurement of atmospheric constituents and terrestrial surfaces. Our efforts have focused on observations and analysis of the microwave radiative transfer behavior of precipitating clouds. We have focused particular attention on combining both aircraft and SSM/I radiometer imagery with ground-based multiparameter radar observations. As part of this and the past NASA contract, we have developed a multi-stream, polarized radiative transfer model which incorporates scattering. The model has the capability to be initialized with cloud model output or multiparameter radar products. This model provides the necessary 'link' between the passive microwave radiometer and active microwave radar observations. This unique arrangement has allowed the brightness temperatures (TB) to be compared against quantities such as rainfall, liquid/ice water paths, and the vertical structure of the cloud. Quantification of the amounts of ice and water in precipitating clouds is required for understanding of the global energy balance

Identification and characterisation of fisheries management units

This is a discussion paper on the identification of Fisheries Management Units (FMU) in Tamil Nadu and Puducherry. The choice of fisheries management units or FMUs depends on many factors like fisheries resource configuration, structure of the fisheries, availability of information, institutional aspects and the scale or level at which one can make a significant contribution to the management goals and objectives. Six possible FMU were identified based on various groupings such as fish resources, gear based, fleet based, geographical, harvesters and subsectors, and combinations of these as the seventh FMU. The prospects of each type of FMU in the TN & P context are discussed in detail in this paper

Fisheries Management Options for Tamil Nadu & Puducherry

The specific aim or output of the work package on fisheries management is to “define a new fisheries management system” for Tamil Nadu & Puducherry (TN & PC) since it is an essential tool for achieving the long term development goal of the project. The approach was a mixture of (i) expert consultations with fishery biologists, fishery statisticians, academics, fisheries NGOs, fisheries officials, (ii) review of fisheries management with available current information, (iii) a detailed analysis of catch data species wise, district wise and sector wise (mechanised, motorised and non-motorised) and (iv) an exercise to identify potential Fisheries Management Units (FMUs) and to develop a detailed characterization of them. Based on the above, fisheries management options for TN & PC have been worked out and presented in a state level multi-stakeholder workshop and subsequently refined. This report is the outcome of this process

Marine Fish Production in Tamil Nadu & Puducherry. A Report based on a detailed analysis of Central Marine Fisheries Research Institute Data

Continuous growth in TN marine fisheries is observed in the form of introduction of new fishing vessels, fishing methods, new fishing gears and development of different infrastructure since 1950 leading to a five-fold increase in catch and three-fold increase in active fishers. There is a continuous expansion of fishing operation to deeper and distant waters. There has been a continuous discovery of new fishing grounds, new fishery resources and new fishing methods. The entire shelf area off Tamil Nadu (TN) coast is covered by TN fishing fleet and there is no scope for additional catch from the shelf area. The landings grew continuously till 1997, witnessed a sharp fall during 1998-2004 and then a sharp increase in the following years 2006-09 hitting the new peak of 5.39 lakh tonnes well beyond the potential yield estimate of 4.25 lakh tonnes by CMFRI. A section of the TN fishing fleet depend heavily on fishing in neighbouring waters and nearly 20% of the catch comes from South Andhra and Sri Lankan waters. Deep sea fishing is already in vogue in TN as Kanyakumari’s Thoothoor fishers with a fleet of approximately 500 long-liners cum gillnetters reigning all over the west coast and landing their catch at Kochi. Chennai gillnetters and a tiny fleet of long-liners in Puducherry have already started fishing beyond the shelf on the east coast

Bidirectional three port converter for power flow management of PV/Battery-Fed elevator system

The Bidirectional Three Port Converter (BTPC) proposed in this research work is addressed for an elevator application that is driven from a BLDC motor in all four quadrants sourced from solar Photovoltaic (PV). The converter design of a PV based system necessitates constant output voltage with high power density and efficiency. The Proposed BTPC tracks the maximum power, maintains constant output voltage and also deals with the bidirectional power flow management whenever there is a change in applied torque when the machine is switched from motoring to regenerating mode. Furthermore, single stage power conversion is achieved with power transfer from PV to dc link or battery to dc link based on the load requirement and surplus power is directly stored in the battery. Closed loop control ensures adjusting the duty cycle of the proposed converter switches thereby maintaining the bidirectional power flow management. The proposed converter is analysed in detail with operating principle, design considerations and verified in terms of simulation and through experimental results

Supplementary Papers on Fisheries Management

There are myriad laws and regulations that have some impact on marine fishing in Tamil Nadu and Puducherry. Obviously, the most important is the MFRA. Increasingly, environmental laws are having a significant impact as are regulations by seafood importing nations and trade related instruments brought in by the WTO. A major central law is also in the making. The plethoras of laws (and agencies implementing them) also mean that there is considerable overlap and lack of coherence. There is no mechanism at the moment to ensure that they all converge towards a common understanding and vision for fisheries management. An important factor that cannot be ignored is that the large traditional fishing community has its own laws and independent system of management that has a huge influence on how constitutional laws get implemented

DESIGN AND EVALUATION OF COLON SPECIFIC DRUG DELIVERY OF BUDENOSIDE

Objective: The objective of this research is to design and evaluate a colon specific drug delivery of budenoside using guar gum as enzyme dependent polymer.Methods: Matrix tablets of Budenoside were prepared by using wet granulation technique with different proportions of guar gum and evaluated for different evaluation tests and release profiles.Results: The formulations were studied for post compression parameters like hardness, friability, weight variation and drug content are in acceptable range of pharmacopoeial specifications. In vitro swelling and Invitro release studies was carried out at different pH ranges (1.2, 6.8 and 7.4). The release profile of budenoside from the matrix tablets is dependent upon the gelling property of guar gum and degradation of guar gum polysaccharide by colonic bacteria. High concentration of guar gum showed less drug release in the stomach as an enzyme dependent polymer. In vitro release data revealed that the presence of rat caecal content in dissolution medium showed the significant increase in drug release (97.12%), when compared to drug release study in absence of caecal content (76.86).Conclusion: The results were subjected to study the release kinetics. The values of correlation coefficient indicated that the drug release followed Zero order drug release kinetics with Peppas drug release mechanism. In vitro drug release studies shows that guar gum with high concentration (25%) has optimum release in a controlled manner for 24 hours.Â

Fisheries environment in the APFIC region with particular emphasis on the northern Indian Ocean

The stocks of the small pelagics in the northern Indian Ocean are governed by different environmental jactors such as wind pattern, currents, convergence, temperature, salinjty, dissolved oxygen and vertical mixing processes. An attempt is made in this paper to correlate these factors with the fisheries for the small pelagics, In the northwest Pacific Ocean, successes or failures of recruitment of pelagic fishes are related to oceanographic factors, especially the direction of Kuroshio current. The information available on these aspects has been briefly reviewe

Comparisons of precipitation measurements by the Advanced Microwave Precipitation Radiometer and multiparameter radar

Includes bibliographical references.Multiparameter microwave radar measurements are based on dual-polarization and dual-frequency techniques and are well suited for microphysical inferences of complex precipitating clouds, since they depend upon the size, shape, composition, and orientation of a collection of discrete random scatterers. Passive microwave radiometer observations represent path integrated scattering and absorption phenomena of the same scatterers. The response of the upwelling brightness temperatures TB to the precipitation structure depends on the vertical distribution of the various hydrometeors and gases, and the surface features. As a result, combinations of both active and passive techniques contain great potential to markedly improve the longstanding issue of precipitation measurement from space. The NASA airborne Advanced Microwave Precipitation Radiometer (AMPR) and the National Center for Atmospheric Research (NCAR) CP-2 multiparameter radar were jointly operated during the 1991 Convection and Precipitation/Electrification experiment (CaPE) in central Florida. The AMPR is a four channel, high resolution, across-track scanning total power radiometer system using the identical multifrequency feedhorn as the widely utilized Special Sensor Microwave/Imager (SSM/I) satellite system. Surface and precipitation features are separable based on the TB behavior as a function of the AMPR channels. The radar observations are presented in a remapped format suitable for comparison with the multifrequency AMPR imagery. Striking resemblances are noted between the AMPR imagery and the radar reflectivity at successive heights, while vertical profiles of the CP-2 products along the nadir trace suggest a storm structure consistent with the viewed AMPR TB. Directly over the storm cores, the difference between the 37 and 85 GHz TB was noted to approach (and in some cases fall below) zero. Microwave radiative transfer computations show that this is theoretically possible for hail regions suspended aloft in the core of strong convective storms.This work was supported by the NASA Earth Science and Applications Division under Grant NAG8-890. The National Center for Atmospheric Research is sponsored by the National Science Foundation