Solving the MANET Routing Problem using Ant Colony Algorithm

Mobile ad-hoc networks (MANETs) are a collection of mobile nodes communicating wirelessly without a centralized infrastructure. The biggest challenge in MANETs is to find a path between communicating nodes, that is, the MANET routing problem. The considerations of the MANET environment and the nature of the mobile nodes create further complications which results in the need to develop special routing algorithms to meet these challenges. Swarm Intelligence, a bio-inspired technique, which has proven to be very adaptable in other problem domains, has been applied to the MANET routing problem as it forms a good fit to the problem. In this thesis, a study of Ant Colony based routing algorithms is carried out taking into consideration two of the most popular algorithms Ant based algorithms, AntHocNet and the Ant Routing Algorithm (ARA). A thorough analyis of ARA is carried out based on the effect of its individual routing mechanisms on its routing efficacy. The original ARA algorithm, although finds the shortest path between source and destination, is observed to not be competitive against other MANET algorithms such as AODV in performance criteria. Based on the analysis performed, modifications are proposed to the ARA algorithm. Finally, a performance evaluation of the original ARA and the modified ARA is carried out with respect to each other, and with respect to AODV, a state of the art MANET routing algorithm vis-a-vis mobility criteria. The motivation behind the thesis is to realize application of MANETs in real world applications by solving the problem of routing

Record of the sea slug, Kalinga ornata Alder & Hancock, 1864 from the inshore waters of Bay of Bengal along Chennai coast

Sea slugs were caught in the trawl net operated off north Chennai at a depth of around 100-150 m during early hours of 24 June 2011. The specimens were classified and identified as Kalinga ornata and deposited in the Marine Biodiversity Museum of the Central Marine Fisheries Research Institute, Kochi (Accession code: DB. 40.1.1.). Although sea slugs have been found in these waters, there are limited studies on identification to the species level. Kalinga ornata was reported in India during 1936 from Kolkata and further there are no published reports on occurrence of of this species along the east coast of India

Economics and policies for open sea cage culture in Andhra Pradesh

The fisheries sector plays a significant role in providing employment, reducing poverty and promoting health. Fish is an extremely nutritious, a vital source of protein and essential nutrients. The sector provides employment opportunities to nearly 14.5 lakh people directly and indirectly in Andhra Pradesh. In recent years, sea farming is gaining popularity and a couple of finfish, shellfish species and some sea weeds are now being farmed. Ornamental fish farming also has a promising future and is likely to contribute to the overall growth of fisheries sector in the coming years. Good governance and good culture practices can enable fisheries to thrive sustainably. Therefore, the Government of Andhra Pradesh is unveiling the policy to create a suitable eco-system for the rapid growth of fisheries and aquaculture for the coming years

FPGA Based Hardware Co-Simulation of an Area and Power Efficient FIR Filter for Wireless Communication Systems

“In this paper FPGA based hardware co-simulation of an area and power efficient FIR filter for wireless communication systems is presented. The implementation is based on distributed arithmetic (DA) which substitutes multiply-and-accumulate operations with look up table (LUT) accesses. Parallel Distributed arithmetic (PDA) look up table approach is used to implement an FIR Filter taking optimal advantage of the look up table structure of FPGA using VHDL. The proposed design is hardware co-simulated using System Generator10.1, synthesized with Xilinx ISE 10.1 software, and implemented on Virtex-4 based xc4vlx25-10ff668 target device. Results show that the proposed design operates at 17.5 MHz throughput and consumes 0.468W power with considerable reduction in required resources to implement the design as compared to Coregen and add/shift based design styles. Due to this reduction in required resources the proposed design can also be implemented on Spartan-3 FPGA device to provide cost effective solution for DSP and wireless communication applications.

Impact of cloud parameterization on the numerical simulation of a super cyclone

This study examines the role of parameterization of convection and explicit moisture processes on the simulated track, intensity and inner core structure of Orissa super cyclone (1999) in Bay of Bengal (north Indian Ocean). Sensitivity experiments are carried out to examine the impact of cumulus parameterization schemes (CPS) using MM5 model (Version 3.7) in a two-way nested domain (D1 and D2) configuration at horizontal resolutions (45-15 km). Three different cumulus parameterization schemes, namely Grell (Gr), Betts-Miller (BM) and updated Kain Fritsch (KF2), are tested. It is noted that track and intensity both are very sensitive to CPS and comparatively, KF2 predicts them reasonably well. Particularly, the rapid intensification phase of the super cyclone is best simulated by KF2 compared to other CPS. To examine the effect of the cumulus parameterization scheme at high resolution (5 km), the three-domain configuration (45-15-5 km resolution) is utilized. Based on initial results, KF2 scheme is used for both the domains (D1 and D2). Two experiments are conducted: one in which KF2 is used as CPS and another in which no CPS is used in the third domain. The intensity is well predicted when no CPS is used in the innermost domain. The sensitivity experiments are also carried out to examine the impact from microphysics parameterization schemes (MPS). Four cloud microphysics parameterization schemes, namely mixed phase (MP), Goddard microphysics with Graupel (GG), Reisner Graupel (RG) and Schultz (Sc), are tested in these experiments. It is noted that the tropical cyclone tracks and intensity variation have considerable sensitivity to the varying cloud microphysical parameterization schemes. The MPS of MP and Sc could very well capture the rapid intensification phase. The final intensity is well predicted by MP, which is overestimated by Sc. The MPS of GG and RG underestimates the intensity