Studies on Rubber Composition as Passive Acoustic Materials in Underwater Electro Acoustic Tranducer Technology and Their aging Characteristic

The research work has been in the area of compounding and characterization of rubbers for use in under water electro acoustic transducers. The study also covers specific material system such as encapsulation materials, baffle material, seal material, etc. Life prediction techniques of under water rubbers in general have been established with reference to more than one functional property. Ranges of passive materials, besides the active sensing material go into the construction of underwater electro acoustic transducers. Reliability of the transducer is critically dependent on these passive materials. Rubbers are a major class of passive materials. The present work concentrates on these materials. Conventional rubbers are inadequate to meet many of the stringent function specific requirements. There exists a large gap of information in the rubber technology of underwater rubbers, particularly relating to underwater electro acoustic transducers. This study is towards filling up the gaps of information in this crucial area. Water intake into rubber is considered as the single most important issue for the long-term performance of rubbers, especially Neoprene. In this study, the cause and effects of a range of parameters affecting the water absorption by diffusion and permeation have been investigated.

Studies on rubber compositions as passive acoustic materials in underwater electro acoustic transducer technology-and their aging characteristics

Rubber has become an indispensable material in Ocean technology. Rubber components play critical roles such as sealing, damping, environmental protection, electrical insulation etc. in most under water engineering applications. Technology driven innovations in electro acoustic transducers and other sophisticated end uses have enabled quantum jump in the quality and reliability of rubber components. Under water electro acoustic transducers use rubbers as a critical material in their construction. Work in this field has lead to highly reliable and high performance materials which has enhanced service life of transducers to the extent of 1015 years. Present work concentrates on these materials. Conventional rubbers are inadequate to meet many of the stringent functional of the requirements. There exists large gap of information in the rubber technology of under water rubbers, particularly in the context of under water electro acoustic transducers. Present study is towards filling up the gaps of information in this crucial area. The research work has been in the area of compounding and characterisation of rubbers for use in under water electro acoustic transducers. The study also covers specific material system such as encapsulation material, baffle material, seal material, etc. Life prediction techniques of under water rubbers in general has been established with reference to more than one functional property. This thesis is divided into 6 chapters.

Science and technology of rubber reclamation with special attention to NR-based waste latex products

A comprehensive overview of reclamation of cured rubber with special emphasis on latex reclamation is depicted in this paper. The latex industry has expanded over the years to meet the world demands for gloves, condoms, latex thread, etc. Due to the strict specifications for the products and the unstable nature of the latex as high as 15% of the final latex products are rejected. As waste latex rubber (WLR) represents a source of high-quality rubber hydrocarbon, it is a potential candidate for generating reclaimed rubber of superior quality. The role of the different components in the reclamation recipe is explained and the reaction mechanism and chemistry during reclamation are discussed in detail. Different types of reclaiming processes are described with special reference to processes, which selectively cleave the cross links in the vulcanized rubber. The state-of-the-art techniques of reclamation with special attention on latex treatment are reviewed. An overview of the latest development concerning the fundamental studies in the field of rubber recycling by means of low-molecular weight compounds is described. A mathematical model description of main-chain and crosslink scission during devulcanization of a rubber vulcanizate is also given.

Adoption of Technology-Enabled Banking Self-Services: Antecedents and Consequences

School of Management Studies, Cochin University of Science and Technology

Impact of Information Communication Technology (ICT) on Professional Development and Educational Needs of Library Professionals in the Universities of Kerala

The shift from print to digital information has a high impact on all components of the academic library system in India especially the users, services and the staff. Though information is considered as an important resource, the use of ICT tools to collect and disseminate information has been in a slow pace in majority of the University libraries This may be due to various factors like insufficient funds, inadequate staff trained in handling computers and software packages, administrative concerns etc. In Kerala, automation has been initiated in almost all University libraries using library automation software and is under different stages of completion. There are not much studies conducted about the effects of information communication technologies on the professional activities of library professionals in the universities in Kerala. It is important to evaluate whether progress in ICT has had any impact on the library profession in these highest educational institutions. The aim of the study is to assess whether the developments in information communication technologies have any influence on the library professionals’ professional development, and the need for further education and training in the profession and evaluate their skills in handling developments in ICT. The total population of the study is 252 including the permanently employed professional library staff in central libraries and departmental libraries in the main campuses of the universities under study. This is almost a census study of the defined population of users. The questionnaire method was adopted for collection of data for this study, supplemented by interviews of Librarians to gather additional information. Library Professionals have a positive approach towards ICT applications and services in Libraries, but majority do not have the opportunities to develop their skills and competencies in their work environment. To develop competitive personnel in a technologically advanced world, high priority must be given to develop competence in ICT applications, library management and soft skills in library professionals, by the University administrators and Library associations. Library science schools and teaching departments across the country have to take significant steps to revise library science curriculum, and incorporate significant changes to achieve the demands and challenges of library science profession.

Studies on Heat Diffusion in Selected Conducting Polymers using Probe Beam Deflection and Photoacoustic Techniques

In the present study, radio frequency plasma polymerization technique is used to prepare thin films of polyaniline, polypyrrole, poly N-methyl pyrrole and polythiophene. The thermal characterization of these films is carried out using transverse probe beam deflection method. Electrical conductivity and band gaps are also determined. The effect of iodine doping on electrical conductivity and the rate of heat diffusion is explored.Bulk samples of poyaniline and polypyrrole in powder form are synthesized by chemical route. Open photoacoustic cell configuration is employed for the thermal characterization of these samples. The effect of acid doping on heat diffusion in these bulk samples of polyaniline is also investigated. The variation of electrical conductivity of doped polyaniline and polypyrrole with temperature is also studied for drawing conclusion on the nature of conduction in these samples. In order to improve the processability of polyaniline and polypyrrole, these polymers are incorporated into a host matrix of poly vinyl chloride. Measurements of thermal diffusivity and electrical conductivity of these samples are carried out to investigate the variation of these quantities as a function of the content of polyvinyl chloride.

Analysis and Optimization of Machining Process Using Evolutionary Algorithms

To ensure quality of machined products at minimum machining costs and maximum machining effectiveness, it is very important to select optimum parameters when metal cutting machine tools are employed. Traditionally, the experience of the operator plays a major role in the selection of optimum metal cutting conditions. However, attaining optimum values each time by even a skilled operator is difficult. The non-linear nature of the machining process has compelled engineers to search for more effective methods to attain optimization. The design objective preceding most engineering design activities is simply to minimize the cost of production or to maximize the production efficiency. The main aim of research work reported here is to build robust optimization algorithms by exploiting ideas that nature has to offer from its backyard and using it to solve real world optimization problems in manufacturing processes.In this thesis, after conducting an exhaustive literature review, several optimization techniques used in various manufacturing processes have been identified. The selection of optimal cutting parameters, like depth of cut, feed and speed is a very important issue for every machining process. Experiments have been designed using Taguchi technique and dry turning of SS420 has been performed on Kirlosker turn master 35 lathe. Analysis using S/N and ANOVA were performed to find the optimum level and percentage of contribution of each parameter. By using S/N analysis the optimum machining parameters from the experimentation is obtained.Optimization algorithms begin with one or more design solutions supplied by the user and then iteratively check new design solutions, relative search spaces in order to achieve the true optimum solution. A mathematical model has been developed using response surface analysis for surface roughness and the model was validated using published results from literature.Methodologies in optimization such as Simulated annealing (SA), Particle Swarm Optimization (PSO), Conventional Genetic Algorithm (CGA) and Improved Genetic Algorithm (IGA) are applied to optimize machining parameters while dry turning of SS420 material. All the above algorithms were tested for their efficiency, robustness and accuracy and observe how they often outperform conventional optimization method applied to difficult real world problems. The SA, PSO, CGA and IGA codes were developed using MATLAB. For each evolutionary algorithmic method, optimum cutting conditions are provided to achieve better surface finish.The computational results using SA clearly demonstrated that the proposed solution procedure is quite capable in solving such complicated problems effectively and efficiently. Particle Swarm Optimization (PSO) is a relatively recent heuristic search method whose mechanics are inspired by the swarming or collaborative behavior of biological populations. From the results it has been observed that PSO provides better results and also more computationally efficient.Based on the results obtained using CGA and IGA for the optimization of machining process, the proposed IGA provides better results than the conventional GA. The improved genetic algorithm incorporating a stochastic crossover technique and an artificial initial population scheme is developed to provide a faster search mechanism. Finally, a comparison among these algorithms were made for the specific example of dry turning of SS 420 material and arriving at optimum machining parameters of feed, cutting speed, depth of cut and tool nose radius for minimum surface roughness as the criterion. To summarize, the research work fills in conspicuous gaps between research prototypes and industry requirements, by simulating evolutionary procedures seen in nature that optimize its own systems.

Fundamental Approach to Valuation of Securities -A Study with reference to Information Technology(IT) Sector Shares in Indian Stock Market

Department of Applied Economics,Cochin University of Science and Technology

Bioprocess Technology for Antagonistic Pseudomonas MCCB 102, 103,Micrococcus MCCB 104, and Evaluation of Synechocystis MCCB 114, 115 as Probiotics for the Management of Vibrio in Shrimp Culture Systems

National Centre for Aquatic Animal Health, School of Environmental Studies, Cochin University of Science and Technology

Apptication of Biofloc Technology (BFI) in Ihe nunery rearing and farming of giant freshwater prawn, Macrobrachillm rosenbergii (de Man)

This thesis Entitled Application of Biofloc technology (BFT) In the Nursery Rearing and Farming of Giant Freshwater Prawn,Macrobrachium Rosenbergii(De Man). Aquaculture, rearing plants and animals under controlled conditions is growing with an annual growth rate of 8.3% in the period 1970-2008 (FAO, 2010). This trend of growth is essential for the supply of protein-rich food for ever increasing world population. But growth and development of aquaculture should be in sustainable manner, preferably without jeopardizing the aquatic environment.In the present study, the application of BFT in the nursery rearing and farming ofgiant freshwater prawn, M. rosenbergii, is attempted. The result of the study is organised into eight chapters. In the first chapter, the subject is adequately introduced. Various types of aquaculture practices followed, development and status of Indian aquaculture, present status of freshwater pravm culture, BF T and its use for the sustainable aquaculture systems, theory of BFT based aquaculture practices, hypothesis, objective and outline of the thesis are described. An extensive review of literature on studies carried out so far on biofloc based aquaculture are given in chapter 2. The third chapter deals with the application of BFT in the primary nursery phase of freshwater prawn. Several workers suggested the need for an intermediate nursery phase in the culture system of freshwater prawn for the successful production. Thirty day experiment was conducted to study the effect of BFT on the water quality, and animal welfare under the various stocking densities. The study concluded that stocking finfishes in biofloc-based monoculture system of freshwater prawns has the potential of increasing total yield. Prawns having a higher commercial value than finfishes besides ensuring economic sustainability. Results showed that prawn yield and survival was better in catla dominated tanks. Based on the results of the study, it is recommended to incorporate 25% rohu and 75% catla in the biofloc-based culture system of giant freshwater prawns. The results of the present study also recommend to stock relatively larger catla for biofloc-based culture system. Fish production was also higher in the 100% catla tank. When catla was added in higher percentages it should ensured that the hiding objects in the culture ponds shall be used in order to reduce the chance of cannibalism among prawns. rohu and catla equally have the ability to harvest the biofloc, catla consumes the planktonic contributes in the floc whereas rohu grazed on the bacterial consortium suspended in the water column. In Chapter 8, recommendations and future research perspectives in the field of biofloc based aquaculture is presented.