Abstract: | When variables in time series context are non-negative, such as for volatility, survival time or wave heights, a multiplicative autoregressive model of the type Xt = Xα t−1Vt , 0 ≤ α < 1, t = 1, 2, . . . may give the preferred dependent structure. In this paper, we study the properties of such models and propose methods for parameter estimation. Explicit solutions of the model are obtained in the case of gamma marginal distribution |
Description: | Statistics and Probability Letters 82 (2012) 1530–1537 |
URI: | http://dyuthi.cusat.ac.in/purl/4725 |
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Product autoreg ... non-negative variables.pdf | (260.7Kb) |
Abstract: | In the present studies it is clear that Bacillus pumilus xylanase is having the characteristic suited for an industrial enzyme (xylanases that are active and stable at elevated temperatures and alkaline pH are needed). SSF production of xylanases and its application appears to be an innovative technology where the fermented substrate is the enzyme source that is used directly in the bleaching process without a prior downstream processing. The direct use of SSF enzymes in bleaching is a relatively new biobleaching approach. This can certainly benefit the bleaching process to lower the xylanase production costs and improve the economics and viability of the biobleaching technology. The application of enzymes to the bleaching process has been considered as an environmentally friendly approach that can reduce the negative impact on the environment exerted by the use of chlorine-based bleaching agents. It has been demonstrated that pretreatment of kraft pulp with xylanase prior to bleaching (biobleaching) can facilitate subsequent removal of lignin by bleaching chemicals, thereby, reducing the demand for elemental chlorine or improving final paper brightness. Using this xylanase pre-treatment, has resulted in an increased of brightness (8.5 Unit) when compared to non-enzymatic treated bleached pulp prepared using identical conditions. Reduction of the consumption of active chlorine can be achieved which results in a decrease in the toxicity, colour, chloride and absorbable organic halogen (AOX) levels of bleaching effluents. The xylanase treatment improves drainage, strength properties and the fragility of pulps, and also increases the brightness of pulps. This positive result shows that enzyme pre-treatment facilitates the removal of chromophore fragments of pulp there by making the process more environment friendly |
URI: | http://dyuthi.cusat.ac.in/purl/935 |
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Dyuthi-T0205.pdf | (11.69Mb) |
Abstract: | The continually growing worldwide hazardous waste problem is receiving much attention lately. The development of cost effective, yet efficient methods of decontamination are vital to our success in solving this problem.Bioremediation using white rot fungi, a group of basidiomycetes characterized by their ability to degrade lignin by producing extracellular LiP, MnP and laccase have come to be recognized globally which is described in detail in Chapter 1.These features provide them with tremendous advantages over other micro-organisms.Chapter 2 deals with the isolation and screening of lignin degrading enzyme producing micoro-organisms from mangrove area. Marine microbes of mangrove area has great capacity to tolerate wide fluctuations of salinitie.Primary and secondary screening for lignin degrading enzyme producing halophilic microbes from mangrove area resulted in the selection of two fungal strains from among 75 bacteria and 26 fungi. The two fungi, SIP 10 and SIP ll, were identified as penicillium sp and Aspergillus sp respectively belonging to the class Ascomycetes .Specific activity of the purified LiP was 7923 U/mg protein. The purification fold was 24.07 while the yield was 18.7%. SDS PAGE of LiP showed that it was a low molecular weight protein of 29 kDa.Zymogram analysis using crystal violet dye as substrate confirmed the peroxidase nature of the purified LiP.The studies on the ability of purified LiP to decolorize different synthetic dyes was done. Among the dyes studied, crystal violet, a triphenyl methane dye was decolorized to the greatest extent. |
Description: | Biochemical Processing Division, Regional Research Laboratory, Trivandrum |
URI: | http://dyuthi.cusat.ac.in/purl/3116 |
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Dyuthi-T1090.pdf | (2.572Mb) |
Abstract: | In this thesis, the production and characterization of ligninolytic enzymes using the fungi isolated from mangrove area are studied. The objective of the present work are isolation and screening of dye decolorizing micro-organisms from mangrove area, screening of the selected microorganisms for the production of lignin degrading enzymes, identification of the potent micro-organisms, characterization of the crude enzyme, lignin peroxidase, of the selected fungi—Aspergillus sp. SIP 11 and Penicillium sp. SIP 10 etc. This included the determination of the optimum pH, temperature, veratryl alcohol and H2O2 concentration. Besides the stability of crude LiP at different pHs and temperatures were studied. The immense applications, particularly in bioremediation, to which the lignin degrading micro-organisms could be used make this study important, the ascomycetes and deuteromycetes fungi, especially form the marine environment were studied with respect to their ligninolytic enzyme system making this study an initial step in unraveling the vast hidden potential of these microbes in bioremediation, the marine microbes are halophilic in nature which make them better suited to cope with the high salinity of industrial effluents thereby giving them added advantage in the filed of bioremediation. The thesis deals with the isolation and screening of lignin degrading enzyme-producing microbes from mangrove area. The identification of the most potent fungal isolates and characterization of LiP from these are also done. |
URI: | http://dyuthi.cusat.ac.in/purl/24 |
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Dyuthi-T0181.pdf | (5.171Mb) |
Abstract: | This thesis presents a detailed account of a cost - effective approach towards enhanced production of alkaline protease at profitable levels using different fermentation designs employing cheap agro-industrial residues. It involves the optimisation of process parameters for the production of a thermostable alkaline protease by Vibrio sp. V26 under solid state, submerged and biphasic fermentations, production of the enzyme using cell immobilisation technology and the application of the crude enzyme on the deproteinisation of crustacean waste.The present investigation suggests an economic move towards Improved production of alkaline protease at gainful altitudes employing different fermentation designs utilising inexpensive agro-industrial residues. Moreover, the use of agro-industrial and other solid waste substrates for fermentation helps to provide a substitute in conserving the already dwindling global energy resources. Another alternative for accomplishing economically feasible production is by the use of immobilisation technique. This method avoids the wasteful expense of continually growing microorganisms. The high protease producing potential of the organism under study ascertains their exploitation in the utilisation and management of wastes. However, strain improvement studies for the production of high yielding variants using mutagens or by gene transfer are required before recommending them to Industries.Industries, all over the world, have made several attempts to exploit the microbial diversity of this planet. For sustainable development, it is essential to discover, develop and defend this natural prosperity. The Industrial development of any country is critically dependent on the intellectual and financial investment in this area. The need of the hour is to harness the beneficial uses of microbes for maximum utilisation of natural resources and technological yields. Owing to the multitude of applications in a variety of industrial sectors, there has always been an increasing demand for novel producers and resources of alkaline proteases as well as for innovative methods of production at a commercial altitude. This investigation forms a humble endeavour towards this perspective and bequeaths hope and inspiration for inventions to follow. |
URI: | http://dyuthi.cusat.ac.in/purl/2482 |
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Dyuthi-T0665.pdf | (11.57Mb) |
Abstract: | The overall objective of the present study was to develop a novel and economic reclaiming process that does not adversely affect the quality of rubber and to investigate methods of utilising the reclaim. Since waste latex products represent a potential source of high quality rubber hydrocarbon, it was decided to develop a process based on such latex wastes. The study revealed that latex reclaim could replace raw natural rubber upto about 50 per cent of its weight without any serious deterioration in mechanical properties. |
Description: | Department of Polymer Science and Rubber Technology, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3501 |
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Dyuthi-T1454.pdf | (3.085Mb) |
Abstract: | Fatty acids are the basic building blocks fats and lipids are made of. Fatty acids found in foods and fats stored in the body are mainly in the form oftriacylglycerols (TAGs), a glycerol molecule backbone to which three (termed sn-1; sn-2 and sn-3), often different, fatty acids are attached Figure 1-1 (A). Fatty acids are made up of a backbone of carbon atoms, with a carboxyl group (COOH) at one end [the delta (Δ) end] and a methyl group (CH3) at another end [the omega (ω) or n-end] (Figure 1-1 (B). Hydrogen atoms are joined to the sequence of carbon atoms, forming a hydrocarbon chain. Carbon chain length and presence and absence of a double bond between the carbon atoms influence the characteristics of a fatty acid such as melting point and digestibility. Based on the bonding nature, they are divided into saturated fatty acid (SFA)- carbons in the fatty acid chain are linked by single bonds; monounsaturated fatty acid (MUFA)- only one double bond present in fatty acid chain and polyunsaturated fatty acid (PUFA) more than one double bond present in the fatty acid chain |
URI: | http://dyuthi.cusat.ac.in/purl/5158 |
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Dyuthi-T2192.pdf | (38.30Mb) |
URI: | http://dyuthi.cusat.ac.in/purl/726 |
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Sreeja chellapp ... urification...,Oct2005.PDF | (4.854Mb) |
Abstract: | Engyodontium album isolated from marine sediment produced protease, which was active at pH 11. Process parameters influencing the production of alkaline protease by marine E. album was optimized. Particle size of <425 mm, 60% initial moisture content and incubation at 25 8C for 120 h were optimal for protease production under solid state fermentation (SSF) using wheat bran. The organism has two optimal pH (5 and 10) for maximal enzyme production. Sucrose as carbon source, ammonium hydrogen carbonate as additional inorganic nitrogen source and amino acid leucine enhanced enzyme production during SSF. The protease was purified and partially characterized. A 16-fold purified enzyme was obtained after ammonium sulphate precipitation and ion-exchange chromatography. Molecular weight of the purified enzyme protein was recorded approximately 38 kDa by SDS-PAGE. The enzyme showed maximum activity at pH 11 and 60 8C. Activity at high temperature and high alkaline pH suggests suitability of the enzyme for its application in detergent industry |
Description: | Process Biochemistry 41 (2006) 956–961 |
URI: | http://dyuthi.cusat.ac.in/purl/4242 |
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Production, pur ... lid state fermentation.pdf | (261.6Kb) |
Abstract: | Marine fungi remain totally unexplored as a source of industrial enzyme and prospective applications. Further tannase production by a marine organism has so far not been established. The primary objective of this study included the evaluation of the potential of Aspergillus awamori isolated from sea water as part of an earlier study and available in the culture collection of the Microbial technology laboratory for tannase production through different fermentation methods, optimization of bioprocess variables by statistical methods, purification and characterization of the enzyme, genetic study, and assessment of its potential applications. |
Description: | Department of Biotechnology, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/xmlui/purl/2020 |
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Dyuthi-T0443.pdf | (5.194Mb) |
URI: | http://dyuthi.cusat.ac.in/purl/5176 |
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Dyuthi-T2211.pdf | (42.98Mb) |
Abstract: | The library professional in an academic institution has to anticipate the changing expectations of the users, and be flexible in adopting new skills and levels of awareness. Technology has drastically changed the way librarians define themselves and the way they think about their profession and the institutions they serve. In addition to the technical and professional skills, commitment to user centred services and skills for effective oral and written communication; they must have other skills, including business and management, teaching, leadership, etc. Eventually, library and information professionals in academic libraries need to update their knowledge and skills in Information and Communication Technology (ICT) as they play the role of key success factor in enabling the library to perform its role as an information support system for the society. |
Description: | Library 2.0 and Information Management,2011 |
URI: | http://dyuthi.cusat.ac.in/purl/3985 |
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Professional As ... ibrarianship in Kerala.pdf | (3.465Mb) |
Abstract: | The paper aims to bring out the problems and prospects of the professional development opportunities of academic library professionals in the Universities in Kerala. The study is a part of research undertaken to survey the professional development activities and educational needs of library professionals in the major Universities of Kerala because of the developments in Information communication technology. The study recommends methods for improving the knowledge/skills of library professionals. The aim of the study is to evaluate the professional development activities of Library professionals and their attitude towards continuing education programmes. In order to achieve the objectives of the study a survey was conducted with the help of structured questionnaires distributed to 203 library professionals in seven major universities in Kerala, (South India) of which 185 questionnaires were returned. Results of the analysis show that majority of the professionals have pursued higher degrees in library science or IT allied courses after entering the profession, and that they have a positive attitude towards participation in training programmes and workshops. The results show that developments in ICT have a positive influence on majority of library professionals‘ attitude towards continuing education programmes. |
Description: | Asia-Pacific Conference on Library & Information Education & Practice, 2011 |
URI: | http://dyuthi.cusat.ac.in/purl/4468 |
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Professional De ... rofessionals in Kerala.pdf | (305.8Kb) |
Abstract: | This is a study on “Professional Services: Civil Liability for Deficiency”. This study is made with special reference to medical profession. The importance of qualitative professional services does not require any emphasis. It is a matter of great concern for the people as they are consumers.This study is divided into 12 chapters. The introductory chapter deals with characteristics of profession, basis of professional liability and international efforts to check abuse of position by professional men. Consumers as laymen can not perceive the intricacies of professional services. As a result professional men could misuse their superior position to expose consumers to hardship through deficient services. This is obvious from the fact that deficiency in professional services has assumed a menacing proportion. It is indicative of failure of internal control through self-regulation to check the abuse of position by the professional men. The professional bodies entrusted with the task of enforcing disciplinary measures show a very callous and indifferent attitude towards the repressive conduct of their members. These bodies are more concerned to protect the interest of their members. They are not free from institutional bias. They have put the interest of consumers into oblivion. In effect remedies through professional bodies has become a myth. All these factors make the external control of professional services mandatory to protect the consumers from the clutches of unscrupulous professional men, who abuse their superior position. The professional men who abuse their position are exposed to liability. Their liability arises under contract, tort and statutory law. The present study substantially concentrates on professional liability of medical men. The obvious reason is that of all professional services medical services are the frequently availed services by the consumers. Medical negligence cases account for bulk of the professional negligence cases. ln India also large number of cases are coming before consumer forae. The legal principles evolved in this sphere of professional service confers an insight into legal control of other professional services as well. The same principles are applied to other professions also, as by and large all the professions share common characteristics. Such principles are modified wherever necessary to make room for differential aspects of particular profession |
Description: | School of Legal Studies, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3139 |
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Dyuthi-T1113.pdf | (26.99Mb) |
Abstract: | This study deals the professional Services civil Liability for deficiency with special reference to medical professionals.the study deals with the characteristics of profession,basis of liability , historical evolution of legal controls on professional services, liability of doctors for negligence under tort law. Expectations to liability for medical negligence are critically evaluated. consent of medical treatment etc are studied |
Description: | Department of Legal studies |
URI: | http://dyuthi.cusat.ac.in/purl/3024 |
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Dyuthi-T1002.pdf | (26.99Mb) |
Abstract: | Development of new technologies in the field of library and information science especially in academic libraries has resulted in the need for library staff to be flexible in adopting new skills and levels of awareness. In addition to core technology skills, importance is to be given to other skills in communication, management, etc. This paper attempts to describe in brief the competencies and skills required for an academic library professional in the digital era . |
Description: | Recent Trends In Libraries,2010 |
URI: | http://dyuthi.cusat.ac.in/purl/3986 |
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Professional Sk ... ElectronicEnvironment.pdf | (2.403Mb) |
Abstract: | The objective of this study is to assess the changes that have been taking place in the socio-economic profile of organized industrial workers of Kerala in the context of the changes that have been taking place in the state's industrial structure. with this object in view, the study seeks to find out the similarities and differences in the profile of workers belonging to two Segments of factory sector industries in Kerala viz., modern and traditional segments. It also seeks to examine the factors leading to the differences in profile, if any, and their consequences. As noted earlier, the profile of workers may be influenced both by external societal factors and by internal factors like the difference in industrial structure and the technologies used. It is proposed to assess the relative importance of these two groups of factors. In drawing up the profile, we seek to find out whether the workers belonging to the organised sector of industry in Kerala particularly the more modern sector have begun to form a ‘select group‘ in the Kerala society and the total work force. Wherever possible, it is proposed to compare the profile of the Kerala workers with those of workers in other states of India. As an incidental objective, it is also proposed to find out to the extent possible, whether trends towards labour embourgeoisement and class shifting have begun to set in among the industrial workers of Kerala, particularly among the workers in the modern industries as a result of their relative affluence and their middle class socioeconomic background. besides, the study seeks to find out whether there is any difference in the class consciousness of workers belonging to these two segments of organized industry, arising from the differences in their economic status and social background. |
Description: | Department Of Applied Economics Cochin University Of Science And Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3562 |
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Dyuthi-T1544.pdf | (10.02Mb) |
Abstract: | In this century, computers have become an inseparable part of human life. Human beings entrust them with day-to-day activities and as well as highly sensitive data such as credit card information. Therefore, it is highly essential to ensure the proper working of the software before it is handed over to the users. Simple errors in the software may cause billions of dollar loss or even cause harm to human life. Therefore, the software needs to be dependable and reliable. Software testing is one of the most important methods to assure an error free software. This thesis work is centered on software testing. One of the major concerns in today’s practical software testing is the size of the source code which the testers have to deal with. Simple and effective testing methods that can handle the issue of source code length are highly essential. As the length of the program increases, testing activities like test case generation and test execution becomes more complicated. From the literature review it was evident that most of the existing methods for software testing did not address the problem of source code size during testing. Considering these scenarios, the work presented in this thesis tries to handle these challenges in practical software testing so as to make testing easier. With this aim, we have proposed a forward slicing based framework which helps to identify the statements of relevance in a software. Program slicing is used in several fields like program comprehension, debugging, software maintenance, program cohesion, refactoring and reverse engineering. Anyhow, the works that explicitly demonstrate how program slicing may be applied in software testing is extremely rare. In this thesis, we have clearly demonstrated how to perform software testing and trace dependencies in the source code using forward slicing. A formal representation of forward slicing is also presented in this work. As an extension to our forward slicing framework, we have also introduced the concept of partitioned forward slices and partial slices which helps the testers to focus on statements of interest. Partitioned forward slices helps to handle the large size of forward slices whereas partial slices identifies statements of interest with respect to output variables. The research finding finally concludes that, software testing approaches should incorporate slicing methods to make testing more effective and easier. |
URI: | http://dyuthi.cusat.ac.in/purl/5212 |
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Dyuthi T-2247.pdf | (3.484Mb) |
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