| Abstract: | The present thesis work focuses on hole doped lanthanum manganites and their thin film forms. Hole doped lanthanum manganites with higher substitutions of sodium are seldom reported in literature. Such high sodium substituted lanthanum manganites are synthesized and a detailed investigation on their structural and magnetic properties is carried out. Magnetic nature of these materials near room temperature is investigated explicitly. Magneto caloric application potential of these materials are also investigated. After a thorough investigation of the bulk samples, thin films of the bulk counterparts are also investigated. A magnetoelectric composite with ferroelectric and ferromagnetic components is developed using pulsed laser deposition and the variation in the magnetic and electric properties are investigated. It is established that such a composite could be realized as a potential field effect device. The central theme of this thesis is also on manganites and is with the twin objectives of a material study leading to the demonstration of a device. This is taken up for investigation. Sincere efforts are made to synthesize phase pure compounds. Their structural evaluation, compositional verification and evaluation of ferroelectric and ferromagnetic properties are also taken up. Thus the focus of this investigation is related to the investigation of a magnetoelectric and magnetocaloric application potentials of doped lanthanum manganites with sodium substitution. Bulk samples of sodium substituted lanthanum manganites. Bulk samples of sodium substituted lanthanum manganites with Na substitution ranging from 50 percent to 90 percent were synthesized using a modified citrate gel method and were found to be orthorhombic in structure belonging to a pbnm spacegroup. The variation in lattice parameters and unit cell volume with sodium concentration were also dealt with. Magnetic measurements revealed that magnetization decreased with increase in sodium concentrations. |
| URI: | http://dyuthi.cusat.ac.in/purl/4929 |
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| Dyuthi-T2009.pdf | (10.33Mb) |
| Abstract: | In this paper an attempt has been made to determine the number of Premature Ventricular Contraction (PVC) cycles accurately from a given Electrocardiogram (ECG) using a wavelet constructed from multiple Gaussian functions. It is difficult to assess the ECGs of patients who are continuously monitored over a long period of time. Hence the proposed method of classification will be helpful to doctors to determine the severity of PVC in a patient. Principal Component Analysis (PCA) and a simple classifier have been used in addition to the specially developed wavelet transform. The proposed wavelet has been designed using multiple Gaussian functions which when summed up looks similar to that of a normal ECG. The number of Gaussians used depends on the number of peaks present in a normal ECG. The developed wavelet satisfied all the properties of a traditional continuous wavelet. The new wavelet was optimized using genetic algorithm (GA). ECG records from Massachusetts Institute of Technology-Beth Israel Hospital (MIT-BIH) database have been used for validation. Out of the 8694 ECG cycles used for evaluation, the classification algorithm responded with an accuracy of 97.77%. In order to compare the performance of the new wavelet, classification was also performed using the standard wavelets like morlet, meyer, bior3.9, db5, db3, sym3 and haar. The new wavelet outperforms the rest |
| Description: | Power, Signals, Controls and Computation (EPSCICON), 2012 International Conference on,pp 1-5 |
| URI: | http://dyuthi.cusat.ac.in/purl/4526 |
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| Towards the dev ... for ECG classification.pdf | (387.0Kb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5310 |
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| Dyuthi T-2346.pdf | (3.393Mb) |
| Abstract: | Page 1. Towards Web 3.0... • Web 1.0 • Web 2.0 • Web 3.0 • Technology hype? • Internet as seen by our kids? Page 2. Random Trivia: Brazil has more Orkut users than citizens Page 3. The war is over. Platforms have won. Applications have lost Page 4. Page 5. Blogosphere • The blogosphere is made up of all blogs and their interconnections Page 6. Social bookmarking Page 7. Page 8. Page 9. Page 10. Page 11. Page 12. Page 13. Page 14. Towards Web 3.0 Page 15. Page 16. Wolfram Alpha Page 17. Page 18. Page 19. Page 20. Page 21. Page 22 |
| URI: | http://dyuthi.cusat.ac.in/purl/4171 |
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| Towards Web 3.0....pdf | (2.563Mb) |
| Description: | Dept.of Marine Biology, Microbiology and Biochemistry, School of Marine Sciences, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/2152 |
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| Dyuthi-T0511.pdf | (11.96Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/1215 |
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| Prabhudeva K N 1988.PDF | (320.3Kb) |
| Abstract: | In this thesis certain important aspects of heavy metal toxicity have been worked out. Recent studies have clearly shown that when experimental media contained more than one heavy metals, such metals could conspicuously influence the toxic reaction of the animals both in terms of quantity and nature. The experimental results available on individual metal toxicity show that, in majority of such results, unrealistically high concentrations of dissolved metals are involved. A remarkable number of factors have been shown to influence metal toxicity such as various environmental factors particularly temperature and salinity, the condition of the organism and the ability of some of the marine organisms to adapt to metallic contamination. Further, some of the more sensitive functions like embryonic and larval development, growth and fecundity, oxygen utilization and the function of various enzymes are found to be demonstrably sensitive in the presence of heavy metals. However, some of the above functions could be compensated for by adaptive process. If it is assumed that the presence of a single metal in higher concentrations could affect the life function of marine animals, more than one metal in the experimental media should manifest such effects in a greater scale. Commonly known as synergism or more than additivity, majority of heavy metals bring about synergistic reaction .The work presented in this thesis comprises lethal and sublethal toxicities of different salt forms of copper and silver on the brown mussel Perna indica. during the present investigation sublethal concentrations of copper and silver in their dent effects on survival, oxygen consumption, filtration, accumulation and depuration on Perna indica. The results are presented under different sections to make the presentation meaningful . |
| Description: | Division of Marine Biology, Microbiology and Biochemistry, School of Marine Sciences, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3223 |
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| Dyuthi-T1197.pdf | (7.001Mb) |
| Abstract: | Toxicity of effluent from a titanium dioxide factory containing sulphuric acid residue with soluble iron metallic salts and insoluble material such as silica, etc. on fishes, decapods and molluscs was studied. The effluent caused changes in pH and oxygen depletion of the sea water. Sublethal effects of the precipitate of ferrous salts were also studied. Dilutions of effluent up to 1:150 were LC100 for all organisms used while 1:200 dilution was LC50 for fishes at 36 hr and for other organisms at 48 hr. But death of organisms at this concentration was caused by pH changes and oxygen depletion and did not account for the effects of the precipitate. Below this level precipitation started soon after mixing with sea water causing death of organisms by choking their gills and siphons. Dilutions,< 1:1000 were 96 hr LCO. |
| URI: | http://dyuthi.cusat.ac.in/purl/1545 |
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| toxicity of eff ... on some marine animals.PDF | (1.307Mb) |
| Abstract: | This article present the result from a study of two sediment cores collected from the environmentally distinct zones of CES. Accumulation status of five toxic metals: Cadmium (Cd), Chromium (Cr), Cobalt (Co), Copper (Cu) and Lead (Pb) were analyzed. Besides texture and CHNS were determined to understand the composition of the sediment. Enrichment Factor (EF) and Anthropogenic Factor (AF) were used to differentiate the typical metal sources. Metal enrichment in the cores revealed heavy load at the northern (NS1 ) region compared with the southern zone (SS1). Elevation of metal content in core NS1 showed the industrial input. Statistical analyses were employed to understand the origin of metals in the sediment samples. Principal Component Analysis (PCA) distinguishes the two zones with different metal accumulation capacity: highest at NS1 and lowest at SS1. Correlation analysis revealed positive significant relation only in core NS1, adhering to the exposition of the intensified industrial pollution |
| Description: | Int. J. Environ. Res., 8(1):133-138,Winter 2014 |
| URI: | http://dyuthi.cusat.ac.in/purl/4614 |
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| Toxic Metal Dis ... Estuarine System (CES).pdf | (130.1Kb) |
| Abstract: | Concentrations and distributions of trace metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in surficial sediments of the Cochin backwaters were studied during both monsoon and pre-monsoon periods. Spatial variations were in accordance with textural charaterstics and organic matter content. A principal component analysis distinguished three zones with different metal accumulation capacity: (i) highest levels in north estuary, (ii) moderate levels in central zone, and (iii) lowest levels in southern part. Trace metal enrichments are mainly due to anthropogenic contribution of industrial, domestic, and agricultural effluents, whose effect is enhanced by settling of metals due to organic flocculation and inorganic precipitation associated with salinity changes. Enrichments factors using Fe as a normalizer showed that metal contamination was the product of anthropogenic activities. An assessment of degree of pollution-categorized sediments as moderately polluted with Cu and Pb, moderately-to-heavily polluted with Zn, and heavily-to-extremely polluted with Cd. Concentrations at many sites largely exceed NOAA ERL (e.g., Cu, Cr, and Pb) or ERM (e.g., Cd, Ni, and Zn). This means that adverse effects for benthic organisms are possible or even highly probable. |
| Description: | The ScientificWorld Journal Volume 2012, Article ID 972839, 17 pages |
| URI: | http://dyuthi.cusat.ac.in/purl/4603 |
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| ToxicMetals Enr ... thwest Coast of India).pdf | (7.707Mb) |
| Abstract: | Asha M. R This thesis Entitled Toxicological effects of copper and mercury on the fish macerones gulio (hamiloton – buchanan).Chapter 1. In this chapter, a broad outline of heavy metal uptake, requirement of a suitable bio — monitoring organism, criteria for a standard test fish, and suitability of Macrones gulig for the toxicological study are given. Chapter 2. This chapter deals with the lethal toxicity bioassays to find the 96 hr LC 50 of copper and mercury for the fish Macrones gglig. The experimental results indicated that of the two metals tested, copper was more toxic than mercury.Chapter 3. The effect of copper and mercury on the haemoglobin, haematocrit, erythrocyte count, MCV, MCH and MCHC was studied.Chapter 4. The glycogen and protein contents of liver and muscle after exposure to copper and mercury were studied. There was a significant decrease of glycogen in the liver and muscle of metal treated fishes.Chapter 5. The histopathological changes of the tissues like liver, kidney and gill after exposure to copper and mercury were studied. |
| Description: | School of Marine Sciences, Department of Marinebiology, Microbiology and Biochemistry, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3035 |
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| Dyuthi-T1009.pdf | (3.102Mb) |
| URI: | http://dyuthi.cusat.ac.in/xmlui/purl/1898 |
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| Dyuthi-T0322.pdf | (9.305Mb) |
| Abstract: | The title of the study is ''Toxicology Literature: An Informetric Analysis".In the field of Toxicology, the interdisciplinary research resulted in 'information fragmentation' of the basic subject to environmental, medical and economic toxicology. The interest in collaborative research resulted in the transdisciplinary growth of Toxicology which ultimately resulted in the scatter of literature.For the purpose of present study Toxicology is defined as the physical and chemical aspects of all poisons affecting environmental, economical and medical aspects of human life. Informetrics is "the use and development of a variety of measures to study and analyse several properties of information in general and documents in particular."The present study fled light on the main fields of Toxicology research as well as the important primary journals through which the results are being published. The authorshippattern, subject-wise scatter, country-wise, language-wise and growth pattern, self-citation, bibliographic coupling of the journals were studied. The study will be of great use in forrnulatinq the acquisition policy of documents in a library. The present study is useful in identifying obsolate journals so that they can be discarded from the collection |
| Description: | Department of Computer Science, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3143 |
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| Dyuthi-T1117.pdf | (5.503Mb) |
| Abstract: | In this thesis T-policy is implemented to the inventory system with random lead time and also repair in the reliability of k-out-of-n system. Inventory system may be considered as the system of keeping records of the amounts of commodities in stock. Reliability is defined as the ability of an entity to perform a required function under given conditions for a given time interval. It is measured by the probability that an entity E can perform a required function under given conditions for the time interval. In this thesis considered k-out-of-n system with repair and two modes of service under T-policy. In this case first server is available always and second server is activated on elapse of T time units. The lead time is exponentially distributed with parameter and T is exponentially distributed with parameter from the epoch at which it was inactivated after completion of repair of all failed units in the previous cycle, or the moment n-k failed units accumulate. The repaired units are assumed to be as good as new. In this study , three different situations, ie; cold system, warm system and hot system. A k-out-of-n system is called cold, warm or hot according as the functional units do not fail, fail at a lower rate or fail at the same rate when system is shown as that when it is up. |
| URI: | http://dyuthi.cusat.ac.in/purl/41 |
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| Dyuthi-T0308.pdf | (3.217Mb) |
| Abstract: | In this note,the (t) properties of five class are studied. We proved that the classes of cographs and clique perfect graphs without isolated vertices satisfy the (2) property and the (3) property, but do not satisfy the (t) property for tis greater than equal to 4. The (t) properties of the planar graphs and the perfect graphss are also studied . we obtain a necessary and suffieient conditions for the trestled graph of index K to satisfy the (2) property |
| URI: | http://dyuthi.cusat.ac.in/purl/1533 |
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| The (t) property of some classes of graphs.PDF | (3.911Mb) |
| Abstract: | This thesis Entitled Trace metal speciation in the cochin estuary.Natural waters provide a favourable environment for speciation studies because of the prevailing variable chemical matrix and the variety of metal forms which may exist there.An estuary is a mixing zone of riverine and oceanic waters with widely varying compositions where end members interact both physically and chemically. The trace element chemistry in the estuarine environment has been an area of considerable research in the past decades. The trace metal distribution in the Cochin estuary is considerably influenced by the tropical features of the location and by human activities. The lower Periyar river and the Cochin estuary have been particularly selected for this investigation in view of the impact of trace metals on the estuarine ecosystem as well as in attempt quantify the phenomenon of metal speciation in the waters of a tropical coastal plain waterbody. If the concentration in the water media is very low, then, many of the fractions that could be estimated by speciation schemes for metals will fall below the detection limits, a factor which is undesirable.The study would also delineate the features of metal speciation which modify the chemical regime of ionic elements that traverse natural boundaries in aquatic environments, especally in those tropical areas prone to multivariate geographical settings. |
| Description: | Chemical Oceanography Division, School of Marine Sciences, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3117 |
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| Dyuthi-T1091.pdf | (4.663Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/1850 |
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| Dyuthi-T0320.pdf | (8.306Mb) |
| Abstract: | There are various studies conducted on transformational leadership and learning organization. The term gets more importance in current scenario as the technological advancement and many other factors made organization unsustainable without learning culture. The objective of this study was to identify relationship between transformational leadership and learning organizations. The study was conducted in 27 organizations inside Kerala and the tools used for the study are Multifactor leadership questionnaire (MLQ) 21 items by Bernad M Bass and B J Avolio and the Dimensions of learning organizations questionnaire (DLOQ) 43 items by Watkins and Marsick. The study has used confirmatory factor analysis, one way ANOVA, Pearson correlation analysis and Canonical discriminant function analysis for deriving the results. The result of this research proves that, there is a significant relationship between transformational leadership and learning organization. There is a significant positive impact of the factors of Transformational leadership i.e. idealized influence, inspirational motivation, intellectual stimulation, individual consideration, contingent reward, management by exception and laissez faire leadership in discriminating high, medium and low learning organization. |
| URI: | http://dyuthi.cusat.ac.in/purl/5261 |
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| Dyuthi T-2297.pdf | (2.291Mb) |
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