| Abstract: | The present work derives motivation from the so called surface/interfacial magnetism in core shell structures and commercial samples of Fe3O4 and c Fe2O3 with sizes ranging from 20 to 30 nm were coated with polyaniline using plasma polymerization and studied. The High Resolution Transmission Electron Microscopy images indicate a core shell structure after polyaniline coating and exhibited an increase in saturation magnetization by 2 emu/g. For confirmation, plasma polymerization was performed on maghemite nanoparticles which also exhibited an increase in saturation magnetization. This enhanced magnetization is rather surprising and the reason is found to be an interfacial phenomenon resulting from a contact potential. |
| Description: | Appl. Phys. Lett. 103, 162414 (2013) |
| URI: | http://dyuthi.cusat.ac.in/purl/4422 |
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| Contact potenti ... plasma polymerization.pdf | (1.752Mb) |
| Abstract: | Retrieval of similar anatomical structures of brain MR images across patients would help the expert in diagnosis of diseases. In this paper, modified local binary pattern with ternary encoding called modified local ternary pattern (MOD-LTP) is introduced, which is more discriminant and less sensitive to noise in near-uniform regions, to locate slices belonging to the same level from the brain MR image database. The ternary encoding depends on a threshold, which is a user-specified one or calculated locally, based on the variance of the pixel intensities in each window. The variancebased local threshold makes the MOD-LTP more robust to noise and global illumination changes. The retrieval performance is shown to improve by taking region-based moment features of MODLTP and iteratively reweighting the moment features of MOD-LTP based on the user’s feedback. The average rank obtained using iterated and weighted moment features of MOD-LTP with a local variance-based threshold, is one to two times better than rotational invariant LBP (Unay, D., Ekin, A. and Jasinschi, R.S. (2010) Local structure-based region-of-interest retrieval in brain MR images. IEEE Trans. Inf. Technol. Biomed., 14, 897–903.) in retrieving the first 10 relevant images |
| Description: | The Computer Journal,bxu008 |
| URI: | http://dyuthi.cusat.ac.in/purl/4224 |
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| Content-Based I ... ith a Ternary Encoding.pdf | (2.206Mb) |
| Abstract: | Magnetic Resonance Imaging play a vital role in the decision-diagnosis process of brain MR images. For an accurate diagnosis of brain related problems, the experts mostly compares both T1 and T2 weighted images as the information presented in these two images are complementary. In this paper, rotational and translational invariant form of Local binary Pattern (LBP) with additional gray scale information is used to retrieve similar slices of T1 weighted images from T2 weighted images or vice versa. The incorporation of additional gray scale information on LBP can extract more local texture information. The accuracy of retrieval can be improved by extracting moment features of LBP and reweighting the features based on users’ feedback. Here retrieval is done in a single subject scenario where similar images of a particular subject at a particular level are retrieved, and multiple subjects scenario where relevant images at a particular level across the subjects are retrieved |
| Description: | International Journal of Electrical, Robotics, Electronics and Communications Engineering Vol:7 No:8, 2013 |
| URI: | http://dyuthi.cusat.ac.in/purl/4233 |
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| Content Based I ... ross Different Classes.pdf | (1.187Mb) |
| Abstract: | Content Based Image Retrieval is one of the prominent areas in Computer Vision and Image Processing. Recognition of handwritten characters has been a popular area of research for many years and still remains an open problem. The proposed system uses visual image queries for retrieving similar images from database of Malayalam handwritten characters. Local Binary Pattern (LBP) descriptors of the query images are extracted and those features are compared with the features of the images in database for retrieving desired characters. This system with local binary pattern gives excellent retrieval performance |
| Description: | Neural Computing and Applications Vol 21(7),pp 1757-1763 |
| URI: | http://dyuthi.cusat.ac.in/purl/4207 |
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| Content Based I ... Handwritten Characters.pdf | (547.1Kb) |
| Abstract: | This paper proposes a region based image retrieval system using the local colour and texture features of image sub regions. The regions of interest (ROI) are roughly identified by segmenting the image into fixed partitions, finding the edge map and applying morphological dilation. The colour and texture features of the ROIs are computed from the histograms of the quantized HSV colour space and Gray Level co- occurrence matrix (GLCM) respectively. Each ROI of the query image is compared with same number of ROIs of the target image that are arranged in the descending order of white pixel density in the regions, using Euclidean distance measure for similarity computation. Preliminary experimental results show that the proposed method provides better retrieving result than retrieval using some of the existing methods. |
| Description: | Journal of Image and Graphics, Volume 1, No.1, March, 2013 |
| URI: | http://dyuthi.cusat.ac.in/purl/3884 |
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| Content Based I ... ed Regions of Interest.pdf | (1.651Mb) |
| Abstract: | This paper presents a Robust Content Based Video Retrieval (CBVR) system. This system retrieves similar videos based on a local feature descriptor called SURF (Speeded Up Robust Feature). The higher dimensionality of SURF like feature descriptors causes huge storage consumption during indexing of video information. To achieve a dimensionality reduction on the SURF feature descriptor, this system employs a stochastic dimensionality reduction method and thus provides a model data for the videos. On retrieval, the model data of the test clip is classified to its similar videos using a minimum distance classifier. The performance of this system is evaluated using two different minimum distance classifiers during the retrieval stage. The experimental analyses performed on the system shows that the system has a retrieval performance of 78%. This system also analyses the performance efficiency of the low dimensional SURF descriptor. |
| Description: | 2013 Third International Conference on Advances in Computing and Communications |
| URI: | http://dyuthi.cusat.ac.in/purl/4316 |
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| Content Based V ... using SURF Descriptor.pdf | (334.0Kb) |
| Abstract: | The purpose of this study was to evaluate the content growth of institutional repositories (IR) in South India and analyse the type-wise growth of items available in these IRs and also discuss the traits and trends exposed by them. With the help of Registry of Open Access Repositories and Directory of Open Access Repositories (OpenDOAR), 39 repositories were located in south India. From these, Personal websites, the IRs that are currently not working and the repositories used for journal archiving were excluded. A total of 22 operational IRs at 21 institutions were identified for the study. Within a 15 month period, the data were collected from the 22 IRs twice for monitoring content growth. The content of nearly all IRs have grown over the 15 month period, and the overall content growth rate was 7.82 per cent. Journal articles were the important content type of IRs, while thesis and conference papers were the next common. Moreover, item monographs exhibited the highest growth rate. Other categories, conference proceedings, and conference papers also exhibited a high growth rate. The present study revealed that Indian repositories were actively engaged in data curation activities, depositing a wide variety of items in their respective IRs. Overall, South Indian repositories exhibited a slow growth rate and tended to become inactive. Most South Indian Universities had not constituted the IRs, which led to the dominance of English language material in these IRs. The study was conducted only in South Indian IRs. This is the first study in India, attempting to determine the type-wise growth of items in IRs. Emerald allows authors to deposit their AAM under the Creative Commons Attribution Non- commercial International Licence 4.0 (CC BY-NC 4.0). |
| URI: | http://dyuthi.cusat.ac.in/purl/5570 |
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| Shajitha IR- Report - GKMC- 2nd revision.odt | (105.1Kb) |
| Abstract: | L-Glutamine amidohydrolase (L-glutaminase, EC 3.5.1.2) is a therapeutically and industrially important enzyme. Because it is a potent antileukemic agent and a flavor-enhancing agent used in the food industry, many researchers have focused their attention on L-glutaminase. In this article, we report the continuous production of extracellular L-glutaminase by the marine fungus Beauveria bassiana BTMF S-10 in a packed-bed reactor. Parameters influencing bead production and performance under batch mode were optimized in the order-support (Na-alginate) concentration, concentration of CaCl2 for bead preparation, curing time of beads, spore inoculum concentration, activation time, initial pH of enzyme production medium, temperature of incubation, and retention time. Parameters optimized under batch mode for L-glutaminase production were incorporated into the continuous production studies. Beads with 12 × 108 spores/g of beads were activated in a solution of 1% glutamine in seawater for 15 h, and the activated beads were packed into a packed-bed reactor. Enzyme production medium (pH 9.0) was pumped through the bed, and the effluent was collected from the top of the column. The effect of flow rate of the medium, substrate concentration, aeration, and bed height on continuous production of L-glutaminase was studied. Production was monitored for 5 h in each case, and the volumetric productivity was calculated. Under the optimized conditions for continuous production, the reactor gave a volumetric productivity of 4.048 U/(mL·h), which indicates that continuous production of the enzyme by Ca-alginate-immobilizedspores is well suited for B. bassiana and results in a higher yield of enzyme within a shorter time. The results indicate the scope of utilizing immobilized B. bassiana for continuous commercial production of L-glutaminase |
| Description: | Applied Biochemistry and Biotechnology,Vol. 102–103, 2002 |
| URI: | http://dyuthi.cusat.ac.in/purl/4260 |
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| Continuous Prod ... in Packed-Bed Reactor.pdf | (89.19Kb) |
| Abstract: | A marine Pseudomonas sp BTMS-51, immobilized by Ca-alginate gel entrapment was used for the production of extracellular Lglutaminase under repeated batch process and continuous process employing a packed bed reactor (PBR). Immobilized cells could produce an average of 25 U/ml of enzyme over 20 cycles of repeated batch operation and did not show any decline in production upon reuse. The enzyme yield correlated well with the biomass content in the beads. Continuous production of the enzyme in PBR was studied at different substrate concentrations and dilution rates. In general, the volumetric productivity increased with increased dilution rate and substrate concentrations and the substrate conversion efficiency declined. The PBR operated under conditions giving maximal substrate conversion efficiency gave an average yield of 21.07 U/ml and an average productivity of 13.49 U/ml/h. The system could be operated for 120 h without any decline in productivity |
| Description: | Process Biochemistry 38 (2003) 1431 /1436 |
| URI: | http://dyuthi.cusat.ac.in/purl/4244 |
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| Continuous prod ... n a packed bed reactor.pdf | (208.7Kb) |
| Abstract: | HINDI |
| Description: | DEPARTMENT OF HINDI, CUSAT |
| URI: | http://dyuthi.cusat.ac.in/purl/4898 |
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| Dyuthi-T1993.pdf | (7.548Mb) |
| Abstract: | This thesis entitled “Contribution of size fractions of planktonic algae to primary organic productivity in the coastal waters of cochin,south west coast of india”. Marine ecosystems planktonic algae are the most important primary producers on wliich considerable attention is being given on account of their supreme status in the marine food chain.The study of primary production in the Indian Ocean started With DANA (I928-30),, John Murray t I933-34). Discovery ( I934) and Albatross (I947-48) expeditions which tried to evaluate productivity from nutrients and standing crop of phytoplankton .The bioproductivity of the marine environment is dependent on various primary producers. ranging in size from picoplankton to larger macro phytoplankton. The quantity and quality of various size fractions of planktonic algae at any locality depend mainly on the hydrographic conditions of the area .In the coastal waters of Cochin- south west coast of lndia. Planktonic algal community is composed mainly of the diatoms, the dinoflagellates, the blue-green algae and the silicoflagellates, the former two contributing the major flora and found distributed in the all size fractions. The maximum number of species of diatoms at station 1 and station 2 was found in the pre-monsoon season.. The size groups of planktonic algae greater than 53 um are dominated by filamentous- chain forming and colonial diatoms. The coastal waters of Cochin. planktonic algae less than 53 um in size contribute significantly to primary productivity and the biodiversity of the microflora, indicating the presence of rich fishery resources in the south west coast of india.The study of different size fractions of planktonic algae and their relative contribution to the primary organic production is a useful tool for the estimation of the quantity and quality of fisheries.A deeper investigation on the occurrence of these microalgae and proper identification of their species would be of immense help for the assessment of the specificity and magnitude of fishery resources. |
| Description: | School of Marine Science, Department of Marine biology, Microbiology and Biochemistry, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3038 |
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| Dyuthi-1012.pdf | (6.038Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/1285 |
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| Velayudhan K K 1983.PDF | (74.28Kb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5587 |
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| Dyuthi T-2628.pdf | (4.724Mb) |
| URI: | http://dyuthi.cusat.ac.in/xmlui/purl/1985 |
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| Dyuthi-T0385.pdf | (14.46Mb) |
| Abstract: | We show numerically that direct delayed optoelectronic feedback can suppress hysteresis and bistability in a directly modulated semiconductor laser. The simulation of a laser with feedback is performed for a considerable range of feedback strengths and delays and the corresponding values for the areas of the hysteresis loops are calculated. It is shown that the hysteresis loop completely vanishes for certain combinations of these parameters. The regimes for the disappearance of bistability are classified globally. Different dynamical states of the laser are characterized using bifurcation diagrams and time series plots. |
| URI: | http://dyuthi.cusat.ac.in/purl/2531 |
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| Dyuthi-P0106.pdf | (671.3Kb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5326 |
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| Dyuthi T-2362.pdf | (3.421Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5184 |
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| Dyuthi T-2219.pdf | (1.171Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5036 |
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| SR 51(11) 38-41 (1).pdf | (4.085Mb) |
| Abstract: | The concept of convex extendability is introduced to answer the problem of finding the smallest distance convex simple graph containing a given tree. A problem of similar type with respect to minimal path convexity is also discussed. |
| URI: | http://dyuthi.cusat.ac.in/purl/2861 |
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| Dyuthi-P00404.pdf | (88.02Kb) |
| Abstract: | Due to the advancement in mobile devices and wireless networks mobile cloud computing, which combines mobile computing and cloud computing has gained momentum since 2009. The characteristics of mobile devices and wireless network makes the implementation of mobile cloud computing more complicated than for fixed clouds. This section lists some of the major issues in Mobile Cloud Computing. One of the key issues in mobile cloud computing is the end to end delay in servicing a request. Data caching is one of the techniques widely used in wired and wireless networks to improve data access efficiency. In this paper we explore the possibility of a cooperative caching approach to enhance data access efficiency in mobile cloud computing. The proposed approach is based on cloudlets, one of the architecture designed for mobile cloud computing. |
| Description: | Global Journal of Computer Science and Technology Network, Web & Security Volume 13 Issue 8 Version 1.0 Year 2013 |
| URI: | http://dyuthi.cusat.ac.in/purl/3899 |
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| Cooperative Cac ... Mobile Cloud Computing.pdf | (650.6Kb) |
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