Development and Investigations of Mobile Antennas for less Radiation Hazards

Antennas, the key element in wireless communication devices had undergone amazing developments especially in the direction of compactness and safety aspects. In the last two decades, the use of the cellular phones has become the most popular mode of communication across the globe. At the same time, the concerns about the radiation effects have increased in the general public. The main concern of this thesis is to develop a mobile antenna which gives reduced RF interference to the user. The reduction of the power absorbed by the user can tremendously avoid any possible health hazards. The radiation characteristic of a monopole antenna is modified with good radiation characteristics suitable for a mobile handset. The modification is implemented by using different resonating structures which provides reduced radiation along one direction. The direction of less radiation can be changed by modifying the planar antenna structure to a ground folded antenna. This modified structure with excellent radiation characteristic is suitable for modern wireless handheld devices with less user RF interference. Specific Absorption Rate (SAR) is an important parameter for mobile handset. The SAR is estimated for the newly developed antenna for different conditions and discussed in this thesis.

Technological Change and the Development of the Primary Fishing Industry of Kerala - A Study of Limited Growth

Induction of growth in the primary marine fishing industry of Kerala is a sine gua Qgn for improving the economy of the fishermen, the state's domestic product as well as earning more foreign exchange for the country. The State Administration has been trying to instil growth into the industry eversince the output of the industry showed marked sign of decline (particularly after 1975). Significantly, it has attempted to strengthen the traditional sector, (which is considered to be the crucial sector of the primary marine fishing industry of the state) by introducing intermediate technology and by revamping the organisational structure of the industry. But it appears that the production system in the primary marine fishing industry of Kerala has been severely constrained by the existing technology, organisation of production and marketing institutions. Regeneration of growth in the industry calls forth an understanding of the 'process' of growth in the industry and the need to réorganise it with new technology, and new organisations. The present study is an attempt to unraval the process of growth in the primary marine fishing industry of Kerala since 1951

Studies on a syntax based approach for translation between structurally different languages and the development of a prototype for Malayalam to English translation

This thesis summarizes the results on the studies on a syntax based approach for translation between Malayalam, one of Dravidian languages and English and also on the development of the major modules in building a prototype machine translation system from Malayalam to English. The development of the system is a pioneering effort in Malayalam language unattempted by previous researchers. The computational models chosen for the system is first of its kind for Malayalam language. An in depth study has been carried out in the design of the computational models and data structures needed for different modules: morphological analyzer , a parser, a syntactic structure transfer module and target language sentence generator required for the prototype system. The generation of list of part of speech tags, chunk tags and the hierarchical dependencies among the chunks required for the translation process also has been done. In the development process, the major goals are: (a) accuracy of translation (b) speed and (c) space. Accuracy-wise, smart tools for handling transfer grammar and translation standards including equivalent words, expressions, phrases and styles in the target language are to be developed. The grammar should be optimized with a view to obtaining a single correct parse and hence a single translated output. Speed-wise, innovative use of corpus analysis, efficient parsing algorithm, design of efficient Data Structure and run-time frequency-based rearrangement of the grammar which substantially reduces the parsing and generation time are required. The space requirement also has to be minimised

Environmentally-Efficient Development Management System for Greater Kochi in Kerala State”

The base concept from which the entire research problem emerged is as follows: Lack of spatial planning and effective development management system lead to urban sprawl with non-optimal density of population to support urban infrastructure on the one side causing a lesser quality of life in urban areas. On the other side it causes loss of productivity of natural ecosystems and agricultural areas due to disturbance to the ecosystems. Planned compact high density development with compatible mixed land use can go a long way in achieving environmental efficiency of development management system.

Level Of Women Participation In Rural Development - A Comparative Study Of Governmental And Non-Governmental Organisations In Kerala

The study is intended to estimate the existing rate of participation of women beneficiaries in the development programmes of different organisations in Kerala. It would enable one to understand whether participation is at the satisfactory level or not. Given the rate of participation, the major thrust of the analysis is on the impact of governmental and non-governmental organisations on the rate of participation. This is undertaken under the assumption that NGOs, due to their proximity to people and their needs, ensure better participation rates. Besides the organisational differences, the other major determinants of women participation such as their socio-economic characteristics, psychological make up, the nature of the programme etc. are also highlighted. 0 Since the ascribed status of women in society is inferior, the role of organisers, development personnel and local leaders is also pointed out. Thus the basic objective of the study is women participation and its determinants in the development programmes

Development and Deployment of Wireless Sensor Network in Paddy Fields of Kuttanad

The evolution of wireless sensor network technology has enabled us to develop advanced systems for real time monitoring. In the present scenario wireless sensor networks are increasingly being used for precision agriculture. The advantages of using wireless sensor networks in agriculture are distributed data collection and monitoring, monitor and control of climate, irrigation and nutrient supply. Hence decreasing the cost of production and increasing the efficiency of production. This paper describes the development and deployment of wireless sensor network for crop monitoring in the paddy fields of Kuttanad, a region of Kerala, the southern state of India.

E-Resources in the Engineering College Libraries of Kerala: Problems towards Sustainable Collection Development

Electronic resources have become a vital part of an academic library especially in universities and higher education institutions. The availability of electronic resources and the acceptance of the fonnat among the academics are rising day by day. As far as engineering students are concerned, they are much techno-savy and are more used to electronic resources. So it has become necessary for the libraries of engineering institutions to subscribe and provide access to electronic resources to satisfy its user community. Many studies have identified that academics are much preferring online journals and databases than their print counter-parts

Development of p-type transparent semiconducting oxides for thin film transistor applications

Semiconductor physics has developed significantly in the field of re- search and industry in the past few decades due to it’s numerous practical applications. One of the relevant fields of current interest in material science is the fundamental aspects and applications of semi- conducting transparent thin films. Transparent conductors show the properties of transparency and conductivity simultaneously. As far as the band structure is concerned, the combination of the these two properties in the same material is contradictory. Generally a trans- parent material is an insulator having completely filled valence and empty conduction bands. Metallic conductivity come out when the Fermi level lies within a band with a large density of states to provide high carrier concentration. Effective transparent conductors must nec- essarily represent a compromise between a better transmission within the visible spectral range and a controlled but useful electrical con- ductivity [1–6]. Generally oxides like In2O3, SnO2, ZnO, CdO etc, show such a combination. These materials without any doping are insulators with optical band gap of about 3 eV. To become a trans- parent conductor, these materials must be degenerately doped to lift the Fermi level up into the conduction band. Degenerate doping pro- vides high mobility of extra carriers and low optical absorption. The increase in conductivity involves an increase in either carrier concen- tration or mobility. Increase in carrier concentration will enhance the absorption in the visible region while increase in mobility has no re- verse effect on optical properties. Therefore the focus of research for new transparent conducting oxide (TCO) materials is on developing materials with higher carrier mobilities.

Development of Techniques for the Automatic Extraction and Grade Detection of Glioma Tumors from Conventional Brain Magnetic Resonant Images

Cerebral glioma is the most prevalent primary brain tumor, which are classified broadly into low and high grades according to the degree of malignancy. High grade gliomas are highly malignant which possess a poor prognosis, and the patients survive less than eighteen months after diagnosis. Low grade gliomas are slow growing, least malignant and has better response to therapy. To date, histological grading is used as the standard technique for diagnosis, treatment planning and survival prediction. The main objective of this thesis is to propose novel methods for automatic extraction of low and high grade glioma and other brain tissues, grade detection techniques for glioma using conventional magnetic resonance imaging (MRI) modalities and 3D modelling of glioma from segmented tumor slices in order to assess the growth rate of tumors. Two new methods are developed for extracting tumor regions, of which the second method, named as Adaptive Gray level Algebraic set Segmentation Algorithm (AGASA) can also extract white matter and grey matter from T1 FLAIR an T2 weighted images. The methods were validated with manual Ground truth images, which showed promising results. The developed methods were compared with widely used Fuzzy c-means clustering technique and the robustness of the algorithm with respect to noise is also checked for different noise levels. Image texture can provide significant information on the (ab)normality of tissue, and this thesis expands this idea to tumour texture grading and detection. Based on the thresholds of discriminant first order and gray level cooccurrence matrix based second order statistical features three feature sets were formulated and a decision system was developed for grade detection of glioma from conventional T2 weighted MRI modality.The quantitative performance analysis using ROC curve showed 99.03% accuracy for distinguishing between advanced (aggressive) and early stage (non-aggressive) malignant glioma. The developed brain texture analysis techniques can improve the physician’s ability to detect and analyse pathologies leading to a more reliable diagnosis and treatment of disease. The segmented tumors were also used for volumetric modelling of tumors which can provide an idea of the growth rate of tumor; this can be used for assessing response to therapy and patient prognosis.

Development of a Fully Automated Image Analysis Method for High Density cDNA and array CGH Microarray Based Genomic Studies

In this thesis, different techniques for image analysis of high density microarrays have been investigated. Most of the existing image analysis techniques require prior knowledge of image specific parameters and direct user intervention for microarray image quantification. The objective of this research work was to develop of a fully automated image analysis method capable of accurately quantifying the intensity information from high density microarrays images. The method should be robust against noise and contaminations that commonly occur in different stages of microarray development.

“Design and Development of Coplanar Strip Fed Planar Antennas”

With the recent progress and rapid increase in the field of communication, the designs of antennas for small mobile terminals with enhanced radiation characteristics are acquiring great importance. Compactness, efficiency, high data rate capacity etc. are the major criteria for the new generation antennas. The challenging task of the microwave scientists and engineers is to design a compact printed radiating structure having broadband behavior along with good efficiency and enhanced gain. Printed antenna technology has received popularity among antenna scientists after the introduction of planar transmission lines in mid-seventies. When we view the antenna through a transmission line concept, the mechanism behind any electromagnetic radiator is quite simple and interesting. Any electromagnetic system with a discontinuity is radiating electromagnetic energy. The size, shape and orientation of the discontinuities control the radiation characteristics of the system such as radiation pattern, gain, polarization etc. It can be either resonant or non-resonant. This thesis deals with antennas that are developed from a class of transmission lines known as coplanar strip-CPS, a planar analogy of parallel pair transmission line. The specialty of CPS is its symmetric structure compared to other transmission lines, which makes the antenna structures developed from CPS quite simple for design and fabrication. The structural modifications on either metallic strip of CPS results in different antennas. The first part of the thesis discusses a single band and dual band design derived from open ended slot lines which are very much suitable for 2.4 and 5.2 GHz WLAN applications. The second section of the study is vectored into the development of enhanced gain dipoles. A single band dipole and a wide band enhanced gain dipole suitable for 5.2/5.8 GHZ band and imaging applications are developed and discussed. Last part of the thesis discusses the development of directional UWBs. Three different types of ultra-compact UWBs are developed and almost all the frequency domain and time domain analysis of the structures are discussed.

Development of a cell culture system from the ovarian tissue of African catfish Clarias gariepinus

A growth medium with Leibovitz-15 L-15.as the base, supplemented with foetal bovine serum 10% vrv., fish muscle extract 10% vrv., prawn muscle extract 10% vrv., lectin concanavalin A. 0.02 mg mly1., lipopolysaccharide 0.02 mg mly1., glucose D 0.2 mg mly1., ovary extract 0.5% vrv.and prawn haemolymph 0.5%. has been formulated with 354"10 mOsm for the development and maintenance of a cell culture system from the ovarian tissue of African catfish, Clarias gariepinus. For its subculturing, a cell dissociationrextracting solution, composed of equal portions of trypsin phosphate versene glucose TPVG. containing 0.0125% wrv.trypsin and 25% vrv.non-enzymatic cell dissociation solution 1 and 2, has also been developed with which the cell culture can be passaged 15 times after which they cease to multiply and consequently perish. The cell cultures can be maintained for 12–15 days without fluid change between the passages. This is the first report of a cell culture system from the ovarian tissues of African catfish

Development of nitrifying bacterial consortia for immobilizing in nitrifying bioreactors designed for penaeid and non-penaeid larval rearing systems in the tropics

Two ammonia oxidizing (AMOPCU-1 and AMONPCU-1) and two nitrite oxidizing (NIOPCU-1 and NIONPCU-1) consortia for activating nitrifying bioreactors and thereby establishing nitrification in penaeid and non-penaeid hatchery systems were developed by enrichment. For further amplification of the consortia a simple medium having seawater (either salinity 30 ‰ or 15 ‰) as base, supplemented with NH4+-N/NO2--N and PO4- and pH adjusted to 8 was identified. During the amplification in a fermentor the consortia exhibited excessive wall growth and diminished their yield coefficient posing difficulty in harvesting the cells completely. The consortia consisted of both Gram negative and Gram-positive bacterial cells embedded in a mucilaginous matrix of glycocalyx - like material presumably composed of polysaccharides. The consortia besides being useful in activating nitrifying bioreactors developed for shrimp/prawn hatchery systems can also be used as bioaugmentors in the bioremediation of ammonia and nitrite toxicity in aquaculture systems.

A novel medium for the development of in vitro cell culture system from Penaeus monodon

Lack of a valid shrimp cell line has been hampering the progress of research on shrimp viruses. One of the reasons identified was the absence of an appropriate medium which would satisfy the requirements of the cells in vitro. We report the first attempt to formulate an exclusive shrimp cell culture medium (SCCM) based on the haemolymph components of Penaeus monodon prepared in isosmotic seawater having 27 % salinity. The SCCM is composed of 22 amino acids, 4 sugars, 6 vitamins, cholesterol, FBS, phenol red, three antibiotics, potassium dihydrogen phosphate and di-sodium hydrogen phosphate at pH 6.8–7.2. Osmolality was adjusted to 720 ± 10 mOsm kg-1 and temperature of incubation was 25 8C. The most appropriate composition was finally selected based on the extent of attachment of cells and their proliferation by visual observation. Metabolic activity of cultured cells was measured by MTT assay and compared with that in L-15 (29), modified L-15 and Grace’s insect medium, and found better performance in SCCM especially for lymphoid cells with 107 % increase in activity and 85 ± 9 days of longevity. The cells from ovary and lymphoid organs were passaged twice using the newly designed shrimp cell dissociation ‘‘cocktail’’.

Development Of A Pos Tagger For Malayalam-An Experience

A Parts of Speech tagger for Malayalam which uses a stochastic approach has been proposed. The tagger makes use of word frequencies and bigram statistics from a corpus. The morphological analyzer is used to generate a tagged corpus due to the unavailability of an annotated corpus in Malayalam. Although the experiments have been performed on a very small corpus, the results have shown that the statistical approach works well with a highly agglutinative language like Malayalam