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Influence of radiative transfer on Rayleigh-Benard-Marangoni canvection in a couple-stress fluid saturated porous medium
The problem of Rayleigh-Benard-Marangoni convection in a couple-stress fluid saturated porous medium with thermal radiation is studied within the framework of linear stability analysis. Only infinitesimal disturbances are considered. The linear stability analysis is based on the normal mode technique. The Darcy law is used to model the momentum equation. The fluid between the boundaries absorbs and emits thermal radiation. The boundaries are treated as black bodies. The absorption coefficient of the fluid is assumed to be the same at all wavelengths and to be independent of the physical state. The principle of exchange of stabilities is valid and the existence of oscillatory instability is ruled out. The expression for the stationary Darcy-Rayleigh number is obtained as a function of the governing parameters, viz., the wave number, the couple-stress parameter, the conduction-radiation parameter, the absorptivity parameter, the Marangoni number and the Biot number. The Galerkin method is used to determine the eigenvalues. The effect of various parameters on the stability of the fluid layer is discussed through figures and tables. -
Effect of magnetic field on the onset of Rayleigh-Benard convection in a micropolar fluid with internal heat generation
The effects of through flow, internal heat generation and magnetic field on the onset of Rayleigh-Benard convection in electrically conducting Micropolar fluid are studied using the Galerkin technique. The eigenvalue is obtained for rigid-free velocity boundary combinations with isothermal and adiabatic on the spin-vanishing boundaries. A linear stability analysis is performed. The influence of various parameters on the onset of convection has been analyzed. The microrotation is assumed to vanish at the boundaries. A linear stability analysis is performed. The influence of various parameters on the onset of convection has been analyzed and their comparative influence on onset is discussed. The problem suggests an elegant method of external control of internal convection. -
Chemical reaction induced Rayleigh-Benard convection in a densely packed porous medium saturated with a couple-stress fluid
The problem of Rayleigh-Benard convection in a couple-stress fluid saturated densely packed porous medium with chemical reaction is studied within the framework of linear stability analysis. Only infinitesimal disturbances are considered. The linear stability analysis is based on the normal mode technique. The Darcy law is used to model the momentum equation. Closed form solution for the basic quiescent state is first obtained. The principle of exchange of stabilities is valid and the existence of oscillatory instability is ruled out. The expression for the stationary media-Darcy-Rayleigh number is obtained as a function of the governing parameters, viz., the wave number, the couple-stress parameter and the Frank-Kamenetskii number. The Galerkin method is used to determine the eigenvalues. The effect of various parameters on the stability of the fluid layer is discussed through figures. -
Effect of radiative transfer on Rayleigh-Benard convection in a couple- stress fluid
The problem of Rayleigh-Benard convection in a couple-stress fluid with thermal radiation is studied within the framework of linear stability analysis. Only infinitesimal disturbances are considered. The linear stability analysis is based on the normal mode technique. The fluid between the boundaries absorbs and emits thermal radiation. The boundaries are treated as black bodies. The absorption coefficient of the fluid is assumed to be the same at all wavelengths and to be independent of the physical state. The principle of exchange of stabilities is valid and the existence of oscillatory instability is ruled out. The expression for the stationary Rayleigh number is obtained as a function of the governing parameters, viz., the wave number, the couple-stress parameter, the conduction-radiation parameter and the absorptivity parameter. The Galerkin method is used to determine the eigenvalues. The effect of various parameters on the stability of the fluid layer is discussed through figures and tables. -
Chemically driven Rayleigh-Benard convection in a sparsely distributed porous medium saturated with a couple-stress fluid
The problem of Rayleigh-Benard convection in a couple-stress fluid saturated sparsely distributed porous medium with chemical reaction is studied within the framework of linear stability analysis. Only infinitesimal disturbances are considered. The linear stability analysis is based on the normal mode technique. The Darcy-Brinkman law is used to model the momentum equation. Closed form solution for the basic quiescent state is first obtained. The principle of exchange of stabilities is valid and the existence of oscillatory instability is ruled out. The expression for the stationary media-Rayleigh number is obtained as a function of the governing parameters, viz., the wave number, the couple-stress parameter, the Frank-Kamenetskii number, the porous parameter and the Brinkman number. The Galerkin method is used to determine the eigenvalues. The effect of various parameters on the stability of the fluid layer is discussed through figures. -
Effect of temperature modulation on Rayleigh-Benard convection in a rotating layer of a ferromagnetic fluid
The stability of a rotating horizontal layer of ferromagnetic fluid heated from below is examined when, in addition to a steady temperature difference between the walls of the layer, a time-dependent sinusoidal perturbation is applied to the wall temperatures. Only infinitesimal disturbances are considered. The effects of the oscillating temperature field are treated by a perturbation expansion in powers of the amplitude of the applied field. The onset criterion is derived when the condition for the principle of exchange of stabilities is valid. The shift in the critical Rayleigh number is calculated as a function of the frequency of modulation, magnetic parameters, Taylor number and Prandtl number. The effect of various parameters is found to be significant for moderate values of the frequency of modulation. It is shown that, when the thermal excitation is symmetric, supercritical motion is more pronounced for low Prandtl number ferro fluids. Further, for the case in which only the bottom wall temperature is modulated, the effect of rotation is to stabilize the system at low frequencies and the opposite is true for moderately large frequencies. The problem throws light on external means of controlling convection in ferromagnetic fluid applications. -
Rayleigh-Benard-Marangoni electro-convection in a dielectic micropolar fluid /
The linear analysis of Rayleigh-B??nard-Marangoni convection in dielectric micropolar fluid is studied using the Galerkin technique. In the case of Rayleigh ?? B??nard convection, the eigenvalue is obtained for free - free, rigid ?? free and rigid ?? rigid velocity boundary combinations with isothermal and adiabatic on the spin-vanishing boundaries. A linear stability analysis is performed. The influence of various parameters on the onset of convection has been analyzed. In the case of Marangoni and Rayleigh-B??nard-Marangoni convection the eigenvalues are obtained for an upper free / adiabatic and lower rigid / isothermal boundaries. The microrotation is assumed to vanish at the boundaries. The influence of various parameters on the onset of convection has been analyzed and their comparative influence on onset is discussed. -
Changing and unchanging domination parameters /
Graph Theory is a delightful playground for the exploration of proof techniques in discrete mathematics, and its results have applications in many areas of computing, social, and natural sciences. How can we lay cable at minimum cost to make every telephone reachable from every other? What is the fastest route from the national capital to each state capital? How can n jobs be filled by n people with maximum total utility? What is the maximum flow per unit time from source to sink in a network of pipes? How many layers does a computer chip need so that wires in the same layer don’t cross? How can the season of a sports league be scheduled into the minimum number of weeks? -
Achievement of children in academics: An exploration into parental philosophies /
The current study is an exploration into parental philosophies behind their involvement in the academic lives of their children. 14 pairs of parents and children were interviewed and the data gathered was analyzed using thematic analysis. The role that parents play in shaping the academic and vocational choices of their children was analyzed. The framework of this study included childrens perspectives on parental involvement in their academic lives as well. This was to gain insight into childrens point of view on how similar or different their thinking was from their parents on matters such as education, hobbies, career goals, academic expectations. -
The family strengths of the Lambhanis of Bellary district /
The study titled The Family Strengths of the Lambhanis of Bellary District aimed at identifying and exploring Family Strengths of the Lambhanis their perpetuation. The study was based on the Family Strengths Model using an Interpretivistic Research Philosophy and a Grounded Theory Research Paradigm within a Qualitative Framework. The sample of the study was taken through a key informant. The participants were from Dasarhalli Thanda, Bellary District, Karnataka. They were all adults both men and women. Three Focus Groups were conducted and the interviews were unstructured, data was collected until Data Saturation was reached. The data was recorded/taped, translated and transcripts written. The data gathered was then coded based on the Grounded Theory Method proposed by Strauss and Corbin (1998). -
A study on the self-esteem and social relations of adolescents with learning disability /
According to World Health Organization Learning disability is a state of arrested or incomplete development of mind. The most common learning disabilities are Dyslexia, Dyscalculia Dysgraphia, Auditory and Visual Processing Disorders and Nonverbal Learning Disabilities. Adolescents with learning difficulty have trouble expressing their feelings, calming themselves down, and reading non-verbal cues which can lead to difficulty in the classroom and with their peers. In India approximately 13 to 14 per cent of all school children suffer from learning disorders (Sadaket 2009). The social relationships of the adolescents with learning disability have a positive influence on their self esteem. It helps them to maintain a constructive relationship with their peers, teachers and parents. The study was focused to know the relationship of self esteem and social relation in adolescents with learning disability. The study was conducted among all the Adolescents with Learning Disability, in an alternative school in Bangalore. The size of the sample was 50 which include both genders and the sampling design was purposive sampling. -
A study on the family environment of persons with thalassemia major
The objective of the study was to assess the family environment of persons with thalassemia major disorder. The clinical profile of the persons with thalassemia, the family awareness about the disorder and the social, financial, emotional and the couple relationship aspects due to thalassemia were also studied. The parents of the persons with thalassemia major were included in the study. Interviews were carried out with each of the subjects using a standard questionnaire to assess the family environment. The other aspects were studied using a semi structured questionnaire. The results show that 42 percent has a family income of less than 5000 Rupees per month. There is no mutual emotional support among 54 percent of the couples. 66 percent of the parents are not involved in any social activities. 14 percent of the parents feel burden and another 14 percent feel burnout and 38 percent are anxious about the sick child. The relationship with the non thalassemic child in the family is affected among 55 percent of the parents. 86 percent of the parents are aware about the need of iron chelation and the genetic nature of thalassemia. Family environment is significantly affected by the duration of the illness, treatment cost, number of thalassemia persons in the family, lack of awareness on the genetic nature on thalassemia. Hospital admissions restrict the recreational activities and also lead to lose of control in the family. Organization in the family is significantly affected where there is more number of persons with thalassemia. The subjects assessed expressed varying concerns about the family relationships, life long illness of the child and other psycho social issues. They feel that their competitiveness, career development, financial needs and relationships with their spouse and with their normal child are hampered by the illness of the child. It establishes that various psycho social interventions are imperative for such families. -
The correlation between work locus of control and occupational stress among team leaders working in it companies in Bangalore
Job related stress is one of the highest health risks influencing employees, regardless of the size of the organization or the work sector. Most of the researchers view stress as an interaction between the person and some environmental event or stressor. Job stressors are defined as job demands, constraints, and or opportunities and job related events or situations that might affect the individuals feelings of stress. The fact that employee stress is an increasing problem in almost all organizations has indeed been the driving force for a variety of researches on occupational stress. The literature on occupational stress recognizes its inevitability in many jobs where pressures of work begin to build up and cause adverse strain on the emotion of employees, their thought process and their physical condition. Stress vulnerability has also been major focus to determine how stress effects differently across similar jobs. During the 1980s, personality[Type A/ Type B, locus of control] was found to be related to job stressors[ work load, role conflict, lack of autonomy], job strains[ job dissatisfaction, anxiety, health complaints]. The research aims to investigate the relationship between Work locus of control and occupational stress of team leaders working in IT companies in Bangalore. The purpose of research is to study whether the team leaders have an internal or external locus of control, which in turn determines how they perceive situations and life events, and how stressed they are due to this. It was hypothesized that the higher the internal locus of control of the team leader, the lower level of occupational stress they experience and the higher the external locus of control of the team leader, the higher the level of occupational stress. A sample of 100 team leaders working in three different IT companies were examined by administering the Occupational stress index by AP Singh and AK Srivastava and Work locus of control scale by Paul E Spector. The extent of work stress was examined on its twelve sub-scales, i.e. role overload, role ambiguity, role conflict, unreasonable group and political pressure, responsibility for persons, under participation, powerlessness, poor peer relations, intrinsic impoverishment, low status, strenuous working condition and unprofitability of Occupational stress index. A structured questionnaire was designed to gather information on the socio demographic profile of the respondents. The statistical analysis was done using SPSS. The level of significance was fixed at 0.005(p<0.005). Correlational analysis reveals that team leaders with external locus of control score high on all twelve sub scales of occupational stress and team leaders with internal locus of control have low scores on all twelve sub scales of occupational stress i.e. role overload, role ambiguity, role conflict, unreasonable group and political pressure, responsibility for persons, under participation, powerlessness, poor peer relations, intrinsic impoverishment, low status, strenuous working condition and unprofitability. There is a significant difference with regard to occupational stress between team leaders with external locus of control and team leaders with internal locus of control. The correlation between occupational stress and external control was found to be positive and significant as predicted (p=<0.001). The correlation between occupational stress and internal control was found to be positive and significant as predicted (p=<0.001). -
A study on the voting patterns and the impact of Kormangala smart votescampaign in ward 151, Kormangala , Bangalore /
The study on the voting patterns and the impact of Koramangala Smart Votes campaign, in Koramangala Ward 151, Bangalore. This aims at studying the voting pattern of the residents of Koramangala from two wards 151 and 147. Koramangala Smart Votes, a campaign which was conducted by the Smart Vote members to help the residents vote and vote for a right candidate by distributing profiles and organizing debates connecting the residents and the contesting candidates. The impact of this campaign has been assessed with the help of Lok Sabha and BBMP elections 2010 and the voter turn out in wards 151 and 147. To measure the impact, the researcher has done a quantitative and comparative study among the residents of wards 151 and 147 with a sample size of 60 respondents from each ward. It could be observed that Education helps to create better democratic environment and the Koramangala Smart Votes campaign was fairly successful in getting the residents to vote for the BBMP elections 2010. -
Development of efficient biometric recognition algorithms based on fingerprint and face /
The reliable verification systems are required to verify and confirm the identity of an individual requesting their service. Secure access to the buildings, laptops, cellular phones, ATM etc. is an example of such applications. In the absence of robust verification systems, these systems are vulnerable to the wiles of an impostor. The traditional ways of authentications are passwords (knowledge ?? based security) and the ID Cards (token ?? based security). These methods can be easily breached due to the chance of stolen, lost or forget. The development and progress of biometrics technology, the fear of stolen, lost or forget can be eliminated. Biometrics refers to the automatic identification (or verification) of an individual (or a claimed identity) by using certain physiological or behavioral traits associated with the person. The biometrics identifies the person based on features vector derived from physiological or behavioural characteristics such as uniqueness, permanence, accessibility, collectability with minimum cost. The physiological biometrics are Fingerprint, Hand Scan, Iris Scan, Facial Scan and Retina Scan etc., and behavioural biometric are Voice, Keystroke, Gait, Signature etc., The physiological biometrics measures the specific part of the structure or shape of a portion of a subjects body. But the behavioural biometric are more concerned with mood and environment. Chapter one presents the introduction to biometrics and its various traits. Further description like structure of the biometric system, different approaches are discussed. Also the design issues in biometric system such as universality, collectability, distinctiveness, permanence, acceptability, uniqueness, performance, circumvention etc., are discussed. Chapter two gives a detailed survey of biometric techniques. It includes the literature survey of fingerprint and face biometric traits and various approaches. In Chapter three, the algorithm of Fingerprint Verification based on Dual Tree Complex Wavelet Transformation (DTCWT) is proposed. The original fingerprint is cropped and resized to apply the DTCWT. The features of Fingerprint are obtained by applying different levels of DTCWT. Performance analysis is discussed with the FRR, FAR and TSR. Chapter four discusses another highly recommended source of authentication such as face recognition. In this chapter, the algorithm of Performance Comparison of Face Recognition using Transform Domain Techniques (PCFTD) is proposed. The face databases L ?? Spacek, JAFFE and NIR are considered. The features of face are generated using wavelet families such as Haar, Symelt and DB1 by considering approximation band only. The face features are also generated using magnitudes of FFTs. The test image features are compared with database features using Euclidian Distance (ED). The performance parameters such as FAR, FRR, TSR and EER computed using wavelet families and FFT. The methodology described in this paper is accurate, simple, fast and better than the existing algorithms. Chapter five presents conclusion and future work. -
Synthesis, Characterization and Catalytic activity of Zirconia-Ceria catalysts
The development of catalysts is critical for the economical and environmentally efficient generation of chemical compounds that underlie every aspect of our society. Catalysts are key players in research involving the discovery of pharmaceuticals, materials, and polymers. In addition, catalysis is especially powerful in bulk synthesis, allowing the production of compounds, polymers and commodity chemicals via routes that would otherwise be impossible. Ceria is the unique rare earth for which dioxide is the normal stable phase contrary to the others for which Ln2O3 is the normal stoichiometry. The applications of ceria based materials are related to a potential redox chemistry involving Ce(III) and Ce(IV), high affinity of the element for oxygen and sulphur and absorption/excitation energy bands associated with its electronic structure. Zirconium is one of the more abundant elements, and is widely distributed in the Earth's crust. Being very reactive chemically, it is found only in the combined state or as part of a complex of oxides as in zircon, elpidite, and eudialyte. Doping ceria with zirconia may improve the oxygen storage properties of ceria at three different levels. At the level of the microstructure, it inhibits surface diffusion and in turn the loss of surface area at high temperatures. At the microscopic level, substantial doping may result in the formation of an interface structure that facilitates the oxygen transport from bulk to the surface. At the atomic-level, it stabilizes the oxygen defective structure. The texture, structure and thermal stability of ceria-zirconia doped oxides are closely related to the ratio of cerium to zirconium in the solid solution. Chapter 1 comprises of the general introduction of catalysis, importance of solid acid catalysis, sulphated metal oxides, pure ceria, pure zirconia, modified ceria and zirconia. It gives a brief introduction about the nitration of toluene. The aim and objectives of the present investigation are also described at the end of this chapter. Chapter 2 comprises of a thorough literature survey on the significance of solid acid and super acid catalysts in various domains of chemical industry and importance of anion promoted zirconia and ceria catalysts. The definition of ??super acid and their classification vii on the basis of origin of the active sites are also outlined. Importance of modified metal oxides is also outlined. Chapter 3 deals with the experimental procedures and techniques employed in this investigation. Scientific aspects of the precipitation and impregnation methods were outlined. The experimental details of surface area measurements by BET method, application of X-ray powder diffraction studies for crystalline phase and size determination, elemental detection by EDAX, spectral details from FTIR and thermal stability by TGA have been described. Chapter 4 deals with the various characterization results and discussion of pure, doped and sulphated Zirconia-ceria solid acid catalysts. The bulk and surface properties of the catalyst was discussed by XRD, BET surface area, TGA and FTIR. All characterization results revealed that the incorporated sulphate ions has a significant influence on the surface and bulk properties of the ZrO2-CeO2 catalyst. The prepared catalysts are investigated for the liquid phase nitration of toluene under various reaction conditions. Chapter 5 gives with the summary and conclusion of the present study. It also gives the future scope of the present study. On the whole, zirconia-ceria solid acid catalysts were successfully synthesized by simple route. Physicochemical characterization of all these catalysts revealed that the loaded sulphated and doped metal oxides show a significant influence on the surface and bulk properties of the ZrO2 - CeO2. These catalysts are found to be active for the liquid phase nitration of toluene. Key words: Solid acid catalysis, Zirconia-Ceria, Sulphated zirconia-ceria, Nitration of toluene -
Analysis of Web Mining Patterns Using Custom-Built Apriori Algorithm
The dissertation entitled Analysis of Web Mining Patterns Using Custom-Built Apriori Algorithm has developed a custom-built apriori algorithm for the discovery of association rules in web log data. Web server log containing the information about all the web requests to the Christ university website is used for analysis. The methodology adapted by this research is a four step process, containing data preprocessing, frequent pattern discovery, analysis and developing a tool for implementing web mining. The custom built apriori takes the preprocessed weblog file as input and generates the frequent folders and the relationship among them. This thesis has also developed a tool written in java for this web usage mining process. The tool assists the user to execute the custom built apriori algorithm and to view the associations among folders based on the given support and confidence values to the tool. The web is a highly dynamic information source. Most of the organisations put information on the web because they want it to be seen by the world. Now a days the web is well beefed up with more information in an unstructured fashion. As the web and its usage continue to grow, there is an opportunity to analyse web data and extract useful knowledge from it. The objective of this research is to predict the user behaviour in interacting with the website that helps the website designer in improving the quality of website. The dissertation is organised into 5 chapters. Chapter1, Introduction starts with a brief overview of web mining and presents the objective of the study and the problem statement. Chapter 2, Literature review, discusses background work in the field of web mining and pattern discovery. Chapter 3, methodology elaborately discusses the process used for analysing the web patterns. Chapter 4 is dedicated for results and discussion. Chapter5, conclusion, summarises the inferences concluded based on the results obtained. The chapter also discusses the limitations and challenges and concludes with future scope of the study. KeyWords: Web Mining, Preprocessing, Web Server log, Frequent pattern -
Exploration of Personal Identity Among Individuals with Multiple Inter-state Migration Experiences
Migration is an increasingly common phenomenon for various reasons like economic betterment and educational purposes. Migration is also considered a life-event causing psychological distress. Individuals who migrate multiple times, are faced with a challenge of adapting to a new environment multiple times, thus having to give up and incorporate certain elements from the environment into the self, in turn altering their personal identity. This research is focused on exploring the personal identity of individuals who have undergone multiple interstate migrations within India. Life histories of 12 individuals were taken and analysed using thematic analysis. The findings indicate that there are changes in various components of personal identity like certain changes within the family, development of a multicultural perspective, certain cognitive elements like divergent thinking and development of certain personal traits like acceptance. These individuals are highly adaptable to different kinds of environments. They do not have strong attachments with peers. Keywords: personal identity, multiple interstate migrations -
Effective Testing: A case study approach for improving test efficiency
The study presented in this thesis investigates the methods for improving the software test efficiency. Test efficiency measures the cost-effectiveness of a test organisation and it is measured by dividing the number of defects found in a test by the effort needed to perform the test. A review of the literature suggests that software test efficiency improvement depends on direct and indirect success factors like test process, test management, test tools, test object delimitation, test case determination, test infrastructure, configuration management, release management etc. This thesis was a case study approach for improving the test efficiency of an existing test setup in a database environment. Most of the thesis work followed an action based research approach by giving importance to the test setup. Work started with an analysis of the initial test environment, identified the issues and improvement areas in existing test setup and given an implementation proposal for the identified problems. Based on the proposal, team implemented the solutions, which lead to a test environment containing number of actions like automation using standard framework, risk based testing, parallel execution, modularization, avoiding code redundancy and proper test management. The results of the case study suggest that the software products that has multiple releases should seriously consider the test improvement factors like regression environment, risk based testing, light weight test automation etc., in the initial stages of the testing. This will lead to cost savings, quality, flexibility and higher productivity. The investigation further identifies the issues in test management and introduced new method called test point method for proper test execution tracking. Based on the implementation results and their discussions, this study presents a new approach and practical guidelines for improving test efficiency of a software test project. IBM has recognised this case study by giving eminence and excellence award for saving one person year of testing effort in their indexing tool test environment. -
A Study on Measures of Central Tendency of Some Distance Parameters of Connected Graphs
This dissertation sets out to examine the implications of various mea- sures of central tendencies of graphs by introducing the unique concept of ?graphs. A ?graph is defined as a simple, finite, connected and undirected graph in which the basic centrality measures: mean, median and mode of eccentricities are equal. It takes a formal approach to the exploration of ?graphs by applying the principles of Graph Theory. Various graphs are looked into to compare the centrality measures, and the possibility of those being ?graphs. Earlier graph theoretical research in notions of centrality, distance and eccentricity are reviewed. It describes the development of a new elicitation tool that examines the effect of measures of central tenden- cies in graphs, by analyzing their eccentricity sequences. Using this new ap- proach the central values of certain graphs are obtained. The concept found would be helpful to develop a more complex interpretation of the notion of centrality measures in graph theory. Keywords: Eccentricity; Eccentricity sequence; Distance; Degree; Cen- trality; Mean; Mode; Median; ?graph; Central value