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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. -
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EFFECT OF NON UNIFORM BASIC TEMPERATURE GRADIENT ON THE ONSET OF RAYLEIGH-BNARD CONVECTION IN MAXWELLS VISCOELASTIC FLUID WITH MAXWELL-CATTANEO LAW
The effects resulting from the Maxwell-Cattaneo law in Rayleigh-B??nard convection in Maxwells viscoelastic fluid are studied using the Galerkin technique. The effects of one linear and five nonlinear basic temperature gradients are studied on the onset of convection. The Eigenvalue is obtained for free-free, rigid-rigid, rigid-free, velocity boundary combinations with isothermal boundaries. A linear stability analysis is performed. The influence of various parameters on the onset of convection has been analyzed. -
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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. -
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EFFECT OF SECOND SOUND ON THE ONSET OF RAYLEIGH-B??NARD-MARANGONI MAGNETO CONVECTION
The effects resulting from the substitution of the classical Fourier law by the non-classical Maxwell-Cattaneo law in Rayleigh-B??nard-Marangoni convection in an electrically conducting Newtonian fluid are 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 boundaries. In the case of Marangoni and Rayleigh-B??nard-Marangoni convection the eigenvalues are obtained for an upper free / adiabatic and a lower rigid / isothermal boundaries. A linear stability analysis is performed. The influence of various parameters on the onset of convection has been analyzed. The classical approach predicts an infinite speed for the propagation of heat. The present non-classical theory involves a wave type heat transport (SECOND SOUND) and does not suffer from the physically unacceptable drawback of infinite heat propagation speed. It is found that the results are noteworthy at short times and the critical eigenvalues are less than the classical ones. -
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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. -
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. -
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Effectiveness of Awareness Program in Raising Teachers Awareness about Learning Disabilities
??Learning Disabilities is a term associated with difficulties in reading, writing, doing Maths and motor coordination. Awareness about learning disabilities is required for early identification and further remediation. A learning disability in a child can be identified as early as in toddler stage. Teachers are the first ones , usually to suspect a learning disability in a child. For appropriate observation and referrals for further assessment , a teacher should be aware of the various characteristics of learning disabilities which differs from individual to individual. Literature says that there is need of raising the awareness of teachers about learning disabilities and its various etiological factors. Awareness program could help in enhancing the knowledge of teachers in this regard. The current study was organised with an aim of conducting an awareness program to raise teachers knowledge about learning disabilities. 20 teachers, teaching in a Government school in Thiruvananthapuram, Kerala was selected for the study. A pre experimental study pre post without control was designed. The intervention package was framed with comprehensive information about the concept, characteristics, kinds, signs, symptoms, strategies and guidelines for early identification. The awareness of the teachers prior to and post intervention was assessed using a semi structured questionnaire. The effectiveness of the awareness program was gauged using statistical analysis. The findings of the study proved that the knowledge of the teachers about learning disabilities has significantly increased post intervention. The knowledge level was shifted from moderate level, prior to intervention to high level post intervention. The feedback from the teachers ascertained that the program was very useful and interesting. Awareness programs of similar kind are recommended in a broader spectrum. -
EFFECTIVENESS OF BILLBOARD ADVERTISING IN REAL-ESTATE AND AUTOMOBILE ADVERTISING
Advertising is one of the important types of communication in todays world and it has become an indispensable for both the consumer and the producer of it. Advertising plays an important role in the integrated marketing communication. In todays information age it is necessary for an organization or institution make the public aware of their goods and services and advertising acts as tool to serve this purpose. There are various types of advertising such as Out-door Advertising, In-door advertising, Non-product advertising, Radio advertising, Television advertising, National advertising, International advertising, Retail advertising, classified advertising and local advertising to name a few. Outdoor advertising is less touched subject within the field of advertising. Though there have been some research on the creative execution, improving attention to the billboards there is not much attention given to examine the effectiveness of billboard advertising. Billboards as a medium of advertising have been used by the advertisers in various parts of India. It is normally situated along the traffic prone roads, main streets, commercial centres, on flyovers and on highways. The purpose of it is to make people (pedestrians, drivers, and passengers) aware of the products and services which are available in the market and which intern leads to the buying and selling between consumer and manufacturer. In todays world the outdoor advertising, especially billboard advertisements are used extensively by the Real-estate and Automobile advertisers. It is important to know are people noticing these billboard advertisements and how it is influencing the people in their purchase decision making process of these Goods being advertised. It is also important to know why do Real-estate and Automobile advertisers prefer advertising on billboards rather than other media such as television, Radio and Print. -
EFFECTIVENESS OF FILMS IN PROPAGATING ENVIRONMENTAL ISSUES- A comparison between live action and animation films - A comparison between live action and animation films
The thesis aims at finding out which is a better medium to communicate environmental issues. For the purpose of the research, four films were selected, two live action films and two animation films. 2012 and 8 Below are the two live action films and Wall-E and Madagascar are the two animation films. The study had a sample of 86 people, 45 females and 41 males respectively between the age group of 18 to 28 years. A survey was conducted, consisting of four questions each for the four films. The questions were devised to find out the theme of the films, whether or not the film has scientific grounding and if yes as to the reason why. After tabulating and analysing the results it can be seen that animation films are more popular as 76% of the sample has seen the animation films and majority of the sample believes the films have scientific grounding and that the issues and rendered in a comic fashion. 2012 and Madagascar have been watched equally by the sample, both of them have 80 percent. -
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