STUDIES ON SCATTERING AND QUASI-NORMAL MODES IN BLACK HOLE SPACE-TIMES

The question of stability of black hole was first studied by Regge and Wheeler who investigated linear perturbations of the exterior Schwarzschild spacetime. Further work on this problem led to the study of quasi-normal modes which is believed as a characteristic sound of black holes. Quasi-normal modes (QNMs) describe the damped oscillations under perturbations in the surrounding geometry of a black hole with frequencies and damping times of oscillations entirely fixed by the black hole parameters.In the present work we study the influence of cosmic string on the QNMs of various black hole background spacetimes which are perturbed by a massless Dirac field.

A Study of the impact of ISO 9001:2000 on Quality Management Practices in Selected Organisations in Kerala

The research work which was carried out to study the impact of ISO 9001: 2000, in selected organisations in Kerala, spread over various types of activities, such as fabrication of aero space hardware, glass ware, construction industries, health care units etc, encompassing, government and private enterprises, public sector undertakings, small and medium scale industries and research and development establishments. The ambience, work culture and collaboration prevalent in these organisations were varying on account of the environment in which they have been working. Fifty percent of the organizations selected for the study had obtained the ISO 900 I: 2000-certification since seven years or more. The process of study undertaken could invoke interest in the respondents, when a brief explanation on the purpose and need of the study was given to them prior to conducting the survey. There has been total cooperation from the management and the employees of all the organisations for the conduct of the study. Personal discussions were held with the senior management to draw their total support and involvement for the study.

Efficiency in Delivering Obstetric Care-A Comparison of Public and Private Hospitals in Ernakulam District

Department of Applied Economics, Cochin University of Science and Technology

Development of Free Space Method for Material Characterisation and GPR Study & A Case Study on Biological Samples

The thesis mainly focuses on material characterization in different environments: freely available samples taken in planar fonn, biological samples available in small quantities and buried objects.Free space method, finds many applications in the fields of industry, medicine and communication. As it is a non-contact method, it can be employed for monitoring the electrical properties of materials moving through a conveyor belt in real time. Also, measurement on such systems at high temperature is possible. NID theory can be applied to the characterization of thin films. Dielectric properties of thin films deposited on any dielectric substrate can be determined. ln chemical industry, the stages of a chemical reaction can be monitored online. Online monitoring will be more efficient as it saves time and avoids risk of sample collection.Dielectric contrast is one of the main factors, which decides the detectability of a system. lt could be noted that the two dielectric objects of same dielectric constant 3.2 (s, of plastic mine) placed in a medium of dielectric constant 2.56 (er of sand) could even be detected employing the time domain analysis of the reflected signal. This type of detection finds strategic importance as it provides solution to the problem of clearance of non-metallic mines. The demining of these mines using the conventional techniques had been proved futile. The studies on the detection of voids and leakage in pipes find many applications.The determined electrical properties of tissues can be used for numerical modeling of cells, microwave imaging, SAR test etc. All these techniques need the accurate determination of dielectric constant. ln the modem world, the use of cellular and other wireless communication systems is booming up. At the same time people are concemed about the hazardous effects of microwaves on living cells. The effect is usually studied on human phantom models. The construction of the models requires the knowledge of the dielectric parameters of the various body tissues. lt is in this context that the present study gains significance. The case study on biological samples shows that the properties of normal and infected body tissues are different. Even though the change in the dielectric properties of infected samples from that of normal one may not be a clear evidence of an ailment, it is an indication of some disorder.ln medical field, the free space method may be adapted for imaging the biological samples. This method can also be used in wireless technology. Evaluation of electrical properties and attenuation of obstacles in the path of RF waves can be done using free waves. An intelligent system for controlling the power output or frequency depending on the feed back values of the attenuation may be developed.The simulation employed in GPR can be extended for the exploration of the effects due to the factors such as the different proportion of water content in the soil, the level and roughness of the soil etc on the reflected signal. This may find applications in geological explorations. ln the detection of mines, a state-of-the art technique for scanning and imaging an active mine field can be developed using GPR. The probing antenna can be attached to a robotic arm capable of three degrees of rotation and the whole detecting system can be housed in a military vehicle. In industry, a system based on the GPR principle can be developed for monitoring liquid or gas through a pipe, as pipe with and without the sample gives different reflection responses. lt may also be implemented for the online monitoring of different stages of extraction and purification of crude petroleum in a plant.Since biological samples show fluctuation in the dielectric nature with time and other physiological conditions, more investigation in this direction should be done. The infected cells at various stages of advancement and the normal cells should be analysed. The results from these comparative studies can be utilized for the detection of the onset of such diseases. Studying the properties of infected tissues at different stages, the threshold of detectability of infected cells can be determined.

Buried-object detection using free-space time-domain near-field measurements

The detection of buried objects using time-domain freespace measurements was carried out in the near field. The location of a hidden object was determined from an analysis of the reflected signal. This method can be extended to detect any number of objects. Measurements were carried out in the X- and Ku-bands using ordinary rectangular pyramidal horn antennas of gain 15 dB. The same antenna was used as the transmitter and recei er. The experimental results were compared with simulated results by applying the two-dimensional finite-difference time-domain(FDTD)method, and agree well with each other. The dispersi e nature of the dielectric medium was considered for the simulation.

Capital expenditure decision in private and public sector entreprises in India A comparative evaluation

This study is focussed on public and private sector The study is confined to industrial Public companies in the states of Kerala and Orissa along with companies in India. undertakings only. sector and private sector private sector companies in other states were studied. Even though the original plan of 190 companies as the sample size could not be accomplished, as the responses were very poor, but data could be collected frmn 6 public and 5 private sector companies in Kerala, 8 public and 8 private sector companies in Orissa along with 27 private sector companies in other states totalling to 54 companies. The number of years of data collected varies from 2 years to 6 years. Factors which are affecting capital expenditures and hence leading to the performance of private sector compared to public sector companies are studied. After the study and analysis, comparisons are made between public sector and private sector, and suitable recomendations are made so that public sector industries can also perform equally well as the private sector industries in India.

Private and Co-operative Granite Quarries in Thrissur District - A Comparative Study

The study is confined to non-mechanised private and cooperative granite quarries in Thrissur district. There are 90 non -mechanised quarries in Thrissur district. Data were collected for the period from 1994-'95 to 1999-2000. 315* March of every year was considered as the closing date of the year. It envisages an analysis of various problems connected with quarrying operations, financial analysis, cost analysis, demand and supply position of quarry products and socio-economic background of workers. It also suggest some measures to improve the working conditions of granite quarrying.

“A Study on Human Resource Management Practices in Private Hospitals in Kerala”

The healthcare sector in Kerala is witnessing a spiralling growth due to the healthy economic development and the serious outlook of individuals towards personal health. Private sector is thriving exuberantly well since there is a wide gap between demand and supply for healthcare due to the lack of government initiatives. The proliferation of these private hospitals have paved the way for many unhealthy practices like poor working conditions, low wages, excess workload and lack of retirement and welfare measures to the employees. This state of affairs demanded a serious investigation into the functioning of the private hospitals in Kerala, especially on the human resource management practices, as the success of every organisation depends on the satisfaction level of its employees, which, in turn, will benefit the consumer, i.e., the patients. Hence the present study was undertaken to find out the extent of human resource management practices in private hospitals in Kerala with a view to suggest appropriate remedial measures wherever required