Browse Items (1473 total)
Sort by:
-
Morphology of interstellar medium using multi-wavelength obervations
The interstellar medium (ISM) is the matter that exists between the stars in a galactic system. The structure and composition of a galaxy can be understood by a study of the ISM. Our Galaxy is the only place where the observations of the ISM can be resolved and studied in great detail. There are various archived observations from space-based and ground based telescopes spanning a large region of the electromagnetic spectrum. Combining these different observations with one another will help to study the ISM on a large scale. We have compiled some such observations and analyzed the column density data, to study the ISM and make the database available to the scientific community for further investigations. The data was taken from papers published over a span of 60 years (1951 to 2010). The column densities in these papers were derived using different methods and observations from various telescopes operating in different wavelengths. We compiled these diverse data into a single catalogue and analysed the data. We studied the correlations between the line of sight gas and dust and reported new correlations not published before (APJS, 119(1), 8, 2012). We also studied the spatial distribution of the interstellar gas and dust and have estimated the corresponding exponential vertical scale heights. There also exists a wide range of photometric data from various telescopes which can be combined to cover a large range of wavelengths. We have made use of Galaxy Evolution Explorer (GALEX) photometric data in conjunction with Sloan Digital Sky Survey (SDSS) data to obtain the point sources observed by both missions. GALEX observed in two bands simultaneously, the far-ultraviolet (FUV: 1350 1750 and the near-ultraviolet (NUV: 1750 - 2750 , while SDSS observed in five bands u, g, r, i and z, with effective wavelengths ranging from 3551 to 8931 GALEX and SDSS together provide photometric data ranging from the far-ultraviolet to the near-infrared. -
Study of buoyancy and surface tension driven convention in nanaofluid
This thesis presents a detail study of linear and non-linear analysis of buoyancy and surface tension driven convection in nanofluid. The linear Rayleigh-Bard / Rayleigh- Bard Marangoni convection in nanofluids in the presence of external constraints like magnetic field, rotation and newlineinternal heat generation is investigated. The effect of temperature and volumetric concentration modulation of nanoparticles at the boundary and gravity modulation are studied on the onset of Rayleigh- Bard newlineconvection. The obtained results are discussed qualitatively and presented newlinegraphically. The problem discussed have important applications in the field of oceanography, geophysics, nuclear fuel, astrophysics, geothermal reservoirs, engineering and space situations with g-jitter connected with gravity simulation studies.Given the rising relevance of nanofluid application, we discuss four newlineproblems in this thesis whose detail summary is presented below: (i) LINEAR AND WEAKLY NON-LINEAR ANALYSIS OF GRAVITY MODULATION ON THE ONSET OF RAYLEIGH BARD CONVECTION IN NANOFLUID The effect of modulation of gravity or time-periodic body force on newlinethe onset of Rayleigh-Bard convection in nanofluid is studied using newlinelinear and non-linear analysis. The stability of the fluid layer heated from newlinebelow is analysed by considering time-periodic body acceleration. This newlinehappens generally in the vehicles and satellites associated with studies of newlinemicro gravity simulation. In order to study the effect of gravity modulation newlineon the system stability limit, linear and weakly non-linear analysis is performed. Normal mode technique and perturbation method is applied to study linear stability. The critical Rayleigh number and wave number is newlinecalculated by taking modulation of small amplitude. It is found that the critical thermal Rayleigh number can be increase or decrease by a massive amount depending upon the distribution of nanoparticles.In this thesis we considered bottom heavy distribution of nanoparticles. -
Impact of microfinance in socio economic development evidence from south India
The role and impact of microfinance in the socio economic development of the low income people who are not credit worthy has been assessing and exploring by researchers for its sustainable operation and the development of formal financial system. The study explores the socio economic development of microfinance in South India. The objectives are based on variables like financial inclusion, employment and earning opportunities, social inclusion, economic development. social development, personal development. family relationship, economic newlineresilience, social capital, and well-being. The scope of the study is limited to the newlinebeneficiaries of microfinance in four states, namely Andhra Pradesh (undivided),Karnataka, Tamil Nadu and Kerala. The sampling method used in the study is non probability sampling technique of purposive sampling. Both primary and secondary data are used and it is found that microfinance has contributed to financial inclusion, social inclusion and employment and earning opportunities. Besides it has supported substantially social developinent and moderately economic development of the beneficiaries. Further it is noted that it has positive effect on personal development, and family development. Thus it has contributed to develop economic resilience and social capital among low income people which ultimately sustain their well-being, The major findings of the study are: is found that social inclusion, employment and earning opportunity and newlinefinancial inclusion have a significant influence on social development. It is explored that the financial inclusion and employment and earning opportunity can predict the economic development. It is concluded that the financial inclusion and employment and earning opportunity have a significant influence on the family relationship. It is found that the financial inclusion, employment and earning opportunity newlinecan predict the Personal development. It is observed that the personal development newlineand social development can predict the social capital. -
fluorescence diffuse optical tomography : Synthesis characterization and imaging of a novel target specific near infra-red contrast agent for breast cancer detection
Contrast agents are finding profound application in optical imaging of breast cancer for an early detection. In the present work, a novel estrogen receptor (ER) targeted near infra-red fluorescent dye conjugate was synthesized, referred to as Novel Dye Conjugate (nDC) hereafter. nDC is a conjugate of 17and#946;-estradiol with a derivative of indocyanine green dye, bis-1,1-(4-sulfobutyl) indotricarbocyanine-5-carboxylic acid, sodium salt. Structural composition of nDC was validated using Liquid Chromatography Mass Spectrometry (LC-MS) and Hydrogen-1 Nuclear Magnetic Resonance (1H-NMR) technique. MCF-7 and MDA MB 231 Cell lines studies proved the special biding ability of nDC with estrogen receptor positive breast cancer cell lines and its photophysical properties were verified to be in near infrared region (NIR). Similar studies were conducted on ER expressing cancerous tissues like Non-Invasive Ductal Carcinoma, Non-Invasive Lobular Carcinoma, Non-Invasive Adenocarcinoma and Non-Invasive Medullary Carcinoma. In all the above tissues, nuclear level ER binding of nDC was observed leading to the validations of the unique binding properties of the novel dye. Mathematical modeling for tumor to background mapping using nDC was carried out through Fluorescence Diffuse Optical Tomography (FDOT) simulations. Simulation results were also validated using silicone phantom experiments. An array of 8*8 boundary data was collected using frequency domain-FDOT system which was setup indigenously. Commercially available fluorescent dye Indocyanine Green (ICG) was used in the present study for comparative analysis with nDC. When compared to ICG, proposed dye had 1.5-fold higher target to background contrast with respect to fluorescent lifetime in both simulation and phantom studies. Similarly proposed novel dye had a two-fold higher target to background contrast with respect to fluorophore absorption. Above results proved the superiority of nDC compared to ICG on target(tumor) to background ratio enhancement. -
Attitude towards the medical profession among higher secondary students in relation to medical aptitude, parental innfluene, peer influence and perceived social expectations
Attitude towards the medical profession includes concepts, motives or beliefs associated with the profession of medical science. A profession that challenges the intellectual competency of the aspirant to qualify- with soaring expectations from family and society- the demands of the career entail the individual to possess an appropriate attitude and a realistic understanding of it. The current study explores the role of medical aptitude, parental influence, peer influence and perceived social expectations in the formation of attitude towards the medical profession and their differences among higher secondary students based on their gender and type of pre-university college. The study-cum-survey employed a quantitative approach using the paradigm of post-positivism. The participants comprised of 396 second-year pre-university students from colleges of Bangalore South, who were selected by convenience sampling, with Physics, Chemistry and Biology as their core subjects. The findings reveal peer influence to be essential in the development of professionalism and a sense of service mindedness. Parental influence and the higher secondary adolescent s perceived social expectations act as significant predictors in the formation of favourable attitude. However, gender and the type of pre-university colleges bear no significant difference with respect to their attitude towards the profession. The study has set a base on what needs to be focussed in our country on the next generation of medical professionals. It is hoped that educational and medical institutions, policy and curriculum drafters, parents and teachers realise that a combination of sound medical aptitude, parental influence, peer influence and perceived social expectations resonates in the formation of a favourable attitude towards medical science. Assessing those higher secondary students qualifying into medical science would enable to analyse differences that existed, if any, in their entry-level and post-qualifying attitude towards the medical profession. -
Echo mapping of active galacticn nuclei
Active galactic nuclei (AGN) are the persistent high luminosity sources powered by accretion of matter onto super massive black holes (SMBHs) at their centres. They are known to show flux variation and this property can be used as an effective tool to map the extent of the broad line region (BLR) and the dusty torus that surrounds the central SMBH. Though the mass of the SMBH (MBH) can be directly measured using the dynamics of stars that are close to the SMBH, this method is limited to objects in the low redshift Universe (z < 0.1). On the other hand, the technique of reverberation mapping (RM) can provide MBH estimate over a range of redshifts. RM is based on the light travel time delayed response of the line emitting gas as well as the re-processed torus emission to changes in the continuum emission from the accretion disk. As of now, MBH measure-ments are available for more than 100 sources based on RM. The obtained BLR sizes (RBLR) are found to be correlated with the optical luminosity (L5100) at wavelength 5100 This relationship is obtained based on mea-surements of AGN available over a limited range of luminosity. Moreover, many of these measurements also have larger error bars. Therefore, there is an urgent need to increase RM measurements with small errors on more AGN covering a wide range of redshifts to better constrain the RBLR ? L5100 relation. We have carried out photometric reverberation observa- tions on the AGN Mrk 590. Using both broad band (that overlaps with the continuum) and narrow band (that overlaps with the H? emission line) observations, we found the BLR size to be 21.44+1.49 ?2.11 days, which is equiv- alent to 0.018+0.001 ?0.002 pc. Using this measured BLR size and the full width at half maximum of the H? line measured from the newly acquired Subaru spectrum we found a black hole mass of 1.96+0.15 ?0.21 108 M , using virial relationship and adopting a scale factor of 1.12. Similar to BLR reverberation mapping, the extent of the dusty torus in AGN can also be measured using dust reverberation mapping (DRM) based on the delayed response of the near infrared (NIR) flux from the torus to the ionizing UV/optical continuum coming from the accretion disk. From these observations too, a strong correlation is known to exist between the torus size (Rdust) and the optical luminosity (LV). Based on the Rdust ?LV relation, it is also possible to use AGN as standard candle to con- strain the Hubble constant (H0) and other cosmological parameters. But for that, a large number of DRM observations are needed at different red- shifts. As of today, very few NIR interferometric observations are avail-able, but measurements of the torus size via such direct imaging observa-tions are again limited to very near and bright AGN. Moreover, there is a large discrepancy in the size of the torus obtained via the direct imaging method through interferometry and that obtained from DRM. From long term monitoring in the optical and infra-red, we found the inner edge of the dust torus in H0507+164 and Z229?15 to lie at a distance of 0.029+0.010 ?0.008 pc and 0.017+0.005 ?0.005 pc, respectively, from the central optical continuum source. These two new measurements are also found to lie closely on the known Rdust ? LV relation line. Also, by modeling the available BLR RM data in the literature, it is possible to constrain the size, structure and kinemat-ics of the BLR using Bayesian approach. This approach is adopted several times to study the BLR morphology by different ways but is not applied to a large number of sources in an homogeneous manner. From an analysis of the RM data for a total of 57 sources following a Bayesian approach, we could constrain the structure of the BLR in them as well as derive other properties of BLR. -
Foreign Policy of China a Under Deng Xiaoping and its Contemporary Relevance
Political leadership plays an important role in foreign policy decision making in general. Studying leadership traits, styles, beliefs and world view is one of the common methods to comprehend political leaders and their influence on foreign policy. When it comes to authoritarian countries like China, its foreign policy decision making has several layers of which political leaders play all the more crucial role. Irrespective of the period Imperial, Nationalist or Communist the political leaders of China are guided by its history, philosophy and the then existing domestic and global circumstances, in formulating and implementing the country s foreign policy. Political leadership plays an important role in foreign policy decision making in general. Studying leadership traits, styles, beliefs and world view is one of the common methods to comprehend political leaders and their influence on foreign policy. When it comes to authoritarian countries like China, its foreign policy decision making has several layers of which political leaders play all the more crucial role. Irrespective of the period Imperial, Nationalist or Communist the political leaders of China are guided by its history, philosophy and the then existing domestic and global circumstances, in formulating and implementing the country s foreign policy. The central enquiry of the study is to assess contemporary relevance of Deng s foreign newlinepolicy paradigm. Through field visits and rigorous analysis of primary sources, the newlinestudy establishes that relevance of Deng s policy continues in the present context except on China s pro-activeness towards issues pertaining to its territorial integrity and sovereignty. Using China s case, the study advances the framework of understanding pertaining to the role of political leadership in foreign policy making. The study also makes certain broad policy recommendations to various stakeholders for consideration. -
A Study on the impact of foreign investment in infrastructure sector in india
The growth of an economy is determined by the amount of investment made or the capital created in the economy. Capital creation happens when the economy has excess of income over expenditure, in other words, savings. newlineForeign Investment is a good source of fund for developing economies whose savings is low. Hence, opening up the economy for inflow of foreign funds has almost become inevitable in the present situation of liberalization, privatization and globalization. Therefore, all developing economies, including India, are creating opportunities for foreign investments. Infrastructure plays a pivotal role in development of a country. However infrastructure projects require huge investment and the projects take a long time for the projects to be completed. This necessitates investment inflows to originate from the Government, PPP, FDI, etc. Foreign investment through foreign direct investment and Foreign Institutional Investment has newlinebecome a popular source of investment, particularly for financing the projects newlineof infrastructure sector. Foreign funds flow into the firms through investment in the equity of the firms Infrastructure plays a pivotal role in development of a country. newlineHowever infrastructure projects require huge investment and the projects take a long time for the projects to be completed. This necessitates investment inflows to originate from the Government, PPP, FDI, etc. Foreign investment through foreign direct investment and Foreign Institutional Investment has newlinebecome a popular source of investment, particularly for financing the projects newlineof infrastructure sector. Foreign funds flow into the firms through investment in the equiy of the firms Regression analysis is used to ascertain the functional relationship among FDI, Growth, Trade enness, Economic Stability and Energy position. The result of the regression analysis proves that there exists a functional relationship between FDI equity inflows and growth and trade openness. -
Development and effectiveness of an art therapy application for children
This study involved developing an art therapy app and explored the effectiveness of art therapy using the app on enhancing children's self-esteem. Digital technology has become a part of human life and has also influenced mental health services. There is a recommendation to use digital technology in low-resource countries to bridge the mental health service gap for individuals with mental health problems. To meet the needs of art therapists and clients, an app called Art about Me was designed as a new medium/tool in art therapy intervention by the researcher, an art therapist. Confidentiality, security, documentation, and a backing up system were the primary features considered while developing the app. Three school counselors who participated in an art therapy workshop provided art therapy intervention using the app for children in school settings to improve their self-esteem. The results indicated that art therapy using the app was significantly effective in enhancing their self-esteem. This study concluded that the app could replace traditional art materials and work as a substitute medium. It helped build a therapeutic alliance with clients, develop self-growth and potential for children, and was appreciated by counselors. The art therapy app would be an adequate solution to provide therapeutic services and overcome the limitation of art materials for art therapy, especially in low- resource countries. -
Self-care practices, professional quality of life and challenges : An exploration among counsellors in Kerala
The profession of counselling continues to prove its importance in today's fast- paced world, where pausing down and listening to someone are becoming an odd and luxurious concern of people. The counsellor may feel as though they are in a marathon, which demands them to continuously offer unconditional positive regard and empathy for their clients. This may leave them incapacitated to look into themselves and to recognize what is happening to them in this process of caring for others. Though profound discourses take place in the international scenario about the criticality of rendering to the need and well- being of counsellors, evidence-based studies, and effective interventions in this regard are still lacking in the Indian context. This study seeks to fill this gap by exploring, how the positive and negative feelings of continuous caring can affect the professional quality of life of counsellors, what are the self-care mechanisms they adopt, and which are the professional issues they find most concerning. To meet these objectives, the present research employs a mixed- method design in a sequential explanatory fashion. The study encompasses three different phases wherein phase I and II; the sample consisted of counsellors working in various government projects in Kerala selected through dense sampling method and purposive sampling method respectively. In phase III, counsellor experts with more than 20 years of experience in the field are considered through purposive sampling. Findings describe that counsellors tend to follow an unbalanced self-care routine with significantly less focus on professional aspects. The presence of a high risk of burnout and secondary traumatic stress with a moderate feeling of compassion satisfaction call for immediate interventions for counsellors. Lack of benefits, safety issues, concerns about professional identity, poor working conditions, absence of career prospects, and lack of professional credentials are the major challenges identified by the counsellors. Considering these challenges, a set of recommendations are proposed by counsellor experts, which suggest reformations at both the systemic level and academic formation. Specific recommendations are also listed on the development of personal self and professional self for safe, effective and ethical practice of counsellors across a variety of practice settings. Implications exist for policymakers and counsellor educators to create an avenue for supporting a healthier and sustainable counsellor workforce. -
Polyvinyl alcohol and epoxy based composites for radition shielding applications
The present study has been focused towards designing efficient, non-toxic and cost-effective shielding materials with good mechanical strength for protection against radiations encountered in various environments like aerospace, hospitals, research and nuclear reactor establishments. From this perspective, to impart desired shielding properties, high Z filler dispersed polymer matrices such as Bi/WO3-polyvinyl alcohol (PVA), Ta2O5-epoxy, Ta2O5-Bi2O3-epoxy, micro Bi2O3-epoxy and nano Bi2O3-epoxy with varying filler contents have been synthesized. Structural characterizations were carried out using X-ray diffraction newline(XRD) and Fourier transform infrared (FT-IR) spectroscopy to reveal the interactions newlinebetween filler and polymer matrix. The morphological analyses were performed using newlinescanning electron microscopy (SEM) images. The AC conductivity measurements and newlineoptical studies revealed low conductivity property of the composites. The thermo newlinegravimetric analysis (TGA) and mechanical studies were conducted to ascertain thermal newlinestability and mechanical properties of the composites. With increase in filler concentration mechanical properties of Bi/WO3-PVA composites were found to be weakening. The TGA studies of Bi/WO3-PVA composites showed decrease in peak degradation temperature with increase in filler content. This prompted us to further design epoxy composites as epoxy matrix has good thermal stability and mechanical strength. Compared to neat epoxy, dispersion of varying wt% of Ta2O5 and Bi2O3 into epoxy matrix led to significant improvement in stiffness, storage modulus, glass transition temperature and thermal stability of the composites. Epoxy composites with 5 wt% of Ta2O5 and 30 wt% of Bi2O3 revealed better thermal and tensile properties when compared to same wt% Bi2O3 filled epoxy composites. The synergistic influence of micro and nano Bi2O3 filler on epoxy matrix composites showed similar thermal behaviour. -
Classification of extragalactic point sources and flux variability characteristics of blazars
Classification of different types of astronomical objects in large surveys usually done through spectroscopy requires enormous amounts of time. Hence, many attempts have been made using broad band photometric magnitudes and spectroscopic observations to classify the sources, particularly extragalactic sources such as active galactic nuclei (AGNs), starburst galaxies and newlinenormal galaxies. However, a method which does not involve spectroscopic data would be ideal. With this in view, in this work we have made an effort to classify a sample of 37,492 point sources into Quasi-Stellar Objects (QSOs), galaxies and stars using template fitting technique and multiwavelength photometric magnitudes from the Sloan Digital Sky Survey (SDSS) and newlinethe Galaxy Evolution Explorer (GALEX) with coverage from the optical (z: 8931 to the far ultraviolet (FUV: 1516 . Templates for QSOs, galaxies and stars were used to fit the data of the objects to the seven photometric bands of SDSS and GALEX. The results were compared with SDSS spectroscopic classification. Two UV bands (NUV and FUV) were included to remove the possible degeneracies in the classification based only on optical bands or in color-color method. UV bands play a crucial role in the classification and characterization of astronomical objects that emit over a wide range of wavelengths, especially for those that are bright at UV. Classification using template fitting method is consistent with spectroscopic methods, provided UV information of the objects is available. UV bands are particularly important for separating quasars and stars, as well as spiral and starburst galaxies. We have achieved the efficiency of 89% for QSOs, 63% for galaxies and 84% for stars. Objects for which spectroscopic data is not available can also be classified using this method which does not require spectroscopic information. -
Strategies to manage power outages and optimize energy cost for developing countries through supply and demand side management
Developing Countries like India, face huge amounts of power cuts starting from a few hours to few days. Some of the main reasons are transmission and distribution losses, theft, lack of smart infrastructure, poor newlinemaintenance of the existing systems, lack of smart algorithms etc., Due to this reason consumers have moved to back up systems to feed their loads. Tonnes of diesel has been consumed through generators, due to power cuts, because to this consumers are suffering to pay extra cost for electricity as their energy bills are an addition of grid cost as well as the back up cost.The load dispatch centers will implement load shedding leading to a compete outage in a few areas. As a result the consumers in these areas newlineimmediately turn on their back up sources leading to an increase in energy cost. There are no smart algorithms used either to distribute the power at the utility end or to manage the loads during an outage, especially when the loads are running on back-up supply. This report suggests some smart algorithms to provide partial power to consumers rather than a complete outage, load shifting techniques to the consumers at the time of an outage so that they can optimize their back up cost, last but not the least smart newlineintegration of solar power to the consumers to optimize the over all energy costs. newlineThe partial outage algorithm results, in supplying partial power to consumers rather than a complete outage condition this is achieved by implementing a simple unitary method based on the power consumption of the newlineconsumers. By supplying partial power, the consumers can save a certain amount of expenditure on back up cost especially from diesel generators and also utilize the on grid solar generation if the consumer is having a solar roof top installation. -
Models for load forecasting and demand response
Increasing pressure on the utilities to accommodate energy efficiency, load management and progress in advanced technology has led to transformations of existing grids into smarter grids. With the development of Smart Grid Technology and the integration of smart meters it is possible to control the equipment installed at the consumer site. Creating awareness among the end- users to participate in load management programs instead of capacity addition is the best solution for maintaining the stability in the grid. Utilities can also encourage consumer participation in load control activities. They can ensure that power is given to a consumer during his priority time. For this, loads have to be categorized, prioritized and then considered for load shedding so that revenue loss and social impacts of load shedding are minimized. It would be beneficial if a consumer's load is not completely shed during load shedding. Amount of power that is shed from a consumer can be limited and consumers can be allowed to adjust their loads based on the availability of power and get incentives from the utilities for their change in load pattern. Consumers are also benefited with the reduced energy charges on the consumed energy during these periods. Review of the recent research work shows that demand response and load forecasting play an important role to relieve the power system from economic and environmental constraints. Various approaches have been used in the past for developing different demand response and forecasting methodologies including neural networks, fuzzy logic and statistical techniques. These methodologies fluctuate in complication, suppleness, and information necessity. In addition, statistical methods such as time series, regression, and state space methods have large numerical deviation in the predicted load series. In general, for accurate modeling of nonlinear and undecided type of load behavior, artificial intelligence-based techniques are employed. Also, these methods concentrate mainly on ordinary system conditions. However, proposing the possible Demand Response strategies to maintain power system security constraints in unpredicted turbulences pose a serious challenge. In the undertaken research, a novel load forecasting method using hybrid Genetic Algorithm Support Vector Regression model has been proposed. The forecast error is around 1-2%. The second part of the work focuses on formulation of demand response strategies based on time of the day and load prioritization. A Unique grading method has been proposed to prioritize the loads and load management during power deficiency by controlling the loads individually using different optimization techniques. The performance of three well recognized population based meta-heuristic algorithms such as Genetic Algorithm, Ant Colony Optimization and Particle Swarm Optimization, to solve load management at the consumer level in the Smart Grid environment were examined in terms of their efficiency, effectiveness and consistency in obtaining the optimal solution. In the last part of the work the Demand Response model for residential load is proposed to minimize the energy cost of the electricity usage by shifting the loads from peak period to off-peak period with the help of intelligent techniques such as Artificial Bee Colony Algorithm. -
An Investigative approach to hard machining of inconel 718 with coated carbide tool
Super alloys sustain good strength at high temperature and pressure conditions. Such newlinematerials have high demand in Aerospace industry, Marine industry, and Nuclear power plants. They have a great demand in Nuclear and Aerospace applications because of it retain its properties at temperature over 700 C. Machinability of nickel based super - alloys is extremely poor, mainly due to their low thermal conductivity, build up edge and self-hardening, which leads to high dynamic cutting forces. They are difficult to machine because of its high shear strength, work hardening and precipitation hardening. High abrasive particles in its microstructure and tendency forming chip to weld to tool and form Built Up Edge (BUE) make it more difficult to machine. Friction between tool and material and its low thermal conductivity newlineresults in high temperature generation. They have Nickel (Ni), Chromium (Cr), Ferrous (Fe) or Cobalt (Co) as base contains. Small amount of Al, Ti, Nb, Ta, W, Mo added to these alloys to sustain at high temperature. Chromium is important alloying element in order to obtain the hot corrosion resistance property. Due to these factors the tool wear is extremely high and increasing the tool life by minutes is an enormous success. To overcome this situation, various newlinematerials have been developed for Inconel 718 machining. Though Ceramic tools, Silicon newlineCarbide whiskers, reinforced alumina tools, carbide tools have been used to machine Inconel 718 but they have failed to produce good surface, better accuracy and minimum tool wear. The present study is to improvise the surface roughness, reduce tool wear and create better machining parameters for extensive use of the material. Taguchi methodology, Grey Relational Analysis (GRA) and Response Surface Methodology (RSM) have been used to analyze the cutting parameters and determine better response parameters for the machining characteristics of Inconel 718. -
Study of the diffuse ultraviolet background radiation at high galactic latitudes
The diffuse background radiation is observed throughout the whole sky and across every wavelength of the electromagnetic spectrum. The study of this background is of great importance as it contains photons coming from a va- riety of astrophysical environments, traveling over the time scales of a few hundred light years to the age of the universe itself. After the discovery of the cosmic microwave background, the diffuse sky in all the other wave- lengths was studied with great interest as they could provide useful insights into the formation history of the universe. In the work outlined in this the- sis, I will be describing this diffuse background radiation observed in the ultraviolet (UV) region. Over more than three decades of observations of the diffuse sky in the UV has revealed our lack of understanding of all the components that con- tribute to the observed background sky in this wavelength region. Initial studies arrived at controversial conclusions with one group suggesting that most of the observed diffuse surface brightness is due to the dust scat- tered starlight while another group suggested contribution from an exotic component along with the dust scattered component. We will explore this background sky in detail by trying to identify individual components and quantify its contribution at various regions in the sky. We have started our analysis at the Galactic pole regions with |b| > 80 using the data from Galaxy Evolution Explorer (GALEX) in the ultravio- let band. A major Galactic component of the diffuse sky in the UV is the starlight scattered by interstellar dust (also called Diffuse Galactic Light: DGL). We chose to study the Galactic poles due to the low dust environ- ment in these regions and easier modeling of the DGL component. We found consistent offsets in the UV data at a level of 230 290 photons s?1 cm?2 sr?1 1 (hereafter photon units) in the far-UV (FUV: 1539 and 480 580 photon units in the near-UV (NUV: 2316 when the UV surface brightness was compared with Galactic tracers like E(B-V) and the infrared surface brightness. These offsets represent the UV brightness at zero column densities. Part of this offset comes from the extragalactic background light (EBL) originating in background galaxies, Quasi-Stellar Objects (QSOs), etc. After careful estimation of this EBL component, we found a residual UV surface brightness of about 120 180 photon units in the FUV and 300 400 photon units in the NUV. The DGL component came to be about 120 photon units in these regions. We also found evidence for contribution from molecular hydrogen fluorescence at a column density of log NH > 20.2 (NH is in cm?2). We conclude that this contribution from H2 is from the cirrus features present at high Galactic latitudes. We further confirmed our findings at the north and south Galactic poles by studying the region between latitudes 70< b < 80 where we found similar offsets and the fluorescence contribution from H2 at the same levels as in the NGP. We proposed a possible contribution to the observed residual surface brightness coming from Hawking evaporation of Primordial Black Holes. But the level of this radiation was not sufficient to account for the entirety of the observed excess. The failure of this explanation only further deepens the mystery of the source of the excess surface brightness of the UV sky. -
Relationship beetween competencies and performance of management teachers of B-school in Bengaluru city
The concept of competency mapping is an established practice in the corporate world for ages. It has been successful in contributing for performance management. The study was aimed to find out whether newlinesimilar efforts can be made in management education. Researcher aimed to develop a competency mapping tool and to study the relationship between competencies and performance of B School faculty members in newlinethe city of Bengaluru. As an outcome of the study a competencymapping tool was developed with five key competency clusters namely Teaching Learning, Assessment Evaluation, Research Publication, Student Development and Administration Coordination. The heads of departments were also part of the study to suggest the desired level of competency levels. Faculty members were asked to rate newlinethe existing level of competencies which they feel they possess. Later the gaps were identified between existing and desired level of competencies in all clusters. Significant differences were found in the assistant professor level with respect to research and publication competency where in Heads newlineof departments expectations were more than the actual level of perceptions. In most other category faculty perception was higher than the Heads perception about competency levels. In case of associate professor newlineand professor category, the overall expected competency level was higher than the faculty perception hence making a strong case of competency gap. While analysing the relationship between competencies and newlineperformance Teaching Learning competencies had the highest relation with overall dimensions followed by Assessment Evaluation newlinecompetencies Study also aimed at exploring the relationship between demographic factors and competencies. Significant difference in the perception did not exist in the gender but in the significant difference was newlineexisting in experience, type of B-Schools belongs to and Courses taught.