Jaison, C A; Dr.Sivanandan, Achari V(Cochin University of Science And Technology, October , 2012)
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Abstract:
Everywhere, on the coastal belt it is proved without doubt that the pristine ground
water quality was severely deteriorated after the 26 December 2004 Indian Ocean
Tsunami. But how far is more relevant, as it is decided by the so-called pre-tsunamic
situation of the region. In water quality studies it is this reference finger print which
earmarks regional ground water chemistry based on which the monthly variability
could rationally be interpreted. This Ph D thesis comprises the testing and evaluation of the facts: whether there is any significant difference in the water quality parameters under study between stations
and between months in Tsunami Affected Dug Wells (TADW). Whether the selected
water quality parameters vary significantly from BIS and WHO standards. Whether
the water quality index (WQI) differ significantly between Tsunami Affected Dug
Wells (TADW) and Bore Wells (BW). Whether there is any significant difference in
the water quality parameters during December 2005 and December 2008. Is there any
significant change in the Water Quality Parameters before 2001 and after tsunami
(2005) in TADW.
Description:
School of Environmental Studies, Cochin University of Science and Technology
Tina,Sebastian; Dr.Sudha Kartha,C; Dr.Vijayakumar, K P(Cochin University of Science & Technology, August , 2009)
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Abstract:
Aim of the present work was to automate CSP process, to deposit and
characterize CuInS2/In2S3 layers using this system and to fabricate devices using
these films.An automated spray system for the deposition of compound
semiconductor thin films was designed and developed so as to eliminate the manual
labour involved in spraying and facilitate standardization of the method. The system
was designed such that parameters like spray rate, movement of spray head, duration
of spray, temperature of substrate, pressure of carrier gas and height of the spray head
from the substrate could be varied. Using this system, binary, ternary as well as
quaternary films could be successfully deposited.The second part of the work deal with deposition and characterization of
CuInS2 and In2S3 layers respectively.In the case of CuInS2 absorbers, the effects of
different preparation conditions and post deposition treatments on the optoelectronic,
morphological and structural properties were investigated. It was observed
that preparation conditions and post deposition treatments played crucial role in controlling the properties of the films. The studies in this direction were useful in
understanding how the variation in spray parameters tailored the properties of the
absorber layer. These results were subsequently made use of in device fabrication
process.Effects of copper incorporation in
In2S3 films were investigated to find how the diffusion of Cu from CuInS2 to In2S3
will affect the properties at the junction. It was noticed that there was a regular
variation in the opto-electronic properties with increase in copper concentration.Devices were fabricated on ITO coated glass using CuInS2 as absorber and
In2S3 as buffer layer with silver as the top electrode. Stable devices could be
deposited over an area of 0.25 cm2, even though the efficiency obtained was not high.
Using manual spray system, we could achieve devices of area 0.01 cm2 only. Thus
automation helped in obtaining repeatable results over larger areas than those
obtained while using the manual unit. Silver diffusion on the cells before coating the
electrodes resulted in better collection of carriers.From this work it was seen CuInS2/In2S3 junction deposited through
automated spray process has potential to achieve high efficiencies.
Description:
Department of Physics,
Cochin University of Science and Technology
Jeevanand, E S; Dr.Unnikrishnan Nair, N(December 20, 1993)
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Abstract:
This thesis Entitled Bayesian inference in Exponential and pareto populations in the presence of outliers. The main theme of the present thesis is focussed on various estimation problems using the Bayesian appraoch, falling under the general category of accommodation procedures for analysing Pareto data containing outlier. In Chapter II. the problem of estimation of parameters in the classical Pareto distribution specified by the density function. In Chapter IV. we discuss the estimation of
(1.19) when the sample contain a known number of outliers under three different data generating mechanisms, viz. the exchangeable model. Chapter V the prediction of a future observation based on a random sample that contains one contaminant. Chapter VI is devoted to the study of estimation
problems concerning the exponential parameters under a k-outlier model.
Description:
Department of
Mathematics and Statistics, Cochin University of Science
and Technoloy
James, Kurian; Dr.Saseendran Pillai,P R(Cochin University of Science & Technology, October , 2008)
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Abstract:
ACCURATE sensing of vehicle position and attitude is still a very challenging
problem in many mobile robot applications. The mobile robot vehicle applications
must have some means of estimating where they are and in which direction they are
heading. Many existing indoor positioning systems are limited in workspace and
robustness because they require clear lines-of-sight or do not provide absolute, driftfree
measurements.The research work presented in this dissertation provides a new approach to
position and attitude sensing system designed specifically to meet the challenges of
operation in a realistic, cluttered indoor environment, such as that of an office
building, hospital, industrial or warehouse. This is accomplished by an innovative
assembly of infrared LED source that restricts the spreading of the light intensity
distribution confined to a sheet of light and is encoded with localization and traffic
information. This Digital Infrared Sheet of Light Beacon (DISLiB) developed for
mobile robot is a high resolution absolute localization system which is simple, fast,
accurate and robust, without much of computational burden or significant processing.
Most of the available beacon's performance in corridors and narrow passages are not
satisfactory, whereas the performance of DISLiB is very encouraging in such
situations. This research overcomes most of the inherent limitations of existing
systems.The work further examines the odometric localization errors caused by over
count readings of an optical encoder based odometric system in a mobile robot due to
wheel-slippage and terrain irregularities. A simple and efficient method is investigated and realized using an FPGA for reducing the errors. The detection and correction is
based on redundant encoder measurements. The method suggested relies on the fact
that the wheel slippage or terrain irregularities cause more count readings from the
encoder than what corresponds to the actual distance travelled by the vehicle.The application of encoded Digital Infrared Sheet of Light Beacon (DISLiB)
system can be extended to intelligent control of the public transportation system. The
system is capable of receiving traffic status input through a GSM (Global System
Mobile) modem. The vehicles have infrared receivers and processors capable of
decoding the information, and generating the audio and video messages to assist the
driver. The thesis further examines the usefulness of the technique to assist the
movement of differently-able (blind) persons in indoor or outdoor premises of his
residence.The work addressed in this thesis suggests a new way forward in the
development of autonomous robotics and guidance systems. However, this work can
be easily extended to many other challenging domains, as well.
Description:
Department of Electronics,
Cochin University of Science and Technology