Abhilash, S; Dr.Mohan Kumar, K(Cochin University of Science and Technology., December , 2007)
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Abstract:
The main purpose of the thesis is to improve the state of knowledge and understanding
of the physical structure of the TMCS and its short range prediction. The present
study principally addresses the fine structure, dynamics and microphysics of severe convective
storms.The structure and dynamics of the Tropical cloud clusters over Indian region is not well
understood. The observational cases discussed in the thesis are limited to the temperature
and humidity observations. We propose a mesoscale observational network along with all
the available Doppler radars and other conventional and non—conventional observations.
Simultaneous observations with DWR, VHF and UHF radars of the same cloud system will
provide new insight into the dynamics and microphysics of the clouds. More cases have to
be studied in detail to obtain climatology of the storm type passing over tropical Indian
region. These observational data sets provide wide variety of information to be assimilated
to the mesoscale data assimilation system and can be used to force CSRM.The gravity wave generation and stratosphere troposphere exchange (STE) processes
associated with convection gained a great deal of attention to modem science and meteorologist.
Round the clock observations using VHF and UHF radars along with supplementary
data sets like DWR, satellite, GPS/Radiosondes, meteorological rockets and aircrafl
observations is needed to explore the role of convection and associated energetics in detail.
Description:
Department of Atmospheric Sciences,
Cochin University of Science and Technology
Shaji,S; Abdul Rasheed, T M(Cochin University of Science and Technology, April , 2003)
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Abstract:
The present work is mainly concentrated on setting up a NIR tunable diode laser absorption (TDLA) spectrometer for high-resolution molecular spectroscopic studies. For successfully recording the high-resolution tunable diode laser spectrum, various experimental considerations are to be taken into account like the setup should be free from mechanical vibrations, sample should be kept at a low pressure, laser should be in a single mode operation etc. The present experimental set up considers all these factors. It is to be mentioned here that the setting up of a high resolution NIR TDLA spectrometer is a novel experiment requiring much effort and patience. The analysis of near infrared (NIR) vibrational overtone spectra of some substituted benzene compounds using local mode model forms another part of the present work. An attempt is made to record the pulsed laser induced fluorescence/Raman spectra of some organic compounds. A Q-switched Nd:YAG laser is used as the excitation source. A TRIAX monochromator and CCD detector is used for the spectral recording. The observed fluorescence emission for carbon disulphide is centered at 680 nm; this is assigned as due to the n, p* transition. Aniline also shows a broad fluorescence emission centered at 725 nm, which is due to the p,p* transition. The pulsed laser Raman spectra of some organic compounds are also recorded using the same experimental setup. The calibration of the set up is done using the laser Raman spectra of carbon tetrachloride and carbon disulphide. The observed laser Raman spectra for aniline, o-chloroaniline and m-chlorotoluene show peaks characteristics of the aromatic ring in common and the characteristics peaks due to the substitutuent groups. Some new peaks corresponding to low-lying vibrations of these molecules are also assigned
Alex,A V; Jacob, Philip(Cochin University of Science and Technology, May , 2001)
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Abstract:
Ultrasonic is a good tool to investigate the elastic properties of crystals. It enables one to determine all the elastic constants, Poisson’s ratios, volume compressibility and bulk modulus of crystals from velocity measurements. It also enables one to demonstrate the anisotropy of elastic properties by plotting sections of the surfaces of phase velocity, slowness, group velocity, Young’s modulus and linear compressibility along the a-b, b-c and a-c planes. They also help one to understand more about phonon amplification and help to interpret various phenomena associated with ultrasonic wave propagation, thermal conductivity, phonon transport etc. Study of nonlinear optical crystals is very important from an application point of view. Hundreds of new NLO materials are synthesized to meet the requirements for various applications. Inorganic, organic and organometallic or semiorganic classes of compounds have been studied for several reasons. Semiorganic compounds have some advantages over their inorganic and inorganic counterparts with regard to their mechanical properties. High damage resistance, high melting point, good transparency and non-hygroscopy are some of the basic requirements for a material to be suitable for device fabrication. New NLO materials are being synthesized and investigation of the mechanical and elastic properties of these crystals is very important to test the suitability of these materials for technological applications
Godfrey,Louis; Jacob, Philip(Department of Physics, 1994)
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Abstract:
The thesis investigated the elastic properties and phase transitions in selected mixed sulphate crystals – Lithium Hydrazinium Sulphate [LiN2H2SO4], Lithium Ammonium Sulphate [LiNH4SO4] and Lithium Potassium Sulphate [LiKSO4] – using ultrasonic technique. The pulse echo overlap technique has been used for measuring ultrasonic velocity and its dependence on temperature along different directions with waves of longitudinal and transverse polarizations. Two major numerical techniques and the corresponding computer programs developed as part of present work are presented in this thesis. All the 9 elastic constants of LHS are determined accurately from ultrasonic measurements and applying misorientation correction refines the constants. Ultrasonic measurements are performed in LAS to determine the elastic constants and to study the low temperature phase transitions. Temperature variation studies of elastic constant of LAS are performed for 6 different modes of propagation for heating and cooling at low temperatures. All the 5 independent elastic constants of LPS is determined using ultrasonic measurements. It is concluded that LPS crystal does not undergo a phase transition near this temperature. A comparison of the three crystals studied shows that LPS has maximum number of phase transitions and LHS has the least number. It is interesting to note that LPS has the simplest formula unit among the three. There is considerable scope for the future work on these crystals and others belonging to the sulphate family.
Prabha, C; Dr.Pillai, P R S(Cochin University of Science And Technology, July 24, 2013)
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Abstract:
Underwater target localization and tracking attracts tremendous research interest due to various impediments to the estimation task caused by the noisy ocean environment. This thesis envisages the implementation of a prototype automated system for underwater target localization, tracking and classification using passive listening buoy systems and target identification techniques. An autonomous three buoy system has been developed and field trials have been conducted successfully. Inaccuracies in the localization results, due to changes in the environmental parameters, measurement errors and theoretical approximations are refined using the Kalman filter approach. Simulation studies have been conducted for the tracking of targets with different scenarios even under maneuvering situations. This system can as well be used for classifying the unknown targets by extracting the features of the noise emanations from the targets.
Description:
Department of Electronics, Cochin University of Science and Technology.
Nify, Benny; Dr.Sujatha, C H(Cochin University of Science and Technology, June , 2009)
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Abstract:
The thesis deals with a benchmark study of dissolved and sedimentary sulphur
compounds which play prominent roles in the prevailing redox conditions in the
selected sites of Cochin estuarine system. Sulphur and its analogues play prominent
roles in estuarine biochemical processes. A complete knowledge on the sulphur
involvement in these processes is restricted due to the lacking of data on the organic
sulphur compounds. Sulphate and sulphide in surface and bottom water and
Sulphate, acid volatile sulphide and total sulphur in sediments were studied and
correlated to know their interrelations in determining the redox condition of the
environment. It also characterises the sediments of the sites on the basis of total
organic carbon: total sulphur ratio. The study had attempted to decrease the
concentration levels of sulphur in the sedimentary environment by the application of
a remedial measure. Knowledge of sulphur uptake by plants from prior literatures
has prompted to use phytoremediation for decreasing the sulphur concentration.
Phytoremediation is an emerging technology that uses plants to clean up or remediate
contaminated soil, sludges, sediments, and ground water through contaminant
removal, degradation or containment. The plant selected was wheat grass since
earlier studies have shown that wheat grass is effective in remediating pollutants
particularly trace metals. So reduction in the concentration of selected trace metals
was also focussed.
Description:
Department of Chemical Oceanography, Cochin University of Science and Technology
Radhakrishnan, N; Dr.Meera Bai,M(Cochin University of Science and Technology, November 20, 2003)
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Abstract:
Studies in urban water supply system are few in the state of Kerala.
It is a little researched area. In the case of water pricing a number of studies are
available. In Kerala state, exception to Jacob John’s study on “Economics of
Public Water Supply System”, which is a case study of Trivandrum Water Supply
System in 1997, no exhaustive research work has so far come out in this field.
loreover no indepth research study has come up, so far, relating to household
ater demand analysis and the distribution system of urban piped water supply.
he proposed study is first of its kind, which focuses on the distributional and
Iailability problems of piped water supply in an urban centre in Kerala state.
Hence there is a felt need for enquiring into the sufficiency of
)table water supplied to people in urban areas and the efficiency maintained in
roviding the scarce resource and preventing its misuse by the consumers. It is in
llS backdrop that this study was undertaken and its empirical part was conducted
|Calicut city in the state of Kerala. Study is confined to the water supply system
ithe city of Calicut
Description:
Department of Applied Economics,
Cochin University of Science and Technology