Sweety, Isaac; Dr.Humayoon,Kabir S(Cochin University of Science and Technology, November 3, 2008)
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Abstract:
This thesis Entitled Internet Utilization and Academic Activities of Faculty Members in the Universities of kerala: an analytical study. Today, scientific research is throwing up new discoveries, inventions and vistas by the hour. We are witnessing a veritable knowledge explosion. It is important for members of university faculty members to keep abreast of it for giving up-t-date information to their students about the new development in the subject of their study. The internet is an invaluable tool for achieving it. Most of the universities have sufficient internet facility, but the accessibility to all the faculty members is not adequate. University Libraries also provides standard supplementary service in the internet area. This study indicates differential level of awareness and utilization of the internet services by the faculty members in the areas of teaching, research and publication. However the overall impression is that the awareness and utilization is inadequate. This point to the urgent need to devise programs and schemes to promote internet utilization among the faculty members. The suggestions indicate the key areas that deserve attention by policy makers and administrators. Thanks to the internet, every new development in every field of study is just a click away for faculty members, research scholars and students.
Description:
Department of Computer Applications, Cochin University of Science and Technology
Malini, K A; Kurian, P; Anantharaman, M R(Elsevier, July , 2003)
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Abstract:
Composite magnetic materials have the unique advantage of property modification for tailoring devices for various
applications. Rubber ferrite composites (RFCs) prepared by incorporating ferrites in rubber matrixes have the advantage of easy
mouldability and flexibility. RFCs containing various loadings of nickel zinc ferrite (NZF) (Ni1 xZnxFe2O4) in a natural rubber
matrix have been prepared. The cure characteristics and the mechanical properties of these composites were evaluated. The
effect of loading on the cure characteristics and tensile properties were also evaluated. It is found that the loading dependence on
the cure time and mechanical properties exhibit an identical pattern.
The Tropospheric Biennial Oscillation (TBO), a major interannual
variation phenomenon in the Indo-Pacific region,
is the result of strong ocean-atmosphere coupling over the
Asian-Australian monsoon area. Along with other meteorological
and oceanographic parameters, the tropical circulation
also exhibits interannual oscillations. Even though the
TBO is the result of strong air–sea interaction, the circulation
cells during TBO years are, as yet, not well understood. In
the present study, an attempt has been made to understand
the interannual variability of the mean meridional circulation
and local monsoon circulation over south Asia in connection
with the TBO. The stream function computed from the zonal
mean meridional wind component of NCEP=NCAR reanalysis
data for the years 1950–2003 is used to represent the
meanmeridional circulation. Mean meridional mass transport
in the topics reverses from a weak monsoon to a strong monsoon
in the presence of ENSO, but in normal TBO yearsmean
transport remains weak across the Northern Hemisphere.
The meridional temperature gradient, which drives the mean
meridional circulation, also shows no reversal during the
normal TBO cycle. The local Hadley circulation over the
monsoon area follows the TBO cycle with anomalous ascent
(descent) in strong (weak) monsoon years. During normal
TBO years, the Equatorial region and Indian monsoon areas
exhibit opposite local Hadley circulation anomalies
Poulose Jacob,K; Preetha Theresa, Joy(IEEE, July 6, 2013)
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Abstract:
Cooperative caching is an attractive solution for
reducing bandwidth demands and network latency in mobile
ad hoc networks. Deploying caches in mobile nodes can reduce
the overall traffic considerably. Cache hits eliminate the need
to contact the data source frequently, which avoids additional
network overhead. In this paper we propose a data discovery
and cache management policy for cooperative caching, which
reduces the caching overhead and delay by reducing the
number of control messages flooded in to the network. A cache
discovery process based on location of neighboring nodes is
developed for this. The cache replacement policy we propose
aims at increasing the cache hit ratio. The simulation results
gives a promising result based on the metrics of studies
Description:
Advanced Infocomm Technology (ICAIT), 2013 6th International Conference on
Thomas Lee, S; Dinesh Kumar, S; Suresh, Kumar P; Radhakrishnan, P; Vallabhan, C P G; Nampoori, V P N(Elsevier, 2003)
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Abstract:
We propose and demonstrate a new technique for evanescent wave chemical sensing by writing long period gratings in a bare multimode plastic clad silica fiber. The sensing length of the present sensor is only 10 mm, but is as sensitive as a conventional unclad evanescent wave sensor having about 100 mm sensing length. The minimum measurable concentration of the sensor reported here is 10 nmol/l and the operating range is more than 4 orders of magnitude. Moreover, the detection is carried out in two independent detection configurations viz., bright field detection scheme that detects the core-mode power and dark field detection scheme that detects the cladding mode power. The use of such a double detection scheme definitely enhances the reliability and accuracy of the results. Furthermore, the cladding of the present fiber need not be removed as done in conventional evanescent wave fiber sensors.
In general Indian summer monsoon rainfall did not show any significant trend in all Indian summer monsoon rainfall series, however, it was reported that the ISMR is subjected to spatial trends. This paper made an attempt to bring out long term trends of different intensity classes of summer monsoon rainfall in different regions of Indian subcontinent. The long term trend of seasonal and monthly rainfall were also made using the India Meteorological Department gridded daily rainfall data with a spatial resolution of 1° × 1° latitude-longitude grid for the period from 1st January, 1901 to 31st December, 2003. The summer monsoon rainfall shows an increasing trend in southeast, northwest and northeast regions, whereas decreasing trend in the central and west coastal regions. In monthly scale, July rainfall shows decreasing trend over west coastal and central Indian regions and significant increasing trend over northeast region at 0.1% significant level. During the month August, decreasing trend is observed in the west coastal stations at 10% significant level. In most of the stations, mean daily rainfall shows an increasing trend for low and very high intense rainfall. For the moderate rainfall, the trend is different for different regions. In the central and southern regions the trend of moderate and moderately high classes show increasing trend. And for the high and very high intensity classes, the trend is decreasing significantly. In the northeastern regions, above 10 mm/day rainfall shows significantly increasing trend with 0.1% significant level.
Girijavallabhan, C P; Radhakrishnan, P; Nampoori, V P N; Geetha, K; Rajesh, M(Journal of Optics A: Pure and Applied Optics, Institute of Physics Publishing, February 24, 2004)
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Abstract:
We report the position dependent tuning of fluorescence emission from
rhodamine 6G doped polymethylmethacrylate film waveguide using a side
illumination technique. The transmitted fluorescence as a function of the
distance from the point of illumination is measured by translating the
waveguide horizontally across a monochromatic light source. This technique
has been utilized to characterize the optical loss in dye doped waveguides.
We observe that the optical loss coefficients for shorter and longer distances
of propagation through the dye doped waveguide are different. At longer
distance of propagation a decrease in optical loss coefficient is observed
Anupam,Chandran R; Thomaskutty,Mathew; Aanandan,C K; Mohanan, P; Vasudevan, K(Microwave and Optical Technology Letters, February 5, 2004)
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Abstract:
A novel technique for backscattering reduction for both TE
and TM polarisation, employing a metallo-dielectric structure based on
Sierpinski carpet fractal geometry, is reported. A reduction in backscattered
power of --30 dB is obtained for normal incidence in the X-band for the
structure using the third iterated stage of the fractal geometry
Anantharaman, M R; van den Oetelaar, L C A; Helwegen, J H J M; Brongersma, H H; Ross, J R H; Seshan, K; Smits, R H H(Academic Press, July 20, 1995)
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Abstract:
A series of vanadium-niobium oxide catalysts in which the
vanadia content varies between 0.3 and 18mol%was prepared
by coprecipitation. These catalysts were characterized by X-ray
diffraction (XRD), X-ray photoelectron spectroscopy (XPS),
low-energy ion scattering (LEIS), and by catalytic testing in
the oxidative dehydrogenation reaction of propane. The results
of the surface analysis by XPS and LEIS are compared. It is
concluded that the active site on the catalyst surface contains
2.0 ± 0.3 vanadium atoms on average. This can be understood
byassuming the existenceof two or three different sites:isolated
vanadium atoms, pairs of vanadium atoms, or ensembles of
three vanadium atoms. At higher vanadium concentration more
vanadium clusters with a higher activity are at the surface.LEIS
revealed that as the vanadium concentration in the catalyst
increases, vanadium replaces niobium at the surface. At vanadium
concentrations above 8 mol%, new phases such as P-(Nb,
V)20S which are less active because vanadium is present in
isolated sites are formed, while the vanadium surface concentration
shows a slight decrease
Thomas, Baby; Ramachandran, T; Radhakrishnan, P; Nampoori, V P N; Vallabhan, C P G(IOP Publishing, 1991)
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Abstract:
A low inductance, triggered spark gap switch suitable for a high-current fast discharge system has been developed. The details of the design and fabrication of this pressurized spark gap, which uses only commonly available materials are described. A transverse discharge Blumlein-driven N2 laser incorporating this device gives a peak output power of 700 kW with a FWHM of 3 ns and an efficiency of 0.51%, which is remarkably high for a pulsed nitrogen laser system.
Anantharaman, M R; Saravanan, S; Venkitachalam, S; Joseph, Mathai C(IOP Publishing Ltd and Deutsche Physikalische Gesellschaft, June 17, 2004)
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Abstract:
Thermally stable materials with low dielectric constant (k < 3.9)
are being hotly pursued. They are essential as interlayer dielectrics/intermetal
dielectrics in integrated circuit technology, which reduces parasitic capacitance
and decreases the RC time constant. Most of the currently employed materials
are based on silicon. Low k films based on organic polymers are supposed to
be a viable alternative as they are easily processable and can be synthesized
with simpler techniques. It is known that the employment of ac/rf plasma
polymerization yields good quality organic thin films, which are homogenous,
pinhole free and thermally stable. These polymer thin films are potential
candidates for fabricating Schottky devices, storage batteries, LEDs, sensors,
super capacitors and for EMI shielding. Recently, great efforts have been made in
finding alternative methods to prepare low dielectric constant thin films in place
of silicon-based materials. Polyaniline thin films were prepared by employing
an rf plasma polymerization technique. Capacitance, dielectric loss, dielectric
constant and ac conductivity were evaluated in the frequency range 100 Hz–
1 MHz. Capacitance and dielectric loss decrease with increase of frequency and
increase with increase of temperature. This type of behaviour was found to be in
good agreement with an existing model. The ac conductivity was calculated from
the observed dielectric constant and is explained based on the Austin–Mott model
for hopping conduction. These films exhibit low dielectric constant values, which
are stable over a wide range of frequencies and are probable candidates for low k
applications.
Sijikumar,S; Dr.Mohan Kumar, K(Department of Atmospheric Sciences, 2003)
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Abstract:
The main objective of the of present study are to study the intraseasonal variability of LLJ and its relation with convective heating of the atmosphere, to establish whether LLJ splits into two branches over the Arabian sea as widely believed, the role of horizonatal wind shear of LLJ in the episodes of intense rainfall events observed over the west coast of India, to perform atmospheric modeling work to test whether small (meso) scale vortices form during intense rainfall events along the west coast; and to study the relation between LLJ and monsoon depression genesis. The results of a study on the evolution of Low Level Jetstream (LLJ) prior to the formation of monsoon depressions are presented. A synoptic model of the temporal evolution of monsoon depression has been produced. There is a systematic temporal evolution of the field of deep convection strength and position of the LLJ axis leading to the genesis of monsoon depression. One of the significant outcomes of the present thesis is that the LLJ plays an important role in the intraseasonal and the interannual variability of Indian monsoon activity. Convection and rainfall are dependent mainly on the cyclonic vorticity in the boundary layer associated with LLJ. Monsoon depression genesis and the episodes of very heavy rainfall along the west coast of India are closely related to the cyclonic shear of the LLJ in the boundary layer and the associated deep convection. Case studies by a mesoscale numerical model (MM5) have shown that the heavy rainfall episodes along the west coast of India are associated with generation of mesoscale cyclonic vortices in the boundary layer.
Moosad, K P B; Abdul Rasheed, T M; Nampoori, V P N; Sathianandan, K(Optical Society of America, 1990)
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Abstract:
Low power optical phase conjugation in polyvinyl alcohol
films embedded with saturable dyes is reported. Phase
conjugate reflectivity achieved is higher than that obtained
in the case of similar gelatin films.
Zinc salts of ethyl, isopropyl, and butyl xanthates are prepared
in the laboratory, and the effect of these xanthates with zinc diethyl
dithiocarbamate (ZDC) on the vulcanization of HAF-filled nitrile butadiene
rubber (NBR) compounds has been studied at different temperatures. The cure
times of these compounds have been compared with that of NBR compounds
containing TMTD/MBTS. The rubber compounds with the three xanthate
accelerators and ZDC are cured at various temperatures from 60 to 150°C.
The sheets are molded and properties such as tensile strength, tear strength,
cross-link density, elongation at break, compression set, abrasion resistance,
flex resistance, etc. have been evaluated. The properties show that zinc salt
of the xanthate/ZDC accelerator system has a positive synergistic effect on the
cure rate and mechanical properties of NBR compounds.