Mohanan, P; Dr.Nair, K G(Cochin University of Science And Technology, March , 1985)
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Abstract:
The flange technique, suggested by Reynolds72
is simple technique to improve antenna characteristics.
Using flange technique we can trim the antenna
characteristic by suitably adjusting the flange parameters75.
Later corrugated flanges87 are used for beam shaping. The
important parameters of the corrugated flanges are (a) flange
angle, (b) flange width, (c) flange position, (d) conductivity
of the flange, (e) amplitude excitation of the flange
elements, (f) period of corrugation etc. Compared to a
compound horn the flange technique offers great convenience
in trimming antenna characteristics.
Horns are commonly used as a feed in radar and
satellite communications. A large number of work had been
done to improve the characteristics of horn antennas. It is
an established fact that grooved walls on the inner surface
of a horn can improve the antenna characteristics44.
Corrugated comb surface can be used for the circular
polarization98, tilt of polarization99 etc. This suggests
the possibility to combine these two phenomena and to
obtain a resultant beam. This thesis presents the result
of an investigation to study the possibility of controlling
different antenna characteristics like polarization, beam
shaping, matching etc, using corrugated flange techniques.
Description:
Department of physics, Cochin University of Science And Technology
Sunoj, S M; Unnikrishnan Nair, N(Taylor & Francis, August 24, 2002)
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Abstract:
In this paper the class of continuous bivariate distributions that has form-invariant weighted distribution with weight
function w(x1, x2) ¼ xa1
1 xa2
2 is identified. It is shown that the class includes some well known bivariate models.
Bayesian inference on the parameters of the class is considered and it is shown that there exist natural conjugate
priors for the parameters
Sujatha, C H; Anu, Gopinath; Neema, Joseph; Nair, S M(Taylor & Francis, September 14, 2010)
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Abstract:
The distribution of three important dissolved forms of nitrogen, viz. nitrate, nitrite and urea in the surface and bottom
water samples collected from 27 selected hydrographic profiles, in the Arabian Sea, along the west coast of India is
described. Of the three forms, nitrate concentrations were the highest and comparatively higher concentrations were
observed in the bottom water. Decomposition of organic matter resulting in the release of the thermodynamically
stable nitrogen species, i.e. nitrate, may be the major factor resulting in higher nitrate concentrations at these
depths, where the water is also characterized by low values of dissolved oxygen and temperature. The significant
positive correlation between A.O.U. and nitrate of the bottom water samples emphasizes the role of oxidative
decomposition of organic matter which plays an active role in reducing the oxygen concentrations below the
theoretical values since at this depth ( 200 m) the net production is taken to be zero. This is also evidenced by
the negative correlation of nitrate with dissolved oxygen and temperature, for the bottom samples
Description:
Chemistry and Ecology, 2002, Vol. 18(3–4), pp. 233–244
Deepa, Sankar; Dr. Tessamma, Thomas(Cochin University of Science and Technology, August , 2011)
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Abstract:
After skin cancer, breast cancer accounts for the second greatest number of cancer diagnoses in women. Currently the etiologies of breast cancer are unknown, and there is no generally accepted therapy for preventing it. Therefore, the best way to improve the prognosis for breast cancer is early detection and treatment. Computer aided detection systems (CAD) for detecting masses or micro-calcifications in mammograms have already been used and proven to be a potentially powerful tool , so the radiologists are attracted by the effectiveness of clinical application of CAD systems. Fractal geometry is well suited for describing the complex physiological structures that defy the traditional Euclidean geometry, which is based on smooth shapes. The major contribution of this research include the development of
• A new fractal feature to accurately classify mammograms into normal and normal (i)With masses (benign or malignant) (ii) with microcalcifications (benign or malignant)
• A novel fast fractal modeling method to identify the presence of microcalcifications by fractal modeling of mammograms and then subtracting the modeled image from the original mammogram.
The performances of these methods were evaluated using different standard statistical analysis methods. The results obtained indicate that the developed methods are highly beneficial for assisting radiologists in making diagnostic decisions. The mammograms for the study were obtained from the two online databases namely, MIAS (Mammographic Image Analysis Society) and DDSM (Digital Database for Screening Mammography.
Description:
Department of Electronics, Cochin University of Science and Technology
Chandramohanakumar, N; Renjith, K R; Manju, Mary Joseph(Springer, May 7, 2010)
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Abstract:
Phosphorus fractionation was employed
to find the bioavailability of phosphorus and its
seasonal variations in the Panangad region of
Cochin estuary, the largest estuarine system in
the southwest coast of India. Sequential extraction
of the surficial sediments using chelating agents
was taken as a tool for this. Phosphate in the
water column showed seasonal variations, with
high values during the monsoon months, suggesting
external runoff. Sediment texture was found to
be the main factor influencing the spatial distribution
of the geochemical parameters in the study
region. Similarly, total phosphorus also showed
granulometric dependence and it ranged between
319.54 and 2,938.83 μg/g. Calcium-bound fraction
was the main phosphorus pool in the estuary.
Significant spatial variations were observed for
all bioavailable fractions; iron-bound inorganic
phosphorus (5.04–474.24 μg/g), calcium-bound inorganic
phosphorus (11.16–826.09 μg/g), and acidsoluble
organic phosphorus (22.22–365.86 μg/g).
Among the non-bioavailable phosphorus, alkalisoluble
organic fraction was the major one (51.92–
1,002.45 μg/g). Residual organic phosphorus was
K. R. Renjith (B) · N. Chandramohanakumar · M. M. Joseph
Department of Chemical Oceanography, School
of Marine Sciences, Cochin University of Science
and Technology, Kochi 682016, Kerala, India
e-mail: renjithaqua@gmail.com
comparatively smaller fraction (3.25–14.64% of
total). The sandy and muddy stations showed
distinct fractional composition and the speciation
study could endorse the overall geochemical character.
There could be buffering of phosphorus,
suggested by the increase in the percentage
of bioavailable fractions during the lean premonsoon
period, counteracting the decreases in
the external loads. Principal component analysis
was employed to find the possible processes
influencing the speciation of phosphorus in the
study region
A methodology for translating text from English into the Dravidian language, Malayalam using statistical models is discussed in this paper. The translator utilizes a monolingual Malayalam corpus and a bilingual English/Malayalam corpus in the training phase and generates automatically the Malayalam translation of an unseen English sentence. Various techniques to improve the alignment model by incorporating the morphological inputs into the bilingual corpus are discussed. Removing the insignificant alignments from the sentence pairs by this approach has ensured better training results. Pre-processing techniques like suffix separation from the Malayalam corpus and stop word elimination from the bilingual corpus also proved to be effective in producing better alignments. Difficulties in translation process that arise due to the structural difference between the English Malayalam pair is resolved in the decoding phase by applying the order conversion rules. The handcrafted rules designed for the suffix separation process which can be used as a guideline in implementing suffix separation in Malayalam language are also presented in this paper. Experiments conducted on a sample corpus have generated reasonably good Malayalam translations and the results are verified with F measure, BLEU and WER evaluation metrics
Description:
Procedia Technology 00 (2011) 000–000,2nd International Conference on Communication, Computing & Security
In this paper we describe the methodology and the structural design
of a system that translates English into Malayalam using statistical models. A
monolingual Malayalam corpus and a bilingual English/Malayalam corpus are
the main resource in building this Statistical Machine Translator. Training
strategy adopted has been enhanced by PoS tagging which helps to get rid of the
insignificant alignments. Moreover, incorporating units like suffix separator and
the stop word eliminator has proven to be effective in bringing about better
training results. In the decoder, order conversion rules are applied to reduce the
structural difference between the language pair. The quality of statistical
outcome of the decoder is further improved by applying mending rules.
Experiments conducted on a sample corpus have generated reasonably good
Malayalam translations and the results are verified with F measure, BLEU and
WER evaluation metrics
Description:
Proceedings of Fourth International Conference on Information Processing, Bangalore, India
Santhosh Kumar, G(Cochin University of Science And Technology, December 7, 2010)
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Abstract:
Free/Open Source Software (FOSS) concept is
very important in the academic community. The open
philosophy of FOSS is consistent with academic
freedom and the open dissemination of knowledge and
information in academia. FOSS can lower the barriers
to access of ICTs by reducing the cost of the software.
This article discusses the success story of
CUSAT's adoption of Free/Open Source Software
Mridula, S; Sumi, M; Dinesh, R; Nijas, C M; Mohanan, P(SPOLECNOST PRO RADIOELEKTRONICKE INZENYRSTVI, April , 2014)
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Abstract:
A novel compact chipless RFID tag using spurline
resonators is discussed in this paper. The detection of
the tag's ID is using the spectral signature of a spurline
resonator circuit. The tag has a data capacity of 8-bits in
the range 2.38 to 4.04 GHz. The tag consists of a spurline
multiresonating circuit and two cross polarized antennas.
The prototype of the tag is fabricated on a substrate CMET/
LK4.3 of dielectric constant 4.3 and loss tangent
0.0018. The measured results show that group delay response
can also be used to decode the tag’s identity
Chandran,A R; Mathew,T; Aanandan,C K; Mohanan, P; Vasudevan, K(Department of Electronics, September , 2004)
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Abstract:
Electromagnetic scattering behaviour of a superstrate loaded metallo–
dielectric structure based on Sierpinski carpet fractal geometry is
reported. The results indicate that the frequency at which backscattering
is minimum can be tuned by varying the thickness of the superstrate.
A reduction in backscattered power of 44 dB is obtained
simultaneously for both TE and TM polarisations of the incident field.
Marine product export does something pivotal in the fish export economy of Kerala. The post WTO period
has witnessed a strengthening of food safety and quality standards applied on food products in the
developed countries. In the case of the primary importers, like the EU, the US and Japan, market actions
will have far reaching reverberations and implications for the marine product exports from developing
nations. The article focuses on Kerala’s marine product exports that had been targeting the markets of the
EU, the US and Japan, and the concomitant shift in markets owing to the stringent stipulations under the
WTO regime. Despite the overwhelming importance of the EU in the marine product exports of the state,
the pronounced influence of irregular components on the quantity and value of marine product exports to
the EU in the post WTO period raises concern. However, the tendencies of market diversification
validated by the forecast generated for the emerging markets of the SEA, the MEA and others, to an extent,
allay the pressures on the marine product export sector of the state which had hitherto relied heavily on the
markets of the EU, the US and Japan
Ambika, G; Nandakumaran, V M(Current Science, January 25, 1990)
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Abstract:
We discuss how the presence of frustration brings about
irregular behaviour in a pendulum with nonlinear
dissipation. Here frustration arises owing to
particular choice of the dissipation. A preliminary
numerical analysis is presented which indicates the transition
to chaos at low frequencies of the driving force.
Junaid, Bushiri M; Antony, C J; Aatiq, A; Yohannan Panicker, C; Hema, Tresa Varghese; Manojkumar, T K(Elsevier, November 15, 2010)
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Abstract:
FT-Raman and FT-IR spectra of ASnFe(PO4)3 [A=Na2, Ca, Cd] were recorded and analyzed. The bands
were assigned in terms of the vibrational group frequencies of SnO6 octahedral and PO4 tetrahedral. The
spectral analysis shows that the symmetry of corner shared octahedral (SnO6) and the tetrahedral (PO4)
are lowered from their free ion symmetry state. The presence of Fe3+ ions disrupts the S–N–O–S–N chain
in the structure. This causes distortion of SnO6 and PO4 in the structure of all the compounds. Also it is
seen that there are two distinct PO4 tetrahedra of different P–O bond lengths. One of these tetrahedra
is linearly distorted in all the title compounds. The PO4 frequencies and bond lengths are calculated
theoretically and are in agreement with the experimental values. The presence of PO4 polyanion in the
structure can reduce the redox energy and hence reduce the metal oxygen covalency strength in the
structure