In this paper the design issues of compact genetic microstrip antennas for mobile
applications has been investigated. The antennas designed using Genetic Algorithms
(GA) have an arbitrary shape and occupies less area (compact) compared to the
traditionally designed antenna for the same frequency but with poor performance. An
attempt has been made to improve the performance of the genetic microstrip antenna by
optimizing the ground plane (GP) to have a fish bone like structure. The genetic antenna
with the GP optimized is even better compared to the traditional and the genetic antenna.
Description:
Antennas and Propagation Society International Symposium, 2008. AP-S 2008. IEEE
A compact microstrip multiband antenna on a
modified ground plane which can operate over the bands starting
from 900 MHz to 5.35 GHz which includes the GSM (880-960)
GPS (1568-1592 MHz), DCS (1710-1880 MHz), and PCS (1850-
1990 MHz). UMTS (1920-2170 MHz), IEEE 802.11 b/g (2400-
2484) and WLAN IEEE 802.11a band (5.15-5.35) is reported in
this paper. The overall dimension of the antenna is 33 x 33 mm2
including the top patch with a dimension 22 x 22 mm2. The
experimental results of the antenna are presented in this paper.
The results confirm that the antenna exhibits wide band
characteristics and covers 7 bands of operation
Jayaprakash, P; Dr. Menon, A K(Cochin University of Science And Technology, March 15, 1999)
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Abstract:
A GIS has been designed with limited Functionalities; but with a novel approach in
Aits design. The spatial data model adopted in the design of KBGIS is the unlinked
vector model. Each map entity is encoded separately in vector fonn, without referencing
any of its neighbouring entities. Spatial relations, in other words, are not encoded. This
approach is adequate for routine analysis of geographic data represented on a planar map,
and their display (Pages 105-106). Even though spatial relations are not encoded
explicitly, they can be extracted through the specially designed queries.
This work was undertaken as an experiment to study the feasibility of developing a
GIS using a knowledge base in place of a relational database. The source of input spatial
data was accurate sheet maps that were manually digitised. Each identifiable geographic
primitive was represented as a distinct object, with its spatial properties and attributes
defined. Composite spatial objects, made up of primitive objects, were formulated, based
on production rules defining such compositions. The facts and rules were then organised
into a production system, using OPS5
Description:
Department of Computer Science
School of Computer Science Studies
Cochin University of Science and Technology
Gopikrishna, M; Deepti Das, Krishna; Aanandan,C K; Mohanan, P; Vasudevan, K(Wiley InterScience, April , 2009)
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Abstract:
The design and performance of a stepped slot printed monopole antenna in the ultrawideband is presented in this article. Multiple resonances generated by the stepped slot geometry are matched in the ultrawideband using a modified microstrip feed. The impedance bandwidth (SWR < 2) of the antenna is from 3 to 11 GHz. Radiation patterns are stable and omnidirectional with appreciable gain throughout the band. Performance of the antenna is also analyzed in the time domain, which reveals good pulse handling capabilities. Compact geometry of the antenna allows easy commercial deployment.
Mridula, S; Anju, Pradeep; Mohanan, P(IEEE, August , 2011)
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Abstract:
Electric permittivity and magnetic permeability control electromagnetic wave propagation th rough materials. I n naturally
occu rring materials, these are positive. Artificial materials exhi b iting negative material properties have been reported :
they are referred to as metamaterials. This paper concentrates on a ring-type split-ring resonator (SRR) exhibiting
negative magnetic permeability. The design and synthesis of the SRR using the genetic-algorithm approach is explained
in detail. A user-friendly g raphical user i nterface (G U I ) for an SRR optim izer and estimator using MATLAB TM is also
presented
Description:
IEEE Antennas and Propagation Magazine, Vol. 53, No. 4, August 20 1 1
Mridula, S; Binu, Paul; Mythili, P; Mohanan, P(Wiley Subscription Services, Inc., A Wiley Company, December , 2010)
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Abstract:
A method for simultaneously enhancing the bandwidth
and reducing the size of microstrip antennas (MSAs) using a modified
ground plane (GP) has been proposed with design formulas. A combshaped
truncated GP is used for this purpose. This method provides an
overall compactness up to 85% for proximity-coupled MSAs in the
frequency range of 900 MHz–5.5 GHz with an improvement inbandwidth up to seven times when compared with the conventional ones
Description:
MICROWAVE AND OPTICAL TECHNOLOGY LETTERS / Vol. 52, No. 12, December 2010
Shynu, S V; Gijo,Augustin; Aanandan,C K; Mohanan, P; Vasudevan, K(Progress In Electromagnetics Research, 2006)
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Abstract:
The design of a compact, single feed, dual frequency
dual polarized and electronically reconfigurable microstrip antenna is
presented in this paper. A square patch loaded with a hexagonal slot
having extended slot arms constitutes the fundamental structure of
the antenna. The tuning of the two resonant frequencies is realized by
varying the effective electrical length of the slot arms by embedding
varactor diodes across the slots. A high tuning range of 34.43%
(1.037–1.394 GHz) and 9.27% (1.359–1.485 GHz) is achieved for the
two operating frequencies respectively, when the bias voltage is varied
from 0 to −30 V. The salient feature of this design is that it uses no
matching networks even though the resonant frequencies are tuned in
a wide range with good matching below −10 dB. The antenna has an
added advantage of size reduction up to 80.11% and 65.69% for the two
operating frequencies compared to conventional rectangular patches.
Prakash,P N; Dr.Ramaiah,D(National Institute for Interdisciplinary Science and Technology,CSIR, December , 2008)
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Abstract:
Development of organic molecules that exhibit selective
interactions with different biomolecules has immense significance
in biochemical and medicinal applications. In this context, our main
objective has been to design a few novel functionaIized molecules
that can selectively bind and recognize nucleotides and DNA in the aqueous medium through non-covalent interactions. Our strategy
was to design novel cycIophane receptor systems based on the
anthracene chromophore linked through different bridging moieties
and spacer groups. It was proposed that such systems would have a
rigid structure with well defined cavity, wherein the aromatic
chromophore can undergo pi-stacking interactions with the guest
molecules. The viologen and imidazolium moieties have been
chosen as bridging units, since such groups, can in principle, could
enhance the solubility of these derivatives in the aqueous medium
as well as stabilize the inclusion complexes through electrostatic
interactions.We synthesized a series of water soluble novel functionalized
cyclophanes and have investigated their interactions with
nucleotides, DNA and oligonucIeotides through photophysical.
chiroptical, electrochemical and NMR techniques. Results indicate
that these systems have favorable photophysical properties and
exhibit selective interactions with ATP, GTP and DNA involving
electrostatic. hydrophobic and pi-stacking interactions inside the
cavity and hence can have potential use as probes in biology.
Akhil, K Nair; Dr.Ramaiah,D(Cochin University Of Science And Technology, October 3, 2013)
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Abstract:
Design and study of molecular receptors capable of mimicking
natural processes has found applications in basic research as well as in
the development of potentially useful technologies. Of the various
receptors reported, the cyclophanes are known to encapsulate guest
molecules in their cavity utilizing various non–covalent interactions
resulting in significant changes in their optical properties. This unique
property of the cyclophanes has been widely exploited for the
development of selective and sensitive probes for a variety of guest
molecules including complex biomolecules. Further, the incorporation of
metal centres into these systems added new possibilities for designing
receptors such as the metallocyclophanes and transition metal
complexes, which can target a large variety of Lewis basic functional
groups that act as selective synthetic receptors.
The ligands that form complexes with the metal ions, and are
capable of further binding to Lewis-basic substrates through open
coordination sites present in various biomolecules are particularly
important as biomolecular receptors. In this context, we synthesized a
few anthracene and acridine based metal complexes and novel
metallocyclophanes and have investigated their photophysical and
biomolecular recognition properties.
Description:
Photosciences and Photonics
Chemical Sciences and Technology Division
CSIR-National Institute for Interdisciplinary Science and
Technology (CSIR-NIIST), Trivandrum
Babita Roslind, Jose; Dr.Mythili, P(Cochin University of Science & Technology, January , 2010)
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Abstract:
Analog-to digital Converters (ADC) have an important impact on the overall performance of signal processing system. This research is to explore efficient techniques for the design of sigma-delta ADC,specially for multi-standard wireless tranceivers. In particular, the aim is to develop novel models and algorithms to address this problem and to implement software tools which are avle to assist the designer's decisions in the system-level exploration phase. To this end, this thesis presents a framework of techniques to design sigma-delta analog to digital converters.A2-2-2 reconfigurable sigma-delta modulator is proposed which can meet the design specifications of the three wireless communication standards namely GSM,WCDMA and WLAN. A sigma-delta modulator design tool is developed using the Graphical User Interface Development Environment (GUIDE) In MATLAB.Genetic Algorithm(GA) based search method is introduced to find the optimum value of the scaling coefficients and to maximize the dynamic range in a sigma-delta modulator.
Description:
School of Engineering, Cochin University of Science and Technology
Hatha, A A M; Reema, Singh; Vinay, Narayan; Patricia, McLenachan; Richard, C. Winkworth; Suparna, Mitra; Peter, J. Lockhart; Lorraine, Berry; William, Aalbersberg; Dhana, Rao(Society for Applied Microbiology and Blackwell Publishing Ltd, March 16, 2012)
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Abstract:
Here we investigate the diversity of pathogenic Vibrio
species in marine environments close to Suva, Fiji.
We use four distinct yet complementary analyses –
biochemical testing, phylogenetic analyses, metagenomic
analyses and molecular typing – to provide
some preliminary insights into the diversity of vibrios
in this region. Taken together our analyses confirmed
the presence of nine Vibrio species, including three
of the most important disease-causing vibrios (i.e.
V. cholerae, V. parahaemolyticus and V. vulnificus), in
Fijian marine environments. Furthermore, since toxigenic
V. parahaemolyticus are present on fish for
consumption we suggest these bacteria represent a
potential public health risk. Our results from Illumina
short read sequencing are encouraging in the context
of microbial profiling and biomonitoring. They
suggest this approach may offer an efficient and costeffective
method for studying the dynamics of microbial
diversity in marine environments over time.
Mathew, K T; Anil, Lonappan; Paul, Benzy; Thimothy, V O; Rajasekaran, C; Vinu, Thomas; Joe, Jacob(Wiley InterScience, January , 2009)
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Abstract:
This article reports a new in vitro bile analysis based on
the measurement of the dielectric properties at microwave frequencies.
The measurements were made using rectangular cavity perturbation
technique at the S-band of microwave frequency with the different samples
of bile obtained from healthy persons as well as from patients. It is
observed that an appreciable change in the dielectric properties of patient’s
samples with the normal healthy samples and these measurements
were in good agreement with clinical analysis. These results prove an
alternative in-vitro method of detecting bile abnormalities based on the
measurement of the dielectric properties of bile samples using microwaves
without surgical procedure.
Sumam, Mary Idicula; Geethu, Miriam Jacob(IEEE, 2012)
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Abstract:
In this paper, moving flock patterns are mined from
spatio- temporal datasets by incorporating a clustering
algorithm. A flock is defined as the set of data that
move together for a certain continuous amount of time.
Finding out moving flock patterns using clustering
algorithms is a potential method to find out frequent
patterns of movement in large trajectory datasets. In
this approach, SPatial clusteRing algoRithm thrOugh
sWarm intelligence (SPARROW) is the clustering
algorithm used. The advantage of using SPARROW
algorithm is that it can effectively discover clusters of
widely varying sizes and shapes from large databases.
Variations of the proposed method are addressed and
also the experimental results show that the problem of
scalability and duplicate pattern formation is
addressed. This method also reduces the number of
patterns produced
Description:
2012 International Conference on Data Science & Engineering (ICDSE)