In this paper, we propose a multispectral analysis system using wavelet based Principal Component Analysis (PCA), to improve the brain tissue classification from MRI images. Global transforms like PCA often neglects significant small abnormality details, while dealing with a massive amount of multispectral data. In order to resolve this issue, input dataset is expanded by detail coefficients from multisignal wavelet analysis. Then, PCA is applied on the new dataset to perform feature analysis. Finally, an unsupervised classification with Fuzzy C-Means clustering algorithm is used to measure the improvement in reproducibility and accuracy of the results. A detailed comparative analysis of classified tissues with those from conventional PCA is also carried out. Proposed method yielded good improvement in classification of small abnormalities with high sensitivity/accuracy values, 98.9/98.3, for clinical analysis. Experimental results from synthetic and clinical data recommend the new method as a promising approach in brain tissue analysis.
Description:
I.J. Image, Graphics and Signal Processing, 2013, 8, 29-36
Raveendranath, U; Bijukumar, S; Mathew, K T(IEEE, December , 2000)
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Abstract:
A novel cavity perturbation technique using coaxial cavity resonators for the measurement of complex permittivity of liquids is presented. The method employs two types of resonators (Resonator I and Resonator II). Resonator I operates in the frequency range 600 MHz-7 GHz and resonator II operates in the frequency range 4 GHz-14 GHz. The introduction of the capillary tube filled with the sample liquid into the coaxial resonator causes shifts in the resonance frequency and loaded Q-factor of the resonator. The shifts in the resonance frequency and loaded Q-factor are used to determine the real and imaginary parts of the complex permittivity of the sample liquid, respectively. Using this technique, the dielectric parameters of water and nitrobenzene are measured. The results are compared with those obtained using other standard methods. The sources of errors are analyzed.
Bijumon, P V; Sreedevi, Menon K; Suma,M N; Sebastian,M T; Mohanan, P(IEE Electronics letters,UK, March 31, 2005)
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Abstract:
The impedance bandwidth of a high permittivity cylindrical dielectric
resonator antenna excited by a micro strip line was significantly
improved by modifying the feed geometry. The 10 dB return loss
bandwidth is enhanced from 12 to 26% without much affecting the
gain and other radiation properties of the antenna. Good agreement
has been observed between the predicted and measured results
Mohanan, P; Bijumon, P V; Menon,S K; Suma,M N; Sebastian,M T(Department of Electronics, March 31, 2005)
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Abstract:
The impedance bandwidth of a high permittivity cylindrical dielectric
resonator antenna excited by a micro strip line was significantly
improved by modifying the feed geometry. The 10 dB return loss
bandwidth is enhanced from 12 to 26% without much affecting the
gain and other radiation properties of the antenna. Good agreement
has been observed between the predicted and measured results
Deepukumar,M; George,J; Aanandan,C K; Mohanan, P; K G Nair(IEE Electronics letters,UK, June 19, 1996)
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Abstract:
A new dual port microstrip antenna geometry for dual frequency
operation is presented. The structure consists of the intersection
of two circles of the same radius with their centres displaced by a
small fraction of the wavelength . This antenna provides wide
impedance bandwidth and excellent isolation between its ports.
The gain of the antenna is comparable to that of a standard
circular microstrip antenna operating at the same resonant
frequency. A theoretical analysis for calculating the resonant
frequencies of the two ports is also presented
Aanandan,C K; Mohanan, P; K G Nair(IEEE Journals/ Transactions (USA), 1990)
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Abstract:
A microstrip antenna with large bandwidth is developed
using a parasitic technique . Compared to the available
wide-baud antennas,the proposed antenna structure is very
compact and gives a lessdistorted radiation pattern with frequency .
An impedance bandwidth,eight times that of a conventional patch
antenna of the same size, Isachieved. The concept of coupled microstrip
line model Is extended fortheoretical interpretation of the impedance loci
Wang,Wel; Sheng,Bing Chen; Shun,Shi Zhong(Microwave and Optical Technology Letters, October 20, 2004)
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Abstract:
A novel slope -strip feeding technique for a microstrip
antenna is presented in order to achieve a broad bandwidth. The experimental
results show that the optimal bandwidth attained is 53.4% for
less than -10-dB return loss
Bybi, P C; Dr.Mohanan, P(Cochin University of Science & Technology, January , 2009)
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Abstract:
The Present thesis deals with the numerical as well as experimental investigations conducted on the resonance and radiation characteristics of Drum shaped monopole antenna, Funnel shaped monopole antenna and the shorted coplanar antenna.An introduction to the over view of antennas, state of the art planar antenna technologies, different feeding techniques and introduction of coplanar waveguides have been discussed.
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Department of Electronics, Cochin University of Science and Technology
The effective organization and utilisation of resources produced by the students, faculty and research scholars
in university departments assume greater significance. Institutional repositories are developed by many institutions
to provide resources and materials that support students in their studies. The present study recognizes
the value of such a repository in the Engineering and Technology discipline in Cochin University of
Science and Technology. The paper explains the need for a digital repository ofproject reports. The authors
present a modelfor digital repository, and the organization.and administration of such a repository. The study
also analyses the various other factors associated with the proposed depository.
Description:
XXV IASLIC Conference I Chennai I 2005 I pp.117-120
Biju Kumar, S; Aanandan,C K; Mathew, K T(John Wiley & Sons, October 5, 2001)
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Abstract:
The detection of buried objects using time-domain freespace
measurements was carried out in the near field. The location of a
hidden object was determined from an analysis of the reflected signal.
This method can be extended to detect any number of objects. Measurements
were carried out in the X- and Ku-bands using ordinary rectangular
pyramidal horn antennas of gain 15 dB. The same antenna was
used as the transmitter and recei er. The experimental results were
compared with simulated results by applying the two-dimensional
finite-difference time-domain(FDTD)method, and agree well with each
other. The dispersi e nature of the dielectric medium was considered for
the simulation.
Chameswary, J; Dr.Sebastian, M T; Dr.Ananthakumar, S(Cochin University of Science and Technology, May , 2014)
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Abstract:
The first chapter of the thesis gives a general introduction about flexible electronics, dielectrics and composites. The recent developments in flexible electronics also discussed in this chapter. The preparation and characterization techniques used for the butyl rubber ceramic composites are given in chapter 2. The synthesis and characterization of butyl rubber filled with low permittivity ceramic composites are described in chapter 3. The chapter 4 deals with the synthesis and characterization of butyl rubber-high permittivity ceramic composites. The effect of high permittivity ceramic fillers such as TiO2, Sr2Ce2Ti5O15 and SrTiO3 on dielectric, thermal and mechanical properties was studied. The present investigation deals with synthesis, characterization and properties of butyl rubber composites with low, high and very high ceramic fillers and also the effect of particle size on dielectric, thermal and mechanical properties of selected composites.
Alice, M J; Dr.Francis,C A(Cochin University of Science and Technology, July , 2004)
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Abstract:
This thesis Entitled Buyer information and brand choice behaviour in markets with asymmetries.The period of transition set in by globalization and liberalization has ensued a onsiderable degree of homogeneity with western societies with respect to quantity and quality of goods and services.The study is aimed at finding out how the buyers adapt to the prevalent complex and dynamic market configuration by taking an archetypical situation of information gathering and brand- choice decision of select household consumer durables.The study was based on a set of 301 sample respondents who were either first time purchasers or repeat purchasers for household use, of the items
under study in the sample area comprising of rural, urban and semi-urban areas. Data were collected using interview schedule and analysis of the same was done with standard statistical computer programs.Buyer confidence as perceived by buyers with respect to information acquisition and brand-choice represents the felt competence to effectively function in the market.In general, lower levels of education, income and occupation showed lower levels of search. The oldest were also low searchers. The repeat purchasers of the product searched less than the first purchasers. The most important source of information was word of mouth or information from others followed by television advertisements. The least important source of information was billboards, displays and similar forms of advertisements.The second factor is characterized by items representing ‘social attributes’ like, use by many others, use by peers, recommendation by significant others and reputation of the brand. The third factor represents ‘susceptibility to incentives and promotions’.
Description:
Department of Applied Economics, Cochin University of Science and Technology
Poulose Jacob,K; Preetha Theresa, Joy(International Journal of Ad hoc, Sensor & Ubiquitous Computing, August 1, 2012)
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Abstract:
Data caching is an important technique in mobile computing environments for improving data
availability and access latencies particularly because these computing environments are characterized
by narrow bandwidth wireless links and frequent disconnections. Cache replacement policy plays a vital
role to improve the performance in a cached mobile environment, since the amount of data stored in a
client cache is small. In this paper we reviewed some of the well known cache replacement policies
proposed for mobile data caches. We made a comparison between these policies after classifying them
based on the criteria used for evicting documents. In addition, this paper suggests some alternative
techniques for cache replacement
Description:
International Journal of Ad hoc, Sensor & Ubiquitous Computing (IJASUC) Vol.3, No.4, August 2012
Vinayakan, R; Dr. George Thomas, K(National Institute for Interdisciplinary Science and Technology,CSIR, May , 2009)
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Abstract:
The overall focus of the thesis involves the synthesis and
characterization of CdSe QDs overcoated with shell materials for various
biological and chemical sensing applications. Second chapter deals with the
synthesis and characterization of CdSe and CdSe/ZnS core shell QDs. The
primary attention of this work is to develop a simple method based on
photoinduced charge transfer to optimize the shell thickness. Synthesis of
water soluble CdSe QDs, their cytotoxicity analysis and investigation of
nonlinear optical properties form the subject of third chapter. Final chapter
deals with development of QD based sensor systems for the selective
detection of biologically and environmentally important analytes from
aqueous media.
Jose, E C; Dr.Sankaranarayanan, K C(Cochin University of Science and Technology, December , 1996)
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Abstract:
This study is focussed on public and private sector
The study is confined to industrial
Public companies in the states of Kerala and Orissa along with companies in India. undertakings only. sector and private sector
private sector companies in other states were studied. Even
though the original plan of 190 companies as the sample
size could not be accomplished, as the responses were very
poor, but data could be collected frmn 6 public and 5
private sector companies in Kerala, 8 public and 8 private
sector companies in Orissa along with 27 private sector
companies in other states totalling to 54 companies. The
number of years of data collected varies from 2 years to 6
years. Factors which are affecting capital expenditures and
hence leading to the performance of private sector compared
to public sector companies are studied. After the study
and analysis, comparisons are made between public sector
and private sector, and suitable recomendations are made
so that public sector industries can also perform equally
well as the private sector industries in India.
Description:
School of Management Studies, Cochin University of Science & Technology
We have investigated the crystallization characteristics of melt compounded nanocomposites of poly(ethylene terephthalate) (PET) and single
walled carbon nanotubes (SWNTs). Differential scanning calorimetry studies showed that SWNTs at weight fractions as low as 0.03 wt% enhance
the rate of crystallization in PET, as the cooling nanocomposite melt crystallizes at a temperature 10 °C higher as compared to neat PET.
Isothermal crystallization studies also revealed that SWNTs significantly accelerate the crystallization process. WAXD showed oriented
crystallization of PET induced by oriented SWNTs in a randomized PET melt, indicating the role of SWNTs as nucleating sites.