Rajasree, K; Vidyalal, V; Radhakrishnan, P; Nampoori, V P N; Vallabhan, C P G(American Institute of Physics, August 1, 1993)
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Abstract:
Laser‐induced damage and ablation thresholds of bulk superconducting samples of Bi2(SrCa)xCu3Oy(x=2, 2.2, 2.6, 2.8, 3) and Bi1.6 (Pb)xSr2Ca2Cu3 Oy (x=0, 0.1, 0.2, 0.3, 0.4) for irradiation with a 1.06 μm beam from a Nd‐YAG laser have been determined as a function of x by the pulsed photothermal deflection technique. The threshold values of power density for ablation as well as damage are found to increase with increasing values of x in both systems while in the Pb‐doped system the threshold values decrease above a specific value of x, coinciding with the point at which the Tc also begins to fall.
Bindhu, C V; Harilal, S S; Geetha K, Varier; Issac, Riju C; Nampoori, V P N; Vallabhan, C P G(IOP, 1996)
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Abstract:
The dual-beam thermal lens technique has been found to be very
effective for the measurement of fluorescence quantum yields of dye solutions. The
concentration-dependence of the quantum yield of rhodamine B in methanol is
studied here using this technique. The observed results are in line with the
conclusion that the reduction in the quantum yield in the quenching region is
essentially due to the non-radiative relaxation of the absorbed energy. The thermal
lens has been found to become abberated above 40 mW of pump laser power.
This low value for the upper limit of pump power is due to the fact that the medium
is a resonantly absorbing one.
Vidyalal, V; Rajasree, K; Vallabhan, C P G(World Scientific Publishing Company, 1996)
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Abstract:
A simple experimental set-up is described to measure the electromagnetic shielding property of high Tc superconducting samples. Measurements were performed using HTSC materials in the form of laser ablated thin films, powders and sintered pellets. Samples used were Gd-123 in pure and doped form as well as a few Bi-based superconducting ceramics. For comparison, similar measurements were carried out on metals like aluminium, copper and μ metal. Very effective shielding was observed for HTSC materials compared to the conventional materials mentioned above. However it also depended on the sample types and poor shielding was observed for powdered HTSC material in comparison to thin films prepared by laser ablation.
Cherukodan, Surendran; Humayoon Kabir, S(Cochin University Of Science And Technology, April 7, 2015)
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Abstract:
The assessment of maturity of software is an important area in the general software sector. The field of OSS also applies various models to measure software maturity. However, measuring maturity of OSS being used for several applications in libraries is an area left with no research so far. This study has attempted to fill the research gap. Measuring maturity of software contributes knowledge on its sustainability over the long term. Maturity of software is one of the factors that positively influence adoption. The investigator measured the maturity of DSpace software using Woods and Guliani‟s Open Source Maturity Model-2005. The present study is significant as it addresses the aspects of maturity of OSS for libraries and fills the research gap on the area. In this sense the study opens new avenues to the field of library and information science by providing an additional tool for librarians in the selection and adoption of OSS. Measuring maturity brings in-depth knowledge on an OSS which will contribute towards the perceived usefulness and perceived ease of use as explained in the Technology Acceptance Model theory.
High strength and high performance concrete are being widely used all over the world. Most of the applications of high strength concrete have been found in high rise buildings, long span bridges etc. The potential of rice husk ash as a cement replacement material is well established .Earlier researches showed an improvement in mechanical properties of high strength concrete with finely ground RHA as a partial cement replacement material. A review of literature urges the need for optimizing the replacement level of cement with RHA for improved mechanical properties at optimum water binder ratio. This paper discusses the mechanical properties of RHA- High strength concrete at optimized conditions
Description:
American Journal of Engineering Research (AJER),Volume-3 pp-14-19
A series of short-isora-fiber-reinforced natural
rubber composites were prepared by the incorporation of
fibers of different lengths (6, 10, and 14 mm) at 15 phr loading
and at different concentrations (10, 20, 30, and 40 phr) with a
10 mm fiber length. Mixes were also prepared with 10 mm
long fibers treated with a 5% NaOH solution. The vulcanization
parameters, processability, and stress-strain properties
of these composites were analyzed. Properties such as tensile
strength, tear strength, and tensile modulus were found to be
at maximum for composites containing longitudinally oriented
fibers 10 mm in length. Mixes containing fiber loadings of 30 phr with bonding agent (resorcinol-formaldehyde [RF]
resin) showed mechanical properties superior to all other
composites. Scanning electron microscopy (SEM) studies
were carried out to investigate the fiber surface morphology,
fiber pullout, and fiber-rubber interface. SEM studies showed
that the bonding between the fiber and rubber was improved
with treated fibers and with the use of bonding agent.
Job, Thomas; Ananth, Ramaswamy(American Society of Civil Engineers, May , 2007)
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Abstract:
This paper presents the results from an experimental program and an analytical assessment of the influence of addition of
fibers on mechanical properties of concrete. Models derived based on the regression analysis of 60 test data for various mechanical
properties of steel fiber-reinforced concrete have been presented. The various strength properties studied are cube and cylinder compressive
strength, split tensile strength, modulus of rupture and postcracking performance, modulus of elasticity, Poisson’s ratio, and strain
corresponding to peak compressive stress. The variables considered are grade of concrete, namely, normal strength 35 MPa , moderately
high strength 65 MPa , and high-strength concrete 85 MPa , and the volume fraction of the fiber Vf =0.0, 0.5, 1.0, and 1.5% . The
strength of steel fiber-reinforced concrete predicted using the proposed models have been compared with the test data from the present
study and with various other test data reported in the literature. The proposed model predicted the test data quite accurately. The study
indicates that the fiber matrix interaction contributes significantly to enhancement of mechanical properties caused by the introduction of
fibers, which is at variance with both existing models and formulations based on the law of mixtures
Description:
Journal of
Materials in Civil Engineering, Vol. 19, No. 5, May 1, 2007.
Anantharaman, M R; Veena Gopalan, E; Malini, K A; Sagar, S; Sakthi Kumar, D; Yasuhiko, Yoshida; Al-Omari, I A(IOP Publishing LTD, July 31, 2009)
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Abstract:
Mn1−xZnxFe2O4 nanoparticles (x = 0 to 1) were synthesized by the wet chemical
co-precipitation technique. X-ray diffraction and transmission electron microscopy and high
resolution transmission electron microscopy were effectively utilized to investigate the
different structural parameters. The ac conductivity of nanosized Mn1−xZnxFe2O4 were
investigated as a function of frequency, temperature and composition. The frequency
dependence of ac conductivity is analysed by the power law σ(ω)ac = Bωn which is typical
for charge transport by hopping or tunnelling processes. The temperature dependence of
frequency exponent n was investigated to understand the conduction mechanism in different
compositions. The conduction mechanisms are mainly based on polaron hopping conduction
Joseph, Mathai C; Anantharaman, M R; Venkitachalam, S; Jayalekshmi,S(Elsevier, September , 2002)
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Abstract:
Polyfurfural thin films lying in the thickness range of 1300–2000 A˚ were prepared by ac plasma polymerization technique.
The current–voltage characteristics in symmetric and asymmetric electrode configuration were studied with a view to determining
the dominant conduction mechanism.It was found that the Schottky conduction mechanism is dominant in plasma polymerized
furfural thin films.The predominance of Schottky mechanism was further confirmed based on the thermally stimulated current
measurements.
Dhanya., R; Dr. P. Jayamurthy(Cochin University of Science and Technology, February 22, 2016)
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Abstract:
The incidence of diabetes is rapidly increasing and by 2030 an expected 592 million individuals
are projected to be affected (WHO report). Hyperglycaemic condition is recognized as the causal
link between diabetes and its complications. The chronic hyperglycemia resulting from diabetes
brings about a rise in oxidative stress due to overproduction of reactive oxygen species (ROS) as
a result of glucose auto oxidation and protein glycosylation. Generation of ROS leads to
oxidative damage of the structural components (such as lipids, DNA and proteins) of cells and
potentiate diabetes related complications. Oxidative insult in cells is also created by the
impairment in functioning of endogenous antioxidant enzymes because of their non enzymatic
glycosylation and oxidation. The prolonged exposure of oxidative stress may cause insulin
resistance by triggering an alteration in cellular redox balance. Several lines of evidence suggest
that oxidative stress occurs in diabetes and could have a role in the development of insulin
resistance. The cause and cellular mechanism responsible for this abnormality is not fully
understand despite of intense investigative efforts. However it is unknown whether it is the cause
or consequence of diabetes. Despite strong experimental evidence indicating that oxidative stress
may determine the onset and progression of late-diabetic complications, controversy exists
between the cause and associative relationship between oxidative stress and diabetes mellitus.
Disruption of glucose homeostasis is a characteristic feature of Non-insulin dependent diabetes
mellitus (NIDDM) and is associated with some complications including cardiovascular disease
and renal failure. Glucose transport, the rate limiting step in glucose metabolism, can be activated
in peripheral tissues by two distinct pathways. One stimulated by insulin through IRS-1/PI3K,
Preface
Page 2
the other by muscle contraction/exercise through the activation of AMPK. Both pathways also
increase the phosphorylation and activity of MAPK family components of which p38 MAPK
participates in the full activation of GLUT4.Insulin exerts its biological effect upon binding with the insulin receptor (IR) thereby activating
the downstream signaling that lead to enhanced glucose uptake. In skeletal muscle, it potentiates
glucose transport through PI3K mediated or non-PI3K mediated pathways. Alterations or defects
in its signal transduction pathway was found in diabetic patients associated with decreased levels
of IRb, IRS-1, and PI3K. In the insulin signaling, PI3K is a key molecule and inhibition of PI3K
completely abolish insulin stimulated uptake. Akt or Pkb is an important downstream target of
insulin stimulated glucose transport and metabolism.Impairment in fuel metabolism occurs in obesity, and this impairment is a leading pathogenic
factor in type 2 diabetes. The insulin resistance associated with type 2 diabetes is most profound
at the level of skeletal muscle as this is the primary site of glucose and fatty acid utilization.
Therefore, an understanding of how to activate AMPK in skeletal muscle would offer significant
pharmacologic benefits in the treatment of type 2 diabetes. Metformin and the thiazolidinedione
drugs exert the effects via activation of AMPK. Activation of AMPK occurs in response to
exercise, an activity known to have significant benefit for type 2 diabetics. AMPK serves as
sensor of energy status whose activity is triggered in response to changes in nutritional status in
order to modulate tissue-specific metabolic pathways
Kannan, Balakrishnan; Manoj, Changat; Henry, Martyn Mulder(Econometric Institute Research Papers, October 1, 2007)
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Abstract:
Following the Majority Strategy in graphs, other consensus strategies, namely
Plurality Strategy, Hill Climbing and Steepest Ascent Hill Climbing strategies on
graphs are discussed as methods for the computation of median sets of pro¯les. A
review of algorithms for median computation on median graphs is discussed and
their time complexities are compared. Implementation of the consensus strategies
on median computation in arbitrary graphs is discussed
Description:
Report/Econometric Institute, Erasmus University Rotterdam,EI 2007-34
Devarajan, G; Dr.Sridhar, C S(Cochin University of Science and Technology, January 30, 1987)
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Abstract:
Median filtering is a simple digital non—linear signal
smoothing operation in which median of the samples in a sliding
window replaces the sample at the middle of the window. The
resulting filtered sequence tends to follow polynomial
trends in the original sample sequence. Median filter preserves
signal edges while filtering out impulses. Due to this property,
median filtering is finding applications in many areas of image
and speech processing. Though median filtering is simple to
realise digitally, its properties are not easily analysed with
standard analysis techniques,
Description:
Department of Electronics, Cochin
University of Science and Technology
Kannan, Balakrishnan; Sandi, Klavzar; Manoj, Changat(Elsevier, December 31, 2007)
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Abstract:
The median of a profile = (u1, . . . , uk ) of vertices of a graph G is the set of vertices x that minimize the sum of distances
from x to the vertices of . It is shown that for profiles with diameter the median set can be computed within an isometric
subgraph of G that contains a vertex x of and the r -ball around x, where r > 2 − 1 − 2 /| |. The median index of a graph
and r -joins of graphs are introduced and it is shown that r -joins preserve the property of having a large median index. Consensus
strategies are also briefly discussed on a graph with bounded profiles.
A periphery transversal of a median graph G is introduced as a set of vertices
that meets all the peripheral subgraphs of G. Using this concept, median graphs
with geodetic number 2 are characterized in two ways. They are precisely
the median graphs that contain a periphery transversal of order 2 as well as
the median graphs for which there exists a profile such that the remoteness
function is constant on G. Moreover, an algorithm is presented that decides
in O(mlog n) time whether a given graph G with n vertices and m edges is a
median graph with geodetic number 2. Several additional structural properties
of the remoteness function on hypercubes and median graphs are obtained and
some problems listed
Description:
University of Ljubljana
Institute of Mathematics, Physics and Mechanics
Department of Mathematics
Preprint series, Vol. 46 (2008), 1046
Kannan, Balakrishnan; Ram Kumar, r(Hindawi Publishing Corporation, October 18, 2012)
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Abstract:
A profile is a finite sequence of vertices of a graph. The set of all vertices of the graph which
minimises the sum of the distances to the vertices of the profile is the median of the profile. Any
subset of the vertex set such that it is the median of some profile is called a median set. The number
of median sets of a graph is defined to be the median number of the graph. In this paper, we identify
the median sets of various classes of graphs such as Kp − e, Kp,q forP > 2, and wheel graph and so
forth. The median numbers of these graphs and hypercubes are found out, and an upper bound for
the median number of even cycles is established.We also express the median number of a product
graph in terms of the median number of their factors.
Description:
International Scholarly Research Network
ISRN Discrete Mathematics
Volume 2012, Article ID 583671, 8 pages
doi:10.5402/2012/583671