Title: |
Elastic and mechanical
properties of glass specimen by ultrasonic method |
Author (s): |
A. N. Kannappan, S.
Thirumaran and R. Palani |
Abstract: |
Ultrasonic velocity and
density measurements in Na2CO3 – ZnO – B2O3
and Na2CO3 – PbO – B2O3
composition glasses have been made at a temperature of 303K. These
measured values are used to evaluate elastic modulii such as
longitudinal, Young’s, bulk and shear, Poisson’s ratio, acoustic
impedance, micro hardness, Debye temperature and thermal expansion
coefficient. The results of these parameters have been discussed in
terms of the structural and physical properties of the prepared glasses. |
|
|
|
Title: |
Statistical inferences in
market research for sustainable development in conference tourism |
Author (s): |
Karagiannis Stephanos |
Abstract: |
The action and the
interventions that are based on the research, especially in our days,
very often create permanent and viable results, in the environment, in
the local society and in the economy. In our proposal the constant
question, is the investigation of other forms of tourism, after the
decrease of the traditional tourism product. Specifically, for concrete
geographic units and regions of our country that face problems of
isolation or even those that not have easy access (e.g. islander or
mountainous tourist regions), serial or declining demographic base,
unfavourable socio-economic structure and low or not developmental
records try to attract alternate forms of tourism, e.g.. Conference
tourism. |
|
|
|
Title: |
Equilibrium and kinetic
studies on biosorption of zinc onto gallus domesticus shell powder |
Author (s): |
G. Kalyani, G. Babu Rao,
B. Vijaya Saradhi and Y. Prasanna Kumar |
Abstract: |
Biosorption is
potentially an attractive technology for treatment of wastewater for
retaining heavy metals from dilute solutions. Studies carried through
the environmental biotechnology have shown that many biosorbents present
in the nature have great capacity for removal of heavy metals. The paper
presents the results of studies carried out on sorption of zinc ions
from aqueous solutions by Gallus Domesticus shell powder as a low-cost
sorbent. It was found that crushed Gallus Domesticus shell posse’s
relatively high sorption capacity, when comparing with other sorbents
that was evaluated as 46.05 mg/g. The biosorption experiments were
performed under various conditions such as different initial
concentrations, pH, biosorbent concentration and biosorbent particle
size. It was found that the equilibrium of the process was reached after
60 min. About 0.1g of Gallus Domesticus shell powder was found to be
enough to remove 86.50% of zinc for 20 mg/l of metal ion concentration
from 30 ml aqueous solution. The optimum pH value was found to be 6. The
pseudo first order and pseudo second order kinetic models were used to
describe the kinetic data. The dynamic data fitted with the pseudo
second order kinetic model for zinc. The experimental equilibrium data
were adjusted by the biosorption isotherms from Langmuir, Freundlich,
Redlich & Peterson and Temkin models, and their equilibrium parameters
were determined. The best-adjusted model to the experimental equilibrium
data for eggshell powder was the Freundlich model followed by Langmuir
model. |
|
|
|
Title: |
Quantification of runoff,
soil loss and silt deposition in agricultural watershed |
Author (s): |
S. B. Jadhav, S. R.
Kalbande and S. D. Vikhe |
Abstract: |
Watershed development
programme has been implemented at Wagarwadi in Aundha Tq. of Hingoli
district. The various soil and water conservation measures adopted are
nala bunding, gully control structures, cement plug, loose boulder dams
etc. The total runoff of 142.4, 206.0 and 193.0 mm received during the
year 1997-98, 1998-99 and 1999-2000, respectively. The average sediment
concentration of 4.33, 1.41 and 1.06 gm/liter was observed in the year
1997-98, 1998-99 and 1999-2000, respectively. It is also seen that
1622.575, 1327.58 and 942.56 tones of soil is found to be deposited at
different structures. Due to adoption of soil and water conservation
programme, the silt has been deposited in the watershed itself rather
than to transport from the watershed. |
|
|
|
Title: |
Genetic algorithm applied
to fractal image compression |
Author (s): |
Y. Chakrapani and K.
Soundera Rajan |
Abstract: |
In this paper the
technique of Genetic Algorithm (GA) is applied for Fractal Image
Compression (FIC). With the help of this evolutionary algorithm effort
is made to reduce the search complexity of matching between range block
and domain block. One of the image compression techniques in the spatial
domain is Fractal Image Compression but the main drawback of FIC is that
it involves more computational time due to global search. In order to
improve the computational time and also the acceptable quality of the
decoded image, Genetic algorithm is proposed. Experimental results show
that the Genetic Algorithm is a better method than the traditional
exhaustive search method. |
|
|
|
Title: |
Innovative thinning and
gradient algorithm for binary and grey tone images using first in first
out linear data structure |
Author (s): |
R. M. Noorullah and A.
Damodaram |
Abstract: |
Homotopic Thinning
algorithms have long been investigated in pattern recognition and image
analysis. However, they are order dependent in the sense that the output
depends upon the order used for processing the image pixels as well as
the order in which homotopic structuring elements are applied for
algorithms based on sequential homotopic thinning. In the present study
an algorithm will be proposed to tackle the disadvantage by introducing
an effective notion for order independent homotopic thinning by using
First in First out Linear Data Structure. A critical study will be made
for analyzing the algorithms by considering appropriate anchor points
for skeletonization and by homotopic marking. |
|
|
|
Title: |
Resistance of fly ash
based geopolymer mortars in sulfuric acid |
Author (s): |
Suresh Thokchom, Partha
Ghosh and Somnath Ghosh |
Abstract: |
The present paper
reports the experimental results of a study conducted to assess the
resistance of fly ash based geopolymer mortar specimens in sulfuric
acid. The program consisted immersion of geopolymer mortar samples
having percentage Na2O ranging from 5-8% of fly ash in a 10%
sulfuric acid solution up to a period of 18 weeks and evaluation of its
resistance in terms of visual appearance, residual alkalinity, changes
in weight and compressive strength at regular intervals. Visual
inspection of geopolymer mortar samples did not reveal any recognizable
change in colour and remained structurally intact though the exposed
surface turned slightly softer. Through Optical microscope, corroded
surface could be seen which increased with time of exposure. After
exposure in the acid solution for 18 weeks, the geopolymer samples
almost lost its alkalinity and showed very low weight loss in the range
from 0.41% to 1.23% of initial weight. Loss of weight was found higher
for specimen with higher percent of Na2O. Compressive
strength loss at the end of test was 52% for specimen with 5% Na2O
and 28% for specimens with 8% Na2O. Results obtained in the
present study indicate that geopolymers are highly resistant to sulfuric
acid. |
|
|
|
Title: |
Modeling of six-pulse
rectifier operating under supply unbalanced conditions |
Author (s): |
Hussein A. Kazem, B.
Zahawi and D. Giaouris |
Abstract: |
Modeling of the
six-pulse rectifier bridge circuit, operating under practical operating
conditions, when connected to an unbalanced three-phase supply is
presented in this paper. The time domain model takes full account of
system losses and supply impedance on circuit current and voltage
waveforms, allowing for DC current ripple and the changing states of
conduction of the converter devices. The analysis is valid for all types
of loads and converter conduction modes, including mode 3 overlap when
the angle of overlap extends beyond 60° and the number of conducting
devices alternate between 3 and 4. The proposed results are very close
to the simulation results. |
|
|
|
Title: |
Novel space vector based
generalized discontinuous PWM algorithm for induction motor drives |
Author (s): |
K. Sri Gowri, T.
Brahmananda Reddy and Ch. Sai Babu |
Abstract: |
This paper presents a
novel space-vector based Generalized Discontinuous pulse width
modulation (GDPWM) algorithm without angle estimation based on the
concept of imaginary switching times. The conventional space vector
pulse width modulation (CSVPWM) method with equal division of zero state
vectors V0 and V7 is modified. A constant-variable
μ and modulation phase angle δ ranging from 0 to 1 are used to generate
infinite number of modulating waveforms. Also, the classical triangle
comparison approach is replaced by space vector approach. To avoid the
complex coordinate transformations, trigonometric calculations and
sector identification involved in CSVPWM, the concept of imaginary
switching times is utilized. The imaginary switching times proportional
to the reference phase voltages are used to calculate the actual
switching times for reduced complexity and memory required. The proposed
PWM technique results in reduced current ripple over the CSVPWM at high
modulation indices and low switching losses at all modulation indices.
To validate the proposed method, simulation is carried out on V/f
controlled induction motor and the no-load current waveforms at
different modulation indices and frequencies are presented and %THDs is
compared. |
|
|
|
Title: |
Evaluation of cement Nala
plug |
Author (s): |
S. B. Jadhav, S. R.
Kalbande and S. D. Vikhe |
Abstract: |
A field study to
evaluate the cement nala plug in Wagarwadi watershed of Hingoli district
was carried out during 1998-99. Water storage characteristics in the
cement nala plug was studied by monitoring the depth of water storage in
cement plug and length of water spread. The losses from surface water
storage in the form of evaporation and seepage/percolation were
estimated. The effect of seepage on ground water recharge was studied by
monitoring water levels in the observation wells. Utilization of stored
water in the cement nala plug was observed. The full water storage of
cement nala plug was found to be 1725.91m, with the maximum length and
width of spread, 11.3m and 14.0m, respectively with maximum impounding
of water as 3.0m. The maximum evaporation loss and seepage loss from the
cement nala plug was found to be 257.2 m3 and 1634 m3, respectively. The
impounded water in cement nala plug resulted in the increase in water
levels in the observation wells of the influencing area. Due to silting,
the storage capacity of the cement nala plug was reduced by 2.16 percent
in 5 years its construction with silt retention rate of 24.124 tonnes/year. |
|
|
|
Title: |
Isolation of atranorin,
bergenin and goniothalamin from Hopea sangal |
Author (s): |
Jamal A. Nasser, W. A.
Yaacob, Laily B. Din, Bohari M. Yamin and Jalifah Latip |
Abstract: |
A phytochemical
investigation was conducted on Hopea sangal (Dipterocarpaceae).
Three compounds whose names were atranorin, bergenin and goniothalamin
were isolated from the ethyl acetate extract of the stem bark of the
plant. The structures of these compounds were determined by X-ray and
NMR. Studies with the latter involve 1H, 13C and APT spectral data. |
|
|
|
|