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Nature of Dark Matter in the Context of Recent
Experiments and Observations
-- R Sharma, G K Upadhyaya and M Thakre
Nature of dark matter is still a mystery to understand. An intense review of the discovery of dark matter and
the strategies for determination of the nature of dark matter is presented in this paper. It also presents the
comparative graphs of various experiments and theories to understand the nature of dark
matter.
© 2010 IUP. All Rights Reserved.
Interference Mitigation-Based Space Time Equalizers
for MIMO Wireless Communication System
-- Syed A Imam and Vibhav Kumar Sachan
This paper analyzes the performance of space time equalizer in multiple transmitter-multiple receiver
(MIMO) wireless communication system by combining it with Minimum Mean Square Error (MMSE) Equalizer.
A comparison of various space diversity techniques is shown and it is found that 2
´ 2 diversity gives better Bit Error Rate (BER) performance with respect to no diversity, transmit diversity and receiver diversity. It is
also verified that the MMSE equalizer can operate better than other linear and nonlinear equalizers. The
parameters of space time equalizer are optimized according to the MMSE criterion to reduce the effect of noise,
Intersymbol Interference (ISI), and Multi-Access Interference (MAI) while at the same time maintaining
moderate complexity. The system performance is evaluated using the Gaussian approximation. Numerical and
simulation results showed that the MMSE-MIMO exhibited significant performance improvement over the
standard space-time coded system, especially in interference limited conditions.
© 2010 IUP. All Rights Reserved.
Prediction of Solid Waste Generation Using
Self-Organizing Map and Multilayer Perceptron
Neural Networks
-- Ogwueleka Toochukwu Chibueze and Ogwueleka Francisca Nonyelum
Accurate waste generation prediction, necessary for relative waste forecasting is a difficult task due to
the complexity and inherent nonlinearity of waste data.
Self-organizing map (SOM) was used to cluster the communes into three clusters of low, medium and high groups. The six selected variables were
population, dwelling, geographic, economic, education and waste related variables. Multilayer perceptron neural
network was applied to find the best models for the clusters and in predicting the volume of waste generation for
a specific year. The training and testing data were collected in Abuja during the years 2007 to 2008.
The model efficiency and accuracy were measured based on the absolute average error and correlation
coefficient (R2). The model had validation R2 of 0.982 and average error less than 14.1% when compared to
measured data. ANN appears to be a promising tool.
© 2010 IUP. All Rights Reserved.
The Effect of Coupling a Flat Plate Collector on
the Single Slope Basin Solar Still Productivity
-- Jadhav Madhav V
An experimental investigation to study the effect of coupling a flat plate solar collector on the productivity
of simple basin solar stills was carried out. The optimal values of other parameters (water depth, sun
energy, day time wind speed, day time ambient temperature, temperature of basin water and temperature below
glass cover) to enhance the productivity were also studied. A single slope basin solar still made up of
galvanized steel was coupled with a flat plate collector. The average daily out put of simple basin solar still and
coupled solar still, based on data collected for five weeks from March 1, 2009, to April 4, 2009, was found to
be 2.233 L/m2 day and 6.385
L/m2 day, respectively. The maximum hourly distilled water productivity
of simple basin solar still is 0.389
L/m2 and for coupled solar still is 1.150 L/
m2. The average basin water temperature acquired in simple basin solar still is 79.46 °C and in coupled solar still it is 95.25 °C.
The water used for desalination in solar still has TDS 896 ppm, pH 8 and electrical conductivity 1.4 mL
mho/L. After desalination, the distilled water has TDS 0 ppm, pH 6.9, and electrical conductivity 0 mL
mho/L. All other contaminants were absent. The distilled water obtained from the solar still has quality C1-S1
and is better than the other tested water samples.
© 2010 IUP. All Rights Reserved.
Decision Support System for Butter Oil System of
a Dairy Plant at Ndri
-- Sanjay Kajal, P C Tewari and Deepak Kausik
The paper discusses a decision support system for a butter oil unit of a dairy plant at the National
Dairy Research Institute (NDRI). The total plant is divided into many sections like milk marketing section,
condensing and drying section, cheese and butter section, quality control section and packaging section. The plant
comprises various mechanical systems working in series and parallel configuration. Failure and repair rates are
assumed to be constant. The mathematical model of the butter oil unit has been developed using the Markov
Birth-Death process. The differential equations have been developed on the basis of probabilistic approach using
a transition diagram. These equations are further solved using normalizing conditions in order to develop
the steady state availability, which is the measure of performance of a system concerned. The system
performance has been further analyzed with the help of decision matrices. These matrices provide various
availability levels for different combinations of failures and repair rates for various subsystems. Furthermore, the
decision support system has also been developed based on decision matrices of butter oil system of a NDRI plant.
© 2010 IUP. All Rights Reserved.
Leaching of Minerals in Sub-Bituminous Indian Coal
and Characterization of the Products
-- Manoj B, Kunjomana A G and Mansoor Ahmed
This paper reports the demineralization of sub-bituminous coal with ethylenediamine tetraacetic acid
(EDTA), HCl, HF, chloroform and acid mixture. The residual coal from each treatment was analyzed using
Fourier Transform Infrared (FTIR) spectroscopy and Ultimate analysis. FTIR spectrum of raw coal sample was
recorded for enhancing the comparison. The spectrums were found to have similar broad characteristics. It was
evident from the results that amongst the leachants used, Hydrofluoric acid and acid mixtures had significant effect
in removing the mineral matter and oxygenated functional groups.
© 2010 IUP. All Rights Reserved.
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