Abstract: In the present study, a heterogeneous and
homogeneous gas flow dispersion model for simulation and
optimisation of a large-scale catalytic slurry reactor for the direct
synthesis of dimethyl ether (DME) from syngas and CO2, using a
churn-turbulent regime was developed. In the heterogeneous gas flow
model the gas phase was distributed into two bubble phases: small
and large, however in the homogeneous one, the gas phase was
distributed into only one large bubble phase. The results indicated
that the heterogeneous gas flow model was in more agreement with
experimental pilot plant data than the homogeneous one.
Abstract: Using neural network we try to model the unknown function f for given input-output data pairs. The connection strength of each neuron is updated through learning. Repeated simulations of crisp neural network produce different values of weight factors that are directly affected by the change of different parameters. We propose the idea that for each neuron in the network, we can obtain quasi-fuzzy weight sets (QFWS) using repeated simulation of the crisp neural network. Such type of fuzzy weight functions may be applied where we have multivariate crisp input that needs to be adjusted after iterative learning, like claim amount distribution analysis. As real data is subjected to noise and uncertainty, therefore, QFWS may be helpful in the simplification of such complex problems. Secondly, these QFWS provide good initial solution for training of fuzzy neural networks with reduced computational complexity.
Abstract: With the advance in wireless networking, IEEE 802.16 WiMAX technology has been widely deployed for several applications such as “last mile" broadband service, cellular backhaul, and high-speed enterprise connectivity. As a result, military employed WiMAX as a high-speed wireless connection for data-link because of its point to multi-point and non-line-of-sight (NLOS) capability for many years. However, the risk of using WiMAX is a critical factor in some sensitive area of military applications especially in ammunition manufacturing such as solid propellant rocket production. The US DoD policy states that the following certification requirements are met for WiMAX: electromagnetic effects on the environment (E3) and Hazards of Electromagnetic Radiation to Ordnance (HERO). This paper discuses the Recommended Power Densities and Safe Separation Distance (SSD) for HERO on WiMAX systems deployed on solid propellant rocket production. The result of this research found that WiMAX is safe to operate at close proximity distances to the rocket production based on AF Guidance Memorandum immediately changing AFMAN 91-201.
Abstract: HSDPA is a new feature which is introduced in
Release-5 specifications of the 3GPP WCDMA/UTRA standard to
realize higher speed data rate together with lower round-trip times.
Moreover, the HSDPA concept offers outstanding improvement of
packet throughput and also significantly reduces the packet call
transfer delay as compared to Release -99 DSCH. Till now the
HSDPA system uses turbo coding which is the best coding technique
to achieve the Shannon limit. However, the main drawbacks of turbo
coding are high decoding complexity and high latency which makes
it unsuitable for some applications like satellite communications,
since the transmission distance itself introduces latency due to
limited speed of light. Hence in this paper it is proposed to use LDPC
coding in place of Turbo coding for HSDPA system which decreases
the latency and decoding complexity. But LDPC coding increases the
Encoding complexity. Though the complexity of transmitter
increases at NodeB, the End user is at an advantage in terms of
receiver complexity and Bit- error rate. In this paper LDPC Encoder
is implemented using “sparse parity check matrix" H to generate a
codeword at Encoder and “Belief Propagation algorithm "for LDPC
decoding .Simulation results shows that in LDPC coding the BER
suddenly drops as the number of iterations increase with a small
increase in Eb/No. Which is not possible in Turbo coding. Also same
BER was achieved using less number of iterations and hence the
latency and receiver complexity has decreased for LDPC coding.
HSDPA increases the downlink data rate within a cell to a theoretical
maximum of 14Mbps, with 2Mbps on the uplink. The changes that
HSDPA enables includes better quality, more reliable and more
robust data services. In other words, while realistic data rates are
only a few Mbps, the actual quality and number of users achieved
will improve significantly.
Abstract: Using data of listed Croatian firms from the Zagreb
Stock Exchange we analyze the relationship between firm ownership
(ownership concentration and type) and performance (ROA).
Empirical research was conducted for the period 2003-2010, yielding
with the total of 1,430 observations. Empirical findings based on
dynamic panel analysis indicate that ownership concentration
variable - CR4 is negatively related with performance, i.e. listed firms
with dispersed ownership perform better than firms with concentrated
ownership. Also, the research indicated that foreign controlled listed
firms perform better than domestically controlled firms. Majority
state owned firms perform worse than privately held firms but
dummy variable for privately controlled firms was not statistically
significant in the estimated panel model.
Abstract: Proper orthogonal decomposition (POD) is used to reconstruct spatio-temporal data of a fully developed turbulent channel flow with density variation at Reynolds number of 150, based on the friction velocity and the channel half-width, and Prandtl number of 0.71. To apply POD to the fully developed turbulent channel flow with density variation, the flow field (velocities, density, and temperature) is scaled by the corresponding root mean square values (rms) so that the flow field becomes dimensionless. A five-vector POD problem is solved numerically. The reconstructed second-order moments of velocity, temperature, and density from POD eigenfunctions compare favorably to the original Direct Numerical Simulation (DNS) data.
Abstract: Digital watermarking in medical images can ensure
the authenticity and integrity of the image. This design paper reviews
some existing watermarking schemes and proposes a reversible
tamper detection and recovery watermarking scheme. Watermark
data from ROI (Region Of Interest) are stored in RONI (Region Of
Non Interest). The embedded watermark allows tampering detection
and tampered image recovery. The watermark is also reversible and
data compression technique was used to allow higher embedding
capacity.
Abstract: Understanding the cell's large-scale organization is an
interesting task in computational biology. Thus, protein-protein
interactions can reveal important organization and function of the
cell. Here, we investigated the correspondence between protein
interactions and function for the yeast. We obtained the correlations
among the set of proteins. Then these correlations are clustered using
both the hierarchical and biclustering methods. The detailed analyses
of proteins in each cluster were carried out by making use of their
functional annotations. As a result, we found that some functional
classes appear together in almost all biclusters. On the other hand, in
hierarchical clustering, the dominancy of one functional class is
observed. In brief, from interaction data to function, some correlated
results are noticed about the relationship between interaction and
function which might give clues about the organization of the
proteins.
Abstract: In this paper back-propagation artificial neural
network (BPANN) with Levenberg–Marquardt algorithm is
employed to predict the limiting drawing ratio (LDR) of the deep
drawing process. To prepare a training set for BPANN, some finite
element simulations were carried out. die and punch radius, die arc
radius, friction coefficient, thickness, yield strength of sheet and
strain hardening exponent were used as the input data and the LDR
as the specified output used in the training of neural network. As a
result of the specified parameters, the program will be able to
estimate the LDR for any new given condition. Comparing FEM and
BPANN results, an acceptable correlation was found.
Abstract: In image processing and visualization, comparing two
bitmapped images needs to be compared from their pixels by matching
pixel-by-pixel. Consequently, it takes a lot of computational time
while the comparison of two vector-based images is significantly
faster. Sometimes these raster graphics images can be approximately
converted into the vector-based images by various techniques. After
conversion, the problem of comparing two raster graphics images
can be reduced to the problem of comparing vector graphics images.
Hence, the problem of comparing pixel-by-pixel can be reduced to
the problem of polynomial comparisons. In computer aided geometric
design (CAGD), the vector graphics images are the composition of
curves and surfaces. Curves are defined by a sequence of control
points and their polynomials. In this paper, the control points will be
considerably used to compare curves. The same curves after relocated
or rotated are treated to be equivalent while two curves after different
scaled are considered to be similar curves. This paper proposed an
algorithm for comparing the polynomial curves by using the control
points for equivalence and similarity. In addition, the geometric
object-oriented database used to keep the curve information has also
been defined in XML format for further used in curve comparisons.
Abstract: In today-s era of plasma and laser cutting, machines using oxy-acetylene flame are also meritorious due to their simplicity and cost effectiveness. The objective to devise a Computer controlled Oxy-Fuel profile cutting machine arose from the increasing demand for metal cutting with respect to edge quality, circularity and lesser formation of redeposit material. The System has an 8 bit micro controller based embedded system, which assures stipulated time response. A new window based Application software was devised which takes a standard CAD file .DXF as input and converts it into numerical data required for the controller. It uses VB6 as a front end whereas MS-ACCESS and AutoCAD as back end. The system is designed around AT89C51RD2, powerful 8 bit, ISP micro controller from Atmel and is optimized to achieve cost effectiveness and also maintains the required accuracy and reliability for complex shapes. The backbone of the system is a cleverly designed mechanical assembly along with the embedded system resulting in an accuracy of about 10 microns while maintaining perfect linearity in the cut. This results in substantial increase in productivity. The observed results also indicate reduced inter laminar spacing of pearlite with an increase in the hardness of the edge region.
Abstract: The hydrolysis kinetics of polycrystalline lithium hydride (LiH) in argon at various low humidities was measured by gravimetry and Raman spectroscopy with ambient water concentration ranging from 200 to 1200 ppm. The results showed that LiH hydrolysis curve revealed a paralinear shape, which was attributed to two different reaction stages that forming different products as explained by the 'Layer Diffusion Control' model. Based on the model, a novel two-stage rate equation for LiH hydrolysis reactions was developed and used to fit the experimental data for determination of Li2O steady thickness Hs and the ultimate hydrolysis rate vs. The fitted data presented a rise of Hs as ambient water concentration cw increased. However, in spite of the negative effect imposed by Hs increasing, the upward trend of vs remained, which implied that water concentration, rather than Li2O thickness, played a predominant role in LiH hydrolysis kinetics. In addition, the proportional relationship between vsHs and cw predicted by rate equation and confirmed by gravimetric data validated the model in such conditions.
Abstract: Most CT reconstruction system x-ray computed
tomography (CT) is a well established visualization technique in
medicine and nondestructive testing. However, since CT scanning
requires sampling of radiographic projections from different viewing
angles, common CT systems with mechanically moving parts are too
slow for dynamic imaging, for instance of multiphase flows or live
animals. A large number of X-ray projections are needed to
reconstruct CT images, so the collection and calculation of the
projection data consume too much time and harmful for patient. For
the purpose of solving the problem, in this study, we proposed a
method for tomographic reconstruction of a sample from a limited
number of x-ray projections by using linear interpolation method. In
simulation, we presented reconstruction from an experimental x-ray
CT scan of a Aluminum phantom that follows to two steps: X-ray
projections will be interpolated using linear interpolation method and
using it for CT reconstruction based upon Ordered Subsets
Expectation Maximization (OSEM) method.
Abstract: The research study evaluated the performance of
irrigation system by using special scientific tools like Remote
Sensing and GIS technology, so that proper measurements could be
taken for the sustainable agriculture and water management.
Different performance evaluation parameters had been calculated for
the purposed data was gathered from field investigation and different
government and private organizations. According to the calculations,
organic matter ranges from 0.19% (low value) to 0.76% (high value).
In flat irrigation system for wheat yield ranges from 3347.16 to
5260.39 kg/ha, while the total water applied to wheat crop ranges
from 252.94 to 279.19 mm and WUE ranges from 13.07 to 18.37
kg/ha/mm. For rice yield ranges from 3347.47 to 5433.07 kg/ha with
total water supplied to rice crop ranges from 764.71 to 978.15 mm
and WUE ranges from 3.49 to 5.71 kg/ha/mm. Similarly, in raised
bed system wheat yield ranges from 4569.13 to 6008.60 kg/ha, total
water supplied ranges from 158.87 to 185.09 mm and WUE ranges
from 27.20 to 33.54 kg/ha/mm while in rice crop, yield ranges from
5285.04 to 6716.69 kg/ha, total water supplied ranges from 600.72 to
755.06 mm and WUE ranges from 6.41 to 10.05 kg/ha/mm. Almost
51.3% water saving is observed in bed irrigation system as compared
to flat system. Less water supplied to beds is more affective as its
WUE value is higher than flat system where more water is supplied
in both the seasons. Similarly, RWS values show that maximum
water deficit while minimum area is getting adequate water supply.
Greater yield is recorded in bed system as plant per square meter is
more in bed system in comparison of flat system Thus, the integration
of GIS tools to regularly compute performance indices could provide
irrigation managers with the means for managing efficiently the
irrigation system.
Abstract: The purpose of this paper is to present teacher candidates- beliefs about technology integration in their field of study, which is classroom teaching in this case. The study was conducted among the first year students in college of education in Turkey. This study is based on both quantitative and qualitative data. For the quantitative data- Likert scale was used and for the qualitative data pattern matching was employed. The primary findings showed that students defined educational technology as technologies that improve learning with their visual, easily accessible, and productive features. They also believe these technologies could affect their future students- learning positively.
Abstract: The main goal of microarray experiments is to quantify the expression of every object on a slide as precisely as possible, with a further goal of clustering the objects. Recently, many studies have discussed clustering issues involving similar patterns of gene expression. This paper presents an application of fuzzy-type methods for clustering DNA microarray data that can be applied to typical comparisons. Clustering and analyses were performed on microarray and simulated data. The results show that fuzzy-possibility c-means clustering substantially improves the findings obtained by others.
Abstract: This study deals with Computational Fluid Dynamics
(CFD) studies of the interactions between the air flow and louvered
fins which equipped the automotive heat exchangers. 3D numerical
simulation results are obtained by using the ANSYS Fluent 13.0 code
and compared to experimental data. The paper studies the effect of
louver angle and louver pitch geometrical parameters, on overall
thermal hydraulic performances of louvered fins.
The comparison between CFD simulations and experimental data
show that established 3-D CFD model gives a good agreement. The
validation agrees, with about 7% of deviation respectively of friction
and Colburn factors to experimental results. As first, it is found that
the louver angle has a strong influence on the heat transfer rate. Then,
louver angle and louver pitch variation of the louvers and their effects
on thermal hydraulic performances are studied. In addition to this
study, it is shown that the second half of the fin takes has a
significant contribution on pressure drop increase without any
increase in heat transfer.
Abstract: Cameron Highlands is known for upland tourism area
with vast natural wealth, mountainous landscape endowed with rich
diverse species as well as people traditions and cultures. With these
various resources, CH possesses an interesting visual and panorama
that can be offered to the tourist. However this benefit may not be
utilized without obtaining the understanding of existing landscape
structure and visual. Given a limited data, this paper attempts to
classify landscape visual of Cameron Highlands using land use and
contour data. Visual points of view were determined from the given
tourist attraction points in the CH Local Plan 2003-2015. The result
shows landscape visual and structure categories offered in the study
area. The result can be used for further analysis to determine the best
alternative tourist trails for tourism planning and decision making
using readily available data.
Abstract: In this paper, we present a new and effective image indexing technique that extracts features directly from DCT domain. Our proposed approach is an object-based image indexing. For each block of size 8*8 in DCT domain a feature vector is extracted. Then, feature vectors of all blocks of image using a k-means algorithm is clustered into groups. Each cluster represents a special object of the image. Then we select some clusters that have largest members after clustering. The centroids of the selected clusters are taken as image feature vectors and indexed into the database. Also, we propose an approach for using of proposed image indexing method in automatic image classification. Experimental results on a database of 800 images from 8 semantic groups in automatic image classification are reported.
Abstract: Sharing motivations of viral advertisements by
consumers and the impacts of these advertisements on the
perceptions for brand will be questioned in this study. Three
fundamental questions are answered in the study. These are
advertisement watching and sharing motivations of individuals,
criteria of liking viral advertisement and the impact of individual
attitudes for viral advertisement on brand perception respectively.
This study will be carried out via a viral advertisement which was
practiced in Turkey. The data will be collected by survey method and
the sample of the study consists of individuals who experienced the
practice of sample advertisement. Data will be collected by online
survey method and will be analyzed by using SPSS statistical
package program.
Recently traditional advertisement mind have been changing. New
advertising approaches which have significant impacts on consumers
have been argued. Viral advertising is a modernist advertisement
mind which offers significant advantages to brands apart from
traditional advertising channels such as television, radio and
magazines. Viral advertising also known as Electronic Word-of-
Mouth (eWOM) consists of free spread of convincing messages sent
by brands among interpersonal communication. When compared to
the traditional advertising, a more provocative thematic approach is
argued.
The foundation of this approach is to create advertisements that
are worth sharing with others by consumers. When that fact is taken
into consideration, in a manner of speaking it can also be stated that
viral advertising is media engineering.
The content worth sharing makes people being a volunteer
spokesman of a brand and strengthens the emotional bonds among
brand and consumer. Especially for some sectors in countries which
are having traditional advertising channel limitations, viral
advertising creates vital advantages.