Abstract: Long number multiplications (n ≥ 128-bit) are a
primitive in most cryptosystems. They can be performed better by
using Karatsuba-Ofman technique. This algorithm is easy to
parallelize on workstation network and on distributed memory, and
it-s known as the practical method of choice. Multiplying long
numbers using Karatsuba-Ofman algorithm is fast but is highly
recursive. In this paper, we propose different designs of
implementing Karatsuba-Ofman multiplier. A mixture of sequential
and combinational system design techniques involving pipelining is
applied to our proposed designs. Multiplying large numbers can be
adapted flexibly to time, area and power criteria. Computationally
and occupation constrained in embedded systems such as: smart
cards, mobile phones..., multiplication of finite field elements can be
achieved more efficiently. The proposed designs are compared to
other existing techniques. Mathematical models (Area (n), Delay (n))
of our proposed designs are also elaborated and evaluated on
different FPGAs devices.
Abstract: Stochastic modeling of network traffic is an area of
significant research activity for current and future broadband
communication networks. Multimedia traffic is statistically
characterized by a bursty variable bit rate (VBR) profile. In this
paper, we develop an improved model for uniform activity level
video sources in ATM using a doubly stochastic autoregressive
model driven by an underlying spatial point process. We then
examine a number of burstiness metrics such as the peak-to-average
ratio (PAR), the temporal autocovariance function (ACF) and the
traffic measurements histogram. We found that the former measure is
most suitable for capturing the burstiness of single scene video
traffic. In the last phase of this work, we analyse statistical
multiplexing of several constant scene video sources. This proved,
expectedly, to be advantageous with respect to reducing the
burstiness of the traffic, as long as the sources are statistically
independent. We observed that the burstiness was rapidly
diminishing, with the largest gain occuring when only around 5
sources are multiplexed. The novel model used in this paper for
characterizing uniform activity video was thus found to be an
accurate model.
Abstract: This research simulates one of the natural phenomena,
the ocean wave. Our goal is to be able to simulate the ocean wave at
real-time rate with the water surface interacting with objects. The
wave in this research is calm and smooth caused by the force of the
wind above the ocean surface. In order to make the simulation of the
wave real-time, the implementation of the GPU and the
multithreading techniques are used here. Based on the fact that the
new generation CPUs, for personal computers, have multi cores, they
are useful for the multithread. This technique utilizes more than one
core at a time. This simulation is programmed by C language with
OpenGL. To make the simulation of the wave look more realistic, we
applied an OpenGL technique called cube mapping (environmental
mapping) to make water surface reflective and more realistic.
Abstract: Bode stability analysis based on transmission line
modeling (TLM) for single wall carbon nanotube (SWCNT)
interconnects used in 3D-VLSI circuits is investigated for the first
time. In this analysis, the dependence of the degree of relative
stability for SWCNT interconnects on the geometry of each tube has
been acquired. It is shown that, increasing the length and diameter of
each tube, SWCNT interconnects become more stable.
Abstract: In this paper usefulness of quasi-Newton iteration
procedure in parameters estimation of the conditional variance
equation within BHHH algorithm is presented. Analytical solution of
maximization of the likelihood function using first and second
derivatives is too complex when the variance is time-varying. The
advantage of BHHH algorithm in comparison to the other
optimization algorithms is that requires no third derivatives with
assured convergence. To simplify optimization procedure BHHH
algorithm uses the approximation of the matrix of second derivatives
according to information identity. However, parameters estimation in
a/symmetric GARCH(1,1) model assuming normal distribution of
returns is not that simple, i.e. it is difficult to solve it analytically.
Maximum of the likelihood function can be founded by iteration
procedure until no further increase can be found. Because the
solutions of the numerical optimization are very sensitive to the
initial values, GARCH(1,1) model starting parameters are defined.
The number of iterations can be reduced using starting values close
to the global maximum. Optimization procedure will be illustrated in
framework of modeling volatility on daily basis of the most liquid
stocks on Croatian capital market: Podravka stocks (food industry),
Petrokemija stocks (fertilizer industry) and Ericsson Nikola Tesla
stocks (information-s-communications industry).
Abstract: The customer satisfaction for textile sector carries
great importance like the customer satisfaction for other sectors
carry. Especially, if it is considered that gaining new customers
create four times more costs than protecting existing customers from
leaving, it can be seen that the customer satisfaction plays a great
role for the firms. In this study the affecting independent variables of
customer satisfaction are chosen as brand image, perceived service
quality and perceived product quality. By these independent
variables, it is investigated that if any differences exist in perception
of customer satisfaction according to the Turkish textile consumers in
the view of gender. In data analysis of this research the SPSS
program is used.
Abstract: Mobile marketing through mobile messaging service
has highly impressive growth as it enables e-business firms to
communicate with their customers effectively. Educational
institutions hence start using this service to enhance communication
with their students. Previous studies, however, have limited
understanding of applying mobile messaging service in education.
This study proposes a theoretical model to understand the drivers of
students- intentions to use the university-s mobile messaging service.
The model indicates that social influence, perceived control and
attitudes affect students- intention to use the university-s mobile
messaging service. It also provides five antecedents of students-
attitudes–perceived utility (information utility, entertainment utility,
and social utility), innovativeness, information seeking, transaction
specificity (content specificity, sender specificity, and time
specificity) and privacy concern. The proposed model enables
universities to understand what students concern about the use of a
mobile messaging service in universities and handle the service more
effectively. The paper discusses the model development and
concludes with limitations and implications of the proposed model.
Abstract: In this paper a class of numerical methods to solve linear and nonlinear PDEs and also systems of PDEs is developed. The Differential Transform method associated with the Method of Lines (MoL) is used. The theory for linear problems is extended to the nonlinear case, and a recurrence relation is established. This method can achieve an arbitrary high-order accuracy in time. A variable stepsize algorithm and some numerical results are also presented.
Abstract: This paper proposes a method that discovers time series event patterns from textual data with time information. The patterns are composed of sequences of events and each event is extracted from the textual data, where an event is characteristic content included in the textual data such as a company name, an action, and an impression of a customer. The method introduces 7 types of time constraints based on the analysis of the textual data. The method also evaluates these constraints when the frequency of a time series event pattern is calculated. We can flexibly define the time constraints for interesting combinations of events and can discover valid time series event patterns which satisfy these conditions. The paper applies the method to daily business reports collected by a sales force automation system and verifies its effectiveness through numerical experiments.
Abstract: This study proposes a novel recommender system to
provide the advertisements of context-aware services. Our proposed
model is designed to apply a modified collaborative filtering (CF)
algorithm with regard to the several dimensions for the personalization
of mobile devices – location, time and the user-s needs type. In
particular, we employ a classification rule to understand user-s needs
type using a decision tree algorithm. In addition, we collect primary
data from the mobile phone users and apply them to the proposed
model to validate its effectiveness. Experimental results show that the
proposed system makes more accurate and satisfactory advertisements
than comparative systems.
Abstract: Elastic boundary eigensolution problems are converted
into boundary integral equations by potential theory. The kernels of
the boundary integral equations have both the logarithmic and Hilbert
singularity simultaneously. We present the mechanical quadrature
methods for solving eigensolutions of the boundary integral equations
by dealing with two kinds of singularities at the same time. The methods
possess high accuracy O(h3) and low computing complexity. The
convergence and stability are proved based on Anselone-s collective
compact theory. Bases on the asymptotic error expansion with odd
powers, we can greatly improve the accuracy of the approximation,
and also derive a posteriori error estimate which can be used for
constructing self-adaptive algorithms. The efficiency of the algorithms
are illustrated by numerical examples.
Abstract: Experiments have been carried out at the Latvia
University of Agriculture Department of Food Technology. The aim
of this work was to assess the effect of thermal treatment in flexible
retort pouch packaging on the quality of potatoes’ produce during the
storage time. Samples were evaluated immediately after retort
thermal treatment; and following 1; 2; 3 and 4 storage months at the
ambient temperature of +18±2ºC in vacuum packaging from
polyamide/polyethylene (PA/PE) and aluminum/polyethylene
(Al/PE) film pouches with barrier properties. Experimentally the
quality of the potatoes’ produce in dry butter and mushroom
dressings was characterized by measuring pH, hardness, color,
microbiological properties and sensory evaluation. The sterilization
was effective in protecting the produce from physical, chemical, and
microbial quality degradation. According to the study of obtained
data, it can be argued that the selected product processing technology
and packaging materials could be applied to provide the safety and
security during four-month storage period.
Abstract: This article is an extension and a practical application
approach of Wheeler-s NEBIC theory (Net Enabled Business
Innovation Cycle). NEBIC theory is a new approach in IS research
and can be used for dynamic environment related to new technology.
Firms can follow the market changes rapidly with support of the IT
resources. Flexible firms adapt their market strategies, and respond
more quickly to customers changing behaviors. When every leading
firm in an industry has access to the same IT resources, the way that
these IT resources are managed will determine the competitive
advantages or disadvantages of firm. From Dynamic Capabilities
Perspective and from newly introduced NEBIC theory by Wheeler,
we know that only IT resources cannot deliver customer value but
good configuration of those resources can guarantee customer value
by choosing the right emerging technology, grasping the right
economic opportunities through business innovation and growth. We
found evidences in literature that SOA (Service Oriented
Architecture) is a promising emerging technology which can deliver
the desired economic opportunity through modularity, flexibility and
loose-coupling. SOA can also help firms to connect in network which
can open a new window of opportunity to collaborate in innovation
and right kind of outsourcing. There are many articles and research
reports indicates that failure rate in outsourcing is very high but at the
same time research indicates that successful outsourcing projects
adds tangible and intangible benefits to the service consumer.
Business executives and policy makers in the west should not afraid
of outsourcing but they should choose the right strategy through the
use of emerging technology to significantly reduce the failure rate in
outsourcing.
Abstract: In the queueing theory, it is assumed that customer
arrivals correspond to a Poisson process and service time has the
exponential distribution. Using these assumptions, the behaviour of
the queueing system can be described by means of Markov chains
and it is possible to derive the characteristics of the system. In the
paper, these theoretical approaches are presented on several types of
systems and it is also shown how to compute the characteristics in a
situation when these assumptions are not satisfied
Abstract: In this paper we introduce a novel method for
the characterization of synchronziation and coupling effects
in multivariate time series that can be used for the analysis
of EEG or ECoG signals recorded during epileptic seizures.
The method allows to visualize the spatio-temporal evolution
of synchronization and coupling effects that are characteristic
for epileptic seizures. Similar to other methods proposed for
this purpose our method is based on a regression analysis.
However, a more general definition of the regression together
with an effective channel selection procedure allows to use the
method even for time series that are highly correlated, which
is commonly the case in EEG/ECoG recordings with large
numbers of electrodes. The method was experimentally tested
on ECoG recordings of epileptic seizures from patients with
temporal lobe epilepsies. A comparision with the results from
a independent visual inspection by clinical experts showed
an excellent agreement with the patterns obtained with the
proposed method.
Abstract: Construction delay is unavoidable in developing
countries including Malaysia. It is defined as time overrun or
extension of time for completion of a project. The purpose of the
study is to determine the causes of delay in Malaysian construction
industries based on previous worldwide research. The field survey
conducted includes the experienced developers, consultants and
contractors in Malaysia. 34 causes of the construction delay have
been determined and 24 have been selected using the Rasch model
analysis. The analysis result will be used as the baseline for the next
research to find the causes of delay in the Malaysian construction
industry taking place in Malaysian higher learning institutions.
Abstract: A sequential decision problem, based on the task ofidentifying the species of trees given acoustic echo data collectedfrom them, is considered with well-known stochastic classifiers,including single and mixture Gaussian models. Echoes are processedwith a preprocessing stage based on a model of mammalian cochlearfiltering, using a new discrete low-pass filter characteristic. Stoppingtime performance of the sequential decision process is evaluated andcompared. It is observed that the new low pass filter processingresults in faster sequential decisions.
Abstract: In this paper, a new proposed system for Persian
printed numeral characters recognition with emphasis on
representation and recognition stages is introduced. For the first time,
in Persian optical character recognition, geometrical central moments
as character image descriptor and fuzzy min-max neural network for
Persian numeral character recognition has been used. Set of different
experiments on binary images of regular, translated, rotated and
scaled Persian numeral characters has been done and variety of
results has been presented. The best result was 99.16% correct
recognition demonstrating geometrical central moments and fuzzy
min-max neural network are adequate for Persian printed numeral
character recognition.
Abstract: Vernonia divergens Benth., commonly known as
“Insulin Plant” (Fam: Asteraceae) is a potent sugar killer. Locally the
leaves of the plant, boiled in water are successfully administered to a
large number of diabetic patients. The present study evaluates the
putative anti-diabetic ingredients, isolated from the in vivo and in
vitro grown plantlets of V. divergens for their antimicrobial and
anticancer activities. Sterilized explants of nodal segments were
cultured on MS (Musashige and Skoog, 1962) medium in presence of
different combinations of hormones. Multiple shoots along with
bunch of roots were regenerated at 1mg l-1 BAP and 0.5 mg l-1 NAA.
Micro-plantlets were separated and sub-cultured on the double
strength (2X) of the above combination of hormones leading to
increased length of roots and shoots. These plantlets were
successfully transferred to soil and survived well in nature. The
ethanol extract of plantlets from both in vivo & in vitro sources were
prepared in soxhlet extractor and then concentrated to dryness under
reduced pressure in rotary evaporator. Thus obtainedconcentrated
extracts showed significant inhibitory activity against gram
negative bacteria like Escherichia coli and Pseudomonas
aeruginosa but no inhibition was found against gram positive
bacteria. Further, these ethanol extracts were screened for in vitro
percentage cytotoxicity at different time periods (24 h, 48 h and 72 h)
of different dilutions. The in vivo plant extract inhibited the growth of
EAC mouse cell lines in the range of 65, 66, 78, and 88% at 100, 50,
25 & 12.5μg mL-1 but at 72 h of treatment. In case of the extract of in
vitro origin, the inhibition was found against EAC cell lines even at
48h. During spectrophotometric scanning, the extracts exhibited
different maxima (ʎ) - four peaks in in vitro extracts as against single
in in vivo preparation suggesting the possible change in the nature of
ingredients during micropropagation through tissue culture
techniques.
Abstract: In order to make conventional implicit algorithm to be applicable in large scale parallel computers , an interface prediction and correction of discontinuous finite element method is presented to solve time-dependent neutron transport equations under 2-D cylindrical geometry. Domain decomposition is adopted in the computational domain.The numerical experiments show that our parallel algorithm with explicit prediction and implicit correction has good precision, parallelism and simplicity. Especially, it can reach perfect speedup even on hundreds of processors for large-scale problems.