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: A major requirement for Grid application developers is ensuring performance and scalability of their applications. Predicting the performance of an application demands understanding its specific features. This paper discusses performance modeling and prediction of multi-agent based simulation (MABS) applications on the Grid. An experiment conducted using a synthetic MABS workload explains the key features to be included in the performance model. The results obtained from the experiment show that the prediction model developed for the synthetic workload can be used as a guideline to understand to estimate the performance characteristics of real world simulation applications.
Abstract: The purposes of this paper are to (1) promote excellence in computer science by suggesting a cohesive innovative approach to fill well documented deficiencies in current computer science education, (2) justify (using the authors' and others anecdotal evidence from both the classroom and the real world) why this approach holds great potential to successfully eliminate the deficiencies, (3) invite other professionals to join the authors in proof of concept research. The authors' experiences, though anecdotal, strongly suggest that a new approach involving visual modeling technologies should allow computer science programs to retain a greater percentage of prospective and declared majors as students become more engaged learners, more successful problem-solvers, and better prepared as programmers. In addition, the graduates of such computer science programs will make greater contributions to the profession as skilled problem-solvers. Instead of wearily rememorizing code as they move to the next course, students will have the problem-solving skills to think and work in more sophisticated and creative ways.
Abstract: Although in sustainable development field, innovative
solutions have been sought worldwide by environmental groups,
academia, governments and companies for many years, recently,
citizens and communities have emerged as a new group and taken
more and more active role in this field. Many scholars call for more
research on the role of community and community innovation in
sustainable development. This paper is to respond to the calls. In
this paper, we first summarize a comprehensive set of innovation
principles. Then, we do a qualitative cross case study by comparing
three community innovation cases in three different areas of sustainable
development according to the innovation principles. Finally,
we summarize the case comparison and discuss the implications
to sustainable development. A unified role model and innovation
distribution map of community innovation are developed to better
understand community innovation in sustainable development..
Abstract: Measurement of competitiveness between countries or regions is an important topic of many economic analysis and scientific papers. In European Union (EU), there is no mainstream approach of competitiveness evaluation and measuring. There are many opinions and methods of measurement and evaluation of competitiveness between states or regions at national and European level. The methods differ in structure of using the indicators of competitiveness and ways of their processing. The aim of the paper is to analyze main sources of competitive potential of the EU Member States with the help of Factor analysis (FA) and to classify the EU Member States to homogeneous units (clusters) according to the similarity of selected indicators of competitiveness factors by Cluster analysis (CA) in reference years 2000 and 2011. The theoretical part of the paper is devoted to the fundamental bases of competitiveness and the methodology of FA and CA methods. The empirical part of the paper deals with the evaluation of competitiveness factors in the EU Member States and cluster comparison of evaluated countries by cluster analysis.
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: Day by day technology increases and problems
associated with this technology also increase. Several researches
were carried out to investigate the deployment of such material safely
in geotechnical engineering in particular and civil engineering in
general. However, different types of waste material have such as
cement duct, fly ash and slag been proven to be suitable in several
applications. In this research cement dust mixed with different
percentages of sand will be used in some civil engineering
application as will be explained later in this paper throughout filed
and laboratory test. The used mixer (waste material with sand) prove
high performance, durability to environmental condition, low cost
and high benefits. At higher cement dust ratio, small cement ratio is
valuable for compressive strength and permeability. Also at small
cement dust ratio higher cement ratio is valuable for compressive
strength.
Abstract: The notion of Next Generation Network (NGN) is
based on the Network Convergence concept which refers to
integration of services (such as IT and communication services) over
IP layer. As the most popular implementation of Service Oriented
Architecture (SOA), Web Services technology is known to be the
base for service integration. In this paper, we present a platform to
deliver communication services as web services. We also implement
a sample service to show the simplicity of making composite web
and communication services using this platform. A Service Logic
Execution Environment (SLEE) is used to implement the
communication services. The proposed architecture is in agreement
with Service Oriented Architecture (SOA) and also can be integrated
to an Enterprise Service Bus to make a base for NGN Service
Delivery Platform (SDP).
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: The distribution, enrichment, and accumulation of zinc
(Zn) in the sediments of Kaohsiung Ocean Disposal Site (KODS),
Taiwan were investigated. Sediment samples from two outer disposal
site stations and nine disposed stations in the KODS were collected per
quarterly in 2009 and characterized for Zn, aluminum, organic matter,
and grain size. Results showed that the mean Zn concentrations varied
from 48 mg/kg to 456 mg/kg. Results from the enrichment factor (EF)
and geo-accumulation index (Igeo) analyses imply that the sediments
collected from the KODS can be characterized between moderate and
moderately severe degree enrichment and between none and none to
medium accumulation of Zn, respectively. However, results of
potential ecological risk index indicate that the sediment has low
ecological potential risk. The EF, Igeo, and Zn concentrations at the
disposed stations were slightly higher than those at outer disposal site.
This indicated that the disposed area centers may be subjected to the
disposal impaction of harbor dredged sediments.
Abstract: Artifact rejection plays a key role in many signal processing applications. The artifacts are disturbance that can occur during the signal acquisition and that can alter the analysis of the signals themselves. Our aim is to automatically remove the artifacts, in particular from the Electroencephalographic (EEG) recordings. A technique for the automatic artifact rejection, based on the Independent Component Analysis (ICA) for the artifact extraction and on some high order statistics such as kurtosis and Shannon-s entropy, was proposed some years ago in literature. In this paper we try to enhance this technique proposing a new method based on the Renyi-s entropy. The performance of our method was tested and compared to the performance of the method in literature and the former proved to outperform the latter.
Abstract: The adsorption properties of CO and H2 on iron-based
catalyst with addition of Zr and Ni were investigated using
temperature programmed desorption process. It was found that on the
carburized iron-based catalysts, molecular state and dissociative state
CO existed together. The addition of Zr was preferential for the
molecular state adsorption of CO on iron-based catalyst and the
presence of Ni was beneficial to the dissociative adsorption of CO. On
H2 reduced catalysts, hydrogen mainly adsorbs on the surface iron
sites and surface oxide sites. On CO reduced catalysts, hydrogen
probably existed as the most stable CH and OH species. The addition
of Zr was not benefit to the dissociative adsorption of hydrogen on
iron-based catalyst and the presence of Ni was preferential for the
dissociative adsorption of hydrogen.
Abstract: The inphase/quadrature (I/Q) amplitude and phase
imbalance effects are studied in coherent optical orthogonal
frequency division multiplexing (CO-OFDM) systems. An analytical
model for the I/Q imbalance is developed and supported by
simulation results. The results indicate that the I/Q imbalance degrades the BER performance considerably.
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: augmented reality is a technique used to insert virtual objects in real scenes. One of the most used libraries in the area is the ARToolkit library. It is based on the recognition of the markers that are in the form of squares with a pattern inside. This pattern which is mostly textual is source of confusing. In this paper, we present the results of a classification of Latin characters as a pattern on the ARToolkit markers to know the most distinguishable among them.
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: Results are presented from a combined experimental
and modeling study undertaken to understand the effect of fuel spray
angle on soot production in turbulent liquid spray flames. The
experimental work was conducted in a cylindrical laboratory furnace
at fuel spray cone angle of 30º, 45º and 60º. Soot concentrations
inside the combustor are measured by filter paper technique. The soot
concentration is modeled by using the soot particle number density
and the mass density based acetylene concentrations. Soot oxidation
occurred by both hydroxide radicals and oxygen molecules. The
comparison of calculated results against experimental measurements
shows good agreement. Both the numerical and experimental results
show that the peak value of soot and its location in the furnace
depend on fuel spray cone angle. An increase in spray angle enhances
the evaporating rate and peak temperature near the nozzle. Although
peak soot concentration increase with enhance of fuel spray angle but
soot emission from the furnace decreases.
Abstract: Generally, administrative systems in an academic
environment are disjoint and support independent queries. The
objective in this work is to semantically connect these independent
systems to provide support to queries run on the integrated platform.
The proposed framework, by enriching educational material in the
legacy systems, provides a value-added semantics layer where
activities such as annotation, query and reasoning can be carried out
to support management requirements. We discuss the development of
this ontology framework with a case study of UAE University
program administration to show how semantic web technologies can
be used by administration to develop student profiles for better
academic program management.
Abstract: This paper proposes a “soft systems" approach to
domain-driven design of computer-based information systems. We
propose a systemic framework combining techniques from Soft
Systems Methodology (SSM), the Unified Modelling Language
(UML), and an implementation pattern known as “Naked Objects".
We have used this framework in action research projects that have
involved the investigation and modelling of business processes using
object-oriented domain models and the implementation of software
systems based on those domain models. Within the proposed
framework, Soft Systems Methodology (SSM) is used as a guiding
methodology to explore the problem situation and to generate a
ubiquitous language (soft language) which can be used as the basis
for developing an object-oriented domain model. The domain model
is further developed using techniques based on the UML and is
implemented in software following the “Naked Objects"
implementation pattern. We argue that there are advantages from
combining and using techniques from different methodologies in this
way.
The proposed systemic framework is overviewed and justified as
multimethodologyusing Mingers multimethodology ideas.
This multimethodology approach is being evaluated through a
series of action research projects based on real-world case studies. A
Peer-Tutoring case study is presented here as a sample of the
framework evaluation process
Abstract: The purpose of this study was to develop a “teachers’
self-efficacy scale for high school physical education teachers
(TSES-HSPET)” in Taiwan. This scale is based on the self-efficacy
theory of Bandura [1], [2]. This study used exploratory and
confirmatory factor analyses to test the reliability and validity. The
participants were high school physical education teachers in Taiwan.
Both stratified random sampling and cluster sampling were used to
sample participants for the study. 350 teachers were sampled in the
first stage and 234 valid scales (male 133, female 101) returned.
During the second stage, 350 teachers were sampled and 257 valid
scales (male 143, female 110, 4 did not indicate gender) returned. The
exploratory factor analysis was used in the first stage, and it got
60.77% of total variance for construct validity. The Cronbach’s alpha
coefficient of internal consistency was 0.91 for sumscale, and
subscales were 0.84 and 0.90. In the second stage, confirmatory factor
analysis was used to test construct validity. The result showed that the
fit index could be accepted (χ2 (75) =167.94, p