Abstract: For best collaboration, Asynchronous tools and particularly the discussion forums are the most used thanks to their flexibility in terms of time. To convey only the messages that belong to a theme of interest of the tutor in order to help him during his tutoring work, use of a tool for classification of these messages is indispensable. For this we have proposed a semantics classification tool of messages of a discussion forum that is based on LSA (Latent Semantic Analysis), which includes a thesaurus to organize the vocabulary. Benefits offered by formal ontology can overcome the insufficiencies that a thesaurus generates during its use and encourage us then to use it in our semantic classifier. In this work we propose the use of some functionalities that a OWL ontology proposes. We then explain how functionalities like “ObjectProperty", "SubClassOf" and “Datatype" property make our classification more intelligent by way of integrating new terms. New terms found are generated based on the first terms introduced by tutor and semantic relations described by OWL formalism.
Abstract: The paper deals with results of a project “Interoperability Workplaces to Support Teaching of Security Management in a Computer Network". This project is focused on the perspectives and possibilities of "new approaches" to education, training and crisis communication of rescue teams in the Czech Republic. It means that common technologies considering new perspectives are used to educate selected members of crisis management. The main part concentrates on possibilities of application of new technology and computer-aided tools to education and training of Integrated Rescue System teams.This project uses the COST principle for the creation of specialized centers and for all communication between these workplaces.
Abstract: This work concerns the measurements of a Bulk
Acoustic Waves (BAW) emission filter S parameters and compare
with prototypes simulated types. Thanks to HP-ADS, a co-simulation
of filters- characteristics in a digital radio-communication chain is
performed. Four cases of modulation schemes are studied in order to
illustrate the impact of the spectral occupation of the modulated
signal. Results of simulations and co-simulation are given in terms of
Error Vector Measurements to be useful for a general sensibility
analysis of 4th/3rd Generation (G.) emitters (wideband QAM and
OFDM signals)
Abstract: Online discussions are an important component of
both blended and online courses. This paper examines the varieties of
online discussions and the perils, pitfalls and possibilities of this
rather new technological tool for enhanced learning. The discussion
begins with possible perils and pitfalls inherent in this educational
tool and moves to a consideration of the advantages of the varieties
of online discussions feasible for use in teacher education programs.
Abstract: This contribution aims to outline some topics around the process of introduction of compulsory electronic exchange of documents (so called e-Boxes) in public administration. The research was conducted in order to gauge the difference between the expectation of those using internal email and their experience in reality. Both qualitative and quantitative research is employed to lead also to an estimation of the willingness and readiness of government bodies, business units and citizens to adopt new technologies. At the same time the most potent barriers to successful e-communication through the e-Boxes are identified.
Abstract: With the exponentially increasing demand for
wireless communications the capacity of current cellular systems will
soon become incapable of handling the growing traffic. Since radio
frequencies are diminishing natural resources, there seems to be a
fundamental barrier to further capacity increase. The solution can be
found in smart antenna systems.
Smart or adaptive antenna arrays consist of an array of antenna
elements with signal processing capability, that optimize the
radiation and reception of a desired signal, dynamically. Smart
antennas can place nulls in the direction of interferers via adaptive
updating of weights linked to each antenna element. They thus cancel
out most of the co-channel interference resulting in better quality of
reception and lower dropped calls. Smart antennas can also track the
user within a cell via direction of arrival algorithms. This implies that
they are more advantageous than other antenna systems. This paper
focuses on few issues about the smart antennas in mobile radio
networks.
Abstract: Voice over Internet Protocol (VoIP) is a form of voice
communication that uses audio data to transmit voice signals to the
end user. VoIP is one of the most important technologies in the
World of communication. Around, 20 years of research on VoIP,
some problems of VoIP are still remaining. During the past decade
and with growing of wireless technologies, we have seen that many
papers turn their concentration from Wired-LAN to Wireless-LAN.
VoIP over Wireless LAN (WLAN) faces many challenges due to the
loose nature of wireless network. Issues like providing Quality of
Service (QoS) at a good level, dedicating capacity for calls and
having secure calls is more difficult rather than wired LAN.
Therefore VoIP over WLAN (VoWLAN) remains a challenging
research topic. In this paper we consolidate and address major
VoWLAN issues. This research is helpful for those researchers wants
to do research in Voice over IP technology over WLAN network.
Abstract: Advertising today has already become an integral part
of human life as a building block of the consumer community. A
component of the value chain of the media, advertising sector is
struggling increasingly harder to find new methods to reach
consumers. The tendency towards experimental marketing practices
is increasing day by day, especially to divert consumers from the idea
“They are selling something to me.” It is therefore considered a good
idea to investigate the trust in ad media of consumers, who are today
exposed to a great bulk of information from advertising sector.
In this study, the current value of ad media for the young
consumer will be investigated. Data on various ad media reliability
will be comparatively analyzed and young consumers will be traced
by including university students in the study. In this research, which
will be performed on students studying at the Selçuk University
(Turkey) by random sampling method, data will be obtained by
survey technique and evaluated by a statistical analysis.
Abstract: Adapting various sensor devices to communicate
within sensor networks empowers us by providing range of
possibilities. The sensors in sensor networks need to know their
measurable belief of trust for efficient and safe communication. In this
paper, we suggested a trust model using fuzzy logic in sensor network.
Trust is an aggregation of consensus given a set of past interaction
among sensors. We applied our suggested model to sensor networks in
order to show how trust mechanisms are involved in communicating
algorithm to choose the proper path from source to destination.
Abstract: The intention of this lessons is to assess the probability
of optical coherence tomography (OCT) for biometric recognition.
The OCT is the foundation on an optical signal acquisition and
processing method and has the micrometer-resolution. In this study,
we used the porcine skin for verifying the abovementioned means. The
porcine tissue was sound acknowledged for structural and
immunohistochemical similarity with human skin, so it could be
suitable for pre-clinical trial as investigational specimen. For this
reason, it was tattooed by the tattoo machine with the tattoo-pigment.
We detected the pattern of the tattooed skin by the OCT according to
needle speed. The result was consistent with the histology images.
This result showed that the OCT was effective to examine the tattooed
skin section noninvasively. It might be available to identify
morphological changes inside the skin.
Abstract: The objective of this contribution is to study the
performances in terms of bit error rate, of space-time code algorithms
applied to MIMO communication in tunnels. Indeed, the channel
characteristics in a tunnel are quite different than those of urban or
indoor environment, due to the guiding effect of the tunnel.
Therefore, MIMO channel matrices have been measured in a straight
tunnel, in a frequency band around 3GHz. Correlation between array
elements and properties of the MIMO matrices are first studied as a
function of the distance between the transmitter and the receiver.
Then, owing to a software tool simulating the link, predicted values
of bit error rate are given for VLAST, OSTBC and QSTBC
algorithms applied to a MIMO configuration with 2 or 4 array
elements. Results are interpreted from the analysis of the channel
properties.
Abstract: Regarding the multi-media property of internet and the facilities that can be provided for the users, the purpose of this paper is to investigate the users- behavioral patterns and the impact of internet on taboos of marriage. For this purpose a survey technique on the sample size amounted 403 students of governmental guidance schools of city of Mashhad in country of Iran were considered. The results showed, the process of using various internet environments depends on the degree of the users- familiarity with these sites. In order to clarify the effects of the Internet on the taboos of marriage, the non – internet parameters also considered to be controlled. The ttest held among the internet users and non-users, indicated that internet users possess lower taboos of marriage. Extraction of the effects of internet via considering the effects of non-internet parameters, indicate that addiction to the internet, creating a cordial atmosphere, emotional communication, and message attractive factors have significant effects on the family's traditional values.
Abstract: Asynchronous Transfer Mode (ATM) is widely used
in telecommunications systems to send data, video and voice at a
very high speed. In ATM network optimizing the bandwidth through
dynamic routing is an important consideration. Previous research
work shows that traditional optimization heuristics result in suboptimal
solution. In this paper we have explored non-traditional
optimization technique. We propose comparison of two such
algorithms - Genetic Algorithm (GA) and Tabu search (TS), based on
non-traditional Optimization approach, for solving the dynamic
routing problem in ATM networks which in return will optimize the
bandwidth. The optimized bandwidth could mean that some
attractive business applications would become feasible such as high
speed LAN interconnection, teleconferencing etc. We have also
performed a comparative study of the selection mechanisms in GA
and listed the best selection mechanism and a new initialization
technique which improves the efficiency of the GA.
Abstract: On existing online shopping on the web, SSL and
password are usually used to achieve the secure trades. SSL shields
communication from the third party who is not related with the trade,
and indicates that the trader's web site is authenticated by one of the
certification authority. Password certifies a customer as the same
person who has visited the trader's web site before, and protects the
customer's privacy such as what the customer has bought on the site.
However, there is no forensics for the trades in those cased above.
With existing methods, no one can prove what is ordered by
customers, how many products are ordered and even whether
customers have ordered or not. The reason is that the third party has to
guess what were traded with logs that are held by traders and by
customers. The logs can easily be created, deleted and forged since
they are electronically stored. To enhance security with digital
forensics for electronic commerce on the web, I indicate a secure
method with cellular phones.
Abstract: For today-s and future wireless communications applications,
more and more data traffic has to be transmitted with
growing speed and quality demands. The analog front-end of any
mobile device has to cope with very hard specifications regardless
which transmission standard has to be supported. State-of-the-art
analog front-end implementations are reaching the limit of technical
feasibility. For that reason, alternative front-end architectures could
support a continuing development of mobile communications e.g.,
six-port-based front-ends [1], [2].
In this article we propose an analog front-end with high intermediate
frequency and which utilizes additive mixing instead
of multiplicative mixing. The system architecture is presented and
several spurious effects as well as their influence on the system
dimensioning are discussed. Furthermore, several issues concerning
the technical feasibility are provided and some simulation results
are discussed which show the principle functionality of the proposed
superposition heterodyne receiver.
Abstract: The VoIP networks as alternative method to traditional PSTN system has been implemented in a wide variety of structures
with multiple protocols, codecs, software and hardware–based
distributions. The use of cryptographic techniques let the users to have a secure communication, but the calculate throughput as well as the QoS parameters are affected according to the used algorithm. This
paper analyzes the VoIP throughput and the QoS parameters with
different commercial encryption methods. The measurement–based
approach uses lab scenarios to simulate LAN and WAN
environments. Security mechanisms such as TLS, SIAX2, SRTP,
IPSEC and ZRTP are analyzed with μ-LAW and GSM codecs.
Abstract: The increasing importance of FlexRay systems in
automotive domain inspires unceasingly relative researches. One
primary issue among researches is to verify the reliability of FlexRay
systems either from protocol aspect or from system design aspect.
However, research rarely discusses the effect of network topology on
the system reliability. In this paper, we will illustrate how to model
the reliability of FlexRay systems with various network topologies by
a well-known probabilistic reasoning technology, Bayesian Network.
In this illustration, we especially investigate the effectiveness of error
containment built in star topology and fault-tolerant midpoint
synchronization algorithm adopted in FlexRay communication
protocol. Through a FlexRay steer-by-wire case study, the influence
of different topologies on the failure probability of the FlexRay steerby-
wire system is demonstrated. The notable value of this research is
to show that the Bayesian Network inference is a powerful and
feasible method for the reliability assessment of FlexRay systems.
Abstract: In the context of spectrum surveillance, a new method
to recover the code of spread spectrum signal is presented, while the
receiver has no knowledge of the transmitter-s spreading sequence. In
our previous paper, we used Genetic algorithm (GA), to recover
spreading code. Although genetic algorithms (GAs) are well known
for their robustness in solving complex optimization problems, but
nonetheless, by increasing the length of the code, we will often lead
to an unacceptable slow convergence speed. To solve this problem we
introduce Particle Swarm Optimization (PSO) into code estimation in
spread spectrum communication system. In searching process for
code estimation, the PSO algorithm has the merits of rapid
convergence to the global optimum, without being trapped in local
suboptimum, and good robustness to noise. In this paper we describe
how to implement PSO as a component of a searching algorithm in
code estimation. Swarm intelligence boasts a number of advantages
due to the use of mobile agents. Some of them are: Scalability, Fault
tolerance, Adaptation, Speed, Modularity, Autonomy, and
Parallelism. These properties make swarm intelligence very attractive
for spread spectrum code estimation. They also make swarm
intelligence suitable for a variety of other kinds of channels. Our
results compare between swarm-based algorithms and Genetic
algorithms, and also show PSO algorithm performance in code
estimation process.
Abstract: The objective of the paper was to understand the use
of an important element of design, namely color in a Semiotic
system. Semiotics is the study of signs and sign processes, it is often
divided into three branches namely (i) Semantics that deals with the
relation between signs and the things to which they refer to mean, (ii)
Syntactics which addresses the relations among signs in formal
structures and (iii) Pragmatics that relates between signs and its
effects on they have on the people who use them to create a plan for
an object or a system referred to as design. Cubism with its versatility
was the key design tool prevalent across the 20th century. In order to
analyze the user's understanding of interaction and appreciation of
color through the movement of Cubism, an exercise was undertaken
in Dept. of Design, IIT Guwahati. This included tasks to design a
composition using color and sign process to the theme 'Between the
Lines' on a given tessellation where the users relate their work to the
world they live in, which in this case was the college campus of IIT
Guwahati. The findings demonstrate impact of the key design
element color on the principles of visual perception based on image
analysis of specific compositions.
Abstract: This paper illustrates why existing technology
acceptance models are only of limited use for predicting and
explaining the adoption of future information and communication
technologies. It starts with a general overview over technology
adoption processes, and presents several theories for the acceptance
as well as adoption of traditional information technologies. This is
followed by an overview over the recent developments in the area of
information and communication technologies. Based on the
arguments elaborated in these sections, it is shown why the factors
used to predict adoption in existing systems, will not be sufficient for
explaining the adoption of future information and communication
technologies.