Abstract: In this paper, we introduce a novel platform
encryption method, which modify its keys and random number
generators step by step during encryption algorithms. According to
complexity of the proposed algorithm, it was safer than any other
method.
Abstract: An international cooperation between educators in
Australia and the US has led to a reconceptualization of the teaching
of a library science course at Appalachian State University. The
pedagogy of Action Learning coupled with a 3D virtual learning
environment immerses students in a social constructivist learning
space that incorporates and supports interaction and reflection. The
intent of this study was to build a bridge between theory and practice
by providing students with a tool set that promoted personal and
social reflection, and created and scaffolded a community of practice.
Besides, action learning is an educational process whereby the fifty
graduate students experienced their own actions and experience to
improve performance.
Abstract: A complex valued neural network is a neural network, which consists of complex valued input and/or weights and/or thresholds and/or activation functions. Complex-valued neural networks have been widening the scope of applications not only in electronics and informatics, but also in social systems. One of the most important applications of the complex valued neural network is in image and vision processing. In Neural networks, radial basis functions are often used for interpolation in multidimensional space. A Radial Basis function is a function, which has built into it a distance criterion with respect to a centre. Radial basis functions have often been applied in the area of neural networks where they may be used as a replacement for the sigmoid hidden layer transfer characteristic in multi-layer perceptron. This paper aims to present exhaustive results of using RBF units in a complex-valued neural network model that uses the back-propagation algorithm (called 'Complex-BP') for learning. Our experiments results demonstrate the effectiveness of a Radial basis function in a complex valued neural network in image recognition over a real valued neural network. We have studied and stated various observations like effect of learning rates, ranges of the initial weights randomly selected, error functions used and number of iterations for the convergence of error on a neural network model with RBF units. Some inherent properties of this complex back propagation algorithm are also studied and discussed.
Abstract: Molodstov-s soft sets theory was originally proposed
as general mathematical tool for dealing with uncertainty problems. The matrix form has been introduced in soft set and some of its
properties have been discussed. However, the formulation of soft
matrix in group decision making problem only with equal importance
weights of criteria, which does not show the true opinion of decision maker on each criteria. The aim of this paper is to propose a method
for solving group decision making problem incorporating the importance of criteria by using soft matrices in a more objective manner. The weight of each criterion is calculated by using the Analytic Hierarchy Process (AHP) method. An example of house
selection process is given to illustrate the effectiveness of the proposed method.
Abstract: This paper is taken into consideration the problem of cryptanalysis of stream ciphers. There is some attempts need to improve the existing attacks on stream cipher and to make an attempt to distinguish the portions of cipher text obtained by the encryption of plain text in which some parts of the text are random and the rest are non-random. This paper presents a tutorial introduction to symmetric cryptography. The basic information theoretic and computational properties of classic and modern cryptographic systems are presented, followed by an examination of the application of cryptography to the security of VoIP system in computer networks using LFSR algorithm. The implementation program will be developed Java 2. LFSR algorithm is appropriate for the encryption and decryption of online streaming data, e.g. VoIP (voice chatting over IP). This paper is implemented the encryption module of speech signals to cipher text and decryption module of cipher text to speech signals.
Abstract: Polyurethanes (PURs) are very versatile polymeric
materials with a wide range of physical and chemical properties.
PURs have desirable properties such as high abrasion resistance, tear
strength, shock absorption, flexibility and elasticity. Although they
have relatively poor thermal stability, this can be improved by using
treated clay. Polyurethane/clay nanocomposites have been
synthesized from renewable sources. A polyol for the production of
polyurethane by reaction with an isocyanate was obtained by the
synthesis of palm oil-based oleic acid with glycerol. Dodecylbenzene
sulfonic acid (DBSA) was used as catalyst and emulsifier. The
unmodified clay (kunipia-F) was treated with cetyltrimethyl
ammonium bromide (CTAB-mont) and octadodecylamine (ODAmont).
The d-spacing in CTAB-mont and ODA-mont were 1.571 nm
and 1.798 nm respectively and larger than that of the pure-mont
(1.142 nm). The organoclay was completely intercalated in the
polyurethane, as confirmed by a wide angle x-ray diffraction
(WAXD) pattern.
The results showed that adding clay demonstrated better thermal
stability in comparison with the virgin polyurethane. Onset
degradation of pure PU is at 200oC, and is lower than that of the
CTAB-mont PU and ODA-mont PU which takes place at about
318oC and 330oC, respectively. The mechanical properties (including
the dynamic mechanical properties) of pure polyurethane (PU) and
PU/clay nanocomposites, were measured. The modified organoclay
had a remarkably beneficial effect on the strength and elongation at
break of the nanocomposites, which both increased with increasing
clay content with the increase of the tensile strength of more than
214% and 267% by the addition of only 5 wt% of the
montmorillonite CTAB-mont PU and ODA-mont PU, respectively.
Abstract: In this paper, an ultra low power and low jitter 12bit
CMOS digitally controlled oscillator (DCO) design is presented.
Based on a ring oscillator implemented with low power Schmitt
trigger based inverters. Simulation of the proposed DCO using 32nm
CMOS Predictive Transistor Model (PTM) achieves controllable
frequency range of 550MHz~830MHz with a wide linearity and high
resolution. Monte Carlo simulation demonstrates that the time-period
jitter due to random power supply fluctuation is under 31ps and the
power consumption is 0.5677mW at 750MHz with 1.2V power
supply and 0.53-ps resolution. The proposed DCO has a good
robustness to voltage and temperature variations and better linearity
comparing to the conventional design.
Abstract: Nonlinear finite element method and Serendipity eight
nodes element are used for determining of ground surface settlement
due to tunneling. Linear element with elastic behavior is used for
modeling of lining. Modified Generalized plasticity model with nonassociated
flow rule is applied for analysis of a tunnel in Sao Paulo –
Brazil. The tunnel had analyzed by Lades- model with 16 parameters.
In this work modified Generalized Plasticity is used with 10
parameters, also Mohr-Coulomb model is used to analysis the tunnel.
The results show good agreement with observed results of field data
by modified Generalized Plasticity model than other models. The
obtained result by Mohr-Coulomb model shows less settlement than
other model due to excavation.
Abstract: The results obtained after incorporating the competence “creativity" to the subject Technical Drawing of the first course of the Degree in Forestry, Technical University of Madrid, are presented in this study.At first, learning activities which could serve two functions at the same time -developing students- creativity and developing other specific competences of the subject- were considered. Besides, changes in the assessment procedure were made and a method which analyzes two aspects of the assessment of the competence creativity was established. On the one hand, the products are evaluated by analyzing the outcomes obtained by students in the essays suggested and by establishing a parameter to assess the creativity expressed in those essays. On the other, an assessment of the student is directly carried out through a psychometric test which has been previously chosen by the team.Moreover, these results can be applied to similar or could be of general application.
Abstract: Genetic algorithms (GAs) have been widely used for
global optimization problems. The GA performance depends highly
on the choice of the search space for each parameter to be optimized.
Often, this choice is a problem-based experience. The search space
being a set of potential solutions may contain the global optimum
and/or other local optimums. A bad choice of this search space
results in poor solutions. In this paper, our approach consists in
extending the search space boundaries during the GA optimization,
only when it is required. This leads to more diversification of GA
population by new solutions that were not available with fixed search
space boundaries. So, these dynamic search spaces can improve the
GA optimization performances. The proposed approach is applied to
power system stabilizer optimization for multimachine power system
(16-generator and 68-bus). The obtained results are evaluated and
compared with those obtained by ordinary GAs. Eigenvalue analysis
and nonlinear system simulation results show the effectiveness of the
proposed approach to damp out the electromechanical oscillation and
enhance the global system stability.
Abstract: We summarize information that facilitates choosing an ontology language for knowledge intensive applications. This paper is a short version of the ontology language state-of-the-art and evolution analysis carried out for choosing an ontology language in the IST Esperonto project. At first, we analyze changes and evolution that took place in the filed of Semantic Web languages during the last years, in particular, around the ontology languages of the RDF/S and OWL family. Second, we present current trends in development of Semantic Web languages, in particular, rule support extensions for Semantic Web languages and emerging ontology languages such as WSMO languages.
Abstract: In this paper, an extended method of the directionally constrained minimization of power (DCMP) algorithm for broadband signals is proposed. The DCMP algorithm is one of the useful techniques of extracting a target signal from observed signals of a microphone array system. In the DCMP algorithm, output power of the microphone array is minimized under a constraint of constant responses to directions of arrival (DOAs) of specific signals. In our algorithm, by limiting the directional constraint to the perpendicular direction to the sensor array system, the calculating time is reduced.
Abstract: Sensors have been used in various kinds of academic
fields and applications. In this article, we propose the idea of
modularized sensors that combine multiple sensor modules into a
unique sensor. We divide a sensor into several units according to
functionalities. Each unit has different sensor modules, which share
the same type of connectors and can be serially and arbitrarily
connected each other. A user can combine different sensor modules
into a sensor platform according to requirements. Compared with
current modularized sensors, the proposed sensor platform is highly
flexible and reusable. We have implemented the prototype of the
proposed sensor platform, and the experimental results show the
proposed platform can work correctly.
Abstract: In this paper, a new dependable algorithm based on an adaptation of the standard variational iteration method (VIM) is used for analyzing the transition from steady convection to chaos for lowto-intermediate Rayleigh numbers convection in porous media. The solution trajectories show the transition from steady convection to chaos that occurs at a slightly subcritical value of Rayleigh number, the critical value being associated with the loss of linear stability of the steady convection solution. The VIM is treated as an algorithm in a sequence of intervals for finding accurate approximate solutions to the considered model and other dynamical systems. We shall call this technique as the piecewise VIM. Numerical comparisons between the piecewise VIM and the classical fourth-order Runge–Kutta (RK4) numerical solutions reveal that the proposed technique is a promising tool for the nonlinear chaotic and nonchaotic systems.
Abstract: Cassava is one of the top five crops in Cameroon. Its
evolution has remained constant since the independence period and
the production has more than tripled. It is a crop with multiple
industrial capacities but the sector-s business opportunities are
underexploited. Using Strengths, Weaknesses, Opportunities and
Threats analysis method, this paper examines the cassava actual state.
It appraises the sector-s strengths (S), considers suitable measures to
strengthen weaknesses (W), evaluates strategies to fully benefit from
the sector numerous business opportunities (O) and explore means to
convert threats (T) into opportunities. Data were collected from the
ministry of agriculture and rural development and different actors.
The results show that cassava sector embodies many business
opportunities and stands as a raw material provider for many
industries but ultimately requires challenges to be tackled
appropriately.
Abstract: Dual bell nozzle is a promising one among the altitude
adaptation nozzle concepts, which offer increased nozzle
performance in rocket engines. Its advantage is the simplicity it offers
due to the absence of any additional mechanical device or movable
parts. Hence it offers reliability along with improved nozzle
performance as demanded by future launch vehicles. Among other
issues, the flow transition to the extension nozzle of a dual bell
nozzle is one of the major issues being studied in the development of
dual bell nozzle. A parameter named over-expansion factor, which
controls the value of the wall inflection angle, has been reported to
have substantial influence in this transition process. This paper
studies, through CFD and cold flow experiments, the effect of overexpansion
factor on flow transition in dual bell nozzles.
Abstract: In this paper, we propose an improved fast search
algorithm using combined histogram features and temporal division
method for short MPEG video clips from large video database. There
are two types of histogram features used to generate more robust
features. The first one is based on the adjacent pixel intensity
difference quantization (APIDQ) algorithm, which had been reliably
applied to human face recognition previously. An APIDQ histogram is
utilized as the feature vector of the frame image. Another one is
ordinal feature which is robust to color distortion. Combined with
active search [4], a temporal pruning algorithm, fast and robust video
search can be realized. The proposed search algorithm has been
evaluated by 6 hours of video to search for given 200 MPEG video
clips which each length is 30 seconds. Experimental results show the
proposed algorithm can detect the similar video clip in merely 120ms,
and Equal Error Rate (ERR) of 1% is achieved, which is more
accurately and robust than conventional fast video search algorithm.
Abstract: In determining the electromagnetic properties of
magnetic materials, hysteresis modeling is of high importance. Many
models are available to investigate those characteristics but they tend
to be complex and difficult to implement. In this paper a new
qualitative hysteresis model for ferromagnetic core is presented,
based on the function approximation capabilities of adaptive neuro
fuzzy inference system (ANFIS). The proposed ANFIS model
combined the neural network adaptive capabilities and the fuzzy
logic qualitative approach can restored the hysteresis curve with a
little RMS error. The model accuracy is good and can be easily
adapted to the requirements of the application by extending or
reducing the network training set and thus the required amount of
measurement data.
Abstract: From the beginning of creation, human being has ever
fought against the ecosystem by changes has made in environment.
The most environmental changes on the nature have been done after
starting the concentrated life in the same region. Dams are one of the
most important buildings in water resources and transferring. These
buildings have been made from old times without access to
hydrological, hydraulically, hydro mechanical information. Dams
have positive and negative effects on environment. Constructing a
dam relatively causes equal ecological consequences. According to
different criteria, environmental effects of dams can lead short term
and long term damages. These effects may influence on the situation
and treatment of meteorology, biology, culture, ancient works, etc
and severely causes to change and complicate it. So considering
importance of positive effects of dam construction, it is necessary to
minimize negative environmental effects of dams to achieve a stable
development. In this article the considered effects and their solutions
in influencing on assessment of destructive environmental effects of
dams construction have been surveyed and presented.
Abstract: the purpose of this research is to identify and clarify
factors which have positive effect among user satisfaction and their
social networking through websites. The examined factors in this
research are; innovation, ease of use, trustworthy and customer
support which are defined as satisfaction factors. To obtain reliable
research approaches and to have better result in this research four
hypothesizes used to test. This hypothesis testing has been done by
correlation, regression and test of normality by using “SPSS16" also
the data which was analyzed by this software. this data was gathered
from prepaid questionnaire.