Abstract: The low power wireless sensor devices which usually
uses the low power wireless private area network (IEEE 802.15.4)
standard are being widely deployed for various purposes and in
different scenarios. IPv6 low power wireless private area network
(6LoWPAN) was adopted as part of the IETF standard for the
wireless sensor devices so that it will become an open standard
compares to other dominated proprietary standards available in the
market. 6LoWPAN also allows the integration and communication of
sensor nodes with the Internet more viable. This paper presents a
comparative study on different available IPv6 platforms for wireless
sensor networks including open and close sources. It also discusses
about the platforms used by these stacks. Finally it evaluates and
provides appropriate suggestions which can be use for selection of
required IPv6 stack for low power devices.
Abstract: Discrete Cosine Transform (DCT) based transform coding is very popular in image, video and speech compression due to its good energy compaction and decorrelating properties. However, at low bit rates, the reconstructed images generally suffer from visually annoying blocking artifacts as a result of coarse quantization. Lapped transform was proposed as an alternative to the DCT with reduced blocking artifacts and increased coding gain. Lapped transforms are popular for their good performance, robustness against oversmoothing and availability of fast implementation algorithms. However, there is no proper study reported in the literature regarding the statistical distributions of block Lapped Orthogonal Transform (LOT) and Lapped Biorthogonal Transform (LBT) coefficients. This study performs two goodness-of-fit tests, the Kolmogorov-Smirnov (KS) test and the 2- test, to determine the distribution that best fits the LOT and LBT coefficients. The experimental results show that the distribution of a majority of the significant AC coefficients can be modeled by the Generalized Gaussian distribution. The knowledge of the statistical distribution of transform coefficients greatly helps in the design of optimal quantizers that may lead to minimum distortion and hence achieve optimal coding efficiency.
Abstract: In this paper, application of Sliding Mode Control (SMC) technique for an Active Magnetic Bearing (AMB) system with varying rotor speed is considered. The gyroscopic effect and mass imbalance inherited in the system is proportional to rotor speed in which this nonlinearity effect causes high system instability as the rotor speed increases. Transformation of the AMB dynamic model into regular system shows that these gyroscopic effect and imbalance lie in the mismatched part of the system. A H2-based sliding surface is designed which bound the mismatched parts. The solution of the surface parameter is obtained using Linear Matrix Inequality (LMI). The performance of the controller applied to the AMB model is demonstrated through simulation works under various system conditions.
Abstract: The study aimed to identify the logical structure of
data and particularities of developing and testing a website designed
for selling farm products through online auctions.
The research is based on a short literature review in the field and
exploratory trials of some successful models from other industries, in
order to identify the advantages of using such tool, as well as the
optimal structure and functionality of an auction portal. In the last
part, the study focuses on the results of testing the website by the
potential beneficiaries.
Conclusions of the study underlines that the particularities of some
agricultural products could raise difficulties in the process of selling
them through online auctions, but the use of such system it is
perceived to bring significant improvements in the supply chain.
The results of scientific investigations require a more detailed
study regarding the importance of using quality standards for
agricultural products sold via online auction, the impact that
implementation of an online payment system could have on trade
with agricultural products and problems which could arise in using
the website in different countries.
Abstract: Speeding represents one of the main concerns for road safety and it still is a subject for research. The need to address this problem and to understand why drivers over speed increases especially in Romania, where in 2011, speed was the main cause of car accidents. This article addresses this problem by using the theory of planned behaviour. A questionnaire was administered to a sample of young Romanian drivers (18 to 25 years) and several path analyses were made in order to verify if the model proposed by the theory of planned behaviour fits the data. One interesting result is that perceived behavioural control does not predict the intention to speed or self-reported driving speed, but subjective norms do. This implies that peers and social environment have a greater impact on young Romanian drivers than we thought.
Abstract: In this paper, a novel multipurpose audio watermarking
algorithm is proposed based on Vector Quantization (VQ) in Discrete
Cosine Transform (DCT) domain using the codeword labeling and
index-bit constrained method. By using this algorithm, it can fulfill the
requirements of both the copyright protection and content integrity
authentication at the same time for the multimedia artworks. The
robust watermark is embedded in the middle frequency coefficients of
the DCT transform during the labeled codeword vector quantization
procedure. The fragile watermark is embedded into the indices of the
high frequency coefficients of the DCT transform by using the
constrained index vector quantization method for the purpose of
integrity authentication of the original audio signals. Both the robust
and the fragile watermarks can be extracted without the original audio
signals, and the simulation results show that our algorithm is effective
with regard to the transparency, robustness and the authentication
requirements
Abstract: In the framework of the image compression by
Wavelet Transforms, we propose a perceptual method by
incorporating Human Visual System (HVS) characteristics in the
quantization stage. Indeed, human eyes haven-t an equal sensitivity
across the frequency bandwidth. Therefore, the clarity of the
reconstructed images can be improved by weighting the quantization
according to the Contrast Sensitivity Function (CSF). The visual
artifact at low bit rate is minimized. To evaluate our method, we use
the Peak Signal to Noise Ratio (PSNR) and a new evaluating criteria
witch takes into account visual criteria. The experimental results
illustrate that our technique shows improvement on image quality at
the same compression ratio.
Abstract: Method of multiple scales is used in the paper in order
to derive an amplitude evolution equation for the most unstable mode
from two-dimensional shallow water equations under the rigid-lid
assumption. It is assumed that shallow mixing layer is slightly curved
in the longitudinal direction and contains small particles. Dynamic
interaction between carrier fluid and particles is neglected. It is
shown that the evolution equation is the complex Ginzburg-Landau
equation. Explicit formulas for the computation of the coefficients of
the equation are obtained.
Abstract: In This paper, the behavior of eccentric braced frame
(EBF) is studied with replacing friction damper (FD) in confluence of these braces, in 5 and 10-storey steel frames. For FD system, the main step is to determine the slip load. For this reason, the performance indexes include roof displacement, base shear, dissipated energy and relative performance should be investigated. In
nonlinear dynamic analysis, the response of structure to three
earthquake records has been obtained and the values of roof
displacement, base shear and column axial force for FD and EBF
frames have been compared. The results demonstrate that use of the FD in frames, in comparison with the EBF, substantially reduces the roof displacement, column axial force and base shear. The obtained results show suitable performance of FD in higher storey structure in
comparison with the EBF.
Abstract: Information and Communications Technologies (ICT) has been integrated in education in many developing and developed countries alike, but the use of ICT in Tanzanian schools is dismal. Many Tanzanian secondary schools have no computers. The few schools with computers use them primarily for secretarial services and computer literacy training. The Tanzanian education system at other levels like secondary school level has to undergo substantial transformation, underscored by the growing application of new information and communication technology. This paper presents the e-readiness survey result from secondary schools in Tanzania. The paper also suggests how Tanzania can make use of the few present ICT resources to support and improve teaching and learning functions to improve performance and acquisition of knowledge by using e-Learning Management System (e-LMS).
Abstract: This main purpose of the study reported here was to
investigate the extent to which the form of school
governance (particularly decision-making) had an impact upon the
effectiveness of the school with reference to parental involvement,
planning and budgeting, professional development of teachers,
school facilities and resources, and student outcomes. Particular
attention was given to decision-making within the governance
arrangements. The study was based on four case studies of high
schools in New South Wales, Australia including one government
school, one independent Christian community school, one
independent Catholic school, and one Catholic systemic school.
The focus of the research was principals, teachers, parents, and
students of four schools with varying governance structures. To
gain a greater insight into the issues, the researchers collected
information by questionnaire, semi-structured interview, and
review of school key documents. This study found that it was not
so much structure but the centrality of the school Principal and the
way that the Principal perceived his/her roles in relation to others
that impacted most on school governance.
Abstract: In recent decade's tourism industry is one of main
reasons of the social and economical development for many
countries; so these countries try to gain more portion of it for
themselves. The excessive natural and cultural touristy potentialities
in Iran made this country to be one of the most attractive sightseeing
areas, although; Iran has got the lowest rate of tourists. Khark Island
is about 32 km. It is a beautiful coral reef coast; about 98% of oil
export has been done through this place. The ecotourism
potentialities of Khark and Kharko Islands (about 3.7km far from
Khark) are the reason to consider ecotourism and the main activity in
these islands which is exporting oil at the same time. This article
refers to way of measuring the geographical coordination of the
place, and the potentialities, ecotourism attraction of the islands and
introduces some ideas in order to expand tourism in the islands.
Abstract: Higher capacities of power plants together with
increased awareness on environmental considerations have led to
taller height of stacks. It is seen that strong wind can result in falling
of stacks. So, aerodynamic consideration of stacks is very important
in order to save the falling of stacks. One stack is not enough in
industries and power sectors and two or three stacks are required for
proper operation of the unit. It is very important to arrange the stacks
in proper way to resist their downfall. The present experimental
study concentrates on the mutual effect of three nearby stacks on
each other at three different arrangements, viz. linear, side-by-side
and triangular. The experiments find out the directions of resultant
forces acting on the stacks in different configurations so that proper
arrangement of supports can be made with respect to the wind
directionality obtained from local meteorological data. One can also
easily ascertain which stack is more vulnerable to wind in
comparison to the others for a particular configuration. Thus, this
study is important in studying the effect of wind force on three stacks
in different arrangements and is very helpful in placing the supports
in proper places in order to avoid failing of stack-like structures due
to wind.
Abstract: In our modern society electricity is vital to our health,
safety, comfort and well-being. While our daily use of electricity is
often taken for granted, public concern has arisen about potential
adverse health effects from electric and magnetic – electromagnetic –
fields (EMFs) produced by our use of electricity.
This paper aims to compare between the measured magnetic field
values and the simulated models for the indoor medium to low
voltage (MV/LV) distribution substations.
To calculate the magnetic flux density in the substations,
interactive software SUBCALC is used which is based on closed
form solution of the Biot-Savart law with 3D conductor model.
The comparison between the measured values and the simulated
models was acceptable. However there were some discrepancies, as
expected, may be due to the current variation during measurements.
Abstract: This paper presents a new study on the applications of
optimization and regression analysis techniques for optimal
calculation of partial ratios of four-step helical gearboxes for getting
minimal gearbox length. In the paper, basing on the moment
equilibrium condition of a mechanic system including four gear units
and their regular resistance condition, models for determination of the
partial ratios of the gearboxes are proposed. In particular, explicit
models for calculation of the partial ratios are proposed by using
regression analysis. Using these models, the determination of the
partial ratios is accurate and simple.
Abstract: In this article we address the problem of mobile robot formation control. Indeed, the most work, in this domain, have studied extensively classical control for keeping a formation of mobile robots. In this work, we design an FLC (Fuzzy logic Controller) controller for separation and bearing control (SBC). Indeed, the leader mobile robot is controlled to follow an arbitrary reference path, and the follower mobile robot use the FSBC (Fuzzy Separation and Bearing Control) to keep constant relative distance and constant angle to the leader robot. The efficiency and simplicity of this control law has been proven by simulation on different situation.
Abstract: The study entitled “The Construction of Interactive
Computer Multimedia Instruction on Basic Japanese Vocabulary"
was aimed: 1) To construct the interactive computer multimedia
instruction on Basic Japanese Vocabulary, 2) To find out
multimedia-s quality, 3) To examine the student-s satisfaction and 4)
To study the learning achievement in Basic Japanese vocabulary. The
sampling group used in this study was composed of 40 1st year
student in Educational Communications and Technology Department,
Faculty of Industrial Education and Technology, King Mongkut-s
University of Technology Thonburi, in the academic year 2553 B.E.
(2010). According to research results, we found that 1). The quality
assessment by 3 mass media experts was at 4.72 on average or at high
level. 2) In terms of contents, the evaluation by 3 experts was at 4.81
on average or at high level. 3) In terms of achievement, there was a
statistical significance between before and after the treatment at the
.05 level. 4) The satisfaction of students towards the interactive
computer multimedia Instruction on “Basic Japanese Vocabulary"
was 4.35 on average, or at high level.
Abstract: In contrast to existing methods which do not take into account multiconnectivity in a broad sense of this term, we develop mathematical models and highly effective combination (BIEM and FDM) numerical methods of calculation of stationary and quasistationary temperature field of a profile part of a blade with convective cooling (from the point of view of realization on PC). The theoretical substantiation of these methods is proved by appropriate theorems. For it, converging quadrature processes have been developed and the estimations of errors in the terms of A.Ziqmound continuity modules have been received. For visualization of profiles are used: the method of the least squares with automatic conjecture, device spline, smooth replenishment and neural nets. Boundary conditions of heat exchange are determined from the solution of the corresponding integral equations and empirical relationships. The reliability of designed methods is proved by calculation and experimental investigations heat and hydraulic characteristics of the gas turbine first stage nozzle blade.
Abstract: This paper presents a smart-card applet that is able to
verify X.509 certificates and to use the public key contained in the
certificate for verifying digital signatures that have been created
using the corresponding private key, e.g. for the purpose of authenticating
the certificate owner against the card. The approach has been
implemented as an operating prototype on Java cards.
Abstract: The issue of classifying objects into one of predefined
groups when the measured variables are mixed with different types
of variables has been part of interest among statisticians in many
years. Some methods for dealing with such situation have been
introduced that include parametric, semi-parametric and nonparametric
approaches. This paper attempts to discuss on a problem
in classifying a data when the number of measured mixed variables is
larger than the size of the sample. A propose idea that integrates a
dimensionality reduction technique via principal component analysis
and a discriminant function based on the location model is discussed.
The study aims in offering practitioners another potential tool in a
classification problem that is possible to be considered when the
observed variables are mixed and too large.