Abstract: Mobile Ad Hoc network is an infrastructure less
network which operates with the coordination of each node. Each node
believes to help another node, by forwarding its data to/from another
node. Unlike a wired network, nodes in an ad hoc network are resource
(i.e. battery, bandwidth computational capability and so on)
constrained. Such dependability of one node to another and limited
resources of nodes can result in non cooperation by any node to
accumulate its resources. Such non cooperation is known as selfish
behavior.
This paper discusses the performance analysis of very well known
MANET single-path (i.e. AODV) and multi-path (i.e. AOMDV)
routing protocol, in the presence of selfish behaviors. Along with
existing selfish behaviors, a new variation is also studied. Extensive
simulations were carried out using ns-2 and the study concluded that
the multi-path protocol (i.e. AOMDV) with link disjoint configuration
outperforms the other two configurations.
Abstract: All the geophysical phenomena including river
networks and flow time series are fractal events inherently and fractal
patterns can be investigated through their behaviors. A non-linear
system like a river basin can well be analyzed by a non-linear
measure such as the fractal analysis. A bilateral study is held on the
fractal properties of the river network and the river flow time series.
A moving window technique is utilized to scan the fractal properties
of them. Results depict both events follow the same strategy
regarding to the fractal properties. Both the river network and the
time series fractal dimension tend to saturate in a distinct value.
Abstract: Several wireless networks security standards have been proposed and widely implemented in both business and home environments in order to protect the network from unauthorized access. However, the implementation of such standards is usually achieved by network administrators without even knowing the standards- weaknesses and strengths. The intention of this paper is to evaluate and analyze the impact over the network-s security due to the implementation of the wireless networks security standards WEP, WPA and WLAN 802.1X.
Abstract: If an unsteady heat transfer or heat impulse happens in
part of the cryogenic pipeline system of large space environment
simulation equipment while running in vacuum environment, it will
lead to abnormal flow of the cryogenic fluid in the pipeline. When the
situation gets worse, the cryogenic fluid in the pipeline will have phase
change and a gas block which results in the malfunction of the
cryogenic pipeline system. Referring to the structural parameter of a
typical cryogenic pipeline system and the basic equation, an analytical
model and a calculation model for cryogenic pipeline system can be
built. The various factors which influence the thermal resistance of a
cryogenic pipeline system can be analyzed and calculated by using the
qualitative analysis relation deduced for thermal resistance of pipeline.
The research conclusion could provide theoretical support for the
design and operation of a cryogenic pipeline system
Abstract: Wireless capsule Endoscopy (WCE) has rapidly
shown its wide applications in medical domain last ten years
thanks to its noninvasiveness for patients and support for thorough
inspection through a patient-s entire digestive system including
small intestine. However, one of the main barriers to efficient
clinical inspection procedure is that it requires large amount of
effort for clinicians to inspect huge data collected during the
examination, i.e., over 55,000 frames in video. In this paper, we
propose a method to compute meaningful motion changes of
WCE by analyzing the obtained video frames based on regional
optical flow estimations. The computed motion vectors are used to
remove duplicate video frames caused by WCE-s imaging nature,
such as repetitive forward-backward motions from peristaltic
movements. The motion vectors are derived by calculating
directional component vectors in four local regions. Our
experiments are performed on small intestine area, which is of
main interest to clinical experts when using WCEs, and our
experimental results show significant frame reductions comparing
with a simple frame-to-frame similarity-based image reduction
method.
Abstract: Two different superhydrophobic surfaces were
elaborated and their oil repellency behavior was evaluated using
several liquid with different surface tension. A silicone rubber/SiO2
nanocomposite coated (A) on aluminum substrate by “spin-coating"
and the sample B was an anodized aluminum surface covered by
Teflon-like coating. A high static contact angle about ∼162° was
measured for two prepared surfaces on which the water droplet rolloff.
Scanning electron microscopy (SEM) showed the presence of
micro/nanostructures for both sample A and B similar to that of lotus
leaf.
However the sample A presented significantly different behaviour
of wettability against the low surface tension liquid. Sample A has
been wetted totally by oil (dodecan) droplet while sample B showed
oleophobic behaviour. Oleophobic property of Teflon like coating
can be contributed to the presence of CF2 and CF3 functional group
which was shown by XPS analysis.
Abstract: This research aims at development of the Multiple
Intelligences Measurement of Elementary Students. The structural
accuracy test and normality establishment are based on the Multiple
Intelligences Theory of Gardner. This theory consists of eight aspects
namely linguistics, logic and mathematics, visual-spatial relations,
body and movement, music, human relations, self-realization/selfunderstanding
and nature. The sample used in this research consists
of elementary school students (aged between 5-11 years). The size of
the sample group was determined by Yamane Table. The group has
2,504 students. Multistage Sampling was used. Basic statistical
analysis and construct validity testing were done using confirmatory
factor analysis. The research can be summarized as follows; 1.
Multiple Intelligences Measurement consisting of 120 items is
content-accurate. Internal consistent reliability according to the
method of Kuder-Richardson of the whole Multiple Intelligences
Measurement equals .91. The difficulty of the measurement test is
between .39-.83. Discrimination is between .21-.85. 2). The Multiple
Intelligences Measurement has construct validity in a good range,
that is 8 components and all 120 test items have statistical
significance level at .01. Chi-square value equals 4357.7; p=.00 at the
degree of freedom of 244 and Goodness of Fit Index equals 1.00.
Adjusted Goodness of Fit Index equals .92. Comparative Fit Index
(CFI) equals .68. Root Mean Squared Residual (RMR) equals 0.064
and Root Mean Square Error of Approximation equals 0.82. 3). The
normality of the Multiple Intelligences Measurement is categorized
into 3 levels. Those with high intelligence are those with percentiles
of more than 78. Those with moderate/medium intelligence are those
with percentiles between 24 and 77.9. Those with low intelligence
are those with percentiles from 23.9 downwards.
Abstract: In recent years Malaysia has included renewable
energy as an alternative fuel to help in diversifying the country-s
energy reliance on oil, natural gas, coal and hydropower with
biomass and solar energy gaining priority. The scope of this paper is
to look at the designing procedures and analysis of a solar thermal
parabolic trough concentrator by simulation utilizing meteorological
data in several parts of Malaysia. Parameters which include the
aperture area, the diameter of the receiver and the working fluid may
be varied to optimize the design. Aperture area is determined by
considering the width and the length of the concentrator whereas the
geometric concentration ratio (CR) is obtained by considering the
width and diameter of the receiver. Three types of working fluid are
investigated. Theoretically, concentration ratios can be very high in
the range of 10 to 40 000 depending on the optical elements used and
continuous tracking of the sun. However, a thorough analysis is
essential as discussed in this paper where optical precision and
thermal analysis must be carried out to evaluate the performance of
the parabolic trough concentrator as the theoretical CR is not the only
factor that should be considered.
Abstract: The nickel and gold nanoclusters as supported
catalysts were analyzed by XAS, XRD and XPS in order to
determine their local, global and electronic structure. The present
study has pointed out a strong deformation of the local structure of
the metal, due to its interaction with oxide supports. The average
particle size, the mean squares of the microstrain, the particle size
distribution and microstrain functions of the supported Ni and Au
catalysts were determined by XRD method using Generalized Fermi
Function for the X-ray line profiles approximation. Based on EXAFS
analysis we consider that the local structure of the investigated
systems is strongly distorted concerning the atomic number pairs.
Metal-support interaction is confirmed by the shape changes of the
probability densities of electron transitions: Ni K edge (1s →
continuum and 2p), Au LIII-edge (2p3/2 → continuum, 6s, 6d5/2 and
6d3/2). XPS investigations confirm the metal-support interaction at
their interface.
Abstract: The Influence Diagrams (IDs) is a kind of Probabilistic Belief Networks for graphic modeling. The usage of IDs can improve the communication among field experts, modelers, and decision makers, by showing the issue frame discussed from a high-level point of view. This paper enhances the Time-Sliced Influence Diagrams (TSIDs, or called Dynamic IDs) based formalism from a Discrete Event Systems Modeling and Simulation (DES M&S) perspective, for Exploring Analysis (EA) modeling. The enhancements enable a modeler to specify times occurred of endogenous events dynamically with stochastic sampling as model running and to describe the inter- influences among them with variable nodes in a dynamic situation that the existing TSIDs fails to capture. The new class of model is named Dynamic-Stochastic Influence Diagrams (DSIDs). The paper includes a description of the modeling formalism and the hiberarchy simulators implementing its simulation algorithm, and shows a case study to illustrate its enhancements.
Abstract: In this study, stress distributions on dental implants
made of functionally graded biomaterials (FGBM) are investigated
numerically. The implant body is considered to be subjected to axial
compression loads. Numerical problem is assumed to be 2D, and
ANSYS commercial software is used for the analysis. The cross
section of the implant thread varies as varying the height (H) and the
width (t) of the thread. According to thread dimensions of implant
and material properties of FGBM, equivalent stress distribution on
the implant is determined and presented with contour plots along
with the maximum equivalent stress values. As a result, with
increasing material gradient parameter (n), the equivalent stress
decreases, but the minimum stress distribution increases. Maximum
stress values decrease with decreasing implant radius (r). Maximum
von Mises stresses increases with decreasing H when t is constant.
On the other hand, the stress values are not affected by variation of t
in the case of H = constant.
Abstract: In this article, we aim to discuss the formulation of two explicit group iterative finite difference methods for time-dependent two dimensional Burger-s problem on a variable mesh. For the non-linear problems, the discretization leads to a non-linear system whose Jacobian is a tridiagonal matrix. We discuss the Newton-s explicit group iterative methods for a general Burger-s equation. The proposed explicit group methods are derived from the standard point and rotated point Crank-Nicolson finite difference schemes. Their computational complexity analysis is discussed. Numerical results are given to justify the feasibility of these two proposed iterative methods.
Abstract: Xanthan gum is one of the major commercial
biopolymers. Due to its excellent rheological properties xanthan gum
is used in many applications, mainly in food industry. Commercial
production of xanthan gum uses glucose as the carbon substrate;
consequently the price of xanthan production is high. One of the
ways to decrease xanthan price, is using cheaper substrate like
agricultural wastes. Iran is one of the biggest date producer countries.
However approximately 50% of date production is wasted annually.
The goal of this study is to produce xanthan gum from waste date
using Xanthomonas campestris PTCC1473 by submerged
fermentation. In this study the effect of three variables including
phosphor and nitrogen amount and agitation rate in three levels using
response surface methodology (RSM) has been studied. Results
achieved from statistical analysis Design Expert 7.0.0 software
showed that xanthan increased with increasing level of phosphor.
Low level of nitrogen leaded to higher xanthan production. Xanthan
amount, increasing agitation had positive influence. The statistical
model identified the optimum conditions nitrogen amount=3.15g/l,
phosphor amount=5.03 g/l and agitation=394.8 rpm for xanthan. To
model validation, experiments in optimum conditions for xanthan
gum were carried out. The mean of result for xanthan was 6.72±0.26.
The result was closed to the predicted value by using RSM.
Abstract: Using activity theory, organisational theory and
didactics as theoretical foundations, a comprehensive model of the
organisational dimensions relevant for learning and knowledge
transfer will be developed. In a second step, a Learning Assessment
Guideline will be elaborated. This guideline will be designed to
permit a targeted analysis of organisations to identify the status quo
in those areas crucial to the implementation of learning and
knowledge transfer. In addition, this self-analysis tool will enable
learning managers to select adequate didactic models for e- and
blended learning. As part of the European Integrated Project
"Process-oriented Learning and Information Exchange" (PROLIX),
this model of organisational prerequisites for learning and knowledge
transfer will be empirically tested in four profit and non-profit
organisations in Great Britain, Germany and France (to be finalized
in autumn 2006). The findings concern not only the capability of the
model of organisational dimensions, but also the predominant
perceptions of and obstacles to learning in organisations.
Abstract: Leptospirosis is recognized as an important zoonosis
in tropical regions well as an important animal disease with
substantial loss in production. In this study, the model for the
transmission of the Leptospirosis disease to human population are
discussed. Model is described the vector population dynamics and
the Leptospirosis transmission to the human population are
discussed. Local analysis of equilibria are given. We confirm the
results by using numerical results.
Abstract: Identity verification of authentic persons by their multiview faces is a real valued problem in machine vision. Multiview faces are having difficulties due to non-linear representation in the feature space. This paper illustrates the usability of the generalization of LDA in the form of canonical covariate for face recognition to multiview faces. In the proposed work, the Gabor filter bank is used to extract facial features that characterized by spatial frequency, spatial locality and orientation. Gabor face representation captures substantial amount of variations of the face instances that often occurs due to illumination, pose and facial expression changes. Convolution of Gabor filter bank to face images of rotated profile views produce Gabor faces with high dimensional features vectors. Canonical covariate is then used to Gabor faces to reduce the high dimensional feature spaces into low dimensional subspaces. Finally, support vector machines are trained with canonical sub-spaces that contain reduced set of features and perform recognition task. The proposed system is evaluated with UMIST face database. The experiment results demonstrate the efficiency and robustness of the proposed system with high recognition rates.
Abstract: Based on an analysis of the current research and application of Road maintenance, geographic information system (WebGIS) and ArcGIS Server, the platform overhead construction for Road maintenance development is studied and the key issues are presented, including the organization and design of spatial data on the basis of the geodatabase technology, middleware technology, tiles cache index technology and dynamic segmentation of WebGIS. Road maintenance geographic information platform is put forward through the researching ideas of analysis of the system design. The design and application of WebGIS system are discussed on the basis of a case study of BaNan district of Chongqing highway maintenance management .The feasibility of the theories and methods are validated through the system.
Abstract: The objectives of this research paper were to study the
influencing factors that contributed to the success of electronic
commerce (e-commerce) and to study the approach to enhance the
standard of e-commerce for small and medium enterprises (SME).
The research paper focused the study on only sole proprietorship
SMEs in Bangkok, Thailand. The factors contributed to the success
of SME included business management, learning in the organization,
business collaboration, and the quality of website. A quantitative and
qualitative mixed research methodology was used. In terms of
quantitative method, a questionnaire was used to collect data from
251 sole proprietorships. The System Equation Model (SEM) was
utilized as the tool for data analysis. In terms of qualitative method,
an in-depth interview, a dialogue with experts in the field of ecommerce
for SMEs, and content analysis were used.
By using the adjusted causal relationship structure model, it was
revealed that the factors affecting the success of e-commerce for
SMEs were found to be congruent with the empirical data. The
hypothesis testing indicated that business management influenced the
learning in the organization, the learning in the organization
influenced business collaboration and the quality of the website, and
these factors, in turn, influenced the success of SMEs. Moreover, the
approach to enhance the standard of SMEs revealed that the majority
of respondents wanted to enhance the standard of SMEs to a high
level in the category of safety of e-commerce system, basic structure
of e-commerce, development of staff potentials, assistance of budget
and tax reduction, and law improvement regarding the e-commerce
respectively.
Abstract: Self-efficacy, self-reliance, and motivation were
examined in a quasi-experimental study with 178 sophomore
university students. Participants used an interactive cardiovascular
anatomy and physiology CD-ROM, and completed a 15-item
questionnaire. Reliability of the questionnaire was established using
Cronbach-s alpha. Post-tests and course grades were examined using
a t-test, demonstrating no significance. Results of an item-to-item
analysis of the questionnaire showed overall satisfaction with the
teaching methodology and varied results for self-efficacy, selfreliance,
and motivation. Kendall-s Tau was calculated for all items
in the questionnaire.
Abstract: The aim of this paper is to propose a mathematical
model to determine invariant sets, set covering, orbits and, in
particular, attractors in the set of tourism variables. Analysis was
carried out based on a pre-designed algorithm and applying our
interpretation of chaos theory developed in the context of General
Systems Theory. This article sets out the causal relationships
associated with tourist flows in order to enable the formulation of
appropriate strategies. Our results can be applied to numerous cases.
For example, in the analysis of tourist flows, these findings can be
used to determine whether the behaviour of certain groups affects that
of other groups and to analyse tourist behaviour in terms of the most
relevant variables. Unlike statistical analyses that merely provide
information on current data, our method uses orbit analysis to
forecast, if attractors are found, the behaviour of tourist variables in
the immediate future.