Abstract: This study numerically investigates the effects of Electrohydrodynamic on flow patterns and heat transfer enhancement within a cavity which is on the lower wall of channel. In this simulation, effects of using ground wire and ground plate on the flow patterns are compared. Moreover, the positions of electrode wire respecting with ground are tested in the range of angles θ = 0 - 180o. High electrical voltage exposes to air is 20 kV. Bulk mean velocity and temperature of inlet air are controlled at 0.1 m/s and 60 OC, respectively. The result shows when electric field is applied, swirling flow is appeared in the channel. In addition, swirling flow patterns in the main flow of using ground plate are widely spreader than that of using ground wire. Moreover, direction of swirling flow also affects the flow pattern and heat transfer in a cavity. These cause the using ground wire to give the maximum temperature and heat transfer higher than using ground plate. Furthermore, when the angle is at θ = 60o, high shear flow effect is obtained. This results show high strength of swirling flow and effective heat transfer enhancement.
Abstract: Routing security is a major concerned in Wireless
Sensor Network since a large scale of unattended nodes is deployed
in ad hoc fashion with no possibility of a global addressing due to a
limitation of node-s memory and the node have to be self organizing
when the systems require a connection with the other nodes. It
becomes more challenging when the nodes have to act as the router
and tightly constrained on energy and computational capabilities
where any existing security mechanisms are not allowed to be fitted
directly. These reasons thus increasing vulnerabilities to the network
layer particularly and to the whole network, generally. In this paper,
a Dynamic Window Secured Implicit Geographic Forwarding
(DWSIGF) routing is presented where a dynamic time is used for
collection window to collect Clear to Send (CTS) control packet in
order to find an appropriate hoping node. The DWIGF is expected to
minimize a chance to select an attacker as the hoping node that
caused by a blackhole attack that happen because of the CTS rushing
attack, which promise a good network performance with high packet
delivery ratios.
Abstract: In this paper, a numerical study has been made to
analyze the transient 2-D flows of a viscous incompressible fluid
through channels with forward or backward constriction. Problems
addressed include flow through sudden contraction and sudden
expansion channel geometries with rounded and increasingly sharp
reentrant corner. In both the cases, numerical results are presented for
the separation and reattachment points, streamlines, vorticity and
flow patterns. A fourth order accurate compact scheme has been
employed to efficiently capture steady state solutions of the
governing equations. It appears from our study that sharpness of the
throat in the channel is one of the important parameters to control the
strength and size of the separation zone without modifying the
general flow patterns. The comparison between the two cases shows
that the upstream geometry plays a significant role on vortex growth
dynamics.
Abstract: The unsteady wake of an EPPLER 361 airfoil in
pitching motion has been investigated in a subsonic wind tunnel by
hot-wire anemometry. The airfoil was given the pitching motion
about the one-quarter chord axis at reduced frequency of 0182.
Streamwise mean velocity profiles (wake profiles) were investigated
at several vertically aligned points behind the airfoil at one-quarter
chord downstream distance from trailing edge. Oscillation amplitude
and mean angle of attack were varied to determine the effects on
wake profiles. When the maximum dynamic angle of attack was
below the static stall angle of attack, weak effects on wake were
found by increasing oscillation amplitude and mean angle of attack.
But, for higher angles of attack strong unsteady effects were
appeared on the wake.
Abstract: Wrist pulse analysis for identification of health status
is found in Ancient Indian as well as Chinese literature. The preprocessing
of wrist pulse is necessary to remove outlier pulses and
fluctuations prior to the analysis of pulse pressure signal. This paper
discusses the identification of irregular pulses present in the pulse
series and intricacies associated with the extraction of time domain
pulse features. An approach of Dynamic Time Warping (DTW) has
been utilized for the identification of outlier pulses in the wrist pulse
series. The ambiguity present in the identification of pulse features is
resolved with the help of first derivative of Ensemble Average of
wrist pulse series. An algorithm for detecting tidal and dicrotic notch
in individual wrist pulse segment is proposed.
Abstract: In this paper, we analyze the problem of quasiballistic electron transport in ultra small of mercury -cadmiumtelluride (Hg0.8Cd0.2Te -MCT) n+-n- n+ devices from hydrodynamic point view. From our study, we note that, when the size of the active layer is low than 0.1μm and for low bias application( ( ≥ 9mV), the quasi-ballistic transport has an important effect.
Abstract: This paper presents the adaptive control scheme
with sliding mode compensator for vibration control problem
in the presence of disturbance. The dynamic model of the
flexible cantilever beam using finite element modeling is
derived. The adaptive control with sliding mode compensator
using output feedback for output tracking is developed to
reject the external disturbance, and to improve the tracking
performance. Satisfactory simulation results verify that the
effectiveness of adaptive control scheme with sliding mode
compensator.
Abstract: This study aims to assess the vulnerability and risk of
the coastal areas of Taijiang to abnormal oceanographic phenomena.
In addition, this study aims to investigate and collect data regarding
the disaster losses, land utilization, and other social, economic, and
environmental issues in these coastal areas to construct a coastal
vulnerability and risk map based on the obtained climate-change risk
assessment results. Considering the indexes of the three coastal
vulnerability dimensions, namely, man-made facilities, environmental
geography, and social economy, this study adopted the equal
weighting process and Analytic Hierarchy Process to analyze the
vulnerability of these coastal areas to disasters caused by climatic
changes. Among the areas with high coastal vulnerability to climatic
changes, three towns had the highest coastal vulnerability and four had
the highest relative vulnerability. Areas with lower disaster risks were
found to be increasingly vulnerable to disasters caused by climatic
changes as time progresses.
Abstract: In this paper, many techniques for blind identification of moving average (MA) process are presented. These methods utilize third- and fourth-order cumulants of the noisy observations of the system output. The system is driven by an independent and identically distributed (i.i.d) non-Gaussian sequence that is not observed. Two nonlinear optimization algorithms, namely the Gradient Descent and the Gauss-Newton algorithms are exposed. An algorithm based on the joint-diagonalization of the fourth-order cumulant matrices (FOSI) is also considered, as well as an improved version of the classical C(q, 0, k) algorithm based on the choice of the Best 1-D Slice of fourth-order cumulants. To illustrate the effectiveness of our methods, various simulation examples are presented.
Abstract: Using bottom-up image processing algorithms to predict human eye fixations and extract the relevant embedded information in images has been widely applied in the design of active machine vision systems. Scene text is an important feature to be extracted, especially in vision-based mobile robot navigation as many potential landmarks such as nameplates and information signs contain text. This paper proposes an edge-based text region extraction algorithm, which is robust with respect to font sizes, styles, color/intensity, orientations, and effects of illumination, reflections, shadows, perspective distortion, and the complexity of image backgrounds. Performance of the proposed algorithm is compared against a number of widely used text localization algorithms and the results show that this method can quickly and effectively localize and extract text regions from real scenes and can be used in mobile robot navigation under an indoor environment to detect text based landmarks.
Abstract: This paper reviews the optimization available
transmission capability (ATC) of power systems using a device of
FACTS named SSSC equipped with energy storage devices. So that,
emplacement and improvement of parameters of SSSC will be
illustrated. Thus, voltage magnitude constraints of network buses,
line transient stability constraints and voltage breakdown constraints
are considered. To help the calculations, a comprehensive program in
DELPHI is provided, which is able to simulate and trace the
parameters of SSSC has been installed on a specific line.
Furthermore, the provided program is able to compute ATC, TTC
and maximum value of their enhancement after using SSSC.
Abstract: Construction site safety in China has aroused
comprehensive concern all over the world. It is imperative to
investigate the main causes of poor construction site safety. This paper
divides all the causes into four aspects, namely the factors of workers,
object, environment and management and sets up the accident causes
element system based on Delphi Method. This is followed by the
application of structural equation modeling to examine the importance
of each aspect of causes from the standpoints of different roles related
to the construction respectively. The results indicate that all the four
aspects of factors are in need of improvement, and different roles have
different ideas considering the priority of those factors. The paper has
instructive significance for the practitioners to take measures to
improve construction site safety in China accordingly.
Abstract: This paper presents data annotation models at five levels of granularity (database, relation, column, tuple, and cell) of relational data to address the problem of unsuitability of most relational databases to express annotations. These models do not require any structural and schematic changes to the underlying database. These models are also flexible, extensible, customizable, database-neutral, and platform-independent. This paper also presents an SQL-like query language, named Annotation Query Language (AnQL), to query annotation documents. AnQL is simple to understand and exploits the already-existent wide knowledge and skill set of SQL.
Abstract: Aluminum alloy has an extensive range of industrial application due to its consistent mechanical properties and structural integrity. The heat treatment by precipitation technique affected the Magnesium, Silicon Manganese and copper crystals dissolved in the Aluminum alloy. The crystals dislocated to precipitate on the crystal’s boundaries of the Aluminum alloy when given a thermal energy increased its hardness. In this project various times and temperature were varied to find out the best combination of these variables to increase the precipitation of the metals on the Aluminum crystal’s boundaries which will lead to get the highest hardness. These specimens are then tested for their hardness and tensile strength. It is noticed that when the temperature increases, the precipitation increases and consequently the hardness increases. A threshold temperature value (264C0) of Aluminum alloy should not be reached due to the occurrence of recrystalization which causes the crystal to grow. This recrystalization process affected the ductility of the alloy and decrease hardness. In addition, and while increasing the temperature the alloy’s mechanical properties will decrease. The mechanical properties, namely tensile and hardness properties are investigated according to standard procedures. In this research, different temperature and time have been applied to increase hardening.The highest hardness at 100°c in 6 hours equals to 207.31 HBR, while at the same temperature and time the lowest elongation equals to 146.5.
Abstract: Business and IT alignment has continued as a
top concern for business and IT executives for almost three
decades. Many researchers have conducted empirical studies on
the relationship between business-IT alignment and performance.
Yet, these approaches, lacking a social perspective, have had little
impact on sustaining performance and competitive advantage. In
addition to the limited alignment literature that explores
organisational learning that is represented in shared understanding,
communication, cognitive maps and experiences.
Hence, this paper proposes an integrated process that enables
social and intellectual dimensions through the concept of
organisational learning. In particular, the feedback and feedforward
process which provide a value creation across dynamic
multilevel of learning. This mechanism enables on-going
effectiveness through development of individuals, groups and
organisations, which improves the quality of business and IT
strategies and drives to performance.
Abstract: This paper presents a dynamic model for mechanical
loads of an electric drive, including angular misalignment and
including load unbalance. The misalignment model represents the
effects of the universal joint between the motor and the mechanical
load. Simulation results are presented for an induction motor driving
a mechanical load with angular misalignment for both flexible and
rigid coupling. The models presented are very useful in the study of
mechanical fault detection in induction motors, using mechanical and
electrical signals already available in a drive system, such as speed,
torque and stator currents.
Abstract: The three-dimensional incompressible flow past a
rectangular open cavity is investigated, where the aspect ratio of the
cavity is considered as 4. The principle objective is to use large-eddy
simulation to resolve and control the large-scale structures, which are
largely responsible for flow oscillations in a cavity. The flow past an
open cavity is very common in aerospace applications and can be a
cause of acoustic source due to hydrodynamic instability of the shear
layer and its interactions with the downstream edge. The unsteady
Navier-stokes equations have been solved on a staggered mesh using
a symmetry-preserving central difference scheme. Synthetic jet has
been used as an active control to suppress the cavity oscillations in
wake mode for a Reynolds number of ReD = 3360. The effect of
synthetic jet has been studied by varying the jet amplitude and
frequency, which is placed at the upstream wall of the cavity. The
study indicates that there exits a frequency band, which is larger than
a critical value, is effective in attenuating cavity oscillations when
blowing ratio is more than 1.0.
Abstract: This paper proposes an implementation for the
directed diffusion paradigm aids in studying this paradigm-s
operations and evaluates its behavior according to this
implementation. The directed diffusion is evaluated with respect to
the loss percentage, lifetime, end-to-end delay, and throughput.
From these evaluations some suggestions and modifications are
proposed to improve the directed diffusion behavior according to
this implementation with respect to these metrics. The proposed
modifications reflect the effect of local path repair by introducing a
technique called Loop-free Local Path Repair (LLPR) which
improves the directed diffusion behavior especially with respect to
packet loss percentage by about 92.69%. Also LLPR improves the
throughput and end-to-end delay by about 55.31% and 14.06%
respectively, while the lifetime decreases by about 29.79%.
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: The main objectif of this paper is to present a tool that
we have developed subject to characterize and modelling indoor radio
channel propagation at millimetric wave. The tool is based on the
ray tracing technique (RTT). As, in realistic environment we cannot
neglect the significant impact of Human Body Shadowing and other
objects in motion on indoor 60 GHz propagation channel. Hence,
our proposed model allows a simulation of propagation in a dynamic
indoor environment. First, we describe a model of human body.
Second, RTT with this model is used to simulate the propagation
of millimeter waves in the presence of persons in motion. Results
of the simulation show that this tool gives results in agreement with
those reported in the literature. Specially, the effects of people motion
on temporal channel properties.