Abstract: One of the functions of the commercial heavy vehicle
is to safely and efficiently transport goods and people. Due to its size
and carrying capacity, it is important to study the vehicle dynamic
stability during cornering. Study has shown that there are a number of
overloaded heavy vehicles or permissible Gross Vehicle Weight
(GVW) violations recorded at selected areas in Malaysia assigned by
its type and category. Thus, the objective of this study is to
investigate the correlation and effect of the GVW on heavy vehicle
stability during cornering event using simulation. Various selected
heavy vehicle types and category are simulated using IPG/Truck
Maker® with different GVW and road condition (coefficient of
friction of road surface), while the speed, driver characteristic, center
of gravity of load and road geometry are constant. Based on the
analysis, the relationship between GVW and lateral acceleration were
established. As expected, on the same value of coefficient of friction,
the maximum lateral acceleration would be increased as the GVW
increases.
Abstract: In this paper, we propose moving object detection
method which is helpful for driver to safely take his/her car out of
parking lot. When moving objects such as motorbikes, pedestrians,
the other cars and some obstacles are detected at the rear-side of host
vehicle, the proposed algorithm can provide to driver warning. We
assume that the host vehicle is just before departure. Gaussian
Mixture Model (GMM) based background subtraction is basically
applied. Pre-processing such as smoothing and post-processing as
morphological filtering are added. We examine “which color space
has better performance for detection of moving objects?” Three color
spaces including RGB, YCbCr, and Y are applied and compared, in
terms of detection rate. Through simulation, we prove that RGB
space is more suitable for moving object detection based on
background subtraction.
Abstract: The main purpose of this study is static analysis of
two three-degree of freedom parallel mechanisms: 3-RCC and 3-
RRS. Geometry of these mechanisms is expressed and static
equilibrium equations are derived for the whole chains. For these
mechanisms due to the equal number of equations and unknowns, the
solution is as same as 3-RCC mechanism. A mathematical software is
used to solve the equations. In order to prove the results obtained
from solving the equations of mechanisms, the CAD model of these
robots has been simulated and their static is analysed in ADAMS
software. Due to symmetrical geometry of the mechanisms, the force
and external torque acting on the end-effecter have been considered
asymmetric to prove the generality of the solution method. Finally,
the results of both softwares, for both mechanisms are extracted and
compared as graphs. The good achieved comparison between the
results indicates the accuracy of the analysis.
Abstract: In recent years, multi-antenna techniques are being considered as a potential solution to increase the flow of future wireless communication systems. The objective of this article is to study the emission and reception system MIMO (Multiple Input Multiple Output), and present the different reception decoding techniques. First we will present the least complex technical, linear receivers such as the zero forcing equalizer (ZF) and minimum mean squared error (MMSE). Then a nonlinear technique called ordered successive cancellation of interferences (OSIC) and the optimal detector based on the maximum likelihood criterion (ML), finally, we simulate the associated decoding algorithms for MIMO system such as ZF, MMSE, OSIC and ML, thus a comparison of performance of these algorithms in MIMO context.
Abstract: Model predictive control is a kind of optimal feedback
control in which control performance over a finite future is optimized
with a performance index that has a moving initial time and a moving
terminal time. This paper examines the stability of model predictive
control for linear discrete-time systems with additive stochastic
disturbances. A sufficient condition for the stability of the closed-loop
system with model predictive control is derived by means of a linear
matrix inequality. The objective of this paper is to show the results
of computational simulations in order to verify the effectiveness of
the obtained stability condition.
Abstract: The sea waves carry thousands of GWs of power
globally. Although there are a number of different approaches to
harness offshore energy, they are likely to be expensive, practically
challenging, and vulnerable to storms. Therefore, this paper considers
using the near shore waves for generating mechanical and electrical
power. It introduces two new approaches, the wave manipulation and
using a variable duct turbine, for intercepting very wide wave fronts
and coping with the fluctuations of the wave height and the sea level,
respectively. The first approach effectively allows capturing much
more energy yet with a much narrower turbine rotor. The second
approach allows using a rotor with a smaller radius but captures
energy of higher wave fronts at higher sea levels yet preventing it
from totally submerging. To illustrate the effectiveness of the first
approach, the paper contains a description and the simulation results
of a scale model of a wave manipulator. Then, it includes the results
of testing a physical model of the manipulator and a single duct, axial
flow turbine in a wave flume in the laboratory. The paper also
includes comparisons of theoretical predictions, simulation results,
and wave flume tests with respect to the incident energy, loss in wave
manipulation, minimal loss, brake torque, and the angular velocity.
Abstract: This paper presents the performance of Integrated
Bacterial Foraging Optimization and Particle Swarm Optimization
(IBFO_PSO) technique in MANET routing. The BFO is a bio-inspired
algorithm, which simulates the foraging behavior of bacteria.
It is effectively applied in improving the routing performance in
MANET. In results, it is proved that the PSO integrated with BFO
reduces routing delay, energy consumption and communication
overhead.
Abstract: Dynamics of a rotor supported by air bearings is
strongly depends on the pressure distribution between the rotor and
the bearing. In this study, internal pressure in air bearings is
numerical and experimental analyzed for different radial clearances.
Firstly the pressure distribution between rotor and bearing is modeled
using Reynold's equation and this model is solved numerically. The
rotor-bearing system is also modeled in four degree of freedom and it
is simulated for different radial clearances. Then, in order to validate
numerical results, a test rig is designed and the rotor bearing system
is run under the same operational conditions. Pressure signals of left
and right bearings are recorded. Internal pressure variations are
compared for numerical and experimental results for different radial
clearances.
Abstract: In this paper, we proposed a novel SCR (Silicon Controlled
Rectifier) - based ESD (Electrostatic Discharge) protection device for I/O
and power clamp. The proposed device has a higher holding voltage
characteristic than conventional SCR. These characteristics enable to have
latch-up immunity under normal operating conditions as well as superior full
chip ESD protection. The proposed device was analyzed to figure out
electrical characteristics and tolerance robustness in term of individual
design parameters (D1, D2, D3). They are investigated by using the
Synopsys TCAD simulator. As a result of simulation, holding voltage
increased with different design parameters. The holding voltage of the
proposed device changes from 3.3V to 7.9V. Also, N-Stack structure ESD
device with the high holding voltage is proposed. In the simulation results,
2-stack has holding voltage of 6.8V and 3-stack has holding voltage of
10.5V. The simulation results show that holding voltage of stacking
structure can be larger than the operation voltage of high-voltage
application.
Abstract: Adopting Most Advantageous Tender (MAT) for the
government procurement projects has become popular in Taiwan. As
time pass by, the problems of MAT has appeared gradually. People
condemn two points that are the result might be manipulated by a
single committee member’s partiality and how to make a fair decision
when the winner has two or more. Arrow’s Impossibility Theorem
proposed that the best scoring method should meet the four reasonable
criteria. According to these four criteria this paper constructed an
“Illegitimate Scores Checking Scheme” for a scoring method and used
the scheme to find out the illegitimate of the current evaluation method
of MAT. This paper also proposed a new scoring method that is called
the “Standardizing Overall Evaluated Score Method”. This method
makes each committee member’s influence tend to be identical. Thus,
the committee members can scoring freely according to their partiality
without losing the fairness. Finally, it was examined by a large-scale
simulation, and the experiment revealed that the it improved the
problem of dictatorship and perfectly avoided the situation of cyclical
majorities, simultaneously. This result verified that the Standardizing
Overall Evaluated Score Method is better than any current evaluation
method of MAT.
Abstract: This paper proposed the comparison made between
Multi-Carrier Pulse Width Modulation, Sinusoidal Pulse Width
Modulation and Selective Harmonic Elimination Pulse Width
Modulation technique for minimization of Total Harmonic Distortion
in Cascaded H-Bridge Multi-Level Inverter. In Multicarrier Pulse
Width Modulation method by using Alternate Position of Disposition
scheme for switching pulse generation to Multi-Level Inverter.
Another carrier based approach; Sinusoidal Pulse Width Modulation
method is also implemented to define the switching pulse generation
system in the multi-level inverter. In Selective Harmonic Elimination
method using Genetic Algorithm and Particle Swarm Optimization
algorithm for define the required switching angles to eliminate low
order harmonics from the inverter output voltage waveform and
reduce the total harmonic distortion value. So, the results validate that
the Selective Harmonic Elimination Pulse Width Modulation method
does capably eliminate a great number of precise harmonics and
minimize the Total Harmonic Distortion value in output voltage
waveform in compared with Multi-Carrier Pulse Width Modulation
method, Sinusoidal Pulse Width Modulation method. In this paper,
comparison of simulation results shows that the Selective Harmonic
Elimination method can attain optimal harmonic minimization
solution better than Multi-Carrier Pulse Width Modulation method,
Sinusoidal Pulse Width Modulation method.
Abstract: The numerical simulation has made tremendous
advances in investigating the blood flow phenomenon through elastic
arteries. Such study can be useful in demonstrating the disease
progression and hemodynamics of cardiovascular diseases such as
atherosclerosis. In the present study, patient specific case diagnosed
with partially stenosed complete right ICA and normal left carotid
bifurcation without any atherosclerotic plaque formation is
considered. 3D patient specific carotid bifurcation model is generated
based on CT scan data using MIMICS-4.0 and numerical analysis is
performed using FSI solver in ANSYS-14.5. The blood flow is
assumed to be incompressible, homogenous and Newtonian, while
the artery wall is assumed to be linearly elastic. The two-way
sequentially coupled transient FSI analysis is performed using FSI
solver for three pulse cycles. The hemodynamic parameters such as
flow pattern, Wall Shear Stress, pressure contours and arterial wall
deformation are studied at the bifurcation and critical zones such as
stenosis. The variation in flow behavior is studied throughout the
pulse cycle. Also, the simulation results reveal that there is a
considerable increase in the flow behavior in stenosed carotid in
contrast to the normal carotid bifurcation system. The investigation
also demonstrates the disturbed flow pattern especially at the
bifurcation and stenosed zone elevating the hemodynamics,
particularly during peak systole and later part of the pulse cycle. The
results obtained agree well with the clinical observation and
demonstrates the potential of patient specific numerical studies in
prognosis of disease progression and plaque rupture.
Abstract: STRIM (Statistical Test Rule Induction Method) has been proposed as a method to effectively induct if-then rules from the decision table which is considered as a sample set obtained from the population of interest. Its usefulness has been confirmed by simulation experiments specifying rules in advance, and by comparison with conventional methods. However, scope for future development remains before STRIM can be applied to the analysis of real-world data sets. The first requirement is to determine the size of the dataset needed for inducting true rules, since finding statistically significant rules is the core of the method. The second is to examine the capacity of rule induction from datasets with contaminated attribute values created by missing data and noise, since real-world datasets usually contain such contaminated data. This paper examines the first problem theoretically, in connection with the rule length. The second problem is then examined in a simulation experiment, utilizing the critical size of dataset derived from the first step. The experimental results show that STRIM is highly robust in the analysis of datasets with contaminated attribute values, and hence is applicable to real-world data
Abstract: In this study, three robust predicting methods, namely artificial neural network (ANN), adaptive neuro fuzzy inference system (ANFIS) and support vector machine (SVM) were used for computing the resonant frequency of A-shaped compact microstrip antennas (ACMAs) operating at UHF band. Firstly, the resonant frequencies of 144 ACMAs with various dimensions and electrical parameters were simulated with the help of IE3D™ based on method of moment (MoM). The ANN, ANFIS and SVM models for computing the resonant frequency were then built by considering the simulation data. 124 simulated ACMAs were utilized for training and the remaining 20 ACMAs were used for testing the ANN, ANFIS and SVM models. The performance of the ANN, ANFIS and SVM models are compared in the training and test process. The average percentage errors (APE) regarding the computed resonant frequencies for training of the ANN, ANFIS and SVM were obtained as 0.457%, 0.399% and 0.600%, respectively. The constructed models were then tested and APE values as 0.601% for ANN, 0.744% for ANFIS and 0.623% for SVM were achieved. The results obtained here show that ANN, ANFIS and SVM methods can be successfully applied to compute the resonant frequency of ACMAs, since they are useful and versatile methods that yield accurate results.
Abstract: The modeling lung respiratory system that has complex anatomy and biophysics presents several challenges including tissue-driven flow patterns and wall motion. Also, the pulmonary lung system because of that they stretch and recoil with each breath, has not static walls and structures. The direct relationship between air flow and tissue motion in the lung structures naturally prefers an FSI simulation technique. Therefore, in order to toward the realistic simulation of pulmonary breathing mechanics the development of a coupled FSI computational model is an important step. A simple but physiologically relevant three-dimensional deep long geometry is designed and fluid-structure interaction (FSI) coupling technique is utilized for simulating the deformation of the lung parenchyma tissue that produces airflow fields. The real understanding of respiratory tissue system as a complex phenomenon have been investigated with respect to respiratory patterns, fluid dynamics and tissue viscoelasticity and tidal breathing period.
Abstract: This paper reviews the model-based qualitative and
quantitative Operations Management research in the context of
Construction Supply Chain Management (CSCM). Construction
industry has been traditionally blamed for low productivity, cost and
time overruns, waste, high fragmentation and adversarial
relationships. The construction industry has been slower than other
industries to employ the Supply Chain Management (SCM) concept
and develop models that support the decision-making and planning.
However the last decade there is a distinct shift from a project-based
to a supply-based approach of construction management. CSCM
comes up as a new promising management tool of construction
operations and improves the performance of construction projects in
terms of cost, time and quality. Modeling the Construction Supply
Chain (CSC) offers the means to reap the benefits of SCM, make
informed decisions and gain competitive advantage. Different
modeling approaches and methodologies have been applied in the
multi-disciplinary and heterogeneous research field of CSCM. The
literature review reveals that a considerable percentage of the CSC
modeling research accommodates conceptual or process models
which present general management frameworks and do not relate to
acknowledged soft Operations Research methods. We particularly
focus on the model-based quantitative research and categorize the
CSCM models depending on their scope, objectives, modeling
approach, solution methods and software used. Although over the last
few years there has been clearly an increase of research papers on
quantitative CSC models, we identify that the relevant literature is
very fragmented with limited applications of simulation,
mathematical programming and simulation-based optimization. Most
applications are project-specific or study only parts of the supply
system. Thus, some complex interdependencies within construction
are neglected and the implementation of the integrated supply chain
management is hindered. We conclude this paper by giving future
research directions and emphasizing the need to develop optimization
models for integrated CSCM. We stress that CSC modeling needs a
multi-dimensional, system-wide and long-term perspective. Finally,
prior applications of SCM to other industries have to be taken into
account in order to model CSCs, but not without translating the
generic concepts to the context of construction industry.
Abstract: Supply chains are the backbone of trade and
commerce. Their logistics use different transport corridors on regular
basis for operational purpose. The international supply chain
transport corridors include different infrastructure elements (e.g.
weighbridge, package handling equipments, border clearance
authorities, and so on). This paper presents the use of multi-agent
systems (MAS) to model and simulate some aspects of transportation
corridors, and in particular the area of weighbridge resource
optimization for operational profit. An underlying multi-agent model
provides a means of modeling the relationships among stakeholders
in order to enable coordination in a transport corridor environment.
Simulations of the costs of container unloading, reloading, and
waiting time for queuing up tracks have been carried out using data
sets. Results of the simulation provide the potential guidance in
making decisions about optimal service resource allocation in a trade
corridor.
Abstract: Boiling process is characterized by the rapid
formation of vapour bubbles at the solid–liquid interface (nucleate
boiling) with pre-existing vapour or gas pockets. Computational fluid
dynamics (CFD) is an important tool to study bubble dynamics. In
the present study, CFD simulation has been carried out to determine
the bubble detachment diameter and its terminal velocity. Volume of
fluid method is used to model the bubble and the surrounding by
solving single set of momentum equations and tracking the volume
fraction of each of the fluids throughout the domain. In the
simulation, bubble is generated by allowing water-vapour to enter a
cylinder filled with liquid water through an inlet at the bottom. After
the bubble is fully formed, the bubble detaches from the surface and
rises up during which the bubble accelerates due to the net balance
between buoyancy force and viscous drag. Finally when these forces
exactly balance each other, it attains a constant terminal velocity. The
bubble detachment diameter and the terminal velocity of the bubble
are captured by the monitor function provided in FLUENT. The
detachment diameter and the terminal velocity obtained are compared
with the established results based on the shape of the bubble. A good
agreement is obtained between the results obtained from simulation
and the equations in comparison with the established results.
Abstract: This paper focuses on a critical component of the
situational awareness (SA), the control of autonomous vertical flight
for vectored thrust aerial vehicle (VTAV). With the SA strategy, we
proposed a neural network motion control procedure to address the
dynamics variation and performance requirement difference of flight
trajectory for a VTAV. This control strategy with using of NARMAL2
neurocontroller for chosen model of VTAV has been verified by
simulation of take-off and forward maneuvers using software
package Simulink and demonstrated good performance for fast
stabilization of motors, consequently, fast SA with economy in
energy can be asserted during search-and-rescue operations.
Abstract: To construct the lumped spring-mass model
considering the occupants for the offset frontal crash, the SISAME
software and the NHTSA test data were used. The data on 56 kph 40%
offset frontal vehicle to deformable barrier crash test of a MY2007
Mazda 6 4-door sedan were obtained from NHTSA test database. The
overall behaviors of B-pillar and engine of simulation models agreed
very well with the test data. The trends of accelerations at the driver
and passenger head were similar but big differences in peak values.
The differences of peak values caused the large errors of the HIC36
and 3 ms chest g’s. To predict well the behaviors of dummies, the
spring-mass model for the offset frontal crash needs to be improved.