Abstract: Microscopic simulation tool kits allow for
consideration of the two processes of railway operations and the
previous timetable production. Block occupation conflicts on both
process levels are often solved by using defined train priorities. These
conflict resolutions (dispatching decisions) generate reactionary
delays to the involved trains. The sum of reactionary delays is
commonly used to evaluate the quality of railway operations, which
describes the timetable robustness. It is either compared to an
acceptable train performance or the delays are appraised
economically by linear monetary functions. It is impossible to
adequately evaluate dispatching decisions without a well-founded
objective function. This paper presents a new approach for the
evaluation of dispatching decisions. The approach uses mode choice
models and considers the behaviour of the end-customers. These
models evaluate the reactionary delays in more detail and consider
other competing modes of transport. The new approach pursues the
coupling of a microscopic model of railway operations with the
macroscopic choice mode model. At first, it will be implemented for
railway operations process but it can also be used for timetable
production. The evaluation considers the possibility for the customer
to interchange to other transport modes. The new approach starts to
look at rail and road, but it can also be extended to air travel. The
result of mode choice models is the modal split. The reactions by the
end-customers have an impact on the revenue of the train operating
companies. Different purposes of travel have different payment
reserves and tolerances towards late running. Aside from changes to
revenues, longer journey times can also generate additional costs.
The costs are either time- or track-specific and arise from required
changes to rolling stock or train crew cycles. Only the variable values
are summarised in the contribution margin, which is the base for the
monetary evaluation of delays. The contribution margin is calculated
for different possible solutions to the same conflict. The conflict
resolution is optimised until the monetary loss becomes minimal. The
iterative process therefore determines an optimum conflict resolution
by monitoring the change to the contribution margin. Furthermore, a
monetary value of each dispatching decision can also be derived.
Abstract: In more complex systems, such as automotive
gearbox, a rigorous treatment of the data is necessary because there
are several moving parts (gears, bearings, shafts, etc.), and in this
way, there are several possible sources of errors and also noise. The
basic objective of this work is the detection of damage in automotive
gearbox. The detection methods used are the wavelet method, the
bispectrum; advanced filtering techniques (selective filtering) of
vibrational signals and mathematical morphology. Gearbox vibration
tests were performed (gearboxes in good condition and with defects)
of a production line of a large vehicle assembler. The vibration
signals are obtained using five accelerometers in different positions
of the sample. The results obtained using the kurtosis, bispectrum,
wavelet and mathematical morphology showed that it is possible to
identify the existence of defects in automotive gearboxes.
Abstract: High density electrical prospecting has been widely
used in groundwater investigation, civil engineering and
environmental survey. For efficient inversion, the forward modeling
routine, sensitivity calculation, and inversion algorithm must be
efficient. This paper attempts to provide a brief summary of the past
and ongoing developments of the method. It includes reviews of the
procedures used for data acquisition, processing and inversion of
electrical resistivity data based on compilation of academic literature.
In recent times there had been a significant evolution in field survey
designs and data inversion techniques for the resistivity method. In
general 2-D inversion for resistivity data is carried out using the
linearized least-square method with the local optimization technique
.Multi-electrode and multi-channel systems have made it possible to
conduct large 2-D, 3-D and even 4-D surveys efficiently to resolve
complex geological structures that were not possible with traditional
1-D surveys. 3-D surveys play an increasingly important role in very
complex areas where 2-D models suffer from artifacts due to off-line
structures. Continued developments in computation technology, as
well as fast data inversion techniques and software, have made it
possible to use optimization techniques to obtain model parameters to
a higher accuracy. A brief discussion on the limitations of the
electrical resistivity method has also been presented.
Abstract: This paper is aimed to the use of different types of
industrial wastes in concrete production. From examined waste
(crushed concrete waste) our tested concrete samples with dimension
150 mm were prepared. In these samples, fractions 4/8 mm and 8/16
mm by recycled concrete aggregate with a range of variation from 0
to 100% were replaced. Experiment samples were tested for
compressive strength after 2, 7, 14 and 28 days of hardening.
From obtained results it is evident that all samples prepared with
washed recycled concrete aggregates met the requirement of standard
for compressive strength of 20 MPa already after 14 days of
hardening. Sample prepared with recycled concrete aggregates (4/8
mm: 100% and 8/16 mm: 60%) reached 101% of compressive
strength value (34.7 MPa) after 28 days of hardening in comparison
with the reference sample (34.4 MPa). The lowest strength after 28
days of hardening (27.42 MPa) was obtained for sample consisting of
recycled concrete in proportion of 40% for 4/8 fraction and 100% for
8/16 fraction of recycled concrete.
Abstract: In this work, two fermentations at different
temperatures (25 and 30ºC), with cell recycling, were accomplished
to produce ethanol, using a mix of commercial substrates, xylose
(70%) and glucose (30%), as organic source for Scheffersomyces
stipitis. Five consecutive fermentations of 80 g L-1 (1º, 2º and 3º
recycles), 96 g L-1 (4º recycle) and 120 g L-1 (5º recycle)reduced
sugars led to a final maximum ethanol concentration of 17.2 and 34.5
g L-1, at 25 and 30ºC, respectively. Glucose was the preferred
substrate; moreover xylose startup degradation was initiated after a
remaining glucose presence in the medium. Results showed that yeast
acid treatment, performed before each cycle, provided improvements
on cell viability, accompanied by ethanol productivity of 2.16 g L-1 h-
1 at 30ºC. A maximum 36% of xylose was retained in the
fermentation medium and after five-cycle fermentation an ethanol
yield of 0.43 g ethanol/g sugars was observed. S. stipitis fermentation
capacity and tolerance showed better results at 30ºC with 83.4% of
theoretical yield referenced on initial biomass.
Abstract: In this paper we propose a novel methodology for
extracting a road network and its nodes from satellite images of
Algeria country.
This developed technique is a progress of our previous research
works. It is founded on the information theory and the mathematical
morphology; the information theory and the mathematical
morphology are combined together to extract and link the road
segments to form a road network and its nodes.
We therefore have to define objects as sets of pixels and to study
the shape of these objects and the relations that exist between them.
In this approach, geometric and radiometric features of roads are
integrated by a cost function and a set of selected points of a crossing
road. Its performances were tested on satellite images of Algeria
country.
Abstract: Hypersonic flows around spatial vehicles during their reentry phase in planetary atmospheres are characterized by intense aerothermodynamics phenomena. The aim of this work is to analyze high temperature flows around an axisymmetric blunt body taking into account chemical and vibrational non-equilibrium for air mixture species and the no slip condition at the wall. For this purpose, the Navier-Stokes equations system is resolved by the finite volume methodology to determine the flow parameters around the axisymmetric blunt body especially at the stagnation point and in the boundary layer along the wall of the blunt body. The code allows the capture of shock wave before a blunt body placed in hypersonic free stream. The numerical technique uses the Flux Vector Splitting method of Van Leer. CFL coefficient and mesh size level are selected to ensure the numerical convergence.
Abstract: Structural Equation Modeling (SEM) was used to test
a hypothesized model explaining Malaysian hypermarket customers’
perceptions of brand trust (BT), customer perceived value (CPV) and
perceived service quality (PSQ) on building their brand loyalty
(CBL) and generating positive word-of-mouth communication
(WOM). Self-administered questionnaires were used to collect data
from 374 Malaysian hypermarket customers from Mydin, Tesco,
Aeon Big and Giant in Kuala Lumpur, a metropolitan city of
Malaysia. The data strongly supported the model exhibiting that BT,
CPV and PSQ are prerequisite factors in building customer brand
loyalty, while PSQ has the strongest effect on prediction of customer
brand loyalty compared to other factors. Besides, the present study
suggests the effect of the aforementioned factors via customer brand
loyalty strongly contributes to generate positive word of mouth
communication.
Abstract: This paper presents the development of a robot car
that can track the motion of an object by detecting its color through
an Android device. The employed computer vision algorithm uses the
OpenCV library, which is embedded into an Android application of a
smartphone, for manipulating the captured image of the object. The
captured image of the object is subjected to color conversion and is
transformed to a binary image for further processing after color
filtering. The desired object is clearly determined after removing
pixel noise by applying image morphology operations and contour
definition. Finally, the area and the center of the object are
determined so that object’s motion to be tracked. The smartphone
application has been placed on a robot car and transmits by Bluetooth
to an Arduino assembly the motion directives so that to follow
objects of a specified color. The experimental evaluation of the
proposed algorithm shows reliable color detection and smooth
tracking characteristics.
Abstract: This paper adopts a two-stage data envelopment
analysis to explore the impacts of financial development and bank
operating scale on bank efficiencies. The sample comprises
unbalanced panel data of 32 Taiwanese listed domestic commercial
banks over the period 1998 to 2013. Empirical results show that pure
technical efficiency is positively related to financial development,
whereas the effect of financial development on scale efficiency is
insignificant. Enlargement of bank operating scale improves bank
efficiencies, but the efficiency gains are decreased gradually when the
scale increases. Increases in capital adequacy ratio and market power
of loans lead into a growth of bank efficiencies.
Abstract: In the present study, the kinetics of thermal
degradation of a phenolic and lignin reinforced phenolic foams, and
the lignin used as reinforcement were studied and the activation
energies of their degradation processes were obtained by a DAEM
model. The average values for five heating rates of the mean
activation energies obtained were: 99.1, 128.2, and 144.0 kJ.mol-1 for
the phenolic foam; 109.5, 113.3, and 153.0 kJ.mol-1 for the lignin
reinforcement; and 82.1, 106.9, and 124.4 kJ.mol-1 for the lignin
reinforced phenolic foam. The standard deviation ranges calculated
for each sample were 1.27-8.85, 2.22-12.82, and 3.17-8.11 kJ.mol-1
for the phenolic foam, lignin and the reinforced foam, respectively.
The DAEM model showed low mean square errors (
Abstract: With the growing of computer and network, digital
data can be spread to anywhere in the world quickly. In addition,
digital data can also be copied or tampered easily so that the security
issue becomes an important topic in the protection of digital data.
Digital watermark is a method to protect the ownership of digital data.
Embedding the watermark will influence the quality certainly. In this
paper, Vector Quantization (VQ) is used to embed the watermark into
the image to fulfill the goal of data hiding. This kind of watermarking
is invisible which means that the users will not conscious the existing
of embedded watermark even though the embedded image has tiny
difference compared to the original image. Meanwhile, VQ needs a lot
of computation burden so that we adopt a fast VQ encoding scheme by
partial distortion searching (PDS) and mean approximation scheme to
speed up the data hiding process.
The watermarks we hide to the image could be gray, bi-level and
color images. Texts are also can be regarded as watermark to embed.
In order to test the robustness of the system, we adopt Photoshop to
fulfill sharpen, cropping and altering to check if the extracted
watermark is still recognizable. Experimental results demonstrate that
the proposed system can resist the above three kinds of tampering in
general cases.
Abstract: Ibeno, Nigeria hosts the operational base of Mobil
Producing Nigeria Unlimited (MPNU), a subsidiary of ExxonMobil
and the current highest oil & condensate producer in Nigeria. Besides
MPNU, other oil companies operate onshore, on the continental shelf
and deep offshore of the Atlantic Ocean in Ibeno, Nigeria. This study
was designed to delineate oil polluted sites in Ibeno, Nigeria using
geophysical methods of electrical resistivity (ER) and ground
penetrating radar (GPR). Results obtained revealed that there have
been hydrocarbon contaminations of this environment by past crude
oil spills as observed from high resistivity values and GPR profiles
which clearly show the distribution, thickness and lateral extent of
hydrocarbon contamination as represented on the radargram reflector
tones. Contaminations were of varying degrees, ranging from slight
to high, indicating levels of substantial attenuation of crude oil
contamination over time. Moreover, the display of relatively lower
resistivities of locations outside the impacted areas compared to
resistivity values within the impacted areas and the 3-D Cartesian
images of oil contaminant plume depicted by red, light brown and
magenta for high, low and very low oil impacted areas, respectively
confirmed significant recent pollution of the study area with crude
oil.
Abstract: The seismic risk mitigation from the perspective of
the old buildings stock is truly essential in Algerian urban areas,
particularly those located in seismic prone regions, such as Annaba
city, and which the old buildings present high levels of degradation
associated with no seismic strengthening and/or rehabilitation
concerns. In this sense, the present paper approaches the issue of the
seismic vulnerability assessment of old masonry building stocks
through the adaptation of a simplified methodology developed for a
European context area similar to that of Annaba city, Algeria.
Therefore, this method is used for the first level of seismic
vulnerability assessment of the masonry buildings stock of the old
city center of Annaba. This methodology is based on a vulnerability
index that is suitable for the evaluation of damage and for the
creation of large-scale loss scenarios. Over 380 buildings were
evaluated in accordance with the referred methodology and the
results obtained were then integrated into a Geographical Information
System (GIS) tool. Such results can be used by the Annaba city
council for supporting management decisions, based on a global view
of the site under analysis, which led to more accurate and faster
decisions for the risk mitigation strategies and rehabilitation plans.
Abstract: Pt/γ-Al2O3 membrane catalysts were prepared via an
evaporative-crystallization deposition method. The obtained Pt/γ-
Al2O3 catalyst activity was tested after characterization (SEM-EDAX
observation, BET measurement, permeability assessment) in the
catalytic oxidation of selected volatile organic compound (VOC) i.e.
propane, fed in mixture of oxygen. The VOC conversion (nearly
90%) obtained by varying the operating temperature showed that
flow-through membrane reactor might do better in the abatement of
VOCs.
Abstract: This paper analyzes the conceptual framework of three
statistical methods, multiple regression, path analysis, and structural
equation models. When establishing research model of the statistical
modeling of complex social phenomenon, it is important to know the
strengths and limitations of three statistical models. This study
explored the character, strength, and limitation of each modeling and
suggested some strategies for accurate explaining or predicting the
causal relationships among variables. Especially, on the studying of
depression or mental health, the common mistakes of research
modeling were discussed.
Abstract: An unconventional composite inorganic ceramic
membrane capable of enhancing carbon dioxide emission decline was
fabricated and tested at laboratory scale in conformism to various
environmental guidelines and also to mitigate the effect of global
warming. A review of the existing membrane technologies for carbon
capture including the relevant gas transport mechanisms is presented.
Single gas permeation experiments using silica modified ceramic
membrane with internal diameter 20mm, outside diameter 25mm and
length of 368mm deposited on a macro porous support was carried
out to investigate individual gas permeation behaviours at different
pressures at room temperature. Membrane fabrication was achieved
using after a dip coating method. Nitrogen, Carbon dioxide, Argon,
Oxygen and Methane pure gases were used to investigate their
individual permeation rates at various pressures. Results show that
the gas flow rate increases with pressure drop. However above a
pressure of 3bar, CO2 permeability ratio to that of the other gases
indicated control of a more selective surface adsorptive transport
mechanism.
Abstract: Polymer Electrolyte Membrane Fuel Cell (PEMFC) is
such a time-vary nonlinear dynamic system. The traditional linear
modeling approach is hard to estimate structure correctly of PEMFC
system. From this reason, this paper presents a nonlinear modeling of
the PEMFC using Neural Network Auto-regressive model with
eXogenous inputs (NNARX) approach. The multilayer perception
(MLP) network is applied to evaluate the structure of the NNARX
model of PEMFC. The validity and accuracy of NNARX model are
tested by one step ahead relating output voltage to input current from
measured experimental of PEMFC. The results show that the obtained
nonlinear NNARX model can efficiently approximate the dynamic
mode of the PEMFC and model output and system measured output
consistently.
Abstract: Design concepts of real-time embedded system can be
realized initially by introducing novel design approaches. In this
literature, model based design approach and in-the-loop testing were
employed early in the conceptual and preliminary phase to formulate
design requirements and perform quick real-time verification. The
design and analysis methodology includes simulation analysis, model
based testing, and in-the-loop testing. The design of conceptual driveby-
wire, or DBW, algorithm for electronic control unit, or ECU, was
presented to demonstrate the conceptual design process, analysis, and
functionality evaluation. The concepts of DBW ECU function can be
implemented in the vehicle system to improve electric vehicle, or EV,
conversion drivability. However, within a new development process,
conceptual ECU functions and parameters are needed to be evaluated.
As a result, the testing system was employed to support conceptual
DBW ECU functions evaluation. For the current setup, the system
components were consisted of actual DBW ECU hardware, electric
vehicle models, and control area network or CAN protocol. The
vehicle models and CAN bus interface were both implemented as
real-time applications where ECU and CAN protocol functionality
were verified according to the design requirements. The proposed
system could potentially benefit in performing rapid real-time
analysis of design parameters for conceptual system or software
algorithm development.
Abstract: The aim of this research is to identify the key factors in shipping company’s port selection in order to providing their requirement. To identify and rank factors that play the main role in selecting port for providing the ship requirement, at the first step, data were collected via Semi-structured interviews, the aim was to generate knowledge on how shipping company select the port and suppliers for providing their needs. 37 port selection factors were chosen from the previous researches and field interviews and have been categorized into two groups of port's factor and the factors of services of suppliers companies. The current study adopts a questionnaire survey to the main shipping companies' operators in Iran. Their responses reveal that level of services of supplying companies and customs rules play the important role in selecting the ports. Our findings could affect decisions made by port authorities to consider that supporting the privet sections for ship chandelling business could have the best result in attracting ships.