Abstract: In the present paper, we propose numerical methods for solving the Stein equation AXC - X - D = 0 where the matrix A is large and sparse. Such problems appear in discrete-time control problems, filtering and image restoration. We consider the case where the matrix D is of full rank and the case where D is factored as a product of two matrices. The proposed methods are Krylov subspace methods based on the block Arnoldi algorithm. We give theoretical results and we report some numerical experiments.
Abstract: In recent past, the Unified Modeling Language (UML) has become the de facto industry standard for object-oriented modeling of the software systems. The syntax and semantics rich UML has encouraged industry to develop several supporting tools including those capable of generating deployable product (code) from the UML models. As a consequence, ensuring the correctness of the model/design has become challenging and extremely important task. In this paper, we present an approach for automatic verification of protocol model/design. As a case study, Session Initiation Protocol (SIP) design is verified for the property, “the CALLER will not converse with the CALLEE before the connection is established between them ". The SIP is modeled using UML statechart diagrams and the desired properties are expressed in temporal logic. Our prototype verifier “UML-SMV" is used to carry out the verification. We subjected an erroneous SIP model to the UML-SMV, the verifier could successfully detect the error (in 76.26ms) and generate the error trace.
Abstract: One of the main research methods in humanistic studies is the collection and process of data through questionnaires. This paper reports our experiences of localizing and adapting the phpESP package of electronic surveys, which led to a friendly on-line questionnaire environment offered through our department web site. After presenting the characteristics of this environment, we identify the expected benefits and present a questionnaire carried out through both the traditional and electronic way. We present the respondents' feedback and then we report the researchers' opinions.Finally, we propose ideas we intend to implement in order to further assist and enhance the research based on this web accessed,electronic questionnaire environment.
Abstract: Minor problems arising from optimizations by
welding of fixed prostheses frameworks can be identified by
macroscopic and microscopic visual inspection. The purpose of this
study was to highlight the visible discontinuities present in the laser
welds of dental Ni-Cr alloys. Ni-Cr base metal alloys designated for
fixed prostheses manufacture were selected for the experiments.
Using cast plates, preliminary tests were conducted by laser welding.
Macroscopic visual inspection was done carefully to assess the
defects of the welding rib. Electron microscopy images allowed
visualization of small discontinuities, which escapes visual
inspection. Making comparison to Ni-Cr alloys taken in the
experiment and laser welded, after visual analysis, the best welds
appear for Heraenium NA alloy.
Abstract: Restarted GMRES methods augmented with approximate eigenvectors are widely used for solving large sparse linear systems. Recently a new scheme of augmenting with error approximations is proposed. The main aim of this paper is to develop a restarted GMRES method augmented with the combination of harmonic Ritz vectors and error approximations. We demonstrate that the resulted combination method can gain the advantages of two approaches: (i) effectively deflate the small eigenvalues in magnitude that may hamper the convergence of the method and (ii) partially recover the global optimality lost due to restarting. The effectiveness and efficiency of the new method are demonstrated through various numerical examples.
Abstract: This research attempts to study the feasibility of
augmenting an augmented reality (AR) image card on a Quick
Response (QR) code. The authors have developed a new visual tag,
which contains a QR code and an augmented AR image card. The new
visual tag has features of reading both of the revealed data of the QR
code and the instant data from the AR image card. Furthermore, a
handheld communicating device is used to read and decode the new
visual tag, and then the concealed data of the new visual tag can be
revealed and read through its visual display. In general, the QR code is
designed to store the corresponding data or, as a key, to access the
corresponding data from the server through internet. Those reveled
data from the QR code are represented in text. Normally, the AR
image card is designed to store the corresponding data in
3-Dimensional or animation/video forms. By using QR code's
property of high fault tolerant rate, the new visual tag can access those
two different types of data by using a handheld communicating device.
The new visual tag has an advantage of carrying much more data than
independent QR code or AR image card. The major findings of this
research are: 1) the most efficient area for the designed augmented AR
card augmenting on the QR code is 9% coverage area out of the total
new visual tag-s area, and 2) the best location for the augmented AR
image card augmenting on the QR code is located in the bottom-right
corner of the new visual tag.
Abstract: This paper presents a novel sinusoidal modulation
scheme that features least correlated noise and high linearity. The
modulation circuit, which is composed of a quantizer, a resonator, and
a comparator, is capable of eliminating correlated modulation noise
while doing modulation. The proposed modulation scheme combined
with the linear quadratic optimal control is applied to a single-phase
voltage source inverter and validated with the experiment results. The
experiments show that the inverter supplies stable 60Hz 110V AC
power with a total harmonic distortion of less than 1%, under the DC
input variation from 190 V to 300 V and the output power variation
from 0 to 600 W.
Abstract: In this paper a fast motion estimation method for
H.264/AVC named Triplet Search Motion Estimation (TS-ME) is
proposed. Similar to some of the traditional fast motion estimation
methods and their improved proposals which restrict the search points
only to some selected candidates to decrease the computation
complexity, proposed algorithm separate the motion search process to
several steps but with some new features. First, proposed algorithm try
to search the real motion area using proposed triplet patterns instead of
some selected search points to avoid dropping into the local minimum.
Then, in the localized motion area a novel 3-step motion search
algorithm is performed. Proposed search patterns are categorized into
three rings on the basis of the distance from the search center. These
three rings are adaptively selected by referencing the surrounding
motion vectors to early terminate the motion search process. On the
other hand, computation reduction for sub pixel motion search is also
discussed considering the appearance probability of the sub pixel
motion vector. From the simulation results, motion estimation speed
improved by a factor of up to 38 when using proposed algorithm than
that of the reference software of H.264/AVC with ignorable picture
quality loss.
Abstract: The colors of the human skin represent a special
category of colors, because they are distinctive from the colors of
other natural objects. This category is found as a cluster in color
spaces, and the skin color variations between people are mostly due
to differences in the intensity. Besides, the face detection based on
skin color detection is a faster method as compared to other
techniques. In this work, we present a system to track faces by
carrying out skin color detection in four different color spaces: HSI,
YCbCr, YES and RGB. Once some skin color regions have been
detected for each color space, we label each and get some
characteristics such as size and position. We are supposing that a face
is located in one the detected regions. Next, we compare and employ
a polling strategy between labeled regions to determine the final
region where the face effectively has been detected and located.
Abstract: Double-diffusive natural convection in an open top
square cavity and heated from the side is studied numerically.
Constant temperatures and concentration are imposed along the right
and left walls while the heat balance at the surface is assumed to obey
Newton-s law of cooling. The finite difference method is used to
solve the dimensionless governing equations. The numerical results
are reported for the effect of Marangoni number, Biot number and
Prandtl number on the contours of streamlines, temperature and
concentration. The predicted results for the average Nusselt number
and Sherwood number are presented for various parametric
conditions. The parameters involved are as follows; the thermal
Marangoni number, 0 ≤ MaT ≤1000 , the solutal Marangoni number,
0 1000 c ≤ Ma ≤ , the Biot number, 0 ≤ Bi ≤ 6 , Grashof number,
5 Gr = 10 and aspect ratio 1. The study focused on both flows; thermal
dominated, N = 0.8 , and compositional dominated, N = 1.3 .
Abstract: The effects of ethylene (C2H4) feed position and
O2/C2H4 feed molar ratio on ethylene epoxidation in a parallel
dielectric barrier discharge (DBD) were studied. The results showed
that the ethylene feed position fraction of 0.5 and the feed molar
ratio of O2/C2H4 of 0.2:1 gave the highest EO selectivity of 34.3%
and the highest EO yield of 5.28% with low power consumptions of
2.11×10-16 Ws/molecule of ethylene converted and 6.34×10-16
Ws/molecule of EO produced when the DBD system was operated
under the best conditions: an applied voltage of 19 kV, an input
frequency of 500 Hz and a total feed flow rate of 50 cm3/min. The
separate ethylene feed system provided much higher epoxidation
activity as compared to the mixed feed system which gave EO
selectivity of 15.5%, EO yield of 2.1% and the power consumption of
EO produced of 7.7×10-16 Ws/molecule.
Abstract: Double-diffusive steady convection in a partially
porous cavity with partially permeable walls and under the combined
buoyancy effects of thermal and mass diffusion was analysed
numerically using finite volume method.
The top wall is well insulated and impermeable while the bottom
surface is partially well insulated and impermeable and partially
submitted to constant temperature T1 and concentration C1. Constant
equal temperature T2 and concentration C2 are imposed along the
vertical surfaces of the enclosure. Mass suction/injection and
injection/suction are respectively considered at the bottom of the
porous centred partition and at one of the vertical walls.
Heat and mass transfer characteristics as streamlines and average
Nusselt numbers and Sherwood numbers were discussed for different
values of buoyancy ratio, Rayleigh number, and injection/suction
coefficient.
It is especially noted that increasing the injection factor
disadvantages the exchanges in the case of the injection while the
transfer is augmented in case of suction. On the other hand, a critical
value of the buoyancy ratio was highlighted for which heat and mass
transfers are minimized.
Abstract: A new numerical method for solving the twodimensional,
steady, incompressible, viscous flow equations on a
Curvilinear staggered grid is presented in this paper. The proposed
methodology is finite difference based, but essentially takes
advantage of the best features of two well-established numerical
formulations, the finite difference and finite volume methods. Some
weaknesses of the finite difference approach are removed by
exploiting the strengths of the finite volume method. In particular,
the issue of velocity-pressure coupling is dealt with in the proposed
finite difference formulation by developing a pressure correction
equation in a manner similar to the SIMPLE approach commonly
used in finite volume formulations. However, since this is purely a
finite difference formulation, numerical approximation of fluxes is
not required. Results obtained from the present method are based on
the first-order upwind scheme for the convective terms, but the
methodology can easily be modified to accommodate higher order
differencing schemes.
Abstract: The main objective of seismic rehabilitation in the
foundations is decreasing the range of horizontal and vertical
vibrations and omitting high frequencies contents under the seismic
loading. In this regard, the advantages of micropiles network is
utilized. Reduction in vibration range of foundation can be achieved
by using high dynamic rigidness module such as deep foundations. In
addition, natural frequency of pile and soil system increases in regard
to rising of system rigidness. Accordingly, the main strategy is
decreasing of horizontal and vertical seismic vibrations of the
structure. In this case, considering the impact of foundation, pile and
improved soil foundation is a primary concern. Therefore, in this
paper, effective factors are studied on the seismic rehabilitation of
foundations applying network micropiles in sandy soils with
nonlinear reaction.
Abstract: In this paper we present a novel technique for data
hiding in binary document images. We use the concept of entropy in
order to identify document specific least distortive areas throughout
the binary document image. The document image is treated as any
other image and the proposed method utilizes the standard document
characteristics for the embedding process. Proposed method
minimizes perceptual distortion due to embedding and allows
watermark extraction without the requirement of any side information
at the decoder end.
Abstract: The problem discussed in this paper involves packing fresh fish fileet of the northern Cod into a standard square container. The fish is first cleaned and split and then collected on a belt ready to be stacked in a container. The aim of our work is to pack the fish into the container with constraints on the amount of overlap allowed for the fileets. The current focus is to design a packing cell that can be real-time and of practical use, while finding the optimal solution to the degree of overlap and minimise the unused space of the container.
Abstract: A laboratory set-up was designed to survey the
effectiveness of UV/O3 advanced oxidation process (AOP) for the
removal of Carbaryl from polluted water in batch reactor. The study
was carried out by UV/O3 process for water samples containing 1 to
20 mg/L of Carbaryl in distilled water. Also the range of drinking
water resources adjusted in synthetic water and effects of contact
time, pH and Carbaryl concentration were studied. The residual
pesticide concentration was determined by applying high
performance liquid chromatography (HPLC). The results indicated
that increasing of retention time and pH, enhances pesticide removal
efficiency. The removal efficiency has been affected by pesticide
initial concentration. Samples with low pesticide concentration
showed a remarkable removal efficiency compared to the samples
with high pesticide concentration. AOP method showed the removal
efficiencies of 80% to 100%. Although process showed high
performance for removal of pesticide from water samples, this
process has different disadvantages including complication,
intolerability, difficulty of maintenance and equipmental and
structural requirements.
Abstract: Walking and sit to stand are activities carried out by
all the people many times during the day, but physical disabilities due
to age and diseases create needs of assistive devices to help elderly
people during their daily life. This study aims to study the different
types and mechanisms of the assistive devices. We will analyze the
limitations and the challenges faced by the researchers in this field.
We will introduce the Assistive Device developed at the Egypt-Japan
University of Science and Technology, named E-JUST Assistive
Device (EJAD). EJAD will be a low cost intelligent assistive device
to help elders in walking and sit-to-stand activities.
Abstract: In the present study, Convective heat transfer
coefficient and pressure drop of Al2O3/water nanofluid in laminar
flow regime under constant heat flux conditions inside a circular tube
were experimentally investigated. Al2O3/water nanofluid with 0.5%
and 1% volume concentrations with 15 nm diameter nanoparticles
were used as working fluid. The effect of different volume
concentrations on convective heat transfer coefficient and friction
factor was studied. The results emphasize that increasing of particle
volume concentration leads to enhance convective heat transfer
coefficient. Measurements show the average heat transfer coefficient
enhanced about 11-20% with 0.5% volume concentration and
increased about 16-27% with 1% volume concentration compared to
distilled water. In addition, the convective heat transfer coefficient of
nanofluid enhances with increase in heat flux. From the results, the
average ratio of (fnf/fbf) was about 1.10 for 0.5% volume
concentration. Therefore, there is no significant increase in friction
factor for nanofluids.
Abstract: Sustainable energy usage has been recognized as one
of the important measure to increase the competitiveness of the
nation globally. Many strong emphases were given in the Ninth
Malaysia Plan (RMK9) to improve energy efficient especially to
government buildings. With this in view, a project to investigate the
potential of energy saving in selected building in Universiti Tun
Hussein Onn Malaysia (UTHM) was carried out. In this project, a
case study involving electric energy consumption of the academic
staff office building was conducted. The scope of the study include to
identify energy consumption in a selected building, to study energy
saving opportunities, to analyse cost investment in term of economic
and to identify users attitude with respect to energy usage. The
MS1525:2001, Malaysian Standard -Code of practice on energy
efficiency and use of renewable energy for non-residential buildings
was used as reference. Several energy efficient measures were
considered and their merits and priority were compared. Improving
human behavior can reduce energy consumption by 6% while
technical measure can reduce energy consumption by 44%. Two
economic analysis evaluation methods were applied; they are the
payback period method and net present value method.