Abstract: This paper deals with a high-order accurate Runge
Kutta Discontinuous Galerkin (RKDG) method for the numerical
solution of the wave equation, which is one of the simple case of a
linear hyperbolic partial differential equation. Nodal DG method is
used for a finite element space discretization in 'x' by discontinuous
approximations. This method combines mainly two key ideas which
are based on the finite volume and finite element methods. The
physics of wave propagation being accounted for by means of
Riemann problems and accuracy is obtained by means of high-order
polynomial approximations within the elements. High order accurate
Low Storage Explicit Runge Kutta (LSERK) method is used for
temporal discretization in 't' that allows the method to be nonlinearly
stable regardless of its accuracy. The resulting RKDG
methods are stable and high-order accurate. The L1 ,L2 and L∞ error
norm analysis shows that the scheme is highly accurate and effective.
Hence, the method is well suited to achieve high order accurate
solution for the scalar wave equation and other hyperbolic equations.
Abstract: Human heart valves diseased by congenital heart
defects, rheumatic fever, bacterial infection, cancer may cause stenosis
or insufficiency in the valves. Treatment may be with medication but
often involves valve repair or replacement (insertion of an artificial
heart valve). Bileaflet mechanical heart valves (BMHVs) are widely
implanted to replace the diseased heart valves, but still suffer from
complications such as hemolysis, platelet activation, tissue
overgrowth and device failure. These complications are closely related
to both flow characteristics through the valves and leaflet dynamics. In
this study, the physiological flow interacting with the moving leaflets
in a bileaflet mechanical heart valve (BMHV) is simulated with a
strongly coupled implicit fluid-structure interaction (FSI) method
which is newly organized based on the Arbitrary-Lagrangian-Eulerian
(ALE) approach and the dynamic mesh method (remeshing) of
FLUENT. The simulated results are in good agreement with previous
experimental studies. This study shows the applicability of the present
FSI model to the complicated physics interacting between fluid flow
and moving boundary.
Abstract: We present a BeeBot, Binus Multi-client Intelligent Telepresence Robot, a custom-build robot system specifically designed for teleconference with multiple person using omni directional actuator. The robot is controlled using a computer networks, so the manager/supervisor can direct the robot to the intended person to start a discussion/inspection. People tracking and autonomous navigation are intelligent features of this robot. We build a web application for controlling the multi-client telepresence robot and open-source teleconference system used. Experimental result presented and we evaluated its performance.
Abstract: The angular distribution of Compton scattering of two
quanta originating in the annihilation of a positron with an electron
is investigated as a quantum key distribution (QKD) mechanism in
the gamma spectral range. The geometry of coincident Compton
scattering is observed on the two sides as a way to obtain partially
correlated readings on the quantum channel. We derive the noise
probability density function of a conceptually equivalent prepare
and measure quantum channel in order to evaluate the limits of the
concept in terms of the device secrecy capacity and estimate it at
roughly 1.9 bits per 1 000 annihilation events. The high error rate
is well above the tolerable error rates of the common reconciliation
protocols; therefore, the proposed key agreement protocol by public
discussion requires key reconciliation using classical error-correcting
codes. We constructed a prototype device based on the readily
available monolithic detectors in the least complex setup.
Abstract: Composite pins of rubber dust collected from tyre
retreading centres of trucks, cars and buses etc.and epoxy with
weight percentages of 10. 15, and 20 % of rubber (weight fractions of
9, 13 and 17 % respectively) have been prepared in house with the
help of a split wooden mould. The pins were tested in a pin-on-disc
wear monitor to determine the co-efficient of friction and weight
losses with varying speeds, loads and time. The wear volume and
wear rates have also been found out for all these three specimens.. It
is observed that all the specimens have exhibited very low coefficient
of friction and low wear rates under dry sliding condition. Out of the
above three samples tested, the specimen with 10 % rubber dust by
weight has shown lowest wear rates. However a peculiar result i.e
decreasing trend has been obtained with 20% reinforcement of rubber
in epoxy while rubbed against steel at varying speeds. This might
have occurred due to high surface finish of the disc and formation of
a thin transfer layer from the composite
Abstract: In this paper, we combine a probabilistic neural method with radial-bias functions in order to construct the lithofacies of the wells DF01, DF02 and DF03 situated in the Triassic province of Algeria (Sahara). Lithofacies is a crucial problem in reservoir characterization. Our objective is to facilitate the experts' work in geological domain and to allow them to obtain quickly the structure and the nature of lands around the drilling. This study intends to design a tool that helps automatic deduction from numerical data. We used a probabilistic formalism to enhance the classification process initiated by a Self-Organized Map procedure. Our system gives lithofacies, from well-log data, of the concerned reservoir wells in an aspect easy to read by a geology expert who identifies the potential for oil production at a given source and so forms the basis for estimating the financial returns and economic benefits.
Abstract: Preparation of size controlled nano-particles of silver catalyst on carbon substrate from e-waste has been investigated. Chemical route was developed by extraction of the metals available in nitric acid followed by treatment with hydrofluoric acid. Silver metal particles deposited with an average size 4-10 nm. A stabilizer concentration of 10- 40 g/l was used. The average size of the prepared silver decreased with increase of the anode current density. Size uniformity of the silver nano-particles was improved distinctly at higher current density no more than 20mA... Grain size increased with EK time whereby aggregation of particles was observed after 6 h of reaction.. The chemical method involves adsorption of silver nitrate on the carbon substrate. Adsorbed silver ions were directly reduced to metal particles using hydrazine hydrate. Another alternative method is by treatment with ammonia followed by heating the carbon loaded-silver hydroxide at 980°C. The product was characterized with the help of XRD, XRF, ICP, SEM and TEM techniques.
Abstract: It has been defined that the “network is the system".
This implies providing levels of service, reliability, predictability and
availability that are commensurate with or better than those that
individual computers provide today. To provide this requires
integrated network management for interconnected networks of
heterogeneous devices covering both the local campus. In this paper
we are addressing a framework to effectively deal with this issue. It
consists of components and interactions between them which are
required to perform the service fault management. A real-world
scenario is used to derive the requirements which have been applied
to the component identification. An analysis of existing frameworks
and approaches with respect to their applicability to the framework is
also carried out.
Abstract: Creativity is often based on an unorthodox
recombination of knowledge; in fact: 80% of all innovations use
given knowledge and put it into a new combination. Cross-industry
innovations follow this way of thinking and bring together problems
and solution ideas from different industries. Therefore analogies and
search strategies have to be developed. Taking this path, the
questions where to search, what to search and how to search have to
be answered. Afterwards, the gathered information can be used
within a planned search process. Identified solution ideas have to be
assessed and analyzed in detail for the success promising adaption
planning.
Abstract: Face and facial expressions play essential roles in
interpersonal communication. Most of the current works on the facial
expression recognition attempt to recognize a small set of the
prototypic expressions such as happy, surprise, anger, sad, disgust
and fear. However the most of the human emotions are
communicated by changes in one or two of discrete features. In this
paper, we develop a facial expressions synthesis system, based on the
facial characteristic points (FCP's) tracking in the frontal image
sequences. Selected FCP's are automatically tracked using a crosscorrelation
based optical flow. The proposed synthesis system uses a
simple deformable facial features model with a few set of control
points that can be tracked in original facial image sequences.
Abstract: In this work, a special case of the image superresolution
problem where the only type of motion is global
translational motion and the blurs are shift-invariant is investigated.
The necessary conditions for exact reconstruction of the original
image by using finite impulse-response reconstruction filters are
developed. Given that the conditions are satisfied, a method for exact
super-resolution is presented and some simulation results are shown.
Abstract: Oilsands bitumen is an extremely important source of
energy for North America. However, due to the presence of large
molecules such as asphaltenes, the density and viscosity of the
bitumen recovered from these sands are much higher than those of
conventional crude oil. As a result the extracted bitumen has to be
diluted with expensive solvents, or thermochemically upgraded in
large, capital-intensive conventional upgrading facilities prior to
pipeline transport. This study demonstrates that globally abundant
natural zeolites such as clinoptilolite from Saint Clouds, New Mexico
and Ca-chabazite from Bowie, Arizona can be used as very effective
reagents for cracking and visbreaking of oilsands bitumen. Natural
zeolite cracked oilsands bitumen products are highly recoverable (up
to ~ 83%) using light hydrocarbons such as pentane, which indicates
substantial conversion of heavier fractions to lighter components.
The resultant liquid products are much less viscous, and have lighter
product distribution compared to those produced from pure thermal
treatment. These natural minerals impart similar effect on industrially
extracted Athabasca bitumen.
Abstract: Ever increasing capacities of contemporary storage devices
inspire the vision to accumulate (personal) information without
the need of deleting old data over a long time-span. Hence the target
of SemanticLIFE project is to create a Personal Information Management
system for a human lifetime data. One of the most important
characteristics of the system is its dedication to retrieve information
in a very efficient way. By adopting user demands regarding the
reduction of ambiguities, our approach aims at a user-oriented and
yet powerful enough system with a satisfactory query performance.
We introduce the query system of SemanticLIFE, the Virtual Query
System, which uses emerging Semantic Web technologies to fulfill
users- requirements.
Abstract: In this paper, the effect of receive and/or transmit
antenna spacing on the performance (BER vs. SNR) of multipleantenna
systems is determined by using an RCS (Radar Cross
Section) channel model. In this physical model, the scatterers
existing in the propagation environment are modeled by their RCS so
that the correlation of the receive signal complex amplitudes, i.e.,
both magnitude and phase, can be estimated. The proposed RCS
channel model is then compared with classical models.
Abstract: In IETF RFC 2002, Mobile-IP was developed to
enable Laptobs to maintain Internet connectivity while moving
between subnets. However, the packet loss that comes from
switching subnets arises because network connectivity is lost while
the mobile host registers with the foreign agent and this encounters
large end-to-end packet delays. The criterion to initiate a simple and
fast full-duplex connection between the home agent and foreign
agent, to reduce the roaming duration, is a very important issue to be
considered by a work in this paper. State-transition Petri-Nets of the
modeling scenario-based CIA: communication inter-agents procedure
as an extension to the basic Mobile-IP registration process was
designed and manipulated to describe the system in discrete events.
The heuristic of configuration file during practical Setup session for
registration parameters, on Cisco platform Router-1760 using IOS
12.3 (15)T and TFTP server S/W is created. Finally, stand-alone
performance simulations from Simulink Matlab, within each subnet
and also between subnets, are illustrated for reporting better end-toend
packet delays. Results verified the effectiveness of our Mathcad
analytical manipulation and experimental implementation. It showed
lower values of end-to-end packet delay for Mobile-IP using CIA
procedure-based early registration. Furthermore, it reported packets
flow between subnets to improve losses between subnets.
Abstract: For lack of the visualization of the ultrasonic detection
method of partial discharge (PD), the ultrasonic detection technology
combined with the X-ray visual detection method (UXV) is proposed.
The method can conduct qualitative analysis accurately and conduct
reliable positioning diagnosis to the internal insulation defects of
GIS, and while it could make up the blindness of the X-ray visual
detection method and improve the detection rate. In this paper, an
experimental model of GIS is used as the trial platform, a variety of
insulation defects are set inside the GIS cavity. With the proposed
method, the ultrasonic method is used to conduct the preliminary
detection, and then the X-ray visual detection is used to locate and
diagnose precisely. Therefore, the proposed UXV technology is
feasible and practical.
Abstract: The presented work is motivated by a French law
regarding nuclear waste management. A new conceptual Accelerator
Driven System (ADS) designed for the Minor Actinides (MA)
transmutation has been assessed by numerical simulation. The
MUltiple Spallation Target (MUST) ADS combines high thermal power (up to 1.4 GWth) and high specific power. A 30 mA and 1
GeV proton beam is divided into three secondary beams transmitted on three liquid lead-bismuth spallation targets. Neutron and thermalhydraulic
simulations have been performed with the code MURE, based on the Monte-Carlo transport code MCNPX. A methodology has been developed to define characteristic of the MUST ADS concept according to a specific transmutation scenario. The reference
scenario is based on a MA flux (neptunium, americium and curium)
providing from European Fast Reactor (EPR) and a plutonium multireprocessing
strategy is accounted for. The MUST ADS reference
concept is a sodium cooled fast reactor. The MA fuel at equilibrium is mixed with MgO inert matrix to limit the core reactivity and
improve the fuel thermal conductivity. The fuel is irradiated over five
years. Five years of cooling and two years for the fuel fabrication are
taken into account. The MUST ADS reference concept burns about 50% of the initial MA inventory during a complete cycle. In term of
mass, up to 570 kg/year are transmuted in one concept. The methodology to design the MUST ADS and to calculate fuel
composition at equilibrium is precisely described in the paper. A detailed fuel evolution analysis is performed and the reference scenario is compared to a scenario where only americium transmutation is performed.
Abstract: At present, it is very common to find renewable
energy resources, especially wind power, connected to distribution
systems. The impact of this wind power on voltage distribution levels
has been addressed in the literature. The majority of this works deals
with the determination of the maximum active and reactive power
that is possible to be connected on a system load bus, until the
voltage at that bus reaches the voltage collapse point. It is done by the
traditional methods of PV curves reported in many references.
Theoretical expression of maximum power limited by voltage
stability transfer through a grid is formulated using an exact
representation of distribution line with ABCD parameters. The
expression is used to plot PV curves at various power factors of a
radial system. Limited values of reactive power can be obtained. This
paper presents a method to study the relationship between the active
power and voltage (PV) at the load bus to identify the voltage
stability limit. It is a foundation to build a permitted working
operation region in complying with the voltage stability limit at the
point of common coupling (PCC) connected wind farm.
Abstract: Traditionally, Internet has provided best-effort service to every user regardless of its requirements. However, as Internet becomes universally available, users demand more bandwidth and applications require more and more resources, and interest has developed in having the Internet provide some degree of Quality of Service. Although QoS is an important issue, the question of how it will be brought into the Internet has not been solved yet. Researches, due to the rapid advances in technology are proposing new and more desirable capabilities for the next generation of IP infrastructures. But neither all applications demand the same amount of resources, nor all users are service providers. In this way, this paper is the first of a series of papers that presents an architecture as a first step to the optimization of QoS in the Internet environment as a solution to a SMSE's problem whose objective is to provide public service to internet with certain Quality of Service expectations. The service provides new business opportunities, but also presents new challenges. We have designed and implemented a scalable service framework that supports adaptive bandwidth based on user demands, and the billing based on usage and on QoS. The developed application has been evaluated and the results show that traffic limiting works at optimum and so it does exceeding bandwidth distribution. However, some considerations are done and currently research is under way in two basic areas: (i) development and testing new transfer protocols, and (ii) developing new strategies for traffic improvements based on service differentiation.
Abstract: Multi-Radio Multi-Channel Wireless Mesh Networks (MRMC-WMNs) operate at the backbone to access and route high volumes of traffic simultaneously. Such roles demand high network capacity, and long “online" time at the expense of accelerated transmission energy depletion and poor connectivity. This is the problem of transmission power control. Numerous power control methods for wireless networks are in literature. However, contributions towards MRMC configurations still face many challenges worth considering. In this paper, an energy-efficient power selection protocol called PMMUP is suggested at the Link-Layer. This protocol first divides the MRMC-WMN into a set of unified channel graphs (UCGs). A UCG consists of multiple radios interconnected to each other via a common wireless channel. In each UCG, a stochastic linear quadratic cost function is formulated. Each user minimizes this cost function consisting of trade-off between the size of unification states and the control action. Unification state variables come from independent UCGs and higher layers of the protocol stack. The PMMUP coordinates power optimizations at the network interface cards (NICs) of wireless mesh routers. The proposed PMMUP based algorithm converges fast analytically with a linear rate. Performance evaluations through simulations confirm the efficacy of the proposed dynamic power control.