Abstract: Infrared communication in the wavelength band 780-
950 nm is very suitable for short-range point-to-point communications.
It is a good choice for vehicle-to-vehicle communication in several
intelligent-transportation-system (ITS) applications such as cooperative
driving, collision warning, and pileup-crash prevention. In this
paper, with the aid of a physical model established in our previous
works, we explore the communication area of an infrared intervehicle
communication system utilizing a typical low-cost cormmercial lightemitting
diodes (LEDs) as the emitter and planar p-i-n photodiodes
as the receiver. The radiation pattern of the emitter fabricated by
aforementioned LEDs and the receiving pattern of the receiver are
approximated by a linear combination of cosinen functions. This
approximation helps us analyze the system performance easily. Both
multilane straight-road conditions and curved-road conditions with
various radius of curvature are taken into account. The condition of
a small car communicating with a big truck, i.e., there is a vertical
mounting height difference between the emitter and the receiver, is
also considered. Our results show that the performance of the system
meets the requirement of aforementioned ITS applications in terms
of the communication area.
Abstract: Speed sensorless systems are intensively studied during recent years; this is mainly due to their economical benefit and fragility of mechanical sensors and also the difficulty of installing this type of sensor in many applications. These systems suffer from instability problems and sensitivity to parameter mismatch at low speed operation. In this paper an analysis of adaptive observer stability with stator resistance estimation is given.
Abstract: Over the past years, the EMCCD has had a profound
influence on photon starved imaging applications relying on its unique
multiplication register based on the impact ionization effect in the
silicon. High signal-to-noise ratio (SNR) means high image quality.
Thus, SNR improvement is important for the EMCCD. This work
analyzes the SNR performance of an EMCCD with gain off and on. In
each mode, simplified SNR models are established for different
integration times. The SNR curves are divided into readout noise (or
CIC) region and shot noise region by integration time. Theoretical
SNR values comparing long frame integration and frame adding in
each region are presented and discussed to figure out which method is
more effective. In order to further improve the SNR performance,
pixel binning is introduced into the EMCCD. The results show that
pixel binning does obviously improve the SNR performance, but at the
expensive of the spatial resolution.
Abstract: This paper presents a new spread-spectrum
watermarking algorithm for digital images in discrete wavelet
transform (DWT) domain. The algorithm is applied for embedding
watermarks like patient identification /source identification or
doctors signature in binary image format into host digital
radiological image for potential telemedicine applications.
Performance of the algorithm is analysed by varying the gain factor,
subband decomposition levels, and size of watermark. Simulation
results show that the proposed method achieves higher watermarking
capacity.
Abstract: Real-time 3D applications have to guarantee
interactive rendering speed. There is a restriction for the number of
polygons which is rendered due to performance of a graphics hardware
or graphics algorithms. Generally, the rendering performance will be
drastically increased when handling only the dynamic 3d models,
which is much fewer than the static ones. Since shapes and colors of
the static objects don-t change when the viewing direction is fixed, the
information can be reused. We render huge amounts of polygon those
cannot handled by conventional rendering techniques in real-time by
using a static object image and merging it with rendering result of the
dynamic objects. The performance must be decreased as a
consequence of updating the static object image including removing
an static object that starts to move, re-rending the other static objects
being overlapped by the moving ones. Based on visibility of the object
beginning to move, we can skip the updating process. As a result, we
enhance rendering performance and reduce differences of rendering
speed between each frame. Proposed method renders total
200,000,000 polygons that consist of 500,000 dynamic polygons and
the rest are static polygons in about 100 frames per second.
Abstract: Global Solar Radiation (H) for Dubai and Sharjah,
Latitude 25.25oN, Longitude 55oE and 25.29oN, Longitude 55oE
respectively have been studied using sunshine hour data (n) of the
areas using various methods. These calculated global solar radiation
values are then compared to the measured values presented by
NASA. Furthermore, the extraterrestrial (H0), diffuse (Hd) and beam
radiation (Hb) are also calculated. The diffuse radiation is calculated
using methods proposed by Page and Liu and Jordan (L-J). Diffuse
Radiation from the Page method is higher than the L-J method.
Moreover, the clearness index (KT) signifies a clear sky almost all
year round. Rainy days are hardly a few in a year and limited in the
months December to March. The temperature remains between 25oC
in winter to 44oC in summer and is desirable for thermal applications
of solar energy. From the estimated results, it appears that solar
radiation can be utilized very efficiently throughout the year for
photovoltaic and thermal applications.
Abstract: Environmental awareness and depletion of the
petroleum resources are among vital factors that motivate a number
of researchers to explore the potential of reusing natural fiber as an
alternative composite material in industries such as packaging,
automotive and building constructions. Natural fibers are available in
abundance, low cost, lightweight polymer composite and most
importance its biodegradability features, which often called “ecofriendly"
materials. However, their applications are still limited due
to several factors like moisture absorption, poor wettability and large
scattering in mechanical properties. Among the main challenges on
natural fibers reinforced matrices composite is their inclination to
entangle and form fibers agglomerates during processing due to
fiber-fiber interaction. This tends to prevent better dispersion of the
fibers into the matrix, resulting in poor interfacial adhesion between
the hydrophobic matrix and the hydrophilic reinforced natural fiber.
Therefore, to overcome this challenge, fiber treatment process is one
common alternative that can be use to modify the fiber surface
topology by chemically, physically or mechanically technique.
Nevertheless, this paper attempt to focus on the effect of
mercerization treatment on mechanical properties enhancement of
natural fiber reinforced composite or so-called bio composite. It
specifically discussed on mercerization parameters, and natural fiber
reinforced composite mechanical properties enhancement.
Abstract: In pattern recognition applications the low level
segmentation and the high level object recognition are generally
considered as two separate steps. The paper presents a method that
bridges the gap between the low and the high level object
recognition. It is based on a Bayesian network representation and
network propagation algorithm. At the low level it uses hierarchical
structure of quadratic spline wavelet image bases. The method is
demonstrated for a simple circuit diagram component identification
problem.
Abstract: The successful use of CDMA technology is based on
the construction of large families of encoding sequences with good
correlation properties. This paper discusses PN sequence generation
based on Residue Arithmetic with an effort to improve the performance
of existing interference-limited CDMA technology for mobile
cellular systems. All spreading codes with residual number system
proposed earlier did not consider external interferences, multipath
propagation, Doppler effect etc. In literature the use of residual
arithmetic in DS-CDMA was restricted to encoding of already spread
sequence; where spreading of sequence is done by some existing
techniques. The novelty of this paper is the use of residual number
system in generation of the PN sequences which is used to spread
the message signal. The significance of cross-correlation factor in
alleviating multi-access interference is also discussed. The RNS based
PN sequence has superior performance than most of the existing
codes that are widely used in DS-CDMA applications. Simulation
results suggest that the performance of the proposed system is
superior to many existing systems.
Abstract: The classic problem of recovering arbitrary values of
a band-limited signal from its samples has an added complication
in software radio applications; namely, the resampling calculations
inevitably fold aliases of the analog signal back into the original
bandwidth. The phenomenon is quantified by the spur-free dynamic
range. We demonstrate how a novel application of the Remez (Parks-
McClellan) algorithm permits optimal signal recovery and SFDR, far
surpassing state-of-the-art resamplers.
Abstract: This paper presents the design and implementation of a fully integrated transimpedance amplifier (TIA) as the analog frontend receiver for Capacitive Micromachined Ultrasound Transducers (CMUTs) for ultrasound biomicroscope imaging application. The amplifier is designed to amplify the received signals from 17.5MHz to 52.5MHz with a center frequency of 35MHz. The TIA was fabricated in GF 0.18μm 1P6M 30V high voltage process. The measurement results show that the designed amplifier can reach a transimpedance gain of 61.08dBΩ and operating frequency from 17.5MHz to 100MHz with 1VP-P output voltage under 6V power supply.
Abstract: Context awareness is a capability whereby mobile
computing devices can sense their physical environment and adapt
their behavior accordingly. The term context-awareness, in
ubiquitous computing, was introduced by Schilit in 1994 and has
become one of the most exciting concepts in early 21st-century
computing, fueled by recent developments in pervasive computing
(i.e. mobile and ubiquitous computing). These include computing
devices worn by users, embedded devices, smart appliances, sensors
surrounding users and a variety of wireless networking technologies.
Context-aware applications use context information to adapt
interfaces, tailor the set of application-relevant data, increase the
precision of information retrieval, discover services, make the user
interaction implicit, or build smart environments. For example: A
context aware mobile phone will know that the user is currently in a
meeting room, and reject any unimportant calls. One of the major
challenges in providing users with context-aware services lies in
continuously monitoring their contexts based on numerous sensors
connected to the context aware system through wireless
communication. A number of context aware frameworks based on
sensors have been proposed, but many of them have neglected the
fact that monitoring with sensors imposes heavy workloads on
ubiquitous devices with limited computing power and battery. In this
paper, we present CALEEF, a lightweight and energy efficient
context aware framework for resource limited ubiquitous devices.
Abstract: The knowledge of the nature of loading is very
important in order to hold account on the total behavior such as
vibration, shock, fatigue, etc. Fatigue present 90% of failure when
loadings fatigues are very complex. In this paper a study of double
through crack at hole for plate subjected to fatigue loading is
presented. Various modes loading are studied where the applied load
is the same one. The fatigue life is given where the effect of stress
ratio is highlighted. This work is conducted on aluminum alloy 2024
T351 used for much aerospace and aeronautics applications. The
fatigue crack growth behavior with constant amplitude is studied
using the AFGROW code when Forman model is applied. The
fatigue crack growth rate and fatigue life for different loading modes
are compared with variation of others geometrical parameter such as
thickness and dimensions of notch hole.
Abstract: As chip manufacturing technology is suddenly on the
threshold of major evaluation, which shrinks chip in size and
performance, LFSR (Linear Feedback Shift Register) is implemented
in layout level which develops the low power consumption chip,
using recent CMOS, sub-micrometer layout tools. Thus LFSR
counter can be a new trend setter in cryptography and is also
beneficial as compared to GRAY & BINARY counter and variety of
other applications.
This paper compares 3 architectures in terms of the hardware
implementation, CMOS layout and power consumption, using
Microwind CMOS layout tool. Thus it provides solution to a low
power architecture implementation of LFSR in CMOS VLSI.
Abstract: With the extensive inclusion of document, especially
text, in the business systems, data mining does not cover the full
scope of Business Intelligence. Data mining cannot deliver its impact
on extracting useful details from the large collection of unstructured
and semi-structured written materials based on natural languages.
The most pressing issue is to draw the potential business intelligence
from text. In order to gain competitive advantages for the business, it
is necessary to develop the new powerful tool, text mining, to expand
the scope of business intelligence.
In this paper, we will work out the strong points of text mining in
extracting business intelligence from huge amount of textual
information sources within business systems. We will apply text
mining to each stage of Business Intelligence systems to prove that
text mining is the powerful tool to expand the scope of BI. After
reviewing basic definitions and some related technologies, we will
discuss the relationship and the benefits of these to text mining. Some
examples and applications of text mining will also be given. The
motivation behind is to develop new approach to effective and
efficient textual information analysis. Thus we can expand the scope
of Business Intelligence using the powerful tool, text mining.
Abstract: Deployment of pneumatic muscles in various
industrial applications is still in its early days, considering the relative
newness of these components. The field of robotics holds particular
future potential for pneumatic muscles, especially in view of their
specific behaviour known as compliance. The paper presents and
discusses an innovative constructive solution for a gripper system
mountable on an industrial robot, based on actuation by a linear
pneumatic muscle and transmission of motion by gear and rack
mechanism. The structural, operational and constructive models of
the new gripper are presented, along with some of the experimental
results obtained subsequently to the testing of a prototype. Further
presented are two control variants of the gripper system, one by
means of a 3/2-way fast-switching solenoid valve, the other by means
of a proportional pressure regulator. Advantages and disadvantages
are discussed for both variants.
Abstract: Never has a revolution affected all aspects of
humanity as the communication revolution during the past two
decades. This revolution, with all its advances and utilities, swept the
world thus becoming an integral part of our lives, hence giving way
to emerging applications at the social, economic, political, and
educational levels. More specifically, such applications have changed
the delivery system through which learning is acquired by students.
Interaction with educators, accessibility to content, and creative
delivery options are but a few facets of the new learning experience
now being offered through the use of technology in the educational
field. With different success rates, third world countries have tried to
pace themselves with use of educational technology in advanced
parts of the world. One such country is the small rich-oil state of
Kuwait which has tried to adopt the e-educational model, however,
an evaluation of such trial is yet to be done. This study aimed to fill
the void of research conducted around that topic. The study explored
students' acceptance of incorporating communication technologies in
higher education in Kuwait. Students' responses to survey questions
presented an overview of the e-learning experience in this country,
and drew a framework through which implications and suggestions
for future research were discussed to better serve the advancement of
e-education in developing countries.
Abstract: In this paper we present high performance
dynamically allocated multi-queue (DAMQ) buffer schemes for fault
tolerance systems on chip applications that require an interconnection
network. Two virtual channels shared the same buffer space. Fault
tolerant mechanisms for interconnection networks are becoming a
critical design issue for large massively parallel computers. It is also
important to high performance SoCs as the system complexity keeps
increasing rapidly. On the message switching layer, we make
improvement to boost system performance when there are faults
involved in the components communication. The proposed scheme is
when a node or a physical channel is deemed as faulty, the previous
hop node will terminate the buffer occupancy of messages destined
to the failed link. The buffer usage decisions are made at switching
layer without interactions with higher abstract layer, thus buffer
space will be released to messages destined to other healthy nodes
quickly. Therefore, the buffer space will be efficiently used in case
fault occurs at some nodes.
Abstract: Owing the fact that optimization of business process
is a crucial requirement to navigate, survive and even thrive in
today-s volatile business environment, this paper presents a
framework for selecting a best-fit optimization package for solving
complex business problems. Complexity level of the problem and/or
using incorrect optimization software can lead to biased solutions of
the optimization problem. Accordingly, the proposed framework
identifies a number of relevant factors (e.g. decision variables,
objective functions, and modeling approach) to be considered during
the evaluation and selection process. Application domain, problem
specifications, and available accredited optimization approaches are
also to be regarded. A recommendation of one or two optimization
software is the output of the framework which is believed to provide
the best results of the underlying problem. In addition to a set of
guidelines and recommendations on how managers can conduct an
effective optimization exercise is discussed.
Abstract: In this article, we expose our research work in
Human-machine Interaction. The research consists in manipulating
the workspace by eyes. We present some of our results, in particular
the detection of eyes and the mouse actions recognition. Indeed, the
handicaped user becomes able to interact with the machine in a more
intuitive way in diverse applications and contexts. To test our
application we have chooses to work in real time on videos captured
by a camera placed in front of the user.