Abstract: Non-Destructive evaluation of in-service power
transformer condition is necessary for avoiding catastrophic failures.
Dissolved Gas Analysis (DGA) is one of the important methods.
Traditional, statistical and intelligent DGA approaches have been
adopted for accurate classification of incipient fault sources.
Unfortunately, there are not often enough faulty patterns required for
sufficient training of intelligent systems. By bootstrapping the
shortcoming is expected to be alleviated and algorithms with better
classification success rates to be obtained. In this paper the
performance of an artificial neural network, K-Nearest Neighbour
and support vector machine methods using bootstrapped data are
detailed and shown that while the success rate of the ANN algorithms
improves remarkably, the outcome of the others do not benefit so
much from the provided enlarged data space. For assessment, two
databases are employed: IEC TC10 and a dataset collected from
reported data in papers. High average test success rate well exhibits
the remarkable outcome.
Abstract: This paper focuses on a technique for identifying the geological boundary of the ground strata in front of a tunnel excavation site using the first order adjoint method based on the optimal control theory. The geological boundary is defined as the boundary which is different layers of elastic modulus. At tunnel excavations, it is important to presume the ground situation ahead of the cutting face beforehand. Excavating into weak strata or fault fracture zones may cause extension of the construction work and human suffering. A theory for determining the geological boundary of the ground in a numerical manner is investigated, employing excavating blasts and its vibration waves as the observation references. According to the optimal control theory, the performance function described by the square sum of the residuals between computed and observed velocities is minimized. The boundary layer is determined by minimizing the performance function. The elastic analysis governed by the Navier equation is carried out, assuming the ground as an elastic body with linear viscous damping. To identify the boundary, the gradient of the performance function with respect to the geological boundary can be calculated using the adjoint equation. The weighed gradient method is effectively applied to the minimization algorithm. To solve the governing and adjoint equations, the Galerkin finite element method and the average acceleration method are employed for the spatial and temporal discretizations, respectively. Based on the method presented in this paper, the different boundary of three strata can be identified. For the numerical studies, the Suemune tunnel excavation site is employed. At first, the blasting force is identified in order to perform the accuracy improvement of analysis. We identify the geological boundary after the estimation of blasting force. With this identification procedure, the numerical analysis results which almost correspond with the observation data were provided.
Abstract: The continued growth of the cities is causing an
increase of the amount of surface to illuminate. However, this rise
into lighting brings some unintended consequences such as increased
of energy consumption or the light pollution. To make these effects
less intrusive as possible some councils have chosen to perform a
part-night lighting in some areas. Nonetheless, this kind of shutdown
may cause serious problems which we intend to highlight in this
paper.
Abstract: In this paper, we consider a designed and
implemented phase-cutting dimmer. In fact, the dimmer is closed
loop and a microcontroller calculates and then regulates the firing
delay angles of each channel. Depending on the firing angle, the
harmonic distortion in the input current will not comply with
international standards, such as IEC 61000-3-2 (class C equipments).
For solving this problem, eight harmonic compensators have been
added to the dimmer. So, the proposed dimmer has a little harmonic
distortion in the input current whereas conventional phase-cutting
dimmers are not so. Sensitivity and removed THD of the proposed
dimmer will be presented.
Abstract: It is known that the heart interacts with and adapts to its venous and arterial loading conditions. Various experimental studies and modeling approaches have been developed to investigate the underlying mechanisms. This paper presents a model of the left ventricle derived based on nonlinear stress-length myocardial characteristics integrated over truncated ellipsoidal geometry, and second-order dynamic mechanism for the excitation-contraction coupling system. The results of the model presented here describe the effects of the viscoelastic damping element of the electromechanical coupling system on the hemodynamic response. Different heart rates are considered to study the pacing effects on the performance of the left-ventricle against constant preload and afterload conditions under various damping conditions. The results indicate that the pacing process of the left ventricle has to take into account, among other things, the viscoelastic damping conditions of the myofilament excitation-contraction process. The effects of left ventricular dimensions on the hemdynamic response have been examined. These effects are found to be different at different viscoelastic and pacing conditions.
Abstract: Typically thermal power plants are located near to
surface coal mines that produce huge amount of fly ash as a waste
byproduct. Disposal of fly ash causes significant economic and
environmental problems. Now-a-days, research is going on for bulk
utilization of fly ash. In order to increase its percentage utilization, an
investigation was carried out to evaluate its potential for haul road
construction. This paper presents the laboratory California bearing
ratio (CBR) tests and evaluates the effect of lime on CBR behavior of
fly ash - mine overburden mixes. Tests were performed with different
percentages of lime (2%, 3%, 6%, and 9%). The results show that the
increase in bearing ratio of fly ash-overburden mixes was achieved
by lime treatment. Scanning electron microscopy (SEM) analyses
were conducted on 28 days cured specimens. The SEM study showed
that the bearing ratio development is related to the microstructural
development.
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: Sustainability in rural production system can only be achieved if it can suitably satisfy the local requirement as well as the outside demand with the changing time. With the increased pressure from the food sector in a globalised world, the agrarian economy
needs to re-organise its cultivable land system to be compatible with new management practices as well as the multiple needs of various stakeholders and the changing resource scenario. An attempt has been made to transform this problem into a multi-objective decisionmaking problem considering various objectives, resource constraints and conditional constraints. An interactive fuzzy multi-objective
programming approach has been used for such a purpose taking a
case study in Indian context to demonstrate the validity of the method.
Abstract: In the present article, a new class of solutions of
Einstein field equations is investigated for a spherically symmetric
space-time when the source of gravitation is a perfect fluid. All the
solutions have been derived by making some suitable arrangements
in the field equations. The solutions so obtained have been seen to
describe Schwarzschild interior solutions. Most of the solutions are
subjected to the reality conditions. As far as the authors are aware the
solutions are new.
Abstract: Inner class is a specialized class that defined within a
regular outer class. It is used in some programming languages such as
Java to carry out the task which is related to its outer class. The
functional relatedness between inner class and outer class is always
the main concern of defining an inner class. However, excessive use
of inner class could sabotage the class cohesiveness. In addition,
excessive inner class leads to the difficulty of software maintenance
and comprehension. Our research aims at determining the minimum
threshold for the functional relatedness of inner-outer class. Such
minimum threshold is a guideline for removing or relocating the
excessive inner class. Our research provides a feasible way for
software developers to define inner classes which are functionally
related to the outer class.
Abstract: In a recent year usage of VoIP subscription has increased tremendously as compare to Public Switching Telephone System(PSTN). A VoIP subscriber would like to know the exact tariffs of the calls made using VoIP. As the usage increases, the rate of fraud is also increases, causing users complain about excess billing. This in turn hampers the growth of VoIP .This paper describe the common frauds and attack on VoIP based system and make an attempt to solve the billing attack by creating secured channel between caller and callee.
Abstract: This study analyzed the creativity of student teams
participating in an exploratory information system development
project (ISDP) and examined antecedents of their creativity. By using
partial least squares (PLS) to analyze a sample of thirty-six teams
enrolled in an information system department project training course
that required three semesters of project-based lessons, the results
found social capitals (structural, relational and cognitive social capital)
positively influence knowledge integration. However, relational social
capital does not significantly influence knowledge integration.
Knowledge integration positively affects team creativity. This study
also demonstrated that social capitals significantly influence team
creativity through knowledge integration. The implications of our
findings for future research are discussed.
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: Sensory input plays an important role to human
posture control system to initiate strategy in order to counterpart any
unbalance condition and thus, prevent fall. In previous study, joint
stiffness was observed able to describe certain issues regarding to
movement performance. But, correlation between balance ability and
joint stiffness is still remains unknown. In this study, joint stiffening
strategy at ankle and hip were observed under different sensory
manipulations and its correlation with conventional clinical test
(Functional Reach Test) for balance ability was investigated. In order
to create unstable condition, two different surface perturbations (tilt
up-tilt (TT) down and forward-backward (FB)) at four different
frequencies (0.2, 0.4, 0.6 and 0.8 Hz) were introduced. Furthermore,
four different sensory manipulation conditions (include vision and
vestibular system) were applied to the subject and they were asked to
maintain their position as possible. The results suggested that joint
stiffness were high during difficult balance situation. Less balance
people generated high average joint stiffness compared to balance
people. Besides, adaptation of posture control system under repetitive
external perturbation also suggested less during sensory limited
condition. Overall, analysis of joint stiffening response possible to
predict unbalance situation faced by human
Abstract: The voltage/current characteristics and the effect of
NO2 gas on the electrical conductivity of a PbPc gas sensor array is
investigated. The gas sensor is manufactured using vacuum
deposition of gold electrodes on sapphire substrate with the leadphathalocyanine
vacuum sublimed on the top of the gold electrodes.
Two versions of the PbPc gas sensor array are investigated. The
tested types differ in the gap sizes between the deposited gold
electrodes. The sensors are tested at different temperatures to account
for conductivity changes as the molecular adsorption/desorption rate
is affected by heat. The obtained results found to be encouraging as
the sensors shoed stability and sensitivity towards low concentration
of applied NO2 gas.
Abstract: All the available algorithms for blind estimation namely constant modulus algorithm (CMA), Decision-Directed Algorithm (DDA/DFE) suffer from the problem of convergence to local minima. Also, if the channel drifts considerably, any DDA looses track of the channel. So, their usage is limited in varying channel conditions. The primary limitation in such cases is the requirement of certain overhead bits in the transmit framework which leads to wasteful use of the bandwidth. Also such arrangements fail to use channel state information (CSI) which is an important aid in improving the quality of reception. In this work, the main objective is to reduce the overhead imposed by the pilot symbols, which in effect reduces the system throughput. Also we formulate an arrangement based on certain dynamic Artificial Neural Network (ANN) topologies which not only contributes towards the lowering of the overhead but also facilitates the use of the CSI. A 2×2 Multiple Input Multiple Output (MIMO) system is simulated and the performance variation with different channel estimation schemes are evaluated. A new semi blind approach based on dynamic ANN is proposed for channel tracking in varying channel conditions and the performance is compared with perfectly known CSI and least square (LS) based estimation.
Abstract: The nonlinear damping behavior is usually ignored in
the design of a miniature moving-coil loudspeaker. But when the
loudspeaker operated in air, the damping parameter varies with the
voice-coil displacement corresponding due to viscous air flow. The
present paper presents an identification model as inverse problem to
identify the nonlinear damping parameter in the lumped parameter
model for the loudspeaker. Theoretical results for the nonlinear
damping are verified by using laser displacement measurement
scanner. These results indicate that the damping parameter has the
greatly different nonlinearity between in air and vacuum. It is believed
that the results of the present work can be applied in diagnosis and
sound quality improvement of a miniature loudspeaker.
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: Soil microbial activity is adversely affected by pollutants such as heavy metals, antibiotics and pesticides. Organic amendments including sewage sludge, municipal compost and vermicompost are recently used to improve soil structure and fertility. But, these materials contain heavy metals including Pb, Cd, Zn, Ni and Cu that are toxic to soil microorganisms and may lead to occurrence of more tolerant microbes. Among these, Pb is the most abundant and has more negative effect on soil microbial ecology. In this study, Pb levels of 0, 100, 200, 300, 400 and 500 mg Pb [as Pb(NO3)2] per kg soil were added to the pots containing 2 kg of a loamy soil and incubated for 6 months at 25°C with soil moisture of - 0.3 MPa. Dehydrogenase activity of soil as a measure of microbial activity was determined on 15, 30, 90 and 180 days after incubation. Triphenyl tetrazolium chloride (TTC) was used as an electron acceptor in this assay. PICTs (IC50 values) were calculated for each Pb level and incubation time. Soil microbial activity was decreased by increasing Pb level during 30 days of incubation but the induced tolerance appeared on day 90 and thereafter. During 90 to 180 days of incubation, the PICT was gradually developed by increasing Pb level up to 200 mg kg-1, but the rate of enhancement was steeper at higher concentrations.
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.