Abstract: In this paper we propose a new criterion for solving
the problem of channel shortening in multi-carrier systems. In a
discrete multitone receiver, a time-domain equalizer (TEQ) reduces
intersymbol interference (ISI) by shortening the effective duration of
the channel impulse response. Minimum mean square error (MMSE)
method for TEQ does not give satisfactory results. In [1] a new
criterion for partially equalizing severe ISI channels to reduce the
cyclic prefix overhead of the discrete multitone transceiver (DMT),
assuming a fixed transmission bandwidth, is introduced. Due to
specific constrained (unit morm constraint on the target impulse
response (TIR)) in their method, the freedom to choose optimum
vector (TIR) is reduced. Better results can be obtained by avoiding
the unit norm constraint on the target impulse response (TIR). In
this paper we change the cost function proposed in [1] to the cost
function of determining the maximum of a determinant subject to
linear matrix inequality (LMI) and quadratic constraint and solve the
resulting optimization problem. Usefulness of the proposed method
is shown with the help of simulations.
Abstract: Extracting and elaborating software requirements and
transforming them into viable software architecture are still an
intricate task. This paper defines a solution architecture which is
based on the blurred amalgamation of problem space and solution
space. The dependencies between domain constraints, requirements
and architecture and their importance are described that are to be
considered collectively while evolving from problem space to
solution space. This paper proposes a revised version of Twin Peaks
Model named Win Peaks Model that reconciles software
requirements and architecture in more consistent and adaptable
manner. Further the conflict between stakeholders- win-requirements
is resolved by proposed Voting methodology that is simple
adaptation of win-win requirements negotiation model and QARCC.
Abstract: Vehicle which are turning or maneuvering at high speeds
are susceptible to sliding and subsequently deviate from desired path. In
this paper the dynamics governing the Yaw/Roll behavior of a vehicle
has been simulated. Two different simulations have been used one for
the real vehicle, for which a fuzzy controller is designed to increase its
directional stability property. The other simulation is for a hypothetical
vehicle with much higher tire cornering stiffness which is capable of
developing the required lateral forces at the tire-ground patch contact to
attain the desired lateral acceleration for the vehicle to follow the
desired path without slippage. This simulation model is our reference
model.
The logic for keeping the vehicle on the desired track in the cornering
or maneuvering state is to have some braking forces on the inner or
outer tires based on the direction of vehicle deviation from the desired
path. The inputs to our vehicle simulation model is steer angle δ and
vehicle velocity V , and the outputs can be any kinematical parameters
like yaw rate, yaw acceleration, side slip angle, rate of side slip angle
and so on. The proposed fuzzy controller is a feed forward controller.
This controller has two inputs which are steer angle δ and vehicle
velocity V, and the output of the controller is the correcting moment M,
which guides the vehicle back to the desired track. To develop the
membership functions for the controller inputs and output and the fuzzy
rules, the vehicle simulation has been run for 1000 times and the
correcting moment have been determined by trial and error. Results of
the vehicle simulation with fuzzy controller are very promising
and show the vehicle performance is enhanced greatly over the
vehicle without the controller. In fact the vehicle performance
with the controller is very near the performance of the reference
ideal model.
Abstract: In areas of low to moderate seismicity many building contents and equipment are not positively fixed to the floor or tied to adjacent walls. Under seismic induced horizontal vibration, such contents and equipment can suffer from damage by either overturning or impact associated with rocking. This paper focuses on the estimation of shock on typical contents and equipment due to rocking. A simplified analytical model is outlined that can be used to estimate the maximum acceleration on a rocking object given its basic geometric and mechanical properties. The developed model was validated against experimental results. The experimental results revealed that the maximum shock acceleration can be underestimated if the static stiffness of the materials at the interface between the rocking object and floor is used rather than the dynamic stiffness. Excellent agreement between the model and experimental results was found when the dynamic stiffness for the interface material was used, which was found to be generally much higher than corresponding static stiffness under different investigated boundary conditions of the cushion. The proposed model can be a beneficial tool in performing a rapid assessment of shock sensitive components considered for possible seismic rectification.
Abstract: This paper provides the design steps of a robust Linear
Matrix Inequality (LMI) based iterative multivariable PID controller
whose duty is to drive a sample power system that comprises a
synchronous generator connected to a large network via a step-up
transformer and a transmission line. The generator is equipped with
two control-loops, namely, the speed/power (governor) and voltage
(exciter). Both loops are lumped in one where the error in the
terminal voltage and output active power represent the controller
inputs and the generator-exciter voltage and governor-valve position
represent its outputs. Multivariable PID is considered here because of
its wide use in the industry, simple structure and easy
implementation. It is also preferred in plants of higher order that
cannot be reduced to lower ones. To improve its robustness to
variation in the controlled variables, H∞-norm of the system transfer
function is used. To show the effectiveness of the controller, divers
tests, namely, step/tracking in the controlled variables, and variation
in plant parameters, are applied. A comparative study between the
proposed controller and a robust H∞ LMI-based output feedback is
given by its robustness to disturbance rejection. From the simulation
results, the iterative multivariable PID shows superiority.
Abstract: Losses reduction initiatives in distribution systems
have been activated due to the increasing cost of supplying
electricity, the shortage in fuel with ever-increasing cost to produce
more power, and the global warming concerns. These initiatives have
been introduced to the utilities in shape of incentives and penalties.
Recently, the electricity distribution companies in Oman have been
incentivized to reduce the distribution technical and non-technical
losses with an equal annual reduction rate for 6 years. In this paper,
different techniques for losses reduction in Mazoon Electricity
Company (MZEC) are addressed. In this company, high numbers of
substation and feeders were found to be non-compliant with the
Distribution System Security Standard (DSSS). Therefore, 33
projects have been suggested to bring non-complying 29 substations
and 28 feeders to meet the planed criteria and to comply with the
DSSS. The largest part of MZEC-s network (South Batinah region)
was modeled by ETAP software package. The model has been
extended to implement the proposed projects and to examine their
effects on losses reduction. Simulation results have shown that the
implementation of these projects leads to a significant improvement
in voltage profile, and reduction in the active and the reactive power
losses. Finally, the economical analysis has revealed that the
implementation of the proposed projects in MZEC leads to an annual
saving of about US$ 5 million.
Abstract: The effect of wood vinegar, entomopathogenic
nematodes ((Steinernema thailandensis n. sp.) and fermented organic
substances from four plants such as: Derris elliptica Roxb, Stemona
tuberosa Lour, Tinospora crispa Mier and Azadirachta indica J. were
tested on the five varieties of sweetpotato with potential for
bioethanol production ie. Taiwan, China, PROC No.65-16, Phichit
166-5, and Phichit 129-6. The experimental plots were located at
Faculty of Agriculture, Natural Resources and Environment,
Naresuan University, Phitsanulok, Thailand. The aim of this study
was to compare the efficiency of the five treatments for growth, yield
and insect infestation on the five varieties of sweetpotato. Treatment
with entomopathogenic nematodes gave the highest average weight
of sweetpotato tubers (1.3 kg/tuber), followed by wood vinegar,
fermented organic substances and mixed treatment with yields of
0.88, 0.46 and 0.43 kg/tuber, respectively. Also the
entomopathogenic nematode treatment gave significantly higher
average width and length of sweet potato (9.82 cm and 9.45 cm,
respectively). Additionally, the entomopathogenic nematode
provided the best control of insect infestation on sweetpotato leaves
and tubers. Comparison among the varieties of sweetpotato, PROC
NO.65-16 showed the highest weight and length. However, Phichit
129-6 gave significantly higher weight of 0.94 kg/tuber. Lastly, the
lowest sweet potato weevil infestation on leaves and tubers occurred
on Taiwan and Phichit 129-6.
Abstract: The goal of this research is discovering the
determinants of the success or failure of external cooperation in small
and medium enterprises (SMEs). For this, a survey was given to 190
SMEs that experienced external cooperation within the last 3 years. A
logistic regression model was used to derive organizational or strategic
characteristics that significantly influence whether external
collaboration of domestic SMEs is successful or not. Results suggest
that research and development (R&D) features in general
characteristics (both idea creation and discovering market
opportunities) that focused on and emphasized indirected-market
stakeholders (such as complementary companies and affiliates) and
strategies in innovative strategic characteristics raise the probability of
successful external cooperation. This can be used meaningfully to
build a policy or strategy for inducing successful external cooperation
or to understand the innovation of SMEs.
Abstract: Intelligent deep-drawing is an instrumental research field in sheet metal forming. A set of 28 different experimental data have been employed in this paper, investigating the roles of die radius, punch radius, friction coefficients and drawing ratios for axisymmetric workpieces deep drawing. This paper focuses an evolutionary neural network, specifically, error back propagation in collaboration with genetic algorithm. The neural network encompasses a number of different functional nodes defined through the established principles. The input parameters, i.e., punch radii, die radii, friction coefficients and drawing ratios are set to the network; thereafter, the material outputs at two critical points are accurately calculated. The output of the network is used to establish the best parameters leading to the most uniform thickness in the product via the genetic algorithm. This research achieved satisfactory results based on demonstration of neural networks.
Abstract: From a set of shifted, blurred, and decimated image , super-resolution image reconstruction can get a high-resolution image. So it has become an active research branch in the field of image restoration. In general, super-resolution image restoration is an ill-posed problem. Prior knowledge about the image can be combined to make the problem well-posed, which contributes to some regularization methods. In the regularization methods at present, however, regularization parameter was selected by experience in some cases and other techniques have too heavy computation cost for computing the parameter. In this paper, we construct a new super-resolution algorithm by transforming the solving of the System stem Є=An into the solving of the equations X+A*X-1A=I , and propose an inverse iterative method.
Abstract: An aqueous methanol sensor for use in direct
methanol fuel cells (DMFCs) applications is demonstrated; the
methanol sensor is built using dispersed single-walled carbon
nanotubes (SWCNTs) with Nafion117 solution to detect the methanol
concentration in water. The study is aimed at the potential use of the
carbon nanotubes array as a methanol sensor for direct methanol fuel
cells (DMFCs). The concentration of methanol in the fuel circulation
loop of a DMFC system is an important operating parameter, because
it determines the electrical performance and efficiency of the fuel cell
system. The sensor is also operative even at ambient temperatures
and responds quickly to changes in the concentration levels of the
methanol. Such a sensor can be easily incorporated into the methanol
fuel solution flow loop in the DMFC system.
Abstract: Currently, the Malaysian construction industry is
focusing on transforming construction processes from conventional
building methods to the Industrialized Building System (IBS). Still,
research on the decision making of IBS technology adoption with the
influence of contextual factors is scarce. The purpose of this paper is
to explore how contextual factors influence the IBS decision making
in building projects which is perceived by those involved in
construction industry namely construction stakeholders and IBS
supply chain members. Theoretical background, theoretical
frameworks and literatures which identify possible contextual factors
that influence decision making towards IBS technology adoption are
presented. This paper also discusses the importance of contextual
factors in IBS decision making, highlighting some possible crossover
benefits and making some suggestions as to how these can be
utilized. Conclusions are drawn and recommendations are made with
respect to the perception of socio-economic, IBS policy and IBS
technology associated with building projects.
Abstract: Water hyacinth has been used in aquatic systems for
wastewater purification in many years worldwide. The role of water
hyacinth (Eichhornia crassipes) species in polishing nitrate and
phosphorus concentration from municipal wastewater treatment plant
effluent by phytoremediation method was evaluated. The objective
of this project is to determine the removal efficiency of water
hyacinth in polishing nitrate and phosphorus, as well as chemical
oxygen demand (COD) and ammonia. Water hyacinth is considered
as the most efficient aquatic plant used in removing vast range of
pollutants such as organic matters, nutrients and heavy metals. Water
hyacinth, also referred as macrophytes, were cultivated in the
treatment house in a reactor tank of approximately 90(L) x 40(W) x
25(H) in dimension and built with three compartments. Three water
hyacinths were placed in each compartments and water sample in
each compartment were collected in every two days. The plant
observation was conducted by weight measurement, plant uptake and
new young shoot development. Water hyacinth effectively removed
approximately 49% of COD, 81% of ammonia, 67% of phosphorus
and 92% of nitrate. It also showed significant growth rate at starting
from day 6 with 0.33 shoot/day and they kept developing up to 0.38
shoot/day at the end of day 24. From the studies conducted, it was
proved that water hyacinth is capable of polishing the effluent of
municipal wastewater which contains undesirable amount of nitrate
and phosphorus concentration.
Abstract: In this paper we discuss the effect of unbounded particle interaction operator on particle growth and we study how this can address the choice of appropriate time steps of the numerical simulation. We provide also rigorous mathematical proofs showing that large particles become dominating with increasing time while small particles contribute negligibly. Second, we discuss the efficiency of the algorithm by performing numerical simulations tests and by comparing the simulated solutions with some known analytic solutions to the Smoluchowski equation.
Abstract: Quality of Service (QoS) Routing aims to find path between source and destination satisfying the QoS requirements which efficiently using the network resources and underlying routing algorithm and to fmd low-cost paths that satisfy given QoS constraints. One of the key issues in providing end-to-end QoS guarantees in packet networks is determining feasible path that satisfies a number of QoS constraints. We present a Optimized Multi- Constrained Routing (OMCR) algorithm for the computation of constrained paths for QoS routing in computer networks. OMCR applies distance vector to construct a shortest path for each destination with reference to a given optimization metric, from which a set of feasible paths are derived at each node. OMCR is able to fmd feasible paths as well as optimize the utilization of network resources. OMCR operates with the hop-by-hop, connectionless routing model in IP Internet and does not create any loops while fmding the feasible paths. Nodes running OMCR not necessarily maintaining global view of network state such as topology, resource information and routing updates are sent only to neighboring nodes whereas its counterpart link-state routing method depend on complete network state for constrained path computation and that incurs excessive communication overhead.
Abstract: Ontology is widely being used as a tool for organizing
information, creating the relation between the subjects within the
defined knowledge domain area. Various fields such as Civil,
Biology, and Management have successful integrated ontology in
decision support systems for managing domain knowledge and to
assist their decision makers. Gross pollutant traps (GPT) are devices
used in trapping and preventing large items or hazardous particles in
polluting and entering our waterways. However choosing and
determining GPT is a challenge in Malaysia as there are inadequate
GPT data repositories being captured and shared. Hence ontology is
needed to capture, organize and represent this knowledge into
meaningful information which can be contributed to the efficiency of
GPT selection in Malaysia urbanization. A GPT Ontology framework
is therefore built as the first step to capture GPT knowledge which
will then be integrated into the decision support system. This paper
will provide several examples of the GPT ontology, and explain how
it is constructed by using the Protégé tool.
Abstract: This work presents the results of a study carried out to
determine the sliding wear behavior and its effect on the process
parameters of components manufactured by direct metal laser
sintering (DMLS). A standard procedure and specimen had been used
in the present study to find the wear behavior. Using Taguchi-s
experimental technique, an orthogonal array of modified L8 had been
developed. Sliding wear testing using pin-on-disk machine was
carried out and analysis of variance (ANOVA) technique was used to
investigate the effect of process parameters and to identify the main
process parameter that influences the properties of wear behavior on
the DMLS components. It has been found that part orientation, one
of the selected process parameter had more influence on wear as
compared to other selected process parameters.
Abstract: Soccer simulation is an effort to motivate researchers and practitioners to do artificial and robotic intelligence research; and at the same time put into practice and test the results. Many researchers and practitioners throughout the world are continuously working to polish their ideas and improve their implemented systems. At the same time, new groups are forming and they bring bright new thoughts to the field. The research includes designing and executing robotic soccer simulation algorithms. In our research, a soccer simulation player is considered to be an intelligent agent that is capable of receiving information from the environment, analyze it and to choose the best action from a set of possible ones, for its next move. We concentrate on developing a two-phase method for the soccer player agent to choose its best next move. The method is then implemented into our software system called Nexus simulation team of Ferdowsi University. This system is based on TsinghuAeolus[1] team that was the champion of the world RoboCup soccer simulation contest in 2001 and 2002.
Abstract: Business process management (BPM) has become
widely accepted within business community as a means for
improving business performance. However, it is of the highest
importance to incorporate BPM as part of the curriculum at the
university level education in order to achieve the appropriate
acceptance of the method. Goal of the paper is to determine the
current state of education in business process management (BPM) at
the Croatian universities and abroad. It investigates the applied forms
of instruction and teaching methods and gives several proposals for
BPM courses improvement. Since majority of undergraduate and
postgraduate students have limited understanding of business
processes and lack of any practical experience, there is a need for
introducing new teaching approaches. Therefore, we offer some
suggestions for further improvement, among which the introduction
of simulation games environment in BPM education is strongly
recommended.
Abstract: Knowing consumers' preferences and perceptions of
the sensory evaluation of drink products are very significant to
manufacturers and retailers alike. With no appropriate sensory
analysis, there is a high risk of market disappointment. This paper
aims to rank the selected coffee products and also to determine the
best of quality attribute through sensory evaluation using fuzzy
decision making model. Three products of coffee drinks were used
for sensory evaluation. Data were collected from thirty judges at a
hypermarket in Kuala Terengganu, Malaysia. The judges were asked
to specify their sensory evaluation in linguistic terms of the quality
attributes of colour, smell, taste and mouth feel for each product and
also the weight of each quality attribute. Five fuzzy linguistic terms
represent the quality attributes were introduced prior analysing. The
judgment membership function and the weights were compared to
rank the products and also to determine the best quality attribute. The
product of Indoc was judged as the first in ranking and 'taste' as the
best quality attribute. These implicate the importance of sensory
evaluation in identifying consumers- preferences and also the
competency of fuzzy approach in decision making.