Abstract: The concept of flexible manufacturing is highly
appealing in gaining a competitive edge in the market by quickly
adapting to the changing customer needs. Scheduling jobs on flexible
manufacturing systems (FMSs) is a challenging task of managing the
available flexibility on the shop floor to react to the dynamics of the
environment in real-time. In this paper, an agent-oriented scheduling
framework that can be integrated with a real or a simulated FMS is
proposed. This framework works in stochastic environments with a
dynamic model of job arrival. It supports a hierarchical cooperative
scheduling that builds on the available flexibility of the shop floor.
Testing the framework on a model of a real FMS showed the
capability of the proposed approach to overcome the drawbacks of
the conventional approaches and maintain a near optimal solution
despite the dynamics of the operational environment.
Abstract: This paper describes a research project on Year 3 primary school students in Malaysia in their use of computer-based video game to enhance learning of multiplication facts (tables) in the Mathematics subject. This study attempts to investigate whether video games could actually contribute to positive effect on children-s learning or otherwise. In conducting this study, the researchers assume a neutral stand in the investigation as an unbiased outcome of the study would render reliable response to the impact of video games in education which would contribute to the literature of technology-based education as well as impact to the pedagogical aspect of formal education. In order to conduct the study, a subject (Mathematics) with a specific topic area in the subject (multiplication facts) is chosen. The study adopts a causal-comparative research to investigate the impact of the inclusion of a computer-based video game designed to teach multiplication facts to primary level students. Sample size is 100 students divided into two i.e., A: conventional group and B conventional group aided by video games. The conventional group (A) would be taught multiplication facts (timetables) and skills conventionally. The other group (B) underwent the same lessons but with supplementary activity: a computer-based video game on multiplication which is called Timez-Attack. Analysis of marks accrued from pre-test will be compared to post- test using comparisons of means, t tests, and ANOVA tests to investigate the impact of computer games as an added learning activity. The findings revealed that video games as a supplementary activity to classroom learning brings significant and positive effect on students- retention and mastery of multiplication tables as compared to students who rely only upon formal classroom instructions.
Abstract: The fact that traditional food safety system in the
absence of food safety culture is inadequate has recently become a
cause of concern for food safety professionals and other stakeholders.
Focusing on implementation of traditional food safety system i.e
HACCP prerequisite program and HACCP without the presence of
food safety culture in the food industry has led to the processing,
marketing and distribution of contaminated foods. The results of this
are regular out breaks of food borne illnesses and recalls of foods
from retail outlets with serious consequences to the consumers and
manufacturers alike. This article will consider the importance of food
safety culture, the cases of outbreaks and recalls that occurred when
companies did not make food safety culture a priority. Most
importantly, the food safety cultures of some food industries in South
Africa were assessed from responses to questionnaires from food
safety/food industry professionals in Durban South Africa. The
article was concluded by recommending that both food
industry employees and employers alike take food safety culture
seriously.
Abstract: A research project dealing with the phytoremediation
of a soil polluted by some heavy metals is currently running. The
case study is represented by a mining area in Hamedan province in
the central west part of Iran. The potential of phytoextraction and
phytostabilization of plants was evaluated considering the
concentration of heavy metals in the plant tissues and also the
bioconcentration factor (BCF) and the translocation factor (TF). Also
the several established criteria were applied to define
hyperaccumulator plants in the studied area. Results showed that
none of the collected plant species were suitable for phytoextraction
of Cu, Zn, Fe and Mn, but among the plants, Euphorbia macroclada
was the most efficient in phytostabilization of Cu and Fe, while,
Ziziphora clinopodioides, Cousinia sp. and Chenopodium botrys
were the most suitable for phytostabilization of Zn and Chondrila
juncea and Stipa barbata had the potential for phytostabilization of
Mn. Using the most common criterion, Euphorbia macroclada and
Verbascum speciosum were Fe hyperaccumulator plants. Present
study showed that native plant species growing on contaminated sites
may have the potential for phytoremediation.
Abstract: The importance of hints in an intelligent tutoring system is well understood. The problems however related to their delivering are quite a few. In this paper we propose delivering of hints to be based on considering their usefulness. By this we mean that a hint is regarded as useful to a student if the student has succeeded to solve a problem after the hint was suggested to her/him. Methods from the theory of partial orderings are further applied facilitating an automated process of offering individualized advises on how to proceed in order to solve a particular problem.
Abstract: The rapid growth of e-Commerce services is
significantly observed in the past decade. However, the method to
verify the authenticated users still widely depends on numeric
approaches. A new search on other verification methods suitable for
online e-Commerce is an interesting issue. In this paper, a new online
signature-verification method using angular transformation is
presented. Delay shifts existing in online signatures are estimated by
the estimation method relying on angle representation. In the
proposed signature-verification algorithm, all components of input
signature are extracted by considering the discontinuous break points
on the stream of angular values. Then the estimated delay shift is
captured by comparing with the selected reference signature and the
error matching can be computed as a main feature used for verifying
process. The threshold offsets are calculated by two types of error
characteristics of the signature verification problem, False Rejection
Rate (FRR) and False Acceptance Rate (FAR). The level of these two
error rates depends on the decision threshold chosen whose value is
such as to realize the Equal Error Rate (EER; FAR = FRR). The
experimental results show that through the simple programming,
employed on Internet for demonstrating e-Commerce services, the
proposed method can provide 95.39% correct verifications and 7%
better than DP matching based signature-verification method. In
addition, the signature verification with extracting components
provides more reliable results than using a whole decision making.
Abstract: In the present paper, a set of parametric FE stress
analyses is carried out for two-planar welded tubular DKT-joints
under two different axial load cases. Analysis results are used to
present general remarks on the effect of geometrical parameters on
the stress concentration factors (SCFs) at the inner saddle, outer
saddle, toe, and heel positions on the main (outer) brace. Then a new
set of SCF parametric equations is developed through nonlinear
regression analysis for the fatigue design of two-planar DKT-joints.
An assessment study of these equations is conducted against the
experimental data; and the satisfaction of the criteria regarding the
acceptance of parametric equations is checked. Significant effort has
been devoted by researchers to the study of SCFs in various uniplanar
tubular connections. Nevertheless, for multi-planar joints
covering the majority of practical applications, very few
investigations have been reported due to the complexity and high
cost involved.
Abstract: The decisions made by admission control algorithms are
based on the availability of network resources viz. bandwidth, energy,
memory buffers, etc., without degrading the Quality-of-Service (QoS)
requirement of applications that are admitted. In this paper, we
present an energy-aware admission control (EAAC) scheme which
provides admission control for flows in an ad hoc network based
on the knowledge of the present and future residual energy of the
intermediate nodes along the routing path. The aim of EAAC is to
quantify the energy that the new flow will consume so that it can
be decided whether the future residual energy of the nodes along
the routing path can satisfy the energy requirement. In other words,
this energy-aware routing admits a new flow iff any node in the
routing path does not run out of its energy during the transmission
of packets. The future residual energy of a node is predicted using
the Multi-layer Neural Network (MNN) model. Simulation results
shows that the proposed scheme increases the network lifetime. Also
the performance of the MNN model is presented.
Abstract: The linear methods of heart rate variability analysis
such as non-parametric (e.g. fast Fourier transform analysis) and
parametric methods (e.g. autoregressive modeling) has become an
established non-invasive tool for marking the cardiac health, but their
sensitivity and specificity were found to be lower than expected with
positive predictive value
Abstract: The Carrier Frequency Offset (CFO) due to timevarying
fading channel is the main cause of the loss of orthogonality
among OFDM subcarriers which is linked to inter-carrier interference
(ICI). Hence, it is necessary to precisely estimate and compensate the
CFO. Especially for mobile broadband communications, CFO and
channel gain also have to be estimated and tracked to maintain the
system performance. Thus, synchronization pilots are embedded in
every OFDM symbol to track the variations. In this paper, we present
the pilot scheme for both channel and CFO estimation where channel
estimation process can be carried out with only one OFDM symbol.
Additional, the proposed pilot scheme also provides better
performance in CFO estimation comparing with the conventional
orthogonal pilot scheme due to the increasing of signal-tointerference
ratio.
Abstract: This study investigated students- perception of self
efficacy and anxiety in acquiring English language, and consequently
examined the relationship existing among the independent variables,
confounding variables and students- performances in the English
language. The researcher tested the research hypotheses using a
sample group of 318 respondents out of the population size of 400
students. The results obtained revealed that there was a significant
moderate negative relationship between English language anxiety
and performance in English language, but no significant relationship
between self-efficacy and English language performance, among the
middle-school students. There was a significant moderate negative
relationship between English language anxiety and self-efficacy. It
was discovered that general self-efficacy and English language
anxiety represented a significantly more powerful set of predictors
than the set of confounding variables. Thus, the study concluded that
English language anxiety and general self-efficacy were significant
predictors of English language performance among middle-school
students in Satri Si Suriyothai School.
Abstract: Abstraction of water from the dry river sand-beds is
well-known as an alternative source of water during dry seasons.
Internally, because of the form of sand particles, voids are created
which can store water in the riverbeds. Large rivers are rare in South
Africa. Many rivers are sand river types and without water during the
prolonged dry periods. South Africa has not taken full advantage of
water storage in sand as a solution to the growing water scarcity both
in urban and rural areas. The paper reviews the benefits of run-off
storage in sand reservoirs gained from other arid areas and need for
adoption in rural areas of South Africa as an alternative water supply
where it is probable.
Abstract: The error diffusion method generates worm artifacts,
and weakens the edge of the halftone image when the continuous gray
scale image is reproduced by a binary image. First, to enhance the
edges, we propose the edge-enhancing filter by considering the
quantization error information and gradient of the neighboring pixels.
Furthermore, to remove worm artifacts often appearing in a halftone
image, we add adaptively random noise into the weights of an error
filter.
Abstract: Hexapod Machine Tool (HMT) is a parallel robot
mostly based on Stewart platform. Identification of kinematic
parameters of HMT is an important step of calibration procedure. In
this paper an algorithm is presented for identifying the kinematic
parameters of HMT using inverse kinematics error model. Based on
this algorithm, the calibration procedure is simulated. Measurement
configurations with maximum observability are decided as the first
step of this algorithm for a robust calibration. The errors occurring in
various configurations are illustrated graphically. It has been shown
that the boundaries of the workspace should be searched for the
maximum observability of errors. The importance of using
configurations with sufficient observability in calibrating hexapod
machine tools is verified by trial calibration with two different
groups of randomly selected configurations. One group is selected to
have sufficient observability and the other is in disregard of the
observability criterion. Simulation results confirm the validity of the
proposed identification algorithm.
Abstract: Hybrid knowledge model is suggested as an underlying
framework for product development management. It can support such
hybrid features as ontologies and rules. Effective collaboration in
product development environment depends on sharing and reasoning
product information as well as engineering knowledge. Many studies
have considered product information and engineering knowledge.
However, most previous research has focused either on building the
ontology of product information or rule-based systems of engineering
knowledge. This paper shows that F-logic based knowledge model can
support such desirable features in a hybrid way.
Abstract: This paper presents one of the best applications of wireless sensor network for campus Monitoring. With the help of PIR sensor, temperature sensor and humidity sensor, effective utilization of energy resources has been implemented in one of rooms of Sharda University, Greater Noida, India. The RISC microcontroller is used here for analysis of output of sensors and providing proper control using ZigBee protocol. This wireless sensor module presents a tremendous power saving method for any campus
Abstract: Wireless sensor networks (WSN) consists of many sensor nodes that are placed on unattended environments such as military sites in order to collect important information. Implementing a secure protocol that can prevent forwarding forged data and modifying content of aggregated data and has low delay and overhead of communication, computing and storage is very important. This paper presents a new protocol for concealed data aggregation (CDA). In this protocol, the network is divided to virtual cells, nodes within each cell produce a shared key to send and receive of concealed data with each other. Considering to data aggregation in each cell is locally and implementing a secure authentication mechanism, data aggregation delay is very low and producing false data in the network by malicious nodes is not possible. To evaluate the performance of our proposed protocol, we have presented computational models that show the performance and low overhead in our protocol.
Abstract: Diatoms are an important group of aquatic ecosystems and diatom-based indices are increasingly becoming important tools for the assessment of ecological conditions in lotic systems. Although the studies are very limited about Turkish rivers, diatom indices were used for monitoring rivers in different basins. In the present study, we used OMNIDIA program for estimation of stream quality. Some indices have less sensitive (IDP, WAT, LOBO, GENRE, TID, CEE, PT), intermediate sensitivities (IDSE, DESCY, IPS, DI-CH, SLA, IDAP), the others higher sensitivities (SID, IBD, SHE, EPI-D). Among the investigated diatom communities, only a few taxa indicated alfa-mesosaprobity and polysaprobity. Most of the sites were characterized by a great relative contribution of eutraphent and tolerant ones as well as oligosaprobic and betamesosaprobic diatoms. In general, SID and IBD indices gave the best results. This study suggests that the structure of benthic diatom communities and diatom indices, especially SID, can be applied for monitoring rivers in Southern Turkey.
Abstract: In this paper, growth and collapse of a vapour bubble
generated due to a local energy input inside a rigid cylinder and in
the absence of buoyancy forces is investigated using Boundary
Integral Equation Method and Finite Difference Method .The fluid is
treated as potential flow and Boundary Integral Equation Method is
used to solve Laplace-s equation for velocity potential. Different
ratios of the diameter of the rigid cylinder to the maximum radius of
the bubble are considered. Results show that during the collapse
phase of the bubble inside a vertical rigid cylinder, two liquid micro
jets are developed on the top and bottom sides of the vapour bubble
and are directed inward. It is found that by increasing the ratio of the
cylinder diameter to the maximum radius of the bubble, the rate of
the growth and collapse phases of the bubble increases and the life
time of the bubble decreases.
Abstract: Variable ordering heuristics are used in constraint satisfaction algorithms. Different characteristics of various variable ordering heuristics are complementary. Therefore we have tried to get the advantages of all heuristics to improve search algorithms performance for solving constraint satisfaction problems. This paper considers combinations based on products and quotients, and then a newer form of combination based on weighted sums of ratings from a set of base heuristics, some of which result in definite improvements in performance.