Abstract: Developments in scientific and technical area cause to use new methods and techniques in education, as is the case in all fields. Especially, the internet contributes a variety of new methods to design virtual and real time laboratory applications in education. In this study, a real time virtual laboratory is designed and implemented for analog and digital communications laboratory experiments by using Lab VIEW program for Marmara University Electronics-Communication Department. In this application, students can access the virtual laboratory web site and perform their experiments without any limitation of time and location so as the students can observe the signals by changing the parameters of the experiment and evaluate the results.
Abstract: Cross sections of As radionuclides in the interaction of natGe with 14-30 MeV protons have been deduced by off-line y-ray spectroscopy to find optimal reaction channels leading to radiotracers for positron emission tomography. The experimental results were compared with the previous results and those estimated by the compound nucleus reaction model.
Abstract: The computer, among the most important inventions of the twentieth century, has become an increasingly important component in our everyday lives. Computer games also have become increasingly popular among people day-by-day, owing to their features based on realistic virtual environments, audio and visual features, and the roles they offer players. In the present study, the metaphors students have for computer games are investigated, as well as an effort to fill the gap in the literature. Students were asked to complete the sentence—‘Computer game is like/similar to….because….’— to determine the middle school students’ metaphorical images of the concept for ‘computer game’. The metaphors created by the students were grouped in six categories, based on the source of the metaphor. These categories were ordered as ‘computer game as a means of entertainment’, ‘computer game as a beneficial means’, ‘computer game as a basic need’, ‘computer game as a source of evil’, ‘computer game as a means of withdrawal’, and ‘computer game as a source of addiction’, according to the number of metaphors they included.
Abstract: In 2002 an amendment to SOLAS opened for
lightweight material constructions in vessels if the same fire safety as
in steel constructions could be obtained. FISPAT (FIreSPread
Analysis Tool) is a computer application that simulates fire spread
and fault injection in cruise vessels and identifies fire sensitive areas.
It was developed to analyze cruise vessel designs and provides a
method to evaluate network layout and safety of cruise vessels. It
allows fast, reliable and deterministic exhaustive simulations and
presents the result in a graphical vessel model. By performing the
analysis iteratively while altering the cruise vessel design it can be
used along with fire chamber experiments to show that the
lightweight design can be as safe as a steel construction and that
SOLAS regulations are fulfilled.
Abstract: The study was a case study analysis about Thai Asia
Pacific Brewery Company. The purpose was to analyze the
company’s marketing objective, marketing strategy at company level,
and marketing mix before liquor liberalization in 2000. Methods used
in this study were qualitative and descriptive research approach
which demonstrated the following results of the study demonstrated
as follows: (1) Marketing objective was to increase market share of
Heineken and Amtel, (2) the company’s marketing strategies were
brand building strategy and distribution strategy. Additionally, the
company also conducted marketing mix strategy as follows. Product
strategy: The company added more beer brands namely Amstel and
Tiger to provide additional choice to consumers, product and
marketing research, and product development. Price strategy: the
company had taken the following into consideration: cost,
competitor, market, economic situation and tax. Promotion strategy:
the company conducted sales promotion and advertising. Distribution
strategy: the company extended channels its channels of distribution
into food shops, pubs and various entertainment places. This strategy
benefited interested persons and people who were engaged in the beer
business.
Abstract: This paper deals with the development of a Jacobean model for a 4-axes indigenously developed scara robot arm in the laboratory. This model is used to study the relation between the velocities and the forces in the robot while it is doing the pick and place operation.
Abstract: Domineering is a classic two-player combinatorial
game usually played on a rectangular board. Three-player Domineering
is the three-player version of Domineering played on a three
dimensional board. Experimental results are presented for x×y ×z
boards with x + y + z < 10 and x, y, z ≥ 2. Also, some theoretical
results are shown for 2 × 2 × n board with n even and n ≥ 4.
Abstract: This paper presents a method to support dynamic
packing in cases when no collision-free path can be found. The
method, which is primarily based on path planning and shrinking of
geometries, suggests a minimal geometry design change that results
in a collision-free assembly path. A supplementing approach to
optimize geometry design change with respect to redesign cost is
described. Supporting this dynamic packing method, a new method
to shrink geometry based on vertex translation, interweaved with
retriangulation, is suggested. The shrinking method requires neither
tetrahedralization nor calculation of medial axis and it preserves the
topology of the geometry, i.e. holes are neither lost nor introduced.
The proposed methods are successfully applied on industrial
geometries.
Abstract: This research presented in this paper is an on-going
project of an application of neural network and fuzzy models to
evaluate the sociological factors which affect the educational
performance of the students in Sri Lanka. One of its major goals is to
prepare the grounds to device a counseling tool which helps these
students for a better performance at their examinations, especially at
their G.C.E O/L (General Certificate of Education-Ordinary Level)
examination. Closely related sociological factors are collected as raw
data and the noise of these data are filtered through the fuzzy
interface and the supervised neural network is being utilized to
recognize the performance patterns against the chosen social factors.
Abstract: In this paper discrete choice models, Logit and Probit
are examined in order to predict the economic recession or expansion
periods in USA. Additionally we propose an adaptive neuro-fuzzy
inference system with triangular membership function. We examine
the in-sample period 1947-2005 and we test the models in the out-of
sample period 2006-2009. The forecasting results indicate that the
Adaptive Neuro-fuzzy Inference System (ANFIS) model outperforms
significant the Logit and Probit models in the out-of sample period.
This indicates that neuro-fuzzy model provides a better and more
reliable signal on whether or not a financial crisis will take place.
Abstract: A system for market identification (SMI) is presented.
The resulting representations are multivariable dynamic demand
models. The market specifics are analyzed. Appropriate models and
identification techniques are chosen. Multivariate static and dynamic
models are used to represent the market behavior. The steps of the
first stage of SMI, named data preprocessing, are mentioned. Next,
the second stage, which is the model estimation, is considered in more
details. Stepwise linear regression (SWR) is used to determine the
significant cross-effects and the orders of the model polynomials. The
estimates of the model parameters are obtained by a numerically stable
estimator. Real market data is used to analyze SMI performance.
The main conclusion is related to the applicability of multivariate
dynamic models for representation of market systems.
Abstract: The continuity in the electric supply of the electric installations is becoming one of the main requirements of the electric supply network (generation, transmission, and distribution of the electric energy). The achievement of this requirement depends from one side on the structure of the electric network and on the other side on the avaibility of the reserve source provided to maintain the supply in case of failure of the principal one. The avaibility of supply does not only depends on the reliability parameters of the both sources (principal and reserve) but it also depends on the reliability of the circuit breaker which plays the role of interlocking the reserve source in case of failure of the principal one. In addition, the principal source being under operation, its control can be ideal and sure, however, for the reserve source being in stop, a preventive maintenances which proceed on time intervals (periodicity) and for well defined lengths of time are envisaged, so that this source will always available in case of the principal source failure. The choice of the periodicity of preventive maintenance of the source of reserve influences directly the reliability of the electric feeder system In this work and on the basis of the semi- markovian's processes, the influence of the time of interlocking the reserve source upon the reliability of an industrial electric network is studied and is given the optimal time of interlocking the reserve source in case of failure the principal one, also the influence of the periodicity of the preventive maintenance of the source of reserve is studied and is given the optimal periodicity.
Abstract: The utilization of cheese whey as a fermentation
substrate to produce bio-ethanol is an effort to supply bio-ethanol
demand as a renewable energy. Like other process systems, modeling
is also required for fermentation process design, optimization and
plant operation. This research aims to study the fermentation process
of cheese whey by applying mathematics and fundamental concept in
chemical engineering, and to investigate the characteristic of the
cheese whey fermentation process. Steady state simulation results for
inlet substrate concentration of 50, 100 and 150 g/l, and various
values of hydraulic retention time, showed that the ethanol
productivity maximum values were 0.1091, 0.3163 and 0.5639 g/l.h
respectively. Those values were achieved at hydraulic retention time
of 20 hours, which was the minimum value used in this modeling.
This showed that operating reactor at low hydraulic retention time
was favorable. Model of bio-ethanol production from cheese whey
will enhance the understanding of what really happen in the
fermentation process.
Abstract: This paper proposes an effective algorithm approach to hybrid control systems combining fuzzy logic and conventional control techniques of controlling the speed of induction motor assumed to operate in high-performance drives environment. The introducing of fuzzy logic in the control systems helps to achieve good dynamical response, disturbance rejection and low sensibility to parameter variations and external influences. Some fundamentals of the fuzzy logic control are preliminary illustrated. The developed control algorithm is robust, efficient and simple. It also assures precise trajectory tracking with the prescribed dynamics. Experimental results have shown excellent tracking performance of the proposed control system, and have convincingly demonstrated the validity and the usefulness of the hybrid fuzzy controller in high-performance drives with parameter and load uncertainties. Satisfactory performance was observed for most reference tracks.
Abstract: Discrete choice model is the most used methodology for studying traveler-s mode choice and demand. However, to calibrate the discrete choice model needs to have plenty of questionnaire survey. In this study, an aggregative model is proposed. The historical data of passenger volumes for high speed rail and domestic civil aviation are employed to calibrate and validate the model. In this study, different models are compared so as to propose the best one. From the results, systematic equations forecast better than single equation do. Models with the external variable, which is oil price, are better than models based on closed system assumption.
Abstract: Glomerular filtration rate (GFR) is a measure of
kidney function. It is usually estimated from serum concentrations of
cystatin C or creatinine although there has been considerable debate
in the literature about (i) the best equation to use and (ii) the
variability in the correlation between the concentrations of creatinine
and cystatin C. The equations for GFR can be written in a general
form and from these I calculate the error of the GFR estimates
associated with analyte measurement error. These show that the
error of the GFR estimates is such that it is not possible to distinguish
between the equations over much of the concentration range of either
analyte. The general forms of the equations are also used to derive
an expression for the concentration of cystatin C as a function of the
concentration of creatinine. This equation shows that these analyte
concentrations are not linearly related. Clinical reports of cystatin C
and creatinine concentration are consistent with the expression
derived.
Abstract: In this paper delamination phenomenon in
Carbon-Epoxy laminated composite material is investigated
numerically. Arcan apparatus and specimen is modeled in ABAQUS
finite element software for different loading conditions and crack
geometries. The influence of variation of crack geometry on
interlaminar fracture stress intensity factor and energy release rate for
various mixed mode ratios and pure mode I and II was studied. Also,
correction factors for this specimen for different crack length ratios
were calculated. The finite element results indicate that for loading
angles close to pure mode-II loading, a high ratio of mode-II to
mode-I fracture is dominant and there is an opposite trend for loading
angles close to pure mode-I loading. It confirms that by varying the
loading angle of Arcan specimen pure mode-I, pure mode-II and a
wide range of mixed-mode loading conditions can be created and
tested. Also, numerical results confirm that the increase of the mode-
II loading contribution leads to an increase of fracture resistance in
the CF/PEI composite (i.e., a reduction in the total strain energy
release rate) and the increase of the crack length leads to a reduction
of interlaminar fracture resistance in the CF/PEI composite (i.e., an
increase in the total interlaminar strain energy release rate).
Abstract: This paper proposes a hybrid method for eyes localization
in facial images. The novelty is in combining techniques
that utilise colour, edge and illumination cues to improve accuracy.
The method is based on the observation that eye regions have dark
colour, high density of edges and low illumination as compared
to other parts of face. The first step in the method is to extract
connected regions from facial images using colour, edge density and
illumination cues separately. Some of the regions are then removed
by applying rules that are based on the general geometry and shape
of eyes. The remaining connected regions obtained through these
three cues are then combined in a systematic way to enhance the
identification of the candidate regions for the eyes. The geometry
and shape based rules are then applied again to further remove the
false eye regions. The proposed method was tested using images from
the PICS facial images database. The proposed method has 93.7%
and 87% accuracies for initial blobs extraction and final eye detection
respectively.
Abstract: The paper gives the pilot results of the project that is
oriented on the use of data mining techniques and knowledge
discoveries from production systems through them. They have been
used in the management of these systems. The simulation models of
manufacturing systems have been developed to obtain the necessary
data about production. The authors have developed the way of
storing data obtained from the simulation models in the data
warehouse. Data mining model has been created by using specific
methods and selected techniques for defined problems of production
system management. The new knowledge has been applied to
production management system. Gained knowledge has been tested
on simulation models of the production system. An important benefit
of the project has been proposal of the new methodology. This
methodology is focused on data mining from the databases that store
operational data about the production process.
Abstract: A mammography image is composed of low contrast area where the breast tissues and the breast abnormalities such as microcalcification can hardly be differentiated by the medical practitioner. This paper presents the application of active contour models (Snakes) for the segmentation of microcalcification in mammography images. Comparison on the microcalcifiation areas segmented by the Balloon Snake, Gradient Vector Flow (GVF) Snake, and Distance Snake is done against the true value of the microcalcification area. The true area value is the average microcalcification area in the original mammography image traced by the expert radiologists. From fifty images tested, the result obtained shows that the accuracy of the Balloon Snake, GVF Snake, and Distance Snake in segmenting boundaries of microcalcification are 96.01%, 95.74%, and 95.70% accuracy respectively. This implies that the Balloon Snake is a better segmentation method to locate the exact boundary of a microcalcification region.