Abstract: The segmentation of mouth and lips is a fundamental
problem in facial image analyisis. In this paper we propose a method
for lip segmentation based on rg-color histogram. Statistical analysis
shows, using the rg-color-space is optimal for this purpose of a pure
color based segmentation. Initially a rough adaptive threshold selects
a histogram region, that assures that all pixels in that region are
skin pixels. Based on that pixels we build a gaussian model which
represents the skin pixels distribution and is utilized to obtain a
refined, optimal threshold. We are not incorporating shape or edge
information. In experiments we show the performance of our lip pixel
segmentation method compared to the ground truth of our dataset and
a conventional watershed algorithm.
Abstract: The objective from this paper is to design a solar
thermal engine for space vehicles orbital control and electricity
generation. A computational model is developed for the prediction of
the solar thermal engine performance for different design parameters and conditions in order to enhance the engine efficiency. The engine is divided into two main subsystems. First, the concentrator dish
which receives solar energy from the sun and reflects them to the
cavity receiver. The second one is the cavity receiver which receives
the heat flux reflected from the concentrator and transfers heat to the
fluid passing over. Other subsystems depend on the application required from the engine. For thrust application, a nozzle is
introduced to the system for the fluid to expand and produce thrust.
Hydrogen is preferred as a working fluid in the thruster application.
Results model developed is used to determine the thrust for a
concentrator dish 4 meters in diameter (provides 10 kW of energy),
focusing solar energy to a 10 cm aperture diameter cavity receiver.
The cavity receiver outer length is 50 cm and the internal cavity is 47
cm in length. The suggested design material of the internal cavity is
tungsten to withstand high temperature. The thermal model and
analysis shows that the hydrogen temperature at the plenum reaches
2000oK after about 250 seconds for hot start operation for a flow rate
of 0.1 g/sec.Using solar thermal engine as an electricity generation
device on earth is also discussed. In this case a compressor and
turbine are used to convert the heat gained by the working fluid (air)
into mechanical power. This mechanical power can be converted into
electrical power by using a generator.
Abstract: In this work, the primary compressive strength
components of human femur trabecular bone are qualitatively
assessed using image processing and wavelet analysis. The Primary
Compressive (PC) component in planar radiographic femur trabecular
images (N=50) is delineated by semi-automatic image processing
procedure. Auto threshold binarization algorithm is employed to
recognize the presence of mineralization in the digitized images. The
qualitative parameters such as apparent mineralization and total area
associated with the PC region are derived for normal and abnormal
images.The two-dimensional discrete wavelet transforms are utilized
to obtain appropriate features that quantify texture changes in medical
images .The normal and abnormal samples of the human femur are
comprehensively analyzed using Harr wavelet.The six statistical
parameters such as mean, median, mode, standard deviation, mean
absolute deviation and median absolute deviation are derived at level
4 decomposition for both approximation and horizontal wavelet
coefficients. The correlation coefficient of various wavelet derived
parameters with normal and abnormal for both approximated and
horizontal coefficients are estimated. It is seen that in almost all cases
the abnormal show higher degree of correlation than normals. Further
the parameters derived from approximation coefficient show more
correlation than those derived from the horizontal coefficients. The
parameters mean and median computed at the output of level 4 Harr
wavelet channel was found to be a useful predictor to delineate the
normal and the abnormal groups.
Abstract: The clinical usefulness of heart rate variability is
limited to the range of Holter monitoring software available. These
software algorithms require a normal sinus rhythm to accurately
acquire heart rate variability (HRV) measures in the frequency
domain. Premature ventricular contractions (PVC) or more
commonly referred to as ectopic beats, frequent in heart failure,
hinder this analysis and introduce ambiguity. This investigation
demonstrates an algorithm to automatically detect ectopic beats by
analyzing discrete wavelet transform coefficients. Two techniques
for filtering and replacing the ectopic beats from the RR signal are
compared. One technique applies wavelet hard thresholding
techniques and another applies linear interpolation to replace ectopic
cycles. The results demonstrate through simulation, and signals
acquired from a 24hr ambulatory recorder, that these techniques can
accurately detect PVC-s and remove the noise and leakage effects
produced by ectopic cycles retaining smooth spectra with the
minimum of error.
Abstract: The study investigated the effects of Teaching Games
for Understanding approach on students ‘cognitive learning outcome.
The study was a quasi-experimental non-equivalent pretest-posttest
control group design whereby 10 year old primary school students
(n=72) were randomly assigned to an experimental and a control
group. The experimental group students were exposed with TGfU
approach and the control group with the Traditional Skill approach of
handball game. Game Performance Assessment Instrument (GPAI)
was used to measure students' tactical understanding and decision
making in 3 versus 3 handball game situations. Analysis of
covariance (ANCOVA) was used to analyze the data. The results
reveal that there was a significant difference between the TGfU
approach group and the traditional skill approach group students on
post test score (F (1, 69) = 248.83, p < .05). The findings of this
study suggested the importance of TGfU approach to improve
primary students’ tactical understanding and decision making in
handball game.
Abstract: The aim of this study is to find out and analyze the
role of gender and age on the perceptions of students to the distant
online program offered by Vocational High School in Sakarya
University. The research is based on a questionnaire as a mean of
data collection method to find out the role of age and gender on the
student-s perceptions toward online education, and the study
progressed through finding relationships between the variables used
in the data collection instrument. The findings of the analysis
revealed that although the students registered to the online program
by will, they preferred the traditional face-to-face education due to
the difficulty of the nonverbal communication, their incompetence of
using the technology required, and their belief in traditional face-toface
learning more than online education.
Regarding gender, the results showed that the female students
have a better perception of the online education as opposed to the
male students. Regarding age, the results showed that the older the
students are the more is their preference towards attending face-toface
classes.
Abstract: A new OTA-based logarithmic-control variable gain
current amplifier (LCCA) is presented. It consists of two Operational
Transconductance Amplifier (OTA) and two PMOS transistors
biased in weak inversion region. The circuit operates from 0.6V DC
power supply and consumes 0.6 μW. The linear-dB controllable
output range is 43 dB with maximum error less than 0.5dB. The
functionality of the proposed design was confirmed using HSPICE in
0.35μm CMOS process technology.
Abstract: The 2008 Candlelight Protests of Korea was very
significant to portray the political environment among the South
Korean youth. Many challenges and new advanced technologies have
driven the youth community to be engaged in the political arena that
has shifted them from traditional Korean youth to a very greater
community. Due to historical perspective with the people of North
Korea, the young generation has embraced different view of ethnic
nationalism. This study examines the youth involvement in politics in
line with their level of acceptance the practice of democracy. The
increase usage of new media has shown great results in the survey
results whereby the youth used as a platform to gain political
information and brought higher degree of their sociopolitical interests
among them. Furthermore, the rise of nationalism and patriotism will
be discussed in this paper to the dynamism of the political approaches
used by the Korea government
Abstract: Breast skin-line estimation and breast segmentation is an important pre-process in mammogram image processing and computer-aided diagnosis of breast cancer. Limiting the area to be processed into a specific target region in an image would increase the accuracy and efficiency of processing algorithms. In this paper we are presenting a new algorithm for estimating skin-line and breast segmentation using fast marching algorithm. Fast marching is a partial-differential equation based numerical technique to track evolution of interfaces. We have introduced some modifications to the traditional fast marching method, specifically to improve the accuracy of skin-line estimation and breast tissue segmentation. Proposed modifications ensure that the evolving front stops near the desired boundary. We have evaluated the performance of the algorithm by using 100 mammogram images taken from mini-MIAS database. The results obtained from the experimental evaluation indicate that this algorithm explains 98.6% of the ground truth breast region and accuracy of the segmentation is 99.1%. Also this algorithm is capable of partially-extracting nipple when it is available in the profile.
Abstract: In blended learning environments, the Internet can be combined with other technologies. The aim of this research was to design, introduce and validate a model to support synchronous and asynchronous activities by managing content domains in an Adaptive Hypermedia System (AHS). The application is based on information recovery techniques, clustering algorithms and adaptation rules to adjust the user's model to contents and objects of study. This system was applied to blended learning in higher education. The research strategy used was the case study method. Empirical studies were carried out on courses at two universities to validate the model. The results of this research show that the model had a positive effect on the learning process. The students indicated that the synchronous and asynchronous scenario is a good option, as it involves a combination of work with the lecturer and the AHS. In addition, they gave positive ratings to the system and stated that the contents were adapted to each user profile.
Abstract: Knowledge bases are basic components of expert
systems or intelligent computational programs. Knowledge bases
provide knowledge, events that serve deduction activity,
computation and control. Therefore, researching and developing of
models for knowledge representation play an important role in
computer science, especially in Artificial Intelligence Science and
intelligent educational software. In this paper, the extensive
deduction computational model is proposed to design knowledge
bases whose attributes are able to be real values or functional values.
The system can also solve problems based on knowledge bases.
Moreover, the models and algorithms are applied to produce the
educational software for solving alternating current problems or
solving set of equations automatically.
Abstract: In the present work, study of the vibration of thin cylindrical shells made of a functionally gradient material (FGM) composed of stainless steel and nickel is presented. Material properties are graded in the thickness direction of the shell according to volume fraction power law distribution. The objective is to study the natural frequencies, the influence of constituent volume fractions and the effects of boundary conditions on the natural frequencies of the FG cylindrical shell. The study is carried out using third order shear deformation shell theory. The analysis is carried out using Hamilton's principle. The governing equations of motion of FG cylindrical shells are derived based on shear deformation theory. Results are presented on the frequency characteristics, influence of constituent volume fractions and the effects of clamped-free boundary conditions
Abstract: This paper reports on an effort to address the issue of
inequality in girls- and women-s access to science, engineering and
technology (SET) education and careers through raising awareness on
SET among secondary school girls in South Africa. Girls participated
in hands-on high-tech rapid prototyping environment of a fabrication
laboratory that was aimed at stimulating creativity and innovation as
part of a Fab Kids initiative. The Fab Kids intervention is about
creating a SET pipeline as part of the Young Engineers and Scientists
of Africa Initiative.The methodology was based on a real world
situation and a hands-on approach. In the process, participants
acquired a number of skills including computer-aided design,
research skills, communication skills, teamwork skills, technical
drawing skills, writing skills and problem-solving skills. Exposure to
technology enhanced the girls- confidence in being able to handle
technology-related tasks.
Abstract: There are a number of different cars for transferring hundreds of close contacts of swine influenza patients to hospital, and we need to carefully assign the passengers to those cars in order to minimize the risk of influenza spreading during transportation. The paper presents an approach to straightforward obtain the optimal solution of the relaxed problems, and develops two iterative improvement algorithms to effectively tackle the general problem.
Abstract: The overall objective of this research is a strain
improvement technology for efficient pectinase production. A novel
cells cultivation technology by immobilization of fungal cells has
been studied in long time continuous fermentations. Immobilization
was achieved by using of new material for absorption of stores of
immobilized cultures which was for the first time used for
immobilization of microorganisms. Effects of various conditions of
nitrogen and carbon nutrition on the biosynthesis of pectolytic
enzymes in Aspergillus awamori 1-8 strain were studied. Proposed
cultivation technology along with optimization of media components
for pectinase overproduction led to increased pectinase productivity
in Aspergillus awamori 1-8 from 7 to 8 times. Proposed technology
can be applied successfully for production of major industrial
enzymes such as α-amylase, protease, collagenase etc.
Abstract: Expression data analysis is based mostly on the
statistical approaches that are indispensable for the study of
biological systems. Large amounts of multidimensional data resulting
from the high-throughput technologies are not completely served by
biostatistical techniques and are usually complemented with visual,
knowledge discovery and other computational tools. In many cases,
in biological systems we only speculate on the processes that are
causing the changes, and it is the visual explorative analysis of data
during which a hypothesis is formed. We would like to show the
usability of multidimensional visualization tools and promote their
use in life sciences. We survey and show some of the
multidimensional visualization tools in the process of data
exploration, such as parallel coordinates and radviz and we extend
them by combining them with the self-organizing map algorithm. We
use a time course data set of transitional cell carcinoma of the bladder
in our examples. Analysis of data with these tools has the potential to
uncover additional relationships and non-trivial structures.
Abstract: In mechanical and environmental engineering, mixed
convection is a frequently encountered thermal fluid phenomenon
which exists in atmospheric environment, urban canopy flows, ocean
currents, gas turbines, heat exchangers, and computer chip cooling
systems etc... . This paper deals with a numerical investigation of
mixed convection in a vertical heated channel. This flow results from
the mixing of the up-going fluid along walls of the channel with the
one issued from a flat nozzle located in its entry section. The fluiddynamic
and heat-transfer characteristics of vented vertical channels
are investigated for constant heat-flux boundary conditions, a
Rayleigh number equal to 2.57 1010, for two jet Reynolds number
Re=3 103 and 2104 and the aspect ratio in the 8-20 range. The system
of governing equations is solved with a finite volumes method and an
implicit scheme. The obtained results show that the turbulence and
the jet-wall interaction activate the heat transfer, as does the drive of
ambient air by the jet. For low Reynolds number Re=3 103, the
increase of the aspect Ratio enhances the heat transfer of about 3%,
however; for Re=2 104, the heat transfer enhancement is of about
12%. The numerical velocity, pressure and temperature fields are
post-processed to compute the quantities of engineering interest such
as the induced mass flow rate, and average Nusselt number, in terms
of Rayleigh, Reynolds numbers and dimensionless geometric
parameters are presented.
Abstract: Starting from a biologically inspired framework, Gabor filters were built up from retinal filters via LMSE algorithms. Asubset of retinal filter kernels was chosen to form a particular Gabor filter by using a weighted sum. One-dimensional optimization approaches were shown to be inappropriate for the problem. All model parameters were fixed with biological or image processing constraints. Detailed analysis of the optimization procedure led to the introduction of a minimization constraint. Finally, quantization of weighting factors was investigated. This resulted in an optimized cascaded structure of a Gabor filter bank implementation with lower computational cost.
Abstract: Natural organic matter (NOM) is heterogeneous
mixture of organic compounds that enter the water media from
animal and plant remains, domestic and industrial wastes.
Researches showed that NOM is likely precursor material for
disinfection by products (DBPs). Chlorine very commenly used for
disinfection purposes and NOM and chlorine reacts then
Trihalomethane (THM) and Haloacetic acids (HAAs) which are
cancerogenics for human health are produced. The aim of the study is
to search NOM removal by enhanced coagulation from drinking
water source of Eskisehir which is supplied from Porsuk Dam.
Recently, Porsuk dam water is getting highly polluted and therefore
NOM concentration is increasing. Enhanced coagulation studies were
evaluated by measurement of Dissolved Organic Carbon (DOC), UV
absorbance at 254 nm (UV254), and different trihalomethane
formation potential (THMFP) tests. Results of jar test experiments
showed that NOM can be removed from water about 40-50 % of
efficiency by enhanced coagulation. Optimum coagulant type and
coagulant dosages were determined using FeCl3 and Alum.
Abstract: In this paper the strength of adhesive joint under
tension and bending is discussed on the basis of intensity of
singular stress by the application of FEM. A useful method is
presented with focusing on the stress at the edge of interface
between the adhesive and adherent obtained by FEM. After
analyzing the adhesive joint strength with all material
combinations, it is found that to improve the interface strength,
thin adhesive layers are desirable because the intensity of
singular stress decreases with decreasing the thickness.