Abstract: Vehicle suspension design must fulfill
some conflicting criteria. Among those is ride comfort
which is attained by minimizing the acceleration
transmitted to the sprung mass, via suspension spring
and damper. Also good handling of a vehicle is a
desirable property which requires stiff suspension and
therefore is in contrast with a vehicle with good ride.
Among the other desirable features of a suspension is
the minimization of the maximum travel of suspension.
This travel which is called suspension working space in
vehicle dynamics literature is also a design constraint
and it favors good ride. In this research a full car 8
degrees of freedom model has been developed and the
three above mentioned criteria, namely: ride, handling
and working space has been adopted as objective
functions. The Multi Objective Programming (MOP)
discipline has been used to find the Pareto Front and
some reasoning used to chose a design point between
these non dominated points of Pareto Front.
Abstract: The chemical degradation of dieldrin in ferric
sulfide and iron powder aqueous suspension was investigated
in laboratory batch type experiments. To identify the reaction
mechanism, reduced copper was used as reductant. More than
90% of dieldrin was degraded using both reaction systems after
29 days. Initial degradation rate of the pesticide using ferric
sulfide was superior to that using iron powder. The reaction
schemes were completely dissimilar even though the ferric ion
plays an important role in both reaction systems. In the case of
metallic iron powder, dieldrin undergoes partial dechlorination.
This reaction proceeded by reductive hydrodechlorination with
the generation of H+, which arise by oxidation of ferric iron.
This reductive reaction was accelerated by reductant but
mono-dechlorination intermediates were accumulated. On the
other hand, oxidative degradation was observed in the reaction
with ferric sulfide, and the stable chemical structure of dieldrin
was decomposed into water-soluble intermediates. These
reaction intermediates have no chemical structure of drin class.
This dehalogenation reaction assumes to occur via the adsorbed
hydroxyl radial generated on the surface of ferric sulfide.
Abstract: In this paper, an estimation accuracy of multiple moving
talker tracking using a microphone array is improved. The tracking
can be achieved by the adaptive method in which two algorithms are integrated, namely, the PAST (Projection Approximation Subspace
Tracking) algorithm and the IPLS (Interior Point Least Square) algorithm. When either talker begins to speak again after a silent
period, an appropriate feasible region for an evaluation function of
the IPLS algorithm might not be set. Then, the tracking fails due to the incorrect updating. Therefore, if an increment of the number of
active talkers is detected, the feasible region must be reset. Then, a low cost realization is required for the high speed tracking and a high
accuracy realization is desired for the precise tracking. In this paper,
the directions roughly estimated using the delayed-sum-array method
are used for the resetting. Several results of experiments performed in
an actual room environment show the effectiveness of the proposed method.
Abstract: The world economic crises and budget constraints
have caused authorities, especially those in developing countries, to
rationalize water quality monitoring activities. Rationalization
consists of reducing the number of monitoring sites, the number of
samples, and/or the number of water quality variables measured. The
reduction in water quality variables is usually based on correlation. If
two variables exhibit high correlation, it is an indication that some of
the information produced may be redundant. Consequently, one
variable can be discontinued, and the other continues to be measured.
Later, the ordinary least squares (OLS) regression technique is
employed to reconstitute information about discontinued variable by
using the continuously measured one as an explanatory variable. In
this paper, two record extension techniques are employed to
reconstitute information about discontinued water quality variables,
the OLS and the Line of Organic Correlation (LOC). An empirical
experiment is conducted using water quality records from the Nile
Delta water quality monitoring network in Egypt. The record
extension techniques are compared for their ability to predict
different statistical parameters of the discontinued variables. Results
show that the OLS is better at estimating individual water quality
records. However, results indicate an underestimation of the variance
in the extended records. The LOC technique is superior in preserving
characteristics of the entire distribution and avoids underestimation
of the variance. It is concluded from this study that the OLS can be
used for the substitution of missing values, while LOC is preferable
for inferring statements about the probability distribution.
Abstract: Existing literature ondesign reasoning seems to give
either one sided accounts on expert design behaviour based on
internal processing. In the same way ecological theoriesseem to
focus one sidedly on external elementsthat result in a lack of unifying
design cognition theory. Although current extended design cognition
studies acknowledge the intellectual interaction between internal and
external resources, there still seems to be insufficient understanding
of the complexities involved in such interactive processes. As
such,this paper proposes a novelmulti-directional model for design
researchers tomap the complex and dynamic conduct controlling
behaviour in which both the computational and ecological
perspectives are integrated in a vertical manner. A clear distinction
between identified intentional and emerging physical drivers, and
relationships between them during the early phases of experts- design
process, is demonstrated by presenting a case study in which the
model was employed.
Abstract: According to the statistics, the prevalence of congenital hearing loss in Taiwan is approximately six thousandths; furthermore, one thousandths of infants have severe hearing impairment. Hearing ability during infancy has significant impact in the development of children-s oral expressions, language maturity, cognitive performance, education ability and social behaviors in the future. Although most children born with hearing impairment have sensorineural hearing loss, almost every child more or less still retains some residual hearing. If provided with a hearing aid or cochlear implant (a bionic ear) timely in addition to hearing speech training, even severely hearing-impaired children can still learn to talk. On the other hand, those who failed to be diagnosed and thus unable to begin hearing and speech rehabilitations on a timely manner might lose an important opportunity to live a complete and healthy life. Eventually, the lack of hearing and speaking ability will affect the development of both mental and physical functions, intelligence, and social adaptability. Not only will this problem result in an irreparable regret to the hearing-impaired child for the life time, but also create a heavy burden for the family and society. Therefore, it is necessary to establish a set of computer-assisted predictive model that can accurately detect and help diagnose newborn hearing loss so that early interventions can be provided timely to eliminate waste of medical resources. This study uses information from the neonatal database of the case hospital as the subjects, adopting two different analysis methods of using support vector machine (SVM) for model predictions and using logistic regression to conduct factor screening prior to model predictions in SVM to examine the results. The results indicate that prediction accuracy is as high as 96.43% when the factors are screened and selected through logistic regression. Hence, the model constructed in this study will have real help in clinical diagnosis for the physicians and actually beneficial to the early interventions of newborn hearing impairment.
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.
Abstract: Electrical Discharge Machine (EDM) is especially
used for the manufacturing of 3-D complex geometry and hard
material parts that are extremely difficult-to-machine by conventional
machining processes. In this paper authors review the research work
carried out in the development of die-sinking EDM within the past
decades for the improvement of machining characteristics such as
Material Removal Rate, Surface Roughness and Tool Wear Ratio. In
this review various techniques reported by EDM researchers for
improving the machining characteristics have been categorized as
process parameters optimization, multi spark technique, powder
mixed EDM, servo control system and pulse discriminating. At the
end, flexible machine controller is suggested for Die Sinking EDM to
enhance the machining characteristics and to achieve high-level
automation. Thus, die sinking EDM can be integrated with Computer
Integrated Manufacturing environment as a need of agile
manufacturing systems.
Abstract: The incidence of mechanical fracture of an
automobile piston rings prompted development of fracture analysis
method on this case. The three rings (two compression rings and one
oil ring) were smashed into several parts during the power-test (after
manufacturing the engine) causing piston and liner to be damaged.
The radial and oblique cracking happened on the failed piston rings.
The aim of the fracture mechanics simulations presented in this paper
was the calculation of particular effective fracture mechanics
parameters, such as J-integrals and stress intensity factors. Crack
propagation angles were calculated as well. Two-dimensional
fracture analysis of the first compression ring has been developed in
this paper using ABAQUS CAE6.5-1 software. Moreover, SEM
fractography was developed on fracture surfaces and is discussed in
this paper. Results of numerical calculations constitute the basis for
further research on real object.
Abstract: with increasing circuits- complexity and demand to
use portable devices, power consumption is one of the most
important parameters these days. Full adders are the basic block of
many circuits. Therefore reducing power consumption in full adders
is very important in low power circuits. One of the most powerconsuming
modules in full adders is XOR/XNOR circuit. This paper
presents two new full adders based on two new logic approaches. The
proposed logic approaches use one XOR or XNOR gate to implement
a full adder cell. Therefore, delay and power will be decreased. Using
two new approaches and two XOR and XNOR gates, two new full
adders have been implemented in this paper. Simulations are carried
out by HSPICE in 0.18μm bulk technology with 1.8V supply voltage.
The results show that the ten-transistors proposed full adder has 12%
less power consumption and is 5% faster in comparison to MB12T
full adder. 9T is more efficient in area and is 24% better than similar
10T full adder in term of power consumption. The main drawback of
the proposed circuits is output threshold loss problem.
Abstract: Distance education program is a dimension of contemporary and new education technologies. Concepts and applications in this field are the results of a series of educational demands and developments in various communication and education technologies. Distance education applications have some conceptual bases. These are creating new education opportunities, realizing work-education unity, getting democratic in education, lifelong education, tendency to individual matters, effective use of institutions, integration of technology and education, tendency to individual and social needs, taking three dimensional integration as the main principle (publishing, printed materials and face to face education), reaching maximum mass, individual and mass education integrity and education demand and financial matters balance. Economics, Business Administration and Open Education faculties, which have been giving education within Anadolu University since 1982 in Turkey, are carrying on education with nearly 1.000.000 students. The aim of this study is to determine organizational commitment levels of students who have been studying at Anadolu University Economics, Business Administration and Open Education faculties in the scope of affective, continuance and nominative commitment in Allen&Meyer model. In the study, organizational commitment of the Economics, Business Administration and Open Education faculty students, who are receiving education by means of distance education, to their faculties is dealt after introducing Anadolu University Distance Education system which gives higher education via distance education method in Turkey. In order to increase the success level of faculties it is required for students to have high level of organizational commitment to their faculties. A questionnaire has been applied by using “Organizational Commitment Scale", developed by Meyer&Allen to determine organizational commitments of Economics, Business Administration and Open Education students. Organizational commitment is dealt with as affective, continuance and nominative commitment. The questionnaire was applied face to face to randomly chosen 500 students living in Eskişehir and the data was downloaded to the computer by using SPSS program and the results were analyzed in terms of demographic features (gender, age, marital status, years of study, work and income level) of students by using frequency test, ttest and ANOVA test. As a result of these analyses, when the comments of Open Education Faculty students on levels of affective, continuance and nominative commitment to their faculties were examined, it has been revealed that continuance commitment level has the highest rate. Among the female participants; continuance commitment is high in the age range of 30-40, for normative commitment it is 17-22. However no dominant age range was defined for affective commitment. Regarding the marital status; continuance commitment average is higher among married participants; but nominative affective commitment average is higher among single participants. As to the years of study, affective and continuance commitment is higher among senior students while normative commitment is higher among junior students. Moreover; in terms of continuance, affective and normative commitment, those who do not work and have low income have higher level of all there commitment types than those who work and have relatively high income.
Abstract: The practical implementation of audio-video coupled speech recognition systems is mainly limited by the hardware complexity to integrate two radically different information capturing devices with good temporal synchronisation. In this paper, we propose a solution based on a smart CMOS image sensor in order to simplify the hardware integration difficulties. By using on-chip image processing, this smart sensor can calculate in real time the X/Y projections of the captured image. This on-chip projection reduces considerably the volume of the output data. This data-volume reduction permits a transmission of the condensed visual information via the same audio channel by using a stereophonic input available on most of the standard computation devices such as PC, PDA and mobile phones. A prototype called VMIKE (Visio-Microphone) has been designed and realised by using standard 0.35um CMOS technology. A preliminary experiment gives encouraged results. Its efficiency will be further investigated in a large variety of applications such as biometrics, speech recognition in noisy environments, and vocal control for military or disabled persons, etc.
Abstract: This paper describes design of a digital feedback loop
for a low switching frequency dc-dc switching converters. Low
switching frequencies were selected in this design. A look up table
for the digital PID (proportional integrator differentiator)
compensator was implemented using Altera Stratix II with built-in
ADC (analog-to-digital converter) to achieve this hardware
realization. Design guidelines are given for the PID compensator,
high frequency DPWM (digital pulse width modulator) and moving
average filter.
Abstract: Groundlessness of application probability-statistic methods are especially shown at an early stage of the aviation GTE technical condition diagnosing, when the volume of the information has property of the fuzzy, limitations, uncertainty and efficiency of application of new technology Soft computing at these diagnosing stages by using the fuzzy logic and neural networks methods. It is made training with high accuracy of multiple linear and nonlinear models (the regression equations) received on the statistical fuzzy data basis. At the information sufficiency it is offered to use recurrent algorithm of aviation GTE technical condition identification on measurements of input and output parameters of the multiple linear and nonlinear generalized models at presence of noise measured (the new recursive least squares method (LSM)). As application of the given technique the estimation of the new operating aviation engine D30KU-154 technical condition at height H=10600 m was made.
Abstract: In this paper dynamics of a vapour bubble generated
due to a local energy input inside a vertical rigid cylinder and in the
absence of buoyancy forces is investigated. Different ratios of the
diameter of the rigid cylinder to the maximum radius of the bubble
are considered. The Boundary Integral Equation Method is employed
for numerical simulation of the problem. 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. Results also show that
existence of a deposit rib inside the vertical rigid cylinder slightly
increases the life time of the bubble. 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: This study realizes an empirical investigation of main factors to develop an accounting career, stereotypes on accountants and accounting and perceptions on future career path for a sample of master students in accounting. The research provides some insight into what master students consider when choosing their future career paths. The most important two reasons chosen by students were “career opportunities" and “future earnings. They see accounting as structured, governed by conformity, requiring skills in working with numbers, monotonous, accurate, more efficient than effective but also absorbing, interesting and involving a certain degree of novelty. Although these students plan to start their careers in a multinational or accounting/audit firm, most of those plan to leave after five years. It resulted that women value more flexibility and time requiring special attention in retention policies practiced by firms.
Abstract: This paper proposes a new technique for improving
the efficiency of software testing, which is based on a conventional
attempt to reduce test cases that have to be tested for any given
software. The approach utilizes the advantage of Regression Testing
where fewer test cases would lessen time consumption of the testing
as a whole. The technique also offers a means to perform test case
generation automatically. Compared to one of the techniques in the
literature where the tester has no option but to perform the test case
generation manually, the proposed technique provides a better
option. As for the test cases reduction, the technique uses simple
algebraic conditions to assign fixed values to variables (Maximum,
minimum and constant variables). By doing this, the variables values
would be limited within a definite range, resulting in fewer numbers
of possible test cases to process. The technique can also be used in
program loops and arrays.
Abstract: The main purpose of this study was to determine the predictors of academic achievement of student Information and Communications Technologies (ICT) teachers with different learning styles. Participants were 148 student ICT teachers from Ankara University. Participants were asked to fill out a personal information sheet, the Turkish version of Kolb-s Learning Style Inventory, Weinstein-s Learning and Study Strategies Inventory, Schommer's Epistemological Beliefs Questionnaire, and Eysenck-s Personality Questionnaire. Stepwise regression analyses showed that the statistically significant predictors of the academic achievement of the accommodators were attitudes and high school GPAs; of the divergers was anxiety; of the convergers were gender, epistemological beliefs, and motivation; and of the assimilators were gender, personality, and test strategies. Implications for ICT teaching-learning processes and teacher education are discussed.
Abstract: This article concerns the presentation of an integrated
method for detection of steganographic content embedded by new
unknown programs. The method is based on data mining and
aggregated hypothesis testing. The article contains the theoretical
basics used to deploy the proposed detection system and the
description of improvement proposed for the basic system idea.
Further main results of experiments and implementation details are
collected and described. Finally example results of the tests are
presented.
Abstract: The aim of this study was to investigate the effects of
supplementing the diluent of roosters' semen with different levels of
olive oil on motility, viability, morphology and acrosome integrity of
chicken spermatozoa after in vitro storage for up to 72 h. Semen was
collected from 60 White Layer males (62 wk of age) kept in
separated floor pens and randomly divided into six treatment groups
(10 males in each group). Experimental groups were as follows: T1
:fresh semen, T2 : semen extended 1:1 with Al – Daraji 2 diluent
(AD2D) alone, T3 – T6 :semen samples extended 1:1 with AD2D
supplemented with 2 ml, 4 ml, 6 ml or 8 ml of olive oil / 100 ml of
diluent, respectively. Semen samples were then stored at 5 °C for 24
h, 48 h or 72 h. There was a clear influence of diluent
supplementation with olive oil on the spermatozoa motility profile;
olive oil groups (T3, T4, T5 and T6) recorded the highest scores of
mass activity and individual motility during all storage periods
compared to T1 and T2 groups. In addition, the inclusion of olive oil
into semen diluent (T3, T4, T5 and T6) gave significantly higher
percentages of viable spermatozoa, normal morphologically
spermatozoa and intact acrosomes irrespective of storage period.
These results clearly show that supplementation the diluent of
roosters' semen with olive oil can improve semen quality when
semen samples in vitro stored at 5 °C for up to 72 h.