Abstract: Three dimensional non-Interlaced carbon fibre
reinforced silicon carbide (3-D-Cf/SiC) composites with pyrocarbon
interphase were fabricated using isothermal chemical vapor
infiltration (ICVI) combined with polymer impregnation pyrolysis
(PIP) process. Polysilazane (PSZ) is used as a preceramic polymer to
obtain silicon carbide matrix. Thermo gravimetric analysis (TGA),
Infrared spectroscopic analysis (IR) and X-ray diffraction (XRD)
analysis were carried out on PSZ pyrolysed at different temperatures
to understand the pyrolysis and obtaining the optimum pyrolysing
condition to yield β-SiC phase. The density of the composites was
1.94 g cm-3 after the 3-D carbon preform was SiC infiltrated for 280 h
with one intermediate polysilazane pre-ceramic PIP process.
Mechanical properties of the composite materials were investigated
under tensile, flexural, shear and impact loading. The values of
tensile strength were 200 MPa at room temperature (RT) and 195
MPa at 500°C in air. The average RT flexural strength was 243 MPa.
The lower flexural strength of these composites is because of the
porosity. The fracture toughness obtained from single edge notched
beam (SENB) technique was 39 MPa.m1/2. The work of fracture
obtained from the load-displacement curve of SENB test was 22.8
kJ.m-2. The composites exhibited excellent impact resistance and the
dynamic fracture toughness of 44.8 kJ.m-2 is achieved as determined
from instrumented Charpy impact test. The shear strength of the
composite was 93 MPa, which is significantly higher compared 2-D
Cf/SiC composites. Microstructure evaluation of fracture surfaces
revealed the signatures of fracture processes and showed good
support for the higher toughness obtained.
Abstract: This study aimed at designing and developing a
mechanical force gauge for the square watermelon mold for the first
time. It also tried to introduce the square watermelon characteristics
and its production limitations. The mechanical force gauge
performance and the product itself were also described. There are
three main designable gauge models: a. hydraulic gauge, b. strain
gauge, and c. mechanical gauge. The advantage of the hydraulic
model is that it instantly displays the pressure and thus the force
exerted by the melon. However, considering the inability to measure
forces at all directions, complicated development, high cost, possible
hydraulic fluid leak into the fruit chamber and the possible influence
of increased ambient temperature on the fluid pressure, the
development of this gauge was overruled. The second choice was to
calculate pressure using the direct force a strain gauge. The main
advantage of these strain gauges over spring types is their high
precision in measurements; but with regard to the lack of conformity
of strain gauge working range with water melon growth, calculations
were faced with problems. Finally the mechanical pressure gauge has
advantages, including the ability to measured forces and pressures on
the mold surface during melon growth; the ability to display the peak
forces; the ability to produce melon growth graph thanks to its
continuous force measurements; the conformity of its manufacturing
materials with the required physical conditions of melon growth; high
air conditioning capability; the ability to permit sunlight reaches the
melon rind (no yellowish skin and quality loss); fast and
straightforward calibration; no damages to the product during
assembling and disassembling; visual check capability of the product
within the mold; applicable to all growth environments (field,
greenhouses, etc.); simple process; low costs and so forth.
Abstract: This paper presents the performance state analysis of
Self-Excited Induction Generator (SEIG) using Artificial Bee Colony
(ABC) optimization technique. The total admittance of the induction
machine is minimized to calculate the frequency and magnetizing
reactance corresponding to any rotor speed, load impedance and
excitation capacitance. The performance of SEIG is calculated using
the optimized parameter found. The results obtained by ABC
algorithm are compared with results from numerical method. The
results obtained coincide with the numerical method results. This
technique proves to be efficient in solving nonlinear constrained
optimization problems and analyzing the performance of SEIG.
Abstract: Web search engines are designed to retrieve and
extract the information in the web databases and to return dynamic
web pages. The Semantic Web is an extension of the current web in
which it includes semantic content in web pages. The main goal of
semantic web is to promote the quality of the current web by
changing its contents into machine understandable form. Therefore,
the milestone of semantic web is to have semantic level information
in the web. Nowadays, people use different keyword- based search
engines to find the relevant information they need from the web.
But many of the words are polysemous. When these words are
used to query a search engine, it displays the Search Result Records
(SRRs) with different meanings. The SRRs with similar meanings are
grouped together based on Word Sense Disambiguation (WSD). In
addition to that semantic annotation is also performed to improve the
efficiency of search result records. Semantic Annotation is the
process of adding the semantic metadata to web resources. Thus the
grouped SRRs are annotated and generate a summary which
describes the information in SRRs. But the automatic semantic
annotation is a significant challenge in the semantic web. Here
ontology and knowledge based representation are used to annotate
the web pages.
Abstract: Male factor infertility due to endocrine disturbances
such as abnormalities in prolactin levels are encountered in a
significant proportion. This case control study was carried out to
determine the effects of prolactin on the male reproductive tract,
using 200 male white rats. The rats were maintained as the control
group (G1), hypoprolactinaemic group (G2), 3 hyperprolactinaemic
groups induced using oral largactil (G3), low dose fluphenazine (G4)
and high dose fluphenazine (G5). After 100 days, rats were subjected
to serum prolactin (PRL) level measurements and for basic seminal
fluid analysis (BSA). The difference between serum PRL
concentrations of rats in G2, G3, G4 and G5 as compared to the
control group were highly significant by Student’s t-test (p
Abstract: As currently various portable devices were launched,
smart business conducted using them became common. Since smart
business can use company-internal resources in an exlternal remote
place, user authentication that can identify authentic users is an
important factor. Commonly used user authentication is a method of
using user ID and Password. In the user authentication using ID and
Password, the user should see and enter authentication information
him or her. In this user authentication system depending on the user’s
vision, there is the threat of password leaks through snooping in the
process which the user enters his or her authentication information.
This study designed and produced a user authentication module
using an actuator to respond to the snooping threat.
Abstract: With the rapid progress of modern cities, the railway
construction must be developing quickly in China.As a typical
high-density country, shopping center on the subway should be one
important factor during the process of urban development. The paper
discusses the influence of the layout of shopping center on the subway,
and put it in the time and space’s axis of Shanghai urban development.
We usethe digital technology to establish the database of relevant
information. And then get the change role about shopping center on
subway in Shanghaiby the Kernel density estimate.The result shows
the development of shopping center on subway has a relationship with
local economic strength, population size, policysupport, and city
construction. And the suburbanization trend of shopping center would
be increasingly significant.By this case research, we could see the
Kernel density estimate is an efficient analysis method on the spatial
layout. It could reveal the characters of layout form of shopping center
on subway in essence. And it can also be applied to the other research
of space form.
Abstract: The purposes of this research were to study concepts
and strategies of human resource development in the automotive
manufacturers and to articulate the proposals against the government
about the human resource development for automotive industry. In
the present study, qualitative study was an in-depth interview in
which the qualitative data were collected from the executive or the
executive of human resource division from five automotive
companies - Toyota Motor (Thailand) Co., Ltd., Nissan Motor
(Thailand) Co., Ltd., Mitsubishi Motors (Thailand) Co., Ltd., Honda
Automobile (Thailand) Co., Ltd., and Suzuki Motor (Thailand) Co.,
Ltd. Qualitative data analysis was performed by using inter-coder
agreement technique. The research findings were as follows:
The external factors included the current conditions of the
automotive industry, government’s policy related to the automotive
industry, technology, labor market and human resource development
systems of the country. The internal factors included management,
productive management, organizational strategies, leadership,
organizational culture and philosophy of human resource
development. These factors were affected to the different concept of
human resources development -the traditional human resource
development and the strategies of human resource development. The
organization focuses on human resources as intellectual capital and
uses the strategies of human resource development in all
development processes. The strategies of human resource
development will enhance the ability of human resources in the
organization and the country.
Abstract: Lightning protection systems (LPS) for wind power
generation is becoming an important public issue. A serious damage
of blades, accidents where low-voltage and control circuit
breakdowns are frequently occur in many wind farms. A grounding
system is one of the most important components required for
appropriate LPSs in wind turbines WTs. Proper design of a wind
turbine grounding system is demanding and several factors for the
proper and effective implementation must taken into account. In this
paper proposed procedure of proper design of grounding systems for
a wind turbine was introduced. This procedure depends on measuring
of ground current of simulated wind farm under lightning taking into
consideration the soil ionization. The procedure also includes the
Ground Potential Rise (GPR) and the voltage distributions at ground
surface level and Touch potential. In particular, the contribution of
mitigating techniques, such as rings, rods and the proposed design
were investigated.
Abstract: The growth of wireless devices affects the availability
of limited frequencies or spectrum bands as it has been known that
spectrum bands are a natural resource that cannot be added.
Meanwhile, the licensed frequencies are idle most of the time.
Cognitive radio is one of the solutions to solve those problems.
Cognitive radio is a promising technology that allows the unlicensed
users known as secondary users (SUs) to access licensed bands
without making interference to licensed users or primary users (PUs).
As cloud computing has become popular in recent years, cognitive
radio networks (CRNs) can be integrated with cloud platform. One of
the important issues in CRNs is security. It becomes a problem since
CRNs use radio frequencies as a medium for transmitting and CRNs
share the same issues with wireless communication systems. Another
critical issue in CRNs is performance. Security has adverse effect to
performance and there are trade-offs between them. The goal of this
paper is to investigate the performance related to security trade-off in
CRNs with supporting cloud platforms. Furthermore, Queuing
Network Models with preemptive resume and preemptive repeat
identical priority are applied in this project to measure the impact of
security to performance in CRNs with or without cloud platform. The
generalized exponential (GE) type distribution is used to reflect the
bursty inter-arrival and service times at the servers. The results show
that the best performance is obtained when security is disabled and
cloud platform is enabled.
Abstract: Despite four years of study in the tourism industry, the
Bachelor’s graduates cannot perform their jobs as experienced tour
guides. This research aimed to develop French teaching and studying
for Tourism with two main purposes: to analyze ‘Moves’ used in oral
presentations at tourist attraction; and to study content in guiding
presentations or 'Guide Speak'. The study employed audio recording
of these presentations as an interview method in authentic situations,
having four tour guides as respondents and information providers.
The data was analyzed via moves and content analysis. The results
found that there were eight Moves used; namely, Welcoming,
Introducing oneself, Drawing someone’s attention, Giving
information, Explaining, Highlighting, Persuading and Saying
goodbye. In terms of content, the information being presented
covered the outstanding characteristics of the places and wellintegrated
with other related content. The findings were used as
guidelines for curriculum development; in particular, the core content
and the presentation forming the basis for students to meet the
standard requirements of the labor-market and professional schemes.
Abstract: This paper presents the voltage problem location
classification using performance of Least Squares Support Vector
Machine (LS-SVM) and Learning Vector Quantization (LVQ) in
electrical power system for proper voltage problem location
implemented by IEEE 39 bus New- England. The data was collected
from the time domain simulation by using Power System Analysis
Toolbox (PSAT). Outputs from simulation data such as voltage, phase
angle, real power and reactive power were taken as input to estimate
voltage stability at particular buses based on Power Transfer Stability
Index (PTSI).The simulation data was carried out on the IEEE 39 bus
test system by considering load bus increased on the system. To verify
of the proposed LS-SVM its performance was compared to Learning
Vector Quantization (LVQ). The results showed that LS-SVM is faster
and better as compared to LVQ. The results also demonstrated that the
LS-SVM was estimated by 0% misclassification whereas LVQ had
7.69% misclassification.
Abstract: Recently, to cope with the rapidly changing
construction trend with aging infrastructures, modular bridge
technology has been studied actively. Modular bridge is easily
constructed by assembling standardized precast structure members in
the field. It will be possible to construct rapidly and reduce
construction cost efficiently. However, the shape of the transverse
connection of T-type girder newly developed between the segmented
modules is not verified. Therefore, the verification of the connection
shape is needed. In this study, shape of the modular T-girder bridge
transverse connection was analyzed by finite element model that was
verified in study which was verified model of transverse connection
using Abaqus. Connection angle was chosen as the parameter. The
result of analyses showed that optimal value of angle is 130 degree.
Abstract: A blood pressure monitor or sphygmomanometer can
be either manual or automatic, employing respectively either the
auscultatory method or the oscillometric method.
The manual version of the sphygmomanometer involves an
inflatable cuff with a stethoscope adopted to detect the sounds
generated by the arterial walls to measure blood pressure in an artery.
An automatic sphygmomanometer can be effectively used to
monitor blood pressure through a pressure sensor, which detects
vibrations provoked by oscillations of the arterial walls.
The pressure sensor implemented in this device improves the
accuracy of the measurements taken.
Abstract: In the present study, M2 high speed steels were
fabricated by using electro-slag rapid remelting process. Carbide
structure was analysed and the fracture toughness and hardness were
also measured after austenitization treatment at 1190 and 1210oC
followed by tempering treatment at 535oC for billets with various
diameters from 16 to 60 mm. Electro-slag rapid remelting (ESRR)
process is an advanced ESR process combined by continuous casting
and successfully employed in this study to fabricate a sound M2 high
speed ingot. Three other kinds of commercial M2 high speed steels,
produced by traditional method, were also analysed for comparison.
Distribution and structure of eutectic carbides of the ESRR billet were
found to be comparable to those of commercial alloy and so was the
fracture toughness.
Abstract: Phase equilibria of AZ91D Mg alloys for
nonflammable use, containing Ca and Y, were carried out by using
FactSage® and FTLite database, which revealed that solid solution
treatment could be performed at temperatures from 400 to 450oC.
Solid solution treatment of AZ91D Mg alloy without Ca and Y was
successfully conducted at 420oC and supersaturated microstructure
with all beta phase resolved into matrix was obtained. In the case of
AZ91D Mg alloy with some Ca and Y; however, a little amount of
intermetallic particles were observed after solid solution treatment.
After solid solution treatment, each alloy was annealed at temperatures
of 180 and 200oC for time intervals from 1 min to 48 hrs and hardness
of each condition was measured by micro-Vickers method. Peak aging
conditions were deduced as at the temperature of 200oC for 10 hrs.
Abstract: The ever increasing amount of solid waste (SW)
generated which is exacerbated by lack of proper waste management
system is of growing concern worldwide and in major cities in
developing countries due to its social, economic and environmental
implications. This study attempts to describe the aspects of solid
waste management (SWM) in Adama, one of the fast urbanizing
cities in Ethiopia, and highlights the challenges thereof. Data were
gathered through interview supplemented by field observation and
self-administered questionnaire. Then, the data were analyzed using
the Statistical Package for Social Science (SPSS) software. In
addition, secondary data were gathered from documents. Findings
revealed that the current SWM practice couldn’t cope with the fast
urbanizing needs and the rapid population growth exhibited by the
city. Besides, major factors contributing to the inefficient system
were identified. The study would provide practical insights to
decision makers in developing a sustainable SWM system leading to
minimized risk in the city.
Abstract: Heating, cooling and lighting appliances in buildings
account for more than one third of the world’s primary energy
demand. Therefore, main components of the building heating systems
play an essential role in terms of energy consumption. In this context,
efficient energy and exergy utilization in HVAC-R systems has been
very essential, especially in developing energy policies towards
increasing efficiencies. The main objective of the present study is to
assess the performance of a family house with a volume of 326.7 m3
and a net floor area of 121 m2, located in the city of Izmir, Turkey in
terms of energetic, exergetic and sustainability aspects. The indoor
and exterior air temperatures are taken as 20°C and 1°C, respectively.
In the analysis and assessment, various metrics (indices or indicators)
such as exergetic efficiency, exergy flexibility ratio and sustainability
index are utilized. Two heating options (Case 1: condensing boiler
and Case 2: air heat pump) are considered for comparison purposes.
The total heat loss rate of the family house is determined to be
3770.72 W. The overall energy efficiencies of the studied cases are
calculated to be 49.4% for Case 1 and 54.7% for Case 2. The overall
exergy efficiencies, the flexibility factor and the sustainability index
of Cases 1 and 2 are computed to be around 3.3%, 0.17 and 1.034,
respectively.
Abstract: This study models the use of transcutaneous electrical
nerve stimulation on skin with a disk electrode in order to simulate
tissue damage. The current density distribution above a disk electrode
is known to be a dynamic and non-uniform quantity that is intensified
at the edges of the disk. The non-uniformity is subject to change
through using various electrode geometries or stimulation methods.
One of these methods known as edge-retarded stimulation has shown
to reduce this edge enhancement. Though progress has been made in
modeling the behavior of a disk electrode, little has been done to test
the validity of these models in simulating the actual heat transfer
from the electrode. This simulation uses finite element software to
couple the injection of current from a disk electrode to heat transfer
described by the Pennesbioheat transfer equation. An example
application of this model is studying an experimental form of
stimulation, known as edge-retarded stimulation. The edge-retarded
stimulation method will reduce the current density at the edges of the
electrode. It is hypothesized that reducing the current density edge
enhancement effect will, in turn, reduce temperature change and
tissue damage at the edges of these electrodes. This study tests this
hypothesis as a demonstration of the capabilities of this model. The
edge-retarded stimulation proved to be safer after this simulation. It is
shown that temperature change and the fraction of tissue necrosis is
much greater in the square wave stimulation. These results bring
implications for changes of procedures in transcutaneous electrical
nerve stimulation and transcutaneous spinal cord stimulation as well.
Abstract: In this paper the issue of dimensionality reduction is
investigated in finger vein recognition systems using kernel Principal
Component Analysis (KPCA). One aspect of KPCA is to find the
most appropriate kernel function on finger vein recognition as there
are several kernel functions which can be used within PCA-based
algorithms. In this paper, however, another side of PCA-based
algorithms -particularly KPCA- is investigated. The aspect of
dimension of feature vector in PCA-based algorithms is of
importance especially when it comes to the real-world applications
and usage of such algorithms. It means that a fixed dimension of
feature vector has to be set to reduce the dimension of the input and
output data and extract the features from them. Then a classifier is
performed to classify the data and make the final decision. We
analyze KPCA (Polynomial, Gaussian, and Laplacian) in details in
this paper and investigate the optimal feature extraction dimension in
finger vein recognition using KPCA.