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: 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: Azadirachta excelsa or locally known as sentang are
frequently used as a traditional medicine by diabetes patients in
Malaysia. However, less attention has been given to their toxicity
effect. Thus, the study is an attempt to examine the protective effect
of A. excelsa on the pancreas and to determine possible toxicity
mediated by the extract. Diabetes was induced experimentally in rats
by high-fat-diet for 16 weeks followed by intraperitoneal injection of
streptozotocin at dosage of 35 mg/kg of body weight. Declination of
the fasting blood glucose level was observed after continuous
administration of A. excelsa for 14 days twice daily. This is due to the
refining structure of the pancreas. However, surprisingly, the plant
extract reduced the leukocytes, erythrocytes, hemoglobin, MCHC and
lymphocytes. In addition, the rat treated with the plant extract
exhibited increment in AST and eosinocytes level. Overall, the
finding shows that A. excelsa possesses antidiabetic activity by
improving the structure of pancreatic islet of Langerhans but
involved in ameliorating of hematology and biochemical parameters.
Abstract: In this study, six bacterial isolates of a slightly
thermophilic organism from the Sg. Klah hot spring, Malaysia were
successfully isolated and designated as M7T55D1, M7T55D2,
M7T55D3, M7T53D1, M7T53D2 and M7T53D3 respectively. The
bacterial isolates were screened for their cellulose hydrolytic ability
on Carboxymethlycellulose agar medium. The isolated bacterial
strains were identified morphologically, biochemically and
molecularly with the aid of 16S rDNA sequencing. All of the bacteria
showed their optimum growth at a slightly alkaline pH of 7.5 with a
temperature of 55°C. All strains were Gram-negative, non-spore
forming type, strictly aerobic, catalase-positive and oxidase-positive
with the ability to produce thermostable cellulase. Based on BLASTn
results, bacterial isolates of M7T55D2 and M7T53D1 gave the
highest homology (97%) with similarity to Tepidimonas ignava while
isolates M7T55D1, M7T55D3, M7T53D2 and M7T53D3 showed
their closest homology (97%-98%) with Tepidimonas thermarum.
These cellulolytic thermophiles might have a commercial potential to
produce valuable thermostable cellulase.
Abstract: This paper presents the variation of the dynamic
characteristics of a spindle with the change of bearing preload. The
correlations between the variation of bearing preload and fundamental
modal parameters were first examined by conducting vibration tests on
physical spindle units. Experimental measurements show that the
dynamic compliance and damping ratio associated with the
dominating modes were affected to vary with variation of the bearing
preload. When the bearing preload was slightly deviated from a
standard value, the modal frequency and damping ability also vary to
different extent, which further enable the spindle to perform with
different compliance. For the spindle used in this study, a standard
preload value set on bearings would enable the spindle to behave a
higher stiffness as compared with others with a preload variation. This
characteristic can be served as a reference to examine the variation of
bearing preload of spindle in assemblage or operation.
Abstract: The purposes of this study were to design and find
users’ satisfaction after using the decision support system for tourism
northern part of Thailand, which can provide tourists touristic
information and plan their personal voyage. Such information can be
retrieved systematically based on personal budget and provinces. The
samples of this study were five experts and users 30 persons white
collars in Bangkok. This decision support system was designed via
ASP.NET. Its database was developed by using MySQL, for
administrators are able to effectively manage the database. The
application outcome revealed that the innovation works properly as
sought in objectives. Specialists and white collars in Bangkok have
evaluated the decision support system; the result was satisfactorily
positive.
Abstract: In order to evaluate the performance of a unified power
flow controller (UPFC), mathematical models for steady state and
dynamic analysis are to be developed. The steady state model is
mainly concerned with the incorporation of the UPFC in load flow
studies. Several load flow models for UPFC have been introduced
in literature, and one of the most reliable models is the decoupled
UPFC model. In spite of UPFC decoupled load flow model simplicity,
it is more robust compared to other UPFC load flow models and it
contains unique capabilities. Some shortcoming such as additional
set of nonlinear equations are to be solved separately after the load
flow solution is obtained. The aim of this study is to investigate the
different control strategies that can be realized in the decoupled load
flow model (individual control and combined control), and the impact
of the location of the UPFC in the network on its control parameters.
Abstract: Roof top rainwater harvesting (RWH) has been
carried out worldwide to provide an inexpensive source of water for
many people. This research aims at evaluating the potential of roof
top rain water harvesting as a resource in Jordan. For the purpose of
this work, two case studies at Al-Jubiha and Shafa-Badran districts in
Amman city were selected. All existing rooftops in both districts
were identified by digitizing 2012 satellite images of the two districts
using Google earth and ArcGIS tools. Rational method was used to
estimate the potential volume of rainwater that can be harvested from
the digitized rooftops. Results indicated that 1.17 and 0.526 MCM/yr
can be harvested in Al-Jubiha and Shafa-Badran districts,
respectively. This study should increase the attention to the
importance of implementing RWH technique in Jordanian residences
as a viable alternative for ensuring a continued source of non-potable
water.
Abstract: This study aims to examine the role of career
advancement and job security as predictors of employee commitment
to their organization. Data was collected from 580 frontline
employees attached to two departments of 29 luxury hotels in
Peninsular Malaysia. Statistical results using Partial Least Squares
technique provided support for the proposed hypotheses. In view of
the findings, theoretical and practical implications are discussed.
Abstract: High temperature deformation behavior of cast
Fe-20Cr-5Al alloy has been investigated in this study by performing
tensile and compression tests at temperatures from 1100 to 1200oC.
Rectangular ingots of which the dimensions were 300×300×100 in
millimeter were cast using vacuum induction melting. Phase
equilibrium was calculated using the FactSage®, thermodynamic
software and database. Tensile strength of cast Fe-20Cr-5Al alloy was
4 MPa at 1200oC. With temperature decreased, tensile strength
increased rapidly and reached up to 13 MPa at 1100oC. Elongation
also increased from 18 to 80% with temperature decreased from
1200oC to 1100oC. Microstructure observation revealed that M23C6
carbide was precipitated along the grain boundary and within the
matrix.
Abstract: In this paper, GSM signal strength was measured in
order to detect the type of the signal fading phenomenon using onedimensional
multilevel wavelet residual method and neural network
clustering to determine the average GSM signal strength received in
the study area. The wavelet residual method predicted that the GSM
signal experienced slow fading and attenuated with MSE of 3.875dB.
The neural network clustering revealed that mostly -75dB, -85dB and
-95dB were received. This means that the signal strength received in
the study is a weak signal.
Abstract: This study investigates the effect of moisture
conditioning on the Indirect Tensile Strength (ITS) of asphalt
concrete. As a first step, cylindrical samples of 100 mm diameter and
50 mm thick were prepared using a Superpave gyratory compactor.
Next, the samples were conditioned using Moisture Induced
Susceptibility Test (MIST) device at different numbers of moisture
conditioning cycles. In the MIST device, samples are subjected water
pressure through the sample pores cyclically. The MIST conditioned
samples were tested for ITS. Results show that the ITS does not
change significantly with MIST conditioning at the specific pressure
and cycles adopted in this study.
Abstract: Thermal insulation materials based on natural fibers
represent a very promising area of materials based on natural easy
renewable row sources. These materials may be in terms of the
properties of most competing synthetic insulations, but show
somewhat higher moisture sensitivity and thermal insulation
properties are strongly influenced by the density and orientation of
fibers. The paper described the problem of hygrothermal behavior of
thermal insulation materials based on natural plant and animal fibers.
This is especially the dependence of the thermal properties of these
materials on the type of fiber, bulk density, temperature, moisture and
the fiber orientation.
Abstract: Electronic market place plays an important
intermediary role for connecting dealers and retail customers. The
main aim of this paper is to design a value co-creation model in
used-car auctions. More specifically, the study has been designed in
order to describe the process of value co-creation in used-car auctions,
to explore the co-created values in used-car auctions, and finally
conclude the paper indicating the future research directions. Our
analysis shows that economic values as well as non-economic values
are co-created in used-car auctions. In addition, this paper contributes
to the academic society broadening the view of value co-creation in
service science.
Abstract: The following case study presents the management of
stage III Differentiated Thyroid Cancer (DTC) patient in an NHS
hospital in London, UK during period of 2004-2005.
Abstract: Disasters are quite experienced in our days. They are
caused by floods, landslides, and building fires that is the main
objective of this study. To cope with these unexpected events,
precautions must be taken to protect human lives. The emphasis on
disposal work focuses on the resolution of the evacuation problem in
case of no-notice disaster. The problem of evacuation is listed as a
dynamic network flow problem. Particularly, we model the
evacuation problem as an earliest arrival flow problem with load
dependent transit time. This problem is classified as NP-Hard. Our
challenge here is to propose a metaheuristic solution for solving the
evacuation problem. We define our objective as the maximization of
evacuees during earliest periods of a time horizon T. The objective
provides the evacuation of persons as soon as possible. We
performed an experimental study on emergency evacuation from the
tunisian children’s hospital. This work prompts us to look for
evacuation plans corresponding to several situations where the
network dynamically changes.
Abstract: Osteoporosis is a common multifactorial disease with
a strong genetic component characterized by reduced bone mass and
increased risk of fractures. Genetic factors play an important role in
the pathogenesis of osteoporosis. The aim of our study was to
identify the genotype and allele distribution of T245G polymorphism
in OPG gene in Slovak postmenopausal women. A total of 200
unrelated Slovak postmenopausal women with diagnosed
osteoporosis and 200 normal controls were genotyped for T245G
(rs3134069) polymorphism of OPG gene. Genotyping was performed
using the Custom Taqman®SNP Genotyping assays. Genotypes and
alleles frequencies showed no significant differences (p=0.5551;
p=0.6022). The results of the present study confirm the importance of
T245G polymorphism in OPG gene in the pathogenesis of
osteoporosis.
Abstract: The objectives of this research were to study the
influencing factors that contributed to the success of e-collaborative
in e-commerce of B2C (Business to Customer) business in Bangkok,
Thailand. The influencing factors included organization, people,
information technology and the process of e-collaborative. A
questionnaire was used to collect data from 200 small e-commerce
businesses and the path analysis was utilized as the tool for data
analysis.
By using the path analysis, it was revealed that the factors
concerning with organization, people and information technology
played an influence on e-collaborative process and the success of ecollaborative,
whereas the process of e-collaborative factor
manipulated its success. The findings suggested that B2C ecommerce
business in Thailand should opt in improvement approach
in terms of managerial structure, leaderships, staff’s skills and
knowledge, and investment of information technology in order to
capacitate higher efficiency of e-collaborative process that would
result in profit and competitive advantage.