Abstract: A novel simulation method to determine the
displacements of machine tools due to thermal factors is presented.
The specific characteristic of this method is the employment of
original CAD data from the design process chain, which is
interpreted by an algorithm in terms of geometry-based allocation of
convection and radiation parameters. Furthermore analogous models
relating to the thermal behaviour of machine elements are
automatically implemented, which were gained by extensive
experimental testing with thermography imaging. With this a
transient simulation of the thermal field and in series of the
displacement of the machine tool is possible simultaneously during
the design phase. This method was implemented and is already used
industrially in the design of machining centres in order to improve
the quality of herewith manufactured workpieces.
Abstract: A study was conducted to determine the diversity and
abundance of shorebird species habituating the mudflat area of Jeram
Beach and Remis Beach, Selangor, Peninsular Malaysia. Direct
observation technique (using binoculars and video camera) was
applied to record the presence of bird species in the sampling sites
from August 2013 until July 2014. A total of 32 species of shorebird
were recorded during both migratory and non-migratory seasons. Of
these, eleven species (48%) are migrants, six species (26%) have both
migrant and resident populations, four species (17%) are vagrants and
two species (9%) are residents. The compositions of the birds
differed significantly in all months (χ2 = 84.35, p < 0.001). There is a
significant difference in avian abundance between migratory and
non-migratory seasons (Mann-Whitney, t = 2.39, p = 0.036). The
avian abundance were differed significantly in Jeram and Remis
Beaches during migratory periods (t = 4.39, p = 0.001) but not during
non-migratory periods (t = 0.78, p = 0.456). Shorebird diversity was
also affected by tidal cycle. There is a significance difference
between high tide and low tide (Mann-Whitney, t = 78.0, p < 0.005).
Frequency of disturbance also affected the shorebird distribution
(Mann-Whitney, t = 57.0, p = 0.0134). Therefore, this study
concluded that tides and disturbances are two factors that affecting
temporal distribution of shorebird in mudflats area.
Abstract: This research aims to investigate callus induction,
somatic embryogenesis and indirect plant regeneration of Crassula
ovata (Mill.) Druce – the famous ornamental plant. Experiment no.1:
Callus induction was obtained from leaf and stem explants on
Murashige and Skoog (MS) medium supplemented with various plant
growth regulators (PGRs). Effects of different PGRs, plant
regeneration and subsequent plantlet conversion were also assessed.
Indirect plant regeneration was achieved from the callus of stem
explants by the addition of 1.5 mg/L Kinetin (KN) alone. Best shoot
induction was achieved (6.5 shoots/per explant) after 60 days. For
successful rooting, regenerated plantlets were sub-cultured on the
same MS media supplemented with 1.5 mg/L KN alone. The rooted
plantlets were acclimatized and the survival rate was 90%.
Experiment no.2: Results revealed that 0.5 mg/L 2,4-D alone and in
combination with 1.0 mg/L 6-Benzyladenine (BA) gave 89.8% callus
from the stem explants as compared to leaf explants. Callus
proliferation and somatic embryo formation were also evaluated by
‘Double Staining Method’ and different stages of somatic
embryogenesis were revealed by scanning electron microscope. Full
Strength MS medium produced the highest number (49.6%) of
cotyledonary stage somatic embryos (SEs). Mature cotyledonary
stage SEs developed into plantlets after 12 weeks of culture. Wellrooted
plantlets were successfully acclimatized at the survival rate of
85%. Indirectly regenerated plants did not show any detectable
variation in morphological and growth characteristics when
compared with the donor plant.
Abstract: This paper presents a method for the efficient
implementation of a unidirectional or bidirectional DC/DC converter.
The DC/DC converter is used essentially for energy exchange
between the low voltage service battery and a high voltage battery
commonly found in Electric Vehicle applications. In these
applications, apart from cost, efficiency of design is an important
characteristic. A useful way to reduce the size of electronic
equipment in the electric vehicles is proposed in this paper. The
technique simplifies the mechanical complexity and maximizes the
energy usage using the latest converter control techniques. Moreover
a bidirectional battery charger for hybrid electric vehicles is also
implemented in this paper. Several simulations on the test system
have been carried out in Matlab/Simulink environment. The results
exemplify the robustness of the proposed design methodology in case
of a 1.5 KW DC-DC converter.
Abstract: The study was conducted to produce case studies from
the Malaysian public universities stands point East Coast of
Malaysia. The aim of this study is to analyze the effects of
knowledge management on human capital toward organizational
innovation. The focus point of this study is on the management
member in the faculties of these three Malaysian Public Universities
in the East Coast state of Peninsular Malaysia. In this case,
respondents who agreed to further participate in the research will be
invited to a one-hour face-to-face semi-structured, in-depth interview.
As a result, the sample size for this study was 3 deans of Faculty of
Management. Lastly, this study tries to recommend the framework of
organizational innovation in Malaysian Public Universities.
Abstract: Recent concerns about the value of teaching cursive
handwriting in the classroom are based on the belief that cursive
handwriting or penmanship is an outdated and unnecessary skill in
today’s online world. The discussion of this issue begins with a
description of current initiatives to eliminate handwriting instruction
in schools. This is followed by a brief history of cursive writing
through the ages. Next considered is a description of its benefits as a
preliminary process for younger children as compared with
immediate instruction in keyboarding, particularly in the areas of
vision, cognition, motor skills and automatic fluency. Also
considered, is cursive’s companion, paper itself, and the impact of a
paperless, “screen and keyboard” environment. The discussion
concludes with a consideration of the unique contributions of cursive
and keyboarding as written forms of communication, along with their
respective surfaces, paper and screen. Finally, an assessment of the
practical utility of each skill is followed by an informal assessment of
what is lost and what remains as we move from a predominantly
paper and pen world of handwriting to texting and keyboarding in an
environment of screens.
Abstract: Nonstandard tests are necessary for analyses and
verification of new developed structural and technological solutions
with application of composite materials. One of the most critical
primary structural parts of a typical aerospace structure is T-joint.
This structural element is loaded mainly in shear, bending, peel and
tension. The paper is focused on the shear loading simulations. The
aim of the work is to obtain a representative uniform distribution of
shear loads along T-joint during the mechanical testing. A new
design of T-joint test procedure, numerical simulation and
optimization of representative boundary conditions are presented.
The different conditions and inaccuracies both in simulations and
experiments are discussed. The influence of different parameters on
stress and strain distributions is demonstrated on T-joint made of
CFRP (carbon fibre reinforced plastic). A special test rig designed by
VZLU (Aerospace Research and Test Establishment) for T-shear test
procedure is presented.
Abstract: In this paper the effect of wall waviness of side walls
in a two-dimensional wavy enclosure is numerically investigated.
Two vertical wavy walls and straight top wall are kept isothermal and
the bottom wall temperature is higher and spatially varying with
cosinusoidal temperature distribution. A computational code based on
Finite-volume approach is used to solve governing equations and
SIMPLE method is used for pressure velocity coupling. Test is
performed for several different numbers of undulations. The Prandtl
number was kept constant and the Ra number denotes that the flow is
laminar. Temperature and velocity fields are determined. Therefore,
according to the obtained results a correlation is proposed for average
Nusselt number as a function of number of side wall waves. The
results indicate that the Nusselt number is highly affected by number
of waves and increasing it decreases the wavy walls Nusselt number;
although the Nusselt number is not highly affected by surface
waviness when the number of undulations is below one.
Abstract: This paper presents a 4-DOF nonlinear model of a
cracked de Laval rotor-stator system derived based on Energy
Principles. The model has been used to simulate coupled torsionallateral
response of the faulty system with multiple parametric
excitations; rotor-stator-rub, a breathing transverse crack, eccentric
mass and an axial force. Nonlinearity of a “breathing” crack is
incorporated in the model using a simple hinge mechanism suitable
for a shallow crack. Response of the system while passing via its
critical speed with intermittent rotor-stator rub is analyzed. Effects of
eccentricity with phase and acceleration are investigated. Features of
crack, rub and eccentricity in vibration response are explored for
condition monitoring. The presence of a crack and rub are observable
in the power spectrum despite excitations by an axial force and rotor
unbalance. Obtained results are consistent with existing literature and
could be adopted into rotor condition monitoring strategies.
Abstract: The article discusses multimodal mobility in
contemporary societies as a main planning and organization issue in
the functioning of administrative bodies, a problem which really
exists in the space of contemporary cities in terms of shaping modern
transport systems. The article presents classification of available
resources and initiatives undertaken for developing multimodal
mobility. Solutions can be divided into three groups of measures –
physical measures in the form of changes of the transport network
infrastructure, organizational ones (including transport policy) and
information measures. The latter ones include in particular direct
support for people travelling in the transport network by providing
information about ways of using available means of transport. A
special measure contributing to this end is a trip planner. The article
compares several selected planners. It includes a short description of
the Green Travelling Project, which aims at developing a planner
supporting environmentally friendly solutions in terms of transport
network operation. The article summarizes preliminary findings of
the project.
Abstract: reliability-based methodology for the assessment
and evaluation of reinforced concrete (R/C) structural elements of
concrete structures is presented herein. The results of the reliability
analysis and assessment for R/C structural elements were verified by
the results obtained through deterministic methods. The outcomes of
the reliability-based analysis were compared against currently
adopted safety limits that are incorporated in the reliability indices
β’s, according to international standards and codes. The methodology
is based on probabilistic analysis using reliability concepts and
statistics of the main random variables that are relevant to the subject
matter, and for which they are to be used in the performance-function
equation(s) associated with the structural elements under study.
These methodology techniques can result in reliability index β, which
is commonly known as the reliability index or reliability measure
value that can be utilized to assess and evaluate the safety, human
risk, and functionality of the structural component. Also, these
methods can result in revised partial safety factor values for certain
target reliability indices that can be used for the purpose of
redesigning the R/C elements of the building and in which they could
assist in considering some other remedial actions to improve the
safety and functionality of the member.
Abstract: In this paper, design of solid-state battery/supercapacitor emulator based on dc-dc boost converter is described.
The emulator mimics charging behavior of any storage device based
on a predefined behavior set by the user. The device is operated by a
two-level control structure: high-level emulating controller and low-
level input voltage controller. Simulation and experimental results are
shown to demonstrate the emulator operation.
Abstract: In the culture of Thailand, the Yak serve as a mediated
icon representing strength, power, and mystical protection not only
for the Buddha, but for population of worshipers. Originating from
the forests of China, the Yak continues to stand guard at the gates of
Buddhist temples. The Yak represents Thai culture in the hearts of
Thai people. This paper presents a qualitative study regarding the
curious mix of media, culture, and religion that projects the Yak of
Thailand as a larger than life message throughout the political,
cultural, and religious spheres. The gate guardians, or gods as they
are sometimes called, appear throughout the religious temples of
Asian cultures. However, the Asian cultures demonstrate differences
in artistic renditions (or presentations) of such sentinels. Thailand
gate guards (the Yak) stand in front of many Buddhist temples, and
these iconic figures display unique features with varied symbolic
significance. The temple (or wat), plays a vital role in every
community; and, for many people, Thailand’s temples are the
country’s most endearing sights. The authors applied folknography as
a methodology to illustrate the importance of the Thai Yak in serving
as meaningful icons that transcend not only time, but the culture,
religion, and mass media. The Yak represents mythical, religious,
artistic, cultural, and militaristic significance for the Thai people.
Data collection included interviews, focus groups, and natural
observations. This paper summarizes the perceptions of the Thai
people concerning their gate sentries and the relationship,
communication, connection, and the enduring respect that Thai
people hold for their guardians of the gates.
Abstract: This paper is devoted to the study of a viscous
incompressible flow around a circular cylinder performing harmonic
oscillations, especially the steady streaming phenomenon. The
research methodology is based on the asymptotic explanation method
combined with the computational bifurcation analysis. The research
approach develops Schlichting and Wang decomposition method.
Present studies allow to identify several regimes of the secondary
streaming with different flow structures. The results of the research
are in good agreement with experimental and numerical simulation
data.
Abstract: Characterization of the engineering behavior of
unsaturated soil is dependent on the soil-water characteristic curve
(SWCC), a graphical representation of the relationship between water
content or degree of saturation and soil suction. A reasonable
description of the SWCC is thus important for the accurate prediction
of unsaturated soil parameters. The measurement procedures for
determining the SWCC, however, are difficult, expensive, and timeconsuming.
During the past few decades, researchers have laid a
major focus on developing empirical equations for predicting the
SWCC, with a large number of empirical models suggested. One of
the most crucial questions is how precisely existing equations can
represent the SWCC. As different models have different ranges of
capability, it is essential to evaluate the precision of the SWCC
models used for each particular soil type for better SWCC estimation.
It is expected that better estimation of SWCC would be achieved via
a thorough statistical analysis of its distribution within a particular
soil class. With this in view, a statistical analysis was conducted in
order to evaluate the reliability of the SWCC prediction models
against laboratory measurement. Optimization techniques were used
to obtain the best-fit of the model parameters in four forms of SWCC
equation, using laboratory data for relatively coarse-textured (i.e.,
sandy) soil. The four most prominent SWCCs were evaluated and
computed for each sample. The result shows that the Brooks and
Corey model is the most consistent in describing the SWCC for sand
soil type. The Brooks and Corey model prediction also exhibit
compatibility with samples ranging from low to high soil water
content in which subjected to the samples that evaluated in this study.
Abstract: Immunomodulators are substances that alter immune
system via dynamic regulation of messenger molecules. It can be
divided into immunostimulant and immunosuppressant. It can help to
increase immunity of people with a low immune system, and also can
help to normalize an overactive immune system. Aim of this study is
to investigate the effects of in vitro exposure to low and high doses of
several immunomodulators which include caffeine, kaloba and
quercetin on antigen-stimulated whole blood culture cytokine
production. Whole blood samples were taken from 5 healthy males
(age: 32 ± 12 years; weight: 75.7 ± 6.1 kg; BMI: 24.3 ± 1.5 kg/m2)
following an overnight fast with no vigorous activity during the
preceding 24 h. The whole blood was then stimulated with 50 μl of
100 x diluted Pediacel vaccine and low or high dose of
immunomodulators in the culture plate. After 20 h incubation (5%
CO2, 37°C), it was analysed using the Evidence Investigator to
determine the production of cytokines including IL-2, IL-4, IL-10,
IFN-γ, and IL-1α. Caffeine and quercetin showed a tendency towards
decrease cytokine production as the doses were increased. On the
other hand, an upward trend was evident with kaloba, where a high
dose of kaloba seemed to increase the cytokine production. In
conclusion, we found that caffeine and quercetin have potential as
immunosuppressant and kaloba as immunostimulant.
Abstract: In this paper, we present a comparative assessment of
Space Vector Pulse Width Modulation (SVPWM) and Model
Predictive Control (MPC) for two-level three phase (2L-3P) Voltage
Source Inverter (VSI). VSI with associated system is subjected to
both control techniques and the results are compared.
Matlab/Simulink was used to model, simulate and validate the
control schemes. Findings of this study show that MPC is superior to
SVPWM in terms of total harmonic distortion (THD) and
implementation.
Abstract: This study aimed at investigating whether the
functional brain networks constructed using the initial EEG (obtained
when patients first visited hospital) can be correlated with the
progression of cognitive decline calculated as the changes of
mini-mental state examination (MMSE) scores between the latest and
initial examinations. We integrated the time–frequency cross mutual
information (TFCMI) method to estimate the EEG functional
connectivity between cortical regions, and the network analysis based
on graph theory to investigate the organization of functional networks
in aMCI. Our finding suggested that higher integrated functional
network with sufficient connection strengths, dense connection
between local regions, and high network efficiency in processing
information at the initial stage may result in a better prognosis of the
subsequent cognitive functions for aMCI. In conclusion, the functional
connectivity can be a useful biomarker to assist in prediction of
cognitive declines in aMCI.
Abstract: The detection of environmental gases, 12CO2, 13CO2,
and CH4, using near-infrared semiconductor lasers with a short
laser path length is studied by means of wavelength-modulation
spectroscopy. The developed system is compact and has high
sensitivity enough to detect the absorption peaks of isotopic 13CO2
of a 3-% CO2 gas at 2 μm with a path length of 2.4 m, where
its peak size is two orders of magnitude smaller than that of the
ordinary 12CO2 peaks. In addition, the detection of 12CO2 peaks of
a 385-ppm (0.0385-%) CO2 gas in the air is made at 2 μm with a
path length of 1.4 m. Furthermore, in pursuing the detection of an
ancient environmental CH4 gas confined to a bubble in ice at the
polar regions, measurements of the absorption spectrum for a trace
gas of CH4 in a small area are attempted. For a 100-% CH4 gas
trapped in a ∼ 1 mm3 glass container, the absorption peaks of CH4
are obtained at 1.65 μm with a path length of 3 mm, and also the
gas pressure is extrapolated from the measured data.
Abstract: A wireless sensor network (WSN) is a collection of
sensor nodes organized into a cooperative network. These nodes
communicate through a wireless antenna. Reduction in physical size
and multiband operation is an important requirement of WSN
antenna. Fractal antenna is used for miniaturization and multiband
operation. The self-similar or self-affine and space filling property of
fractal geometry increases the effective electrical length of the
antenna, reduces the size and make them frequency independent. This
paper elaborates on Dual band fractal antenna with Coplanar
Waveguide (CPW) feed for WSN. The proposed antenna is designed
on a FR4 substrate with the dimension of 27mm x 28.5mm x 1.6mm,
resonates at 2.4GHz and 5.2GHz with a return loss less than -10dB.
The design and simulation process is carried out using IE3D
simulation software. The simulated and measured results are found in
good agreement.