Abstract: Problem of food preservation is extremely important
for mankind. Viscous damage ("illness") of bread results from
development of Bacillus spp. bacteria. High temperature resistant
spores of this microorganism are steady against 120°C) and remain in
bread during pastries, potentially causing spoilage of the final
product. Scientists are interested in further characterization of bread
spoiling Bacillus spp. species. Our aim was to find weather yeast
Saccharomyces cerevisiae strains that are able to produce natural
antimicrobial killer factor can preserve bread illness. By diffusion
method, we showed yeast antagonistic activity against spore-forming
bacteria. Experimental technological parameters were the same as for
bakers' yeasts production on the industrial scale. Risograph test
during dough fermentation demonstrated gas production. The major
finding of the study was a clear indication of the presence of killer
yeast strain antagonistic activity against rope in bread causing
bacteria. After demonstrating antagonistic effect of S. cerevisiae on
bacteria using solid nutrient medium, we tested baked bread under
provocative conditions. We also measured formation of carbon
dioxide in the dough, dough-making duration and quality of the final
products, when using different strains of S. cerevisiae. It is
determined that the use of yeast S. cerevisiae RCAM 01730 killer
strain inhibits appearance of rope in bread. Thus, natural yeast
antimicrobial killer toxin, produced by some S. cerevisiae strains is
an anti-rope in bread protector.
Abstract: The present study is based on the three-dimensional digital analysis by the finite elements method of the mechanical loading effect on the delamination of unidirectional and multidirectional stratified composites. The aim of this work is the determination of the release energy rate G in mode I and the Von Mises equivalent constraint distribution along the damaged area under the influence of several parameters such as the applied load and the delamination size. The results obtained in this study show that the unidirectional composite laminates have better mechanical resistance one the loading line than the multidirectional composite laminates.
Abstract: To focus on the vibration mode of a cone loudspeaker,
which acts as an electroacoustic transducer, excitation experiments
were performed using two types of loudspeaker units: one employing
an impulse hammer and the other a sweep signal. The on-axis sound
pressure frequency properties of the loudspeaker were evaluated, and
the characteristic properties of the loudspeakers were successfully
determined in both excitation experiments. Moreover, under
conditions identical to the experiment conditions, a coupled analysis of
the vibration-acoustics of the cone loudspeaker was performed using
an acoustic analysis software program that considers the impact of
damping caused by air viscosity. The result of sound pressure
frequency properties with the numerical analysis are the most closely
match that measured in the excitation experiments over a wide range
of frequency bands.
Abstract: 10 clinically healthy hemal nodes were collected from male bulls aged 2-3 years. Light microscopy revealed a capsule of connective tissue consisted mainly of collagen fiber surrounding hemal node, numerous erythrocytes were found in wide subcapsular sinus under the capsule. The parenchyma of the hemal node was divided into cortex and medulla. Diffused lymphocytes, and lymphoid follicles, having germinal centers were the main components of the cortex, while in the medulla there was wide medullary sinus, diffused lymphocytes and few lymphoid nodules. The area occupied with lymph nodules was larger than that occupied with non-nodular structure of lymphoid cords and blood sinusoids. Electron microscopy revealed the cellular components of hemal node including elements of circulating erythrocytes intermingled with lymphocytes, plasma cells, mast cells, reticular cells, macrophages, megakaryocytes and endothelial cells lining the blood sinuses. The lymphocytes were somewhat triangular in shape with cytoplasmic processes extending between adjacent erythrocytes. Nuclei were triangular to oval in shape, lightly stained with clear nuclear membrane indentation and clear nucleoli. The reticular cells were elongated in shape with cytoplasmic processes extending between adjacent lymphocytes, rough endoplasmic reticulum, ribosomes and few lysosomes were seen in their cytoplasm. Nucleus was elongated in shape with less condensed chromatin. Plasma cells were oval to irregular in shape with numerous dilated rough endoplasmic reticulum containing electron lucent material occupying the whole cytoplasm and few mitochondria were found. Nuclei were centrally located and oval in shape with heterochromatin emarginated and often clumped near the nuclear membrane. Occasionally megakaryocytes and mast cells were seen among lymphocytes. Megakaryocytes had multilobulated nucleus and free ribosomes often appearing as small aggregates in their cytoplasm, while mast cell had their characteristic electron dense granule in the cytoplasm, few electron lucent granules were found also, we conclude that, the main function of the hemal node of cattle is proliferation of lymphocytes. No role for plasma cell in erythrophagocytosis could be suggested.
Abstract: Copreneurship is a term used to describe the business
pattern of operations run by married couples who share commitment,
goals, and responsibilities in handling a business. Research conducted
overseas showed that copreneurship business activities grew quickly
and played a role in elevating families’ and nations’ socio-economic
standards. In Malaysia, copreneurship has long been cultivated by
spouses. Thus, this study aimed to explore the factors that motivate
married partners to start a copreneurship business, and who is the
dominant partner in the management of this business. The study
participants are four entrepreneurial couples who are SME business
operators selected through purposive sampling. In-depth interviews
and direct observation were used as methods of measurement for
triangulation of qualitative data in this study. The findings of the
interviews were administered using NVivo 8.0 software. The result
shows that freedom is a key factor that drives entrepreneurs to set up
copreneurship businesses, and that the husband dominates the
management aspects of the business. The study gives an overview of
the parties involved in entrepreneurship to provide understanding of
the copreneurship concept as it is practiced. This study provides
academic value by creating understanding of the importance of a
harmonious family institution specifically for forming entrepreneurs
in the familial environment in Malaysia.
Abstract: Sun tracking systems are the systems following the sun ray by a right angle or by predetermined certain angle. In this study, we used theoretical trajectory of sun for latitude of central Anatolia in Turkey. A two degree of freedom spherical mechanism was designed to have a large workspace able to follow the sun's theoretical motion by the right angle during the whole year. An inverse kinematic analysis was generated to find the positions of mechanism links for the predicted trajectory. Force and torque analysis were shown for the first day of the year.
Abstract: The material selection problem is concerned with the
determination of the right material for a certain product to optimize
certain performance indices in that product such as mass, energy
density, and power-to-weight ratio. This paper is concerned about
optimizing the selection of the manufacturing process along with the
material used in the product under performance indices and
availability constraints. In this paper, the material selection problem
is formulated using binary programming and solved by genetic
algorithm. The objective function of the model is to minimize the
total manufacturing cost under performance indices and material and
manufacturing process availability constraints.
Abstract: Hydrologic models are increasingly used as tools to
predict stormwater quantity and quality from urban catchments.
However, due to a range of practical issues, most models produce
gross errors in simulating complex hydraulic and hydrologic systems.
Difficulty in finding a robust approach for model calibration is one of
the main issues. Though automatic calibration techniques are
available, they are rarely used in common commercial hydraulic and
hydrologic modelling software e.g. MIKE URBAN. This is partly
due to the need for a large number of parameters and large datasets in
the calibration process. To overcome this practical issue, a
framework for automatic calibration of a hydrologic model was
developed in R platform and presented in this paper. The model was
developed based on the time-area conceptualization. Four calibration
parameters, including initial loss, reduction factor, time of
concentration and time-lag were considered as the primary set of
parameters. Using these parameters, automatic calibration was
performed using Approximate Bayesian Computation (ABC). ABC is
a simulation-based technique for performing Bayesian inference
when the likelihood is intractable or computationally expensive to
compute. To test the performance and usefulness, the technique was
used to simulate three small catchments in Gold Coast. For
comparison, simulation outcomes from the same three catchments
using commercial modelling software, MIKE URBAN were used.
The graphical comparison shows strong agreement of MIKE URBAN
result within the upper and lower 95% credible intervals of posterior
predictions as obtained via ABC. Statistical validation for posterior
predictions of runoff result using coefficient of determination (CD),
root mean square error (RMSE) and maximum error (ME) was found
reasonable for three study catchments. The main benefit of using
ABC over MIKE URBAN is that ABC provides a posterior
distribution for runoff flow prediction, and therefore associated
uncertainty in predictions can be obtained. In contrast, MIKE
URBAN just provides a point estimate. Based on the results of the
analysis, it appears as though ABC the developed framework
performs well for automatic calibration.
Abstract: An experiment to verify the relationships between
physiological indexes of an e-learner and the presence or absence of an
operation during e-learning is described. Electroencephalogram
(EEG), hemoencephalography (HEG), skin conductance (SC), and
blood volume pulse (BVP) values were measured while participants
performed experimental learning tasks. The results show that there are
significant differences between the SC values when reading with
clicking on learning materials and the SC values when reading without
clicking, and between the HEG ratio when reading (with and without
clicking) and the HEG ratio when resting for four of five participants.
We conclude that the SC signals can be used to estimate whether or not
a learner is performing an active task and that the HEG ratios can be
used to estimate whether a learner is learning.
Abstract: Liquid storage tanks have become widespread during the recent decades due to their extensive usage. Analysis of liquid containing tanks is known to be complex due to hydrodynamic force exerted on tank which makes the analysis a complex one. The objective of this research is to carry out analysis of liquid domain along with structural interaction for various geometries of circular tanks considering seismic effects. An attempt has been made to determine hydrodynamic pressure distribution on the tank wall considering impulsive and convective components of liquid mass. To get a better picture, a comparative study of Draft IS 1893 Part 2, ACI 350.3 and Eurocode 8 for Circular Shaped Tank has been performed. Further, the differences in the magnitude of shear and moment at base as obtained from static (IS 3370 IV) and dynamic (Draft IS 1892 Part 2) analysis of ground supported circular tank highlight the need for us to mature from the old code to a newer code, which is more accurate and reliable.
Abstract: Electric field is an important fundamental concept in
electrostatics. In high-school, generally Thai students have already
learned about definition of electric field, electric field due to a point
charge, and superposition of electric fields due to multiple-point
charges. Those are the prerequisite basic knowledge students holding
before entrancing universities. In the first-year university level,
students will be quickly revised those basic knowledge and will be
then introduced to a more complicated topic—electric field due to
continuous charged distributions. We initially found that our
freshman students, who were from the Faculty of Science and
enrolled in the introductory physic course (SCPY 158), often
seriously struggled with the basic physics concepts—superposition of
electric fields and inverse square law and mathematics being relevant
to this topic. These also then resulted on students’ understanding of
advanced topics within the course such as Gauss's law, electric
potential difference, and capacitance. Therefore, it is very important
to determine students' understanding of electric field due to
continuous charged distributions. The open-ended question about
sketching net electric field vectors from a uniformly charged
insulating rod was administered to 260 freshman science students as
pre- and post-tests. All of their responses were analyzed and
classified into five levels of understandings. To get deep
understanding of each level, 30 students were interviewed toward
their individual responses. The pre-test result found was that about
90% of students had incorrect understanding. Even after completing
the lectures, there were only 26.5% of them could provide correct
responses. Up to 50% had confusions and irrelevant ideas. The result
implies that teaching methods in Thai high schools may be
problematic. In addition for our benefit, these students’ alternative
conceptions identified could be used as a guideline for developing the
instructional method currently used in the course especially for
teaching electrostatics.
Abstract: The tribological test with Pin-On-Disc configuration
measures friction and wear properties in dry or lubricated sliding
surfaces of a variety of materials and coatings. Polymeric matrix
composites loaded with mineral filler were used, 1%, 3%, 10%, 30%,
and 50% mass percentage of filler, to reduce the material cost by
using mineral tailings. Using a pin-on-disc tribometer to quantify
coefficient of friction and wear resistance of the specimens. The
parameters known to performing the test were 300 rpm rotation,
normal load of 16N and duration of 33.5 minutes. The composite
with 10% mineral filler performed better, considering that the wear
resistance was good when compared to the other compositions and an
average low coefficient of friction, in the order of μ ≤ 0.15.
Abstract: Microstructure and fabric of soils play an important
role on structural properties e.g. stiffness and strength of compacted
earthwork. Traditional quality control monitoring based on moisturedensity
tests neither reflects the variability of soil microstructure nor
provides a direct assessment of structural property, which is the
ultimate objective of the earthwork quality control. Since stiffness
and strength are sensitive to soil microstructure and fabric, any
independent test methods that provide simple, rapid, and direct
measurement of stiffness and strength are anticipated to provide an
effective assessment of compacted earthen materials’ uniformity. In
this study, the soil stiffness gauge (SSG) and the dynamic cone
penetrometer (DCP) were respectively utilized to measure and
monitor the stiffness and strength in companion with traditional
moisture-density measurements of various earthen materials used in
Thailand road construction projects. The practical earthwork quality
control criteria are presented herein in order to assure proper
earthwork quality control and uniform structural property of
compacted earthworks.
Abstract: HMS Industrial Networks AB has been recognized as
one of the most innovative companies in the industrial
communication industry worldwide. The creation of their Anybus
innovation during the 1990s contributed considerably to the
company’s success. From inception, HMS’ employees were
innovating for the purpose of creating new business (the creation
phase). After the Anybus innovation, they began the process of
internationalization (the commercialization phase), which in turn led
them to concentrate on cost reduction, product quality, delivery
precision, operational efficiency, and increasing growth (the growth
phase). As a result of this transformation, performing new radical
innovations have become more complicated. The purpose of our research was to explore the dynamics of
innovation at HMS from the aspect of key actors, activities, and
events, over the three phases, in order to understand what led to the
creation of their Anybus innovation, and why it has become
increasingly challenging for HMS to create new radical innovations
for the future. Our research methodology was based on a longitudinal,
retrospective study from the inception of HMS in 1988 to 2014, a
single case study inspired by the grounded theory approach. We
conducted 47 interviews and collected 1 024 historical documents for
our research. Our analysis has revealed that HMS’ success in creating the
Anybus, and developing a successful business around the innovation,
was based on three main capabilities – cultivating customer relations
on different managerial and organizational levels, inspiring business
relations, and balancing complementary human assets for the purpose
of business creation. The success of HMS has turned the management’s attention away
from past activities of key actors, of their behavior, and how they
influenced and stimulated the creation of radical innovations.
Nowadays, they are rhetorically focusing on creativity and
innovation. All the while, their real actions put emphasis on growth,
cost reduction, product quality, delivery precision, operational
efficiency, and moneymaking. In the process of becoming an
international company, HMS gradually refocused. In so doing they
became profitable and successful, but they also forgot what made
them innovative in the first place. Fortunately, HMS’ management
has come to realize that this is the case and they are now in search of
recapturing innovation once again. Our analysis indicates that HMS’ management is facing several
barriers to innovation related path dependency and other lock-in
phenomena. HMS’ management has been captured, trapped in their
mindset and actions, by the success of the past. But now their future has to be secured, and they have come to realize that moneymaking is
not everything. In recent years, HMS’ management have begun to
search for innovation once more, in order to recapture their past
capabilities for creating radical innovations. In order to unlock their
managerial perceptions of customer needs and their counter-innovation
driven activities and events, to utilize the full potential of
their employees and capture the innovation opportunity for the future.
Abstract: The cumulative costs for O&M may represent as
much as 65%-90% of the turbine's investment cost. Nowadays the
cost effectiveness concept becomes a decision-making and
technology evaluation metric. The cost of energy metric accounts for
the effect replacement cost and unscheduled maintenance cost
parameters. One key of the proposed approach is the idea of
maintaining the WTs which can be captured via use of a finite state
Markov chain. Such a model can be embedded within a probabilistic
operation and maintenance simulation reflecting the action to be
done. In this paper, an approach of estimating the cost of O&M is
presented. The finite state Markov model is used for decision
problems with number of determined periods (life cycle) to predict
the cost according to various options of maintenance.
Abstract: This paper discusses the intake of combining multi-criteria
decision analysis (MCDA) with OLAP systems, to generate
an integrated analysis process dealing with complex multi-criteria
decision-making situations. In this context, a multi-agent modeling is
presented for decision support systems by combining multi-criteria
decision analysis (MCDA) with OLAP systems. The proposed
modeling which consists in performing the multi-agent system
(MAS) architecture, procedure and protocol of the negotiation model
is elaborated as a decision support tool for complex decision-making
environments. Our objective is to take advantage from the multi-agent
system which distributes resources and computational
capabilities across interconnected agents, and provide a problem
modeling in terms of autonomous interacting component-agents.
Thus, the identification and evaluation of criteria as well as the
evaluation and ranking of alternatives in a decision support situation
will be performed by organizing tasks and user preferences between
different agents in order to reach the right decision. At the end, an
illustrative example is conducted to demonstrate the function and
effectiveness of our MAS modeling.
Abstract: In this study, thermal fatigue properties of 400 series
ferritic stainless steels have been evaluated in the temperature ranges
of 200-800oC and 200-900oC. Systematic methods for control of
temperatures within the predetermined range and measurement of load
applied to specimens as a function of temperature during thermal
cycles have been established. Thermal fatigue tests were conducted
under fully constrained condition, where both ends of specimens were
completely fixed. It has been revealed that load relaxation behavior at
the temperatures of thermal cycle was closely related with the thermal
fatigue property. Thermal fatigue resistance of 430J1L stainless steel
is found to be superior to the other steels.
Abstract: Recently developed cooperative diversity scheme
enables a terminal to get transmit diversity through the support of other
terminals. However, most of the introduced cooperative schemes have
a common fault of decreased transmission rate because the destination
should receive the decodable compositions of symbols from the source
and the relay. In order to achieve high data rate, we propose a
cooperative scheme that employs hierarchical modulation. This
scheme is free from the rate loss and allows seamless cooperative
communication.
Abstract: This paper investigates the effects of breaks in bonds,
breaks in the earthing system and breaks in earth wire on the rise of
the earth potential (EPR) in a substation and at the transmission tower
bases using various models of an L6 tower. Different approaches
were adopted to examine the integrity of the earthing system and the
terminal towers. These effects were investigated to see the associated
difference in the EPR magnitudes with respect to a healthy system at
various locations. Comparisons of the computed EPR magnitudes
were then made between the healthy and unhealthy system to detect
any difference. The studies were conducted at power frequency for a
uniform soil with different soil resistivities. It was found that full
breaks in the double bond of the terminal towers increase the EPR
significantly at the fault location, while they reduce EPR at the
terminal tower bases. A fault on the isolated section of the grid can
result in EPR values up to 8 times of those on a healthy system at
higher soil resistivities, provided that the extended earthing system
stays connected to the grid.
Abstract: Interaction between mixing and crystallization is often
ignored despite the fact that it affects almost every aspect of the
operation including nucleation, growth, and maintenance of the
crystal slurry. This is especially pronounced in multiple impeller
systems where flow complexity is increased. By choosing proper
mixing parameters, what closely depends on the knowledge of the
hydrodynamics in a mixing vessel, the process of batch cooling
crystallization may considerably be improved. The values that render
useful information when making this choice are mixing time and
power consumption. The predominant motivation for this work was
to investigate the extent to which radial dual impeller configuration
influences mixing time, power consumption and consequently the
values of metastable zone width and nucleation rate. In this research,
crystallization of borax was conducted in a 15 dm3 baffled batch
cooling crystallizer with an aspect ratio (H/T) of 1.3. Mixing was
performed using two straight blade turbines (4-SBT) mounted on the
same shaft that generated radial fluid flow. Experiments were
conducted at different values of N/NJS ratio (impeller speed/
minimum impeller speed for complete suspension), D/T ratio
(impeller diameter/crystallizer diameter), c/D ratio (lower impeller
off-bottom clearance/impeller diameter), and s/D ratio (spacing
between impellers/impeller diameter). Mother liquor was saturated at
30°C and was cooled at the rate of 6°C/h. Its concentration was
monitored in line by Na-ion selective electrode. From the values of
supersaturation that was monitored continuously over process time, it
was possible to determine the metastable zone width and
subsequently the nucleation rate using the Mersmann’s nucleation
criterion. For all applied dual impeller configurations, the mixing
time was determined by potentiometric method using a pulse
technique, while the power consumption was determined using a
torque meter produced by Himmelstein & Co. Results obtained in
this investigation show that dual impeller configuration significantly
influences the values of mixing time, power consumption as well as
the metastable zone width and nucleation rate. A special attention
should be addressed to the impeller spacing considering the flow
interaction that could be more or less pronounced depending on the
spacing value.