Abstract: This paper describes the development of a boundary
fitted nested grid (BFNG) model to compute tsunami propagation of
2004 Indonesian tsunami in Southern Thailand coastal waters. We
develop a numerical model employing the shallow water nested
model and an orthogonal boundary fitted grid to investigate the
tsunami impact on the Southern Thailand due to the Indonesian
tsunami of 2004. Comparisons of water surface elevation obtained
from numerical simulations and field measurements are made.
Abstract: This paper is concerned with the single-item
continuous review inventory system in which demand is stochastic
and discrete. The budget consumed for purchasing the ordered items
is not restricted but it incurs extra cost when exceeding specific
value. The unit purchasing price depends on the quantity ordered
under the all-units discounts cost structure. In many actual systems,
the budget as a resource which is occupied by the purchased items is
limited and the system is able to confront the resource shortage by
charging more costs. Thus, considering the resource shortage costs as
a part of system costs, especially when the amount of resource
occupied by the purchased item is influenced by quantity discounts,
is well motivated by practical concerns. In this paper, an optimization
problem is formulated for finding the optimal (r, Q) policy, when the
system is influenced by the budget limitation and a discount pricing
simultaneously. Properties of the cost function are investigated and
then an algorithm based on a one-dimensional search procedure is
proposed for finding an optimal (r, Q) policy which minimizes the
expected system costs.
Abstract: Different terms of the Statistical Process Control (SPC)
has sketch in the fuzzy environment. However, Measurement System
Analysis (MSA), as a main branch of the SPC, is rarely investigated
in fuzzy area. This procedure assesses the suitability of the data to be
used in later stages or decisions of the SPC. Therefore, this research
focuses on some important measures of MSA and through a new
method introduces the measures in fuzzy environment. In this
method, which works based on Buckley approach, imprecision and
vagueness nature of the real world measurement are considered
simultaneously. To do so, fuzzy version of the gauge capability (Cg
and Cgk) are introduced. The method is also explained through
example clearly.
Abstract: The spindle system is one of the most important
components of machine tool. The dynamic properties of the spindle
affect the machining productivity and quality of the work pieces.
Thus, it is important and necessary to determine its dynamic
characteristics of spindles in the design and development in order to
avoid forced resonance. The finite element method (FEM) has been
adopted in order to obtain the dynamic behavior of spindle system.
For this reason, obtaining the Campbell diagrams and determining the
critical speeds are very useful to evaluate the spindle system
dynamics. The unbalance response of the system to the center of
mass unbalance at the cutting tool is also calculated to investigate the
dynamic behavior. In this paper, we used an ANSYS Parametric
Design Language (APDL) program which based on finite element
method has been implemented to make the full dynamic analysis and
evaluation of the results. Results show that the calculated critical
speeds are far from the operating speed range of the spindle, thus, the
spindle would not experience resonance, and the maximum
unbalance response at operating speed is still with acceptable limit.
ANSYS Parametric Design Language (APDL) can be used by spindle
designer as tools in order to increase the product quality, reducing
cost, and time consuming in the design and development stages.
Abstract: A flow column has been innovatively used in the
design of a new electrocoagulation reactor (ECR1) that will reduce
the temperature of water being treated; where the flow columns work
as a radiator for the water being treated. In order to investigate the
performance of ECR1 and compare it to that of traditional reactors;
600 mL water samples with an initial temperature of 350C were
pumped continuously through these reactors for 30 min at current
density of 1 mA/cm2. The temperature of water being treated was
measured at 5 minutes intervals over a 30 minutes period using a
thermometer. Additional experiments were commenced to investigate
the effects of initial temperature (15-350C), water conductivity (0.15
– 1.2 S) and current density (0.5 -3 mA/cm2) on the performance of
ECR1.
The results obtained demonstrated that the ECR1, at a current
density of 1 mA/cm2 and continuous flow model, reduced water
temperature from 350C to the vicinity of 280C during the first 15
minutes and kept the same level till the end of the treatment time.
While, the temperature increased from 28.1 to 29.80C and from 29.8
to 31.90C in the batch and the traditional continuous flow models
respectively. In term of initial temperature, ECR1 maintained the
temperature of water being treated within the range of 22 to 280C
without the need for external cooling system even when the initial
temperatures varied over a wide range (15 to 350C). The influent
water conductivity was found to be a significant variable that affect
the temperature. The desirable value of water conductivity is 0.6 S.
However, it was found that the water temperature increased rapidly
with a higher current density.
Abstract: File sharing in networks is generally achieved using
Peer-to-Peer (P2P) applications. Structured P2P approaches are
widely used in adhoc networks due to its distributed and scalability
features. Efficient mechanisms are required to handle the huge
amount of data distributed to all peers. The intrinsic characteristics of
P2P system makes for easier content distribution when compared to
client-server architecture. All the nodes in a P2P network act as both
client and server, thus, distributing data takes lesser time when
compared to the client-server method. CHORD protocol is a resource
routing based where nodes and data items are structured into a 1-
dimensional ring. The structured lookup algorithm of Chord is
advantageous for distributed P2P networking applications. However,
structured approach improves lookup performance in a high
bandwidth wired network it could contribute to unnecessary overhead
in overlay networks leading to degradation of network performance.
In this paper, the performance of existing CHORD protocol on
Wireless Mesh Network (WMN) when nodes are static and dynamic
is investigated.
Abstract: In the present study, the properties of Al-Al2O3
nanocomposite hollow sphere structures were investigated. For this
reason, the Al-based nanocomposite hollow spheres with different
amounts of nano-alumina reinforcement (0-10wt %) and different
ratio of thickness to diameter (t/D: 0.06-0.3) were prepared via a
powder metallurgy method. Then, the effect of mentioned parameters
was studied on physical and quasi static mechanical properties of
their related prepared structures (open/closed cell) such as density,
hardness, strength, and energy absorption. It was found that, as the
t/D ratio increases the relative density, compressive strength and
energy absorption increase. The highest values of strength and energy
absorption were obtained from the specimen with 5 wt. % of
nanoparticle reinforcement, t/D of 0.3 (t=1 mm, D=400μm) as 22.88
MPa and 13.24 MJ/m3, respectively. The moderate specific strength
of prepared composites in the present study showed the good
consistency with the properties of others low carbon steel composite
with similar structure.
Abstract: Method of combined teaching laws of classical
mechanics and hydrostatics in non-inertial reference frames for
undergraduate students is proposed. Pressure distribution in a liquid
(or gas) moving with acceleration is considered. Combined effect of
hydrostatic force and force of inertia on a body immersed in a liquid
can lead to paradoxical results, in a motion of pendulum in particular.
The body motion under Stokes force influence and forces in rotating
reference frames are investigated as well. Problems and difficulties in
student perceptions are analyzed.
Abstract: Propagation of arbitrary amplitude nonlinear Alfven
waves has been investigated in low but finite β electron-positron-ion
plasma including full ion dynamics. Using Sagdeev pseudopotential
method an energy integral equation has been derived. The Sagdeev
potential has been calculated for different plasma parameters and it
has been shown that inclusion of ion parallel motion along the
magnetic field changes the nature of slow shear Alfven wave solitons
from dip type to hump type. The effects of positron concentration,
plasma-β and obliqueness of the wave propagation on the solitary
wave structure have also been examined.
Abstract: The use of titanium fluoride and iron fluoride
(TiF3/FeF3) catalysts in combination with polutetrafluoroethylene
(PTFE) in plain zinc- dialkyldithiophosphate (ZDDP) oil is important
for the study of engine tribocomponents and is increasingly a strategy
to improve the formation of tribofilm and provide low friction and
excellent wear protection in reduced phosphorus plain ZDDP oil. The
influence of surface roughness and the concentration of
TiF3/FeF3/PTFE were investigated using bearing steel samples
dipped in lubricant solution at 100°C for two different heating time
durations. This paper addresses the effects of water drop contact
angle using different surface; finishes after treating them with
different lubricant combination. The calculated water drop contact
angles were analyzed using Design of Experiment software (DOE)
and it was determined that a 0.05 μm Ra surface roughness would
provide an excellent TiF3/FeF3/PTFE coating for antiwear resistance
as reflected in the Scanning electron microscopy (SEM) images and
the tribological testing under extreme pressure conditions. Both
friction and wear performance depend greatly on the PTFE/and
catalysts in plain ZDDP oil with 0.05 % phosphorous and on the
surface finish of bearing steel. The friction and wear reducing effects,
which was observed in the tribological tests, indicated a better micro
lubrication effect of the 0.05 μm Ra surface roughness treated at
100°C for 24 hours when compared to the 0.1 μm Ra surface
roughness with the same treatment.
Abstract: Background: Muscle Energy Techniques (MET) have
been widely used by manual therapists over the past years, but still
limited research validated its use and there was limited evidence to
substantiate the theories used to explain its effects. Objective: To
investigate the effect of Muscle Energy Technique (MET) on anterior
pelvic tilt in patients with lumbar spondylosis. Design: Randomized
controlled trial. Subjects: Thirty patients with anterior pelvic tilt from
both sexes were involved, aged between 35 to 50 years old and they
were divided into MET and control groups with 15 patients in each.
Methods: All patients received 3sessions/week for 4 weeks where the
study group received MET, Ultrasound and Infrared, and the control
group received U.S and I.R only. Pelvic angle was measured by
palpation meter, pain severity by the visual analogue scale and
functional disabilities by the Oswestry disability index. Results: Both
groups showed significant improvement in all measured variables.
The MET group was significantly better than the control group in
pelvic angle, pain severity, and functional disability as p-value were
(0.001, 0.0001, 0.0001) respectively. Conclusion and implication: the
study group fulfilled greater improvement in all measured variables
than the control group which implies that application of MET in
combination with U.S and I.R were more effective in improving
pelvic tilting angle, pain severity and functional disabilities than
using electrotherapy only.
Abstract: This study makes an integrated investigation on how
life satisfaction is associated with the Korean game users'
psychological variables (self-esteem, game and life self- efficacy),
social variables (bonding and bridging social capital), and
demographic variables (age, gender). The data used for the empirical
analysis came from a representative sample survey conducted in South
Korea. Results show that self-esteem and game efficacy were an
important antecedent to the degree of users’ life satisfaction. Both
bonding social capital and bridging social capital enhance the level of
the users’ life satisfaction. The importance of perspectives as well as
their implications for the game users and further associated research is
explored.
Abstract: A lower consumption of thermal energy will
contribute not only to a reduction in the running costs, but also in the
reduction of pollutant emissions that contribute to the greenhouse
effect. Cogeneration or CHP (Combined Heat and Power) is the
system that produces power and usable heat simultaneously by
decreasing the pollutant emissions and increasing the efficiency.
Combined production of mechanical or electrical and thermal energy
using a simple energy source, such as oil, coal, natural or liquefied
gas, biomass or the sun; affords remarkable energy savings and
frequently makes it possible to operate with greater efficiency when
compared to a system producing heat and power separately. This
study aims to bring out the contributions of cogeneration systems to
the environment and sustainability by saving the energy and reducing
the emissions. In this way we made a comprehensive investigation in
the literature by focusing on the environmental aspects of the
cogeneration systems. In the light of these studies we reached that,
cogeneration systems must be consider in sustainability and their
benefits on protecting the ecology must be investigated.
Abstract: A novel chromium-free protective coating films based
on a zeolite coating was growing onto a FeCrAlloy metal using in –
situ hydrothermal method. The zeolite film was obtained using in-situ
crystallization process that is capable of coating large surfaces with
complex shape and in confined spaces has been developed. The
zeolite coating offers an advantage of a high mechanical stability and
thermal stability. The physicochemical properties were investigated
using X-ray diffraction (XRD), Electron Microscopy (SEM), Energy
Dispersive X–ray Analysis (EDX) and Thermogravimetric Analysis
(TGA). The transition from oxide-on-alloy wires to hydrothermally
synthesised uniformly zeolite coated surfaces was followed using
SEM and XRD. In addition, the robustness of the prepared coating
was confirmed by subjecting these to thermal cycling (ambient to
550oC).
Abstract: Grains, including oats (Avena sativa L.), have been
recognized functional foods, because provide beneficial effect on the
health of the consumer and decrease the risk of various diseases. Oats
are good source of soluble fibre, essential amino acids, unsaturated
fatty acids, vitamins and minerals. Oat breeders have developed oat
varieties and improved yielding ability potential of oat varieties.
Therefore, the aim of investigation was to analyze the composition of
perspective oat varieties and breeding lines grains grown in different
conditions and evaluate functional properties. In the studied samples
content of protein, starch, β-glucans, total dietetic fibre, composition
of amino acids and vitamin E were determined. The results of
analysis showed that protein content depending of varieties ranged
9.70% to 17.30% total dietary fibre 13.66 g100g-1 to 30.17 g100g-1,
content of β-glucans 2.7 g100g-1 to 3.5 g100g-1, amount of
vitamin E (α-tocopherol) determined from 4 mgkg-1 to 9.9 mgkg-1.
The sums of essential amino acids in oat grain samples were
determined from 31.63 gkg-1 to 54.90 gkg-1. It is concluded that
amino acids composition of husked and naked oats grown in organic
or conventional conditions is close to optimal for human health.
Abstract: The aim of the present study is to investigate
consumers' determinants of intention toward the adoption of Smart
Grid solutions and technologies. Ajzen's Theory of Planned
Behaviour (TPB) model is applied and tested to explain the formation
of such adoption intention. An exogenous variable, taking into
account the resistance to change of individuals, was added to the
basic model. The elicitation study allowed obtaining salient modal
beliefs, which were used, with the support of literature, to design the
questionnaire. After the screening phase, data collected from the
main survey were analysed for evaluating measurement model's
reliability and validity. Consistent with the theory, the results of
structural equation analysis revealed that attitude, subjective norm,
and perceived behavioural control positively, which affected the
adoption intention. Specifically, the variable with the highest estimate
loading factor was found to be the perceived behavioural control,
and, the most important belief related to each construct was
determined (e.g., energy saving was observed to be the most
significant belief linked with attitude). Further investigation indicated
that the added exogenous variable has a negative influence on
intention; this finding confirmed partially the hypothesis, since this
influence was indirect: such relationship was mediated by attitude.
Implications and suggestions for future research are discussed.
Abstract: Chalcopyrite (CuFeS2) is the most common primary
mineral used for the commercial production of copper. The low
dissolution efficiency of chalcopyrite in sulfate media has prevented
an efficient industrial leaching of this mineral in sulfate media. Ferric
ions, bacteria, oxygen and other oxidants have been used as oxidizing
agents in the leaching of chalcopyrite in sulfate and chloride media
under atmospheric or pressure leaching conditions. Two leaching
methods were studied to evaluate chalcopyrite (CuFeS2) dissolution
in acid media. First, the conventional oxidative acid leaching method
was carried out using sulfuric acid (H2SO4) and potassium
dichromate (K2Cr2O7) as oxidant at atmospheric pressure. Second,
microwave-assisted acid leaching was performed using the
microwave accelerated reaction system (MARS) for same reaction
media. Parameters affecting the copper extraction such as leaching
time, leaching temperature, concentration of H2SO4 and
concentration of K2Cr2O7 were investigated. The results of
conventional acid leaching experiments were compared to the
microwave leaching method. It was found that the copper extraction
obtained under high temperature and high concentrations of oxidant
with microwave leaching is higher than those obtained
conventionally. 81% copper extraction was obtained by the
conventional oxidative acid leaching method in 180 min, with the
concentration of 0.3 mol/L K2Cr2O7 in 0.5M H2SO4 at 50 ºC, while
93.5% copper extraction was obtained in 60 min with microwave
leaching method under same conditions.
Abstract: In this paper, we provided a literature survey on the
artificial stock problem (ASM). The paper began by exploring the
complexity of the stock market and the needs for ASM. ASM
aims to investigate the link between individual behaviors (micro
level) and financial market dynamics (macro level). The variety of
patterns at the macro level is a function of the AFM complexity. The
financial market system is a complex system where the relationship
between the micro and macro level cannot be captured analytically.
Computational approaches, such as simulation, are expected to
comprehend this connection. Agent-based simulation is a simulation
technique commonly used to build AFMs. The paper proceeds by
discussing the components of the ASM. We consider the roles
of behavioral finance (BF) alongside the traditionally risk-averse
assumption in the construction of agent’s attributes. Also, the
influence of social networks in the developing of agents interactions is
addressed. Network topologies such as a small world, distance-based,
and scale-free networks may be utilized to outline economic
collaborations. In addition, the primary methods for developing
agents learning and adaptive abilities have been summarized.
These incorporated approach such as Genetic Algorithm, Genetic
Programming, Artificial neural network and Reinforcement Learning.
In addition, the most common statistical properties (the stylized facts)
of stock that are used for calibration and validation of ASM are
discussed. Besides, we have reviewed the major related previous
studies and categorize the utilized approaches as a part of these
studies. Finally, research directions and potential research questions
are argued. The research directions of ASM may focus on the macro
level by analyzing the market dynamic or on the micro level by
investigating the wealth distributions of the agents.
Abstract: Nowadays, several research studies point up that an
active lifestyle is essential for physical and mental health benefits.
Mobile phones have greatly influenced people’s habits and attitudes
also in the way they exercise. Our research work is mainly focused on
investigating how to exploit mobile technologies to favour people’s
exertion experience. To this end, we developed an exertion framework
users can exploit through a real world mobile application, called
EverywhereSport Run (EWRun), designed to act as a virtual personal
trainer to support runners during their trainings. In this work, inspired
by both previous findings in the field of interaction design for people
with visual impairments, feedback gathered from real users of our
framework, and positive results obtained from two experimentations,
we present some new interaction facilities we designed to enhance
the interaction experience during a training. The positive obtained
results helped us to derive some interaction design recommendations
we believe will be a valid support for designers of future mobile
systems conceived to be used in circumstances where there are limited
possibilities of interaction.
Abstract: This paper presents modeling and simulation of
flexible robot in an underwater environment. The underwater
environment completely contrasts with ground or space environment.
The robot in an underwater situation is subjected to various dynamic
forces like buoyancy forces, hydrostatic and hydrodynamic forces.
The underwater robot is modeled as Rayleigh beam. The developed
model further allows estimating the deflection of tip in two
directions. The complete dynamics of the underwater robot is
analyzed, which is the main focus of this investigation. The control of
robot trajectory is not discussed in this paper. Simulation is
performed using Symbol Shakti software.