Abstract: Historic religious buildings located in seismic areas
have developed different failure mechanisms. Simulation of failure
modes is done with computer programs through a nonlinear dynamic
analysis or simplified using the method of failure blocks. Currently
there are simulation methodologies of failure modes based on the
failure rigid blocks method only for Roman Catholic churches type.
Due to differences of shape in plan, elevation and construction
systems between Orthodox churches and Catholic churches, for the
first time there were initiated researches in the development of this
simulation methodology for Orthodox churches. In this article are
presented the first results from the researches. The theoretical results
were compared with real failure modes recorded at an Orthodox
church from Banat region, severely damaged by earthquakes in
1991. Simulated seismic response, using a computer program based
on finite element method was confirmed by cracks after earthquakes.
The consolidation of the church was made according to these
theoretical results, realizing a rigid floor connecting all the failure
blocks.
Abstract: This paper presents the experimental results of silicone rubber outdoor polymer insulators in salt fog ageing test based on IEC 61109. Specimens made ofHTV silicone rubber with ATH content having three different configurations, straight shedsalternated sheds, and incline and alternate sheds, were tested continuously 1000 hrs.in artificial salt fog chamber. Contamination level, reduction of hydrophobicity and hardness measurement were used as physical damaged inspection techniques to evaluate degree of surface deterioration. In addition, chemical changing of tested specimen surface was evaluated by ATR-FTIRto confirm physical damaged inspection. After 1000 hrs.of salt fog test, differences in degree of surface deterioration were observed on all tested specimens. Physical damaged inspection and chemical analysis results confirmed the experimental results as well.
Abstract: Energy consumption is an important design issue for
Mobile Subscriber Station (MSS) in the standard IEEE 802.16e.
Because mobility of MSS implies that energy saving becomes an
issue so that lifetime of MSS can be extended before re-charging.
Also, the mechanism in efficiently managing the limited energy is
becoming very significant since a MSS is generally energized by
battery. For these, sleep mode operation is recently specified in the
MAC (Medium Access Control) protocol. In order to reduce the
energy consumption, we focus on the sleep-mode and wake-mode of
the MAC layer, which are included in the IEEE 802.16 standards [1-
2].
Abstract: Introducing Electromagnetic Interference and Electromagnetic Compatibility, or “The Art of Black Magic", for engineering students might be a terrifying experience both for students and tutors. Removing the obstacle of large, expensive facilities like a fully fitted EMC laboratory and hours of complex theory, this paper demonstrates a design of a laboratory setup for student exercises, giving students experience in the basics of EMC/EMI problems that may challenge the functionality and stability of embedded system designs. This is done using a simple laboratory installation and basic measurement equipment such as a medium cost digital storage oscilloscope, at the cost of not knowing the exact magnitude of the noise components, but rather if the noise is significant or not, as well as the source of the noise. A group of students have performed a trial exercise with good results and feedback.
Abstract: Numerical investigation of the characteristics of an 80°
delta wing in combined force-pitch and free-roll is presented. The
implicit, upwind, flux-difference splitting, finite volume scheme and
the second-order-accurate finite difference scheme are employed to
solve the flow governing equations and Euler rigid-body dynamics
equations, respectively. The characteristics of the delta wing in
combined free-roll and large amplitude force-pitch is obtained
numerically and shows a well agreement with experimental data
qualitatively. The motion in combined force-pitch and free-roll
significantly reduces the lift force and transverse stabilities of the delta
wing, which is closely related to the flying safety. Investigations on
sensitive factors indicate that the roll-axis moment of inertia and the
structural damping have great influence on the frequency and
amplitude, respectively. Moreover, the turbulence model is considered
as an influencing factor in the investigation.
Abstract: This paper presents an optimization of the hull
separation, i.e. transverse clearance. The main objective is to identify
the feasible speed ranges and find the optimum transverse clearance
considering the minimum wave-making resistance. The dimensions
and the weight of hardware systems installed in the catamaran
structured fuel cell powered USV (Unmanned Surface Vehicle) were
considered as constraints. As the CAE (Computer Aided Engineering)
platform FRIENDSHIP-Framework was used. The hull surface
modeling, DoE (Design of Experiment), Tangent search optimization,
tool integration and the process automation were performed by
FRIENDSHIP-Framework. The hydrodynamic result was evaluated
by XPAN the potential solver of SHIPFLOW.
Abstract: General as well as the MSW management in Thailand is reviewed in this paper. Topics include the MSW generation, sources, composition, and trends. The review, then, moves to sustainable solutions for MSW management, sustainable alternative approaches with an emphasis on an integrated MSW management. Information of waste in Thailand is also given at the beginning of this paper for better understanding of later contents. It is clear that no one single method of MSW disposal can deal with all materials in an environmentally sustainable way. As such, a suitable approach in MSW management should be an integrated approach that could deliver both environmental and economic sustainability. With increasing environmental concerns, the integrated MSW management system has a potential to maximize the useable waste materials as well as produce energy as a by-product. In Thailand, the compositions of waste (86%) are mainly organic waste, paper, plastic, glass, and metal. As a result, the waste in Thailand is suitable for an integrated MSW management. Currently, the Thai national waste management policy starts to encourage the local administrations to gather into clusters to establish central MSW disposal facilities with suitable technologies and reducing the disposal cost based on the amount of MSW generated.
Abstract: An approach and its implementation in 0.18 m CMOS process of the multichannel ASIC for capacitive (up to 30 pF) sensors are described in the paper. The main design aim was to study an analog data-driven architecture. The design was done for an analog derandomizing function of the 128 to 16 structure. That means that the ASIC structure should provide a parallel front-end readout of 128 input analog sensor signals and after the corresponding fast commutation with appropriate arbitration logic their processing by means of 16 output chains, including analog-to-digital conversion. The principal feature of the ASIC is a low power consumption within 2 mW/channel (including a 9-bit 20Ms/s ADC) at a maximum average channel hit rate not less than 150 kHz.
Abstract: This paper studies the dependability of componentbased
applications, especially embedded ones, from the diagnosis
point of view. The principle of the diagnosis technique is to
implement inter-component tests in order to detect and locate the
faulty components without redundancy. The proposed approach for
diagnosing faulty components consists of two main aspects. The first
one concerns the execution of the inter-component tests which
requires integrating test functionality within a component. This is the
subject of this paper. The second one is the diagnosis process itself
which consists of the analysis of inter-component test results to
determine the fault-state of the whole system. Advantage of this
diagnosis method when compared to classical redundancy faulttolerant
techniques are application autonomy, cost-effectiveness and
better usage of system resources. Such advantage is very important
for many systems and especially for embedded ones.
Abstract: It is known that symmetric encryption algorithms are
fast and easy to implement in hardware. Also elliptic curves have
proved to be a good choice for building encryption system. Although
most of the symmetric systems have been broken, we can create a
hybrid system that has the same properties of the symmetric
encryption systems and in the same time, it has the strength of
elliptic curves in encryption. As DES algorithm is considered the
core of all successive symmetric encryption systems, we modified
DES using elliptic curves and built a new DES algorithm that is hard
to be broken and will be the core for all other symmetric systems.
Abstract: Sensor relocation is to repair coverage holes caused by node failures. One way to repair coverage holes is to find redundant nodes to replace faulty nodes. Most researches took a long time to find redundant nodes since they randomly scattered redundant nodes around the sensing field. To record the precise position of sensor nodes, most researches assumed that GPS was installed in sensor nodes. However, high costs and power-consumptions of GPS are heavy burdens for sensor nodes. Thus, we propose a fast sensor relocation algorithm to arrange redundant nodes to form redundant walls without GPS. Redundant walls are constructed in the position where the average distance to each sensor node is the shortest. Redundant walls can guide sensor nodes to find redundant nodes in the minimum time. Simulation results show that our algorithm can find the proper redundant node in the minimum time and reduce the relocation time with low message complexity.
Abstract: Many applications require surface modification and
micro-structuring of polymers. For these purposes is mainly used
ultraviolet (UV) radiation from excimer lamps or excimer lasers.
However, these sources have a decided disadvantage - degrading the
polymer deep inside due to relatively big radiation penetration depth
which may exceed 100 μm. In contrast, extreme ultraviolet (EUV)
radiation is absorbed in a layer approximately 100 nm thick only. In
this work, the radiation from a discharge-plasma EUV source (with
wavelength 46.9 nm) based on a capillary discharge driver is focused
with a spherical Si/Sc multilayer mirror for surface modification of
PMMA sample or thin gold layer (thickness about 40 nm). It was
found that the focused EUV laser beam is capable by one shot to
ablate PMMA or layer of gold, even if the focus is significantly
influenced by astigmatism.
Abstract: A long-term campaign for monitoring the
concentration of atmospheric Particulate Matter (PM) was conducted
at multiple sites located in the center and suburbs of the Tokyo
Metropolitan Area in Japan. The concentration of fine PM has shown a
declining trend over the last two decades. A positive matrix
factorization model elucidated that the contribution of combustion
sources was drastically reduced. In Japan, the regulations on vehicle
exhaust emissions were phased in and gradually tightened over the last
two decades, which has triggered a notable reduction in PM emissions
from automobiles and has contributed to the mitigation of the problem
of fine PM pollution.
Abstract: This paper presents the design and analysis of a parallel
connected inverter configuration of. The configuration consists of
parallel connected three-phase dc/ac inverter. Series resistors added
to the inverter output to maintain same current in each inverter of the
two parallel inverters, and to reduce the circulating current in the
parallel inverters to the minimum. High frequency third harmonic
injection PWM (THIPWM) employed to reduce the total harmonic
distortion and to make maximum use of the voltage source. DSP was
used to generate the THIPWM and the control algorithm for the
converter. Selected experimental results have been shown to validate
the proposed system.
Abstract: Recently, Thai education system is engaged in serious and promising reforms. One of the crucial elements in most of these educational reforms is the teacher professional development. Teachers today are under growing pressure to perform. However, most new teachers are not adequately prepared to meet the expectation. Consequently, this paper seeks to investigate the opinion of mentor teachers and university supervisors about professional development in the aspect of learning management skill of the preservice teachers in Rajabhat Universities, then compare the opinion between the mentor teachers and university supervisors about professional development in the aspect of learning management skill of the pre-service teachers. The study involved a cohort of 40 university supervisors and 77 mentor teachers. The research concludes by showing that mentor teachers viewed pre-service teacher as a professional teacher with an effective learning management skill. However, in the perspective of the university supervisor, pre-service teachers still have inadequate learning management skill.
Abstract: The aim of the current study is to develop a numerical
tool that is capable of achieving an optimum shape and design of
hyperbolic cooling towers based on coupling a non-linear finite
element model developed in-house and a genetic algorithm
optimization technique. The objective function is set to be the
minimum weight of the tower. The geometric modeling of the tower
is represented by means of B-spline curves. The finite element
method is applied to model the elastic buckling behaviour of a tower
subjected to wind pressure and dead load. The study is divided into
two main parts. The first part investigates the optimum shape of the
tower corresponding to minimum weight assuming constant
thickness. The study is extended in the second part by introducing the
shell thickness as one of the design variables in order to achieve an
optimum shape and design. Design, functionality and practicality
constraints are applied.
Abstract: Knowledge is renowned as a significant component
for sustaining competitive advantage and gives leading edge in
business. This study emphasizes towards proper and effectuate
utilization of internal and external (both either explicit or tacit)
knowledge comes from stakeholders, highly supportive to combat
with the challenges and enhance organizational productivity.
Furthermore, it proposed a model under context of IRSA framework
which facilitates the organization including flow of knowledge and
experience sharing among employees. In discussion section an
innovative model which indulges all functionality as mentioned in
analysis section.
Abstract: The well known NP-complete problem of the Traveling Salesman Problem (TSP) is coded in genetic form. A software system is proposed to determine the optimum route for a Traveling Salesman Problem using Genetic Algorithm technique. The system starts from a matrix of the calculated Euclidean distances between the cities to be visited by the traveling salesman and a randomly chosen city order as the initial population. Then new generations are then created repeatedly until the proper path is reached upon reaching a stopping criterion. This search is guided by a solution evaluation function.
Abstract: In this study, control performance of a smart base
isolation system consisting of a friction pendulum system (FPS) and a
magnetorheological (MR) damper has been investigated. A fuzzy
logic controller (FLC) is used to modulate the MR damper so as to
minimize structural acceleration while maintaining acceptable base
displacement levels. To this end, a multi-objective optimization
scheme is used to optimize parameters of membership functions and
find appropriate fuzzy rules. To demonstrate effectiveness of the
proposed multi-objective genetic algorithm for FLC, a numerical
study of a smart base isolation system is conducted using several
historical earthquakes. It is shown that the proposed method can find
optimal fuzzy rules and that the optimized FLC outperforms not only a
passive control strategy but also a human-designed FLC and a
conventional semi-active control algorithm.