Abstract: For smaller mechatronic device, especially for micro
Electronic system, a micro machining is a must. However, most
investigations on vibration of a mill have been limited to the
traditional type mill. In this article, vibration and dynamic
characteristics of a micro mill were investigated in this study. The
trend towards higher precision manufacturing technology requires
producing miniaturized components. To improve micro-milled
product quality, obtain a higher production rate and avoid milling
breakage, the dynamic characteristics of micro milling must be
studied. A stepped pre-twisted mill is used to simulate the micro mill.
The finite element analysis is employed in this work. The flute length
and diameter effects of the micro mill are considered. It is clear that
the effects of micro mill shape parameters on vibration in a micro mill
are significant.
Abstract: End milling process is one of the common metal
cutting operations used for machining parts in manufacturing
industry. It is usually performed at the final stage in manufacturing a
product and surface roughness of the produced job plays an
important role. In general, the surface roughness affects wear
resistance, ductility, tensile, fatigue strength, etc., for machined parts
and cannot be neglected in design. In the present work an
experimental investigation of end milling of aluminium alloy with
carbide tool is carried out and the effect of different cutting
parameters on the response are studied with three-dimensional
surface plots. An artificial neural network (ANN) is used to establish
the relationship between the surface roughness and the input cutting
parameters (i.e., spindle speed, feed, and depth of cut). The Matlab
ANN toolbox works on feed forward back propagation algorithm is
used for modeling purpose. 3-12-1 network structure having
minimum average prediction error found as best network architecture
for predicting surface roughness value. The network predicts surface
roughness for unseen data and found that the result/prediction is
better. For desired surface finish of the component to be produced
there are many different combination of cutting parameters are
available. The optimum cutting parameter for obtaining desired
surface finish, to maximize tool life is predicted. The methodology is
demonstrated, number of problems are solved and algorithm is coded
in Matlab®.
Abstract: Static Var Compensator (SVC) is a shunt type FACTS
device which is used in power system primarily for the purpose of
voltage and reactive power control. In this paper, a fuzzy logic based
supplementary controller for Static Var Compensator (SVC) is
developed which is used for damping the rotor angle oscillations and
to improve the transient stability of the power system. Generator
speed and the electrical power are chosen as input signals for the
Fuzzy Logic Controller (FLC). The effectiveness and feasibility of
the proposed control is demonstrated with Single Machine Infinite
Bus (SMIB) system and multimachine system (WSCC System)
which show improvement over the use of a fixed parameter
controller.
Abstract: The sanitary sewerage connection rate becomes an
important indicator of advanced cities. Following the construction of
sanitary sewerages, the maintenance and management systems are
required for keeping pipelines and facilities functioning well. These
maintenance tasks often require sewer workers to enter the manholes
and the pipelines, which are confined spaces short of natural
ventilation and full of hazardous substances. Working in sewers could
be easily exposed to a risk of adverse health effects. This paper
proposes the use of Bayesian belief networks (BBN) as a higher level
of noncarcinogenic health risk assessment of sewer workers. On the
basis of the epidemiological studies, the actual hospital attendance
records and expert experiences, the BBN is capable of capturing the
probabilistic relationships between the hazardous substances in sewers
and their adverse health effects, and accordingly inferring the
morbidity and mortality of the adverse health effects. The provision of
the morbidity and mortality rates of the related diseases is more
informative and can alleviate the drawbacks of conventional methods.
Abstract: Access to information is the key to the empowerment of everybody despite where they are living. This research is to be carried out in respect of the people living in developing countries, considering their plight and complex geographical, demographic, social-economic conditions surrounding the areas they live, which hinder access to information and of professionals providing services such as medical workers, which has led to high death rates and development stagnation. Research on Unified Communications and Integrated Collaborations (UCIC) system in the health sector of developing countries comes in to create a possible solution of bridging the digital canyon among the communities. The aim is to deliver services in a seamless manner to assist health workers situated anywhere to be accessed easily and access information which will help in service delivery. The proposed UCIC provides the most immersive Telepresence experience for one-to-one or many-tomany meetings. Extending to locations anywhere in the world, the transformative platform delivers Ultra-low operating costs through the use of general purpose networks and using special lenses and track systems.
Abstract: In this study Vitaton (an organic supplement which
contains fermentative β-carotene) and synthetic astaxanthin
(CAROPHYLL® Pink) were evaluated as pro-growth factors in
Rainbow trout diet. An 8 week feeding trial was conducted to
determine the effects of Vitaton versus astaxanthin on rearing factors,
survival rate and visual flesh color of Rainbow trout
(Oncorhnchynchus mykiss) with initial weight of 196±5. Four
practical diets were formulated to contain 50 and 80 (ppm) of β-
carotene and astaxanthin and also a control diet was prepared without
any pigment. Each diet was fed to triplicate groups of fish rearing in
fresh water. Fish were fed twice daily. The water temperature
fluctuated from 12 to 15 (C˚) and also dissolved oxygen content was
between 7 to 7.5 (mg/lit) during the experimental period. At the end
of the experiment, growth and food utilization parameters and
survival rate were unaffected by dietary treatments (p>0.05). Also,
there was no significant difference between carcass yield within
treatments (p>0.05). No significant difference recognized between
visual flesh color (SalmoFan score) of fish fed Vitaton-containing
diets. On the contrary, feeding on diets containing 50 and 80 (ppm)
of astaxanthin, increased SalmoFan score (flesh astaxanthin
concentration) from
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: 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 main objective of Automatic Generation Control (AGC) is to balance the total system generation against system load losses so that the desired frequency and power interchange with neighboring systems is maintained. Any mismatch between generation and demand causes the system frequency to deviate from its nominal value. Thus high frequency deviation may lead to system collapse. This necessitates a very fast and accurate controller to maintain the nominal system frequency. This paper deals with a novel approach of artificial intelligence (AI) technique called Hybrid Neuro-Fuzzy (HNF) approach for an (AGC). The advantage of this controller is that it can handle the non-linearities at the same time it is faster than other conventional controllers. The effectiveness of the proposed controller in increasing the damping of local and inter area modes of oscillation is demonstrated in a two area interconnected power system. The result shows that intelligent controller is having improved dynamic response and at the same time faster than conventional controller.
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 work, we perform numerical simulation of fluid
mixing in a floor-grooved micro-channel with wavy sidewalls which
may impose perturbation on the helical flow induced by the slanted
grooves on the channel floor. The perturbation is caused by separation
vortices in the recesses of the wavy-walled channel as the Reynolds
number is large enough. The results show that the effects of the wavy
sidewalls of the present micromixer on the enhancement of fluid
mixing increase with the increase of Reynolds number. The degree of
mixing increases with the increase of the corrugation angle, until the
angle is greater than 45 degrees. Besides, the pumping pressure of the
micromixer increases with the increase of the corrugation angle
monotonically. Therefore, we would suggest setting the corrugation
angle of the wavy sidewalls to be 45 degrees.
Abstract: Till date, English as a Second Language (ESL) educators involved in teaching language and communication to engineering students face an uphill task in developing graduate communicative competency. This challenge is accentuated by the apparent lack of English for Specific Purposes (ESP) materials for engineering students in the engineering curriculum. As such, most ESL educators are forced to play multiple roles. They don tasks such as curriculum designers, material writers and teachers with limited knowledge of the disciplinary content. Previous research indicates that prospective professional engineers should possess some sub-sets of competency: technical, linguistic oral immediacy, meta-cognitive and rhetorical explanatory competence. Another study revealed that engineering students need to be equipped with technical and linguistic oral immediacy competence. However, little is known whether these competency needs are in line with the educators- perceptions of communicative competence. This paper examines the best mix of communicative competence subsets that create the magic for engineering students in technical oral presentations. For the purpose of this study, two groups of educators were interviewed. These educators were language and communication lecturers involved in teaching a speaking course and content experts who assess students- technical oral presentations at tertiary level. The findings indicate that these two groups differ in their perceptions
Abstract: Petrol Fuel Station (PFS) has potential hazards to the
people, asset, environment and reputation of an operating company.
Fire hazards, static electricity air pollution evoked by aliphatic and
aromatic organic compounds are major causes of accident/incident
occurrence at fuel station. Activities such as carelessness,
maintenance, housekeeping, slips trips and falls, transportation
hazard, major and minor injuries, robbery and snake bites has a
potential to create unsafe conditions. The level of risk of these
hazards varies according to location and country. The emphasis on
safety considerations by the government is variable all around the
world. Developed countries safety records are much better as
compared to developing countries safety statistics. There is no
significant approach available to highlight the unsafe acts and unsafe
conditions during operation and maintenance of fuel station. Fuel
station is the most commonly available facilities that contain
flammable and hazardous materials. Due to continuous operation of
fuel station they pose various hazards to people, environment and
assets of an organization. To control these hazards, there is a need for
specific approach. PFS operation is unique as compared to other
businesses. For smooth operations it demands an involvement of
operating company, contractor and operator group. This study will
focus to address hazard contributing factors that have a potential to
make PFS operation risky. One year data collected, 902 activities
analyzed, comparisons were made to highlight significant
contributing factors. The study will provide help and assistance to
PFS outlet marketing companies to make their fuel station operation
safer. It will help health safety and environment (HSE) professionals
to arrest the gap available related to safety matters at PFS.
Abstract: One of the popular methods for recognition of facial
expressions such as happiness, sadness and surprise is based on
deformation of facial features. Motion vectors which show these
deformations can be specified by the optical flow. In this method, for
detecting emotions, the resulted set of motion vectors are compared
with standard deformation template that caused by facial expressions.
In this paper, a new method is introduced to compute the quantity of
likeness in order to make decision based on the importance of
obtained vectors from an optical flow approach. For finding the
vectors, one of the efficient optical flow method developed by
Gautama and VanHulle[17] is used. The suggested method has been
examined over Cohn-Kanade AU-Coded Facial Expression Database,
one of the most comprehensive collections of test images available.
The experimental results show that our method could correctly
recognize the facial expressions in 94% of case studies. The results
also show that only a few number of image frames (three frames) are
sufficient to detect facial expressions with rate of success of about
83.3%. This is a significant improvement over the available methods.
Abstract: The promises of component-based technology can only be fully realized when the system contains in its design a necessary level of separation of concerns. The authors propose to focus on the concerns that emerge throughout the life cycle of the system and use them as an architectural foundation for the design of a component-based framework. The proposed model comprises a set of superimposed views of the system describing its functional and non-functional concerns. This approach is illustrated by the design of a specific framework for data analysis and data acquisition and supplemented with experiences from using the systems developed with this framework at the Fermi National Accelerator Laboratory.
Abstract: Using spatial models as a shared common basis of
information about the environment for different kinds of contextaware
systems has been a heavily researched topic in the last years.
Thereby the research focused on how to create, to update, and to
merge spatial models so as to enable highly dynamic, consistent and
coherent spatial models at large scale. In this paper however, we
want to concentrate on how context-aware applications could use this
information so as to adapt their behavior according to the situation
they are in. The main idea is to provide the spatial model
infrastructure with a situation recognition component based on
generic situation templates. A situation template is – as part of a
much larger situation template library – an abstract, machinereadable
description of a certain basic situation type, which could be
used by different applications to evaluate their situation. In this
paper, different theoretical and practical issues – technical, ethical
and philosophical ones – are discussed important for understanding
and developing situation dependent systems based on situation
templates. A basic system design is presented which allows for the
reasoning with uncertain data using an improved version of a
learning algorithm for the automatic adaption of situation templates.
Finally, for supporting the development of adaptive applications, we
present a new situation-aware adaptation concept based on
workflows.
Abstract: The wireless sensor networks have been extensively
deployed and researched. One of the major issues in wireless sensor
networks is a developing energy-efficient clustering protocol.
Clustering algorithm provides an effective way to prolong the lifetime
of a wireless sensor networks. In the paper, we compare several
clustering protocols which significantly affect a balancing of energy
consumption. And we propose an Energy-Efficient Distributed
Unequal Clustering (EEDUC) algorithm which provides a new way of
creating distributed clusters. In EEDUC, each sensor node sets the
waiting time. This waiting time is considered as a function of residual
energy, number of neighborhood nodes. EEDUC uses waiting time to
distribute cluster heads. We also propose an unequal clustering
mechanism to solve the hot-spot problem. Simulation results show that
EEDUC distributes the cluster heads, balances the energy
consumption well among the cluster heads and increases the network
lifetime.
Abstract: The nature of adsorbed species on catalytic surface
over an industrial precipitated iron-based high temperature catalyst
during FTS was investigated by in-situ DRIFTS and chemical
trapping. The formulation of the mechanism of oxygenates formation
and key intermediates were also discussed. Numerous oxygenated
precursors and crucial intermediates were found by in-situ DRIFTS,
such as surface acetate, acetyl and methoxide. The results showed that
adsorbed molecules on surface such as methanol or acetaldehyde
could react with basic sites such as lattice oxygen or free surface
hydroxyls. Adsorbed molecules also had reactivity of oxidizing.
Moreover, acetyl as a key intermediate for oxygenates was observed
by investigation of CH3OH + CO and CH3I + CO + H2. Based on the
nature of surface properties, the mechanism of oxygenates formation
on precipitated iron-based high temperature catalyst was discussed.
Abstract: The mechanical behavior of porous media is governed by the interaction between its solid skeleton and the fluid existing inside its pores. The interaction occurs through the interface of gains and fluid. The traditional analysis methods of porous media, based on the effective stress and Darcy's law, are unable to account for these interactions. For an accurate analysis, the porous media is represented in a fluid-filled porous solid on the basis of the Biot theory of wave propagation in poroelastic media. In Biot formulation, the equations of motion of the soil mixture are coupled with the global mass balance equations to describe the realistic behavior of porous media. Because of irregular geometry, the domain is generally treated as an assemblage of fmite elements. In this investigation, the numerical formulation for the field equations governing the dynamic response of fluid-saturated porous media is analyzed and employed for the study of transient wave motion. A finite element model is developed and implemented into a computer code called DYNAPM for dynamic analysis of porous media. The weighted residual method with 8-node elements is used for developing of a finite element model and the analysis is carried out in the time domain considering the dynamic excitation and gravity loading. Newmark time integration scheme is developed to solve the time-discretized equations which are an unconditionally stable implicit method Finally, some numerical examples are presented to show the accuracy and capability of developed model for a wide variety of behaviors of porous media.