Abstract: This paper sets out a behavioral macro-model of a
Merged PiN and Schottky (MPS) diode based on silicon carbide
(SiC). This model holds good for both static and dynamic electrothermal
simulations for industrial applications. Its parameters have
been worked out from datasheets curves by drawing on the
optimization method: Simulated Annealing (SA) for the SiC MPS
diodes made available in the industry. The model also adopts the
Analog Behavioral Model (ABM) of PSPICE in which it has been
implemented. The thermal behavior of the devices was also taken
into consideration by making use of Foster’ canonical network as
figured out from electro-thermal measurement provided by the
manufacturer of the device.
Abstract: Rapid developments in technology in the present age
have made it necessary for communities to follow technological
developments and adapt themselves to these developments. One of
the fields that are most rapidly affected by these developments is
undoubtedly education. Determination of the attitudes of preservice
teachers, who live in an age of technology and get ready to raise
future individuals, is of paramount importance both educationally and
professionally. The purpose of this study was to analyze attitudes of
preservice teachers towards technology and some variables that
predict these attitudes (gender, daily duration of internet use, and the
number of technical devices owned). 329 preservice teachers
attending the education faculty of a large university in central Turkey
participated, on a volunteer basis, in this study, where relational
survey model was used as the research method. Research findings
reveal that preservice teachers’ attitudes towards technology are
positive and at the same time, the attitudes of male preservice
teachers towards technology are more positive than their female
counterparts. As a result of the stepwise multiple regression analysis
where factors predicting preservice teachers’ attitudes towards
technology, it was found that duration of daily internet use was the
strongest predictor of attitudes towards technology.
Abstract: Since the advances in digital imaging technologies have led to
development of high quality digital devices, there are a lot of illegal copies
of copyrighted video content on the Internet. Also, unauthorized editing is
occurred frequently. Thus, we propose an editing prevention technique for
high-quality (HQ) video that can prevent these illegally edited copies from
spreading out. The proposed technique is applied spatial and temporal gradient
methods to improve the fidelity and detection performance. Also, the scheme
duplicates the embedding signal temporally to alleviate the signal reduction
caused by geometric and signal-processing distortions. Experimental results
show that the proposed scheme achieves better performance than previously
proposed schemes and it has high fidelity. The proposed scheme can be used
in unauthorized access prevention method of visual communication or traitor
tracking applications which need fast detection process to prevent illegally
edited video content from spreading out.
Abstract: This report examines the current state of human gait
simulator development based on the human hip joint model. This unit
will create a database of human gait types, useful for setting up and
calibrating Mechano devices, as well as the creation of new systems
of rehabilitation, exoskeletons and walking robots. The system has
many opportunities to configure the dimensions and stiffness, while
maintaining relative simplicity.
Abstract: This paper presents the development of a mobile
application for students at the Faculty of Information Technology,
Rangsit University (RSU), Thailand. RSU upgrades an enrollment
process by improving its information systems. Students can
download the RSU APP easily in order to access the RSU substantial
information. The reason of having a mobile application is to help
students to access the system regardless of time and place. The objectives of this paper include: 1. To develop an application
on iOS platform for those students at the Faculty of Information
Technology, Rangsit University, Thailand. 2. To obtain the students’
perception towards the new mobile app. The target group is those
from the freshman year till the senior year of the faculty of
Information Technology, Rangsit University. The new mobile application, called as RSU APP, is developed by
the department of Information Technology, Rangsit University. It
contains useful features and various functionalities particularly on
those that can give support to students. The core contents of the app
consist of RSU’s announcement, calendar, events, activities, and ebook.
The mobile app is developed on the iOS platform. The user
satisfaction is analyzed from the interview data from 81 interviewees
as well as a Google application like a Google form which 122
interviewees are involved. The result shows that users are satisfied
with the application as they score it the most satisfaction level at 4.67
SD 0.52. The score for the question if users can learn and use the
application quickly is high which is 4.82 SD 0.71. On the other hand,
the lowest satisfaction rating is in the app’s form, apps lists, with the
satisfaction level as 4.01 SD 0.45.
Abstract: This study focuses on the stress analysis of Mandibular
Advancement Devices (MADs), which are considered as a standard
treatment of snoring that promoted by American Academy of Sleep
Medicine (AASM). Snoring is the most significant feature of
sleep-disordered breathing (SDB). SDB will lead to serious problems
in human health. Oral appliances are ensured in therapeutic effect and
compliance, especially the MADs. This paper proposes a new MAD
design, and the finite element analysis (FEA) is introduced to precede
the stress simulation for this MAD.
Abstract: Microcantilevers are the basic MEMS devices, which
can be used as sensors, actuators and electronics can be easily built
into them. The detection principle of microcantilever sensors is based
on the measurement of change in cantilever deflection or change in its
resonance frequency. The objective of this work is to explore the
analogies between mechanical and electrical equivalent of
microcantilever beams. Normally scientists and engineers working in
MEMS use expensive software like CoventorWare, IntelliSuite,
ANSYS/Multiphysics etc. This paper indicates the need of developing
electrical equivalent of the MEMS structure and with that, one can
have a better insight on important parameters, and their interrelation of
the MEMS structure. In this work, considering the mechanical model
of microcantilever, equivalent electrical circuit is drawn and using
force-voltage analogy, it is analyzed with circuit simulation software.
By doing so, one can gain access to powerful set of intellectual tools
that have been developed for understanding electrical circuits Later
the analysis is performed using ANSYS/Multiphysics - software based
on finite element method (FEM). It is observed that both mechanical
and electrical domain results for a rectangular microcantlevers are in
agreement with each other.
Abstract: We regard forecasting of energy consumption by
private production areas of a large industrial facility as well as by the
facility itself. As for production areas, the forecast is made based on
empirical dependencies of the specific energy consumption and the
production output. As for the facility itself, implementation of the
task to minimize the energy consumption forecasting error is based
on adjustment of the facility’s actual energy consumption values
evaluated with the metering device and the total design energy
consumption of separate production areas of the facility. The
suggested procedure of optimal energy consumption was tested based
on the actual data of core product output and energy consumption by
a group of workshops and power plants of the large iron and steel
facility. Test results show that implementation of this procedure gives
the mean accuracy of energy consumption forecasting for winter
2014 of 0.11% for the group of workshops and 0.137% for the power
plants.
Abstract: Gladiolus is an important cash crop and is grown
mainly for its elegant spikes. Traditionally the gladiolus corms are
planted manually which is very tedious, time consuming and labor
intensive operation. So far, there is no planter available for planting
of gladiolus corms. With a view to mechanize the planting operation
of this horticultural crop, a prototype of 4-row gladiolus planter was
developed and its performance was evaluated in-situ condition. Cupchain
type metering device was used to place each single gladiolus
corm in furrow at required spacing while planting. Three levels of
corm spacing viz 15, 20 and 25 cm and four levels of forward speed
viz 1.0, 1.5, 2.0 and 2.5 km/h was taken as evaluation parameter for
the planter. The performance indicators namely corm spacing in each
row, coefficient of uniformity, missing index, multiple index, quality
of feed index, number of corms per meter length, mechanical damage
to the corms etc. were determined during the field test. The data was
statistically analyzed using Completely Randomized Design (CRD)
for testing the significance of the parameters. The result indicated
that planter was able to drop the corms at required nominal spacing
with minor variations. The highest deviation from the mean corm
spacing was observed as 3.53 cm with maximum coefficient of
variation as 13.88%. The highest missing and quality of feed indexes
were observed as 6.33% and 97.45% respectively with no multiples.
The performance of the planter was observed better at lower forward
speed and wider corm spacing. The field capacity of the planter was
found as 0.103 ha/h with an observed field efficiency of 76.57%.
Abstract: Thermoacoustic refrigerator is a cooling device which
uses the acoustic waves to produce the cooling effect. The aim of this
paper is to explore the experimental and numerical feasibility of a
standing-wave thermoacoustic refrigerator. The effects of the stack
length, position of stack and operating frequency on the cooling
performance are carried out. The circular pore stacks are tested under
the atmospheric pressure. A low-cost loudspeaker is used as an
acoustic driver. The results show that the location of stack installed in
resonator tube has a greater effect on the cooling performance, than
the stack length and operating frequency, respectively. The
temperature difference across the ends of stack can be generated up
to 13.7°C, and the temperature of cold-end is dropped down by 5.3°C
from the ambient temperature.
Abstract: The post-rain puddles problem that occurs in the first
yard of Prambanan Temple are often disturbing visitor activity. A
poodle layer and a drainage system had ever built to avoid such a
problem, but puddles still did not stop appearing after rain.
Permeability parameter needs to be determined by using a simpler
procedure to find exact method of solution. The instrument modelling
was proposed according to the development of field permeability
testing instrument. This experiment used a proposed Constant
Discharge method. Constant Discharge method used a tube poured
with constant water flow from unsaturated until saturated soil
condition. Volumetric water content (θ) were monitored by soil
moisture measurement device. The results were correlations between
k and θ which were drawn by numerical approach from Van
Genutchen model. Parameters θr optimum value obtained from the
test was at very dry soil. Coefficient of permeability with a density of
19.8 kN/m3 for unsaturated conditions was in range of 3 x 10-6
cm/sec (Sr=68%) until 9.98 x 10-4 cm/sec (Sr=82%). The equipment
and testing procedure developed in this research was quite effective,
simple and easy to be implemented on determining field soil
permeability coefficient value of sandy soil. Using constant discharge
method in proposed permeability test, value of permeability
coefficient under unsaturated condition can be obtained without
establish soil water characteristic curve.
Abstract: The analytical bright two soliton solution of the 3-
coupled nonlinear Schrödinger equations with variable coefficients in
birefringent optical fiber is obtained by Darboux transformation
method. To the design of ultra-speed optical devices, Soliton
interaction and control in birefringence fiber is investigated. Lax pair
is constructed for N coupled NLS system through AKNS method.
Using two-soliton solution, we demonstrate different interaction
behaviors of solitons in birefringent fiber depending on the choice of
control parameters. Our results shows that interactions of optical
solitons have some specific applications such as construction of logic
gates, optical computing, soliton switching, and soliton amplification
in wavelength division multiplexing (WDM) system.
Abstract: The increase of technogenic and natural accidents,
accompanied by air pollution, for example, by combustion products,
leads to the necessity of respiratory protection. This work is devoted to the development of a calorimetric method
and a device which allows investigating quickly the kinetics of
carbon dioxide sorption by chemisorbents on the base of potassium
superoxide in order to assess the protective properties of respiratory
protective closed circuit apparatus. The features of the traditional approach for determining the
sorption properties in a thin layer of chemisorbent are described, as
well as methods and devices, which can be used for the sorption
kinetics study. The authors developed an approach (as opposed to the traditional
approach) based on the power measurement of internal heat sources
in the chemisorbent layer. The emergence of the heat sources is a
result of exothermic reaction of carbon dioxide sorption. This
approach eliminates the necessity of chemical analysis of samples
and can significantly reduce the time and material expenses during
chemisorbents testing. Error of determining the volume fraction of adsorbed carbon
dioxide by the developed method does not exceed 12%. Taking into
account the efficiency of the method, we consider that it is a good
alternative to traditional methods of chemical analysis under the
assessment of the protection sorbents quality.
Abstract: Increasingly complex modern power systems require
stability, especially for transient and small disturbances. Transient
stability plays a major role in stability during fault and large
disturbance. This paper compares a power system stabilizer (PSS)
and static Var compensator (SVC) to improve damping oscillation
and enhance transient stability. The effectiveness of a PSS connected
to the exciter and/or governor in damping electromechanical
oscillations of isolated synchronous generator was tested. The SVC
device is a member of the shunt FACTS (flexible alternating current
transmission system) family, utilized in power transmission systems.
The designed model was tested with a multi-machine system
consisting of four machines six bus, using MATLAB/SIMULINK
software. The results obtained indicate that SVC solutions are better
than PSS.
Abstract: Background: To improve the delivery of paediatric
healthcare in low resource settings, Community Health Workers
(CHW) have been provided with a paper-based set of protocols
known as Community Case Management (CCM). Yet research has
shown that CHW adherence to CCM guidelines is poor, ultimately
impacting health service delivery. Digitising the CCM guidelines via
mobile technology is argued in extant literature to improve CHW
adherence. However, little research exist which outlines how (a) this
process can be digitised and (b) adherence could be improved as a
result. Aim: To explore how an electronic mobile version of CCM
(eCCM) can overcome issues associated with the paper-based CCM
protocol (inadequate adherence to guidelines) vis-à-vis service
blueprinting. This service blueprint will outline how (a) the CCM
process can be digitised using mobile Clinical Decision Support
Systems software to support clinical decision-making and (b)
adherence can be improved as a result. Method: Development of a
single service blueprint for a standalone application which visually
depicts the service processes (eCCM) when supporting the CHWs,
using an application known as Supporting LIFE (SL eCCM app) as
an exemplar. Results: A service blueprint is developed which
illustrates how the SL eCCM app can be utilised by CHWs to assist
with the delivery of healthcare services to children. Leveraging
smartphone technologies can (a) provide CHWs with just-in-time
data to assist with their decision making at the point-of-care and (b)
improve CHW adherence to CCM guidelines. Conclusions: The
development of the eCCM opens up opportunities for the CHWs to
leverage the inherent benefit of mobile devices to assist them with
health service delivery in rural settings. To ensure that benefits are
achieved, it is imperative to comprehend the functionality and form
of the eCCM service process. By creating such a service blueprint for
an eCCM approach, CHWs are provided with a clear picture
regarding the role of the eCCM solution, often resulting in buy-in
from the end-users.
Abstract: Graphene, a single-atom sheet, has been considered as
the most promising material for making future nanoelectromechanical
systems as well as purely electrical switching with graphene
transistors. Graphene-based devices have advantages in scaled-up
device fabrication due to the recent progress in large area graphene
growth and lithographic patterning of graphene nanostructures. Here
we investigated its mechanical responses of circular graphene
nanoflake under the nanoindentation using classical molecular
dynamics simulations. A correlation between the load and the
indentation depth was constructed. The nanoindented force in this
work was applied to the center point of the circular graphene nanoflake
and then, the resonance frequency could be tuned by a nanoindented
depth. We found the hardening or the softening of the graphene
nanoflake during its nanoindented-deflections, and such properties
were recognized by the shift of the resonance frequency. The
calculated mechanical parameters in the force-vs-deflection plot were
in good agreement with previous experimental and theoretical works.
This proposed schematics can detect the pressure via the deflection
change or/and the resonance frequency shift, and also have great
potential for versatile applications in nanoelectromechanical systems.
Abstract: At the present work, highly transparent strip type
quasi-solid state dye-sensitized solar cells (DSSCs) were fabricated
through inkjet printing using nanocomposite TiO2 inks as raw
materials and tested under outdoor illumination conditions. The cells,
which can be considered as the structural units of large area modules,
were fully characterized electrically and electrochemically and after
the evaluation of the received results a large area DSSC module was
manufactured. The module design was a sandwich Z-interconnection
where the working electrode is deposited on one conductive glass and
the counter electrode on a second glass. Silver current collective
fingers were printed on the conductive glasses to make the internal
electrical connections and the adjacent cells were connected in series
and finally insulated using a UV curing resin to protect them from the
corrosive (I-/I3-) redox couple of the electrolyte. Finally, outdoor tests
were carried out to the fabricated dye-sensitized solar module and its
performance data were collected and assessed.
Abstract: Maintaining factory default battery endurance rate
over time in supporting huge amount of running applications on
energy-restricted mobile devices has created a new challenge for
mobile applications developer. While delivering customers’
unlimited expectations, developers are barely aware of efficient use
of energy from the application itself. Thus, developers need a set of
valid energy consumption indicators in assisting them to develop
energy saving applications. In this paper, we present a few software
product metrics that can be used as an indicator to measure energy
consumption of Android-based mobile applications in the early of
design stage. In particular, Trepn Profiler (Power profiling tool for
Qualcomm processor) has used to collect the data of mobile
application power consumption, and then analyzed for the 23
software metrics in this preliminary study. The results show that
McCabe cyclomatic complexity, number of parameters, nested block
depth, number of methods, weighted methods per class, number of
classes, total lines of code and method lines have direct relationship
with power consumption of mobile application.
Abstract: The growth in the demand of electrical energy is
leading to load on the Power system which increases the occurrence
of frequent oscillations in the system. The reason for the oscillations
is due to the lack of damping torque which is required to dominate
the disturbances of Power system. By using FACT devices, such as
Unified Power Flow Controller (UPFC) can control power flow,
reduce sub-synchronous resonances and increase transient stability.
Hence, UPFC is used to damp the oscillations occurred in Power
system. This research focuses on adapting the neuro fuzzy controller
for the UPFC design by connecting the infinite bus (SMIB - Single
machine Infinite Bus) to a linearized model of synchronous machine
(Heffron-Phillips) in the power system. This model gains the
capability to improve the transient stability and to damp the
oscillations of the system.
Abstract: The energy need is growing rapidly due to the
population growth and the large new usage of power. Several works
put considerable efforts to make the electricity grid more intelligent
to reduce essentially energy consumption and provide efficiency and
reliability of power systems. The Smart Grid is a complex
architecture that covers critical devices and systems vulnerable to
significant attacks. Hence, security is a crucial factor for the success
and the wide deployment of Smart Grids. In this paper, we present
security issues of the Smart Grid architecture and we highlight open
issues that will make the Smart Grid security a challenging research
area in the future.