Abstract: Current transformers are an integral part of power
system because it provides a proportional safe amount of current for
protection and measurement applications. However, when the power
system experiences an abnormal situation leading to huge current
flow, then this huge current is proportionally injected to the
protection and metering circuit. Since the protection and metering
equipment’s are designed to withstand only certain amount of current
with respect to time, these high currents pose a risk to man and
equipment. Therefore, during such instances, the CT saturation
characteristics have a huge influence on the safety of both man and
equipment and on the reliability of the protection and metering
system. This paper shows the effect of burden on the Accuracy Limiting
factor/ Instrument security factor of current transformers and the
change in saturation characteristics of the CT’s. The response of the
CT to varying levels of overcurrent at different connected burden will
be captured using the data acquisition software LabVIEW. Analysis
is done on the real time data gathered using LabVIEW. Variation of
current transformer saturation characteristics with changes in burden
will be discussed.
Abstract: Salinity is one of the major factors limiting crop
production in an arid environment. Despite its global importance
soybean production suffer the problems of salinity stress causing
damages at plant development. So it is implacable to either search for
salinity enhancement of soybean plants. Therefore, in the current
study we try to clarify the mechanism that might be involved in the
ameliorating effects of osmo-protectants such as proline and glycine
betaine as well as, compost application on soybean plants grown
under salinity stress. The experiment was conducted under
greenhouse conditions at the Graduate School of Biosphere Science
Laboratory of Hiroshima University, Japan in 2011. The experiment
was designed as a spilt-split plot based on randomized complete
block design with four replications. The treatments could be
summarized as follows; (i) salinity concentrations (0 and 15 mM), (ii)
compost treatments (0 and 24 t ha-1) and (iii) the exogenous, proline
and glycine betaine concentrations (0 mM and 25 mM) for each.
Results indicated that salinity stress induced reduction in growth and
physiological aspects (dry weight per plant, chlorophyll content, N
and K+ content) of soybean plant compared with those of the
unstressed plants. On the other hand, salinity stress led to increases in
the electrolyte leakage ratio, Na and proline contents. Special
attention was paid to, the tolerance against salt stress was observed,
the improvement of salt tolerance resulted from proline, glycine
betaine and compost were accompanied with improved K+, and
proline accumulation. While, significantly decreased electrolyte
leakage ratio and Na+ content. These results clearly demonstrate that
harmful effect of salinity could reduce on growth aspects of soybean.
Consequently, exogenous osmoprotectants combine with compost
will effectively solve seasonal salinity stress problem and are a good
strategy to increase salinity resistance of soybean in the drylands.
Abstract: We report the design and characterization of ultra high
quality factor filter based on one-dimensional photonic-crystal Thue-
Morse sequence structure. The behavior of aperiodic array of
photonic crystal structure is numerically investigated and we show
that by changing the angle of incident wave, desired wavelengths
could be tuned and a tunable filter is realized. Also it is shown that
high quality factor filter be achieved in the telecommunication
window around 1550 nm, with a device based on Thue-Morse
structure. Simulation results show that the proposed structure has a
quality factor more than 100000 and it is suitable for DWDM
communication applications.
Abstract: Measuring the Electrocardiogram (ECG) signal is an
essential process for the diagnosis of the heart diseases. The ECG
signal has the information of the degree of how much the heart
performs its functions. In medical diagnosis and treatment systems,
Decision Support Systems processing the ECG signal are being
developed for the use of clinicians while medical examination. In this
study, a modular wireless ECG (WECG) measuring and recording
system using a single board computer and e-Health sensor platform
is developed. In this designed modular system, after the ECG signal
is taken from the body surface by the electrodes first, it is filtered and
converted to digital form. Then, it is recorded to the health database
using Wi-Fi communication technology. The real time access of the
ECG data is provided through the internet utilizing the developed
web interface.
Abstract: The availability to deploy mobile applications for
health care is increasing daily thru different mobile app stores. But
within these capabilities the number of hacking attacks has also
increased, in particular into medical mobile applications. The security
vulnerabilities in medical mobile apps can be triggered by errors in
code, incorrect logic, poor design, among other parameters. This is
usually used by malicious attackers to steal or modify the users’
information. The aim of this research is to analyze the vulnerabilities
detected in mobile medical apps according to risk factor standards
defined by OWASP in 2014.
Abstract: A new approach has been developed to estimate the
load share and distribution of worm gear drives, and to calculate the
instantaneous tooth meshing stiffness. In the approach, the worm gear
drive was modelled as a series of spur gear slices, and each slice was
analyzed separately using the well-established formulae of spur gear
loading and stresses. By combining the results obtained for all slices,
the entire envolute worm gear set loading and stressing was obtained. The geometric modelling method presented allows tooth elastic
deformation and tooth root stresses of worm gear drives under
different load conditions to be investigated. Based on the slicing
method introduced in this study, the instantaneous meshing stiffness
and load share are obtained. In comparison with existing methods,
this approach has both good analysis accuracy and less computing
time.
Abstract: This paper considers the design of Dual Proportional-
Integral (DPI) Load Frequency Control (LFC), using gravitational
search algorithm (GSA). The design is carried out for nonlinear
hydrothermal power system where generation rate constraint (GRC)
and governor dead band are considered. Furthermore, time delays
imposed by governor-turbine, thermodynamic process, and
communication channels are investigated. GSA is utilized to search
for optimal controller parameters by minimizing a time-domain based
objective function. GSA-based DPI has been compared to Ziegler-
Nichols based PI, and Genetic Algorithm (GA) based PI controllers
in order to demonstrate the superior efficiency of the proposed
design. Simulation results are carried for a wide range of operating
conditions and system parameters variations.
Abstract: Healthcare safety has been perceived important. It is
essential to prevent troubles in healthcare processes for healthcare
safety. Trouble prevention is based on trouble prediction using
accumulated knowledge on processes, troubles, and countermeasures.
However, information on troubles has not been accumulated in
hospitals in the appropriate structure, and it has not been utilized
effectively to prevent troubles. In the previous study, however a
detailed knowledge acquisition process for trouble prediction was
proposed, the knowledgebase for countermeasures was not involved.
In this paper, we aim to propose the structure of the knowledgebase for
countermeasures, in the knowledge acquisition process for trouble
prediction in healthcare process. We first design the structure of
countermeasures and propose the knowledge representation form on
countermeasures. Then, we evaluate the validity of the proposal, by
applying it into an actual hospital.
Abstract: Oxygen Reduction Reaction (ORR) performance of
iron and nitrogen co-doped porous carbon nanoparticles (Fe-NPC)
with various physical and (electro) chemical properties have been
investigated. Fe-NPC nanoparticles are synthesized via a facile
soft-templating procedure by using Iron (III) chloride hexa-hydrate as
iron precursor and aminophenol-formaldehyde resin as both carbon
and nitrogen precursor. Fe-NPC nanoparticles shows high surface area
(443.83 m2g-1), high pore volume (0.52 m3g-1), narrow mesopore size
distribution (ca. 3.8 nm), high conductivity (IG/ID=1.04), high kinetic
limiting current (11.71 mAcm-2) and more positive onset potential
(-0.106 V) compared to metal-free NPC nanoparticles (-0.295V)
which make it high efficient ORR metal-free catalysts in alkaline
solution. This study may pave the way of feasibly designing iron and
nitrogen containing carbon materials (Fe-N-C) for highly efficient
oxygen reduction electro-catalysis.
Abstract: This paper describes how to dimension the electric
components of a 48V hybrid system considering real customer use.
Furthermore, it provides information about savings in energy and
CO2 emissions by a customer-tailored 48V hybrid. Based on measured customer profiles, the electric units such as the
electric motor and the energy storage are dimensioned. Furthermore,
the CO2 reduction potential in real customer use is determined
compared to conventional vehicles. Finally, investigations are carried
out to specify the topology design and preliminary considerations in
order to hybridize a conventional vehicle with a 48V hybrid system.
The emission model results from an empiric approach also taking into
account the effects of engine dynamics on emissions. We analyzed
transient engine emissions during representative customer driving
profiles and created emission meta models. The investigation showed
a significant difference in emissions when simulating realistic
customer driving profiles using the created verified meta models
compared to static approaches which are commonly used for vehicle
simulation.
Abstract: In Automotive Industry, sliding door systems that are
also used as body closures are safety members. Extreme product tests
are realized to prevent failures in design process, but these tests
realized experimentally result in high costs. Finite element analysis is
an effective tool used for design process. These analyses are used
before production of prototype for validation of design according to
customer requirement. In result of this, substantial amount of time
and cost is saved. Finite element model is created for geometries that are designed in
3D CAD programs. Different element types as bar, shell and solid,
can be used for creating mesh model. Cheaper model can be created
by selection of element type, but combination of element type that
was used in model, number and geometry of element and degrees of
freedom affects the analysis result. Sliding door system is a good
example which used these methods for this study. Structural analysis
was realized for sliding door mechanism by using FE models. As
well, physical tests that have same boundary conditions with FE
models were realized. Comparison study for these element types,
were done regarding test and analyses results then optimum
combination was achieved.
Abstract: One of the fundamental characteristics of Information
and Communication Technology (ICT) has been the ever-changing
nature of continuous release and models of ICTs with its impact on
the academic, social, and psychological benefits of its introduction in
schools. However, there seems to be a growing concern about its
negative impact on students when introduced early in schools for
teaching and learning. This study aims to design a model of child
development factors affecting the early introduction of ICTs in
schools in an attempt to improve the understanding of child
development and introduction of ICTs in schools. The proposed
model is based on a sound theoretical framework. It was designed
following a literature review of child development theories and child
development factors. The child development theoretical framework
that fitted to the best of all child development factors was then chosen
as the basis for the proposed model. This study hence found that the
Jean Piaget cognitive developmental theory is the most adequate
theoretical frameworks for modeling child development factors for
ICT introduction in schools.
Abstract: This research will give the introductory ideas for
cultural adaption of B2C E-Service design in Germany. By the
intense competition of E-Service development, many companies have
realized the importance of understanding the emotional and cultural
characteristics of their customers. Ignoring customers’ needs and
requirements throughout the E-Service design can lead to faults,
mistakes, and gaps. The term of E-Service usability now is changed
not only to develop high quality E-Services, but also to be extended
to include customer satisfaction and provide for them to feel local.
Abstract: In this study, failure analysis of pipe system at a micro
hydroelectric power plant is investigated. Failure occurred at the pipe
system in the powerhouse during shut down operation of the water
flow by a valve. This locking had caused a sudden shock wave, also
called “Water-hammer effect”, resulting in noise and inside pressure
increase. After visual investigation of the effect of the shock wave on
the system, a circumference crack was observed at the pipe flange
weld region. To establish the reason for crack formation, calculations
of pressure and stress values at pipe, flange and welding seams were
carried out and concluded that safety factor was high (2.2), indicating
that no faulty design existed. By further analysis, pipe system and
hydroelectric power plant was examined. After observations it is
determined that the plant did not include a ventilation nozzle (air
trap), that prevents the system of sudden pressure increase inside the
pipes which is caused by water-hammer effect. Analyses were carried
out to identify the influence of water-hammer effect on inside
pressure increase and it was concluded that, according Jowkowsky’s
equation, shut down time is effective on inside pressure increase. The
valve closing time was uncertain but by a shut down time of even one
minute, inside pressure would increase by 7.6 bar (working pressure
was 34.6 bar). Detailed investigations were also carried out on the
assembly of the pipe-flange system by considering technical
drawings. It was concluded that the pipe-flange system was not
installed according to the instructions. Two of five weld seams were
not applied and one weld was carried out faulty. This incorrect and
inadequate weld seams resulted in; insufficient connection of the pipe
to the flange constituting a strong notch effect at weld seam regions,
increase in stress values and the decrease of strength and safety
factor.
Abstract: Erosion and abrasion are wear mechanisms reducing
the lifetime of machine elements like valves, pump and pipe systems.
Both wear mechanisms are acting at the same time, causing a
“Synergy” effect, which leads to a rapid damage of the surface.
Different parameters are effective on erosive abrasive wear rate. In
this study effect of particle impact angle on wear rate and wear
mechanism of ductile and brittle materials was investigated. A new
slurry pot was designed for experimental investigation. As abrasive
particle, silica sand was used. Particle size was ranking between 200-
500 μm. All tests were carried out in a sand-water mixture of 20%
concentration for four hours. Impact velocities of the particles were
4.76 m/s. As ductile material steel St 37 with Vickers Hardness
Number (VHN) of 245 and quenched St 37 with 510 VHN was used
as brittle material. After wear tests, morphology of the eroded
surfaces were investigated for better understanding of the wear
mechanisms acting at different impact angles by using Scanning
Electron Microscope. The results indicated that wear rate of ductile
material was higher than brittle material. Maximum wear rate was
observed by ductile material at a particle impact angle of 300 and
decreased further by an increase in attack angle. Maximum wear rate
by brittle materials was by impact angle of 450 and decreased further
up to 900. Ploughing was the dominant wear mechanism by ductile
material. Microcracks on the surface were detected by ductile
materials, which are nucleation centers for crater formation. Number
of craters decreased and depth of craters increased by ductile
materials by attack angle higher than 300. Deformation wear
mechanism was observed by brittle materials. Number and depth of
pits decreased by brittle materials by impact angles higher than 450.
At the end it is concluded that wear rate could not be directly related
to impact angle of particles due to the different reaction of ductile and
brittle materials.
Abstract: Nitrification is essential to biological processes
designed to remove ammonia and/or total nitrogen. It removes excess
nitrogenous compound in wastewater which could be very toxic to
the aquatic fauna or cause serious imbalance of such aquatic
ecosystem. Efficient nitrification is linked to an in-depth knowledge
of the structure and dynamics of the nitrifying community structure
within the wastewater treatment systems. In this study, molecular
technique was employed for characterizing the microbial structure of
activated sludge [ammonia oxidizing bacteria (AOB) and nitrite
oxidizing bacteria (NOB)] in a municipal wastewater treatment with
intention of linking it to the plant efficiency. PCR based phylogenetic
analysis was also carried out. The average operating and
environmental parameters as well as specific nitrification rate of plant
was investigated during the study. During the investigation the average temperature was 23±1.5oC.
Other operational parameters such as mixed liquor suspended solids
and chemical oxygen demand inversely correlated with ammonia
removal. The dissolved oxygen level in the plant was constantly
lower than the optimum (between 0.24 and 1.267 mg/l) during this
study. The plant was treating wastewater with influent ammonia
concentration of 31.69 and 24.47 mg/L. The influent flow rates
(ML/Day) was 96.81 during period. The dominant nitrifiers include:
Nitrosomonas spp. Nitrobacter spp. and Nitrospira spp. The AOB
had correlation with nitrification efficiency and temperature. This
study shows that the specific ammonia oxidizing rate and the specific
nitrate formation rates can serve as good indicator of the plant overall
nitrification performance.
Abstract: Hollow section for bridge columns has some
advantages. However, current seismic design codes do not provide
design regulations for hollow bridge piers. There have been many
experimental studied for hollow reinforced concrete piers in the world.
But, Study for hollow section for bridge piers in Korea has been begun
with approximately 2000s. There has been conducted experimental
study for hollow piers of flexural controlled sections by Yeungnam
University, Sung kyunkwan University, Korea Expressway
Corporation in 2009. This study concluded that flexural controlled
sections for hollow piers showed the similar behavior to solid sections.
And there have been conducted experimental study for hollow piers of
compression controlled sections by Yeungnam University, Korea
Institute of Construction Technology in 2012. This study concluded
that compression controlled sections for hollow piers showed
compression fracture of concrete in inside wall face. Samsung
Construction & Trading Corporation has been conducted study with
Yeungnam University for reduce the quantity of reinforcement details
about hollow piers. Reduce the quantity of reinforcement details are
triangular cross tie. This study concluded that triangular reinforcement
details showed the similar behavior as compared with existing
reinforcement details.
Abstract: This study aims to increase understanding of the
transition of business models in servitization. The significance of
service in all business has increased dramatically during the past
decades. Service-dominant logic (SDL) describes this change in the
economy and questions the goods-dominant logic on which business
has primarily been based in the past. A business model canvas is one
of the most cited and used tools in defining end developing business
models. The starting point of this paper lies in the notion that the
traditional business model canvas is inherently goods-oriented and
best suits for product-based business. However, the basic differences
between goods and services necessitate changes in business model
representations when proceeding in servitization. Therefore, new
knowledge is needed on how the conception of business model and
the business model canvas as its representation should be altered in
servitized firms in order to better serve business developers and interfirm
co-creation. That is to say, compared to products, services are
intangible and they are co-produced between the supplier and the
customer. Value is always co-created in interaction between a
supplier and a customer, and customer experience primarily depends
on how well the interaction succeeds between the actors. The role of
service experience is even stronger in service business compared to
product business, as services are co-produced with the customer. This paper provides business model developers with a service
business model canvas, which takes into account the intangible,
interactive, and relational nature of service. The study employs a
design science approach that contributes to theory development via
design artifacts. This study utilizes qualitative data gathered in
workshops with ten companies from various industries. In particular,
key differences between Goods-dominant logic (GDL) and SDLbased
business models are identified when an industrial firm
proceeds in servitization. As the result of the study, an updated version of the business
model canvas is provided based on service-dominant logic. The
service business model canvas ensures a stronger customer focus and
includes aspects salient for services, such as interaction between
companies, service co-production, and customer experience. It can be
used for the analysis and development of a current service business
model of a company or for designing a new business model. It
facilitates customer-focused new service design and service
development. It aids in the identification of development needs, and
facilitates the creation of a common view of the business model.
Therefore, the service business model canvas can be regarded as a
boundary object, which facilitates the creation of a common
understanding of the business model between several actors involved.
The study contributes to the business model and service business
development disciplines by providing a managerial tool for
practitioners in service development. It also provides research insight
into how servitization challenges companies’ business models.
Abstract: This paper will discuss how we optimize our physical
verification flow in our IC Design Department having various rule
decks from multiple foundries. Our ultimate goal is to achieve faster
time to tape-out and avoid schedule delay. Currently the physical
verification runtimes and memory usage have drastically increased
with the increasing number of design rules, design complexity, and
the size of the chips to be verified. To manage design violations, we
use a number of solutions to reduce the amount of violations needed
to be checked by physical verification engineers. The most important
functions in physical verifications are DRC (design rule check), LVS
(layout vs. schematic), and XRC (extraction). Since we have a
multiple number of foundries for our design tape-outs, we need a
flow that improve the overall turnaround time and ease of use of the
physical verification process. The demand for fast turnaround time is
even more critical since the physical design is the last stage before
sending the layout to the foundries.
Abstract: This paper is aimed to study combustion characteristics
of low NOx burner using petroleum cokes as fuel. The petroleum coke,
which is produced through the oil refining process, is an attractive fuel
in terms of its high heating value and low price. But petroleum coke is
a challenging fuel because of its low volatile content, high sulfur and
nitrogen content, which give rise to undesirable emission
characteristics and low ignitability. Therefore, the research and
development regarding the petroleum coke burner is needed for
applying this industrial system. In this study, combustion and emission
characteristics of petroleum cokes burner are experimentally
investigated in an industrial steam boiler. The low NOx burner is
designed to control fuel and air mixing to achieve staged combustion,
which, in turn reduces both flame temperature and oxygen. Air
distribution ratio of triple staged air is optimized experimentally. The
result showed that NOx concentration is lowest when overfire air is
used, and the burner function at a fuel rich condition. That is, the
burner is operated at the equivalence ratio of 1.67 and overall
equivalence ratio including overfire air is kept 0.87.