Abstract: Drought is one of the most serious problems posing a
grave threat to cereals production including maize. Maize
improvement in drought-stress tolerance poses a great challenge as
the global need for food and bio-energy increases. Thus, the current
study was planned to explore the variations and determine the
performance of target traits of maize hybrids at grain growth stage
under drought conditions during 2014 under Adana, Mediterranean
climate conditions, Turkey. Maize hybrids (Sancia, Indaco,
71May69, Aaccel, Calgary, 70May82, 72May80) were evaluated
under (irrigated and water stress). Results revealed that, grain yield
and yield traits had a negative effects because of water stress
conditions compared with the normal irrigation. As well as, based on
the result under normal irrigation, the maximum biological yield and
harvest index were recorded. According to the differences among
hybrids were found that, significant differences were observed among
hybrids with respect to yield and yield traits under current research. Based on the results, grain weight had more effect on grain yield
than grain number during grain filling growth stage under water
stress conditions. In this concern, according to low drought
susceptibility index (less grain yield losses), the hybrid (Indaco) was
more stable in grain number and grain weight. Consequently, it may
be concluded that this hybrid would be recommended for use in the
future breeding programs for production of drought tolerant hybrids.
Abstract: This paper presents the modeling approach in SBO
sequence for VVER 1000 reactors and describes the reactor core
behavior at late in-vessel phase in case of late reflooding by HPIS
and gives preliminary results for the ASTECv2 validation. The work
is focused on investigation of plant behavior during total loss of
power and the operator actions. The main goal of these analyses is to
assess the phenomena arising during the Station blackout (SBO)
followed by primary side high pressure injection system (HPIS)
reflooding of already damaged reactor core at very late “in-vessel”
phase. The purpose of the analyses is to define how the later HPIS
switching on can delay the time of vessel failure or possibly avoid
vessel failure. The times for HPP injection were chosen based on
previously performed investigations.
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: A sliding door system is used in commercial vehicles
and passenger cars to allow a larger unobstructed access to the
interior for loading and unloading. The movement of a sliding door
on vehicle body is ensured by mechanisms and tracks having special
cross-section which is manufactured by roll forming and stretch
bending process. There are three tracks and three mechanisms which
are called upper, central and lower on a sliding door system. There
are static requirements as strength on different directions, rigidity for
mechanisms, door drop off, door sag; dynamic requirements as high
energy slam opening-closing and durability requirement to validate
these products. In addition, there is a kinematic requirement to find
out force values from door handle during manual operating. In this
study, finite element analysis and physical test results which are
realized for sliding door systems will be shared comparatively.
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: Damaturu is the capital of Yobe State in northeastern
Nigeria where civic amenities and facilities are not adequate even
after 24 years of its existence. The volatile security and political
situations are most significant causes for the same. The basic facility
for the citizens in terms of drinking water and electricity are not
available. For the drinking water, they have to rely on personal
boreholes or the filtered borehole waters available in packaged
sachets in market. The present study is concerned with environmental
impact of indiscriminate disposal of drinking synthetic polythene
water sachets in Damaturu. The sachet water is popularly called as
“pure water”, but its purity is questionable. Increased production and
consumption of sachet water has led to indiscriminate dumping and
disposal of empty sachets leading to serious environmental threat.
The evidence of this is seen for sachets littering the streets and the
drainages blocked by ‘blocks’ of water sachet waste. Sachet water
gained much popularity in Nigeria because the product is convenient
for use, affordable and economically viable. The present study aims
to find out the solution to this environmental problem. The fieldbased
study has found some significant factors that cause
environmental and socio economic effect due to this. Some
recommendations have been made based on research findings
regarding sustainable waste management, recycling and re-use of the
non-biodegradable products in society.
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: There are a number of Distributed Generations (DGs)
installed in microgrid, which may have diverse path and direction of
power flow or fault current. The overcurrent protection scheme for the
traditional radial type distribution system will no longer meet the
needs of microgrid protection. Integrating the Intelligent Electronic
Device (IED) and a Supervisory Control and Data Acquisition
(SCADA) with IEC 61850 communication protocol, the paper
proposes a Microgrid Protection Management System (MPMS) to
protect power system from the fault. In the proposed method, the
MPMS performs logic programming of each IED to coordinate their
tripping sequence. The GOOSE message defined in IEC 61850 is used
as the transmission information medium among IEDs. Moreover, to
cope with the difference in fault current of microgrid between
grid-connected mode and islanded mode, the proposed MPMS applies
the group setting feature of IED to protect system and robust
adaptability. Once the microgrid topology varies, the MPMS will
recalculate the fault current and update the group setting of IED.
Provided there is a fault, IEDs will isolate the fault at once. Finally, the
Matlab/Simulink and Elipse Power Studio software are used to
simulate and demonstrate the feasibility of the proposed method.
Abstract: This paper addresses minimizing the makespan of the
distributed permutation flow shop scheduling problem. In this
problem, there are several parallel identical factories or flowshops
each with series of similar machines. Each job should be allocated to
one of the factories and all of the operations of the jobs should be
performed in the allocated factory. This problem has recently gained
attention and due to NP-Hard nature of the problem, metaheuristic
algorithms have been proposed to tackle it. Majority of the proposed
algorithms require large computational time which is the main
drawback. In this study, a general variable neighborhood search
algorithm (GVNS) is proposed where several time-saving schemes
have been incorporated into it. Also, the GVNS uses the sophisticated
method to change the shaking procedure or perturbation depending
on the progress of the incumbent solution to prevent stagnation of the
search. The performance of the proposed algorithm is compared to
the state-of-the-art algorithms based on standard benchmark
instances.
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 aims to study the heat transfer and fluid
flow characteristics of nanofluids used in spray cooling systems. The
effect of spray height, type of nanofluids and concentration of
nanofluids are numerically investigated. Five different nanofluids
such as AgH2O, Al2O3, CuO, SiO2 and TiO2 with volume fraction
range of 0.5% to 2.5% are used. The results revealed that the heat
transfer performance decreases as spray height increases. It is found
that TiO2 has the highest transfer coefficient among other nanofluids.
In dilute spray conditions, low concentration of nanofluids is
observed to be more effective in heat removal in a spray cooling
system.
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: The current tools for real time management of sewer
systems are based on two software tools: the software of weather
forecast and the software of hydraulic simulation. The use of the first
ones is an important cause of imprecision and uncertainty, the use of
the second requires temporal important steps of decision because of
their need in times of calculation. This way of proceeding fact that
the obtained results are generally different from those waited. The major idea of this project is to change the basic paradigm by
approaching the problem by the "automatic" face rather than by that
"hydrology". The objective is to make possible the realization of a
large number of simulations at very short times (a few seconds)
allowing to take place weather forecasts by using directly the real
time meditative pluviometric data. The aim is to reach a system
where the decision-making is realized from reliable data and where
the correction of the error is permanent. A first model of control laws was realized and tested with different
return-period rainfalls. The gains obtained in rejecting volume vary
from 19 to 100 %. The development of a new algorithm was then
used to optimize calculation time and thus to overcome the
subsequent combinatorial problem in our first approach. Finally, this
new algorithm was tested with 16- year-rainfall series. The obtained
gains are 40 % of total volume rejected to the natural environment
and of 65 % in the number of discharges.
Abstract: When high strength reinforced concrete is exposed to
high temperature due to a fire, deteriorations occur such as loss in
strength and elastic modulus, cracking and spalling of the concrete.
Therefore, it is important to understand risk of structural safety in
building structures by studying structural behaviors and rehabilitation
of fire damaged high strength concrete structures. This paper aims at
investigating rehabilitation effect on fire damaged high strength
concrete beams using experimental and analytical methods. In the
experiments, flexural specimens with high strength concrete are
exposed to high temperatures according to ISO 834 standard time
temperature curve. From four-point loading test, results show that
maximum loads of the rehabilitated beams are similar to or higher than
those of the non-fire damaged RC beam. In addition, structural
analyses are performed using ABAQUS 6.10-3 with same conditions
as experiments to provide accurate predictions on structural and
mechanical behaviors of rehabilitated RC beams. The parameters are
the fire cover thickness and strengths of repairing mortar. Analytical
results show good rehabilitation effects, when the results predicted
from the rehabilitated models are compared to structural behaviors of
the non-damaged RC beams. In this study, fire damaged high strength concrete beams are
rehabilitated using polymeric cement mortar. The predictions from the
finite element (FE) models show good agreements with the
experimental results and the modeling approaches can be used to
investigate applicability of various rehabilitation methods for further
study.
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.
Abstract: Recently attention has been focused on incomplete
spinal cord injuries (SCI) to the central spine caused by pressure on
parts of the white matter conduction pathway, such as the pyramidal
tract. In this paper, we focus on a training robot designed to assist with
primary walking-pattern training. The target patient for this training
robot is relearning the basic functions of the usual walking pattern; it is
meant especially for those with incomplete-type SCI to the central
spine, who are capable of standing by themselves but not of
performing walking motions. From the perspective of human
engineering, we monitored the operator’s actions to the robot and
investigated the movement of joints of the lower extremities, the
circumference of the lower extremities, and exercise intensity with the
machine. The concept of the device was to provide mild training
without any sudden changes in heart rate or blood pressure, which will
be particularly useful for the elderly and disabled. The mechanism of
the robot is modified to be simple and lightweight with the expectation
that it will be used at home.
Abstract: In some applications, such as image recognition or
compression, segmentation refers to the process of partitioning a
digital image into multiple segments. Image segmentation is typically
used to locate objects and boundaries (lines, curves, etc.) in images.
Image segmentation is to classify or cluster an image into several
parts (regions) according to the feature of image, for example, the
pixel value or the frequency response. More precisely, image
segmentation is the process of assigning a label to every pixel in an
image such that pixels with the same label share certain visual
characteristics. The result of image segmentation is a set of segments
that collectively cover the entire image, or a set of contours extracted
from the image. Several image segmentation algorithms were
proposed to segment an image before recognition or compression. Up
to now, many image segmentation algorithms exist and be
extensively applied in science and daily life. According to their
segmentation method, we can approximately categorize them into
region-based segmentation, data clustering, and edge-base
segmentation. In this paper, we give a study of several popular image
segmentation algorithms that are available.
Abstract: This paper investigates the thermal issue of permanent
magnet synchronous generator which is frequently used in direct
drive gearless small-scale wind turbine applications. Permanent
Magnet Synchronous Generator (PMSG) is designed with 2.5 kW
continuous and 6 kW peak power. Then considering generator
geometry, mechanical design of wind turbine is performed. Thermal
analysis and optimization is carried out considering all wind turbine
components to reach realistic results. This issue is extremely
important in research and development (R&D) process for wind
turbine applications.