TOJSAT - Volume 7 - Issue 3 - July 2017

Complete Issue's PDF file

 

A NEW METHOD IN NDT OF WOOD: THERMAL CONDUCTIVITY

Şeref KURT, Mustafa KORKMAZ, Cemal ÖZCAN, Türker DÜNDAR, Mustafa AKTAŞ

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Abstract:

NDT (Non-Destructive Testing) is a analysis technique of materials without causing
damage. Common techniques of NDT are ultrasonic, acoustic emission, penetrometer,
radiography etc. This methods depends on distinctive features of materials. NDT is used in a
variety of settings that covers a wide range of industrial activity, with new NDT methods and
applications, being continuously developed. Non-destructive testing methods are routinely
applied in industries where a failure of a component would cause significant hazard or economic
loss, such as in transportation, pressure vessels, building structures, piping, and hoisting
equipment. Thermal conductivity is a inherit feature of wood material and it is related with
density. In this study, a developed thermal conductivity based NDT device will be introduced
and it’s reliability will be exhibited.

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BIBLIOMETRIC ANALYSIS ON SCIENTIFIC RESEARCH ON INNOVATION DIFFUSION

Zeynep D. UNUTMAZ DURMUŞOĞLU, Pınar KOCABEY ÇİFTÇİ

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Abstract:

Innovation diffusion has become a large and growing field with considerable amount
of publications as the pioneering studies have appeared in the literature. In this context, the
main purpose of this paper is to analyze the scientific publications on innovation diffusion by
providing basic statistics (distributions of publications by document types, publication years,
authors' origins, and etc.) and distinct trends in publication topics. With this purpose, a
bibliometric analysis will be performed for a total of 900 papers published between January 1,
1981 and December 5, 2013. The findings of the study are expected to be helpful and insightful
for understanding the current state and trends of research on innovation diffusion and thereby
guiding researchers for their future studies.

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BIODIESEL FUEL OBTAINED FROM SUNFLOWER OIL AS AN ALTERNATIVE FUEL FOR DIESEL ENGINES

Cumali ILKILIC, Cengiz ÖNER

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Abstract:

In this study, an alternative diesel fuel, of which chemical modification was made
by transesterification with short chain methyl alcohols, was produced from sunflower oil, a
designated as B100. The modified products were then evaluated according to their fuel
properties as compared to diesel fuel. The fuel properties considered were viscosity, pour point,
calorific value, flash point, and cetane number in addition to some other properties. The effects
of sunflower oil methyl ester (biodiesel) and diesel fuel on a direct injected, four strokes, single
cylinder diesel engine performance were studied. The results showed that the performance of
the engine using biodiesel fuel differed very little from the engine’s using diesel fuel.

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COMPARATIVE EVALUATION OF REPLACEMENT FOUNDRY SAND WITH MINERAL FINE AGGREGATES ON HMA PROPERTIES

Bekir AKTAŞ, Şevket ASLAN

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Abstract:

In this study the influence of using waste foundry sand (WFS) as replacement for
mineral fine aggregates on the Hot Mix Asphalt (HMA) properties is evaluated. An
experimental program was conducted on the asphalt concrete samples prepared with 5%
replacement of mineral fine aggregates. HMA samples, made of WFS and conventional mineral
aggregate, were compared in terms of their Marshall Stability, Flow, Bulk Specific Gravity,
Void in Mineral Aggregates and Voids Filled with bitumen in the total mixture properties. The
results obtained from the experiments indicate that the replacement of WFS with mineral fine
aggregate has a significant potential to use in bituminous hot mixtures.

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COMPARATIVELY USE OF TIME SERIES AND ARTIFICIAL INTELLIGENCE METHODS IN THE PREDICTION OF AIR POLLUTANTS

Fatih TAŞPINAR, Kamran ABDOLLAHI

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Abstract:

Air pollution is a continuing environmental problem in many part of world which
affects welfare adversely. Air pollution monitoring data can thus be used to forecast
concentrations of air pollutants for short-term using time series and artificial intelligence
approaches. In this paper, time series modelling techniques, auto regressive integrated moving
average model and another type of it with exogenous variables (ARIMA and ARIMAX), and
artificial neural networks (ANNs) have been comparatively used to model particulate air
pollution (PM10) for predicting one-hour ahead concentration of particles in the air. An hourly
based data for the years 2015-2016 was composed with including meteorological factors and
air particulate concentration. The models were structured with inputting external parameters to
simulate air pollution better. ARIMAX(3,1,2) model with R2 of 0.667 and ANN(5-13-1) model
with R2 of 0.857 produced reasonable predictions over hourly dataset. The best fitting model
among these models have been chosen in further tests in the prediction of one-hour ahead PM10
concentrations.

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DESIGNING AND IMPLEMENTATION OF OUTDOOR TRANSFORMER SECURITY SYSTEM

Uğur Fidan, Naim Karasekreter

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Abstract:

In agriculture, quality and high productivity depend on irrigation of crops in dry
months. Pressurized irrigation methods are preferred due to both natural water resources more
efficiently as well as better quality agricultural production. This situation brings with it the
demand for electricity at irrigation. For this reason, the farmers are in need of transformers
supplied with their own resources owned or state. During unirrigated winter months, states cut
the energy of electrical transformers to eliminate or minimize energy losses occurred in
transmission lines. However, this condition has created serious problems in the transformer
security. In the previous studies, it is seen that many products have used GSM / GPRS
communications technology taken their energy from network or solar panels connected to
transformer. But, common feature of these products is a system that triggered by latching of lid
in the protection provided region and then generating alarm. In this study, it is focused on the
designing of security system triggered in the case of unauthorized persons to start approaching
or leaving the transformer pole and this is the only possible by using system integrated outdoor
PIR (Passive Infrared Sensor) sensors. In addition, developed Transformer Security System
(TSS) uses both GPRS and MMS infrastructure. In sleep mode, TSS register the GPRS network
in 4 seconds by receiving from the Passive Infrared Detector (PIR) and taking 5 seconds during
video recording with audio and visual stimuli. After then, with alarm status information and
image recording is transferred to the central monitoring software. As a result, security in the
field of medium voltage electrical transformer is provided by using M2M technology and the
continuity of the structure of interconnected power lines are protected.

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ENVIRONMENTAL MANAGEMENT SYSTEMS FOR PORT AREAS

Veysel TATAR

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Abstract:

This paper is a report the two main environmental management system (EMS)
standards EMAS and ISO 14001 environmental performance indicator for port industry.
The European Union (EU) is considered by some to have the most extensive environmental
laws of any international organization. Protection of the environment is a well-established
policy in the European Union. The environment has become a critical issue in business today.
Since the applications of logistics are generally positive for the efficiency of transport systems,
it has been suggested that logistics are environmentally friendly. Therefore organizations
systematic environmental programs are planned and documented way to manage the case.

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INFLUENCES OF PROCESS PARAMETERS ON THE QUALITY OF HYDROXYAPATITE COATING ON AZ91 MAGNESIUM ALLOY

Sevda ALBAYRAK, Henifi ÇİNİCİ, Recep ÇALIN, Canser CÖMERT

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Abstract:

Biodegradable materials such as AZ91 magnesium alloy arouse most of the
researchers’ interest in recent years. AZ91 Magnesium alloy is a potential alloy in order to use in
biomaterial applications as it is both light and similar to the mechanical features of bone.
However, this alloy shows corrosive behavior (in biological environment) in human body.
Extensive studies have been conducted to use of AZ91 Mg alloy as a biodegradable material. This
study focuses on the use of AZ91 Mg alloy as a permanent implant. As it is necessary to prevent
the corrosion of such alloy in the body, its surface was coated by sol-gel method with
hydroxyapatite material which has sufficient strength and tissue compatibility. The effects of
process parameters, i.e. different dipping numbers of sol-gel coating at the coating stage and
different sintering temperatures of these coatings, on coating quality was analyzed with Scanning
Electron Microscopy (SEM) and x-ray diffractometer (XRD).

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MDS CODES FROM POLYCYCLIC CODES OVER FINITE FIELDS

Mehmet Özen, Halit İnce

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Abstract:

In this work, we construct polycyclic codes over finite fields by using linear algebraic
methods. After the construction, we perform an exhaustive search by using polycyclic codes to
obtain MDS codes over finite fields which have many applications in cryptography. The
computer search results are presented at the end of the paper.

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NEIGHBOR INTEGRITY OF HARARY GRAPHS

Goksen BACAK-TURAN, Ferhan Nihan ALTUNDAG

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Abstract:

A network is a series of interconnected centers and transmission paths. A system like
transportation, communication, computer, logistics, etc., constitutes a network. Failure of the
links between stations, break down the centers, software faults on the network, hardware
malfunctions, transmission errors that may occur in various centers affect the quality of service
to be received over a network, more importantly, it causes a long interruption. In such a
situation, to know the vulnerability, the resistance of the network to disruption of operation
after the failure of certain stations or links until the system break down completely, is becoming
important. A network can be modelled by a graph representing the centers by vertices and the
links between the centers by edges. Various vulnerability parameters were defined in graph
theory to study the vulnerability of the networks. Connectivity, integrity, toughness, tenacity,
scattering number and rupture degree are some of the vulnerability parameters defined in graph
theory. But in spy networks, if a spy or a station is revealed, then the adjacent stations cannot
be trusted. Neighbor integrity is a vulnerability parameter that considers the neighborhoods and
hence can be applied to the spy networks. The neighbor integrity of a graph G is defined to be

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OPEN GREEN SPACES FUNCTION IN DESTINATION BRANDING: THE CASE OF BARTIN

Deniz ÇELİK

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Abstract:

Open green spaces are greatly important for the creation of sustainable cities in
social, cultural, economical and ecological sense. In our days, they have assumed other duties
in diverse areas in addition to these properties including the creation of urban identity and
destination branding. Destination branding is the indicator of the properties that differentiate
that destination from other destinations and describe its natural, cultural and man-made
properties. The aim of the study is to determine the principles of design for open green spaces
focusing on branding and identity in the process of branding of cities on the special example of
Bartın. The study has been carried out in the scope of a method consisting of five stages
including literature review and obtaining data, analysis of existing open green spaces in Bartın
City with land surveys, carrying out a questionnaire using the Analytical Hierarchy Process
(AHP); evaluating all the data obtained and submitting the results and recommendations. In
conclusion, open and green spaces are effective in the creation of destination branding and the
identity of the city.

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PERCEPTIONS OF BUSINESS PROFESSIONALS TOWARDS MOBILE

Süphan Nasır, Bengi Kurtuluş

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Abstract:

In today's world, mobile devices became an inevitable part of our lives. The main
purpose of this study is to find out perceptions of business professionals towards use of their
mobile device in the workplace as well as at the business meeting settings. To understand
business professionals’ mobile phone usage at the workplace, an online survey was conducted
with Turkish business professionals, who are members of Linked-in social network. Findings
of the study indicate the fact that, mobile phone usage at work is positively welcomed in
general. Respondents especially appreciate “the flexibility” and “the ability of doing a better
job” through accessing corporate emails and other business apps outside official working hours
and they strongly believe that “mobile phone usage at work is necessary”. However, they
slightly believe that their colleagues inappropriately use mobile phone at workplace. “Bringing
phone to the meeting”, “Excusing oneself to take a call”, and “Checking time” are among the
most appropriate mobile phone actions during the formal business meetings. On the other hand,
“Checking a social media account”, “Taking a call without excuse”, and “Browsing Internet
due to boredom” are seen inappropriate by most of the respondents.

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TEACHERS’ VIEWS ON THE USE OF INTERACTIVE EDUCATION WEBSITES IN SOCIAL STUDIES CLASSES

Nuray Kurtdede Fidan

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Abstract:

This study aims to determine the views of teachers on the use of interactive education
websites in social studies classes This study aims to determine interactive education websites
used by teachers in social studies classes according to their views. Participants were asked about
their opinions on the education websites they used in social studies classes, the benefits to
students and teachers, and the problems encountered. The participants of the study were 18
classroom teachers working in the city center and districts of Afyonkarahisar Province in the
spring term of the 2015–2016 academic year. Criterion sampling, a purposeful sampling
method, was used to determine the participants. A phenomenological design, a qualitative
research method, was used and data collection was conducted by using a Semi-Structured
Interview Form prepared by the researcher. A content analysis technique was used to analyze
the data. The data analysis showed that the interactive education websites used by the teachers
in their classes were mostly Morpa Kampüs and Okulistik, Vitamin and partially, EBA. The
study found that the teachers reported that the use of interactive education websites in social
studies classes offers many benefits to teachers and students.

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TECHNOLOGICAL SUSTAINABILITY OF MOBILE LEARNING

Abide Coskun-Setirek, Zuhal Tanrikulu

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Abstract:

This study aims to investigate and improve factors affecting technological sustainability of mlearning.
In addition to literature review, an investigation based on interviews was conducted with 11
heads and systems experts of distance education centers to obtain the technological sustainability factors
of m-learning. In order to understand the significance of these factors on m-learning sustainability,
another investigation based on survey research was conducted with 75 system staffs from the
universities which have m-learning facilities. The data analyzed and evaluated for a technological
sustainability model of m-learning. The study may provide guidelines to m-learning initiatives for a
sustainable mobile learning

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THE COLOR PREFERENCES OF CONSUMERS ON FURNITURE SURFACES

Hasan Huseyin CIRITCIOĞLU, Abdullah Cemil İLCE, Erol BURDURLU

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Abstract:

In this study, the color preferences of consumers were studied on the most applied
three finishing types on the furniture surfaces. These are transparent finishing, staining, and
opaque painting. In this direction, it was targeted to set forth the color preferences, which would
be the basis for the user-oriented design applications. A personal interview survey was prepared
for gathering data for this study. Some questions took place in the survey to determine color
and finishing type preferences of consumers according to their different demographic and
economic characteristics. It was contacted with a total of 479 consumers with the random
sampling method. The consumers were potential furniture buyers and living in the central
counties of Ankara, Turkey. The data collected by the survey were analyzed statistically and
the results were interpreted. In conclusion, the color and finishing type preferences of the
consumers on furniture surfaces show a variation according to demographic characteristics,
such as age, gender, marital status, educational level and income level.

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THE ECAT SOFTWARE PACKAGE TO ANALYZE EARTHQUAKE CATALOGUES

Tuba Eroğlu Azak

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Abstract:

Earthquakes are one of the most damaging natural disasters. Accordingly, earthquake
phenomenon has been an important subject in seismology and earthquake engineering. In order
to have insight on earthquakes, they have been compiled over the past years in databases called
as earthquake catalogues. In seismic hazard studies, earthquake catalogues are of prime
importance as they provide the most important features of earthquakes such as date, time,
location, magnitude, depth etc. Accordingly, earthquake catalogues are often utilized to model
seismicity. However, before such an implementation, earthquake catalogues need to be
undergone several analyses such as seismic declustering, assessment of completeness periods
and calculation of magnitude recurrence parameters. In order to perform these analyses, several
software packages are available for users on different programming platforms. Vast majority of
these software are only applicable to earthquake catalogues that are complete over the time
period they extend. However, most of the earthquake catalogues are incomplete in terms of
small and moderate size events particularly in the early years of instrumental period. This paper
illustrates some of the useful features of the software package called as ECAT that is generated
to compute completeness and magnitude recurrence parameters of earthquake catalogues whose
completeness periods are unequal for different magnitudes.

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THE EFFECTS OF DENSIFICATION AND HEAT TREATMENT ON THERMAL CONDUCTIVITY OF FIR WOOD

Hüseyin PELİT, Mustafa KORKMAZ, Mehmet BUDAKÇI, Raşit ESEN

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Abstract:

The goal of this study was to determine the effect of densification and heat treatment
on thermal conductivity properties of fir (Abies bornmulleriana Mattf.) wood. Fir wood
specimens were densified with compression ratios of 25% and 50%, and at 100 °C or 140 °C.
Then, the heat treatment was applied to the fir specimens at 185 ºC and 212 ºC for 2 hours
according to ThermoWood® method. The study results showed that, densification and thermal
treatment applications was effected thermal conductivity of the fir specimens. The thermal
conductivity increased based on compression ratios and temperatures in the densified
specimens. The thermal conductivity in the compressed specimens at high ratio (50%) was
found higher than other specimens. After densification, additionally, thermal conductivity
increasing on the radial surface was higher compared to the tangential surface. After heat
treatment, thermal conductivity of the all specimens decreased significantly depending on the
increase in treatment temperature. Particularly, the heat-treated fir specimens at 212 °C may
considerated where thermal insulation is important.

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THE EFFECTS OF SOCIAL MARKETING EFFORTS ON CONSUMERS: THE ICE BUCKET CHALLENGE

Selay ILGAZ SÜMER

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Abstract:

Marketers try to create behavioral changes by sending messages to the customers.
Sometimes various institutions and governments also present some messages in order to raise
awareness on social issues. These kind of marketing efforts are associated with social
marketing. Social marketing campaigns involve messages such as giving up smoking, avoid
using alcohol etc. In this study, it is aimed to determine the major effects of social marketing
efforts on consumers’ behaviors and thoughts. In order to find out these effects, the Ice Bucket
Challenge campaign was employed. In this research content analysis was applied to evaluate
the consumers’ thoughts in Turkey. For that purpose, various dictionaries such as “Eksi
Sozluk”, “ITU Sozluk” and “Uludag Sozluk” were used. Frequency analyses were performed
to analyze the consumers’ thoughts about Ice Bucket Challenge. At the end of the study it was
determined that Ice Bucket Challenge campaign influenced the consumers in different ways.

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THE LABORATORY IMPLICATIONS BASED ON ARGUMENTATION OF PRE-SERVICE SCIENCE TEACHERS

Bülent AYDOĞDU, Nil DUBAN

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Abstract:

The purpose of current study is to determine the effect of laboratory implications
based on argumentation on the pre-service science teachers’ logical thinking abilities and
critical thinking tendencies. The sample group of the study consists of a total of 64 pre-service
teachers (32 for the experimental group, 32 for the control group) who are in their fourth year
in the Science Education Program at a state university. The pre-test/ post-test control group
experimental design model was used that current research. In the experimental group, the
experiments were conducted using worksheets based on argumentation, whereas in the control
group the experiments were conducted in the form of a close-ended experiment. In this quasiexperimental
designed research, the “Logical Thinking Abilities Test” and “The California
Critical Thinking Disposition Inventory” were used as data collection tools. As a result of this
study, it was found that the logical thinking ability and critical thinking tendency levels of the
experimental group were higher than those of the control group. Accordingly, it can be argued
that laboratory activities conducted with argumentation-based worksheets are more effective
than laboratory activities conducted with the use of close-ended experiment in terms of
developing logical thinking abilities and critical thinking tendencies on the part of pre-service
science teachers.

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THE NEUTRON MACROSCOPIC CROSS SECTIONS CALCULATION OF SOME MINERALS BY USING FLUKA MONTE CARLO METHOD

Aybaba HANÇERLİOĞULLARI, Turgay KORKUT, Yosef G Ali MADEE

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Abstract:

Because of neutrons are uncharged particles, they are powerful in terms of
penetration into the material. Recently shielding is an important issue because of neutrons
which have many applications today do not harm living tissue. Different compounds, alloys
and composites are usually preferred against neutrons as shielding material. The aim of this
project is to determine minerals(Veatchite(Sr2B11O16(OH)5*(H2O), Sussexite(Mn+2BO2(OH)
and Vimsite(CaB2O2(OH)4 ),based new shielding materials against neutron particles using by
Fluka Monte Carlo method and then to obtain neutron total macroscopic cross sections and
several shielding parameters by experimentally.

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THE REFLECTION OF URBAN POVERTY ON CHILD POVERTY

Tahir Emre GENCER

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Abstract:

The most active and vulnerable subjects of the problems and challenges in urban
areas are children. Urban areas impact child development negatively. In various studies
conducted, it has been proven that child development and behaviour formation are determined
by the spaces interacted with rather than the intelligence and character. Therefore, the
environment with which the child interacts plays a crucial role in child development and
growing to be healthy individuals. This study aims to identify the negative impacts of
shortcomings in the planning of spaces and the lack of psycho-social support in this processes
as well as the negative impacts of urban poverty on children based on the interaction between
children and urban areas in order to ensure high benefit of children. This study has been
prepared within the scope of literature review. As the result of literature review conducted, it
has been identified that the risk of facing poverty and being affected by poverty is higher among
children compared to adults. Furthermore, it is stated that poverty experienced during childhood
could often be the indicator of poverty to be experienced during adulthood, as well.

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TOKAT – RESTORATION OF THE CARAVANSARAY OF PAZAR MAHPERI HATUN

Serdar Kasap, Başak Zengin

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Abstract:

One can easily find in the city centre of Tokat and nearby towns the fine examples
of Anatolian Turkish architecture belonging to the period of Seljuk such as mosques, shrines,
baths, fountains, khans and caravansarays which served distinctive functions. Many pieces of
art have been regenerated through proper methods of restoration with the contributions of wellinformed
local authorities and with the awareness of preservation of historic and cultural
heritage and desire to transfer them to the future. After the Battle of Manzikert (1071) the
Seljukians of Turkey ruled over some parts of Anatolia who attached importance to trade
infrastructures building caravansarays, bridges and sebils (wells and fountains) on trade roads
and turned Anotolia into Turkish-Islamic nation.
The construction of Seljukian caravansarays, which were the foundation of Anatolian
Economy, started during the ruling of Sultan Kılıç Arslan II (1155-1192) and devoloped in a
very short time spreading caravansarays all accoss the trade roads of Anatolia. Caravansarays
played imprortant role on development and continuity of transit trade in the Anatolian
geography as described in the resources of Seljukian period such as inscriptions, literary works
and travel books. Carvansarays, magnificient structures with their specific architecture and
decoration, were considerably modern stopover destionations according to the conditions of the
period. Considering the historical caravansarays as cultural entities to be preserved, it is vital to
document and preserve them as well as transfer them to next generations preserving their
material, technical and architectural features by means of proper methods of restoration. In this
study, a detailed structural survey of the Caravansaray of Mahperi Hatun has been made and
projects of restoration and restitution have been prepared. Following this, scientific evaluation
and reporting studies were carried out as well as reconstruction and reinforcement processes
were selected in the context of intervention types applicable to cultural premises which need to
be preserved. In the light of prepared projects and scientific data obtained thereafter, the
unusable materials have been selected to be removed from the structure and inventory of the
materials has been recorded. However, the usable materials have been enumarated and
stockpiled in order to be reused. The study remains faithful to the building survey. In
accordance with the inventory of unusable materials, most characteristacly similar natural
stones to be used in the materials have been brought from Tokat quarry so as to be applied.

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TORQUE AND FLUX RIPPLE MINIMIZATION OF DTC CONTROLLED IM BY USING FUZZY LOGIC DUTY-RATIO ESTIMATOR AND HYBRID FLUX OBSERVER

Yavuz USER

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Abstract:

Direct Torque Control (DTC) drive allows direct and independent control of flux
linkage and electromagnetic torque by the selection of optimum inverter switching tables. There
is no need for any complex transformation of current or voltage. However in the conventional
DTC induction motor drive there are torque and flux ripples, since none of the inverter
switching vectors is able to generate the exact stator voltage required to produce the desired
chances in the electromagnetic torque and stator flux linkage. In this study, we propose a
method to reduce torque and flux ripples. Two steps were carry out for this purpose. The first
step is to use duty-ratio. A selected inverter switching vector not for the entire switching period
as in conventional DTC, but only for a part of the switching period which is defined as the duty
ratio, δ and by using zero switching vector for the rest of period. The duty ratio determines the
average input voltage to the induction motor during the application of each switching vector as
δVdc. The duty ratio of each switching state is a non-linear function of the electromagnetic
torque error, stator flux-linkage error and a function of the position of the stator flux-linkage
space vector. In that case fuzzy-logic based duty-ratio control can be used because of it is
difficult to model its non-linear structure. The second step is to use hybrid flux observers. The
hybrid flux observer uses two model for high and low speeds. Accurate stator flux estimation
is obtained by using the stator voltage equation at high speeds, but low speeds accurate stator
flux estimation is obtained by the rotor voltage equation. The proposed method is simulated via
using MATLAB Simulink and compared to conventional DTC results. Comparing results
suggest that the proposed method reduced the ripples in electromagnetic torque, stator flux
linkage, stator currents and speed. Motor parameters, reference flux and torque values of motor
and load torque value of conventional and proposed methods are arranged to be same for the
comparison.

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USE OF MOLTEN SALT METHOD IN THE SYNTHESIS OF METAL HYDRIDE ELECTRODE MATERIALS

Mustafa ANIK

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Abstract:

La-Ni based alloys are being used in the commercial secondary nickel metal hydride
batteries. Economical synthesis of these alloys may cause large scale utilization of them
especially in the electrical vehicles. The electro-deoxidation, which is accepted as the
revolutionary technique in the extractive metallurgy, is very promising in the metal hydride
alloy synthesis since it provides direct synthesis of the alloys from their oxide raw materials. In
this study La(Ni0.8Co0.2)5 (AB5 type) and La2(Ni0.8Co0.2)7 (A2B7 type) alloys were synthesized
in the molten CaCl2 electrolyte at 850C and the charge/discharge characteristics of the
synthesized alloys were observed. Sintering caused the hygroscopic La2O3 to disappear and the
non-hygroscopic LaNiO3 to form. LaOCl was observed to form chemically upon contact of the
sintered pellet with the melt. The X-ray diffraction peaks indicated that the sinter products
reduced to LaNi5 and La2Ni7 phases within 2 h and 6 h electro-deoxidation process,
respectively. The sluggish reduction kinetics of LaOCl phase was observed to retard the
appearance of La2Ni7 phase. The discharge capacities of La(Ni0.8Co0.2)5 and La2(Ni0.8Co0.2)7
alloys were determined as 325 mA h g-1 and 332 mA h g-1, respectively. The results obtained
in this study showed that the electro-deoxidation technique is very promising in the synthesizing
of the high performance hydrogen storage alloys.

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VARIATION OF DRIVING CONCENTRATION WITH DRIVER PERCEPTION THROUGH IN-CAR VIEW ROAD SCENE AS VISUAL STIMULANT

Sevcan AYTAÇ KORKMAZ

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Abstract:

To make driver generate a right decision as evaluating scenes perceiving by his
brain, several factors (objects with different shapes, movements, and illuminations) that effects
on driving concentration are existed. In this study, continuously changing scenes that are seen
by driver eyes through windshield are statistically investigated. Here I have initially extracted a
set of features. Then I have found optimal feature subset using Linear discriminant analysis.
And then I get a measure to indicate driver concentration using Jensen Shannon Inequality and
Hellinger distance. It has been validated the measures via relationships between them.
Consequently, a model is proposed for seeking how the scene influencing on driver
concentration as an effective factor for comfortable driving. It suggests concentration risk
rate of fr is less than all the other road models. However, concentration risk rate of rsfs
is more than all the other road models.

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