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Fabrication and characterization of a solution processed flexible thermal sensor by using chemically synthesized GO and rGO
No full text2019 Innovations in Intelligent Systems and Applications Conference, ASYU 2019; 31 October 2019 through 2 November 2019Graphene oxide (GO) was reduced by ascorbic acid which is an environmental-friendly reductant and obtained sample was named as reduced GO (rGO). Stable dispersions of GO and rGO were prepared in N,N-Dimethylformamide (DMF). Compared to GO sample, rGO was determined to have more thermal stability, smaller sheet size and lower surface energy. GO and rGO dispersions were drop-casted on aluminum (Al) coated acetate substrate and used as thermal sensor. Fabricated sensors were tested from 25 °C to 150 °C. The sensors fabricated with GO, were not stabile against driven temperature changes. However, rGO ones, presented no thermal hysteresis effect after the first heating step. This sensor (Al/rGO/Al) acted like an NTC (Negative Temperature Coefficient) thermistor. The resistance of the rGO sensor was changed between 42 k? to 25 k? depending on the test temperature range (25 °C to 150 °C). Average beta value was calculated as 519.7649 K. © 2019 IEEE
Evaluating software security change requests: A COSMIC-based quantification approach
No full text45th Euromicro Conference on Software Engineering and Advanced Applications, SEAA 2019; 28 August 2019 through 30 August 2019Software project scope defines functional and non-functional requirements. These requirements may change to satisfy the customers' needs. However, the control of scope creep represents one of the success keys in software project management. Changes in non-functional requirements affect the ISO/IEC 25010 quality characteristics such as security, portability, etc. Furthermore, some of these quality characteristics may evolve throughout the software life cycle into functional requirements. In this paper, we explore the use of COSMIC method-ISO/IEC 19761 to quantify and evaluate security change requests. Measuring the functional size of security change requests allows stakeholders to make appropriate decisions about whether to accept, defer, or deny the change. © 2019 IEEE
Elimination of useless images from raw camera-trap data
No full textCamera-traps are motion triggered cameras that are used to observe animals in nature. The number of images collected from camera-traps has increased significantly with the widening use of camera-traps thanks to advances in digital technology. A great workload is required for wild-life researchers to group and label these images. We propose a system to decrease the amount of time spent by the researchers by eliminating useless images from raw camera-trap data. These images are too bright, too dark, blurred, or they contain no animals To eliminate bright, dark, and blurred images we employ techniques based on image histograms and fast Fourier transform. To eliminate the images without animals, we propose a system combining convolutional neural networks and background subtraction. We experimentally show that the proposed approach keeps 99% of photos with animals while eliminating more than 50% of photos without animals. We also present a software prototype that employs developed algorithms to eliminate useless images
SPL-AT Gherkin: A Gherkin extension for feature oriented testing of software product lines
No full text43rd IEEE-Computer-Society Annual International Computers, Software and Applications Conference (COMPSAC); JUL 15-19, 2019; Marquette Univ, Milwaukee, WIAs cloud platforms turn into software product lines (SPLs), testing products composed of customer selected features becomes more and more important. In this paper, we propose a feature-oriented testing approach for platform-based SPLs through a novel extension to Gherkin called SPL-AT Gherkin and a novel automatic test method generation technique, which utilizes TestNG framework. We demonstrate the applicability of the proposed approach by a case study
Evaluation of Wells Protection Zone for Environmental Pollutants Using Mathematical Modeling: A Case Study from Menderes (Izmir)
No full textİzmir Çevresinde alüvyon ve mermerler yeraltısuyu (YAS) sağlama açısından en önemli akiferlerdir. Alüvyon ve karstik birimlerden su sağlayan kuyuların koruma alanlarının belirlenmesi çevresel kirleticilerden korunması açısından önem arz etmektedir. İzmir Menderes Ovasında karstik birimlerle bağlantılı olan alüvyon akiferde açılan su kuyularının koruma alanlarının belirlenmesinde, farklı çekim değerlerinin etkileri parçacık taşınımı ile değerlendirilmiştir. Bunun için akiferle irtibatlı olan karstik birime bir kirletici tanımlanmış ve alüvyon akiferden su sağlayan kuyulara varış zamanları elde edilmiştir. Yapılan değerlendirmede, parçacığın hızının yeraltısuyu hidrodinamiğine bağlı olarak etkilendiği, bu hızın özellikle çekim debileri ile denetlediği belirlenmiştir. Alüvyon akiferde açılan sayısız sulama su kuyusu çekime başladığında kirleticiler daha hızlı kuyulara doğru ilerlemektedir. Özellikle kirleticilerin bulunduğu akiferlerde içme suyu kuyusu olarak açılan kuyuların koruma alanlarının belirlenmesi ve korumaya alınması önem taşımaktadır. Bunlara ek olarak, kuyu çekim değerlerinin yeraltısuyu akım hızını denetlemesi nedeniyle belli alanlarda kümelenmiş kuyuların koruma alanlarının belirlenmesinde modelleme yaklaşımı ile belirlenmesinde yarar bulunmaktadır.Alluvium and marble are the most important aquifers in term of groundwater supply in Izmir Region. Determinetion of the wells protection zone providing groundwater in alluvium and karstic aquifer is very important for the protection from the environmental pollutants. The assessment of protection zone of the groundwater wells drilled in alluvial aquifer connected on marble aquifer was evaluated under differend dicharge value by particle tracking. For this reason, a pollutant was defined on karstic unit that is connected to the alluvial aquifer and the groundwater arrival time was estimated to the providing water wells. It is observed that the velocity of the particle is influenced by the hydrodynamics of groundwater, especially by the discharge rate of wells. When a large namber of irrifation wells stard the dicharge from the aquifer, pollutant is moving towards the wells faster. It is vey important that the protection from the pollutants and the determination of protecton zone of drinking water wells and the protection from the pollutants. In addition, it is useful that the determination of clustered wells protection zone is need to groundwater modelling because of the well discharge values controls the groundwater flow rate
Sustainable management of rural-ecological commons: Recommendations on eDPSIR causal networks
No full textThis study aims to reveal the importance of the pastures as the rural-ecological commons in terms of biodiversity and ecological sustainability by focusing on the transformative impacts of the enclosure and commodification processes. Pastures are crucial especially within four dimensions: (1) rich biodiversity of flora and fauna; (2) rural development; (3) erosion prevention; and (4) rural tradition. Conflicts on the pastures and their triggering mechanisms are the main research interests of the study. Sustainable management of the rural-ecological commons has a potential to prevent the conflicts on the pastures. Three case study districts in Izmir (Turkey) are chosen to determine the conflicts on the pastures in relation with the recent legal regulations, determination, delimitation and allocation processes, malpractices and the civil responses. Data gathered from the interviews with professionals and village headmen, literature review, media analysis, and personal observations are evaluated by the content analysis to determine the main conflicts and the pasture dimensions for the eDPSIR (Driving force, Pressure, State, Impact, Response) model, which is an enhanced organisation tool to understand the multi-level relationships in environmental and social issues. The developed pasture dimension set evaluates the rural-ecological commons in relation with the actor relations and geographical aspects during the decision-making, common management and the planning processes
Engelliler için İzmir'deki kent politikalarının değerlendirilmesi
No full textThesis (Master)--Izmir Institute of Technology, City and Regional Planning, Izmir, 2019Includes bibliographical references (leaves: 58-68)Text in English; Abstract: Turkish and EnglishIn the world, more than 1 billion people are experiencing disability every day,
and the phenomenon of disability has been increasingly discussed each passing day.
That the individual mutually interacts with the built environment and society, moreover,
that physical and behavioral barriers from outside are concrete and abstract barriers that
limit the individual's activities are important approaches that have been discussed for a
long time. What is described here is that what creates the situation of 'being restricted'
or 'disability' is the restrictive environment, society's negative and wrong attitudes.
Although there are many regulations, studies and initiatives on disability and
accessibility approaches in our country, it is seen that there are insufficient holistic
studies, which are proceeded to remove physical and behavioral barriers and make
investments in the social sphere.
In this study, it was aimed to analyze the process of innovative policy making
and implementation, which deals with the concept of disability both physically and
socially, from a holistic perspective. In line with this aim, the 'Accessible Izmir Project'
of Izmir Metropolitan Municipality was examined as a case that handles the disability
phenomenon in the light of the socio-politic model and sees accessibility as a physical
and social phenomenon. This project is an initiative that aims to ensure accessibility, to
support initiatives in the social field, making studies to ensure the participation of the
disabled in public and social life, and to create a more livable and inclusive city in doing
so. In accordance with this purpose, within the scope of this project, studies are being
made to get rid of both physical and attitudinal barriers. While adopting incentive
approaches to provide accessibility, efforts are being made to break down perceptions
and approaches, which are negative, incomplete and wrong, against people with
disabilities. In this study, through the semi-structured interviews with the main actors of
this project, the dimensions of this sample, disability, and approaches to accessibility
are examined
Değişim etki analizi kullanılarak regresyon testi için test sınıflarının önceliklendirilmesi
No full textThesis (Doctoral)--Izmir Institute of Technology, Computer Engineering, Izmir, 2019Includes bibliographical references (leaves: 80-85)Text in English; Abstract: Turkish and EnglishThe test case prioritization aims to order test cases to increase rate of fault
detection, and to reduce the time for detecting faults. In this study, a static source code
analysis based approach, that uses change impact analysis is proposed. The proposed
change impact analysis approach uses program slicing technique, method change
information and Bayesian Network. With respect to the change impact analysis results,
two test case prioritization approaches called LoM and LoM-Addtl are proposed, which
is inspired by the "Law of Minimum" from biology and agronomy. The change impact
analysis and test case prioritization approaches are performed on three well-known
projects. The proposed change impact analysis results are evaluated with precision and
recall metrics. On the other hand, the proposed test case prioritization methods LoM and
LoM-Addtl are compared with five other test case prioritization techniques and evaluated
with the APFD measure. The results of the change impact analysis showed that when a
software has completed 75% of its development, 97%-100% of the affected methods and
changed methods are predicted. On the other hand, the LoM and LoM-Addtl test case
prioritization approaches showed consistent results when compared to the traditional test
case prioritization techniques. However, it has been observed that, LoM and LoM-Addtl
performed better than the traditional methods when version jumps are smaller.
Furthermore, following an Additional in LoM (LoM-Addtl) has shown better results
compare to LoM.Bu çalışmada, regresyon testinde ortaya çıkan test sınıfı önceliklendirilmesi problemi ele alınmıştır. Test sınıfı önceliklendirilmesinin amacı, test sınıflarını sıraya koyarak, hata yakalama oranının artırılması ve bu hataların daha kısa sürede bulunmasının sağlanmasıdır. Bu çalışmada, statik kaynak kod analizine dayalı,
değişiklik etki analizi kullanan bir yaklaşım önerilmiştir. Değişiklik etki analizi yaklaşımında program dilimleme, metod değişim bilgisi ve Bayes Ağları kullanılmıştır. Değişiklik etki analizi sonuçlarına göre, biyoloji ve tarım bilimindeki "Minimum Kanunu"ndan esinlenmiş olan LoM ve LoM-Addtl test sınıfı önceliklendirme yaklaşımları önerilmiştir. Değişiklik etki analizi ve test sınıfı önceliklendirme yaklaşımı
üç adet iyi bilinen projeye uygulanmıştır. Önerilen değişiklik etki analizinin sonuçları kesinlik ve geri getirme metriklerine göre değerlendirilmiştir. Bunun yanısıra, LoM ve LoM-Addtl test sınıfı önceliklendirme yöntemleri, beş farklı test önceliklendirme yöntemi ile APFD ölçümüne göre karşılaştırılmıştır. Değişiklik etki analizinin sonuçlarına göre, bir yazılımın yaklaşık %75’i tamamlandığında, etkilenen ve değişen
metodlar %97-%100 oranında tahmin edilmiştir. Diğer taraftan, LoM ve LoM-Addtl test sınıfı önceliklendirme yaklaşımları, geleneksel test sınıfı önceliklendirme yöntemleri ile karşılaştırıldığında tutarlı sonuçlar vermiştir. Ancak, LoM ile LoM-Addtl’nin bazı şartlar altında, versiyon atlamaları daha küçük olduğunda, geleneksel yöntemlerden daha iyi sonuçlar verdiği görülmüştür. Bununla beraber LoM üzerinde Additional yöntemi (LoM-Addtl) izlenilerek LoM’dan daha iyi sonuçlar elde edilmiştir
Stöber silika sentezi sırasındaki çekirdeklenme ve büyüme proseslerinin derinlemesine incelenmesi
No full textThesis (Doctoral)--Izmir Institute of Technology, Chemical Engineering, Izmir, 2019Includes bibliographical references (leaves: 108-120)Text in English; Abstract: Turkish and EnglishSilica nanoparticles (SNPs) which can be synthesized with high surface area,
controllable morphology and desired particle size have gained significant interests in
high-end applications such as catalysis, chemical sensors, cosmetics and drug delivery
applications. The sol-gel technique is the most commonly applied method for
manufacturing these particles owing to its simplicity and suitability for allowing surface
modifications to the final product. Though monodisperse amorphous SNPs have been
studied extensively, how their formation proceeds through nucleation and growth is still
a topic of debate. Over the years, a number of mathematical models have been suggested
for the nucleation and growth of SNPs; some suggesting that silica growth occurred
through monomer addition while some arguing that aggregation of nuclei/subparticles
were the dominant mechanism. Nevertheless, a clear understanding of the nucleation and
growth sub-processes is extremely important in control on the size and shape of SNPs for
those industrial applications which demand specific morphology and surface properties.
The need for a simple, robust and generalized model, both conceptually and
mathematically, to understand formation and growth of Stöber silica particles has been
the main driving force for this thesis. In this study, silica synthesis was carried out under
a wide variety of experimental conditions while determining the size distributions of the
formed particles kinetically during different stages of the synthesis in-situ through SEM
analysis using an image analysis software. The outcome of the extensive synthesis work
was to obtain a clear understanding of how the formation and growth of the silica particles
proceed during synthesis. This conceptual understanding of the nucleation and growth
processes was then translated into a mathematical model to predict the size of the particles
as a function of synthesis time.Yüksek yüzey alanları, ayarlanabilir morfolojileri ve istenilen boyutlarda
üretilebilmeleri nedeniyle, silika nanotaneler katalizörler, sensörler, kozmetik ürünler ve
ilaç taşıyıcılar gibi pek çok yüksek teknoloji uygulamalarında dikkate değer bir ilgi
görmektedir. Soljel tekniği, bu tanelerin üretiminde, kolay uygulanabilirliği ve sonuç
ürünün niteliklerinin modifikasyonuna olanak vermesi nedeniyle en yaygın kullanılan
yöntemdir. Her ne kadar amorf silika taneler sıklıkla çalışılsa da, tanelerin oluşumlarının
çekirdeklenme ve büyüme prosesleri ile nasıl ilerlediği sentezin kontrolü ve
tekrarlanabilirliği açısından hala bir tartışma konusudur. Yıllar boyunca, sol-jel silika
tanelerin çekirdeklenme ve büyüme prosesleri için bir takım matematiksel modeller
önerilmiş; kimi silika büyümesinin monomer ilavesi ile olduğunu öne sürmüş kimisi de
çekirdek/alt parçacıkların agregasyonun dominant mekanizma olduğunu tartışmıştır.
Yine de, çekirdeklenme ve büyüme alt proseslerinin açık bir şekilde anlaşılması, spesifik
morfoloji ve yüzey özellikleri gerektiren endüstriyel uygulamalar için silika tanelerin
boyut ve morfoloji kontrolü açısıdan son derece önemlidir.
Stöber silika tanelerin oluşum ve büyüme mekanizmalarının anlaşılması için
konsept ve matematik olarak, basit, sağlam ve genel bir modele olan gereksinim bu tezin
temel itici gücüdür. Bu çalışmada, silika sentezi geniş deneysel koşulları altında
uygulanmış, oluşan tanelerin boyut dağılımları kinetik olarak sentezin farklı
basamaklarında, bir görüntü analiz programı kullanılarak SEM analizlerinden elde
edilmiştir. Yoğun sentez çalışmalarının neticesi silika tanelerin sentez esnasında oluşum
ve büyüme proseslerinin net bir şekilde anlaşılırlığının sağlanmasıdır. Çekirdeklenme ve
büyüme proseslerinin konsept olarak anlaşılması ayrıca sentez zamanına karşı tanelerin
boyutunun tahmin edilebilmesine olanak sağlayan bir matematiksel modele aktarılmıştır
Energy dissipation and performance assessment of double damped outriggers in tall buildings under strong earthquakes
No full textThe use of a single set of outriggers equipped with oil viscous dampers increases the damping ratio of tall buildings in about 6–10%, depending on the loading conditions. However, could this ratio be further increased by the addition of another set of outriggers? Should this additional set include dampers too? To answer these questions, several double damped outrigger configurations for tall buildings are investigated and compared with an optimally designed single damped outrigger, located at elevation 0.7 of the total building's height (h). Using free vibration, double outrigger configurations increasing damping up to a ratio equal to the single-based optimal are identified. Next, selected configurations are subjected to several levels of eight ground motions to compare their capability for avoiding damage under critical excitations. Last, a simplified economic analysis highlights the advantages of each optimal configuration in terms of cost savings. The results show that, within the boundaries of this study, combining a damped outrigger at 0.5h with a conventional outrigger at 0.7h is more effective in reducing hysteretic energy ratios and economically viable if compared with a single damped outrigger solution. Moreover, double damped outrigger configurations for tall buildings exhibit broader display of optimal combinations, which offer flexibility of design to the high-rise architecture.Fondo de Fomento al Desarrollo Científico y Tecnológico (Grant 72100284