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Conference Object Citation - WoS: 4Citation - Scopus: 6A Reinforcement Learning Algorithm for Data Collection in Uav-Aided Iot Networks With Uncertain Time Windows(Ieee, 2021) Cicek, Cihan TugrulUnmanned aerial vehicles (UAVs) have been considered as an efficient solution to collect data from ground sensor nodes in Internet-of-Things (IoT) networks due to their several advantages such as flexibility, quick deployment and maneuverability. Studies on this subject have been mainly focused on problems where limited UAV battery is introduced as a tight constraint that shortens the mission time in the models, which significantly undervalues the UAV potential. Moreover, the sensors in the network are typically assumed to have deterministic working times during which the data is uploaded. In this study, we revisit the UAV trajectory planning problem with a different approach and revise the battery constraint by allowing UAVs to swap their batteries at fixed stations and continue their data collection task, hence, the planning horizon can be extended. In particular, we develop a discrete time Markov process (DTMP) in which the UAV trajectory and battery swapping times are jointly determined to minimize the total data loss in the network, where the sensors have uncertain time windows for uploading. Due to the so-called curse-of-dimensionality, we propose a reinforcement learning (RL) algorithm in which the UAV is trained as an agent to explore the network. The computational study shows that our proposed algorithm outperforms two benchmark approaches and achieves significant reduction in data loss.Article Impact of Operations on a Series Per Reliability Perspective(2025) Yucesan, OngunThe Mean Time Between Failure (MTBF) figures are the average of test durations between failure observations formed into a series. They can be seen to suit classical statistical distributions. An equally possible condition is that they are not stationary as a contradiction to the previous statement. In such worse conditions accepting availability of a concealed statistical property, this paper tries to identify the impact of Bi-sample Differencing and Bi-sample mean manipulations. In other words, operating on reliability observations series to reveal concealed statistical knowledge. Experimentation based on observation over a stationary series as a controlled experiment. As an outcome of experiments, the differencing seems to be alleviating the trend and seasonality to a degree. The bi-sample averaging is observed to be hiding variant conditions.Article Evaluation of Turkish Health System Capacity at Provincial Level by WISP Method Based on Weighting Methods(2025) Bulut, TevfikAmaç: Bu çalışmanın birincil amacı, Türkiye sağlık sisteminin kapasite ve kapasite açıklarını il düzeyinde göreceli olarak değerlendirmektir. Çalışmanın ikincil amacı ise R programlama dilinde kullanılan ağırlıklandırma yöntemleri için uygulama algoritmaları geliştirmektir. Yöntem: Sağlık sistemi kapasitesinin değerlendirilmesinde kullanılan karar kriterleri CRITIC, Shannon Entropy ve NMV yöntemleri ile ağırlıklandırılmıştır. İllerin sağlık sistemi kapasitesini değerlendirmek için WISP yöntemi kullanılmıştır. Veriler Sağlık Bakanlığı'nın 2022 Sağlık İstatistikleri Yıllığı'ndan alınmıştır. Bulgular: Tunceli, Bayburt ve Kilis, CRITIC tabanlı WISP skorlarına göre Türkiye'de sağlık sistemi kapasitesi açısından 81 il arasında optimal çözüme en yakın üç ildir. Buna karşılık, Bursa, İstanbul ve Şanlıurfa optimal çözümden en uzak üç ildir. Özgünlük: İl düzeyinde, sağlık sisteminin kapasitesindeki boşlukları tespit edebilir ve geliştirebiliriz. Kendi kendine yeterli sağlık sistemi kapasitesi oluşturabilir ve sağlık sistemini daha dirençli hale getirilebilir. Öte yandan, ağırlıklandırma yöntemleri için uygulama algoritmalarının geliştirilmesi önemli bir katkıdır. Böylece karar vericiler küçük ve özellikle büyük ölçekli veri setleri üzerinde anlık çözümler üretebilir.Article Citation - Scopus: 1A User Task Design Notation for Improved Software Design(PeerJ Inc., 2021) Ozcan,E.; Topalli,D.; Tokdemir,G.; Cagiltay,N.E.System design is recognized as one of the most critical components of a software system that bridges system requirements and coding. System design also has a significant impact on testing and maintenance activities, and on further improvements during the lifespan of the software system. Software design should reflect all necessary components of the requirements in a clear and understandable manner by all stakeholders of the software system. To distinguish system elements, separation of concerns in software design is suggested. In this respect, identification of the user tasks, i.e., the tasks that need to be performed by the user, is not currently reflected explicitly in system design documents. Our main assumption in this study is that software quality can be improved significantly by clearly identifying the user tasks from those that need to be performed by the computer system itself. Additionally, what we propose has the potential to better reflect the user requirements and main objectives of the system on the software design and thereby to improve software quality. The main aim of this study is to introduce a novel notation for software developers in the frame of UML Activity Diagram (UMLAD) that enables designers to identify the user tasks and define them separately from the system tasks. For this purpose, an extension of UML-AD, named UML-ADE (UML-Activity Diagram Extended) was proposed. Afterwards, it was implemented in a serious game case for which the specification of user tasks is extremely important. Finally, its effectiveness was analyzed and compared to UML-AD experimentally with 72 participants. The defect detection performance of the participants on both diagrams with two real-life serious game scenarios was evaluated. Results show a higher level of understandability for those using UML-ADE, which in turn may indicate a better design and higher software quality. The results encourage researchers to develop specific design representations dedicated to task design to improve system quality and to conduct further evaluations of the impact of these design on each of the above mentioned potential benefits for the software systems. © Copyright 2021 Ozcan et al.Article Discussions on Perturbed Quasi-Metric Spaces(Yokohama Publishing, 2025) Karapinar, ErdalThe main goal of this manuscript is to introduce the notion of perturbed quasi-metric spaces. Furthermore, it shall discuss the existence of basic fixed point theorems in the setting of perturbed quasi-metric spaces.Conference Object Citation - Scopus: 4Convolution Neural Network (cnn) Based Automatic Sorting of Cherries(Institute of Electrical and Electronics Engineers Inc., 2021) Park,H.; Khan,M.U.Cherries are spring fruits enriched with nutrients, and are easily available in food markets around the world. Due to their excess demand, many enterprises solely focused on their processing. Cherries are especially susceptible to pathological-, physiological-diseases and structural degradation due to their soft outer skin. The post-harvest life of the fruit is limited by various characteristics. The agricultural industry has also been at the forefront to get benefits from the advanced machine learning tools. This study presents an image processing-based system for sorting cherries using the convolutional neural network (CNN). For this study, Prunus avium L cherries of export quality, available in Turkey, tagged as ‘0900 Ziraat’, are used. Surprisingly, there exists no dataset for these cherries; hence, we developed our dataset. Through the proposed approach based upon U-Net, the binary classification accuracy of 99% is achieved. Clear identification is demonstrated by the test results of varying mixture ratios of good and bad cherries. It can therefore be said that for cherry sorting and grading, U-Net can be applied as a reliable and promising machine learning tool. ©2021 IEEEArticle Citation - WoS: 1Citation - Scopus: 1Outcomes of Transcatheter Aortic Valve Implantation in Patients With and Without Diabetes Mellitus(Soc Brasil Cirurgia Cardiovasc, 2024) Ayhan, Huseyin; Guney, Murat Can; Keles, Telat; Bozkurt, EnginIntroduction: Diabetes mellitus (DM) in patients undergoing cardiac transcatheter or surgical interventions usually is correlated with poor outcomes. Transcatheter aortic valve implantation (TAVI) has been developed as a therapy choice for inoperable, high-, or intermediate-risk surgical patients with severe aortic stenosis (AS). Objective: To evaluate the impact of DM and hemoglobin A1c (HbA1c) on outcomes and survival after TAVI. Methods: Five hundred and fifty-two symptomatic severe AS patients who underwent TAVI, of whom 164 (29.7%) had DM, were included in this retrospective study. Follow-up was performed after 30 days, six months, and annually. Results: The device success and risks of procedural-related complications were similar between patients with and without DM, except for acute kidney injury, which was more frequent in the DM group (2.4% vs. 0%, P=0.021). In-hospital and first-year mortality were similar between the groups (4.9% vs. 3.6%, P=0.490 and 15.0% vs. 11.2%, P=0.282, respectively). There was a statistical difference between HbA1c >= 6.5 and HbA1c <= 6.49 groups in total mortality (34.4% vs. 15.8%, P<0.001, respectively). The only independent predictors were Society of Thoracic Surgeons score (hazard ratio [HR] 1.28, 95% confidence interval [CI] 1.09-1.51; P=0.003) and HbA1c level >= 6.5 (HR 10.78, 95% CI 2.58-21.50; P=0.003) in multivariable logistic regression analysis. Conclusion: In this study, we conclude that DM was not correlated with an increased mortality risk or complication rates after TAVI. Also, it was shown that mortality was higher in patients with HbA1c >= 6.5, and it was an independent predictor for long-term mortality.Master Thesis Doğrusal Kablosuz Algılayıcı Ağlar için Bir Eşzamanlama Algoritması ve Link Katmanı Protokolün Gerçeklenmesi(2020) Imran, Md Abdullah Al; Kara, AliEşzamanlama, Kablosuz Algılayıcı Ağlar (KAA) gibi dağıtılmış ağ sistemlerinde büyük önem taşımaktadır. KAA'lar dağıtılmış varlıkların ve olayların koordinasyonu ve korelasyonu için eşzamanlamayı yaygın olarak kullanır. Tipik olarak, enerji, depolama, hesaplama ve bant genişliği gibi sınırlı kaynaklar, ortam koşulları ve uygulamaya özel gereksinimlerle birleştirilmiş sınırlı özellikleri nedeniyle, geleneksel eşzamanlama yöntemlerini olanaksız kılabilir. Bu nedenle, form faktörü, hassasiyet, işlem süresi ve gücü, bellek, trafik, verimlilik ve ölçeklenebilirlik gibi çok sayıda tasarım parametresi, KAA'ların eşzamanlanmasında çalışılmaktadır. Bu tez çalışmasında, doğrusal KAA'larda eşzamanlanma çalışılmış ve buna yönelik bütünsel bir protokol geliştirilerek deneysel sonuçlar irdelenmektedir. Geliştirilen protokol, düğümler üzerinden veri toplama ve basit hata işleme özellikleri ile donatılmıştır. Deneysel çalışmalar sonucunda, geliştirilen protokol ve eşzamanlama yönteminin etkinliği irdelenmiş ve ağ ömrünün optimizasyonlar ile arttırılabildiği gösterilmiştir. Bu kapsamda, eşzamanlamadaki kritik parametreler olan ofset ve zamanda kaymaların eşzamanlama doğruluğuna etkisi incelenmiştir. Yapılan testlerde, daha küçük eşzamanlama pencereleri ile daha yüksek bir eşzamanlama doğruluğu sağlanmaktadır. Buna bağlı olarak enerji tüketimi de optimize edilebilmektedir.Article Citation - WoS: 11Citation - Scopus: 13Challenges in Agile Software Maintenance for Local and Global Development: an Empirical Assessment(Mdpi, 2023) Almashhadani, Mohammed; Mishra, Alok; Yazici, Ali; Younas, MuhammadAgile methods have gained wide popularity recently due to their characteristics in software development. Despite the success of agile methods in the software maintenance process, several challenges have been reported. In this study, we investigate the challenges that measure the impact of agile methods in software maintenance in terms of quality factors. A survey was conducted to collect data from agile practitioners to establish their opinions about existing challenges. As a result of the statistical analysis of the data from the survey, it has been observed that there are moderately effective challenges in manageability, scalability, communication, collaboration, and transparency. Further research is required to validate software maintenance challenges in agile methods.Article Effectiveness of Boric Acid in Sepsis in Rats With Cecal Perforation(Springer Nature, 2025) Kurtipek, Ali Can; Dursun, Ali Dogan; Yigman, Zeynep; Ozdemir, Cagri; Kucuk, Aysegul; Gonullu, Ugur; Arslan, MustafaIntroduction and AimSepsis is a systemic inflammatory response that develops in the host against microorganisms, which results in end-organ damage. Boric acid (BA) has been shown to have immune modulatory effects in vitro and in animal studies. The aim of the study is to investigate the effects of high dose BA on lung and kidney tissues in rats with sepsis induced by the CLP method.Method28 rats were randomly divided into four groups: Group C (control group), Group BA, Group CLP (cecal ligation and puncture), and Group CLP + BA. Cecum was ligated below the ileocecal valve and punctured. BA was administered to the treatment groups at an intraperitoneal dose of 200 mg/kg, and at the end of 24 h, lung and kidney tissue samples were collected and evaluated for biochemical and histopathological parameters.ResultsHistopathologically, in kidney tissue, CLP + BA group showed significantly less peritubular capillary dilatation and brush border loss in the proximal tubule epithelium compared to the CLP group. In lung tissue, CLP + BA group had significantly less alveolar wall thickening compared to the CLP group. Biochemical analyses indicated that BA administration reduced oxidative stress in both renal and lung tissues.ConclusionWe found that intraperitoneal administration of high dose boric acid partially ameliorated the tissue damage in rats subjected to CLP induced sepsis. Further studies are needed regarding the dosage and application at different time points.
