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Uav-Bs Trajectory Optimization Under Coverage, Backhaul and Qos Constraints Using Q-Learning
No full text2022 International Balkan Conference on Communications and Networking, BalkanCom 2022 -- 22 August 2022 through 24 August 2022 -- 183326In this study, three-dimensional optimal trajectory planning is performed for the Unmanned Aerial Vehicle (UAV) with the base station (BS) attached to it to increase the service provided to the users. The case that heterogeneous quality of service (QoS) requirements for different users are considered. While planning the trajectory, the coverage area of the UAV-BS and backhaul capacity between the UAV-BS and Ground Base Station (GBS) are limited. Under these constraints, the aim is to find a trajectory for the UAV-BS that maximizes the total data rate provided to the users during the flight using reinforcement learning. With the application of Q-learning in our problem, the UAV-BS learns to take action to achieve the desired goal. As a result of trial and error processes with different learning parameters, appropriate parameters are determined and a reinforcement learning model is trained. Different communication scenarios are compared for analyzing the effects of the constraints. According to the effects of the mentioned constraints and heterogeneous QoS demands, UAV-BS's trajectory preferences and total transmission rate changes are examined. Three prominent results shows the effects of coverage, backhaul, and heterogeneous QoS. The UAV-BS tends to increase its altitude as the coverage constraint increases. Moreover, the backhaul constraint forces the UAV-BS's trajectory closer to the GBS. Lastly, UAV-BS takes into account different QoS requirements of users as much as possible. UAV-BS maximizes the total transmission rate by determining the most suitable trajectory to meet these constraints. © 2022 IEEE
Classification of Breast Lesions on Mammogram Images Using Monarch Butterfly Optimization and Support Vector Machine
No full textCurrently, breast cancer affects many women worldwide. In recent years, many Computer-aided diagnosis (CAD) model have been developed for early diagnosis of breast cancer. An efficient CAD model is suggested to identify mammogram images as benign versus malignant in this study. The suggested CAD model constitutes four stages which are image acgusition, segmentation, feature extraction, feature selection and classification process. Gray level run matrix (GLRM) approach is used for feature extraction, while monarch butterfly optimization (MBO) for feature selection process. Support vector machine (SVM) algorithm is preferred for classification process. The suggested model has been tested on a private mammographic dataset. The suggested model (GLRM+MBO+SVM) shows an 0.944 of accuracy for breast lesion classification. Compared with similar studies, our proposed model showed good classification results for the breast lesion classification process
Antiepileptik İlaçların Romatolojik Yan Etkileri
No full textEpilepsi tedavisinde kullanılan ilaçların yan etki profilleri düşünüldüğünde romatolojik yan etkilerin oldukça kısıtlı bir yer tuttuğu söylenebilir. Literatürde bildirilmiş yan etkiler arasında en sık ilaca bağlı vaskülit ve ilaca bağlı lupus olmakla birlikte artrit, artralji, mukokutanöz döküntüler, otoantikor pozitiflikleri de görülebilmektedir. Bu bölümde ilk olarak ilaca bağlı lupus ile ilaç ilişkili vaskülite değinilecek sonrasında, sık kullanılan antiepileptik ilaçlarla ortaya çıkmış romatolojik yan etkiler tartışılacaktır.Among the side effect profiles of drugs used in the treatment of epilepsy, it can be said that rheumatological side effects have a very limited place. While the most common side effects reported in the literature are drug-induced vasculitis and drug-induced lupus, arthritis, arthralgia, mucocutaneous eruptions, and autoantibody positivity can also be seen. In this section, firstly, drug-induced lupus and drug-related vasculitis and then the rheumatological side effects that occur with frequently used antiepileptic drugs will be discussed
Theoretical Prediction of Two-Dimensional Bc2x (x = N, P, As) Monolayers: Ab Initio Investigations
No full textIn this work, novel two-dimensional BC2X (X = N, P, As) monolayers with X atoms out of the B–C plane, are predicted by means of the density functional theory. The structural, electronic, optical, photocatalytic and thermoelectric properties of the BC2X monolayers have been investigated. Stability evaluation of the BC2X single-layers is carried out by phonon dispersion, ab-initio molecular dynamics (AIMD) simulation, elastic stability, and cohesive energies study. The mechanical properties reveal all monolayers considered are stable and have brittle nature. The band structure calculations using the HSE06 functional reveal that the BC2N, BC2P and BC2As are semiconducting monolayers with indirect bandgaps of 2.68 eV, 1.77 eV and 1.21 eV, respectively. The absorption spectra demonstrate large absorption coefficients of the BC2X monolayers in the ultraviolet range of electromagnetic spectrum. Furthermore, we disclose the BC2N and BC2P monolayers are potentially good candidates for photocatalytic water splitting. The electrical conductivity of BC2X is very small and slightly increases by raising the temperature. Electron doping may yield greater electric productivity of the studied monolayers than hole doping, as indicated by the larger power factor in the n-doped region compared to the p-type region. These results suggest that BC2X (X = N, P, As) monolayers represent a new promising class of 2DMs for electronic, optical and energy conversion systems. © 2022, The Author(s).This work was supported by TUBITAK ULAK-BIM, at the High Performance and Grid Computing Center (TR-Grid e-Infrastructure).This study was funded by National Research Foundation of Korea (No. NRF-2015M2B2A4033123).National Research Foundation of Korea, NRF: NRF-2015M2B2A403312
Investigation of Random Walk Process With Two Barriers and Triangular Interference of Chance
No full textIn this work the process which can be called as “random walk process with two barriers and triangular interference of chance’ is investigated. The main goal of this study is to investigate of the limiting form of the characteristic functions of the ergodic distribution of the processes.This work supported by the Science Development Foundation under the President of the Republic of Azerbaijan - Grant No EIF-ETL-2020-2(36)-16/05/1-M-05
Multimorphological Zinc Oxide: Synthesis and Investigation of Solar Driven Hydrogen Generation and Optoelectrical Properties
No full textThis dissertation is based on a highly distinctive, diosyncratic, and multiversant metal oxide semiconductor, zinc oxide (ZnO). More specifically, the work comprises the utilization of ZnO as both a highly efficient photoanode material and a photoluminescent thin film that serves both energy-based and optoelectronic applications. The emphasis within the scope of the dissertation is made on the morphological diversity of ZnO and the ways to utilize this as an advantage in photoelectrochemical and light-emitting appliances. Essentially, the dissertation consists of three main parts details of which are elaborated as follows; (i) In the first part, ZnO thin films are grown via hydrothermal routes in three diverse morphologies on flexible stainless steel substrates. Here, the aim was to examine the potential of implementation of ZnO-based photoelectrodes into strained, curvature systems by analyzing their photon-to-current conversion efficiencies under flexed conditions. The obtained performances have been correlated with detailed material characterizations offering an integrated vision of the system's operability. (ii) In this part, ZnO thin films were targeted to be grown on specific patterns without engaging costly and time-consuming lithographic techniques. By developing a smart approach, selective growth of ZnO has been attained by taking advantage of its seeding-layer selective nature. To put it differently, knowing that ZnO nanostructures have nucleation and growth pathways that vary strongly depending on the seeding layer, a dual ZnO/Ti stack film has been introduced onto the system. At this stage, Ti was the growth prohibiting agent, while ZnO seeding layer beneath played the role of growth provider. Through the careful utilization of a nanosecond fiber laser system, Ti layers have been successfully removed from the predetermined regions, consequently providing the selective allocation of ZnO nanostructures. By altering the ablation power, a concurrent growth of two different structures has been provided within the same hydrothermal solution and on the same substrate. This nanostructure duality has severely boosted the photoluminescence (PL) ability of ZnO films outscoring the light-emitting performances of individual nanostructures. (iii) In the final part of the dissertation, dual ZnO nanostructured films have been deposited with 0D and 3D inorganic halide perovskite (IHP) layers to maximize the PL performances and prolong the minority carrier lifetimes for future light-emitting device applications. With the incorporation of IHP layers a substantial improvement in emission, especially within the visible range, has been observed. Moreover, the increased carrier lifetimes have shown the promising characteristics of patterned and IHP sensitized multi-morphological ZnO films.Bu tez, kendine özgü özelliklere sahip, çok yönlü bir metal oksit yarı iletken olan çinko oksit'in (ZnO) fotoelektrokimyasal ve optoelektronik alanlara uygulanmasına dayanmaktadır. Başka bir deyişle, çalışma, ZnO'nun hem yüksek verimli bir fotoanot materyali olarak enerji tabanlı uygulamalarda yer almasını hem de optoelektronik uygulamalara hizmet eden yüksek ışıma performansına sahip bir ince film olarak kullanımını içermektedir. Tez kapsamında ZnO'nun morfolojik çeşitliliği ve bu çeşitliliğin farklı uygulamalarda kullanımının avantajları üzerinde durulmuştur. Temel olarak tez, detayları aşağıda belirtilen üç ana bölümden oluşmaktadır; (i) İlk bölümde, ZnO ince filmler, esnek paslanmaz çelik alttaşlar üzerinde üç farklı morfolojide hidrotermal yolla büyütülmüştür. Burada amaç, esnek koşullar altında foton-akım dönüşüm verimliliklerini analiz ederek, ZnO bazlı fotoelektrotların gergin, eğrilik sistemlerine uygulanma potansiyelini incelemektir. Elde edilen performanslar, sistemin çalışabilirliğine ilişkin entegre bir vizyon sunan ayrıntılı malzeme karakterizasyonları ile ilişkilendirilmiştir. (ii) Bu bölümde, ZnO ince filmlerin, maliyetli ve zaman alıcı litografik teknikler kullanılmadan belirli desenler üzerinde büyütülmesi hedeflenmiştir. Akıllı bir yaklaşım geliştirerek, tohum katmanı seçici yapısından yararlanarak ZnO'nun seçici büyümesi sağlanmıştır. Başka bir deyişle, ZnO nanoyapılarının tohumlama katmanına bağlı olarak büyük ölçüde değişen çekirdeklenme ve büyüme yollarına sahip olduğunu bilerek, sisteme bir çift ZnO/Ti yığın filmi eklenmiştir. Bu aşamada Ti büyümeyi engelleyen ajan iken, alttaki ZnO tohum tabakası büyüme sağlayıcı rolünü oynadı. Nanosaniye fiber lazer sisteminin dikkatli kullanımı sayesinde, Ti katmanları önceden belirlenmiş bölgelerden başarıyla çıkarıldı ve sonuç olarak ZnO nanoyapılarının seçici tahsisi sağlanmıştır. Ablasyon gücü değiştirilerek, aynı hidrotermal solüsyon içerisinde ve aynı substrat üzerinde iki farklı yapının aynı anda büyümesi sağlanmıştır. Bu nanoyapı ikiliği, ZnO filmlerinin fotolüminesans (PL) yeteneğini, bireysel nanoyapıların ışık yayma performanslarını geride bırakarak ciddi şekilde artırdı. (iii) Tezin son bölümünde, gelecekteki ışık yayan cihaz uygulamaları için PL performanslarını en üst düzeye çıkarmak ve azınlık taşıyıcı ömürlerini uzatmak için 0D ve 3D inorganik halojenür perovskit (IHP) katmanları ile çift ZnO nanoyapılı filmler biriktirildi. IHP katmanlarının dahil edilmesiyle, özellikle görünür aralıkta emisyonda önemli bir gelişme gözlemlendi. Ayrıca, artan taşıyıcı ömürleri, desenli ve IHP'ye duyarlı hale getirilmiş çok morfolojik ZnO filmlerinin umut verici özelliklerini göstermiştir
Structure and Fragment in Architectural Practice: a Case Study of Mimar Sinan Grand Award Laureates
No full textGeçen yüzyılın son yıllarından bu yana, imge üretimi diğer çağlarda olduğundan daha hızlı arttı. Bunun sonucunda görsel kültür ortamı hiç olmadığı kadar baskın hale geldi ve mimari pratikleri de etkiledi. Bir fikirle başlayan ve bir ürünle biten doğrusal süreç ortadan kalktı. Bu tez, mimari pratiğin süreçlerini ve ürünlerini anlamak için yeni bir yol araştırır. "Fragman" ve "kurgu" olmak üzere iki kavram tanımlar ve bunların ilişkilerini araştırır. Her imge hem bir kurgu hem de bir fragmandır. Fragmanlar, diğer fragmanlar ile ilişkilenerek çeşitli kurgular oluştururken, bu kurgular sonsuz biçimde çeşitli fragmanlara bölünür. Fragman ve kurguların etkileşimi, çıktılarını daha zengin, daha işbirlikçi, daha diyalojik hale getirmektedir. Böylelikle günümüz mimarlık pratiğini nesne ve imgeleriyle anlamak ve yorumlamak için daha geniş bir bakış açısı sağlarlar. Bu tezin odaklandığı fragman ile kurgu arasındaki ilişki, tarafların iletişim kurarken kendilerini korudukları, fragman ve kurgunun kısmi-bütün ilişkisine sahip olduğu bir tür diyalog değildir. Bunun yerine, bu tez, sonsuz bir etkileşim içinde kendini her defasında yeniden kuran, fragman ve kurgunun entelektüel çıktılarına odaklanmaktadır. Bu çıktıların odağında bu tez kapsamında Mimar Sinan Büyük Ödülü yer almaktadır. Ödülü bir mimarın ve pratiğinin temsil eden bir kurgu olarak ele alan bu tez, bu temsiliyetin fragmanlarını araştırır. Tezin uygulamalar kısmındaki çalışmalar tezin kuramsal örgüsünü tamamlayacak şekilde gerçekleştirilmiş olup, bu çalışmalarda, fotoğraflar, röportaj ve söyleşi videoları ve bunlardan üretilen haritalama çalışmaları kullanılmıştır. Sonuç bölümünde ise teorik bölüm çerçevesinde Mimar Sinan Büyük Ödülü'nün imgesi ve kurduğu mimar imgelerine ve fragmanlarına yönelik bir tartışma hedeflenmiştir.Since the last decades of the previous century, image production has increased more rapidly than in any other history phase. The visual culture environment has become dominant and affected architectural practices. The linear process that begins with an idea and ends with an end-product has disappeared. This thesis explores an alternative way of looking at the architectural practice and understanding its processes and products. By defining two concepts, "fragment" and "structure," and questioning their relationship as a pair, this thesis argues that; each image is both a structure and a fragment. Fragments establish various structures by associating with other fragments, while the structures break down into various fragments that go forever. This thesis argues that fragments and structures are rhizomatically related. Through mutual engagement and responsiveness, the communication of the fragments and the structure becomes richer, more cooperative, and more dialogical. Thus, their analysis provides a broader perspective to comprehend and interpret the present day's architectural practice through its objects and images. This thesis focuses on a dialog between fragments and structures that is neither a dialogue between parties who preserve themselves nor a part-whole relationship. Instead, it concentrates on the intellectual outputs of structures and fragments that construct and reconstruct themselves in dialogic relation. As its case studies, this thesis primarily focuses on the practices of Mimar Sinan Grand Award laureates. It describes the award as a structure on its own, interpreting its fragments through its representations. In the case study part of the thesis, the studies were carried out to clarify and exemplify the theoretical discussion. Photographs, interviews, videos, and textual sources are surveyed, and rhizome maps of the architectural practices of each Mimar Sinan Award laureates are created based on this research. As a result, fragments of the practice of each architect and their representations as the award laureates are examined and discussed
Investigation of Humoral and Cellular Immunity in Tobb Etu Hospital Workers After Three Doses of Coronavac Vaccination and After One Dose of Comirnaty Vaccination Following Two Doses of Coronavac
No full textThe Coronavirus disease 2019 (COVID-19) pandemic still continues around the world by making peaks with different variants. In the fight against COVID-19, vaccination is currently the only protective measure. In Turkey, vaccination started firstly in healthcare workers on 13 January 2021 with the CoronaVac (Sinovac Biotech, Chinese) vaccine, and booster doses were administered with the CoronaVac and Comirnaty vaccines in July 2021. In this cross-sectional study, it was aimed to determine the humoral and cellular immunity levels of the employees of the TOBB ETU Hospital 2.5-3.5 months after three doses of vaccination and identify the effective factors. With the power analysis that was conducted with the G*Power software, it was determined to be suitable to include 40 TOBB ETU Hospital workers who had their third dose with the CoronaVac vaccine and 60 workers of the same hospital who had their third dose with the Comirnaty (Pfizer Biontech, Germany) vaccine, and age- and sex-matching was considered by selecting 60 workers randomly from among 223 workers who had Comirnaty as their third dose. The study excluded individuals who had a previous COVID-19 infection or had a positive PCR test result. After collecting blood samples on 18-22 October 2021, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) immunoglobulin G levels were studied with the chemiluminescence immunoassay method using a Beckman-Access device (Beckman Coulter Inc., CA, USA) for humoral immunity, and T-SPOT test (T-SPOT. CO VID SARS-CoV-2 test-Oxford Immunotec, Singapur) was carried out for cellular immunity. Additionally, demographic data, habits, personal information such as weight and height, reasons for choosing the vaccine and post-vaccine side effects were obtained through the data collection form. Data collection was completed on 29 November 2021. As a result, among the healthcare workers who had received their third dose of vaccine with Comirnaty and CoronaVac; while 25% of those who received three doses of CoronaVac had humoral immunity, 93.3% humoral immunity was determined in the heterogeneous vaccine group with two doses of CoronaVac and one dose of Comirnaty vaccine (p 0.05). Cellular immunity was found to be higher (88.3%, 70%) in those who received the heterologous vaccine than those who completed three doses of the same vaccine (p 0.05). In the heterogeneous vaccination group consisting of the healthcare workers who had their third vaccine dose with Comirnaty and those who had it with CoronaVac, humoral and cellular immunity levels were found high. Among the participants whose humoral immunity was found negative, cellular immunity was present in 75% of those who had Comirnaty as their third dose and 63.3% of those who had CoronaVac. While no significant relationship was found between immunity levels and age, sex or body mass index (BMI), the levels of both forms of immunity were lower in those who had chronic diseases. Among the participants, physicians preferred the third dose of Comirnaty vaccine at a rate of 71.4% and laboratory workers preferred this vaccine at a rate of 80% according to the workplace. In the third dose vaccine preference reasons, it was stated that 55% would continue with the same vaccine, experience fewer side effects, 44% provide more immunity and 9% do not prevent going abroad. The incidence of side effects after the third dose of vaccine was 53% higher in those who received the Comirnaty vaccine than in those who received CoronaVac (35%). Based on these data, it was concluded that heterologous vaccination should be preferred in vaccination strategies, and knowing cellular immunity levels is important for the decision. There is a need for more comprehensive and follow-up studies on how long humoral and especially cellular immunity lasts
Diophantine Equations Related With Linear Binary Recurrences
No full textIn this paper we find all solutions of four kinds of the Dio-phantine equations x(2) +/- V(t)xy - y(2) +/- x = 0 and x(2) +/- V(t)xy - y(2) +/- y = 0, for an odd number t, and, x(2) +/- V(t)xy + y(2) - x = 0 and x(2) +/- V(t)xy +/- y(2) - y = 0, for an even number t, where V-n is a generalized Lucas number. This paper continues and extends a previous work of Bahramian and Daghigh