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On the fracture of nano-silica/epoxy bonded single-lap steel joints
No full textT his research aims to investigate the influence of nano-silica inclusion on the adhesive properties of an epoxy resin, and its capability in increasing the failure load of the joint with steel substrates. For this purpose, single-lap joints manufactured from Stainless Steel 304 (SS) adherends bonded together with a thin layer of the silica-reinforced epoxy resin (as the adhesive) are investigated. To improve the epoxy, silica nanoparticles (SNPs) are utilized in three different concentrations (i.e. 1, 2 and 3 wt. %). Failure loads of the joints are extracted by uniaxial tensile loading for the joints including either neat or reinforced epoxy resins. Scanning Electron Microscope (SEM) are used to examine the dispersion quality of nanoparticles into the polymer as well as the hindrance effect of the nano-silica inclusions on the micro-cracks’ propagation or/and their unification. In addition, the fracture surfaces of the joints were investigated so as to relieve the failure type of the joints; whether cohesive or a combination of both adhesive and cohesive types. It was found out that the joint including silica-reinforced epoxy resin at 2wt.% best improved the failure load and changed the debonding mechanism to a fully cohesive type compared to that of the joint comprising the neat resin
Destinasyon Markalamada Dijital Hikâye Anlatımı: Göbeklitepe Örneği
No full textGünümüzde hikâye anlatımı markalar açısından ön plana çıkan bir uygulamadır. Özellikle teknolojik gelişmelerle anlatıma zenginlik katan teknikler sunan dijital hikâye anlatımı günümüzde sıkça kullanılmaktadır. Dijital hikâye anlatımı destinasyon markalama bağlamında önemli imkanlar sunmaktadır. Bu çalışmada, 2018 yılında UNESCO Dünya Miras Listesi’ne alınan Göbeklitepe’ye ilişkin destinasyon markalamada dijital hikâye anlatımının kullanımı ele alınmaktadır. Bu bağlamda “Göbeklitepe: Zero Point in Time” tanıtım filmi göstergebilimsel çözümleme yöntemi aracılığıyla incelenmiştir. Ayrıca film dijital hikâye anlatımının bileşenleri bağlamında değerlendirilmiştir. Dijital hikâye anlatımında, hayvanlara ilişkin kültleşme sürecine ve Göbeklitepe’deki ritüel kökenli toplantılar bağlamında bu hayvanların önemine hayvan kabartmalarına/figürlerine yapılan yakın çekimlerle sıkça gönderme yapılmaktadır. Dijital hikâye anlatımında Göbeklitepe’nin ve inancın medeniyete giden yolun başına, tarihin sıfır noktasına konumlandırılması hem sözel hem de görsel unsurlarla gerekçelendirilerek (Göbeklitepe’nin inşa süreci, yapıdaki hayvan kabartmaları/figürleri, totem benzeri yapılar ve megalitler) izleyicilere aktarılmaktadır. Göbeklitepe’ye ilişkin destinasyon markalamada aktarılan hikâyenin gücü, dijital hikâye anlatımının bileşenlerinin (bakış açısı, çarpıcı bir soru, duygusal içerik, seslendirme yeteneği, müziğin gücü, yalın içerik ve ilerleme hızı) etkin kullanımı yoluyla, artmaktadır
Noma Tabanlı Çoklu Erişimde Kullanıcı Çizelgeleme ve Yol Atama Tekniklerinin Geliştirilmesi
No full textIn wireless communications, user nodes in networks require techniques to transfer a high load of packets to each other in a limited time frame. Non-orthogonal Multiple Access (NOMA) and Successive Interference Cancellation (SIC) are such techniques. In addition to that, Q-learning is a new method of machine learning that can be used to analyze the success communication planning and transfer of packets. According to the simulation results, integrating Q-learning has increased the number of transferred packets the most. Scheduling and multi-path routing for system output optimization has been studied for wireless networks. According to the literature reviews, our model differs from others by applying NOMA (Non-orthogonal Multiple Access) at the transmitters and SIC (Successive Interference Cancellation) at the receviers. We assume that the transmission powers are constant. NOMA (one transmitter, two receivers), SIC (two transmitters, one receiver) and single links (one transmitter and one receiver) are formed. Links have been scheduled to optimize the weighted sum of end to end flow rate. The improvement in performance has been tested by the integration of NOMA and SIC to the system. Numerical results show that NOMA and SIC improves the system wieghted sum rate by 25-30%. A case where the source of all flows is the same has been investigated. In this scenario, NOMA has provided 65-70% improvement in performance whereas SIC has shown no effect on the performance. In a distributed ad hoc network where SIC is integrated, joint optimal routing and minimum length scheduling is studied. Optimal solution finds minimum amount of time slots required to schedule transmissions at a given flow rate in an SIC network. The performance of the optimal solution with SIC is compared to the one without SIC. According to the results, the optimal solution using SIC shows a significiant improvement compared to the one that does not use SIC.Kablosuz haberleşmede, ağlarda kullanıcı düğümlerin birbirlerine iletim yapabilmelerini, belirli sürede çok sayıda paketin iletilmesini sağlayacak yöntemlerin geliştirilmesi incelenmiştir. Dik Olmayan Çoklu Erişim (NOMA) ve Ardışık Girişim Çıkarımı (SIC) ağlarda kullanımına yeni bir makine öğrenmesi yöntemi olan Q-öğrenmenin dahil edilmesi ile kullanıcılar arasındaki iletişimin verimliliğinin analizi yapılmıştır. Sonuçlara göre, Q-öğrenmenin kullanıldığı yöntem en çok paket sayısını iletmeyi başarmıştır. Kablosuz ağlarda sistem çıktısı optimizasyonu için çizelgeleme ve çok-yollu yönlendirme çalışılmıştır. Literatürdeki çalışmalardan farklı olarak, modelimiz, iletici düğümlerin güç alanında Dikgen Olmayan Çoklu Erişim (Non-Orthogonal Multiple Access- NOMA) ile çoklama yapmakta ve de alıcılarda Ardışık Girişim Çıkarımı (Successive Interference Cancellation- SIC) kullanarak iletimlerin gerçekleşmesini sağlamaktadır. Düğümlerin iletim güçlerinin sabit olduğu varsayılmıştır. NOMA (bir iletici ve iki alıcı) ya da SIC (iki iletici ve bir alıcı) uygulayabilen üç düğümlü birleşik bağlara ek olarak tek bağlar (bir iletici ve bir alıcı) oluşturulmuştur. Bağlar, uçtan uca akış hızlarının ağırlıklı toplamının optimizasyonu için zamanda çakışmayacak şekilde çizelgelenmiştir. Başarımdaki gelişme, NOMA ve SIC eklenerek test edilmiştir. Sayısal sonuçlar, NOMA ve SIC ile ağırlıklı toplam hızda neredeyse eşit ve belirgin iyileşme (25-30%) olduğunu göstermektedir. Tüm akışların kaynağının aynı olduğu bir durum incelenmiştir. Bu durumda, NOMA'nın kullanılması 65-70% iyileşme sağlamış, SIC'nin kullanılması etkisiz olmuştur. Son olarak, Ardışık Girişim Çıkarımı (Successive Interference Cancellation- SIC) tabanlı dağıtık kablosuz tasarsız bir ağda birleşik optimal yönlendirme ve en kısa sürede çizelgeleme çalışılmıştır. En iyi çözüm, SIC kullanılan bir ağda, verilen bir akış hızında, çizelgeleme için gereken en az zaman dilimi sayısını bulmaktadır. SIC kullanan optimal çözümün performansı, girişimin gürültü olarak kullanıldığı durumla karşılaştırılmaktadır. Sonuçlara göre, SIC kullanan optimal çözüm, SIC kullanmayan optimal çözümün performansına kıyasla daha belirgin bir iyileşme göstermiştir
Demonstration of the Decrease in Locomotor Activity and Central Nervous System in the Demyelination Model, in Which the Toxic Agent Is Realized by Gavage
No full textIntroduction: The cuprizone model is a well-established instance to study demyelination and remyelination in rodents. The primary aim of this study was to demonstrate the loss of function in motor activity. Second, it was evaluated together with the changes in the amount of myelin in the ongoing process. Materials and Methods: This study is based on the administration of the cuprizone model in male C57BL/6 mice by oral gavage. The advantage of the oral gavage model is that mice were subjected to the equal dose of cuprizone. For this reason, the nonequal in demyelination was minimized. We have designed four groups, including demyelination/control and remyelination/control. Results: The results of the walking test and open field test showed that locomotor activity in the demyelination group deteriorated. Increased glial fibrillary acidic protein and decreased myelin basic protein expressions were shown in the corpus callosum of the demyelination group compared to the control and remyelination groups. The g-ratio of the demyelination group was calculated 0.86 ± 0.07, the g-ratio of the demyelination control group was calculated 0.66 ± 0.1, the g-ratio of the remyelination group was calculated 0.83 ± 0.06, and the g-ratio of the remyelination control group was calculated 0.76 ± 0.09. Discussion and Conclusion: In conclusion, in this demyelination model, which was applied differently from the literature, in our study, the behavioral effect on motor activity and to what extent it appeared histologically was evaluated. Thus, investigating the loss of function in motor activity as well as histological examination increased the reliability of the model we created in our study. © 2023 Journal of the Anatomical Society of India.Research Projects with project number TYL‑2016‑1552 and a Master of Science thesis of Serra OZTURK.Akdeniz Üniversitesi: TYL‑2016‑1552This study was supported by Akdeniz University Scientifi
Incentives of a Monopolist for Innovation Under Regulatory Threat
No full textThis paper investigates whether a natural monopoly with private cost information can reduce the likelihood of regulatory threat by investing, in the ex-ante stage, in cost-reducing R ;D to generate process innovations and whether such an investment can yield Pareto gains in welfare. We model the regulatory process using a sequential game where a benevolent regulator makes the first move by announcing the probability that the monopolist will be optimally regulated. The monopolist, hearing this announcement, chooses the optimal level of its R ;D investment. We numerically compute the subgame-perfect Nash equilibrium of this game for a wide range of model parameters. Our results show that the monopolist invests more in R ;D if the regulatory threat is less certain. Anticipating this response, the regulator makes her threat less certain if she puts more weight on the monopolist's profit. Moreover, we find that regulation with uncertainty can be Pareto superior to regulation with certainty if the welfare weight of the monopolist is sufficiently, but not extremely, high or if the cost of R ;D is sufficiently small. On the other hand, regulation with uncertainty is not self-enforcing (incentive-compatible for the regulator) if the welfare weight of the monopolist is sufficiently high
Conflicts, Irregular Migration and Turkey’s Security in the Context of Turkey-European Union Relations
No full textDue to its geographical proximity to conflict zones, Turkey has become the target country for asylum seekers and refugees from different countries having diverse ethnic origins. Turkey’s emerging role as a target country became even more problematic due to the outbreak of the Syrian Civil War in 2011, triggered by the Arab Spring. The Syrian conflict not only led to an increased flow of refugees but also destabilized the Turkish borders. In this regard, Turkey has established a set of strategies and transformations to tackle these issues. This paper examines how migration has evolved as a security issue for Turkey in the last four decades, in general. In particular, the study deals with the security-related issues in terms of migration from the Turkish perspective and evaluates the refugee crisis in 2016 and its implications for Turkey and the European Union. The article concludes with reactions to irregular migration and the refugee flow by shedding light on both Turkey and the European Union’s perspectives
Facile and Controlled Synthesis of 2d Organometal Halide Perovskite Pure Ba2mapb2i7 and Heterostructured Ba2pbi4/Ba2mapb2i7 Single Crystals
No full textTwo dimensional (2D) organometal halide perovskites (OHPs) have attracted intensive interest for their diverse optoelectronic applications. However, a practical and controllable solution-based way particularly for the synthesis of pure BA2MAPb2I7 and heterostructured BA2PbI4/BA2MAPb2I7 single crystals, which are of great importance for high performance photodetectors, is still lacking. In this study, we report the efficient synthesis route of large-area high-quality BA2MAPb2I7 and BA2PbI4/BA2MAPb2I7 single crystals. We show that the combined method of solution temperature lowering and limiting reagent approaches yields rapid and controllable synthesis. In addition, the correct determination of the BAI:MAI:PbI2 molarity ratios in the synthesis process was revealed to be highly significant. These results provide fundamental insight and useful guideline for obtaining the presented 2D OHPs with regard to high practicality and controllability
Luminosity Determination in Pp Collisions at √s=13 Tev Using the Atlas Detector at the Lhc
No full textThe luminosity determination for the ATLAS detector at the LHC during Run 2 is presented, with pp collisions at a centre-of-mass energy s=13 TeV. The absolute luminosity scale is determined using van der Meer beam separation scans during dedicated running periods in each year, and extrapolated to the physics data-taking regime using complementary measurements from several luminosity-sensitive detectors. The total uncertainties in the integrated luminosity for each individual year of data-taking range from 0.9% to 1.1%, and are partially correlated between years. After standard data-quality selections, the full Run 2 pp data sample corresponds to an integrated luminosity of 140.1 ± 1.2 fb - 1 , i.e. an uncertainty of 0.83%. A dedicated sample of low-pileup data recorded in 2017–2018 for precision Standard Model physics measurements is analysed separately, and has an integrated luminosity of 338.1 ± 3.1 pb - 1 . © 2023, The Author(s).IN2P3-CNRS; SCI/013; U.S. Department of Energy, USDOE; Alexander von Humboldt-Stiftung, AvH; CRC Health Group, CRC: 21/SCI/017; Canarie; H2020 Marie Skłodowska-Curie Actions, MSCA; Multiple Sclerosis Scientific Research Foundation, MSSRF; CERN; Compute Canada; Göran Gustafssons Stiftelser; Natural Sciences and Engineering Research Council of Canada, NSERC; National Research Council Canada, NRC; Canada Foundation for Innovation, CFI; Science and Technology Facilities Council, STFC; Leverhulme Trust; European Research Council, ERC; European Cooperation in Science and Technology, COST; Australian Research Council, ARC; National Stroke Foundation, NSF; Neurosurgical Research Foundation, NRF; Helmholtz-Gemeinschaft, HGF; Minerva Foundation; Deutsche Forschungsgemeinschaft, DFG; Agence Nationale de la Recherche, ANR; Japan Society for the Promotion of Science, KAKEN; Ministry of Education, Culture, Sports, Science and Technology, MEXT; Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, SNF; Danmarks Grundforskningsfond, DNRF; Fundação de Amparo à Pesquisa do Estado de São Paulo, FAPESP; National Natural Science Foundation of China, NSFC; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT; Fundação para a Ciência e a Tecnologia, FCT; Bundesministerium für Bildung und Forschung, BMBF; Chinese Academy of Sciences, CAS; Austrian Science Fund, FWF; Generalitat de Catalunya; Ministry of Science and Technology of the People's Republic of China, MOST; Agencia Nacional de Promoción Científica y Tecnológica, ANPCyT; Nederlandse Organisatie voor Wetenschappelijk Onderzoek, NWO; Bundesministerium für Wissenschaft, Forschung und Wirtschaft, BMWFW; Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq; Nella and Leon Benoziyo Center for Neurological Diseases, Weizmann Institute of Science; Israel Science Foundation, ISF; Instituto Nazionale di Fisica Nucleare, INFN; Narodowe Centrum Nauki, NCN; Javna Agencija za Raziskovalno Dejavnost RS, ARRS; Ministarstvo Prosvete, Nauke i Tehnološkog Razvoja, MPNTR; Ministerio de Ciencia e Innovación, MICINN; Centre National pour la Recherche Scientifique et Technique, CNRST; Staatssekretariat für Bildung, Forschung und Innovation, SBFI; Horizon 2020; British Columbia Knowledge Development Fund, BCKDF; European Regional Development Fund, ERDF; Defence Science Institute, DSI; Narodowa Agencja Wymiany Akademickiej, NAWA; Institutul de Fizică Atomică, IFA; Agencia Nacional de Investigación y Desarrollo, ANID; Royal Society of South Australia, RSSA; Irish Rugby Football Union, IRF
Critical Decision Making for Rehabilitation of Hydroelectric Power Plants
No full textDue to their diminishing performance, reliability, and maintenance requirements, there has been a rise in the demand for the restoration and renovation of old hydroelectric power facilities in recent decades. Prior to initiating a rehabilitation program, it is crucial to establish a comprehensive understanding of the power plant's current state. Failure to do so may result in unnecessary expenses with minimal or no improvements. This article presents a systematic rehabilitation methodology specifically tailored for Francis turbines, encompassing a methodological approach for condition assessment, performance testing, and evaluation of rehabilitation potential using site measurements and CFD analysis, and a comprehensive decision-making process. To evaluate the off-design performance of the turbines, a series of simulations are conducted for 40 different flow rate and head combinations, generating a hill chart for comprehensive evaluation. Various parameters that significantly impact the critical decision-making process are thoroughly investigated. The validity of the reverse engineering-based CFD methodology is verified, demonstrating a minor difference of 0.41% and 0.40% in efficiency and power, respectively, between the RE runner and actual runner CFD results. The optimal efficiency point is determined at a flow rate of 35.035 m(3)/s, achieving an efficiency of 94.07%, while the design point exhibits an efficiency of 93.27% with a flow rate of 38.6 m(3)/s. Cavitation is observed in the turbine runner, occupying 27% of the blade suction area at 110% loading. The developed rehabilitation methodology equips decision-makers with essential information to prioritize key issues and determine whether a full-scale or component-based rehabilitation program is necessary. By following this systematic approach, hydroelectric power plants can efficiently address the challenges associated with aging Francis turbines and optimize their rehabilitation efforts.European Union/Instrument for Pre Accession Assistance (IPA) Energy Sector Technical Assistance Project Consulting Services for Energy Efficiency in Power GenerationThe authors would like to thank the Republic of Turkey Ministry of Energy and Natural Resources and the World Bank Group for their financial support of the project entitled European Union/Instrument for Pre Accession Assistance (IPA) Energy Sector Technical Assistance Project Consulting Services for Energy Efficiency in Power Generation. The computations presented here were conducted using the computational cluster of the TOBB University Hydro Energy Research Laboratory (TOBB ETU Hydro)