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Ruthenium and Platinum-Modified Titanium Dioxide Support for Nabh4 Hydrolysis
No full textHighly stable platinum (Pt) and ruthenium (Ru)-based catalysts on titanium oxide (TiO2) nanoparticle support were prepared. The productivity of hydrogen generation from sodium borohydride (NaBH4) hydrolysis was observed to be as high as 95%. The activation energies for the hydrolysis reaction in the presence of Ru/TiO2 in aqueous and alkaline solutions were 62.00 and 64.65 kJ mol(-1), respectively. On the other hand, the activation energy value of the hydrolysis reaction with the Pt/TiO2 catalyst decreased from 60.5 to 53.2 kJ mol(-1), and the solution was changed from an aqueous to an alkaline medium. The experimental results have indicated that NaOH concentration (ranging from 0.5 to 2 M) affected the hydrogen generation rate (HGR) differently for both metals on the TiO2 support. Consequently, the HGR of the hydrolysis reaction in the presence of the Ru/TiO2 catalyst decreased with increasing NaOH concentration, whereas the Pt/TiO2 catalyst efficiency increased with increasing NaOH concentration.This work was supported by the Belarusian Republican Foundation for Basic Research (project no. T19TYuB-004) and the Council for Scientific and Technological Research of Turkey (TUBITAK) (project no. 119M030).Belarusian Republican Foundation for Basic Research [T19TYuB-004]; Council for Scientific and Technological Research of Turkey (TUBITAK) [119M030
Robust Shape Optimization Under Model Uncertainty of an Aircraft Wing Using Proper Orthogonal Decomposition and Inductive Design Exploration Method
No full textRobust aerodynamic shape optimization of aircraft components is a computationally expensive process due to a high number of parametrized design variables of complex geometry definitions especially when uncertainties are involved. Therefore, reducing the number of design variables and complexity has vital importance to respond over a range of on-design requirements with the need to meet design constraints in the robust optimization process. In this study, the Proper Orthogonal Decomposition (POD) method is incorporated into the Inductive Design Exploration Method (IDEM) for the aerodynamic shape optimization process of an aircraft wing with reduced computational effort. POD data reduction technique is utilized to filter design variables of the wing by extracting the dominant features of the system to reduce the number of design variables in the robust optimization process. POD-based Radial Basis Function (RBF) data estimation surrogate model is also implemented to enrich design alternatives for the optimization framework with a reduced computational cost. Model uncertainties due to the Computational Fluid Dynamics (CFD) turbulence model are introduced to IDEM as epistemic uncertainties using the eigenspace perturbation methodology. The results of the case study show that the proposed IDEM can obtain robust wing designs satisfying the performance goals while accounting for the uncertainties in the top-to-bottom approach
Determinant Evaluation of Banded Toeplitz Matrices Via Bivariate Polynomial Families
No full textWe define three kinds banded Toeplitz matrices via with the upper and lower bandwidths -/+ x and -/+ y. The determinant evaluation is explicitly given for three kinds banded Toeplitz matrices via bivariate Tribonacci and Delannoy polynomials by using generating function approach and recurrence relations. Moreover perturbed versions of each kinds of the banded Toeplitz matrices by a 2 x 2 general square matrix at the upper right corner will be explicitly computed.Kuwait University Research [SM01/21]This work was supported and funded by Kuwait University Research Grant No. [SM01/21] . We would like to thank anonymous reviewers for their careful reading of our manuscript and their insightful comments
Cross-Disciplinary Pedagogies: Education on Heritage and Climate Change in Europe
No full textCultural heritage in Europe, as well as worldwide, is threatened by climate change, which impairs its integrity and threatens its values. Climate change's effects on heritage must be an integral part of architectural education. There is a complex relationship between climate change and cultural heritage. This research shows a disparity between research, education and practice. The Education for Climate-Resilient European Heritage Architecture project addresses the gaps. It aims to constitute the knowledge between education and research recommended by the 2018 European Union modernization agenda. Multi-disciplinary experts and students from different European Higher Education Institutions have collaborated to formulate an innovative e-learning course and methodology focusing on developing climate resilience for European cultural heritage. Cross-disciplinary Pedagogies aimed to specify and assess current approaches, interpretations and mediums in cross-disciplinary studies addressing heritage and climate change
A Novel Transfer Learning Framework for Chatter Detection Using Convolutional Neural Networks
No full textDetection and avoidance of regenerative chatter play a crucial role in ensuring the high quality and efficiency of machining operations. Predominant analytical approaches provide stability lobe diagrams for machining processes. Deep learning is a general term given to the most recent and successful group of machine learning methods that proved great promise in many areas of human life. This study purposes a novel transfer learning framework that combines analytical solutions and convolution neural network (CNN) under a novel transfer learning framework. Stability lobes and numerical time-domain solutions of analytical methods are used to train and label, arguably one of the most successful CNN architectures, AlexNet. This approach eliminates the need for a time-consuming and costly experimental data collection phase for training. Furthermore, an ensemble empirical mode decomposition based signal pre-processing method is developed. An IMF-based multi-band ensemble approach is proposed where only intrinsic mode functions relevant to each modal frequency of the system are selected based on their entropy increase and used in training multiple AlexNet instances. The measured data were collected during shoulder milling from a CNC-vertical milling machine. The results revealed considerable success in several scenarios ranging from 82 to 100%, without using any experimentally measured data in training. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTAK: 118M414The authors are thankful to Prof. Dr. Yusuf Altıntaş for his support in the dynamic characterization of the CNC-machine tool. This project is supported by TUBITAK (The Scientific and Technological Research Council of Turkey) 1001 program (No. 118M414)
A New Polar-Domain Dictionary Design for the Near-Field Region of Extremely Large Aperture Arrays
No full text9th IEEE International Workshop on Computational Advances in Multi-Sensor Adaptive Processing, CAMSAP 2023 -- 10 December 2023 through 13 December 2023 -- 196947A grid of orthogonal beams with zero column coherence can be easily constructed to cover all prospective user equipments (UEs) in the far-field region of a multiple-antenna base station (BS). However, when the BS is equipped with an extremely large aperture array, the Fraunhofer distance is huge, causing the UEs to be located in the radiative near-field region. This calls for designing a grid of beams based on a near-field dictionary. In the previous work, a polar-domain grid design was proposed to maintain control over the column coherence. A limitation of this approach is identified in this paper, and we propose an enhanced methodology for the design of a polar-domain dictionary specifically tailored for the near-field of an extremely large aperture uniform planar array. Through simulation results, it is demonstrated that the proposed dictionary, employing a non-uniform distance sampling approach, achieves lower column coherence than the benchmark and significantly improves the local-ization of UEs compared to uniform distance sampling. © 2023 IEEE.Stiftelsen för Strategisk Forskning, SS
Clinicopathology of Papillary Thyroid Microcarcinomas
No full textObjective: The widespread use of ultrasonography is the main reason for the increase in the detection of papillary thyroid microcarcinomas (PTMs). We evaluated the clinicopathological features of cases diagnosed with PTM in our clinic. Materials and Methods: In this retrospective study, 354 cases were evaluated. Cytological diagnoses were classified using the 2017 Bethesda System. Statistical analyses were made using IBM SPSS Statistics v. 22. Comparisons between the groups were analyzed with the chi-Square test, Fisher exact chi-square test, Student's t-test, and Mann-Whitney U test. Results: Forty-eight percent of the cases were diagnosed with PTM and 47.1% with incidental papillary thyroid microcarcinoma (IPTM). The rate of female patients was higher in the IPTM group than in the papillary thyroid carcinoma (PTC) group, and the difference was statistically significant (p0.001). The co -occurrence of chronic lymphocytic thyroiditis (CLT) was higher in the PTM cases than in the PTC group (41.2% and 36.9%, respectively). The mean TSH value was higher in the PTM group than in the PTC group. Capsular invasion was seen at a higher rate in the PTC group than in the PTM group (p0.001). Conclusion: In our study, we observed lower TSH values in cases with IPTM compared to those with PTC at a younger age and in the female gender. We consider that due to the small tumor diameter of IPTMs, their metastasis ability is lower, and therefore they have a good prognosis
Exploring the Impact of Training Datasets on Turkish Stance Detection
No full textStance detection has garnered considerable attention from researchers due to its broad range of applications, including fact-checking and social computing. While state-of-the-art stance detection models are usually based on supervised machine learning methods, their effectiveness is heavily reliant on the quality of training data. This problem is more prevalent in stance detection task because the stance of a text is intimately tied to the target under consideration. While numerous datasets exist for stance detection, determining their suitability for a specific target can be challenging. In this work, we focus on Turkish stance detection and explore the impact of training data on the model performance. In particular, we fine-tune BERT model with various datasets and assess their performance when the test data is the same/different compared to the training data in terms of target and domain. In addition, given the scarcity of resources for Turkish stance detection, we investigate i) whether we can use existing datasets in other languages in a cross-lingual setup, and ii) the effectiveness of data augmentation with simple automatic labeling methods. In order to conduct our experiments, we also create new Turkish stance detection datasets for various targets in different domains. In our comprehensive experiments, our findings are as follows. 1) Using training data with multiple targets in the same domain yields high performance as the model is able to learn more characteristics of expressing stance with additional data. 2) The domain of the training data plays a crucial role in achieving high performance. 3) Automatically generated data enhances performance when combined with manually annotated data. 4) Training solely on Turkish data outperforms training with the combination of Turkish and English data. Overall, our study points out the importance of creating Turkish annotated datasets for different domains to achieve high performance in stance detection
Buildings That Are Part of Nature; a Study of the Relationship Between Architecture and Nature Through the Cases of Buildings
No full textUncontrolled urbanization and the resulting conflict with nature have led to global issues affecting the entire world and ecosystem. Climate crises, depletion of natural resources, and disruption of ecological balance are among the primary problems. While humans play a significant role in the emergence of these problems, architecture has become a crucial profession in preserving ecological balance. Innovative, sustainable attitudes, and approaches towards environmental and climate issues need to be developed through architecture. Just as nature offers unlimited possibilities to humans, buildings and people are also expected to provide unlimited opportunities to nature. It is of great importance that future generations efficiently utilize the opportunities offered by nature while producing built environments. When closely examined, the claim that buildings labeled as green or sustainable are in harmony with nature can be questionable. This thesis aims not only to explore self-sufficient buildings but also to investigate how buildings can be truly designed to be in harmony with nature and possess qualities that are in symbiosis with it. Initially, a conceptual framework encompassing ecological psychology, ecological architecture, and regenerative architecture will be discussed to explore the relationships between buildings and nature. Through these readings, the mutual interaction and exchange that should exist between buildings and nature will be revealed, and research will focus on how buildings should not just adapt to nature but coexist with it. In the continuation of the study, it is important not only to address this conceptual framework but also to examine current practices. Frequently used green building certification systems, awards, and principles will be scrutinized to evaluate whether they serve merely as a 'marketing tool' or if they genuinely provide adequate scope for evaluating buildings as integrated with nature. Based on all these readings and analyses, the developed holistic approach aims to define the qualities that a nature-integrated building should possess. Buildings with green building certification and those labeled as green/ecological/regenerative without certification will be selected. They will be evaluated and interpreted using the created holistic approach: the Nature-Integrated Building Evaluation Approach. Consequently, an inference will be made as to whether the buildings currently designated as sustainable/green/ecological are a part of nature, and their deficiencies will be highlighted, emphasizing the crucial role that nature should play in future architectural endeavors. This study aims to foster the adoption of a more solution-oriented and sustainable approach to global environmental problems, encouraging the design of built environments as structures that are not only integrated with nature but also have a positive impact on the environment. The integration of technological advancements and tools with environmental awareness will ease the process of designing buildings that not only emphasize eco-friendliness but also make a favorable impact on the environment.Kontrolsüz kentleşme ve doğa arasındaki çatışma sonucunda tüm dünyayı ve ekosistemi etkileyen sorunlar ortaya çıkmaktadır. İklim krizleri, doğal kaynakların yok olması ve ekolojik dengenin bozulması başlıca sorunlar arasında yer almaktadır. Bu sorunların ortaya çıkmasında insanlar büyük rol oynarken; mimarlık ise ekolojik dengenin korunmasında önemli bir meslek haline gelmektedir. Çevre ve iklim sorunlarına karşı yenilikçi, sürdürülebilir tutum ve yaklaşımların mimarlık aracılığıyla geliştirilmesi gerekmektedir. Doğa insanlara sınırsız olanaklar sunarken aynı şekilde binaların ve insanların da doğaya sınırsız olanaklar sağlaması beklenmektedir. Gelecek nesillerin yapılı çevreler üretirken doğanın sunduğu imkanları en verimli şekilde kullanması büyük önem taşımaktadır. Günümüzde yeşil veya sürdürülebilir bina olarak nitelendirilen yapıların doğa ile iç içe olduğu iddiası yakından incelendiğinde sorgulanabilir bir hal almaktadır. Bu tez sadece kendi kendine yeten binaların değil, gerçek anlamda doğa ile iç içe olan binaların nasıl tasarlanabileceği ve hangi niteliklere sahip olması gerektiğini araştırmayı hedeflemektedir. İlk olarak, binalar ve doğa arasındaki ilişkileri keşfetmek için ekolojik psikoloji, ekolojik mimari ve rejeneratif mimariyi içeren kavramsal çerçeve tartışılacaktır. Bu okumalar sayesinde bina ve doğa arasında olması gereken karşılıklı etkileşim ve değişim ortaya çıkarılacaktır, binaların doğaya adapte olması değil, doğa ile hemhal olması üzerine araştırmalar yapılacaktır. Çalışmanın devamında, sadece bu kavramsal çerçevenin ele alınması değil, aynı zamanda mevcut uygulamaların da incelenmesi önemlidir. Günümüzde sıkça kullanılan yeşil bina sertifikasyon sistemleri, ödüller ve prensipleri incelenecek; bu sistemlerin sadece bir "pazarlama aracı" mı yoksa gerçekten doğayla bütünleşik binaların değerlendirilmesinde yeterli kapsamı sağlayıp sağlamadığı değerlendirilecektir. Tüm bu okumalar ve analizler temelinde geliştirilen bütünsel yaklaşım, doğayla bütünleşen bir binanın sahip olması gereken nitelikleri tanımlamayı amaçlamaktadır. Yeşil bina sertifikasına sahip olan ve sertifikasız ancak yeşil/ekolojik/rejeneratif olarak etiketlenen binalar seçilecek ve oluşturulan "Doğayla Bütünleşik Bina Değerlendirme Yaklaşımı" kullanılarak değerlendirilip yorumlanacaktır. Sonuçta, mevcut olarak sürdürülebilir/yeşil/ekolojik olarak nitelendirilen binaların doğanın bir parçası olup olmadığına dair bir sonuca varılacak ve çıkarımlarda bulunulacaktır. Bu çalışma ile gelecekte yapılacak mimarlık çalışmalarının, çevre ile uyumlu ve doğayı destekleyen bir yaklaşımı benimsemesi böylece küresel çevre sorunlarına karşı çözümcül bir bakış açısı geliştirilmesi istenmiştir. Teknolojik yeniliklerin ve araçların çevresel bilinç ile harmanlanması, binaların sadece çevre dostu değil, aynı zamanda çevreye olumlu katkı sağlayan yapılar olarak tasarlanmasını sağlayacaktır