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Effects of Graphene, Carbon Nanotubes and Boron Nitride Nanotubes on Thermal and Mechanical Performances of Poly(vinyl butyral)-Based Composite Nanofibers
No full textAbstract In this study, electrospun poly(vinyl butyral) (PVB)-based composite nanofibers were prepared through the addition of multilayer graphene (MLG), carbon nanotubes (CNT) and boron nitride nanotubes (BNNT) in order to investigate the mechanical and thermophysical properties of the resultant composite nanofibers. Morphological and spectral characterizations confirmed the successful incorporation of the nanofillers in the nanofibers. The tensile testing of the composite nanofibers showed that the tensile strength and Young’s modulus of the composite nanofibers were improved compared to PVB nanofibers. The thermal conductivity coefficients of the PVB/MLG, PVB/CNT and PVB/BNNT nanofibers, respectively, increased to 32.35 ± 1.23 mW/m.K, 30.28 ± 1.45 mW/m.K and 31.63 ± 1.67 mW/m.K, while that of neat PVB nanofibers was measured as 20.52 ± 0.62 mW/m.K. The results pointed out that all three PVB-based composite nanofibers are promising materials for thermal management applications in textiles.https://doi.org/10.1007/s12221-025-01016-
Search for charged-lepton flavor violation in the production and decay of top quarks using trilepton final states in proton-proton collisions at s=13 TeV
No full textA search is performed for charged-lepton flavor violating processes in top quark (<a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>t</a:mi></a:math>) production and decay. The data were collected by the CMS experiment from proton-proton collisions at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mn>138</c:mn><c:mtext> </c:mtext><c:mtext> </c:mtext><c:msup><c:mi>fb</c:mi><c:mrow><c:mo>−</c:mo><c:mn>1</c:mn></c:mrow></c:msup></c:math>. The selected events are required to contain one opposite-sign electron-muon pair, a third charged lepton (electron or muon), and at least one jet of which no more than one is associated with a bottom quark. Boosted decision trees are used to distinguish signal from background, exploiting differences in the kinematics of the final states particles. The data are consistent with the standard model expectation. Upper limits at 95% confidence level are placed in the context of effective field theory on the Wilson coefficients, which range between <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:mrow><e:mn>0.024</e:mn><e:mi>–</e:mi><e:mn>0.424</e:mn><e:mtext> </e:mtext><e:mtext> </e:mtext><e:msup><e:mrow><e:mi>TeV</e:mi></e:mrow><e:mrow><e:mo>−</e:mo><e:mn>2</e:mn></e:mrow></e:msup></e:mrow></e:math> depending on the flavor of the associated light quark and the Lorentz structure of the interaction. These limits are converted to upper limits on branching fractions involving up (charm) quarks, <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"><g:mi>t</g:mi><g:mo stretchy="false">→</g:mo><g:mi>e</g:mi><g:mi>μ</g:mi><g:mi>u</g:mi></g:math> (<j:math xmlns:j="http://www.w3.org/1998/Math/MathML" display="inline"><j:mi>t</j:mi><j:mo stretchy="false">→</j:mo><j:mi>e</j:mi><j:mi>μ</j:mi><j:mi>c</j:mi></j:math>), of <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"><m:mn>0.032</m:mn><m:mo stretchy="false">(</m:mo><m:mn>0.498</m:mn><m:mo stretchy="false">)</m:mo><m:mo>×</m:mo><m:msup><m:mn>10</m:mn><m:mrow><m:mo>−</m:mo><m:mn>6</m:mn></m:mrow></m:msup></m:math>, <q:math xmlns:q="http://www.w3.org/1998/Math/MathML" display="inline"><q:mn>0.022</q:mn><q:mo stretchy="false">(</q:mo><q:mn>0.369</q:mn><q:mo stretchy="false">)</q:mo><q:mo>×</q:mo><q:msup><q:mn>10</q:mn><q:mrow><q:mo>−</q:mo><q:mn>6</q:mn></q:mrow></q:msup></q:math>, and <u:math xmlns:u="http://www.w3.org/1998/Math/MathML" display="inline"><u:mn>0.012</u:mn><u:mo stretchy="false">(</u:mo><u:mn>0.216</u:mn><u:mo stretchy="false">)</u:mo><u:mo>×</u:mo><u:msup><u:mn>10</u:mn><u:mrow><u:mo>−</u:mo><u:mn>6</u:mn></u:mrow></u:msup></u:math> for tensorlike, vectorlike, and scalarlike interactions, respectively.https://doi.org/10.1103/physrevd.111.012009https://hdl.handle.net/20.500.12831/24107https://hdl.handle.net/10281/554667https://doi.org/10.1103/PhysRevD.111.012009https://hdl.handle.net/11486/415
Risk Factors Preventing Ships from Effective Vessel Traffic Services Reporting
No full textThis study aims to identify deficiencies in SP1, SP2, sector zone transit reporting, and emergency reporting within the VTS reporting of ships in the Turkish Straits, uncover the risk factors hindering effective VTS reporting, and propose strategic solutions to improve system efficiency. Methodology: Errors and omissions in SP1, SP2, sector passage, and emergency reporting—stemming from knowledge and experience gaps—were analyzed using the Failure Modes and Effects Analysis (FMEA) method. Nine experts assessed the failure modes, which were categorized based on risk levels: very high, high, and medium. Findings: As a result of FMEA analysis, 5 failure types were determined as very high risk, 6 failure types as high risk and 5 failure types as medium risk. In particular, it was determined that 42.7% of emergency reporting had a very high risk factor. It was determined that these risks were caused by reasons such as lack of situation awareness, lack of knowledge and experience and commercial pressures. In order to improve the reporting processes, training programmes should be developed to increase the level of knowledge of masters, officers, agents and ship operators on the Turkish Straits Maritime Traffic Regulation (TBDTDY) and reporting procedures. In order to overcome communication deficiencies, it is suggested that Standard Maritime Communication Clauses (SMCP) communication patterns should be revised according to the VTS requirements. In addition, it is envisaged that pilot and tug escort should be obligatory for the transit of risky vessels and deterrent administrative sanctions should be imposed on ship operators who violate the reporting procedures. Conclusion: This study offers practical strategic solutions to improve VTS reporting systems in the Turkish Straits, aiming to elevate maritime safety standards and operational efficiency.https://doi.org/10.3233/pmst25006
Capturing Aerodynamic Characteristics of ATTAS Aircraft with Evolving Intelligent System
No full textAccurate modeling of aerodynamic coefficients is crucial for understanding and optimizing the performance of modern aircraft systems. This paper presents the novel deployment of an Evolving Type-2 Quantum Fuzzy Neural Network (eT2QFNN) for modeling the aerodynamic coefficients of the ATTAS aircraft to express the aerodynamic characteristics. eT2QFNN can represent the nonlinear aircraft model by creating multiple linear submodels with its rule-based structure through an incremental learning strategy rather than a traditional batch learning approach. Moreover, it enhances robustness to uncertainties and data noise through its quantum membership functions, as well as its automatic rule-learning and parameter-tuning capabilities. During the estimation of the aerodynamic coefficients via the flight data of the ATTAS, two different studies are conducted in the training phase: one with a large amount of data and the other with a limited amount of data. The results show that the modeling performance of the eT2QFNN is superior in comparison to baseline counterparts. Furthermore, eT2QFNN estimated the aerodynamic model with fewer rules compared to Type-1 fuzzy counterparts. In addition, by applying the Delta method to the proposed approach, the stability and control derivatives of the aircraft are analyzed. The results prove the superiority of the proposed eT2QFNN in representing aerodynamic coefficients.in International Congress on Human-Computer Interaction, Optimization and Robotic Applications, 2025https://doi.org/10.1109/ichora65333.2025.11017134https://dx.doi.org/10.48550/arxiv.2504.19949http://arxiv.org/abs/2504.19949https://doi.org/10.48550/arXiv.2504.1994
Unconventional Gas Potential of Black Shales from Silurian Findikli Formation in northwestern Anatolia, T&amp;#252;rkiye: Characterization of Geochemistry
No full textAs conventional hydrocarbon resources become depleted and theoretical innovations in hydrocarbon exploration advance, unconventional resources have gained substantial attention from researchers and explorers in recent decades. In the global energy consumption structure, unconventional shale gas progressively assumes a crucial role in the overall energy landscape. This research is motivated by the high probability of deriving gas accumulations encountered in drilling on the northwestern Anatolia (Akcakoca area) offshore from Paleozoic-aged rocks. Studied black shales from the Silurian Findikli Formation in the Sakarya region of northwestern Anatolia are one of the alternative unconventional resources.Working with outcrop samples, this work evaluates the unconventional gas potential by performing geochemical characterization of these black shale samples. Studied samples were analyzed by Rock-Eval Pyrolysis. The present-day total organic carbon (TOCpd) contents range from 0.54 to 1.57 wt.%. High Tmax (up to 504oC) and low Hydrogen Index (HI) values (4-38 mg HC/g TOC) indicate that these shales are thermally over-mature and seem to be a spent hydrocarbon source rock. The remaining hydrocarbon generative potential (S1+S2) of 0.06&amp;#8211;0.49 mg HC/g rock also supports this assessment. The recent organic matter type is Type IV kerogen which can yield limited gas products plotting on the H/C versus O/C atomic ratios on the modified Van Krevelen diagram. According to the interpretive of shale gas potential parameters based on Jarvie&amp;#8217;s equation reconstructed these black shales originally may have good to very good source rock potential, with the calculated average original values of TOCo being 1.72 wt.% and HIo is 448 mg HC/g TOC. It can be concluded that the characteristics of studied shales seem to be nearly compatible with those of Utica shales in terms of the hydrocarbon generative potential. The studied black shales have lost 95% of their original hydrocarbon potentials, and seem to be a spent hydrocarbon source rock, indicating good risk for gas. However, the source rock may be very deep and deformed from the past to the present day, considering the paleogeographical location and geological evolution of the study area. Further research is required.Keywords: Unconventional Gas Potential, Source Rock, Geochemical Characteristics, Silurian Black Shales, Northwestern Anatolia (T&amp;#252;rkiye)https://doi.org/10.5194/egusphere-egu24-73
Big Data, Mobility and Rhythms in Istanbul: A Data-Driven Analysis of Urban Temporal Dynamics
No full texthttps://doi.org/10.1007/s12061-025-09745-
Dynamic Casting: Using Deployable Fabric Formwork
No full textThe utilization of fabrics as formwork can facilitate a certain degree of flexibility in design, particularly when combined with deployable structures. Regarding this statement, the aim of this study is to explore the potential of a fabric formwork with deployable structure principles to prevent rigidity in the casting process. The deployable approach combined with fabric contributes to the study by allowing various configurations and reusability. A design-led methodology is adapted during this exploration based upon five phases: (1) crease pattern selection, (2) digital pattern creation, (3) deployable fabric formwork construction, (4) casting the concrete, and (5) comparing the physical model to computational model. Various models and mediums are used to examine the form behaviors along with the material relationship to highlight the collaboration between tools and craft to achieve a common goal. Therefore, the utilization of digital mediums is expected to improve the understanding of such a complex system as a dynamic mold fed by interdependent parameters. The results comparing the digital simulations and the several attempts to create the casting products displayed similar, if not identical, attributes. The differences between these models depend on the properties of the selected materials for both the deployable skeleton and the fabric.https://doi.org/10.53710/jcode.1512805https://dergipark.org.tr/tr/pub/jcode/issue/91045/151280
Leveraging Large Language Models to Improve Healthcare Accessibility in Underdeveloped Countries
No full texthttps://dx.doi.org/10.5281/zenodo.17114669https://dx.doi.org/10.5281/zenodo.1711466
Geleneksel İskoç ezgilerinin etkilediği klasik müzik eserlerinin Bela Bartok'un sınıflandırması kapsamında analizi
No full textThesis (M.Sc.) -- Istanbul Technical University, Graduate School, 2025Scottish folk music, like all folk traditions, has played a crucial role in shaping national identity, serving as both a cultural artefact and an artistic influence. In classical music, folk traditions have often been preserved through arrangements and adaptations, yet the interaction between folk and classical idioms is more complex than mere quotation. This research seeks to investigate how Scottish folk music has influenced classical composition, focusing on the implicit transmission of folk elements rather than direct melodic quotation. The primary framework for this study is Bela Bartok's tripartite classification of folk music's influence on classical composition, as explained in The Influence of Peasant Music on Modern Music. While Bartok's theory has been widely applied in the context of Eastern European music, it has not yet been systematically used to examine Scottish music before. By employing this model, this research has categorised Scottish- influenced classical compositions into three distinct types and, more importantly, established a refined third category that challenges conventional understandings of folk-inspired music. The key contribution of this research was to demonstrate that folk music could permeate classical compositions without direct quotation - a process often overlooked in previous studies. Rather than viewing folk influence as mere borrowing, this study explored how Scottish folk idioms, including rhythmic patterns, modal structures, and textural features, were subtly manifested within classical works and how these elements were embodied in classical compositions. The relationship between folk and classical music has been extensively studied in various contexts. Early research on Scottish folk music's integration into classical works focused on arrangements and adaptations of traditional melodies. Prominent examples include Beethoven's and Haydn's Scottish Song Arrangements and Mendelssohn's Scottish Symphony, all of which incorporate direct references to folk tunes. However, these works fall into Bartók's first two categories and do not fully account for more nuanced forms of folk music integration. Existing studies have examined composers influenced by Scottish folk music and identified explicit quotations of folk melodies, yet there has been little systematic analysis of works that embody folk characteristics without quoting specific tunes. This gap in the literature is where this study intervenes. Additionally, Bartók's theoretical framework has been applied primarily to Hungarian, Romanian, and Slovak folk music. This research contributes to the literature on folk- classical music interactions by extending Bartók's model and refining his third category as it applies to compositions that exhibit Scottish qualities without directly borrowing folk material. A significant number of examples were found during the analysis of selected pieces for the third category. By addressing this gap, the study broadens the application of Bartók's framework and offers a deeper understanding of how Scottish folk traditions subtly permeate classical compositions. This approach xvii provides a foundation for future research on implicit folk influences and encourages a reevaluation of how cultural identity is expressed in classical music. This study applies Béla Bartók's threefold classification of folk influence on classical music to Scottish repertoire. It focuses on Category 3 "Subconscious Folk Influence" highlighting works that do not directly quote folk melodies but embody Scottish characteristics through modality, rhythm, ornamentation, and instrumentation. Key examples include Hamish MacCunn's The Land of the Mountain and the Flood and James MacMillan's Tryst, which convey Scottish identity through modal harmonies, rhythmic gestures like the "Scottish snap," and drone-like pedal points reminiscent of bagpipes. The research also explores how features such as open intervals, repetitive phrasing, and folk dance forms subtly evoke oral folk traditions. By analyzing melodic, harmonic, and formal traits, this study proposes a new lens for identifying implicit folk elements in classical works, expanding our understanding of how folk idioms shape musical expression beyond direct quotation. This research establishes a foundational model for future studies on how folk traditions are assimilated into classical compositions beyond direct quotation. By demonstrating how folk music can influence classical language on a subconscious level, it bridges ethnomusicology and music analysis together. Ultimately, this study contributes to a broader understanding of Scottish musical identity and encourages a more nuanced approach to examining cross-genre musical interactions.M.Sc
Presence, Depth Distribution and Sources of Polycyclic Aromatic Hydrocarbons (Pahs) in the Deep-Sea Sediments of the Marmara Sea
No full texthttps://doi.org/10.2139/ssrn.522324