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Permanent URI for this collectionhttps://hdl.handle.net/20.500.14288/3
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Publication Metadata only The digital twin synchronization problem: framework, formulations, and analysis(Taylor & Francis Inc, 2023) Matta, Andrea; Department of Business Administration; Tan, Barış; Department of Business Administration; College of Administrative Sciences and EconomicsAs the adoption of digital twins increases steadily, it is necessary to determine how to operate them most effectively and efficiently. In this article, the digital twin synchronization problem is introduced and defined formally. Frequent synchronizations would increase cost and data traffic congestion, whereas infrequent synchronizations would increase the bias of the predictions and yield wrong decisions. This work defines the synchronization problem variants in different contexts. To discuss the problem and its solution, the problem of determining when to synchronize an unreliable production system with its digital twin to minimize the average synchronization and bias costs is formulated and analyzed analytically. The state-independent, state-dependent, and full-information solutions have been determined by using a stochastic model of the system. Solving the synchronization problem using simulation is discussed, and an approximate policy is proposed. Our results show that the performance of the state-dependent policy is close to the optimal solution that can be obtained with full information and significantly better than the performance of the state-independent policy. Furthermore, the approximate periodic state-dependent policy yields near-optimal results. To operate digital twins more effectively, the digital twin synchronization problem must be considered and solved to determine the optimal synchronization policy.Publication Metadata only Diagnosis and management in Rubinstein-Taybi syndrome: first international consensus statement(BMJ Publishing Group, 2024) Lacombe, Didier; Bloch-Zupan, Agnès; Bredrup, Cecilie; Cooper, Edward B; Houge, Sofia Douzgou; García-Miñaúr, Sixto; Larizza, Lidia; Lopez Gonzalez, Vanesa; Menke, Leonie A; Milani, Donatella; Saettini, Francesco; Stevens, Cathy A; Tooke, Lloyd; Van der Zee, Jill A; Genderen, Maria M Van; Van-Gils, Julien; Waite, Jane; Adrien, Jean-Louis; Bartsch, Oliver; Bitoun, Pierre; Bouts, Antonia H M; Cueto-González, Anna M; Dominguez-Garrido, Elena; Duijkers, Floor A; Fergelot, Patricia; Halstead, Elisabeth; Huisman, Sylvia A; Meossi, Camilla; Mullins, Jo; Nikkel, Sarah M; Oliver, Chris; Prada, Elisabetta; Rei, Alessandra; Riddle, Ilka; Rodriguez-Fonseca, Cristina; Pena, Rebecca Rodríguez; Russell, Janet; Saba, Alicia; Santos-Simarro, Fernando; Simpson, Brittany N; Smith, David F; Stevens, Markus F; Szakszon, Katalin; Taupiac, Emmanuelle; Totaro, Nadia; Palafoll, Irene Valenzuena; Van Der Kaay, Daniëlle C M; Van Wijk, Michiel P; Vyshka, Klea; Wiley, Susan; Hennekam, Raoul C; Kayserili, Hülya; School of MedicineRubinstein-Taybi syndrome (RTS) is an archetypical genetic syndrome that is characterised by intellectual disability, well-defined facial features, distal limb anomalies and atypical growth, among numerous other signs and symptoms. It is caused by variants in either of two genes (CREBBP, EP300) which encode for the proteins CBP and p300, which both have a function in transcription regulation and histone acetylation. As a group of international experts and national support groups dedicated to the syndrome, we realised that marked heterogeneity currently exists in clinical and molecular diagnostic approaches and care practices in various parts of the world. Here, we outline a series of recommendations that document the consensus of a group of international experts on clinical diagnostic criteria for types of RTS (RTS1: CREBBP;RTS2: EP300), molecular investigations, long-term management of various particular physical and behavioural issues and care planning. The recommendations as presented here will need to be evaluated for improvements to allow for continued optimisation of diagnostics and care. © 2024 BMJ Publishing Group. All rights reserved.Publication Metadata only Number of least area planes in gromov hyperbolic 3-spaces(American Mathematical Society (AMS), 2010) Department of Mathematics; Coşkunüzer, Barış; Faculty Member; Department of Mathematics; College of Sciences; N/AWe show that for a generic simple closed curve Gamma in the asymptotic boundary of a Gromov hyperbolic 3-space with cocompact metric X, there exists a unique least area plane Sigma in X such that partial derivative(infinity)Sigma = Gamma. This result has interesting topological applications for constructions of canonical 2-dimensional objects in Gromov hyperbolic 3-manifolds.Publication Metadata only Working memory capacity and controlled serial memory search(Elsevier, 2016) N/A; Department of Psychology; Mızrak, Eda; Öztekin, İlke; PhD Student; Faculty Member; Department of Psychology; Graduate School of Social Sciences and Humanities; College of Social Sciences and Humanities; N/A; N/AThe speed-accuracy trade-off (SAT) procedure was used to investigate the relationship between working memory capacity (WMC) and the dynamics of temporal order memory retrieval. High- and low-span participants (HSs, LSs) studied sequentially presented five-item lists, followed by two probes from the study list. Participants indicated the more recent probe. Overall, accuracy was higher for HSs compared to LSs. Crucially, in contrast to previous investigations that observed no impact of WMC on speed of access to item information in memory (e.g., Oztekin & McElree, 2010), recovery of temporal order memory was slower for LSs. While accessing an item's representation in memory can be direct, recovery of relational information such as temporal order information requires a more controlled serial memory search. Collectively, these data indicate that WMC effects are particularly prominent during high demands of cognitive control, such as serial search operations necessary to access temporal order information from memory. (C) 2016 Elsevier B.V. All rights reserved.Publication Metadata only Risk-sensitive control of branching processes(Taylor and Francis inc, 2021) Department of Industrial Engineering; Canbolat, Pelin Gülşah; Faculty Member; Department of Industrial Engineering; College of Engineering; 108242This article solves the risk-sensitive control problem for branching processes where the one-period progeny of an individual can take values from a finite set. the decision maker is assumed to maximize the expected risk-averse exponential utility (or to minimize the expected risk-averse exponential disutility) of the rewards earned in an infinite horizon. individuals are assumed to produce progeny independently, and with the same probability mass function if they take the same action. This article characterizes the expected disutility of stationary policies, identifies necessary and sufficient conditions for the existence of a stationary optimal policy that assigns the same action to all individuals in all periods, and discusses computational methods to obtain such a policy. are available for this article. See the publisher's online edition of IIE Transactions, datasets, Additional tables, detailed proofs, etc.Publication Metadata only Automatic detection of road types from the third military mapping survey of Austria-Hungary historical map series with deep convolutional neural networks(IEEE-inst Electrical Electronics Engineers inc, 2021) N/A; N/A; Department of History; Can, Yekta Said; Gerrits, Petrus Johannes; Kabadayı, Mustafa Erdem; Resercher; Master Student; Faculty Member; Department of History; College of Social Sciences and Humanities; Graduate School of Social Sciences and Humanities; College of Social Sciences and Humanities; N/A; N/A; 33267With the increased amount of digitized historical documents, information extraction from them gains pace. Historical maps contain valuable information about historical, geographical and economic aspects of an era. Retrieving information from historical maps is more challenging than processing modern maps due to lower image quality, degradation of documents and the massive amount of non-annotated digital map archives. Convolutional Neural Networks (CNN) solved many image processing challenges with great success, but they require a vast amount of annotated data. for historical maps, this means an unprecedented scale of manual data entry and annotation. in this study, we first manually annotated the Third Military Mapping Survey of austria-Hungary historical map series conducted between 1884 and 1918 and made them publicly accessible. We recognized different road types and their pixel-wise positions automatically by using a CNN architecture and achieved promising results.Publication Metadata only Evidence for amino acid snorkeling from a high-resolution, in vivo analysis of FIS1 tail-anchor insertion at the mitochondrial outer membrane(Genetics Society America, 2017) N/A; N/A; N/A; Department of Molecular Biology and Genetics; Keskin, Abdurrahman; Akdoğan, Emel; Dunn, Cory David; Master Student; Master Student; Other; Department of Molecular Biology and Genetics; Graduate School of Sciences and Engineering; Graduate School of Sciences and Engineering; College of Sciences; N/A; N/A; N/AProteins localized to mitochondria by a carboxyl-terminal tail anchor (TA) play roles in apoptosis, mitochondrial dynamics, and mitochondrial protein import. To reveal characteristics of TAs that may be important for mitochondrial targeting, we focused our attention upon the TA of the Saccharomyces cerevisiae Fis1 protein. Specifically, we generated a library of Fis1p TA variants fused to the Gal4 transcription factor, then, using next-generation sequencing, revealed which Fis1p TA mutations inhibited membrane insertion and allowed Gal4p activity in the nucleus. Prompted by our global analysis, we subsequently analyzed the ability of individual Fis1p TA mutants to localize to mitochondria. Our findings suggest that the membrane-associated domain of the Fis1p TA may be bipartite in nature, and we encountered evidence that the positively charged patch at the carboxyl terminus of Fis1p is required for both membrane insertion and organelle specificity. Furthermore, lengthening or shortening of the Fis1p TA by up to three amino acids did not inhibit mitochondrial targeting, arguing against a model in which TA length directs insertion of TAs to distinct organelles. Most importantly, positively charged residues were more acceptable at several positions within the membrane-associated domain of the Fis1p TA than negatively charged residues. These findings, emerging from the first high-resolution analysis of an organelle targeting sequence by deep mutational scanning, provide strong, in vivo evidence that lysine and arginine can "snorkel," or become stably incorporated within a lipid bilayer by placing terminal charges of their side chains at the membrane interface.Publication Metadata only Expertise at the intersection of technicality and ambiguity: international governance of gender and development(Routledge Journals, Taylor & Francis Ltd, 2022) Department of International Relations; Olcay, Özlem Altan; Faculty Member; Department of International Relations; College of Administrative Sciences and Economics; 104197This paper studies processes of expert authorisation in international institutions of governance. Based on interviews with gender experts, it focuses on discourses of women's empowerment to reveal two strategies that experts deploy: the production of technical frames and indicators for capturing empowerment while also generating ambiguity about its meaning. I argue that technicalisation and mystification are expert strategies used to navigate organisational priorities and diverse political convictions. I propose that we need to analyse expert knowledge production not just as the cause of depoliticisation of policy problems, but also as part of other institutional processes within which expertise has to be authorised. The ongoing nature of such contestations and negotiations bears on who is acknowledged as an expert and the extent of their authority. The problem is not always expert authority but rather its dependence on political processes devised by actors who retain power by remaining behind the scenes.Publication Metadata only Adaptation strategies for MGS scalable video streaming(Elsevier, 2012) N/A; Department of Electrical and Electronics Engineering; Görkemli, Burak; Tekalp, Ahmet Murat; N/A; Faculty Member; Department of Electrical and Electronics Engineering; College of Engineering; College of Engineering; N/A; 26207An adaptive streaming framework consists of a video codec that can produce video encoded at a variety of rates, a transport protocol that supports an effective rate/congestion control mechanism, and an adaptation strategy in order to match the video source rate to the available network throughput. The main parameters of the adaptation strategy are encoder configuration, video extraction method, determination of video extraction rate, send rate control, retransmission of lost packets, decoder buffer status, and packetization method. This paper proposes optimal adaptation strategies, in terms of received video quality and used network resources, at the codec and network levels using a medium grain scalable (MGS) video codec and two transport protocols with built-in congestion control, TCP and DCCP. Key recommendations are presented to obtain the best results in adaptive video streaming using TCP or DCCP based on extensive experimental results over the Internet. (c) 2012 Elsevier B.V. All rights reserved.Publication Metadata only Demixing pressures of hydroxy-terminated poly(dimethylsiloxane)-carbon dioxide binary mixtures at 313.2 K, 323.2 K and 333.2 K(Elsevier Science Bv, 2014) N/A; Department of Chemical and Biological Engineering; Şanlı, Deniz; Erkey, Can; Researcher; Faculty Member; Department of Chemical and Biological Engineering; Koç University Tüpraş Energy Center (KUTEM) / Koç Üniversitesi Tüpraş Enerji Merkezi (KÜTEM); Graduate School of Sciences and Engineering; College of Engineering; N/A; 29633The phase behavior of PDMS(OH)-CO2 binary mixtures was investigated. Two different molecular weight PDMS(OH) were utilized and the demixing pressures were determined at three temperatures for a wide composition range. Both of these polymers were found to form miscible mixtures with CO2 at all compositions at pressures lower than 31 MPa in the temperature range 313.2-333.2 K. Depending on the composition of the binary mixtures, two types of phase separation was observed during depressurization; the bubble point and the cloud point. In addition, at specific weight fractions a color change was also observed which was attributed to the mixture critical point. The demixing pressures were observed to increase with temperature and decrease with increasing polymer weight fraction. In addition, higher demixing pressures were obtained for the higher molecular weight polymer mixtures. The bubble point data were modeled by using Sanchez-Lacombe equation of state (SLEoS) and the binary interaction parameters were regressed at the studied temperatures. It was observed that the binary interaction parameters decreased with increasing temperature.