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Dijital İkiz Çatıyapısı Altında Yapısal Kirişlerin Fizik Bilgili Sinir Ağları ile Dinamik Modellenmesi
No full textDigital Twins (DT) are used in many fields, as well as to monitor the condition of structural parts according to the loads they are exposed to during operation. In the process of creating a digital copy of the physical product, Finite Element Method (FEM) is often involved. Although the complexity of the part geometry and mesh details are important in FEM applications, they affect the analysis time and thus the generation time of DT. Creating a digital copy with high-fidelity and low latency makes it possible to employ Artificial Intelligence (AI), which has found its place in many fields. In this study, we propose a Physics-Informed Neural Network (PINN) structure and DT framework that can perform high-fidelity modeling with fewer data by using the Partial Differential Equations (PDE) of the problem during the generation of the DT of structural beams. During the studies, synthetic data are generated with the help of analytical equations of the problem. Then, the generated data are fed into the PINN model to solve the forward problem and the inverse problem is solved to estimate the system parameters. A self-adaptive weight update method with a Neural Tangent Kernel (NTK) is applied to deal with the spectral bias phenomenon in high-frequency learning. The PINN estimates are compared with the Finite Element Analysis (FEA) outputs to prove the accuracy of the developed method. After the studies with synthetic data, a study is carried out with real data collected from the experimental setup, and the potential of PINNs to approximate the solution of nonlinear higher-order PDEs and parameter identification is demonstrated.Dijital İkiz (DT)'ler birçok alanda olduğu gibi yapısal parçaların çalışma anında maruz kaldıkları yüklere göre durum takibini yapmak için de kullanılmaktadır. Fiziksel ürünün dijital kopyasının oluşturulması aşamasında ise Sonlu Elemanlar Yöntemi (FEM) sıklıkla görev almaktadır. FEM uygulamalarında parça geometrisinin kompleksliği ve mesh detayları önemli olmakla beraber analiz sürelerini ve dolayısıyla DT oluşum süresini etkilemektedir. Doğruluğu yüksek ve gecikme süresi düşük bir dijital kopya oluşturulması aşamasında, birçok alanda kendisine yer bulan Yapay Zeka (AI)'dan faylanmak mümkündür. Bu çalışmada, yapısal kirişlerin DT'lerinin oluşturulması sırasında, içinde barındırdığı probleme ait Kısmi Diferansiyel Denklem (PDE)'lerden faydalanan, daha az veriyle yüksek doğruluklu modellemeler yapabilen Fizik Bilgili Sinir Ağları (PINN) yapısı ve bu yapının kullanıldığı bir DT çatıyasıpı önerilmektedir. Çalışmalar sırasında probleme ait analitik denklemler yardımıyla sentetik veriler üretilmiştir. Daha sonra üretilen veriler, PINN modeline beslenerek ileri problem çözülmüş ve ters problem çözümüyle de sistem parametreleri tahmin edilmiştir. Yüksek frekanslı öğrenmede spektral yanlılık (bias) fenomeni ile başa çıkmak için Neural Tangent Kernel (NTK) ile kendinden uyarlamalı ağırlık güncellemesi metodu uygulanmıştır. PINN tahminleri, geliştirilen yöntemin doğruluğunu kanıtlamak için Sonlu Elemanlar Analizi (FEA) çıktıları ile karşılaştırılmıştır. Sentetik verilerle yapılan çalışmalar sonrasında, deney düzeneğinden toplanan gerçek veriler ile de bir çalışma yapılmış ve PINN'lerin doğrusal olmayan yüksek dereceli PDE'leri
Drl-Based Joint Ap Deployment and Network-Centric Cluster Formation for Maximizing Long-Term Energy Efficiency in Cell-Free Massive Mimo
No full text57th Asilomar Conference on Signals, Systems and Computers, ACSSC 2023 -- 29 October 2023 through 1 November 2023 -- 198545In cell-free massive MIMO networks, scalability is one of the fundamental problems since a significant number of access points (APs) are widely distributed throughout the network area to cater to the needs of multiple user equipments (UEs). One approach to addressing this issue is through network-centric clustering, which involves dividing the network area into isolated clusters of APs, each connected to its cloud unit (CU). To address these challenges, this paper proposes a deep reinforcement learning (DRL) algorithm that jointly optimizes the network-centric cluster boundaries and decides AP deployment in each cluster to improve long-term energy efficiency. The DRL agent also aims to minimize the average UE drop rate by considering the delay requirements of each UE's requested service. The results show that at least 16% improvement in energy efficiency is obtained compared to the heuristically developed benchmarks. © 2023 IEEE
Search for Direct Production of Electroweakinos in Final States With One Lepton, Jets and Missing Transverse Momentum in Pp Collisions at √s=13 Tev With the Atlas Detector
No full textSearches for electroweak production of wino-like chargino pairs, (chi) over tilde (+)(1)(chi) over tilde (-), 1, and of wino-like chargino and next-to-lightest neutralino, (chi) over tilde (+/-)(1)(chi) over tilde (0)(2), are presented. The models explored assume that the charginos decay into a W boson and the lightest neutralino, (chi) over tilde chi(+/-)(1) -> W-+/- (chi) over tilde (0)(1) The next-to-lightest neutralinos are degenerate in mass with the chargino and decay to (chi) over tilde (0)(1) and either a Z or a Higgs boson, (chi) over tilde (0)(2) -> Z (chi) over tildeX(1)(0) or h (chi) over tilde (0)(1). The searches exploit the presence of a single isolated lepton and missing transverse momentum from the W boson decay products and the lightest neutralinos, and the presence of jets from hadronically decaying Z or W bosons or from the Higgs boson decaying into a pair of b-quarks. The searches use 139 fb(-1) of root s = 13TeV proton-proton collisions data collected by the ATLAS detector at the Large Hadron Collider between 2015 and 2018. No deviations from the Standard Model expectations are found, and 95% confidence level exclusion limits are set. Chargino masses ranging from 260 to 520 GeV are excluded for a massless (chi) over tilde (1)(0) in chargino pair production models. Degenerate chargino and next-to-lightest neutralino masses ranging from 260 to 420 GeV are excluded for a massless (chi) over tilde (1)(0) for (chi) over tilde (0)(2) -> Z (chi) over tilde (0)(1). For decays through an on-shell Higgs boson and for mass-splitting between (chi) over tilde (+/-)(1)/(chi) over tilde (0)(2) and (chi) over tilde (0)(1) as small as the Higgs boson mass, mass limits are improved by up to 40 GeV in the range of 200-260 GeV and 280-470 GeV compared to previous ATLAS constraints.ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW, Austria; FWF, Austria; ANAS, Azerbaijan; CNPq, Brazil; FAPESP, Brazil; NSERC, Canada; CFI, Canada; NSFC, China; NRC, Canada; CERN; ANID, Chile; CAS, China; MOST, China; Minciencias, Colombia; MEYS CR, Czech Republic; DNRF, Denmark; DNSRC, Denmark; IN2P3-CNRS, France; CEA-DRF/IRFU, France; SRNSFG, Georgia; BMBF, Germany; HGF, Germany; MPG, Germany; GSRI, Greece; RGC, China; Hong Kong SAR, China; ISF, Israel; Benoziyo Center, Israel; INFN, Italy; MEXT, Japan; JSPS, Japan; CNRST, Morocco; NWO, Netherlands; RCN, Norway; MEiN, Poland; FCT, Portugal; MNE/IFA, Romania; MESTD, Serbia; MSSR, Slovakia; ARRS, Slovenia; MIZS, Slovenia; DSI/NRF, South Africa; MICINN, Spain; SRC, Sweden; Wallenberg Foundation, Sweden; SERI, Switzerland; SNSF, Switzerland; Canton of Bern, Switzerland; Canton of Geneva, Switzerland; MOST, Taiwan; TENMAK, Turkiye; STFC, United Kingdom; DOE, United States of America; NSF, United States of America; BCKDF, Canada; CANARIE, Canada; Compute Canada, Canada; CRC, Canada; PRIMUS, Czech Republic [21/SCI/017]; UNCE, Czech Republic [SCI/013]; COST, European Union; ERC, European Union; ERDF, European Union; Horizon 2020, European Union; Marie Sklodowska-Curie Actions, European Union; Investissements d'Avenir Labex, France; Investissements d'Avenir Idex, France; ANR, France; DFG, Germany; AvH Foundation, Germany; Herakleitos programme - EU-ESF, Greece; Thales programme - EU-ESF, Greece; Aristeia programme - EU-ESF, Greece; Greek NSRF, Greece; BSF-NSF, Israel; MINERVA, Israel; Norwegian Financial Mechanism 2014-2021, Norway; NCN, Poland; NAWA, Poland; La Caixa Banking Foundation, Spain; CERCA Programme Generalitat de Catalunya, Spain; PROMETEO Programme Generalitat Valenciana, Spain; GenT Programme Generalitat Valenciana, Spain; Goran Gustafssons Stiftelse, Sweden; Royal Society, United Kingdom; Leverhulme Trust, United KingdomWe thank CERN for the very successful operation of the LHC, as well as the support staff from our institutions without whom ATLAS could not be operated efficiently. We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azerbaijan; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; ANID, Chile; CAS, MOST and NSFC, China; Minciencias, Colombia; MEYS CR, Czech Republic; DNRF and DNSRC, Denmark; IN2P3-CNRS and CEA-DRF/IRFU, France; SRNSFG, Georgia; BMBF, HGF and MPG, Germany; GSRI, Greece; RGC and Hong Kong SAR, China; ISF and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; NWO, Netherlands; RCN, Norway; MEiN, Poland; FCT, Portugal; MNE/IFA, Romania; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZS, Slovenia; DSI/NRF, South Africa; MICINN, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; TENMAK, Turkiye; STFC, United Kingdom; DOE and NSF, United States of America. In addition, individual groups and members have received support from BCKDF, CANARIE, Compute Canada and CRC, Canada; PRIMUS 21/SCI/017 and UNCE SCI/013, Czech Republic; COST, ERC, ERDF, Horizon 2020, ICSC-NextGenerationEU and Marie Skodowska-Curie Actions, European Union; Investissements d'Avenir Labex, Investissements d'Avenir Idex and ANR, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aristeia programmes co-financed by EU-ESF and the Greek NSRF, Greece; BSF-NSF and MINERVA, Israel; Norwegian Financial Mechanism 2014-2021, Norway; NCN and NAWA, Poland; La Caixa Banking Foundation, CERCA Programme Generalitat de Catalunya and PROMETEO and GenT Programmes Generalitat Valenciana, Spain; Goran Gustafssons Stiftelse, Sweden; The Royal Society and Leverhulme Trust, United Kingdom. The crucial computing support from all WLCG partners is acknowledged gratefully, in particular from CERN, the ATLAS Tier-1 facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Sweden), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy), NL-T1 (Netherlands), PIC (Spain), ASGC (Taiwan), RAL (U.K.) and BNL (U.S.A.), the Tier-2 facilities worldwide and large non-WLCG resource providers. Major contributors of computing resources are listed in ref. [124]
Coverage Hole Optimization With a Mobile Sensor in Wireless Sensor Networks for Smart Grid
No full textThe Smart Grid (SG) enables electricity and energy exchange between two ends of the grid. Wireless Sensor Networks (WSNs) are considered as an enabling communication technology for effective SG management. How well the target region is covered by a WSN indicates the service quality of the relevant implementation. Since effective monitoring is key to exploiting the benefits of the SG, maintaining the desired coverage level is critical in WSN for SG applications. However, some uncovered regions (coverage holes) might emerge due to several reasons such as improper localization or sensor malfunctioning. In this paper, we propose using a mobile sensor to cover such blind regions in a timely and hence energy-efficient way. First, we present a novel 0-1 mixed integer programming model without restrictive assumptions about the mobility pattern to find the shortest trajectory for the mobile sensor. Then we show that the problem is NP-hard with a polynomial reduction to the Traveling Salesman Problem. Consequently, we present an optimization-based heuristic, two heuristic-based algorithms, and a hybrid algorithm. We show that our heuristics are efficient as they find high quality solutions in a few seconds. We also observe that assumptions about the starting point of the tour and the potential set of stops significantly affect the final tour's length.This work was supported by the TUBITAK, Turkey Grant with project 219M436.TUBITAK, Turkey Grant [219M436
Finansal Basari ile Mali Oranlar İliskisinin İncelenmesi ve Fuzzy Logic Metodu ile Finansal Sürdürebilir Basari Ölçümü
No full textFinansal başarı firmaların ve paydaşlarının önem verdiği konulardan bir tanesi konumundadır. Bir firmanın finansal açıdan başarılı olması yöneticilerini, çalışanlarını, ortaklarını ve kredi kurumlarını kısacası tüm paydaşlarını memnun eden bir durumdur. Bu çalışmada Borsa İstanbul'da işlem gören şirketlerin finansal başarılı olma durumlarının mali oranlarla olan ilişkisini analiz etmek için lojistik regresyon modeli kullanılmıştır. Oluşturulan modelde 16 mali oranın 11 tanesinin yüksek olması finansal başarı ihtimalini artırırken 5 tanesi finansal başarı ihtimalini düşürdüğü sonucu tespit edilmiştir. Şirketleri finansal sürdürülebilirlik seviyelerine göre sınıflandırabilmek için bulanık mantık yöntemi kullanılmıştır. Oluşturulan metot ile şirketlerin göreceli finansal sürdürülebilirlik düzeylerini ölçen bir gösterge oluşturulmuştur. Bu göstergede şirketlerin hangi yönlerinin daha güçlü olduğu tespit edilmiştir. 110 şirket için finansal sürdürülebilirlik düzeylerine göre sıralama oluşturulmuştur.Financial success is one of the issues that companies and their stakeholders attach importance to. The financial success of a company is a situation that pleases its managers, employees, partners and credit institutions, in short, all its stakeholders. In this study, a logistic regression model was used to analyze the relationship between financial success and financial ratios of companies traded in Borsa Istanbul. In the model created, it has been determined that 11 of the 16 financial ratios are high, while increasing the probability of financial success, while 5 of them decrease the probability of financial success. Fuzzy logic method was used to classify companies according to their financial sustainability levels. With the created method, an indicator was created that measures the relative financial sustainability levels of companies. In this indicator, it was determined which aspects of the companies were stronger. A ranking was created for 110 companies according to their financial sustainability levels
Dna Origami Nanoyapıların Yapısal Kararlılığının ve Elektronik Özelliklerinin Moleküler Dinamik ve Yoğunluk Fonksiyonel Teorisi Simülasyonları ile İncelenmesi
No full textDeoxyribonucleic acid (DNA) is the fundamental molecule that is responsible from the genetic information in living organisms. It also has a great potential in nanotechnology applications due to its unique interactions of complementary base pairs and the ability to be produced easily in a desired sequence. Combination of a long, single DNA strand with shorter DNA strands can result in desired two- or three – dimensional nanostructures which is called "DNA Origami". DNA origami nanostructures have a high potential for various applied research such as drug delivery, biosensing, inorganic material synthesis, as well as molecular electronics applications, which have gained momentum in recent years due to their ease of production. DNA origami nanostructures designed for these applications should maintain their structural stability and should be able to be designed with desired properties for electronic applications. Although it is known that the stability of the DNA origami structures depends on geometry, helix number, and environmental conditions, the nature of these effects has so far been poorly understood. In addition, understanding the effects of structural changes on the electronic properties of DNA origami is crucial for the development of new electronic devices. In this thesis, three-dimensional structures of different DNA origami nanostructures were modeled by using molecular dynamics methods with AMBER and NAMD programs. The effects of three different parameters on the conformation of DNA origami nanostructures were investigated via modeling methods: 1) gold (111) surface, 2) frequency of junction points of DNA helixes, and 3) salt concentration difference. Smaller double-stranded DNA molecules representing DNA origami structures were created and the effects of structural deformations due to the gold (111) surface on electronic properties were inspected using the GAUSSIAN program. In addition, the structural stability of the DNA origami nanostructure within the 1,2-Dioleoyl-sn-glycero-3-phosphocholine (DOPC) lipid bilayer for bioelectronic applications was examined. Then, energy band diagrams and molecular orbital positions were studied with Extended Hückel and density functional theory calculations. The transmission of electrical conductivity between the helices in DNA origami structures was explored. It is expected that these studies will contribute to the development of new nanotechnological devices and applications in the future by paving the way for the understanding of the structural stability of DNA origami and the long-term use of DNA origami structures.Deoksiribonükleik asit (DNA) canlılarda genetik bilgiyi oluşturan temel moleküldür. Bunun yanı sıra, tamamlayıcı nükleotid çiftlerinin kendilerine has etkileşimleri ve nükleotidlerin istenilen diziler halinde kolayca üretilebilmesi nedeniyle nanoteknoloji uygulamalarında önemli bir potansiyele sahiptir. Uzun, tek iplikli DNA molekülünün, daha kısa iplikli DNA'lar ile birleştirilmesi sonucunda, "DNA Origami" olarak adlandırılan, istenilen şekillerde iki veya üç boyutlu nanoyapılar elde edilebilmektedir. DNA origami nanoyapılar, ilaç taşınımı, biyoalgılayıcı, inorganik malzeme sentezi gibi çeşitli uygulamalı araştırmaların yanı sıra üretim kolaylığı nedeniyle, son yıllarda hız kazanan moleküler elektronik uygulamaları için de yüksek potansiyele sahiptir. Bahsedilen bu uygulamalar için DNA origami kullanılarak cihazların üretilebilmesi ve uzun süreli dayanıklılığı, tasarlanan nanoyapılarının yapısal kararlılıklarını korumasına ve ayrıca elektronik özelliklerinin uygulamaya yönelik olarak tasarlanabilmesine bağlıdır. DNA origami yapısının kararlılığının geometri, sarmal sayısı ve çevresel koşullara bağlı olduğu bilinse de bu etkilerin doğası şimdiye kadar çok az anlaşılmıştır. Ayrıca yapısal değişikliklerin DNA origamilerin elektronik özellikleri üzerindeki etkilerini anlamak yeni elektronik cihazların geliştirilmesi için önemlidir. Bu tez kapsamında AMBER ve NAMD programları ile moleküler dinamik simülasyonları kullanılarak farklı DNA origami nanoyapılarının üç boyutlu yapıları modellendi. DNA origami nanoyapılarının konformasyonları üzerinde üç farklı parametrenin etkileri modelleme yöntemleri ile araştırıldı: 1) altın (111) yüzeyi, 2) DNA sarmallarının bağlantı noktalarının sıklığı ve 3) tuz konsantrasyon farkı. DNA origami yapılarını temsil eden daha küçük çift sarmal DNA molekülleri oluşturuldu ve altın (111) yüzeyiyle etkileşimler nedeniyle meydana gelen yapısal deformasyonların elektronik özelliklere olan etkileri GAUSSIAN programı kullanılarak incelendi. Ayrıca, biyoelektronik uygulamalar için DNA origami nanoyapısının 1,2-Dioleoil-sn-glisero-3-fosfokolin (DOPC) lipit çift tabakası içerisindeki yapısal kararlılığı araştırıldı. Daha sonra genişletilmiş Hückel metodu ve yoğunluk fonksiyonel teorisi hesaplamaları ile enerji bant diyagramları ve moleküler orbital pozisyonları araştırıldı. DNA origami yapılarında elektriksel iletkenliğin sarmallar arasındaki iletimi incelendi. Bu çalışmaların DNA origamilerin yapısal kararlılıklarının anlaşılmasına ve DNA origami yapılarının uzun vadeli kullanımının önünü açarak ileride nanoteknolojik yeni cihazların ve uygulamaların geliştirilmesine katkı sağlaması beklenmektedir
The History and Problems of Experimental Digital Pinball and Developing a Pinball Video Game Concept Based on Music
No full textPinball games may have lost their popularity over time; however, developers revived their features inside other video games or completely renovated them. While arcade pinball machines offer limited gameplay, digital pinball can be much more flexible. Nevertheless, according to the author’s preliminary investigation, academic research is lacking in pinball gaming. This artistic paper attempts to close this gap by shedding light on experimental digital pinball games. Moreover, the author focuses on music visualization features of digital pinball games, and he developed an experimental pinball video game concept based on synaesthesia by answering a simple question, “How does a classical music-based pinball video game would look like?”
An Architectural Framework for the Allocation Resources in Emergency Management Systems
No full textEmergency management systems are considered critical systems (EU Commission, 2006 [1]). It is, therefore, necessary that emergency management systems operate with high effectiveness and efficiency. This requires accurate detection of emergency conditions and optimal allocation of the available resources. In the case of large-scale disasters and insufficient resources, however, manual prioritizing and compromising resources can be extremely difficult. This chapter proposes a novel architectural framework that automatically converts emergency reports to a set of rescue tasks to be scheduled. If tasks cannot be scheduled as desired due to conflicts in allocating resources, control algorithms are applied. This architecture allows the introduction of new disaster types and control strategies if needed. The framework is designed and implemented in a simulated environment and its utility is tested with various emergency scenarios. © 2024 Elsevier Inc. All rights reserved