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Measurements of Jet Observables Sensitive To B-Quark Fragmentation in (tt)over-Bar Events at the Lhc With the Atlas Detector
No full textSeveral observables sensitive to the fragmentation of b quarks into b hadrons are measured using 36 fb(-1) of root s = 13 TeV proton-proton collision data collected with the ATLAS detector at the LHC. Jets containing b hadrons are obtained from a sample of dileptonic (tt) over bar events, and the associated set of charged-particle tracks is separated into those from the primary pp interaction vertex and those from the displaced b-decay secondary vertex. This division is used to construct observables that characterize the longitudinal and transverse momentum distributions of the b hadron within the jet. The measurements have been corrected for detector effects and provide a test of heavy-quark-fragmentation modeling at the LHC in a system where the top-quark decay products are color connected to the proton beam remnants. The unfolded distributions are compared with the predictions of several modern Monte Carlo parton-shower generators and generator tunes, and a wide range of agreement with the data is observed, with p values varying from 5 x 10(-4) to 0.98. These measurements complement similar measurements from e(+)e(-) collider experiments in which the b quarks originate from a color singlet Z/gamma*.ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW, Austria; FWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq, Brazil; FAPESP, Brazil; NSERC, Canada; NRC, Canada; CFI, Canada; CERN; ANID, Chile; CAS, China; NSFC, 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; JINR; MES of Russia, Russian Federation; NRC KI, Russian Federation; 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; TAEK, Turkey; STFC, United Kingdom; DOE, United States of America; NSF, United States of America; BCKDF, Canada; CANARIE, Canada; Compute Canada, Canada; CRC, Canada; 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 program - EU-ESF, Greece; Thales program - EU-ESF, Greece; Aristeia program - EU-ESF, Greece; Greek NSRF, Greece; BSF-NSF, Israel; GIF, Israel; Norwegian Financial Mechanism 2014-2021, Norway; NCN, Poland; NAWA, Poland; La Caixa Banking Foundation, Spain; CERCA Programme Generalitat de Catalunya, Spain; ROMETEO 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; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; ANID, Chile; CAS, MOSTand 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; JINR; MES of Russia and NRC KI, Russian Federation; 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; TAEK, Turkey; 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; COST, ERC, ERDF, Horizon 2020 and Marie Sklodowska-Curie Actions, European Union; Investissements d'Avenir Labex, Investissements d'Avenir Idex and ANR, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aristeia programs cofinanced by EU-ESF and the Greek NSRF, Greece; BSF-NSF and GIF, 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 (UK) and BNL (USA), the Tier-2 facilities worldwide and large non-WLCG resource providers. Major contributors of computing resources are listed in Ref. 32]
Evaluation of Retinal Layer Thicknesses in Patients With Keratoconus Using Retinal Layer Segmentation Analysis
No full textArticle; Early AccessObjective To conduct an evaluation of the effects of irregular astigmatism on the retinal nerve fiber layer (RNFL) and the retinal layers observed using spectral-domain optical coherence tomography (SD-OCT) in patients who had keratoconus (KC). Materials and Methods A total of 255 eyes from 255 individuals, comprising 72 eyes of KC patients, 70 eyes of patients with astigmia, and 113 eyes of healthy controls were included in the analysis. RNFL scan maps (comprising global, temporal, superotemporal, inferotemporal, nasal, inferonasal, and superonasal maps) and macular thickness (MT) maps of a standard from the Early Treatment Diabetic Retinopathy Study (ETDRS) grid were assessed. The measurements were segmented automatically using Spectralis software, and included the RNFL, inner and outer plexiform layers (IPL, OPL), inner and outer nuclear layers (INL, ONL), ganglion cell layer, retinal pigment epithelium (RPE) in the central 6-mm ETDRS subfield. Results The RNFL thickness in the KC group was lower when compared with the other two groups; however, statistically significant differences were noted in the global, temporal, superotemporal, and inferotemporal sectors (p 0.05 for all). All of the central MT parameters showed significant variation among the groups, while a statistically significant decrease was noted in the KC group, except in the inferior outer sector (p = 0.741). In the segmentation analysis, the KC group had the significantly lowest IPL, ONL, RPE, and outer retinal layer (ORL) thickness among the groups (p 0.05 for each). The astigmatic group was similar to the control group with regard to these parameters (p > 0.05 for each). Conclusion The eyes in the KC group appeared to have a thinner RNFL and MT when compared to those in the astigmatic and control groups. The ORLs, especially the ONL and RPE, were the most affected component of the macula in the KC group
Mors: an Approximate Fault Modelling Framework for Reduced-Voltage Srams
No full textOn-chip memory (usually based on Static RAMs-SRAMs) are crucial components for various computing devices including heterogeneous devices, e.g, GPUs, FPGAs, ASICs to achieve high performance. Modern workloads such as Deep Neural Networks (DNNs) running on these heterogeneous fabrics are highly dependent on the on-chip memory architecture for efficient acceleration. Hence, improving the energy-efficiency of such memories directly leads to an efficient system. One of the common methods to save energy is undervolting i.e., supply voltage underscaling below the nominal level. Such systems can be safely undervolted without incurring faults down to a certain voltage limit. This safe range is also called voltage guardband. However, reducing voltage below the guardband level without decreasing frequency causes timing-based faults. In this paper, we propose MoRS, a framework that generates the first approximate undervolting fault model using real faults extracted from experimental undervolting studies on SRAMs to build the model. We inject the faults generated by MoRS into the on-chip memory of the DNN accelerator to evaluate the resilience of the system under the test. MoRS has the advantage of simplicity without any need for high-time overhead experiments while being accurate enough in comparison to a fully randomly-generated fault injection approach. We evaluate our experiment in popular DNN workloads by mapping weights to SRAMs and measure the accuracy difference between the output of the MoRS and the real data. Our results show that the maximum difference between real fault data and the output fault model of MoRS is 6.21%, whereas the maximum difference between real data and random fault injection model is 23.2%. In terms of average proximity to the real data, the output of MoRS outperforms the random fault injection approach by 3.21x. IEE
Waveguide-To Vertical Bend Coupler Design for 3d Photonic Integrated Circuits
No full textConference on Integrated Photonics Platforms II -- APR 03-MAY 20, 2022 -- ELECTR NETWORKA waveguide-to-substrate, vertical bend coupler that is based on genetic algorithm is introduced to couple and direct the optical flow in 3D photonic integrated circuits. The vertical coupler device enables high-efficiency broadband optical transmission between different dielectric layers over comparable distances to the coupler's length. The vertical coupler attains an adept transition between a silicon waveguide and a planar Si layer separated by a SiO2 spacer. The simulation results of the designed vertical coupler device show a coupling ratio of -3.4 dB at 1550 nm wavelength and at 1 mu m vertical transition depth, thanks to the effective manipulation of light. The coupler possesses a miniscule area of 2 mu m x 2 mu m compared to its conventional counterparts. Our proposed waveguide-to-substrate coupler represents an unprecedented, elevated solution with high- efficiency and broadband operation for the vertical transition in 3D photonic integrated circuits. It can take an important part in overcoming the obstacles on the way of 3D photonic integrated circuits for virtual reality and quantum computing applications.H.A.G. acknowledges the partial support from the Scientific and Technical Research Council (TUBITAK) 2210A Grant. This project is supported by TUBITAK under grant 119E501.SPIE,IdEx Univ Strasbourg,CNRS,ICube,Univ StrasbourgScientific and Technical Research Council (TUBITAK) [2210A]; TUBITAK [119E501
Ethereum Akıllı Kontratları için Güvenlik Denetim Metodolojisi
No full textSmart contracts are small programs that work under blockchain technology and are written to achieve certain purposes. The principle of immutability, which is one of the most fundamanetal features of blockchain technology, also applies to smart contracts. This means that a contract deployed to the chain is resistant to modification and manipulation. However, this means that the logic errors and vulnerabilities in the contracts cannot be fixed after they are uploaded to the chain. For attackers, this is a great convenience. To prevent this, security checks are applied to smart contract projects before they are uploaded to the block. However, sometimes these controls are insufficient and projects become the target of attackers. In this study, it is aimed to examine the events that have a significant impact on the Ethereum ecosystem, to detect if there is a deficiency in the audits of the projects, and to suggest a comprehensive audit methodology by examining the frequently encountered vulnerabilities in the ecosystem, and thus to prevent the mentioned events from happening to the contracts audited with this methodology. When the audit reports of the projects in the Ethereum ecosystem that were previously audited and the target of important attacks are examined, it has been seen that it is possible to prevent the vast majority of them. It was observed that the reason for this was the points that were overlooked while examining the business logic in question and the processes that only rely on automated tools. In addition, it is seen that 60% of the active vulnerabilities in the vulnerabilities examined in the study are caused by user negligence. Such vulnerabilities are easier to detect than logical ones, both for vehicles and humans. To sum up, it is reasonable to say that the methodology proposed in this study aims to combine manual analysis with automated tools. The methodology, which accepts manual analysis methods as its basis, explains the points to be considered during both static and dynamic manual analysis and how these points should be examined. It uses automated tools where manual analysis methods are lacking, such as endpoint testing, overlooked points, and verification of false positives or negatives. In this way, it is ensured that the two approaches are used in a way that makes up for each other's deficiencies and a comprehensive audit is provided.Akıllı kontratlar blokzincir teknolojisi altında çalışan, belli amaçları gerçekleştirmek için yazılmış küçük programlardır. Blokzincir teknolojisinin en temel özelliklerinden olan değişmezlik ilkesi akıllı kontratlar için de geçerlidir. Bu da zincire yüklenmiş olan bir kontratın değiştirme ve manipülasyonlara karşı dirençli olduğu anlamına gelir. Bu kontratlarda bulunan mantık hatalarının ve zafiyetli kısımların zincire yüklendikten sonra değiştirilemeyeceği anlamına da gelmektedir. Saldırganlar için bu durum büyük bir kolaylıktır. Bunu önlemek için akıllı kontrat projeleri bloğa yüklenmeden önce üstlerinde güvenlik denetimleri uygulanmaktadır. Ancak kimi zaman bu denetimler de yetersiz kalır ve projeler saldırganların hedefi olur. Bu çalışmada Ethereum ekosisteminde meydana gelmiş olaylardan önemli etkiye sahip olanları incelenerek projelerin denetimlerinde bir eksik varsa bunu tespit etmek ve buna ek olarak ekosisteminde sıkça rastlanan zafiyetleri inceleyerek kapsamlı bir denetim metodolojisi önermek ve bu sayede bahsi geçen olayların bu metodoloji ile denetlenen kontratların başına gelmesinin önlenmesi amaçlanmıştır. Ethereum ekosistemindeki daha önceden denetlenmiş ve önemli saldırıların hedefi olan projelerin denetleme raporları incelendiğinde, büyük çoğunluğunun önüne geçebilmenin mümkün olduğu görülmüştür. Bunun nedeninin ise söz konusu projelerin işletme mantıkları incelenirken gözden kaçan noktalar ve sadece otomatik araçlara güvenen süreçler olduğu gözlemlenmiştir. Buna ek olarak çalışmada incelenen zafiyetlerde etkin zafiyetlerin %60'ının kullanıcı ihmallerinden kaynaklandığı görülmektedir. Bu tarz zafiyetlerin tespiti mantıksal eksikliklere göre daha kolaydır, hem araçlar hem insanlar için. Tüm anlatılanlar göz önüne alındığında bu çalışmada önerilen metodolojinin kabaca manuel analiz ile otomatik araçları bir arada kullanmayı hedeflediğini söylemek makuldür. Manuel analiz yöntemlerini esas olarak kabul eden metodoloji hem statik hem dinamik manuel analiz sırasında dikkat edilmesi gereken noktaları ve bu noktaların nasıl incelenmesi gerektiğini anlatır. Otomatik araçları ise manuel analiz yöntemlerinin eksik kaldığı, uç nokta testleri, gözden kaçan noktalar, hatalı pozitif veya negatiflerin doğrulanması gibi noktalarda kullanır. Bu sayede iki yaklaşımın birbirlerini eksiklerini kapatacak şekilde kullanılması sağlanmış olur ve kapsamlı bir denetim sağlanır
Hukukun Üstünlüğünün Bir Unsuru Olarak Merkez Bankasi Bağimsizliği
No full textMerkez bankası bağımsızlığı son dönemde yaygın olarak hem Türkiye’de hem de dünyada bir tartışma konusu haline gelmiştir. Bu tartışmalarda merkez bankalarının bağımsızlığı araç-amaç bağımsızlığına sıkıştırılır veya bağımsızlık, kökenlerinin tartışıldığı durumlarda para basma yetkisi ile tekeline (senyoraj hakkı) dayandırılır. Merkez bankası bağımsızlaşması ile hukukun üstünlüğü veya hukuk devleti kavramlarının sıkça birlikte kullanıldığı da dikkate alındığında bu tartışmanın daha farklı bir şekilde yapılması gerekmektedir. Bu çalışmada, merkez bankası bağımsızlığı iki koldan; başka bir deyişle birbiri ile ilgili iki süreç olan üstkurullaşma ve finansallaşma süreçleri bakımından ele alınacaktır. Üstkurullaşma süreci, düzenleyici kurulların oluşum süreçleri bakımından geniş bir perspektif sunar ve merkez bankaları özelinde iktisadi işlevin merkez bankası bağımsızlığıyla olan ilişkisini açıklamada yetersiz kaldığı yeri doldurabilir, böylece finansallaşma literatürünün eksikliği tamamlanabilir. Yapmak istediğimiz, merkez bankalarını üstkurullaşma ve yönetişim açısından ele alarak her ne kadar doğrudan bu süreçlerin sonuçları olmasa da ilgili süreçlerin merkez bankalarında yarattığı dönüşümleri ortaya koymaktır. Böylece merkez bankaları üstkurullaşmanın bir parçası ve dolayısıyla hukukun üstünlüğünün modern ölçümlerinin bir parçası olarak sayılabileceğini ve belki de sayıldığını göstermektir
Analytically Explicit Inverse of a Kind of Periodic Tridiagonal Matrix Using a Backward Continued Fraction Approach
No full textWe present a fast algorithm for generating the inverse and the determinant of an extended, periodic, tridiagonal matrix. We use backward continued fractions to generate the elements of the inverse in closed form. By trading memory use against the cost of repeating the computation of certain quantities we are able to produce an effective procedure for a symbolic algebra implementation. We compare the performance of our Maple implementation with that of the standard Maple library procedures for matrix inversion and computation of the determinant on a set of illustrative example matrices. © 2022, Wilmington Scientific Publisher. All rights reserved
Metaverse'de Influencer Pazarlamaya Yönelik Bir İnceleme
No full textMetaverse, which is built on Web 3.0 infrastructure; is described as a decentralized, online fictional virtual universes community that provides integrated and interoperable user experiences, supported by virtual reality applications, where technologies such as blockchain, NFT and cryptocurrencies are frequently used. This new universe, which is representative of the physical world, provides a suitable environment for many online activities such as work, games, education and shopping. At the same time, it creates a more interactive and unlimited market area for global brands with technological innovations, opportunities, and current applications. In this context, it is seen that brands which carry their social media influencer marketing applications to this virtual world develop new marketing activities in terms of influencers which they cooperate with and follower interaction. In this study, the collaborations between the brands that stepped into the Metaverse world and the influencer/meta influencer were examined by making the case study and using Barthes' semiotic analysis method. As a result of the research, it is stated that; in influencer marketing activities on metaverse, posts that visually match the image and the lifestyle of the collaborating influencer have been created, gamification is used in marketing, real-time interaction with followers is enabled in online areas, followers of influencers on their social media accounts were invited to their events on Metaverse, influencer marketing varied experiences are offered by gamification, brands execute strategies in parallel with physical world practices, NFT and Web 3.0 technologies are used, digital products can be marketed and experience marketing has come to the fore in the Metaverse as the current medium of brand and follower interaction. Key Words: Metaverse, Influencer Marketing, Influencer, Meta InfluencerWeb 3.0 alt yapısı üzerine inşa edilen "Metaverse"; blok zinciri, NFT ve kripto para birimleri gibi teknolojilerin sıkça kullanıldığı, sanal gerçeklik uygulamaları ile desteklenen, entegre kullanıcı deneyimleri sunan, birlikte çalışabilir, merkezi olmayan çevrim içi kurgusal sanal evrenler topluluğu olarak açıklanmaktadır. Fiziksel dünyanın bir temsili niteliğindeki bu yeni evren iş, oyun, eğitim ve alışveriş gibi birçok çevrim içi faaliyete uygun ortam sunmakta, beraberinde getireceği teknolojik yenilik, fırsat ve güncel uygulamalar ile global markalar için daha interaktif ve sınırsız bir pazar alanı oluşturmaktadır. Bu bağlamda sosyal medyadaki influencer pazarlama uygulamalarını bu sanal dünyaya taşıyan markaların, iş birliği yaptıkları influencer'lar ve takipçi etkileşimi bakımından yeni pazarlama faaliyetleri geliştirdiği görülmektedir. Bu çalışmada Metaverse dünyasına adım atan markalar ve influencer/meta influencer arasındaki iş birlikleri durum çalışması ve Barthes'ın göstergebilim çözümleme yöntemi kullanılarak incelenmiştir. Araştırma sonucunda, metaverse'de influencer pazarlama faaliyetlerinde, işbirliği yapılan influencer'ın imajı ve yaşam tarzıyla görsel olarak örtüşen paylaşımların oluşturulduğu, pazarlamada oyunlaştırmanın kullanıldığı, takipçilerle çevrim içi alanlarda gerçek zamanlı etkileşimin olanaklı kılındığı, influencer'ların sosyal medya hesaplarındaki takipçilerini Metaverse'deki etkinliklerine davet ettikleri, oyunlaştırmayla farklı deneyimlerin sunulduğu, markaların yaratıcı ve aynı zamanda fiziksel dünyadaki uygulamalarıyla paralel stratejiler yürüttüğü, dijital ürünlerin pazarlandığı, NFT ya da Web 3.0 teknolojisinin kullanıldığı influencer, marka, takipçi etkileşiminin güncel ortamı olarak Metaverse'de deneyim pazarlamasının ön plana çıktığı görülmüştür
Protection of the Environmental Human Rights Defenders for Achieving the Sustainable Development Goals
No full textHuman rights defenders play a key role in the realisation of all human rights. A rights-based approach to planetary boundaries for ensuring a safe and just space for civilisation and humanity requires environmental actions not only from within and across the United Nations system but also from the civil society engaging in the democratic decision-making processes (António Guterres, The Highest Aspiration: A Call to Action for Human Rights, 2020). According to the Declaration on Human Rights Defenders, it is the responsibility of every individual to promote human rights, to safeguard democracy and its institutions. However, exclusion and power imbalances between States, companies, and human rights defenders cause the deterioration of the environmental rule of law, particularly infringing the rights to freedom of peaceful assembly, freedom of association, freedom of expression, and the right to access to justice and effective remedy (A/71/281 Report of the Special Rapporteur on the situation of human rights defenders, 3 August 2016)