cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
SEZIONE V - ARTIVISMO DIGITALE E NET ART
Creators: name: Sansone, Vincenzo
Publisher: name: Connessioni remote. Artivismo_Teatro_Tecnologia
Year: 2021

description: Connessioni remote. Artivismo_Teatro_Tecnologia, Vol 2 No 2 (2021): L’artivismo: forme, esperienze, pratiche e teorie
Anomalous Higgs oscillations mediated by Berry curvature and quantum metric
Creators: name: Villegas, Kristian Hauser A.
name: Yang, Bo
Publisher: name: arXiv
Year: 2020
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Higgs spectroscopy, the study of Higgs bosons of a superconductor, is an emerging field in studying superconductivity. Here we show that the Berry curvature and the quantum metric of bands play a central role in the Higgs mode generation. They allow the detection of Higgs bosons even when the conventional contribution from the band curvature vanishes. Furthermore, we show that the Higgs mode can couple to the external electromagnetic field linearly when mediated by the Berry connection. As a result, we predict the existence of a second harmonic generation, in addition to the well-known third harmonic generation. We elucidate our theory further by considering a flat band superconductor realized by the Harper-Hubbard model and show that the geometric Higgs mode is lower bounded by the band Chern number. We demonstrate in twisted bilayer graphene the existence of the geometrically induced Higgs modes when superconductivity is realized in the nearly flat band at the magic angle.
description: 5 pages + 14 pages Supplemental Material, 4 figures
Roles of peripheral glia in embryonic nervous system development of drosophilia
Creators: name: Sepp, Katharine Julia
Publisher: name: University of British Columbia
Year: 2009

description: Peripheral glial cells are major constituents of the PNS and are required for insulation of peripheral nerves. Their function during Drosophila nervous system development has not been previously studied largely due to a lack o f cellular markers. To determine what roles peripheral glia have in Drosophila embryonic nervous system development, a series of peripheral glial enhancer trap lines were first generated by converting previous glial nuclear lacZ enhancer traps to the GAL4 system. The targeted transposition technique, which is a direct exchange of one P element for another, successfully generated the desired peripheral glial GAL4 lines at a high efficiency. Potentially, targeted transposition is a widely applicable technique for generation of many other desirable GAL4 lines in the future. The new GAL4 lines were used to characterize peripheral glia in relation to neuronal growth. Peripheral glial proliferation, migration, cell contacts, morphological changes, and nerve wrapping were described. Peripheral glia are born at the lateral edge of the CNS. Motor and sensory neurons make physical contacts with the peripheral glia as they migrate across the CNS/PNS border. The peripheral glia then migrate into the PNS along preestablished neuronal tracts while extending long cytoplasmic processes. The peripheral glia completely wrap all sensory axon tracts by the end of embryogenesis, but do not wrap the distal tips of motor neuron branches. The migrational patterns and neuronal associations of peripheral glia during development are very similar to vertebrate glia and suggest that Drosophila may be a powerful model system to understand many aspects of glial development. The GAL4 lines were then used to ablate peripheral glia early in development by ectopic expression of apoptosis genes. The analysis provides insight into the major roles peripheral glia play in generation of the nervous system. Peripheral glia mediate axon migration over the CNS/PNS border and glia are required to prepattern the neuronal CNS exit/entry sites. When the glia are ablated, axons project across the CNS/PNS border at abnormal positions and proper nerve bundling never forms in the region. Peripheral glia also appear to stimulate axogenesis and promote sensory neuron survival. The glia also may provide contact-mediated cues for centrally directed sensory axon migration. Peripheral glia are also essential for maintenance of tight axon fasciculation and compact nerve bundling. Overall, the results suggest that peripheral glia have important functions in early and late development of the nervous system which also may be common to vertebrate PNS glia.
Non più arte, solo vita. 4.0. Dall’artivismo simulativo alle tattiche di soppiantamento nella rete
Creators: name: Baigorri, Laura
Publisher: name: Connessioni remote. Artivismo_Teatro_Tecnologia
Year: 2021

description: I progetti artistici di natura attivista che trovano esecuzione su internet sono solitamente simulatori, fanno appello fondamentalmente alla riflessione e modificano poco o nulla della vita delle persone interessate. Sebbene ci sianoanche alcune proposte artiviste che sono riuscite a intervenire sulla realtà e a cambiare i fatti, a volte grazie allepotenzialità comunicative della rete, altre perché il contesto dell’arte ha fermato i colpi... ma questa posizionerichiede un equilibrio che è sempre più difficile da mantenere. Quali sono i vantaggi e gli svantaggi dello sviluppo di progetti attivisti nel campo dell'arte? Questo testo solleva una riflessione su questa questione attraverso l’analisi deilavori paradigmatici dei primi collettivi artistici attivisti che utilizzarono internet alla fine degli anni Novanta: Critical Art Ensemble (CAE) con Flesh Machine e Free Range Grains, EDT. The Electronic Disturbance Theatre con Swarm, rtmark con Voteauction, 01.org (Franco e Eva Mattes) con Nikeground, Etoy.com con Toy war.
description: Connessioni remote. Artivismo_Teatro_Tecnologia, Vol 2 No 2 (2021): L’artivismo: forme, esperienze, pratiche e teorie
Observation of Bifurcations and Hysteresis in Nonlinear NbN Superconducting Microwave Resonators
Creators: name: Abdo, Baleegh
name: Segev, Eran
name: Shtempluck, Oleg
name: Buks, Eyal
Publisher: name: arXiv
Year: 2005
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: In this paper we report some extraordinary nonlinear dynamics measured in the resonance curve of NbN superconducting stripline microwave resonators. Among the nonlinearities observed: aburpt bifurcations in the resonance response at relatively low input powers, asymmetric resonances, multiple jumps within the resonance band, resonance frequency drift, frequency hysteresis, hysteresis loops changing direction and critical coupling phenomenon. Weak links in the NbN grain structure are hypothesized as the source of the nonlinearities.
description: This work has been submitted to the IEEE for possible publication
Graph Unrolling Networks: Interpretable Neural Networks for Graph Signal Denoising
Creators: name: Chen, Siheng
name: Eldar, Yonina C.
name: Zhao, Lingxiao
Publisher: name: arXiv
Year: 2020
Subjects: subject: Signal Processing (eess.SP)
subject: Social and Information Networks (cs.SI)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: We propose an interpretable graph neural network framework to denoise single or multiple noisy graph signals. The proposed graph unrolling networks expand algorithm unrolling to the graph domain and provide an interpretation of the architecture design from a signal processing perspective. We unroll an iterative denoising algorithm by mapping each iteration into a single network layer where the feed-forward process is equivalent to iteratively denoising graph signals. We train the graph unrolling networks through unsupervised learning, where the input noisy graph signals are used to supervise the networks. By leveraging the learning ability of neural networks, we adaptively capture appropriate priors from input noisy graph signals, instead of manually choosing signal priors. A core component of graph unrolling networks is the edge-weight-sharing graph convolution operation, which parameterizes each edge weight by a trainable kernel function where the trainable parameters are shared by all the edges. The proposed convolution is permutation-equivariant and can flexibly adjust the edge weights to various graph signals. We then consider two special cases of this class of networks, graph unrolling sparse coding (GUSC) and graph unrolling trend filtering (GUTF), by unrolling sparse coding and trend filtering, respectively. To validate the proposed methods, we conduct extensive experiments on both real-world datasets and simulated datasets, and demonstrate that our methods have smaller denoising errors than conventional denoising algorithms and state-of-the-art graph neural networks. For denoising a single smooth graph signal, the normalized mean square error of the proposed networks is around 40% and 60% lower than that of graph Laplacian denoising and graph wavelets, respectively.
Amplitudes of minima in dynamic conductance spectra of the SNS Andreev contact
Creators: name: Popovic, Z.
name: Kuzmichev, S.
name: Kuzmicheva, T.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Despite several theoretical approaches describing multiple Andreev reflections (MAR) effect in superconductor-normal metal-superconductor (SNS) junction are elaborated, the problem of comprehensive and adequate description of MAR is highly actual. In particular, a broadening parameter $Γ$ is still unaccounted at all, whereas a ballistic condition (the mean free path for inelastic scattering $l$ to the barrier width $d$ ratio) is considered only in the framework of Kümmel, Gunsenheimer, and Nikolsky (KGN), as well as Gunsenheimer-Zaikin approaches, for an isotropic case and fully-transparent constriction. Nonetheless, an influence of $l/d$ ratio to the dynamic conductance spectrum ($dI/dV$) features remains disregarded, thus being one of the aims of the current work. Our numerical calculations in the framework of an extended KGN approach develop the $l/d$ variation to determine both the number of the Andreev features and their amplitudes in the $dI/dV$ spectrum. We show, in the spectrum of a diffusive SNS junction ($l/d \rightarrow 1$) a suppression of the Andreev excess current, dramatic change in the current voltage $I(V)$-curve slope at low bias, with only the main harmonic at $eV=2Δ$ bias voltage remains well-distinguished in the $dI/dV$-spectrum. Additionally, we attempt to make a first-ever comparison between experimental data for the high-transparency SNS junctions (more than $ 85~\%$) and theoretical predictions. As a result, we calculate the temperature dependences of amplitudes and areas of Andreev features within the extended KGN approach, which qualitatively agrees with our experimental data obtained using a "break-junction" technique.
description: 9 pages, 8 figures
Per una salvezza ubiqua. Una riflessione “artivista” tra tecnologia e cura
Creators: name: Cipolletta, Giorgio
Publisher: name: Connessioni remote. Artivismo_Teatro_Tecnologia
Year: 2021

description: Nell'ultimo secolo i progressi della tecnologia applicata alla biologia, alla robotica, alle neuroscienze sono confluite nel paesaggio algoritmico “liberando” spazi di ibridazione e contaminazione. Le arti multimediali, e le nuove pratiche artistiche hanno rimesso in discussione alcuni assiomi storici, come il concetto di autorialità e di unicità dell’opera. Si apre un “futuro anteriore" di comunicazione, di connessione, sempre più esteso e pronto a consegnarci un immaginario collettivo capace di interpretare cambiamenti epocali. L’arte tecnologica e le sue sperimentazioni hanno “attivato” nello sguardo caleidoscopio dell’arte un’azione performativa connettiva dove arte, vita e politica si integrano in una “battaglia” tra processi di democratizzazione della rete e dell’informazione e mediata da corpi “liberati”. Questa è una storia di tante storie possibili, dove la cura assolve la sua funzione nella connessione fra media e vissuto amplificato dalla pratica artistica di un "Nuovo Abitare" per una cultura ecosistemica. Il corpo-dispositivo con tutte le sue possibilità si dissemina nella rete, reinventando il reale e la malattia e creando spazi “aumentati” per la critica, per l’espressione, per l’azione e per una “salvezza ubiqua”. La grande opportunità dell’esistenza è quella di esprimersi “po(i)eticamente” attraverso i dati per generare un dibattito esistenziale nella cultura.
description: Connessioni remote. Artivismo_Teatro_Tecnologia, Vol 2 No 2 (2021): L’artivismo: forme, esperienze, pratiche e teorie
Realizing homology classes by symplectic submanifolds
Creators: name: Le, Hong-Van
Publisher: name: arXiv
Year: 2005
Subjects: subject: Symplectic Geometry (math.SG)
subject: FOS: Mathematics

description: In this note we prove that a positive multiple of each even-dimensional integral homology class of a compact symplectic manifold $(M^{2n}, ω)$ can be represented as the difference of the fundamental classes of two symplectic submanifolds in $(M^{2n}, ω)$. We also discuss the realizability of integral homology classes by symplectic surfaces in $(M^{2n}, ω)$.
description: 10 pages, final version
SEZIONE I - TEORIA, ARTIVISMO, ARTE PARTECIPATIVA
Creators: name: Sansone, Vincenzo
Publisher: name: Connessioni remote. Artivismo_Teatro_Tecnologia
Year: 2021

description: Connessioni remote. Artivismo_Teatro_Tecnologia, Vol 2 No 2 (2021): L’artivismo: forme, esperienze, pratiche e teorie
An extensive study of dynamical friction in dwarf galaxies: the role of stars, dark matter, halo profiles and MOND
Creators: name: Sanchez-Salcedo, F. J.
name: Reyes-Iturbide, Jorge
name: Hernandez, X.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We investigate the in-spiraling timescales of globular clusters in dwarf spheroidal (dSph) and dwarf elliptical (dE) galaxies, due to dynamical friction. We address the problem of these timescales having been variously estimated in the literature as much shorter than a Hubble time. Using self-consistent two-component (dark matter and stars) models, we explore mechanisms which may yield extended dynamical friction timescales in such systems in order to explain why dwarf galaxies often show globular cluster systems. As a general rule, dark matter and stars both give a comparable contribution to the dynamical drag. By exploring various possibilities for their gravitational make-up, it is shown that these studies help constrain the parameters of the dark matter haloes in these galaxies, as well as to test alternatives to dark matter. Under the assumption of a dark haloes having a constant density core, dynamical friction timescales are naturally extended upwards of a Hubble time. Cuspy dark haloes yield timescales $\lesssim$ 4.5 Gyr, for any dark halo parameters in accordance with observations of stellar line-of-sight velocity dispersion in dwarf spheroidal galaxies. We find that under the hypothesis of MOND dynamics, due to the enhanced dynamical drag of the stars, the dynamical friction timescales would be extremely short. Taking the well-measured structural parameters of the Fornax dSph and its globular cluster system as a case study, we conclude that requiring dynamical friction timescales comparable to the Hubble time strongly favours dark haloes with a central core.
description: 18 pages, four figures, final version, accepted in MNRAS
Generalized Ito Formulae and Space-Time Lebesgue-Stieltjes Integrals of Local Times
Creators: name: Elworthy, K. D.
name: Truman, A.
name: Zhao, H. Z.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60H05, 60H30

description: Generalised Ito formulae are proved for time dependent functions of continuous real valued semi-martingales. The conditions involve left space and time first derivatives, with the left space derivative required to have locally bounded 2-dimensional variation. In particular a class of functions with discontinuous first derivative is included. An estimate of Krylov allows further weakening of these conditions when the semi-martingale is a diffusion.
SEZIONE IV - I LUOGHI DELL'ARTIVISMO
Creators: name: Sansone, Vincenzo
Publisher: name: Connessioni remote. Artivismo_Teatro_Tecnologia
Year: 2021

description: Connessioni remote. Artivismo_Teatro_Tecnologia, Vol 2 No 2 (2021): L’artivismo: forme, esperienze, pratiche e teorie
Rapid variability of the arcsec-scale X-ray jets of SS 433
Creators: name: Migliari, S.
name: Fender, R. P.
name: Blundell, K. M.
name: Mendez, M.
name: van der Klis, M.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present the X-ray images of all the available Chandra observations of the galactic jet source SS 433. We have studied the morphology of the X-ray images and inspected the evolution of the arcsec X-ray jets, recently found to be manifestations of in situ reheating of the relativistic gas downstream in the jets. The Chandra images reveal that the arcsec X-ray jets are not steady long term structures; the structure varies, indicating that the reheating processes have no preference for a particular precession phase or distance from the binary core. Three observations made within about five days in May 2001, and a 60 ks observation made in July 2003 show that the variability of the jets can be very rapid, from timescales of days to (possibly) hours. The three May 2001 images show two resolved knots in the east jet getting brighter one after the other, suggesting that a common phenomenon might be at the origin of the sequential reheatings of the knots. We discuss possible scenarios and propose a model to interpret these brightenings in terms of a propagating shock wave, revealing a second, faster outflow in the jet.
description: accepted for publication in MNRAS
Application of Blockchain and Internet of Things to Ensure Tamper-Proof Data Availability for Food Safety
Creators: name: Iftekhar, Adnan
name: Cui, Xiaohui
name: Hassan, Mir
name: Afzal, Wasif
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computers and Society (cs.CY)
subject: FOS: Computer and information sciences

description: Food supply chain plays a vital role in human health and food prices. Food supply chain inefficiencies in terms of unfair competition and lack of regulations directly affect the quality of human life and increase food safety risks. This work merges Hyperledger Fabric, an enterprise-ready blockchain platform with existing conventional infrastructure, to trace a food package from farm to fork using an identity unique for each food package while keeping it uncomplicated. It keeps the records of business transactions that are secured and accessible to stakeholders according to the agreed set of policies and rules without involving any centralized authority. This paper focuses on exploring and building an uncomplicated, low-cost solution to quickly link the existing food industry at different geographical locations in a chain to track and trace the food in the market.
description: Journal of Food Quality, 2020
Aname savanella
Creators: name: Wilson, Jeremy D.
name: Harvey, Mark S.
name: Simmons, Leigh W.
name: Rix, Michael G.
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Anamidae
Aname
Aname savanella

description: Aname savanella -complex
Figs 4E, 13, 103–104
Composition
The savanella- complex includes two described species: A. cudmore sp. nov. and A. savannella sp. nov.
description: Published as part of Wilson, Jeremy D., Harvey, Mark S., Simmons, Leigh W. & Rix, Michael G., 2025, An integrative systematic revision of the wishbone spiders (Araneae: Anamidae: Aname L. Koch, 1873) of subtropical and tropical eastern Australia, with the description of 55 new species, pp. 1-298 in European Journal of Taxonomy 985 on page 161, DOI: 10.5852/ejt.2025.985.2845, http://zenodo.org/record/15169471
Statistical Mechanics of Online Learning for Ensemble Teachers
Creators: name: Miyoshi, Seiji
name: Okada, Masato
Publisher: name: arXiv
Year: 2006
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We analyze the generalization performance of a student in a model composed of linear perceptrons: a true teacher, ensemble teachers, and the student. Calculating the generalization error of the student analytically using statistical mechanics in the framework of on-line learning, it is proven that when learning rate $η<1$, the larger the number $K$ and the variety of the ensemble teachers are, the smaller the generalization error is. On the other hand, when $η>1$, the properties are completely reversed. If the variety of the ensemble teachers is rich enough, the direction cosine between the true teacher and the student becomes unity in the limit of $η\to 0$ and $K \to \infty$.
description: 11 pages, 9 figures
Copertina del numero 2, comitato editoriale e comitato scientifico
Creators: name: Sansone, Vincenzo
Publisher: name: Connessioni remote. Artivismo_Teatro_Tecnologia
Year: 2021

description: Connessioni remote. Artivismo_Teatro_Tecnologia, Vol 2 No 2 (2021): L’artivismo: forme, esperienze, pratiche e teorie
Eye Movements Biometrics: A Bibliometric Analysis from 2004 to 2019
Creators: name: Brasil, Antonio Ricardo Alexandre
name: Andrade, Jefferson Oliveira
name: Komati, Karin Satie
Publisher: name: arXiv
Year: 2020
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Digital Libraries (cs.DL)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences
subject: A.1; H.5; I.5

description: Person identification based on eye movements is getting more and more attention, as it is anti-spoofing resistant and can be useful for continuous authentication. Therefore, it is noteworthy for researchers to know who and what is relevant in the field, including authors, journals, conferences, and institutions. This paper presents a comprehensive quantitative overview of the field of eye movement biometrics using a bibliometric approach. All data and analyses are based on documents written in English published between 2004 and 2019. Scopus was used to perform information retrieval. This research focused on temporal evolution, leading authors, most cited papers, leading journals, competitions and collaboration networks.
description: 9 pages, 2 figures, journal
New reals: Can live with them, can live without them
Creators: name: Goldstern, Martin
name: Kellner, Jakob
Publisher: name: arXiv
Year: 2005
Subjects: subject: Logic (math.LO)
subject: FOS: Mathematics
subject: 03E40, 03E17

description: We give a self-contained proof of the preservation theorem for proper countable support iterations known as "tools-preservation," "Case A" or "first preservation theorem" in the literature. We do not assume that the forcings add reals.
description: (an incorrect claim following Fact 2.3 was removed)
Elliptical instability of a flow in a rotating shell
Creators: name: Lacaze, L.
name: Gal, P. Le
name: Dizès, S. Le
Publisher: name: arXiv
Year: 2005
Subjects: subject: Classical Physics (physics.class-ph)
subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: A theoretical and experimental study of the spin-over mode induced by the elliptical instability of a flow contained in a slightly deformed rotating spherical shell is presented. This geometrical configuration mimics the liquid rotating cores of planets when deformed by tides coming from neighboring gravitational bodies. Theoretical estimations for the growth rates and for the non linear amplitude saturations of the unstable mode are obtained and compared to experimental data obtained from Laser Döppler anemometry measurements. Visualizations and descriptions of the various characteristics of the instability are given as functions of the flow parameter.
Researching Artivism through the Event Approach. Epistemological and Methodological Reflections about Art and Activism
Creators: name: Salzbrunn, Monika
Publisher: name: Connessioni remote. Artivismo_Teatro_Tecnologia
Year: 2021

description: The ERC ARTIVISM project focuses on various art forms used by activists in order to formulate political claims. From a multisensory perspective, creativity and performance as subversive forms of political expression are researched in super-diverse cities on three continents (Douala and Yaoundé in Cameroon, Los Angeles in the United States of America, Genova and Viareggio in Italy and Nice and Marseille in France). Applying the event approach instead of a group-centred perspective, the team has elaborated on methods of apprenticeship, field-crossing and audio-visual anthropology (filming, drawing). Preliminary results indicate the growing importance of speculation, touristification and city-marketing as targets chosen by activists who organise independent carnival and carnivalesquepolitical performances in a context of securisation, control and censorship.
description: Connessioni remote. Artivismo_Teatro_Tecnologia, Vol 2 No 2 (2021): L’artivismo: forme, esperienze, pratiche e teorie
In situ Imaging of Precipitate Formation in Additively Manufactured Al-Alloys by Scanning X-ray Fluorescence
Creators: name: Lazar, Isac
name: Mehta, Bharat
name: Bertschová, Vendulka
name: Malladi, Sri Bala Aditya
name: Ren, Zhe
name: Das, Srashtasrita
name: Hagemann, Johannes
name: Falkenberg, Gerald
name: Frisk, Karin
name: Mikkelsen, Anders
name: Nyborg, Lars
Publisher: name: Deutsches Elektronen-Synchrotron, DESY, Hamburg
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: doi:10.48550/ARXIV.2311.14529
description: A new family of high-strength Al-alloys has recently been developed, tailored for the powder bed fusion-laser beam process. In these alloys, Mn, Cr and Zr are incorporated in solid solution at amounts up to three times that of equilibrium in the as-printed state. Mn and Cr-enriched precipitates that form during printing and heat treatment influence the material's mechanical properties. In this study, direct imaging of these precipitates was accomplished through the utilisation of in situ synchrotron-based scanning X-ray fluorescence. During heat treatment, a selective accumulation of Cr and Mn in two distinct types of precipitates at grain boundaries was observed. Additionally, the microstructure at the melt-pool boundary, containing precipitates found in the as-printed state, remains thermally stable during the heat treatment. The study demonstrates the significant value of employing high-sensitivity in-situ X-ray fluorescence microscopy in exploring the kinetics of sub-micrometre scale precipitation.
Composite Enclaves: Towards Disaggregated Trusted Execution
Creators: name: Schneider, Moritz
name: Dhar, Aritra
name: Puddu, Ivan
name: Kostiainen, Kari
name: Capkun, Srdjan
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cryptography and Security (cs.CR)
subject: Hardware Architecture (cs.AR)
subject: FOS: Computer and information sciences

description: The ever-rising computation demand is forcing the move from the CPU to heterogeneous specialized hardware, which is readily available across modern datacenters through disaggregated infrastructure. On the other hand, trusted execution environments (TEEs), one of the most promising recent developments in hardware security, can only protect code confined in the CPU, limiting TEEs' potential and applicability to a handful of applications. We observe that the TEEs' hardware trusted computing base (TCB) is fixed at design time, which in practice leads to using untrusted software to employ peripherals in TEEs. Based on this observation, we propose \emph{composite enclaves} with a configurable hardware and software TCB, allowing enclaves access to multiple computing and IO resources. Finally, we present two case studies of composite enclaves: i) an FPGA platform based on RISC-V Keystone connected to emulated peripherals and sensors, and ii) a large-scale accelerator. These case studies showcase a flexible but small TCB (2.5 KLoC for IO peripherals and drivers), with a low-performance overhead (only around 220 additional cycles for a context switch), thus demonstrating the feasibility of our approach and showing that it can work with a wide range of specialized hardware.
Εντοπισμός μοτίβων σε οικονομικά δεδομένα και ανάπτυξη στρατηγικής χαρτοφυλακίου
Creators: name: Φωτιάδης, Άρης Χαράλαμπος Ιωάννη
Publisher: name: Aristotle University of Thessaloniki
Year: 2023
Subjects: Μηχανική Μάθηση
Χρονοσειρές
Μετοχές
Machine Learning
Time-Series
Stocks

description: Οι παρελθούσες τιμές αποτελούν μία συνιστώσα της μελλοντικής κίνησης της τιμής των μετοχών. Ποια θα είναι η θρυαλλίδα που θα πυροδοτήσει την άνοδο ή την πτώση δεν μπορεί να είναι γνωστό εκ των προτέρων. Η γνώση όμως του πως αντέδρασαν οι τιμές σε παρόμοιες καταστάσεις του παρελθόντος μπορεί να αξιοποιηθεί για την αποτελεσματική αναγνώριση και πρόβλεψη των εξελίξεων. Σκοπός της διπλωματικής εργασίας είναι ο εντοπισμός μοτίβων στη χρονοσειρά οικονομικών δεδομένων της αγοράς αξιών με τη βοήθεια της Μηχανικής Μάθησης και συγκεκριμένα των αλγορίθμων ομαδοποίησης. Τα μοτίβα που επιλέχθηκαν μετασχημάτισαν τη χρονοσειρά τιμών σε μια ακολουθία μοτίβων. Αξιοποιώντας στοιχεία τεχνικής ανάλυσης και την σειρά των μοτίβων εκπαιδεύτηκαν μοντέλα επιβλεπόμενης Μηχανικής Μάθησης με σκοπό την πρόβλεψη ενός επόμενου μοτίβου βάσει των προηγούμενων και των πληροφοριών της τεχνικής ανάλυσης για την τάση αυτού. Τα αποτελέσματα των προβλέψεων χρησιμοποιήθηκαν για την διαμόρφωση κερδοφόρας στρατηγικής, η οποία εφαρμόστηκε αποτελεσματικά σε τρία χαρτοφυλάκια μετοχών.
description: Past prices are a component of future stock price movement. What will be the fuse that will trigger their rise or fall cannot be known in advance. However, the knowledge of how prices reacted to similar situations in the past, can be used to effectively identify and predict developments. The purpose of this thesis is to identify patterns in the time series of financial data from the stock market, with the help of Machine Learning and specifically of clustering algorithms. The selected patterns transformed the price time series into a sequence of patterns. Utilizing technical analysis data and pattern sequence, supervised Machine Learning models were trained to predict a following pattern based on previous patterns and technical analysis information on its trend. The results of the forecasts were used to formulate a profitable strategy, which was effectively applied to three portfolios, each consisted of a pool of stocks.
Theory of optical imaging beyond the diffraction limit with a far-field superlens
Creators: name: Durant, Stephane
name: Liu, Zhaowei
name: Fang, Nicholas
name: Zhang, Xiang
Publisher: name: arXiv
Year: 2006
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Recent theoretical and experimental studies have shown that imaging with resolution well beyond the diffraction limit can be obtained with so-called superlenses. Images formed by such superlenses are, however, in the near field only, or a fraction of wavelength away from the lens. In this paper, we propose a far-field superlens (FSL) device which is composed of a planar superlens with periodical corrugation. We show in theory that when an object is placed in close proximity of such a FSL, a unique image can be formed in far-field. As an example, we demonstrate numerically that images of 40 nm lines with a 30 nm gap can be obtained from far-field data with properly designed FSL working at 376nm wavelength.
description: 6 pages, 3 figures
title: DUEIT Ausgabe 09 (April 2019)
Creators: name: Universität  / Universitätsbibliothek
name: Universität  / Zentrum Für Informations- Und Mediendienste
Publisher: name: DuEPublico: Duisburg-Essen Publications Online, University of Duisburg-Essen, Germany
Year: 2019

description: INHALT
 Interview mit dem IKM-Vorstand Editorial Angebote von Softwareprodukten Das Eduroam 4. E-Learning-Netzwerktag an der UDE UDE-Webrelaunch Girls´Day 2019 Informationssicherheit Verhandlungserfolg bei DEAL „Lernende brauchen Raum...“ Unpaywall Zusammen stark: Open Access Aurora News
Complex structure on the six dimensional sphere from a spontaneous symmetry breaking
Creators: name: Etesi, Gabor
Publisher: name: arXiv
Year: 2005
Subjects: subject: Differential Geometry (math.DG)
subject: High Energy Physics - Theory (hep-th)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 32J17 (Primary), 32J25, 43A30 (Secondary), 53C56, 81T13

description: Existence of a complex structure on the $6$ dimensional sphere is proved in this paper. The proof is based on re-interpreting a hypothetical complex structure as a classical ground state of a Yang--Mills--Higgs-like theory on $S^6$. This classical vacuum solution is then constructed by Fourier expansion (dimensional reduction) from the obvious one of a similar theory on the $14$ dimensional exceptional compact Lie group ${\rm G}_2$.
description: 26 pages, LaTeX, no figures; the published version with a correction
Focus group discussion guide
Creators: name: Ndejjo, Rawlance
Publisher: name: figshare
Year: 2021
Subjects: subject: 111799 Public Health and Health Services not elsewhere classified
subject: FOS: Health sciences

description: Focus group discussion guide for the study titled Hypertension and diabetes patients’ perspective of challenges and their coping mechanisms in Mukono and Buikwe districts in Uganda – a qualitative study
The critical region of strong-coupling lattice QCD in different large-N limits
Creators: name: Bringoltz, Barak
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the critical behavior at nonzero temperature phase transitions of an effective Hamiltonian derived from lattice QCD in the strong-coupling expansion. Following studies of related quantum spin systems that have a similar Hamiltonian, we show that for large $N_c$ and fixed $g^2N_c$, mean field scaling is not expected, and that the critical region has a finite width at $N_c=\infty$. A different behavior rises for $N_f\to \infty$ and fixed $N_c$ and $g^2/N_f$, which we study in two spatial dimensions and for $N_c=1$. We find that the width of the critical region is suppressed by $1/N_f^p$ with $p=1/2$, and argue that a generalization to $N_c>1$ and to three dimensions will change this only in detail (e.g. the value of $p>0$), but not in principle. We conclude by stating under what conditions this suppression is expected, and remark on possible realizations of this phenomenon in lattice gauge theories in the continuum.
description: 24 pages, 6 figures. New version includes: a more extensive discussion of strong-coupling expansions and their region of validity. Accordingly I have reworded the descriptions of the investigated limits. Removed typos and misprints
Numerical continuation of spiral waves in heteroclinic networks of cyclic dominance
Creators: name: Hasan, Cris R.
name: Osinga, Hinke M.
name: Postlethwaite, Claire M.
name: Rucklidge, Alastair M.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Analysis of PDEs (math.AP)
subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics

description: Heteroclinic-induced spiral waves may arise in systems of partial differential equations that exhibit robust heteroclinic cycles between spatially uniform equilibria. Robust heteroclinic cycles arise naturally in systems with invariant subspaces and their robustness is considered with respect to perturbations that preserve these invariances. We make use of particular symmetries in the system to formulate a relatively low-dimensional spatial two-point boundary-value problem in Fourier space that can be solved efficiently in conjunction with numerical continuation. The standard numerical set-up is formulated on an annulus with small inner radius, and Neumann boundary conditions are used on both inner and outer radial boundaries. We derive and implement alternative boundary conditions that allow for continuing the inner radius to zero and so compute spiral waves on a full disk. As our primary example, we investigate the formation of heteroclinic-induced spiral waves in a reaction-diffusion model that describes the spatiotemporal evolution of three competing populations in a two-dimensional spatial domain--much like the Rock-Paper-Scissors game. We further illustrate the efficiency of our method with the computation of spiral waves in a larger network of cyclic dominance between five competing species, which describes the so-called Rock-Paper-Scissors-Lizard-Spock game.
On environment-assisted capacities of quantum channels
Creators: name: Winter, Andreas
Publisher: name: arXiv
Year: 2005
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Following initial work by Gregoratti and Werner [J. Mod. Optics 50, 913-933, 2003 and quant-ph/0403092] and Hayden and King [quant-ph/0409026], we study the problem of the capacity of a quantum channel assisted by a "friendly (channel) environment" that can locally measure and communicate classical messages to the receiver. Previous work [quant-ph/0505038] has yielded a capacity formula for the quantum capacity under this kind of help from the environment. Here we study the problem of the environment-assisted classical capacity, which exhibits a somewhat richer structure (at least, it seems to be the harder problem). There are several, presumably inequivalent, models of the permitted local operations and classical communications between receiver and environment: one-way, arbitrary, separable and PPT POVMs. In all these models, the task of decoding a message amounts to discriminating a set of possibly entangled states between the two receivers, by a class of operations under some sort of locality constraint. After introducing the operational capacities outlined above, we show that a lower bound on the environment-assisted classical capacity is always half the logarithm of the input space dimension. Then we develop a few techniques to prove the existence of channels which meet this lower bound up to terms of much smaller order, even when PPT decoding measurements are allowed (assuming a certain superadditivity conjecture).
description: 9 pages revtex4, 1 stolen figure (eps)
Mixing in manipulated turbulence
Creators: name: Kuczaj, Arkadiusz K.
name: Geurts, Bernard J.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: A new computational framework for the simulation of turbulent flow through complex objects and along irregular boundaries is presented. This is motivated by the application of metal foams in compact heat-transfer devices, or as catalyst substrates in process-engineering. The flow-consequences of such complicated objects are incorporated by adding explicit multiscale forcing to the Navier-Stokes equations. The forcing represents the simultaneous agitation of a wide spectrum of length-scales when flow passes through the complex object. It is found that a considerable modulation of the traditional energy cascading can be introduced with a specific forcing strategy. In spectral space, forcing yields strongly localized deviations from the common Kolmogorov scaling law, directly associated with the explicitly forced scales. In addition, the accumulated effect of forcing induces a significant non-local alteration of the kinetic energy including the spectrum for the large scales. Consequently, a manipulation of turbulent flow can be achieved over an extended range, well beyond the directly forced scales. The turbulent mixing of a passive scalar field is also investigated, in order to quantify the physical-space modifications of transport processes in multiscale forced turbulence. The surface-area and wrinkling of level-sets of the scalar field are monitored as measures of the influence of explicit forcing on the local and global mixing efficiency.
description: submitted to Journal of Turbulence, 35 pages, 13 figures
Hampe, Johann Christoph (Hrsg.), Die Authorität der Freiheit
Creators: name: Lell, Joachim
Publisher: name: Ökumenische Rundschau
Year: 2025

description: Ökumenische Rundschau, Bd. 16 Nr. 3 (1967): Ökumenische Rundschau, Band 16, Heft 3
Two-hadron single target-spin asymmetries: first measurement by HERMES
Creators: name: van der Nat, P. B.
name: Griffioen, K.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Single target-spin asymmetries in semi-inclusive two-pion production were measured for the first time by the HERMES experiment, using a longitudinally polarized deuterium target. These asymmetries relate to the unknown transversity distribution function $h_1(x)$ through, also unknown, interference fragmentation functions. The presented results are compared with a model for the dependence of one of these interference fragmentation functions on the invariant mass of the pion pair.
description: 4 pages, 4 figures, contribution to the proceedings for the 16th international spin physics symposium (SPIN'2004)
ARE WE STILL INVESTING IN SOUTH AFRICAN AGRICULTURE: PERCEPTIONS, EVIDENCE AND ANALYSIS
Creators: name: Esterhuizen, Dirk
name: Van Rooyen, C.J.
name: Doyer, Ockert T.
name: Esterhuizen, Dirk
name: Van Rooyen, C.J.
name: Doyer, Ockert T.
Publisher: name: Unknown
Year: 2001
Subjects: Agricultural and Food Policy

description: In this paper the question of investment in the South African agro-food and fibre complex is explored. The analysis is based on empirical values and opinions/perceptions from ±400 agribusinesses operating in this complex. From the analysis it is clear that decisions to invest in the agro-food and fibre complex in South Africa must be viewed as on "knife-edge". A range of recommendations and policy options will be required to activate investment drivers and to address constraints in order to stimulate investment and to achieve growth.
Khintchine type inequalities for reduced free products and Applications
Creators: name: Ricard, Eric
name: Xu, Quanhua
Publisher: name: arXiv
Year: 2005
Subjects: subject: Operator Algebras (math.OA)
subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: Primary 46L09, 46L54, Secondary 47L07, 47L25

description: We prove Khintchine type inequalities for words of a fixed length in a reduced free product of $C^*$-algebras (or von Neumann algebras). These inequalities imply that the natural projection from a reduced free product onto the subspace generated by the words of a fixed length $d$ is completely bounded with norm depending linearly on $d$. We then apply these results to various approximation properties on reduced free products. As a first application, we give a quick proof of Dykema's theorem on the stability of exactness under the reduced free product for $C^*$-algebras. We next study the stability of the completely contractive approximation property (CCAP) under reduced free product. Our first result in this direction is that a reduced free product of finite dimensional $C^*$-algebras has the CCAP. The second one asserts that a von Neumann reduced free product of injective von Neumann algebras has the weak-$*$ CCAP. In the case of group $C^*$-algebras, we show that a free product of weakly amenable groups with constant 1 is weakly amenable.
Αξιολόγηση της διατήρησης του δεσμού ενός CAD/CAM κεραμικού υλικού με ρητινώδη μήτρα με την οδοντίνη μετά από τροποποίηση της επιφάνειας του με διάφορες τεχνικές
Creators: name: Γαλανόπουλος, Αλέξανδρος Αλεξίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2023
Subjects: Διεπαφή υλικού/οδοντίνης
Τεχνητή γήρανση
Επιφανειακή επεξεργασία υλικού
Microgap formation
Artificial aging
Surface treatment

description: Σκοπός της διπλωματικής εργασίας είναι η αξιολόγηση της διεπαφής μεταξύ οδοντίνης και υβριδικής ρητίνης κατασκευασμένης στο CAD/CAM, ύστερα από διαφορετικούς τρόπους επεξεργασίας του υλικού και τεχνητή γήρανση. Για τη μέτρηση της διεπαφής και της επιφανειακής επεξεργασίας τα δοκίμια χωρίστηκαν σε 5 πειραματικές ομάδες (n=5) . Όλα τα δοκίμια υποβλήθηκαν σε τεχνητή γήρανση 5000 κύκλων και αυξομείωση θερμοκρασιών μεταξύ 5°C και 55°C. Για τις ανάγκες της στατιστικής χρησιμοποιήθηκε το λογισμικό SPSS 24.0. Εξετάζοντας τις λήψεις από το ηλεκτρονικό μικροσκόπιο SEM βλέπουμε διαφορές στην επιφάνεια του υλικού της κάθε πειραματικής ομάδας μετά την εκάστοτε επεξεργασία, η οποία επηρεάζει την διεπαφή υλικού/οδοντίνης. Σύμφωνα λοιπόν και με τους περιορισμούς αυτής της έρευνας, θα μπορούσε να καταλήξει κανείς στο συμπέρασμα ότι οι επιφανειακές τροποποιήσεις ενός υβριδικού υλικού CAD/CAM μπορούν να επηρεάσουν το σχηματισμό μικροκενού στη διεπαφή κονίας/αποκαταστάσεων, πιθανώς λόγω διαφορών στην απόδοση συγκόλλησης. Η μηχανική επιφανειακή επεξεργασία με χρήση αεροαποτριβής με σωματίδια Al2O3 παρουσίασε μικρότερο σχηματισμό μικροκενού σε σύγκριση με τις άλλες επεξεργασίες. Η ομάδα που υποβλήθηκε σε θεραπεία με laserEr,Cr:YSGG έδειξε παρόμοιο σχηματισμό μικροκενού με την ομάδα ελέγχου.
description: The purpose of the study is to evaluate the interface between dentin and hybrid resin manufactured in CAD/CAM, after different ways of processing the material and artificial aging. To measure the interface and surface treatment the samples were divided into 5 experimental groups (n=5). All samples were subjected to 5000 cycles of artificial aging and temperature fluctuations between 5°C and 55°C. SPSS 24.0 software was used for statistical purposes. Examining the images from the electron microscope SEM we see differences in the material surface of each experimental group after each treatment, which affects the material/dentin interface. According to the limitations of this research, we could conclude that surface modifications of a CAD/CAM hybrid material can affect microgap formation at the cement/restoration interface, possibly due to differences in bonding performance. Mechanical surface treatment using air abrasion with Al2O3 particles showed less microgap formation compared to the other treatments. The group treated with laser Er,Cr:YSGG showed similar microgap formation to the control group.