cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Inequivalent quantizations from gradings and ${\mathbb Z}_2\times {\mathbb Z}_2$ parabosons
Creators: name: Toppan, Francesco
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: This paper introduces the parastatistics induced by ${\mathbb Z}_2\times {\mathbb Z}_2$-graded algebras. It accommodates four kinds of particles: ordinary bosons and three types of parabosons which mutually anticommute when belonging to different type (so far, in the literature, only parastatistics induced by ${\mathbb Z}_2\times {\mathbb Z}_2$-graded superalgebras and producing parafermions have been considered). It is shown how to detect ${\mathbb Z}_2\times {\mathbb Z}_2$-graded parabosons in the multi-particle sector of a quantum model. The difference with respect to a system composed by ordinary bosons is spotted by measuring some selected observables on certain given eigenstates. The construction of the multi-particle states is made through the appropriate braided tensor product. The application of ${\mathbb Z}_2$- and ${\mathbb Z}_2\times {\mathbb Z}_2$- gradings produces $9$ inequivalent multi-particle Hilbert spaces of a $4\times 4$ matrix oscillator. The ${\mathbb Z}_2\times {\mathbb Z}_2$-graded parabosonic Hilbert space is one of them.
description: 21 pages
A HyperCard thesaurus : a new approach to computerised thesauri
Creators: name: Shamsuddin, Dahlia
Publisher: name: Loughborough University
Year: 2021
Subjects: subject: 89999 Information and Computing Sciences not elsewhere classified
subject: FOS: Computer and information sciences

description: A HyperCard thesaurus : a new approach to computerised thesauri
A hierarchy of multi-moment skyrmion phases in twisted magnetic bilayers
Creators: name: Ray, Sujay
name: Das, Tanmoy
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The recent discovery of two-dimensional (2D) Van der Waals (VdW) magnets is a crucial turning point in the quantum magnet research field, since quantum fluctuations and experimental difficulties often elude stable magnetic orders in 2D. This opens new doors to delve for novel quantum and topological spin configurations, which may or may not have direct analogs in bulk counterparts. Here we study a twisted bilayer geometry of 2D magnets in which long-range spin-spin interactions naturally commence along the inter-layer Heisenberg ($J_{\perp}$) and dipole-dipole ($J_{\rm D}$) channels. The $J_{\perp}-J_{\rm D}$ parameter space unveils a hierarchy of distinct skyrmions phases, ranging from point-, rod-, and ring-shaped topological charge distributions. Furthermore, we predict a novel topological antiferroelectric phase, where oppositely-charged antiskyrmion pairs are formed, and the corresponding topological dipole moments become ordered in a Néel-like state $-$ hence dubbed topological antiferroelectric state. The results indicate that twisted magnetic layer provides a new setting to engineer and tune a plethora of novel and exotic skyrmion phases and their dynamics.
description: 13 pages, 10 figures
Limits on Anomalous Triple Gauge Couplings in ppbar Collisions at sqrt{s}=1.96 TeV
Creators: name: CDF Collaboration
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We present a search for anomalous triple gauge couplings (ATGC) in WW and WZ boson production. The boson pairs are produced in ppbar collisions at sqrt{s}=1.96 TeV, and the data sample corresponds to 350 pb-1 of integrated luminosity collected with the CDF II detector at the Fermilab Tevatron. In this search one W decays to leptons, and the other boson (W or Z) decays hadronically. Combining with a previously published CDF measurement of Wgamma boson production yields ATGC limits of -0.18 < lambda < 0.17 and -0.46 < Delta kappa < 0.39 at the 95% confidence level, using a cut-off scale Lambda=1.5 TeV.
description: 7 pages, 3 figures. Submitted to Phys. Rev. D
Heterodyne detection enhanced by quantum correlation
Creators: name: Xie, Boya
name: Feng, Sheng
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Heterodyne detectors as phase-insensitive (PI) devices have found important applications in precision measurements such as space-based gravitational-wave (GW) observation. However, the output signal of a PI heterodyne detector is supposed to suffer from signal-to-noise ratio (SNR) degradation due to image band vacuum and imperfect quantum efficiency. Here we show that the SNR degradation can be overcome when the image band vacuum is quantum correlated with the input signal. We calculate the noise figure of the detector and prove the feasibility of heterodyne detection with enhanced noise performance through quantum correlation. This work should be of great interest to ongoing space-borne GW signal searching experiments.
description: 5 pages, 1 figure
VLBA determination of the distance to nearby star-forming regions I. The distance to T Tauri with 0.4% accuracy
Creators: name: Loinard, Laurent
name: Torres, Rosa M.
name: Mioduszewski, Amy J.
name: Rodriguez, Luis F.
name: Gonzalez-Lopezlira, Rosa A.
name: Lachaume, Regis
name: Vazquez, Virgilio
name: Gonzalez, Erandy
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: In this article, we present the results of a series of twelve 3.6-cm radio continuum observations of T Tau Sb, one of the companions of the famous young stellar object T Tauri. The data were collected roughly every two months between September 2003 and July 2005 with the Very Long Baseline Array (VLBA). Thanks to the remarkably accurate astrometry delivered by the VLBA, the absolute position of T Tau Sb could be measured with a precision typically better than about 100 micro-arcseconds at each of the twelve observed epochs. The trajectory of T Tau Sb on the plane of the sky could, therefore, be traced very precisely, and modeled as the superposition of the trigonometric parallax of the source and an accelerated proper motion. The best fit yields a distance to T Tau Sb of 147.6 +/- 0.6 pc. The observed positions of T Tau Sb are in good agreement with recent infrared measurements, but seem to favor a somewhat longer orbital period than that recently reported by Duchene et al. (2006) for the T Tau Sa/T Tau Sb system.
description: 24 pages, 3 pages, AASTEX format, accepted for publication in ApJ
TA'LIM JARAYONIDA IJTIMOIY TARMOQLARNING QOLLANILISHI: IJOBIY VA SALBIY TOMONLARI
Creators: name: Ernazarov, Alisher
name: Jolanov, Hasan
Publisher: name: Zenodo
Year: 2023

description: Ushbu maqola zamonaviy ta'lim jarayonida ijtimoiy tarmoqlarning ahamiyati va ta'lim imkoniyatlariga bag'ishlangan. Shuningdek, ijtimoiy tarmoqlardan ta'lim vositasi sifatida foydalanishning afzalliklari va kamchiliklari keltiriladi.
Development of the single nucleotide polymorphism markers for Phytophthora capsici resistance in Capsicum annuum
Creators: name: Namfon Chomkaeo
name: Darush Struss
name: Chotipa Sakulsingharoj
name: Varaporn Sangtong
name: Saengtong Pongjaroenkit
Publisher: name: Genetics Society of Thailand
Year: 2014
Subjects: single nucleotide polymorphism (SNP) markers, Capsicum annuum, Phytophthora resistance, quantitative trait loci (QTL), inheritance

description: 3, 7, Thai Journal of Genetics
Energy Performance of Buildings:
low energy heating and cooling in European climates
Creators: name: Ascione, Fabrizio
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2009

description: L’emanazione della Direttiva Europea 2002/91/CE (Energy Performance of Buildings Directive - EPBD) ha rivitalizzato e dato nuovo impulso alle tematiche proprie dell’efficienza energetica in edilizia, obbligando, in un contesto internazionale vivacizzato dalle problematiche ambientali e legate all’approvvigionamento energetico, gli Stati membri dell’Unione verso nuovi e comuni traguardi da raggiungere relativamente alla riduzione improrogabile della domanda di energia nel settore edilizio.
L’obiettivo dell’attività di ricerca riportata in questa Tesi è consistito nello studio di misure di efficienza energetica in diversi ambiti del settore civile, con particolare riferimento all’edilizia residenziale, al settore terziario ed alle architetture adibite a musei. Gli studi di efficienza energetica hanno valutato sia gli aspetti metodologici e procedurali alla luce dei nuovi orientamenti legislativi e normativi scaturiti dalla EPBD, sia le potenzialità di miglioramento delle prestazioni di involucri edilizi ed impianti, per quanto concerne gli usi energetici dovuti ai bisogni di riscaldamento, ventilazione e climatizzazione degli edifici.
Normalization of the Matter Power Spectrum via Higher-Order Angular Correlations of Luminous Red Galaxies
Creators: name: Ross, Ashley J.
name: Brunner, Robert J.
name: Myers, Adam D.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present a novel technique to measure $σ_8$, by measuring the dependence of the second-order bias of a density field on $σ_8$ using two separate techniques. Each technique employs area-averaged angular correlation functions ($\barω_N$), one relying on the shape of $\barω_2$, the other relying on the amplitude of $s_3$ ($s_3 =\barω_3/\barω_2^2$). We confirm the validity of the method by testing it on a mock catalog drawn from Millennium Simulation data and finding $σ_8^{measured}- σ_8^{true} = -0.002 \pm 0.062$. We create a catalog of photometrically selected LRGs from SDSS DR5 and separate it into three distinct data sets by photometric redshift, with median redshifts of 0.47, 0.53, and 0.61. Measurements of $c_2$, and $σ_8$ are made for each data set, assuming flat geometry and WMAP3 best-fit priors on $Ω_m$, $h$, and $Γ$. We find, with increasing redshfit, $c_2 = 0.09 \pm 0.04$, $0.09 \pm 0.05$, and $0.09 \pm 0.03$ and $σ_8 = 0.78 \pm 0.08$, $0.80 \pm 0.09$, and $0.80 \pm 0.09$. We combine these three consistent $σ_8$ measurements to produce the result $σ_8 = 0.79 \pm 0.05$. Allowing the parameters $Ω_m$, $h$, and $Γ$ to vary within their WMAP3 1$σ$ error, we find that the best-fit $σ_8$ does not change by more than 8% and we are thus confident our measurement is accurate to within 10%. We anticipate that future surveys, such as Pan-STARRS, DES, and LSST, will be able to employ this method to measure $σ_8$ to great precision, and will serve as an important check, complementary, on the values determined via more established methods.
description: 23 pages, 4 figures, preprint, accepted to ApJ
Expanding the momentum field of view in angle-resolved photoemission systems with hemispherical analyzers
Creators: name: Gauthier, Nicolas
name: Sobota, Jonathan A.
name: Pfau, Heike
name: Gauthier, Alexandre
name: Soifer, Hadas
name: Bachmann, Maja D.
name: Fisher, Ian R.
name: Shen, Zhi-Xun
name: Kirchmann, Patrick S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: In photoelectron spectroscopy, the measured electron momentum range is intrinsically related to the excitation photon energy. Low photon energies $<10$ eV are commonly encountered in laser-based photoemission and lead to a momentum range that is smaller than the Brillouin zones of most materials. This can become a limiting factor when studying condensed matter with laser-based photoemission. An additional restriction is introduced by widely used hemispherical analyzers that record only electrons photoemitted in a solid angle set by the aperture size at the analyzer entrance. Here, we present an upgrade to increase the effective solid angle that is measured with a hemispherical analyzer. We achieve this by accelerating the photoelectrons towards the analyzer with an electric field that is generated by a bias voltage on the sample. Our experimental geometry is comparable to a parallel plate capacitor and, therefore, we approximate the electric field to be uniform along the photoelectron trajectory. With this assumption, we developed an analytic, parameter-free model that relates the measured angles to the electron momenta in the solid and verify its validity by comparing with experimental results on the charge density wave material TbTe$_3$. By providing a larger field of view in momentum space, our approach using a bias potential considerably expands the flexibility of laser-based photoemission setups.
description: 11 pages, 7 figures
Air Fluorescence Relevant for Cosmic-Ray Detection - Summary of the 5th Fluorescence Workshop, El Escorial 2007
Creators: name: Arqueros, Fernando
name: Hoerandel, Joerg R.
name: Keilhauer, Bianca
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: High-energy cosmic rays with energies exceeding $10^{17}$ eV are frequently observed by measurements of the fluorescence light induced by air showers. A major contribution to the systematic uncertainties of the absolute energy scale of such experiments is the insufficient knowledge of the fluorescence light yield of electrons in air. The aim of the 5th Fluorescence Workshop was to bring together experimental and theoretical expertise to discuss the latest progress on the investigations of the fluorescence light yield. The results of the workshop will be reviewed as well as the present status of knowledge in this field. Emphasis is given to the fluorescence light yield important for air shower observations and its dependence on atmospheric parameters, like pressure, temperature, and humidity. The effects of the latest results on the light observed from air showers will be discussed.
description: Nucl. Instr. & Meth. in press
Dalitz plot analysis of the D+ to K-pi+pi+ decay in the FOCUS experiment
Creators: name: The FOCUS Collaboration
name: Link, J. M.
name: Pennington, M. R.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Using data collected by the high energy photoproduction experiment FOCUS at Fermilab we performed a Dalitz plot analysis of the Cabibbo favored decay D+ to K-pi+ pi+. This study uses 53653 Dalitz-plot events with a signal fraction of ~ 97%, and represents the highest statistics, most complete Dalitz plot analysis for this channel. Results are presented and discussed using two different formalisms. The first is a simple sum of Breit--Wigner functions with freely fitted masses and widths. It is the model traditionally adopted and serves as comparison with the already published analyses. The second uses a K-matrix approach for the dominant S-wave, in which the parameters are fixed by first fitting Kpi scattering data and continued to threshold by Chiral Perturbation Theory. We show that the Dalitz plot distribution for this decay is consistent with the assumption of two body dominance of the final state interactions and the description of these interactions is in agreement with other data on the Kpi final state.
description: 21 pages, 10 figures, to be submitted to Phys.Lett.B
Preparazione e caratterizzazione di sistemi epossidici con migliorate proprietà alla fiamma
Creators: name: De Fenzo, Anna
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2011

description: Il lavoro di dottorato ha riguardato lo studio di sistemi epossidici caricati con ritardanti di fiamma inorganici e analizzati mediante cono e micro calorimetro e analizzati termogravimetricamente per definire energie di attivazione dei vari step di degradzione. Inoltre lo stesso sistema epossidico è stato caricato con un materiale di origine naturale anche modificato chimicamente
Air taxi service for urban mobility: A critical review of recent developments, future challenges, and opportunities
Creators: name: Rajendran, Suchithra
name: Srinivas, Sharan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computers and Society (cs.CY)
subject: Optimization and Control (math.OC)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Expected to operate in the imminent future, air taxi service (ATS) is an aerial on-demand transport for a single passenger or a small group of riders, which seeks to transform the method of everyday commute. This uncharted territory in the emerging transportation world is anticipated to enable consumers bypass traffic congestion in urban road networks. By adopting an electric vertical takeoff and landing concept (eVTOL), air taxis could be operational from skyports retrofitted on building rooftops, thus gaining advantage from an implementation standpoint. Motivated by the potential impact of ATS, this study provides a review of air taxi systems and associated operations. We first discuss the current developments in the ATS (demand prediction, air taxi network design, and vehicle configuration). Next, we anticipate potential future challenges of ATS from an operations management perspective, and review the existing literature that could be leveraged to tackle these problems (ride-matching, pricing strategies, vehicle maintenance scheduling, and pilot training and recruitment). Finally, we detail future research opportunities in the air taxi domain.
description: This is a pre-print version of the manuscript accepted in Transportation Research Part E: Logistics and Transportation Review (https://doi.org/10.1016/j.tre.2020.102090)
Preparation and characterization of arbitrary states of four-dimensional qudits based on biphotons
Creators: name: Baek, So-Young
name: Straupe, Stanislav S.
name: Shurupov, Alexander P.
name: Kulik, Sergei P.
name: Kim, Yoon-Ho
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We report interferometric schemes to prepare arbitrary states of four-dimensional qudits (ququarts) based on biphoton states of ultrafast-pumped frequency-nondegenerate spontaneous parametric down-conversion. Preparation and tomographic characterization of a few examples of general single-ququart states, a pure state, a completely mixed state, and a partially-mixed state, are experimentally demonstrated.
Supersymmetrizing Landau Models
Creators: name: Ivanov, Evgeny
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: This is an overview of recent progress in constructing and studying superextensions of the Landau problem of a quantum particle on a plane in the uniform magnetic field, as well as of its Haldane's $S^2$ generalization ({\tt hep-th/0311159, hep-th/0404108, hep-th/0510019, hep-th/0612300}). The main attention is paid to the planar super Landau models which are invariant under the inhomogeneous supergroup ISU(1|1), a contraction of the supergroup SU(2|1), and provide minimal superextensions of the original Landau model. Their common notable feature is the presence of a hidden dynamical worldline N=2 supersymmetry. It exists at the classical and quantum levels and is revealed most naturally while passing to the new invariant inner products in the space of quantum states in order to make the norms of all states positive. For one of the planar models, the superplane Landau model, we present an off-shell worldline superfield formulation in which the N=2 supersymmetry gets manifest.
description: 16 pages, Talk at the International Workshop on Classical and Quantum Integrable Systems, BLTP, JINR, Dubna, January 22--25, 2007
Il controllo non ottimale del colesterolo LDL è un predittore indipendente di rimodellamento ventricolare sinistro postinfartuale
Creators: name: Di Marino, Serena
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2011

description: Il rimodellamento ventricolare sinistro indica un sovvertimento geometrico della cavità ventricolare indotto da cambiamenti di dimensioni, forma e funzione del ventricolo sinistro a seguito di un evento ischemico.I  pazienti al primo episodio infartuale che ricevono adeguata ed efficace terapia di riperfusione e trattati cronicamente con farmaci antirimodellamento, un insoddisfacente controllo dei valori del colesterolo LDL prima e dopo l'evento è un predittore indipendente di sviluppo di rimodellamento ventricolare
The Size Distributions of Asteroid Families in the SDSS Moving Object Catalog 4
Creators: name: Parker, Alex H.
name: Ivezic, Zeljko
name: Juric, Mario
name: Lupton, Robert H.
name: Sekora, Michael D.
name: Kowalski, Adam F.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Asteroid families, traditionally defined as clusters of objects in orbital parameter space, often have distinctive optical colors. We show that the separation of family members from background interlopers can be improved with the aid of SDSS colors as a qualifier for family membership. Based on an ~88,000 object subset of the Sloan Digital Sky Survey Moving Object Catalog 4 with available proper orbital elements, we define 37 statistically robust asteroid families with at least 100 members using a simple Gaussian distribution model in both orbital and color space. The interloper rejection rate based on colors is typically ~10% for a given orbital family definition, with four families that can be reliably isolated only with the aid of colors. About 50% of all objects in this data set belong to families, and this fraction varies from about 35% for objects brighter than an H magnitude of 13 and rises to 60% for objects fainter than this. The fraction of C-type objects in families decreases with increasing H magnitude for H > 13, while the fraction of S-type objects above this limit remains effectively constant. This suggests that S-type objects require a shorter timescale for equilibrating the background and family size distributions via collisional processing. The size distributions for 15 families display a well-defined change of slope and can be modeled as a "broken" double power-law. Such "broken" size distributions are twice as likely for S-type familes than for C-type families, and are dominated by dynamically old families. The remaining families with size distributions that can be modeled as a single power law are dominated by young families. When size distribution requires a double power-law model, the two slopes are correlated and are steeper for S-type families.
description: 50 pages, 16 figures, accepted for publication in Icarus
The AstroSat Mass Model: Imaging and Flux studies of off-axis sources with CZTI
Creators: name: Mate, Sujay
name: Chattopadhyay, Tanmoy
name: Bhalerao, Varun
name: Aarthy, E.
name: Balasubramanian, Arvind
name: Bhattacharya, Dipankar
name: Gupta, Soumya
name: Kutty, Krishnan
name: Mithun, N. P. S.
name: Palit, Sourav
name: Rao, A. R.
name: Saraogi, Divita
name: Vadawale, Santosh
name: Vibhute, Ajay
Publisher: name: arXiv
Year: 2021
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The Cadmium Zinc Telluride Imager (CZTI) on AstroSat is a hard X-ray coded-aperture mask instrument with a primary field of view of 4.6 x 4.6 degrees (FWHM). The instrument collimators become increasingly transparent at energies above $\sim$100 keV, making CZTI sensitive to radiation from the entire sky. While this has enabled CZTI to detect a large number of off-axis transient sources, calculating the source flux or spectrum requires knowledge of the direction and energy dependent attenuation of the radiation incident upon the detector. Here, we present a GEANT4-based mass model of CZTI and AstroSat that can be used to simulate the satellite response to the incident radiation, and to calculate an effective "response file" for converting the source counts into fluxes and spectra. We provide details of the geometry and interaction physics, and validate the model by comparing the simulations of imaging and flux studies with observations. Spectroscopic validation of the mass model is discussed in a companion paper, Chattopadhyay 2021.
description: Accepted in the "AstroSat - 5 years" special issue of the Journal of Astrophysics and Astronomy
Determinants of ICT Adoption Among Small Scale Agribusiness Enterprises In Somalia
Creators: name: Abdullahi, Husein Osman
name: Hassan, Abdikarim Abi
name: Mahmud, Murni
name: Ali, Abdifatah Farah
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computers and Society (cs.CY)
subject: FOS: Computer and information sciences

description: The use of Information and Communication Technology (ICT) can advance the Agricultural Business sector, particularly in a country seeking opportunities to explore the sector. There is evidence that ICT has made significant contributions to agribusiness because it allows enterprises to manage their operations, and it has major impacts on the business. However, the critical factors that motivate the adoption of new innovative technology by agribusiness enterprises are underexplored. The literature has indicated ICT adoption among small-scale agribusiness enterprises in Somalia is not fully understood. Nevertheless, this study addresses this gap by investigating the adoption of ICT among small-scale agribusiness enterprises in Somalia. The paper reports the use of the Technology, Organization, Environment (TOE) framework. An online survey has been conducted with random sampling for data collection, with 107 respondents. The respondents are from agribusiness staff and farmers from various agricultural companies in Somalia. After quantitative data analysis, the results indicated that relative advantage, complexity, top management support, and competitive pressure factors are significant contributors to ICT adoption in Somalian agribusiness enterprises, while ICT costs and vendor support are not significantly related to the adoption of ICT in agricultural business. This study concludes that ICT adoption in Somalia is inspired by insight and motivation rather than financial and external support. Understanding these factors leads to a better understanding of ICT adoption in Somalia. Additionally, it enriches the literature about the agriculture business on the African continent Keywords: Determinants, ICT Adoption, Agribusiness, Small Scale, TOE framework
description: 9 pages, 2 figures
Domain adaptation based self-correction model for COVID-19 infection segmentation in CT images
Creators: name: Jin, Qiangguo
name: Cui, Hui
name: Sun, Changming
name: Meng, Zhaopeng
name: Wei, Leyi
name: Su, Ran
Publisher: name: arXiv
Year: 2021
Subjects: subject: Image and Video Processing (eess.IV)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: The capability of generalization to unseen domains is crucial for deep learning models when considering real-world scenarios. However, current available medical image datasets, such as those for COVID-19 CT images, have large variations of infections and domain shift problems. To address this issue, we propose a prior knowledge driven domain adaptation and a dual-domain enhanced self-correction learning scheme. Based on the novel learning schemes, a domain adaptation based self-correction model (DASC-Net) is proposed for COVID-19 infection segmentation on CT images. DASC-Net consists of a novel attention and feature domain enhanced domain adaptation model (AFD-DA) to solve the domain shifts and a self-correction learning process to refine segmentation results. The innovations in AFD-DA include an image-level activation feature extractor with attention to lung abnormalities and a multi-level discrimination module for hierarchical feature domain alignment. The proposed self-correction learning process adaptively aggregates the learned model and corresponding pseudo labels for the propagation of aligned source and target domain information to alleviate the overfitting to noises caused by pseudo labels. Extensive experiments over three publicly available COVID-19 CT datasets demonstrate that DASC-Net consistently outperforms state-of-the-art segmentation, domain shift, and coronavirus infection segmentation methods. Ablation analysis further shows the effectiveness of the major components in our model. The DASC-Net enriches the theory of domain adaptation and self-correction learning in medical imaging and can be generalized to multi-site COVID-19 infection segmentation on CT images for clinical deployment.
Periodic quotients of hyperbolic and large groups
Creators: name: Minasyan, A.
name: Olshanskii, A. Yu.
name: Sonkin, D.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: 20F50, 20F67

description: Let $G$ be either a non-elementary (word) hyperbolic group or a large group (both in the sense of Gromov). In this paper we describe several approaches for constructing continuous families of periodic quotients of $G$ with various properties. The first three methods work for any non-elementary hyperbolic group, producing three different continua of periodic quotients of $G$. They are based on the results and techniques, that were developed by Ivanov and Olshanskii in order to show that there exists an integer $n$ such that $G/G^n$ is an infinite group of exponent $n$. The fourth approach starts with a large group $G$ and produces a continuum of pairwise non-isomorphic periodic residually finite quotients. Speaking of a particular application, we use each of these methods to give a positive answer to a question of Wiegold from Kourovka Notebook.
description: Version 3: 26 pages; several misprints were corrected
Transient dynamics of a magnetic impurity coupled to superconducting electrodes: exact numerics versus perturbation theory
Creators: name: Souto, R. Seoane
name: Feiguin, A. E.
name: Martín-Rodero, A.
name: Yeyati, A. Levy
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Impurities coupled to superconductors offer a controlled platform to understand the interplay between superconductivity, many-body interactions, and non-equilibrium physics. In the equilibrium situation, local interactions at the impurity induce a transition between the spin-singlet to the spin-doublet ground state, resulting in a supercurrent sign reversal ($0-π$ transition). In this work, we apply the exact time-dependent density matrix renormalization group method to simulate the transient dynamics of such superconducting systems. We also use a perturbative approximation to analyze their properties at longer times. These two methods agree for a wide range of parameters. In a phase-biased situation, the system gets trapped in a metastable state characterized by a lower supercurrent compared to the equilibrium case. We show that local Coulomb interactions do not provide an effective relaxation mechanism for the initially trapped quasiparticles. In contrast, other relaxation mechanisms, such as coupling to a third normal lead, make the impurity spin relax for parameter values corresponding to the equilibrium $0$ phase. For parameters corresponding to the equilibrium $π$ phase the impurity converges to a spin-polarized stationary state. Similar qualitative behavior is found for a voltage-biased junction, which provides an effective relaxation mechanism for the trapped quasiparticles in the junction.
description: 13 pages, 12 figures
Il problema dell'illuminazione globale per il rendering e sua soluzione in ambiente GPU
Creators: name: Romano, Diego
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2011

description: In questo lavoro è stato preso in esame il problema dell'illuminazione globale nell'ambito della grafica computazionale, con l'obiettivo di sviluppare un software che sfrutti la potenza di calcolo delle GPU.

Trattandosi della generazione di immagini sintetiche rappresentanti una scena artificiale, utilizzando il procedimento detto di rendering, sono stati descritti i passi necessari: dalla creazione di un modello descrittivo della scena, fino alla visualizzazione dell'immagine nei termini di una matrice di pixel.

Concentrando l'attenzione sulla fase di rendering, è stato descritto il modello matematico sottostante i fenomeni di propagazione della luce in un ambiente. Tra le formulazioni presenti in letteratura, è stata preferita quella legata alla radianza luminosa, che appare essere la più versatile per descrivere una maggiore varietà di fenomeni ottici in un'ampia gamma di scene.

Al fine di individuare un opportuno metodo adatto all'implementazione efficiente su GPU, sono stati studiati gli approcci più diffusi, evidenziando le relative approssimazioni, e le loro limitazioni in termini qualitativi dei risultati. È stato poi introdotto un nuovo metodo iterativo di cui si è provata la convergenza.

Passando poi allo studio dell'implementazione sulle GPU, è stata introdotta l'architettura parallela con le caratteristiche più rilevanti per la valutazione del software che si vuole sviluppare. Sono poi stati analizzati i vari metodi risolutivi alla luce di nuovi parametri di valutazione delle prestazioni e delle aspettative qualitative. Quindi è stato implementato un algoritmo ibrido sia in versione sequenziale, sia in versione parallela multithreading.

Infine sono stati analizzati i risultati dell'implementazione dal punto di vista della qualità delle immagini ottenute, e delle prestazioni raggiunte con l'utilizzo delle GPU.
Dynamics of the molecular orientation field coupled to ions in two-dimensional ferroelectric liquid crystals
Creators: name: Pelcovits, Robert A.
name: Lee, J. -B.
name: Meyer, R. B.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Molecular orientation fluctuations in ferroelectric smectic liquid crystals produce space charges, due to the divergence of the spontaneous polarization. These space charges interact with mobile ions, so that one must consider the coupled dynamics of the orientation and ionic degrees of freedom. Previous theory and light scattering experiments on thin free-standing films of ferroelectric liquid crystals have not included this coupling, possibly invalidating their quantitative conclusions. We consider the most important case of very slow ionic dynamics, compared to rapid orientational fluctuations, and focus on the use of a short electric field pulse to quench orientational fluctuations. We find that the resulting change in scattered light intensity must include a term due to the quasistatic ionic configuration, which has previously been ignored. In addition to developing the general theory, we present a simple model to demonstrate the role of this added term.
RUOLO DELLA TAC-PET NELLA DIAGNOSI DEI TUMORI MALIGNI MULTIPLI PRIMITIVI
Creators: name: Tedesco, Gioacchino
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2011

description: I tumori multipli primitivi rappresentano tumori insorti in un singolo paziente che presentano determinate caratteristiche cliniche ed istologiche. Si tratta di tumori chiaramente maligni dal punto di vista istopatologico; geograficamente distinti e non connessi da alterazioni sottomucose o intraepiteliali (concetto attuale di skip metastasis); con esclusa la possibilità che il secondo tumore sia una metastasi del primo.
Using collimated CZTI as all sky X-ray detector based on Earth Occultation Technique
Creators: name: Singhal, Akshat
name: Srinivasan, Rahul
name: Bhalerao, Varun
name: Bhattacharya, Dipankar
name: Rao, A. R.
name: Vadawale, Santosh
Publisher: name: arXiv
Year: 2021
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: All-sky monitors can measure the fluxes of astrophysical sources by measuring the changes in observed counts as the source is occulted by the Earth. Such measurements have typically been carried out by all-sky monitors like $\textit{CGRO}$-BATSE and $\textit{Fermi}$-GBM. We demonstrate for the first time the application of this technique to measure fluxes of sources using a collimated instrument: the Cadmium Zinc Telluride detector on $\textit{AstroSat}$. Reliable flux measurements are obtained for the Crab nebula and pulsar, and for Cyg X-1 by carefully selecting the best occultation data sets. We demonstrate that CZTI can obtain such measurements for hard sources with intensities $\gtrsim1$Crab.
description: Accepted in the "AstroSat - 5 years" special issue of the Journal of Astrophysics and Astronomy
Single-valley high-mobility (110) AlAs quantum wells with anisotropic mass
Creators: name: Dasgupta, S.
name: Birner, S.
name: Knaak, C.
name: Bichler, M.
name: Morral, A. Fontcuberta i
name: Abstreiter, G.
name: Grayson, M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We studied a doping series of (110)-oriented AlAs quantum wells (QWs) and observed transport evidence of single anisotropic-mass valley occupancy for the electrons in a 150 Åwide QW. Our calculations of strain and quantum confinement for these samples predict single anisotropic-mass valley occupancy for well widths $W$ greater than 53 Å. Below this, double-valley occupation is predicted such that the longitudinal mass axes are collinear. We observed mobility anisotropy in the electronic transport along the crystallographic directions in the ratio of 2.8, attributed to the mass anisotropy as well as anisotropic scattering of the electrons in the X-valley of AlAs.
The biotransformation of Bupleuri Radix by human gut microbiota
Creators: name: Tang, Cui
name: Fu, Qiachi
name: Chen, Xia
name: Hu, Yang
name: Renaud, Helen
name: Ma, Chong
name: Rao, Tai
name: Chen, Yao
name: Tan, Zhirong
name: Klaassen, Curtis D.
name: Shi, Shuyun
name: Guo, Ying
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Biochemistry
subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Pharmacology
subject: Environmental Sciences not elsewhere classified
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: Sociology
subject: FOS: Sociology
subject: Biological Sciences not elsewhere classified
subject: Cancer

description: 1. Bupleuri Radix (BR) is a herbal medicine traditionally used orally in oriental countries, which inevitably comes into contact with the intestinal microbiota. However, whether gut microbiota contribute to the biotransformation of BR, and/or the formation of pharmacologically active compounds remains unknown. 2. In this study, the main saikosaponins (SAPs) of Bupleurum (including saikosaponin a, b1, b2, c, d, f, h) and BR extract (BRE) were individually incubated with human fecal suspensions (HFS), and metabolic time courses of SAPs and their metabolites by human gut bacteria were systematically characterized. 3. Deglycosylation and dehydration were the main metabolic pathways identified for SAPs including newly investigated saikosaponin f (SSf) and saikosaponin h (SSh); dehydration had not been reported previously. A total of 19 dehydrated and deglycosylated metabolites of SAPs were detected and characterized, and 10 of them were newly identified. Moreover, SAPs of BRE were found to be deglycosylated to prosaikogenins. In addition, 13 metabolic pathways related to human gut microbiota were identified for phytochemicals of BRE except for SAPs. Gut microbiota may play a significant role in the biotransformation of BR in humans.
Polymer-induced tubulation in lipid vesicles
Creators: name: Campelo, F.
name: Hernandez-Machado, A.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Subcellular Processes (q-bio.SC)
subject: Soft Condensed Matter (cond-mat.soft)
subject: Quantitative Methods (q-bio.QM)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: A mechanism of extraction of tubular membranes from a lipid vesicle is presented. A concentration gradient of anchoring amphiphilic polymers generates tubes from bud-like vesicle protrusions. We explain this mechanism in the framework of the Canham-Helfrich model. The energy profile is analytically calculated and a tube with a fixed length, corresponding to an energy minimum, is obtained in a certain regime of parameters. Further, using a phase-field model, we corroborate these results numerically. We obtain the growth of tubes when a polymer source is added, and the bud-like shape after removal of the polymer source, in accordance with recent experimental results.
Veterinary public health aspects of hazards occurring along
the pig production line
Creators: name: Sarno, Eleonora
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2013

description: Healthy food producing animals were recognized in recent years as important carriers of bacterial and viral pathogens causing human illness.
To obtain microbiological data from Swiss pig at slaughter, tonsil samples were examined in the present work for the occurrence of Erysipelothrix spp., Salmonella spp., and Listeria spp. No Erysipelothrix spp. were detected in 250 tonsil samples by culture method. Salmonella spp. were detected (ISO 6579:09.2006) in only 2 out of 250 (0.8 %) samples. The two isolates were identified as Salmonella Bredeney and Salmonella Kedougou, which are only rarely reported as cause of human illness. Listeria spp. were detected (ISO 11290-1:2004) in 14 out of 250 (5.6 %) samples. Of the 14 isolates, nine were identified as Listeria monocytogenes (belonging to serotypes 1/2a, 1/2 b, and 4b), four as Listeria ivanovii, and one as Listeria innocua. Though numbers were low compared to the data from some other European countries, the present study shows that Salmonella  and L. monocytogenes  could be detected in the tonsils of healthy animals and these pathogens might pose a threat for the contamination of carcasses and slaughter environment.
To determine the seroprevalence of anti-hepatitis E virus (HEV) Ig G and anti-Salmonella antibodies, meat juice samples (diaphragm muscle) from healthy fattening pigs at slaughter were collected. Based on pooled samples 120 out of 200 (60 %) and 8 out of 200 (4 %) samples tested positive for anti-HEV Ig G and anti-Salmonella antibodies, respectively. HEV seems to be highly prevalent among fattening pigs in Switzerland, whereas the low seroprevalence of anti-Salmonella antibodies has not changed in recent years.
To investigate the seroprevalence of anti-HEV Ig G in healthy slaughtered sows, serum samples collected between 1988-1991 were analyzed. Based on the stored samples, 234 out of 240 (97.5 %) tested positive. Although HEV has become of interest in view of public health aspects including foodborne transmission only recently, our findings clearly indicate that HEV is circulating in the Swiss pig population already for many years.
To screen for the occurrence of carbapenemase-producing Enterobacteriaceae (CPE), fecal samples were collected from 200 fattening pigs at slaughter. No evidence  for the occurrence of CPE in food-producing animals needs currently to be postulated in Switzerland.
Wegner bounds for a two-particle tight binding model
Creators: name: Chulaevsky, Victor
name: Suhov, Yuri M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We consider a quantum two-particle system on a d-dimensional lattice with interaction and in presence of an IID external potential. We establish Wegner-typer estimates for such a model. The main tool used is Stollmann's lemma.
Multiobjective evolutionary-based optimization methods for trajectory planning of a quadrotor UAV
Creators: name: D'Amato, Egidio
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2012

description: This thesis describes the main research activity developed in a three years PhD program on flight dynamics. Optimization and UAVs flight control have been the main focus with methodological contributions on optimization, numerical and experimental work.
Unmanned Aerial Vehicles (UAV) captured the attention of both research and industrial worlds as a replacement for expensive human-piloted vehicles. In the last decade, they became widely used for several applications in which humans could be unnecessary or in some cases too in danger.
Many laboratories in the area of flight control, but also in the areas of robotics and control engineering in general, made significant research experiences on quadrotors.
A collaboration between University of Naples "Parthenope" and the Second University of Naples is aimed at designing and using UAVs for educational and research purposes. More than one quadrotor was built, tested in flight and used as a platform for testing flight control and navigation systems.
Several optimization problems may be encountered in the design of an UAV.
During the design phase, they arise from the choice of the hardware, the design and layout of the structure, the aerodynamics. On the other hand, for the Guidance Navigation and Control system, the management of single or fleets of UAVs requires the solution of many non-linear optimization problems. For this reason a multi-objective general purpose optimization software has been developed, integrating evolutionary methods, as genetic algorithm and ant colony, with game theory paradigms, as Nash and Stackelberg equilibria.
These methods have been primarily used to solve trajectory optimization problems with the scope of searching efficient flight trajectories in the presence of constraints.
The thesis is developed around the flight control of a quadrotor UAV. The following are the main steps of the work described in this thesis:
- dynamic and aerodynamic modelling oriented to flight control design;
- development of a distributed general purpose optimization software implementing Game Theory based paradigms and Ant Colony algorithm hybridization;
- Application of the above optimization methods to trajectory planning;
- Numerical simulations and flight experiments.
In Chapter 2, the quadrotor platform is described, together with the mathematical modelling and the design of the low level flight control system (attitude and speed control). In Chapter 3 the structure of the general purpose optimization software, mainly focused on the game theory layer and the ant colony algorithm is presented. In Chapter 4 the objectives of the optimization software are described and solved. Finally, in the Chapter 5, numerical simulations and flight tests are are shown.
Chaos and complexity in astrophysics
Creators: name: Regev, Oded
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Methods and techniques of the theory of nonlinear dynamical systems and patterns can be useful in astrophysical applications. Some works on the subjects of dynamical astronomy, stellar pulsation and variability, as well as spatial complexity in extended systems, in which such approaches have already been utilized, are reviewed. Prospects for future directions in applications of this kind are outlined.
description: to appear in the Springer "Encyclopedia of Complexity and System Science". The full text is at http://physics.technion.ac.il/~regev/ccastro.pdf