cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Room-temperature single-photon source with near-millisecond built-in memory
Creators: name: Dideriksen, Karsten B.
name: Schmieg, Rebecca
name: Zugenmaier, Michael
name: Polzik, Eugene S.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Non-classical photon sources are a crucial resource for distributed quantum networks. Photons generated from matter systems with memory capability are particularly promising, as they can be integrated into a network where each source is used on-demand. Among all kinds of solid state and atomic quantum memories, room-temperature atomic vapours are especially attractive due to their robustness and potential scalability. To-date room-temperature photon sources have been limited either in their memory time or the purity of the photonic state. Here we demonstrate a single-photon source based on room-temperature memory. Following heralded loading of the memory, a single photon is retrieved from it after a variable storage time. The single-photon character of the retrieved field is validated by the strong suppression of the two-photon component with antibunching as low as $g^{(2)}_{\text{RR|W=1}} = 0.20 \pm 0.07$. Non-classical correlations between the heralding and the retrieved photons are maintained for up to $τ_{\text{NC}}^{\mathcal R} = (0.68\pm 0.08)$ ms, more than two orders of magnitude longer than previously demonstrated with other room-temperature systems. Correlations sufficient for violating Bell inequalities exist for up to $τ_{\text{BI}} = (0.15 \pm 0.03)$ ms.
description: 7 pages, 4 figures main text plus 6 pages, 5 figures supplement
A circuit analysis of habituation in Caenorhabditis elegans
Creators: name: Wicks, Stephen Robert
Publisher: name: University of British Columbia
Year: 2009

description: The tap withdrawal response of the nematode Caenorhabditis elegans supports several forms of behavioural plasticity, including habituation (Rankin, Beck, & Chiba, 1990). The relative simplicity of this organism, both in terms of its nervous system and its genetic tractability, suggest that it would be a fruitful model system within which to investigate the neural and molecular substrates of learning. This report examines the production of the tap withdrawal response and the plasticity exhibited by that response at the cellular/circuit level. The neural circuit that mediates the tap response was identified through a program of single-cell laser microsurgery. Further behavioural analyses determined some of the functional properties of the tap withdrawal circuit neurons, both in the production of the tap withdrawal response and in the generation of the plasticity that that response expresses. First, this work demonstrated that the response was not unitary, but rather was composed of two competing reflexive behaviours: forward locomotion in response to posterior mechanosensory input and backward locomotion in response to anterior mechanosensory input. An animal's response to given stimulus was determined by the relative degree to which each of these reflexes were recruited. Second, it was demonstrated that each constituent reflex habituated in the absence of the other, and that habituation of the intact response was a summation of these two processes. Third, a dynamic network simulation of the circuit was used to predict the sign or polarity of the synapses that constitute the circuit. Fourth, it was demonstrated that at least two independent interstimulus interval-dependent processes were recruited during habituation: One that affects habituation kinetics and one that affects recovery from habituation. Finally, an analysis of the effects of tap withdrawal response habituation on other non-mechanosensory withdrawal behaviours was used, in conjunction with ablation studies, to identify potential loci of change within the circuit that might underlie habituation. The implications both of the functional properties of tap withdrawal circuit elements during habituation and the restriction of potential sites of change are discussed.
Effect of controlled point-like disorder induced by 2.5 MeV electron irradiation on nematic resistivity anisotropy of hole-doped (Ba,K)Fe$_2$As$_2$
Creators: name: Tanatar, M. A.
name: Timmons, Erik I.
name: Ko'nczykowski, M.
name: Cavani, O.
name: Cho, Kyuil
name: Liu, Yong
name: Lograsso, T. A.
name: Prozorov, R.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: In-plane anisotropy of electrical resistivity was studied in samples of the hole-doped Ba$_{1-x}$K$_x$Fe$_2$As$_2$ in the composition range $0.21 \leq x \leq 0.26$ where anisotropy changes sign. Low-temperature ($\sim$20~K) irradiation with relativistic 2.5 MeV electrons was used to control the level of disorder and residual resistivity of the samples. Modification of the stress-detwinning technique enabled measurements of the same samples before and after irradiation, leading to conclusion of anisotropic character of predominantly inelastic scattering processes. Our main finding is that the resistivity anisotropy is of the same sign irrespective of residual resistivity, and remains the same in the orthorhombic $C_2$ phase above the re-entrant tetragonal transition. Unusual $T$-linear dependence of the anisotropy $Δρ\equiv ρ_a(T)-ρ_b(T)$ is found in pristine samples with $x=$0.213 and $x=$0.219, without similar signatures in either $ρ_a(T)$ or $ρ_b(T)$. We show that this feature can be reproduced by a phenomenological model of R.~M.~Fernandes {\it et al.} Phys. Rev. Lett. {\bf 107},217002 (2011). We speculate that onset of fluctuations of nematic order on approaching the instability towards the re-entrant tetragonal phase contributes to this unusual dependence.
Can a galaxy redshift survey measure dark energy clustering?
Creators: name: Takada, Masahiro
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: (abridged) A wide-field galaxy redshift survey allows one to probe galaxy clustering at largest spatial scales, which carries an invaluable information on horizon-scale physics complementarily to the cosmic microwave background (CMB). Assuming the planned survey consisting of z~1 and z~3 surveys with areas of 2000 and 300 square degrees, respectively, we study the prospects for probing dark energy clustering from the measured galaxy power spectrum, assuming the dynamical properties of dark energy are specified in terms of the equation of state and the effective sound speed c_e in the context of an adiabatic cold dark matter dominated model. The dark energy clustering adds a power to the galaxy power spectrum amplitude at spatial scales greater than the sound horizon, and the enhancement is sensitive to redshift evolution of the net dark energy density, i.e. the equation of state. We find that the galaxy survey, when combined with Planck, can distinguish dark energy clustering from a smooth dark energy model such as the quintessence model (c_e=1), when c_e<0.04 (0.02) in the case of the constant equation of state w_0=-0.9 (-0.95). An ultimate full-sky survey of z~1 galaxies allows the detection when c_e<0.08 (0.04) for w_0=0.9 (-0.95). We also investigate a degeneracy between the dark energy clustering and the non-relativistic neutrinos implied from the neutrino oscillation experiments, because the two effects both induce a scale-dependent modification in the galaxy power spectrum shape at largest spatial scales accessible from the galaxy survey. It is shown that a wider redshift coverage can efficiently separate the two effects by utilizing the different redshift dependences, where dark energy clustering is apparent only at low redshifts z<1.
description: 14 pages, 7 figures; minor changes to match the published version
On sound source localization of speech signals using deep neural networks
Creators: name: Roden, Reinhild
name: Moritz, Niko
name: Gerlach, Stephan
name: Weinzierl, Stefan
name: Goetze, Stefan
Publisher: name: Technische Universität Berlin
Year: 2015
Subjects: subject: 534 Schall und verwandte Schwingungen
subject: 620 Ingenieurwissenschaften und zugeordnete Tätigkeiten
subject: speech
subject: deep neural network
subject: DNN
subject: interaural level di erence
subject: ILD
subject: interaural phase difference
subject: IPD
subject: interaural time delay
subject: ITD

description: In recent years artificial neural networks are successfully applied especially in the context of automatic speech recognition. As information processing systems, neural networks are trained by, e.g., backpropagation or restricted Boltzmann machines to classify patterns at the input of the system. The current work presents the implementation of a deep neural network (DNN) architecture for acoustic source localization.
Quantum algorithms with local particle number conservation: noise effects and error correction
Creators: name: Streif, Michael
name: Leib, Martin
name: Wudarski, Filip
name: Rieffel, Eleanor
name: Wang, Zhihui
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Quantum circuits with local particle number conservation (LPNC) restrict the quantum computation to a subspace of the Hilbert space of the qubit register. In a noiseless or fault-tolerant quantum computation, such quantities are preserved. In the presence of noise, however, the evolution's symmetry could be broken and non-valid states could be sampled at the end of the computation. On the other hand, the restriction to a subspace in the ideal case suggest the possibility of more resource efficient error mitigation techniques for circuits preserving symmetries that are not possible for general circuits. Here, we analyze the probability of staying in such symmetry-preserved subspaces under noise, providing an exact formula for local depolarizing noise. We apply our findings to benchmark, under depolarizing noise, the symmetry robustness of XY-QAOA, which has local particle number conserving symmetries, and is a special case of the Quantum Alternating Operator Ansatz. We also analyze the influence of the choice of encoding the problem on the symmetry robustness of the algorithm and discuss a simple adaption of the bit flip code to correct for symmetry-breaking errors with reduced resources.
Uniqueness of excited states to $-Δu+u-u^3=0$ in three dimensions
Creators: name: Cohen, Alex
name: Li, Zhenhao
name: Schlag, Wilhelm
Publisher: name: arXiv
Year: 2021
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35J60, 35B05

description: We prove the uniqueness of several excited states to the ODE $\ddot y(t) + \frac{2}{t} \dot y(t) + f(y(t)) = 0$, $y(0) = b$, and $\dot y(0) = 0$ for the model nonlinearity $f(y) = y^3 - y$. The $n$-th excited state is a solution with exactly $n$ zeros and which tends to $0$ as $t \to \infty$. These represent all smooth radial nonzero solutions to the PDE $Δu + f(u)= 0$ in $H^1$. We interpret the ODE as a damped oscillator governed by a double-well potential, and the result is proved via rigorous numerical analysis of the energy and variation of the solutions. More specifically, the problem of uniqueness can be formulated entirely in terms of inequalities on the solutions and their variation, and these inequalities can be verified numerically.
description: 19 pages, 5 figures. Published in Analysis & PDE
Morphology of anisotropic chains in a magneto-rheological fluid during aggregation and disaggregation processes
Creators: name: Domínguez-García, P.
name: Melle, Sonia
name: Rubio, M. A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We study the morphology of the chain-like aggregates formed when a external constant and uniaxial magnetic field is applied to a magneto-rheological (MR) fluid. In order to characterize the conformation of the aggregates, we study the evolution of various fractal dimensions during aggregation and disaggregation processes (i.e., when the applied field is switched on and off), using video-microscopy and image analysis. Experiments have been performed by varying the values of two external parameters: the magnetic field amplitude and particle concentration. We found that the box-counting dimension, related with how the aggregates occupy the surrounding space, depends on the ratio $R_1/R_0$. During the first stage of the disaggregation process, when the particles are moving by Brownian motion inside the aggregate, Family-Vicsek scaling function is verified.
description: Fig. 11 can not be included for a issue in the compilation. See pub. article
Order parameter conditions from mutual information and symmetry conditions
Creators: name: Arraut, Ivan
name: Yu, Wing Chi
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The mutual information method has demonstrated to be very useful for deriving the potential order parameter of a system. Although the method suggests some constraints which help to define this quantity, there is still some freedom in the definition. The method then results inefficient for cases where we have order parameters with a large number of constants in the expansion, which happens when we have many degenerate vacuums. Here we introduce some additional constraints based on the existence of broken symmetries, which help us to reduce the arbitrariness in the definitions of the order parameter in the proposed mutual information method.
description: 9 pages, 1 figure
Verification of joint measurability using phase-space quasiprobability distributions
Creators: name: Rahimi-Keshari, Saleh
name: Mehboudi, Mohammad
name: De Santis, Dario
name: Cavalcanti, Daniel
name: Acín, Antonio
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Measurement incompatibility is a distinguishing property of quantum physics and an essential resource for many quantum information processing tasks. We introduce an approach to verify the joint measurability of measurements based on phase-space quasiprobability distributions. Our results therefore establish a connection between two notions of non-classicality, namely the negativity of quasiprobability distributions and measurement incompatibility. We show how our approach can be applied to the study of incompatibility-breaking channels and derive incompatibility-breaking sufficient conditions for bosonic systems and Gaussian channels. In particular, these conditions provide useful tools for investigating the effects of errors and imperfections on the incompatibility of measurements in practice. To illustrate our method, we consider all classes of single-mode Gaussian channels. We show that pure lossy channels with 50% or more losses break the incompatibility of all measurements that can be represented by non-negative Wigner functions, which includes the set of Gaussian measurements.
description: 9 pages, 1 figure, 1 table
Asymptotic scaling symmetries for nonlinear PDEs
Creators: name: Gaeta, G.
name: Mancinelli, R.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: In some cases, solutions to nonlinear PDEs happen to be asymptotically (for large $x$ and/or $t$) invariant under a group $G$ which is not a symmetry of the equation. After recalling the geometrical meaning of symmetries of differential equations -- and solution-preserving maps -- we provide a precise definition of asymptotic symmetries of PDEs; we deal in particular, for ease of discussion and physical relevance, with scaling and translation symmetries of scalar equations. We apply the general discussion to a class of ``Richardson-like'' anomalous diffusion and reaction-diffusion equations, whose solution are known by numerical experiments to be asymptotically scale invariant; we obtain an analytical explanation of the numerically observed asymptotic scaling properties. We also apply our method to a different class of anomalous diffusion equations, relevant in optical lattices. The methods developed here can be applied to more general equations, as clear by their geometrical construction.
Artificial Intelligence Technologies in Education: Benefits, Challenges and Strategies of Implementation
Creators: name: Owoc, Mieczysław L.
name: Sawicka, Agnieszka
name: Weichbroth, Paweł
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computers and Society (cs.CY)
subject: FOS: Computer and information sciences

description: Since the education sector is associated with highly dynamic business environments which are controlled and maintained by information systems, recent technological advancements and the increasing pace of adopting artificial intelligence (AI) technologies constitute a need to identify and analyze the issues regarding their implementation in education sector. However, a study of the contemporary literature reveled that relatively little research has been undertaken in this area. To fill this void, we have identified the benefits and challenges of implementing artificial intelligence in the education sector, preceded by a short discussion on the concepts of AI and its evolution over time. Moreover, we have also reviewed modern AI technologies for learners and educators, currently available on the software market, evaluating their usefulness. Last but not least, we have developed a strategy implementation model, described by a five-stage, generic process, along with the corresponding configuration guide. To verify and validate their design, we separately developed three implementation strategies for three different higher education organizations. We believe that the obtained results will contribute to better understanding the specificities of AI systems, services and tools, and afterwards pave a smooth way in their implementation.
Profilometry and stress analysis of suspended nanostructured thin films
Creators: name: Darki, Ali Akbar
name: Parthenopoulos, Alexios
name: Nygaard, Jens Vinge
name: Dantan, Aurélien
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The profile of suspended silicon nitride thin films patterned with one-dimensional subwavelength grating structures is investigated using Atomic Force Microscopy. We first show that the results of the profilometry can be used as input to Rigorous Coupled Wave Analysis simulations to predict the transmission spectrum of the gratings under illumination by monochromatic light at normal incidence and compare the results of the simulations with experiments. Secondly, we observe sharp vertical deflections of the films at the boundaries of the patterned area due to local modifications of the tensile stress during the patterning process. These deflections are experimentally observed for various grating structures and investigated on the basis of a simple analytical model as well as finite element method simulations.
Dinner conversation
Creators: name: Intanai, Thongwilai
name: Sridachart, Khamsroy
name: Thawichart, Somphong
name: Lau-Preechathammarach, Raksit Tyler
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2023
Subjects: subject: kdt

description: Conversation over dinner at KhsSc's house. Recorder: Zoom H4n. Microphone: internal.
FedMood: Federated Learning on Mobile Health Data for Mood Detection
Creators: name: Xu, Xiaohang
name: Peng, Hao
name: Sun, Lichao
name: Bhuiyan, Md Zakirul Alam
name: Liu, Lianzhong
name: He, Lifang
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computers and Society (cs.CY)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Depression is one of the most common mental illness problems, and the symptoms shown by patients are not consistent, making it difficult to diagnose in the process of clinical practice and pathological research. Although researchers hope that artificial intelligence can contribute to the diagnosis and treatment of depression, the traditional centralized machine learning needs to aggregate patient data, and the data privacy of patients with mental illness needs to be strictly confidential, which hinders machine learning algorithms clinical application. To solve the problem of privacy of the medical history of patients with depression, we implement federated learning to analyze and diagnose depression. First, we propose a general multi-view federated learning framework using multi-source data, which can extend any traditional machine learning model to support federated learning across different institutions or parties. Secondly, we adopt late fusion methods to solve the problem of inconsistent time series of multi-view data. Finally, we compare the federated framework with other cooperative learning frameworks in performance and discuss the related results.
Cominuscule tableau combinatorics
Creators: name: Thomas, Hugh
name: Yong, Alexander
Publisher: name: arXiv
Year: 2007
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: We study "cominuscule tableau combinatorics" by generalizing constructions of M. Haiman, S. Fomin and M.-P. Schützenberger. In particular, we extend the dual equivalence ideas of [Haiman, 1992] to reformulate the generalized Littlewood-Richardson rule for cominuscule G/P Schubert calculus from [Thomas-Yong, 2006]. We apply dual equivalence to give an alternative and independent proof of the jeu de taquin results of [Proctor, 2004] needed in our earlier work. We also extend Fomin's growth diagram description of jeu de taquin; the inherent symmetry of these diagrams leads to a generalization of Schützenberger's evacuation involution. Finally, these results are applied to give an cominuscule extension of the carton rule of [Thomas-Yong, 2008].
description: 16 pages; to appear in the MSJ-SI 2012 Proceedings of the "International summer school and conference on Schubert calculus"
Genetic and molucular analyses of the role of the Unusual Floral Organs gene in regulation of shoot and organ identity in Arabidopsis Thaliana
Creators: name: Wilkinson, Mark
Publisher: name: University of British Columbia
Year: 2009

description: Shortly after initiation, shoot and floral organ primordia become determined to particular fates based on their spatial/temporal position in the plant. Many genes are known which affect the proper regulation of this process, and these genes are expressed in spatial/temporal patterns consistent with the developmental decisions they regulate. Little is known about the mechanisms by which these regulatory genes achieve their final patterns in the developing plant. I have identified a novel gene involved in regulation of flower initiation and development in Arabidopsis. This gene is designated UNUSUAL FLORAL ORGANS (UFO). Ufo plants generate more coflorescences than do the wild type and, unlike wild type, coflorescences often appear apical to the first floral shoot, indicating that UFO has a role in regulating coflorescence versus floral fate determination by lateral shoots. In addition, Ufo floral organs exhibit variable homeotic transformations to any of the four organ types in the second, and third whorls, suggesting that ufo mutations result in variable expression levels and/or patterns of the organ identity genes. These hypotheses are supported by phenotypic analysis of double mutants between ufo and other floral initiation and floral organ identity gene mutations. Surprisingly, in situ hybridization analysis revealed no obvious differences in mRNA levels or pattern for any organ identity gene examined. These results suggest that UFO may act post-transcriptionally to regulate the expression of floral organ identity genes. UFO was cloned by homology to the Antirrhinum gene FIMBR1ATA. Sequence analysis revealed no homology to any other gene in the sequence databases. UFO transcription is detected in spatial/temporal patterns consistent with its proposed roles in shoot and organ identity gene regulation, and does not appear to rely directly on any of the floral initiation genes. Collectively, the data indicate that UFO is required as part of the floral initiation process to establish the proper domains of shoot and organ identity gene function, and that this regulation occurs post-transcriptionally.
Behaviour change interventions for more sustainable food consumption A review of three REWE International cases studies
Creators: name: Dörrich, Jan
name: Kastenhofer, Klaus
name: Gorton, Matthew
name: Lemke, Fred
name: Nicolau, Mariana
name: Bethge, Jan
Publisher: name: Zenodo
Year: 2021

description: The overall goal of the VALUMICS project is to provide European decision makers with a comprehensive suite of approaches and tools to evaluate the impact of policies and strategies for enhancing the resilience, integrity and sustainability of food value chains in Europe. Contributing to the project goal, this report is the third in a series of VALUMICS outputs dedicated to food consumption analysis, aimed at understanding opportunities and challenges to drive food consumption behaviour change interventions in the food retail sector. This is done by analysing and learning from three pilot cases conducted by the VALUMICS project partner REWE International AG. In this context, Chapter 2 reviews the reasons for intention-behaviour gaps in relation to sustainable food consumption among consumers as well as the strategies that retailers may adopt to support change. Chapter 3 presents the three case studies conducted by REWE International as part of their sustainability portfolio and discusses their contribution to more sustainable food consumption and to more sustainable food value chains overall. Each case illustrates a particular strategy for retailer-led
 behavioural change, namely choice editing (social standards), choice expansion (returnable milk bottle) and choice environment (greening of stores). Chapter 4 presents conclusions from the cases, drawing out seven lessons for food retailer-led strategies. In addition to this report, VALUMICS project hosted a webinar on 19 November 2020 providing stakeholders with insights and information under the theme of this report. The video and slide presentations are accessible from the website of VALUMICS: EAT@Home – Putting solutions in the shopping basket. Food retailer approaches and interventions to support more sustainable food consumption.
description: Dorrich, J., Kastenhofer, K, Gorton, M., Lemke, F., Nicolau, M., Bethge Jan. (2021). Behaviour Change Interventions for More Sustainable Food Consumption. A review of three REWE International cases studies. VALUMICS "Understanding Food Value Chains and Network Dynamics", funded by European Union's Horizon 2020 research and innovation programme GA No 727243. CSCP, Germany, 48 pages.
Using quantum key distribution for cryptographic purposes: a survey
Creators: name: Alléaume, Romain
name: Branciard, Cyril
name: Bouda, Jan
name: Debuisschert, Thierry
name: Dianati, Mehrdad
name: Gisin, Nicolas
name: Godfrey, Mark
name: Grangier, Philippe
name: Langer, Thomas
name: Lutkenhaus, Norbert
name: Monyk, Christian
name: Painchault, Philippe
name: Peev, Momtchil
name: Poppe, Andreas
name: Pornin, Thomas
name: Rarity, John
name: Renner, Renato
name: Ribordy, Gregoire
name: Riguidel, Michel
name: Salvail, Louis
name: Shields, Andrew
name: Weinfurter, Harald
name: Zeilinger, Anton
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: Cryptography and Security (cs.CR)
subject: Information Theory (cs.IT)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: The appealing feature of quantum key distribution (QKD), from a cryptographic viewpoint, is the ability to prove the information-theoretic security (ITS) of the established keys. As a key establishment primitive, QKD however does not provide a standalone security service in its own: the secret keys established by QKD are in general then used by a subsequent cryptographic applications for which the requirements, the context of use and the security properties can vary. It is therefore important, in the perspective of integrating QKD in security infrastructures, to analyze how QKD can be combined with other cryptographic primitives. The purpose of this survey article, which is mostly centered on European research results, is to contribute to such an analysis. We first review and compare the properties of the existing key establishment techniques, QKD being one of them. We then study more specifically two generic scenarios related to the practical use of QKD in cryptographic infrastructures: 1) using QKD as a key renewal technique for a symmetric cipher over a point-to-point link; 2) using QKD in a network containing many users with the objective of offering any-to-any key establishment service. We discuss the constraints as well as the potential interest of using QKD in these contexts. We finally give an overview of challenges relative to the development of QKD technology that also constitute potential avenues for cryptographic research.
description: Revised version of the SECOQC White Paper. Published in the special issue on QKD of TCS, Theoretical Computer Science (2014), pp. 62-81
Star Formation Histories of Nearby Elliptical Galaxies. II. Merger Remnant Sample
Creators: name: Howell, Justin H.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: This work presents high $S/N$ spectroscopic observations of a sample of six suspected merger remnants, selected primarily on the basis of H{\sc i} tidal debris detections. Single stellar population analysis of these galaxies indicates that their ages, metallicities, and $α$-enhancement ratios are consistent with those of a representative sample of nearby elliptical galaxies. The expected stellar population of a recent merger remnant, young age combined with low [$α$/Fe], is not seen in any H{\sc i}-selected galaxy. However, one galaxy (NGC~2534), is found to deviate from the $Z$-plane in the sense expected for a merger remnant. Another galaxy (NGC~7332), selected by other criteria, best matches the merger remnant expectations.
description: 12 pages, 10 figures, accepted by AJ
The Pseudo-orthogonality for Graph $1$-Laplacian Eigenvectors and Applications to Higher Cheeger Constants and Data Clustering
Creators: name: Esposito, Antonio Corbo
name: Piscitelli, Gianpaolo
Publisher: name: arXiv
Year: 2021
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 05C10, 47J10, 49R05

description: The data clustering problem consists in dividing a data set into prescribed groups of homogeneous data. This is a NP-hard problem that can be relaxed in the spectral graph theory, where the optimal cuts of a graph are related to the eigenvalues of graph $1$-Laplacian. In this paper, we firstly give new notations to describe the paths, among critical eigenvectors of the graph $1$-Laplacian, realizing sets with prescribed genus.
 We introduce the pseudo-orthogonality to characterize $m_3(G)$, a special eigenvalue for the graph $1$-Laplacian. Furthermore, we use it to give an upper bound for the third graph Cheeger constant $h_3(G)$, that is $h_3(G) \le m_3(G)$. This is a first step for proving that the $k$-th Cheeger constant is the minimum of the $1$-Laplacian Raylegh quotient among vectors that are pseudo-orthogonal to the vectors realizing the previous $k-1$ Cheeger constants.
 Eventually, we apply these results to give a method and a numerical algorithm to compute $m_3(G)$, based on a generalized inverse power method.
description: 28 pages
Approximating General Metric Distances Between a Pattern and a Text
Creators: name: Efremenko, Klim
name: Porat, Ely
Publisher: name: arXiv
Year: 2008
Subjects: subject: Data Structures and Algorithms (cs.DS)
subject: FOS: Computer and information sciences

description: Let $T=t_0 ... t_{n-1}$ be a text and $P = p_0 ... p_{m-1}$ a pattern taken from some finite alphabet set $Σ$, and let $\dist$ be a metric on $Σ$. We consider the problem of calculating the sum of distances between the symbols of $P$ and the symbols of substrings of $T$ of length $m$ for all possible offsets. We present an $ε$-approximation algorithm for this problem which runs in time $O(\frac{1}{ε^2}n\cdot \mathrm{polylog}(n,\absΣ))$
description: This is updated version of paper appered in SODA 2008
Computational Study of Structural and Optical Properties of Metal Alkynyl Complexes
Creators: name: Kodikara, Mahesh Sanjaya
Publisher: name: Canberra, ACT : The Australian National University
Year: 2017
Subjects: Density functional calculations
Nonlinear optics
Excitation energy
Organometallics
Transition metals

description: The interaction of light with a nonlinear optical (NLO) material gives rise to new optical fields with altered properties (e.g. phase, frequency, amplitude, polarization, path, etc.), which are of utmost importance for photonic applications. The search for new efficient NLO materials for applications has thus been accelerated. In particular, interest in the NLO properties of organometallic systems has undergone enormous growth in the past decade. This thesis consists of a compilation of several papers relating to the experimental and density functional theory (DFT) studies of the nonlinear optical properties of metal alkynyl complexes. Paper 1 includes a brief introduction to nonlinear optical phenomena, in particular to the second-order NLO effects, and the popular experimental and quantum chemical methods for the determination of molecular first hyperpolarizability. It also includes a comprehensive review of previous semi empirical and DFT NLO calculations relating to organometallic complexes. Paper 2 deals with the benchmarking of DFT methods for first hyperpolarizabilities and excitation energies of metal alkynyls against the relevant experimental data. Papers 3-9 are combined experimental and computational (DFT) studies of dipolar (paper 3-8) and octupolar (paper 9) metal alkynyl complexes. The contribution from the calculations to each paper is as follows. In paper 3, linear optical and quadratic nonlinear optical properties of alkynyl complexes with different ligated metal centres (Ru, Ni, and Au) and with different bridges (phenylene, naphthalenylene, and anthracenylene) are calculated with DFT and time dependent DFT (TD-DFT). In paper 4, the linear optical and quadratic nonlinear optical properties of ruthenium alkynyl complexes with oligo(phenylenevinylene) bridges were calculated using DFT and the results compared with the experimental data. In paper 5, the experimentally determined linear optical properties and first hyperpolarizabilities of some ruthenium alkynyl complexes with yne/ene/azo inter-ring linkers are rationalized by DFT/TD-DFT calculations. In paper 6, the structural, linear optical, and nonlinear optical properties of ruthenium alkynyl complexes with P–P (= dppf, dppb, and dppe) and N–N (4,4’-di-tert-butyl-2,2’-bipyridine) donor co-ligands were rationalized from DFT calculations. Paper 7 consists of TD-DFT calculations undertaken on a series of bis(alkynyl) Ru complexes to rationalize the experimental linear optical data. In paper 8, the mechanism of two-dimensional NLO character in Y-shaped ruthenium alkynyl complexes is studied with the use of DFT/TD-DFT calculations. In paper 9, computational studies were undertaken to assign the key optical transitions for some octupolar compounds bearing (N-heterocyclic carbene) gold or diphenylamino substituents at the periphery.
Lazy Parameter Tuning and Control: Choosing All Parameters Randomly From a Power-Law Distribution
Creators: name: Antipov, Denis
name: Buzdalov, Maxim
name: Doerr, Benjamin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Neural and Evolutionary Computing (cs.NE)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Most evolutionary algorithms have multiple parameters and their values drastically affect the performance. Due to the often complicated interplay of the parameters, setting these values right for a particular problem (parameter tuning) is a challenging task. This task becomes even more complicated when the optimal parameter values change significantly during the run of the algorithm since then a dynamic parameter choice (parameter control) is necessary.
 In this work, we propose a lazy but effective solution, namely choosing all parameter values (where this makes sense) in each iteration randomly from a suitably scaled power-law distribution. To demonstrate the effectiveness of this approach, we perform runtime analyses of the $(1+(λ,λ))$ genetic algorithm with all three parameters chosen in this manner. We show that this algorithm on the one hand can imitate simple hill-climbers like the $(1+1)$ EA, giving the same asymptotic runtime on problems like OneMax, LeadingOnes, or Minimum Spanning Tree. On the other hand, this algorithm is also very efficient on jump functions, where the best static parameters are very different from those necessary to optimize simple problems. We prove a performance guarantee that is comparable to the best performance known for static parameters. For the most interesting case that the jump size $k$ is constant, we prove that our performance is asymptotically better than what can be obtained with any static parameter choice. We complement our theoretical results with a rigorous empirical study confirming what the asymptotic runtime results suggest.
description: Extended version of the paper that appeared at GECCO 2021. To appear in Algorithmica
Car conversation
Creators: name: Intanai, Thongwilai
name: Naknual, Prasopchok
name: Thawichart, Rungphithak
name: Thawichart, Somphong
name: Lau-Preechathammarach, Raksit Tyler
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2023
Subjects: subject: kdt

description: Traveling to and from Luang Pusruang (หลวงปู่สรวง) and Chong Sangam (ช่องซะงาม), on the border with Cambodia. Recorder: Zoom H4n. Microphone: internal.
On the efficient parallel computing of long term reliable trajectories for the Lorenz system
Creators: name: Hristov, I.
name: Hristova, R.
name: Dimova, S.
name: Armyanov, P.
name: Shegunov, N.
name: Puzynin, I.
name: Puzynina, T.
name: Sharipov, Z.
name: Tukhliev, Z.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: Mathematical Software (cs.MS)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: G.1.7; G.1.0
subject: 65L05, 65Y05

description: In this work we propose an efficient parallelization of multiple-precision Taylor series method with variable stepsize and fixed order. For given level of accuracy the optimal variable stepsize determines higher order of the method than in the case of optimal fixed stepsize. Although the used order of the method is greater then that in the case of fixed stepsize, and hence the computational work per step is greater, the reduced number of steps gives less overall work. Also the greater order of the method is beneficial in the sense that it increases the parallel efficiency. As a model problem we use the paradigmatic Lorenz system. With 256 CPU cores in Nestum cluster, Sofia, Bulgaria, we succeed to obtain a correct reference solution in the rather long time interval - [0,11000]. To get this solution we performed two large computations: one computation with 4566 decimal digits of precision and 5240-th order method, and second computation for verification - with 4778 decimal digits of precision and 5490-th order method.
description: 10 pages, 2 figures. arXiv admin note: text overlap with arXiv:2010.14993
Projectively flat KLT varieties
Creators: name: Greb, Daniel
name: Kebekus, Stefan
name: Peternell, Thomas
Publisher: name: arXiv
Year: 2020
Subjects: subject: Algebraic Geometry (math.AG)
subject: Complex Variables (math.CV)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 32Q30, 32Q26, 14E20, 14E30, 53B10

description: In the context of uniformisation problems, we study projective varieties with klt singularities whose cotangent sheaf admits a projectively flat structure over the smooth locus. Generalising work of Jahnke-Radloff, we show that torus quotients are the only klt varieties with semistable cotangent sheaf and extremal Chern classes. An analogous result for varieties with nef normalised cotangent sheaves follows.
On the S-matrix of Liouville theory
Creators: name: Jorjadze, George
name: Theisen, Stefan
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The S-matrix for each chiral sector of Liouville theory on a cylinder is computed from the loop expansion of correlation functions of a one-dimensional field theory on a circle with a non-local kinetic energy and an exponential potential. This action is the Legendre transform of the generating function of semiclassical scattering amplitudes. It is derived from the relation between asymptotic in- and out-fields. Its relevance for the quantum scattering process is demonstrated by comparing explicit loop diagrams computed from this action with other methods of computing the S-matrix, which are also developed.
N-flationary magnetic fields
Creators: name: Anber, Mohamed M.
name: Sorbo, Lorenzo
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: There is increasing interest in the role played by pseudo Nambu-Goldstone bosons (pNGBs) in the construction of string-inspired models of inflation. In these models the inflaton is expected to be coupled to gauge fields, and will lead to the generation of magnetic fields that can be of cosmological interest. We study the production of such fields mainly focusing on the model of N-flation, where the collective effect of several pNGBs drives inflation. Because the produced fields are maximally helical, inverse cascade processes in the primordial plasma increase significantly their coherence length. We discuss under what conditions inflation driven by pNGBs can account for the observed cosmological magnetic fields. A constraint on the parameters of this class of inflationary scenarios is also derived by requiring that the magnetic field does not backreact on the inflating background.
description: 13pages, minor corrections, references added, final version to be published in JCAP
An Extended Jump Functions Benchmark for the Analysis of Randomized Search Heuristics
Creators: name: Bambury, Henry
name: Bultel, Antoine
name: Doerr, Benjamin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Neural and Evolutionary Computing (cs.NE)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Jump functions are the {most-studied} non-unimodal benchmark in the theory of randomized search heuristics, in particular, evolutionary algorithms (EAs). They have significantly improved our understanding of how EAs escape from local optima. However, their particular structure -- to leave the local optimum one can only jump directly to the global optimum -- raises the question of how representative such results are.
 For this reason, we propose an extended class $\textsc{Jump}_{k,δ}$ of jump functions that contain a valley of low fitness of width $δ$ starting at distance $k$ from the global optimum. We prove that several previous results extend to this more general class: for all {$k \le \frac{n^{1/3}}{\ln{n}}$} and $δ< k$, the optimal mutation rate for the $(1+1)$~EA is $\fracδ{n}$, and the fast $(1+1)$~EA runs faster than the classical $(1+1)$~EA by a factor super-exponential in $δ$. However, we also observe that some known results do not generalize: the randomized local search algorithm with stagnation detection, which is faster than the fast $(1+1)$~EA by a factor polynomial in $k$ on $\textsc{Jump}_k$, is slower by a factor polynomial in $n$ on some $\textsc{Jump}_{k,δ}$ instances.
 Computationally, the new class allows experiments with wider fitness valleys, especially when they lie further away from the global optimum.
description: Extended version of a paper that appeared in the proceedings of GECCO 2021. To appear in Algorithmica
The life and works of Alexander Ivanovich Ertel (1855-1908) : whither Russia?
Creators: name: Griffin, Steven Richard
Publisher: name: University of British Columbia
Year: 2009

description: Three principal aspects of A.I. Ertel's (1855-1908) art are considered in this reassessment of his life and works. The first is his religious ethnography, whereby he represents the felt quality of the religious revival of his time in all its diversity. The second aspect is the dialogue which his works form with the question of national destiny. The third is the spiritual autobiography which his oeuvre represents. Accordingly, the approach taken in this study is, from one perspective, historical and biographical, while from another it will make use of M. Bakhtin's notion of "polyphonic artistic thinking" in analyzing Ertel's works. It is the third aspect of Ertel' s art which gives this thesis its structure. In Part I, "Confrontation," representative early works are considered within the context of three philosophical confrontations: first, with the notion that the meaning of life is self-evident; second, with philosophical pessimism; and third, with Tolstoyism. Part Two is devoted to two novels which reflect Ertel's philosophy of "Compromise." These works present a hopeful view of both individual and corporate moral development in spite of diversity and sweeping social change. Part Three, "Counter Idea," examines two works which reflect the author's ultimate dissatisfaction with "all-embracing theories" in these works Ertel confronts the reader with reasons for hope and despair with regard to progress and the destiny of Russia. The Conclusion attempts to re-establish Ertel's place in Russian literature, giving consideration to the relevance of his works for today and to his particular narrative style.
A physical method for investigating defect chemistry in solid metal oxides
Creators: name: Rodenbücher, Christian
name: Korte, Carsten
name: Schmitz-Kempen, Thorsten
name: Bette, Sebastian
name: Szot, Kristof
Publisher: name: arXiv
Year: 2020
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The investigation of the defect chemistry of solid oxides is of central importance for the understanding of redox processes. This can be performed by measuring conductivity as a function of the oxygen partial pressure, which is conventionally established by using buffer gas mixtures or oxygen pumps based on zirconia. However, this approach has some limitations, such as difficulty regulating oxygen partial pressure in some intermediate-pressure regions or the possibility of influencing the redox process by gases that can also be incorporated into the oxide or react with the surface via heterogeneous catalysis. Herein, we present an alternative physical method in which the oxygen partial pressure is controlled by dosing pure oxygen inside an ultra-high vacuum chamber. To monitor the conductivity of the oxide under investigation, we employ a dedicated four-probe measurement system that relies on the application of a very small AC voltage, in combination with lock-in data acquisition using highly sensitive electrometers, minimizing the electrochemical polarization or electro-reduction and degradation effects. By analyzing the model material SrTiO3, we demonstrate that its characteristic redox behavior can be reproduced in good agreement with the theory when performing simultaneous electrical conductivity relaxation (ECR) and high-temperature equilibrium conductivity (HTEC) measurements. We show that the use of pure oxygen allows for a direct analysis of the characteristic oxygen dose, which opens up various perspectives for a detailed analysis of the surface chemistry of redox processes.
description: 25 pages