cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
An Empty Promise? Digital Democracy in the Smart City
Creators: name: Willers, Rabea
Publisher: name: University of Westminster
Year: 2022

description: The digital transformation affects every part of our societies and everyday lives, including the processes and structures of our democracies. On the one hand, information and communication technologies have the potential to lower the threshold for political communication and participation. On the other hand, they can be used for large-scale data collection and surveillance, posing a risk to the public sphere. This thesis investigates the impact of digitization on the legitimacy of democracy. It first develops a novel framework based on the theories of participatory and deliberative democracy, drawing on recent work on deliberative systems. On this basis, digital democracy is examined as a system, consisting of different engagement spaces and actors within the smart city. The smart city is a particularly fruitful testbed for digital democracy as it is based on the promise of applying a high density of digital technologies to facilitate civic participation as well as better service delivery and governance. Through an in-depth case study of the smart city of Amsterdam, this thesis not only reveals the legitimacy dilemmas of digital democracy in the smart city, but also illustrates the limits of applying participatorydeliberative systems theory on a digital democracy ecosystem. The analysis demonstrates design conflicts between different online engagement platforms within the digital democracy system, as well as conflicting objectives among the actors behind them. The findings do not support the claim that digitization negatively impacts democracy’s legitimacy in the smart city of Amsterdam through marketization, large-scale data collection, and surveillance, as some authors warn. However, a significant positive impact of digitization on democratic legitimacy, through higher levels of inclusiveness, empowerment, or civic influence, is also not confirmed. The findings show that digital technologies’ promise of facilitating large-scale citizen participation and deliberation in the smart city does not live up to the normative ideal. The results from Amsterdam are exposed to smart city and digital democracy experts across the globe to test their generalizability, demonstrating that, despite its shortcomings, Amsterdam’s extensive digital democracy system is far advanced in international comparison. What may appear a contradiction in fact illustrates that we are still in the early stages of development, with potential to enhance the legitimacy of digital democracy, both in the smart city of Amsterdam and beyond.
Quantum groups and noncommutative spacetimes with cosmological constant
Creators: name: Ballesteros, A.
name: Gutiérrez-Sagredo, I.
name: Herranz, F. J.
name: Meusburger, C.
name: Naranjo, P.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: Noncommutative spacetimes are widely believed to model some properties of the quantum structure of spacetime at the Planck regime. In this contribution the construction of (anti-)de Sitter noncommutative spacetimes obtained through quantum groups is reviewed. In this approach the quantum deformation parameter $z$ is related to a Planck scale, and the cosmological constant $Λ$ plays the role of a second deformation parameter of geometric nature, whose limit $Λ\to 0$ provides the corresponding noncommutative Minkowski spacetimes.
description: 10 pages. Based on the contribution presented at "Eighth International Workshop DICE2016", Castello Pasquini in Castiglioncello, Italy, September 12-16, 2016
CAST STM Open Access Publishing in China 2022-English
Creators: name: Robertson, Mark
name: STM, international Association of STM Publishers
name: CAST, China Association for Science and Technology
Publisher: name: figshare
Year: 2022
Subjects: Communication technology and digital media studies

description: China Association for Science and Technology (CAST) and International Association of STM Publishers (STM) Report on Open Access in China, 2022
A quantum linear system algorithm for dense matrices
Creators: name: Wossnig, Leonard
name: Zhao, Zhikuan
name: Prakash, Anupam
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Solving linear systems of equations is a frequently encountered problem in machine learning and optimisation. Given a matrix $A$ and a vector $\mathbf b$ the task is to find the vector $\mathbf x$ such that $A \mathbf x = \mathbf b$. We describe a quantum algorithm that achieves a sparsity-independent runtime scaling of $\mathcal{O}(κ^2 \|A\|_F \text{polylog}(n)/ε)$, where $n\times n$ is the dimensionality of $A$ with Frobenius norm $\|A\|_F$, $κ$ denotes the condition number of $A$, and $ε$ is the desired precision parameter. When applied to a dense matrix with spectral norm bounded by a constant, the runtime of the proposed algorithm is bounded by $\mathcal{O}(κ^2\sqrt{n} \text{polylog}(n)/ε)$, which is a quadratic improvement over known quantum linear system algorithms. Our algorithm is built upon a singular value estimation subroutine, which makes use of a memory architecture that allows for efficient preparation of quantum states that correspond to the rows and row Frobenius norms of $A$.
Without data, science is merely an opinion: the African Open Science Platform project
Creators: name: Smith, Ina
Publisher: name: My University
Year: 2017

description: The Science International Accord on Open Data in a Big Data World presents an inclusive vision of the need for and the benefits of Open Data for science internationally, and in particular for Lower and Middle Income Countries. In addition to benefiting from Data from the international community, African countries have much to contribute for all to benefit in making progress towards implementing the United Nations Development Programme (UNDP) Sustainable Development Goals (SDGs), provided that Data curation activities are aligned with international standards. Providing a comprehensive view of what is happening on national and continental level, will not only assist fellow researchers and potential funders in identifying gaps – it will also assist African countries to identify opportunities for capacity building, inter-regional links to strengthen collaboration, towards international alignment with science activities on international level. The African Open Science Platform initiative is an important outcome of the Accord on Open Data in a Big Data World, and great progress has been made towards a better understanding of the following four focus areas: 1) buy-in and support from countries and institutions through data policies; 2) capacity building and developing skills; 3) how sharing of data by researchers is awarded (incentives); and 4) current infrastructures that exist to support the sharing of data. This presentation will be focusing on the alignment of the project with the SDGs, as well as sharing outcomes of the project regarding the mentioned focus areas. Phase 1 of this project focused on creating awareness and doing a landscape survey of what is done in terms of Open Data. Phase 2 – starting on 1 November 2017 – will be focusing on building capacity and presenting training workshops. Initiatives indicated above are captured in a database, which will inform future recommendations. This platform is expected to enhance accessibility to and increase the impact of African science, and specifically the data sets underlying the science.
Developing Effective Public Awareness Communication Strategy to Stimulate the Role of NRENs in Intra- African Collaboration Strategies
Creators: name: Kinyera-Apuke, George
Publisher: name: My University
Year: 2017

description: We explain developing effective public awareness communication strategy will help to stimulate the role of NRENs s well as the regional RENs to spur the current and projected intra- African collaboration strategies for enhanced research and education outputs. The main objectives are to: review the role or benefits of public awareness communication strategy in promoting intra-regional networking for enhanced research, education, and public outreach services; discuss the social responsibility of the media (press) to crate or raise public awareness of the need to enhance the national and regional integration of research and education networks for improved performance outputs on the African continent. In this review, we examined the roles of national and regional regulators of research and education institutions and networks, NRENs, regional RENs, and institutions themselves in developing collaborative programmes or strategies. More data were sourced from policy documents on the strategies, methods, status, and outputs of collaboration goals. Additional information was obtained from internet searches on the role of governments, status of shared infrastructure services, resource access or use; cost effectiveness, as well as the roles of NRENs; the roles of the regional RENs in stimulating their optimal effectiveness, efficiency, and investment expansion. Key words: Africa, regional RENs, NRENs, collaboration, networking, strategic plan, Uganda
Mott transitions with partially-filled correlated orbitals
Creators: name: Amaricci, Adriano
name: Medici, Luca de'
name: Capone, Massimo
Publisher: name: arXiv
Year: 2016
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We investigate the metal-insulator Mott transition in a generalized version of the periodic Anderson model, in which a band of itinerant electrons is hybridrized with a narrow and strongly correlated band. Using dynamical mean-field theory, we show that the precondition for a Mott transition is an integer total filling of the two bands, while for an integer constant occupation of the correlated band the system remains a correlated metal at arbitrary large interaction strength. We picture the transition at a non-integer filling of the correlated orbital as the Mott localization of the singlet states between itinerant and strongly interacting electrons, having occupation of one per lattice site. We show that the Mott transition is of the first-order and we characterize the nature of the resulting insulating state with respect to relevant physical parameters, such as the charge-transfer energy.
description: 5 pages, 4 figures
CAST STM Open Access Publishing in China 2022-EnglishEdition-final
Creators: name: Robertson, Mark
name: STM, international Association of STM Publishers
name: CAST, China Association for Science and Technology
Publisher: name: figshare
Year: 2022
Subjects: Communication technology and digital media studies

description: Chinese Association for Science and Technology (CAST) and International Association of STM Publishers (STM) Report on Open Access in China, 2022
Jointly Learning Sentence Embeddings and Syntax with Unsupervised Tree-LSTMs
Creators: name: Maillard, Jean
name: Clark, Stephen
name: Yogatama, Dani
Publisher: name: arXiv
Year: 2017
Subjects: subject: Computation and Language (cs.CL)
subject: FOS: Computer and information sciences

description: We introduce a neural network that represents sentences by composing their words according to induced binary parse trees. We use Tree-LSTM as our composition function, applied along a tree structure found by a fully differentiable natural language chart parser. Our model simultaneously optimises both the composition function and the parser, thus eliminating the need for externally-provided parse trees which are normally required for Tree-LSTM. It can therefore be seen as a tree-based RNN that is unsupervised with respect to the parse trees. As it is fully differentiable, our model is easily trained with an off-the-shelf gradient descent method and backpropagation. We demonstrate that it achieves better performance compared to various supervised Tree-LSTM architectures on a textual entailment task and a reverse dictionary task.
Building and testing models with extended Higgs sectors
Creators: name: Ivanov, Igor P.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Models with non-minimal Higgs sectors represent a mainstream direction in theoretical exploration of physics opportunities beyond the Standard Model. Extended scalar sectors help alleviate difficulties of the Standard Model and lead to a rich spectrum of characteristic collider signatures and astroparticle consequences. In this review, we introduce the reader to the world of extended Higgs sectors. Not pretending to exhaustively cover the entire body of literature, we walk through a selection of the most popular examples: the two- and multi-Higgs-doublet models, as well as singlet and triplet extensions. We will show how one typically builds models with extended Higgs sectors, describe the main goals and the challenges which arise on the way, and mention some methods to overcome them. We will also describe how such models can be tested, what are the key observables one focuses on, and illustrate the general strategy with a subjective selection of results.
description: 57 pages + 32-page bibliography, 10 figures; invited review for Progress in Particle and Nuclear Physics; v2: minor modifications, extra references
A Unified Framework for Constructing, Tuning and Assessing Photometric Redshift Density Estimates in a Selection Bias Setting
Creators: name: Freeman, Peter E.
name: Izbicki, Rafael
name: Lee, Ann B.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Photometric redshift estimation is an indispensable tool of precision cosmology. One problem that plagues the use of this tool in the era of large-scale sky surveys is that the bright galaxies that are selected for spectroscopic observation do not have properties that match those of (far more numerous) dimmer galaxies; thus, ill-designed empirical methods that produce accurate and precise redshift estimates for the former generally will not produce good estimates for the latter. In this paper, we provide a principled framework for generating conditional density estimates (i.e. photometric redshift PDFs) that takes into account selection bias and the covariate shift that this bias induces. We base our approach on the assumption that the probability that astronomers label a galaxy (i.e. determine its spectroscopic redshift) depends only on its measured (photometric and perhaps other) properties x and not on its true redshift. With this assumption, we can explicitly write down risk functions that allow us to both tune and compare methods for estimating importance weights (i.e. the ratio of densities of unlabeled and labeled galaxies for different values of x) and conditional densities. We also provide a method for combining multiple conditional density estimates for the same galaxy into a single estimate with better properties. We apply our risk functions to an analysis of approximately one million galaxies, mostly observed by SDSS, and demonstrate through multiple diagnostic tests that our method achieves good conditional density estimates for the unlabeled galaxies.
description: 11 pages; accepted by MNRAS
Digital Tools for Collaborative Research
Creators: name: Mapanga, Innocent
Publisher: name: My University
Year: 2017

description: Collaboration in research facilitate connecting researchers, exploration of literature, collaborative writing, publishing, evaluation, finding and sharing of data and code amongst a lot many research activities. A collection of digital tools are needed to support collaborative research efforts from research tasks ranging from search to article visualization so as to enhance reading, writing and navigation experience for researchers. Researchers stationed in different institutions and regions of the world are increasingly reaching out to connect with experts as well as other researchers to solve different problems facing governments of the world. This calls for tools that support collaboration such as in the creation of electronic lab notebooks, mind mapping, generation and analysis of data sets, which serve as the nervous system that provision services that support meaningful collaborative activities. Digital tools supporting outsourcing of experiments and connecting instruments and sharing of development platforms through virtual environments have come in hand in strengthening collaborative research. In this era of collaborative research writing, research writing tools have become a requirement especially those able to adapt to the needs of researchers to enable storage and management of references facilitating writing of manuscripts while keeping a close track in the modifications by others to the text. Evaluating research enables scientific value of articles and overall achievements of researchers to be known through peer reviews. Digital Tools that analyse impact of one’s research to check impact factor and citation counts help researchers visualize the impact of their research. In this research work, we will analyse the various digital tools supporting collaborative research and how they assist the various collaborative research activities. Furthermore, we will establish tools that researchers are still yearning for, that need to be developed to help them in undertaking their research activities which are currently not covered by existing digital research tools.
Test of SensL SiPM coated with NOL-1 wavelength shifter in liquid xenon
Creators: name: Akimov, D. Yu.
name: Belov, V. A.
name: Borshchev, O. V.
name: Burenkov, A. A.
name: Grishkin, Yu. L.
name: Karelin, A. K.
name: Kuchenkov, A. V.
name: Martemiyanov, A. N.
name: Ponomarenko, S. A.
name: Simakov, G. E.
name: Stekhanov, V. N.
name: Surin, N. M.
name: Timoshin, V. S.
name: Zeldovich, O. Ya.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: A SensL MicroFC-SMT-60035 6x6 mm$^2$ silicon photo-multiplier coated with a NOL-1 wavelength shifter have been tested in the liquid xenon to detect the 175-nm scintillation light. For comparison, a Hamamatsu vacuum ultraviolet sensitive MPPC VUV3 3x3 mm$^2$ was tested under the same conditions. The photodetection efficiency of $13.1 \pm 2.5$% and $6.0 \pm 1.0$%, correspondingly, is obtained.
description: 8 pages, 4 figures
MPEC 2023-R95 : 2019 QK4
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Dispersion-optimized quadrature rules for isogeometric analysis: modified inner products, their dispersion properties, and optimally blended schemes
Creators: name: Puzyrev, Vladimir
name: Deng, Quanling
name: Calo, Victor
Publisher: name: arXiv
Year: 2016
Subjects: subject: Numerical Analysis (math.NA)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: This paper introduces optimally-blended quadrature rules for isogeometric analysis and analyzes the numerical dispersion of the resulting discretizations. To quantify the approximation errors when we modify the inner products, we generalize the Pythagorean eigenvalue theorem of Strang and Fix. The proposed blended quadrature rules have advantages over alternative integration rules for isogeometric analysis on uniform and non-uniform meshes as well as for different polynomial orders and continuity of the basis. The optimally-blended schemes improve the convergence rate of the method by two orders with respect to the fully-integrated Galerkin method. The proposed technique increases the accuracy and robustness of isogeometric analysis for wave propagation problems.
Hybrid-electric propulsion concept design for shortmedium range aircraft
Creators: name: Vankan, Jos
name: Lammen, Wim
Publisher: name: Zenodo
Year: 2022
Subjects: IMOTHEP
green aviation
hybrid-electric aircraft
H2020 Transport
electric aircraft
hybrid electric propulsion
CINEA

description: Presentation at Workshop on Innovative Scientific / Technical Approaches for a Climate Neutral Air Transport, Barcelona, Spain, 22-24/11/22
Radiation hard pixel sensors using high-resistive wafers in a 150 nm CMOS processing line
Creators: name: Pohl, D. -L.
name: Hemperek, T.
name: Caicedo, I.
name: Gonella, L.
name: Hügging, F.
name: Janssen, J.
name: Krüger, H.
name: Macchiolo, A.
name: Owtscharenko, N.
name: Vigani, L.
name: Wermes, N.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Pixel sensors using 8" CMOS processing technology have been designed and characterized offering the benefits of industrial sensor fabrication, including large wafers, high throughput and yield, as well as low cost. The pixel sensors are produced using a 150 nm CMOS technology offered by LFoundry in Avezzano. The technology provides multiple metal and polysilicon layers, as well as metal-insulator-metal capacitors that can be employed for AC-coupling and redistribution layers. Several prototypes were fabricated and are characterized with minimum ionizing particles before and after irradiation to fluences up to 1.1 $\times$ 10$^{15}$ n$_{\rm eq}$ cm$^{-2}$. The CMOS-fabricated sensors perform equally well as standard pixel sensors in terms of noise and hit detection efficiency. AC-coupled sensors even reach 100% hit efficiency in a 3.2 GeV electron beam before irradiation.
description: 10 pages, 6 figures
Kraliçe I. Elizabeth ve İngiltere'nin Altın Çağı
Creators: name: Taşdemir, Berfin
Publisher: name: Zenodo
Year: 2023
Subjects: subject: I. Elizabeth
subject: Kraliçe Elizabeth
subject: Tudor Hanedanı
subject: https://www.researchgate.net/publication/371970843_Kralice_I_Elizabeth_ve_Ingiltere'nin_Altin_Cagi

description: İngiltere'nin en kanlı ve en yıpratıcı iç savaşlarından olan Güllerin Savaşı, Tudorların İngiliz tahtını ele geçirmesi ile sona ermiştir. İngiltere'nin güçlü bir monarşi haline gelmesine büyük katkıda bulunan Tudor hanedanından sadece beş hükümdar tahta çıksa da, bunlardan ikisi tarihe isimlerini yazdırabilmeyi başarmıştır. Babası VIII. Henry'nin kurduğu İngiltere Kilisesi'nin başına geçen ilk kadın olan Kraliçe Elizabeth, tarihe yön veren kadınlardan biri haline gelmiştir. Gerek yarattığı ve bugün hala oldukça popüler olan Bakire Kraliçe kültü, gerekse İngiltere'de uzun süre etkisi sürecek olan sanat ve kültürel yaşamın gelişmesine katkı sağlamış olması bakımından Elizabeth ülkesinde adeta bir efsane haline gelmiştir. Tüm dünyada patriyarkal sistemin görüldüğü bir toplum düzeninde ülkesini koruyan ve geliştiren bu kraliçe bir kadının da devlet yönetiminde başarılı olabileceğini göstererek kadın hükümdarlar için öncü olmuştur. İngiltere'nin Avrupa'nın en güçlü ülkesi İspanya'ya karşı kazandığı deniz zaferi, bir kadın olarak Elizabeth'in ne denli başarılı bir hükümdar olduğunu göstermektedir. Elizabeth'in sanata verdiği desteğin en önemli sonucu, bugün eserlerini hala keyifle okuduğumuz William Shakespeare ve Christopher Marlowe'un ortaya çıkmasını sağlamış olmasıdır.
Blockchain technology: Facilitating collaborative research via Intellectual Property sharing
Creators: name: Mpofu, Thabiso
Publisher: name: My University
Year: 2017

description: Blockchain is the underlying technology on which CryptoCurrencies such as Bitcoin and Etherium are based. Blockchain is implemented via the use of a distributed ledger. Blockchain ensures permanence of information and addition or modification is subject to everyone and the owner of information contained in the ledger agreeing as well thus making it temper proof. Transactions are grouped into blocks and time stamped and the whole mechanism is decentralised in nature and open to anyone and everyone. Many African countries currently do not have the requisite information sharing infrastructure in place. The use of blockchain technology will enable African and other developing countries to jump the technology gap. The current ledger systems where Intellectual property is adjudicated and stored (such as ARIPO) is centralised in nature. The storage and sharing of Intellectual property such as Patents could harness such technology as blockchain. Various academic, corporate and research institutions across the African continent and other developing countries can be able to share and access Intellectual Property inexpensively and thus effectively facilitating collaborative research.
Dynamical defects in rotating magnetic skyrmion lattices
Creators: name: Pöllath, S.
name: Wild, J.
name: Heinen, L.
name: Meier, T. N. G.
name: Kronseder, M.
name: Tutsch, L.
name: Bauer, A.
name: Berger, H.
name: Pfleiderer, C.
name: Zweck, J.
name: Rosch, A.
name: Back, C. H.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The chiral magnet Cu$_{2}$OSeO$_{3}$ hosts a skyrmion lattice, that may be equivalently described as a superposition of plane waves or lattice of particle-like topological objects. A thermal gradient may break up the skyrmion lattice and induce rotating domains raising the question which of these scenarios better describes the violent dynamics at the domain boundaries. Here we show that in an inhomogeneous temperature gradient caused by illumination in a Lorentz Transmission Electron Microscope different parts of the skyrmion lattice can be set into motion with different angular velocities. Tracking the time dependence we show that the constant rearrangement of domain walls is governed by dynamic 5-7 defects arranging into lines. An analysis of the associated defect density is described by Frank's equation and agrees well with classical 2D-Monte Carlo simulations. Fluctuations of boundaries show surge-like rearrangement of skyrmion clusters driven by defect rearrangement consistent with simulations treating skyrmions as point particles. Our findings underline the particle character of the skyrmion.
description: 6 pages, 4 figures, 6 supplement pages, 5 supplemental figures
Holographic Equilibration under External Dynamical Electric Field
Creators: name: Ali-Akbari, M.
name: Charmchi, F.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The holographic equilibration of a far-from-equilibrium strongly coupled gauge theory is investigated. The dynamics of a probe D7-brane in an AdS-Vaidya background is studied in the presence of an external time-dependent electric field. Defining the equilibration times $t_{eq}^c$ and $t_{eq}^j$, at which condensation and current relax to their final equilibrated values, receptively, the smallness of transition time $k_M$ or $k_E$ is enough to observe a universal behaviour for re-scaled equilibration times $k_M k_E (t_{eq}^c)^{-2}$ and $k_M k_E (t_{eq}^j)^{-2}$. Moreover, regardless of the values for $k_M$ and $k_E$, $t_{eq}^c/t_{eq}^j$ also behaves universally for large enough value of the ratio of the final electric field to final temperature. Then a simple discussion of the static case reveals that $t_{eq}^c \leq t_{eq}^j$. For an out-of-equilibrium process, our numerical results show that, apart from the cases for which $k_E$ is small, the static time ordering persists.
description: 6 pages, 8 figures
atomicrex - A general purpose tool for the construction of atomic interaction models
Creators: name: Stukowski, Alexander
name: Fransson, Erik
name: Mock, Markus
name: Erhart, Paul
Publisher: name: arXiv
Year: 2017
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We introduce atomicrex, an open-source code for constructing interatomic potentials as well as more general types of atomic-scale models. Such effective models are required to simulate extended materials structures comprising many thousands of atoms or more, because electronic structure methods become computationally too expensive at this scale. atomicrex covers a wide range of interatomic potential types and fulfills many needs in atomistic model development. As inputs, it supports experimental property values as well as \textit{ab initio} energies and forces, to which models can be fitted using various optimization algorithms. The open architecture of atomicrex allows it to be used in custom model development scenarios beyond classical interatomic potentials while thanks to its Python interface it can be readily integrated e.g., with electronic structure calculations or machine learning algorithms.
description: 11 pages; 1 figure
Improved laser linewidth estimation from self-heterodyne beat note measurements using parametric Wiener filters
Creators: name: Kantner, Markus
name: Mertenskötter, Lutz
Publisher: name: Weierstrass Institute
Year: 2022
Subjects: subject: Laser linewidth
subject: phase noise
subject: narrow-linewidth
subject: semiconductor lasers
subject: Wiener deconvolution
subject: self-heterodyne beat note measurement
subject: non-Markovian noise
subject: Langevin equations
subject: stochastic differential equations
subject: 37N20
subject: 60G10
subject: 60G35
subject: 62M20
subject: 82C31

description: Self-heterodyne beat note measurement techniques are widely used for the experimental char- acterization of the phase noise power spectral density (PSD) and the spectral linewidth of lasers. The measured data, however, must be corrected for the transfer function of the interferometer in a post-processing routine. The standard approach disregards the measurement noise and thereby induces uncontrolled artifacts in the reconstructed noise PSDs. We introduce an improved data post-processing routine based on a parametric Wiener filter (power spectrum equalization, PSE), that is potentially free of reconstruction artifacts provided a good estimate for the signal-to-noise ratio (SNR) is supplied. Based on the PSE filter, we describe a new method for the estimation of the intrinsic laser linewidth. Our method yields accurate estimates even in the case of strong measurement noise, where the intrinsic linewidth plateau is not visible using the standard method. We demonstrate the method using simulated data from a stochastic laser rate equation model.
Maximal temperature of the gas in AdS space-time
Creators: name: Dai, De-Chang
name: Stojkovic, Dejan
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Assuming only statistical mechanics and general relativity, we calculate the maximal temperature of gas of particles placed in AdS space-time. If two particles with a given center of mass energy come close enough, according to classical gravity they will form a black hole. We focus only on the black holes with Hawking temperature lower than the environment, because they do not disappear. The number density of such black holes grows with the temperature in the system. At a certain finite temperature, the thermodynamical system will be dominated by black holes. This critical temperature is lower than the Planck temperature for the values of the AdS vacuum energy density below the Planck density. This result might be interesting from the AdS/CFT correspondence point of view, since it is different from the Hawking-Page phase transition, and it is not immediately clear what effect dynamically limits the maximal temperature of the thermal state on the CFT side of the correspondence.
description: Published in Phys.Rev. D95 (2017) no.8, 085015
Atomic-scale structure analysis of a molecule at a (6-nanometer)$^3$ ice crystal
Creators: name: Kong, Xi
name: Shi, Fazhan
name: Yang, Zhiping
name: Wang, Pengfei
name: Raatz, Nicole
name: Meijer, Jan
name: Du, Jiangfeng
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: Water is the most important solvent in nature. It is a crucial issue to study interactions among water molecules. Nuclear magnetic resonance (NMR) spectroscopy is one of the most powerful tools to detect magnetic interactions for the structure analysis of a molecule with broad applications. But conventional NMR spectroscopy requires macroscopic sample quantities with hampers in investigating nanoscale structures. Through quantum control of a single spin quantum sensor, magnetic resonance spectroscopy of nanoscale organic molecules and single molecules has been achieved. However, the measurement of the dipolar interaction of nuclear spins within a molecule at nanoscale and the analysis of its structure remain a big challenge. Here we succeed in detecting the NMR spectrum from an ice crystal with (6-nanometer)$^3$ detection volume. More importantly, the magnetic dipolar coupling between two proton nuclear spins of a water molecule was recorded. The resolved intra-molecule magnetic dipolar interactions are about 15 kHz and 33 kHz with spectral resolution at a few kHz. Analysis of the interaction-resolved NMR spectroscopy provides a spatial view of nanoscale ice crystal, from which the orientation of a water-molecule bond is derived and further the length of the bond can be got. This work enables NMR spectroscopy applications in single molecule structure analysis, provides a further tool for nanocrystalline and confined water research.
MPEC 2023-R96 : 2019 QO5
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Testing general relativity by means of ringlasers
Creators: name: Tartaglia, Angelo
name: Di Virgilio, Angela
name: Belfi, Jacopo
name: Beverini, Nicolò
name: Ruggiero, Matteo Luca
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The paper discusses the optimal conguration of one or more ring lasers to be used for measuring the general relativistic effects of the rotation of the earth, as manifested on the surface of the planet. The analysis is focused on devices having their normal vector lying in the meridian plane. The crucial role of the evaluation of the angles is evidenced. Special attention is paid to the orientation at the maximum signal, minimizing the sensitivity to the orientation uncertainty. The use of rings at different latitudes is mentioned and the problem of the non-sfericity of the earth is commented.
description: 12 pages, 2 figures
Discriminative Transfer Learning for General Image Restoration
Creators: name: Xiao, Lei
name: Heide, Felix
name: Heidrich, Wolfgang
name: Schölkopf, Bernhard
name: Hirsch, Michael
Publisher: name: arXiv
Year: 2017
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Recently, several discriminative learning approaches have been proposed for effective image restoration, achieving convincing trade-off between image quality and computational efficiency. However, these methods require separate training for each restoration task (e.g., denoising, deblurring, demosaicing) and problem condition (e.g., noise level of input images). This makes it time-consuming and difficult to encompass all tasks and conditions during training. In this paper, we propose a discriminative transfer learning method that incorporates formal proximal optimization and discriminative learning for general image restoration. The method requires a single-pass training and allows for reuse across various problems and conditions while achieving an efficiency comparable to previous discriminative approaches. Furthermore, after being trained, our model can be easily transferred to new likelihood terms to solve untrained tasks, or be combined with existing priors to further improve image restoration quality.
Spiral determinants
Creators: name: Bhatnagar, Gaurav
name: Krattenthaler, Christian
Publisher: name: arXiv
Year: 2017
Subjects: subject: Combinatorics (math.CO)
subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 15A15 (Primary), 05A10 11C20 (Secondary)

description: We evaluate determinants of "spiral" matrices, which are matrices in which entries are spiralling from the centre of the matrices towards the outside, with prescribed increments from one entry to the next depending on whether one moves right, up, left, or down along the spiral.
description: AmS-TeX, 16 pages
Datos Abiertos y Planes de Gestión de Datos
Creators: name: Gallardo-Ferreira, Fabian Octavio Alejandro
Publisher: name: Zenodo
Year: 2023
Subjects: open data
data management plan
datos abiertos
plan de gestión de datos

description: En el contexto del Proyecto INCA 210024 - UFRO de la ANID y sus planes de formación para la Facultad de Ciencia Jurídicas y Empresariales de la Universidad de La Frontera, se han desarrollado jornadas de capacitación en Ciencia Abierta. Esta presentación esta asociada a las temáticas de Datos abiertos y planes de gestión de datos de modo de generar procesos que permitan la preservación, el cuidado y el resguardo de los datos de investigaciones.
description: Proyecto InES Ciencia Abierta - UFRO. financiado por la Agencia Nacional de Investigación y Desarrollo, Chile.
Adiabatic approximation for a uniform DC electric field
Creators: name: Siu, Zhuo Bin
name: Jalil, Mansoor B. A.
name: Tan, Seng Ghee
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: In this work, we show that the disorder-free Kubo formula for the non-equilibrium value of an observable due to a DC electric field, represented by $E_x\hat{x}$ in the Hamiltonian, can be interpreted as the standard time-independent theory response of the observable due to a time- and position-\textit{independent} perturbation $H_{MF}$. We derive the explicit expression for $H_{MF}$ and show that it originates from the adiabatic approximation to $\langle k|E_x\hat{x}$ in which transitions between the different eigenspinor states of a system are forbidden. The expression for $H_{MF}$ is generalized beyond the real spin degree of freedom to include other spin-like discrete degrees of freedom (e.g. valley and pseudospin). By direct comparison between Kubo formula and the time-independent perturbation theory, as well as the Sundaram-Niu wavepacket formalism, we show that $H_{MF}$ reproduces the effect of the E-field, i.e. $E_x\hat{x}$, up to the first order. This replacement suggests the emergence of a new spin current term that is not captured by the standard Kubo formula spin current calculation. We illustrate this via the exemplary spin current for the heavy hole spin 3/2 Luttinger system. Finally, we apply the formalism and derive an analogous $H_{MF}$ for the effects of a weakly position-dependent coupling to the spin-like internal degrees of freedom. This gives rise to an anomalous velocity as well as spin accumulation terms in spin$\otimes$pseudospin space in addition to those contained explicitly in the unperturbed Hamiltonian.
Keyframe-Based Visual-Inertial Online SLAM with Relocalization
Creators: name: Kasyanov, Anton
name: Engelmann, Francis
name: Stückler, Jörg
name: Leibe, Bastian
Publisher: name: arXiv
Year: 2017
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Complementing images with inertial measurements has become one of the most popular approaches to achieve highly accurate and robust real-time camera pose tracking. In this paper, we present a keyframe-based approach to visual-inertial simultaneous localization and mapping (SLAM) for monocular and stereo cameras. Our visual-inertial SLAM system is based on a real-time capable visual-inertial odometry method that provides locally consistent trajectory and map estimates. We achieve global consistency in the estimate through online loop-closing and non-linear optimization. Furthermore, our system supports relocalization in a map that has been previously obtained and allows for continued SLAM operation. We evaluate our approach in terms of accuracy, relocalization capability and run-time efficiency on public indoor benchmark datasets and on newly recorded outdoor sequences. We demonstrate state-of-the-art performance of our system compared to a visual-inertial odometry method and baseline visual SLAM approaches in recovering the trajectory of the camera.
Generating large misalignments in gapped and binary discs
Creators: name: Owen, James E.
name: Lai, Dong
Publisher: name: arXiv
Year: 2017
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Many protostellar gapped and binary discs show misalignments between their inner and outer discs; in some cases, $\sim70$ degree misalignments have been observed. Here we show that these misalignments can be generated through a "secular precession resonance" between the nodal precession of the inner disc and the precession of the gap-opening (stellar or massive planetary) companion. An evolving protostellar system may naturally cross this resonance during its lifetime due to disc dissipation and/or companion migration. If resonance crossing occurs on the right timescale, of order a few Myrs, characteristic for young protostellar systems, the inner and outer discs can become highly misaligned ($\gtrsim 60$ degrees). When the primary star has a mass of order a solar mass, generating a significant misalignment typically requires the companion to have a mass of $\sim 0.01-0.1$ M$_\odot$ and an orbital separation of tens of AU. The recently observed companion in the cavity of the gapped, highly misaligned system HD 142527 satisfies these requirements, indicating that a previous resonance crossing event misaligned the inner and outer discs. Our scenario for HD 142527's misaligned discs predicts that the companion's orbital plane is aligned with the outer disc's; this prediction should be testable with future observations as the companion's orbit is mapped out. Misalignments observed in several other gapped disc systems could be generated by the same secular resonance mechanism.
description: 12 pages, 8 figures, submitted to MNRAS
Note on the ideal frame formulation
Creators: name: Lara, Martin
Publisher: name: arXiv
Year: 2016
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics

description: An implementation of the ideal frame formulation of perturbed Keplerian motion is presented which only requires the integration of a differential system of dimension 7, contrary to the 8 variables traditionally integrated with this approach. The new formulation is based on the integration of a scaled version of the Eulerian set of redundant parameters, and slightly improves runtime performance with respect to the 8 dimensional case while retaining comparable accuracy.
description: 17 pages; wrong citation (Broucke et al, 1971) removed from previous version
Networks for European, American, and African Research: NEAAR
Creators: name: Schopf, Jennifer M.
Publisher: name: UbuntuNet Alliance
Year: 2016
Subjects: NEAAR

description: The Networks for European, American, and African Research (NEAAR) collaboration is a powerful, cross organizational project that will provide services and bandwidth connecting researchers in Europe, Africa, and the United States. This project will have an immediate impact on the research environment and also supports future application and technology advances. Indiana University (IU) will jointly lead the NEAAR collaboration with GÉANT, the European research and education network (REN), in a cooperative partnership with the African regional RENs: the UbuntuNet Alliance, the Arab States Research and Education Network (ASREN), the West and Central African Research and Education Network (WACREN), as well as the South African National Research Network (SANReN) and the Tertiary Education and Research Network of South Africa (TENET). Through its extensive regional partnerships, NEAAR has the potential to reach R&E communities in over 80 countries across three continents. NEAAR has the potential to be transformational to scientific research by providing not only the network but also the human expertise to make the most of international collaborations and data sharing, thereby increasing research and educational opportunities. Through additional capacity to Europe and targeted support of data and networking support services in Africa, NEAAR will be able to support a wide variety of research sharing between Africa and the US. Advanced data sharing fundamentally changes and extends the research that is feasible between partners, and NEAAR has the potential to have an unprecedented impact on US-Africa collaboration. This presentation will detail the NEAAR technological plans for network connections and data-enhanced exchange points. It will also describe the multi-faceted work that is being planned to engage end users to make better use of network connections across the region.
Mid-infrared characterization of the planetary-mass companion ROXs 42B b
Creators: name: Daemgen, Sebastian
name: Todorov, Kamen
name: Silva, Jasmin
name: Hand, Derek
name: Garcia, Eugenio V.
name: Currie, Thayne
name: Burrows, Adam
name: Stassun, Keivan G.
name: Ratzka, Thorsten
name: Debes, John H.
name: Lafreniere, David
name: Jayawardhana, Ray
name: Correia, Serge
Publisher: name: arXiv
Year: 2017
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We present new Keck/NIRC2 3$-$5 $μ$m infrared photometry of the planetary-mass companion to ROXS 42B in $L^\prime$, and for the first time in Brackett-$α$ (Br$α$) and in $M_\mathrm{s}$-band. We combine our data with existing near-infrared photometry and $K$-band (2$-$2.4 $μ$m) spectroscopy and compare these with models and other directly imaged planetary-mass objects using forward modeling and retrieval methods in order to characterize the atmosphere of ROXS 42B b. ROXS 42B b's 1.25$-$5 $μ$m spectral energy distribution most closely resembles that of GSC 06214 B and $κ$ And b, although it has a slightly bluer $K_{\rm s}$$-$$M_{\rm s}$ color than GSC 06214 B and thus so far lacks evidence for a circumplanetary disk. We cannot formally exclude the possibility that any of the tested dust-free/dusty/cloudy forward models describe atmosphere of ROXS 42B b well. However, models with substantial atmospheric dust/clouds yield temperatures and gravities that are consistent when fit to photometry and spectra separately, whereas dust-free model fits to photometry predict temperatures/gravities inconsistent with ROXS 42B b's $K$-band spectrum and vice-versa. Atmospheric retrieval on the 1$-$5 $μ$m photometry places a limit on the fractional number density of CO$_2$ of $\log(n_{\rm CO_2})
description: 11 pages, 8 figures. Accepted for publication in Astronomy & Astrophysics