cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Surface layer dynamics and a study of finestructure in Knight Inlet, British Columbia
Creators: name: Van Der Baaren, Augustine
Publisher: name: University of British Columbia
Year: 2010

description: In the first part of this thesis I investigated the surface layer dynamics of Knight Inlet to see which of the governing forces: inertial accelerations, pressure gradient, or stress, dominated the momentum balance for a steady two-layer flow. I estimated the inertial terms and pressure term in the momentum equation, which had been integrated over the surface layer, from conductivity, temperature, and depth data measured in Knight Inlet in the springs of 1986 and 1987. I solved for the coefficient of interfacial friction, k, so that an estimate of the interfacial stress, Tί = pkΔu², could be made. I obtained the idea of the Knight Inlet analysis from an earlier attempt I had made at resolving the balance of forces in the Fraser River plume. I found an estimate of the friction coefficient at the interface for the plume; k = 1.55 x 10¯⁴, which was much smaller than an assumed value used by Cordes, et al. (1980). The results of the Knight Inlet study showed that within the inlet (inside the sill), the pressure gradient, and the stress dominated the balance for high runoff conditions. Estimates of the coefficient of friction were on the order of 10⁻² and 10⁻³. The depth of the interface appeared to be constant inland of the sill. The second part of this thesis was a qualitative study of fine structure in Knight Inlet. I processed the CTD data measured in 1986 and 1987 to find the first differences of temperature and salinity. I used the profiles of ΔT and ΔS to describe features present in the upper and lower water. Later, data that had been measured with a special microprofiler at the same time as the 1987 CTD data were sampled, were compared to the CTD data. For this comparison, I studied profiles of [formula omitted] (calculated as a centered first difference), and the log of the variance of [formula omitted]. Results of this study were that the upper water (< 30 m) appeared more highly active than the deeper water (> 30 m), especially at the head of the inlet, at the sill, and in the region of the interface. The deeper water contained fluctuations of temperature and salinity that were concentrated in patches which were several meters thick. For the year, 1987, the microprofiler revealed the existence of temperature variations that were more significant than I had originally judged from the profiles of ΔT and ΔS. Values of the variance of the temperature gradient, [formula omitted] in some areas of the deeper water were almost as large as values in the upper water.
Phylogeny of terraranan frogs based on 2,665 loci and impacts of missing data on phylogenomic analyses
Creators: name: Barrientos, Lucas S.
name: Streicher, Jeffrey W.
name: Miller, Elizabeth C.
name: Pie, Marcio R.
name: Wiens, John J.
name: Crawford, Andrew J.
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Evolutionary Biology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: Ecology
subject: 69999 Biological Sciences not elsewhere classified

description: Terraranae is a large clade of New World direct-developing frogs that includes 3–5 families and >1,100 described species (∼15% of all named frog species). The relationships among major groups of terraranan frogs have been highly contentious, including conflicts among four recent phylogenomic studies utilizing 95, 220, 389, and 2,214 nuclear loci, respectively. In this paper, we re-evaluate relationships within Terraranae using a novel genomic dataset for 16 ingroup species representing most terraranan families and subfamilies. The preferred data matrix consisted of 2,665 nuclear loci from ultraconserved elements (UCEs), with a total of 743,419 aligned base pairs and 57% missing data. Concatenated likelihood analyses and coalescent-based species-tree analyses recovered strong statistical support for the following relationships among terraranan families: (Brachycephalidae, (Eleutherodactylidae, (Craugastoridae + ‘Strabomantidae’))). This position for Brachycephalidae agrees with two previous phylogenomic studies but conflicts with two others. Our results infer Strabomantis (of the Strabomantidae) to be with (or within) Craugastor (Craugastoridae), rather than with other strabomantid genera. This renders Strabomantidae paraphyletic with respect to Craugastoridae. Our results also suggest that Pristimantinae is paraphyletic with respect to Holoadeninae. We also find that using matrices with less missing data (and concomitantly fewer UCE loci) generally resulted in trees with lower mean branch support and problematic phylogenies (e.g. non-monophyly of terraranans). Overall, our results help resolve controversial relationships within one of the largest clades of frogs, with a dataset including ∼7 times more loci than those used in previous studies focused on this clade.
From Solitary Pro-Sumers to Energy Community: Quantitative Assesment of the Benefits of Sharing Electricity
Creators: name: Lovati, M.
name: Adami, J.
name: Dallapiccola, M.
name: Barchi, G.
name: Maturi, L.
name: Moser, D.
Publisher: name: WIP
Year: 2019
Subjects: PV Applications and Integration
PV Driven Energy Management and System Integration

description: 36th European Photovoltaic Solar Energy Conference and Exhibition; 1696-1701
description: The use of urban photovoltaic systems for the generation of on-site electricity in residential application was known primary for single households in the past. Today a proliferation of emerging technologies in disparate fields of research and industry promise to shift urban photovoltaics from single prosumers to integrated pro-sumer communities. These comprise, mini grids, smart meters, district scale storage and block-chain markets which are gaining significant momentum. This study shows the quantitative advantage of a shared vs. a solitary cost-optimal system in terms of installed capacity, economic benefit, self-sufficiency rate and LCOE (Levelized Cost of Electricity). The study has been conducted on 16 single family houses characterized by their geometry and their hourly electricity demands, a techno-economic optimization of capacity and positions of photovoltaic system and capacity of storage was performed with two different reward functions: to maximize the NPV (Net Present Value) and minimize LCOE while guaranteeing 27% of selfsufficiency. The same optimization procedure was performed on each home separately and on different sets of homes aggregated, the comparison of the results is shown and discussed.
Phase-Covariant Quantum Benchmarks
Creators: name: Calsamiglia, J.
name: Aspachs, M.
name: Munoz-Tapia, R.
name: Bagan, E.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We give a quantum benchmark for teleportation and quantum storage experiments suited for pure and mixed test states. The benchmark is based on the average fidelity over a family of phase-covariant states and certifies that an experiment can not be emulated by a classical setup, i.e., by a measure-and-prepare scheme. We give an analytical solution for qubits, which shows important differences with standard state estimation approach, and compute the value of the benchmark for coherent and squeezed states, both pure and mixed.
description: 4 pages, 2 figures
Impact of the laser spatio-temporal shape on Breit-Wheeler pair production
Creators: name: Mercuri-Baron, A.
name: Grech, M.
name: Niel, F.
name: Grassi, A.
name: Lobet, M.
name: Di Piazza, A.
name: Riconda, C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: The forthcoming generation of multi-petawatt lasers opens the way to abundant pair production by the nonlinear Breit-Wheeler process, i.e., the decay of a photon into an electron-positron pair inside an intense laser field. In this paper we explore the optimal conditions for Breit-Wheeler pair production in the head-on collision of a laser pulse with gamma photons. The role of the laser peak intensity versus the focal spot size and shape is examined keeping a constant laser energy to match experimental constraints. A simple model for the soft-shower case, where most pairs originate from the decay of the initial gamma photons, is derived. This approach provides us with a semi-analytical model for more complex situations involving either Gaussian or Laguerre-Gauss (LG) laser beams. We then explore the influence of the order of the LG beams on pair creation. Finally we obtain the result that, above a given threshold, a larger spot size (or a higher order in the case of LG laser beams) is more favorable than a higher peak intensity. Our results match very well with three-dimensional particle-in-cell simulations and can be used to guide upcoming experimental campaigns.
description: 34 pages, 11 figures, submitted to New J. Phys
Hundreds of new DNA barcodes for South African sponges
Creators: name: Ngwakum, Benedicta B.
name: Payne, Robyn P.
name: Teske, Peter R.
name: Janson, Liesl
name: Kerwath, Sven E.
name: Samaai, Toufiek
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Biochemistry
subject: Molecular Biology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: Marine Biology
subject: Inorganic Chemistry

description: DNA barcoding based on a fragment of the cytochrome c oxidase subunit I (COI) gene from the mitochondrial genome is widely applied in species identification, species discovery and biodiversity studies. The aim of this study was to establish a barcoding reference database of sponges collected from South Africa, and evaluate the applicability of the COI gene for aiding in the identification of sponges in combination with tentative morphological identifications. A total of 317 mitochondrial COI barcode sequences, with an additional 21 extended COI fragments and 24 nuclear ITS sequences, were obtained from 11 orders, 38 families, 58 genera and 124 species of spiculated sponges. A Neighbour Joining (NJ) trees that were reconstructed using these sequences in most cases clustered species in accordance with their current taxonomic identification, and we conclude that COI sequencing can be used to aid in the identification of sponge species. We further demonstrate that DNA barcoding analysis has potential to uncover cryptic sponge species, and to reveal dubious morphological identifications. We recommend that future taxonomic studies of South African sponges incorporate multiple sources of information for species identification or discovery.
Coefficient of tangential restitution for the linear dashpot model
Creators: name: Becker, Volker
name: Schwager, Thomas
name: Poeschel, Thorsten
Publisher: name: arXiv
Year: 2007
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The linear dashpot model for the inelastic normal force between colliding spheres leads to a constant coefficient of normal restitution, $ε_n=$const., which makes this model very popular for the investigation of dilute and moderately dense granular systems. For two frequently used models for the tangential interaction force we determine the coefficient of tangential restitution $ε_t$, both analytically and by numerical integration of Newton's equation. Although $ε_n=$const. for the linear-dashpot model, we obtain pronounced and characteristic dependencies of the tangential coefficient on the impact velocity $ε_t=ε_t(\vec{g})$. The results may be used for event-driven simulations of granular systems of frictional particles.
description: 12 pages, 12 figures
Self-Assemble-Featured Internet of Things
Creators: name: Lemoine, Frédéric
name: Aubonnet, Tatiana
name: Simoni, Noëmie
Publisher: name: arXiv
Year: 2021
Subjects: subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: The Internet of Things supports various industrial applications. The cooperation and coordination of smart things are a promising strategy for satisfying requirements that are beyond the capacity of a single smart thing. One of the major challenges for today's software engineering is the management of large and complex computing systems characterized by a high degree of physical distribution. Examples of such systems arise in many application domains. The number of connected devices grows from billions to hundreds of billions, so a maximum of automatisms must be integrated in IoT architectures in order to control and manage them. Software architects migrate to service oriented architecture and applications are now being constructed as service compositions. Since each IoT device includes one or more microservices, the increasing number of devices around the user makes them difficult to assemble in order to achieve a common goal. In this paper, we propose a self-assembling solution based on self-controlled service components taking into account non-functional requirements concerning the offered quality of services and the structuration of the resulting assembly. Its aim is to build and maintain an assembly of services (taking into account arrival of new peers or failure of existing ones) that, besides functional requirements, also fulfils global quality-of-service and structural requirements.
description: 21 pages, 16 figures
Spreading of a granular droplet
Creators: name: Sanchez, Ivan
name: Raynaud, Franck
name: Lanuza, Jose
name: Andreotti, Bruno
name: Clement, Eric
name: Aranson, Igor S.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: The influence of controlled vibrations on the granular rheology is investigated in a specifically designed experiment. We study experimentally a thin granular film spreading under the action of horizontal vibrations. A nonlinear diffusion equation is derived theoretically that describes the evolution of the deposit shape. A self-similar parabolic shape (the``granular droplet'') and a spreading dynamics are predicted that both agree quantitatively with the experimental results. The theoretical analysis is used to extract effective dynamic friction coefficients between the base and the granular layer under sustained and controlled vibrations. We derive an empirical friction law involving external driving parameters and the layer height to represent our data.
description: 4 pages, 3 figures
Fast Mesh Validation in Combustion Simulations through In-Situ Visualization
Creators: name: Shudler, Sergei
name: Ferrier, Nicola
name: Insley, Joseph
name: Papka, Michael E.
name: Patel, Saumil
name: Rizzi, Silvio
Publisher: name: The Eurographics Association
Year: 2019
Subjects: Human
centered computing
Visualization systems and tools
Computing methodologies
Massively parallel and high
performance simulations
General and reference
Performance

description: In-situ visualization and analysis is a powerful concept that aims to give users the ability to process data while it is still resident in memory, thereby vastly reducing the amount of data left for post-hoc analysis. The problem of having too much data for posthoc analysis is exacerbated in large-scale high-performance computing applications such as Nek5000, a massively-parallel CFD (Computational Fluid Dynamics) code used primarily for thermal hydraulics problems. Specifically, one problem users of Nek5000 often face is validating the mesh, that is identifying the exact location of problematic mesh elements within the whole mesh. Employing the standard post-hoc approach to address this problem is both time consuming and requires vast storage space. In this paper, we demonstrate how in-situ visualization, produced with SENSEI, a generic in-situ platform, helps users quickly validate the mesh. We also provide a bridge between Nek5000 and SENSEI that enables users to use any existing and future analysis routines in SENSEI. The approach is evaluated on a number of realistic datasets.
description: Eurographics Symposium on Parallel Graphics and Visualization
description: Session 1
description: 7
description: 16
description: Sergei Shudler, Nicola Ferrier, Joseph Insley, Michael E. Papka, Saumil Patel, and Silvio Rizzi
description: CCS Concepts: Human-centered computing --> Visualization systems and tools;  Computing methodologies --> Massively parallel and high-performance simulations;  General and reference --> Performance
On quark masses in holographic QCD
Creators: name: McNees, Robert
name: Myers, Robert C.
name: Sinha, Aninda
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Recently certain nonlocal operators were proposed to provide quark masses for the holographic model of QCD developed by Sakai and Sugimoto. The properties of these operators at strong coupling are examined in detail using holographic techniques. We find the renormalization procedure for these operators is modified by the running of the five-dimensional gauge coupling. We explicitly evaluate the chiral condensate characterized by these operators.
description: 31+1 pages, 8 figures
Static dipole polarizabilities of polyacenes using self-interaction-corrected density functional approximations
Creators: name: Akter, Sharmin
name: Yamamoto, Yoh
name: Zope, Rajendra R.
name: Baruah, Tunna
Publisher: name: arXiv
Year: 2021
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Density functional approximations are known to significantly overestimate the polarizabilities of long chain-like molecules. We study the static electric dipole polarizabilities and the vertical ionization potentials of polyacenes from benzene to pentacene using the Fermi-Löwdin orbital based self-interaction corrected (FLOSIC) density functional method. The orbital-by-orbital self-interaction correction corrects for the overestimation tendency of density functional approximations. The polarizabilities calculated with FLOSIC-DFA are however overly corrected. We also tested the recently developed locally-scaled self-interaction correction (LSIC) method on the polyacenes. The local-scaling method applies full SIC in the one-electron regions and restores the proper behavior of the SIC exchange-correlation functionals in the uniform density limit. The results show that LSIC removes the overcorrection tendency of the FLOSIC-DFA and produces results that are in excellent agreement with reference CCSD values. The vertical ionization potentials with LSIC also show good agreement with available experimental values.
description: 17 pages, 4 figures, 2 tables
Decay dynamics of Localised Surface Plasmons: damping of coherences and populations of the oscillatory plasmon modes
Creators: name: Kolwas, Krystyna
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Properties of plasmonic materials are associated with surface plasmons - the electromagnetic excitations coupled to coherent electron charge density oscillations on a metal/dielectric interface. Although decay of such oscillations cannot be avoided, there are prospects for controlling plasmon damping dynamics. In spherical metal nanoparticles (MNPs) the basic properties of Localized Surface Plasmons (LSPs) can be controlled with their radius. The present paper handles the link between the size-dependent description of LSP properties derived from the dispersion relation based on Maxwell's equations and the quantum picture in which MNPs are treated as "quasi-particles". Such picture, based on the reduced density-matrix of quantum open systems ruled by the master equation in the Lindblad form, enables to distinguish between damping processes of populations and coherences of multipolar plasmon oscillatory states and to establish the intrinsic relations between the rates of these processes, independently of the size of MNP. The impact of the radiative and the nonradiative energy dissipation channels is discussed.
|Vub| from exclusive semileptonic B to pi decays revisited
Creators: name: Flynn, Jonathan M
name: Nieves, Juan
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We update the extraction of |Vub| from exclusive semileptonic B to pi decays, combining experimental partial branching fraction information with theoretical form factor calculations, using the recently revised HPQCD results for the form factors f_+ and f_0. We use Omnes representations to provide the required parametrisations of the form factors. The extracted value is 10^3 |Vub| = 3.47+/-0.29+/-0.03, in striking agreement with |Vub| extracted using all other inputs in CKM fits and showing some disagreement with |Vub| extracted from inclusive semileptonic B to pi decays.
description: 5 pages, 1 figure. Version accepted for publication
Scalable Parallel Flow Visualization Using 3D Line Integral Convolution for Large Scale Unstructured Simulation Data
Creators: name: Liao, Yangguang
name: Matsui, Hiroaki
name: Kreylos, Oliver
name: Kellogg, Louise H.
Publisher: name: The Eurographics Association
Year: 2019
Subjects: Human
centered computing
Scientific visualization
Software and its engineering
Parallel programming languages
Computing methodologies
Concurrent algorithms

description: To address the need of highly efficient and scalable parallel flow visualization methods, we developed a flow visualization system for large unstructured simulation data using parallel 3D line integral convolution (LIC). The main consideration for a parallel LIC implementation is a trade-off between the additional memory cost of replicating cells at sub-domain boundaries, or the communication cost of exchanging those data among computation nodes. To improve scalability, we introduce a load-balancing scheme that partitions datasets based on estimated LIC computation time. We also introduce a data-driven sub-domain extension scheme that determines which external cells at sub-domain boundary need to be added based on current boundary cells, which reduces memory overhead because the same visual quality can be achieved with a significantly smaller number of replicated external cells. We evaluate our visualization method by first comparing its parallel scalability to traditional integral field lines methods. Next, we compare our cost-driven domain decomposition method to existing methods to verify that ours leads to more balanced computation and improved scalability. Finally, we compare our data-driven sub-domain expansion method to traditional layer-based expansion methods in terms of memory overhead and visual quality. We conclude that our parallel 3D LIC method is an efficient and scalable approach to visualization of large and complex 3D vector fields.
description: Eurographics Symposium on Parallel Graphics and Visualization
description: Session 1
description: 17
description: 25
description: Yangguang Liao, Hiroaki Matsui, Oliver Kreylos, and Louise H. Kellogg
description: CCS Concepts: Human-centered computing --> Scientific visualization;  Software and its engineering --> Parallel programming languages;  Computing methodologies --> Concurrent algorithms
Low energy scattering with a nontrivial pion
Creators: name: Fariborz, Amir H.
name: Jora, Renata
name: Schechter, Joseph
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: An earlier calculation in a generalized linear sigma model showed that the well-known current algebra formula for low energy pion pion scattering held even though the massless Nambu Goldstone pion contained a small admixture of a two-quark two-antiquark field. Here we turn on the pion mass and note that the current algebra formula no longer holds exactly. We discuss this small deviation and also study the effects of an SU(3) symmetric quark mass type term on the masses and mixings of the eight SU(3) multiplets in the model. We calculate the s wave scattering lengths, including the beyond current algebra theorem corrections due to the scalar mesons, and observe that the model can fit the data well. In the process, we uncover the way in which linear sigma models give controlled corrections (due to the presence of scalar mesons) to the current algebra scattering formula. Such a feature is commonly thought to exist only in the non-linear sigma model approach.
description: 15 pages, 8 figures
Ventral Tegmental Area Dopamine Neurons Flexibly Code Taste Valence in Conditioned Taste Aversion
Creators: name: Hurh, Samantha J.
Publisher: name: University of Illinois at Chicago
Year: 2024

description: Our behaviors are constantly shaped by both internal and external environments to optimize favorable outcomes and protect ourselves from potential harm. Our experiences heavily influence these adaptations, which serve as driving forces, allowing us to integrate information and form associations between stimuli and their consequences. Associative learning, therefore, plays a crucial role in driving goal-directed behavior. The mesolimbic-dopamine pathway is well-established as critical in motivating behaviors, such as approach and avoidance. Rewards and their predictors have been shown to reliably evoke increases in dopamine signaling. However, the extent to which mesolimbic dopamine codes a stimulus's valence or salience to further promote goal-directed behaviors remains a subject of debate. To address this debate, I examined whether ventral tegmental area (VTA) dopamine neurons code the change in the valence of the same taste before and after a conditioned taste aversion (CTA) paradigm. Here, in all experiments, naïve rats received brief intra-oral infusions of sucrose and, immediately after, were randomly assigned to injection conditions: 20ml/kg 0.15M NaCl (Unpaired) or equal volume 0.15M LiCl (Paired) to induce malaise and form a CTA. CTA expression was measured in later sessions of brief intra-oral infusions of sucrose, where VTA dopamine responses were measured using in vivo fiber photometry. Concurrently, the rats' behavioral reactions during intra-oral infusions and avoidance of the conditioned taste were measured in separate experiments. I found dopamine initially responds with increases to sucrose but is suppressed after a single sucrose-LiCl pairing. Behavioral reactivity data supported more movement in response to sucrose after CTA – suggesting that a decrease in dopamine to sucrose in Paired rats was not due to a loss of stimulus salience. My overall findings support 1) that VTA dopamine neurons code changes in taste valence, as opposed to salience, based on post-ingestion experiences, 2) that VTA dopamine neurons track changes in taste valence in CTA extinction, 3) that changes in VTA dopamine responses are experience-dependents and correlate with avoidance behavior, 4) that changes in VTA dopamine responses are unaffected by a minimal dose of LiCl, and 5) that VTA dopamine responses scale with multiple conditioning and extinction trials.
Task-based Augmented Reeb Graphs with Dynamic ST-Trees
Creators: name: Gueunet, Charles
name: Fortin, Pierre
name: Jomier, Julien
name: Tierny, Julien
Publisher: name: The Eurographics Association
Year: 2019

description: This paper presents, to the best of our knowledge, the first parallel algorithm for the computation of the augmented Reeb graph of piecewise linear scalar data. Such augmented Reeb graphs have a wide range of applications, including contour seeding and feature based segmentation. Our approach targets shared-memory multi-core workstations. For this, it completely revisits the optimal, but sequential, Reeb graph algorithm, which is capable of handing data in arbitrary dimension and with optimal time complexity. We take advantage of Fibonacci heaps to exploit the ST-Tree data structure through independent local propagations, while maintaining the optimal, linearithmic time complexity of the sequential reference algorithm. These independent propagations can be expressed using OpenMP tasks, hence benefiting in parallel from the dynamic load balancing of the task runtime while enabling us to increase the parallelism degree thanks to a dual sweep. We present performance results on triangulated surfaces and tetrahedral meshes. We provide comparisons to related work and show that our new algorithm results in superior time performance in practice, both in sequential and in parallel. An open-source C++ implementation is provided for reproducibility.
description: Eurographics Symposium on Parallel Graphics and Visualization
description: Session 1
description: 27
description: 37
description: Charles Gueunet, Pierre Fortin, Julien Jomier, and Julien Tierny
AUTENTICAÇÃO DE DIPLOMAS DO ENSINO SUPERIOR BASEADO NO CONCEITO DE REGISTRO IMUTÁVEL FUNDAMENTADO EM BLOCKCHAIN
Creators: name: Pinho, Adnan Dos Santos De
name: Neto, Francisco Jose Badaro Valente
Publisher: name: Zenodo
Year: 2019
Subjects: Blockhain
Hyperledger Fabric
Smart-contract
Autenticação de Diplomas

description: Com o atual crescimento da tecnologia, cresce também as maneiras de falsificação de objetos, softwares, notas, documento, informações, dados e etc. Com o intuito de encurtar o caminho em prol da carreira profissional, várias pessoas tendem a falsificar diplomas, a fim de obter vantagem entre os outros participantes apoiados na ausência de um mecanismo comum de validação dos diplomas emitidos pelas instituições de ensino superior. As tecnologias de Blockchain se apresentam como uma possibilidade promissora para o desenvolvimento de método de validação e armazenamento de registros de forma segura, imutável. Compondo assim o cenário ideal para o registro e controle de dados e informações, mecanismo fundamental para a definição de um processo que busque a validação e armazenamento seguro de documentos, notas e dados, inclusive os importantes diplomas, documentos de importância social. Dificultando assim o processo de falsificação deste importante documento social. O objetivo deste trabalho é, sobre a necessidade notória de uma solução para a validação de diplomas, e em linha com as demandas do ministério da educação do Brasil especificadas na portaria 330 de 05 de abril de 2018, efetuar um comparativo das tecnologias de blockchain existentes, identificar as necessidades tecnológicas para a implementação da Hyperledger Fabric, propor e publicar uma solução de autenticação de diplomas baseado no conceito de registro imutável utilizando a blockchain Hyperledger Fabric. Uma blockchain privada, que tem como administradora a Linux Foundation. De acordo com a sua finalidade, a pesquisa realizada neste trabalho é classificada como uma pesquisa aplicada com produção de protótipo, tendo como protótipo uma aplicação Web e Mobile capaz de publicar e consultar a autenticidade de diplomas através da blockchain Hyperledger, protótipo este que será publicado completamente na internet de forma que todas as instituições de ensino superior interessadas em implementar, o façam, contribuindo assim com a erradicação deste problema social que é a falsificação de diplomas principalmente no ensino superior.
Short-term interaction between nitrate and ammonium uptake for cells of a marine diatom grown under different degrees of light limitation
Creators: name: Yin, Kedong
Publisher: name: University of British Columbia
Year: 2010

description: The short-term interaction between nitrate and ammonium uptake was examined for a marine diatom, Thalassiosira pseudonana, grown in the continuous turbidostat cultures under different degrees of light limitation. Nitrate uptake in the absence and in the presence of ammonium and ammonium uptake in the absence and in the presence of nitrate were measured during a 6 min time course after a solution of both nitrate and ammonium was passed across the cells trapped on the filter. It was found that the interaction between nitrate and ammonium uptake occurred immediately and continued for the remainder of the time course. The effect of light on the interaction was apparent. In the less light-limited cultures, nitrate uptake was depressed by ammonium. In contrast, in the most light-limited culture, the depression of nitrate uptake by ammonium disappeared. Ammonium uptake was dependent on the degree of light limitation of the cultures. For all the cultures, ammonium uptake was initially enhanced and then declined with time. However, only the initial (1 min) enhanced uptake of ammonium was suppressed by the presence of nitrate, and the subsequent ammonium uptake rate was unaffected. Possible explanations and the ecological significance of the interaction are discussed.
k-defects as compactons
Creators: name: Adam, C.
name: Sanchez-Guillen, J.
name: Wereszczynski, A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We argue that topological compactons (solitons with compact support) may be quite common objects if $k$-fields, i.e., fields with nonstandard kinetic term, are considered, by showing that even for models with well-behaved potentials the unusual kinetic part may lead to a power-like approach to the vacuum, which is a typical signal for the existence of compactons. The related approximate scaling symmetry as well as the existence of self-similar solutions are also discussed. As an example, we discuss domain walls in a potential Skyrme model with an additional quartic term, which is just the standard quadratic term to the power two. We show that in the critical case, when the quadratic term is neglected, we get the so-called quartic $ϕ^4$ model, and the corresponding topological defect becomes a compacton. Similarly, the quartic sine-Gordon compacton is also derived. Finally, we establish the existence of topological half-compactons and study their properties.
description: the stability proof of Section 4.4 corrected, some references added
Non-local effects in the shear banding of a thixotropic yield stress fluid
Creators: name: Serial, Raquel
name: Bonn, Daniel
name: Huppertz, Thom
name: Dijksman, Joshua A.
name: van der Gucht, Jasper
name: van Duynhoven, John P. M.
name: Terenzi, Camilla
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We observe a novel type of shear banding in the rheology of thixotropic yield-stress fluids that is due to the coupling of both non-locality and thixotropy. The latter is known to lead to shear banding even in homogeneous stress fields, but the bands observed in the presence of non-local effects appear different as the shear rate varies continuously over the shear band. Here, we introduce a simple non-local model for the shear banding (NL-SB), and we implement it for the analysis of micron-scale rheo-MRI velocimetry measurements of a milk microgel suspension in a cone-and-plate geometry. The proposed NL-SB model accurately quantifies the cooperativity length and yields values in the order of the aggregate size in the microgel.
Parallel XPBD Simulation of Modified Morse Potential - an Alternative Spring Model
Creators: name: Cetinaslan, Ozan
Publisher: name: The Eurographics Association
Year: 2019
Subjects: Computing methodologies
Physical simulation

description: In this paper, we introduce a modified Morse potential as an alternative to the existing spring models within a massively parallel extended Position Based Dynamics (XPBD) algorithm. To date, stretching is one of the most popular constraint types of XPBD frameworks due to its simplicity, robustness and efficiency. However, the underneath mathematical expression of stretching constraint does not fully represent a spring model and behaves too stiff over a certain iteration count or damping coefficient. On the other hand, Hookean spring potential behaves softer and viscoelastic within the XPBD algorithm under the same conditions as stretching constraint. Our modified Morse potential addresses this issue by keeping the simulation of deformable models in between Hooke's law and stretching constraint. To demonstrate the benefits of modified Morse potential with higher frame rates, we develop an efficient Independent Edge Grouping algorithm for XPBD method which provides parallel processing on GPU. We compare the simulation results of cloth and volumetric models with stretching constraint, Hookean and St. Venant-Kirchhoff (STVK) spring potentials. We believe that our modified Morse potential is easy to implement and seamlessly fit into the existing XPBD frameworks.
description: Eurographics Symposium on Parallel Graphics and Visualization
description: Session 2
description: 39
description: 48
description: Ozan Cetinaslan
description: CCS Concepts: Computing methodologies --> Physical simulation
Nonlinear dynamics of hydrodynamic tori as a model of oscillations and bending waves in astrophysical discs
Creators: name: Fairbairn, Callum W.
name: Ogilvie, Gordon I.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Understanding oscillations and waves in astrophysical fluid bodies helps to elucidate their observed variability and the underlying physical mechanisms. Indeed, global oscillations and bending modes of accretion discs or tori may be relevant to quasi-periodicity and warped structures around compact objects. While most studies rely on linear theory, observationally significant, nonlinear dynamics is still poorly understood, especially in Keplerian discs for which resonances typically demand a separate treatment. In this work we introduce a novel analytical model which exactly solves the ideal, compressible fluid equations for a non-self-gravitating elliptical cylinder within a local shearing sheet. The aspect ratio of the ring is an adjustable parameter, allowing a continuum of models ranging from a torus of circular cross-section to a thin ring. We restrict attention to flow fields which are a linear function of the coordinates, capturing the lowest order global motions and reducing the dynamics to a set of coupled ordinary differential equations (ODEs). This system acts as a framework for exploring a rich range of hydrodynamic phenomena in both the large amplitude and Keplerian regimes. We demonstrate the connection between tilting tori and warped discs within this model, showing that the linear modes of the ring correspond to oppositely precessing global bending modes. These are further confirmed within a numerical grid based simulation. Crucially, the ODE system developed here allows for a more tractable investigation of nonlinear dynamics. This will be demonstrated in a subsequent paper which evidences mode coupling between warping and vertical motions in thin tilted rings.
description: 14 pages, 7 figures, accepted version for publication in MNRAS
Quantum Sensor Miniaturization
Creators: name: Gilbert, G.
name: Hamrick, M.
name: Weinstein, Y. S.
name: Pappas, S. P.
name: Donadio, A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The classical bound on image resolution defined by the Rayleigh limit can be beaten by exploiting the properties of quantum mechanical entanglement. If entangled photons are used as signal states, the best possible resolution is instead given by the Heisenberg limit, an improvement proportional to the number of entangled photons in the signal. In this paper we present a novel application of entanglement by showing that the resolution obtained by an imaging system utilizing separable photons can be achieved by an imaging system making use of entangled photons, but with the advantage of a smaller aperture, thus resulting in a smaller and lighter system. This can be especially valuable in satellite imaging where weight and size play a vital role.
description: 3 pages, 1 figure. Accepted for publication in Photonics Technology Letters
Real-time Particle-based Snow Simulation on the GPU
Creators: name: Goswami, Prashant
name: Markowicz, Christian
name: Hassan, Ali
Publisher: name: The Eurographics Association
Year: 2019
Subjects: I.3.3 [Computer Graphics]
Animation
Physical simulation

description: This paper presents a novel real-time particle-based method for simulating snow on the GPU. Our method captures compression and bonding between snow particles, and incorporates the thermodynamics to model the realistic behavior of snow. The presented technique is computationally inexpensive, and is capable of supporting rendering in addition to physics simulation at high frame rates. The method is completely parallel and is implemented using CUDA. High efficiency and its simplicity makes our method an ideal candidate for integration in existing game SDK frameworks.
description: Eurographics Symposium on Parallel Graphics and Visualization
description: Session 2
description: 49
description: 57
description: Prashant Goswami, Christian Markowicz, and Ali Hassan
description: Categories and Subject Descriptors (according to ACM CCS): I.3.3 [Computer Graphics]: Animation-Physical simulation
La libert� accademica e il diritto di messa a disposizione del pubblico in Open Access = Academic Freedom and Right of Making Available in Open Access to the Public
Creators: name: Caso, Roberto
Publisher: name: Universit� degli studi di Trento. Facolt� di Giurisprudenza
Year: 2019

description: Some European Union Member States have since 2013 enacted legislation to give authors the inalienable and unavailable right of making their sci-entific works available in Open Access to the public. Works that represent the result of research financed with public funds although previously pub-lished by commercial publishers. A recent Italian legislative proposal moves in the same direction. The right to make scientific work available in Open Access to the public is an important shield of academic freedom. The topic is worth considering with the aim to discuss existing legislative models, the proposed Italian law and possible future developments.
The life cycle of magnetars: a novel approach to estimate their ages
Creators: name: Mondal, Tushar
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Anomalous X-ray pulsars and soft gamma repeaters are slowly rotating, young, and isolated neutron stars exhibiting sporadic outbursts and high X-ray quiescent luminosities. They are believed to be powered by ultrastrong magnetic fields, $B\sim10^{14}-10^{15}$ G, associated with `magnetars'. In the peculiar case of SGR 0418+5729, timing parameters imply a dipolar $B$-field of $6.1\times10^{12}$ G. This discovery has challenged the traditional picture of magnetars in terms of $B$-field strengths, evolutionary stages, and ages. Here we provide a novel approach to estimate a magnetar's age by considering the self-consistent time evolution of a plasma-filled oblique pulsar with the state-of-the-art magnetospheric particle acceleration gaps. The rotational period of magnetars increases over time due to angular momentum extraction by gravitational-wave radiations, magnetic dipole radiations, and particle winds. These torques also change the obliquity angle between the magnetic and rotation axes. For SGR 0418+5729, we obtain a dipolar $B$-field of $1.0\times10^{14}$ G, and a realistic age of $\sim18$ kyr, consistent within the magnetar paradigm.
description: 8 pages, 3 figures. Accepted for publication in ApJ Letters
Effect of Solder Configurations on Finger Breakages in Photovoltaic Modules under Thermal Cycling Conditions
Creators: name: Kumar, S.
name: Roy, S.
name: Gupta, R.
Publisher: name: WIP
Year: 2019
Subjects: Photovoltaic Modules and BoS Components
PV Module Design, Manufacture, Performance and Reliability

description: 36th European Photovoltaic Solar Energy Conference and Exhibition; 926-929
description: Finger breakages are frequently observed in crystalline silicon photovoltaic modules under thermal cycling (TC) stress conditions. The close proximity of the solder layer to fingers can make them vulnerable to inconsistencies in the solder configuration. This paper investigates the effect of different solder configurations on formation of finger breakages under TC test conditions. The experimental findings have been supported with thermomechanical damage simulated at the finger-solder interface using a 3-D finite element model of a photovoltaic module. The study identified various faulty solder configurations and investigated the correspondingly obtained finger breakages and simulated damage accumulation under TC test conditions. It was found that an adequate amount of solder thickness is crucial to maintain the thermo-mechanical reliability of fingers and avoid finger breakages. The presence of extra solder material was observed to catalyse finger breakages. Further, the case of dislocated ribbon configuration was demonstrated to be a key cause of finger breakages, which was supported with higher simulated damage in comparison to normal configuration. The findings from the investigation highlight the need to take precautionary measures during the soldering process of module manufacturing for enhanced finger reliability, which is essential for the overall PV module performance.
Hybrid Online Autotuning for Parallel Ray Tracing
Creators: name: Herveau, Killian
name: Pfaffe, Philip
name: Tillmann, Martin Peter
name: Tichy, Walter F.
name: Dachsbacher, Carsten
Publisher: name: The Eurographics Association
Year: 2019
Subjects: I.3.6 [Computer Graphics]
Methodology and Techniques
Graphics data structures and data types

description: Acceleration structures are key to high performance parallel ray tracing. Maximizing performance requires configuring the degrees of freedom (e.g., construction parameters) these data structures expose. Whether a parameter setting is optimal depends on the input (e.g., the scene and view parameters) and hardware. Manual selection is tedious, error prone, and is not portable. To automate the parameter selection task we use a hybrid of model-based prediction and online autotuning. The combination benefits from the best of both worlds: one-shot configuration selection when inputs are known or similar, effective exploration of the configuration space otherwise. Online tuning additionally serves to train the model on real inputs without requiring a-priori training samples. Online autotuning outperforms best-practice configurations recommended by the literature, by up to 11% median. The model predictions achieve 95% of the online autotuning performance while reducing 90% of the autotuner overhead. Hybrid online autotuning thus enables always-on tuning of parallel ray tracing.
description: Eurographics Symposium on Parallel Graphics and Visualization
description: Session 2
description: 59
description: 68
description: Killian Herveau, Philip Pfaffe, Martin Peter Tillmann, Walter F. Tichy, and Carsten Dachsbacher
description: Categories and Subject Descriptors (according to ACM CCS): I.3.6 [Computer Graphics]: Methodology and Techniques- Graphics data structures and data types