83 research outputs found

    Advanced Hough-based method for on-device document localization

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    The demand for on-device document recognition systems increases in conjunction with the emergence of more strict privacy and security requirements. In such systems, there is no data transfer from the end device to a third-party information processing servers. The response time is vital to the user experience of on-device document recognition. Combined with the unavailability of discrete GPUs, powerful CPUs, or a large RAM capacity on consumer-grade end devices such as smartphones, the time limitations put significant constraints on the computational complexity of the applied algorithms for on-device execution. In this work, we consider document location in an image without prior knowledge of the document content or its internal structure. In accordance with the published works, at least 5 systems offer solutions for on-device document location. All these systems use a location method which can be considered Hough-based. The precision of such systems seems to be lower than that of the state-of-the-art solutions which were not designed to account for the limited computational resources. We propose an advanced Hough-based method. In contrast with other approaches, it accounts for the geometric invariants of the central projection model and combines both edge and color features for document boundary detection. The proposed method allowed for the second best result for SmartDoc dataset in terms of precision, surpassed by U-net like neural network. When evaluated on a more challenging MIDV-500 dataset, the proposed algorithm guaranteed the best precision compared to published methods. Our method retained the applicability to on-device computations.Comment: This is a preprint of the article submitted for publication in the journal "Computer Optics

    Unfolder: Fast localization and image rectification of a document with a crease from folding in half

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    Presentation of folded documents is not an uncommon case in modern society. Digitizing such documents by capturing them with a smartphone camera can be tricky since a crease can divide the document contents into separate planes. To unfold the document, one could hold the edges potentially obscuring it in a captured image. While there are many geometrical rectification methods, they were usually developed for arbitrary bends and folds. We consider such algorithms and propose a novel approach Unfolder developed specifically for images of documents with a crease from folding in half. Unfolder is robust to projective distortions of the document image and does not fragment the image in the vicinity of a crease after rectification. A new Folded Document Images dataset was created to investigate the rectification accuracy of folded (2, 3, 4, and 8 folds) documents. The dataset includes 1600 images captured when document placed on a table and when held in hand. The Unfolder algorithm allowed for a recognition error rate of 0.33, which is better than the advanced neural network methods DocTr (0.44) and DewarpNet (0.57). The average runtime for Unfolder was only 0.25 s/image on an iPhone XR.Comment: This is a preprint of the article accepted for publication in the journal "Computer Optics

    Oxygen diffusion and surface exchange kinetics for the mixed-conducting oxide La0.6Sr0.4Co0.8Fe0.2O3–ή

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    Received: 14.11.2018. Accepted: 11.12.2018. Published: 31.12.2018.Studies of oxygen surface exchange kinetics for La0.6Sr0.4Co0.8Fe0.2O3–ή oxide were performed using the technique of isotopic exchange of molecular oxygen with analysis of gas phase isotopic composition in a static circulation system at the temperatures of 600–800 °С in the oxygen pressure range of 0.27–2.13 kPa. The values of interphase exchange rate and oxygen diffusion coefficient were determined. The effective activation energies for oxygen exchange and diffusion processes as well as the exponents in the dependence of these values versus oxygen pressure in the double logarithmic coordinates were calculated. The process of oxygen dissociative adsorption at the surface of La0.6Sr0.4Co0.8Fe0.2O3–ή oxide was found to be the rate-determining stage.This work is partly supported by the Russian Science Foundation (Project No. 17‑73‑10196) using facilities of shared access center “Composition of Compounds” of IHTE UB RAS

    Application of promising electrode materials in contact with a thin-layer ZrO2-based supporting electrolyte for solid oxide fuel cells

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    The paper presents the results of an investigation into thin single- and triple-layer ZrO2-Sc2O3-based electrolytes prepared using the tape-casting technique in combination with promising electrodes based on La2NiO4+ÎŽ and Ni-Ce0.8Sm0.2O2-ÎŽ materials. It is shown that pressing and joint sintering of single electrolyte layers allows multilayer structures to be obtained that are free of defects at the layer interface. Electrical conductivity measurements of a triple-layer electrolyte carried out in longitudinal and transverse directions with both direct and alternating current showed resistance of the interface between the layers on the total resistance of the electrolyte to be minimal. Long-term tests have shown that the greatest degradation in resistance over time occurs in the case of an electrolyte with a tetragonal structure. Symmetrical electrochemical cells with electrodes fabricated using a screen-printing method were examined by means of electrochemical impedance spectroscopy. The polarization resistance of the electrodes was 0.45 and 0.16 Ohm∙cm2 at 800 °C for the fuel and oxygen electrodes, respectively. The distribution of relaxation times method was applied for impedance data analysis. During tests of a single solid oxide fuel cell comprising a supporting triple-layer electrolyte having a thickness of 300 microns, a power density of about 160 mW/cm2 at 850 °C was obtained using wet hydrogen as fuel and air as an oxidizing gas. © 2020 by the authors.Russian Foundation for Basic Research, RFBR: 17‐08‐ 01227Government Council on Grants, Russian FederationFunding: The study was partly financially supported by the Russian Foundation for Basic Research (17‐08‐ 01227), Russian Federation Government, agreement 02.A03.21.0006 (No. 211) and “InEnergy” LTD agreement of 2018

    Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE) Conceptual Design Report Volume 2: The Physics Program for DUNE at LBNF

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    The Physics Program for the Deep Underground Neutrino Experiment (DUNE) at the Fermilab Long-Baseline Neutrino Facility (LBNF) is described

    Electrode kinetics in the system SmBaCo2O6–ή | Ce0.8Sm0.2O1.9 | SmBaCo2O6–ή

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    The polarization resistance dependences for the SmBaCo2O6-ÎŽ electrode in contact with the Ce0.8Sm0.2O1.9 electrolyte in the temperature range 600–700 °C and oxygen pressures of 2.3-520 kPa were obtained. Using the isotopic exchange and impedance spectroscopy data it was established that in the investigated ranges of T and pO2 the electrode process in the system is determined by three stages: oxygen exchange and diffusion in SmBaCo2O6-ÎŽ and oxygen diffusion over the gas phase.ĐŸĐŸĐ»ŃƒŃ‡Đ”ĐœŃ‹ Đ·Đ°ĐČĐžŃĐžĐŒĐŸŃŃ‚Đž ĐżĐŸĐ»ŃŃ€ĐžĐ·Đ°Ń†ĐžĐŸĐœĐœĐŸĐłĐŸ ŃĐŸĐżŃ€ĐŸŃ‚ĐžĐČĐ»Đ”ĐœĐžŃ ĐŽĐ»Ń ŃĐ»Đ”ĐșŃ‚Ń€ĐŸĐŽĐ° SmBaCo2O6–ή ĐČ ĐșĐŸĐœŃ‚Đ°ĐșŃ‚Đ” с Ce0.8Sm0.2O1.9 ŃĐ»Đ”ĐșŃ‚Ń€ĐŸĐ»ĐžŃ‚Đ” ĐČ ĐžĐœŃ‚Đ”Ń€ĐČалД Ń‚Đ”ĐŒĐżĐ”Ń€Đ°Ń‚ŃƒŃ€ 600–700 °Х Đž ĐŽĐ°ĐČĐ»Đ”ĐœĐžĐč ĐșĐžŃĐ»ĐŸŃ€ĐŸĐŽĐ° 2,3–520 ĐșПа. ĐĄ ĐżĐŸĐŒĐŸŃ‰ŃŒŃŽ ĐŽĐ°ĐœĐœŃ‹Ń… ĐžĐ·ĐŸŃ‚ĐŸĐżĐœĐŸĐłĐŸ ĐŸĐ±ĐŒĐ”ĐœĐ° Đž ĐžĐŒĐżĐ”ĐŽĐ°ĐœŃĐœĐŸĐč спДĐșŃ‚Ń€ĐŸŃĐșĐŸĐżĐžĐž ŃƒŃŃ‚Đ°ĐœĐŸĐČĐ»Đ”ĐœĐŸ, Ń‡Ń‚ĐŸ ĐČ ŃƒĐșĐ°Đ·Đ°ĐœĐœĐŸĐŒ ĐžĐœŃ‚Đ”Ń€ĐČалД Ń‚Đ”ĐŒĐżĐ”Ń€Đ°Ń‚ŃƒŃ€ Đž рО2 ŃĐ»Đ”ĐșŃ‚Ń€ĐŸĐŽĐœŃ‹Đč ĐżŃ€ĐŸŃ†Đ”ŃŃ ĐČ ĐžŃŃĐ»Đ”ĐŽŃƒĐ”ĐŒĐŸĐč ŃĐžŃŃ‚Đ”ĐŒĐ” ĐŸĐżŃ€Đ”ĐŽĐ”Đ»ŃĐ”Ń‚ŃŃ Ń‚Ń€Đ”ĐŒŃ ŃŃ‚Đ°ĐŽĐžŃĐŒĐž: ĐŸĐ±ĐŒĐ”Đœ Đž ĐŽĐžŃ„Ń„ŃƒĐ·ĐžŃ ĐșĐžŃĐ»ĐŸŃ€ĐŸĐŽĐ° ĐČ SmBaCo2O6–ή Đž ĐŽĐžŃ„Ń„ŃƒĐ·ĐžŃ ĐșĐžŃĐ»ĐŸŃ€ĐŸĐŽĐ° ĐżĐŸ ĐłĐ°Đ·ĐŸĐČĐŸĐč Ń„Đ°Đ·Đ”

    The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe

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    The preponderance of matter over antimatter in the early Universe, the dynamics of the supernova bursts that produced the heavy elements necessary for life and whether protons eventually decay --- these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our Universe, its current state and its eventual fate. The Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed plan for a world-class experiment dedicated to addressing these questions. LBNE is conceived around three central components: (1) a new, high-intensity neutrino source generated from a megawatt-class proton accelerator at Fermi National Accelerator Laboratory, (2) a near neutrino detector just downstream of the source, and (3) a massive liquid argon time-projection chamber deployed as a far detector deep underground at the Sanford Underground Research Facility. This facility, located at the site of the former Homestake Mine in Lead, South Dakota, is approximately 1,300 km from the neutrino source at Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino charge-parity symmetry violation and mass ordering effects. This ambitious yet cost-effective design incorporates scalability and flexibility and can accommodate a variety of upgrades and contributions. With its exceptional combination of experimental configuration, technical capabilities, and potential for transformative discoveries, LBNE promises to be a vital facility for the field of particle physics worldwide, providing physicists from around the globe with opportunities to collaborate in a twenty to thirty year program of exciting science. In this document we provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess.Comment: Major update of previous version. This is the reference document for LBNE science program and current status. Chapters 1, 3, and 9 provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess. 288 pages, 116 figure

    HE-LHC: The High-Energy Large Hadron Collider – Future Circular Collider Conceptual Design Report Volume 4

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    In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider (FCC-hh), a highest-luminosity high-energy lepton collider (FCC-ee), the corresponding 100 km tunnel infrastructure, as well as the physics opportunities of these two colliders, and a high-energy LHC, based on FCC-hh technology. This document constitutes the third volume of the FCC Conceptual Design Report, devoted to the hadron collider FCC-hh. It summarizes the FCC-hh physics discovery opportunities, presents the FCC-hh accelerator design, performance reach, and staged operation plan, discusses the underlying technologies, the civil engineering and technical infrastructure, and also sketches a possible implementation. Combining ingredients from the Large Hadron Collider (LHC), the high-luminosity LHC upgrade and adding novel technologies and approaches, the FCC-hh design aims at significantly extending the energy frontier to 100 TeV. Its unprecedented centre-of-mass collision energy will make the FCC-hh a unique instrument to explore physics beyond the Standard Model, offering great direct sensitivity to new physics and discoveries

    FCC-ee: The Lepton Collider – Future Circular Collider Conceptual Design Report Volume 2

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