135 research outputs found

    複数の脚本コーパスに現れた終助詞の比較分析

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    Senshu UniversitySenshu University / National Institute for Japanese Language and Linguistics会議名: 言語資源活用ワークショップ2019, 開催地: 国立国語研究所, 会期: 2019年9月2日−4日, 主催: 国立国語研究所 コーパス開発センター本稿では、脚本のテキストデータから構築したコーパスを分析した結果について述べる。今回、既に構築済みの『市川森一脚本コーパス』に加え、新たに『鎌田敏夫脚本コーパス』を構築した。これにより、違う書き手によって書かれた脚本の比較が可能となった。松下・丸山(2018)および松下(2019)では、『市川森一脚本コーパス』において主に終助詞に焦点を当て、分析を行い、性差が表れやすい終助詞の多用や、場面によって終助詞の表記が変わるといった点を明らかにした。今回、『鎌田敏夫脚本コーパス』に現れた終助詞の分布を分析し、『市川森一脚本コーパス』の終助詞の分布と比較した。その結果、2人の脚本家の間で終助詞の使用傾向が異なることがわかった。さらに実際の会話を収録した『日本語日常会話コーパス(CEJC)』で用いられる終助詞との比較を行ったところ、「話すことを前提として書かれた言葉」と実際の話し言葉では終助詞の分布が異なることがわかった

    脚本テキストに基づくコーパス文体論の可能性 : テレビドラマ脚本に注目して

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    Senshu UniversitySenshu University,National Institute for Japanese Language and Linguistics会議名: 言語資源活用ワークショップ2018, 開催地: 国立国語研究所, 会期: 2018年9月4日-5日, 主催: 国立国語研究所 コーパス開発センター現在、「日本脚本アーカイブズ推進コンソーシアム」により、1950年代以降のテレビドラマの脚本を収集し、それらを体系的に保存・アーカイブ化する活動が進められている。脚本は、「話されることを前提とした書き言葉」という点で特徴的な書き言葉であるが、これまでの言語研究の中で顧みられることは少なかった。収集した脚本をコーパス化して定量的に分析することにより、新たな言語学的利用の可能性が開かれると考えられる。そこで本発表では、脚本のテキスト化・コーパス化を試験的に実施した経緯を述べ、そのデータを使ってどのような言語研究が可能になるかについて論じる。故市川森一氏による、1970年代から2010年代までの脚本、32作品をテキスト化し、パイロットスタディを実施した。このような分析は、近現代における言語の短期的な変化の研究、ある作家の作品に関するコーパス文体論的研究などにつながると考えられる

    Peripheral Blood CD64 Levels Decrease in Crohn's Disease following Granulocyte and Monocyte Adsorptive Apheresis

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    Granulocyte and monocyte adsorptive apheresis (GMA) is reportedly useful as induction therapy for Crohn's disease (CD). However, the effects of GMA on CD64 have not been well characterized. We report here our assessment of CD64 expression on neutrophils before and after treatment with GMA in two patients with CD. The severity of CD was assessed with the CD activity index (CDAI). The duration of each GMA session was 60 min at a flow rate of 30 ml/min as per protocol. CD64 expression on neutrophils was measured by analyzing whole blood with a FACScan flow cytometer. In case 1, CD64 levels after each session of GMA tended to decrease compared to pretreatment levels, whereas in case 2, CD64 levels dropped significantly after treatment. The CDAI decreased after GMA in both cases 1 and 2. A significant correlation was noted between CDAI scores and CD64 levels in both cases. In conclusion, GMA reduced blood CD64 levels, which would be an important factor for the decrease of CDAI scores

    The Greenland Telescope: Construction, Commissioning, and Operations in Pituffik

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    In 2018, the Greenland Telescope (GLT) started scientific observation in Greenland. Since then, we have completed several significant improvements and added new capabilities to the telescope system. This paper presents a full review of the GLT system, a summary of our observation activities since 2018, the lessons learned from the operations in the Arctic regions, and the prospect of the telescope.Comment: 26 pages, 11 figures, and 8 tables. This is the version of the article before publication editing, as submitted by an author to Publications of the Astronomical Society of the Pacific. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record will be added when it becomes availabl

    A ring-like accretion structure in M87 connecting its black hole and jet

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    The nearby radio galaxy M87 is a prime target for studying black hole accretion and jet formation^{1,2}. Event Horizon Telescope observations of M87 in 2017, at a wavelength of 1.3 mm, revealed a ring-like structure, which was interpreted as gravitationally lensed emission around a central black hole^3. Here we report images of M87 obtained in 2018, at a wavelength of 3.5 mm, showing that the compact radio core is spatially resolved. High-resolution imaging shows a ring-like structure of 8.4_{-1.1}^{+0.5} Schwarzschild radii in diameter, approximately 50% larger than that seen at 1.3 mm. The outer edge at 3.5 mm is also larger than that at 1.3 mm. This larger and thicker ring indicates a substantial contribution from the accretion flow with absorption effects in addition to the gravitationally lensed ring-like emission. The images show that the edge-brightened jet connects to the accretion flow of the black hole. Close to the black hole, the emission profile of the jet-launching region is wider than the expected profile of a black-hole-driven jet, suggesting the possible presence of a wind associated with the accretion flow.Comment: 50 pages, 18 figures, 3 tables, author's version of the paper published in Natur

    A ring-like accretion structure in M87 connecting its black hole and jet

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    The nearby radio galaxy M87 is a prime target for studying black hole accretion and jet formation1,2. Event Horizon Telescope observations of M87 in 2017, at a wavelength of 1.3 mm, revealed a ring-like structure, which was interpreted as gravitationally lensed emission around a central black hole3. Here we report images of M87 obtained in 2018, at a wavelength of 3.5 mm, showing that the compact radio core is spatially resolved. High-resolution imaging shows a ring-like structure of [Formula: see text] Schwarzschild radii in diameter, approximately 50% larger than that seen at 1.3 mm. The outer edge at 3.5 mm is also larger than that at 1.3 mm. This larger and thicker ring indicates a substantial contribution from the accretion flow with absorption effects, in addition\ua0to the gravitationally lensed ring-like emission. The images show that the edge-brightened jet connects to the accretion flow of the black hole. Close to the black hole, the emission profile of the jet-launching region is wider than the expected profile of a black-hole-driven jet, suggesting the possible presence of a wind associated with the accretion flow

    THEMIS: A Parameter Estimation Framework for the Event Horizon Telescope

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    The Event Horizon Telescope (EHT) provides the unprecedented ability to directly resolve the structure and dynamics of black hole emission regions on scales smaller than their horizons. This has the potential to critically probe the mechanisms by which black holes accrete and launch outflows, and the structure of supermassive black hole spacetimes. However, accessing this information is a formidable analysis challenge for two reasons. First, the EHT natively produces a variety of data types that encode information about the image structure in nontrivial ways; these are subject to a variety of systematic effects associated with very long baseline interferometry and are supplemented by a wide variety of auxiliary data on the primary EHT targets from decades of other observations. Second, models of the emission regions and their interaction with the black hole are complex, highly uncertain, and computationally expensive to construct. As a result, the scientific utilization of EHT observations requires a flexible, extensible, and powerful analysis framework. We present such a framework, Themis, which defines a set of interfaces between models, data, and sampling algorithms that facilitates future development. We describe the design and currently existing components of Themis, how Themis has been validated thus far, and present additional analyses made possible by Themis that illustrate its capabilities. Importantly, we demonstrate that Themis is able to reproduce prior EHT analyses, extend these, and do so in a computationally efficient manner that can efficiently exploit modern high-performance computing facilities. Themis has already been used extensively in the scientific analysis and interpretation of the first EHT observations of M87

    SYMBA: An end-to-end VLBI synthetic data generation pipeline: Simulating Event Horizon Telescope observations of M 87

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    Context. Realistic synthetic observations of theoretical source models are essential for our understanding of real observational data. In using synthetic data, one can verify the extent to which source parameters can be recovered and evaluate how various data corruption effects can be calibrated. These studies are the most important when proposing observations of new sources, in the characterization of the capabilities of new or upgraded instruments, and when verifying model-based theoretical predictions in a direct comparison with observational data. Aims. We present the SYnthetic Measurement creator for long Baseline Arrays (SYMBA), a novel synthetic data generation pipeline for Very Long Baseline Interferometry (VLBI) observations. SYMBA takes into account several realistic atmospheric, instrumental, and calibration effects. Methods. We used SYMBA to create synthetic observations for the Event Horizon Telescope (EHT), a millimetre VLBI array, which has recently captured the first image of a black hole shadow. After testing SYMBA with simple source and corruption models, we study the importance of including all corruption and calibration effects, compared to the addition of thermal noise only. Using synthetic data based on two example general relativistic magnetohydrodynamics (GRMHD) model images of M 87, we performed case studies to assess the image quality that can be obtained with the current and future EHT array for different weather conditions. Results. Our synthetic observations show that the effects of atmospheric and instrumental corruptions on the measured visibilities are significant. Despite these effects, we demonstrate how the overall structure of our GRMHD source models can be recovered robustly with the EHT2017 array after performing calibration steps, which include fringe fitting, a priori amplitude and network calibration, and self-calibration. With the planned addition of new stations to the EHT array in the coming years, images could be reconstructed with higher angular resolution and dynamic range. In our case study, these improvements allowed for a distinction between a thermal and a non-thermal GRMHD model based on salient features in reconstructed images

    First M87 Event Horizon Telescope Results. IV. Imaging the Central Supermassive Black Hole

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    We present the first Event Horizon Telescope (EHT) images of M87, using observations from April 2017 at 1.3 mm wavelength. These images show a prominent ring with a diameter of similar to 40 mu as, consistent with the size and shape of the lensed photon orbit encircling the "shadow" of a supermassive black hole. The ring is persistent across four observing nights and shows enhanced brightness in the south. To assess the reliability of these results, we implemented a two-stage imaging procedure. In the first stage, four teams, each blind to the others' work, produced images of M87 using both an established method (CLEAN) and a newer technique (regularized maximum likelihood). This stage allowed us to avoid shared human bias and to assess common features among independent reconstructions. In the second stage, we reconstructed synthetic data from a large survey of imaging parameters and then compared the results with the corresponding ground truth images. This stage allowed us to select parameters objectively to use when reconstructing images of M87. Across all tests in both stages, the ring diameter and asymmetry remained stable, insensitive to the choice of imaging technique. We describe the EHT imaging procedures, the primary image features in M87, and the dependence of these features on imaging assumptions

    Monitoring the Morphology of M87* in 2009–2017 with the Event Horizon Telescope

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    The Event Horizon Telescope (EHT) has recently delivered the first resolved images of M87*, the supermassive black hole in the center of the M87 galaxy. These images were produced using 230 GHz observations performed in 2017 April. Additional observations are required to investigate the persistence of the primary image feature—a ring with azimuthal brightness asymmetry—and to quantify the image variability on event horizon scales. To address this need, we analyze M87* data collected with prototype EHT arrays in 2009, 2011, 2012, and 2013. While these observations do not contain enough information to produce images, they are sufficient to constrain simple geometric models. We develop a modeling approach based on the framework utilized for the 2017 EHT data analysis and validate our procedures using synthetic data. Applying the same approach to the observational data sets, we find the M87* morphology in 2009–2017 to be consistent with a persistent asymmetric ring of ~40 μas diameter. The position angle of the peak intensity varies in time. In particular, we find a significant difference between the position angle measured in 2013 and 2017. These variations are in broad agreement with predictions of a subset of general relativistic magnetohydrodynamic simulations. We show that quantifying the variability across multiple observational epochs has the potential to constrain the physical properties of the source, such as the accretion state or the black hole spin
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