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Comparative study of the W UMa type binaries S Ant and ϵ CrA

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arXiv 2024年

作者： Bakış, Volkan Budding, Edwin Erdem, Ahmet Love, Tom Blackford, Mark G. Zihao, Wu Tang, Adam Rhodes, Michael D. Banks, Timothy S. Department of Space Sciences and Technologies Faculty of Sciences Akdeniz University Antalya07058 Turkey Carter Observatory 40 Salamanca Road Kelburn Wellington6012 New Zealand School of Chemical & Physical Sciences Victoria University of Wellington PO Box 600 Wellington6140 New Zealand Astrophysics Research Center & Ulupınar Observatory Çanakkale Onsekiz Mart University ÇanakkaleTR-17100 Turkey Variable Stars South RASNZ PO Box 3181 Wellington6011 New Zealand Variable Stars South Congarinni Observatory CongarinniNSW2447 Australia Dept. Statistics & Data Science National University of Singapore 6 Science Drive 2 Singapore117546 Singapore University of Chicago Laboratory Schools 1362 E 59th St ChicagoIL60637 United States Brigham Young University ProvoUT84602 United States Nielsen 675 6th Ave New YorkNY10011 United States Dept. of Physical Science & Engineering Harper College 1200 W Algonquin Rd PalatineIL60067 United States

Contact binaries challenge contemporary stellar astrophysics with respect to their incidence, structure and evolution. We explore these issues through a detailed study of two bright examples: S Ant and ϵ CrA, that permit high-resolution spectroscopy at a relatively good S/N ratio. The availability of high-quality photometry, including data from the TESS satellite as well as Gaia parallaxes, allows us to apply the Russell paradigm to produce reliable up-to-date information on the physical properties of these binaries. As a result, models of their interactive evolution, such as the thermal relaxation oscillator scenario, can be examined. Mass transfer between the components is clearly evidenced, but the variability of the O’Connell effect over relatively short time scales points to irregularities in the mass transfer or accretion processes. Our findings indicate that S Ant may evolve into an R CMa type Algol, while the low mass ratio of ϵ CrA suggests a likely merger of its components in the not-too-distant future. © 2024, CC BY.

关键词： Stars

Base flow decomposition for complex moving objects in linear hydrodynamics: application to helix-shaped flagellated microswimmers

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arXiv 2021年

作者： Zhang, Ji Chinappi, Mauro Biferale, Luca Beijing Computational Science Research Center Beijing100193 China Department of Industrial Engineering University of Rome Tor Vergata Via del Politecnico 1 Roma00133 Italy Dept. of Physics and INFN University of Rome Tor Vergata Via della Ricerca Scientifica 1 Roma00133 Italy

The motion of microswimmers in complex flows is ruled by the interplay between swimmer propulsion and the dynamics induced by the fluid velocity field. Here we study the motion of a chiral microswimmer whose propulsion is provided by the spinning of a helical tail with respect to its body in a simple shear flow. Thanks to an efficient computational strategy that allowed us to simulate thousands of different trajectories, we show that the tail shape dramatically affects the swimmer’s motion. In the shear dominated regime, the swimmers carrying an elliptical helical tail show several different Jeffery-like (tumbling) trajectories depending on their initial configuration. As the propulsion torque increases, a progressive regularization of the motion is observed until, in the propulsion dominated regime, the swimmers converge to the same final trajectory independently on the initial configuration. Overall, our results show that elliptical helix swimmer presents a much richer variety of trajectories with respect to the usually studied circular helix tails. Copyright © 2021, The Authors. All rights reserved.

关键词： Trajectories

An Online Learning Approach to Dynamic Pricing and Capacity Sizing in Service Systems

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arXiv 2020年

作者： Chen, Xinyun Liu, Yunan Hong, Guiyu School of Data Science Chinese University of Hong Kong Shenzhen China Dept. of Industrial and Systems Engineering North Carolina State University United States

We study a dynamic pricing and capacity sizing problem in a GI/GI/1 queue, where the service provider's objective is to obtain the optimal service fee p and service capacity µ so as to maximize the cumulative expected profit (the service revenue minus the staffing cost and delay penalty). Due to the complex nature of the queueing dynamics, such a problem has no analytic solution so that previous research often resorts to heavy-traffic analysis where both the arrival rate and service rate are sent to infinity. In this work we propose an online learning framework designed for solving this problem which does not require the system's scale to increase. Our framework is dubbed Gradient-based Online Learning in Queue (GOLiQ). GOLiQ organizes the time horizon into successive operational cycles and prescribes an efficient procedure to obtain improved pricing and staffing policies in each cycle using data collected in previous cycles. data here include the number of customer arrivals, waiting times, and the server's busy times. The ingenuity of this approach lies in its online nature, which allows the service provider do better by interacting with the environment. Effectiveness of GOLiQ is substantiated by (i) theoretical results including the algorithm convergence and regret analysis (with a logarithmic regret bound), and (ii) engineering confirmation via simulation experiments of a variety of representative GI/GI/1 queues. Copyright © 2020, The Authors. All rights reserved.

关键词： Costs

Air quality data prediction using data analytics

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AIP Conference Proceedings 2024年第1期2742卷

作者： Senthil Kumar Sidharthan Kalaiarasan Nancy Anvar Shathik Kavietha Dept. of Computer Science and Egg Chennai Institute of Technology Chennai Tamilnadu India Department of Information Technology Sri Krishna College of Engineering and Technology Coimbatore Tamilnadu India Saveetha School of Engineering Saveetha Institute of Medical and technical sciences(Deemed to be university) Chennai India Department of Cloud Technology & Data Science iNurture Education Solutions Srinivas University College of Engineering & Technology Bangalore India. Department of Computer Science and Engineering Sri Sairam Institute of Technology Chennai India.

Air pollution is usually described as the release into the atmosphere of contaminants which are harmful to human health and the environment. It may be described as one of the most serious risks human beings have ever faced because to the growing more catastrophic problem of air pollution in the globe. A description is provided of how our air quality sensor system is designed, implemented and optimised, which provides a live and fine grain air quality map of the area under surveillance. The average joint failure in the generated real-time air quality map should be maintained to a minimal when unmeasured data values as part of the objective are deducted. In terms of studying the quality issues, Big data Technology has been recommended to be utilised in order to organise the air quality sensing equipment sensing tasks appropriately. In addition, the prediction of air quality based on climatic conditions is explored using various machine learning techniques for the data given.

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Correlation Analysis with Experimental Procedures and Peak Structures in Xps Spectral Round-Robin Tests on Mno Powder Sample

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SSRN

SSRN 2022年

作者： Murakami, Ryo Harada, Yoshitomo Sonobayashi, Yutaka Oji, Hiroshi Makino, Hisao Tanaka, Hiromi Taguchi, Hideyuki Sakamoto, Takanori Morita, Haruka Wakamori, Akihiko Kibe, Naoko Nishida, Shinsuke Nagata, Kenji Shinotsuka, Hiroshi Shouno, Hayaru Yoshikawa, Hideki The University of Electro-Communications Graduate School of Informatics and Engineering Chofu182-8585 Japan National Institute for Materials Science Research and Services Division of Materials Data and Integrated System Ibaraki Tsukuba305-0044 Japan Kyoto University Department of Materials Science and Engineering Kyoto606-8501 Japan Nagoya University Synchrotron radiation Research center Nagoya464-8603 Japan Kochi University of Technology School of Systems Engineering Japan National Institute of Technology Yonago College Department of Electrical and Computer Engineering Japan Nihon Parkerizing Co. Ltd Central Research Laboratories Kanagawa 254-0012 Japan JX Nippon Mining & Metals Corporation Technology Development Center Japan Melco Semiconductor Engineering Corporation Chemical Analysis & Evaluation Engineering Dept. Fukuoka Japan Kobelco Welding TechnoSolutions Co. Technical Solution Dept. Ltd Kanagawa 251-8551 Japan Furukawa Electric Co. Ltd Analysis Technology Center Sustainable Technology Laboratorie Kanagawa 220-0073 Japan

Spectral measurements provide valuable information on the electronic states and crystal structures of materials. In particular, X-ray photoelectron spectroscopy (XPS) can facilitate analysis of the chemical bond state of material surfaces. In the analysis of XPS spectra, the spectrum to be measured is typically compared to a reference spectrum measured on a known single-phase sample. Therefore, establishing a reference spectral database is imperative. In this study, round-robin tests of XPS spectra are performed with the aim of obtaining recommended XPS reference spectra and experimental procedures, including preprocessing. Determining the variations in peak structures between instrument- and sample-derived spectral shapes, and quantitatively discussing them in round-robin tests of XPS spectra are challenging. Therefore, an analysis method that automatically determines the above mentioned variations and extracts the samplederived common spectral structures is developed. This study presents a new approach to the quantitative analysis of round-robin tests of XPS spectra. The required common © 2022, The Authors. All rights reserved.

关键词： X ray photoelectron spectroscopy

On the unification of rational terms

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Computer Software

Computer Software 2018年第4期35卷 151-163页

作者： Iwami, Munehiro Dept. of Information Systems Design and Data Science Interdisciplinary Faculty of Science and Engineering Shimane University Japan

First-order unification algorithms on finite terms are formalized by inference rules, and their termination, soundness and completeness have been presented in many papers. Unification algorithms on rational terms have also been presented in several papers. However, it has not been shown that the solution of the set obtained by inference rules from a given set of equations coincides with the rational substitution which is the most general unifier of the original set. Furthermore, the precise proofs of termination, soundness and completeness are not clear in many cases. In this paper, we revisit the foundations of unification algorithm on rational terms within the framework of term rewriting systems. First, we show that the solution of a regular system is the most general unifier of the set of equations corresponding to the regular system. Next, we reformulate the unification algorithm on rational terms by inference rules, and then give the proofs of its termination, soundness and completeness, respectively. Finally, we show that a unifiable set of equations has a most general unifier as a rational substitution. © 2018 IEEE Computer Society. All Rights Reserved.

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madmpy: A Python library for creating and validating data Management Plans

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SoftwareX 2025年 31卷

作者： Alberto Ballesteros-Rodríguez Miguel-Ángel Sicilia Elena García-Barriocanal Biomedical Data Science and Engineering Research Group Ramón y Cajal University Hospital and Ramón y Cajal Health Research Institute (IRYCIS) 28034 Madrid Spain Universidad de Alcalá Computer Science dept. Polytechnic Building Ctra. Barcelona km. 33.6 28871 Alcalá de Henares (Madrid) Spain

data Management Plans (DMPs) are documents that describe the data used and produced during the course of research projects. Machine-actionable DMPs (maDMPs) are plans written in computer-readable formats. They are designed to support the automation of data-generation processes in scientific research. The madmpy Python package validates maDMPs that follow any version of the RDA DMP Common Standard. These plans can be written in JSON format or built programmatically. It also supports institution- or domain-specific extensions and additional validations that adhere to the standard. The library serves as a building block for research data engineering workflows. It promotes data management and accountability through the use of structured DMPs.

关键词： data Management Plan Machine-actionable data validation FAIR

Google COVID-19 community mobility reports: Insights from multi-criteria decision making

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arXiv 2020年

作者： da Silva, Gabriela Cavalcante Oliveira, Sabrina Wanner, Elizabeth F. Bezerra, Leonardo C.T. Brazil Postgraduate Program in Mathematical and Computational Modeling CEFET-MG Brazil Computer Engineering Dept. CEFET-MG Brazil Computer Science Group Aston University United Kingdom

Social distancing (SD) has been critical in the fight against the novel coronavirus disease (COVID-19). To aid SD monitoring, many technology companies have made available mobility data, the most prominent example being the community mobility reports (CMR) provided by Google. Given the wide range of research fields that have been drawing insights from CMR data, there has been a rising concern for methodological discussion on how to use them. Indeed, Google recently released their own guidelines, concerning the nature of the place categories and the need for calibrating regional values. In this work, we discuss how measures developed in the field of multi-criteria decision making (MCDM) might benefit researchers analyzing this data. Concretely, we discuss how Pareto dominance and performance measures adopted in MCDM enable the mobility evaluation for (i) multiple categories for a given time period and (ii) multiple categories over multiple time periods. We empirically demonstrate these approaches conducting both a region- and country-level analysis, comparing some of the most relevant outbreak examples from different continents. Copyright © 2020, The Authors. All rights reserved.

关键词： Coronavirus

Generative pre-training for paraphrase generation by representing and predicting spans in exemplars

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arXiv 2020年

作者： Bui, Tien-Cuong Le, Van-Duc To, Hai-Thien Cha, Sang Kyun Dept. Electrical and Computer Engineering Seoul National University Seoul Korea Republic of Graduate School of Data Science Seoul National University Seoul Korea Republic of

Paraphrase generation is a long-standing problem and serves an essential role in many natural language processing problems. Despite some encouraging results, recent methods either confront the problem of favoring generic utterance or need to retrain the model from scratch for each new dataset. This paper presents a novel approach to paraphrasing sentences, extended from the GPT-2 model. We develop a template masking technique, named first-order masking, to masked out irrelevant words in exemplars utilizing POS taggers. So that, the paraphrasing task is changed to predicting spans in masked templates. Our proposed approach outperforms competitive baselines, especially in the semantic preservation aspect. To prevent the model from being biased towards a given template, we introduce a technique, referred to as second-order masking, which utilizes Bernoulli distribution to control the visibility of the first-order-masked template’s tokens. Moreover, this technique allows the model to provide various paraphrased sentences in testing by adjusting the second-order-masking level. For scale-up objectives, we compare the performance of two alternatives template-selection methods, which shows that they were equivalent in preserving semantic information. © 2020, CC-BY-NC-SA.

关键词： computational linguistics