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A method of calculating the mean life-time of solar granules 29

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A method of calculating the mean life-time of solar granules

第29届中国控制与决策会议

作者： Jianshu Wang Song Feng Yunnan Key Laboratory of Computer Technology Application Faculty of Information Engineering and Automation Kunming University of Science and Technology

ISBN: (纸本)9781509046584

Solar granulation is a kind of morphological characteristics of solar photosphere caused by convective *** of the mechanism of convective motion,when we calculated the mean life-time of solar granules,we can get the time of convective *** are many methods based on the classification of solar granules and tracking solar granules to calculate the mean life-time of solar *** a result of the existence time of solar granules is very short and the evolution is more complex,identifying the fragmentation and merging of solar granules will get us into *** this paper,we present a power spectrum analysis based on periodic analysis method to calculate the mean life-time of solar ***,we use the κ-ω filter to remove the 5-minute *** removing the 5-minute oscillations can we more accurately calculate the mean life-time of solar ***,we use gradient transformation to remove the direct current component(DC component) and reduce spectral energy leakage with the Hamming ***,using the function of Periodogram calculates the mean life-time of solar *** order to verify the accuracy of the method,we set three data to calculate the mean life-time of solar *** final results of calculating the mean life-time of solar granules are 9.24 min,9.04 min and 10.67 min *** our method is effective and accurate compared with the results of other literature.

关键词： Solar granules k-ω filter Power spectrum The mean life-time

AbdomenCT-1K: Is abdominal organ segmentation a solved problem?

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arXiv 2020年

作者： Ma, Jun Zhang, Yao Gu, Song Zhu, Cheng Ge, Cheng Zhang, Yichi An, Xingle Wang, Congcong Wang, Qiyuan Liu, Xin Cao, Shucheng Zhang, Qi Liu, Shangqing Wang, Yunpeng Li, Yuhui He, Jian Yang, Xiaoping Department of Mathematics Nanjing University of Science and Technology China Institute of Computing Technology Chinese Academy of Sciences University of Chinese Academy of Sciences China AI Lab Lenovo Research School of Automation Nanjing University of Information Science and Technology China Shenzhen Haichuang Medical CO. LTD. China Institute of Bioinformatics and Medical Engineering Jiangsu University of Technology China School of Biological Science and Medical Engineering Beihang University China Beijing Infervision Technology CO. LTD. China School of Computer Science and Engineering Tianjin University of Technology China Department of Computer Science Norwegian University of Science and Technology Norway School of Electronic Science and Engineering Nanjing University China Suzhou LungCare Medical Technology Co. Ltd China Bioengineering Biological and Environmental Science and Engineering Division King Abdullah University of Science and Technology Saudi Arabia Department of Computer and Information Science Faculty of Science and Technology University of Macau China School of Biomedical Engineering Southern Medical University China Institutes of Biomedical Sciences Fudan University China Computational Biology University of Southern California United States Department of Radiology Nanjing Drum Tower Hospital The Affiliated Hospital Nanjing University Medical School China Department of Mathematics Nanjing University China

With the unprecedented developments in deep learning, automatic segmentation of main abdominal organs seems to be a solved problem as state-of-the-art (SOTA) methods have achieved comparable results with inter-rater variability on many benchmark datasets. However, most of the existing abdominal datasets only contain single-center, single-phase, single-vendor, or single-disease cases, and it is unclear whether the excellent performance can generalize on diverse datasets. This paper presents a large and diverse abdominal CT organ segmentation dataset, termed AbdomenCT-1K, with more than 1000 (1K) CT scans from 12 medical centers, including multi-phase, multi-vendor, and multi-disease cases. Furthermore, we conduct a large-scale study for liver, kidney, spleen, and pancreas segmentation and reveal the unsolved segmentation problems of the SOTA methods, such as the limited generalization ability on distinct medical centers, phases, and unseen diseases. To advance the unsolved problems, we further build four organ segmentation benchmarks for fully supervised, semi-supervised, weakly supervised, and continual learning, which are currently challenging and active research topics. Accordingly, we develop a simple and effective method for each benchmark, which can be used as out-of-the-box methods and strong baselines. We believe the AbdomenCT-1K dataset will promote future in-depth research towards clinical applicable abdominal organ segmentation methods. © 2020, CC BY-NC-SA.

关键词： computerized tomography

Universal enzymatic numerical P systems with small number of enzymatic variables

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Science China(Information Sciences) 2018年第9期61卷 38-49页

作者： Zhiqiang ZHANG Tingfang WU ANDrei P■UN Linqiang PAN Key Laboratory of Image Information Processing and Intelligent Control of Education Ministry of China School of Automation Huazhong University of Science and Technology Department of Computer Science Faculty of Mathematics and Computer ScienceUniversity of Bucharest Bioinformatics Department National Institute of Research and Development for Biological Sciences School of Electric and Information Engineering Zhengzhou University of Light Industry

Numerical P systems(for short, NP systems) are distributed and parallel computing models inspired from the structure of living cells and economics. Enzymatic numerical P systems(for short, ENP systems) are a variant of NP systems, which have been successfully applied in designing and implementing controllers for mobile robots. Since ENP systems were proved to be Turing universal, there has been much work to simplify the universal systems, where the complexity parameters considered are the number of membranes, the degrees of polynomial production functions or the number of variables used in the *** the number of enzymatic variables, which is essential for ENP systems to reach universality, has not been investigated. Here we consider the problem of searching for the smallest number of enzymatic variables needed for universal ENP systems. We prove that for ENP systems as number acceptors working in the all-parallel or one-parallel mode, one enzymatic variable is sufficient to reach universality; while for the one-parallel ENP systems as number generators, two enzymatic variables are sufficient to reach *** results improve the best known results that the numbers of enzymatic variables are 13 and 52 for the all-parallel and one-parallel systems, respectively.

关键词： bio-inspired computing numerical P system mobile robot membrane controller universality

The medical segmentation decathlon

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arXiv 2021年

作者： Antonelli, Michela Reinke, Annika Bakas, Spyridon Farahani, Keyvan Kopp-Schneider, Annette Landman, Bennett A. Litjens, Geert Menze, Bjoern Ronneberger, Olaf Summers, Ronald M. van Ginneken, Bram Bilello, Michel Bilic, Patrick Christ, Patrick F. Do, Richard K.G. Gollub, Marc J. Heckers, Stephan H. Huisman, Henkjan Jarnagin, William R. McHugo, Maureen K. Napel, Sandy Golia Pernicka, Jennifer S. Rhode, Kawal Tobon-Gomez, Catalina Vorontsov, Eugene Hulsmon, Hankan Meakin, James A. Ourselin, Sebastien Wiesenfarth, Manuel Arbeláez, Pablo Bae, Byeonguk Chen, Sihong Daza, Laura Feng, Jianjiang He, Baochun Isensee, Fabian Ji, Yuanfeng Jia, Fucang Kim, Namkug Kim, Ildoo Merhof, Dorit Pai, Akshay Park, Beomhee Perslev, Mathias Rezaiifar, Ramin Rippel, Oliver Sarasua, Ignacio Shen, Wei Son, Jaemin Wachinger, Christian Wang, Liansheng Wang, Yan Xia, Yingda Xu, Daguang Xu, Zhanwei Zheng, Yefeng Simpson, Amber L. Maier-Hein, Lena Cardoso, M. Jorge School of Biomedical Engineering & Imaging Sciences King’s College London London United Kingdom Heidelberg Germany Heidelberg Germany Faculty of Mathematics and Computer Science University of Heidelberg Heidelberg Germany University of Pennsylvania PhiladelphiaPA United States BethesdaMD United States Heidelberg Germany Electrical Engineering and Computer Science Vanderbilt University NashvilleTN United States Radboud University Medical Center Radboud Institute for Health Sciences Nijmegen Netherlands Quantitative Biomedicine University of Zurich Zurich Switzerland DeepMind London United Kingdom School of Computing Department of Biomedical and Molecular Sciences Queen’s University KingstonON Canada Department of Surgery Memorial Sloan Kettering Cancer Center New YorkNY United States BethesdaMD United States Department of Informatics Technische Universität München Germany Department of Radiology Memorial Sloan Kettering Cancer Center New YorkNY United States Department of Psychiatry & Behavioral Sciences Vanderbilt University Medical Center NashvilleTN United States Department of Radiology Stanford University StanfordCA United States Department of Computer Science and Software Engineering École Polytechnique de Montréal Department of Radiology Perelman School of Medicine University of Pennsylvania PhiladelphiaPA United States Department of Pathology and Laboratory Medicine Perelman School of Medicine University of Pennsylvania PhiladelphiaPA United States Medical Faculty University of Heidelberg Heidelberg Germany VUNO Inc. Seoul Korea Republic of Universidad de los Andes Colombia Department of Automation Tsinghua University Beijing China Heidelberg Germany Department of Computer Science Xiamen University Xiamen361005 China Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Shenzhen China Kakao Brain Korea Republic of Institute of Imaging & Computer Vision RWTH Aachen University Aachen Germany Cere

International challenges have become the de facto standard for comparative assessment of image analysis algorithms given a specific task. Segmentation is so far the most widely investigated medical image processing task, but the various segmentation challenges have typically been organized in isolation, such that algorithm development was driven by the need to tackle a single specific clinical problem. We hypothesized that a method capable of performing well on multiple tasks will generalize well to a previously unseen task and potentially outperform a custom-designed solution. To investigate the hypothesis, we organized the Medical Segmentation Decathlon (MSD)—a biomedical image analysis challenge, in which algorithms compete in a multitude of both tasks and modalities. The underlying data set was designed to explore the axis of difficulties typically encountered when dealing with medical images, such as small data sets, unbalanced labels, multi-site data and small objects. The MSD challenge confirmed that algorithms with a consistent good performance on a set of tasks preserved their good average performance on a different set of previously unseen tasks. Moreover, by monitoring the MSD winner for two years, we found that this algorithm continued generalizing well to a wide range of other clinical problems, further confirming our hypothesis. Three main conclusions can be drawn from this study: (1) state-of-the-art image segmentation algorithms are mature, accurate, and generalize well when retrained on unseen tasks;(2) consistent algorithmic performance across multiple tasks is a strong surrogate of algorithmic generalizability;(3) the training of accurate AI segmentation models is now commoditized to non AI *** Codes 68T07. © 2021, CC BY-NC-SA.

关键词： Image segmentation

Magnetic connectivity between the light bridge and penumbra in a sunspot

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arXiv 2020年

作者： Feng, Song Miao, Yuhu Yuan, Ding Qu, Zhongquan Nakariakov, Valery M. Yunnan Key Laboratory of Computer Technology Application Faculty of Information Engineering and Automation Kunming University of Science and Technology Kunming650500 China Yunnan Astronomical Observatory Chinese Academy of Sciences PO Box 110 Kunming650011 China Institute of Space Science and Applied Technology Harbin Institute of Technology Shenzhen Guangdong518055 China Centre for Fusion Space and Astrophysics Department of Physics University of Warwick CV4 7AL United Kingdom St Petersburg Branch Special Astrophysical Observatory Russian Academy of Sciences St Petersburg196140 Russia

A light bridge is a prominent structure commonly observed within a sunspot. Its presence usually triggers a wealth of dynamics in a sunspot, and has a lasting impact on sunspot evolution. However, the fundamental structure of light bridges is still not well understood. In this study, we used the high-resolution spectropolarimetry data obtained by the Solar Optical Telescope onboard the Hinode satellite to analyze the magnetic and thermal structure of a light bridge at AR 12838. We also combined the high-cadence 1700 Å channel data provided by the Atmospheric Imaging Assembly onboard the Solar Dynamic Observatory to study the dynamics on this bridge. We found that a pair of blue and red Doppler shift patches at two ends of this bridge, this pattern appears to be the convective motion directed by the horizontal component of the magnetic field aligned with the spine of this bridge. Paired upward and downward motions implies that the light bridge could have a two-legged or undulate magnetic field. Significant four minute oscillations in the emission intensity of the 1700 Å bandpass were detected at two ends, which had overlap with the paired blue and red shift patches. The oscillatory signals at the light bridge and the penumbra were highly correlated with each other. Although they are separated in space at the photosphere, the periodicity seems to have a common origin from the underneath. Therefore, we infer that the light bridge and penumbra could share a common magnetic source and become fragmented at the photosphere by magneto-convection. Copyright © 2020, The Authors. All rights reserved.

关键词： Magnetohydrodynamics

Preflare very long-periodic pulsations observed in Hα emission before the onset of a solar flare

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arXiv 2020年

作者： Li, Dong Feng, Song Su, Wei Huang, Yu Key Laboratory of Dark Matter and Space Astronomy Purple Mountain Observatory CAS Nanjing210033 China State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing100190 China CAS Key Laboratory of Solar Activity National Astronomical Observatories Beijing100101 China Yunnan Key Laboratory of Computer Technology Application Faculty of Information Engineering and Automation Kunming University of Science and Technology Kunming650500 China MOE Key Laboratory of Fundamental Physical Quantities Measurements School of Physics Huazhong University of Science and Technology Wuhan430074 China

Context. Very long-periodic pulsations during preflare phases (preflare-VLPs) have been detected in the full-disk solar soft X-Ray (SXR) flux (see Tan et al. 2016). They may be regarded as precursors to solar flares and may help us better understand the trigger mechanism of solar flares. Aims. In this letter, we report a preflare-VLP event prior to the onset of an M1.1 circular-ribbon flare on 2015 October 16. It was simultaneously observed in Hα, SXR, and extreme ultraviolet (EUV) wavelengths. Methods. The SXR fluxes in 1−8 Å and 1−70 Å were recorded by the Geostationary Operational Environmental Satellite (GOES) and Extreme Ultraviolet Variability Experiment (EVE), respectively;the light curves in Hα and EUV 211 Å were integrated over a small local region, which were measured by the 1m New Vacuum Solar Telescope (NVST) and the Atmospheric Imaging Assembly (AIA), respectively. The preflare-VLP is identified as the repeat and quasi-periodic pulses in light curves during preflare phase. The quasi-periodicity can be determined from the Fourier power spectrum with Markov chain Monte Carlo (MCMC)-based Bayesian (e.g., Liang et al. 2020). Results. Seven well-developed pulses are found before the onset of an M1.1 circular-ribbon flare. They are firstly seen in the local light curve in Hα emission and then discovered in full-disk SXR fluxes in GOES 1−8 Å and ESP 1−70 Å, as well as the local light curve in AIA 211 Å. These well-developed pulses can be regarded as the preflare-VLP, which might be modulated by LRC-circuit oscillation in the current-carrying plasma loop. The quasi-period is estimated to be ∼9.3 minutes. Conclusions. We present the first report of a preflare-VLP event in the local Hα line and EUV wavelength, which could be considered a precursor of a solar flare. This finding should therefore prove useful for the prediction of solar flares, especially for powerful flares. Copyright © 2020, The Authors. All rights reserved.

关键词： Gamma rays

Advances in Intelligent Systems and Computing

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Preface

Advances in Intelligent Systems and Computing 2019年 837卷 v-vi页

作者： Matoušek, Radek Department of Applied Computer Science Institute of Automation and Computer Science Faculty of Mechanical Engineering Brno University of Technology Brno Czech Republic

Failure modes and effects analysis for an automatic level control system

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Failure modes and effects analysis for an automatic level co...

IEEE International Conference on automation, Quality and Testing, Robotics, AQTR

作者： Claudiu Bâlc Alexandru Cretu Dan Iudean Horaţiu Laslo Szilárd Enyedi Radu Munteanu Faculty of Electrical Engineering Technical University of Cluj-Napoca Cluj-Napoca Romania Faculty of Automation and Computer Science Technical University of Cluj-Napoca Cluj-Napoca Romania

An Automatic Level Control System is an important process that needs to be properly designed and monitored in order to determine and eliminate the critical failures that could result in the loss of the system. Water resource availability is an important problem and in a water distribution process the level and flow must be always known and monitored to keep the system running at full capacity and with minimal disruptions. If the systems are properly designed and the critical failures eliminated the process availability increases considerably. This paper presents a Failure Modes and Effects Analysis for an automatic level control system. This analysis gives an overview on the critical components of the system.

关键词： Level control Reliability Standards Sensor systems Manufacturing processes Process control

Availability factor of a PV power plant: evaluation based on generation and inverter running periods

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Energy Procedia 2018年 147卷 71-77页

作者： Nallapaneni Manoj Kumar Srikar Dasari Jagathpally Bhagwan Reddy Faculty of Electrical and Electronics Engineering Universiti Malaysia Pahang Pahang Pekan 26600 Malaysia Automation and Power Engineering Faculty of Electrical Engineering Media Engineering and Computer Science THD Technische Hochschule Deggendorf Edlmairstr Deggendorf 94469 Germany Department of Electrical and Electronics Engineering Nalla Malla Reddy Engineering College Ghatkesar Telangana 500 088 India

In a solar PV power plant, the plant availability factor is one of the important factors to be evaluated. This depends on the operative functioning of various components and grid regulation. In this paper, a simple method is proposed to evaluate the availability factors of a solar PV plant by considering the real time data of 1 MWp solar power plant that was commissioned in 2011 in south India. Generation start time, end time, and actual running periods of the inverter were selected as prominent data in the study. A consecutive five financial years of data (2011–2012; 2012–2013; 2013–2014; 2014–2015; 2015–2016) was used to observe the variations in availability factors of inverters, as well as the plant availability factors. From the analysis, it is observed that tripping time greatly effects the availability factor of inverter as well as the PV plant. The variation in availability factor over the five consecutive financial years is seen to be within the range of 92.44 % to 95.69 %. This clearly states that, on average 4.31 % to 7.56 %, the installed solar PV power is technically not generated any power. Hence, estimating the availability factor could be very much essential to deal with the performance of the PV systems and possible options of reducing energy losses due to availability factors could be suggested.

关键词： solar energy PV power plant inverter availability factor plant availability factor inverter outages PV plant generation periods