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Plate and plume tectonics:Numerical simulation and seismic tomography

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Geoscience Frontiers 2015年第1期6卷 1-2页

作者： Masaki yoshida Department of Deep Earth Structure and Dynamics Research Jaan Agency for Marine-Earth Science and Technology(JAMSTEC)

About three decades after the establishment of the plate tec- tonics theory in the late 1960s, Maruyama （1994） proposed the ＂plume tectonics＂ theory based on whole-mantle seismic tomogra- phy image （Fukao, 1992; Fukao et al., 1994）. According to this the- ory, the earth＇s interior is divided into three regimes： the earth＇s surface region governed by lateral motions of tectonic plates, the mantle governed by vertical motions of ＂superplumes＂（i.e., large- scale mantle upwelling/downwelling plumes）, and the core, whose convection style is probably controlled by superplumes in the mantle. With the rapid progress in earth science after the birth of the plume tectonics theory, it is now widely accepted that various geological phenomena observed in the earth＇s surface are closely linked to the fluid motion in the deep mantle （e.g., Davies, 2011）.

关键词： Plate and plume tectonics UHT deep LVL

TEXT CLASSIFICATION TOWARD A SCIENTIFIC FORUM

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Journal of Systems Science and Systems Engineering 2007年第3期16卷 356-369页

作者： Wen ZHANG Xijin TANG Taketoshi yoshida School of Knowledge Science Japan Advanced Institute of Science and Technology 1-1 Ashahidai Tatsunokuchi lshikawa 923-1292 Japan Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 P.R. China

Text mining, also known as discovering knowledge from the text, which has emerged as a possible solution for the current information explosion, refers to the process of extracting non-trivial and useful patterns from unstructured text. Among the general tasks of text mining such as text clustering, summarization, etc, text classification is a subtask of intelligent information processing, which employs unsupervised learning to construct a classifier from training text by which to predict the class of unlabeled text. Because of its simplicity and objectivity in performance evaluation, text classification was usually used as a standard tool to determine the advantage or weakness of a text processing method, such as text representation, text feature selection, etc. In this paper, text classification is carried out to classify the Web documents collected from XSSC Website （http：//***）. The performance of support vector machine （SVM） and back propagation neural network （BPNN） is compared on this task. Specifically, binary text classification and multi-class text classification were conducted on the XSSC documents. Moreover, the classification results of both methods are combined to improve the accuracy of classification. An experiment is conducted to show that BPNN can compete with SVM in binary text classification; but for multi-class text classification, SVM performs much better. Furthermore, the classification is improved in both binary and multi-class with the combined method.

关键词： Text classification SVM BPNN Xiangshan Science Conference

A 2-D mesoscopic model for the evaluation of creep damage induced by void growth in polycrystalline metals

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Acta Metallurgica Sinica(English Letters) 2011年第3期24卷 213-219页

作者： Tao YU Kimiaki yoshida Huiji SHI Key Laboratory of Applied Mechanics Department of Engineering Mechanics Tsinghua University Beijing 100084 China v Research Laboratory Ishikawajima-Harima Heary Industries Co. Ltd. Tokyo Japan

At elevated temperature, creep failures of polycrystalline metals after long-term constant loading are often caused by the nucleation, growth and coalescence of creep voids on the grain boundaries. Void h＇action is an important parameter for the evaluation of creep damage level of structural materials operating at high temperature. In this paper, a 2-D numerical simulation method was developed for analyzing the void fraction evolution during the process of creep, based on some hypothesis from experiments. The model was implemented and then was used to predict the evolution of void fraction in the 2.25Cr-1Mo steel of uniaxial creep experiment at 570 ℃, in which the simulation results showed good agreement with the experimental results.

关键词： Creep damage Grain boundary Void fraction Voronoi tessellation

TESTING k-EDGE-CONNECTIVITY OF DIGRAPHS

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Journal of Systems Science & Complexity 2010年第1期23卷 91-101页

作者： Yuichi yoshida.HiroI TO School of Informatics Kyoto University

This paper presents an algorithm that tests whether a given degree-bounded digraph is k-edge-connected or E-far from k-edge-connectivity. This is the first testing algorithm for k-edge- connectivity of digraphs whose running time is independent of the number of vertices and edges. A digraph of n vertices with degree bound d is ε-far from k-edge-connectivity if at least εdn edges have to be added or deleted to make the digraph k-edge-connected, preserving the degree bound. Given a constant error parameter ε and a degree bound d, our algorithm always accepts all k-edge-connected digraphs and reiects all digraphs that is ε-far from k-edge-connectivity with orobabilitv at least 2/*** runs in O（d（εd^-c）^k logεd^-1O）（c〉1 is a constant）time when input digraphs are restricted to be （k-1）-edge connected and runs in O（d（εd^-ck）^klogεd^-kO）（c〉1 is a constant）time for general digraphs.

关键词： Digraph graph k-edge-connectivity property testing.

Voyage of the Indian subcontinent since Pangea breakup and driving force of supercontinent cycles: Insights on dynamics from numerical modeling

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Geoscience Frontiers 2018年第5期9卷 1279-1292页

作者： Masaki yoshida M.Santosh Department of Deep Earth Structure and Dynamics Research Japan Agency for Marinee Earth Science and Technology (JAMSTEC) School of Earth Sciences and Resources China University of Geosciences Department of Earth Sciences School of Physical Sciences University of Adelaide Faculty of Science Kochi University

Recent advances in three-dimensional numerical simulations of mantle convection have aided in approximately reproducing continental movement since the Pangea breakup at 200 Ma. These have also led to a better understanding of the thermal and mechanical coupling between mantle convection and surface plate motion and predictions of the configuration of the next supercontinent. The simulations of mantle convection from 200 Ma to the present reveals that the development of large-scale cold mantle downwellings in the North Tethys Ocean at the earlier stage of the Pangea breakup triggered the northward movement of the Indian subcontinent. The model of high temperature anomaly region beneath Pangea resulting from the thermal insulation effect support the breakup of Pangea in the real Earth time scale, as also suggested in previous geological and geodynamic models. However, considering the low radioactive heat generation rate of the depleted upper mantle, the high temperature anomaly region might have been generated by upwelling plumes with contribution of deep subducted TTG(tonalite-trondhjemite-granite) materials enriched in radiogenic elements. Integrating the numerical results of mantle convection from 200 Ma to the present, and from the present to the future, it is considered that the mantle drag force acting on the base of continents may be comparable to the slab pull force, which implies that convection in the shallower part of the mantle is strongly coupled with surface plate motion.

关键词： Numerical modeling Plate tectonics Supercontinent Geodynamics Indian subcontinent Pangea

Manipulation of Micro Solid Particles and Induced Flows in Water by Laser Irradiation

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Journal of Thermal Science 2007年第2期16卷 176-180页

作者： Masahiro OTA Hiroshi OKANO Makoto yoshida Division of Mechanical Engineering Tokyo Metropolitan University1Minami-osawaHachi-ojiTokyo 192-0397Japan

Q-switch for pulsing laser beam and Galvano scanner for rapid scanning laser beam were adapted to manipulate micro solid particles in a water droplet. The trapping of fine particles at micron-sized diameters by a YAG laser system, induced flows, and the induced motion of the particles by laser beam irradiations are discussed. Particle rotations are observed by using anisotropic micro objects, and moreover the rotational rate with clockwise direction is 22 r/min. The fragments of a cover glass were mixed in a water droplet, and their size and shape are uneven. The rotation of that non-spheres without scanning by the Galvano scanner is also observed in water.

关键词： Laser trapping non-sphere particle optical radiation pressure laser scanning laser drive rotation

Evaluation of interfacial strength by an instrumented indentation method and its application to an actual TBC vane

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Acta Metallurgica Sinica(English Letters) 2011年第2期24卷 109-117页

作者： Yasuhiro YAMAZAKI Shin-ichiro KUGA Toshihiko yoshida Department of Mechanical and Control Engineering Department of Advanced Production Systems Engineering Niigata Institute of Technology Graduate School Ryodensya Co.

The thermal fatigue behaviour of an air plasma sprayed thermal barrier coating was investigated. And also the interfacial strengths of thermal barrier coated specimens subjected to thermal fatigue, as well as a retired TBC vane were also evaluated by means of an instrumented indentation machine. The results indicated that, （1） the TGO grew at the interface during thermal fatigue cycle as a function of the exposure time at elevated temperature; （2） the microcracks were initiated in the top coating and at the interface after thermal cycle tests; （3） the interfacial strength of TBC, which was evaluated by the indentation method, increased with the thermal cycles; （4） the interfacial strength of the retired TBC vane was almost equal with that of the as-sprayed TBC specimen.

关键词： Thermal barrier coating Interfacial fracture toughness Indentation method

Selection of appropriate endoscopic therapies for duodenal tumors: An open-label study, single-center experience

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World Journal of Gastroenterology 2014年第26期20卷 8624-8630页

作者： Satohiro Matsumoto Yukio yoshida Department of Gastroenterology Saitama Medical CenterJichi Medical University

AIM: To determine an appropriate compartmentalization of endoscopic submucosal dissection (ESD) or endoscopic mucosal resection (EMR) for duodenal tumors.

关键词： Duodenal tumor Endoscopic submucosal dissection Endoscopic mucosal resection Cancer Adenoma Neuroendocrine tumor

Requirements for implementation of artificial intelligence in the practice of gastrointestinal pathology

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World Journal of Gastroenterology 2021年第21期27卷 2818-2833页

作者： Hiroshi yoshida Tomoharu Kiyuna Department of Diagnostic Pathology National Cancer Center HospitalTokyo 104-0045Japan Digital Healthcare Business Development Office NEC CorporationTokyo 108-8556Japan

Tremendous advances in artificial intelligence(AI)in medical image analysis have been achieved in recent *** integration of AI is expected to cause a revolution in various areas of medicine,including gastrointestinal(GI)***,deep learning algorithms have shown promising benefits in areas of diagnostic histopathology,such as tumor identification,classification,prognosis prediction,and biomarker/genetic alteration *** AI cannot substitute pathologists,carefully constructed AI applications may increase workforce productivity and diagnostic accuracy in pathology *** of these promising advances,unlike the areas of radiology or cardiology imaging,no histopathology-based AI application has been approved by a regulatory authority or for public ***,implying that there are still some obstacles to be overcome before AI applications can be safely and effectively implemented in real-life pathology *** challenges have been identified at different stages of the development process,such as needs identification,data curation,model development,validation,regulation,modification of daily workflow,and cost-effectiveness *** aim of this review is to present challenges in the process of AI development,validation,and regulation that should be overcome for its implementation in real-life GI pathology practice.

关键词： Artificial intelligence Deep learning Digital image analysis Digital pathology Clinical implementation Gastrointestinal cancer