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Multirange Fractal Analysis on the Negative Correlation between Fractal Dimension of Fractured Surface and Toughness of Materials

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Journal of Materials Science & Technology 1996年第4期12卷 318-320页

作者： Lung, CW Jiang, ja Zhang, CH International Centre for Materials Physics Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

Applying the concept of multirange fractals, a new explanation to the Williford's multifractal curve on the relationship of fractal dimension with fracture properties in materials has been given. It shows the importance of factorizing out the effect of fractal structure from other physical causes and separating the appropriate range of scale from multirange fractals.

关键词： Fracture

Iksan526 Rice Callus Extract Induces Dedifferentiation of Rabbit Articular Chondrocytes via ERK1/2 and PI-3K/Akt Pathways

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Rice science 2020年第6期27卷 504-514页

作者： Seong-Hui EO Song ja Kim Department of Biological Sciences College of Natural SciencesKongju National UniversityGongju 32588Republic of Korea

The resveratrol-enriched transgenic rice line Iksan526(IS526),first developed by the Rural Development Administration of Korea using genetic engineering techniques,shows beneficial health effects in mitigating metabolic syndrome and ***,the effects of IS526 on the differentiation of chondrocytes and the underlying mechanism have not been investigated in *** this study,the effects and cellular regulatory mechanisms of IS526 on rabbit articular chondrocytes were *** IS526 callus extract treatment,the expression levels of differentiation-related proteins were detected via western blotting,Alcian blue staining and immune-luorescence ***526 decreased the type Ⅱ collagen and proteoglycan levels in dose-and time-dependent *** further analyzed the effects of IS526 on skeleton genesis in zebrafish larvae using Alcian blue staining,which showed a reduction in cartilage formation along with increased production of matrix metalloproteinase(MMP)-***526 also increased the phosphorylation of ERK1/2 and p38 kinase but inhibited the phosphorylation of *** inhibition of MMP-13 blocked the IS526-induced decrease in type Ⅱ collagen *** of p38 kinase or PI-3K/Akt with SB203580 and LY294002 enhanced the suppression of type Ⅱ collagen,but the blockage of ERK-1/2 by PD98059 rescued IS526-induced *** results suggested that IS526 regulates type Ⅱ collagen and MMP-13 expression via the ERK1/2 and PI-3K/Akt pathways in rabbit articular chondrocytes.

关键词： rice chondrocyte typeⅡcollagen matrix metalloproteinase-13 rice callus extract

Snowstorm over the Southwestern Coast of the Korean Peninsula Associated with the Development of Mesocyclone over the Yellow Sea

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Advances in Atmospheric Sciences 2008年第5期25卷 765-777页

作者： Ki-Young HEO Kyung-ja HA Division of Earth Environmental System College of Natural Sciences Pusan National University Korea

This study investigates the characteristics of a heavy snowfall event over the southwestern part of the Korean Peninsula on 4 December 2005. The snowstorm was a type of mesoscale maritime cyclone which resulted from barotropic instability, and diabatic heating from the warm ocean in continental polar air masses. Based on surface observations, radiosonde soundings, MTSAT-1R satellite data and the 10-km grid RDAPS （Regional Assimilation and Prediction System based on the PSU/NCAR MM5） data, the evolution of the mesocyclone is explained by the following dynamics; （1） In the initial stage, the primary role in the cyclogenesis process of the mesocyclone is a barotropic instability in the horizontal shear zone. （2） In the developing stage, the mesocyclone moves and deepens into a baroclinic zone corresponding to the surface heating and moistening. （3） In the mature stage, it is found that the mesocyclone is intensified by the destabilization caused by enhanced low-level heating and condensation, the moisture flux convergence, and the interaction between upper and lower-level potential vorticity anomalies. We suggest that a checklist with stepwise indicators responsible for development be prepared for the forecasting of heavy snowfall over the southwestern part of the Korean Peninsula.

关键词： heavy snowfall mesocyclone baroclinic instability barotropic instability stepwise roles potential vorticity anomalies

Esophageal resection for high-grade dysplasia and intramucosal carcinoma: When and how?

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World Journal of Gastroenterology 2010年第30期16卷 3786-3792页

作者： Vani ja Konda Mark K Ferguson Department of Medicine The University of Chicago Pritzker School of MedicineChicagoIL 60637United States Department of Surgery The University of Chicago Pritzker School of MedicineChicagoIL 60637United States

High-grade dysplasia (HGD) and intramucosal carcinoma (IMC) in the setting of Barrett’s esophagus have traditionally been treated with esophagectomy. However, with the advent of endoscopic mucosal resection and endoscopic ablative therapies, endoscopic therapy at centers with expertise is now an established treatment of Barrett’s-esophagus-related neoplasia, including HGD and IMC. Esophagectomy is today reserved for more selected cases with submucosal invasion, evidence for lymph node metastasis, or unsuccessful endoscopic therapy.

关键词： Barrett’s esophagus High-grade dysplasia Intramucosal carcinoma Endoscopic mucosal resection Esophagectomy

Implementation of Turbulent Mixing over a Stratocumulus-Topped Boundary Layer and Its Impact in a GCM

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Advances in Atmospheric Sciences 2009年第5期26卷 995-1004页

作者： Sun-Hee SHIN Kyung-ja HA Division of Earth Environmental System Pusan National University

The effect of a vertical diffusion scheme over a stratocumulus topped boundary layer （STBL） was investigated using the YONU AGCM （Yonsei University Atmospheric General Circulation Model）. To consider the impact of clouds on the turbulence production, the turbulence mixing term, driven by radiative cooling at the cloud top, is implemented as an extended non-local diffusion scheme. In the model with this new scheme, the STBL parameterization significantly influences the lower atmosphere over the tropical and subtropical regions. Consideration of the turbulent mixing within the cloud layer leads to continuous stratocumulus formation. The cloud-top radiative cooling tends to favor more rapid entrainment and produces top-down turbulent mixing. This cooling develops a mixed layer without initiation of deep convection by surface fluxes. Variations in thermodynamical and dynamical features are produced by planetary boundary layer （PBL） cloud development. The simulated stratocumulus induces more mixing of heat and moisture due to the cloud forcing. Over STBL regions, the lower boundary layer becomes warmer and drier. It also weakens vertical motion and zonal trade winds in the eastern Pacific, which indicates that stratocumulus cloud cover plays a role in weakening the Walker circulation; that is, cloud cover damps the tropical circulation.

关键词： stratocumulus topped boundary layer non-local diffusion scheme tropical circulation general circulation model

An accelerated K-means clustering algorithm using selection and erasure rules

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第10期13卷 761-768页

作者： Suiang-Shyan LEE ja-Chen LIN Department of Computer Science National Chiao Tung University

The K-means method is a well-known clustering algorithm with an extensive range of applications,such as biological classification,disease analysis,data mining,and image ***,the plain K-means method is not fast when the number of clusters or the number of data points becomes large.A modified K-means algorithm was presented by Fahim et al.(2006).The modified algorithm produced clusters whose mean square error was very similar to that of the plain K-means,but the execution time was *** this study,we try to further increase its *** are two rules in our method:a selection rule,used to acquire a good candidate as the initial center to be checked,and an erasure rule,used to delete one or many unqualified centers each time a specified condition is *** clustering results are identical to those of Fahim et al.(2006).However,our method further cuts computation time when the number of clusters *** mathematical reasoning used in our design is included.

关键词： K-means clustering Acceleration Vector quantization Selection Erasure

ON TRANSMISSION PROBLEM FOR VISCOELASTIC WAVE EQUATION WITH A LOCALIZED A NONLINEAR DISSIPATION

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Acta Mathematica Scientia 2013年第2期33卷 362-374页

作者： Jeong ja BAE Seong Sik KIM Department of Mathematics Dongeui UniversityPusan 614-714Korea

In this article, we consider the global existence and decay rates of solutions for the transmission problem of Kirchhoff type wave equations consisting of two physically different types of materials, one component being a Kirchhoff type wave equation with time dependent localized dissipation which is effective only on a neighborhood of certain part of boundary, while the other being a Kirchhoff type viscoelastic wave equation with nonlinear memory

关键词： Existence of solution uniform decay transmission problem boundary valueproblem localized dissipation

Spectrum and Singular Integrals on a New Weighted Function Space

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Acta Mathematica Sinica,English Series 2018年第11期34卷 1692-1702页

作者： Hee Chul PAK Young ja PARK Department of Mathematics Dankook University Dandae-ro 119 Dongnam-gu Cheonan-si Chungnam 31116 Republic of Korea Department of Mathematics Hoseo University Hoeo-ro 79 Asan-si Chungnam 31499 Republic of Korea

We introduce a new function space that is much finer than the classical Lebesgue spaces, and investigate the continuity and the discontinuity of the Calderon-Zygmund operators on the new weighted spaces. In order to identify the continuity of singular integrals, we prove an interpolation theorem on the new spaces and propose a concept of the spectrum of base functions.

关键词： Function spaces singular integrals interpolation Calderdn Zygmund operators Holder's inequality L log L

Improved block matching approach to fast disparity estimation

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1278-1285页

作者： Tao Tangfei ja Choon Koo Hyouk Ryeol Choi School of Mechanical Engineering Xi'an Jiaotong Univ. Xi'an 710049 P. R. China State Key Lab. for Manufacturing Systems Engineering Xi'an 710049 P. R. China School of Mechanical Engineering Sungkyunkwan Univ. Suwon Republic of Korea

An improved block matching approach to fast disparity estimation in machine vision applications is proposed, where the matching criterion is the sum of the absolute difference（SAD）.By evaluating the lower bounds, which become increasingly tighter for the matching criteria, the method tries to successively terminate unnecessary computations of the matching criteria between the reference block in one image and the ineligible candidate blocks in another *** also eliminates the ineligible blocks as early as possible, while ensuring the optimal disparity of each ***, the proposed method can further speed up the elimination of ineligible candidate blocks by efficiently using the continuous constraint of disparity to predict the initial disparity of each *** performance of the new algorithm is evaluated by carrying out a theoretical analysis, and by comparing its performance with the disparity estimation method based on the standard block *** results demonstrate that the proposed algorithm achieves a computational cost reduction of over 50.5% in comparision with the standard block matching method.

关键词： machine vision block matching disparity estimation sum of the absolute difference.