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求解大规模矩阵问题的Krylov子空间方法

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南京航空航天大学学报 2001年第2期33卷 139-145页

作者：戴华南京航空航天大学理学院南京210016

求解大规模矩阵问题包括线性方程组和特征值问题等是计算数学和科学工程计算中的重大课题。最近几年 ,其研究工作取得了许多重大进展。文中给出大型线性方程组和特征值问题 Krylov子空间方法若干进展的一个概述 ,其中包括作者对这些问... 详细信息

求解大规模矩阵问题包括线性方程组和特征值问题等是计算数学和科学工程计算中的重大课题。最近几年 ,其研究工作取得了许多重大进展。文中给出大型线性方程组和特征值问题 Krylov子空间方法若干进展的一个概述 ,其中包括作者对这些问题的研究成果。涉及的专题包括求解大型线性方程组的共轭梯度法、SYMMLQ算法、MINRES算法、GMRES算法、Lanczos双正交化算法、QMR算法以及这些算法的块格式 ;求解大型对称特征值问题的 Lanczos算法和块 Lanczos算法 ;求解大型非对称特征值问题的 Lanczos算法、Arnoldi算法以及这些算法的块推广。讨论求解大规模矩阵问题的加速技术和预处理技术。

关键词：线性方程组特征值 Krylov子空间方法大规模矩阵

Measurements of the Differential Elastic and Inelastic Scattering Cross Sections of ^(12)C

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Chinese journal of nuclear physics 1995年第2期17卷 171-173页

作者： Zhang Kun Cao Jian-hua dai Yun-shen Wan dai-rong(Institute of Nuclear Science and Technology,Sichuan University,Chengdu 610064) 四川大学原子核科学技术所四川成都

The differential elastic and inelastic scattering neutron cross sections of 12C atEn=14.7 MeV produced by the T（d,n）4He reaction were measured using an associatedparticle fast neutron TOF spectrometer at 15 angles ranging from 15° to 130°.Theflight path was 2.54 *** neutron detector consisting of an ST-451 liquid scintillatorwas massively shielded.

关键词： Elastic scattering Inelastic Scattering Differential cross section

Pancreatic cancer with ovarian metastases: A case report and review of the literature

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World Journal of Clinical Cases 2020年第21期8卷 5380-5388页

作者： Shun-Da Wang Liang Zhu huan-Wen Wu Meng-hua dai Yu-Pei Zhao Department of General Surgery Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Radiology Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Pathology Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

BACKGROUND Pancreatic cancer with ovarian metastases is rare and easily *** patients are first diagnosed with ovarian *** report a rare case of ovarian metastases secondary to pancreatic *** also review the literature to analyze the clinical characteristics of,diagnostic methods for,and perioperative management strategies for this rare *** SUMMARY A 48-year-old woman with an abdominal mass presented to our *** tomography revealed lesions in the pancreas and lower *** examination and histological investigation of biopsy specimens revealed either an ovarian metastasis from a pancreatic neoplasm or two primary tumors,with metastasis strongly *** patient simultaneously underwent distal pancreatectomy plus splenectomy by a general surgeon and salpingo-oophorectomy with hysterectomy by a *** examination of the surgical specimen revealed a pancreatic adenocarcinoma(intermediate differentiation,mucinous)and a metastatic mucinous adenocarcinoma in the *** For this rare tumor,surgical resection is the most effective treatment,and the final diagnosis depends on tumor pathology.

关键词： Pancreas Ovary Pancreatic cancer Ovarian cancer Metastasis Case report

The Construction of a Learning-Oriented Speaking Assessment Model in College English Based on the Online Diagnostic Assessment

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Journal of Contemporary Educational Research 2024年第2期8卷 26-33页

作者： hua dai Prospect College Chongqing College of Mobile CommunicationChongqing 401120China

Since language is a tool for communication,proficiency in English communication is a fundamental necessity for talent in the 21st ***,surveys reveal that most college students at private colleges possess inadequate oral English skills,and what some have learned is“mute English.”Therefore,developing their English-speaking skills is another challenge faced by students attending private *** diagnostic assessment methods are growing globally with the use of *** diagnostic assessment system is one of the online English diagnostic assessment platforms currently being widely used in ***,the present work is conducted to investigate and conduct an oral English learning-oriented assessment model in college English using the online diagnostic *** the research result,it is hoped that the study could provide useful information for improving UDig system and make a better use of it in college oral English learning and teaching.

关键词： Oral English assessment Diagnostic assessment UDig system Learning-Oriented Assessment(LOA)

Isothermal Microcalorimetry:A Review of Applications in Soil and Environmental Sciences

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Pedosphere 2007年第2期17卷 137-145页

作者： RONG Xing-Min huaNG Qiao-Yun JIANG dai-hua CAI Peng LIANG Wei Key Laboratory of Subtropical Agricultural Resources and Environment Ministry of Agriculture Huazhong Agricultural University Wuhan 430070 （China）

Isothermal microcalorimetry provides thermodynamic and kinetic information on various reactions and processes and is thereby a powerful tool to elucidate their mechanisms. Certain improvement in isothermal microcalorimetry with regard to the studies on soil and environmental sciences is briefly described. This review mainly focuses on the use of microcalorimetry in the determination of soil microbial activity, monitoring the toxicity and biodegradation of soil organic pollutants, the risk evaluation of metals and metalloids, the heat effect of ion exchange and adsorption in soil, and environmental researches. Promising prospects for the applications of the technique in the field are also discussed.

关键词： environment isothermal microbial activity microcalorimetry soil

Synthesis and Crystal Structure of a Novel Manganese Coordination Polymer: 2,5-Bis(4-pyridyl)-3,4-diaza-2,4-hexadiene

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Chinese Journal of Structural Chemistry 2007年第2期26卷 219-223页

作者： CHEN Man-Sheng DENG Yi-Fang ZHANG Chun-hua KUANG dai-Zhi FENG Yong-Lan PENG Yun-Lin Department of Chemistry and Materials Science Hen gyan g Normal University Hen gyan g 421008 China

A new manganese coordination polymer 1, [Mn（H2O）4（L）]n（ClO4）2n.2nH2O.3nL （L = 2,5-bis（4-pyridyl）-3,4-diaza-2,4-hexadiene）, has been synthesized and structurally characterized. The crystal structure was determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group Pn with a = 13.9176（8）, b = 15.4754（9）, c = 15.9670（9） A, β = 99.5010（10）°, V = 3391.8（3） ]k3, Z = 2, C56H68C12MnN16O14, Mr= 1315.10, Dc = 1.288 g/cm^3,μ = 0.344 mm^-1, F（000） = 1374, R = 0.0733 and wR = 0.2035. In the crystal the manganese atom is six-coordinated by two nitrogen atoms from 2,5-bis（4-pyridyl）-3,4-diaza-2,4-hexadiene and four oxygen atoms from water molecules, completing an octahedral geometry. The title complex exhibits a novel supramolecular layer architecture sustained by the concurrence of coordination bonds, hydrogen bonds, and π-π stacking interactions.

关键词： manganese complex Schiff bases crystal structure

Type 2 epithelial mesenchymal transition in vivo： truth or pitfalls？

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Chinese Medical Journal 2012年第18期125卷 3312-3317页

作者： XU Xue-feng dai hua-ping Beijing Key Laboratory of Respiratory and Pulmonary Circulation Beijing Institute of Respiratory Medicine Faculty of RespiratoryMedicine Capital Medical University Department of Respiratoryand Critical Care Medicine Beijing Chao-Yang Hospital CapitalMedical University China Beijing 100020

Epithelial-mesenchymal transition （EMT） is a process by which fully differentiated epithelial cells undergo a phenotypic conversion and assume a mesenchymal cell phenotype, including elongated morphology, enhanced migratory and invasiveness capacity, and greatly increased production of extracellular matrix （ECM） components. The EMTs associated with wound healing, tissue regeneration, and organ fibrosis are termed as type 2 EMT. Over the past two decades, emerging evidence suggested that injured epithelial cells, via type 2 EMT, may serve as important sources of fibroblasts and contribute to organ fibrosis, such as kidney, liver, lung and eyes. There is perhaps no doubt that adult epithelial cells can undergo EMT in vitro in response to transforming growth factor （TGF）-131 and other inflammatory or pro-fibrotic stimuli. However, whether type 2 EMT really occurs in vivo, whethers it is actually a source of functional and activated interstitial fibroblasts and whether it contributes to tissue fibrosis have already been the subjects of heated debate. In this review, we will describe the main features of EMT, the major findings of type 2 EMT in vitro, the evidences for and against type 2 EMT in vivo and discuss the heterogeneity and pitfalls of the techniques used to detect EMT during fibrotic diseases. We suggest that in order to ascertain the existence of type 2 EMT in vivo, different proper phenotype markers of epithelial and mesenchymal cells should be jointly used and cell lineage tracking techniques should be standardized and avoid false positives. Finally, we believe that if EMT really occurs and contributes to tissue fibrosis, efforts should be made to block or reverse EMT to attenuate fibrotic process.

关键词： epithelial mesenchymal transition tissue fibrosis fibroblast

Rapamycin in fibrotic diseases： beneficial or detrimental agent？

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Chinese Medical Journal 2013年第7期126卷 1364-1369页

作者： XU Xue-feng dai hua-ping Department of Respiratory and Critical Care Medicine Beijing Chao-Yang Hospital Capital Medical University Beijing 100020 China Beijing Key Laboratory of Respiratory and Pulmonary Circulation Disorders Beijing Institute of Respiratory Medicine Beijing 100020 China

apamvcin was first isolated from a strain of Sreptomyces hygroscopicus in the early 1970s froma soil sample taken on Easter Island. Because the antiproliferative effects of rapamycin on yeast cell, as well as B and T lymphocytes, it was first identified as an antimicrobial agent with potent immunosuppressive activity and has been used in antirejection therapy.

关键词： fibrotic disease rapamycin mammalian target of rapaymycin negative feedback loop antifibrogenesis

Proximal Point-Like Method for Updating Simultaneously Mass and Stiffness Matrices of Finite Element Model

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Transactions of Nanjing University of Aeronautics and Astronautics 2020年第1期37卷 1-12页

作者： dai hua WANG Kangkang College of Science Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China

The problem of correcting simultaneously mass and stiffness matrices of finite element model of undamped structural systems using vibration tests is considered in this *** desired matrix properties,including satisfaction of the characteristic equation,symmetry,positive semidefiniteness and sparsity,are imposed as side constraints to form the optimal matrix pencil approximation *** partial Lagrangian multipliers,we transform the nonlinearly constrained optimization problem into an equivalent matrix linear variational inequality,develop a proximal point-like method for solving the matrix linear variational inequality,and analyze its global *** results are included to illustrate the performance and application of the proposed method.

关键词： model updating proximal point method optimal matrix pencil approximation matrix linear variational inequality