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New Type of Basic Functions of FEM in Application to Solution of Inverse Heat Conduction Problem

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Journal of Thermal Science 2002年第2期11卷 163-171页

作者： michaelj.CIALKOWSKI TU Poznan Poland

The work presents the application of heat polynomials for solving an inverse problem. The heat polynomials form the Treffetz Method for non-stationary heat conduction problem. They have been used as base functions in Finite Element Method. Application of heat polynomials permits to reduce the order of numerical integration as compared to the classical Finite Element Method with formulation of the matrix of system of equations.

关键词： non-stationary heat conduction problem Treffetz method FEM new basic function.

A Mathematical Model and Simulations of Low Temperature Nitriding Katarzyna Tkacz-Smiech *** dedicate this article to the memory of Professor Katarzyna Tkacz-Smiech

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Computer Modeling in Engineering & Sciences 2022年第2期130卷 777-803页

作者： Bogusław Bo˙zek Lucjan Sapa Katarzyna Tkacz-Smiech Marek Danielewski Janusz rybak AGH University of Science and Technology Faculty of Applied MathematicsCracow30-059Poland AGH University of Science and Technology Faculty of Materials Science and CeramicsCracow30-059Poland

Low-temperature nitriding of steel or iron can produce an expanded austenite phase,which is a solid solution of a large amount of nitrogen dissolved interstitially in fcc *** is characteristic that the nitogen depth profiles in expanded austenite exhibit plateau-type *** behavior cannot be considered with a standard analytic solution for diffusion in a semi-infinite solid and a new approach is *** formulate a model of interdiffusion in viscoelastic solid(Maxwellmodel)during the nitriding *** combines themass conservation and Vegard’s rule with the Darken bi-velocity *** model is formulated in any dimension,i.e.,a mixture is included in R^(n),n=1,2,*** the system in one dimension,n=1,we transform a differential-algebraic system of 5 equations to a differential system of 2 equations only,which is better to study numerically and *** modification allows the formulation of effective mixed-type boundary *** resulting nonlinear strongly coupled parabolic-elliptic differential initial-boundary Stefan type problem is solved numerically and a series of simulations is made.

关键词： Nitriding expanded austenite Maxwell solid Darken method Vegard rule

Solution of the Stationary 2D Inverse Heat Conduction Problem by Treffetz Method

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Journal of Thermal Science 2002年第2期11卷 148-162页

作者： michaelj.CIALKOWSKI AndrzejFRACKOWIAK Poznan University of Technology Poland

The paper presents analysis of a solution of Laplace equation with the use of FEM harmonic basic functions. The essence of the problem is aimed at presenting an approximate solution based on possibly large finite element. Introduction of harmonic functions allows to reduce the order of numerical integration as compared to a classical Finite Element Method. Numerical calculations conform good efficiency of the use of basic harmonic functions for resolving direct and inverse problems of stationary heat *** part of the paper shows the use of basic harmonic functions for solving Poisson’s equation and for drawing up a complete system of biharmonic and polyharmonic basic

关键词： Treffetz method stationary heat conduction FEM harmonic basic functions.

A New Symmetrodont Mammal with Fur Impressions from the Mesozoic of China

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 7-14页

作者： GuillermoW.ROUGIER michaelj.NOVACEK Department of Anatomical Sciences and Neurobiology University of Louisville Louisville KY 40292USADivision of Paleontology American Muscum of Natural History Central Park West at 79th StreetNew York NY 10024-5192 USA

Western Liaoning of northeastern China is world-renowned for the MesozoicJehol biota, especially for yielding many feathered dinosaurs, primitive birds, mammals and fossilangiosperm. This paper describes a complete specimen of a symmetrodont mammal with well-preservedhairs and soft tissue from the basal part of the Yixian Formation in the Sihetun area, Beipiao,western Liaoning. It is significant for understanding the morphology, osteology, phylogeny and lifehabits of Mesozoic symmetrodont mammals.

关键词： symmetrodont mammals Yixian Formation western Liaoning China

Forecasting Helicoverpa populations in Australia： A comparison of regression based models and a bioclimatic based modelling approach

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Insect Science 2005年第1期12卷 45-56页

作者： MYRONP.ZALUCKI michaelj.FURLONG SchoolofIntegrativeBiology TheUniversityofQueenslandStLuciaBrisbaneQueensland4072Australia

Long-term forecasts of pest pressure are central to the effective management of many agricultural insect pests. In the eastern cropping regions of Australia, serious infestations of Helicoverpa punctigera (Wallenglen) and H. armigera (Hübner)(Lepidoptera:Noctuidae) are experienced annually. Regression analyses of a long series of light-trap catches of adult moths were used to describe the seasonal dynamics of both species. The size of the spring generation in eastern cropping zones could be related to rainfall in putative source areas in inland Australia. Subsequent generations could be related to the abundance of various crops in agricultural areas, rainfall and the magnitude of the spring population peak. As rainfall figured prominently as a predictor variable, and can itself be predicted using the Southern Oscillation Index (SOI), trap catches were also related to this variable. The geographic distribution of each species was modelled in relation to climate and CLIMEX was used to predict temporal variation in abundance at given putative source sites in inland Australia using historical meteorological data. These predictions were then correlated with subsequent pest abundance data in a major cropping region. The regression-based and bioclimatic-based approaches to predicting pest abundance are compared and their utility in predicting and interpreting pest dynamics are discussed.

关键词：澳大利亚种群数量预测方法生物气候学迁移 Helicoverpa 害虫防治种群地理分布

The role of B-type natriuretic peptide in the diagnosis and treatment of decompensated heart failure

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Journal of Geriatric Cardiology 2004年第1期1卷 21-28页

作者： michaelj.Gallagher PeterA.McCullough Divisions of Cardiology Nutrition and Preventive MedicineWilliam Beaumont HospitalRoyal OakMI 48073USA

Heart failure (HF) is a common disease associated with increasing age. B-type natriuretic peptide (BNP), is a cardiac neurohormone, and is released as prepro BNP and then enzyrnatically cleaved to the Ntenninal-proBNP (NT-proBNP) and BNP upon ventricular myocyte stretch. Blood measurements of BNP have been used to identify patients with I-IF. The BNP assay is currently used as a diagnostic and prognostic aid in HF. In general, a BNP level below 100 pg/mL excludes acutely decompensated HF and levels ＞ 500 pg/ml indicate decompensation. Recombinant human BNP (hBNP, nesiritide) is an approved intravenous treatment for acute,decompensated -HF. Nesiritide given in supraphysiologic doses causes vasodilation, natriuresis, diuresis, and improved symptoms over the course of a 48-hour infusion. This paper will sort out the literature concerning the use of this peptide both as a diagnostic test and as an intravenous therapy.

关键词： BNP The role of B-type natriuretic peptide in the diagnosis and treatment of decompensated heart failure type

EFFECT OF THE RATION Th/U ON TL DATING ACCURACY

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Nuclear Science and Techniques 1994年第2期5卷 87-92页

作者：梁宝鎏 michaelj.Stokes 等 DepartmentofPhysicsandMaterialsScience CityPolytechnicofHongKong

In routine thermoluminescence(TL) dating,there is often a tendency to omit an absolute determination of the thorium and uranium content in the sample and simply measure the total alpha count *** annual dose is then calculated assuming equal activities for a Th/U weight ratio of about 3.17. In fact this ratio is varied significantly in *** of the annual dose conversion factors from data using the total alpha count rate in a selected range of Th/U weight ratios shows significant *** results indicate that the additional error contribution to the final TL age is in the range ±2.5%to±4.1% for most cases where the Th/U ratio lies between 1.1 and 9.5.

关键词：铀含量钍含量样品热致发光年代断定

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清醒山羊颈动脉体灌流模型及其评估

生理学报 1993年第2期45卷 200-205页

作者：钮伟真 michaelj.A.EngwallGeraldE.Bisgard 首都医学院心血管生理研究北京100054 美国威斯康新大学比较生物学系

本文对清醒山羊颈动脉体灌流模型作了详细介绍。手术步骤包括:(1)在颈部任一侧结扎枕动脉、切断窦神经及切除颈动脉体;(2)完成对供应另一侧(灌流侧)脑和颈部血管的改道手术,以便从血液供应上游离颈动脉体;(3)在灌流侧安置颈静脉插管和... 详细信息

本文对清醒山羊颈动脉体灌流模型作了详细介绍。手术步骤包括:(1)在颈部任一侧结扎枕动脉、切断窦神经及切除颈动脉体;(2)完成对供应另一侧(灌流侧)脑和颈部血管的改道手术,以便从血液供应上游离颈动脉体;(3)在灌流侧安置颈静脉插管和颈动脉插管,建立灌流通路。实验中应用体外循环方法以动物自身血液灌流颈动脉体。该模型具有两个显著优点:(1)实验中可保持动物处于正常生理状态;(2)对脑组织和颈动脉体的血液血气及pH能分别加以人为控制。实验前动物均经过氰化钠试验检查颈动脉体和主动脉体的化学敏感性,用以评价灌流模型的有效性。文中还对这一模型的应用进行了讨论。

关键词：颈动脉体山羊动物模型

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Energy for China

China Oil & Gas 2002年第3期9卷 21-23页

作者： michaelj.Economides University of Houston in the United States

Rarely has the world witnessed the breathtaking economic developments currently ongoing in China. Neither the explosive entry in the international scene by the fresh nation of the United States, following World War Ⅰ, nor the reconstruction frenzy of post-World War Ⅱ Europe and Japan can rival the growth of China in the last decade and the even more intense one expected in the future.

关键词： GDP Energy for China World