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An Optimized Perfectly Matched Layer for the Schrödinger Equation

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Communications in Computational Physics 2011年第1期9卷 147-179页

作者： Anna Nissen Gunilla kreiss Department of Information Technology Uppsala UniversityP.O.Box 337SE-75105 UppsalaSweden.

We derive a perfectly matched layer(PML)for the Schrödinger equation using a modal *** derive approximate error formulas for the modeling error from the outer boundary of the PML and the error from the discretization in the layer and show how to choose layer parameters so that these errors are matched and optimal performance of the PML is *** computations in 1D and 2D demonstrate that the optimized PML works efficiently at a prescribed accuracy for the zero potential case,with a layer of width less than a third of the de Broglie wavelength corresponding to the dominating frequency.

关键词： Schrödinger equation perfectly matched layer

Resolvent Estimates and Quantification of Nonlinear Stability

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Acta Mathematica Sinica,English Series 2000年第1期16卷 1-20页

作者： Heinz-Otto kreiss Jens Lorenz Department of Mathematics UCLALos AngelesCA 90095USA Department of Mathematics and Statistics UNMAlbuquerqueNM 87131USA

The aim of this paper is to clarify the role played by resolvent estimates for nonlinear *** will give examples showing that a large resolvent may lead to a small domain of nonlinear *** other examples the resolvent is large,but the domain of nonlinear stability is completely *** case prevails depends on the details of the problem. We will also show that the size of the resolvent depends in an essential way on the norms that are used.

关键词： Resolvent estimates Nonlinear stability Pseudospectrum Convection-dominated flow

A Well-Posed and Discretely Stable Perfectly Matched Layer for Elastic Wave Equations in Second Order Formulation

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Communications in Computational Physics 2012年第5期11卷 1643-1672页

作者： Kenneth Duru Gunilla kreiss Division of Scientific Computing Department of Information TechnologyUppsala UniversityBox 337SE-75105 UppsalaSweden

We present a well-posed and discretely stable perfectly matched layer for the anisotropic(and isotropic)elastic wave equations without first re-writing the governing equations as a first order *** new model is derived by the complex coordinate stretching *** standard perturbation methods we show that complex frequency shift together with a chosen real scaling factor ensures the decay of eigen-modes for all relevant *** buttress the stability properties and the robustness of the proposed model,numerical experiments are presented for anisotropic elastic wave *** model is approximated with a stable node-centered finite difference scheme that is second order accurate both in time and space.

关键词： Perfectly matched layer well-posedness stability hyperbolicity elastic waves

Coupling of Gaussian Beam and Finite Difference Solvers for Semiclassical Schrodinger Equations

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Advances in Applied Mathematics and Mechanics 2015年第6期7卷 687-714页

作者： Emil Kieri Gunilla kreiss Olof Runborg Division of Scientific Computing Department of Information TechnologyUppsala UniversitySweden Department of Mathematics and Swedish e-Science Research Center(SeRC) KTHSweden

In the semiclassical regime,solutions to the time-dependent Schrodinger equation for molecular dynamics are highly *** number of grid points required for resolving the oscillations may become very large even for simple model problems,making solution on a grid *** methods like Gaussian beams can resolve the oscillations with little effort and yield good approximations when the atomic nuclei are heavy and the potential is ***,when the potential has variations on a small length-scale,quantum phenomena become *** asymptotic methods are less *** two classes of methods perform well in different parameter *** opens for hybrid methods,using Gaussian beams where we can and finite differences where we have *** propose a new method for treating the coupling between the finite difference method and Gaussian *** new method reduces the needed amount of overlap regions considerably compared to previous methods,which improves the efficiency.

关键词： Gaussian beams semiclassical Schrodinger equation hybrid methods

Relative longevity among retired military personnel: an historical-cohort study

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Military Medical Research 2015年第3期3卷 133-138页

作者： Michael Hartal Yitshak kreiss Nirit Yavnai Israel Defense Forces Medical Corps Military PO Box 02149 Tel Hashomer Israel Department of Military Medicine Hebrew University Faculty of Medicine

Background: Occupation is a significant factor in life, health and well-being. Long-term military service is a unique career path that may influence life expectancy, even after excluding obvious risks such as battlefield mortality. However, it remains unclear what the effects of a military career are on the life trajectory of personnel who retire from service. We aimed to compare life expectancy among retired military personnel(RMP) to their sex- and birth cohortspecific reference ***: For this historical-cohort study we collected data on sex, year of birth, year of death, time in service, and rank at end of service for 4,862 Israeli RMPs. Data on reference populations were provided by the Israel Central Bureau of Statistics, by birth decade from 1900 to 1989. We calculated the difference between each individual RMP's age at death and the "expected" age at death, based on sex- and birth cohort-specific means in the reference populations. Results: Overall, 67.9% of RMPs lived longer than average relative to their sex specific birth cohort. This difference in life expectancy was more pronounced among women than among men. There was a significant trend of increasing difference between RMP males and reference males over time(P<0.002), whereas no significant trend was identified among females. Length of service and rank were not associated with relative longevity for ***: The mechanism of the protective effect of military service on life expectancy remains unknown, but our findings indicate that it affects men and women differently, with women being more likely to benefit from the protective effect of military service. The healthy worker effect is known to vary from one occupation to another. To the best of our knowledge, this is the first attempt to quantify the magnitude of the healthy worker effect among career military servicemen and women.

关键词： Occupation Life expectancy Longevity Military personnel

处理发展中国家疑似HIV感染和艾滋病患者的特别考虑

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国外医学（流行病学．传染病学分册） 1991年第3期18卷 126-127页

作者： kreiss JK 杨建国

本文讨论了HIV感染的地理分布与HIV传播的流行模式,评价了不同地区HIV感染的危险因素。作者根据不同国籍患者的不同临床表现,分别就非洲型、拉丁美洲型和海地型的临床特点进行了回顾性综述报道。

关键词： HIV 感染艾滋病处理

血友病病人的HTLV-Ⅲ抗体、淋巴结病和AIDS的关系:前瞻性研究结果

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中国冶金工业医学杂志 1986年第2期 22-27页

作者： kreiss JK 于吉荣鞍钢铁东医院

随访63例血友病病人与获得性免疫缺陷综合征相关的临床和免疫学变化。1984年初,在59％(41例中的24例)的接受因子Ⅷ或Ⅸ浓缩剂剂治疗的血清中,检出人类T细胞白血病病毒Ⅲ型(HTLV—Ⅲ)抗体,而接受冷沉淀/冰冻鲜血浆治疗者无1例阳性(0/6)。... 详细信息

随访63例血友病病人与获得性免疫缺陷综合征相关的临床和免疫学变化。1984年初,在59％(41例中的24例)的接受因子Ⅷ或Ⅸ浓缩剂剂治疗的血清中,检出人类T细胞白血病病毒Ⅲ型(HTLV—Ⅲ)抗体,而接受冷沉淀/冰冻鲜血浆治疗者无1例阳性(0/6)。HTLV—Ⅲ血清阳性的血友病人在过去的1年中所接受的浓缩剂量,比血清阴性的血友病人多2倍。血清阳性组的

关键词：血友病凝血障碍淋巴结病 AIDS 抗体 HTLV 病人前瞻性研究

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依赖时间问题的近似解法

依赖时间问题的近似解法

马萨诸塞州2008-2013年某复合泡沫塑料制造厂的工作相关哮喘

作者： H.·克拉斯(H. kreiss) J.·奥立格(J. Oliger)

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上海预防医学 2016年第7期28卷 518-519,F0004页

作者： Megan Casey Marcia L.Stanton Kristin J.Cummings Elise Pechter Kathleen Fitzsimmons Ryan F.LeBouf Christine R.Schuler Kathleen kreiss 周晓丹(翻译) 周惠嘉(审校) Epidemic Intelligence Service CDC Division of Respiratory Disease Studies National Institute for Occupational Safety and Health CDC Occupational Health Surveillance Program Massachusetts Department of Public Health Division of Safety Research National Institute for Occupational Safety and Health CDC 不详

工作相关哮喘是指因在工作场所中暴露于特定物质而引发或加重的哮喘。10%～16%的成人型哮喘病例可归因于职业因素,13%～58%的哮喘病例因工作加重。2008—2012年,马萨诸塞州公共卫生部共接到9份工作相关哮喘病例的报告,均来自一家生产海... 详细信息

工作相关哮喘是指因在工作场所中暴露于特定物质而引发或加重的哮喘。10%～16%的成人型哮喘病例可归因于职业因素,13%～58%的哮喘病例因工作加重。2008—2012年,马萨诸塞州公共卫生部共接到9份工作相关哮喘病例的报告,均来自一家生产海上油气工业漂浮装置所用的复合泡沫塑料工厂。

关键词：马萨诸塞州成人型职业因素油气工业医疗记录支气管炎症工作年限应答者海洋油气暴露情况