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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

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

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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

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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

Tensorial tomographic Fourier ptychography with applications to muscle tissue imaging

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Advanced Photonics 2024年第2期6卷 50-60页

作者： Shiqi Xu Xi Yang Paul Ritter Xiang Dai Kyung Chul Lee Lucas kreiss Kevin C.Zhou Kanghyun Kim Amey Chaware Jadee Neff Carolyn Glass Seung Ah Lee Oliver Friedrich Roarke Horstmeyer Duke University DurhamNorth CarolinaUnited States Friedrich-Alexander University ErlangenGermany UC San Diego La JollaCaliforniaUnited States Yonsei University SeoulRepublic of Korea UC Berkeley BerkeleyCaliforniaUnited States Duke University Medical Center DurhamNorth CarolinaUnited States

We report tensorial tomographic Fourier ptychography(T^(2)oFu),a nonscanning label-free tomographic microscopy method for simultaneous imaging of quantitative phase and anisotropic specimen information in *** upon Fourier ptychography,a quantitative phase imaging technique,T^(2)oFu additionally highlights the vectorial nature of *** imaging setup consists of a standard microscope equipped with an LED matrix,a polarization generator,and a polarization-sensitive *** tensors of anisotropic samples are computationally recovered from polarized intensity measurements across three *** demonstrate T^(2)oFu’s efficiency through volumetric reconstructions of refractive index,birefringence,and orientation for various validation samples,as well as tissue samples from muscle fibers and diseased heart *** reconstructions of healthy muscle fibers reveal their 3D fine-filament structures with consistent ***,we demonstrate reconstructions of a heart tissue sample that carries important polarization information for detecting cardiac amyloidosis.

关键词： computational imaging three-dimensional imaging phase retrieval microscopy polarization-sensitive imaging labelfree imaging

Digital staining in optical microscopy using deep learning-a review

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PhotoniX 2023年第1期4卷 64-95页

作者： Lucas kreiss Shaowei Jiang Xiang Li Shiqi Xu Kevin C.Zhou Kyung Chul Lee Alexander Mühlberg Kanghyun Kim Amey Chaware Michael Ando Laura Barisoni Seung Ah Lee Guoan Zheng Kyle J.Lafata Oliver Friedrich Roarke Horstmeyer Department of Biomedical Engineering Duke UniversityDurhamNC 27708USA Institute of Medical Biotechnology Friedrich-Alexander University(FAU)ErlangenGermany Department of Biomedical Engineering University of ConnecticutMansfieldConnecticutUSA Department of Radiation Physics Duke UniversityDurhamNC 27708USA Department of Electrical Engineering&Computer Sciences University of CaliforniaBerkeleyCAUSA School of Electrical&Electronic Engineering Yonsei UniversitySeoul 03722Republic of Korea Google Inc.Mountain ViewCA 94043USA Department of Pathology Duke UniversityDurhamNC 27708USA

Until recently,conventional biochemical staining had the undisputed status as well-established benchmark for most biomedical problems related to clinical diagnostics,fundamental research and *** this role as gold-standard,staining protocols face several challenges,such as a need for extensive,manual processing of samples,substantial time delays,altered tissue homeostasis,limited choice of contrast agents,2D imaging instead of 3D tomography and many ***-free optical technologies,on the other hand,do not rely on exogenous and artificial markers,by exploiting intrinsic optical contrast mechanisms,where the specificity is typically less obvious to the human *** the past few years,digital staining has emerged as a promising concept to use modern deep learning for the translation from optical contrast to established biochemical contrast of actual *** this review article,we provide an in-depth analysis of the current state-of-the-art in this field,suggest methods of good practice,identify pitfalls and challenges and postulate promising advances towards potential future implementations and applications.

关键词： Deep learning Digital staining Optical microscopy Virtual staining In-silica Pseudo-H&E Virtual fluorescence Generative models Image translation

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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