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Three-Dimensional Mode Coupling around a Conical Seamount and the Use of Random Discretization

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Chinese Physics Letters 2010年第11期27卷 137-140页

Three-dimensional mode coupling around a conical seamount in an ocean waveguide is studied. It is shown that strong mode coupling occurs at the edge of a conical seamount for the incident normal modes with significant amplitudes below the top of the seamount. Therefore, mode coupling is critical for the investigation of the acoustic field around a seamount. In addition, we suggest the use of random discretization for representing smoothly varying bathymetry. For the use of uniform discretization, when the horizontal step size is greater than half of the wavelength, artificial diffraction lobes appear due to coherent backscatter. However, by using the random discretization scheme instead, such artificial diffraction lobes are diffused, resulting in a faster convergence rate.

关键词： Environmental and Earth science

Three-dimensional mode coupling around a seamount

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Science China(Physics,Mechanics & Astronomy) 2011年第9期54卷 1561-1569页

作者： LUO WenYu ZHANG RenHe schmidt henrik State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190 China Department of Mechanical Engineering Massachusetts Institute of Technology Massachusetts 02139 USA

A recently developed three-dimensional normal-mode model is adopted to investigate mode coupling around a seamount in a deep water environment. As indicated by the theoretical analysis and verified by the numerical results, strong mode coupling occurs at the edge of a seamount under certain conditions. Therefore, mode coupling is critical for the investigation of the acoustic field in the presence of a seamount. In addition, the issue regarding the number of sectors assuring convergence is also presented. This issue is important in a two-way coupled-mode approach, especially for solving three-dimensional problems, because the computational effort increases dramatically with the number of sectors in representing a varying bathymetry. The theoretical analysis as well as the numerical example in this paper shows that artificial diffraction lobes form in the event that uniform discretization is used with a horizontal step size greater than half of the acoustic wavelength. However, by using random discretization instead, such artificial diffraction lobes are diffused, resulting in a faster convergence rate.

关键词： normal mode three-dimensional mode coupling seamount

水平变化波导中声传播问题的高效稳定耦合简正波解

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声学学报 2011年第6期36卷 568-578页

作者：骆文于张仁和 schmidt henrik 中国科学院声学研究所声场声信息国家重点实验室北京100190 麻省理工学院机械工程系美国剑桥02139

提出了一种高效、精确而且数值稳定的耦合简正波方法,用于求解水平变化波导中的声传播问题。与现有的数值模型相比,本方法采用合理的归一化距离解,极大地提高了数值稳定性;通过结合一个前向传播过程和一个后向传播过程,该方法极大地提... 详细信息

提出了一种高效、精确而且数值稳定的耦合简正波方法,用于求解水平变化波导中的声传播问题。与现有的数值模型相比,本方法采用合理的归一化距离解,极大地提高了数值稳定性;通过结合一个前向传播过程和一个后向传播过程,该方法极大地提高了计算精度,可用于精确求解水平变化波导中的声传播问题,尤其适用于大角度斜坡以及海底与海水声阻抗差别较大的问题;此外,通过采用单次散射近似,该方法极大地提高了计算效率,而且对计算条件要求较低。从数值结果可以看出,本方法是一种高效、精确而且数值稳定的求解水平变化波导声传播问题的耦合简正波方法。

关键词：数值稳定性水平变化声传播简正波波导耦合精确求解传播过程

Severe steroid refractory gastritis induced by Nivolumab: A case report

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World Journal of Gastroenterology 2020年第16期26卷 1971-1978页

作者： Helene Hjorth Vindum JØrgen S Agnholt Anders Winther Moelby Nielsen Mette Bak Nielsen henrik schmidt Department of Oncology Aarhus University HospitalAarhus 8200Denmark Department of Gastroenterology Aarhus University HospitalAarhus 8200Denmark Department of Pathology Aarhus University HospitalAarhus 8200Denmark

BACKGROUND Immune checkpoint inhibitors are widely used for treatment of many advanced *** gastrointestinal(GI)side effects,such as diarrhea and colitis,are common,but upper GI side effects are rarely ***,the correct treatment of upper GI adverse events has been less frequently *** SUMMARY We describe a case of a 16-year-old woman with stage IIIb malignant melanoma treated with adjuvant monotherapy using *** patient developed severe gastritis after six series of Nivolumab with weight loss,nausea,and *** was no effect of intravenous steroids,but the patient′s condition resolved after administration of *** This case report supports the same treatment for gastritis as for colitis,which is in line with current guidelines.

关键词： Gastritis Immune checkpoint inhibitors Nivolumab Case report Immune-related adverse events Infliximab

A two-way marching coupled-mode method for range-dependent propagation

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Chinese Journal of Acoustics 2012年第4期31卷 371-391页

作者： LUO Wenyu ZHANG Renhe schmidt henrik Institute of Acoustics Chinese Academy of Sciences Beijing 100190 Department of Mechanical Engineering MIT Cambridge MA 02139 USA

An efficient, accurate, and numerically stable coupled-mode solution is presented for acoustic propagation in a range-dependent waveguide. This method is numerically stable due to the appropriately normalized range solutions introduced in the formulation. In addition, by combining a forward marching and a backward marching, this method provides accurate solu- tions for range-dependent propagation problems, especially those characterized by large bottom slope angle and/or high impedance contrast between water and the bottom. Furthermore, this two-way solution also provides high efficiency, which is achieved by applying the single-scatter approximation. Numerical examples are also provided to demonstrate the efficiency, accuracy, and stability of this method.

关键词：声波传播耦合模式数值稳定标准化稳定性

Wedge Splitting Test and Inverse Analysis on Fracture Behaviour of Fiber Reinforced and Regular High Performance Concretes

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Journal of Civil Engineering and Architecture 2014年第5期8卷 595-603页

作者： Kamil Hodicky Thomas Hulin Jacob W. schmidt henrik Stang Department of Civil Engineering Technical University of Denmark Kongens Lyngby DK-2800 Denmark

The fracture behaviour of three fiber reinforced and regular HPC （high performance concretes） is presented in this paper. Two mixes are based on optimization of HPC whereas the third mix was a commercial mix developed by CONTEC ApS （Denmark）. The wedge splitting test setup with 48 cubical specimens was used experimentally and the cracked non-linear hinge model based on the fictitious crack model was applied for the interpretation of the results. The stress-crack opening relationships were extracted by using inverse analysis algorithm for various multi-linear softening curves. This showed that the refinement of the softening curves reflects in improved accuracy of the WST （wedge splitting test） simulation in comparison with bi-linear softening curves with acceptable increase of computational time. Furthermore, the fracture mechanics parameters such as COD （crack opening displacement）, fracture energy and characteristic length were experimentally determined. Experiments were performed at 1, 3, 7 and 28 days. Fracture energy, Gf, was found to increase with age, while the characteristic length, Lch, was found to decrease.

关键词： High performance concrete wedge splitting test inverse analysis fictitious crack model.

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海山附近三维声传播与散射

海山附近三维声传播与散射

喷雾干燥吸收(SDA)满足SO_2低量排放指标的烟气脱硫工艺

泛在信息社会中的声学——中国声学学会2010年全国会员代表大会暨学术会议

作者：骆文于 schmidt henrik 张仁和中国科学院声学研究所声场声信息国家重点实验室 Massachusetts Institute of Technology

1引言过去几十年来,大量的声传播模型被开发出来,其中大多数用来求解二维问题(距离和深度),当环境随方位角变化可以忽略时,可提供准确结果。但是,对一些问题,如海山、海岛、强漩涡等附近声传播问题,三维效应是不能被忽略的,因而

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中国钢铁业 2009年第3期 52-54页

作者： henrik Monsted schmidt

喷雾干燥吸收(SDA)工艺是应用范围排在世界第二位的烟气脱硫技术,目前已投入运行的燃煤锅炉SDA烟气净化装置总装机容量大约为22GMe(1*IEACCC-2006.8)。

关键词：烟气脱硫工艺喷雾干燥排放指标吸收 SO2 烟气脱硫技术烟气净化装置装机容量

喷雾干燥吸收（SDA）——高灵活性的烟气净化工艺

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冶金环境保护 2008年第5期 23-26页

作者： henrik Mφnsted schmidt Carsten Hillmann 丹麦尼鲁公司 DK Recycling und Roheisen GmbH 公司

DK Recycling und Roheisen GmbH公司在德国杜伊斯堡的烧结厂从含铁废渣中生产铁烧结矿。铁烧结矿在高炉中进一步熔化成铸造生铁。在1998年以前，该烧结厂的烟气净化设备只有一台电除尘器。1998年将一套喷雾干燥吸收（SDA）烟气净化系... 详细信息

DK Recycling und Roheisen GmbH公司在德国杜伊斯堡的烧结厂从含铁废渣中生产铁烧结矿。铁烧结矿在高炉中进一步熔化成铸造生铁。在1998年以前，该烧结厂的烟气净化设备只有一台电除尘器。1998年将一套喷雾干燥吸收（SDA）烟气净化系统安装在原电除尘器下游，进一步去除烟气中的SO2、SO3、HCl、HF、二嗯英、呋喃、汞和其它重金属，以满足当地新的环保要求。由于此烧结厂使用回收铁渣作为原料，工艺条件波动剧烈，尼鲁公司专门设计了具有高灵活性的SDA系统以适应工艺条件变化的挑战。在过去10年里，这一烟气净化系统的运行经验表明，尼鲁公司的SDA工艺是一种耐用、可靠、灵活性高的工艺。尼鲁公司的SDA装置表现出了出色的性能——操作弹性大、烟气净化效率高、运行维护要求低。此外，在DK Recycling und Roheisen GmbH公司过去10年的运行中，SDA装置的可利用率高于99％。

关键词：烟气净化工艺高灵活性喷雾干燥吸收 GmbH公司烟气净化设备运行经验烟气净化系统