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Reduced multibody system transfer matrix method using decoupled hinge equations

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International Journal of Mechanical System Dynamics 2021年第2期1卷 182-193页

作者： Xue Rui dieter bestle Engineering Mechanics and Vehicle Dynamics Brandenburg University of TechnologyCottbusGermany Institute of Launch Dynamics Nanjing University of Science and TechnologyNanjingChina

In the multibody system transfer matrix method(MSTMM),the transfer matrix of body elements may be directly obtained from kinematic and kinetic ***,regarding the transfer matrices of hinge elements,typically information of their outboard body is involved complicating modeling and even resulting in combinatorial problems *** types of outboard body's output *** problem may be resolved by formulating decoupled hinge equations and introducing the Riccati transformation in the new version of MSTMM called the reduced multibody system transfer matrix method in this *** procedures for chain,tree,closed-loop,and arbitrary general systems are defined,respectively,to generate the overall system equations satisfying the boundary conditions of the system during the entire computational *** a result,accumulation errors are avoided and computational stability is guaranteed even for huge systems with long chains as demonstrated by examples and comparison with commercial software automatic dynamic analysis of the mechanical system.

关键词： general system topology multibody system dynamics reduced transformation transfer matrix method

A new exceptionally preserved corystosperm wood from the Jurassic of East Asia

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Science China Earth Sciences 2025年第3期68卷 803-810页

作者： Zikun JIANG Ning TIAN Yongdong WANG Fangyu LI Junling PEI dieter UHL Ya LI Hao WU Zhenguo NING Ruiying HAO Chinese Academy of Geological Sciences College of Palaeontology Shenyang Normal University Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences College of Resources and Environmental Engineering Guizhou University East China University of Technology Senckenberg Research Institute and Natural History Museum Frankfurt Zhejiang Museum of Natural History Department of Natural Resources of Shandong Province

Corystosperms, an extinct group of “seed ferns” that lived from the late Permian to the Cretaceous or Eocene, are significant for seed plant phylogeny for their unique roles in partially resolving the long-standing question of angiosperm origins.A new fossil wood taxon, Fengweioxylon sinense gen. et sp. nov. is reported here based on exceptionally preserved wood material from the Jurassic in western Liaoning, China, whose peculiar wood structure enables it to be recognized as the first unequivocal fossil wood record of a corystosperm plant in Laurasia. The anatomical structures of this corystosperm wood show gymnospermous characters. The discovery of the new specimen will provide more anatomical evidence for understanding the systematic and affinity of this seed plants.

关键词： Corystosperms Fossil wood Laurasia Jurassic

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东亚侏罗纪一种保存完好的新型盔籽类植物

中国科学:地球科学 2025年第3期55卷 826-834页

作者：蒋子堃田宁王永栋李芳雨裴军令 dieter UHL 李亚吴灏宁振国郝瑞莹中国地质科学院沈阳师范大学古生物学院中国科学院南京地质古生物研究所贵州大学资源与环境工程学院华东理工大学 Senckenberg Research Institute and Natural History Museum Frankfurt 浙江自然博物院山东省自然资源厅

盔籽类植物是一种已经灭绝的种子蕨植物类群,生活在晚二叠世到白垩纪或始新世,在种子植物系统发育中具有重要意义,因此在部分解决长期困扰人们的有关被子植物起源问题方面发挥着独特作用.本文报道了中国辽西侏罗纪发现的一个新的木材化... 详细信息

盔籽类植物是一种已经灭绝的种子蕨植物类群,生活在晚二叠世到白垩纪或始新世,在种子植物系统发育中具有重要意义,因此在部分解决长期困扰人们的有关被子植物起源问题方面发挥着独特作用.本文报道了中国辽西侏罗纪发现的一个新的木材化石分类群——中华凤尾木(新属新种)(Fengweioxylon sinense gen. et sp. nov. Jiang, Tian et Wang).该化石保存完好,且解剖结构展现出裸子植物的独特特征,代表劳亚大陆第一个确凿的盔籽类植物木化石记录.这一新标本的发现为探究该种子植物的系统发育和亲缘关系提供了重要的解剖学证据.

关键词：盔籽植物木化石劳亚大陆侏罗纪

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Hybrid system-a promising way solving future energy problems

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航空动力学报 2007年第4期22卷 565-576页

作者： dieter Bohn Institute of Steam and Gas Turbines RWTH Aachen University

With the increasing demand for electricity,an efficiency improvement and thereby reduced CO2 emissions of the power plants are expected in order to reach the goals set in the Kyoto *** comparison to conventional systems,the hybrid-systems with the use of synergetic effects offer the possibility to provide a substantial contribution to spare our natural resources and protect our *** Cycle Power Plants belongs innately hybrid system in the centralized energy *** can provide large amounts of power and have a quick start-up *** MGT/FC hybrid system is quite promising in the decentralized energy *** is widely used in stand-alone ***,the combination of fossil and renewable power plant technologies contains a large synergy potential to increase the efficiency of processes for power *** materials,innovative cooling technology,new combustion concepts and optimized production methods are needed to make the potential of these new technologies accessible for a quantum leap in the *** this it needs considerable research work and good coordinated research projects between the state,industry,research laboratories and universities.

关键词：航空推进系统混合燃料涡轮机能源

Designing a power plant with highest efficiency:results from SFB 561

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航空动力学报 2009年第4期24卷 717-728页

作者： dieter Bohn Institute of Steam and Gas Turbines RWTH Aachen University

The goal of Collaborative Research Centre(SFB) 561 "thermally highly loaded,porous and cooled multi-layer systems for combined cycle power plants" is to expand the current technological and scientific knowledge on power plants in order to achieve total efficiencies of 65% in a combined cycle power plant in the year ***,the aero-thermomechanical,structural-mechanical,materials' scientific and production fundamentals for the development of steam and gas turbine components that are able to withstand highest thermal loads are being worked out within this *** means for the gas turbine that combustion chamber outlet temperatures of 1520℃ at 1.7MPa are to be *** order to control these high temperatures,it is not only required to develop new materials' solutions,including thermal barrier coatings,but also to apply improved cooling techniques,as for example effusion *** novel cooling concept is to be realised through open-porous *** structures can consist of drilled open-porous multi-layer systems or open-porous metallic *** development of graded multi-layer systems is also extremely important,as the grading will enable the use of coolant in dependence of the *** live steam parameters in the high pressure turbine are expected to be increased up to approximately 700℃ with pressure of *** elevated steam parameters can be encountered with Ni-base alloys,but this is a costly alternative,associated with many manufacturing ***,the SFB proposes cooling the highly loaded turbines instead,as this would necessitate the application of far less Ni-base *** protect the thermally highly loaded casing,a sandwich material consisting of two thin face sheets with a core of a woven wire mesh is used to cover the walls of the steam turbine *** current state of the research shows that by utilising innovative cooling technologies a total efficiency of 65% can be reached without exceeding the m

关键词： gas turbine steam turbine cooling novel materials process calculation

The Vγ4/butyrophilin conspiracy: novel role of intraepithelial γδ T cells in chronic inflammatory bowel disease

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Signal Transduction and Targeted Therapy 2023年第12期8卷 5575-5577页

作者： dieter Kabelitz Institute of Immunology Christian-Albrechts University Kiel and University Hospital Schleswig-Holstein Campus KielKielGermany

In a recent article published in Science,Dart and colleagues reported that colonic T cells expressing the Vγ4 T-cell receptor(TCR)interact with epithelial butyrophilin-like(BTNL)proteins BTNL3 and BTNL8 in healthy individuals,and they observed a depletion of Vγ4 T cells in inflammatory bowel diseases with renormalization associated with disease remission.1 This paper identifies the BTNL/Vγ4 axis as a new disease modifier in IBD.

关键词： bowel inflammatory diseases

Welding mechanics for advanced component safety assessment

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Frontiers of Materials Science 2011年第2期5卷 224-235页

作者： dieter SIEGELE Fraunhofer Institute for Mechanics of Materials IWM WShlerstr. 11 79108 Freiburg Germany

Numerical methods are nowadays a useful tool for the calculation of distortion and residual stresses as a result from the welding process. Modern finite element codes not only allow for calculation of deformations and stresses due to the welding process but also take into account the change of microstructure due to different heating and cooling rates. As an extension to the pure welding simulation, the field of welding mechanics combines the mechanics and the material behaviour from the welding process with the assessment of service behaviour of welded components. In the paper, new results of experimental and numerical work in the field of welding mechanics are described. Through examples from automotive, nuclear and pipe-line applications it is demonstrated that an equilibrated treatment and a close interaction of ＂process＂, ＂properties＂ and ＂defects＂ are necessary to come up with an advanced fitness-forservice assessment of welded components.

关键词： welding simulation residual stress defect assessment fracture mechanics

Lab experiments on the innovative rapid thick strip casting process

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International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 391-398页

作者： Richard Nagy dieter Senk Department of Ferrous Metallurgy IEHK RWTH Aachen UniversityAachen 52056Germany

Rapid thick strip casting （RTSC） by Anton Hulek, Inventmetall, is an innovative concept for the production of hot strips with a final as-cast thickness of about 25 mm before rolling. The innovation of the mechanism consists in a vertical mould performing a caterpillar motion. This moving mould has an unconventional parallelogram-shaped cross-section. The conventional rectangular shape is formed in the shaping machine, which is placed straight below the mould. Further elements of the technology are state-of-the-art. For the investigation of this new casting system theoretical calculations were complemented with practical experiments. The investigation focused mainly on two key aspects： the characteristics of the mould and the shaping process. For the practical analysis a static mould with three pairs of elements in laboratory scale was developed and commissioned by the Dept. of Ferrous Metallurgy @ RWTH Aachen University. The shaping experiments were carried out in model scale with two different materials and in variable boundary conditions. The results of these experiments delivered important mechanical as well as thermal informations about the casting system.

关键词： continuous casting rapid solidification strip metal moulds near-net-shape casting

PET imaging in ischemic cerebrovascular disease:current status and future directions

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Neuroscience Bulletin 2014年第5期30卷 713-732页

作者： Wolf-dieter Heiss Max Planck Institute for Neurological Research

Cerebrovascular diseases are caused by interruption or significant impairment of the blood supply to the brain, which leads to a cascade of metabolic and molecular alterations resulting in functional disturbance and morphological damage. These pathophysiological changes can be assessed by positron emission tomography （PET）, which permits the regional measurement of physiological parameters and imaging of the distribution of molecular markers. PET has broadened our understanding of the flow and metabolic thresholds critical for the maintenance of brain function and morphology： in this application, PET has been essential in the transfer of the concept of the penumbra （tissue with perfusion below the functional threshold but above the threshold for the preservation of morphology） to clinical stroke and thereby has had great impact on developing treatment strategies. Radioligands for receptors can be used as early markers of irreversible neuronal damage and thereby can predict the size of the final infarcts; this is also important for decisions concerning invasive therapy in large （＂malignant＂） infarctions. With PET investigations, the reserve capacity of blood supply to the brain can be tested in obstructive arteriosclerosis of the supplying arteries, and this again is essential for planning interventions. The effect of a stroke on the surrounding and contralateral primarily unaffected tissue can be investigated, and these results help to understand the symptoms caused by disturbances in functional networks. Chronic cerebrovascular disease causes vascular cognitive disorders, including vascular dementia. PET permits the detection of the metabolic disturbances responsible for cognitive impairment and dementia, and can differentiate vascular dementia from degenerative diseases. It may also help to understand the importance of neuroinflammation after stroke and its interaction with amyloid deposition in the development of dementia. Although the clinical application of PET

关键词： stroke dementia PET brain metabolism brain ischemia