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Friction 2024年第3期12卷 375-395页

作者： Xiao YANG Heli LIU Lemeng ZHANG Yiran HU Denis J.POLITIS Mohammad M.GHARBI Liliang WANG Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK Department of Mechanical and Manufacturing Engineering University of CyprusNicosia 1678Cyprus Quaker Houghton deutschland gmbh Dortmund 44319Germany

The accurate representation of tribological boundary conditions at the tool–workpiece interface is crucial for analysis and optimization of formability,material flow,and surface quality of components during metal forming *** has been found that these tribological conditions vary spatially and historically with process parameters and contact *** time-dependent tribological behaviours are also known as transient tribological phenomena,which are widely observed during forming processes and many other manufacturing application ***,constant friction values are usually assigned to represent complex and dynamic interfacial conditions,which would introduce deviations in the relevant *** this paper,transient tribological phenomena and the contemporary understanding of the interaction between friction and wear are reviewed,and it has been found that these phenomena are induced by the transitions of friction mechanisms and highly dependent on complex loading conditions at the *** modelling techniques for transient behaviours for metal forming applications are also *** accurately describe the evolutionary friction values and corresponding wear during forming,the advanced interactive friction modelling has been established for different application scenarios,including lubricated condition,dry sliding condition(metal-on-metal contact),and coated system.

关键词： transient tribological phenomena interactive friction mechanism modelling techniques metal forming

Mechanism of cross-level settlements and void accumulation of wide and conventional sleepers in railway ballast

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Railway Engineering Science 2024年第3期32卷 361-383页

作者： Olga Nabochenko Mykola Sysyn Norman Krumnow Szabolcs Fischer Institute of Railway Systems and Public Transport Technical University of DresdenDresdenGermany Rhomberg Sersa deutschland gmbh BerlinGermany Central Campus Győr Széchenyi István UniversityGyorHungary

The cross-level and twist irregularities are the most dangerous irregularity types that could cause wheel unloading with the risk of derailments and additional maintenance ***,the mechanism of the irregularities initiation and development is *** motivation of the present study was the previous experimental studies on the application of wide sleepers in the ballasted *** long-term track geometry measurements with wide sleepers show an enormous reduction of the vertical longitudinal irregularities compared to the conventional ***,wide sleepers had higher twist and cross-section level *** present paper aims to explain the phenomenon by discrete element method(DEM)modeling the development process of sleeper inhomogeneous support at cross-level depending on the sleeper *** DEM simulations show that the maximal settlement intensity is up to 3.5 times lower for a wide sleeper in comparison with the conventional ***,the cross-level differential settlements are almost the same for both *** particle loading distribution after all loading cycles is concentrated on the smaller area,up to the half sleeper length,with fully unloaded zones under sleeper *** flow limitation under the central part of the sleeper could improve the resilience of wide sleepers to the development of cross-level *** mechanism of initiation of the cross-level irregularity is proposed,which assumes the loss of sleeper support under sleeper *** further growth of inhomogeneous settlements along the sleeper is assumed as a result of the interaction of two processes:ballast flow due to dynamic impact during void closing and on the other side high pressure due to the concentration of the pressure under the middle part of the *** DEM simulation results support the assumption of the mechanism and agree with the experimental studies.

关键词： Wide sleeper Ballasted track Sleeper support inhomogeneity Sleeper foot form Discrete element modeling Void accumulation

In memory of Friedrich Ackermann:a personal view

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Geo-Spatial Information Science 2023年第2期26卷 153-155页

作者： Ralf W.Schroth Blom deutschland gmbh SchorndorfGermany

The paper contains the author’s personal account of the professional achievements of Professor Friedrich(Fritz)Ackermann based on the author’s memories and private documents which demonstrate Ackermann’s significant influence throughout various professional phases over a period of four *** structure of the paper is based on the path of the author’s studies,the period as a member of the Institute of Photogrammetry at Stuttgart University,and finally,a professional career in photogrammetry,geoinformation and *** emphasis is on the character and skills of Friedrich ***,team spirit and social skills are demonstrated with impressive examples.

关键词： finally professional gramme

Problem Solving Solutions in Thermal Spray:HSE and Overspray

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有色金属（冶炼部分） 2008年第S1期 139-145页

作者： Hans Keller Joachim Beczkowiak Stefan Zimmermann Benno Gries Jürgen Fischer H.C.Starck gmbh LaufenburgDeutschland H.C.Starck gmbh GoslarDeutschland

目前金属基材料的原材料成本对热喷涂涂层的经济性造成压力。特别是材料挥发和近期铼、钨、钴和镍基材料的价格增长,对各应用领域的许多涂层的经济性造成严重威胁。由于沉积效率的限制,喷涂中未沉积物问题变得越来越重要,不仅只是减少浪... 详细信息

目前金属基材料的原材料成本对热喷涂涂层的经济性造成压力。特别是材料挥发和近期铼、钨、钴和镍基材料的价格增长,对各应用领域的许多涂层的经济性造成严重威胁。由于沉积效率的限制,喷涂中未沉积物问题变得越来越重要,不仅只是减少浪费,还可以从材料自身价值角度去看。回收是解决这个问题的一个措施,特别是当废料中含有高价值金属时。欧洲执行的REACH(化学制品的注册、评估、授权)将会逐步强制淘汰标有有毒的材料和物质的使用。在热喷涂中使用这些有毒物质或使用热喷涂产品可能暂时是安全的,然而,从法律限制和从其他工业领域得到的指示表明,像WC-Co粉末这样的化学制品对人体有害。要想在将来的涂层工厂中保持竞争性,必须符合不断提高的更严格的环保和安全规程。

关键词：热喷涂粉末 WC-Co 健康和环保毒物学回收喷涂中未沉积物

Connected morphable components-based multiscale topology optimization

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Frontiers of Mechanical Engineering 2019年第2期14卷 129-140页

作者： Jiadong DENG Claus B.W.PEDERSEN Wei CHEN Department of Mechanical Engineering Northwestern UniversityEvanstonIL 60208USA Dassault Systemes deutschland gmbh 200095 HamburgGermany

The advances of manufacturing techniques,such as additive manufacturing,have provided unprece-dented opportunities for producing multiscale structures with intricate latticed/cellular material microstructures to meet the increasing demands for parts with customized ***,there are still difficulties for the state-of-the-art multiscale topology optimization(TO)methods to achieve manufacturable multiscale designs with cellular materials,partially due to the disconnectivity issue when tiling material *** paper attempts to address the disconnectivity issue by extending component-based TO methodology to multiscale structural *** effective linkage scheme to guarantee smooth transitions between neighboring material microstructures(unit cells)is devised and *** with the advantages of components-based TO,the number of design variables is greatly reduced in multiscale TO *** is employed to calculate the effective material properties of the porous materials and to correlate the macro/structural scale with the micro/material *** of the objective function with respect to the geometrical parameters of each component in each material microstructure have been derived using the adjoint *** examples demonstrate that multiscale structures with well-connected material microstructures or graded/layered material microstructures are realized.

关键词： multiscale topology optimization morphable component material microstructure homogenization

Wireless data transmission using visual codes

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Photonics Research 2014年第5期2卷 150-160页

作者： Thilo Fath Falk Schubert Harald Haas Institute for Digital Communications University of EdinburghEH93JL EdinburghUK Innovation Works Germany EADS Deutschland GmbH81663 MunichGermany

In this paper,a new approach for wireless data transmission within an aircraft cabin is *** proposed application enables the transmission of data to a passenger’s user *** wireless in-flight applications are subject to strict frequency and electromagnetic compatibility(EMC)regulations,the data is transferred by optical wireless transmission,specifically by two-dimensional visual *** this end,black-and-white or colored visual code sequences are displayed on the in-flight entertainment *** visual codes are captured by the built-in camera of the passenger’s mobile device and are decoded to reconstruct the transmitted *** order to compensate for frame losses caused by effects like occlusion and motion blur,a temporal forward error correction coding scheme is *** experiments within an Airbus A330 cabin mock-up demonstrate the functionality of the implemented system under realistic conditions such as ambient illumination and geometric *** user devices are used for evaluation;specifically,a low-cost and a high-end smartphone are employed as *** evaluations show that the proposed transmission system achieves data rates of up to 120 kbit/s per individual passenger seat with these user *** the user device has no physical connection to the sensitive on-board system,the proposed transmission system provides an intrinsic safety feature.

关键词： visual illumination correction

Determination of serum biomarkers in osteoarthritis patients：a previous interventional imaging study revisited

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The Journal of Biomedical Research 2017年第1期31卷 25-30页

作者： Timothy McAlindon Eckart Bartnik Janina S.Ried Lenore Teichert Matthias Herrmann Klaus Flechsenhar Tufts Medical Center Division of RheumatologyBostonMA 02111USA Sanofi-Aventis deutschland gmbh Frankfurt am Main D-65926Germany

To evaluate in an interventional trial on knee osteoarthritis（OA） the level and change of two serum biomarkers and their correlation with imaging *** previously reported interventional OA study（***：NCT00536302） identified a positive effect of collagen hydrolysate（CH） on cartilage morphology in patients with knee OA using delayed gadolinium enhanced magnetic resonance imaging（dGEMRIC）.It was the objective in this research project to evaluate in an interventional clinical trial on knee OA the level and change of two serum biomarkers and their correlation with imaging *** blood samples of study participants,we determined the concentration of procollagen type II N-terminal propeptide（PIIANP） and aggrecan chondroitin sulfate 846 epitope（CS846） at baseline（BL） and at the follow-up（FU） visits at 24 and 48 *** measured the level and change of biomarker concentrations in both study groups,and the correlation of those changes with changes in *** the biomarker PIIANP,we observed a significantly greater increase in the CH group（29.9%vs.1.2%at week 24,P =0.001）.For CS846,the mean concentration was lower among the CH treated participants at 24 weeks（78%vs.96%,P= 0.045）.Consistent correlations of changes in biomarkers PIIANP and CS846 with changes of the dGEMRIC score could not be *** this study,different changes per treatment group,CH and placebo were seen for dGEMRIC and PIIANP BL to 24 weeks FU,but only weak correlations between changes in dGEMRIC and biochemical markers.

关键词： knee osteoarthritis interventional trial magnetic resonance imaging serum chemical biomarkers

A Virtual Prototyping Approach for Development of PMSM on Real‑Time Platforms: A Case Study on Temperature Sensitivity

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Automotive Innovation 2022年第3期5卷 285-298页

作者： René Scheer Yannick Bergheim Simon Aleff Daniel Heintges Niclas Rahner Rafael Gries Jakob Andert Teaching and Research Area Mechatronics in Mobile Propulsion RWTH Aachen UniversityForckenbeckstr.4Aachen 52074Germany DENSO Automotive deutschland gmbh Friedrich‑List‑Allee 42Wegberg 41844Germany

This paper presents a comprehensive evaluation of system interactions in a battery electric vehicle caused by temperature sensitivity of permanent magnet synchronous machines(PMSM).An analytical model of a PMSM considering iron losses and thermal impact is implemented on a field programmable gate array suitable for hardware-in-the-loop *** the presented virtual prototyping approach,different machine characteristics defined by the design are used to parameterize the analytical *** investigated temperature effect is understood as an interacting influence between machine character-istics and control,which are investigated in terms of torque generation,voltage utilization and efficiency under closed-loop condition in a vehicle *** particular,using a surface permanent magnet rotor and an interior permanent magnet rotor,the performance of both machine designs is analyzed by varying temperature-adjusted feedforward control strategies on the basis of a driving cycle from a *** comparison shows that the machine design with surface-mounted mag-nets is associated with higher temperature *** this case,the temperature consideration in the feedforward control provides a14%loss reduction in closed-loop vehicle test *** can be summarized that the electromagnetic torque is less sensitive to a temperature variation with increasing *** presented development approach demonstrates the impact of interactions in electric powertrains without the need of real prototypes.

关键词： FPGA PMSM Iron loss FEM Spatial harmonics RT-MIL Virtual prototyping Frontloading Closed-

Antidiabetic profiling of veramycins,polyketides accessible by biosynthesis,chemical synthesis and precursor-directed modification

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Organic Chemistry Frontiers 2022年第6期9卷 1604-1615页

作者： Denis Dardić Nils Böhringer Alberto Plaza Florian Zubeil Juliane Pohl Svenja Sommer Leo Padva Jonathan Becker Maria A.Patras Mona-Katharina Bill Michael Kurz Luigi Toti Sven W.Görgens Sören M.M.Schuler AndréBillion Oliver Schwengers Paulus Wohlfart Alexander Goesmann Norbert Tennagels Andreas Vilcinskas Peter E.Hammann Till F.Schäberle Armin Bauer Fraunhofer Institute for Molecular Biology and Applied Ecology(IME) Branch for Bioresources35392 GießenGermany Justus-Liebig-University Gießen 35392 GießenGermany Sanofi-Aventis deutschland gmbh R&D Integrated Drug Discovery65926 Frankfurt am MainGermany Sanofi-Aventis deutschland gmbh R&D German Hub65926 Frankfurt am MainGermany German Center of Infection Research(DZIF) Partner Site Gießen-Marburg-Langen35392 GießenGermany

Seven new polyketides,termed veramycins,were isolated from a Streptomyces *** the Sanofi microbial strain collection along with their known congeners NFAT-133 and *** A,anα-pyrone congener of TM-123 and NFAT-133 showed an increased baseline deoxy-glucose uptake in the absence of insulin in a modified L6 rat skeletal muscle cell line(L6 GLUT4 AS160-like cells).In addition,both compounds slightly increased the sensitivity to insulin in this cell *** syntheses of NFAT-133,TM-123 and veramycin A were accomplished starting from a central building block,which bears the three contiguous stereogenic centers of this polyketide *** approach enables an efficient,selective and flexible access to all possible isomers of the stereotriad for further exploration of this series as a potential anti-diabetic lead structure as exemplified by the synthesis of an NFAT-133 ***,the corresponding biosynthetic gene cluster(BGC)was identified by genome sequencing and gene *** on feeding experiments,a biosynthetic pathway was proposed,which enabled access to new veramycin A analogs by precursor-directed biosynthesis.

关键词： synthesis directed isomers

The Origin of the Giant Hall Effect in Metal-Insulator Composites

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Open Journal of Composite Materials 2016年第3期6卷 78-90页

作者： Joachim Sonntag MEAS deutschland gmbh a TE Connectivity LTD Company Dortmund Germany

Near the metal-insulator transition, the Hall coefficient R of metal-insulator composites (M-I composite) can be up to 104 times larger than that in the pure metal called Giant Hall effect. Applying the physical model for alloys with phase separation developed in [1] [2], we conclude that the Giant Hall effect is caused by an electron transfer away from the metallic phase to the insulating phase occupying surface states. These surface states are the reason for the granular structure typical for M-I composites. This electron transfer can be described by [1] [2], provided that long-range diffusion does not happen during film production (n is the electron density in the phase A. uA and uB are the volume fractions of the phase A (metallic phase) and phase B (insulator phase). β is a measure for the average potential difference between the phases A and B). A formula for calculation of R of composites is derived and applied to experimental data of granular Cu1-y(SiO2)y and Ni1-y(SiO2)y films.

关键词： Metal-Insulator Composites Granular Metals Hall Coefficient Conductivity Electron Density