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Parameter Identification and Controller Design for the Velocity Loop in Motion Control Systems

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Intelligent Control and Automation 2011年第3期2卷 251-257页

作者： Reimund Neugebauer stefan hofmann Arvid Hellmich Holger Schlegel 不详

Today the controller commissioning of industrial used servo drives is usually realized in the frequency domain with the open-loop frequency response. In contrast to that the cascaded system of position loop, velocity loop and current loop, which is standard in industrial motion controllers, is described in literature by using parametric models. Several tuning rules in the time domain are applicable on the basis of these parametric descriptions. In order to benefit from the variety of tuning rules an identification method in the time domain is required. The paper presents a method for the identification of plant parameters in the time domain. The approach is based on the auto relay feedback experiment by ?str?m/ H?gglund and a modified technique of gradual pole compensation. The paper presents the theoretical description as well as the implementtation as an automatic application in the motion control system SIMOTION. The identification results as well as the achievable performance on a test rig with a PI velocity controller will be presented.

关键词： Identification Parametric Models Controller Design Motion Control

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Analysis of pacemaker channel function by gene deletion

作者： (美)斯蒂芬·G. 霍夫曼(stefan G. hofmann)

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Analysis of pacemaker channel function by gene deletion

Hybrid multi-chip assembly of optical communication engines by in situ 3D nanolithography

第十五届国际药理学大会

作者： Andreas Ludwig Juliane Stieber stefan Herrmann Franz hofmann Institute of Pharmacology and Toxicology 91054 Erlangen Germany Institute of Pharmacology and Toxicology 80802 Muenchen Germany Institute of Pharmacology and Toxicology 91054 Erlangen Germany Institute of Pharmacology and Toxicology 80802 Muenchen Germany

＜正＞ The hyperpolarization-activated current Ih has been implicated in diverse physiological functions including pacemaking and motor learning. Ih is perhaps best known as cardiac pacemaker current because it is thought that this current constitutes the major component of the spontaneous diastolic depolarization. The increase in heart rate following β-adrenergic stimulation has been attributed to cAMP-mediated enhancement of the current. Ih is generated by four HCN channel genes. As HCN4 constitutes the predominant HCN isoform in the sinoatrial node, we tried to determine the function of this channel by generating HCN4-deficient mice. Global knockout of HCN4 results in embryonic lethality. Hence, we used a ligand-inducible Cre recombinase to delete HCN4 in a temporally controlled manner. We demonstrate that HCN4 generates the main part of Ih in sinoatrial node cells. Adult mice lacking HCN4 in the cardiac conduction system display repetitive asystolic phases. However, the mutants can increase their heart rate during sympathetic stimulation. These results indicate that HCN4 is necessary for maintaining a regular cardiac rhythm especially in the transition phase from an increased to basal heart rate.

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Light(Science & Applications) 2020年第1期9卷 1340-1350页

作者： Matthias Blaicher Muhammad Rodlin Billah Juned Kemal Tobias Hoose Pablo Marin-Palomo Andreas hofmann Yasar Kutuvantavida Clemens Kieninger Philipp-Immanuel Dietrich Matthias Lauermann stefan Wolf Ute Troppenz Martin Moehrle Florian Merget Sebastian Skacel Jeremy Witzens Sebastian Randel Wolfgang Freude Christian Koos Institute of Photonics and Quantum Electronics(IPQ) Karlsruhe Institute of Technology(KIT)Engesserstraße 576131 KarlsruheGermany Institute for Microstructure Technology(IMT) KITHermann-von-Helmholtz-Platz 176344 Eggenstein-LeopoldshafenGermany Institute for Automation and Applied Informatics(IAI) KITHermann-von-Helmholtz-Platz 176344 Eggenstein-LeopoldshafenGermany Vanguard Automation GmbH Gablonzer StraBe 1076185 KarlsruheGermany Fraunhofer Institute for Telecommunications Heinrich Hertz Institute(HHI)Einsteinufer 3710587 BerlinGermany Institute of Integrated Photonics(IPH) RWTH AachenSommerfeldstraße 18/2452074 AachenGermany

Three-dimensional(3D)nano-printing of freeform optical waveguides,also referred to as photonic wire bonding,allows for efficient coupling between photonic chips and can greatly simplify optical system *** a key advantage,the shape and the trajectory of photonic wire bonds can be adapted to the mode-field profiles and the positions of the chips,thereby offering an attractive alternative to conventional optical assembly techniques that rely on technically complex and costly high-precision ***,while the fundamental advantages of the photonic wire bonding concept have been shown in proof-of-concept experiments,it has so far been unclear whether the technique can also be leveraged for practically relevant use cases with stringent reproducibility and reliability *** this paper,we demonstrate optical communication engines that rely on photonic wire bonding for connecting arrays of silicon photonic modulators to InP lasers and single-mode *** a first experiment,we show an eight-channel transmitter offering an aggregate line rate of 448 Gbit/s by low-complexity intensity modulation.A second experiment is dedicated to a four-channel coherent transmitter,operating at a net data rate of 732.7 Gbit/s-a record for coherent silicon photonic transmitters with co-packaged *** dedicated test chips,we further demonstrate automated mass production of photonic wire bonds with insertion losses of(0.7±0.15)dB,and we show their resilience in environmental-stability tests and at high optical *** results might form the basis for simplified assembly of advanced photonic multi-chip systems that combine the distinct advantages of different integration platforms.

关键词： communication lithography bonding

Influence of Plasmon Excitations in Au Nanoparticles upon Fluorescence and Photostability of Photosynthetic Complexes

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Optics and Photonics Journal 2013年第1期3卷 1-7页

作者： Bartosz Krajnik Nikodem Czechowski D.Piatkowski Sebastian Mackowski Eckhard hofmann stefan Pichler Wolfgang Heiss Institute of Physics Faculty of PhysicsAstronomy and InformaticsNicolaus Copernicus UniversityTorunPoland Department of Biology and Biotechnology Ruhr-University BochumBochumGermany Institut fur Halbleiter-und Festkorperphysik Universitat LinzLinzAustria

Fluorescence spectroscopy is applied to study the influence of plasmon excitations in spherical Au nanoparticles on the optical properties of chlorophyll-containing light-harvesting complexes. The separation between the two nanostructures is controlled via silica layer with varied thickness. We observe strong increase of the emission intensity for a 12- nm-thick spacer and the increase is accompanied with shortening of the fluorescence lifetime, which allows us to separate contributions of absorption and emission rate enhancement. At the same time we find an increase of photobleaching. These findings are interpreted as a result of spectral overlap between plasmon resonance and chlorophyll fluorescence.

关键词： Plasmonics Fluorescence Photosynthesis

N-acetylcyteine and flavonoid rich diet:The protective effect of 15 different antioxidants on cigarette smoke-damaged primary human osteoblasts

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Advances in Bioscience and Biotechnology 2012年第8期3卷 1129-1139页

作者： Sabrina Ehnert stefan Dobele Karl Friedrich Braun Britta Burkhardt Valeska hofmann Mario Hausmann Jose Tomas Egana Ulrich Stockle Thomas Freude Andreas Klaus Nussler Department of Traumatology Eberhard Karls Universitat TübingenTübingenGermany Department of Traumatology MRITechnische Universitat MünchenMünchenGermany Department of Plastic Surgery and Hand Surgery Technische Universitat MünchenMünchenGermany FONDAP Center for Genome Regulation Facultad de CienciasUniversidad de ChileSantiagoChile

Cigarette consumption increases oxidative stress in many organs. Increased oxidative stress harms bone cells, which negatively affects bone-matter and -stability. This leads to an increased fracture risk and delayed fracture healing in smokers. A supporting therapy with antioxidants could be of great benefit for surgeons dealing with delayed fracture healing due to increased oxidative stress. In this article we complement and compare our published data with hitherto unpublished data and show the protective effect of 15 different antioxidants on cigarette smoke induced damage in primary human osteoblasts. Exposure to cigarette smoke medium (CSM) rapidly induces formation of ROS in osteoblasts in a concentration- and time-dependent manner. Massive cell damage is seen already after 4 h (EC50 ≈ 0.75 OD320). Pre-, co- and post-incubation with the different antioxidants reduces the formation of ROS and consequently improves the viability of the CSM exposed osteoblasts. Small compounds, e.g. N-acetylcysteine, proved highly effective if pre- or co-incubated before exposure to the CSM. Thus, they are good candidates for acute therapy support as they can be administered in high doses. However, our data suggest that a balanced daily diet could lead to an accumulation of various natural antioxidants (flavonoids) that effectively protect osteoblasts from oxidative stress-induced damage in all three settings investigated. Together with their partly phytoestrogenic properties this may even abate alterations in bone and thus reduce fracture risk on the long run.

关键词： Cigarette Smoke Osteoblasts Oxidative Stress N-Acetylcysteine Flavonoids

Tip-and Laser-based 3D Nanofabrication in Extended Macroscopic Working Areas

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Nanomanufacturing and Metrology 2021年第3期4卷 132-148页

作者： Ingo Ortlepp Thomas Frohlich Roland FuBl Johann Reger Christoph Schaffel stefan Sinzinger Steffen Strehle ReneTheska Lena Zentner Jens-Peter Zollner Ivo WRangelow Carsten Reinhardt Tino Hausotte Xinrui Cao Oliver Dannberg Florian Fern David Fischer Stephan Gorges Martin hofmann Johannes Kirchner Andreas Meister Taras Sasiuk Ralf Schienbein Shraddha Supreeti Laura Mohr-Weidenfeller Christoph Weise Christoph Reuter Jaqueline Stauffenberg Eberhard Manske Institute of Process Measurement and Sensor Technology Technische Universitat IlmenauEhrenbergstrasse 2998693 IlmenauGermany Control Engineering Group Technische Universitat IlmenauIlmenauGermany Optical Engineering Group.Technische Universitat Ilmenau IlmenauGermany Microsystems Technology Group.Technische Universitat Ilmenau IlmenauGermany Precision Engineering Group.Technische Universitat Ilmenau IlmenauGermany Compliant Systems Group Technische Universitat IlmenauIlmenauGermany Micro-and Nanoelectronic Systems Group Technische Universitat IlmenauIlmenauGermany Nanoscale Systems Group.Technische Universitat Ilmenau IlmenauGermany Division for Research Service and Technology Transfer Technische Universitat IlmenauIlmenauGermany Electronics Technology Group.Technische Universitat Ilmenau IlmenauGermany IMMS Institut flir Mikroelektronik-und Mechatronik-Systeme Gemeinniitzige GmbH(IMMS GmbH) IlmenauGermany Fachgebiet Technische Physik City University of Applied SciencesBremenGermany Lehrstuhl fiir Fertigungsmesstechnik Friedrich-Alexander-U niversitat(FAU)Erlangen-NiirnbergGermany JUMO GmbH&Co.KG FuldaGermany Asphericon GmbH JenaGermany

The field of optical lithography is subject to intense research and has gained enormous ***,the effort necessary for creating structures at the size of 20 nm and below is considerable using conventional *** effort and the resulting financial requirements can only be tackled by few global companies and thus a paradigm change for the semiconductor industry is conceivable:custom design and solutions for specific applications will dominate future development(Fritze in:Panning EM,Liddle JA(eds)Novel patterning *** society for optics and ***,Bellingham,***://***/10.1117/12.2593229).For this reason,new aspects arise for future lithography,which is why enormous effort has been directed to the development of alternative fabrication ***,the technologies emerging from this process,which are promising for coping with the current resolution and accuracy challenges,are only demonstrated as a proof-of-concept on a lab scale of several square *** scale is not adequate for the requirements of modern lithography;therefore,there is the need for new and alternative cross-scale solutions to further advance the possibilities of unconventional *** challenges arise because of the technical progress in various other fields,realizing new and unique functionalities based on nanoscale effects,e.g.,in nanophotonics,quantum computing,energy harvesting,and life *** platforms for basic research in the field of scale-spanning nanomeasuring and nanofabrication are necessary for these tasks,which are available at the Technische Universitiit Ilmenau in the form of nanopositioning and nanomeasuring(NPM)*** this equipment,the limits of technical structurability are explored for high-performance tip-based and laser-based processes for enabling real 3D nanofabrication with the highest precision in an adequate working range of several thousand cubic millimete

关键词： Nanomeasuring Nanopositioning Nanomanufacturing Scale-spanning Tip-based Laser-based Nanofabrication