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Advanced Solid State Lasers, ASSL 2017

作者： Gottschall, Thomas Meyer, Tobias Jauregui, Cesar Just, Florian Eidam, Tino Schmitt, Michael Popp, Jürgen Limpert, Jens Tünnermann, Andreas Friedrich-Schiller-Universität Jena Institute of Applied Physics Abbe Center of Photonics Albert-Einstein-Str. 15 Jena07745 Germany Friedrich-Schiller-Universität Jena Institute of Physical Chemistry Abbe Center of Photonics Helmholtzweg 4 Jena07743 Germany e.V. Albert-Einstein-Str. 9 Jena07745 Germany Active Fiber Systems GmbH Wildenbruchstr. 15 Jena07745 Germany Fraunhofer Institute for Applied Optics and Precision Engineering Albert-Einstein-Str. 7 Jena07745 Germany

ISBN: (纸本)9780960038077

The term coherent Raman scattering (CRS) summarizes imaging methods that do not only poses inherent 3D sectioning capabilities but also enables chemical sensitive detection of living tissue. Instead of relying on external markers that are potentially changing its behavior, CRS measures the vibration frequencies of the molecular bonds by the means of inelastic scattering known as Raman scattering. Among these techniques, stimulated Raman Scattering (SRS) has the advantage to be background-free but requires an extremely quiet, widely tunable dual-wavelength laser source. Up to now, such features could only be provided by large and sensitive laser systems that limited the used of this imaging modality to specialized laser laboratories. We present a compact all-fiber laser system, which features an optical parametric oscillator (OPO) based on degenerate four-wave mixing (FWM) in an endlessly single-mode photonic-crystal fiber. We employ an all-fiber frequency- and repetition-rate tunable laser in order to enable wideband conversion in the linear OPO cavity arrangement. The signal and idler radiation can be tuned between 764 and 960 nm and 1164 and 1552 nm at 9.5 MHz. Thus, all biochemically relevant Raman shifts between 922 and 3322 cm-1 may be addressed in combination with a secondary output, which is tunable between 1024 and 1052 nm. This ultra-low noise output emits synchronized pulses with twice the repetition rate to enable SRS imaging. We measure the relative intensity noise of this output beam at 9.5 MHz over the tuning range to be between -145 and -148 dBc, which is low enough to enable direct high-speed SRS imaging with a good signal-to-noise ratio without the use of balanced detection. The laser system is computer controlled to access a certain energy differences within one second. Combining FWM based conversion, with all-fiber Yb-based fiber lasers enables the construction of the first automated, turn-key and widely tunable fiber laser. This laser concept cou

关键词： Stimulated Raman scattering

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Molecular engineering of Conjugated Acetylenic Polymers for Efficient Cocatalyst‐free Photoelectrochemical Water Reduction

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Angewandte Chemie 2019年第30期131卷

作者： Hanjun Sun Ibrahim Halil Öner Tao Wang Tao Zhang Oleksandr Selyshchev Christof Neumann Yubin Fu Zhongquan Liao Shunqi Xu Yang Hou Andrey Turchanin Dietrich R. T. Zahn Ehrenfried Zschech Inez M. Weidinger Jian Zhang Xinliang Feng Center for Advancing Electronics Dresden (cfaed) and Department of Chemistry and Food Chemistry Dresden University of Technology Mommsenstrasse 4 01062 Dresden Germany Chair of Electrochemistry Dresden University of Technology 01062 Dresden Germany SUNCAT Center for Interface Science and Catalysis Department of Chemical Engineering Stanford University Stanford CA 94305 USA Semiconductor Physics Chemnitz University of Technology 09126 Chemnitz Germany Institute of Physical Chemistry and Center for Energy and Environmental Chemistry Jena (CEEC Jena) Friedrich Schiller University Jena Lessingstrasse 10 07743 Jena Germany Fraunhofer Institute for Ceramic Technologies and Systems (IKTS) Maria-Reiche-Strasse 2 01109 Dresden Germany Key Laboratory of Biological Engineering of Ministry of Education College of Chemical and Biological Engineering Zhejiang University Hangzhou 310027 China Department of Applied Chemistry School of Applied and Natural Sciences Northwestern Polytechnical University Xi'an 710129 P. R. China

Conjugated polymers featuring tunable band gaps/positions and tailored active centers, are attractive photoelectrode materials for water splitting. However, their exploration falls far behind their inorganic counterparts. Herein, we demonstrate a molecular engineering strategy for the tailoring aromatic units of conjugated acetylenic polymers from benzene‐ to thiophene‐based. The polarized thiophene‐based monomers of conjugated acetylenic polymers can largely extend the light absorption and promote charge separation/transport. The C≡C bonds are activated for catalyzing water reduction. Using on‐surface Glaser polycondensation, as‐fabricated poly(2,5‐diethynylthieno[3,2‐b]thiophene) on commercial Cu foam exhibits a record H 2 ‐evolution photocurrent density of 370 μA cm −2 at 0.3 V vs. reversible hydrogen electrode among current cocatalyst‐free organic photocathodes (1–100 μA cm −2 ). This approach to modulate the optical, charge transfer, and catalytic properties of conjugated polymers paves a critical way toward high‐activity organic photoelectrodes.

关键词： Cokatalysatorfreie Photokathoden Glaser-Polykondensation Konjugierte Polymere Molekulares engineering Wasserstoffentwicklung

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Next generation urban mining - Automated disassembly, separation and recovery of valuable materials from electronic equipment: Overview of R&D approaches and first results of the European project ADIR 9

Next generation urban mining - Automated disassembly, separa...

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9th European Metallurgical Conference, EMC 2017

作者： Noll, R. Ambrosch, R. Bergmann, K. Britten, S. Brumm, H. Chmielarz, A. Connemann, S. Eschen, M. Frank, A. Fricke-Begemann, C. Gehlen, C. Gorewoda, T. Guolo, M. Kurylak, W. Makowe, J. Sellin, G. Siguier, M. Tori, A. Veglia, F. Fraunhofer Institute for Laser Technology Steinbachstr. 15 Aachen52074 Germany Pro Automation GmbH Vienna Austria H.C. Starck GmbH Goslar Germany Instytut Metali Niezelaznych Gliwice Poland Aurubis AG Lünen Germany Laser Analytical Systems and Automation Baesweiler Germany Osai AS Torino Italy Electrocycling GmbH Goslar Germany SAS I-Cube Research Toulouse France Tre Tau Engineering srl Torino Italy

ISBN: (纸本)9783940276735

An overview will be presented on current R&D activities of the European project ADIR - running since 9/2015 - dealing with the automated disassembly, separation and recovery of valuable materials from electronic equipment. Main focus are end-of-life cell phones and printed circuit boards from server and network electronics. To date the material specific recycling is focused on mass stream concepts such as shredder processes and metallurgy to extract the high-value metallic constituents, i.e. copper, gold and silver. However, a series of critical elements cannot be recovered efficiently or is even lost in dust or residual fractions. The goal of ADIR is to demonstrate the feasibility of a key technology for next generation urban mining in the scope of reverse production concepts. An automated disassembly of electronic equipment is worked out to separate and recover valuable materials. The concept is based on image processing, robotic handling, pulsed power technology, 3D laser measurement, real-time laser material identification (to detect materials by laser spectroscopy), laser processing (to selectively unsolder these;to cut off parts of a printed circuit board), and automatic separation into different sorting fractions. A data base is built up providing comprehensive information about physical and chemical features of the items to be treated. A machine concept was worked out being capable to selectively disassemble printed circuit boards and cell phones with short cycle times to gain sorting fractions containing high amounts of valuable materials. Examples are those materials with high economic importance and supply risk such as tantalum, tungsten and neodymium. The various processes for the ADIR demonstrator have been developed recently and will now be implemented in a set of interlinked machines to validate the novel process chain for reverse production. The current state of development will be highlighted. Copyright © European Metallurgical Conference, EMC 2017.

关键词： Pulsed lasers

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Supporting defect causal analysis in practice with cross-company data on causes of requirements engineering problems

arXiv

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arXiv 2017年

作者： Kalinowski, Marcos Curty, Pablo Paes, Aline Spínola, Rodrigo Felderer, Michael Ferreira, Alexandre Fernández, Daniel Méndez Wagner, Stefan Niterói Brazil Fraunhofer Project Center at UFBA Salvador Brazil Institute of Computer Science University of Innsbruck Innsbruck Austria Rio de Janeiro Brazil Software & Systems Engineering Technical University of Munich Munich Germany Institute of Software Technology University of Stuttgart Stuttgart Germany

[Context] Defect Causal Analysis (DCA) represents an efficient practice to improve software processes. While knowledge on cause-effect relations is helpful to support DCA, collecting cause-effect data may require significant effort and time. [Goal] We propose and evaluate a new DCA approach that uses cross-company data to support the practical application of DCA. [Method] We collected cross-company data on causes of requirements engineering problems from 74 Brazilian organizations and built a Bayesian network. Our DCA approach uses the diagnostic inference of the Bayesian network to support DCA sessions. We evaluated our approach by applying a model for technology transfer to industry and conducted three consecutive evaluations: (i) in academia, (ii) with industry representatives of the fraunhofer Project Center at UFBA, and (iii) in an industrial case study at the Brazilian National Development Bank (BNDES). [Results] We received positive feedback in all three evaluations and the cross-company data was considered helpful for determining main causes. [Conclusions] Our results strengthen our confidence in that supporting DCA with cross-company data is promising and should be further investigated. Copyright © 2017, The Authors. All rights reserved.

关键词： Requirements engineering

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Silicon oxynitride microdisk resonators for integrated waveguide coupling 10

Silicon oxynitride microdisk resonators for integrated waveg...

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Smart systems Integration 2016 - 10th International Conference and Exhibition on Integration Issues of Miniaturized systems, SSI 2016

作者： Hett, Thomas Frers, Torsten Widhalm, Alex Berth, Gerhard Hilleringmann, Ulrich Zrenner, Artur Paderborn University Department of Electrical Engineering and Information Technology Paderborn33098 Germany Paderborn University Physics Department Paderborn33098 Germany Fraunhofer Institute for Electronic Nanosystems Department of Advanced Systems Engineering Paderborn33095 Germany

ISBN: (纸本)9783957350404

In this study we present a fully CMOS compatible process for the integration of microdisk resonators which enables a direct coupling to integrated waveguides. As wave guiding material silicon oxynitride is used which is deposited by plasma enhanced chemical vapor deposition. Structures are realized with optical lithography with subsequent reactive ion etching. The characterization is realized by evanescent field coupling of tapered fiber tips to excite whispering gallery modes in the microdisk resonator.

关键词： Whispering gallery modes

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MoveHN-A database to support the development of motion based biosignal processing systems

MoveHN-A database to support the development of motion based...

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European Signal Processing Conference

作者： Andreas Kitzig Stefan Schroter Edwin Naroska Gudrun Stockmanns Reinhard Viga Anton Grabmaier Faculty of Electrical Engineering and Computer Science Ambient Intelligence Laboratory Krefeld Germany Universitat Duisburg-Essen Duisburg Nordrhein-Westfalen DE Department of Electronic Components and Circuits University of Duisburg-Essen Fraunhofer Institute for Microelectronic Circuits and Systems (IMS) Duisburg Germany

In the field of signal processing, pattern recognition and also modeling and simulation, it is often necessary to use large data sets. These allow reliable, independent and test case spanning development of algorithms or even of complete systems. The data is usually taken from existing data sets such as TIMIT for speech recognition and processing or EPILEPSIAE to develop algorithms for epileptic seizure prediction, to give just two examples. Apart from the fact that some of these databases imply a considerable cost factor and thus are not accessible to all research groups, even greater problems arise if no data is available at all. In the field of speech recognition, this problem was solved more or less by creating databases. In the area of biosignal processing with a focus on the functionalization of furniture for care and clinical facilities, there is still a need for large data sets. This was also the case with biomechanical modeling of functionalized furniture, since up to now none or few data on the human movement sequences were available. In order to overcome this deficiency, the following paper presents a new database of motion patterns, which is intended to support the development of algorithms for motion detection as well as modeling biosignal processing. The database can be used and downloaded by any interested researcher for free.

关键词： Hidden Markov models Mathematical model Biological system modeling Databases Medical services Sensor systems

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Development of a low temperature SiC protection layer for post-CMOS MEMS fabrication utilizing vapour release technologies 6

Development of a low temperature SiC protection layer for po...

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6. GMM-Workshops Mikro-Nano-Integration - 6th GMM Workshop on Micro-Nano-Integration

作者： Walk, Christian Chen, Yizhou Vidovic, Nino Kuhl, Andreas Görtz, Michael Vogt, Holger Fraunhofer Institute for Microelectronic Circuits and Systems Finkenstrasse 61 Duisburg47057 Germany Faculty of Electrical Engineering and Information Technology Karlsruhe Univ. of Applied Sciences Germany Department of Microsystems Engineering - IMTEK Univ. of Freiburg Germany

ISBN: (纸本)9783800742783

In post-CMOS processing a sufficient protection of the underlying CMOS structures, while applying sacrificial layer release technologies to realize free standing MEMS, is required. In this work, a low temperature Silicon Carbide (SiC) process at 300◦C by Inductively Coupled Plasma Chemical Vapour Deposition (ICPCVD) has been developed. It has been demonstrated, that SiC provides an excellent protection character in HF/H2O vapour mixtures. For proof of principle, perforated free-standing SiC-structures with a layer thickness of less than 200 nm and 80 µm in diameter have successfully been released in a vapour etch process. © 2016 VDE VERLAG GMBH ∙ Berlin ∙ Offenbach

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Troubleshooting Wireless Coexistence Problems in the Industrial Internet of Things 19

Troubleshooting Wireless Coexistence Problems in the Industr...

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19th IEEE International Conference on Computational Science and engineering, 14th IEEE International Conference on Embedded and Ubiquitous Computing and 15th International Symposium on Distributed Computing and Applications to Business, engineering and Science, CSE-EUC-DCABES 2016

作者： Wetzker, Ulf Splitt, Ingmar Zimmerling, Marco Boano, Carlo Alberto Romer, Kay Fraunhofer Institute for Integrated Circuits Division Engineering of Adaptive Systems Dresden Germany Center for Advancing Electronics Dresden Dresden University of Technology Germany Institute for Technical Informatics Graz University of Technology Austria

ISBN: (纸本)9781509035939

The ever-growing proliferation of wireless devices and technologies used for Internet of Things (IoT) applications, such as patient monitoring, military surveillance, and industrial automation and control, has created an increasing need for methods and tools for connectivity prediction, information flow monitoring, and failure analysis to increase the dependability of the wireless network. Indeed, in a safety-critical Industrial IoT (IIoT) setting, such as a smart factory, harsh signal propagation conditions combined with interference from coexisting radio technologies operating in the same frequency band may lead to poor network performance or even application failures despite precautionary measures. Analyzing and troubleshooting such failures on a large scale is often difficult and time-consuming. In this paper, we share our experience in troubleshooting coexistence problems in operational IIoT networks by reporting on examples that show the possible hurdles in carrying out failure analysis. Our experience motivates the need for a userfriendly, automated failure analysis system, and we outline an architecture of such system that allows to observe multiple communication standards and unknown sources of interference. © 2016 IEEE.

关键词： Internet of things

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engineering activities — considering value creation from a holistic perspective

Engineering activities — considering value creation from a ...

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International Conference on Concurrent Enterprising

作者： Pascal Lünnemann Rainer Stark Wei Min Wang Paola Ibáñez Manteca Department for Virtual Product Creation Fraunhofer-Institute for Production Systems and Design Technology Berlin Germany Department for Machine Tools and Factory Management Technische Universität Berlin Berlin Germany Department of Industrial Engineering IQS-School of Professional & Executive Development Barcelona Spain

Modern value creation is characterized by collaboration of large networks of specialized companies. Due to market requirements and increasing competition, concurrent or simultaneous engineering has become the standard procedure in product development. Still, product development processes often follow the traditionally linear and sequential patterns, allowing for only a narrow scope of iterations. Milestone-driven models are widely used to control and steer such processes. In this article, the authors argue that proper understanding of knowledge flows in development project is an essential aspect to be regarded in design and organization of product development processes. Therefore, a new approach is proposed in this paper which considers the product development process as a set of engineering Activities. Such activities can be seen as instantiations of processes and are the core of any value creation processes. During an experiment a group of students carried out a simple product development project within a controlled environment. The resulting model was then re-evaluated using survey results from a further student experiment. Both results indicate that the activity model can be applied to describe development projects and that it can be used to identify knowledge flows and barriers within development teams.

关键词： Product development Unified modeling language Companies Process control Solid modeling

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100 kHz, femtosecond, 4-10 μm tunable, AgGaSe2-based OPA pumped by a CPA Tm: Fiber laser system

100 kHz, femtosecond, 4-10 μm tunable, AgGaSe2-based OPA pu...

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Advanced Solid State Lasers, ASSL 2017

作者： Baudisch, Matthias Beutler, Marcus Gebhardt, Martin Gaida, Christian Stutzki, Fabian Hädrich, Steffen Herda, Robert Zach, Armin Limpert, Jens Rimke, Ingo APE Angewandte Physik and Elektronik GmbH Haus N Plauener Str. 163-165 BerlinD-13053 Germany Institute of Applied Physics Abbe Center of Photonics Friedrich-Schiller-Universität Jena Albert-Einstein-Str. 15 Jena07745 Germany Helmholtz-Institute Jena Fröbelstieg 3 Jena07743 Germany Active Fiber Systems GmbH Wildenbruchstraße 15 Jena07743 Germany Lochhamer Schlag 19 GräfelfingD-82156 Germany Fraunhofer Institute for Applied Optics and Precision Engineering Albert-Einstein-Str. 7 Jena07745 Germany

We present the first realization of a femtosecond, mid-to-long-infrared tunable OPA driven by a CPA Tm:fiber-laser with 100 kHz repetition rate. The source provides up to 0.75 μJ energy and supports sub-160 fs pulse ... 详细信息

ISBN: (纸本)9780960038077

关键词： Fiber lasers

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