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  • Birk, Udo (2017): Super-Resolution Microscopy. A Practical Guide. Weinheim, Germany: Wiley-VCH

    Abstract: This unique book on super-resolution microscopy techniques presents comparative, in-depth analyses of the strengths and weaknesses of the individual approaches. It was written for non-experts who need to understand the principles of super-resolution or who wish to use recently commercialized instruments as well as for professionals who plan to realize novel microscopic devices. Explaining the practical requirements in terms of hardware, software and sample preparation, the book offers a wealth of hands-on tips and practical tricks to get a setup running, provides invaluable help and support for successful data acquisition and specific advice in the context of data analysis and visualization. Furthermore, it addresses a wide array of transdisciplinary fields of applications. The author begins by outlining the joint efforts that have led to achieving super-resolution microscopy combining advances in single-molecule photo-physics, fluorophore design and fluorescent labeling, instrument design and software development. The following chapters depict and compare current main standard techniques such as structured illumination microscopy, single-molecule localization, stimulated emission depletion microscopy and multi-scale imaging including light-sheet and expansion microscopy. For each individual approach the experimental setups are introduced, the imaging protocols are provided and the various applications illustrated. The book concludes with a discussion of future challenges addressing issues of routine applications and further commercialization of the available methods. Guiding users in how to make choices for the design of their own experiments from scratch to promising application, this one-stop resource is intended for researchers in the applied sciences, from chemistry to biology and medicine to physics and engineering.

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  • Studer, Bruno (2010): Netzwerkmanagement und Netzwerksicherheit. Ein Kompaktkurs für Praxis und Lehre. Zürich: vdf Hochschulverlag AG an der ETH Zürich (Vdf Praxis und Lehre. Informatik)

    Abstract: Im Zeitalter der Globalisierung wird Kommunikations- und Informationsmanagement immer wichtiger – und doch bestehen gerade hier enorme Gefahrenquellen für Unternehmen und Privatpersonen. Mit zunehmender Vernetzung steigt die Gefahr, dass in die komplexen Kommunikationssysteme eingedrungen und grosser Schaden angerichtet wird. Neben speziellen Sicherheitssystemen wie Firewalls oder Verschlüsselungsprogrammen sorgt vor allem ein gutes Netzwerkmanagement dafür, dass weniger Sicherheitslecks entstehen bzw. diese rascher behoben werden können. Hinzu kommt, dass der umfassende und räumlich oft weit verstreute Arbeitsaufwand dadurch optimiert wird. "Netzwerkmanagement und Netzwerksicherheit" bietet nicht nur einen praxisnahen Überblick zu den Vorzügen der speziellen Managementmodelle (SNMP, TMN, Java-Management) sowie zu wichtigen Aspekten des Service-Managements (ITIL); es werden vor allem die möglichen Bedrohungen für die IT-Sicherheit aufgezeigt – und wie man ihnen entgegenwirkt. Dieser Kompaktkurs richtet sich an Studierende und Praktiker gleichermassen. Übersichtlich und leicht verständlich zeigt der Autor auf, worauf man bei der IT-Sicherheit in Firmen, aber auch im privaten Bereich achten muss – und wie man sie oft schon mit kleinen Mitteln optimieren kann.

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  • Hofstetter, Rolf; Wenk, Bruno (2011) : Freies WLAN in den Alpen In: Semar, Wolfgang: Informationsgesellschaft und Infrastrukturpolitik im Alpenraum: Arge Alp Tagung, 23.-24. September 2010, Chur. Hochschule für Technik und Wirtschaft HTW Chur. Schweizerisches Institut für Informationswissenschaft: Chur (Churer Schriften zur Informationswissenschaft. Arbeitsbereich Informationswissenschaft), S. 34-38. Online verfügbar unter https://www.fhgr.ch/fhgr/angewandte-zukunftstechnologien/schweizerisches-institut-fuer-informationswissenschaft-sii/publikationen/churer-schriften/, zuletzt geprüft am 18.12.2020

     

    Abstract: Zwischen den Agglomerationen und Randgebieten besteht bezüglich der mobilen Zugänge offensichtlich ein digitaler Graben, der mit freien WLAN-Zugängen beseitigt werden kann. Freie WLAN-Zugänge sind nichts Neues. Es gibt heute schon Restaurations- und Hotelbetriebe sowie Tourismusorte, welche sich mit dem freien WLAN-Zugang einen Wettbewerbsvorteil sichern.

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  • Brunner, Lars; Salvator, Mario; Roebrock, Philipp; Birk, Udo (2021) : Chess recognition using 3D patterned illumination camera In: Osten, Wolfgang; Nikolaev, Dmitry P.; Zhou, Jianhong (Hg.): Thirteenth International Conference on Machine Vision (ICMV 2020): Proceedings: International Conference on Machine Vision (ICMV): Rom, 2. - 6. November. SPIE The international society for optics and photonics (Proceedings of SPIE), S. 520-527

    DOI: https://doi.org/10.1117/12.2587054 

    Abstract: Computer Vision has been applied to augment traditional board games such as Chess for a number of reasons. While augmented reality enhances the gaming experience, the required additional hardware (e.g. head gear) is still not widely accepted in everyday leisure activities, and therefore, camera based methods have been developed to interface the computer with the real-life chess board. However, traditional 2D camera approaches suffer from ill-defined environmental conditions (lighting, viewing angle) and are therefore severely limited in their application. To answer this issue, we have incorporated a consumer-grade depth camera based on patterned illumination. We could show that in combination with traditional 2D color images, the recognition of chess pieces is made easier, which allows seamless integration of the real-life chess pieces with the computer program. Our method uses a fusion approach from depth and RGB camera data and is suitable for two distant players to play against each other, using two physical sets of chess.

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  • Komm, Dennis; Hauser-Ehninger, Ulrich; Matter, Bernhard; Staub, Jacqueline; Trachsler, Nicole (2021) : Computational Thinking in Small Packages In: Kori, Külli; Laanpere, Mart (Hg.): Informatics in Schools: Engaging Learners in Computational Thinking: Proceedings: 13th International Conference on Informatics in Schools: Situation, Evolution and Perspectives (ISSEP): Tallinn, 16. - 18. November 2020: Cham: Springer (Lecture Notes in Computer Science), S. 170-181

    DOI: https://doi.org/10.1007/978-3-030-63212-0_14 

    Abstract: This article describes an approach to foster computational thinking in different school subjects. Our approach includes several teaching units (packages) that are self-contained and have been designed for university courses attended by prospective and graduate primary and secondary school teachers. Around 30 packages have been designed so far and together cover eight aspects of computational thinking in six different subjects. In this report, some examples are sketched out together with the experiences gathered.

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  • Merbold, Hannes; Iten, Marc-Alexander; Catregn, Gion-Pol (2020) : Multispectral Time-of-Flight Range Imaging. Towards a 3.5 D Camera: Imaging and Applied Optics: Proceedings: Imaging and Applied Optics Congress: Online, 22. - 26. Juni: Washington: Optica

    Abstract: Time-of-flight cameras with sequenced multi-wavelength illumination or swing-in bandpass filters allow recording three spatial dimensions as well as a limited number of spectral data points.

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  • Birk, Udo; Roebrock, Philipp (2018) : User-position aware adaptive display of 3D data without additional stereoscopic hardware In: Verikas, Antanas; Nikolaev, Dmitry P.; Radeva, Petia; Zhou, Jianhong (Hg.): Eleventh International Conference on Machine Vision (ICMV 2018): Proceedings: International Conference on Machine Vision (ICMV): München, 1. - 3. November. SPIE The international society for optics and photonics (Proceedings of SPIE). Online verfügbar unter https://doi.org/10.1117/12.2522678, zuletzt geprüft am 14.02.2020

     

    Abstract: Stereoscopic vision modules have seen limited success in both engineering and consumer world, due to the required additional hardware (image acquisition, Virtual Reality headsets, 3D glasses). In the last years, especially the gaming and education sectors have benefited from such specialized headgear, providing virtual or augmented reality. However, many other industrial and biomedical applications such as e.g. computer aided design (CAD) or tomographic data display, so far have not fully exploited the increased 3D rendering capabilities of present-day computer hardware. We present an approach to use standard desktop PC hardware (monitor and webcam) to display user-position aware projections of 3D data without additional headgear. The user position is detected from webcam images, and the rendered 3D data (i.e. the view) is adjusted to match the corresponding user position, resulting in a quasi virtual reality rendering, albeit without the 3D effect of proper 3D head-gear. The approach has many applications from medical imaging, to construction and CAD, to architecture, to exhibitions, arts and performances. Depending on the user location, i.e. the detected head position, the data is rendered differently to attribute for the user view angle (zoom) and direction. As the user moves his or her head in front of the monitor, different features of the rendered object become visible. As the user moves closer to the screen, the view angle of the rendered data is decreased, resulting in a zoomed-in version of the rendered object.

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  • Merbold, Hannes; Catregn, Gion-Pol; Leutenegger, Tobias (2018) : Time-of-flight range imaging for underwater applications In: Soskind, Yakov G.: Photonic Instrumentation Engineering V: Proceedings: SPIE Photonics West: San Francisco. SPIE The international society for optics and photonics (Proceedings of SPIE). Online verfügbar unter https://doi.org/10.1117/12.2283476, zuletzt geprüft am 21.02.2020

     

    Abstract: Precise and low-cost range imaging in underwater settings with object distances on the meter level is demonstrated. This is addressed through silicon-based time-of-flight (TOF) cameras operated with light emitting diodes (LEDs) at visible, rather than near-IR wavelengths. We find that the attainable performance depends on a variety of parameters, such as the wavelength dependent absorption of water, the emitted optical power and response times of the LEDs, or the spectral sensitivity of the TOF chip. An in-depth analysis of the interplay between the different parameters is given and the performance of underwater TOF imaging using different visible illumination wavelengths is analyzed.

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  • Merbold, Hannes (2017) : Spatiotemporal imaging of THz wave propagation: Polaritonics versus near-field imaging In: IEEE: Proceedings of the 16th Workshop on Information Optics: Workshop on Information Optics (WIO): Interlaken. EPFL, Nanophotonics and Metrology Laboratory NAM, S. 1-3. Online verfügbar unter https://doi.org/10.1109/WIO.2017.8038178, zuletzt geprüft am 21.02.2020

    DOI: https://doi.org/10.1109/WIO.2017.8038178 

    Abstract: Two recently developed methods that allow visualizing the interaction of THz radiation with arbitrary structures, namely polaritonics and near-field imaging, are reviewed and compared. THz polaritonics, which relies on complex amplified laser systems, allows single-shot image acquisition in a plane perpendicular to the structures. THz near-field imaging, on the other hand, requires only femtosecond oscillators but is a slower raster scanning technique providing images parallel to the structure plane.

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  • Geilinger, Eva; Janett, Patrik; Gasser, Stefan; Sivitos, Stamatis; Zuloaga, Francisco; Bush, Eric (2015) : Luminaire efficiency. What mandatory and voluntary labels achieve, and what they should achieve in the future In: Luca, Andrea de; Bertoldi, Paolo (Hg.): Proceedings of the 8th international conference on energy efficiency in domestic appliances and lighting: Re-edition: EEDAL: Luzern, 26. August, S. 1146-1158. Online verfügbar unter 10.2790/012477, zuletzt geprüft am 28.02.2020

     

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  • Leutenegger, Tobias; Studer, Bruno (2015) : First Swiss bachelor in Photonics In: Cormier, Eric; Sarger, Laurent (Hg.): Education and Training in Optics and Photonics: Proceedings: ETOP: Bordeaux, 25. Juni - 2. Juli. SPIE The international society for optics and photonics (Proceedings of SPIE). Online verfügbar unter https://doi.org/10.1117/12.2223216, zuletzt geprüft am 28.02.2020

     

    Abstract: Swissmem, the Swiss association of mechanical and electrical engineering industries, founded a new photonics group in 2013. This reflects the importance of this key technology for Switzerland. Swissmem requested from the Swiss Universities of Applied Sciences to introduce a new bachelor program to fulfill the increasing demand of the Swiss industry of young academics in the field of photonics. Optech Consulting is investigating the Swiss photonics market since many years on behalf of Swissphotonics, the Swiss national thematic network for photonics. The study concluded that the total production volume of the Swiss photonics industry in the year 2013 was 3 billion Swiss francs and a slight growth is expected for 2014. The University of Applied Science HTW Chur is located in the Eastern part of Switzerland. This area of the Rhine valley is a technology cluster of innovative companies in the field of optics and electronics. The industry is growing and the R&D departments of the worldwide active companies are lacking well-educated photonics engineers. The HTW Chur is dedicated to establish the first Swiss bachelor in Photonics. Supported by strong industrial players and an excellent network, the HTW Chur developed different job descriptions and a complete curriculum, which reflect the needs of the Swiss photonics industry. Almost 60% of the ECTS of this national degree program are assigned to photonics specific courses and the practical projects are organized in close collaboration with the photonics industry. Curriculum, job descriptions and the industrial needs will be discussed in detail in this paper.

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  • Weichselbraun, Albert; Süsstrunk, Norman (2015) : Optimizing Dependency Parsing Throughput In: Fred, Ana; Dietz, Jan; Aveiro, David; Liu, Kecheng; Filipe, Joaquim (Hg.): Proceedings of the 7th International Joint Conference on Knowledge Discovery, Knowledge Engineering and Knowledge Management, 1: Joint Conference on Knowledge Discovery, Knowledge Engineering and Knowledge Management: Lissabon, 12. - 14. November: 3, S. 511-516. Online verfügbar unter 10.5220/0005638905110516, zuletzt geprüft am 28.02.2020

     

    Abstract: Dependency parsing is considered a key technology for improving information extraction tasks. Research indicates that dependency parsers spend more than 95% of their total runtime on feature computations. Based on this insight, this paper investigates the potential of improving parsing throughput by designing feature representations which are optimized for combining single features to more complex feature templates and by optimizing parser constraints. Applying these techniques to MDParser increased its throughput four fold, yielding Syntactic Parser, a dependency parser that outperforms comparable approaches by factor 25 to 400.

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  • Merbold, Hannes; Bitzer, Andreas; Carbone, Fabrizio; Murk, Axel; Wallauer, Jan; Walther, Markus; Feurer, Thomas (2012) : Adjusting the functionality of terahertz split-ring resonators through geometry In: Betz, Markus; Elezzabi, Abdulhakem Y.; Song, Jin-Joo; Tsen, Kong-Thon (Hg.): Ultrafast Phenomena and Nanophotonics XVI: SPIE OPTO: San Francisco, California, USA, 21.-26. Januar: SPIE. Digital Library (SPIE Proceedings)

    DOI: https://doi.org/10.1117/12.908107 

    Abstract: We examine planar double split-ring resonators (SRRs) consisting of two concentric rings with either opposite, similar, or asymmetric gap orientation. Depending on the geometry we observe resonance hybridization, metamaterial induced transparency, or the excitation of dark resonances. These properties can be used for SRR based sensing applications, to realize strongly dispersive behavior, or for determining the optical properties of metals. We further find that THz SRRs featuring very narrow gaps on the micro- or nanoscale can provide in-gap enhancement factors of several 10,000, a property particularly useful for the realization of nonlinear THz experiments.

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  • Wenk, Bruno (2010) : Open educational resources (OER) inspire teaching and learning: Educon 2010: Annual Global Engineering Education Conference The Future of Global Learning in Engineering Education: IEEE Educon 2010 Conference: Madrid, 14.-16. April: [Madrid]: UPM, Servicio de Publicaciones, S. 435-441. Online verfügbar unter http://educon-conference.org/educon2010/, zuletzt geprüft am 18.12.2020

     

    Abstract: Open educational resources (OER) can significantly reduce the time required to prepare lectures. The prerequisites are that a desired resource can be found quickly and that its adequacy for the intended purpose can be estimated easily. Eventually, the resource should also be suitable for modification. In the first part we outline the requirements for the sourcing, storing, retrieval and exchange of open educational resources considering technical and legal aspects. In the second part we present a case study focusing on the user level perspective. We describe the searching for a particular OER (an online Moodle tutorial), the analysis of the resource found, its modification and the publishing of the modified resource on a repository.

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  • Bühringer, Maleachi; Berchtold, Jan; Büchel, Melanie; Dold, Claus; Bütikofer, Michael; Feuerstein, Mevina; Fischer, Wolfgang; Bermes, Christian; Siegwart, Roland (2010) : Inspection of high voltage power lines-a new approach In: Tosun, O.; Akin, H. L.; Tokhi, Mohammad Osman; Virk, Gurvinder S. (Hg.): Mobile robotics: Solutions and challenges: Proceedings of the Twelfth International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines: International Conference on Climbing and Walking Robots: Istanbul, 9. - 11. September: 2009. International Conference on Climbing and Walking Robots: Singapore; Hackensack: World Scientific, S. 455-462

    Abstract: This paper presents the "Cable Crawler", a mobile teleoperated robot to inspect high voltage power lines. Its mechanism allows riding on the topmost ground cable of high voltage power lines and crossing a set of mast tips as well as smaller obstacles autonomously and thus is not limited to just move from mast to mast. The robot consists of an aluminium chassis, six propulsion units and two spaces for cameras and other electronic components. Six electrical motors drive independently six rubber-coated rollers, two in a horizontal position to take the weight and four vertical ones. The four vertical rollers are pressed onto the wire by springs, which guarantees slipless propulsion in difficult situations. A Matlab program controls the drives independently. An optical camera is mounted on the prototype, which can rotate 360° and the image can be transmitted wireless to the user's computer monitor. With a mass of 58 kg and only six drives it consequently follows the industry's wish to have a robust, easy to maintain and rather cheap solution. Regarding the fields examined by the robot, the project concentrated on the detection of trees growing into proximity of the wires.

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  • Schafroth, Dario; Bermes, Christian; Bouabdallah, Samir; Siegwart, Roland (2010) : Modeling and System Identification of the muFly Micro Helicopter In: Valavanis, Kimon P.; Beard, Randal; Oh, Paul; Ollero, Aníbal; Piegl, Leslie A.; Shim, Hyunchui (Hg.): Selected papers from the 2nd International Symposium on UAVs, Reno, Nevada, U.S.A. June 8–10, 2009: Reno, 8. - 10. Juni: 2009: Dordrecht; Heidelberg; London; New York: Springer Science+Business Media, S. 27-47

    Abstract: An accurate mathematical model is indispensable for simulation and control of a micro helicopter. The nonlinear model in this work is based on the rigid body motion where all external forces and moments as well as the dynamics of the different hardware elements are discussed and derived in detail. The important model parameters are estimated, measured or identified in an identification process. While most parameters are identified from test bench measurements, the remaining ones are identified on subsystems using the linear prediction error method on real flight data. The good results allow to use the systems for the attitude and altitude controller design.

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  • Birk, Udo; Darrell, Alex; Konstantinidis, Nikos; Ripoll, Jorge (2010) : Correction of Lateral Movement and Spherical Aberrations in Optical Projection Tomography: Proceedings Biomedical Optics and 3-D Imaging: Biomedical Optics 2010: Miami, 11. - 14. April. Biomedical optics and 3-D imaging: Washington, DC: Optica Publishing Group

    Abstract: Non-invasive optical projection tomography (OPT) provides a method to image small animals in-vivo. We present two correction methods for this technique which can be applied after the images have been acquired. The first method allows to reconstruct specimens embedded in media with arbitrary refractive index, and the second method corrects for small movements of the specimens with respect to the detection system. We have tested the correction methods with computer simulated data and with samples of Parhyale hawaiensis embedded in sea water. These post-acquisition corrections prove to be a major step towards routine in-vivo imaging, and provide 3D analyses of OPT data which can not be rendered using standard reconstruction methods.

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  • Bermes, Christian; Bouabdallah, Samir; Schafroth, Dario; Siegwart, Roland (2009) : Design Parameters for Coaxial Rotary Wing MAVs with Passive Roll and Pitch Stability: 65th American Helicopter Society International Annual Forum: Volume 1 of 3: Grapevine, 27. - 29. Mai: Alexandria

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  • Bermes, Christian; Schafroth, Dario; Bouabdallah, Samir; Siegwart, Roland (2009) : Modular Simulation Model for Coaxial Rotary Wing MAVs: Proceedings of the 2nd International Symposium on Unmanned Aerial Vehicles 2009: 2nd International Symposium on Unmanned Aerial Vehicles 2009: Reno, 8. - 10. Juni

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  • Öttl, Sonja; Pfister, Joachim; Stettler, Niklaus; Studer, Markus; Wenk, Bruno (2008) : Garden Memory Goes Public. Ein ontologiebasiertes Informationssystem zur Gartendenkmalpflege In: Ockenfeld, Marlies: Verfügbarkeit von Informationen: 30. Online-Tagung der DGI, 60. Jahrestagung der DGI ; Frankfurt am Main, 15. bis 17. Oktober 2008 ; proceedings: Online-Tagung der DGI; Jahrestagung der DGI: Frankfurt am Main, 15.-17. Oktober. Deutsche Gesellschaft für Informationswissenschaft und Informationspraxis: Frankfurt am Main: Deutsche Gesellschaft für Informationswissenschaft und Informationspraxis (Tagungen der Deutschen Gesellschaft für Informationswissenschaft und Informationspraxis), S. 247-257

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  • Bermes, Christian; Leutenegger, Stefan; Bouabdallah, Samir; Schafroth, Dario; Siegwart, Roland (2008) : New design of the steering mechanism for a mini coaxial helicopter: EE International Workshop on Intelligent Robots and Systems (IROS): International Conference on Intelligent Robots and Systems: Nice, 22. - 26. September, S. 1236-1241

    Abstract: Whenever the realization of a swash plate mechanism is not feasible (e.g. due to miniaturization limitations), center of gravity steering is an interesting alternative to swash plate steering. We present an approach to describe the dynamic behavior of a coaxial micro helicopter steered by a center of gravity shifting mechanism. The mechanical design of an existing system is improved to increase mechanical robustness and steering quality. In parallel, a simulation model is developed and implemented. It is used to estimate the system response to steering inputs, and to compare center of gravity to swash plate steering. Experimental flight results show an improvement of the helicopter performance due to the mechanical redesign.

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  • Bermes, Christian; Leutenegger, Stefan; Bouabdallah, Samir; Siegwart, Roland (2008) : Design and Comparison of a Steering Mechanism for an Autonomous Coaxial Indoor Helicopter: Proceedings of The ASME International Symposium on Flexible Automation (ISFA): The ASME International Symposium on Flexible Automation (ISFA): Atlanta, 23. - 26. Juni

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  • Bermes, Christian; Sartori, Kevin; Schafroth, Dario; Bouabdallah, Samir; Siegwart, Roland (2008) : Control of a coaxial helicopter with center of gravity steering: Workshop Proceedings of SIMPAR 2008: International Conference on Simulation, Modeling, and Programming for Autonomous Robots: Venedig, 3. - 4. November, S. 492-500

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  • Bermes, Christian; Jacobs, Laurence J.; Kim, Jin-Yeon; Qu, Jianmin (2007) : Cumulative Second Harmonic Generation in Lamb Waves for the Detection of Material Nonlinearities In: Thompson, Donald O.; Chimenti, Dale E. (Hg.): Review of progress in quantitative nondestructive evaluation: Portland, 30. Juli - 4. August: 2006 (AIP conference proceedings), S. 177-184. Online verfügbar unter https://doi.org/10.1063/1.2717971, zuletzt geprüft am 06.05.2023

     

    Abstract: An understanding of the generation of higher harmonics in Lamb waves is of critical importance for applications such as remaining life prediction of plate‐like structural components. The objective of this work is to use nonlinear Lamb waves to experimentally investigate inherent material nonlinearities in aluminum plates. These nonlinearities, e.g. lattice anharmonicities, precipitates or vacancies, cause higher harmonics to form in propagating Lamb waves.The amplitudes of the higher harmonics increase with increasing propagation distance due to the accumulation of nonlinearity while the Lamb wavetravels along its path. Special focus is laid on the second harmonic, and a relative nonlinearity parameter is defined as a function of the fundamental and second harmonic amplitude. The experimental setup uses an ultrasonic transducer and a wedge for the Lamb wave generation, and laser interferometryfor detection. The experimentally measured Lamb wave signals are processed with a short‐time Fourier transformation (STFT), which yields the amplitudes at different frequencies as functions of time, allowing the observation of the nonlinear behavior of the material.The increase of the relative nonlinearity parameter with propagation distance as an indicator of cumulative second harmonic generation is shown in the results for the alloy aluminum 1100‐H14.

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  • Bermes, Christian; Schafroth, Dario; Bouabdallah, Samir; Siegwart, Roland (2007) : Aerodynamic Optimization, Dynamic Modeling and Overall Prototype Design for the muFly Autonomous Micro-Helicopter: International Symposium on Flying Insects and Robots: Flying Insects and Robots: Monte Verità, 12. - 17. August, S. 9-10

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  • Bouabdallah, Samir; Bermes, Christian; Schafroth, Dario; Siegwart, Roland (2007) : MuFly Project. The First Steps: International Symposium on Flying Insects and Robots: Flying Insects and Robots: Monte Verità, 12. - 17. August, S. 13-14

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  • Fenz, Susanne; Mathée, H.; Kreth, Gregor; Baddeley, David; Weiland, Y.; Schwarz-Finsterle, Jutta; Cremer, Christoph; Birk, Udo (2007) : Two-color intranuclear distance measurements of gene regions in human lymphocytes In: Wilson, Tony; Periasamy, Ammasi (Hg.): Confocal, Multiphoton, and Nonlinear Microscopic Imaging III: European Conference on Biomedical Optics: München, 17. - 21. Juni (SPIE Proceedings)

    DOI: http://proceedings.spiedigitallibrary.org/proceeding.aspx?doi=10.1117/12.727506 

    Abstract: The method of Spectral Precision Distance Microscopy (SPDM) has been used to determine distances between two FISH (Fluorescence-in situ-Hybridization)-labeled gene regions on chromosome 9. To this end we applied methods to correct for chromatic aberrations of the microscope optics alone and also of the sample induced aberrations due to mismatch of the refractive indices. Using a confocal microscope and a threshold based position determination algorithm, positions could be measured with an accuracy of about 65 nm inside of fixed cell nuclei. Distances obtained from the measurements have been verified using a 3D computer model of the cell nucleus. In principle, this SPDM approach could be combined with novel fluorescence microscopes to obtain structural information well below the optical resolution. At present the precision limit of the distance measurements is set by variations of the refractive index throughout the specimens.

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  • Fenz, Susanne; Mathée, Hans; Kreth, Gregor; Baddeley, David; Weiland, Yanina; Schwarz-Finstlerle, J.; Cremer, Christoph; Birk, Udo (2007) : Two-color intranuclear distance measurements of gene regions in human lymphocytes In: Wilson, Tony; Periasamy, Ammasi (Hg.): Confocal, multiphoton, and nonlinear microscopic imaging III: Proceedings of SPIE-OSA Biomedical Optics: European Conference on Biomedical Optics: München, 17. - 21. Juni: Bellingham, Wash.; Washington, D.C.: Optica Publishing Group (Proceedings of SPIE)

    Abstract: The method of Spectral Precision Distance Microscopy (SPDM) has been used to determine distances between two FISH (Fluorescence-in situ-Hybridization)-labeled gene regions on chromosome 9. To this end we applied methods to correct for chromatic aberrations of the microscope optics alone and also of the sample induced aberrations due to mismatch of the refractive indices. Using a confocal microscope and a threshold based position determination algorithm, positions could be measured with an accuracy of about 65 nm inside of fixed cell nuclei. Distances obtained from the measurements have been verified using a 3D computer model of the cell nucleus. In principle, this SPDM approach could be combined with novel fluorescence microscopes to obtain structural information well below the optical resolution. At present the precision limit of the distance measurements is set by variations of the refractive index throughout the specimens.

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  • Birk, Udo; Baddeley, David; Cremer, Christoph (2006) : Local protein/gene density measurements using SMI microscopy In: Gorecki, Christophe; Asundi, Anand K.; Osten, Wolfgang (Hg.): Optical Micro- and Nanometrology in Microsystems Technology: Photonics Europe: Strassburg, 3.-7. April (SPIE Proceedings)

    DOI: http://proceedings.spiedigitallibrary.org/proceeding.aspx?doi=10.1117/12.668023 

    Abstract: Spatially Modulated Illumination (SMI) microscopy was applied to determine changes of the local refractive index at discrete fluorescently labeled sites within the cell nucleus. We present measurements on polymerase II complexes, where we found a variation of the local refractive index of 1.38 - 1.55 (standard deviation interval) throughout the nucleus. This variability is not correlated to the accumulations and the extensions of the polymerase II complexes, which have been determined in a previous experiment.1 Local protein accumulations such as adherent transcriptionally active proteins could possibly contribute to such variations, as could also different compactions of the DNA fiber. Altogether, we present a method to precisely obtain a map of the local refractive index inside of cell nuclei, which provides another contrasting mechanism for visualizing sub cellular structures.

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  • Leutenegger, Tobias; Schlums, Dirk H.; Dual, Jürg (1999) : Structural testing of fatigued structures In: Wereley, Norman M.: Smart Structures and Materials 1999: Smart Structures and Integrated Systems: 1999 Symposium on Smart Structures and Materials: Newport Beach, 1. März (SPIE Proceedings), S. 987-997

    DOI: http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=982238 

    Abstract: The structural responses of beams and tubes is investigated in theory and experiment in order to locate and assess damage in the form of fatigue cracks. Crack length measurements are performed in transversely vibrating beams by determining the resonant frequency, which is stabilized through a phase locked loop. Cracks are initiated and propagate from the notch of the structure which is vibrating at resonance. The frequency in relation to the crack length is modeled including the nonlinearity effect due to closing of the crack. Fatigue tests were also carried out with piezoelectrically excited microstructures.

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  • Öttl, Sonja; Streiff, Daniel; Stettler, Niklaus; Studer, Martin : Aufbau einer Testumgebung zur Ermittlung signifikanter Parameter bei der Ontologieabfrage In: Ockenfeld, Marlies: Semantic Web & Linked Data: Elemente zukünftiger Informationsinfrastrukturen: 62. Jahrestagung der DGI: 1. DGI-Konferenz: Frankfurt am Main, 7.-9. Oktober. Deutsche Gesellschaft für Informationswissenschaft und Informationspraxis, S. 21-32

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  • Schafroth, Dario; Bermes, Christian; Bouabdallah, Samir; Siegwart, Roland : Micro Helicopter Steering: Review and Design for the muFly Project: 2008 IEEE/ASME International Conference on Mechtronic and Embedded Systems and Applications: International Conference on Intelligent Robots and Systems: Beijing, 12. - 15. Oktober: 2008, S. 216-221

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  • Darrell, Alexander; Marias, Kostas; Brady, Michael; Meyer, Heiko; Birk, Udo; Ripoll, Jorge : Noise reduction in fluorescence Optical Projection Tomograph: 2008 IEEE International Workshop on Imaging Systems and Techniques: Chania, 10. - 12. September: 2008

    Abstract: Optical Projection Tomography (OPT) suffers from additive CCD detector noise. This paper investigates the nature of the CCD detector noise for an OPT setup. The CCD detector noise is found to be described well by an intensity dependent zero-mean Gaussian distribution. A method of reducing the effect of noise in fluorescence OPT reconstructions is discussed. The results of the noise reduction are demonstrated using both artificial scenes created with fluorescent microspheres and real auto-fluorescence OPT projections of the cuticle of the amphipod crustacean Parhyale hawaiensis.

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  • Darrell, Alexander; Meyer, H.; Birk, Udo; Marias, Kostas; Brady, Michael; Ripoll, Jorge : Maximum likelihood reconstruction for fluorescence Optical Projection Tomography: 2008 8th IEEE International Conference on BioInformatics and BioEngineering: Athen, 8. - 10. Oktober: 2008

    Abstract: Tomographic reconstruction of fluorescence optical projection tomography (OPT) data is usually performed using the standard filtered back projection (FBP) algorithm. However, there are several physical aspects of fluorescence OPT that pose major challenges for the FBP algorithm. These include blurring, and the fact that for an isotropically emitting point source (or fluorophore), the power received by an objective aperture decreases with the inverse square of the distance to the source. These two effects are shown to result in qualitative and quantitative inaccuracies in fluorescence OPT reconstructions obtained using standard FBP. A model of image formation is developed which includes the effects of isotropic emission and blurring. The model is used to calculate a probabilistic system matrix for use in the maximum likelihood expectation maximisation algorithm, which leads to reconstructions that are both qualitatively superior and quantitatively correct.

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  • Merbold, Hannes; Wahl, Ulrich; Stosky, Steven : Laser-Based Oxygen Monitoring in Waste Incineration Facilities: Benefits and Challenges: Advanced Photonics 2014: Proceedings: Nonlinear Photonics: Barcelona, 27. - 31. Juli: 2015

    Abstract: Oxygen measurements using tunable diode laser absorption spectroscopy were performed at a full scale waste incineration facility. A comparative analysis to a reference method allowed identifying benefits and challenges inherent to the laser method.

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  • van Mechelen, J. L. M.; Kuzmenko, A. B.; Merbold, Hannes : High precision material characterization method using THz spectroscopy: 39th International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz): Tucson, 14. - 19. September: 2014

    Abstract: We propose a novel THz material analysis approach which consists of a combination of a stratified dispersive model, an appropriate measurement configuration and a time-domain based fitting procedure. The measurement configuration is modeled as a stratified system where for each layer the light-matter interaction is realistically described. The method is illustrated for the industrial quality control of (coated) paper sheets and is shown to give highly accurate results in humid air and irrespective of the position of the reference mirror in reflection.

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  • Merbold, Hannes; Weber, Yannik; Murk, Axel; Feurer, Thomas : Sensing the Dielectric Properties of Metals at THz Frequencies Using Inverse Symmetry Broken Metamaterial: Advanced Photonics 2015: Proceedings: Optical Sensors: Boston, 27. Juni - 1. Juli: 2015

    Abstract: Positive and inverse, asymmetric, double split-ring resonator structures are analyzed experimentally and numerically. The structures exhibit very sharp dark resonances which allow probing the dielectric properties of metals at THz frequencies.

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  • Eberhart, Martin F.; Löhle, Stefan; Zander, Fabian; Merbold, Hannes; Murk, Axel; Merli, Stefan : Electromagnetic Wave Transmission through Lightweight Carbon Phenolic Ablator. Microwave to Infrared Frequencies: 46th AIAA Thermophysics Conference: Washington, 13. - 17. Juni: 2016

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  • van Mechelen, J. L. M.; Maas, D. J. H. C.; Merbold, Hannes : Paper sheet parameter determination using terahertz spectroscopy: 41st International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz): Kopenhagen, 25. - 30. September: 2016

    Abstract: Using THz spectroscopy, we show how to uniquely determine parameters for industrial quality control of paper sheets. We carry out measurements within the industrial setting: no averaging, fast acquisition in ambient conditions, and quasi-real-time analysis. Paper parameters are extracted using a combination of statistical evaluation and physical interpretation of the light-matter interaction. We show that THz spectroscopy offers additional value as compared to currently used industrial sensors.

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  • Merbold, Hannes; Maas, D. J. H. C.; van Mechelen, J. L. M. : Multiparameter sensing of paper sheets using terahertz time-domain spectroscopy. Caliper, fiber orientation, moisture, and the role of spatial inhomogeneity: 2016 IEEE SENSORS: Orlando, 10. Oktober - 3. November: 2016, S. 1-3
  • Jacobson, Christopher David; Capol, Corsin; Bügler, Tanja; Staudt, Yves; Derungs, Robin (2023) : Einsatz und Potenzial künstlicher Intelligenzim Tourismus. Verhaltensprogrnosen In: Bieger, Thomas; Beritelli, Pietro; Laesser, Christian (Hg.): Alpiner Tourismus in disruptiven Zeiten: Berlin: Erich Schmidt Verlag (Schweizer Jahrbuch für Tourismus), S. 265-278

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  • Capol, Corsin; Jacobson, Christopher David; Balestra, Stefano; Bügler, Tanja; Staudt, Yves; Siegrist, Chantal; Iten, Marc-Alexander (2022) : Personalallokation und -planung für das Immobilienmanagement im Tourismus In: Bieger, Thomas; Beritelli, Pietro; Laesser, Christian (Hg.): Krisenbewältigung und digitale Innovationen im alpinen Tourismus: Berlin: Erich Schmidt Verlag (Schweizer Jahrbuch für Tourismus), S. 131-146