@inproceedings{ChudobaButenwegPfeiffer2003, author = {Chudoba, Rostislav and Butenweg, Christoph and Pfeiffer, Frank}, title = {Textile reinforced concrete. Part I: Process model for collaborative research and development}, series = {Digital proceedings / IKM 2003, proceedings 16th International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering [Elektronische Ressource : 10. - 12. Juni 2003, Weimar] / Bauhaus-Universit{\"a}t Weimar. Ed.: K. G{\"u}rlebeck; L. Hempel; C. K{\"o}nke}, booktitle = {Digital proceedings / IKM 2003, proceedings 16th International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering [Elektronische Ressource : 10. - 12. Juni 2003, Weimar] / Bauhaus-Universit{\"a}t Weimar. Ed.: K. G{\"u}rlebeck; L. Hempel; C. K{\"o}nke}, publisher = {IKM}, address = {Weimar}, organization = {Internationales Kolloquium {\"u}ber Anwendungen der Informatik und Mathematik in Architektur und Bauwesen <16, 2003, Weimar>}, pages = {1 -- 8}, year = {2003}, language = {en} } @inproceedings{ChristianMontagSchubaetal.2018, author = {Christian, Esser and Montag, Tim and Schuba, Marko and Allhof, Manuel}, title = {Future critical infrastructure and security - cyberattacks on charging stations}, series = {31st International Electric Vehicle Symposium \& Exhibition and International Electric Vehicle Technology Conference (EVS31 \& EVTeC 2018)}, booktitle = {31st International Electric Vehicle Symposium \& Exhibition and International Electric Vehicle Technology Conference (EVS31 \& EVTeC 2018)}, publisher = {Society of Automotive Engineers of Japan (JSAE)}, address = {Tokyo}, isbn = {978-1-5108-9157-9}, pages = {665 -- 671}, year = {2018}, language = {en} } @inproceedings{ChristenBarteltKowalskietal.2008, author = {Christen, Marc and Bartelt, Perry and Kowalski, Julia and Stoffel, Lukus}, title = {Calculation of dense snow avalanches in three-dimensional terrain with the numerical simulation programm RAMMS}, series = {Proceedings ISSW 2008 ; International Snow Science Workshop. Whistler 2008}, booktitle = {Proceedings ISSW 2008 ; International Snow Science Workshop. Whistler 2008}, pages = {709 -- 716}, year = {2008}, abstract = {Numerical models have become an essential part of snow avalanche engineering. Recent advances in understanding the rheology of flowing snow and the mechanics of entrainment and deposition have made numerical models more reliable. Coupled with field observations and historical records, they are especially helpful in understanding avalanche flow in complex terrain. However, the application of numerical models poses several new challenges to avalanche engineers. A detailed understanding of the avalanche phenomena is required to specify initial conditions (release zone dimensions and snowcover entrainment rates) as well as the friction parameters, which are no longer based on empirical back-calculations, rather terrain roughness, vegetation and snow properties. In this paper we discuss these problems by presenting the computer model RAMMS, which was specially designed by the SLF as a practical tool for avalanche engineers. RAMMS solves the depth-averaged equations governing avalanche flow with first and second-order numerical solution schemes. A tremendous effort has been invested in the implementation of advanced input and output features. Simulation results are therefore clearly and easily visualized to simplify their interpretation. More importantly, RAMMS has been applied to a series of well-documented avalanches to gauge model performance. In this paper we present the governing differential equations, highlight some of the input and output features of RAMMS and then discuss the simulation of the Gatschiefer avalanche that occurred in April 2008, near Klosters/Monbiel, Switzerland.}, language = {en} } @inproceedings{ChircuCzarneckiFriedmannetal.2023, author = {Chircu, Alina and Czarnecki, Christian and Friedmann, Daniel and Pomaskow, Johanna and Sultanow, Eldar}, title = {Towards a Digital Twin of Society}, series = {Proceedings of the 56th Hawaii International Conference on System Sciences 2023}, booktitle = {Proceedings of the 56th Hawaii International Conference on System Sciences 2023}, publisher = {University of Hawai'i}, address = {Honolulu}, isbn = {978-0-9981331-6-4}, pages = {6748 -- 6757}, year = {2023}, abstract = {This paper describes the potential for developing a digital twin of society- a dynamic model that can be used to observe, analyze, and predict the evolution of various societal aspects. Such a digital twin can help governmental agencies and policy makers in interpreting trends, understanding challenges, and making decisions regarding investments or policies necessary to support societal development and ensure future prosperity. The paper reviews related work regarding the digital twin paradigm and its applications. The paper presents a motivating case study- an analysis of opportunities and challenges faced by the German federal employment agency, Bundesagentur f¨ur Arbeit (BA), proposes solutions using digital twins, and describes initial proofs of concept for such solutions.}, language = {en} } @inproceedings{ChavezBermudezWollert2022, author = {Chavez Bermudez, Victor Francisco and Wollert, J{\"o}rg}, title = {10BASE-T1L industry 4.0 smart switch for field devices based on IO-Link}, series = {2022 IEEE 18th International Conference on Factory Communication Systems (WFCS)}, booktitle = {2022 IEEE 18th International Conference on Factory Communication Systems (WFCS)}, publisher = {IEEE}, isbn = {978-1-6654-1086-1}, doi = {10.1109/WFCS53837.2022.9779176}, pages = {4 Seiten}, year = {2022}, abstract = {The recent amendment to the Ethernet physical layer known as the IEEE 802.3cg specification, allows to connect devices up to a distance of one kilometer and delivers a maximum of 60 watts of power over a twisted pair of wires. This new standard, also known as 10BASE-TIL, promises to overcome the limits of current physical layers used for field devices and bring them a step closer to Ethernet-based applications. The main advantage of 10BASE- TIL is that it can deliver power and data over the same line over a long distance, where traditional solutions (e.g., CAN, IO-Link, HART) fall short and cannot match its 10 Mbps bandwidth. Due to its recentness, IOBASE- TIL is still not integrated into field devices and it has been less than two years since silicon manufacturers released the first Ethernet-PHY chips. In this paper, we present a design proposal on how field devices could be integrated into a IOBASE-TIL smart switch that allows plug-and-play connectivity for sensors and actuators and is compliant with the Industry 4.0 vision. Instead of presenting a new field-level protocol for this work, we have decided to adopt the IO-Link specification which already includes a plug-and-play approach with features such as diagnosis and device configuration. The main objective of this work is to explore how field devices could be integrated into 10BASE-TIL Ethernet, its adaption with a well-known protocol, and its integration with Industry 4.0 technologies.}, language = {en} } @inproceedings{ChavezBermudezWollert2019, author = {Chavez Bermudez, Victor Francisco and Wollert, J{\"o}rg}, title = {Gateway for Automation Controllers and Cloud based Voice Recognition Services}, series = {KommA, 10. Jahreskolloquium Kommunikation in der Automation}, booktitle = {KommA, 10. Jahreskolloquium Kommunikation in der Automation}, publisher = {Institut f{\"u}r Automation und Kommunikation}, address = {Magdeburg}, organization = {KommA, 2019, Jahreskolloquium Kommunikation in der Automation, 10., Lemgo, DE, 2019-11-20 - 2019-11-21}, isbn = {978-3-944722-85-6}, pages = {1 -- 8}, year = {2019}, language = {en} } @inproceedings{ChavezBermudezWollert2020, author = {Chavez Bermudez, Victor Francisco and Wollert, J{\"o}rg}, title = {Arduino based Framework for Rapid Application Development of a Generic IO-Link interface}, series = {Kommunikation und Bildverarbeitung in der Automation}, booktitle = {Kommunikation und Bildverarbeitung in der Automation}, publisher = {Springer Vieweg}, address = {Berlin}, isbn = {978-3-662-59895-5}, doi = {10.1007/978-3-662-59895-5_2}, pages = {21 -- 33}, year = {2020}, abstract = {The implementation of IO-Link in the automation industry has increased over the years. Its main advantage is it offers a digital point-to-point plugand-play interface for any type of device or application. This simplifies the communication between devices and increases productivity with its different features like self-parametrization and maintenance. However, its complete potential is not always used. The aim of this paper is to create an Arduino based framework for the development of generic IO-Link devices and increase its implementation for rapid prototyping. By generating the IO device description file (IODD) from a graphical user interface, and further customizable options for the device application, the end-user can intuitively develop generic IO-Link devices. The peculiarity of this framework relies on its simplicity and abstraction which allows to implement any sensor functionality and virtually connect any type of device to an IO-Link master. This work consists of the general overview of the framework, the technical background of its development and a proof of concept which demonstrates the workflow for its implementation.}, language = {en} } @inproceedings{ChavezBermudezCruzCastanonRuchayetal.2022, author = {Chavez Bermudez, Victor Francisco and Cruz Castanon, Victor Fernando and Ruchay, Marco and Wollert, J{\"o}rg}, title = {Rapid prototyping framework for automation applications based on IO-Link}, series = {Tagungsband AALE 2022}, booktitle = {Tagungsband AALE 2022}, editor = {Leipzig, Hochschule f{\"u}r Technik, Wirtschaft und Kultur}, address = {Leipzig}, isbn = {978-3-910103-00-9}, doi = {10.33968/2022.28}, pages = {8 Seiten}, year = {2022}, abstract = {The development of protype applications with sensors and actuators in the automation industry requires tools that are independent of manufacturer, and are flexible enough to be modified or extended for any specific requirements. Currently, developing prototypes with industrial sensors and actuators is not straightforward. First of all, the exchange of information depends on the industrial protocol that these devices have. Second, a specific configuration and installation is done based on the hardware that is used, such as automation controllers or industrial gateways. This means that the development for a specific industrial protocol, highly depends on the hardware and the software that vendors provide. In this work we propose a rapid-prototyping framework based on Arduino to solve this problem. For this project we have focused to work with the IO-Link protocol. The framework consists of an Arduino shield that acts as the physical layer, and a software that implements the IO-Link Master protocol. The main advantage of such framework is that an application with industrial devices can be rapid-prototyped with ease as its vendor independent, open-source and can be ported easily to other Arduino compatible boards. In comparison, a typical approach requires proprietary hardware, is not easy to port to another system and is closed-source.}, language = {en} } @inproceedings{ChajanSchulteTiggesRekeetal.2021, author = {Chajan, Eduard and Schulte-Tigges, Joschua and Reke, Michael and Ferrein, Alexander and Matheis, Dominik and Walter, Thomas}, title = {GPU based model-predictive path control for self-driving vehicles}, series = {IEEE Intelligent Vehicles Symposium (IV)}, booktitle = {IEEE Intelligent Vehicles Symposium (IV)}, publisher = {IEEE}, isbn = {978-1-7281-5394-0}, doi = {10.1109/IV48863.2021.9575619}, pages = {1243 -- 1248}, year = {2021}, abstract = {One central challenge for self-driving cars is a proper path-planning. Once a trajectory has been found, the next challenge is to accurately and safely follow the precalculated path. The model-predictive controller (MPC) is a common approach for the lateral control of autonomous vehicles. The MPC uses a vehicle dynamics model to predict the future states of the vehicle for a given prediction horizon. However, in order to achieve real-time path control, the computational load is usually large, which leads to short prediction horizons. To deal with the computational load, the control algorithm can be parallelized on the graphics processing unit (GPU). In contrast to the widely used stochastic methods, in this paper we propose a deterministic approach based on grid search. Our approach focuses on systematically discovering the search area with different levels of granularity. To achieve this, we split the optimization algorithm into multiple iterations. The best sequence of each iteration is then used as an initial solution to the next iteration. The granularity increases, resulting in smooth and predictable steering angle sequences. We present a novel GPU-based algorithm and show its accuracy and realtime abilities with a number of real-world experiments.}, language = {en} } @inproceedings{CarzanaDachwaldNoomen2017, author = {Carzana, Livio and Dachwald, Bernd and Noomen, Ron}, title = {Model and trajectory optimization for an ideal laser-enhanced solar sail}, series = {68th International Astronautical Congress}, booktitle = {68th International Astronautical Congress}, year = {2017}, abstract = {A laser-enhanced solar sail is a solar sail that is not solely propelled by solar radiation but additionally by a laser beam that illuminates the sail. This way, the propulsive acceleration of the sail results from the combined action of the solar and the laser radiation pressure onto the sail. The potential source of the laser beam is a laser satellite that coverts solar power (in the inner solar system) or nuclear power (in the outer solar system) into laser power. Such a laser satellite (or many of them) can orbit anywhere in the solar system and its optimal orbit (or their optimal orbits) for a given mission is a subject for future research. This contribution provides the model for an ideal laser-enhanced solar sail and investigates how a laser can enhance the thrusting capability of such a sail. The term "ideal" means that the solar sail is assumed to be perfectly reflecting and that the laser beam is assumed to have a constant areal power density over the whole sail area. Since a laser beam has a limited divergence, it can provide radiation pressure at much larger solar distances and increase the radiation pressure force into the desired direction. Therefore, laser-enhanced solar sails may make missions feasible, that would otherwise have prohibitively long flight times, e.g. rendezvous missions in the outer solar system. This contribution will also analyze exemplary mission scenarios and present optimial trajectories without laying too much emphasis on the design and operations of the laser satellites. If the mission studies conclude that laser-enhanced solar sails would have advantages with respect to "traditional" solar sails, a detailed study of the laser satellites and the whole system architecture would be the second next step}, language = {en} }