@inproceedings{Mertens2017, author = {Mertens, K.}, title = {„Status der Photovoltaik", Tagung „Solarstrahlung - Wirkung, Anwendung, Messung und Simulation", Deutsche Akademie f{\"u}r Photobiologie und Phototechnologie e.V., Freiburg, 19.05.2017}, year = {2017}, language = {de} } @inproceedings{MertensArndsDiehl2017, author = {Mertens, K. and Arnds, A. and Diehl, M.}, title = {"Quick and Effective Plant Evaluation Using Dark-IV String Curves"}, series = {Proceedings of 33st European Photovoltaic Solar Energy Conference, Amsterdam, 2017}, booktitle = {Proceedings of 33st European Photovoltaic Solar Energy Conference, Amsterdam, 2017}, address = {Amsterdam}, isbn = {3-936338-47-7}, doi = {10.4229/EUPVSEC201}, pages = {2346 -- 2348}, year = {2017}, language = {en} } @inproceedings{Mertens2018, author = {Mertens, K.}, title = {"Do Photovoltaics make sense in countries like Germany?", Invited Paper zur 7th International Energy and Sustainability Confrerence, Cologne Institute for Renewable Energy CIRE der TH K{\"o}ln, 17.05.2018, K{\"o}ln}, year = {2018}, language = {en} } @inproceedings{Mertens2018, author = {Mertens, Konrad}, title = {„String-Dunkelkennlinien: Eine neue effiziente Methode zur Anlagenevaluation", 33. Symposium Photovoltaische Solarenergie, Staffelstein, 27.04.2018}, year = {2018}, language = {de} } @inproceedings{Mertens2018, author = {Mertens, K.}, title = {„String-Dunkelkennlinien-Technik zur Diagnose von PV-Anlagen", Solarkampagne des Kreises Steinfurt, Betriebs- und Sicherheitstagung der DGS, Berlin, 17.10.2018}, year = {2018}, language = {de} } @inproceedings{LoechteGebertHorsthemkeetal.2018, author = {L{\"o}chte, Andre and Gebert, Ole and Horsthemke, Ludwig and Heming, Daniel and Gl{\"o}sek{\"o}tter, Peter}, title = {State of Charge Depended Modeling of an Equivalent Circuit of Zinc Air Batteries Using Electrochemical Impedance Spectroscopy}, series = {International Conference on Time Series and Forecasting: Proceedings of Papers, 19-21 September 2018, Granada (Spain)}, booktitle = {International Conference on Time Series and Forecasting: Proceedings of Papers, 19-21 September 2018, Granada (Spain)}, isbn = {978-84-17293-57-4}, pages = {625 -- 636}, year = {2018}, abstract = {Metal air batteries provide a high energy density as the ca-thodic reaction uses the surrounding air. Different metals can be usedbut zinc is very promising due to its disposability and nontoxic behav-ior. State estimation is quite complicated as the voltage characteristicof the battery is rather flat. Especially estimating the state of chargeis important as a secondary electrolysis process during overcharging canlead to an unsafe state. Another technique for state estimation is theelectrochemical impedance spectroscopy. Therefore, this paper describesthe process of setup and measuring a time series of impedance spectraat known states of charge. Then these spectra are used to derive anequivalent circuit. Finally the development of the circuit's parameter areanalyzed to extract most important parameters.}, language = {de} } @inproceedings{LoechteGebertHemingetal.2018, author = {L{\"o}chte, Andre and Gebert, Ole and Heming, Daniel and Kallis, Klaus and Gl{\"o}sek{\"o}tter, Peter}, title = {State estimation of zinc air batteries using neural networks}, series = {IWANN 2017: Advances in Computational Intelligence}, volume = {2018}, booktitle = {IWANN 2017: Advances in Computational Intelligence}, editor = {Springer, Axel}, issn = {0941-0643}, doi = {10.1007/s00521-018-3705-9}, pages = {1 -- 9}, year = {2018}, abstract = {The main task of battery management systems is to keep the working area of the battery in a safe state. Estimation of the state of charge and the state of health is therefore essential. The traditional way uses the voltage level of a battery to determine those values. Modern metal air batteries provide a flat voltage characteristic which necessitates new approaches. One promising technique is the electrochemical impedance spectroscopy, which measures the AC resistance for a set of different frequencies. Previous approaches match the measured impedances with a nonlinear equivalent circuit, which needs a lot of time to solve a nonlinear least-squares problem. This paper combines the electrochemical impedance spectroscopy with neural networks to speed up the state estimation using the example of zinc air batteries. Moreover, these networks are trained with different subsets of the spectra as input data in order to determine the required number of frequencies.}, language = {de} } @inproceedings{MuellerBrinkmannPoddebniaketal.2019, author = {M{\"u}ller, Jens and Brinkmann, Marcus and Poddebniak, Damian and B{\"o}ck, Hanno and Schinzel, Sebastian and Smomrosvsky, Juraj and Schwenk, J{\"o}rg}, title = {"Johnny, you are fired!" - Spoofing OpenPGP and S/MIME Signatures in Emails}, series = {28th Usenix Security Symposium, Santa Clara, CA, USA}, booktitle = {28th Usenix Security Symposium, Santa Clara, CA, USA}, year = {2019}, abstract = {OpenPGP and S/MIME are the two major standards to en-crypt and digitally sign emails. Digital signatures are sup-posed to guarantee authenticity and integrity of messages. Inthis work we show practical forgery attacks against variousimplementations of OpenPGP and S/MIME email signatureverification in five attack classes: (1) We analyze edge casesin S/MIME's container format. (2) We exploit in-band sig-naling in the GnuPG API, the most widely used OpenPGPimplementation. (3) We apply MIME wrapping attacks thatabuse the email clients' handling of partially signed mes-sages. (4) We analyze weaknesses in the binding of signedmessages to the sender identity. (5) We systematically testemail clients for UI redressing attacks.Our attacks allow the spoofing of digital signatures for ar-bitrary messages in 14 out of 20 tested OpenPGP-capableemail clients and 15 out of 22 email clients supportingS/MIME signatures. While the attacks do not target the un-derlying cryptographic primitives of digital signatures, theyraise concerns about the actual security of OpenPGP andS/MIME email applications. Finally, we propose mitigationstrategies to counter these attacks.}, language = {de} } @inproceedings{MuellerBrinkmannPoddebniaketal.2019, author = {M{\"u}ller, Jens and Brinkmann, Marcus and Poddebniak, Damian and Schinzel, Sebastian and Schwenk, J{\"o}rg}, title = {What's up John­ny? - Co­vert Con­tent At­tacks on Email End-to-End En­cryp­ti­on}, series = {17th In­ter­na­tio­nal Con­fe­rence on Ap­p­lied Cryp­to­gra­phy and Net­work Se­cu­ri­ty (ACNS 2019)}, booktitle = {17th In­ter­na­tio­nal Con­fe­rence on Ap­p­lied Cryp­to­gra­phy and Net­work Se­cu­ri­ty (ACNS 2019)}, pages = {1 -- 18}, year = {2019}, abstract = {We show practical attacks against OpenPGP and S/MIMEencryption and digital signatures in the context of email. Instead of tar-geting the underlying cryptographic primitives, our attacks abuse legiti-mate features of the MIME standard and HTML, as supported by emailclients, to deceive the user regarding the actual message content. Wedemonstrate how the attacker can unknowingly abuse the user as a de-cryption oracle by replying to an unsuspicious looking email. Using thistechnique, the plaintext of hundreds of encrypted emails can be leakedat once. Furthermore, we show how users could be tricked into signingarbitrary text by replying to emails containing CSS conditional rules.An evaluation shows that "out of" OpenPGP-capable email clients,as well as "out of" clients supporting S/MIME, are vulnerable to atleast one attack. We provide different countermeasures and discuss theiradvantages and disadvantages.}, language = {de} } @inproceedings{WeβelerKaiserteVrugtetal.2018, author = {Weβeler, Peter and Kaiser, Benjamin and te Vrugt, J{\"u}rgen and Lechler, Armin and Verl, Alexander}, title = {Camera based path planning for low quantity - high variant manufacturing with industrial robots}, series = {25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP)}, booktitle = {25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP)}, publisher = {IEEE}, isbn = {978-1-5386-7544-1}, doi = {10.1109/M2VIP.2018.8600833}, pages = {1 -- 6}, year = {2018}, abstract = {The acquisition costs for industrial robots have been steadily decreasing in past years. Nevertheless, they still face significant drawbacks in the required effort for the preparation of complex robot tasks which causes these systems to be rarely present so far in small and medium-sized enterprises (SME) that focus mainly on small volume, high variant manufacturing. In this paper, we propose a camera-based path planning framework that allows the fast preparation and execution of robot tasks in dynamic environments which leads to less planning overhead, fast program generation and reduced cost and hence overcomes the major impediments for the usage of industrial robots for automation in SMEs with focus on low volume and high variant manufacturing. The framework resolves existing problems in different steps. The exact position and orientation of the workpiece are determined from a 3D environment model scanned by an optical sensor. The so retrieved information is used to plan a collision-free path that meets the boundary conditions of the specific robot task. Experiments show the potential and effectiveness of the the framework presented here by evaluating a case study.}, language = {en} }