TY - JOUR A1 - Mathias, Selvine George A1 - Schmied, Sebastian A1 - Großmann, Daniel T1 - A framework for monitoring multiple databases in industries using OPC UA JF - Journal of Ambient Intelligence and Humanized Computing N2 - Database management and monitoring is an inseparable part of any industry. A uniform scheme of monitoring relational databases without explicit user access to database servers is not much explored outside the database environment. In this paper, we present an information distribution scheme related to databases using Open Platform Communication Unified Architecture (OPC UA) servers to clients when multiple databases are involved in a factory. The aim is for external, but relevant clients, to be able to monitor this information mesh independent of explicit access to user schemas. A methodology to dispense data from, as well as check changes in databases using SQL queries and events is outlined and implemented using OPC UA servers. The structure can be used as a remote viewing application for multiple databases in one address space of an OPC UA server. UR - https://doi.org/10.1007/s12652-020-02850-x KW - OPC UA KW - Relational databases KW - Servers KW - Clients KW - Monitoring KW - Aggregation KW - SQL Y1 - 2020 UR - https://doi.org/10.1007/s12652-020-02850-x UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9464 SN - 1868-5145 VL - 12 IS - 1 SP - 47 EP - 56 PB - Springer CY - Berlin ER - TY - JOUR A1 - Lenk, Kerstin A1 - Gleirscher, Mario A1 - Nestler, Simon A1 - Rödiger, Stefan A1 - Petersen, Tom A1 - Loebel, Jens-Martin T1 - Lage und Zukunft des wissenschaftlichen Nachwuchses BT - eine Stellungnahme des Beirats des Wissenschaftlichen Nachwuchses (WiN) der Gesellschaft für Informatik (GI e.V.) JF - Informatik Spektrum N2 - Der Beirat des Wissenschaftlichen Nachwuchses (GI-WiN) der Gesellschaft für Informatik (GI) fordert und empfiehlt Maßnahmen zur Verbesserung der Lage von Promovierenden sowie Postdoktoranden und Postdoktorandinnen in der Informatik und anderen Technikwissenschaften. Promovierende sowie Postdoktoranden und Postdoktorandinnen im Bereich der Informatik sind in zunehmendem Maß von den komplexen strukturellen und finanziellen Problematiken des Wissenschafts- und Lehrbetriebs betroffen. Der Flaschenhals auf dem Weg zur Professur führt in der akademischen Karriere zu prekären Beschäftigungsverhältnissen. Die schwierige Vereinbarkeit von Familie und akademischer Karriere erzeugt eine zusätzliche Benachteiligung, insbesondere von Wissenschaftlerinnen. Mangelnde Qualitätssicherung sowie fehlende zuverlässige und vertrauenswürdige Prozesse erschweren die Aufdeckung und Aufarbeitung von Konflikten während der Promotionsphase und der Zeit des Postdoktorats. Fehlanreize im akademischen System beeinträchtigen eine direkte, intensive und regelmäßige Betreuung der jungen Akademiker durch Professorinnen und Professoren. Eine zeitnahe Bewältigung der in diesem Beitrag skizzierten Herausforderungen ist für den zukünftigen Fortbestand von Forschungseinrichtungen an Hochschulen sowie für eine erfolgreiche Fortführung des Prinzips der Bestenauslese von zentraler Bedeutung. Vor dem Hintergrund von bereits geplanten und durchgeführten Maßnahmen zur Stärkung des wissenschaftlichen Nachwuchses skizziert dieser Beitrag konkrete Maßnahmen; einerseits zur Verbesserung der Betreuung während der Promotionsphase und andererseits zur Strukturierung und Schaffung weiterer Karrierewege. N2 - The Advisory Board for Junior Scientific Staff (WiN) of the German Informatics Society (GI) calls for and recommends measures to improve the situation of doctoral candidates and post-doctoral researchers in computer science and other technical sciences. Doctoral and postdoctoral scientists in the field of computer science are increasingly affected by the complex structural and financial problems of academia. The bottleneck on the way to a professorship leads to precarious employment conditions in academic careers. The difficulty in combining family and academic careers creates an additional disadvantage, especially for female scientists. A lack of quality assurance and reliable and transparent decision-making processes make it difficult to identify and deal with conflicts during the doctoral and postdoctoral period. Misguided incentives in the academic system impair the direct, intensive and regular supervision of early career researchers. Timely coping with the challenges outlined in this paper is of central importance for the future survival of university research institutions and for a successful continuation of the principle of best selection. In addition to measures already planned and implemented to empower early career researchers, this paper outlines concrete measures to improve supervision during the doctoral phase, and to structure and create further career paths in academia. UR - https://doi.org/10.1007/s00287-020-01250-x Y1 - 2020 UR - https://doi.org/10.1007/s00287-020-01250-x UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9446 SN - 1432-122X VL - 43 IS - 2 SP - 94 EP - 102 PB - Springer CY - Berlin ER - TY - JOUR A1 - Liu, E A1 - Conti, Fosca A1 - Bhogaraju, Sri Krishna A1 - Signorini, Raffaella A1 - Pedron, Danilo A1 - Wunderle, Bernhard A1 - Elger, Gordon T1 - Thermomechanical stress in GaN-LEDs soldered onto Cu substrates studied using finite element method and Raman spectroscopy JF - Journal of Raman Spectroscopy N2 - Local thermomechanical stress can cause failures in semiconductor packages during long-time operation under harsh environmental conditions. This study helps to explain the packaging-induced stress in blue GaN-LEDs soldered onto copper substrates using AuSn alloy as lead-free interconnect material. Based on the finite element method, a virtual prototype is developed to simulate the thermomechanical behavior and stress in the LED and in the complete LED/AuSn/Cu assembly considering plastic and viscoplastic strain. The investigations were performed by varying the temperature between −50°C and 180°C. To validate the model, the simulation results are compared to experimental data collected with Raman spectroscopy. Studies of the urn:x-wiley:03770486:media:jrs5947:jrs5947-math-0003 phonon mode of GaN semiconductor are elaborated to understand the induced thermomechanical stress. The model enables evaluation of the stress in the interfaces of the assembly, which otherwise cannot be accessed by measurements. It serves to predict how assemblies would perform, before committing resources to build a physical prototype. UR - https://doi.org/10.1002/jrs.5947 KW - finite element method KW - gallium nitride (GaN) KW - LED KW - semiconductor KW - thermomechanical stress Y1 - 2020 UR - https://doi.org/10.1002/jrs.5947 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9438 SN - 1097-4555 VL - 51 IS - 10 SP - 2083 EP - 2094 PB - Wiley CY - Chichester ER - TY - JOUR A1 - Borgmann, Stefan A1 - Rieß, Beate A1 - Meintrup, David A1 - Klare, Ingo A1 - Werner, Guido T1 - Long-Lasting Decrease of the Acquisition of Enterococcus faecium and Gram-Negative Bacteria Producing Extended Spectrum Beta-Lactamase (ESBL) by Transient Application of Probiotics JF - International Journal of Environmental Research and Public Health (IJERPH) N2 - Previously it was shown that application of probiotics stopped the acquisition of vancomycin-resistant Enterococcus faecium (VRE) by patients in an early rehabilitation ward. Once the application of probiotics ended, we examined whether acquisition of VRE reoccurred. Furthermore, we examined whether probiotics altered prevalence of vancomycin-susceptible E. faecium (VSE) and Gram-negative bacteria, which produce extended spectrum beta-lactamase (ESBL). Although probiotic application ceased in April 2018, VRE-colonized patients rarely presented on that ward until 2019. Probiotic treatment also resulted in a decreased number of patients with VSE and ESBL. While decreased incidence of VRE occurred immediately, decreased VSE and ESBL numbers occurred months later. A probiotic-mediated decrease of VSE and ESBL incidence cannot be explained when assuming bacterial transmission exclusively as a linear cause and effect event. The decrease is better understood by considering bacterial transmissions to be stochastic events, which depend on various driving forces similar to an electric current. We hypothesize that VRE, VSE and ESBL uptake by patients and by staff members mutually reinforced each other, leading staff members to form a bacterial reservoir, similar to a condenser that stores electrical energy. Probiotic treatment then inhibited regeneration of that store, resulting in a breakdown of the driving force. UR - https://doi.org/10.3390/ijerph17176100 KW - colonic bacteria KW - Enterococcus faecium KW - vancomycin-resistant Enterococcus faecium KW - vancomycin-susceptible E. faecium KW - Staphylococcus aureus KW - beta-lactamase KW - probiotics KW - health care co-workers KW - electric current KW - transistor KW - condenser KW - electrical current hypothesis of bacterial transmission Y1 - 2020 UR - https://doi.org/10.3390/ijerph17176100 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9425 SN - 1660-4601 VL - 17 IS - 17 PB - MDPI CY - Basel ER - TY - JOUR A1 - Cazares, Adrián A1 - García-Contreras, Rodolfo A1 - Pérez-Velázquez, Judith T1 - Eco-evolutionary effects of bacterial cooperation on phage therapy BT - an unknown risk? JF - Frontiers in Microbiology N2 - If there is something we have learned from the antibiotic era, it is that indiscriminate use of a therapeutic agent without a clear understanding of its long-term evolutionary impact can have enormous health repercussions. This knowledge is particularly relevant when the therapeutic agents are remarkably adaptable and diverse biological entities capable of a plethora of interactions, most of which remain largely unexplored. Although phage therapy (PT) undoubtedly holds the potential to save lives, its current efficacy in case studies recalls the golden era of antibiotics, when these compounds were highly effective and the possibility of them becoming ineffective seemed remote. Safe PT schemes depend on our understanding of how phages interact with, and evolve in, highly complex environments. Here, we summarize and review emerging evidence in a commonly overlooked theme in PT: bacteria-phage interactions. In particular, we discuss the influence of quorum sensing (QS) on phage susceptibility, the consequent role of phages in modulating bacterial cooperation, and the potential implications of this relationship in PT, including how we can use this knowledge to inform PT strategies. We highlight that the influence of QS on phage susceptibility seems to be widespread but can have contrasting outcomes depending on the bacterial host, underscoring the need to thoroughly characterize this link in various bacterial models. Furthermore, we encourage researchers to exploit competition experiments, experimental evolution, and mathematical modeling to explore this relationship further in relevant infection models. Finally, we emphasize that long-term PT success requires research on phage ecology and evolution to inform the design of optimal therapeutic schemes. UR - https://doi.org/10.3389/fmicb.2020.590294 KW - phages KW - phage therapy KW - quorum sensing KW - bacteria-phage interactions KW - cheaters KW - anti-phage defense Y1 - 2020 UR - https://doi.org/10.3389/fmicb.2020.590294 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9408 SN - 1664-302X VL - 11 PB - Frontiers Media CY - Lausanne ER - TY - JOUR A1 - Hechelmann, Ron-Hendrik A1 - Seevers, Jan-Peter A1 - Otte, Alexander A1 - Sponer, Jan A1 - Stark, Matthias T1 - Renewable Energy Integration for Steam Supply of Industrial Processes: A Food Processing Case Study JF - Energies N2 - This study highlights the CO2,e -emission reduction potentials and related economic consequences for changing steam generation from fossil to renewable. Seven different utility concepts are developed, including a steam accumulator for load management. Peculiarities for the integration of biogas boilers, biomass-fuelled boilers, electrode steam boilers, biomethane-fuelled solid oxide fuel cells, micro gas turbine, solar energy systems, heat pumps and steam accumulators into a steam system with fluctuating steam demand are explained and the energy balance based models for the simulation study are described. The characteristics of batch processes, start up times and part load efficiency are considered via an annual dynamic simulation. Based on a detailed process analysis and dimensioning of the utilities and the accumulator a comprehensive simulation study is conducted for a pet food processing company having an average steam demand of 18,000 MWh at around 9 bar and 3 t/h. The results show that the highest CO2,e -emissions reduction of up to 63% is achieved by the transition to a solid biomass-fuelled boiler system. This leads to an increase of the operating costs by 27.8% UR - https://doi.org/10.3390/en13102532 KW - biomass boilers KW - fuel cell KW - solar thermal KW - electrode boiler KW - steam systems KW - food processing industry KW - decarbonisation KW - energy costs Y1 - 2020 UR - https://doi.org/10.3390/en13102532 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9397 SN - 1996-1073 VL - 13 IS - 10 PB - MDPI CY - Basel ER - TY - JOUR A1 - Bär, Katharina A1 - Wageneder, Stefanie A1 - Solka, Felix A1 - Saidi, Abdessamad A1 - Zörner, Wilfried T1 - Flexibility Potential of Photovoltaic Power Plant and Biogas Plant Hybrid Systems in the Distribution Grid JF - Chemical Engineering & Technology N2 - The potential of combining biogas and photovoltaic (PV) power plants in hybrid systems in the German distribution grid is analyzed. The focus of the present research is on balancing the intermittent power supply from PV power plants with the controllable power production of combined heat and power (CHP) units of biogas plants within a period of seconds. To achieve an increase of the total energy feed-in of biogas and PV power plants to the electricity grid, a biogas plant energy management system is described. System parameters, such as the variable feed-in of PV power plants or power ramps of the start-up process of controllable biogas plant CHP unit, are described and adapted to the global installed capacity of PV power plant and biogas plants in the German distribution grid. UR - https://doi.org/10.1002/ceat.202000025 KW - Biogas KW - Combined heat and power units KW - Distribution grid KW - Flexible electricity production KW - Photovoltaic power plants Y1 - 2020 UR - https://doi.org/10.1002/ceat.202000025 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9380 SN - 1521-4125 VL - 43 IS - 8 SP - 1571 EP - 1577 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Conti, Fosca A1 - Saidi, Abdessamad A1 - Goldbrunner, Markus T1 - Numeric Simulation-Based Analysis of the Mixing Process in Anaerobic Digesters of Biogas Plants JF - Chemical Engineering & Technology N2 - Stirring systems with two rotational three-bladed propellers were analyzed using computational fluid dynamics. The propellers are located at three heights and seven angles in a tank with 9 m radius. The fluid was characterized by non-Newtonian rheology and simulated by applying the k-ε turbulence model and the standard k-ω model. Reynolds numbers were estimated. High fluid speeds were obtained with the propellers located at a height of 2 m and oriented at 90° with respect to the tank radius. In the top regions of the tank, the fluid velocity was generally less intense and less affected by the angle setting. The configurations identified as good mixing systems showed power consumptions broadly distributed around 30 kW. UR - https://doi.org/10.1002/ceat.201900650 KW - Anaerobic digester KW - Biogas plant KW - Biomass KW - Fluid dynamics KW - Mixing Y1 - 2020 UR - https://doi.org/10.1002/ceat.201900650 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9379 SN - 1521-4125 VL - 43 IS - 8 SP - 1522 EP - 1529 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Frison, Anna-Katharina A1 - Forster, Yannick A1 - Wintersberger, Philipp A1 - Geisel, Viktoria A1 - Riener, Andreas T1 - Where We Come from and Where We Are Going: A Systematic Review of Human Factors Research in Driving Automation JF - Applied Sciences N2 - During the last decade, research has brought forth a large amount of studies that investigated driving automation from a human factor perspective. Due to the multitude of possibilities for the study design with regard to the investigated constructs, data collection methods, and evaluated parameters, at present, the pool of findings is heterogeneous and nontransparent. This literature review applied a structured approach, where five reviewers investigated n = 161 scientific papers of relevant journals and conferences focusing on driving automation between 2010 and 2018. The aim was to present an overview of the status quo of existing methodological approaches and investigated constructs to help scientists in conducting research with established methods and advanced study setups. Results show that most studies focused on safety aspects, followed by trust and acceptance, which were mainly collected through self-report measures. Driving/Take-Over performance also marked a significant portion of the published papers; however, a wide range of different parameters were investigated by researchers. Based on our insights, we propose a set of recommendations for future studies. Amongst others, this includes validation of existing results on real roads, studying long-term effects on trust and acceptance (and of course other constructs), or triangulation of self-reported and behavioral data. We furthermore emphasize the need to establish a standardized set of parameters for recurring use cases to increase comparability. To assure a holistic contemplation of automated driving, we moreover encourage researchers to investigate other constructs that go beyond safety. UR - https://doi.org/10.3390/app10248914 KW - automated driving KW - literature review KW - human–automation interaction KW - method development Y1 - 2020 UR - https://doi.org/10.3390/app10248914 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9369 SN - 2076-3417 VL - 10 IS - 24 PB - MDPI CY - Basel ER - TY - JOUR A1 - Bano, Tayyaba A1 - Hegner, Franziska A1 - Heinrich, Martin A1 - Schwarze, Rüdiger T1 - Investigation of Fluid-Structure Interaction Induced Bending for Elastic Flaps in a Cross Flow JF - Applied Sciences N2 - With the recent increase in the design of light and flexible structures, numerical investigations of fluid and structure together play a significant role in most engineering applications. Therefore, the current study presents an examination of fluid-structure interaction involving flexible structures. The problem is numerically solved by a commercial software ANSYS-Workbench. Two-way coupled three-dimensional transient simulations are carried out for the flexible flaps of different thicknesses in glycerin for a laminar flow and Reynolds number ranging from 3 < Re < 12. The bending line of the flaps is compared with experimental data for different alignments of the flaps relative to the fluid flow. The study reports the computation of the maximum tip-deflection and deformation of flaps fixed at the bottom and mounted normal to the flow. Additionally, drag coefficients for flexible flaps are computed and flow regimes in the wake of the flaps are presented. As well, the study gives an understanding on how the fluid response changes as the structure deforms and the model is appropriate to predict the behavior of thick and comparatively thinner flaps. The results are sufficiently encouraging to consider the present model for analyzing turbulent flow processes against flexible objects. UR - https://doi.org/10.3390/app10186177 KW - fluid-structure interaction KW - flexible flaps KW - bending line KW - deformation Y1 - 2020 UR - https://doi.org/10.3390/app10186177 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9299 SN - 2076-3417 VL - 10 IS - 18 PB - MDPI CY - Basel ER - TY - JOUR A1 - Conti, Fosca A1 - Saidi, Abdessamad A1 - Goldbrunner, Markus T1 - Evaluation Criteria and Benefit Analysis of Mixing Process in Anaerobic Digesters of Biogas Plants JF - Environmental and Climate Technologies N2 - A valid method to evaluate decisions of a project proposal is the so-called cost-benefit analysis. Criteria are selected and properly weighted to determine if the project is effective and feasible. The present research study is focused on methodical selection of design parameters to install two propeller mixers inside anaerobic digesters of biogas plants. A cylindrical tank of 1400 m3 was considered. For the model-based optimisation, the substrate was considered as a non-Newtonian fluid with a density of 1090 kg/m3. The Oswald-de Waele power-law model was selected to account for the rheological behaviour of the fluid. Installation parameters of the mixers were rotational angles and heights of the shafts of the two propellers. A computational model was developed to simulate the fluid dynamics depending on the mixing process inside the tank. Several configurations were analysed according to evaluating criteria such as the value of the fluid velocity, its distribution along the three spatial dimensions, and the power consumption to rotate the mixers. The maximum fluid velocity and minimum power consumption were observed when the propellers are located at intermediate height inside the tank and with the shafts perpendicular to the tank radius. With this configuration, the fluid reaches a maximum velocity of 0.28 m/s. According to the investigation, it is evident that mixing systems with propeller shafts deep-seated and parallel to the tank radius should be avoided, both in term of efficiency of the fluid mixing distribution and in term of power consumption. UR - https://doi.org/10.2478/rtuect-2020-0105 KW - Anaerobic digester KW - biomass KW - computational fluid dynamics (CFD) KW - Cost-Benefit Analysis (CBA) KW - evaluation criteria KW - flow velocity KW - full scale biogas digester KW - mixing KW - propeller Y1 - 2020 UR - https://doi.org/10.2478/rtuect-2020-0105 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9274 SN - 2255-8837 VL - 24 IS - 3 SP - 305 EP - 317 PB - De Gruyter Poland CY - Warsaw ER -