TY - JOUR A1 - Cheenakula, Dheeraja A1 - Griebel, Kai A1 - Montag, David A1 - Grömping, Markus ED - Huang, Xiaowu T1 - Concept development of a mainstream deammonification and comparison with conventional process in terms of energy, performance and economical construction perspectives JF - Frontiers in Microbiology N2 - Deammonification for nitrogen removal in municipal wastewater in temperate and cold climate zones is currently limited to the side stream of municipal wastewater treatment plants (MWWTP). This study developed a conceptual model of a mainstream deammonification plant, designed for 30,000 P.E., considering possible solutions corresponding to the challenging mainstream conditions in Germany. In addition, the energy-saving potential, nitrogen elimination performance and construction-related costs of mainstream deammonification were compared to a conventional plant model, having a single-stage activated sludge process with upstream denitrification. The results revealed that an additional treatment step by combining chemical precipitation and ultra-fine screening is advantageous prior the mainstream deammonification. Hereby chemical oxygen demand (COD) can be reduced by 80% so that the COD:N ratio can be reduced from 12 to 2.5. Laboratory experiments testing mainstream conditions of temperature (8–20°C), pH (6–9) and COD:N ratio (1–6) showed an achievable volumetric nitrogen removal rate (VNRR) of at least 50 gN/(m3∙d) for various deammonifying sludges from side stream deammonification systems in the state of North Rhine-Westphalia, Germany, where m3 denotes reactor volume. Assuming a retained Norganic content of 0.0035 kgNorg./(P.E.∙d) from the daily loads of N at carbon removal stage and a VNRR of 50 gN/(m3∙d) under mainstream conditions, a resident-specific reactor volume of 0.115 m3/(P.E.) is required for mainstream deammonification. This is in the same order of magnitude as the conventional activated sludge process, i.e., 0.173 m3/(P.E.) for an MWWTP of size class of 4. The conventional plant model yielded a total specific electricity demand of 35 kWh/(P.E.∙a) for the operation of the whole MWWTP and an energy recovery potential of 15.8 kWh/(P.E.∙a) through anaerobic digestion. In contrast, the developed mainstream deammonification model plant would require only a 21.5 kWh/(P.E.∙a) energy demand and result in 24 kWh/(P.E.∙a) energy recovery potential, enabling the mainstream deammonification model plant to be self-sufficient. The retrofitting costs for the implementation of mainstream deammonification in existing conventional MWWTPs are nearly negligible as the existing units like activated sludge reactors, aerators and monitoring technology are reusable. However, the mainstream deammonification must meet the performance requirement of VNRR of about 50 gN/(m3∙d) in this case. KW - anammox KW - energy efficiency KW - mainstream deammonification KW - nitrogen elimination KW - wastewater Y1 - 2023 U6 - https://doi.org/10.3389/fmicb.2023.1155235 SN - 1664-302X VL - 14 IS - 11155235 SP - 1 EP - 15 PB - Frontiers ER - TY - JOUR A1 - Ringers, Christa A1 - Bialonski, Stephan A1 - Ege, Mert A1 - Solovev, Anton A1 - Hansen, Jan Niklas A1 - Jeong, Inyoung A1 - Friedrich, Benjamin M. A1 - Jurisch-Yaksi, Nathalie T1 - Novel analytical tools reveal that local synchronization of cilia coincides with tissue-scale metachronal waves in zebrafish multiciliated epithelia JF - eLife N2 - Motile cilia are hair-like cell extensions that beat periodically to generate fluid flow along various epithelial tissues within the body. In dense multiciliated carpets, cilia were shown to exhibit a remarkable coordination of their beat in the form of traveling metachronal waves, a phenomenon which supposedly enhances fluid transport. Yet, how cilia coordinate their regular beat in multiciliated epithelia to move fluids remains insufficiently understood, particularly due to lack of rigorous quantification. We combine experiments, novel analysis tools, and theory to address this knowledge gap. To investigate collective dynamics of cilia, we studied zebrafish multiciliated epithelia in the nose and the brain. We focused mainly on the zebrafish nose, due to its conserved properties with other ciliated tissues and its superior accessibility for non-invasive imaging. We revealed that cilia are synchronized only locally and that the size of local synchronization domains increases with the viscosity of the surrounding medium. Even though synchronization is local only, we observed global patterns of traveling metachronal waves across the zebrafish multiciliated epithelium. Intriguingly, these global wave direction patterns are conserved across individual fish, but different for left and right noses, unveiling a chiral asymmetry of metachronal coordination. To understand the implications of synchronization for fluid pumping, we used a computational model of a regular array of cilia. We found that local metachronal synchronization prevents steric collisions, i.e., cilia colliding with each other, and improves fluid pumping in dense cilia carpets, but hardly affects the direction of fluid flow. In conclusion, we show that local synchronization together with tissue-scale cilia alignment coincide and generate metachronal wave patterns in multiciliated epithelia, which enhance their physiological function of fluid pumping. Y1 - 2023 U6 - https://doi.org/10.7554/eLife.77701 SN - 2050-084X VL - 12 PB - eLife Sciences Publications ER - TY - CHAP A1 - Schwager, Christian A1 - Angele, Florian A1 - Schwarzbözl, Peter A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf T1 - Model predictive assistance for operational decision making in molten salt receiver systems T2 - SolarPACES: Solar Power & Chemical Energy Systems N2 - Despite the challenges of pioneering molten salt towers (MST), it remains the leading technology in central receiver power plants today, thanks to cost effective storage integration and high cost reduction potential. The limited controllability in volatile solar conditions can cause significant losses, which are difficult to estimate without comprehensive modeling [1]. This paper presents a Methodology to generate predictions of the dynamic behavior of the receiver system as part of an operating assistance system (OAS). Based on this, it delivers proposals if and when to drain and refill the receiver during a cloudy period in order maximize the net yield and quantifies the amount of net electricity gained by this. After prior analysis with a detailed dynamic two-phase model of the entire receiver system, two different reduced modeling approaches where developed and implemented in the OAS. A tailored decision algorithm utilizes both models to deliver the desired predictions efficiently and with appropriate accuracy. KW - Power plants KW - Associated liquids KW - Decision theory KW - Electrochemistry Y1 - 2023 SN - 978-0-7354-4623-6 U6 - https://doi.org/10.1063/5.0151514 SN - 1551-7616 (online) SN - 0094-243X (print) N1 - SolarPACES: SOLAR POWER & CHEMICAL ENERGY SYSTEMS: 27th International Conference on Concentrating Solar Power and Chemical Energy Systems, 27 September–1 October 2021, Online IS - 2815 / 1 PB - AIP conference proceedings / American Institute of Physics CY - Melville, NY ER - TY - JOUR A1 - Berg-Postweiler, Julia A1 - Steuer-Dankert, Linda A1 - Leicht-Scholten, Carmen T1 - One size does not fit all: Applying antibias trainings in academia JF - The International Journal of Organizational Diversity N2 - Antibias training is increasingly demanded and practiced in academia and industry to increase employees’ sensitivity to discrimination, racism, and diversity. Under the heading of “Diversity Management,” antibias trainings are mainly offered as one-off workshops intending to raise awareness of unconscious biases, create a diversity-affirming corporate culture, promote awareness of the potential of diversity, and ultimately enable the reflection of diversity in development processes. However, coming from childhood education, research and scientific articles on the sustainable effectiveness of antibias in adulthood, especially in academia, are very scarce. In order to fill this research gap, the article aims to explore how sustainable the effects of individual antibias trainings on participants’ behavior are. In order to investigate this, participant observation in a qualitative pre–post setting was conducted, analyzing antibias training in an academic context. Two observers actively participated in the training sessions and documented the activities and reflection processes of the participants. Overall, the results question the effectiveness of single antibias trainings and show that a target-group adaptive approach is mandatory owing to the background of the approach in early childhood education. Therefore, antibias work needs to be adapted to the target group’s needs and realities of life. Furthermore, the study reveals that single antibias trainings must be embedded in a holistic diversity management approach to stimulate sustainable reflection processes among the target group. This article is one of the first to scientifically evaluate antibias training effectiveness, especially in engineering sciences and the university context. KW - Antibias KW - Diversity Management KW - Organizational Culture KW - Engineering Habitus Y1 - 2023 U6 - https://doi.org/10.18848/2328-6261/CGP/v24i01/1-23 SN - 2328-6261 (Print) SN - 2328-6229 (Online) VL - 24 IS - 1 SP - 1 EP - 23 PB - Common Ground Research Networks ER - TY - CHAP A1 - Steuer-Dankert, Linda T1 - Training future skills - sustainability, interculturality & innovation in a digital design thinking format T2 - Proceedings of the 19th International CDIO Conference N2 - The complex questions of today for a world of tomorrow are characterized by their global impact. Solutions must therefore not only be sustainable in the sense of the three pillars of sustainability (economic, environmental, and social) but must also function globally. This goes hand in hand with the need for intercultural acceptance of developed services and products. To achieve this, engineers, as the problem solvers of the future, must be able to work in intercultural teams on appropriate solutions, and be sensitive to intercultural perspectives. To equip the engineers of the future with the so-called future skills, teaching concepts are needed in which students can acquire these methods and competencies in application-oriented formats. The presented course "Applying Design Thinking - Sustainability, Innovation and Interculturality" was developed to teach future skills from the competency areas Digital Key Competencies, Classical Competencies and Transformative Competencies. The CDIO Standard 3.0, in particular the standards 5, 6, 7 and 8, was used as a guideline. The course aims to prepare engineering students from different disciplines and cultures for their future work in an international environment by combining a digital teaching format with an interdisciplinary, transdisciplinary and intercultural setting for solving sustainability challenges. The innovative moment lies in the digital application of design thinking and the inclusion of intercultural as well as trans- and interdisciplinary perspectives in innovation development processes. In this paper, the concept of the course will be presented in detail and the particularities of a digital implementation of design thinking will be addressed. Subsequently, the potentials and challenges will be reflected and practical advice for integrating design thinking in engineering education will be given. KW - Design Thinking KW - Sustainability KW - Future Skills KW - Interculturality KW - Interdisciplinarity Y1 - 2023 N1 - 19th International CDIO Conference, hosted by NTNU, Trondheim, Norway, June 26-29, 2023 ER - TY - GEN A1 - Hille, Sebastian A1 - Stumpf, Eike A1 - Mayntz, Joscha A1 - Dahmann, Peter T1 - Prediction of sound exposure caused by a landing motor glider with recuperating propellers T2 - AIAA SCITECH 2023 Forum N2 - This paper presents an approach to predicting the sound exposure on the ground caused by a landing aircraft with recuperating propellers. The noise source along the trajectory of a flight specified for a steeper approach is simulated based on measurements of sound power levels and additional parameters of a single propeller placed in a wind tunnel. To validate the measured data/measurement results, these simulations are also supported by overflight measurements of a test aircraft. It is shown that the simple source models of propellers do not provide fully satisfactory results since the sound levels are estimated too low. Nevertheless, with a further reference comparison, margins for an acceptable increase in the sound power level of the aircraft on its now steeper approach path could be estimated. Thus, in this case, a +7 dB increase in SWL would not increase the SEL compared to the conventional approach within only 2 km ahead of the airfield. Y1 - 2023 U6 - https://doi.org/10.2514/6.2023-0211 N1 - AIAA SCITECH 2023 Forum, 23-27 January 2023, National Harbor, Md & Online PB - AIAA CY - Reston, Va. ER - TY - CHAP A1 - Lahrs, Lennart A1 - Krisam, Pierre A1 - Herrmann, Ulf T1 - Envisioning a collaborative energy system planning platform for the energy transition at the district level T2 - ECOS 2023. The 36th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems N2 - Residential and commercial buildings account for more than one-third of global energy-related greenhouse gas emissions. Integrated multi-energy systems at the district level are a promising way to reduce greenhouse gas emissions by exploiting economies of scale and synergies between energy sources. Planning district energy systems comes with many challenges in an ever-changing environment. Computational modelling established itself as the state-of-the-art method for district energy system planning. Unfortunately, it is still cumbersome to combine standalone models to generate insights that surpass their original purpose. Ideally, planning processes could be solved by using modular tools that easily incorporate the variety of competing and complementing computational models. Our contribution is a vision for a collaborative development and application platform for multi-energy system planning tools at the district level. We present challenges of district energy system planning identified in the literature and evaluate whether this platform can help to overcome these challenges. Further, we propose a toolkit that represents the core technical elements of the platform. Lastly, we discuss community management and its relevance for the success of projects with collaboration and knowledge sharing at their core. KW - Energy system planning KW - District energy planning platform KW - District data model KW - Renewable energy integration Y1 - 2023 U6 - https://doi.org/10.52202/069564-0284 N1 - ECOS 2023. The 36th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, 25-30 JUNE, 2023, Las Palmas de Gran Canaria, Spain SP - 3163 EP - 3170 PB - Procedings of ECOS 2023 ER - TY - JOUR A1 - Haeger, Gerrit A1 - Grankin, Alina A1 - Wagner, Michaela T1 - Construction of an Aspergillus oryzae triple amylase deletion mutant as a chassis to evaluate industrially relevant amylases using multiplex CRISPR/Cas9 editing technology JF - Applied Research N2 - Aspergillus oryzae is an industrially relevant organism for the secretory production of heterologous enzymes, especially amylases. The activities of potential heterologous amylases, however, cannot be quantified directly from the supernatant due to the high background activity of native α-amylase. This activity is caused by the gene products of amyA, amyB, and amyC. In this study, an in vitro CRISPR/Cas9 system was established in A. oryzae to delete these genes simultaneously. First, pyrG of A. oryzae NSAR1 was mutated by exploiting NHEJ to generate a counter-selection marker. Next, all amylase genes were deleted simultaneously by co-transforming a repair template carrying pyrG of Aspergillus nidulans and flanking sequences of amylase gene loci. The rate of obtained triple knock-outs was 47%. We showed that triple knockouts do not retain any amylase activity in the supernatant. The established in vitro CRISPR/Cas9 system was used to achieve sequence-specific knock-in of target genes. The system was intended to incorporate a single copy of the gene of interest into the desired host for the development of screening methods. Therefore, an integration cassette for the heterologous Fpi amylase was designed to specifically target the amyB locus. The site-specific integration rate of the plasmid was 78%, with exceptional additional integrations. Integration frequency was assessed via qPCR and directly correlated with heterologous amylase activity. Hence, we could compare the efficiency between two different signal peptides. In summary, we present a strategy to exploit CRISPR/Cas9 for gene mutation, multiplex knock-out, and the targeted knock-in of an expression cassette in A. oryzae. Our system provides straightforward strain engineering and paves the way for development of fungal screening systems. KW - aspergillus KW - CRISPR/Cas9 KW - filamentous fungi KW - genome engineering Y1 - 2023 U6 - https://doi.org/10.1002/appl.202200106 SN - 2702-4288 IS - Early View SP - 1 EP - 15 PB - Wiley-VCH ER - TY - JOUR A1 - Pfaff, Raphael T1 - Braking distance prediction for vehicle consist in low-speed on-sight operation: a Monte Carlo approach JF - Railway Engineering Science N2 - The first and last mile of a railway journey, in both freight and transit applications, constitutes a high effort and is either non-productive (e.g. in the case of depot operations) or highly inefficient (e.g. in industrial railways). These parts are typically managed on-sight, i.e. with no signalling and train protection systems ensuring the freedom of movement. This is possible due to the rather short braking distances of individual vehicles and shunting consists. The present article analyses the braking behaviour of such shunting units. For this purpose, a dedicated model is developed. It is calibrated on published results of brake tests and validated against a high-definition model for low-speed applications. Based on this model, multiple simulations are executed to obtain a Monte Carlo simulation of the resulting braking distances. Based on the distribution properties and established safety levels, the risk of exceeding certain braking distances is evaluated and maximum braking distances are derived. Together with certain parameters of the system, these can serve in the design and safety assessment of driver assistance systems and automation of these processes. KW - Freight rail KW - Shunting KW - Braking curves KW - Brake set-up KW - Driver assistance system Y1 - 2023 U6 - https://doi.org/10.1007/s40534-023-00303-7 SN - 2662-4753 (eISSN) SN - 2662-4745 (Print) VL - 31 IS - 2 SP - 135 EP - 144 PB - SpringerOpen ER - TY - CHAP A1 - Nierle, Elisabeth A1 - Pieper, Martin T1 - Measuring social impacts in engineering education to improve sustainability skills T2 - European Society for Engineering Education (SEFI) N2 - In times of social climate protection movements, such as Fridays for Future, the priorities of society, industry and higher education are currently changing. The consideration of sustainability challenges is increasing. In the context of sustainable development, social skills are crucial to achieving the United Nations Sustainable Development Goals (SDGs). In particular, the impact that educational activities have on people, communities and society is therefore coming to the fore. Research has shown that people with high levels of social competence are better able to manage stressful situations, maintain positive relationships and communicate effectively. They are also associated with better academic performance and career success. However, especially in engineering programs, the social pillar is underrepresented compared to the environmental and economic pillars. In response to these changes, higher education institutions should be more aware of their social impact - from individual forms of teaching to entire modules and degree programs. To specifically determine the potential for improvement and derive resulting change for further development, we present an initial framework for social impact measurement by transferring already established approaches from the business sector to the education sector. To demonstrate the applicability, we measure the key competencies taught in undergraduate engineering programs in Germany. The aim is to prepare the students for success in the modern world of work and their future contribution to sustainable development. Additionally, the university can include the results in its sustainability report. Our method can be applied to different teaching methods and enables their comparison. KW - Social impact measurement KW - Key competences KW - Sustainable engineering education KW - Future skills Y1 - 2023 U6 - https://doi.org/10.21427/QPR4-0T22 N1 - 51st Annual Conference of the European Society for Engineering Education, Technological University Dublin, 10th-14th September, 2023 N1 - Corresponding Author: Elisabeth Nierle ER -