TY - JOUR A1 - Lahmer, Tom T1 - FEM-Based determination of real and complex elastic, dielectric, and piezoelectric moduli in piezoceramic materials JF - IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control N2 - We propose an enhanced iterative scheme for the precise reconstruction of piezoelectric material parameters from electric impedance and mechanical displacement measurements. It is based on finite-element simulations of the full three-dimensional piezoelectric equations, combined with an inexact Newton or nonlinear Landweber iterative inversion scheme. We apply our method to two piezoelectric materials and test its performance. For the first material, the manufacturer provides a full data set; for the second one, no material data set is available. For both cases, our inverse scheme, using electric impedance measurements as input data, performs well. KW - Finite-Elemente-Methode KW - Piezoelectric materials KW - Dielectric materials KW - Computational modeling KW - Frequency KW - Finite element methods KW - Manufacturing KW - Impedance measurement KW - Partial differential equations KW - Resonance KW - Resonanz Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20171030-36083 ER - TY - THES A1 - Stäudel, Jürgen T1 - Development, Implementation and Operation of Integrated Sanitation Systems Based on Material-Flows – Integrated Sanitation in the City of Darkhan, Mongolia - A Practicable Example N2 - The world society faces a huge challenge to implement the human right of “access to sanitation”. More and more it is accepted that the conventional approach towards providing sanitation services is not suitable to solve this problem. This dissertation examines the possibility to enhance “access to sanitation” for people who are living in areas with underdeveloped water and wastewater infrastructure systems. The idea hereby is to follow an integrated approach for sanitation, which allows for a mutual completion of existing infrastructure with resource-based sanitation systems. The notion “integrated sanitation system (iSaS)” is defined in this work and guiding principles for iSaS are formulated. Further on the implementation of iSaS is assessed at the example of a case study in the city of Darkhan in Mongolia. More than half of Mongolia’s population live in settlements where yurts (tents of Nomadic people) are predominant. In these settlements (or “ger areas”) sanitation systems are not existent and the hygienic situation is precarious. An iSaS has been developed for the ger areas in Darkhan and tested over more than two years. Further on a software-based model has been developed with the goal to describe and assess different variations of the iSaS. The results of the assessment of material-flows, monetary-flows and communication-flows within the iSaS are presented in this dissertation. The iSaS model is adaptable and transferable to the socio-economic conditions in other regions and climate zones. N2 - Die Weltgesellschaft steht der großen Herausforderung gegenüber das Menschrecht auf Zugang zu Sanitärversorgung umzusetzen. Es wird zunehmend akzeptiert, dass konventionelle Ansätze der Abwasserwirtschaft dieses Problem nicht lösen können. Die vorliegende Dissertation untersucht die Möglichkeit eines integrierten Ansatzes, welcher Stoffflüsse, Geldflüsse und Kommunikationsflüsse gemeinsam betrachtet und komplementär zu existierenden Infrastruktursystemen angewendet werden kann. Der Begriff „integriertes Sanitärsystem (iSaS)“ wird definiert und anhand eines Fallbeispiels in der Stadt Darkhan in der Mongolei untersucht. Hierbei wurde ein Sanitärsystem für Jurtensiedlungen erarbeitet, pilothaft umgesetzt und über 2 Jahre betrieben. Weiterhin wurde ein software- basiertes Modell anhand der Prinzipien von iSaS entwickelt und verschiedene Variationen des Systems untersucht und diskutiert. Das Modell kann an die klimatischen und sozioökonomischen Rahmenbedingungen in anderen Regionen der Welt angepasst werden und damit die potentielle Umsetzung von iSaS unterstützen. KW - Abwasser KW - Infrastruktur KW - Entwicklungsländer KW - Abfall KW - iPiT® KW - Mongolia KW - integrated sanitation system KW - new alternative sanitation systems NASS KW - UDDT Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170512-31794 ER - TY - THES A1 - Meyer-Kohlstock, Daniel T1 - Prospects for Biochar in a Bio-Waste Cascade N2 - In the early 2000s the pre-Columbian, anthropologically produced black soil in the Amazon basin, „Terra Preta de Índio“, received greater scientific attention. Compared to the surrounding poor soils, this very fertile anthrosol contains significantly higher levels of microorganisms and nutrients. The reason for this was determined to be the likewise high levels of charred biomass. This stable carbon, now called biochar, has since been intensively examined as an option to improve soil and to store carbon. Although the creation of Terra Preta was most likely based on a purposeful utilization of organic residues from households and gardens, biochar plays no role in the current recycling of bio-waste. However, the implementation of biochar could lead to many improvements. Results from agricultural research suggest that not only the yield capacity of soils can be increased but also the process performance of composting and biogas plants. The latter is especially relevant since currently about 40% of all collected bio-waste in Germany is recycled in an energy-material cascade consisting of anaerobic digestion and composting. The use of biochar in this cascade could then sequentially increase biogas yields, reduce greenhouse gas emissions, and improve compost quality. To realize the aforementioned advantages, the concept of biochar has to be integrated into the existing bio-waste cascade as practically as possible. This was done by the development of a theoretical scenario that allowed the analysis of energy and material flows to evaluate biochar’s recycling performance. Furthermore, the legal and economic framework were examined to assess the feasibility of the extended cascade and to suggest possible adjustments to the frameworks. KW - Kompost KW - Biogas KW - Pflanzenkohle Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20171108-36310 ER - TY - JOUR A1 - Alalade, Muyiwa A1 - Nguyen-Tuan, Long A1 - Wuttke, Frank A1 - Lahmer, Tom T1 - Damage identification in gravity dams using dynamic coupled hydro-mechanical XFEM JF - International Journal of Mechanics and Materials in Design N2 - Damage identification in gravity dams using dynamic coupled hydro-mechanical XFEM. KW - Angewandte Mathematik KW - Stochastik KW - Strukturmechanik Y1 - 2017 U6 - http://dx.doi.org/10.25643/bauhaus-universitaet.3596 SP - 1 EP - 19 ER - TY - JOUR A1 - Mehling, Simon A1 - Schnabel, Tobias A1 - Londong, Jörg T1 - Investigation on Energetic Efficiency of Reactor Systems for Oxidation of Micro-Pollutants by Immobilized Active Titanium Dioxide Photocatalysis JF - Water N2 - In this work, the degradation performance for the photocatalytic oxidation of eight micropollutants (amisulpride, benzotriazole, candesartan, carbamazepine, diclofenac, gabapentin, methlybenzotriazole, and metoprolol) within real secondary effluent was investigated using three different reactor designs. For all reactor types, the influence of irradiation power on its reaction rate and energetic efficiency was investigated. Flat cell and batch reactor showed almost similar substance specific degradation behavior. Within the immersion rotary body reactor, benzotriazole and methylbenzotriazole showed a significantly lower degradation affinity. The flat cell reactor achieved the highest mean degradation rate, with half time values ranging from 5 to 64 min with a mean of 18 min, due to its high catalysts surface to hydraulic volume ratio. The EE/O values were calculated for all micro-pollutants as well as the mean degradation rate constant of each experimental step. The lowest substance specific energy per order (EE/O) values of 5 kWh/m3 were measured for benzotriazole within the batch reactor. The batch reactor also reached the lowest mean values (11.8–15.9 kWh/m3) followed by the flat cell reactor (21.0–37.0 kWh/m3) and immersion rotary body reactor (23.9–41.0 kWh/m3). Catalyst arrangement and irradiation power were identified as major influences on the energetic performance of the reactors. Low radiation intensities as well as the use of submerged catalyst arrangement allowed a reduction in energy demand by a factor of 3–4. A treatment according to existing treatment goals of wastewater treatment plants (80% total degradation) was achieved using the batch reactor with a calculated energy demand of 7000 Wh/m3. KW - Fotokatalyse KW - Abwasserreinigung KW - photocatalysis KW - micro-pollutant treatment KW - titanium dioxid KW - reactor design KW - energy per order KW - OA-Publikationsfonds2022 Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20220912-47130 UR - https://www.mdpi.com/2073-4441/14/17/2681 VL - 2022 IS - Volume 14, issue 7, article 2681 SP - 1 EP - 15 PB - MDPI CY - Basel ER - TY - JOUR A1 - Söbke, Heinrich A1 - Lück, Andrea T1 - Framing Algorithm-Driven Development of Sets of Objectives Using Elementary Interactions JF - Applied System Innovation N2 - Multi-criteria decision analysis (MCDA) is an established methodology to support the decision-making of multi-objective problems. For conducting an MCDA, in most cases, a set of objectives (SOO) is required, which consists of a hierarchical structure comprised of objectives, criteria, and indicators. The development of an SOO is usually based on moderated development processes requiring high organizational and cognitive effort from all stakeholders involved. This article proposes elementary interactions as a key paradigm of an algorithm-driven development process for an SOO that requires little moderation efforts. Elementary interactions are self-contained information requests that may be answered with little cognitive effort. The pairwise comparison of elements in the well-known analytical hierarchical process (AHP) is an example of an elementary interaction. Each elementary interaction in the development process presented contributes to the stepwise development of an SOO. Based on the hypothesis that an SOO may be developed exclusively using elementary interactions (EIs), a concept for a multi-user platform is proposed. Essential components of the platform are a Model Aggregator, an Elementary Interaction Stream Generator, a Participant Manager, and a Discussion Forum. While the latter component serves the professional exchange of the participants, the first three components are intended to be automatable by algorithms. The platform concept proposed has been evaluated partly in an explorative validation study demonstrating the general functionality of the algorithms outlined. In summary, the platform concept suggested demonstrates the potential to ease SOO development processes as the platform concept does not restrict the application domain; it is intended to work with little administration moderation efforts, and it supports the further development of an existing SOO in the event of changes in external conditions. The algorithm-driven development of SOOs proposed in this article may ease the development of MCDA applications and, thus, may have a positive effect on the spread of MCDA applications. KW - Multikriteria-Entscheidung KW - Multikriterielle Entscheidungsanalyse KW - multi-criteria decision analysis; KW - set of objectives KW - crowdsourcing KW - platform KW - elementary interaction KW - OA-Publikationsfonds2022 Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20220713-46624 UR - https://www.mdpi.com/2571-5577/5/3/49 VL - 2022 IS - Volume 5, issue 3, article 49 SP - 1 EP - 20 PB - MDPI CY - Basel ER - TY - CHAP A1 - Fedior, Marco A1 - Hamel, Wido ED - Steiner, Maria ED - Theiler, Michael ED - Mirboland, Mahsa T1 - Simulationsumgebung zur Evaluation von umweltorientierten Verkehrsmanagement-Strategien T2 - 30. Forum Bauinformatik N2 - Der vorliegende Beitrag beschreibt die Problematik bei der Prognose verkehrsbedingter Schadstoff-Immissionen. Im Mittelpunkt steht die Entwicklung und der Aufbau einer Simulationsumgebung zur Evaluation von umweltorientierten Verkehrsmanagement-Strategien. Die Simulationsumgebung wird über die drei Felder Verkehr, Emission, Immission entwickelt und findet zunächst Anwendung in der Evaluation verkehrlicher Maßnahmen für die Friedberger Landstraße in Frankfurt am Main. KW - Verkehr KW - Simulation KW - Emission KW - Luftverunreinigender Stoff Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20190328-38678 ER - TY - THES A1 - Weitze, Laura Katharina T1 - Erweiterte Prozessbewertung von Biogasanlagen unter Berücksichtigung organoleptischer Parameter und Erfahrungswissen N2 - Landwirtschaftliche Biogasanlagen leisten mit ca. 9.300 Anlagen und einem Anteil von 5,3% an der Stromerzeugung, einen Beitrag zur Erzeugung Erneuer-barer Energien in Deutschland. Die Optimierung dieser Anlagen fördert die nachhaltige Bereitstellung von Strom, Wärme und BioErdgas. Das Ergebnis dieser Forschungsarbeit ist die Entwicklung eines mehrmethodi-schen Bewertungsansatzes zur Beschreibung der Qualität der Eingangs-substrate als Teil einer ganzheitlichen Prozessoptimierung. Dies gelingt durch die kombinierte Nutzung klassischer Analysesätze, der Nutzung organolepti-scher Parameter – der humansensorischen Sinnenprüfung – und der Integration von prozess- und substratspezifischem Erfahrungswissen. Anhand von halbtechnischen Versuchen werden Korrelationen und Kausalitäten zwi-schen chemisch-physikalischen, biologischen, organoleptischen und erfahrungsbezogenen Parametern erforscht. Die Entwicklung einer Fallbasis mit Hilfe des Fallbasierten Schließens, einer Form Künstlicher Intelligenz, zeigt das Entwicklungs- und Integrationspotenzial der Automatisierung auf, insbesondere auch im Hinblick auf neue Ansätze z.B. Industrie 4.0. Erste Lösungen zur Bewältigung der identifizierten Herausforderungen der mehrmethodischen Prozessbewertung werden vorgestellt. Abschließend wird ein Ausblick auf den weiteren Forschungsbedarf gegeben und die Übertragbarkeit des mehrmethodischen Bewertungsansatzes auf andere Anwendungsfelder z.B. Bioabfallbehandlung, Kläranlagen angeregt. N2 - Agricultural biogas plants significantly contribute to the generation of renewable energies in Germany. Approx. 9,300 facilities account 5.3% of the total generated electricity in Germany. Optimization of these biogas plants will undoubtably promote the sustainable provision of electricity, heat and natural gas. This research study developed a multi-methodical assessment approach to de-scribe the quality of input substrates as part of a holistic process optimization. This is achieved by combination of conventional analysis, use of organoleptic parameters, integration of process- as well as substrate-specific experient ba-sed knowledge. Correlations and causalities between chemical-physical, biological, organoleptic and experiential parameters are explored. These inves-tigations based on semi-technical experiments. Using case-based reasoning, a form of artificial intelligence, demonstrates the potential for development and integration of automation. Solving approaches to overcome the challenges of multi-methodical process assessment are presented. Finally, an outlook on further research needs is given. Furthermore, the trans-ferability of the multi-methodical assessment approach to other fields of application like bio-waste treatment or sewage treatment plants, is incited. KW - Biogasanlage KW - Erfahrungswissen KW - Maissilage KW - Optimierung KW - Biogas KW - Organoleptik Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20190129-38499 ER - TY - JOUR A1 - Londong, Jörg A1 - Barth, Marcus A1 - Söbke, Heinrich T1 - Modeling and Simulation of Source Separation in Sanitation Systems for Reducing Emissions of Antimicrobial Resistances JF - Water N2 - Antimicrobial resistance (AMR) is identified by the World Health Organization (WHO) as one of the top ten threats to public health worldwide. In addition to public health, AMR also poses a major threat to food security and economic development. Current sanitation systems contribute to the emergence and spread of AMR and lack effective AMR mitigation measures. This study assesses source separation of blackwater as a mitigation measure against AMR. A source-separation-modified combined sanitation system with separate collection of blackwater and graywater is conceptually described. Measures taken at the source, such as the separate collection and discharge of material flows, were not considered so far on a load balance basis, i.e., they have not yet been evaluated for their effectiveness. The sanitation system described is compared with a combined system and a separate system regarding AMR emissions by means of simulation. AMR is represented in the simulation model by one proxy parameter each for antibiotics (sulfamethoxa-zole), antibiotic-resistant bacteria (extended-spectrum beta-lactamase E. Coli), and antibiotic re-sistance genes (blaTEM). The simulation results suggest that the source-separation-based sanitation system reduces emissions of antibiotic-resistant bacteria and antibiotic resistance genes into the aquatic environment by more than six logarithm steps compared to combined systems. Sulfa-methoxazole emissions can be reduced by 75.5% by keeping blackwater separate from graywater and treating it sufficiently. In summary, sanitation systems incorporating source separation are, to date, among the most effective means of preventing the emission of AMR into the aquatic envi-ronment. KW - Abwasser KW - Ressourcen KW - microbial resistances KW - antimicrobial resistance genes KW - source separation KW - resource-oriented sanitation KW - UASB KW - OA-Publikationsfonds2021 Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20211202-45338 UR - www.mdpi.com/2073-4441/13/23/3342 VL - 2021 IS - Volume 13, issue 23, article 3342 SP - 1 EP - 19 PB - MDPI CY - Basel ER - TY - JOUR A1 - Söbke, Heinrich A1 - Lück, Andrea T1 - Framing Algorithm-Driven Development of Sets of Objectives Using Elementary Interactions JF - Applied System Innovation N2 - Multi-criteria decision analysis (MCDA) is an established methodology to support the decision-making of multi-objective problems. For conducting an MCDA, in most cases, a set of objectives (SOO) is required, which consists of a hierarchical structure comprised of objectives, criteria, and indicators. The development of an SOO is usually based on moderated development processes requiring high organizational and cognitive effort from all stakeholders involved. This article proposes elementary interactions as a key paradigm of an algorithm-driven development process for an SOO that requires little moderation efforts. Elementary interactions are self-contained information requests that may be answered with little cognitive effort. The pairwise comparison of elements in the well-known analytical hierarchical process (AHP) is an example of an elementary interaction. Each elementary interaction in the development process presented contributes to the stepwise development of an SOO. Based on the hypothesis that an SOO may be developed exclusively using elementary interactions (EIs), a concept for a multi-user platform is proposed. Essential components of the platform are a Model Aggregator, an Elementary Interaction Stream Generator, a Participant Manager, and a Discussion Forum. While the latter component serves the professional exchange of the participants, the first three components are intended to be automatable by algorithms. The platform concept proposed has been evaluated partly in an explorative validation study demonstrating the general functionality of the algorithms outlined. In summary, the platform concept suggested demonstrates the potential to ease SOO development processes as the platform concept does not restrict the application domain; it is intended to work with little administration moderation efforts, and it supports the further development of an existing SOO in the event of changes in external conditions. The algorithm-driven development of SOOs proposed in this article may ease the development of MCDA applications and, thus, may have a positive effect on the spread of MCDA applications. KW - Operations Research KW - multi-criteria decision analysis KW - elementary interaction KW - set of objectives KW - crowdsourcing KW - platform Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20220524-46469 UR - https://www.mdpi.com/2571-5577/5/3/49 VL - 2022 IS - Volume 5, issue 49, article 49 SP - 1 EP - 21 PB - MDPI CY - Basel ER -