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The Iberian Peninsula comprises one of the largest boundaries between Mediterranean and Eurosiberian vegetation, known as sub-Mediterranean zone. This ecotone hosts many unique plant species and communities and constitutes the low-latitude (warm) margin of numerous central European species which co-occur with Mediterranean vegetation. Two of the main species found in this region are the Eurosiberian European beech (Fagus sylvatica L.) and the Mediterranean Pyrenean oak (Quercus pyrenaica Willd.). It remains unclear how the different physiological and adaptive strategies of these two species reflect their niche partitioning within a sub-Mediterranean community and to what extent phenotypic variation (intraspecific variability) is driving niche partitioning across Eurosiberian and Mediterranean species. We quantified functional niche partitioning, based on the n-dimensional hypervolume to nine traits related to resource acquisition strategies (leaf, stem and root) plus relative growth rate as an additional whole-plant trait, and the environmental niche similarity between Pyrenean oak and European beech. Further, we analyzed the degree of phenotypic variation of both target species and its relationship with relative growth rates (RGR) and environmental conditions. Plant recruitment was measured for both target species as a proxy for the average fitness. Species’ functional space was highly segregated (13.09% overlap), mainly due to differences in niche breadth (59.7%) rather than niche replacement (25.6%), and beech showed higher trait variability, i.e., had larger functional space. However, both species shared the environmental space, i.e., environmental niches were overlapped. Most plant traits were not related to abiotic variables or RGR, neither did RGR to plant traits. Both target species share similar environmental space, however, show notably different functional resource-use strategies, promoting a high complementarity that contributes to maintaining a high functionality in sub-Mediterranean ecosystems. Therefore, we propose that conservation efforts be oriented to preserve both species in these habitats to maximize ecosystem functionality and resilience.
Linking functional composition moments of the sub-mediterranean ecotone with environmental drivers
(2023)
Functional trait-based approaches are extensively applied to the study of mechanisms governing community assembly along environmental gradients. These approaches have been classically based on studying differences in mean values among species, but there is increasing recognition that alternative metrics of trait distributions should be considered to decipher the mechanisms determining community assembly and species coexistence. Under this framework, the main aim of this study is to unravel the effects of environmental conditions as drivers of plant community assembly in sub-Mediterranean ecotones.
We set 60 plots in six plant communities of a sub-Mediterranean forest in Central Spain, and measured key above- and belowground functional traits in 411 individuals belonging to 19 species, along with abiotic variables. We calculated community-weighted mean (CWM), skewness (CWS) and kurtosis (CWK) of three plant dimensions, and used maximum likelihood techniques to analyze how variation in these functional community traits was driven by abiotic factors. Additionally, we estimated the relative contribution of intraspecific trait variability and species turnover to variation in CWM. The first three axes of variation of the principal component analyses were related to three main plant ecological dimensions: Leaf Economics Spectrum, Root Economics Spectrum and plant hydraulic architecture, respectively. Type of community was the most important factor determining differences in the functional structure among communities, as compared to the role of abiotic variables. We found strong differences among communities in their CWMs in line with their biogeographic origin (Eurosiberian vs Mediterranean), while differences in CWS and CWK indicate different trends in the functional structure among communities and the coexistence of different functional strategies, respectively. Moreover, changes in functional composition were primarily due to intraspecific variability. We observed a high number of strategies in the forest with the different communities spreading along the acquisitive-conservative axis of resource-use, partly matching their Eurosiberian-Mediterranean nature, respectively. Intraspecific trait variability, rather than species turnover, stood as the most relevant factor when analyzing functional changes and assembly patterns among communities. Altogether, our data support the notion that ecotones are ecosystems where relatively minor environmental shifts may result in changes in plant and functional composition.
The material authenticity of cultural heritage has been questioned by societies in which the modern paradigm of conservation has not developed from within the native culture. This paper examines the philosophical and practical traditions in Iran regarding the materiality and authenticity of past structures. By reviewing the emergence of the Western conservation paradigm in Iran, this paper highlights two key factors: the rapidness of this paradigm shift and the remarkable contradiction between the new and old paradigms. By borrowing the Deleuzo-Guattarian concept of a ‘body without organs’ (BwO), this paper problematises the rapidness and radicality of the paradigm shift in Iran. It suggests exploring the under-investigated possibilities between the pre-modern and modern paradigms to address the gap between native circumstances and Western standards.
Urban heritage planning in Tehran and beyond : sequences of disrupted spatial-discursive assemblages
(2023)
Despite the impact of ideological rigidity, the primary challenge of heritage planning in Tehran and beyond lies not in the dominance of an inflexible Authorized Heritage Discourse, but rather in the absence of stable spatial-discursive and administrative structures. Solmaz Yadollahi maps the historical trajectory of conservation and urban heritage planning in Iran, depicting a discursive-spatial assemblage that tends to knock down its accumulated resources. This is in line with Katouzian's portrayal of Iran as a pick-axe society. Residing within this society, the studied assemblage strives to deconstruct the prevailing structures and usher in a fresh one, paradoxically perpetuating the very cycle it seeks to escape.
Morphological and optical properties of a multilayer film (CAZO/CZAO/ZACO) prepared by spin-coating method and deposited on a glass substrate were evaluated. The study was initially carried out for each layer, individually and then as a multilayer subsequently. Structural properties using X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), infrared spectra (IR) and X-ray photoelectron Spectroscopy (XPS) showed the presence of three phases of zinc, copper and silver oxides at different levels. The CZAO sample observed with scanning electron microscope (SEM) showed an excellent porous surface with a large deformation in the multilayer configuration. Doping with zinc and copper in the silver crystal lattice improved the crystal structure and reduced the optical energy gap, thus increasing the optical absorbance and refractive index. The dielectric constants and showed an increase in the optical polarization values for lower photonic energies. The maximum degradation rate for photocatalysts of methylene blue was 89 % for a 5-h exposure period with CAZO/CZAO/ZACO while it reached 71 % for the CZAO sample during the same time period. The sensitivity of samples to light proved that the presence of ultraviolet radiation increases the number of holes trapped by oxygen ions and causes more free electrons and contribute to a better production of photocurrent than in darkness.
1. Zweite Änderungssatzung zur fachspezifischen Prüfungs- und Studienordnung für den Bachelor-Studiengang Biotechnologie (B. Sc.) vom 15. März 2024
2. Lesefassung: Fachspezifische Prüfungs- und Studienordnung für den Bachelor-Studiengang Biotechnologie (B. Sc.) vom 30. Juli 2018 (AMbl. 15/2018) i. d. F. der Zweiten Änderungssatzung zur fachspezifischen Prüfungs- und Studienordnung für den Bachelor-Studiengang Biotechnologie (B. Sc.) vom 15. März 2024
1. Erste Änderungssatzung zur fachspezifischen Prüfungs- und Studienordnung für
den Bachelor-Studiengang Medizintechnik vom 15. März 2024
2. Lesefassung: Fachspezifische Prüfungs- und Studienordnung für den Bachelor-Studiengang Medizintechnik vom 04. Oktober 2022 i. d. F. der ersten Änderungssatzung zur Prüfungs- und Studienordnung für den Bachelor-Studiengang Medizintechnik vom 15. März 2024
A contribution to the online monitoring of partial discharges in high-voltage grid components
(2024)
Increasing utilization of HV power cable lines, and particularly the advent of long HVDC underground links, results in the need to sensitively monitor their condition, such as by tracking the emergence and development of partial discharges. This study demonstrates that existing solutions are poorly suited to the case of HVDC lines, and that a new, more sophisticated monitoring system needs to address a wide array of diverse problems. First of all, the overview of the task and main functional blocks of the monitoring system is given. Following this, selected blocks are subject to detailed examination in subsequent chapters.
The first of these blocks, a high-frequency current transformer (HFCT), is responsible for capturing the signal in the power line and transferring it to the electronics. This component receives in-depth coverage: general design considerations, computation of leakage inductance, operation in presence of a power current, resonant behavior, balanced design. Particular attention is given to the application of Finite Element Analysis (FEA) in relation to the HFCT, however, the demonstrated techniques can also be applied to other magnetic devices. Last section of the chapter presents various stages of development, experimental setups, prototypes, and the final device which has been put into series production.
The next block addresses extraction of signals from noise. A literature analysis is conducted concerning noise suppression in partial discharge recordings, and the application of the signal separation approach based on Linear Predictive Coding is shown.
In the section on localization, examples illustrating problems encountered during the development of a partial discharge localization algorithm are presented.
In the chapter devoted to laboratory tests, various auxiliary experiments conducted during the system's development are compiled, where some of them are: Time Domain Reflectometry (TDR) TDR-based line characterization, estimation of monitoring sensitivity, measurement of the cable attenuation and reflection coefficients of the accessories.
In the final chapter – field tests – the installation of the system on a 110 kV line and the measured transfer function are demonstrated.
Kleinstädte stehen vor der Herausforderung, die Lebensqualität und die Lebenszufriedenheit ihrer Bewohner:innen zu verbessern. Dabei sind subjektive Wahrnehmungen oft wichtiger als objektive Maßstäbe. Im Rahmen dieser Studie werden deshalb die Attraktivitätsfaktoren von Kleinstädten untersucht, die dazu beitragen, die Lebensqualität der Bürger:innen zu fördern. Um ein realistisches Bild auf die Anforderungen der Bewohner:innen zu erhalten, ist es wesentlich, die tatsächlichen Aktivitätsräume der Kleinstadt-Bewohner:innen zu betrachten. Mit Blick auf die individuelle Beurteilungs- und Einstellungsebene der Bürger:innen wird deshalb eine erweiterte geografisch-räumliche Perspektive eingenommen. Für Bürger:innen ist im Rahmen ihres Well-Beings der Raum entscheidend, in dem sie sich normalerweise bewegen. Ihr Radius überschreitet dabei typischerweise die Grenzen der eigenen Kleinstadt und bezieht das nähere regionale Umfeld mit ein. Vor diesem Hintergrund wurde in dem Projekt die Frage adressiert, wie die spezifischen Eigenschaften von Kleinstädten sowie ihr regionales Umfeld die Lebensqualität und Zufriedenheit ihrer Bewohner:innen im Vergleich zu Großstadtbewohner:innen beeinflussen. Um diese Frage zu beantworten, wurde eine Kombination aus qualitativer und quantitativer Forschung angewendet. Im ersten Schritt wurden zwei Fokusgruppendiskussionen in einer dezentral gelegenen Kleinstadt bzw. einer zentral gelegenen Kleinstadt durchgeführt. Im zweiten Schritt erfolgte eine quantitativ orientierte Fragebogenstudie in diesen beiden Kleinstädten und in einer Vergleichs-Großstadt, bei der insgesamt 1.144 Personen befragt wurden. Dabei wurden Daten zur Attraktivität der Städte, ihres regionalen Umfelds und zur Lebensqualität und Zufriedenheit der Bewohner:innen von Kleinstädten im Vergleich zu Großstädten erhoben und analysiert. Die Ergebnisse der Studie zeigen, dass Bürger:innen sowohl lokale als auch regionale Angebote nutzen und sich v.a. im Hinblick auf Bedürfnisse des Alltags und der (Grund-) Versorgung Angebote in der Nähe ihres Wohnorts wünschen. Die untersuchten Kleinstädte weisen dabei in Bezug auf Qualitätsfaktoren wie z.B. die Umwelt- und Wohnqualität eine höhere Attraktivität aus Sicht der eigenen Bewohner:innen auf als die betrachtete Großstadt. Die Studie hat gezeigt, dass Kleinstädte durch die Nutzung regionaler Ressourcen und die Integration digitaler Möglichkeiten eine hohe Lebensqualität bieten können, obwohl sie selbst nicht immer alle benötigten Angebote vorhalten können und dass die Lebenszufriedenheit in den Kleinstädten zum Teil höher ist als in der betrachteten Vergleichs-Großstadt. Gerade zentral gelegene Kleinstädte können dabei von der Nähe zu größeren Städten und den damit verbundenen Vorteilen profitieren. Langfristig spielt auch die Digitalisierung eine Rolle, indem sie den Zugang zu entfernten Dienstleistungen und Produkten erleichtert und bestehende Nachteile von Kleinstädten mit Blick auf ihre Ausstattung abmildern kann.
Die Basis der gegenwärtigen und zukünftigen pflegerischen Entwicklung wurzelt im fortlaufenden Prozess der Aktion und Reflexion. Der Dialog zwischen „Praxis“ und „Theorie“ als Fundament der Begegnung mit anderen und sich selbst, mit denen täglich auf implizite, intuitive und tazide Wissensbestände zurückgegriffen wird, in der die Kunst darin besteht, sich reflektierend Wissens- und Erfahrungsbeständen anzunähern. In einer Pflegewelt, in denen Praxisanleiter_innen im WIR-DU-ICH sich unserer Verantwortung bewusst sind, in denen Du die pflegerischen Situationen einschätzt und ich als Praxisanleiter_in mit dem Team pädagogische Prozesse mit ausgestalte, als mein gesellschaftlicher pflegerischer Auftrag, mit dem Ziel Menschen in den jeweiligen Lebensphasen begleiten zu können. Praxisanleiter_innen reflektieren „Selbstverständliches“ während ihrer pflegerischen Beziehungsgestaltung mit dem zu Pflegenden, so dass die angehenden Pflegenden, Anhaltspunkte in konkreten pflegerischen Situationen für die Entscheidungsprozesse erhalten. Mit dem zugrundeliegenden Subjektverständnis einer demokratischen Bildungsarbeit verstehen sich alle Beteiligten als sich stetig entwickelnd. Exemplarische Grundlage der Bildungsarbeit bieten die 10-jährigen Erfahrungsbestände in der Bildungspraxis an einer brandenburgischen Hochschule, die illustriert wie sich bspw. die Studierenden, die Praxisbegleiter_innen und die Praxisanleiter_innen auf den Lernort „Praxis“ vorbereiten, so dass Kompetenzen gefördert und gestärkt werden. Mit einer Vision der Zukunft schließt der gegenwärtige Entwicklungsprozess aller Beteiligten mit der Handreichung für Praxisanleiter_innen zur Begleitung berufspraktischer Studienphasen ab. Das Schreiben ist formell abgeschlossen, aber der informelle Dialog wird fortgesetzt, um die aktuelle Situation aufrechtzuerhalten.
Plenty of semiconductor devices are developed to operate with private data. To guarantee data privacy cryptographic algorithms are used, where the secrecy is based on the used keys. Theoretically, the cryptographic algorithms using keys with recommended lengths are secure. The issue is that a potential attacker can steal the devices and attack in a lab. Physical attacks are usually aimed to perturb normal operation of a device and to extract cryptographic keys, e.g. by means of fault injection (FI). One class of FI attacks exploits the sensitivity of semiconductor devices to light and are performed using a laser as the light source.
This work investigates the sensitivity of different logic and memory cells to optical Fault Injection attacks. Front-side attacks against cells manufactured in different IHP technologies were performed using two different red lasers controlled by Riscure software. To reach the repeatability of the experimental results and to increase the comparability of the results with attack results published in literature the setup parameters as well as setting parameters of the Riscure software were experimentally evaluated. Attacks were performed against inverter, NAND, NOR, flip-flop cells from standard libraries, radiation-hard flip-flops based on Junction Isolated Common Gate technique, radiation-tolerant Triple Modular Redundancy registers as well as non-volatile Resistive Random Access Memory (RRAM) cells. The results of attacks against volatile circuits were successful transient bit-set and bit-reset as well permanent stuck-at faults. The results of attacks against RRAM cells were successful in the sense that manipulation of all RRAM logic states was feasible. The faults injected during the performed experiments were repeatable and reproducible.
The goal of this work was not only to achieve successful FI but also to determine cell area(s) sensitive to laser illumination. Knowledge about areas sensitive to laser illumination can be used by designers to implement corresponding countermeasure(s) at the initial stage of chip development and is the necessary step to design appropriate countermeasures. For example, metal fillers can be applied as optical obstacles reducing the success of front-side FI attacks, i.e. as a possible low-cost countermeasure. Based on the knowledge of the sensitive cell areas, the placement of the metal fillers can be automated in the future, i.e. the findings given in the work can serve as a basis for a methodology development for improving resistance against optical FI attacks at the initial stage of chip development. Such methodology can be adapted for each chip manufacturing technology.
The 'cultural appropriation' of traditional textiles from Mexico : an analysis of 3 case studies
(2023)
This doctoral thesis intended to examine the phenomenon of ‘cultural appropriation’ of traditional textiles from Mexico through an analysis of 3 case studies. This research had the objective of understanding the phenomenon through the relationships, perspectives, and discourses of the social actors involved, by following the development of controversies involving different objects of material culture from different communities: the xaam nïxuy Ayuujk (Mixe) blouse from Santa Maria Tlahuitoltepec, Oaxaca; the Hñuhú and Hñahñ (Otomi) “Tenango” embroideries from the communities of Tenago de Doria and San Nicolas in Hidalgo; and the mestizo gabanes from Santa Clara del Cobre and Nahuatzen in the State of Michoacán.
This doctoral examination was sustained through theoretical approximations that located the occurrences within transnational/ transcultural processes, engaging with qualitative methodologies and multi-sited ethnographies in order to obtain data that elucidated on the diversity of objects, actors, relationships, understandings, perceptions, values, and discourses involved in the ‘cultural appropriation’ of traditional textiles controversies in the country.
The content analysis of this doctoral research dissected a number of different processes, effects, and consequences of the phenomenon as it developed in dissimilar locations and periods of time. The examination revealed a complex intersection of meanings, productions, circulations, and consumptions of culture, that simultaneously affected cultural meanings, relationships, and processes, raising concerns over the management of traditional textiles as objects of cultural heritage, and the unviability of protecting communal creative domains through national legal mechanisms.
The development of computer technologies allows using numerical simulations in the early stages of aircraft design more and more often. The role of both wind tunnels and initial test flights used to validate of solutions seems to be diminishing. Big systems for three-dimensional simulations of Fluid-Structure Interactions (FSI) constitute highly specialized and costly software. Most of the codes are based on many simplifications. One of them is the assumption of linearity of the structural model being in contradiction with real-life situations. The postdoctoral dissertation presents the results of simulations for complex, multi-scale objects and non-linear structure models and extended structure testing in relation to damage in macroscale analysis. What is crucial for carrying out the assumed analyses is to extend a numerical tool comprising a flow and a structural program and a space grid deformation model for a system allowing to take into consideration the non-linearity of the structure. The point of reference for testing the suggested approaches are the existing solutions of the aeroelastic linear problems. Results of the recent research might be applied for the construction of increasingly common unmanned aerial vehicle (UAV). Modern structure is a key element that affects the basic parameters as mass or range of these vehicles. Until now the research and development of the aeroelastic calculation algorithm for commonly used materials in the framework of linear geometry and linear-elastic material behavior was used. The current developments of materials for light-weight design common use of 3D printing technology causes the increasingly widespread use of new alternative materials in the aviation industry. This is particularly true for the design and construction of UAV, where the basic requirements are the lightness of the structure and the maximum range. Unfortunately, the fulfillment of the above criteria means that the materials used are often loaded not only in a elastic range but also more often above this limit. In case of analyzing aeroelastic phenomena for a loaded structure we should take a closer look at the behavior of the material outside the elastic range in which the damage occurs. The process of destroying in the face of such dangerous phenomena as flutter in aircraft constructions requires a deeper analysis of the mechanics of materials, in particular for new materials and their manufacturing techniques. As part of joint experiments and numerical simulations, detailed research was carried out to describe the behavior of printed materials, which will be increasingly used in the design of aircraft structures. Extending the postdoctoral dissertation with the research carried out at BTU will allow further development of the existing FSI algorithm, taking into account the structural behavior more accurately and the possibility of predicting damage processes.
The contribution of community involvement in heritage management : a cultural mapping project
(2023)
Heritage has been lately the matter of debate regarding its definition, conservation and management approaches. In the last few years, there has been an increasing demand for the involvement of the local community in heritage management. Too often, the involvement perspectives of key stakeholders in general and the community members, in particular, are entirely different. While the theoretical ground of community involvement is somehow well set, heritage management has been slow in applying the involvement approach. Practically, it is not easy to find the balance to achieve all the goals of key stakeholders in any involvement project. Subsequently, there are a few numbers of empirical works on the practical implications of understanding heritage management effective tools and limited indication to convince recent ‘power-holders’ such as governmental organizations to distribute their power with local community members.
This doctoral research project explores community involvement in heritage management as an effective solution to building a strong management system. The study aims to examine the level and the quality of involvement in the management of heritage sites in general through a cultural mapping-based approach. This is applied to a case study which is the Religious Complex in Historic Cairo World Heritage Site. The research outcomes indicate the importance of involving the local community in heritage management and planning processes. Ultimately, the study provides critical empirical evidence and draws valuable theoretical and practical assumptions that spread knowledge of cultural mapping in critical issues, such as the drivers of involvement and cooperative decision-making.
Brain-computer interfacing (BCI) is a relatively new field of study that involves engineering, neuroscience, psychology, and physiology. A BCI is a system that allows direct communication between the brain and the environment, using signals from electroencephalography (EEG) to identify a user's intentions and mental states. This can be used for human-machine interaction (HMI) to adapt software or control a device. Particularly passive BCIs are the most promising for the general population, as they can detect and interpret a user's mental state without requiring their attention. This can enable neuroadaptive technology (NAT), which allows a machine to learn over time how the user perceives and interprets the world. However, there are still obstacles to be overcome before BCI technology can be applied in real-world situations for NAT.
In this work I firstly address the issue of subject dependence in training data collection for classifier calibration, which can be time-consuming and impractical. I investigated the training of a subject-independent predictive model that is trained on a group of other users' data and applied to online-testing data of a new person. This was done in the context of training an automatic classifier for error detection and correction. Results showed that a classifier model can be trained without user-specific calibration and with high accuracy. The number of electrodes used in training the model was also reduced. Further it was validated that the trained classifier models were based on cortical sources and not other modalities.
In a second study I address the issue of task-dependence. To that end I tested the application of a potentially task-independent calibration paradigm for mental workload assessment in a new task. This new task was a speed reading context, where subjects read texts of varying difficulty and speed. The study found that the mental workload prediction model was accurate in classifying mental workload in different reading tasks, indicating that it can be used as a task-independent classifier for mental workload.
In a third study I examine if it is possible to measure neural correlates of human moral assessment using a passive BCI on a single-trial basis. A calibration paradigm was developed using pictures that were ranked as morally unacceptable and morally neutral. However, the results showed low classification accuracies and it was not possible to reliably distinguish between a user's subjective moral evaluations on a single-trial basis using current classification approaches.
The results presented in this thesis provide solutions towards real-world applicability of NAT enabled by passive BCIs, as examples of a subject-independent and a task-independent classifier are demonstrated and discussed. Further, approaches for increased versatility of passive BCI technology are presented, that could make passive BCIs more feasible for use in future real-world human-machine interaction settings.
Die vorliegende Studie möchte einen Beitrag zur Erforschung der Frage leisten, inwiefern Rechtsformwechsel bei Stiftungen Auswirkungen auf das Commitment der Beschäftigten haben. Der Fokus liegt dabei auf den Wechselabsichten des Personals beziehungsweise auf dem Absentismus. Im Rahmen einer qualitativen Forschung wurden drei Stiftungen betrachtet, in denen ein Rechtsformwechsel stattgefunden hat. Die Untersuchung wurde mittels Expert/-inneninterview durch eine semistrukturierte Befragung anhand eines Interviewleitfadens durchgeführt. Die Auswertung der Daten erfolgte durch eine qualitative Inhaltsanalyse per QDA-Software. Dabei konnte festgestellt werden, dass bei Einhaltung der Maßnahmen zur Stärkung des Commitments wenige und dann nur positive Auswirkungen zu erkennen sind, da sich Fehlzeiten und Absentismus nicht wesentlich veränderten. Für die Praxis ist relevant, dass die Vorteile der Änderung der Rechtsform einer Stiftung gegenüber den Risiken überwiegen. Weitere Forschungsbedarf,besteht hinsichtlich des nachlassenden Engagements beim Personal im Hinblick auf Änderungen.
Cities are major contributors to climate change and biodiversity loss, and at the same time particularly affected by some of their consequences. Urban green can help address these challenges and provide numerous other benefits to people. Economic valuation can estimate the value that people assign to these diverse urban ecosystem services. The environmental economics literature uses several valuation methods. This work examines the valuation of urban ecosystem services with choice experiments. It includes five articles that use empirical analysis to address three overarching research goals: First, to improve understanding of the value of urban ecosystem services to urban residents. Second, to contribute to improving the validity of choice experiments. Third, to develop modeling of spatial patterns in the value of urban ecosystem services.
Chapter 1 describes the background and motivation of the valuation of urban ecosystem services with choice experiments, gives an overview over the relevant literature, and sets out the research objectives and methods of this dissertation.
Chapter 2 presents a choice experiment on green spaces, street trees and green roofs in Bremen. It analyzes the effect of additional information that these measures are part of a climate adaptation strategy. The results show greater willingness to pay among informed respondents. Part of the effect can be explained by a higher credibility of the survey.
Chapter 3 describes a choice experiment on urban gardens in Berlin and Stuttgart. It explores how respondents process the information provided in the questionnaire. It finds that questions about the information do not significantly affect either recall or the responses in the choice experiment.
Chapter 4 is based on choice experiments on street trees, green spaces, and greenways in four German cities. It examines how choice experiment surveys should elicit perceived consequentiality. The results show advantages of elicitation before the choice experiment over the usual elicitation afterwards.
Chapter 5 explores how valid policy makers perceive the results of choice experiments on urban green in several German cities, and what consequences this has for their use of the results. Interviews show that most policy makers use the results in their city to raise awareness or justify positions. Perceptions of validity are mixed, but do not play a major role in this type of use.
Chapter 6 examines the spatial distribution of the value of urban ecosystem services using choice experiments on green spaces, urban trees, green roofs, and green facades in Berlin and Leipzig. It develops and tests new choice models that may better represent than the common approach how the value of urban green space decreases with distance.
Based on the findings of the articles, Chapter 7 derives recommendations for practitioners of choice experiments and for urban green policy makers. Finally, it identifies research gaps that would be promising for future studies.
There are many names we use to call them, like the (original) Wireless Sensor Networks, Wireless Sensor and Actuator Networks, Internet of Things, Cyber-Physical Systems, Cyber-Physical Systems of Systems, and some others. More or less visible, wireless sensor networks are already applied in many aspects of our lives and for different purposes. During the 20 years of Fachgespräch Sensornetze (FGSN) we were able to observe the process of the birth and evolution of wireless sensor networks. What do they look like now, from that time perspective? Is there still room for research andimprovements? Or are they maybe already that mature that everything has already been said? And what do they look like from the industry point of view? What is the future of sensor networks? Where are they heading? These retrospective and perspective views are the central topic of the 20th edition of the Fachgespräch Sensornetze (FGSN 2023) held on the 4th of September 2023 at Hasso-Plattner-Institut as part of the NetSys 2023 conference in Potsdam. We were happy to meet again, to discuss these subjects within the scientific community. The aim of this series of Fachgespräch is to give scientists from academia and industry the opportunity for an informal exchange of ideas and to strengthen cooperation in this multidisciplinary research area.