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Deep learning-based detection of marine images and the effect of data-driven influences
Get PDFThroughout recent years convolutional neural networks have been applied for various image detection tasks. Training data thereby plays an important role for the performance of those models. Not only the amount of images is crucial but also the number of annotations, classes as well as image dimensions. In view of changing underwater environments, the study of benthic communities is increasingly important especially in the Southern Ocean as they provide a key link for ecosystem shifts. This study concentrates on the automatic detection and classification of benthic species using deep learning. It could be shown that glass sponges, brittle stars and soft corals could successfully be detected even on few input data and highly biased class distributions in varying underwater scenes. Further analyses considering data-driven infuences show significant performance declines regarding the training on single objects and classes per image and the evaluation on large image dimensions.In den letzten Jahren wurden gefaltete neuronale Netze für verschiedene Aufgaben der Bilderkennung eingesetzt. Die Trainingsdaten spielen dabei eine wichtige Rolle für die Leistungsfähigkeit dieser Modelle. Dabei ist nicht nur die Menge der Bilder entscheidend, sondern auch die Anzahl der Annotationen, Klassen sowie die Bilddimensionen. Angesichts sich verändernder Unterwasserumgebungen wird die Untersuchung benthischer Lebensgemeinschaften vor allem im Südlichen Ozean immer wichtiger, da sie hier vor allem sensibel auf Veränderungen reagieren. Diese Arbeit konzentriert sich auf die automatische Erkennung und Klassifizierung von benthischen Arten mittels Deep Learning. Es konnte gezeigt werden, dass Glasschwämme, Schlangensterne und Weichkorallen selbst bei wenigen Eingabedaten und stark unterrepräsentierten Klassen in unterschiedlichsten Unterwasserlandschaften erfolgreich erkannt werden. Weitere Analysen zu datengetriebenen Einflüssen zeigen deutliche Leistungseinbußen bei einzelnen Objekten und Klassen pro Bild während des Trainings und großen Bilddimensionen während der Evaluation
Climate Improvement Districts - Potentiale und Risiken der stärkeren Einbindung von privaten Akteur*innen in den urbanen Klimaschutz
Get PDFIn dieser Arbeit wird das Gedankenexperiment Climate Improvement District (CID) hinsichtlich seiner Auswirkungen auf städtische Governance-Strukturen sowie seiner Potentiale für den Klimaschutz untersucht. Das Konzept CID basiert auf den in Deutschland seit 2005 praktizierten Business Improvement Districts (BID). In diesen schließen sich Grundeigentümer*innen zusammen und investieren in Maßnahmen die vornehmlich der Stärkung der Wirtschaftlichkeit des Quartiers dienen. Bei CIDs hingegen sollen Klimaschutzmaßnahmen im Vordergrund stehen.
Da CIDs bisher noch nicht umgesetzt wurden, werden in dieser Arbeit die (möglichen) Auswirkungen von solchen identifiziert und diskutiert. Hierfür wurde als einordnende Perspektive das Konzept Post-Democray verwendet. In einem empirischen Teil der Arbeit wurden zudem alle bisher in Hamburg durchgeführten BIDs hinsichtlich dem Aspekt Klimaschutz untersucht sowie Interviews mit verschiedenen Hamburger BID-Akteur*innen geführt
Öffentliche Ladeinfrastruktur Hamburg - Prozess- und Wirkungsevaluation und bedarfsgerechte Weiterentwicklung
Get PDFHamburg hat 2014 mit Hilfe stadteigener Gesellschaften mit dem Aufbau einer bedarfsgerechten Ladeinfrastruktur begonnen. Mit dem Ziel das Henne-Ei-Problem zu lösen erfolgte die Bereitstellung der Ladeinfrastruktur durch die öffentliche Hand zeitlich vorgelagert zum Fahrzeughochlauf. Mit der Einführung von Direktbezahlmöglichkeiten ohne Vertragsbindung, einem diskriminierungsfreien Zugang und Ladestationen auch in Randlagen wurde ein nutzerfreundliches System etabliert. Eine politische Rückendeckung, Innovationskraft und positive Fehlerkultur zählen zu den wichtigsten Erfolgsmerkmalen. Ein kontinuierlicher Lernprozess führte zu stetigen Prozessoptimierungen. Knapp 250.000 Ladevorgänge konnten für das Jahr 2019 verzeichnet werden, wobei die Belegungszahl pro Tag pro Ladestation bei 1,4 Fahrzeugen liegt. Eine stärkere Auslastung ist im Zentrum und an Standorten mit hoher Dichte an Points of Interest zu beobachten. In Wohnquartieren nutzen Laternenparker das öffentliche Ladenetz. Weitere Hotspots entstehen durch e-Carsharing. Für den Ausbau empfiehlt sich die Fokussierung auf Nachfrageschwerpunkte, Anpassung des Standortmodells auf Basis von Korrelationsanalysen und Faktorengewichtung, präzisierte Bedarfsermittlung und der Abbau praktischer Hemmnisse. In den kommenden Jahren ist außerdem mit einer Expansion von Ladeinfrastruktur außerhalb des öffentlichen Raumes zu rechnen
Introduction: Great Transformation, Actors and Theoretical Contexts
Get PDFIn diesem Kapitel werden die Beiträge von Planungsakteuren sowie anderen staatlichen und nicht-staatlichen Akteuren zur großen Transformation untersucht. Akteuren und Akteursbeziehungen kommt bei der Nachhaltigkeitstransformation eine maßgebliche Bedeutung zu, da sie in einem Wechselverhältnis mit den strukturellen Rahmenbedingungen stehen: Welches Veränderungspotenzial hat das Handeln von Akteuren innerhalb existierender Strukturen und inwieweit können Akteure Strukturen in Richtung einer nachhaltigen Entwicklung beeinflussen? Das Kapitel nimmt theoretische Bezüge von Transition Management, Multi-Level-Perspective sowie Governance auf und analysiert das Wirken von Akteuren und ihre Beiträge zur großen Transformation in ausgewählten Handlungsfeldern: Siedlungsentwicklung und Flächenverbrauch, Wohnen, Digitalisierung und Smart City, Ernährungssysteme sowie räumliche Planung. Im Ergebnis behandelt der Beitrag die Fragen, a) welche Rolle Akteure und dabei insbesondere solche der räumlichen Planung sowie andere staatliche und nicht-staatliche Akteure für die Transformation spielen, b) wie besonders staatliche Akteure im Sinne eines gestaltenden Staates zur Transformation beitragen können, c) welche Beiträge durch Strategien und Instrumente der Stadt- und Raumentwicklung sowie -planung geleistet werden, und d) welche förderlichen und hinderlichen Faktoren Transformationsprozesse bzw. das Wirken von Akteuren beeinflussen. Zusammenfassend lässt sich festhalten, dass der Politik und der Verwaltung, einschließlich der formellen und informellen Planung, eine zentrale Rolle zukommt, Strukturen und Bedingungen zu schaffen, die es ermöglichen, dass staatliche Akteure sich entwickeln können und nicht-staatliche Akteure in öffentlichen und insbesondere Planungsstrukturen Resonanz finden, um wirksame Schritte in Richtung einer großen Transformation zu gehen. Gleichzeitig wird aber auch deutlich, dass in dem Handlungsfeld der großen Transformation nicht-staatliche Akteure eine besondere Rolle einnehmen, wenn sie als "Pioniere des Wandels" auftreten und Impulse geben. Diese können in ein Wechselspiel mit den staatlichen Akteuren treten und unterstützende Rahmenbedingungen in Politik und Verwaltung sowie ermöglichende ökonomische Dynamiken und (positive) Pfadabhängigkeiten nutzen. Aus der Akteursperspektive ist es für die große Transformation daher förderlich, wenn in der nachhaltigen Raumentwicklung Synergien zwischen Akteuren identifiziert, entsprechende Schnittstellen für gemeinsames Handeln ausgebaut und daraus Anforderungen an eine transformative Governance abgeleitet werden.This chapter investigates the contributions to the great transformation of planning actors and other state and non-state actors. Actors and the relationships between them are of great significance in the transformation towards sustainability, as they interact with structural parameters: what is the potential for changing the behaviour of actors within existing structures and to what extent can actors influence structures to encourage sustainable development? The chapter draws theoretically on transition management, multi-level perspectives and governance, and analyses the impact of actors and their contributions to the great transformation in selected fields: settlement development and land take, housing, digitalisation and the Smart City, food systems and spatial planning. The chapter thus considers a) which role is played in the great transformation by actors, especially those involved in spatial planning but also other state and non-state actors, b) how state actors in particular can contribute to transformation in line with the notion of a formative state, c) what contributions are made through the strategies and instruments of urban and spatial development and planning, and d) which factors promote and which hinder transformation processes or the impact of actors. To sum up, it can be stated that politics and administration, including formal and informal planning, have a central role to play. They create the structures and parameters necessary for state actors to develop and for non-state actors in public and particularly in planning positions to find the support necessary for effective steps towards a great transformation to be taken. At the same time it is also clear that non-state actors also have a significant role to play in the great transformation when they emerge as "pioneers of change" providing transformative impulses. Such actors can interact with state actors, profiting from supportive frameworks in politics and administration and making use of enabling economic dynamics and (positive) path dependencies. In terms of the role of actors, it is clear that the great transformation can profit from the identification of synergies between actors in sustainable spatial development and the expansion of interfaces for joint action, thus allowing the requirements of transformative governance to be derived
Bathymetric Survey for Enhancing the Volumetric Capacity of Tagwai Dam in Nigeria via Leapfrogging Approach
Get PDFFrom a global perspective, dams are constructed to trap water flowing from a higher concentration to a lower concentration into a basin for several purposes to aid humanity. The continuous monitoring of dams is prudent for measuring the rate of sedimentation and siltation, and to ensure that it functions to its full capacity. The Tagwai dam is used for irrigation and domestic activities. It was observed that there is a shortage in its storage capacity and supplies due to sedimentation, and coupled with this is the fact that the majority of the communities are not connected to the tap water system; if not, the problem would have been evidently pronounced. However, to determine the present volume of water and provide possible ways of increasing the reservoir’s storage capacity, the leapfrogging approach was used to improve the basin. The data were collected using a single beam echosounder and Hi-Target V30 differential global positioning system (DGPS). The sounder was used to acquire bathymetric data, while the DGPS was used to delineate the shoreline. The data were interpolated using the ordinary Kriging technique. After that, the leapfrogging method was grouped into four scenarios: Scenario A, B, C, and D. In each stage, the volume was computed using Simpson’s 3/8 integrated model. Scenario A is the present stage of the reservoir. Consequently, the results show that, while scenario B and C presented an appreciable increase in volume at the instant, scenario D illustrated a tremendous improvement in the storage capacity, and it is a win-win situation. The decision on which leapfrogging approach to employ depends on the government’s willingness to enhance the reservoir’s capacity and the resources available, such as human and financial capital to execute the project
L5IN: Overview of an Indoor Navigation Pilot Project
Get PDFWhile outdoor navigation systems are already represented everywhere, the enclosed space is much less developed. The project Level 5 Indoor Navigation (L5IN) presents a new approach with mobile phone standard 5G as the orientation signal and without additional infrastructure for navigation in indoor environments. The aim of this project is to use the new available 5G technology to show how navigation systems, which have thus far only been available in the outdoor segment, can now be integrated into existing smartphone systems for indoor navigation. This paper gives an overview of the project and presents the different work packages leading to a holistic approach towards the development of an indoor navigation application for pedestrians. By using a specific app with open interfaces, it is planned to make navigation possible in all buildings modeled according to certain standards. The challenge involved is that, unlike outdoor maps, there is no map basis for buildings. For this reason, different approaches to map generation were examined. In a building information model (BIM), all information will be collected and made available via a database for positioning and visualization. The focus is furthermore on positioning, achieved through smartphone sensors and 5G, so that users can orientate themselves in buildings without having to connect to singular systems. It shall be shown that positioning with a standard deviation of 2–3 m and a confidence interval of 68 % is possible. Another advantage of 5G, the ability to send real-time data in higher data packages, will be used for data transmission. The basic idea of 5G-based indoor navigation will be enabled with radio cells of the providers, which will be set up on the HafenCity University campus. The complex university building will be used as a prototype environment
An Underwater Photogrammetric Application to Generate Micro-Bathymetry Data for Benthic Habitat Mapping and Analysis at Arctic Ocean
Get PDFThe Ocean Floor Observation and Bathymetry System (OFOBS) is an underwater survey platform, which is designed and developed for research in the Polar Regions by the Alfred Wegener Institute (AWI). The tailored deep tow system brought a new perspective and clarity from Arctic Ocean by its optical and acoustic sensors. During the PS101 expedition at the Karasik seamount, OFOBS provides a novel picture of megafauna’s habitats. In this study, we develop a methodology to convert the imagery dataset to micro-bathymetry in order to provide primary data for object detection and habitat mapping which will provide a better understanding of arctic benthic habitats. The methodology is based on the underwater photogrammetry workflow and two different point cloud classification methods adopted for sponge detection in 3D point clouds, to facilitate habitat mapping with a focus on the central of Karasik seamount where an extensive and dense assemblage of the Geodia sponges is dominating the seafloor
Glass Strength for Impact and Blast Loading
Get PDFGlass strength is highly influenced by strain rate. This material behaviour is well known in structural glass design and implemented in various standards. The strength of architectural glass is determined by component tests with a defined strain rate of 2 N/(mm2s), providing favourable terms for testing. As typical effects of actions on facades result in lower or higher strain rates, a strain rate factor must be implemented in structural design standards. Standard load cases as dead load, snow, climate and wind inducing low strain rates have been determined with sufficient accuracy by analytical models and extensive component testing. In difference, extensive experimental studies under higher strain rates are missing to cover accidental design situations as impact and blast. Here, only few test series are documented with a small number of test specimens, so that a statistical evaluation was not possible. Therefore, experimental tests are presented in this study, investigating the glass strength of annealed glass, heat strengthened glass and fully tempered glass under low-speed and high-speed conditions. To obtain statistical reliable experimental data, 160 glass specimens were tested, having stress rates in the relevant specimen center zones of 2 N/(mm2s) and 1,400 N/(mm2s). The surfaces of most specimens were pretreated with corundum to reduce the variation of glass surface bending strength. Further to verification of conducted tests by theoretical damage accumulation (risk integral method), load duration factors for impact and blast load design are proposed up to 1.12 for fully tempered glass and 1.4 for heat strengthened glass. On the basis of this results and other research, sufficient data are available to adapt load duration factors for impact and blast in structural design codes
Space needed to make a city sustainable and necessary changes to reach it: the case of Germany
Get PDFA city concentrates humans, apartments, services, factories, and other facilities. The city is in permanent exchange with its surrounding, receiving food, energy, water, materials and others while delivering products, formation etc. If that whole process would run in a way that it can run in the same way for all future generations, the city would be a sustainable one. As a consequence, it is not adequate to regard only the city scale; the city has to be investigated together with its surrounding. This paper investigates what a sustainable city could be. Starting from the human needs a liveable city is sketched regarding its density and internal organisation, land use, buildings, and their arrangement. The potential of harvesting renewable energies and food per land unit is estimated. The present demand leads to an immense need of land to cover it. To reach sustainability, three different strategies are possible: (a) keep the demand like it is; (b) reduce the demand by increasing efficiency; or (c) reduce the demand by a change of the lifestyle; and cover for (a) to (c) the remaining demand with renewable systems. The highest potential for strategy (b) is in the building sector (refurbishment) and transportation (electrical machines), (c) is touched for food production (widely vegetarian nutrition). Assuming that these changes are already realized, the demand of land for renewable production of energy and food is determined based on corresponding literature and statistical data. For Germany, the need of land exceeds the available land still by 50%. Strategies (a) and (b) led to a big improvement, but without strategy c) the target cannot be reached. That confirms the assumption that the available land for food production and harvest of renewable energies could prove oneself as another limited resource that might be even the dominant one
