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Behavioral weight loss interventions for people with physical disabilities: A systematic review
No full textIncremental version control of distributed object models in the construction industry
No full textIn der Bauplanung bietet modellbasiertes Arbeiten deutliche Vorteile gegenüber zeichnungsbasierten Verfahren. Ein bisher kaum adressiertes Problem ist der Umgang mit Modellversionen, die im Zuge des nebenläufigen Engineerings entstehen. Diese Dissertation präsentiert einen Ansatz zur inkrementellen Versionskontrolle von BIM-Modellen. Die entwickelten Methoden nutzen Prinzipien der Graphentheorie und -transformation und ermöglichen den Austausch von Änderungen auf Objektebene.In construction planning, model-based procedures offer significant advantages over conventional drawing-based methods. A previously scarcely addressed issue is the handling of model versions that arise during concurrent engineering. This dissertation presents an approach to incremental version control of BIM models. The developed methods utilize principles of graph theory and transformation, enabling the exchange of changes at the object level
Collaborative Semantic Occupancy Prediction with Hybrid Feature Fusion in Connected Automated Vehicles
No full textCollaborative perception in automated vehicles leverages the exchange of information between agents, aiming to elevate perception results. Previous camera-based collaborative 3D perception methods typically employ 3D bounding boxes or bird's eye views as representations of the environment. However, these approaches fall short in offering a comprehensive 3D environmental prediction. To bridge this gap, we introduce the first method for collaborative 3D semantic occupancy prediction. Particularly, it improves local 3D semantic occupancy predictions by hybrid fusion of (i) semantic and occupancy task features, and (ii) compressed orthogonal attention features shared between vehicles. Additionally, due to the lack of a collaborative perception dataset designed for semantic occupancy prediction, we augment a current collaborative perception dataset to include 3D collaborative semantic occupancy labels for a more robust evaluation. The experimental findings highlight that: (i) our collaborative semantic occupancy predictions excel above the results from single vehicles by over 30%, and (ii) models anchored on semantic occupancy outpace state-of-the-art collaborative 3D detection techniques in subsequent perception applications, showcasing enhanced accuracy and enriched semantic-awareness in road environments
The Martingale Method for Optimal Investment with Random Endowment
No full textTypically, situations in which investors receive random endowments in addition to their standard wealth process turn out to be extremely challenging in terms of the mathematical analysis. This can also be seen in the paper „Optimal Investment with Time-Varying Stochastic Endowments “, where the authors approach the merton problem (utility maximization problem) for an investor receiving an additional random endowment with stochastic controls and the HJB equation. Even though this is a classical approach for dealing with the merton problem, it can be seen that very complex and technical arguments are needed to ensure a rigorous argumentation to reach the desired results. The idea of this master thesis now was to solve this problem with the so-called martingale method, hoping to have a more straight forward way with less technically constructed arguments. With the martingale method one splits up a utility maximization problem into two seperate problems: In a first part one actually applies the martingale method to determine the in terms of utility optimal achievable terminal payoff, as well as the existence of an admissible replicating strategy. This simplifies the optimization problem enormously, as instead of dealing with a complex stochastic process, one just solves a static optimization problem. As the martingale method just gives the existence of an optimal strategy, in a second step a concrete formula for that strategy is determined. The master’s thesis shows that the martingale method turns out to also beautifully work for the merton problem with random endowment. In opposite to the stochastic control approach, the argumentation is very straight forward and breaks down the complex incorporation of the random endowment into rather simple and understandable mathematics
Efficient Stereo Matching Using Swin Transformer and Multilevel Feature Consistency in Autonomous Mobile Systems
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Digital Twin Footprint - Erarbeitung eines ganzheitlichen Meilensteinplans mit Handlungsempfehlungen und notwendigen Forschungsbausteinen zur zielführenden Verknüpfung der Lebenszyklusanalyse (Gebäudeökobilanzierung) und BIM-Planungsprozesse mit einem Fokus auf den frühen Planungsphasen
No full textClimate neutrality and digitalisation – megatrends that are currently very popular and present the construction industry with new challenges. With a tightening of the EU's climate targets by 2030, the aim is to reduce greenhouse gas emissions by 55 % compared to 1990. The construction and building sector, being the largest greenhouse gas emitter, owns a key role here (Global Alliance for Buildings and Construction 2020). The continuous digital linking of the diferent process chains in the building planning process is able to decisively reduce environmental impact of the construction industry and lead to a sustainable and resource-saving transformation of the built environment. The Digital Twin Footprint research project is developing a milestone plan with recommendations for action and research modules to link life cycle analysis (building life cycle assessment) and the BIM planning process (BIM – Building Information Modelling) in the early planning phases of buildings. While in theory the construction and building sector is said to have a high potential for optimisation in terms of climate and environmental impact, in practice there is still a lack of holistic measures and specifcations. There are many reasons for this. Among other things, the focus often is only on purely energy-related measures, as previous political measures in the building sector have mainly addressed the increase of energy efciency and the use of renewable energies. By focussing on energy savings and the resulting emissions in the operating phase, the environmental impacts over the entire life cycle of a building are not recorded, although there is great potential for optimisation here. Material-bound CO2 emissions, often referred to as embodied carbon, can account for up to 80 % of the total, especially in the case of high energy efciency standards (RICS 2017). In order to be able to present and evaluate climate neutrality transparently and consistently, it is therefore necessary to carry out a complete calculation of CO2 emissions and other environmental impacts over the entire life cycle. According to the defnition of the German Sustainable Building Council (DGNB), buildings are defned as climate-neutral "if the diference between the emissions emitted and the emissions saved through production and provision of external CO2-free energy is zero or less than zero over a period of one year" (Deutsche Gesellschaft für Nachhaltiges Bauen – DGNB e.V. 2022). Novel and innovative approaches with an open data exchange strategy (Open-BIM) ofer a great added value to simplify the assessment with regard to the CO2 balance and make it applicable in practice. One of the most important methods in the feld of sustainable construction or to achieve climate neutrality is the Life Cycle Assessment (LCA). This method makes it possible to achieve CO2 and other environmental and resource-related optimisations over the entire life cycle, especially if the LCA is already used in the early planning phases. In building practice, however, this method has so far been used only rarely or only in sustainability certifcation systems for buildings. In these cases, the ecological balance is usually carried out too late, after the planning has been approved, which means that ecological optimisation potential can usually no longer be used. In addition, the technical building equipment is usually only taken into account in a generalised way and is underestimated (Lambertz et al. 2019). The main reason for this is the complexity of the application, as the necessary information and data procurement from the many project participants and databases is unstructured and mainly based on 2D planning documents (Gantner/Both et al. 2018).Thus, additional eforts for holistic, ecological building planning and renovation concepts are avoided, not least because of the supposedly too high complexity and costs. However, the BIM method in general and with regard to open data exchange formats, such as the Industry Foundation Classes (IFC), ofers great potential for carrying out life cycle assessments of buildings much more efciently and comprehensively (Theißen/Höper/Wimmer/Zibell et al. 2020). Due to the uniform structuring of the information required for the calculations and its easier accessibility within the BIM models, there is a high automation potential for carrying out a life cycle assessment of a building. The basis for this is a simple and standardised linking of the LCA data with BIM objects in the planning process (Höper 2020). Although there is already initial research and development in this area, the fndings have not yet been brought together or placed in a coordinated context. Many approaches are not directly practical and only work in their own software and research project environment. Although the frst LCA software products on the market enable a BIM-based calculation of the building life cycle assessment, they mainly only work with manufacturer-specifc data formats (closed BIM approach). The aim should be to implement BIM-integrated life cycle assessments in the open BIM approach with open and standardised data exchange formats. In this way, vendor neutrality and a diversity of the modelling and planning software systems used can be maintained depending on the discipline (Theißen/Höper/Drzymalla et al. 2020). Therefore, there is a great need to compile previous solution approaches from research but also from current practice in the BIM&LCA feld, to classify them with regard to their applicability and to evaluate and discuss advantages and disadvantages. The overall objective is to establish a high level of interoperability between BIM planning software solutions and the (ecological) specifc LCA data in the diferent planning phases. In this way, partially automated LCA calculations and optimisations can be carried out at an early stage and, at the same time, time-consuming and cost-intensive changes can be avoided in the later planning phases. Thus, within the framework of the Digital Twin Footprint project, it is important to analyse and compare previous principles, concepts and solutions in the area of BIM and LCA of buildings in order to create a common understanding and a coordinated, harmonised solution for a future, broad application of BIM-based LCA of buildings. This aspect is also relevant to avoid duplication of research and to create a harmony of research, practice and standardisation. In an expert workshop (AP2), the necessary adaptation and research requirements for diferent applications were concretised and prioritised in discourse with the experts. The findings were discussed and coordinated with various relevant viewpoints and perspectives, e.g. public institutions, BIM software representatives, LCA experts, etc., in order to prepare milestone planning and recommendations for action (AP3). In addition, the research potentials and topics for future and target-oriented proposal and contract research were identifed. To further break down the recommendations for action or adaptation needs, measures were formulated in AP3 that are necessary for a practical application of LCA with BIM. This was followed by identifcation of the levels of action or actors for whom it is proposed to implement the measures. With a classifcation in a timeline (short, medium, long term) and the efort, the relevance and feasibility of the measure should be highlighted. This will make it possible to support a future federal research strategy and practical application that promotes the iterative and planning-accompanying use of building life cycle assessment in order to be able to optimise buildings along the life cycle in terms of climate and environmental protection
Determining Riverine Surface Roughness at Fluvial Mesohabitat Level and Its Influence on UAV-Based Thermal Imaging Accuracy
No full textWater surface roughness (SR) is a highly relevant parameter governing data reliability in remote sensing applications, yet lacking appropriate methodology in riverine habitats. In order to assess thermal accuracy linked to SR of thermal imaging derived from an unmanned aerial vehicle (UAV), we developed the SR Measurement Device (SRMD). The SRMD uses the concept of in situ quantification of wave frequency and wave amplitude. Data of nine installed SRMDs in four different fluvial mesohabitat classes presented a range of 0 to 47 waves per 30 s and an amplitude range of 0 to 6 cm. Even subtle differences between mesohabitat classes run, riffle, and no-/low-flow still and pool areas could be detected with the SRMD. However, SR revealed no significant influence on the accuracy of thermal infrared (TIR) imagery data in our study case. Overall, the presented device expands existing methods of riverine habitat assessments and has the potential to produce highly relevant data of SR for various ecological and technical applications, ranging from remote sensing of surface water and habitat quality characterizations to bank stability and erosion risk assessments
Ecosystem services potential is declining across European capital metropolitan areas
No full textEcosystem services (ES) are essential to sustainable development at multiple spatial scales. Monitoring ES potential (ESP) at the metropolitan level is imperative to sustainable cities. We developed a procedure for long-term monitoring of metropolitan ESP dynamics, utilizing open-source land use land cover (LULC) data and the expert matrix method. We compared the ESP results of 38 European Capital Metropolitan Areas (ECMA) regarding biodiversity integrity, drinking water provision, flood protection, air quality, water purification, and recreation & tourism. Our results show significant declines in ESP across ECMA due to LULC alteration between 2006, 2012, and 2018. We found that ECMA in post-socialist European countries like Poland (Warszawa) have experienced high rates of land use transformation with a remarkable impact on ESP. Surprisingly, we found that Fennoscandinan ECMA, like Helsinki, Stockholm, and Oslo which lead the cumulative ESP ranking, faced the ESP reduction of the highest impact in recent years. The correlation analysis of ESP dynamics to urban expansion and population growth rates suggests that inattentive urbanization processes impact ESP more than population growth. We unveil the implications of our results to the EU and global level agendas like the European Nature Conservation Law and the Sustainable Development Goals