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Design of an Integrated Robotic Reminder System for People with Dementia
No full textSeveral useful technologies to help people with dementia already exist. Robotic pets, for example, have been shown to alleviate negative symptoms associated with dementia. Most robotic pets, however, only have pet-like functionality. This is useful on its own, but adding additional care functionality would be helpful. A different useful tool for people with dementia is reminder systems. These systems can help them remember to do important daily tasks, like eating meals and taking medicine. These systems, however, usually use a phone as a medium. The user might leave their phone in another room, and if they do not take it to the location where the task is to be completed, they cannot check what the reminder was for. This thesis aims to combine these two systems, and presents the design of an integrated robot reminder system for people with dementia who live at home. It aims to address the problem of people with dementia forgetting important things, improve their quality of life, and reduce the stress experienced by their informal caregivers. The system consists of an animal-like robotic pet, which delivers reminders for important activities of daily living directly to the user with dementia. It guides them to a location in the house, where a screen tells them what the reminder is for. Through sensors placed in the house, the system can automatically detect whether some reminders have been completed, and can use contextual clues to send reminders at the best time. The research question for this thesis is “How can an integrated robotic reminder system effectively support people with dementia living at home in completing daily tasks while alleviating stress of their informal caregiver?”Three research topics are explored in the thesis. The first topic is that of value-sensitive design. The two main user groups, people with dementia and caregivers, both have values they want to see reflected in the system. Sometimes, these values may clash. The conflict between these values is explored in this thesis. Secondly, the interaction between the robot and the person in the context of a reminder system is researched. It should be clear to a user that the robot is trying to convey a reminder. The third topic relates to the software architecture and software engineering requirements. Private data should be stored securely, and the requirements should be written to make future development easy. Recommendations are made regarding the ideal setup of the system, ensuring proper security and usefulness. These technical choices were validated and improved through two interviews with experts in the field of privacy.The system was designed through an iterative process. In order to improve the system and validate its acceptability, two design workshops were held, one with professional caregivers and one with people with dementia living in a care home. We showed them a high-fidelity robot prototype, and showed the caregivers a user interface prototype for a caregiver app. These workshops showed that the combination of the robot and the reminder functionality was appealing, though not everyone was as interested.Computer Scienc
Land surface modeling informed by earth observation data: toward understanding blue–green–white water fluxes in High Mountain Asia
No full textMountains are important suppliers of freshwater to downstream areas, affecting large populations in particular in High Mountain Asia (HMA). Yet, the propagation of water from HMA headwaters to downstream areas is not fully understood, as interactions in the mountain water cycle between the cryo-, hydro- and biosphere remain elusive. We review the definition of blue and green water fluxes as liquid water that contributes to runoff at the outlet of the selected domain (blue) and water lost to the atmosphere through vapor fluxes, that is evaporation from water, ground, and interception plus transpiration (green) and propose to add the term white water to account for the (often neglected) evaporation and sublimation from snow and ice. We provide an assessment of models that can simulate the cryo-hydro-biosphere continuum and the interactions between spheres in high mountain catchments, going beyond disciplinary separations. Land surface models are uniquely able to account for such complexity, since they solve the coupled fluxes of water, energy, and carbon between the land surface and atmosphere. Due to the mechanistic nature of such models, specific variables can be compared systematically to independent remote sensing observations–providing vital insights into model accuracy and enabling the understanding of the complex watersheds of HMA. We discuss recent developments in spaceborne earth observation products that have the potential to support catchment modeling in high mountain regions. We then present a pilot study application of the mechanistic land surface model Tethys & Chloris to a glacierized watershed in the Nepalese Himalayas and discuss the use of high-resolution earth observation data to constrain the meteorological forcing uncertainty and validate model results. We use these insights to highlight the remaining challenges and future opportunities that remote sensing data presents for land surface modeling in HMA.Optical and Laser Remote Sensin
Data-Driven Optimal Control: An Inverse Optimization Model and Algorithm
No full textIn Inverse Optimization (IO), it is hypothesized that experts, when making decisions, implicitly engage in solving an optimization problem. If we can reconstruct this optimization problem using the decision data of the expert, then the behavior of the expert can be emulated. In this thesis, a novel inverse optimization model, Kernel Inverse Optimization Machine (KIOM), is proposed, utilizing kernel methods. Because its parameter space can be potentially infinite-dimensional, the model exhibits strong representation and generalization capabilities. Furthermore, empirical evidence is presented demonstrating the model’s ability to learn complex MuJoCo continuous control tasks. Subsequently, an algorithm for training KIOM, Sequential Selection Optimization (SSO), is proposed to address memory issues. SSO is a coordinate descent-based algorithm, and its memory requirements are nearly equal to the memory needed for solving one of its subproblems. Experimental results demonstrate that SSO converges to the optimal solution within a small number of iterations, highlighting itsefficiency.Mechanical Engineering | Systems and Contro
The multi-dimensional challenges of controlling respiratory virus transmission in indoor spaces: Insights from the linkage of a microscopic pedestrian simulation and SARS-CoV-2 transmission model
No full textSARS-CoV-2 transmission in indoor spaces, where most infection events occur, depends on the types and duration of human interactions, among others. Understanding how these human behaviours interface with virus characteristics to drive pathogen transmission and dictate the outcomes of non-pharmaceutical interventions is important for the informed and safe use of indoor spaces. To better understand these complex interactions, we developed the Pedestrian Dynamics—Virus Spread model (PeDViS): an individual-based model that combines pedestrian behaviour models with virus spread models that incorporate direct and indirect transmission routes. We explored the relationships between virus exposure and the duration, distance, respiratory behaviour, and environment in which interactions between infected and uninfected individuals took place and compared this to benchmark ‘at risk’ interactions (1.5 metres for 15 minutes). When considering aerosol transmission, individuals adhering to distancing measures may be at risk due to build-up of airborne virus in the environment when infected individuals spend prolonged time indoors. In our restaurant case, guests seated at tables near infected individuals were at limited risk of infection but could, particularly in poorly ventilated places, experience risks that surpass that of benchmark interactions. Combining interventions that target different transmission routes can aid in accumulating impact, for instance by combining ventilation with face masks. The impact of such combined interventions depends on the relative importance of transmission routes, which is hard to disentangle and highly context dependent.Transport and PlanningGame La
The impact of Marine and Offshore Renewable Energy on the European Energy System Evolution
No full textThe European energy transition policies aim to mitigate the effects of climate change by moving away from fossils and promoting both onshore and offshore renewable energy technologies. Although onshore renewables are driving the transition so far, policymakers believe that in order to achieve the targets, the power grid must have access to the theoretically abundant energy present in the oceans. More specifically, these targets suggest that by 2050, around the continent there should be at least 340 GW of marine and offshore renewables for EU member-states, in addition with 125 GW for the UK.The present study investigates the role of marine and offshore renewable technologies in 100\% renewable energy scenarios, inspired by the European targets of 2030, 2040 and 2050. The assessment of their role is based on he upgraded version of the open-source PyPSA-Eur (Python for Power System Analysis - European Sector, v0.25.1) energy system modelling tool developed within the Marine Renewable Energies Lab (MREL) of TU Delft, the PyPSA-MREL-TUD. This version is designed to have access on wave and farshore wind resources. The PyPSA framework utilizes an extract of the entire ENTSO-e transmission network and ERA5 climate data. By using time-series of 2018 for both the energy demand and weather data, this energy system model attempts to find cost-optimal solutions for the configuration of the different components of the power system. The developments include the addition of three wave energy converters and two types of floating offshore wind turbines to the existing generators and their associated costs, as well as the upgrade of the spatial resolution of the GEBCO bathymetry dataset of the model. For wave power, the model can access shallow water, nearshore and farshore wave resources, while for wind power both bottom fixed and floating generators are sub-categorized according to their distance from shore. Two significant constraints of the model include minimum generator capacity constraints for wind and wave power, and 70 \% energy equity per country.The analysis of the results focuses mainly on the generator and storage system configuration of the system. An emphasis was also given on the required expansion of the transmission grid, and the objective's investment and operational costs. What is initially observed is the impact of the spatial resolution of the ERA5 dataset on wave energy converter installations, which underestimated the energy potential profiles. Capacity constrained versions of the scenarios showed that wave energy has a higher average hourly market value, but is highly susceptible to seasonal patterns. Although the performance is better during colder periods, wave converters suffer the most during the warmer periods and are also the first generator type to be curtailed. While offshore wind turbines were installed all around the continent, with the best candidates being France, Baltic and Scandinavian countries, Greece and Romania, wave converters were installed mostly in Portugal, Ireland and Italy. However, the accessibility of every country to the sea basins varies. Country-specific analysis of the model implies that, for the 2050 horizon scenario, there is still a high level of dependability of landlocked countries on solar energy, on their neighbours and on storage systems. The overall line capacity must increase by a factor of two.Offshore and Dredging Engineerin
The design of permeable structures aimed at rehabilitating mangroves: A Case Study in Demak, Indonesia
No full textMangrove forests are highly valuable environments that offer numerous ecosystem services, including carbon storage, serving as nurseries for fish and shrimp, and providing timber. Additionally, these ecosystems offer coastline protection against erosion and flooding by attenuating waves and trapping sediment. Despite the crucial role of mangrove ecosystems, global mangrove cover has significantly declined in recent decades, with deforestation and coastal erosion being one of the contributing factors, launching a variety of initiatives for mangrove rehabilitation. To rehabilitate mangroves along eroding coastlines, permeable structures are designed as a solution. These structures dissipate incoming waves and reduce current strength, creating low-energy areas behind them that are conducive to sediment deposition. However, these structures frequently prove ineffective in the rehabilitation of mangroves, possibly due to the absence of clear design guidelines, and a lack of understanding regarding the influence of design parameters on the performance of these structures.This study, therefore, aimed to develop an integrated design guideline for permeable structures aimed at rehabilitating mangrove habitat along eroding coastlines by combining scientific knowledge with insights gleaned from pilot projects conducted globally. Furthermore, the research aimed to deepen understanding of the influence of design parameters on the performance of these permeable structures by conducting simulations of various structure configurations in a numerical, process-based model, and evaluating the performance of each configuration in reducing bed shear stress across the sheltered areas behind them. A nested model was employed in Delft3D-4, configuring the flow and wave modules to be coupled in order to incorporate the interaction between waves and currents.The developed conceptual framework and design guideline as well as the identified correlations between design parameters and structure performance in this study contribute to enhancing the design process of permeable structures aimed at rehabilitating mangrove habitat. It provides preliminary insights, highlights significant knowledge gaps and provides recommendations for further research, thereby opening up opportunities to expand knowledge surrounding the design of permeable structures aimed at morphodynamic restoration of mangrove habitat.Civil Engineering | Hydraulic Engineering | Hydraulic Structures and Flood Ris
Reduced-complexity Teleimpedance Command Interface Enabling Single-handed Control of 3D Stiffness for Unstructured Tasks
No full textThe state-of-the-art teleimpedance command interfaces used to command the robot stiffness configuration are either too complex to set up, such as those that use physiological signals and other tracking methods or cannot configure the stiffness appropriately for 3d environments.To mitigate these issues, a novel teleimpedance interface is proposed. The proposed interface can independently control the stiffness configuration's shape, orientation, and size with single-hand operations while allowing the operator to use that hand to command the robot's position. The teleimpedance interface is attached to the operator's hand and uses two scroll wheels, a joystick, and a force sensor to configure the robot's stiffness and has two different modes of operation.Compared to the state-of-the-art methods, the main advantage of the proposed teleimpedance command interface is that it does not require additional hardware with force feedback or complex setup calibrations while allowing for control of the robot's 3D stiffness configuration with single-handed operation.An experiment with human subjects was performed to demonstrate the proposed interface's acceptance and functionality.To demonstrate the teleimpedance command interface's ability to adjust 3D stiffness configurations a teleoperation was performed, utilizing a Kuka robotic arm and a Force Dimension Sigma7 position input interface.The teleimpedance interface functioned as intended during teleoperation in a 3D environment to configure and adjust the 3D stiffness configuration for the task in real-time.The results from the human subject trials indicate that the participants can successfully operate the interface to complete the alignment tasks in both modes for 3D stiffness configurations.Mechanical Engineering | Biomechanical Design - BioRobotic
Cybersecurity as a Crosscutting Concept Across an Undergrad Computer Science Curriculum: An Experience Report
No full textAlthough many Computer Science (CS) programs offer cybersecurity courses, they are typically optional and placed at the periphery of the program. We advocate to integrate cybersecurity as a crosscutting concept in CS curricula, which is also consistent with latest cybersecurity curricular guidelines, e.g., CSEC2017. We describe our experience of implementing this crosscutting intervention across three undergraduate core CS courses at a leading technical university in Europe between 2018 and 2023, collectively educating over 2200 students. The security education was incorporated within CS courses using a partnership between the responsible course instructor and a security expert, i.e., the security expert (after consultation with course instructors) developed and taught lectures covering multiple CSEC2017 knowledge areas. This created a complex dynamic between three stakeholders: the course instructor, the security expert, and the students. We reflect on our intervention from the perspective of the three stakeholders - we conducted a post-course survey to collect student perceptions, and semi-supervised interviews with responsible course instructors and the security expert to gauge their experience. We found that while the students were extremely enthusiastic about the security content and retained its impact several years later, the misaligned incentives for the instructors and the security expert made it difficult to sustain this intervention without organizational support. By identifying limitations in our intervention, we suggest ideas for sustaining it.Algorithmic
Bio-Based Plastics in Product Design: The State of the Art and Challenges to Overcome
No full textReplacing fossil-based feedstock with renewable alternatives is a crucial step towards a circular economy. The bio-based plastics currently on the market are predominantly used in single-use applications, with remarkably limited uptake in durable products. This study explores the current state of the art of bio-based plastic use in durable consumer products and the opportunities and barriers encountered by product developers in adopting these materials. A design analysis of 60 durable products containing bio-based plastics, and 12 company interviews, identified the pursuit of sustainability goals and targets as the primary driver for adopting bio-based plastics, despite uncertainties regarding their reduced environmental impact. The lack of knowledge of bio-based plastics and their properties contributes to the slow adoption of these materials. Furthermore, the lack of recycling infrastructure, the limited availability of the plastics, and higher costs compared to fossil-based alternatives, are significant barriers to adoption. Product developers face significant challenges in designing with bio-based plastics, but opportunities exist; for example, for the use of dedicated bio-based plastics with unique properties. When designing with bio-based plastics, product developers must think beyond the physical product and consider sourcing and recovery, which are not typically part of the conventional product design process.Design for Sustainabilit
Open code and data are not enough: Understandability as design goal for energy system models
No full textEnergy system models do not represent natural processes but are assumption-laden representations of complex engineered systems, making validation practically impossible. Post-normal science argues that in such cases, it is important to communicate embedded values and uncertainties, rather than establishing whether a model is 'true' or 'correct'. Here, we examine how open energy modelling can achieve this aim by thinking about what 'a model' is and how it can be broken up into manageable parts. Collaboration on such building blocks—whether they are primarily code or primarily data—could become a bigger focus area for the energy modelling community. This collaboration may also include harmonisation and intercomparison of building blocks, rather than full models themselves. The aim is understandability, which will make life easier for modellers themselves (by making it easier to develop and apply problem-specific models) as well as for users far away from the modelling process (by making it easier to understand what is qualitatively happening in a model—without putting undue burden on the modellers to document every detail).Energy and Industr