Institut Geomatik

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Grenzen des Grundeigentums
(Hochschule für Architektur, Bau und Geomatik FHNW, 14.06.2024) Akeret, Aurelio; Gamma, Christian; Huser Bau- und Immobilienrecht
Die zunehmende vertikale Siedlungs- und Infrastrukturentwicklung wird die bereits bestehenden Interessenskonflikte zwischen Privateigentum und öffentlicher Hand weiter verschärfen. Die amtliche Vermessung (AV) bildet für viele Planungen die Grundlage, erfasst jedoch die bebaute Umwelt lediglich zweidimensional und bestimmt nur die horizontale Abgrenzung der Grundstücke. Die dritte Dimension ist im aktuellen Plan für das Grundbuch nicht berücksichtigt. Das Schweizerische Zivilgesetzbuch (Art. 667 Abs. 1) definiert das Eigentum nach oben und nach unten, soweit ein Interesse an dessen Ausübung besteht. Diese Arbeit befasst sich primär mit zwei Herausforderungen: Erstens mit dem technischen Problem der dreidimensionalen Darstellung und zweitens mit der administrativ-rechtlichen Problematik der Definition des Grundeigentums in den Luftraum und den Untergrund. Daraus ergibt sich die Frage, wie 3D-Grundeigentum in der Schweiz definiert und dargestellt werden könnte. Durch Interviews mit Fachleuten auf Stufe Bund, Kantone, Unternehmen und Fachpersonen werden in dieser Arbeit wichtige Erkenntnisse zur Optimierung der aktuellen Grundeigentumsdefinition gesammelt. Es hat sich gezeigt, dass der Bedarf an einer dreidimensionalen Darstellung sowohl rechtlich als auch darstellungstechnisch klar vorhanden ist. Eine Mehrheit der interviewten Personen ist der Meinung, dass die bisherige Grundeigentumsumschreibung Unklarheiten schafft und eine vertikale Grenze sinnvoll wäre. Das Grundeigentum wird folglich auf Basis der Interviewanalysen und der Hinzunahme juristischer Referenzlektüre nach oben und nach unten fixiert und in Raumzonen entsprechend den unterschiedlichen Nutzungsmöglichkeiten unterteilt. Um das Grundeigentum vertikal zu definieren und somit die Grundlage für einen 3D-Eigentumskataster zu schaffen, ist eine politische Unterstützung unerlässlich. Es ist anzunehmen, dass eine Gesetzesänderung erforderlich sein wird, um das Grundeigentum vertikal zu definieren. Dies stellt einen zentralen und notwendigen Schritt dar. Auch der Verfasser dieser Arbeit teilt diese Ansicht. Die Fachwelt ist gefordert, den erzeugten Mehrwert durch eine vertikale Grundeigentumsdefinition respektive eines 3D-Eigentumskatasters überzeugend und klar zu kommunizieren.
11 - Studentische Arbeit
IND-AV: Nutzungsspezifische Informationsanforderungen an die Daten der amtlichen Vermessung
(Hochschule für Architektur, Bau und Geomatik FHNW, 12.01.2024) Glaus, Silvan; Gamma, Christian; Bundesamt für Landestopografie swisstopo, Eidgenössische Vermessungsdirektion
Die Masterthesis greift grundlegende Prozesse und Lösungsansätze aus der Studie zur Überprüfung des Konzepts Nutzungsspezifische Informationsanforderungen an die Daten der amtlichen Vermessung (IND-AV) von Schildknecht et al. (2021) auf und unterzieht sie einer kritischen Bewertung aus praxisbezogener Sicht. Die Bewertung erfolgt anhand von zwölf durchgeführten Interviews mit Fachexpertinnen und Fachexperten aus dem Bereich der amtlichen Vermessung. Die Interviews werden anhand einer qualitative Inhaltsanalyse nach Mayring-Fenzl ausgewertet. Die Ergebnisse geben einen umfassenden Überblick, wie die verschiedenen Elemente des IND-AV-Konzepts beurteilt werden und welche offenen Fragen noch geklärt werden müssen. Dabei wird deutlich, dass die Bewertung des Konzepts aus praxisbezogener Sicht erheblich variiert. Während einige Aspekte als vorstellbar und mit erkennbarem Mehrwert betrachtet werden, gibt es Bereiche, in denen der Mehrwert nicht offensichtlich ist oder deren Sinn von den Befragten nicht vollständig verstanden wird. Neben den Interviews liegt der Schwerpunkt der Masterthesis auf der Anwendung der Berechnungsformel zur Bestimmung des Lagecodes des IND-AV-Konzepts. Diese Formel wird in vier charakteristisch unterschiedlichen Gemeinden angewendet. Die resultierenden Lagecodes werden mit den Toleranzstufen in Beziehung gesetzt und verglichen. Zudem erfolgt eine umfassende Untersuchung der Homogenität der Toleranzstufeneinteilung. Die Analyse der Toleranzstufeneinteilung offenbart eine Vielzahl von Sachverhalten, in denen die Handhabung der Toleranzstufen in den verschiedenen Kantonen uneinheitlich erfolgt. Im Gegensatz dazu ermöglicht die Berechnungsformel zur Bestimmung des Lagecodes eine automatisierte und einheitliche Festlegung der lagespezifischen Kriterien, welche die Informationsanforderungen der amtlichen Vermessung vorgeben. Die Ergebnisse verdeutlichen, dass der Lagecode deutlich detaillierter als die Toleranzstufen ist. Er erfüllt dabei exakt den prognostizierten Zweck, höhere Informationsanforderungen dort zu fordern, wo sie tatsächlich benötigt werden: Die Fläche der Gebiete mit hohen Informationsanforderungen nimmt ab, während gleichzeitig die Anzahl der Objekte in diesen Gebieten steigt. Allerdings werden nahezu alle Objekte einer einzelnen Objektklasse dem gleichen Lagecode zugeordnet. Daher wäre es denkbar, anstelle des Lagecodes die Informationsanforderungen pro Objektklasse festzulegen und künftig auf das Lagekriterium zu verzichten.
11 - Studentische Arbeit
Building aggregation to estimate the potential for shared energy generation with heat pumps
(Copernicus Publications, 21.06.2023) Bereuter, Pia; Hall, Monika
04B - Beitrag Konferenzschrift
Charting everyday activities in later life. Study protocol of the mobility, activity, and social interactions study (MOASIS)
(Frontiers Research Foundation, 24.01.2023) Röcke, Christina; Luo, Minxia; Bereuter, Pia; Katana, Marko; Fillekes, Michelle; Gehriger, Victoria; Sofios, Alexandros; Martin, Mike; Weibel, Robert
Prominent theories of aging emphasize the importance of resource allocation processes as a means to maintain functional ability, well-being and quality of life. Little is known about which activities and what activity patterns actually characterize the daily lives of healthy older adults in key domains of functioning, including the spatial, physical, social, and cognitive domains. This study aims to gain a comprehensive understanding of daily activities of community-dwelling older adults over an extended period of time and across a diverse range of activity domains, and to examine associations between daily activities, health and well-being at the within- and between-person levels. It also aims to examine contextual correlates of the relations between daily activities, health, and well-being. At its core, this ambulatory assessment (AA) study with a sample of 150 community-dwelling older adults aged 65 to 91 years measured spatial, physical, social, and cognitive activities across 30 days using a custom-built mobile sensor (“uTrail”), including GPS, accelerometer, and audio recording. In addition, during the first 15 days, self-reports of daily activities, psychological correlates, contexts, and cognitive performance in an ambulatory working memory task were assessed 7 times per day using smartphones. Surrounding the ambulatory assessment period, participants completed an initial baseline assessment including a telephone survey, web-based questionnaires, and a laboratory-based cognitive and physical testing session. They also participated in an intermediate laboratory session in the laboratory at half-time of the 30-day ambulatory assessment period, and finally returned to the laboratory for a posttest assessment. In sum, this is the first study which combines multi-domain activity sensing and self-report ambulatory assessment methods to observe daily life activities as indicators of functional ability in healthy older adults unfolding over an extended period (i.e., 1 month). It offers a unique opportunity to describe and understand the diverse individual real-life functional ability profiles characterizing later life.
01A - Beitrag in wissenschaftlicher Zeitschrift
Square-glyphs. Assessing the readability of multidimensional spatial data visualized as square-glyphs
(Taylor & Francis, 2023) Müller, Gianna; Hollenstein, Daria; Cöltekin, Arzu; Bleisch, Susanne
Glyphs have long been used to approach the challenge of visualising multidimensional data with geospatial reference. Depending on the glyph design, data-dense visualizations of several concurrent data dimensions can be created. The square-glyph is a compound glyph to represent up to four data dimensions, e.g. walkability indices, with reference to a gridded geographic space (Bleisch and Hollenstein 2018 [Exploring multivariate representations of indices along linear geographic features. Proceedings of the 2017 International Cartographic Conference, Washington D.C. (pp. 1–5)]). In this paper, we present a user study to evaluate the readability and interpretability of the square-glyphs. We compare user performance with square-glyph plots containing two and four simultaneously mapped data dimensions under different value compositions. Our results show that the user performance with square-glyphs does not decrease as the number of data dimensions represented increases from two to four. The study results indicate no significant differences in efficiency and effectiveness between the four-dimensional square-glyphs and the two-dimensional square-glyphs. The average values of five adjacent glyphs can be estimated with a mean error of eight percentage points. The results suggest that equal value distances between the displayed dimensions are more accurately perceived in a lower-value composition than in higher-value arrangements.
01A - Beitrag in wissenschaftlicher Zeitschrift
Silage bale detection for the «Cultivable Area» update of the Cantonal Agricultural Office, Thurgau
(Institut Geomatik, Hochschule für Architektur, Bau und Geomatik FHNW, 09/2022) Adrian F. Meyer; Jordan, Denis
In Switzerland direct subsidies are paid to farms for sustainable agricultural practice. The cultivable agricultural area layer (German: Landwirtschaftliche Nutzfläche, LN) serves as an annual basis for the calculation of these contributions at the Swiss cantonal agricultural offices. Material deposits like silage bale stacks are usually excluded from the LN. Therefore, the canton of Thurgau could profit from a spatial vector layer indicating locations and area consumption extent of silage bale stacks intersecting with the LN perimeter.
05 - Forschungs- oder Arbeitsbericht
(Near) real-time snow water equivalent observation using GNSS refractometry and RTKLIB
(MDPI, 2022) Steiner, Ladina; Studemann, Géraldine Laurence; Grimm, David; Marty, Christoph; Leinss, Silvan
Global navigation satellite system (GNSS) refractometry enables automated and continuous in situ snow water equivalent (SWE) observations. Such accurate and reliable in situ data are needed for calibration and validation of remote sensing data and could enhance snow hydrological monitoring and modeling. In contrast to previous studies which relied on post-processing with the highly sophisticated Bernese GNSS processing software, the feasibility of in situ SWE determination in post-processing and (near) real time using the open-source GNSS processing software RTKLIB and GNSS refractometry based on the biased coordinate Up component is investigated here. Available GNSS observations from a fixed, high-end GNSS refractometry snow monitoring setup in the Swiss Alps are reprocessed for the season 2016/17 to investigate the applicability of RTKLIB in post-processing. A fixed, low-cost setup provides continuous SWE estimates in near real time at a low cost for the complete 2021/22 season. Additionally, a mobile, (near) real-time and low-cost setup was designed and evaluated in March 2020. The fixed and mobile multi-frequency GNSS setups demonstrate the feasibility of (near) real-time SWE estimation using GNSS refractometry. Compared to state-of-the-art manual SWE observations, a mean relative bias below 5% is achieved for (near) real-time and post-processed SWE estimation using RTKLIB
01A - Beitrag in wissenschaftlicher Zeitschrift
AI-based 3D detection of parked vehicles on a mobile mapping platform using edge computing
(2022) Meyer, Jonas; Blaser, Stefan; Nebiker, Stephan
In this paper we present an edge-based hardware and software framework for the 3D detection and mapping of parked vehicles on a mobile mapping platform for the use case of on-street parking statistics. First, we investigate different point cloud-based 3D object detection methods on our extremely dense and noisy depth maps obtained from low-cost RGB-D sensors to find a suitable object detector and determine the optimal preparation of our data. We then retrain the chosen object detector to detect all types of vehicles, rather than standard cars only. Finally, we design and develop a software framework integrating the newly trained object detector. By repeating the parking statistics of our previous work (Nebiker et al., 2021), our software is tested regarding the detection accuracy. With our edge-based framework, we achieve a precision and recall of 100% and 98% respectively on any parking configuration and vehicle type, outperforming all other known work on on-street parking statistics. Furthermore, our software is evaluated in terms of processing speed and volume of generated data. While the processing speed reaches only 1.9 frames per second due to limited computing resources, the amount of data generated is just 0.25 KB per frame.
04B - Beitrag Konferenzschrift
Outdoor mobile mapping and AI-based 3D object detection with low-cost RGB-D cameras. The use case of on-street parking statistics
(MDPI, 05.08.2021) Nebiker, Stephan; Meyer, Jonas; Blaser, Stefan; Ammann, Manuela ; Rhyner, Severin
A successful application of low-cost 3D cameras in combination with artificial intelligence (AI)-based 3D object detection algorithms to outdoor mobile mapping would offer great potential for numerous mapping, asset inventory, and change detection tasks in the context of smart cities. This paper presents a mobile mapping system mounted on an electric tricycle and a procedure for creating on-street parking statistics, which allow government agencies and policy makers to verify and adjust parking policies in different city districts. Our method combines georeferenced red-green-blue-depth (RGB-D) imagery from two low-cost 3D cameras with state-of-the-art 3D object detection algorithms for extracting and mapping parked vehicles. Our investigations demonstrate the suitability of the latest generation of low-cost 3D cameras for real-world outdoor applications with respect to supported ranges, depth measurement accuracy, and robustness under varying lighting conditions. In an evaluation of suitable algorithms for detecting vehicles in the noisy and often incomplete 3D point clouds from RGB-D cameras, the 3D object detection network PointRCNN, which extends region-based convolutional neural networks (R-CNNs) to 3D point clouds, clearly outperformed all other candidates. The results of a mapping mission with 313 parking spaces show that our method is capable of reliably detecting parked cars with a precision of 100% and a recall of 97%. It can be applied to unslotted and slotted parking and different parking types including parallel, perpendicular, and angle parking.
01A - Beitrag in wissenschaftlicher Zeitschrift
Brain network integration dynamics are associated with loss and recovery of consciousness induced by sevoflurane
(Wiley, 2021) Luppi, Andrea I.; Golkowski, Daniel; Ranft, Andreas; Ilg, Rüdiger; Jordan, Denis; Menon, David K.; Stamatakis, Emmanuel A.
The dynamic interplay of integration and segregation in the brain is at the core of leading theoretical accounts of consciousness. The human brain dynamically alternates between a sub‐state where integration predominates, and a predominantly segregated sub‐state, with different roles in supporting cognition and behaviour. Here, we combine graph theory and dynamic functional connectivity to compare resting‐state functional MRI data from healthy volunteers before, during, and after loss of responsiveness induced with different concentrations of the inhalational anaesthetic, sevoflurane. We show that dynamic states characterised by high brain integration are especially vulnerable to general anaesthesia, exhibiting attenuated complexity and diminished small‐world character. Crucially, these effects are reversed upon recovery, demonstrating their association with consciousness. Higher doses of sevoflurane (3% vol and burst‐suppression) also compromise the temporal balance of integration and segregation in the human brain. Additionally, we demonstrate that reduced anticorrelations between the brain's default mode and executive control networks dynamically reconfigure depending on the brain's state of integration or segregation. Taken together, our results demonstrate that the integrated sub‐state of brain connectivity is especially vulnerable to anaesthesia, in terms of both its complexity and information capacity, whose breakdown represents a generalisable biomarker of loss of consciousness and its recovery.
01A - Beitrag in wissenschaftlicher Zeitschrift
Toward flexible visual analytics augmented through smooth display transitions
(Elsevier, 2021) Tominski, Christian; Andrienko, Gennady; Andrienko, Natalia; Bleisch, Susanne; Fabrikant, Sara Irina; Mayr, Eva; Miksch, Silvia; Pohl, Margit; Skupin, André
Visualizing big and complex multivariate data is challenging. To address this challenge, we propose flexible visual analytics (FVA) with the aim to mitigate visual complexity and interaction complexity challenges in visual analytics, while maintaining the strengths of multiple perspectives on the studied data. At the heart of our proposed approach are transitions that fluidly transform data between user-relevant views to offer various perspectives and insights into the data. While smooth display transitions have been already proposed, there has not yet been an interdisciplinary discussion to systematically conceptualize and formalize these ideas. As a call to further action, we argue that future research is necessary to develop a conceptual framework for flexible visual analytics. We discuss preliminary ideas for prioritizing multi-aspect visual representations and multi-aspect transitions between them, and consider the display user for whom such depictions are produced and made available for visual analytics. With this contribution we aim to further facilitate visual analytics on complex data sets for varying data exploration tasks and purposes based on different user characteristics and data use contexts.
01A - Beitrag in wissenschaftlicher Zeitschrift
Open urban and forest datasets from a high-performance mobile mapping backpack. A contribution for advancing the creation of digital city twins
(International Society of Photogrammetry and Remote Sensing, 2021) Blaser, Stefan; Meyer, Jonas; Nebiker, Stephan
With this contribution, we describe and publish two high-quality street-level datasets, captured with a portable high-performance Mobile Mapping System (MMS). The datasets will be freely available for scientific use. Both datasets, from a city centre and a forest represent area-wide street-level reality captures which can be used e.g. for establishing cloud-based frameworks for infrastructure management as well as for smart city and forestry applications. The quality of these data sets has been thoroughly evaluated and demonstrated. For example, georeferencing accuracies in the centimetre range using these datasets in combination with image-based georeferencing have been achieved. Both high-quality multi sensor system street-level datasets are suitable for evaluating and improving methods for multiple tasks related to high-precision 3D reality capture and the creation of digital twins. Potential applications range from localization and georeferencing, dense image matching and 3D reconstruction to combined methods such as simultaneous localization and mapping and structure-from-motion as well as classification and scene interpretation. Our dataset is available online at: https://www.fhnw.ch/habg/bimage-datasets
04B - Beitrag Konferenzschrift
Dynamic patterns of global brain communication differentiate conscious from unconscious patients after severe brain injury
(Frontiers Research Foundation, 2021) Golkowski, Daniel; Willnecker, Rebecca; Rösler, Jennifer; Ranft, Andreas; Schneider, Gerhard; Jordan, Denis; Ilg, Rüdiger
The neurophysiology of the subjective sensation of being conscious is elusive; therefore, it remains controversial how consciousness can be recognized in patients who are not responsive but seemingly awake. During general anesthesia, a model for the transition between consciousness and unconsciousness, specific covariance matrices between the activity of brain regions that we call patterns of global brain communication reliably disappear when people lose consciousness. This functional magnetic imaging study investigates how patterns of global brain communication relate to consciousness and unconsciousness in a heterogeneous sample during general anesthesia and after brain injury. First, we describe specific patterns of global brain communication during wakefulness that disappear during propofol and sevoflurane general anesthesia. Second, we search for these patterns in a cohort of unresponsive wakeful patients and unmatched healthy controls in order to evaluate their potential use in clinical practice. We found that patterns of global brain communication characterized by high covariance in sensory and motor areas or low overall covariance and their dynamic change were strictly associated with intact consciousness in this cohort. In addition, we show that the occurrence of these two patterns is significantly related to activity within the frontoparietal network of the brain, a network known to play a crucial role in conscious perception. We propose that this approach potentially recognizes consciousness in the clinical routine setting.
01A - Beitrag in wissenschaftlicher Zeitschrift
Image-based orientation determination of mobile sensor platforms
(International Society of Photogrammetry and Remote Sensing, 2021) Hasler, Oliver; Nebiker, Stephan
Abstract. Estimating the pose of a mobile robotic platform is a challenging task, especially when the pose needs to be estimated in a global or local reference frame and when the estimation has to be performed while the platform is moving. While the position of a platform can be measured directly via modern tachymetry or with the help of a global positioning service GNSS, the absolute platform orientation is harder to derive. Most often, only the relative orientation is estimated with the help of a sensor mounted on the robotic platform such as an IMU, with one or multiple cameras, with a laser scanner or with a combination of any of those. Then, a sensor fusion of the relative orientation and the absolute position is performed. In this work, an additional approach is presented: first, an image-based relative pose estimation with frames from a panoramic camera using a state-of-the-art visual odometry implementation is performed. Secondly, the position of the platform in a reference system is estimated using motorized tachymetry. Lastly, the absolute orientation is calculated using a visual marker, which is placed in the space, where the robotic platform is moving. The marker can be detected in the camera frame and since the position of this marker is known in the reference system, the absolute pose can be estimated. To improve the absolute pose estimation, a sensor fusion is conducted. Results with a Lego model train as a mobile platform show, that the trajectory of the absolute pose calculated independently with four different markers have a deviation < 0.66 degrees 50% of the time and that the average difference is < 1.17 degrees. The implementation is based on the popular Robotic Operating System ROS.
04B - Beitrag Konferenzschrift
Image-based reality-capturing and 3D modelling for the creation of VR cycling simulations
(Copernicus, 2021) Wahbeh, Wissam; Ammann, Manuela; Nebiker, Stephan; van Eggermond, Michael; Erath, Alexander
With this paper, we present a novel approach for efficiently creating reality-based, high-fidelity urban 3D models for interactive VR cycling simulations. The foundation of these 3D models is accurately georeferenced street-level imagery, which can be captured using vehicle-based or portable mapping platforms. Depending on the desired type of urban model, the street-level imagery is either used for semi-automatically texturing an existing city model or for automatically creating textured 3D meshes from multi-view reconstructions using commercial off-the-shelf software. The resulting textured urban 3D model is then integrated with a real-time traffic simulation solution to create a VR framework based on the Unity game engine. Subsequently, the resulting urban scenes and different planning scenarios can be explored on a physical cycling simulator using a VR helmet or viewed as a 360-degree or conventional video. In addition, the VR environment can be used for augmented reality applications, e.g., mobile augmented reality maps. We apply this framework to a case study in the city of Berne to illustrate design variants of new cycling infrastructure at a major traffic junction to collect feedback from practitioners about the potential for practical applications in planning processes.
01A - Beitrag in wissenschaftlicher Zeitschrift
Criticality creates a functional platform for network transitions between internal and external processing modes in the human brain
(Frontiers Research Foundation, 2021) Kim, Minkyung; Kim, Hyoungkyu; Huang, Zirui; Mashour, George A.; Jordan, Denis; Ilg, Rüdiger; Lee, UnCheol
Continuous switching between internal and external modes in the brain appears important for generating models of the self and the world. However, how the brain transitions between these two modes remains unknown. We propose that a large synchronization fluctuation of brain networks, emerging only near criticality (i.e., a balanced state between order and disorder), spontaneously creates temporal windows with distinct preferences for integrating the network’s internal information or for processing external stimuli. Using a computational model, electroencephalography (EEG) analysis, and functional magnetic resonance imaging (fMRI) analysis during alterations of consciousness in humans, we report that synchronized and incoherent networks, respectively, bias toward internal and external information with specific network configurations. In the brain network model and EEG-based network, the network preferences are the most prominent at criticality and in conscious states associated with the bandwidth 4−12 Hz, with alternating functional network configurations. However, these network configurations are selectively disrupted in different states of consciousness such as general anesthesia, psychedelic states, minimally conscious states, and unresponsive wakefulness syndrome. The network preference for internal information integration is only significant in conscious states and psychedelic states, but not in other unconscious states, suggesting the importance of internal information integration in maintaining consciousness. The fMRI co-activation pattern analysis shows that functional networks that are sensitive to external stimuli–such as default mode, dorsal attentional, and frontoparietal networks–are activated in incoherent states, while insensitive networks, such as global activation and deactivation networks, are dominated in highly synchronized states. We suggest that criticality produces a functional platform for the brain’s capability for continuous switching between two modes, which is crucial for the emergence of consciousness.
01A - Beitrag in wissenschaftlicher Zeitschrift
Outdoor mobile mapping and AI-based 3D object detection with low-cost RGB-D cameras. The use case of on-street parking statistics
(MDPI, 2021) Nebiker, Stephan; Meyer, Jonas; Blaser, Stefan; Ammann, Manuela; Rhyner, Severin Eric
A successful application of low-cost 3D cameras in combination with artificial intelligence (AI)-based 3D object detection algorithms to outdoor mobile mapping would offer great potential for numerous mapping, asset inventory, and change detection tasks in the context of smart cities. This paper presents a mobile mapping system mounted on an electric tricycle and a procedure for creating on-street parking statistics, which allow government agencies and policy makers to verify and adjust parking policies in different city districts. Our method combines georeferenced red-green-blue-depth (RGB-D) imagery from two low-cost 3D cameras with state-of-the-art 3D object detection algorithms for extracting and mapping parked vehicles. Our investigations demonstrate the suitability of the latest generation of low-cost 3D cameras for real-world outdoor applications with respect to supported ranges, depth measurement accuracy, and robustness under varying lighting conditions. In an evaluation of suitable algorithms for detecting vehicles in the noisy and often incomplete 3D point clouds from RGB-D cameras, the 3D object detection network PointRCNN, which extends region-based convolutional neural networks (R-CNNs) to 3D point clouds, clearly outperformed all other candidates. The results of a mapping mission with 313 parking spaces show that our method is capable of reliably detecting parked cars with a precision of 100% and a recall of 97%. It can be applied to unslotted and slotted parking and different parking types including parallel, perpendicular, and angle parking.
01A - Beitrag in wissenschaftlicher Zeitschrift
Criticality creates a functional platform for network transitions between internal and external processing modes in the human brain
(Frontiers Research Foundation, 2021) Kim, Minkyung; Kim, Hyoungkyu; Huang, Zirui; Mashour, George A.; Jordan, Denis; Ilg, Rüdiger; Lee, UnCheol
Continuous switching between internal and external modes in the brain appears important for generating models of the self and the world. However, how the brain transitions between these two modes remains unknown. We propose that a large synchronization fluctuation of brain networks, emerging only near criticality (i.e., a balanced state between order and disorder), spontaneously creates temporal windows with distinct preferences for integrating the network’s internal information or for processing external stimuli. Using a computational model, electroencephalography (EEG) analysis, and functional magnetic resonance imaging (fMRI) analysis during alterations of consciousness in humans, we report that synchronized and incoherent networks, respectively, bias toward internal and external information with specific network configurations. In the brain network model and EEG-based network, the network preferences are the most prominent at criticality and in conscious states associated with the bandwidth 4−12 Hz, with alternating functional network configurations. However, these network configurations are selectively disrupted in different states of consciousness such as general anesthesia, psychedelic states, minimally conscious states, and unresponsive wakefulness syndrome. The network preference for internal information integration is only significant in conscious states and psychedelic states, but not in other unconscious states, suggesting the importance of internal information integration in maintaining consciousness. The fMRI co-activation pattern analysis shows that functional networks that are sensitive to external stimuli–such as default mode, dorsal attentional, and frontoparietal networks–are activated in incoherent states, while insensitive networks, such as global activation and deactivation networks, are dominated in highly synchronized states. We suggest that criticality produces a functional platform for the brain’s capability for continuous switching between two modes, which is crucial for the emergence of consciousness.
01A - Beitrag in wissenschaftlicher Zeitschrift
Gaining overview with transient focus+context maps
(Taylor & Francis, 2021) Hollenstein, Daria; Bleisch, Susanne
Gaining an overview of large spatial data sets presents a challenge common to various domains. 'Overviewing' spatial data involves viewing different areas of focus and context at different scales and requires access to detail from zoomed-out views. Standard pan and zoom interfaces provide limited support with this. Motivated by the application scenario of flood risk monitoring, we extend pan and zoom affordances with a combination of focus+context techniques and multiple maps to support 'overviewing' spatial data with a graph-like information structure. A combination of transient overlays to preview context-on-demand as well as detail-on-demand with the option to decouple additional maps enables fast navigation through the graph-like information space. User-created and -positioned, resizable multiple maps allow for simultaneous exploration of distant regions at flexible scales. The seamless integration of these concepts and the versatility of its components allow for continuously adaptable, user-defined layouts that support various analysis situations. We present a prototype implementation of this interaction model and illustrate its working in application to a hydrometric network, but we believe the model could be transferred to graph-like data in other domains.
01A - Beitrag in wissenschaftlicher Zeitschrift
Map-based assessment of older adults’ life space. Validity and reliability
(BioMed Central, 28.11.2020) Hinrichs, Timo; Zanda, Adriana; Fillekes, Michelle P.; Bereuter, Pia; Portegijs, Erja; Rantanen, Taina; Schmidt-Trucksäss, Arno; Zeller, Andreas W.; Weibel, Robert
Background Map-based tools have recently found their way into health-related research. They can potentially be used to quantify older adults’ life-space. This study aimed to evaluate the validity (vs. GPS) and the test-retest reliability of a map-based life-space assessment (MBA). Methods Life-space of one full week was assessed by GPS and by MBA. MBA was repeated after approximately 3 weeks. Distance-related (mean and maximum distance from home) and area-related (convex hull, standard deviational ellipse) life-space indicators were calculated. Intraclass correlations (MBA vs. GPS and test-retest) were calculated in addition to Bland-Altman analyses (MBA vs. GPS). Results Fifty-eight older adults (mean age 74, standard deviation 5.5 years; 39.7% women) participated in the study. Bland-Altman analyses showed the highest agreement between methods for the maximum distance from home. Intraclass correlation coefficients ranged between 0.19 (95% confidence interval 0 to 0.47) for convex hull and 0.72 (95% confidence interval 0.52 to 0.84) for maximum distance from home. Intraclass correlation coefficients for test-retest reliability ranged between 0.04 (95% confidence interval 0 to 0.30) for convex hull and 0.43 (95% confidence interval 0.19 to 0.62) for mean distance from home. Conclusions While acceptable validity and reliability were found for the distance-related life-space parameters, MBA cannot be recommended for the assessment of area-related life-space parameters.
01A - Beitrag in wissenschaftlicher Zeitschrift