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Quality of Experience in Telemeetings and Videoconferencing: A Comprehensive Survey
No full textTelemeetings such as audiovisual conferences or virtual meetings play an increasingly important role in our professional and private lives. For that reason, system developers and service providers will strive for an optimal experience for the user, while at the same time optimizing technical and financial resources. This leads to the discipline of Quality of Experience (QoE), an active field originating from the telecommunication and multimedia engineering domains, that strives for understanding, measuring, and designing the quality experience with multimedia technology. This paper provides the reader with an entry point to the large and still growing field of QoE of telemeetings, by taking a holistic perspective, considering both technical and non-technical aspects, and by focusing on current and near-future services. Addressing both researchers and practitioners, the paper first provides a comprehensive survey of factors and processes that contribute to the QoE of telemeetings, followed by an overview of relevant state-of-the-art methods for QoE assessment. To embed this knowledge into recent technology developments, the paper continues with an overview of current trends, focusing on the field of eXtended Reality (XR) applications for communication purposes. Given the complexity of telemeeting QoE and the current trends, new challenges for a QoE assessment of telemeetings are identified. To overcome these challenges, the paper presents a novel Profile Template for characterizing telemeetings from the holistic perspective endorsed in this paper
Augmented Reality for Windy Cities: 3D Visualization of Future Wind Nature Analysis in City Planning
No full textEffective government management, convenient public services, and sustainable industrial development are achieved by the thorough utilization and management of green, renewable resources. The research and the study of meteorological data and its effect on devising renewable solutions as a replacement for nonrenewable ones is the motive of researchers and city planners. Sources of energy like wind and solar are free, green, and popularly being integrated into sustainable development and city planning to preserve environmental quality. Sensor networks have become a convenient tool for environmental monitoring. Wind energy generated through the use and maintenance of wind turbines requires knowledge of wind parameters such as speed and direction for proper maintenance. An augmented reality (AR) tool for interactive visualization and exploration of future wind nature analyses for experts is still missing. Existing solutions are limited to graphs, tabular data, two-dimensional space (2D) maps, globe view, and GIS tool designed for the desktop and not adapted with AR for easy, interactive mobile use. This work aims to provide a novel AR-based mobile supported application (App) that serves as a bridge between three-dimensional space (3D) temporal wind dataset visualization and predictive analysis through machine learning (ML). The proposed development is a dynamic application of AR supported with ML. It provides a user interactive designed approach, presenting a multilayered infrastructure process accessed through a mobile AR platform that supports 3D visualization of temporal wind data through future wind analysis. Thus, a novel AR visualization App with the prediction of wind nature using ML algorithms would provide city planners with advanced knowledge of wind conditions and help in easy decision-making with interactive 3D visualization
Simulation and Optimization of Industrial Disassembly Paths using Position Based Dynamics
No full textThe finding of plausible assembly paths of industrial components is a relevant, actual, but not yet fully resolved research topic. For a fast and robust computation of such paths, rigid body sampling-based motion planning is used. To tackle the problem of unavoidable collisions due to overpressure of components or due to flexible fastening elements, the tolerance of minor collisions is necessary. Tolerating minor collisions always means the manipulation of the configuration space or the direct manipulation of objects in the workspace. These actions enable the computation of assembly paths on industrial data, but they affect (explicitly or implicitly) the shape of the objects and thus the physical plausibility of the computed paths. This makes it important to further analyze the assembly paths. In this paper, we propose a postprocessing method for indus-trial assembly paths that is based on Position Based Dynamics (PBD) and is able to simulate and optimize given assembly paths. We use the PBD framework to simulate and measure the object deformation along the assembly path. For the optimization of the path, we compare the deformed object to the original rigid object and we apply small corrections to the path that decrease the overall deformation. We show the effectiveness of our approach on an academic dataset that provides industrial disassembly scenarios
Positionierung von E-Bikes eines Free-Floating E-Bike-Sharing-Systems
No full textIn diesem Beitrag wird die Integration verschiedener Sensoren zur Bestimmung der Position sich bewegender Fahrzeuge vorgestellt. Die ständige Zunahme der Bevölkerung in urbanen Räumen und das damit einhergehende Wachstum des Verkehrsaufkommens führt in Zeiten, in denen die Auswirkungen des Klimawandels immer stärker spürbar werden, dazu, dass die Entwicklung neuer Mobilitätskonzepte als dringend notwendig erachtet wird und den Weg auch auf die Agenda der Politik gefunden hat. Sharing-Systeme mit emissionsfreien Antrieben wie z. B. E-Bikes können hier einen Beitrag leisten, Luftverschmutzung und
Lärm in Städten zu reduzieren und damit die Lebensqualität in urbanen Räumen zu steigern. Bei Sharing-Systemen ohne bestimmte Standorte der E-Bikes, an denen sie abgeholt und zu denen sie wieder zurückgebracht werden, ist eine verlässliche Positionierung der E-Bikes von entscheidender Bedeutung. Effiziente, durchgängige und kostengünstige Methoden die E-Bikes zu lokalisieren werden benötigt, sowohl um Kunden korrekte Positionen verfügbarer E-Bikes anzuzeigen und bei einer Fahrt verlässlich zu navigieren, als auch für die Servicemitarbeiter des Sharing-Anbieters. In den meisten Fällen genügt die Genauigkeit
einer einfachen Positionierung mittels GNSS. Gerade in urbanen Umgebungen kommt es jedoch öfter zu Ungenauigkeiten aufgrund von Mehrwegausbreitung, Signalbeugung und Abschattung der Satellitensignale. Dies kann bis zum zeitlich begrenzten Ausfall der Positionierung führen. Verschiedene Low-Cost-Sensoren kommen hier in Frage, um eine Trajektorie der gefahrenen Strecke aufzuzeichnen, die ein E-Bike, ab dem Zeitpunkt, ab dem die GNSS-Position nicht mehr verlässlich genug ist, zurückgelegt hat. Um einen zeitlich begrenz-
ten Ausfall von GNSS zu kompensieren wird die Methode der Koppelnavigation (engl.: Dead Reckoning) auf der Basis von zusätzlichen Sensoren wie Gyroskope und Beschleunigungssensoren angewendet. In früheren Untersuchungen mit einem Car-Sharing-System wurden hier schon Erfolge erzielt, allerdings lassen
sich dort durch unterschiedliche Geschwindigkeiten der Räder der Hinterachse Kurvenradien berechnen sowie durch die 42 Sensorimpulse bei einer kompletten Radumdrehung auch wesentlich genauere gefahrene Strecken ermitteln als bei einem E-Bike mit nur einem Sensorimpuls pro Radumdrehung
Evaluation of Geomagnetic Matching Algorithms for Indoor Positioning
No full textGeomagnetic fingerprinting is a promising technology for supplying smartphone indoor navigation algorithms with infrastructureless and to some extent stable local position information. Geomagnetic disturbances in buildings impose a characteristic magnetic signature which can be detected by the phones magnetic sensor. A common approach is to create a database by recording reference fingerprints for example along a predefined known path. In the positioning phase, magnetic data is recorded along a certain time- or path length of the unknown path. The live data can be analyzed and compared against
the prerecorded reference fingerprints. This magnetic matching procedure differs considerably from WiFi fingerprinting, where WiFi data from discrete points is compared. The main difference is that the
described approach uses data recorded as time series. The matching has to consider not only the signal amplitude but also temporal- or spatial matching. In this paper several magnetic matching algorithms are evaluated for usage in an indoor positioning system. A public database is used as data source allowing comparison of the results with other works
Bottom-up assessment of local agriculture, forestry and urban waste potentials towards energy autonomy of isolated regions: Example of Réunion
No full textThis work assesses the role of biomass and municipal solid waste in isolated energy systems. For this, La Réunion, a French overseas territory in the Indian Ocean with a population of about 850,000, serves as a case study. Methodically, the study assesses technical biomass-based potentials based on an island-wide digital landscape model, detailed information on land use, soil, and climate, and a dynamic yield simulation tool, while technical waste-based energy potentials are calculated from local data. In total, 9 crops, 11 waste streams, and forested areas are considered. The potential contribution of biomass and waste to the energy system is studied in three scenarios. In all, unsustainable outcomes are avoided by valorizing only crop residues and applying sustainable harvesting rates to forests. Depending on the scenario, biomass or waste based energy could cover between 19% and 22% of 2019 electricity demand compared to an actual value of 6% (2019). Furthermore, prioritizing the production of secondary energy carriers allows to meet 8% of 2019 energy demand in the transport sector. These results are in good accordance with previous studies and scenarios on Réunion's energy transition. Given its bottom-up approach based on standard geoinformatic data, the proposed method is in principle transferable to other isolated regions, also in developing countries. A first, high-level assessment of four comparable island (states) shows that in three cases similar contributions of biomass and waste as in Réunion can be expected. As a next step, the purely technical assessment shall be complemented by economic considerations
Outdoor Mobile Augmented Reality in Urban Planning; Concepts of Visualizing Focus and Context Using Grayscale Filter in Video-based AR
Get PDFUrban planners and designers often use grayscale masking filters to highlight a selected urban feature and its context without the overwhelming information. With the rising interest in applying augmented reality (AR) technology into the field of urban planning for increasing social engagement, this thesis aims to develop an outdoor mobile AR application that visualizes the urban environment using the mentioned grayscale masking filters. The application is able to apply the grayscale masking filter to the designated buildings in Nordbahnhof, Stuttgart when the device's camera is pointing to them. State of the art of outdoor mobile AR technologies are studied and reviewed. This thesis proposes the concepts and methodology of the video-based AR visualization and the development of the app. The implementation of the concepts and methodology is documented and the implementation process and result are evaluated
Kompakte Hofhäuser - Anleitung zu einem urbanen Gebäudetyp
No full textDer jahrtausendealte Gebäudetyp des Hofhauses wird als Baustein für urbane Quartiere hoher Dichte und Heterogenität neu interpretiert. Das kompakte Hofhaus mit in der Regel drei geschlossenen Aussenwänden hat dabei einen sehr geringen Grundflächenbedarf. Mit drei bis fünf Geschossen und bis zu vier Wohneinheiten kann es Einfamilienhäuser und auch konventionelle Wohngebäude ersetzen. Aussenraum, den übliche Gebäude als Abstand zueinander benötigen, wird als hochwertiger, nicht einsehbarer Hofraum in die kompakten Hofhäuser integriert. Innen- und Aussenräume können so zu einem Raumkontinuum mit hohem Nutzwert verschmelzen.
Jede Wohnung verfügt über mindestens einen solchen Innenhof, der so privat wie ein Badezimmer ist. Das Dilemma konventioneller Bauformen – Dichte = Verlust von Privatsphäre und Stress durch ungewollte Einblicke – wird aufgelöst.
Im Buch werden verschiedene Typen und Varianten für Grundstücke unterschiedlicher Grösse und Proportion detailliert vorgestellt. Sie alle lassen sich problemlos zu urbanen Ensembles und Quartieren kombinieren. Dabei kann jedes Gebäude auf seinem eigenen Grundstück mit einfachen Besitzverhältnissen weitgehend autonom bleiben.
Es gibt viele Möglichkeiten des Einsatzes im urbanen Umfeld bei entsprechend geringem Flächenverbrauch: Nachverdichtung bestehender Wohngebiete, Konversion von Brach- und Restflächen, Neubau von Miniquartieren bis hin zu grösseren Stadtquartieren.
Das Buch zeigt die Merkmale und umfangreichen Typologien zum kompakten Hofhaus auf und gibt damit dem Planer konkrete Hinweise und Kenndaten für seine Arbeit an die Hand
Compact Courtyard Housing - A Guide to an Urban Building Type
No full textThe courtyard house, a type of building that harks back thousands of years, is being reinterpreted as a module for high-density, heterogeneous urban districts. The Compact Courtyard House, generally with three closed exterior walls, takes up only very little space. With three to five storeys and up to four dwelling units, it can replace detached houses and even conventional residential buildings. The outside space that ordinary buildings need as spacing between each other is incorporated into Compact Courtyard Houses as high-quality courtyard space protected from outside viewing. Interior and exterior spaces can thus merge into a single spatial continuum with great utility value.
Each flat has at least one such courtyard, as private as a bathroom. This resolves the dilemma of conventional types of construction in which density equals loss of privacy and stress caused by unwanted visibility.
Going into great detail, the books presents different types and variations for sites of different sizes and proportions. All can be readily combined to create urban ensembles and districts. Nevertheless, each building can remain largely autonomous on its own plot, thus ensuring a simple situation in terms of ownership.
There are many possibilities of deploying this kind of building in the urban setting while only taking up little area: redensification of existing residential areas, conversion of brownfield and leftover areas, new construction of mini-quarters and even larger urban districts.
The book demonstrates the characteristics and extensive typologies of the Compact Courtyard House, providing planners with specific information and specifications for their work
CONCEPT AND EVALUATION OF AN URBAN PLATFORM FOR INTERACTIVE VISUAL ANALYTICS
No full textAbstract. Urban platforms are becoming a vital role player in city resources management for achieving the right balance between social and economic services and their impact on the environment. More and more cities are starting to benefit from an urban platform to state the city conditions and re-coin the shape of life depending on data gathered from different city systems. However, urban platforms need further support of data analytics in respect of reaching a smart city platform helping city planners with better decision making. Besides, the majority of operational urban platforms consider 2D data only, missing out on the possible information that could be obtained from 3D city models. This work proposes a concept for an urban platform that supports data manipulation and visualization plus interactive analytic functionalities. As a prototype, an urban platform is implemented for integrating and processing 3D city models and 2D traffic data to derive air pollutants emission rates with analytic visualization, leading urban planning to concentrate on the most affected areas. In addition, interactive features are implemented, including filtering, querying, and classifying data to support the analytic visualization in the developed urban platform