Cities are complex systems connected to economic, ecological, and demographic conditions and change. They are also characterized by diverging perceptions and interests of citizens and stakeholders. Thus, in the arena of urban planning, we are in need of approaches that are able to cope not only with urban complexity but also allow for participatory and collaborative processes to empower citizens. This to create democratic cities. Connected to the field of smart cities and citizens, we present in this paper, the prototype of an urban digital twin for the 30,000-people town of Herrenberg in Germany. Urban digital twins are sophisticated data models allowing for collaborative processes. The herein presented prototype comprises (1) a 3D model of the built environment, (2) a street network model using the theory and method of space syntax, (3) an urban mobility simulation, (4) a wind flow simulation, and (5) a number of empirical quantitative and qualitative data using volunteered geographic information (VGI). In addition, the urban digital twin was implemented in a visualization platform for virtual reality and was presented to the general public during diverse public participatory processes, as well as in the framework of the "Morgenstadt Werkstatt" (Tomorrow's Cities Workshop). The results of a survey indicated that this method and technology could significantly aid in participatory and collaborative processes. Further understanding of how urban digital twins support urban planners, urban designers, and the general public as a collaboration and communication tool and for decision support allows us to be more intentional when creating smart cities and sustainable cities with the help of digital twins. We conclude the paper with a discussion of the presented results and further research directions.Sustainability 2020, 12, 2307 2 of 17 representations of material or immaterial objects, e.g., machines of the real world. Digital twins enable comprehensive data exchange and can contain models, simulations, and algorithms describing their counterpart, including its features and behavior in the real world [2]. To enhance real-life perception, they can be implemented in virtual reality (VR).To that end, we developed an urban digital twin applied to the town of Herrenberg in Germany, which can be applied and visualized almost seamlessly across all scales, on multiple layers, and in different categories of data in virtual and augmented reality (VR, AR) for collaborative and participatory processes, focusing on urban planning, urban design, and decision support.The Herrenberg digital twin differs from other simulation-based studies in the field of smart cities, in particular by linking and combining various urban data from models, analysis, and simulation and by the implementation of social data collected from citizens. Furthermore, the visualization in virtual reality ("virtual twin") not only enables broad citizen participation but also collaboration between stakeholders. The advantage of using virtual reality environments-s...

PurposeThe purpose of this paper is to present an application of augmented reality (AR) in the context of teaching of electrodynamics. The AR visualization technique is applied to electromagnetic fields. Carrying out of numerical simulations as well as preparation of the AR display is shown. Presented examples demonstrate an application of this technique in teaching of electrodynamics.Design/methodology/approachThe 3D electromagnetic fields are computed with the finite element method (FEM) and visualized with an AR display.FindingsAR is a vivid method for visualization of electromagnetic fields. Students as well as experts can easily connect the characteristics of the fields with the physical object.Research limitations/implicationsThe focus of the presented work has been on an application of AR in a lecture room. Then, easy handling of a presentation among with low‐hardware requirements is important.Practical implicationsThe presented approach is based on low‐hardware requirements. Hence, a presentation of electromagnetic fields with AR in a lecture room can be easily done. AR helps students to understand electromagnetic field theory.Originality/valueWell‐known methods like FEM and AR have been combined to develop a visualization technique for electromagnetic fields, which can be easily applied in a lecture room.

No abstract

Maximum likelihood analysis is a powerful technique for inferring evolutionary histories from genetic sequence data. During the fall of 2003, an international team of computer scientists, biologists, and computer centers created a global grid to analyze the evolution of hexapods (arthropods with six legs). We created a global grid of computers using systems located in eight countries, spread across six continents (every continent but Antarctica). This work was done as part of the SC03 HPC Challenge, and this project was given an HPC Challenge award for the "Most Distributed Application." More importantly, the creation of this computing grid enabled investigation of important questions regarding the evolution of arthropods -research that would not have otherwise been undertaken. Grid computing will thus lead directly to new scientific insights.

No abstract