Heterogeneous Compute Clusters and Massive Environmental Simulations Based on the EPIC Model

In recent years, the crop growth modeling community invested immense effort into high resolution global simulations estimating inter alia the impacts of projected climate change. The demand for computing resources in this context is high and expressed in processor core-years per one global simulation, implying several crops, management systems, and a several decades time span for a single climatic scenario. The anticipated need to model a richer set of alternative management options and crop varieties would increase the processing capacity requirements even more, raising the looming issue of computational efficiency. While several publications report on the successful application of the original field-scale crop growth model EPIC (Environmental Policy Integrated Climate) for running on modern supercomputers, the related performance improvement issues and, especially, associated trade-offs have only received, so far, limited coverage. This paper provides a comprehensive view on the principles of the EPIC setup for parallel computations and, for the first time, on those specific to heterogeneous compute clusters that are comprised of desktop computers utilizing their idle time to carry out massive computations. The suggested modification of the core EPIC model allows for a dramatic performance increase (order of magnitude) on a compute cluster that is powered by the open-source high-throughput computing software framework HTCondor.

Physiological Validation of the 360° Panorama in HMD, for Research and Design of Engineering Classrooms

Classroom design has a significant impact on curriculum development and student motivation. To study the impact of classroom space on students, environmental simulations are often. Due to its relative accessibility, the set-up of 360° panoramas formats shown through head-mounted displays (HMD) stands out. However, this set-up does not have a physiological validation (a physical-simulated comparison) for the specific case of educational spaces. A laboratory fieldwork was developed to address this lack. Participants performed tasks in a classroom or in its virtual replica, in a counterbalanced way. The sample was made up of 40 university students. While the participants performed these tasks, their heart rate variability (HRV) and electrodermal activity (EDA) were recorded. Four physiological metrics were extracted from these records, which quantified the participants’ experience in both the virtual and physical classrooms. Complementarily, the sense of presence was quantified, according to the SUS questionnaire. Regarding the level of presence, the average level generated by the virtual simulation of the classroom was relatively high. Regarding the physiological response, no differences were found in any of the metrics studied. In conclusion, this supports the findings obtained through studies that use this set-up and the development of educational applications based on these technologies.

The hestia project: simulations of the Local Group

ABSTRACT We present the hestia simulation suite: High-resolutions Environmental Simulations of The Immediate Area, a set of cosmological simulations of the Local Group. Initial conditions constrained by the observed peculiar velocity of nearby galaxies are employed to accurately simulate the local cosmography. Halo pairs that resemble the Local Group are found in low resolutions constrained, dark matter only simulations, and selected for higher resolution magneto hydrodynamic simulation using the arepo code. Baryonic physics follows the auriga model of galaxy formation. The simulations contain a high-resolution region of 3–5 Mpc in radius from the Local Group mid-point embedded in the correct cosmographic landscape. Within this region, a simulated Local Group consisting of a Milky Way and Andromeda like galaxy forms, whose description is in excellent agreement with observations. The simulated Local Group galaxies resemble the Milky Way and Andromeda in terms of their halo mass, mass ratio, stellar disc mass, morphology separation, relative velocity, rotation curves, bulge-disc morphology, satellite galaxy stellar mass function, satellite radial distribution, and in some cases, the presence of a Magellanic cloud like object. Because these simulations properly model the Local Group in their cosmographic context, they provide a testing ground for questions where environment is thought to play an important role.

Using Environmental Simulations to Test the Release of Hazardous Substances from Polymer-Based Products: Are Realism and Pragmatism Mutually Exclusive Objectives?

The potential release of hazardous substances from polymer-based products is currently in the focus of environmental policy. Environmental simulations are applied to expose such products to selected aging conditions and to investigate release processes. Commonly applied aging exposure types such as solar and UV radiation in combination with water contact, corrosive gases, and soil contact as well as expected general effects on polymers and additional ingredients of polymer-based products are described. The release of substances is based on mass-transfer processes to the material surfaces. Experimental approaches to investigate transport processes that are caused by water contact are presented. For tailoring the tests, relevant aging exposure types and release quantification methods must be combined appropriately. Several studies on the release of hazardous substances such as metals, polyaromatic hydrocarbons, flame retardants, antioxidants, and carbon nanotubes from polymers are summarized exemplarily. Differences between natural and artificial exposure tests are discussed and demonstrated for the release of flame retardants from several polymers and for biocides from paints. Requirements and limitations to apply results from short-term artificial environmental exposure tests to predict long-term environmental behavior of polymers are presented.

Green Across the Board: Board Games as Tools for Dialogue and Simplified Environmental Communication

Background. Board games are a promising, yet rarely used arena for learning about environmental issues. Existing research suggests that they are highly innovative communication tools that make complex sustainability problems more salient and easily understandable. To date, little to no research exists where several environment-themed board games have been compared in a single study. Method. 17 respondents were invited to board game nights where they were tasked to play an environmental board game of their choosing. The respondents were then invited to participate in subsequent focus group interviews about their gameplay experience and learning outcomes. Results. 5 focus group interviews were transcribed and subjected to a qualitative thematic analysis, revealing 2 main themes; the first revolving around board games as simplified environmental simulations and the second revolving around the players’ perceptions of their own impact on the game board. Conclusion. Our results suggest that board games can be highly effective tools in some aspects of environmental communication. Limitations of the study and suggestions for future research are discussed.

City Maker: Reconstruction of Cities from OpenStreetMap Data for Environmental Visualization and Simulations

Recent innovations in 3D processing and availability of geospatial data have contributed largely to more comprehensive solutions to data visualization. As various data formats are utilized to describe the data, a combination of layers from different sources allow us to represent 3D urban areas, contributing to ideas of emergency management and smart cities. This work focuses on 3D urban environment reconstruction using crowdsourced OpenStreetMap data. Once the data are extracted, the visualization pipeline draws features using coloring for added context. Moreover, by structuring the layers and entities through the addition of simulation parameters, the generated environment is made simulation ready for further use. Results show that urban areas can be properly visualized in 3D using OpenStreetMap data given data availability. The simulation-ready environment was tested using hypothetical flooding scenarios, which demonstrated that the added parameters can be utilized in environmental simulations. Furthermore, an efficient restructuring of data was implemented for viewing the city information once the data are parsed.