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In dieser Datensammlung befindet sich der digitale Anhang zur Dissertation "Grundlagen für Erholungsplanung in der Stadt. Eine empirische Untersuchung zu Nutzungsmustern ausgewählter öffentlicher Parkanlagen in Dresden." (Seidler 2016). Dieser umfasst einen Kartenteil und ergänzende Anhänge, beispielsweise Grafiken, Fotodokumentationen, Zählbögen, Dokumentationen zur Wegelängenermittlung in den untersuchten Anlagen und zur Dichteermittlungen in den umgebenden Stadtbereichen beispielsweise.
Humans adaptively integrate forward planning and heuristic preferences during goal pursuit
In this paper an automatic approach is proposed to measure flow velocity with an uncooled thermal camera. Hot water is used as thermal tracer. The introduced tracking algorithm utilizes the pyramidal Lucas-Kanade method and is especially suitable for thermal image data. The performance of the new tool is compared to traditional image-based tracking tools, i.e. PIVlab and PTVlab. Experiments are performed in the laboratory for three different flow velocities. Afterwards, tests are conducted in a small stream to illustrate the suitability of the tool for field measurements. Results of the laboratory experiments as well as of the field experiments show that our tracking algorithm, applied to imagery from a thermal camera, outperforms commonly used tracking methods. Our tool provides velocity fields with very high resolution and is in close agreement with reference measurements, whereas PTVlab and PIVlab tend to overestimate and underestimate flow velocities, respectively.
Sicherheitslebenszyklusmodelle beschreiben Tätigkeiten sowie Vorgehensweisen zur Entwicklung und Betrieb von sicherheitstechnischen Geräten bzw. Systemen zur Vermeidung systematischer Fehler. In der vorliegenden Veröffentlichung beschreibt die Entwicklung und Evaluation von Sicherheitslebenszyklusmodelle für Prozessmodule sowie modulare Anlagen. Die Entwicklung basiert auf einer Dokumentenanalyse der Normenserien DIN EN 61508 und DIN EN 61511. Die Evaluation wurde im Rahmen mehrerer Expertenworkshops durchgeführt.
Experimental data for all 35 subjects of the experiment.
An automatic workflow is introduced, including an image-based tracking tool, to measure surface flow velocities in rivers. The method is based on PTV and comprises an automatic definition of the search area for particles to track. Tracking is performed in the original images. Only the final tracks are geo-referenced, intersecting the image observations with water surface in object space. Detected particles and corresponding feature tracks are filtered considering particle and flow characteristics to mitigate the impact of sun glare and outliers. The method can be applied to different perspectives, including terrestrial and aerial (i.e. UAV) imagery. To account for camera movements images can be co-registered in an automatic approach. In addition to velocity estimates, discharge is calculated using the surface velocities and wetted cross-section derived from surface models computed with SfM and multi-media photogrammetry. The workflow is tested at two river reaches (paved and natural) in Germany. Reference data is provided by ADCP measurements. At the paved river reach highest deviations of flow velocity and discharge reach 5% and 4%, respectively. At the natural river deviations are larger (26% and 20%, respectively) due to the irregular cross-section shapes hindering accurate contrasting of ADCP- and image-based results. The provided tool enables the measurement of surface flow velocities independently of the perspective from which images are acquired. With the contact-less measurement spatially distributed velocity fields can be estimated and river discharge in previously ungauged and unmeasured regions can be calculated.