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Closing the Gap of Creating Design Concepts for DSS by Applying the Situation Awareness Oriented Design Principles
Cognitive Systems Engineering (CSE) provides methods for system design, which base on the analysis of cognitive demands in the work domain. CSE methods are successfully used to design decision support for many domains, but they provide no guidance on how to develop design concepts after cognitive requirements are derived. By means of the Applied Cognitive Work Analysis (ACWA), a CSE methodology for the analysis and design of decision support systems, we show how Situation Awareness Oriented Design (SAOD) principles could support the definition of requirements for design. We applied the methodology to develop mobile systems for the support of fire brigade team leaders on board a vessel. The results show that using the guidance in form of SAOD principles can enrich the design process compared to the application of ACWA without this guidance
Area scanning method for 3D surface profilometry based on an adaptive confocal microscope
Conventional confocal 3D microscopes suffer from a slow measurement speed due to its requirement of scanning in three directions. Although lateral slit scanning has been proven to perform similarly to single point scanning, a direct area confocal scanning microscope is commonly considered impossible as the system is reduced into a wide-field microscope and loses its depth discerning capability. In this article, a direct area scanning method is proposed for 3D surface profilometry based on a tilted focal field. To demonstrate the underlying principle, theoretical analysis is conducted with simulation result, showing that depth discerning capability can be maintained in area scanning when the tilting angle is specifically chosen according to the numerical aperture of the system. An adaptive experimental setup is constructed based on a programmable light source and a programmable array microscope with chromatic axial encoding. Measurement result of a test target using the proposed method is comparable to the result of conventional array scanning. Although the axial uncertainty is increased by a factor of approximately 2.5, the direct area scanning method is more than 300 times faster than the conventional array scanning mode of the same setup
Appearance-driven conversion of polygon soup building models with level of detail control for 3D geospatial applications
In many 3D applications, building models in polygon-soup representation are commonly used for the purposes of visualization, for example, in movies and games. Their appearances are fine, however geometry-wise, they may have limited information of connectivity and may have internal intersections between their parts. Therefore, they are not well-suited to be directly used in 3D geospatial applications, which usually require geometric analysis. For an input building model in polygon-soup representation, we propose a novel appearance-driven approach to interactively convert it to a two-manifold model, which is more well-suited for 3D geospatial applications. In addition, the level of detail (LOD) can be controlled interactively during the conversion. Because a model in polygon-soup representation is not well-suited for geometric analysis, the main idea of the proposed method is extracting the visual appearance of the input building model and utilizing it to facilitate the conversion and LODs generation. The silhouettes are extracted and used to identify the features of the building. After this, according to the locations of these features, horizontal cross-sections are generated. We then connect two adjacent horizontal cross-sections to reconstruct the building. We control the LOD by processing the features on the silhouettes and horizontal cross-sections using a 2D approach. We also propose facilitating the conversion and LOD control by integrating a variety of rasterization methods. The results of our experiments demonstrate the effectiveness of our method
Superpoints in RANSAC planes: A new approach for ground surface extraction exemplified on point classification and context-aware reconstruction
In point clouds obtained from airborne data, the ground points have traditionally been identified as local minima of the altitude. Subsequently, the 2.5D digital terrain models have been computed by approximation of a smooth surfaces from the ground points. But how can we handle purely 3D surfaces of cultural heritage monuments covered by vegetation or Alpine overhangs, where trees are not necessarily growing in bottom-to-top direction? We suggest a new approach based on a combination of superpoints and RANSAC implemented as a filtering procedure, which allows efficient handling of large, challenging point clouds without necessity of training data. If training data is available, covariance-based features, point histogram features, and dataset-dependent features as well as combinations thereof are applied to classify points. Results achieved with a Random Forest classifier and non-local optimization using Markov Random Fields are analyzed for two challenging datasets: an airborne laser scan and a photogrammetrically reconstructed point cloud. As an application, surface reconstruction from the thus cleaned point sets is demonstrated
Expandierte Zellen, Knochenmark, Fettgewebe: Was ist in Deutschland und Österreich erlaubt?
The options for articular cartilage therapy have been enriched in recent years by the use of concentrated bone marrow and adipose tissue aspirates as well as culture-expanded cells. Especially single step procedures with sampling of bone marrow or adipose tissue aspirates with intraoperative fabrication of cell concentrates seem to be attractive and are aggressively advertised by various manufactures as unproblematic point of care (PoC) procedures; however, by the use of such systems the surgeon effectively becomes the manufacturer of a drug within the statutory framework of the German Medicines Act (AMG). It is compulsory to notify the authorities about the usage, who then classify the procedure according to the method of processing (substantial or non-substantial) and application (homologous or nonhomologous). As cell products classified as advanced therapy medicinal products (ATMP), they require permission for sampling and manufacturing, which can only be gained in cooperation with the competent authorities (e.g. Paul Ehrlich Institute, state authorities). In this context the regulatory framework for the application of intraoperatively harvested bone marrow and adipose tissue aspirates as well as expanded cells for the treatment of articular cartilage diseases in Germany and Austria are discussed
Verschleiß der Umformwerkzeuge beim Präzisionsblankpressen von Quarzglas
Die heutigen Innovationen beruhen nicht zuletzt auf komplex geformten hochpräzisen optischen Komponenten. Das Quarzglas gehört dabei zu den wichtigsten Materialien der Optik. Mit dem Präzisionsblankpressen ist eine effiziente Fertigung von innovativen Optiken aus Glas möglich. Der schnelle Verschleiß der Umformwerkzeuge, bedingt durch die hohe Umformtemperatur des Quarzglases, erlaubt momentan kein wirtschaftliches Einsetzen dieser Technologie zum Umformen von Quarzglas. Das primäre Ziel dieser Arbeit war es daher, ein grundlegendes Verständnis über die Verschleißmechanismen von Presswerkzeugen im Prozess des Präzisionsblankpressens von Quarzglas aufzubauen. In dieser Arbeit wurden theoretische und experimentelle Untersuchungen des thermomechanischen und chemischen Verhaltens des Quarzglases und einiger Substratwerkstoffe durchgeführt. Des Weiteren erfolgten experimentelle Untersuchungen zum Verschleißverhalten des Substratwerkstoffs Glaskohlenstoff. Aus den Ergebnissen der Untersuchungen wurde ein Modell zur Beschreibung der Verschleißmechanismen auf Werkzeugen aus Glaskohlenstoff beim Pressen von Quarzglas erstellt. Statische und dynamische Adhäsion werden als Verschleißmechanismen für die Verschleißerscheinung Glasanhaftung identifiziert und ihre Abhängigkeit von den Prozessparametern beschrieben. Des Weiteren wird das Wachstum der Defekte im Pressprozess erörtert. Ebenfalls liefert das Modell eine Erklärung für die unterschiedlichen Defektgrößen in drei Bereichen auf dem Presswerkzeug. Aus den gewonnenen Erkenntnissen werden Empfehlungen zur Reduzierung des Verschleißes abgeleitet
Neueste Entwicklungen im Bereich des Hochleistungslaserstrahl- und Hybridschweißens von hohen Blechdicken
Bislang kommt das Laserstrahlschweißen bzw. Laserhybridschweißen hauptsächlich bei Dickblechen mit einer Wandstärke von bis zu 15 mm zum Einsatz. Für Anwendungen über 20 mm war dieses Verfahren aufgrund einiger Herausforderung bisher nur bedingt realisierbar. Ein von der Bundesanstalt für Materialforschung und -prüfung (BAM) entwickelte elektromagnetische Schmelzbadunterstützung ermöglicht nun ein einlagiges Schweißen von bis zu 30 mm Wandstärke
Development of a test method for transformation of veterinary pharmaceuticals and biocides in anaerobic liquid manure
Background Spreading of manure on agricultural soils represents an important pathway by which veterinary medicinal and biocidal products enter the environment. To assess their environmental impact in the context of authorization processes, experimental testing of transformation of these compounds in manure is considered in regulatory guidance documents. However, there is no standardized experimental test method available so far. To fill this gap, an experimental test method was developed to examine transformation in liquid cattle and pig manure. Results To account for manure specifics and for a possible influence of manure parameters on transformation rates, a comprehensive data acquisition and statistical analysis were performed. To address the variability of liquid manure of different type and origin, 30 manures were sampled and characterized. Thereof, three cattle and three pig manures were selected to perform anaerobic transformation studies with two radiolabeled veterinary medicinal active substances (14C-salicylic acid and 14C-paracetamol) and a confidential radiolabeled “14C-biocide B” serving as test compounds. Spatial and seasonal variability of manure parameters was quantified, and a sampling technique to obtain homogenous manure samples was developed. Transformation studies with six replicates per sampling point were conducted to examine the influence of test setup, of manure storage conditions, and of parameter variations between manure of the same species and of different species on half-lives, formation of extractable and non-extractable residues and mineralization rates. Finally, a test design was established that yields reproducible results for transformation studies in liquid cattle and pig manure under anaerobic conditions. Conclusions Results give a reliable basis for an experimental test method to perform anaerobic transformation studies in liquid cattle and pig manure. The developed test method comprises detailed guidance on selection of sampling date and site, collection from manure tank, storage duration and temperature in the laboratory, duration of manure acclimation period, and the incubation system design. It proved to give reproducible results in a validation ring test performed in a follow-up project and is planned to be submitted as draft test guideline for approval by the OECD
Nachhaltigkeitsbewertung für Kleinwasserkraftwerke in China
In China, there is a large so far untapped hydro energetic potential of decentralized, cluster-controllable and low emission solutions in the form of small hydropower plants. Their use is intended to help to reduce social imbalances. At the same time the utilization of hydropower has a major impact on nature and the landscape and therefore on society. For assessing the systemic impacts of hydropower use in individual sites or hydropower clusters, a multi criteria approach has been compiled. This can better direct planning processes and provide targeted support to administrative approval procedures. The results of the sustainability evaluation can also be a basis to mobilize innovative financial resources