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Christopher Alexander publizierte 1977 erste Muster (Patterns) für die Stadt- und Gebäudearchitektur. Mittlerweile sind Muster in der Softwarearchitektur und -entwicklung etabliert und weitverbreitet. Muster beschreiben abstrakte und bewährte Lösungen für wiederkehrende Problemstellungen. Im Fall von Architekturentwürfen von Softwaresystemen, stehen Muster in verschiedenen Beziehungen zueinander. Um dies abbilden zu können, wird ein Entwurfsmodell entwickelt, welches aus Musterinstanzen und ihren Beziehungen besteht. Werden auf diese Weise Softwaresysteme modelliert, so ist oft eine manuelle Umsetzung in eine konkrete Programmiersprache oder Technologie erforderlich. Zur besseren Wiederverwendbarkeit wird ein Konzept vorgestellt um die Verbindung zwischen Muster und Musterimplementierung sowie die Verbindung zwischen den Musterimplementierungen abzubilden. Basierend auf einer benutzerdefinierten Selektion, die eine Abbildung von Musterinstanzen auf Musterimplementierungen darstellt, sollen die Musterimplementierungen automatisiert aggregiert werden. Hierfür werden die Eigenschaften von Musterimplementierungen und Aggregationsoperatoren betrachtet. Insbesondere wird die Eigenschaft berücksichtigt, dass Entwurfsmodelle einem Graphen entsprechen. Daraus wird ein Konzept für die Aggregation entwickelt. Um die Anforderungen zu erarbeiten und abschließend den Prototyp zu validieren, werden drei Referenzszenarien aus den Cloud Computing Patterns und den Enterprise Integration Patterns definiert. Das Konzept wird in einem Prototypen umgesetzt, basierend auf Pattern Atlas. Dazu wird ein Editor für Entwurfsmodelle und Aggregationsoperatoren zur automatisierten Aggregation von Musterimplementierungen implementiert. Dies umfasst eine Implementierung für die Aggregation von Musterimplementierungen zu Amazon Web Services Cloud Formation Templates und Implementierungen für die Aggregation von Apache ActiveMQ Konfigurationen. Anhand des Prototyps wird demonstriert, dass eine automatisierte Aggregation von Musterimplementierungen von Mustern mehrerer Mustersprachen möglich ist., Christopher Alexander published the first patterns for urban and building architecture in 1977. In the meantime, patterns have become established and widespread in software architecture and development. Patterns describe abstract and proven solutions for recurring problems. In the case of architectural designs of software systems, patterns are related to each other in different ways. In order to be able to represent this, a design model is developed, which consists of pattern instances and their relations. When software systems are modeled in this way, a manual conversion into a concrete programming language or technology is often necessary. For better reusability, a concept is presented to map the connection between pattern and concrete solution as well as the connection between concrete solutions. Based on a user-defined selection, which is a mapping from pattern instances to concrete solutions, the concrete solutions are to be aggregated in an automated way. For this purpose, the properties of concrete solutions and aggregation operators are considered. In particular, the fact that design models correspond to a graph is considered. From this, a concept for aggregation is developed. To elaborate the requirements and finally validate the prototype, three reference scenarios from the Cloud Computing Patterns and the Enterprise Integration Patterns are defined. The concept is implemented in a prototype based on Pattern Atlas. For this purpose, a design model editor and aggregation operators for automated aggregation of concrete solutions are implemented. This includes an implementation for aggregating concrete solutions to Amazon Web Services Cloud Formation Templates and implementations for aggregating Apache ActiveMQ configurations. The prototype is used to demonstrate that automated aggregation of concrete solutions of patterns from multiple pattern languages is possible.

Additive Fertigungsverfahren stellen in den letzten Jahren einen Megatrend dar, da sich mit diesen Verfahren endkonturnahe Werkstücke mit hohem Materialausnutzungsgrad herstellen lassen. Die auch als 3D-Druck bekannt gewordenen additiven Fertigungsverfahren sind jedoch nicht auf die Prototypenfertigung aus Kunststoffen begrenzt. Beim selektiven Laserschmelzen werden metallische Werkstoffe im Pulverbettverfahren mittels Laserstrahl aufgeschmolzen und somit schichtweise aufgebaut. Das Verfahren findet bereits in der Luft- und Raumfahrt, der Medizintechnik, aber auch in der Automobilindustrie und im Maschinenbau Anwendung für Prototypen, Einzelanfertigungen oder Kleinstserien. Des Weiteren ermöglicht es auch die Herstellung von Werkstücken mit besonders hoher Komplexität, die mit spanenden Verfahren nicht herstellbar sind, und bietet dadurch neue Gestaltungsmöglichkeiten bei der Konstruktion. Innerhalb des Vortrags werden nach der Vorstellung des Verfahrens verschiedene Methoden zur numerischen Simulation des selektiven Laserschmelzens von Edelstahl (1.4404) am Beispiel der kommerziellen Software Simufact Additive erläutert. Dazu werden der mechanische und thermo-mechanische Lösungsansatz betrachtet sowie die Methode zur Kalibrierung der Simulationen erläutert. Die Erläuterung eines voll transienten thermo-mechanischen Ansatzes erfolgt unter Verwendung der Software MSC Marc. Des Weiteren wird der Einfluss der Orientierung des Werkstücks im Herstellungsprozess auf resultierende Spannungen, Verzug sowie mechanische Eigenschaften analysiert und mit experimentellen Untersuchungen untersetzt.

Soil detritivores such as Collembola impact plant growth, tissue nutrient concentration and gene expression. Using a model system with pedunculate oak (Quercus robur) microcuttings that display a typical endogenous rhythmic growth with alternating shoot (SF) and root flushes (RF), we investigated the transcriptomic response of oak with and without mycorrhiza (Piloderma croceum) to the presence of Collembola (Protaphorura armata), and linked it to changes in resource allocation by pulse labelling the plants with 13C and 15N. Collembola impacted Gene Ontology (GO) terms as well as plant morphology and elemental ratios with the effects varying markedly with developmental phases. During SF Collembola increased GO terms related to primary growth and this was mirrored in increased 13C and 15N excess in aboveground plant compartments. During RF, Collembola increased GO terms related to plant secondary metabolism and physical fortification. Further, Collembola presence resulted in an increase in plant defence-related GO terms suggesting that Collembola in the rhizosphere prime oak shoots against the attack by fungi or herbivores. Notably, the impact of Collembola on growth, resource allocation and oak gene expression was modified by presence of P. croceum. The results indicate that oaks clearly react to the presence of Collembola in the rhizosphere and respond in a complex way by changing the expression of genes of both primary and secondary metabolism, and this resulted in concomitant changes in plant morphology and physiology.

Various ways are sought today to increase mechanical properties of steels while maintaining their good strength and ductility. Besides effective alloying strategies, one method involves preserving a certain amount of retained austenite in a martensitic matrix. The steel which was chosen as an experimental material for this investigation contained 2.5% manganese, 2.09% silicon and 1.34% chromium, with additions of nickel and molybdenum. An actual closed-die forged part was made of this steel. This forged part was fitted with thermocouples attached to its surface and placed in its interior and then treated using the Q&P process. Q&P process is characterized by rapid cooling from a soaking temperature to a quenching temperature, which is between the Ms and the Mf, and subsequent reheating to and holding at a partitioning temperature where retained austenite becomes stable. The quenchant was hot water. Cooling took place in a furnace. Heat treatment profiles were constructed from the thermocouple data and the process was then replicated in a thermomechanical simulator. The specimens obtained in this manner were examined using metallographic techniques. The effects of cooling rate on mechanical properties and the amount of retained austenite were assessed. The resultant ultimate strength was around 2100 MPa. Elongation and the amount of retained austenite were 15% and 17%, respectively. Microstructures and mechanical properties of the specimens were then compared to the real-world forged part in order to establish whether physical simulation could be employed for laboratory-based optimization of heat treatment of forgings.

Table S2: Number of plants pooled for RNA extraction and sequencing, and 13C and 15N analysis of the three treatments: Stage [root (RF) and shoot flush (SF)], Protaphorura [with (+) and without (-)], Piloderma [with (+) and without (-)].

Table S1: GLM table of F- and P-values on the effect of Protaphorura (with and without), Piloderma (with and without) and Stage [root (RF) and shoot flush (SF)], and their interaction on morphology, 13C atom% excess and 15N atom% excess of oak microcuttings. Significant effects are given in bold.

Tento článek zkoumá vliv velikosti původního austenitického zrna během procesu kalení a přerozdělení (Q-P) na finální mechanické vlastnosti Q-P oceli. Rozdíly v rozložení velikosti austenitické zrna mohou způsobit např. nerovnoměrnou rychlost ohřevu polotovarů před kovacím procesem. Za účelem kvantifikování tohoto vlivu bylo na válcových vzorkách z oceli 42SiCr provedeno definované tepelné zpracování na dilatometru. Rozdílná velikost austenitická zrna byla dosažena tepelným zpracováním, které předcházelo vlastnímu Q-P procesu. Výsledné mechanické vlastnosti byly popsány zkouškou tlakem a odpovídající mikrostruktura byla analyzována pomocí skenovacího elektronového mikroskopu (SEM). This paper examines how the initial austenite grain size in quench and partitioning (Q-P) processes influences the final mechanical properties of Q-P steels. Differences in austenite grain size distribution may result, for example, from uneven heating rates of semi-finished products prior to a forging process. In order to quantify this influence, a carefully defined heat treatment of a cylindrical specimen made of the Q-P-capable 42SiCr steel was performed in a dilatometer. Different austenite grain sizes were adjusted by a pre-treatment before the actual Q-P process. The resulting mechanical properties were determined using the upsetting test and the corresponding microstructures were analyzed by scanning electron microscopy (SEM). These investigations show that a larger austenite grain size prior to Q-P processing leads to a slightly lower strength as well as to a coarser martensitic microstructure in the Q-P-treated material.

Additive manufacturing processes have been investigated for some years, and are commonly used industrially in the field of plastics for small- and medium-sized series. The use of metallic deposition material has been intensively studied on the laboratory scale, but the numerical prediction is not yet state of the art. This paper examines numerical approaches for predicting temperature fields, distortions, and mechanical properties using the Finite Element (FE) software MSC Marc. For process mapping, the filler materials G4Si1 (1.5130) for steel, and AZ31 for magnesium, were first characterized in terms of thermo-physical and thermo-mechanical properties with process-relevant cast microstructure. These material parameters are necessary for a detailed thermo-mechanical coupled Finite Element Method (FEM). The focus of the investigations was on the numerical analysis of the influence of the wire feed (2.5&ndash, 5.0 m/min) and the weld path orientation (unidirectional or continuous) on the temperature evolution for multi-layered walls of miscellaneous materials. For the calibration of the numerical model, the real welding experiments were carried out using the gas-metal arc-welding process&mdash, cold metal transfer (CMT) technology. A uniform wall geometry can be produced with a continuous welding path, because a more homogeneous temperature distribution results.