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Today, system engineering companies face the challenge to align their processes optimally to the project goals to fulfill the project requirements. Process optimization is done on development process models as planning abstraction. This is currently, with the existing process models and process modeling languages, not possible because the languages are not suitable. This work presents a formal, yet flexible process modeling language that can be used to capture development processes on arbitrary abstraction levels. This modeling language is complemented by analysis and synthesis methods and tools to optimize process models appropriately and to bind process and process model tight together.
Unternehmen der Systementwicklung stehen heutzutage vor der Aufgabe ihre Prozesse optimal auf die jeweiligen Projektziele auszurichten, um den Projektanforderungen gerecht zu werden. Die Optimierung der Prozesse geschieht dabei auf den Planungsabstraktionen der Entwicklungsprozesse, der Entwicklungsprozessmodellebene. In dieser Arbeit wird eine formale und gleichzeitig flexible Prozessmodellierungssprache vorgestellt, die in der Lage ist, Entwicklungsprozesse in beliebigen Abstraktionen wider zu spiegeln. Zudem wurden entsprechende Analyse- und Synthesemethoden implementiert, um die Optimierung der Prozessmodelle zu unterstützen und Prozesse und Prozessmodelle eng aneinander zu binden.
The effects of reaction parameters on Hurn:xwiley:23670932:media:cptc202000216:cptc202000216-math-0001 production from ethanol photocatalysis in the gas phase have been investigated. The photocatalytic activity evolves from an early mass‐transfer limited regime to an independent one at later irradiation times, which is interpreted in terms of a photocatalytic site activity distribution. Ethanol molar fraction exhibits two different domains, with Hurn:xwiley:23670932:media:cptc202000216:cptc202000216-math-0002 production increasing up to a molar fraction of 0.12, beyond which it plateaus. Hurn:xwiley:23670932:media:cptc202000216:cptc202000216-math-0003 :AcH ratios are very sensitive to reaction conditions, reaching 1.8 at low reactant flows. UV light is converted to Hurn:x-wiley:23670932:media:cptc202000216:cptc202000216-math-0004 with an efficiency of nearly 3 %.
Social networking technologies such as social media, crowd concepts, or gamification represent key resources for the integration of customers, value network partners, and the community into sustainable business models. However, there is a lack of understanding of how sustainable enterprises apply such technologies. To close this gap, we propose a taxonomy of design options for social networking technologies in sustainable business models. Our taxonomy comprises eight dimensions that deal with relevant questions of the design of social networking technologies. When creating our taxonomy, we built on existing literature and use cases and involved experienced practitioners in the field of sustainable business models for the validation of our taxonomy. In this way, our study contributes to knowledge on the use of social networking technologies in sustainable business models and how such technologies influence the boundaries of sustainable business models. Likewise, we provide practical insights into the use of social networking technologies in sustainable business models.
The simulation of the residual stress field achieved by shot peening cannot be carried out on component-large models. Hence, an efficient unit cell model for the simulation of the shot peening process is developed. The model allows both, the simple inclusion of a pre-stress and the evaluation of the up-arching of the Almen strip. For this purpose, generalized coupling constraints for the periodic boundaries of the unit cell are developed. These allow for displacement and rotation of the coupled boundaries relative to each other. In the coupling constraints, this is accomplished by respective variables, which can either be prescribed to the analysis or read out as a result from the analysis. Hence, the unit cell can expand, shear, bend and twist under driving forces like, e. g., residual stresses or thermal effects. At the same time, deformations of the cell’s periodic boundary pairs are kept congruent by the generalized coupling. The ability to cover expansion is novel regarding known periodic boundary conditions. Also, the application of a generalized unit cell to shot peening is new.
Results obtained with the generalized unit cell are displayed, demonstrating its capabilities: A fundamental analysis of the residual stress field from shot peening shows inhomogeneities at a fatigue relevant level to be inevitable. A validation of the model was done by comparison with experimental Almen strip shot peening tests reported in literature. Shot peening under pre-stress is demonstrated and its results in terms of residual stress are evaluated. The application of the generalized unit cell is not limited to shot peening.
Various overoxidized poly(1H-pyrrole) (PPy), poly(N-methylpyrrole) (PMePy) or poly(3,4-ethylenedioxythiophene) (PEDOT) membranes incorporated into an acrylate-based solid polymer electrolyte matrix (SPE) were directly electrosynthesized by a two-step in situ procedure. The aim was to extend and improve fundamental properties of pure SPE materials. The polymer matrix is based on the cross-linking of glycerol propoxylate (1PO/OH) triacrylate (GPTA) with poly(ethylene glycol) diacrylate (PEGDA) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as a conducting salt. A self-standing and flexible polymer electrolyte film is formed during the UV-induced photopolymerization of the acrylate precursors, followed by an electrochemical polymerization of the conducting polymers to form a 3D-IPN. The electrical conductivity of the conducting polymer is destroyed by electrochemical overoxidation in order to convert the conducting polymer into an ion-exchange membrane by introduction of electron-rich groups onto polymer units. The resulting polymer films were characterized by scanning electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy, differential scanning calorimetry, thermal analysis and infrared spectroscopy. The results of this study show that the combination of a polyacrylate-matrix with ion selective properties of overoxidized CPs leads to new 3D materials with higher ionic conductivity than SPEs and separator or selective ion-exchange membrane properties with good stability by facile fabrication.
The market for external ratings is dominated worldwide as well as in the European Union (EU) by three major credit rating agencies (CRAs). These “Big Three” are Standard & Poor's (S&P), Moody's and Fitch Ratings. Due to the oligopolistic market structure and possible involvement in the 2008 financial crisis, the rating agencies have constantly come under criticism. This was associated with stricter regulatory requirements to ease the situation. The EU-Regulation on credit rating agencies („CRA-Regulation“) coming into force 2009 and its amendments in 2011 and in 2013 have mainly governed such regulation. The aim of the article is to analyse potential regulatory impact on the still inherent oligopolistic situation on the EU rating market in the context of the CRA-Regulation. Selected key figures are used to observe over a defined period of time if and how the dominance has changed. The motivation for this article is the observation, that political and private efforts to establish a European rating agency as a counterweight to the three major agencies and other approaches to increase competition in the rating market, followed, which has not been resounding to date. In summary, it is shown that new agencies have a potential impact on the EU rating market and that the three major rating agencies still dominate the market but within a changed environment.
Vanadium carbide (VC) reinforced FeCrVC hardfacings have become important to improving the lifetime of tools suffering abrasive and impressive loads. This is because the microstructural properties of such hardfacings enable the primary VCs to act as obstacles against the penetrating abrasive. Because dilution is supposed to be the key issue influencing the precipitation behaviour of primary carbides during surfacing, the development of deposit welding processes exhibiting a reduced thermal impact, and hence lower dilution to the base material, is the primary focus of the current research. By inserting an additional hot wire in the melt, an approach was developed to separate the material and energy input during gas metal arc welding (GMAW) and hence realised low dilution claddings. The carbide content could be increased, and a grain refinement was observed compared with conventional GMAW. These effects could be attributed to both the reduced dilution and heterogeneous nucleation.
Aims: This study examines the relationship between the time, students spent abroad, personality traits and circumstances during this time with the student’s intercultural competence and integration performance in the target culture. Design and sample: The study had a correlative cross-sectional design. 202 academic subjects were surveyed. The average age was 22 years. There was one measuring time, to which 58 % of the participants stated that they have had a stay abroad. Measurements: Metacognitive, cognitive, motivational and behavioural intercultural competence were measured with the Cultural Intelligence Scale. The personality traits involvement, discipline, social competence, cooperation, dominance and stability were captured with the "Bochum inventory for job-related personality description-6F". Work-related attitudes as patterns of behaviour and experience were measured using the "Work-related Behaviour and Experiencing Pattern 44" (Geman: Arbeitsbezogene Verhaltens- und Erlebensmuster; AVEM). In addition, the demographic factors and characteristics of stays abroad as well as the integration into the target culture based on the Sociocultural Adaption Scale were examined. The data was tested for relationships and differences by tests for mean differences, variance and regression analyses. Results: There was a positive correlation between duration and cognitive, motivational and behavioural intercultural competence. The motivational competence is higher in subjects who have no risk pattern in the AVEM. The different types of competence influence each other at diverse times. Moreover, the suggested structural equation model could be confirmed. This showed the effect of the AVEM pattern on intercultural competence, moderated by the stay abroad and the social competence.
The central aim of the investigation at hand is to deal with the problem areas of Human Resource Management, which arise by demographic changes and migration. The paper focuses on mutual relationships. Managers and human resource managers are considered as multipliers. Older employees, migrants and women are important potential. Therefore, following research questions have been investigated: Which competences are necessary to promote to recognise the potential of migrants correctly and to promote them? Do the multipliers have to be more sensitized for the issue diversity? Do they have to develop specific competences to make the system more permeable and to make the entry and promotion of migrants possible? Which competences should be promoted to increase the sensitivity for diversity? The questions were examined by a qualitative investigation to develop hypotheses for a quantitative study. Overall, 30 interviews with managers, human resource managers and diversity representatives of the large DAX companies were conducted. Furthermore, 17 employees with immigration background and 15 employees without an immigration background were interviewed. The data was transcribed and analysed by the qualitative content analysis according to Mayring (2010). Comparative analyses were made with single items with Likert Scales. The investigation of managers and employees is a highly diversified issue. Therefore, the main focus of the project lays on the problem areas, conflicts and competences of human resources managers in demographic-sensitive personnel management. In comparison, employees with and without an immigration background were asked. The results show an interesting field of tension between self-perception and perception of others and the assessment of the relevance of diversity attitudes and measures, competences and their implementation. Furthermore, a contrary perception regarding strains and stresses of person with and without immigration background is determined, which is developed in the consequences of migrations stress and experiences of discrimination. The results indicate the need of promotion of competences, especially regarding intercultural competence. A critical analysis of the results will be presented.