Method for analysis and dynamism of factory structure in automotive manufacturing

A turbulent environment characterized by unsteady economic cycles, customized products, a growing bandwidth of products, an exploding number of variants and shorter product life cycles force manufacturers to permanent adaptation of their factories. Flexible and changeable structures will be required to enable factories dealing with the technological challenges and economic pressure of the future competitively. In order to achieve changeability objectives in manufacturing, a detailed analysis of existing structures and its representative attributes is essential. It is the basis for systematic structure planning of factories. In this paper a method for analyzing the capacitive and technological structure of a factory embedded in a network of manufacturing and its network of suppliers is presented. The synchronization of product and production development under the influence of change is intended. Therefore, the structural views of product and production are specifically in focus of the method. Based on the results of the analysis models an approach of a tool for giving product and production structure dynamism is suggested to investigate the effects and dependencies of change drivers in manufacturing.     

Treiber der Adoption SaaS-basierter Anwendungen

Software-as-a-Service (SaaS) is said to become an important cornerstone of the Internet of Services. However, while some market research and IT provider firms fervently support this point of view, others already conjure up the failure of this on-demand sourcing option. Oftentimes based on weak empirical data and shaky reasoning, these inconsistent perspectives lack scientific rigor and neglect to present a more differentiated picture of SaaS-adoption. This study seeks to deepen the understanding of factors driving the adoption of Software-as-a-Service (SaaS). Grounded in transaction cost theory, the resource-based view, and the theory of planned behavior, the authors develop a research model to assess SaaS-adoption at the application level. Survey data of 297 firms in Germany with 374 valid response items across different industries were collected to test the theoretical model. Our analysis revealed that patterns of the decision on SaaS-adoption differ across application types. Social influence, attitude toward SaaS-adoption, adoption uncertainty, and strategic value turned out to be the strongest and most consistent drivers across all application types. Furthermore, it was found that firm size does not matter in SaaS-adoption, since large enterprises and small- and medium-sized companies had similar adoptation rates. Overall, this study provides relevant findings that IT vendors can use to better appeal to potential companies that consider adopting SaaS.     

A modern workflow for force-field development – Bridging quantum mechanics and atomistic computational models

In this article we present our recent efforts in designing a comprehensive consistent scientific workflow, nicknamed Wolf₂ Pack, for force-field optimization in the field of computational chemistry. Atomistic force fields represent a multiscale bridge that connects high-resolution quantum mechanics knowledge to coarser molecular mechanics-based models. Force-field optimization has so far been a time-consuming and error-prone process, and is a topic where the use of a scientific workflow can provide obvious great benefits. As a case study we generate a gas-phase force field for methanol using Wolf₂ Pack, with special attention given toward deriving partial atomic charges.     

Observations of quantized vorticity generated in superfluid 4He flow through 2-Μm-diameter orifices

A beam of charged vortex rings is used to study the vorticity present downstream from an array of 2-m-diameter orifices through which a steady flow of superfluid ⁴He is driven at known velocity and pressure head p. From the measured attentuation of the beam at low p, we infer a density of vortex line less than predicted by the Feynman critical velocity model. Possible explanations are considered. We find evidence that an interconnected tangle of vortices is formed above a certain value of p, which is in reasonable agreement with theory, at least for one orifice plate. Charge transfer and transient attenuation measurements indicate that this tangle decays in part into small vortex rings. These results are compared with an earlier experiment of Gamota.Research supported in part by the National Science Foundation under grant DMR 72-02971.     

Glass-fibre-reinforced composites with enhanced mechanical and electrical properties - Benefits and limitations of a nanoparticle modified matrix

Nanoparticles and especially carbon nanotubes (CNTs) provide a high potential for the modification of polymers. They are very effective fillers regarding mechanical properties, especially toughness. Furthermore, they allow the implication of functional properties, which are connected to their electrical conductivity, into polymeric matrices. In the present paper, different nanoparticles, as fumed silica and carbon black, were used to optimise the epoxy matrix system of a glass-fibre-reinforced composite. Their nanometre-size enables their application as particle-reinforcement in FRPs produced by the resin-transfer-moulding method (RTM), without being filtered by the glass-fibre bundles. Additionally, an electrical field was applied during curing, in order to enhance orientation of the nanofillers in z-direction. The interlaminar shear strengths of the nanoparticle modified composites were significantly improved (+16%) by adding only 0.3 wt.% of CNTs. The interlaminar toughness G_Ic and G_IIc was not affected in a comparable manner. The laminates containing carbon nanotubes exhibited a relatively high electrical conductivity at very low filler contents, which allows the implication of functional properties, such as stress-strain monitoring and damage detection.     

Physical attractiveness and health: Comment on Weeden and Sabini (2005).

Evolutionary behavioral biology suggests that certain characteristics of the human face and body are important for mate preferences and are therefore subject to sexual selection. J. Weeden and J. Sabini (see record 2005-11504-001) identify a number of weaknesses in the association between traits' attractiveness and health. In contrast, the authors argue that (a) studies on preferences for physical characteristics that rely on 1 trait permit only limited interpretation, (b) limitations placed on J. Weeden and J. Sabini's review exclude important associations, (c) there are misconceptions in their treatment of some traits, and (d) their selected literature provides an inaccurate picture regarding effect size. The authors suggest that future research in this field should seek conceptual and methodological constancy in trait selection and in the evaluation of attractiveness- and health-related traits. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the Precision in Estimating the Location of Edges and Corners

Recently, in Rohr [13], we analyzed the systematiclocalization errors introduced by local operators for detectinggrey-value corners. These errors are inherently due to thedifferential structure of the operators and, in general, areenlarged by discretization and noise effects. Here, we take thestatistical point of view to analyze the localization errorscaused by noisy data. We consider a continuous image model thatrepresents the blur as well as noise introduced by an imagingsystem. In general, the systematic intensity variations arenonlinear functions of the location parameters. For this modelwe derive analytic results stating lower bounds for the locationuncertainty of image features. The lower bounds are evaluatedfor explicit edge and corner models. We show that the precisionof localization in general depends on the noise level, on thesize of the observation window, on the width of the intensitytransitions, as well as on other parameters describing thesystematic intensity variations. We also point out that theuncertainty lower bounds in localizing these image features canin principle be attained by fitting parametric models directlyto the image intensities. To give an impression of theachievable accuracy numerical examples are presented.