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The study was conducted to assess and substantiate the key systemic problems of the national engineering of different countries in the context of economic globalization. To achieve this goal, the study used the author's method to assess the dependence of mechanical engineering in Ukraine, Poland and Germany on imports of intermediate goods. According to the results, it was determined that in the periods of increasing economic globalization of mechanical engineering in Ukraine, Poland and Germany has undergone systemic destructive changes and is in a threatening state, from the standpoint of economic security. In particular, in Ukrainian and Polish mechanical engineering, the dependence on imports of high-tech intermediate goods is excessively high. In contrast, German engineering, unlike Ukraine's and Poland's, is less dependent on imports of high-tech products, but requires much more resource-intensive intermediate goods. It is analytically substantiated that the identified problems with the import dependence of mechanical engineering in Ukraine, Poland and Germany are the result of irrational, one-sided perception of economic globalization by the main economic entities of these countries. [ABSTRACT FROM AUTHOR]

Abstract: In the fields of mechanical engineering, friction is ubiquitous. It is a fundamental cause of energy loss and wear. Another concern is the occurrence of comfort‐relevant friction induced vibrations. Prominent examples of this are NVH phenomena such as brake squeal, which is being investigated at great expense by the German automotive industry and academia, to determine its causes and potential influencing factors. For this purpose, numerous specialized measurements are performed, and models of varying complexity are used. All of these measurements and models have the common trait that the coefficient of friction (COF), defined as the ratio of the tangential force and normal force, has a decisive influence on the systems' stability. To parameterize the friction coefficient in macroscopic models, measurements must be performed. In this case, often an average value over time and over various loading procedures is used. As the measurements reveal, the coefficient of friction is in reality not constant, but is subject to a high degree of dynamics on various time scales, caused by complex processes in the boundary layer. A treatment of the coefficient of friction as a steady‐state parameter, or even as a constant, is thus a major reduction. The large variability of the coefficient of friction causes a corresponding variance in the stability limits of the models considered. This phenomenon is observed in the real world, where squealing seems to have a non‐deterministic behavior. This suggests uncertainties in the modeling of the friction coefficient. Due to the various types of uncertainty (variability, incompleteness and inaccuracy), the entire problem is a matter of polymorphic uncertainty. This paper focuses on the modeling of the friction coefficient, taking into account the various causes of uncertainty. Selections of raw data obtained at the authors institute throughout many years of research on friction phenomena in brake systems will be evaluated and classified with respect to its uncertainty properties. (© 2017 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Mechanical tunnel drive methods are gaining ever more significance on account of their mechanisation and efficiency. Mechanical boring can achieve particularly high advance rates in combination with segment lining systems. In order to investigate the load bearing capacity and robustness of segments, high-strength and ultra high-strength concrete segments were made by HOCHTIEF as part of the European Integrated Project TUNCONSTRUCT (www.tunconstruct.org), investigated through numerical simulation and in the laboratory, and then load tested at STUVA in Cologne. The results included an increase of load-bearing capacity in bending of up to 20 %. The development of segments made of high-strength concrete does indeed enable higher load bearing capacities, but there are applications under very high overburden and related pressure where this alone is not sufficient. For such cases, a compressible mortar has been developed for the annular gap filling. This has a compression potential of up 50 % and is capable of absorbing deformation of the rock mass and thus reducing the loading of the segment lining. This type of mortar has been successfully used in a large-scale trial in 2009 at the Jenbach Tunnel in the Inn valley, including the manufacture of the mortar on the construction site, the transport chain to the TBM and the injection into the annular gap. Maschinelle Vortriebsverfahren gewinnen durch ihre hohe Mechanisierung und Effizienz weiter an Bedeutung. Besonders in Kombination mit Tübbingauskleidungssystemen können sie hohe Vortriebsleistungen ermöglichen. Um die Steigerung der Tragfähigkeit und Robustheit von Tübbings zu untersuchen, wurden von HOCHTIEF im Rahmen des Europäischen Verbundforschungsprojekts TUNCONSTRUCT (www.tunconstruct.org) Tübbings aus hochfesten und ultrahochfesten Betonen hergestellt, rechnerisch und labortechnisch untersucht und bei der STUVA, Köln, Belastungstests unterzogen. Dabei konnte unter anderem eine Steigerung der Biegetragfähigkeit von bis zu 20 % festgestellt werden. Die Entwicklung von Tübbings aus höherfesten Betonen ermöglicht zwar höhere Tragfähigkeiten, dennoch gibt es bei sehr hohen Überlagerungsdrücken Anwendungsfälle, bei denen dies alleine nicht ausreicht. Für solche Anwendungen wurden komprimierbare Ringspaltmörtel entwickelt, die mit einem Stauchpotenzial von bis zu 50 % in der Lage sind, Gebirgsverformungen aufzunehmen und so die Belastung auf den Tübbingausbau zu vermindern. Ein solcher Mörtel wurde im Jahr 2009 beim Tunnelvortrieb Jenbach im Inntal in einem Großversuch erfolgreich einem Praxistest unterzogen, bei dem der Herstellungsprozess des Mörtels auf der Baustelle, die Transportkette zur TVM und das Einbringen in den Ringspalt erprobt wurden. [ABSTRACT FROM AUTHOR]

Abstract: In order to ensure a stable and reliable operation of municipal MBR plants, an enhanced mechanical pre-treatment of the raw wastewater is essential. Removal of hair, fibrous material and other contraries which can lead to operational problems at the membrane modules is of particular importance. As the number of full scale applications is continuously increasing, now appropriate investigations can be carried out to determine the removal efficiency of different units (screens, sieves) or different combination of units (multi staged system). First results of such investigations on two German MBR plants were already presented [F.-B. Frechen, W. Schier and M. Wett, Water Practice & Technology, Vol. 1, No. 3, IWA Publishing, 2006, doi: 10.2166/WPT.2006057.]. In 2006, DESEE executed further investigations on another three wwtps in The Netherlands, UK and Germany. This paper summarizes the results, thus updates the information available, discusses the present findings and gives an outlook on future developments. [Copyright &y& Elsevier]

Compares the regional network relationships of small and medium-sized enterprises (SME) in the mechanical engineering and related metal manufacturing industries in Japan and Germany. Basic patterns of vertical network relationships in the two countries; Network relationships of different SME in Japan; Discussion of the horizontal relationships between firms in Japan.

The report is based on a study of various CAD systems used in eight different departments of mechanical engineering. The study aims at comparing the application of CAD systems by different stressor variables (design task, design/operational characteristics of the CAD system, environmental variables) and their effect on the strain of the designer measured by psychophysiological and psychophysical data. In both single and multiple experiments, continuous measurements of psychophysiological parameters (strain measurements) can be correlated to different stress situations in the various phases of the design process and/or operation of the CAD system. As a result, different strain reactions are registered depending on the type of CAD system used and on the respective design phases. [ABSTRACT FROM AUTHOR]