Guide to Quality Control,Second Revised English Edition

We introduce a very general “forward” method of data analysis that starts from a small, robustly chosen subset of the data and shows the effect of adding observations by a forward search. Powerful diagnostic procedures result: The observations are ordered by their agreement with the proposed transformation, masking is overcome, and the inferential effect of each observation is clear. We apply the resulting method to the transformation of both univariate and multivariate data. Other applications of the forward search are mentioned.     

Estimation of fixed-point temperatures - A practical approach

Phase transition temperatures can be used for thermometer calibrations in accordance with the ITS-90. For this the thermometer is inserted into a fixed-point cell filled with a highly pure substance. While the substance is melting or freezing the temperature inside the cell remains almost constant and the thermometer measures a plateau in the temperature curve. From this plateau the phase transition temperature needs to be estimated for the calibration of the thermometer. This can be done using different mathematical methods, taking into account various systematic deviations as well as reproducibilities of the results depending on the chosen method, the fixed-point material’s purity and above all the amount of fixed-point material. Hence this article presents results from measurements in miniature fixed-point cells filled with zinc of various purities. The plateau curves were measured at different heating rates and comparatively analysed using five different estimation methods.     

Theoretical and Experimental Investigation of Gas-Lubricated,Pivoted-Pad Journal Bearings

This paper presents some of the theoretical predictions and experimental results for the steady-state characteristics of a gas-lubricated, pivoted-pad journal bearing of finite length. An analytical expression for the prediction of load-carrying capacity for these bearings is developed from numerical computer solutions. Sample calculations are presented to show how the theoretical data may be utilized in the design of an actual pivoted-pad bearing. Improvements over previous approximate theories are discussed.     

Stabilitätsanalyse eines aufgelassenen Gipsbergbaus – von der geologisch-hydrogeologisch-geotechnischen Datenerfassung zur numerischen 3D-Simulation

The assessment of the stability of underground structures is an interdisciplinary task which consists of geology, hydrogeology, surveying and geotechnical engineering. This paper gives an example of how these disciplines, their methods and the acquisition of data work together to create a complex three-dimensional computer-model of underground structures. It demonstrates, that especially the complex layout of old and “grown” underground structures cannot be represented accurately in two-dimensional analyses or models and provide no realistic results for stability investigations. Related to the stability of underground structures, a non-negligible factor is the influence of water, whether surface, rain or groundwater. The occurring leaching process of gypsum leads to a weakening of the surrounding rock which causes a strength reduction. This softening of the material must be considered in long-term simulations. The presented comprehensive approach tries to provide a possibility to predict the time-dependent occurrence of vulnerabilities in the rock mass and thus gives the possibility to install support measures in an early stage.     

Experimental Investigation of the Flow in a Continuous-Casting Mold under the Influence of a Transverse,Direct Current Magnetic Field

This article describes laboratory experiments aimed at investigations of flow structures and related transport processes in the continuous-casting mold under the influence of an external direct current (DC) magnetic field. The main value of cold metal laboratory experiments consists in the capabilities to obtain quantitative flow measurements with a reasonable spatial and temporal resolution. The experimental results presented here were obtained using a physical model operating with the room-temperature alloy GaInSn. According to the concept of the electromagnetic brake, the impact of a DC magnetic field on the outlet flow from the submerged entry nozzle (SEN) has been studied up to Hartmann numbers of approximately 400. The effect of the magnetic field on the flow structure turned out to be complex. The flow measurements do not manifest a general braking effect, which would be expected as an overall damping of the flow velocity and the related fluctuations all over the mold volume. Variations of the wall conductivity showed a striking impact on the resulting flow structures. The experiments provide a substantial database for the validation of respective numerical simulations.