Effect of Multi-Scale Thermoelectric Magnetic Convection on Solidification Microstructure in Directionally Solidified Al-Si Alloys Under a Transverse Magnetic Field

The influence of a transverse magnetic field (B < 1 T) on the solidification structure in directionally solidified Al-Si alloys was investigated. Experimental results indicate that the magnetic field caused macrosegregation, dendrite refinement, and a decrease in the length of the mushy zone in both Al-7 wt pct Si alloy and Al-7 wt pct Si-1 wt pct Fe alloys. Moreover, the application of the magnetic field is capable of separating the Fe-rich intermetallic phases from Al-7 wt pct Si-1 wt pct Fe alloy. Thermoelectric magnetic convection (TEMC) was numerically simulated during the directional solidification of Al-Si alloys. The results reveal that the TEMC increases to a maximum ( \( u_{\rm{max} } \) ) when the magnetic field reaches a critical magnetic field strength ( \( B_{\rm{max} } \) ), and then decreases as the magnetic field strength increases further. The TEMC exhibits the multi-scales effects: the \( u_{\rm{max} } \) and \( B_{\rm{max} } \) values are different at various scales, with \( u_{\rm{max} } \) decreasing and \( B_{\rm{max} } \) increasing as the scale decreases. The modification of the solidification structure under the magnetic field should be attributed to the TEMC on the sample and dendrite scales.     

Values as determinants of preferences for housing attributes

Preferences for housing attributes have beenstudied from different theoretical perspectivesand with a great variety of methodologicalapproaches. In explaining housing preferencesthe influence of both macro-level andmicro-level factors has been shownextensively. Relatively little attention hasbeen given, though, to motivational micro-levelfactors such as goals and values. In thisarticle micro-level motivational factors arestudied as determinants of stated preferencesfor housing attributes. The relationshipsbetween such motivational factors as values andgoals on the one hand and preferences forhousing attributes on the other are consideredfrom the perspective of means-end theory. Asemi-structured interviewing technique calledladdering is used for the measurement ofmeans-end chains. Some of the results of apilot project in which means-end theory wasapplied to preferences for housing attributeswill be discussed in the sequel.     

FE analyses and tests in support of Wendelstein 7-X trim coil development

The paper presents an overview of the finite element (FE) analyses on the trim coils (TCs) and tests performed at IPP, and focuses on some specific aspects of the TC assembly. Global FE models (GM) of two types of TCs predicted the coil deformations and reaction forces on the supports. Dead weight, temperature rise during operation up to 80 °C, electromagnetic loads of 19 field configurations, and outer vessel (OV) deformations have been taken into account. In addition, local models were created for the critical winding pack (WP) regions as well as for each support clamp, and were analyzed with boundary conditions determined by the GM. The detailed WP sub-models were developed to verify the insulation strength against local stresses. The simulations were supported by various mechanical tests under static and cyclic loads. Aim of these experiments was to determine the time dependent behavior of the silicone rubber pads which are used as interfaces between TC and supports, and to check and optimize the assembly tools as well as procedures for the TCs and their supports.     

Conceptualizing access to and understanding of information

Universal Access in the Information Society - Many citizens face situations where they have difficulty accessing and understanding information, particularly due to insufficient literacy skills....     

A Primal-Dual algorithm for nonnegative N-th order CP tensor decomposition: application to fluorescence spectroscopy data analysis

Multidimensional Systems and Signal Processing - This work concerns the resolution of inverse problems encountered in multidimensional signal processing problems. Here, we address the problem of...