1,721,176 research outputs found
Substructures and fatigue crack growth in HIPing and semi-liquid die casting A356 alloys
No full text
Distributed utility-maximization using a resource pricing power control in uplink DS-CDMA
No full textThis letter considers a distributed utility maximization power control scheme in uplink DS-CDMA systems. Maximizing a utility function is solved by Lagrangian dual decomposition, where the Lagrangian multiplier can be considered as a resource price charging to users. By adjusting the price in a distributed fashion, the proposed algorithm results in a bang-bang type power control, 'maximum power transmission' or 'shutdown'. Numerical result shows that the proposed algorithm achieves around 95% of the optimal utility maximization with a modest computational burden
The influence of Mn and Cr on the tensile properties of A356-0.2OFe alloy
No full textIn the present work, Mn and Cr were added to a commercial A356 (Al-7.0Si-0.38Mg-0.12Ti-0.02Sr in wt.%)-0.20Fe cast alloy to control the crystallization of beta-Al5FeSi. The tensile properties are compared in terms of the way the microstructures changed before and after the addition of 0.20Mn and 0.13Mn-0.13Cr. The addition of 0.20Mn causes the acicular P-Al5FeSi to be replaced by granular or skeletal alpha-Al(Mn,Fe)Si in solidification, and the additions of 0.13Mn-0.13Cr acts as an effective replacing element of beta-Al5FeSi. Moreover, the addition of 0.20Mn functionally improves the strength, and the addition of 0.13Mn-0.13Cr improves the strain as well as the strength compared to a commercial A356 cast alloy. (c) 2005 Elsevier B.V. All rights reserved.This work was supported by the Korea Research Foundation
Grant (KRF-2004-050-D0005)
A study on ray tracing method for CFD simulations of laser keyhole welding: Progressive Search Method
No full text
Effects of Mn on the crystal structure of alpha-Al(Mn,Fe)Si particles in A356 alloys
No full textIn a commercial Al-7.0Si-0.38Mg cast alloy (A356) with 0.20wt% Fe, added Mn modifies acicular beta-Al5FeSi particles to less acicular alpha-Al(Mn,Fe)Si in both crystallization and precipitation conditions. The crystal structure of alpha-Al(Mn,Fe)Si changes from body-centered cubic (bcc)/ simple cubic (sc) to Pm3 structures in response to an increase in the bulk Mn content of the alloy. The alpha-Al(Mn,Fe)Si particles (50-200nm) precipitate during solution treatment and their precipitation temperature is about 485 degrees C in the as-cast condition. (c) 2006 Elsevier B.V. All rights reserved.This work was supported by the Korea materials and components industry agency (inter-research consortium for MCT)
Shape-dependent Adhesion and Friction on Au Nanoparticles Studied using Probing Atomic Force Microscopy
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
- …
