A Priori Assessment of Customer Costs in Designing the Life Cycle of Complex Products

The basic stages in the life cycle of a batch of complex engineering products are considered: design, production, operation, and disposal. A priori cost assessment for each stage is discussed. The cost aggregation in the consideration of multiple stages is analyzed. Requirements on the assessment are formulated. Methodological and implementation aspects of the assessment tools are outlined. The conclusion is that it is expedient to predict the costs on the basis of mathematical models of the product batch in an operational environment. The integration of multiple cost estimates is addressed.     

Mechanisms of Active Fuzzy Expertise

Consideration was given to the decision making procedures based on the fuzzy messages of experts whose preferences on the set of collective decisions can also be fuzzy.     

Continuous-wave lasing of single-mode metamorphic quantum dot lasers for the 1.5-μm spectral region

Lasers based on InAs/InGaAs quantum dots grown on metamorphic (In,Ga,Al)As layers deposited by MBE on GaAs substrates exhibited emission near 1.5 μm with a differential quantum efficiency of about 50%. The narrow-stripe lasers operate in a single transverse mode and withstand continuous current density above 20 kA cm^?2 without significant degradation. A maximum continuous-wave output power of 220 mW is obtained. Neither current nor beam filamentation was observed up to the highest pumping levels.     

Formation of ordered metal nanowire-inorganic salt composites

A new phenomenon accompanying the electrolysis of salts has been observed, whereby an ordered composite is formed under certain conditions (electrolyte composition, current density). The composite comprises an inorganic salt crystal penetrated by metal nano- and microwires. This phenomenon can serve as a basis for the technology of oriented and ordered nanowire array synthesis.     

Preparation of Nickel, Iron, and Cobalt Nanopowders via Reduction of Salts with Sodium Dissolved in Liquid Ammonia

Nickel, iron, and cobalt powders are prepared via reduction of salts with sodium dissolved in liquid ammonia. The low temperature of the process and the ability of liquid ammonia to stabilize dangling chemical bonds notably reduce the growth rate of metal particles and prevent their aggregation. The magnetic properties of the nanopowders are investigated.     

Fabrication of Strain-Relaxed Si<Subscript>1 − <Emphasis Type="Italic">x</Emphasis></Subscript>Ge<Subscript>x</Subscript>/Si(001) Buffer Layers of Low Surface Roughness

The results are presented of the fabrication of strain-relaxed graded Si_{1 − x} Ge_x/Si(001) buffer layers with a maximum Ge fraction of about 0.25 that have a low density of threading dislocations (<10⁶ cm⁻²) and low surface roughness. The buffer layers are grown by atmospheric-pressure hydride CVD. It is found that chemical mechanical polishing can reduce their surface roughness to a level comparable with that of the original Si(001) substrates. It is shown that the polished buffer layers can serve as substrates for MBE-grown SiGe/Si heterostructures.__________Translated from Mikroelektronika, Vol. 34, No. 4, 2005, pp. 243–250.Original Russian Text Copyright © 2005 by Vostokov, Drozdov, Krasil’nik, Kuznetsov, Novikov, Perevoshchikov, Shaleev.