The Cloud model can combine randomicity with ambiguity, and realize the transform between quality and quantity. This paper analyzed the Cloud model, focused on the normal Cloud and its digital characters, provided a method for evaluating system effectiveness based on Cloud model, implementing the transform between qualitative evaluation and quantitative numerical value. Meanwhile the evaluating target system of airborne EW system be constructed and applied this method to evaluate EW system.

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The conventional method of principal component analysis (PCA) is reducing data dimensions directly from m to k (k

Electron beam welding (EBW) with multiple beams is a new technology simultaneous with preheating or postheating, which contributes to reducing residual stresses. To improve corrosion resistance in marine, EBW with multiple beams is employed on AF1410 steel. The weld is uniform, with a width of 7.3-8.4 mm, which is wider than that of conventional welding. To evaluate susceptibility to stress corrosion cracking (SCC), the welding stresses and slow strain rate tests (SSRT) are studied. The longitudinal stresses on the front weld with preheating and postheating are 25% and 15% lower than conventional welding. The transversal stresses also, respectively, decreased by 15% and 6%. The tensile properties of EBW from SSRT present a susceptibility to SCC. Compared with conventional welding, the loss of elongation I δ with preheating and postheating decreases to 0.9-1.5%, and the area reduction rate I R lowers to 7-10%. EBW with multiple beams presents a low susceptibility, attributed to reducing welding stresses related to a temperature gradient.

The magnetocaloric effect (MEC) in Gd 1-x Dy x (x = 0. 13, 0.20, 0.27, 0.34, 0.40) alloys is investigated using commercial elements with purity of up to 99.80% for Gd and Dy. These alloys are prepared by arc melting in stoichiometric proportions on a water-cooled copper crucible under high pure argon atmosphere. As a result, when x was changed from 0 to 40at%, the adiabatic temperature change (∆T ) increases from 1.6 K to 3.1 K, the Curie temperature decreased from 288 K to 245.5 K. Gy 73 Dy 27 exhibits the largest ∆T max value of 3.1 K at the T C value of 260 K among the alloys investigated up to 1.2 T (tesla) applied field, it is almost same as the ∆T of high pure unitary Gd (99.99%) and is clearly superior to commercial unitary Gd (99.80%). The T C of Gy 73 Dy 27 alloy is minor to high pure unitary Gd (99.99%) and commercially unitary Gd (99.80%). But this alloy prepared by commercial elements with low cost has better MEC to be a promising candidate for magnetic working substances for room temperature magnetic refrigeration.