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Self-explicated approaches are popular preference measurement approaches for products with many attributes. This article classifies previous self-explicated approaches according to their evaluation types, i.e. trade-off- versus non-trade-off-based, and outlines their advantages and disadvantages. In addition, it proposes a new method, the presorted adaptive self-explicated approach that is based on Netzer and Srinivasan’s (2011) adaptive self-explicated approach and that combines trade-off- and non-trade-off-based evaluation types. Two empirical studies compare this new method with the most popular existing self-explicated approaches, including the adaptive self-explicated approach and paired comparison preference measurement. The new method overcomes the insufficient discrimination between importance weights, as usually found in non-trade-off-based evaluation types; discourages respondents’ simplification strategies, as are frequently encountered in trade-off evaluation types; is easy to implement; and yields high predictive validity compared with other popular self-explicated approaches.  相似文献   
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The PEN collaboration carries out a precision measurement of the ??+ ?? e +?? decay branching ratio at the Paul Scherrer Institute (PSI, Switzerland). A special mini time-projection chamber (mTPC) has been developed for registration of particles in the pion beam. The chamber contains 14 × 10?3 g/cm2 of matter on the particle path. The chamber was successfully used during one-year-long run. Design and characteristics of the mTPC are described.  相似文献   
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Schaaf  Peter  Wagner  Steffen  Carpene  Ettore 《Hyperfine Interactions》2001,136(3-8):445-452

Laser nitriding and laser cementation are investigated by Mössbauer spectroscopy and complementary methods. It is demonstrated how the backscattering versions of Conversion Electron and Conversion X-ray Mössbauer spectroscopy can contribute to the investigation of surface processes, like the laser-induced formation of nitrides and carbides. Additionally, the formation of semiconducting iron disilicide can be achieved by ion-beam mixing and pulsed laser irradiation of Fe/Si bilayers. The results of both processes are compared.

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Nerve gas mimic binding with Rhodamine B ethylenediamine (1) was studied in organic media. Binding of the nerve gas mimic, diethyl chlorophosphate (DCP), with the probe generated a non-fluorescent intermediate and a fluorescent product. Fluorescent and non-fluorescent products generated were identified using mass spectrometry and X-ray crystallography. Time-dependent density functional theory calculations were also used to investigate the electronic structure of the fluorescent probe in the ground and lowest lying π?→?π* singlet excited state. Though good agreement between theory and experiment can be obtained for the intense peak in the experimental spectrum using non-hybrid functionals, care must be taken when modelling these complexes due to the appearance of an n?→?π* transition that is too low in energy and appears to fall in the shoulders of the π?→?π* transitions.

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Titanium substrates were irradiated in pure nitrogen gas by means of a free-electron laser. The treatment resulted in the formation of δ-TiNx coatings, with surface stoichiometry x≈1 and thickness of about 15 μm. Under specific experimental conditions the nitride phase had a remarkable crystallographic texture with the δ-TiNx(200) planes parallel to the irradiated surface, and well aligned dendrites growing normal to the surface. The mechanism of the dendritic alignment and the origin of the texture correlate with the existence of a solidification front starting at the surface, which is very peculiar for laser surface treatments. This phenomenon is explained with the help of numerical simulations. PACS 61.80.Ba; 81.15.Fg; 81.65.Lp  相似文献   
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A universal covering group of SU(p, q) is parametrized and its groups law in this parametrization is established.  相似文献   
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