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971.
Summary We study the integration theory for general integral metrics when restricted to upper integrals q, finding improvements in the relation between the classes of the q-integrable and the ql-integrable functions. We give new results and notions which lead to the desirable characterizations of q-integrable functions as ql-integrable f with q(|f|) < ∞, and of ql-integrable functions via the integrability of their upper truncations, under natural conditions which are fulfilled in most
finitely additive integration theories. 相似文献
972.
973.
This paper proposes a new method that extends the efficient global optimization to address stochastic black-box systems. The
method is based on a kriging meta-model that provides a global prediction of the objective values and a measure of prediction
uncertainty at every point. The criterion for the infill sample selection is an augmented expected improvement function with
desirable properties for stochastic responses. The method is empirically compared with the revised simplex search, the simultaneous
perturbation stochastic approximation, and the DIRECT methods using six test problems from the literature. An application
case study on an inventory system is also documented. The results suggest that the proposed method has excellent consistency
and efficiency in finding global optimal solutions, and is particularly useful for expensive systems. 相似文献
974.
Adhesion of zein to solid substrates has been studied using surface energy profiles as indices and by adhesion mapping using
atomic force microscopy (AFM). Different plasticizers like glycerol and sorbitol have been used to form mixed films with zein
and properties of these films are studied using surface energy profiles. Comparison of the results from the different mixed
samples with those from the pure zein films showed that force mapping could identify areas rich in protein. The adhesion maps
produced were deconvoluted from sample topography and contrasted with the data obtained from contact angle measurements. A
comparison of the two methods shows that the extent of contact angle hysteresis is indicative of both hydrophobicity of the
surface as well as the force of adhesion. Mechanical properties and microstructure of zein films prepared by casting from
solutions and using Langmuir-Blodgett film technique have been investigated. Pure zein seemed brittle and exhibited an essentially
linear relationship between stress and strain. Films with plasticizer were tougher than these films. In general, mixed films
showed better mechanical properties than pure films and had higher ultimate tensile strength and increased per cent elongation.
Further, the mixed films of zein showed a higher force of adhesion compared to the pure films. 相似文献
975.
N. Ponpandian A. Narayanasamy D. Prabhu K. Ganesan M. Manivel Raja K. Chattopadhyay 《Journal of magnetism and magnetic materials》2006
The Fe73.5Cu1Nb3Si13.5B9 FINEMET alloy has been prepared by the rapid solidification technique. The critical behaviour of this alloy in the amorphous as well as in its nanocrystalline states has been studied near their respective Curie temperatures. From the values of the critical exponents one can conclude that the alloy behaves like a 3D Heisenberg ferromagnet in the amorphous and nanocrystalline states. But there exists a slight increase in the value of β for the alloy annealed at 823 K (the nanocrystalline state) as observed in most of the amorphous alloys. 相似文献
976.
L. T. Ashchepkov D. V. Davydov 《Computational Mathematics and Mathematical Physics》2006,46(11):1910-1917
Noncooperative games of a finite number of persons with interval-valued payoff functions are considered. The concept of an equilibrium situation is introduced. A reduction of such games to deterministic noncooperative games is proposed. Properties of the reduced games are discussed. Interval antagonistic and bimatrix games are examined, and illustrative examples are considered. 相似文献
977.
A new theory of transverse susceptibility (TS) based on magnetization vector dynamics, as described by the Landau–Lifshitz equation of motion, is given. It is shown that the traditional TS experiment is, in fact, the zero-frequency limit of the ferromagnetic resonance (FMR). The importance of these results resides in the generality of the approach which allows one to find the TS for virtually any magnetic system if an expression for the magnetic free-energy density is known. Moreover, the effect of the frequency of excitatory AC field on the TS experiments and the effect of energy dissipation through the imaginary part of TS emerge coherently from the new TS model. 相似文献
978.
979.
Reductions in overshoot following intense sound exposures 总被引:1,自引:0,他引:1
Overshoot refers to the poorer detectability of brief signals presented soon after the onset of a masking noise compared to those presented after longer delays. In the present experiment, brief tonal signals were presented 2 or 190 ms following the onset of a broadband masker that was 200 ms in duration. These two conditions of signal delay were tested before and after a series of exposures to a tone intense enough to induce temporary threshold shift (TTS). The magnitude of the overshoot was reduced after the exposure when a TTS of at least 10 dB was induced, but not when smaller amounts of TTS were induced. The reduction in overshoot was due to a decrease in the masked thresholds with the 2-ms delay; masked thresholds with the 190-ms delay were not different pre- and post-exposure. The implication is that the mechanisms responsible for the normal overshoot effect are temporarily inactivated by the same stimulus manipulations that produce a mild exposure-induced hearing loss. Thus the result is the paradox that exposure to intense sounds can produce a loss of signal detectability in certain stimulus conditions and a simultaneous improvement in detectability in other stimulus conditions. 相似文献
980.