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排序方式: 共有640条查询结果,搜索用时 15 毫秒
71.
关于物质激励与精神激励基础与结合研究 总被引:3,自引:0,他引:3
从激励的心理学理论基础出发进行分析;对需求、动机、行为等及其相互影响在激励实践中的作用进行了总结。精神激励和物质激励是两种主要的激励模式.它们都是从实践中来经过否定之否定而发展起来的.现代激励理论对两种激励基本上接受,但对两种激励的评价及侧重又各有不同.我国现行激励机制存在一些问题,尤以平均主义为甚.精神激励与物质激励的有机结合.是激励模式发展的未来. 相似文献
72.
A structure for a heterologous double-stranded molecule consisting of an oligoribonucleotide and a β-stranded oligopeptide, paired through complementary Watson-Crick-type hydrogen bonding, is proposed. The basis for such complementary pairings between oligoribonucleotides and oligopeptides is the close correspondence of the distances between the side-chains attached to the backbones of the two molecules. Both inter-nucleotide spacing and inter-amino acid side-chain spacing are approximately 3.4 Å. These kinds of interactions may have implications in protein-mediated-RNA splicing. Formation of a heterologous duplex through such a pairing mode could provide a simple coding mechanism for a reciprocal information transfer between oligonucleotides and oligopeptides. Because of its simplicity and versatility, allowing both specific and nonspecific coding, interactions via these kinds of pairing may have been relevant for prebiotic molecular evolution and for generating complex biological molecules. 相似文献
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M D Srinivas 《Pramana》1982,19(2):159-173
This paper is devoted to a study of some of the basic conditions which have to be satisfied by a hidden variable theory in
order that it can reproduce the quantum mechanical probabilities. Of course one such condition, which emerges from the important
theorem of Bell, is that a hidden variable theory has to be non-local. It is shown that a hidden variable theory is also incompatible
with the conventional interpretation of mixed states and the mixing operation in quantum theory. It is therefore concluded
that, apart from being non-local, a hidden variable theory would also necessarily violate the usual assumption of quantum
theory that the density operator provides an adequate characterization of any ensemble of systems, pure or mixed. 相似文献
75.
Hervé Moulin 《Mathematical Social Sciences》1982,3(3):243-257
Strategic decentralization of collective decision-making is considered when the agents' behaviour is non-cooperative. Specifically they use dominant, maximin risk-avert or sophisticated strategies. The existing results applying these equilibrium concepts are reviewed in three familiar economically meaningful contexts: ordinal (as in voting), random (as in bargaining) and quasilinear (as in public goods problems). 相似文献
76.
Yun-Hong Jiao Xiu-Li Wang Yu-Zhong Wang Li Chen Sheng-Mao Mu Fang Li 《Journal of Macromolecular Science: Physics》2013,52(2):351-364
Polypropylene (PP)/ethylene-octene copolymer (POE) blends with 10–50wt% POE composition were prepared using a twin-screw extruder in the melt state. Mechanical properties of PP and PP/POE blends were tested and the effect of POE content on the crystalline morphology and structure, melting and crystallization behavior, compatiblilty, phase morphology, and the interface cohesiveness of the blends were investigated by polarizing optical microscope (POM), wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), and scanning electron microscopy (SEM). The relationship between mechanical properties and microstructure of the PP/POE blends is discussed. The results showed that POE had a dual function of both reinforcing and toughening PP in the range from 10–40wt%, which was attributed to the integrated functions of the degree of crystallinity of the PP phase, phase morphology, and interface cohesiveness of the blend. 相似文献
77.
Shaofan Li 《哲学杂志》2013,93(7):1059-1084
In this work, we study invariant properties of defect potentials that are capable of describing defect motions in a continuum. By formulating two canonical defect theories, a generalized Nye theory and the Kröner–de Wit theory, we have found three defect potentials that are variational, i.e. their associated Euler–Lagrange equations are differential compatibility conditions of the continuum and defects. Consequently, symmetry properties of these variational functionals render several classes of new conservation laws and invariant integrals that are related with continuum compatibility conditions, which are independent of the constitutive relations of the continuum. The contour integral of the corresponding conserved quantity is path-independent, if the domain encompassed by such an integral is specifically defect-free. The invariant integral is applied to study macroscopically brittle fracture, and a multiscale Griffith criterion is proposed, which leads to a rigorous justification of the well-known Griffith–Irwin theory. 相似文献
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