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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   
73.
74.
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.
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.
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   
78.
为解决纯电动汽车车身设计中未考虑正面碰撞相容性的问题,利用基于混合元胞自动机的拓扑优化方法对纯电动汽车的头部结构进行优化,得到了满足正面碰撞相容性指标的优化结构,同时通过正交试验对其尺寸参数进行优化,设计出了一种双保险杠式的汽车头部结构,并验证了它的可行性。  相似文献   
79.
介绍了斯特林制冷机驱动控制源的分类,讨论了不同的驱动方式对探测芯片产生的干扰形式,并给出了驱动控制源采取的改进措施.并对驱动控制源与斯特林制冷机联机实验所产生的干扰情况进行了分析,介绍了驱动控制源采取的有效改进措施.  相似文献   
80.
随机耦合模型在高功率微波效应中的应用   总被引:4,自引:2,他引:2       下载免费PDF全文
分析了微波混沌腔体系统中关键部位感应电压的统计问题,介绍了随机耦合模型在高功率微波效应研究中的计算方法和应用,并以计算机机箱为实验系统,开展了电磁波耦合入计算机机箱腔体的电磁干扰问题研究,对其电路板上关键部位感应电压的统计计算和实验结果进行了比较,其结果基本一致。随机耦合模型在波混沌系统中感应电压的统计探讨为高功率微波效应、电磁兼容等研究提供了一种新的思路。  相似文献   
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