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41.
The general mobility matrix formulation of the problem of multi-point, coupled structures is discussed and some of the disadvantages are emphasized. Two principally different ways of rearranging the general mobility matrix into corresponding effective mobilities, useful for expressing the vibratory power input to the receiving structure, are investigated theoretically. The two concepts of effective mobility, namely effective point mobility in which the points are considered individually with the interaction between the points taken into account and effective overall mobility in which a space averaged point mobility is deduced, have also been verified experimentally. In addition, some useful approximations of these quantities are derived.  相似文献   
42.
We study the strong coupling limit of U(N) or SU(N) gauge theories with fermions on a lattice. The integration over the gauge and fermion degrees of freedom is performed by analytic methods, leading to a partition function in terms of localized meson and baryon fields. A method for deriving a systematic expansion in the inverse of the space-time dimension of the corresponding Green functions is developed. It is applied to the study of spontaneous breakdown of chiral symmetry, which occurs for any U(N) or SU(N) theory with fermions in the fundamental representation. Meson and baryon spectra are then computed, and found to be in close agreement with those obtained by numerical methods at finite coupling. The pion decay constant is estimated.  相似文献   
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We present the chemical and biological synthesis of caged phosphoproteins using the in vitro nonsense codon suppression methodology. Specifically, phosphoamino acid analogues of serine, threonine, and tyrosine with a single photocleavable o-nitrophenylethyl caging group were synthesized as the amino acyl tRNA adducts for insertion into full-length proteins. For this purpose, a novel phosphitylating agent was developed. The successful incorporation of these bulky and charged amino acids into the alpha-subunit of the nicotinic acetyl choline receptor (nAChR) and the vasodilator-stimulated phosphoprotein (VASP) using an in vitro translation system is reported.  相似文献   
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The problem of point excitation at a T-intersection of two perpendicular plates is studied in order to establish expressions for the point mobility. It is found that the theory for point excitation of the free surface of a semi-infinite elastic solid is applicable in the frequency range associated with structure-borne sound transmission. From this theory the mobility for an infinite system is derived. Based on this model and on an experimental investigation an estimation procedure for the point mobility in the finite dimension case is developed. The agreement with measurements performed in situ is quite acceptable. Both the theoretical and the experimental investigations reveal that the real part of this mobility is small, although it is larger in the experimental results. This indicates that other components of excitation are difficult to eliminate and may contribute to the power input in practice. Because of the small real part of the mobility it is advantageous with respect to the reduction of structure-borne sound power transmission to locate the contact points between a source and the receiver at such intersections. Corrections are deduced for the measured magnitude of the mobility for the case when separate force and motion transducers are used.  相似文献   
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We provide a sorting algorithm, Adaptive Heapsort, that optimally adapts to several known, and new, measures of presortedness. The algorithm is motivated by a new measure, called Osc, which intuitively tells the oscillation within the input sequence. We show that Osc generalizes a number of measures appearing in the literature. Moreover, it has an interesting application in the sweepline technique in computational geometry.  相似文献   
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