A short account of the theory of lubrication. IV. Temperature rise and temperature distribution in bearings

The modern understanding of lubrication is based on the equations of the hydrodynamic theory. These equations, as has been seen, describe the performance of a bearing in terms of the actual film viscosity but, of course, this depends on the temperature of the film, which in general is unknown. We have next to consider whether there is any way of calculating or predicting the steady running temperature of a bearing.It is not commonly realized that there is a rational solution for this problem.The solution depends both on the rate of generating heat by friction, and on the rate of heat transfer from the bearing to its surroundings.     

A theory for decoupling lossless coupled tapered lines with applications to directional couplers

A simple theory is presented for decoupling a pair of lossless coupled nonuniform transmission lines (CNUTL), with a common return and supporting TEM waves, into two lossless nonuniform transmission lines (NUTL). This theory is independent of the port terminations, symmetry conditions, etc. The method directly relates the line parameters of the lossless CNUTL's to those of the decoupled lines and vice versa; further, the matrix parameters of the CNUTL's as a four-port are explicitly expressed in terms of those of the decoupled lines as two-ports. This theory is then utilized to study the applications of CNUTL's as directional couplers.It is shown that for CNUTL's to behave as a codirectional coupler, each of the decoupled lines should be a proportional line, while for contradirectional coupler action, the two decoupled lines have to be duals of each other. The coupling response of the codirectional coupler is found to be periodic, while the phase shift between coupled and transmitted signals varies linearly with frequency. The coupling response of various contradirectional couplers with smooth transition at one of the ends, for which the decoupled lines are “basic NUTL's with hyperbolic solutions”, are studied in detail. It is shown that all these couplers have a high-pass response and that the CNUTL's with “hyperbolic cosine squared lines” as decoupled lines have the best response of all the CNUTL's considered.     

On the definition of a tapology in Hilbert spaces with applications to the white noisy theory

In this paper a topology on Hilbert spaces is defined. The continuity of a map with respect to such a topology is equivalent to the uniform S-continuity around the origin, according to the Gross definition. An example of an application, in which the achieved gives a simple tool for providing the existence of stochastic solutions, is reported for a quite general class of non- linear differential equations driven by white noise.     

浅谈衍生金融工具对传统会计理论的影响及解决建议

70年代以来,国际金融市场上出现的衍生金融工具的发展规模和影响不仅引起各国金融机构和监管当局的广泛关注,而且对传统财务会计理论和实务产生强烈的冲击.本文首先介绍了衍生金融工具的特点,阐述了衍生金融工具对传统财务会计理论的影响及解决的建议.