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841.
842.
843.
This paper analyses the main forms of government intervention used in the UK to protect the national artistic patrimony. It examines the two most common policy measures used in the art market ‐ export regulation and tax incentives ‐ and reports their use over an eight‐year period from 1990 to 1998. It also reviews the UK's collective obligations to patrimony internationally and specifically as a member of the European Union. This is the first time that these related topics have been considered as a whole. 相似文献
844.
This study investigated whether a relationship existed between instructional style and points of emphasis in the training context of the martial art aikido and the perceptions which practitioners of aikido generated for aikido-related concepts. The findings were gathered within and compared across aikido training settings in two cultures — Japan and the United States. Analysis of the quantitative and qualitative data gathered for this investigation revealed several potent differences between the manner in which Japanese and American aikido practitioners represented their understandings of aikido-related concepts. Differences in the manner in which aikido practitioners in Japan and the United States represented their understandings of aikido reflected the teaching emphasis observed in the respective cultures. It was concluded that aikido instructors represented the values of their own culture in the context of aikido training, and thus served as important mediating forces influencing the meaning which practitioners generated for aikido. An additional finding revealed that in neither culture were participants able to accurately represent how practitioners in the “other” culture structured their understandings of aikido. It was reasoned that both cultural groups generated faulty perceptions of how the “other” group understood aikido because they utilized a similar pattern of projection, using their own meanings of aikido to represent the understandings of practitioners in the “other” cultural group. 相似文献
845.
Miller LE Pierson LM Nickols-Richardson SM Wootten DF Selmon SE Ramp WK Herbert WG 《Research quarterly for exercise and sport》2006,77(1):58-63
This study assessed muscular torque and rate of torque development following concentric (CON) or eccentric (ECC) isokinetic training. Thirty-eight women were randomly assigned to either CON or ECC training groups. Training consisted of knee extension and flexion of the nondominant leg three times per week for 20 weeks (SD = 1). Eccentric training increased ECC knee extension and flexion peak torque more than CON training. The ECC group improved acceleration time and time to peak torque with ECC movements versus the CON group. Slow-velocity ECC isokinetic training yielded greater ECC and similar CON torque development gains versus CON training over the course of 20 weeks in young women. 相似文献
846.
The graph-theoretic field model— II. application of multi-terminal representations to field problems
This paper is a sequel to a paper entitled “The Graph-Theoretic Field Model—I: Modelling and Formulations” (1). Herein, the Theory of Multi-Terminal Representations is applied to the Graph-Theoretic Field Model to provide mathematical models of finite elements. The element models are obtained solely from the algebraic building blocks of the Graph-Theoretic Field Model, without recourse to any functional mathematics. The theory of Multi-Terminal Representations is developed for both linear and non-linear problems. Examples of the application of the theory to one- and two-dimensional field problems are presented from heat conduction and electrostatics. 相似文献
847.
J.E. Rubio 《Journal of The Franklin Institute》1980,309(5):301-308
Control problems in Hilbert spaces are treated in a measure-theoretical framework; instead of dealing with a set of admissible trajectory-control pairs, a set of measures defined by the boundary conditions and the differential equations of the problem are considered. The concept of weak controllability is introduced; a system has this property if every pair of initial and final points, (ta,xa) and (tb,xb) can be weakly joined; this is possible if a set of linear equalities involving measures has a solution. In turn, this is shown to be equivalent to the possibility of extending a linear functional in a positive manner. Necessary and sufficient conditions for controllability are derived, and applied to the study of a finite-dimensional system with the control appearing linearly. 相似文献
848.
In this paper the problem of memoryless discrete time detection of a constant signal in additive φ-mixing noise is considered. The fidelity criterion is taken to be the asymptotic relative efficiency. The optimal detector nonlinearity is approximated by a polynomial, and the statistical knowledge required for the design of the detector is the family of joint moments of the noise, resulting in a very simple design procedure for the detector. It is shown that the performance of this detector can be made arbitrarily close to that of the optimal memoryless detector for a large class of noises. 相似文献
849.
K.B. Datta 《Journal of The Franklin Institute》1980,309(2):103-123
850.
A.M. Morshedi 《Journal of The Franklin Institute》1980,310(2):89-105
Optimum process operating conditions are often achieved by on-line computer programming. A general method has been developed which is capable of optimizing processes whose responses are corrupted by random error. The method is particularly useful for application to processes whose response functions contain sharp ridges. Application to ridge and non-ridge systems gives the same results in each case showing that the rate of convergence of the search is totally unaffected by the presence of a ridge. An accelarated gradient method is used which obtains its derivatives from a quadratic interpolation. The inability of the gradient method to move along a ridge is overcome by projecting a straight line through points on the ridge to obtain new starting points for a gradient search. Points on the ridge are located by finding the stationary point of the polynomial which is constructed by regression through points found by the gradient search. The method is applied to several test functions known to the literature—a fast convergence rate is obtained for a wide range of noise levels. 相似文献