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71.
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
72.
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
73.
74.
F. Fallside 《Endeavour》1979,3(2):63-68
While the majority of those afflicted with deafness must still seek relief by conventional methods, new technological developments open up the possibility of aids of quite novel kinds. This article reviews the principal lines of research now being pursued. 相似文献
75.
John G Landels 《Endeavour》1979,3(1):32-37
The water-clock was the first mechanical device for time measurement to be used by the Greeks. Previously they had relied on sundials, or observation of the phases of the moon or the position of the sun in the zodiac to locate points of time within the day, month or year; and by the mid-fifth century BC they had made some progress with the difficult calendar problems due to the fact that the solar day, the lunar month, and the solar year are not commensurable with each other in whole numbers. 相似文献
76.
The classical criteria for controllability and observability are given a tensorial formulation which is then extended into Boolean form directly related to a digraph interpretation of system structure. This is examined in detail with particular reference to group theoretic aspects, invariant properties under transformation, the term rank test and the existence of zero eigenvalues.Within this framework the structural design concepts of potential controllability and observability are presented in generalised terms. 相似文献
77.
The graph theoretic aspects of controllability and observability are examined and related to the tensorial formulation of Part I of the paper. Particular emphasis is given to the significance of the system digraph decomposition and the relevance of this to certain system algebraic properties of interest in control theory. 相似文献
78.
John OReilly 《Journal of The Franklin Institute》1979,307(3):193-202
The problem of least-squares state estimation of stochastic continuous-time linear systems is reconsidered. A concise derivation of the least-squares minimal-order estimator is presented using an innovations approach. An important result is the reinstatement of the problem in a least-squares estimation framework independent of deterministic observer theory. A second result is thus the clarification of previous approaches to the problem, particularly in relation to observer theory. 相似文献
79.
80.
48 healthy neonates born to multiparae were randomly assigned to view a moving stimulus either in the horizontal or the upright position, with or without added vestibular stimulation and with or without pacifier sucking. The infant was shown a moving black line inside a strictly controlled visual environment provided by an apparatus which permitted horizontal and upright positioning and displacement of the infant. Visual tracking was recorded by a concealed TV camera positioned at a constant distance and angle from the infants' eyes in both positions. Quality of tracking during each of 4 trials was scored on a 7-point scale. Results indicate that vestibularproprioceptive stimulation provided to the infant either horizontally or semivertically significantly enhanced his visual tracking, whereas the upright position did not. Pacifier sucking also improved his performace. 相似文献