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11.
石铸 《中国科学院研究生院学报》1981,19(3):318-322
This paper is the documentation of specimens and literature reffered to Atracty-
lodes lancea (Thunb.) DC. etc. As a result, it is found that, in taxonomy of the genus
Atractylodes, what represcents by four long-established names, i. e. Atractylodes lancea
(Thunb.) DC., A. ovata (Thunb.) DC., A. chinensis (Bunge) Koidz. and A. lyrata
Sieb. et Zucc., in fact, is the one and same species. According to the law of priority in
nomenclature, the first name should be given to Chinese drug “Cangzhu”, while theother three names have to be treated as its synonyms. 相似文献
12.
石铸 《中国科学院研究生院学报》1989,27(6):457-460
Two new species of the genus Notoseris (Compositae) are describep
from Sichuan Province, China. They are Notoseris nanchuanensis Shih, N. dolicho-
phylla Shih. 相似文献
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A new combined time and frequency domain method for the model reduction of discrete systems in z-transfer function is presented. First, the z-transfer functions are transformed into the w-domain by the bilinear transformation, z = (1+w)/(1?w). Then, four model reduction methods—Routh approximation, Hurwitz polynomial approxima- tion, stability equation, and retaining dominant poles—are used respectively to reduce the order of the denominator polynomials in the w-domain. Least squares estimate is then used to find the optimal coefficients in the numerator polynomials of the reduced models so that the unit step response errors are reduced to a minimum. The advantages of the proposed method are that both frequency domain and time domain characteristics of the original systems can be preserved in the reduced models, and the reduced models are always stable provided the original models are stable. 相似文献
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Jennifer L. Etnier Paul M. Sprick Jeffrey D. Labban Chia-Hao Shih Stephen M. Glass Jarod C. Vance 《Journal of sports sciences》2020,38(19):2264-2272
ABSTRACT Meta-analytic evidence supports that exercise has benefits for short-term memory (STM) and long-term memory (LTM). However, only three studies with children have tested the differential effects of exercise on STM and LTM. The purpose of this study was to examine the effects of an aerobic fitness test on STM and LTM and to consider the moderating effects of grade level. Children (7–13 years of age) were randomly assigned to either perform an aerobic fitness test before (exercise prior) or after (exercise post) performing the Rey Auditory Verbal Learning Test (RAVLT) to assess memory. Memory was tested again after approximately 24 hours. There were significant differences in memory performance as a function of grade with 4th and 6th graders consistently outperforming 2nd graders. For learning, Day 1 Retention, 24-hr recall, and Day 2 Retention, the exercise prior group performed better than the exercise post group. It is concluded that an aerobic fitness test performed prior to a declarative memory test benefits LTM as compared to when the aerobic fitness test is performed after the memory test. 相似文献