A developmental study of information processing within the first three years of life: response decrement to a redundant signal     

M Lewis  S Goldberg  H Campbell 《Monographs of the Society for Research in Child Development》1969,34(9):1-41

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Braided composite materials for the production of lightweight, high rigidity golf shafts   总被引：1，自引：1，他引：0  

Douglas Steven S. Swanek  Jason Carey 《Sports Engineering》2007,10(4):195-208

Braiding is not currently used in the production of golf shafts. The objective of this work was to develop, through a modelling process consisting of altering lamina sequence, a golf shaft, using braided laminas, which would have mass, stiffness and torque comparable to commercially available composite and steel shafts. A 2D conical braided composite model was previously developed and validated to predict elastic constants of braided closed meshed structures. Energy methods were used to calculate the stiffness and torque of shafts using prescribed industry approaches. Shaft mass was calculated based on geometry and density of constitutent materials. Modelled shafts had both braided and unidirectional layers and compared favourably with or were better than commercially available composite and steel shafts in terms of deflection force and twist angle; they had the same weight as composite shafts but were much lighter than steel shafts. If these findings are verified, braided composites would be a viable and effective approach to the design of future golf shafts.  相似文献   

A study of operant conditioning under delayed reinforcement in early infancy     

W S Millar 《Monographs of the Society for Research in Child Development》1972,37(2):1-44

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Noun-pair learning in children and adults: underlying strings and retrieval time     

N S Suzuki 《Child development》1972,43(1):299-307

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Neuromuscular, metabolic and hormonal profiles of young tennis players and untrained boys   总被引：2，自引：1，他引：1  

A Mero  L Jaakkola  P V Komi 《Journal of sports sciences》1989,7(2):95-100

This study compared the neuromuscular, metabolic and hormonal profiles of trained prepubescent tennis players and an untrained group. The boys in the experimental group (n = 9; mean age +/- S.D. = 11.4 +/- 0.5 years) had participated in tennis training for 2.3 +/- 1.0 years and the boys in the control group (n = 9; mean age +/- S.D. = 10.9 +/- 0.4 years) were normal active volunteers. The tennis players were found to be physically more active than the controls when the comparison was made for either 1 year (4.9 +/- 1.8 vs 2.6 +/- 2.5 times per week; P less than 0.05) or for 1 week (3.4 +/- 1.2 vs 0.4 +/- 0.5 times; P less than 0.001) preceding the tests. Choice reaction time was significantly (P less than 0.01) shorter in the experimental group (258 +/- 16 ms) than in the control group (344 +/- 81 ms). Dropping height in the best drop jump was significantly (P less than 0.05) higher in the tennis players (0.46 +/- 0.19 m) than in the control boys (0.27 +/- 0.10 m). The tennis players had significantly lower oxygen consumption at the 'anaerobic threshold' than the controls (P less than 0.05). There were no significant differences between the groups in serum hormone levels. The small differences that existed may have been caused by active participation in sport by the tennis players.  相似文献   

Update on inflation of journal prices: medical journals, U.S. journals, and Brandon/Hill list journals     

M R Kronenfeld  S H Gable 《Bulletin of the Medical Library Association》1989,77(1):61-64

This paper examines the increases in prices for the last twenty years for the journals listed in the 1987 Brandon/Hill list and for the last twelve years for those on a list of medical and general periodicals published annually in Library Journal. This information is compared to the general U.S. inflation rate as measured by the Consumer Price Index. Despite the decline in the general rate of inflation, the buying power of libraries has continued to dwindle. Librarians need to use this information when justifying increased budget requests. They also need to interact more effectively with publishers to resolve this problem. The buying power of the dollar (as compared to the 1975 dollar) spent on the Brandon/Hill list journals is now 59% of that of a dollar spent in the general economy. This compares to 64% in 1983, when this research was last updated.  相似文献   

Work/training programs for international health science librarians in American medical school libraries     

P W Brennen  M B Gorman Sullivan 《Bulletin of the Medical Library Association》1989,77(2):170-175

World understanding is more than a desirable goal today: it may be crucial to our survival. Many universities realize this and have in the past decade spent a great deal of time and money to ensure a steady flow of faculty and students between the U.S. and other countries. Librarians with faculty or academic status may benefit from promoting such relationships themselves. Job exchanges and training programs offer librarians in the United States the opportunity to become acquainted with their counterparts in other countries. Such programs enable librarians of various countries to become aware of one another's special needs and common problems, and allow them to share ideas and expertise. This paper presents an overview of international training programs for foreign librarians in the United States, focusing on programs for health sciences librarians in United States medical school libraries. Information is given on the availability and types of institutionally sponsored programs, as well as on MLA's Cunningham Fellowship Program. Some of the difficulties and the benefits of such programs are discussed.  相似文献   

Visions of Evil: Popular Culture,Puritanism and the Massachusetts Witchcraft Crisis of 1692     

Richard P. Gildrie 《Journal of American culture (Malden, Mass. : 2003)》1985,8(4):17-33

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Computerized language analysis     

S Ray 《American annals of the deaf》1985,130(5):462-469

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Establishing reliability of biomechanical data using univariate and multivariate approaches     

M A Looney  S L Smith  S Srinivasan 《Research quarterly for exercise and sport》1990,61(2):154-161

The purpose of this study was to use generalizability theory with both univariate and multivariate approaches to examine reliability of total body center of mass (CM) values calculated from cinematographical data. Twenty-eight college-aged male volunteers were filmed by a LOCAM camera at 100 fps while performing the basic locomotion skill of walking. Film analysis was conducted on each subject using six frames of film depicting a one-stride walking cycle consisting of right heel strike, right foot flat, left toe-off, left heel strike, left foot flat, and right toe-off. Nineteen segmental endpoints and a reference point were digitized by three experienced plotters. The digitizing sequence was replicated three times by each plotter. A FORTRAN program calculated nine CM values (three plotters by three repetitions) for each subject filmed in each of the six positions of the stride. The x- and y-coordinates of the CM values were the dependent variables analyzed by fully crossed 3-way univariate and multivariate ANOVAs (subjects by plotters by repetitions). All measurement facets were considered to be random. Results indicate that there was very little repetition error but considerable interplotter error for most frames. Phi-coefficients for x- and y-coordinates, separately, fluctuated across frames. The univariate values for the x-coordinates were similar but slightly less than the multivariate values. The Phi-coefficients for Y, however, were considerably lower than the multivariate values. The multivariate Phi-coefficients for generalizing over three plotters and three repetitions ranged from .82 to .90.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献