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991.
ErnestJ.Dick 《现代声像档案》2006,8(3):4-9
1 介绍
现在,美国的所有商业形式都越来越多地使用声音和图像技术,其他国家也是如此。企业一直都在非常敏捷地捕捉静态画面、声音记录和活动图像。随着声音和图像技术的发展,企业在开发广大的新市场和新机遇方面也是游刃有余,因而,声音和图像资料就迅速普及并积累起来,其速度超出了任何人的想象。 相似文献
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993.
那些经过时光无情的淘洗,依旧光灿如新,甚或散发出更加夺目光芒的作品称之为经典。用有限的时间亲近大师们的经典力作,无疑是智者的选择。 相似文献
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996.
The joint contribution of early parental warmth, communication and tracking, and early child conduct problems on monitoring in late childhood 总被引:1,自引:0,他引:1
The relationship of parental warmth, communication, and tracking (WCT), and child conduct problems in early elementary school (age 5.5 years) to monitoring in late elementary school (age 9.5 years) was longitudinally examined in a sample of 267 boys and girls. WCT in kindergarten was associated with lower kindergarten levels and less growth of conduct problems into the first grade, and was prospectively associated with effective monitoring in the third and fourth grades. Overt and covert conduct problems in kindergarten and growth in covert problems during kindergarten and first grade were associated with less effective later monitoring. Early conduct problems mediated the prospective association of WCT on later monitoring. The results are described in a transactional model of parent-child relationships and child problem behavior. 相似文献
997.
OBJECTIVE: This paper explores the characteristics associated with decisions to adopt or discontinue the use of filtering software, including a critical analysis of some explanations about why it is used or not used in households with children and adolescents. METHOD: This study consisted of a national telephone survey of households in the United States with youth (10 and 17 years) who use the Internet regularly. Interviews were completed with one youth in the appropriate age group and a parent or caretaker. RESULTS: Thirty-three percent of parents reported using filtering or blocking software, with an additional 5% having discontinued its use within the past year. Parents were more likely to adopt filtering software if they had younger children (10--15 years), a high level of concern about exposure to sexual material on the Internet, more extensive knowledge of what their child did online, low trust in the child's ability to use the Internet responsibly, and if the child used America Online (AOL). Using the Internet for school assignments was associated with not having filtering software. CONCLUSION: Findings suggest the need for (1) evaluation research of filter programs used in a real family context and (2) the development of a variety of strategies to prevent exposure to inappropriate material for youth of different ages. 相似文献
998.
Maturity-associated variation in sport-specific skills of youth soccer players aged 13-15 years 总被引:1,自引:1,他引:0
Malina RM Cumming SP Kontos AP Eisenmann JC Ribeiro B Aroso J 《Journal of sports sciences》2005,23(5):515-522
The aim of this study was to estimate the contribution of experience, body size and maturity status to variation in sport-specific skills of adolescent soccer players. The participants were 69 players aged 13.2-15.1 years from three clubs that competed in the highest division for their age group. Height and body mass were measured and stage of pubic hair development was assessed at clinical examination. Years of experience in football was obtained at interview. Six football skill tests were administered: ball control with the body, ball control with the head, dribbling with a pass, dribbling speed, shooting accuracy and passing accuracy. Multiple linear regression analysis was used to estimate the relative contributions of age, stage of sexual maturity, height, body mass and years of formal training in soccer to the six skill tests. Age, experience, body size and stage of puberty contributed significantly but in different combinations to the variance in four of the six skill tests: dribbling with a pass (21%; age, stage of maturity), ball control with the head (14%; stage of maturity, height, body height x body mass interaction), ball control with the body (13%; stage of maturity, years of training) and shooting accuracy (8%; stage of maturity, height; borderline significance, P = 0.06). There were no significant predictors for the tests of dribbling speed and passing accuracy. In conclusion, age, experience, body size and stage of puberty contributed relatively little to variation in performance in four of the six soccer-specific skill tests in adolescent footballers aged 13-15 years. 相似文献
999.
The relative age effect in youth soccer across Europe 总被引:2,自引:2,他引:0
The potential asymmetries in the birth-date distributions of youth soccer players across ten European countries (2175 age citations) were considered. First, we examined the birth-dates of players representing national youth teams in international competitions. Second, the birth-dates of players representing professional club teams in international youth tournaments were analysed. Kolmogorov-Smirnov tests were used to assess differences between observed and expected birth-date distributions. Regression analyses were employed to examine the relationship between month of birth and number of players in the different samples. The results showed an over-representation of players born in the first quarter of the selection year (from January to March) for all the national youth selections at the under-15 (U-15), U-16, U-17 and U-18 age categories, as well as for the UEFA U-16 tournaments and Meridian Cup. Players with a greater relative age are more likely to be identified as "talented" because of the likely physical advantages they have over their "younger" peers. Some options for reducing the relative age effect are offered. 相似文献
1000.
Li J Runderson RA Burnham JF Staggs GB Robertson JC Williams TL 《Medical reference services quarterly》2005,24(1):41-54
This article reports on a project that delivers distance training to rural health care professionals. Traveling to provide training on information-seeking skills to rural health professionals is time consuming and costly. In addition to face-to-face training, the University of South Alabama Biomedical Library's SAMNet project seeks to deliver multimedia training to rural health care professionals. The project uses information technology to package training courses combining PowerPoint slides and video instructions. This article describes the rationale, training module design and development, and the information technology and software used in the project. Multimedia packaged distance training courses provide a practical alternative to on-site training for rural health care professionals. It enables librarians to provide training without traveling long distance, thus saving time and money. Additionally, rural health care professionals may access the modules at a time convenient to them and proceed at a pace suitable to their learning style. 相似文献