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31.
计算机选修课程是计算机教育的一个非常重要的分支,是跨学科、跨专业的桥梁。课程设置的目的是让学生真正学到知识,掌握技能。但在以往选修课的设置中并没有考虑周全,以至于没有起到桥梁的作用。因此,做好计算机选修课程的资源优化配置势在必行。  相似文献   
32.
The purpose of this study was to investigate the use of a single 3-min all-out maximal effort to estimate anaerobic capacity (AC) through the lactate and excess post-exercise oxygen consumption (EPOC) response methods (AC[La?]+EPOCfast) on a cycle ergometer. Eleven physically active men (age?=?28.1?±?4.0?yrs, height?=?175.1?±?4.2?cm, body mass?=?74.8?±?11.9?kg and ?O2max?=?40.7?±?7.3?mL?kg?1?min?1), participated in the study and performed: i) five submaximal efforts, ii) a supramaximal effort at 115% of intensity of ?O2max, and iii) a 3-min all-out maximal effort. Anaerobic capacity was estimated using the supramaximal effort through conventional maximal accumulated oxygen deficit (MAOD) and also through the sum of oxygen equivalents from the glycolytic (fast component of excess post-exercise oxygen consumption) and phosphagen pathways (blood lactate accumulation) (AC[La?]+EPOCfast), while during the 3-min all-out maximal effort the anaerobic capacity was estimated using the AC[La?]+EPOCfast procedure. There were no significant differences between the three methods (p?>?0.05). Additionally, the anaerobic capacity estimated during the 3-min all-out effort was significantly correlated with the MAOD (r?=?0.74; p?=?0.009) and AC[La?]+EPOCfast methods (r?=?0.65; p?=?0.029). Therefore, it is possible to conclude that the 3-min all-out effort is valid to estimate anaerobic capacity in physically active men during a single cycle ergometer effort.  相似文献   
33.
分析双边贸易强度、产业结构相似度、出口结构相似度和产业内贸易指数与经济周期协动性的相关性,利用1990-2011年的季度数据建立OLS与3SLS模型对比分析中日经济周期协动性的贸易传递效应,研究结果表明:双边贸易强度、产业结构相似度、出口结构相似度以及产业内贸易与经济周期协动性是正相关的;在经济周期协动性的贸易传导因素中,产业结构相似度对经济周期协动性的影响系数最小,出口结构、产业内贸易相似度对经济周期协动性的影响较大.  相似文献   
34.
设G=(V,E)是一个n阶简单图,若对于每一个k(3燮k燮n),G都含有长度为k的圈Ck,则称G为泛圈图。利用图的闭包理论研究图的补图谱半径的界,讨论了泛圈图存在的一个谱条件。  相似文献   
35.
This study aimed to analyse the effects of a simulated Brazilian jiu-jitsu (BJJ) tournament on vertical jump performance, grip strength test and perceived effort responses. 22 male BJJ athletes participated in a simulated tournament consisting of three 7 min matches separated by 14 min of rest. Kimono grip strength test (KGST), counter movement jump (CMJ) and rate of perceived exertion (RPE) were measured before and after each match, while RPE of specific areas was assessed after three matches. ANOVA for repeated measures was used to compare strength parameters after each match with the level of significance set at 5%. The key results showed a significant decrease of jump height (p = 0.001) and net vertical impulse in the CMJ (p = 0.031), as well as a reduction of the number of reps in the KGST (p < 0.001). A significant increase of RPE was found throughout the matches (p < 0.001). Considering the RPE in specific areas, no differences were observed between the upper and lower body (p = 0.743). We conclude that the BJJ simulated tournament generated a decrease of performance in both upper and lower limbs and provoked a progressive increase in the effort perception over the matches.  相似文献   
36.
基于零增长理论的随书光盘系统实践   总被引:3,自引:0,他引:3  
蔡琦 《河南图书馆学刊》2007,27(6):82-83,122
介绍图书馆随书光盘系统遇到的问题,结合零增长理论和信息生命周期的相关概念,提出随书光盘系统的改进思路,并提供实现的软件原型.  相似文献   
37.
朱启娥 《湖北体育科技》2010,29(4):435-436,418
目的:探讨大运动量训练致运动疲劳后,按摩和艾灸穴位对疲劳恢复和相关生化指标的影响。方法:以16名体育学院武术专业学生为试验对象,在不同时间(间隔两周)分别进行两次大运动量训练至中等以上疲劳程度,分别对受试对象进行按摩和艾灸穴位,测试不同时间点的血氨和血尿素值,并对两次实验结果进行自身对照。按摩组为A组,艾灸组为B组。结果:B组的血氨浓度在恢复期的各个时间点上都低于A组,第15min钟和第3min差异非常显著(P〈0.01),第45min和第60min差异显著(P〈0.05);B组血尿素的恢复速度也快于A组,第90min明显低于A组(P〈0.05),次日晨B组较A组恢复更加明显(P〈0.01)。结论:艾灸穴位比按摩能更快清除血氨和血尿素,从而更好地促进运动性疲劳的恢复。  相似文献   
38.
观察15名民族传统体育专业大学生在武术大负荷训练前后血乳酸和血尿素氮的变化,分析血乳酸和血尿素氮与民族传统体育大学生训练水平的关系,结果表明:血乳酸和血尿素氮能够客观评定训练强度,为科学训练提供依据;大运动负荷训练对学生血乳酸和血尿素氮变化有不同程度的影响,但存在个体差异。  相似文献   
39.
Abstract

The aim of this study was to compare optimization and correction procedures for the determination of peak power output during friction-loaded cycle ergometry. Ten male and 10 female sports students each performed five 10-s sprints from a stationary start on a Monark 864 basket-loaded ergometer. Resistive loads of 5.0, 6.5, 8.0, 9.5, and 11.0% body weight were administered in a counterbalanced order, with a recovery period of 10 min between sprints. Peak power was greater and occurred earlier, with less work having been done before the attainment of peak power, when the data were corrected to account for the inertial and frictional characteristics of the ergometer. Corrected peak power was independent of resistive load (P > 0.05), whereas uncorrected peak power varied as a quadratic function of load (P < 0.001). For males and females, optimized peak power (971 ± 122 and 668 ± 37 W) was lower (P < 0.01) than either the highest (1074 ± 111 and 754 ± 56 W respectively) or the mean (1007 ± 125 and 701 ± 45 W respectively) of the five values for corrected peak power. Optimized and mean corrected peak power were highly correlated both in males (r = 0.97, P < 0.001) and females (r = 0.96, P < 0.001). The difference between optimized and mean corrected peak power was 37 ± 30 W in males and 33 ± 14 W in females, of which approximately 15 W was due to the correction for frictional losses. We conclude that corrected peak power is independent of resistive load in males and females.  相似文献   
40.
谢刚  张金隆 《科研管理》2006,27(3):97-102,89
文章研究了将项目管理风险集成到投标风险,运用全寿命周期理论实施软件项目投标风险规避的问题。首先,介绍了软件项目全寿命周期流程和寿命周期各阶段的主要风险要素;其次,分析了软件项目投标风险对应的风险规避措施;最后,提出了软件项目投标风险规避的基本决策过程,并举例。  相似文献   
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