大学英语词汇教学策略

词汇教学在大学英语教学中至关重要.目前词汇教学存在种种误区,成为制约学生学好英语的障碍.本文探讨了语境策略、精加工策略、语义场策略、词块记忆策略和元认知策略,以改进大学英语词汇教学现状.     

求解多元函数极值的一种新方法

本文给出了三元函数极值的充分条件和必要条件,并把它推广到了多元函数,给出了求多元函数极值的一个新方法。     

我国沿海地区水产技术推广效率时空演变研究——基于面板三阶段DEA模型的分析

本文基于2006-2016年我国沿海地区水产技术推广的面板数据,运用三阶段DEA模型对沿海11省市剔除环境因素和随机误差项前后的水产技术推广效率进行测度与分析。分析结果表明,沿海地区水产技术推广效率受环境因素影响较大,水产技术推广网站数量、渔民手机数量、渔民人均纯收入和养殖受灾面积对水产技术推广机构、推广人员、推广经费和推广资料影响显著;在剔除环境因素和随机误差项后,大部分地区水产技术推广综合技术效率和规模效率呈现下降,各地普遍处于规模报酬递增状态,规模扩张是技术推广效率提升的关键;2006-2016年,沿海各地区水产技术推广效率变化显著,沿海“渔业大省”水产技术推广效率水平明显优于其他省市。各地区应结合渔业发展现实,挖掘资源优势,加大技术推广投入力度,提高各地区水产技术推广效率。     

从语义角色的变化谈词义的发展——以“暗补”“明补”为例

“暗补”和“明补”是近年来出现的的新词语。它们的深层语义角色施事、目的、范围、动作等在表层语义结构中没有体现出来,因此这些语义角色的具体值会随语境的不同而有所不同。在对“暗补”或“明补”进行定义时,对施事、目的、范围、一动作等语义角色不能定义得十分具体,否则就只能是它的语境义而不是词典中的概念义了。     

College course scarcity and time to degree

College students are taking longer to earn baccalaureate degrees now than ever before, but little is known about institutional factors that may contribute to this trend. In this paper we investigate an important institutional constraint—course scarcity—that we hypothesize may be associated with increased time to degree. We employ a unique administrative dataset from a large, moderately selective, public institution and use an instrumental variables approach, identifying off the random registration times assigned to students. Results suggest that course scarcity does not delay students’ graduation. We explore alternative explanations for our findings and discuss a variety of other factors correlated with time to baccalaureate completion.     

Correlations Among Five Demographic Variables and the Performance of Selected Jamaican 11th-graders on Some Numerical Problems on Energy

This study was designed to assess whether the level of performance of selected Jamaican 11th-grade physics students on some numerical problems on the energy concept was satisfactory and if there were significant differences in their performance linked to their gender, socioeconomic background (SEB), school location, English language and mathematical abilities. The 331 sampled students consisted of 213 boys and 118 girls; 197 students were from a high SEB and 134 students from a low SEB; 296 students were from seven urban schools and 35 students from three rural schools; 112, 153 and 66 of the students had high, average and low English language abilities, respectively, while 144, 81 and 106 of the students had high, average and low mathematical abilities, respectively. An Energy Concept Test (ECT) consisting of six structured numerical questions was employed for data collection. The results indicated that although the students’ level of performance was regarded as fairly satisfactory, there was a lot of room for improvement. There were statistically significant differences in the students’ performance on the ECT linked to SEB, and mathematical abilities in favour of students from a high SEB, and high mathematical abilities, respectively. There was a positive, statistically significant but weak correlation between the students’ (a) mathematical abilities, and (b) English language abilities and their performance on the ECT, while there were no correlations among their gender, school location, and SEB and their performance on the ECT.     

Situated Learning: Conceptualization and Measurement

A focus on the interaction between cognitive schemas and context in situ has been suggested as fundamental in organizational decision making and information interpretation. Past research suggests that the situation and the social interaction that occur during learning at the cognitive level consist of factors that affect the process, but the research lacks a coherent explanation for how those factors affect it. We propose a conceptualization of learning, termed situated learning, which accounts for these factors. By drawing on situated cognition theory, social learning theory, and the theory of mental models, we identify and measure four components of situated learning, that is, thematic focus, cognitive absorption, social structure, and participation. Among the most important lessons for researchers and practitioners is the need to consider learning as a constellation of the four components instead of an indivisible phenomenon. This perspective can enhance our understanding of cognitive processes, such as information interpretation and decision making.     

Hot hands,cold feet? Investigating effects of interacting constraints on place kicking performance at the 2015 Rugby Union World Cup

Place kicks in Rugby Union present valuable opportunities to score points outside the spatiotemporal dynamics of open play but are executed under varying performance constraints. We analysed effects of specific task constraints and relevant contextual factors on place kick performance in the 2015 Rugby Union World Cup. Data were collected from television broadcasts for each place kick. In addition to kick outcomes, contextual factors, including time of the kick in the match, score margin at the time of the kick, and outcome of the kicker’s previous kick, were recorded. Effects of spatial task constraints were analysed for each kick, using distance (m) and angle (°) of the kick to the goalposts. A binomial logistic regression model revealed that distance from, and angle to, the goalposts were significant predictors of place kick outcome. Furthermore, the success percentage of kickers who missed their previous kick was 7% lower than those who scored their previous kick. Place kick success percentage in the 10 minutes before half-time was 8% lower than the mean tournament success percentage, which was 75% (95% CI 71–78%). The highest kick success percentage was recorded when scores were level (83%; 95% CI 72–91%). Our data highlighted how subtle changes in task constraints and contextual factors can influence performance outcomes in elite performers in international competition. Fluctuations in place kick success suggested that individual constraints, such as thoughts, emotions and fatigue, induced during competition, could interact with perceptions to influence emergent performance behaviours.     

Contribution of limbs’ actions to the four competitive swimming strokes: a nonlinear approach

The aim of our study was to assess the effect of the limbs’ actions on the nonlinear properties of the four competitive swimming strokes. Forty-nine swimmers performed all-out sprints at front-crawl, backstroke, breaststroke and butterfly, each one at full stroke (FS), only the arms’ stroke (AS), and only leg kicking (LK), in a total of 12 bouts, 6 per day. A speedo-meter cable was attached to the swimmer’s hip, to collect the speed-time raw data (f = 50Hz). Velocity, speed fluctuation, sample entropy and fractal dimension were derived from the speed-time series. Significant and moderate-strong effects were noted for both stroke and condition in all variables in the study (p ≤ 0.001; 0,560<η² < 0,952). The four competitive strokes and their three conditions exhibited nonlinear properties. The swimming pattern was less complex and more predictable for LK in comparison to AS and FS. Breaststroke and butterfly have more complex but more predictable patterns than backstroke and front-crawl.     

帕森斯的“结构——功能主义”之探析

帕森斯是现代结构功能主义学派的创始人,一生致力于构建一个包罗万象的、宏大社会学体系。帕森斯的研究取得了重大成果,但也遭到了许多批评。但是,即使是批评者也不得不承认,帕森斯的理论是现代社会学的主要参照点。帕森斯的＂结构—功能主义＂主要理论思想——社会系统理论、结构功能模型、社会变迁思想与＂分化＂理论、两分法理论与模式变量理论。