媒体资产管理系统概述

媒体资产管理系统的出现解决了当前存储和管理的一些迫切问题,也为将来的系统升级和电视台数字化系统的融合提出了全新的解决方案。文章对媒体资产管理系统做了概述。     

Validity of students’ evaluations of teaching: Biasing effects of likability and prior subject interest

This study examined the validity of students’ evaluations of teaching as an instrument for measuring teaching quality by examining the effects of likability and prior subject interest as potential biasing effects, measured at the beginning of the course and at the time of evaluation. University students (N = 260) evaluated psychology courses in one semester at a German university with a standardized questionnaire, yielding 517 data points. Cross-classified multilevel analyses revealed fixed effects of likability at both times of measurement and fixed effects of prior subject interest measured at the beginning of the course. Likability seems to exert a substantial bias on student evaluations of teaching, albeit one that is overestimated when measured at the time of evaluation. In contrast, prior subject interest seems to introduce a weak bias. Considering that likability bears no conceptual relationship to teaching quality, these findings point to a compromised validity of students’ evaluations of teaching.     

李大钊《我的马克思主义观》的基本内容、显著特点及其启示

李大钊在《我的马克思主义观》中对马克思主义的三个组成部分进行了系统深入和富有特色的诠释,从而有力地推动了马克思主义在当时中国的广泛传播。著作中体现了李大钊独立思考而不盲从的理性精神、实事求是的科学精神、与时俱进的开拓精神、海纳百川的借鉴精神。在全面建成小康社会和实现中华民族伟大复兴的新时期,重温这篇光辉著作,中国共产党人仍旧能够从中得到做好马克思主义研究和传播工作的重要启示。     

大科学工程高精密光学元器件研制的技术成熟度评价实证研究

研究大科学工程巨型激光装置建设所需的高精密光学元器件研制技术成熟度评价体系,提出光学元件研制的技术成熟度评价方法、评价等级、评价要素和评价流程。基于该体系对关键元件研制技术成熟度评价进行实证应用,评价结果对巨型激光装置的工程设计提供重要参考,降低巨型激光装置研制风险及光学元件供货对巨型激光装置研制进度的影响。     

腺药珍珠菜挥发性成分分析

采用气质联用分析仪分析测定了腺药珍珠菜中56个挥发性组分,其中醚萃取液挥发性组分主要包括亚麻油酸乙酯、2,6十六烷基-1（＋）-抗坏血酸酯、6,9,12,15-二十二碳四烯酸甲酯及棕榈酸乙酯;乙酸乙酯萃取液挥发性组分主要有异佛尔酮衍生物、环氧化红没药烯、富马酸二丁酯及阿魏酸等。     

基于简化相分量法的低压配电网线损量化分析

本文提出了低压配电网的简单相间去耦的相分量法。本文又提出了考虑无功功率的线损简化计算方法,使得线损计算更加准确,并且便于无功补偿的分析。     

Changes in energy availability across the season in Division I female soccer players

Abstract

Low energy availability [(energy intake – exercise expenditure)/kg lean body mass], a component of the Female Athlete Triad, has been associated with menstrual disturbances and low bone mass. No studies have examined the energy availability of athletes across a season. The purpose of this study was to assess the prevalence of, and what contributes to, low energy availability in Division I female soccer players across a season. Nineteen participants aged 18–21 years (mean [Vdot]O_2max: 57.0 ± 1.0 mL · kg^?1 · min^?1) were studied during the pre, mid, and post season. Mean energy availability was overall lowest at mid season, and lower at mid than post season (35.2 ± 3.7 vs. 44.5 ± 3.7 kcal · kg^?1 lean body mass, P = 0.009). Low energy availability (<30 kcal · kg^?1 lean body mass) was observed in 5/19 (26.3%), 5/15 (33.3%), and 2/17 (11.8%) of participants during the pre, mid, and post season. Dietary energy intake was lower mid (P = 0.008) and post season (P = 0.022) than it was pre season (pre: 2794 ± 233 kcal · day^?1; mid: 2208 ± 156 kcal · day^?1; post: 2161 ± 143 kcal · day^?1). Exercise energy expenditure decreased significantly (P ≤ 0.001) over time (pre: 819 ± 57 kcal · day^?1; mid: 642 ± 26 kcal · day^?1; post: 159 ± 28 kcal · day^?1). Low energy availability was due to lower dietary energy intake at lunch during pre season (P = 0.014) and during lunch and dinner during mid season (P ≤ 0.030). Energy availability was inversely related to body dissatisfaction (r = ?0.62, P = 0.017) and drive for thinness (r = ?0.55, P = 0.041) during mid season. Although most Division I female soccer players are not at risk for low energy availability, a concerning proportion exhibited low energy availability at pre or mid season. Further studies are needed to explore strategies to prevent and monitor low energy availability in these athletes.     

Components of Conceptual Ecologies

The theory of conceptual change is criticized because it focuses only on supposed underlying logical structures and rational process processes, and lacks attention to affective aspects as well as motivational constructs in students’ learning science. This is a vast underestimation of the complexity and diversity of one’s change of conceptions. The notion of conceptual ecology provides a context for understanding individuals’ conceptual change learning, as it is the environment through which all information is interpreted. This research investigated how high school students’ statements, made in answering questions, reflect selected components of their conceptual ecologies. Data for this study was collected from six interviews in which seven students took part. The data also include the science teacher’s profiles of each student, the students’ personal journals, their assignments, and their examinations and answers in class. The analysis presented will here include only those components that were represented in the discourse of the seven high school students who were interviewed. When students were asked questions, there was evidence of the engagement of the various components of conceptual ecologies. These components include: epistemological commitments, metaphysical beliefs, the affective domain and emotional aspects, the nature of knowledge, the nature of learning, the nature of conceptions, and past experience. Evidence from this study suggests that these components might function as constraints to learning. This study contributes to the field by expanding our knowledge of the components of high school students’ conceptual ecologies through its definition of the categories and themes associated with those components. In examining across the range of components, the study illustrates the variety and sources of science conceptions within high school students’ conceptual ecologies.     

部首刍议

部首主要用于给汉字分类，从古至今，部首经历了三个发展阶段，由《说文解字》至《字汇》为第一阶段，这一时期的部首主要指出汉字的意义所属，凡是属于同一意义范畴的字归在同一部首；由《字汇》至《康熙字典》为第二阶段，这一时期的部首既重视表意。又注意到表形，凡是属于同一意义范畴的字，形体偏旁相同的排列在一起；由《康熙字典》至今为第三个阶段，这一时期的部首偏重汉字的形体，主要是为了人们检字方便，只要是具有共同形体偏旁的字即使不属同一意义范畴也归在同一部首。