Effects of light refraction on the accuracy of camera calibration and reconstruction in underwater motion analysis

One of the most serious obstacles to accurate quantification of the underwater motion of a swimmer's body is image deformation caused by refraction. Refraction occurs at the water‐air interface plane (glass) owing to the density difference. Camera calibration‐reconstruction algorithms commonly used in aquatic research do not have the capability to correct this refraction‐induced nonlinear image deformation and produce large reconstruction errors. The aim of this paper is to provide a through review of: the nature of the refraction‐induced image deformation and its behaviour in underwater object‐space plane reconstruction; the intrinsic shortcomings of the Direct Linear Transformation (DLT) method in underwater motion analysis; experimental conditions that interact with refraction; and alternative algorithms and strategies that can be used to improve the calibration‐reconstruction accuracy. Although it is impossible to remove the refraction error completely in conventional camera calibration‐reconstruction methods, it is possible to improve the accuracy to some extent by manipulating experimental conditions or calibration frame characteristics. Alternative algorithms, such as the localized DLT and the double‐plane method are also available for error reduction. The ultimate solution for the refraction problem is to develop underwater camera calibration and reconstruction algorithms that have the capability to correct refraction     

以学生为主体的高三生物学实验课教学初探

生物学实验是调动学生学习积极性，使教学过程变得生动活泼、轻松、高效的极好手段，更是培养学生综合素质和创新能力，提高学生科学素养的极好途径。当前，高三的实验教学复习中“背实验，做实验题”的现象仍是普遍存在的，这与高考生物学实验题注重对实验现象和结果的分析、实验方案的设计等能力考查是极不适应的。因此，本人几年来，在兼顾课内实验的基础上，结合备考实际和学生存在的问题，通过实践探索，     

"520化学网络扑克"游戏的开发及其应用

网络时代的来临使人们的学习方式发生了巨大改变,网络教育游戏被越来越多的教育工作者所关注.然而目前国内外与化学学科相结合且针对中学生的网络教育游戏很少,基于此,本文介绍了具有自主知识产权的"学科教育游戏--"520化学网络扑克"游戏的设计,包括"520化学游戏网"的设计和"520化学网络扑克"游戏的设计.同时还对"520化学网络扑克"游戏的应用范围(包括在中学化学学科教学中的应用和在化学第二课堂的应用)以及其在国内外的应用成效进行了初步的探究.结果表明:该游戏不仅能够帮助教师解决化学用语教学难点问题而且为中学生提供自主和合作学习新平台.经过两年的开发与应用,该游戏系统已初具规模,取得了理想的成效.     

Data quality management,data usage experience and acquisition intention of big data analytics

Big data analytics associated with database searching, mining, and analysis can be seen as an innovative IT capability that can improve firm performance. Even though some leading companies are actively adopting big data analytics to strengthen market competition and to open up new business opportunities, many firms are still in the early stage of the adoption curve due to lack of understanding of and experience with big data. Hence, it is interesting and timely to understand issues relevant to big data adoption. In this study, a research model is proposed to explain the acquisition intention of big data analytics mainly from the theoretical perspectives of data quality management and data usage experience. Our empirical investigation reveals that a firm's intention for big data analytics can be positively affected by its competence in maintaining the quality of corporate data. Moreover, a firm's favorable experience (i.e., benefit perceptions) in utilizing external source data could encourage future acquisition of big data analytics. Surprisingly, a firm's favorable experience (i.e., benefit perceptions) in utilizing internal source data could hamper its adoption intention for big data analytics.     

Student–student mentoring for retention and engagement in distance education

This article argues that in the drive to develop e‐learning initiatives in distance learning, simpler ways of supporting students for retention may be overlooked; for example, the linking of students in the form of mentoring and peer support networks. The article reports on three mentoring projects, in the United Kingdom, Korea and New Zealand, and shows that apparent retention gains of up to 20% with a return on investment of the order of magnitude of several hundred per cent may be possible. Whilst accepting the limitations of these studies, the article argues that there needs to be a clearer understanding of the benefits of such initiatives when deciding to invest time and funding in distance education support. It suggests that there is still much mileage to be made out of mentoring and ‘study dating’.     

The Role of Mothers' and Fathers' Parental Control and Coparenting in Toddlers' Compliance

Research Findings: This study examined the unique and relative contributions of mothers' and fathers' parental control and coparenting to toddlers' committed compliance with parents in both dyadic parent–child and triadic family play contexts. Sixty-eight mostly middle-class, 2-parent families with toddlers (16–37 months) were observed in a university laboratory setting. There were positive associations among mothers' gentle guidance, balanced coparental engagement, and child committed compliance with mothers. However, there was no association between any parental control or coparenting variable and child compliance with fathers. Unique contributions of fathers' control and coparenting, beyond mothers' parenting, were found for children's compliance with mothers but not with fathers. Practice or Policy: The findings highlight the importance of taking the family relationship context into account when assessing parenting behaviors and toddlers'compliance.     

Correction to: Neglected Elements of a High-Quality Early Childhood Workforce: Whole Teacher Well-Being and Working Conditions

Early Childhood Education Journal - The original version of this article unfortunately contains some typo in Table 1.     

高校羽毛球选项课中女生群体教学现状及对策探讨

运用文献资料法、问卷调查法及访谈法,对高校羽毛球选项课中的女生群体的学习特点作出分析,从而有针对性的提出加强技术教学、正确把握女生的学习动机和心理动向、对课程本身作出适当改革等一系列措施。     

A cross-cultural study of preschool quality in South Korea and Sweden: ECERS evaluations

The aim of the study is to explore cross-cultural similarities and differences in preschool quality in South Korean and Swedish preschools as measured by two national adaptations of the Early Childhood Environment Rating Scale (ECERS). The approach adopted is that cross-cultural comparisons of preschool quality are both achievable and of great importance to researchers as well as policy-makers, educators, teachers and parents. The results indicate that Swedish childcare programs rate higher on the entire ECERS and all of the individual subscales. The similarities and differences in preschool quality are interpreted within the socio-cultural context of each country and the respective pedagogical goals for preschool.     

R&D,foreign ownership,and corporate groups: Evidence from Japanese firms

This study empirically examines whether the research and development (R&D) activities of foreign-owned firms in Japan differ notably from the R&D activities of domestically-owned firms based on a firm-level panel dataset. Our study carefully disentangles the significant differences in R&D investment behavior of subsidiaries due to three different reasons: having a foreign parent, corporate group affiliation, and the degree of relatedness between business units. The results reveal the following. First, firms that are majority-owned by another firm are less active in R&D than independent firms. Second, foreign ownership does not matter if the parent firm is from a G7 country, but R&D intensity is significantly and positively associated with foreign ownership if the parent firm is from a non-G7 country. Finally, for subsidiaries whose business is related to that of their parent firm, the R&D intensity is lower if the parent is a domestic firm, but higher if it is a foreign firm. These findings imply that globalization and the integration of firms may not only affect production patterns and global supply chains, but may also have an important impact on the level of domestic R&D activities.