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141.
We designed support for volitional control with four stages for goal initiation (“Want it”), goal formation (“Plan for it”), action control (“Do it”), and emotion control (“Finish it”) based on theories and models of volition. We implemented the support in mathematics courses offered at a community college. We examined the effects of volitional control support on students’ motivation (i.e., intrinsic value, self-efficacy), emotions (enjoyment, pride, anger, anxiety, shame, hopelessness, and boredom), effort regulation, and achievement. We found significant effects of the volitional control support on intrinsic value, enjoyment, anger, anxiety, and boredom. Findings are discussed to improve the design and development of the volitional control support. Limitations and implications of the study are presented as well.  相似文献   
142.
This study examined the effects of professional development on teachers’ assessment literacy between two groups of teachers: (1) teachers who were involved in ongoing and sustained professional development in designing authentic classroom assessment and rubrics; and (2) teachers who were given only short-term, one-shot professional development workshops in authentic assessment. The participating teachers taught Year 4 and 5 English, science, and mathematics. The findings showed that the assessment literacy of teachers who were involved in ongoing, sustained professional development had increased significantly during the second year of study. These teachers had also gained a better understanding of authentic assessment.  相似文献   
143.
This study investigates the socialization and professional experiences of primary school physical education teachers (PSPETs) in the Asian context of Hong Kong. A qualitative research design is adopted. The researcher used semi-structured interviews, supplemented by documentary sources (diaries) for conducting data collection. Eleven PSPETs participated in this study. Data were analysed through open axial and selective coding. The concepts of organizational sensitivity, sources of satisfaction, dealing with influential persons or critical incidents, status of the profession, educational reform as a trend, and versatile roles are revealed in the theory of ‘Diversified Professionalism’. The substantive theory thus contributes to an increased appreciation of the PSPETs’ work and to the literature on physical education teachers’ professionalization and professionalism.  相似文献   
144.
In this paper, we consider the super-twisting observer-based sliding mode control algorithm with fuzzy variable gains (STOSMC) for the fully-actuated hexarotor. Our hexarotor has full actuation due to six titled propellers that allows to control position and orientation (attitude) simultaneously, and resolves the singularity problem of the rotational matrix by using the quaternion modeling framework. We show that the proposed STOSMC for the hexarotor guarantees finite-time convergence of the estimation error and asymptotic stability of the hexarotor. In simulations, we demonstrate the nonsingularity and fully-actuated control performance of the hexarotor by considering extreme position and attitude control scenarios. Moreover, the simulation results show that the hexarotor achieves the fast and precise tracking performance to the desired position and the desired attitude and the chattering phenomenon is reduced compared with the fixed-gains observer-based super-twisting sliding mode control due to the fuzzy mechanism.  相似文献   
145.
We study the role of the relationship among inventors and intermediaries in the licensing of university inventions. We suggest that a prior inventor-intermediaries relationship positively influences licensing rates through selective retention of higher quality relationships and mutual learning in the relationship, enabling intermediaries to reduce both information asymmetry and search costs between inventors and potential licensees. We argue that the influence of a prior inventor-intermediaries relationship on licensing is especially important before intellectual property protection is attained and can be substituted by the buyer-side contacts of inventors and intermediaries. We test these predictions using 919 inventions from the technology transfer office at Stanford University. This study has implications for the policies and design of university technology licensing organizations.  相似文献   
146.
Abstract

In recent years, volunteering has received strong research attention from both scholars and practitioners. For the most part, involvement in volunteer activities has been identified as an important determinant of future volunteering. Through revalidating an existing instrument, the purpose of this study was to assess the dimensions of volunteer satisfaction at the 2012 London Olympic Games and its impact on future volunteer behaviour. The findings of this study shed light on the identification of volunteer satisfaction factors in the mega sporting event setting, particularly for a unique type of volunteer (i.e. media worker) assigned to a special set of tasks. Unlike Galindo-Kuhn and Guzley’s results that revealed participation efficacy and group integration to be strong predictors of volunteer satisfaction, organizational support was the primary predictor for media centre volunteers’ re-participation intention towards future volunteering programmes.  相似文献   
147.
Purpose:To investigate whether blood flow restriction(BFR) without concomitant exercise mitigated strength reduction and atrophy of thigh muscles in subjects under immobilization for lower limbs.Methods:The following databases were searched:PubMed,CINAHL,PEDro,Web of Science,Central,and Scopus.Results:The search identified 3 eligible studies,and the total sample in the identified studies consisted of 38 participants.Isokinetic and isometric torque of the knee flexors and extensors was examined in 2 studies.Cross-sectional area of thigh muscles was evaluated in 1 study,and thigh girth was measured in 2 studies.The BFR protocol was 5 sets of 5 min of occlusion and 3 min of free flow,twice daily for approximately 2 weeks.As a whole,the included studies indicate that BFR without exercise is able to minimize strength reduction and muscular atrophy after immobilization.It is crucial to emphasize,however,that the included studies showed a high risk of bias,especially regarding allocation concealment,blinding of outcome assessment,intention-to-treat analyses,and group similarity at baseline.Conclusion:Although potentially useful,the high risk of bias presented by original stodies limits the indication of BFR without concomitant exercise as an effective countermeasure against strength reduction and atrophy mediated by immobilization.  相似文献   
148.
ABSTRACT

Research on media substitution theory has examined substitutional and/or complementary relationships between new and existing media. This study focuses on the growth of mobile platforms and investigates the relationship between mobile devices and personal computers. Using Nielsen’s panel data that provide electronically recorded media usage (N = 2,396), this study analyzes yearly changes in time allocation to mobile devices and PCs at total and content-specific usage levels during mobile 4G transition. Results suggest a complementarity dynamic between mobile devices and PCs; however, the patterns were more nuanced in light of the role of individual and structural factors when determining media choice.  相似文献   
149.
Many prominent intelligence tests (e.g., Wechsler Intelligence Scale for Children, Fifth Edition [WISC-V] and Reynolds Intellectual Abilities Scale, Second Edition [RIAS-2]) offer methods for computing subtest- and composite-level difference scores. This study uses data provided in the technical manual of the WISC-V and RIAS-2 to calculate reliability coefficients for difference scores. Subtest-level difference score reliabilities range from 0.59 to 0.99 for the RIAS-2 and from 0.53 to 0.87 for the WISC-V. Composite-level difference score reliabilities generally range from 0.23 to 0.95 for the RIAS-2 and from 0.36 to 0.87 for the WISC-V. Emphasis is placed on comparisons recommended by test publishers and a discussion of minimum requirements for interpretation of differences scores is provided.  相似文献   
150.
Majority opinions are often observed in the process of social interaction in online communities, but few studies have addressed this issue with empirical data. To identify an appropriate theoretical lens for explaining majority opinions in online environments, this study investigates the skewness statistic, which indicates how many “Likes” are skewed to major comments on a Facebook post; 3489 posts are gathered from the New York Times Facebook page for 100 days. Results show that time is not an influential factor for skewness increase, but the number of comments has a logarithmic relation to skewness increase. Regression models and Chow tests show that this relationship differs depending on topic contents, but majority opinions are significant in overall. These results suggest that the bandwagon effect due to social affordance can be a suitable mechanism for explaining majority opinion formation in an online environment and that majority opinions in online communities can be misperceived due to overestimation.  相似文献   
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