香港科技大学实验室安全管理系统

建立有效的实验室安全管理系统,需要校方提供多方面的配套,如行政、人事、技术、资源等支持.此外,各职别在安全管理的权责要清晰,安全指引要详尽及明确,各项安全服务要周详并有效率,系统效果要定期监察,并要持续改进,才能建立实验室安全文化.     

Specific muscle synergies in national elite female ice hockey players in response to unexpected external perturbation

This study aimed to investigate specific muscle synergies in elite ice hockey players indicating highly developed postural control strategies used to restore balance against unexpected external perturbations. Seven elite athletes (EA) on the women’s national ice hockey team and 7 non-athletes (NA) participated in this study. Based on trajectories of centre of mass (COM), analysis periods were divided into an initial phase (a balance disturbance after perturbation onset) and a reversal phase (a balance recovery response), respectively. Muscle synergies were extracted at each phase by using non-negative matrix factorization. k-means cluster analysis was performed to arrange similar muscle synergies in all participants. EA showed significantly shorter recovery period of COM and smaller body sway than NA. In the initial phase, we identified 2 EA-specific synergies related to ankle plantar flexors or neck extensors. In the case of an NA-specific synergy, co-activation of the ankle plantar flexors and dorsiflexors was found. In the reversal phase, no specific muscle synergies were identified. As the results, EA-specific muscle synergies showed low co-activation strategy of agonists and antagonists in ankle and neck extensors. Our results could provide critical information for rehabilitation strategies in athletes requiring high postural stability.     

Does Teaching Experience Matter? The Beliefs and Practices of Beginning and Experienced Physics Teachers

This study utilized multiple data sources to examine the beliefs about learning and teaching physics and the instructional practices of five beginning teachers and seven experienced teachers from Singapore. Our study was implemented in the unique context of teachers teaching the topic of electricity to students grouped according to academic abilities. The topic of electricity is one of the most difficult physics topics for students to understand and for teachers to teach. It was found that the experienced teachers, compared to the beginning teachers, tended to have beliefs about teaching and learning physics that are closer to constructivist views. The majority of the teachers, particularly the beginning teachers, espoused beliefs about learning physics that were incongruent with their beliefs about teaching physics. Although transmission-oriented and teacher-directed practices dominated the classroom lessons of both groups of teachers, more elements of constructivist instruction were found in the classroom lessons of the experienced teachers. It was also found that the classroom practices of the teachers, especially those in their inductive years of teaching, were more aligned with their beliefs about learning physics than their beliefs about teaching physics.     

Maternal literate mediation of writing and Korean children’s reading and writing across 1 year

The present study examined the relations of maternal literate support instructions during parent–child joint writing to children’s word reading and writing across 1 year among 95 4- and 5-year-old children from Korea. The whole episode of mothers individually teaching their children how to write words was videotaped, and a Korean scale of mothers’ literate mediation of their children’s writing was developed based on six cognitive strategies focusing on whole Gulja (Korean written syllable), visual strokes, letter, Gulja structure, and CV (consonant + vowel) and coda (final consonant of a syllable) subsyllabic units. Maternal literate support explained a significant amount of variance in children’s word reading and writing concurrently and longitudinally across 1 year after controlling for children’s age, nonverbal IQ, phonological and morphological awareness, rapid automatized naming and mother’s education. In addition, children’s coda phoneme awareness explained unique variance in word reading and writing concurrently and longitudinally. Results underscore the unique characteristics of Korean and the importance of Korean maternal literate support as a major factor in early literacy development.     

Perceived competence and autonomy as moderators of the effects of achievement goal orientations

The primary purpose of this study was to investigate the roles of two moderators – perceived competence and perceived autonomy – in the relationships of achievement goal orientations with a broad range of learning‐related variables, including interest, effort, learning strategy use and academic achievement. Perceived competence and autonomy played roles as moderators by strengthening the positive effects of a mastery goal pursuit on outcome measures of adaptive use of learning strategies and effort, respectively. However, no moderating role of either perceived competence or perceived autonomy was found for the effect of a performance‐approach and performance‐avoidance goal pursuit. In addition, perceived competence played a significant role in determining the level of academic achievement in the context of multiple‐goal pursuit. For students with high perceived competence, the adoption of high performance‐approach goals resulted in a higher level of achievement regardless of the levels of mastery goals. In contrast, students with low perceived competence showed the highest achievement when high performance‐approach goals are paired with low mastery goals.     

Peer reviewers learn from giving comments

Research on peer reviewing has revealed that comments received from peer reviewers are helpful when it comes to making revisions in an individual’s writing, but the role of providing comments to peer writers has been little explored despite the potential value of such research. In this study, we explored how student reviewers learn by reviewing peer drafts in the context of reciprocal peer reviewing. Undergraduate students in an introductory physics course participated in this study as part of their course activities. Participants wrote technical research drafts, reviewed three or four peer drafts, and revised their own drafts in the SWoRD system. A total of 3,889 comment segments were analyzed in two dimensions: (a) evaluation (strength vs. weakness) and (b) scope (surface, micro-meaning, and macro-meaning). We found that providing weakness comments for micro-meaning and strength comments for macro-meaning improved the reviewers’ writing qualities. In addition, reviewers’ initial writing skills and the quality of reviewed peer drafts influenced the types of comments given. The results are discussed, along with their implications for improved writing through reviewing.     

A semantic Bayesian network approach to retrieving information with intelligent conversational agents

As access to information becomes more intensive in society, a great deal of that information is becoming available through diverse channels. Accordingly, users require effective methods for accessing this information. Conversational agents can act as effective and familiar user interfaces. Although conversational agents can analyze the queries of users based on a static process, they cannot manage expressions that are more complex. In this paper, we propose a system that uses semantic Bayesian networks to infer the intentions of the user based on Bayesian networks and their semantic information. Since conversation often contains ambiguous expressions, the managing of context and uncertainty is necessary to support flexible conversational agents. The proposed method uses mixed-initiative interaction (MII) to obtain missing information and clarify spurious concepts in order to understand the intention of users correctly. We applied this to an information retrieval service for websites to verify the usefulness of the proposed method.     

Chaos and control of discrete dynamic traffic model

This study discusses chaotic traffic flow. The discrete dynamic model proposed herein is derived from both the flow-density-speed fundamental diagram and Greenshield's model. The model employs occupancy as its variable and the ratio of free flow and average speed as its control parameter. The function form of the model is equal to logistic map that bifurcates when the value of the control parameter increases. Chaotic traffic means that traffic becomes unstable and unpredictable, which is dangerous for driving. Therefore, this study considers the implementation of chaotic control in signal or ramp metering design so as to stabilize the chaotic traffic phenomena. These results are illustrated by numerical examples.     

Eliciting critical literacy narratives of bi/multilingual teacher candidates across U.S. teacher education contexts

This paper examines critical literacy narratives of bi/multilingual preservice teachers across contexts in the United States. It draws upon empirical data from two studies—a narrative inquiry with Latino teacher candidates in the Midwest and a participatory action research project with bilingual preservice teachers in Hawaii—to examine participants’ identities and experience in academia. Preservice teachers in both studies resisted the labeling practice of “minority” and challenged simplistic notions of “bilingual teacher identity.” This cross-examination argues for further ways to explore how teacher preparation programs should create dialogic spaces for making the voices of diverse preservice teachers heard.     

Iraqi Refugee High School Students’ Academic Adjustment

Many Iraqi refugee students in the United States suffer from posttraumatic stress disorder (PTSD) as well as acculturation stresses. These stresses often create challenges for their integration into U.S. schools. The project explored risk factors such as the length of educational gaps in transit, PTSD, and separation and marginalization acculturation, as well as protective factors such as resilience, self-esteem, and integration and assimilation. We conducted bivariate correlations and multiple regression to examine the relationship between factors and predicting school adjustment using variables among 100 Iraqi refugee high school students in the Detroit area. The results showed that the educational gaps (negatively), and assimilation and resilience (positively), are the strongest predictors for school adjustment. PTSD incurred by Iraqis as a result of events experienced before and during their migration from Iraq are related to their self-esteem and separation acculturation, while educational gaps are related to their marginalization as well as to their integration.