Viscoelastic and mechano-sorptive studies applied to the conservation of historical violins: A case study of the Guarneri “del Gesù” violin (1743) known as the “Cannone”     

Marco Fioravanti  Giacomo Goli  Bruce Carlson 《Journal of Cultural Heritage》2013,14(4):297-303

To assess the possible effects of mechanical loading on the conservation of historical wooden musical instruments, a research project was carried out on the violin Guarneri “del Gesù” (1743), known as the “Cannone”. This paper refers to the results obtained by studying the deformations to which a violin is subjected after being tuned, with special attention to the viscous and mechano-sorptive behaviour (as in a concert environment for example). The amount of viscoelastic creep was quantified under normal tuning conditions, and the mechano-sorptive creep was quantified using a dead mass resulting in 55% of the elastic deformation obtained after tuning. The viscoelastic and mechano-sorptive deformations were clearly observed. These deformations were completely recovered once the violin was unloaded, demonstrating that this violin structure is appropriately dimensioned for the applied stresses.  相似文献   

Generating gene summaries from biomedical literature: A study of semi-structured summarization   总被引：3，自引：0，他引：3  

Xu Ling  Jing Jiang  Xin He  Qiaozhu Mei  Chengxiang Zhai  Bruce Schatz   《Information processing & management》2007,43(6):1777

Most knowledge accumulated through scientific discoveries in genomics and related biomedical disciplines is buried in the vast amount of biomedical literature. Since understanding gene regulations is fundamental to biomedical research, summarizing all the existing knowledge about a gene based on literature is highly desirable to help biologists digest the literature. In this paper, we present a study of methods for automatically generating gene summaries from biomedical literature. Unlike most existing work on automatic text summarization, in which the generated summary is often a list of extracted sentences, we propose to generate a semi-structured summary which consists of sentences covering specific semantic aspects of a gene. Such a semi-structured summary is more appropriate for describing genes and poses special challenges for automatic text summarization. We propose a two-stage approach to generate such a summary for a given gene – first retrieving articles about a gene and then extracting sentences for each specified semantic aspect. We address the issue of gene name variation in the first stage and propose several different methods for sentence extraction in the second stage. We evaluate the proposed methods using a test set with 20 genes. Experiment results show that the proposed methods can generate useful semi-structured gene summaries automatically from biomedical literature, and our proposed methods outperform general purpose summarization methods. Among all the proposed methods for sentence extraction, a probabilistic language modeling approach that models gene context performs the best.  相似文献   

Interpersonal behaviour styles of primary education teachers during science lessons     

Darrell Fisher  Perry den Brok  Bruce Waldrip  Jeffrey Dorman 《Learning Environments Research》2011,14(3):187-204

This study reports the first development in Australia of primary science teacher typologies of teacher–student interpersonal behaviour, which was measured by students’ perceptions using the Questionnaire on Teacher Interaction (QTI). Earlier work with the QTI in The Netherlands has revealed eight different interpersonal styles, which were later confirmed with an American sample of secondary-school teachers and which were similar to types found with Australian secondary-school science teachers. The present study investigated the extent to which typologies found in earlier studies also apply to primary teachers. A cluster analysis was used to determine Australian typologies and to compare these with earlier findings. Prior typologies could only be partially confirmed, and the found typology of six styles was able to explain variance in both student outcomes and perceptions of cultural elements of the learning environment.  相似文献   

Building the BIKE: Development and Testing of the Biotechnology Instrument for Knowledge Elicitation (BIKE)     

Stephen B. Witzig  Carina M. Rebello  Marcelle A. Siegel  Sharyn K. Freyermuth  Kemal Izci  Bruce McClure 《Research in Science Education》2014,44(5):675-698

Identifying students’ conceptual scientific understanding is difficult if the appropriate tools are not available for educators. Concept inventories have become a popular tool to assess student understanding; however, traditionally, they are multiple choice tests. International science education standard documents advocate that assessments should be reform based, contain diverse question types, and should align with instructional approaches. To date, no instrument of this type targeting student conceptions in biotechnology has been developed. We report here the development, testing, and validation of a 35-item Biotechnology Instrument for Knowledge Elicitation (BIKE) that includes a mix of question types. The BIKE was designed to elicit student thinking and a variety of conceptual understandings, as opposed to testing closed-ended responses. The design phase contained nine steps including a literature search for content, student interviews, a pilot test, as well as expert review. Data from 175 students over two semesters, including 16 student interviews and six expert reviewers (professors from six different institutions), were used to validate the instrument. Cronbach’s alpha on the pre/posttest was 0.664 and 0.668, respectively, indicating the BIKE has internal consistency. Cohen’s kappa for inter-rater reliability among the 6,525 total items was 0.684 indicating substantial agreement among scorers. Item analysis demonstrated that the items were challenging, there was discrimination among the individual items, and there was alignment with research-based design principles for construct validity. This study provides a reliable and valid conceptual understanding instrument in the understudied area of biotechnology.  相似文献   

Promoting early career teacher resilience: a framework for understanding and acting     

Bruce Johnson  Barry Down  Rosie Le Cornu  Judy Peters  Anna Sullivan  Jane Pearce 《Teachers and Teaching》2014,20(5):530-546

In this paper, we undertake a brief review of the ‘conventional’ research into the problems of early career teachers to create a juxtaposed position from which to launch an alternative approach based on resilience theory. We outline four reasons why a new contextualised, social theory of resilience has the potential to open up the field of research into the professional lives of teachers and to produce new insights into the social, cultural and political dynamics at work within and beyond schools. We then move from these theoretical considerations to explain how we used them in a recent Australian research project that examined the experiences of 60 graduate teachers during their first year of teaching. This work led to the development of a Framework of Conditions Supporting Early Career Teacher Resilience which we outline, promote and advocate as the basis for action to better sustain our graduate teachers in their first few years of teaching. Finally, we reflect on the value of our work so far and outline our practical plans to ‘mobilise’ this knowledge in ways that will make it available to a variety of audiences concerned with the welfare of this group of teachers.  相似文献   

Longitudinal Stability of Phonological and Surface Subtypes of Developmental Dyslexia     

Robin L. Peterson  Bruce F. Pennington  Richard K. Olson  Sally J. Wadsworth 《Scientific Studies of Reading》2014,18(5):347-362

Limited evidence supports the external validity of the distinction between developmental phonological and surface dyslexia. We previously identified children ages 8 to 13 meeting criteria for these subtypes (Peterson, Pennington, & Olson, 2013) and now report on their reading and related skills approximately 5 years later. Longitudinal stability of subtype membership was fair and appeared stronger for phonological than surface dyslexia. Phonological dyslexia was associated with a pronounced phonological awareness deficit, but subgroups otherwise had similar cognitive profiles. Subtype did not inform prognosis. Results provide modest evidence for the validity of the distinction, although not for its clinical utility.  相似文献   

Student perceptions of personalised learning: development and validation of a questionnaire with regional secondary students     

Bruce Waldrip  Peter Cox  Craig Deed  Jeffrey Dorman  Debra Edwards  Cathleen Farrelly  Mary Keeffe  Valeria Lovejoy  Lucy Mow  Vaughan Prain  Peter Sellings  Zali Yager 《Learning Environments Research》2014,17(3):355-370

This project sought to evaluate regional students’ perceptions of their readiness to learn, assessment processes, engagement, extent to which their learning is personalised and to relate these to academic efficacy, academic achievement, and student well-being. It also examined teachers’ perceptions of students’ readiness to learn, the assessment process, engagement, and the extent to which students’ learning is personalised. The sample involved students in years 7–10 from six Victorian secondary schools. An instrument Personalised Learning Environment Questionnaire (PLQ) was developed to measure students’ perceptions of the factors effecting the implementation of Personalised Learning Plans (PLPs). It employed the latest scales to assess a range of PLP indicator variables, with all scales modified for use in an Australian context, and the total number of items kept to a minimum. Only scales more sensitive to PLPs were used to minimise the length of the instrument. There were three outcome variables: academic efficacy, academic achievement, and student well-being. The PLPs were assessed through scales that assess several contributing, distinct dimensions: selfdirected learning readiness, personal achievement, goal orientation, learning environment, personalised teaching and learning initiatives, curriculum entitlement and choice, and perceptions of assessment for learning. The trail PLQ was administered to 220 students, resulting in a 19 scale questionnaire with three or four items per scale. This paper reveals good data to model fit for the majority of items and each scale had good reliability. The paper describes the analytic techniques and results, how the instrument was refined and identifies common and uncommon student perceptions based on a post hoc analysis. The main study consisted of 2,407 students from four schools in the Bendigo Education Plan. They responded to this refined 19 scale version of the PLQ that was developed from the trial PLQ. All scales had satisfactory internal consistency reliability.  相似文献   

Cricket     

Marc R. Portus  Bruce R. Mason  Bruce C. Elliott  Max C. Pfitzner  Richard P. Done 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(2):263-284

In this study we analysed technique, ball speed and trunk injury data collected at the Australian Institute of Sport (AIS) from 42 high performance male fast bowlers over a four year period. We found several notable technique interrelationships, technique and ball speed relationships, and associations between technique and trunk injuries. A more front‐on shoulder alignment at back foot contact was significantly related to increased shoulder counter‐rotation (p < 0.001). Bowlers who released the ball at greater speeds had an extended front knee, or extended their front knee, during the front foot contact phase (p < 0.05). They also recorded higher braking and vertical impact forces during the front foot contact phase and developed those forces more rapidly (p ≤ 0.05). A maximum hip‐shoulder separation angle occurring later in the delivery stride (p = 0.05) and a larger shoulder rotation to ball release (p = 0.05) were also characteristics of faster bowlers. Bowlers suffering lower back injuries exhibited typical characteristics of the ‘mixed’ technique. Specifically, the hip to shoulder separation angle at back foot contact was greater in bowlers who reported soft tissue injuries than in non trunk‐injured bowlers (p = 0.03), and shoulder counter‐rotation was significantly higher in bowlers who reported lumbar spine stress fractures than non trunk‐injured bowlers (p = 0.01). The stress fracture group was also characterised by a larger hip angle at front foot contact and ball release, whereas a more flexed front knee at ball release characterised the non trunk‐injured group.  相似文献   

The influence of club-head kinematics on early ball flight characteristics in the golf drive     

Matthew Sweeney  Peter Mills  Jacqueline Alderson  Bruce Elliott 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(3):247-258

Despite many coaching and biomechanical texts describing how the kinematics of the club-head at impact lead to distance and accuracy of the ball flight, there is limited quantitative evidence supporting these assertions. The purpose of this study was to quantify the relationships between club-head kinematics and subsequent early ball flight characteristics during the golf drive. An opto-reflective system operating at 400 Hz was used to capture the swings of 21 male golfers using their own drivers. The 3D displacement data permitted the calculation of club-head kinematics at impact, as well as subsequent early ball flight characteristics. Using regression analyses, club-head kinematics at impact (velocity, orientation, path, and centeredness) were used to explain the variability in five dependent variables of early ball flight characteristics (resultant velocity, launch angle, side angle, back spin, and side spin). The results of the study indicated that club-head kinematics at impact explained a significant proportion of early ball flight characteristics (adjusted r ² = 0.71–0.82), even when generalized across individual clubs.  相似文献   

Effect of skill decomposition on racket and ball kinematics of the elite junior tennis serve     

Machar Reid  Bruce Elliott 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(4):296-303

Whole body kinematics of the tennis serve have been reported extensively in the literature, yet comparatively less information exists regarding the kinematic characteristics of the swing and toss. In attempting to develop consistency in placement of the toss and racket trajectory, coaches will often decompose the serve and practice it in separate parts. A 22-camera VICON MX motion analysis system, operating at 250 Hz, captured racket, ball and hand kinematics of the serves of five elite junior players under three conditions. The conditions were flat first serves (FS) directed to a 1 × 1 m target bordering the ‘T’ of the deuce service box, a ball toss (BT) in isolation and a free swing (SW) in isolation. Players were instructed to perform BT and SW as in the FS. Paired t-tests assessed within-group differences in hand, racket and ball kinematics between the discrete skill and the two decomposed conditions. Vertical displacement of the ball at its zenith increased significantly during BT compared with the FS and temporal associations between racket and ball motion during the FS (r = 0.861) were affected during task decomposition. This study questions the pervasive use of task decomposition in the development of the tennis serve.  相似文献