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11.
Previous papers on grey literature by the authors have described (1) the need for formal metadata to allow machine understanding
and therefore scalable operations; (2) the enhancement of repositories of grey (and other) e-publications by linking with
CRIS (Current Research Information Systems); (3) the use of the research process to collect metadata incrementally reducing
the threshold barrier for end-users and improving quality in an ambient GRIDs environment. This paper takes the development
one step further and proposes “intelligent” grey objects. The hypothesis is in 2 parts: (1) that the use of passive catalogs
of metadata does not scale (a) in a highly distributed environment with millions of nodes and (b) with vastly increased volumes
of R&D output grey publications with associated metadata; (2) that a new paradigm is required that (a) integrates grey with
white literature and other R&D outputs such as software, data, products and patents (b) in a self-managing, self-optimizing
way and that this paradigm manages automatically curation, provenance digital rights, trust, security and privacy. Concerning
(1) existing repositories provide catalogs; harvesting takes increasing time ensuring non-currency. The end-user expends much
manual effort/intelligence to utilize the results. The elapsed time of (1) the network (2) the centralized (or centrally controlled
distributed) catalog server searches (3) end-user intervention becomes unacceptable. Concerning (2) there is no paradigm currently
known to the authors that satisfies the requirement. Our proposal is outlined below. Hyperactive combines both hyperlinking
and active properties of a (grey) object. Hyperlinking implies multimedia components linked to form the object and also external
links to other resources. The term active implies that objects do not lie passively in a repository to be retrieved by end-users.
They “get a life” and the object moves through the network knowing where it is going. A hyperactive grey object is wrapped
by its (incrementally recorded) formal metadata and an associated (software) agent. It moves through process steps such as
initial concept, authoring, reviewing and depositing in a repository. The workflow is based on the rules and information in
the corporate data repository with which the agent interacts. Once the object is deposited, the agent associated with it actively
pushes the object to the end-users (or systems) whose metadata indicate interest or an obligation in a workflowed process.
The agents check the object and user (or system) metadata for rights, privacy, security parameters, and for any charges and
assure compatibility. Alternatively the object can be found passively by end-user or system agents. The object can also associate
itself with other objects forming relationships utilising metadata or content. Declared relationships include references and
citations; workflowed relationships include versions and also links to corporate information and research datasets and software;
inferenced relationships are discovered relationships such as between documents by different authors developed from an earlier
idea of a third author. Components of this paradigm have been implemented to some extent. The challenge is implementing—respecting
part two of the hypothesis—the integration architecture. This surely is harnessing the power of grey.
相似文献
Anne AssersonEmail: |
12.
The understanding and use of historical concepts specified in national history standards pose many challenges to students. These challenges include both the acquisition of content knowledge and the use of that knowledge in ways that require higher order thinking. All students, including adolescents with learning disabilities (LD), are expected to understand and use concepts of history to pass high-stakes assessments and to participate meaningfully in a democratic society. This article describes Content Enhancement Routines (CERs) to illustrate instructional planning, teaching, and assessing for higher order thinking with examples from an American history unit. Research on the individual components of Content Enhancement Routines will be illustrated with data from 1 of the routines. The potential use of integrated sets of materials and procedures across grade levels and content areas will be discussed. 相似文献
13.
Research in Science Education - This study examines science interests, efficacy, attitudes, and identity—referred to as affinities, in the context of an informal science outreach program for... 相似文献
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16.
Kosuke Tamura Jeffrey S. Wilson Keith Goldfeld Robin C. Puett David B. Klenosky William A. Harper 《Research quarterly for exercise and sport》2013,84(3):395-402
ABSTRACTPurpose: Most built environment studies have quantified characteristics of the areas around participants’ homes. However, the environmental exposures for physical activity (PA) are spatially dynamic rather than static. Thus, merged accelerometer and global positioning system (GPS) data were utilized to estimate associations between the built environment and PA among adults. Methods: Participants (N = 142) were recruited on trails in Massachusetts and wore an accelerometer and GPS unit for 1–4 days. Two binary outcomes were created: moderate-to-vigorous PA (MVPA vs. light PA-to-sedentary); and light-to-vigorous PA (LVPA vs. sedentary). Five built environment variables were created within 50-meter buffers around GPS points: population density, street density, land use mix (LUM), greenness, and walkability index. Generalized linear mixed models were fit to examine associations between environmental variables and both outcomes, adjusting for demographic covariates. Results: Overall, in the fully adjusted models, greenness was positively associated with MVPA and LVPA (odds ratios [ORs] = 1.15, 95% confidence interval [CI] = 1.03, 1.30 and 1.25, 95% CI = 1.12, 1.41, respectively). In contrast, street density and LUM were negatively associated with MVPA (ORs = 0.69, 95% CI = 0.67, 0.71 and 0.87, 95% CI = 0.78, 0.97, respectively) and LVPA (ORs = 0.79, 95% CI = 0.77, 0.81 and 0.81, 95% CI = 0.74, 0.90, respectively). Negative associations of population density and walkability with both outcomes reached statistical significance, yet the effect sizes were small. Conclusions: Concurrent monitoring of activity with accelerometers and GPS units allowed us to investigate relationships between objectively measured built environment around GPS points and minute-by-minute PA. Negative relationships between street density and LUM and PA contrast evidence from most built environment studies in adults. However, direct comparisons should be made with caution since most previous studies have focused on spatially fixed buffers around home locations, rather than the precise locations where PA occurs. 相似文献
17.
Keith?KoenigEmail author Nan?Davis?Mitchell Thomas?E.?Hannigan J.?Keith?Clutter 《Sports Engineering》2004,7(2):105-117
The speed at which a player can swing a bat is central to the games of baseball and softball, determining, to a large extent,
the hit speed of the ball. Experimental and analytical studies of bat swing speed were conducted with particular emphasis
on the influence of bat moment of inertia on swing speed. Two distinct sets of experiments measured the swing speed of colege
baseball and fast-pitch softball players using weighted rods and modified bats. The swing targets included flexible targets,
balls on a tee and machine pitched balls. Internal mass alterations provided a range of inertial properties. The average measured
speeds, from 22 to 31 m s−1, are consistent with previous studies. Bat speed approximately correlates with the moment of inertia of the bat about a vertical
axis of rotation through the batter's body, the speed generally decreasing as this moment of inertia increases. The analytical
model assumes pure rotation of the batter/bat system about a vertical axis through the batter's body. Aerodynamic drag of
the batter's arms and the bat is included in the model. The independent variable is bat moment of inertia about the rotation
axis. There is reasonable agreement between the model and the measured speeds. Detailed differences between the two suggest
the importance of additional degrees of freedom in determining swing speed. 相似文献
18.
The aims of this study were: (1) to identify the exercise intensity that corresponds to the maximal lactate steady state in adolescent endurance-trained runners; (2) to identify any differences between the sexes; and (3) to compare the maximal lactate steady state with commonly cited fixed blood lactate reference parameters. Sixteen boys and nine girls volunteered to participate in the study. They were first tested using a stepwise incremental treadmill protocol to establish the blood lactate profile and peak oxygen uptake ([Vdot]O2). Running speeds corresponding to fixed whole blood lactate concentrations of 2.0, 2.5 and 4.0?mmol?·?l?1 were calculated using linear interpolation. The maximal lactate steady state was determined from four separate 20-min constant-speed treadmill runs. The maximal lactate steady state was defined as the fastest running speed, to the nearest 0.5?km?·?h?1, where the change in blood lactate concentration between 10 and 20?min was?<0.5?mmol?·?l?1. Although the boys had to run faster than the girls to elicit the maximal lactate steady state (15.7 vs 14.3?km?·?h?1, P?<0.01), once the data were expressed relative to percent peak [Vdot]O2 (85 and 85%, respectively) and percent peak heart rate (92 and 94%, respectively), there were no differences between the sexes (P?>0.05). The running speed and percent peak [Vdot]O2 at the maximal lactate steady state were not different to those corresponding to the fixed blood lactate concentrations of 2.0 and 2.5?mmol?·?l?1 (P?>0.05), but were both lower than those at the 4.0?mmol?·?l?1 concentration (P?<0.05). In conclusion, the maximal lactate steady state corresponded to a similar relative exercise intensity as that reported in adult athletes. The running speed, percent peak [Vdot]O2 and percent peak heart rate at the maximal lactate steady state are approximated by the fixed blood lactate concentration of 2.5?mmol?·?l?1 measured during an incremental treadmill test in boys and girls. 相似文献
19.
Luís Vilar Ricardo Duarte Pedro Silva Jia Yi Chow Keith Davids 《Journal of sports sciences》2013,31(19):1751-1759
AbstractThis study examined the influence of pitch dimensions in small-sided soccer games in shaping opportunities for performers to maintain ball possession, pass to teammates and shoot at goal. Fifteen amateur standard male participants (M = 21.87, σ = 1.96 years) played 5 v 5 small-sided soccer games in three varying pitch conditions (28 m × 14 m, 40 m × 20 m and 52 m × 26 m). Thirty sequences of play in each condition were selected for digitisation using TACTO software, allowing the capture of bi-dimensional displacement coordinate data of all players and the ball. The values of interpersonal distance between all attackers and immediate defenders and the relative distances of defenders to intercept a shot and a pass were computed as dependent variables. Results showed existence of fewer opportunities to maintain ball possession on smaller pitches, compared to medium and larger pitches. Conversely, the different dimensions set to the pitch did not influence opportunities for players to shoot at goal, or to perform passes to other teammates. By examining the specific spatial–temporal relationships of players and key-task constraints, the data from this study explain how effects of manipulating pitch dimensions of small-sided games might enhance opportunities for acquiring specific movement and decision-making skills. 相似文献
20.
Hannele Forsman Arto Gråstén Minna Blomqvist Keith Davids Jarmo Liukkonen Niilo Konttinen 《Journal of sports sciences》2016,34(14):1319-1327
ABSTRACTThe objective of this study was to create a valid, self-reported, game-specific soccer competence scale. A structural model of perceived competence, performance measures and motivation was tested as the basis for the scale. A total of 1321 soccer players (261 females, 1060 males) ranging from 12 to 15 years (13.4 ± 1.0 years) participated in the study. They completed the Perceived Game-Specific Soccer Competence Scale (PGSSCS), self-assessments of tactical skills and motivation, as well as technical and speed and agility tests. Results of factor analyses, tests of internal consistency and correlations between PGSSCS subscales, performance measures and motivation supported the reliability and validity of the PGSSCS. The scale can be considered a suitable instrument to assess perceived game-specific competence among young soccer players. 相似文献