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51.
Current barriers hindering data-driven discoveries in deep-time Earth (DE) include: substantial volumes of DE data are not digitized; many DE databases do not adhere to FAIR (findable, accessible, interoperable and reusable) principles; we lack a systematic knowledge graph for DE; existing DE databases are geographically heterogeneous; a significant fraction of DE data is not in open-access formats; tailored tools are needed. These challenges motivate the Deep-Time Digital Earth (DDE) program initiated by the International Union of Geological Sciences and developed in cooperation with national geological surveys, professional associations, academic institutions and scientists around the world. DDE’s mission is to build on previous research to develop a systematic DE knowledge graph, a FAIR data infrastructure that links existing databases and makes dark data visible, and tailored tools for DE data, which are universally accessible. DDE aims to harmonize DE data, share global geoscience knowledge and facilitate data-driven discovery in the understanding of Earth''s evolution.  相似文献   
52.
This paper is the second of two parts and continues the conversation which had called for a shift in the conceptual focus of science education towards philosophy of education, with the requirement to develop a discipline-specific “philosophy” of science education. In Part I, conflicting conceptions of science literacy were identified with disparate “visions” tied to competing research programs as well as school-based curricular paradigms. The impasse in the goals of science education and thereto, the contending views of science literacy, were themselves associated with three underlying fundamental aims of education (knowledge-itself; personal development; socialization) which, it was argued, usually undercut the potential of each other. During periods of “crisis-talk” and throughout science educational history these three aims have repeatedly attempted to assert themselves. The inability of science education research to affect long-term change in classrooms was correlated not only to the failure to reach a consensus on the aims (due to competing programs and to the educational ideologies of their social groups), but especially to the failure of developing true educational theories (largely neglected since Hirst). Such theories, especially metatheories, could serve to reinforce science education’s growing sense of academic autonomy and independence from socio-economic demands. In Part II, I offer as a suggestion Egan’s cultural-linguistic theory as a metatheory to help resolve the impasse. I hope to make reformers familiar with his important ideas in general, and more specifically, to show how they can complement HPS rationales and reinforce the work of those researchers who have emphasized the value of narrative in learning science.  相似文献   
53.
Application of physiological methods, in particular electroencephalography (EEG), offers new and promising approaches to educational psychology research. EEG is identified as a physiological index that can serve as an online, continuous measure of cognitive load detecting subtle fluctuations in instantaneous load, which can help explain effects of instructional interventions when measures of overall cognitive load fail to reflect such differences in cognitive processing. This paper presents a review of seminal literature on the use of continuous EEG to measure cognitive load and describes two case studies on learning from hypertext and multimedia that employed EEG methodology to collect and analyze cognitive load data.  相似文献   
54.
Behavioral and neurophysiological effects of a computer-aided morphological training protocol were examined in German-speaking children from Grades 3 to 9. Study 1 compared morphological awareness, reading, and spelling skills of 34 trained children with an untrained control group of 34 children matched for age, sex, and intelligence. All participants in the training group showed increases in morphological awareness, but only students from secondary school improved significantly in reading and spelling competences. In Study 2, a subsample of 8 trained children with poor spelling and reading abilities and 10 untrained children with higher language competencies underwent an electroencephalography testing involving three different language tasks. The training resulted in decreased theta-activity and increased activity in lower (7–10 Hz) and upper alpha (10–13 Hz). These findings reflect more effortful and attention-demanding processing after the training and suggest that children with poor spelling and reading abilities use the acquired morphological knowledge in terms of a compensatory strategy.  相似文献   
55.
This paper aims to provide new insights to debates on group privacy, which can be seen as part of a social turn in privacy scholarship. Research is increasingly showing that the classic individualistic understanding of privacy is insufficient to capture new problems in algorithmic and online contexts. An understanding of privacy as an “interpersonal boundary-control process” (Altman, The environment and social behavior, Brooks and Cole, Monterey, 1975) framing privacy as a social practice necessary to sustain intimate relationships is gaining ground. In this debate, my research is focused on what I refer to as “self-determined groups” which can be defined as groups whose members consciously and willingly perceive themselves as being part of a communicative network. While much attention is given to new forms of algorithmically generated groups, current research on group privacy fails to account for the ways in which self-determined groups are affected by changes brought about by new information technologies. In an explorative case study on self-organized therapy groups, I show how these groups have developed their own approach to privacy protection, functioning on the basis of social practices followed by all participants. This informal approach was effective in pre-digital times, but online, privacy threats have reached a new level extending beyond the scope of a group’s influence. I therefore argue that self-determined sensitive topic groups are left facing what I present as a dilemma: a tension between the seemingly irreconcilable need for connectivity and a low threshold, on the one hand, and the need for privacy and trust, on the other. In light of this dilemma, I argue that we need new sorts of political solutions.  相似文献   
56.
The primary aim of this study was to determine whether facial feature tracking reliably measures changes in facial movement across varying exercise intensities. Fifteen cyclists completed three, incremental intensity, cycling trials to exhaustion while their faces were recorded with video cameras. Facial feature tracking was found to be a moderately reliable measure of facial movement during incremental intensity cycling (intra-class correlation coefficient = 0.65–0.68). Facial movement (whole face (WF), upper face (UF), lower face (LF) and head movement (HM)) increased with exercise intensity, from lactate threshold one (LT1) until attainment of maximal aerobic power (MAP) (WF 3464 ± 3364mm, < 0.005; UF 1961 ± 1779mm, = 0.002; LF 1608 ± 1404mm, = 0.002; HM 849 ± 642mm, < 0.001). UF movement was greater than LF movement at all exercise intensities (UF minus LF at: LT1, 1048 ± 383mm; LT2, 1208 ± 611mm; MAP, 1401 ± 712mm; P < 0.001). Significant medium to large non-linear relationships were found between facial movement and power output (r2 = 0.24–0.31), HR (r2 = 0.26–0.33), [La?] (r2 = 0.33–0.44) and RPE (r2 = 0.38–0.45). The findings demonstrate the potential utility of facial feature tracking as a non-invasive, psychophysiological measure to potentially assess exercise intensity.  相似文献   
57.
The Digital Competency Profiler (DCP) is an online application for surveying the technology preferences and abilities of students in higher education. To explore the DCP as a digital-learning-readiness tool, a mixed-methods research design was developed for relating self-reported digital competencies and online-learning activity. To this end, three authentic scenarios, comprised of six tasks mapped to self-report items, were constructed. Having submitted their survey data, each of 15 participants visited the EILAB to complete a randomly-assigned scenario with a tablet. Both the performance activity and post-activity interviews were recorded digitally using a unique activity-station setup, and task artefacts were gathered as performance outcomes. Analysis was conducted in three phases. In Phase 1, both the audio-video performance data and activity artefacts were coded, assessed and scored. Exploratory correlational analyses showed a pattern of positive relationships at the task and scenario levels for two scenario groups, suggesting some predictive value for the DCP in this context. For the third group, a positive correlation was found at the scenario level, but negative correlations were found at the task level. In Phase 2, detailed case-studies were conducted, incorporating self-report data, coded performance timelines, and post-activity interviews. Several situational influencers related to problem-solving strategy, device comfort, task difficulty and motivation, beyond the purview of the DCP, were identified. In Phase 3, the findings were interpreted to position the DCP as a tool for identifying segments of students with members who, without support, will likely struggle to engage fully in technology-rich learning environments.  相似文献   
58.
Abstract

The purpose of the present investigation was to examine the concurrent and construct validity of the three-mile (4.83 km) run as afield test of aerobic capacity. Subjects included 109 college-aged males whose three-mile run time (M = 1310.31 ± 184.48 s) was measured. Fifty of the subjects were given a maximal treadmill stress test, and their peak oxygen consumption (VO2peak) (M = 54.23 ± 7.08 ml.kg?1.min?1) was measured. The three-mile run was conducted on an outdoor 0.25 mile (0.425 km) track, and split tunes were recorded each 110 yds (100.32 m) for the first and last laps and total time was recorded for laps 2 through 11. The correlation coefficient between the run time and VO2peak was -.58, indicating only moderate concurrent validity for the run as afield test for aerobic capacity. A factor analysis conducted on the split time data revealed a three-factor structure of a stable pace phase, an initial sprint, and a final sprint with the stable pace factor accounting for most of the common factor variance (69%). The three-mile run time was used to discriminate successfully between two known groups of subjects in aerobic capacity. These data provide a degree of support for the construct validity of the three-mile run as afield test of aerobic capacity.  相似文献   
59.
Abstract

The purpose of this study was to compare one-repetition maximum (1-RM) and muscle activity in three chest-press exercises with different stability requirements (Smith machine, barbell, and dumbbells). Twelve healthy, resistance-trained males (age 22.7 ± 1.7 years, body mass 78.6 ± 7.6 kg, stature 1.80 ± 0.06 m) were tested for 1-RM of the three chest-press exercises in counterbalanced order with 3–5 days of rest between the exercises. One-repetition maximum and electromyographic activity of the pectoralis major, deltoid anterior, biceps, and triceps brachii were recorded in the exercises. The dumbbell load was 14% less than that for the Smith machine (P ≤ 0.001, effect size [ES] = 1.05) and 17% less than that for the barbell (P ≤ 0.001, ES = 1.11). The barbell load was ~3% higher than that for the Smith machine (P = 0.016, ES = 0.18). Electrical activity in the pectoralis major and anterior deltoid did not differ during the lifts. Electrical activity in the biceps brachii increased with stability requirements (i.e. Smith machine <barbell <dumbbells; P ≤ 0.005; ES = 0.57, 1.46, and 2.00, respectively), while triceps brachii activity was reduced using dumbbells versus barbell (P = 0.007, ES = 0.73) and dumbbells versus Smith machine (P = 0.003, ES = 0.62). In conclusion, high stability requirements in the chest press (dumbbells) result in similar (pectoralis major and anterior deltoid), lower (triceps brachii) or higher (biceps brachii) muscle activity. These findings have implications for athletic training and rehabilitation.  相似文献   
60.
Abstract

Tridimensional angular displacements of the skates were determined with a single cinecamera used in conjunction with two orthogonal rods attached to the rear part of the skater's boots. The method was based on the commutative law with the imposed restrictions that two of the angles were small in relation to the other one, and that a sequence of angular displacements was defined. This approach required the sole determinations of the planar coordinates of the three points delimiting the orthogonal rods. An experimental setup was designed to validate the method: the criterion angles were approximated with less than 2 degrees of error. Subsequently, the method was applied to a practical situation: the two-legged stop in ice hockey. The combination of this tridimensional method with instrumented strain gauge skates for the measurement of forces provides a new and powerful tool for performing kinetic analyses in tridimensional skating activities.  相似文献   
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