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11.
Clusters and grids of workstations provide available resources for data mining processes. To exploit these resources, new distributed algorithms are necessary, particularly concerning the way to distribute data and to use this partition. We present a clustering algorithm dubbed Progressive Clustering that provides an “intelligent” distribution of data on grids. The usefulness of this algorithm is shown for several distributed datamining tasks. 相似文献
12.
A multiparameter wearable physiologic monitoring system for space and terrestrial applications. 总被引:4,自引:0,他引:4
Carsten W Mundt Kevin N Montgomery Usen E Udoh Valerie N Barker Guillaume C Thonier Arnaud M Tellier Robert D Ricks Robert B Darling Yvonne D Cagle Nathalie A Cabrol Stephen J Ruoss Judith L Swain John W Hines Gregory T A Kovacs 《IEEE transactions on information technology in biomedicine》2005,9(3):382-391
A novel, unobtrusive and wearable, multiparameter ambulatory physiologic monitoring system for space and terrestrial applications, termed LifeGuard, is presented. The core element is a wearable monitor, the crew physiologic observation device (CPOD), that provides the capability to continuously record two standard electrocardiogram leads, respiration rate via impedance plethysmography, heart rate, hemoglobin oxygen saturation, ambient or body temperature, three axes of acceleration, and blood pressure. These parameters can be digitally recorded with high fidelity over a 9-h period with precise time stamps and user-defined event markers. Data can be continuously streamed to a base station using a built-in Bluetooth RF link or stored in 32 MB of on-board flash memory and downloaded to a personal computer using a serial port. The device is powered by two AAA batteries. The design, laboratory, and field testing of the wearable monitors are described. 相似文献
13.
Valerie Shute Seyedahmad Rahimi Ginny Smith Fengfeng Ke Russell Almond Chih-Pu Dai Renata Kuba Zhichun Liu Xiaotong Yang Chen Sun 《Journal of Computer Assisted Learning》2021,37(1):127-141
In this study, we investigated the validity of a stealth assessment of physics understanding in an educational game, as well as the effectiveness of different game-level delivery methods and various in-game supports on learning. Using a game called Physics Playground, we randomly assigned 263 ninth- to eleventh-grade students into four groups: adaptive, linear, free choice and no-treatment control. Each condition had access to the same in-game learning supports during gameplay. Results showed that: (a) the stealth assessment estimates of physics understanding were valid—significantly correlating with the external physics test scores; (b) there was no significant effect of game-level delivery method on students' learning; and (c) physics animations were the most effective (among eight supports tested) in predicting both learning outcome and in-game performance (e.g. number of game levels solved). We included student enjoyment, gender and ethnicity in our analyses as moderators to further investigate the research questions. 相似文献
14.
Quinkal Isabelle; Davasse Valerie; Gaillard Jacques; Moulis Jean-Marc 《Protein engineering, design & selection : PEDS》1994,7(5):681-687
The widespread occurrence of Pro residues adjacent to Cys ligandsin the sequences of [4Fe-4S] electron transfer proteins hasnot yet found a functional basis. The two such Pro of Clostridiumpasteurianum 2[4Fe-4S] ferredoxin have been probed by site-directedmutagenesis. Any one of them, but not both simultaneously, canbe substituted without impairing the proper folding of the protein.The reduction potentials of the ferredoxin variants fall ina narrow range of <20 mV above the potential of the nativeprotein. The biological activities with C.pasteurianum hydrogenaseand pyruvate-ferredoxin oxidoreductase do not change significantly,except when Lys replaces Pro. In these cases, the data suggestthat the two clusters of 2[4Fe-4S] ferredoxin may not alwaysbe equivalent in the interaction with the redox partners. Destabilizationof the structure has been observed as the consequence of theProl9 or Pro48 substitutions. Using 2-D NMR, this effect hasbeen associated with perturbations of both the hydrogen bondnetwork and one amino acid side chain around the [4Fe-4S] clusters.Thus, the conserved Pro found in the binding motif of [4Fe-4S]clusters in proteins strongly stabilizes the active site butdoes not play an essential role in the mechanism of electrontransfer. 相似文献
15.
Valerie E. Lesk Syadiah Nor Wan Shamsuddin Elizabeth R. Walters Hassan Ugail 《Virtual Reality》2014,18(4):271-279
Early diagnosis of Alzheimer’s disease (AD) is essential if treatments are to be administered at an earlier point in time before neurons degenerate to a stage beyond repair. In order for early detection to occur tools used to detect the disorder must be sensitive to the earliest of cognitive impairments. Virtual reality technology offers opportunities to provide products which attempt to mimic daily life situations, as much as is possible, within the computational environment. This may be useful for the detection of cognitive difficulties. We develop a virtual simulation designed to assess visuospatial memory in order to investigate cognitive function in a group of healthy elderly participants and those with a mild cognitive impairment (MCI). Participants were required to guide themselves along a virtual path to reach a virtual destination which they were required to remember. The preliminary results indicate that this virtual simulation has the potential to be used for detection of early AD since significant correlations of scores on the virtual environment with existing neuropsychological tests were found. Furthermore, the test discriminated between healthy elderly participants and those with a MCI. 相似文献
16.
The development of the Quick Exposure Check (QEC) for assessing exposure to risk factors for work-related musculoskeletal disorders 总被引:1,自引:0,他引:1
This paper describes the development and evaluation of the Quick Exposure Check (QEC), which is an observational tool developed for Occupational Safety and Health (OSH) practitioners to assess exposure to risks for work-related musculoskeletal disorders and provide a basis for ergonomic interventions. The tool is based on epidemiological evidence and investigations of OSH practitioners' aptitudes for undertaking assessments. It has been tested, modified and validated using simulated and workplace tasks, in two phases of development, with participation of 206 practitioners. The QEC allows the four main body areas to be assessed and involves practitioners and workers in the assessment. Trials have determined its usability, intra- and inter-observer reliability, and validity which show it is applicable to a wide range of working activities. The tool focuses primarily on physical workplace factors, but also includes the evaluation of psychosocial factors. Tasks can normally be assessed within 10min. It has a scoring system, and exposure levels have been proposed to guide priorities for intervention. Subsequently it should be used to evaluate the effectiveness of any interventions made. The QEC can contribute to a holistic assessment of all the elements of a work system. 相似文献
17.
The relationship between video gameplay, video game genre preference, personality, and GPA was investigated in an online correlational study with university students. In addition to administering self-report measures of GPA and personality, we asked three different questions regarding styles of video gameplay. The first asked the average time spent playing video games per week (habitual players), the second asked the total time spent playing favorite video games (selective players), and the third asked the number of different video games played in a year (diverse players). Students who were medium in selective player style (spent 11-50 h) had significantly higher GPAs than students low on selective player style (spent 0-10 h). Students high on habitual playing style (7 or more hours a week) showed significantly lower levels of Conscientiousness compared to students low on habitual playing style (0-1 h a week). Students who were high on the diverse style (i.e., 7 or more games played a year) showed significantly higher Openness scores than students low on the diverse style (0-3 games a year). Finally, several notable relations were found between video game genre preference, GPA, and personality. Results are discussed in terms of the positive implications of video gameplay on academic performance. 相似文献
18.
It is believed that by adulthood, independent attachments to the mother and the father coalesce into a single state of mind with respect to attachment. If true, states of mind with respect to mothers and fathers should be concordant. Fifty-six young adults were administered two versions of the Adult Attachment Interview, each of which asked about their relationship with one parent. State of mind with respect to the father was significantly related to state of mind with respect to the mother, as were attachment styles regarding the two parents. Perceptions of attachment styles were not very related to corresponding states of mind but were related to inferred loving from a parent. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
19.
This paper begins by identifying the growth in female-headed households in Australia. Despite this increase, it is argued that females still lag males in terms of home ownership rates (HORs) with women in Australia facing similar ownership challenges as those experienced in the UK and the USA. In seeking to establish any dynamic change, the study analyses female home ownership rates in Australia for two points in time, 1998 and 2008. Logit models are used to predict HORs. The results indicate that factors such as household type, income and source of income have an impact on rates of ownership. The paper concludes that female-headed households in Australia show an increasing propensity to purchase which match, or even exceed, those of male-headed households. 相似文献