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排序方式: 共有328条查询结果,搜索用时 15 毫秒
11.
Gitte Lindgaard Gary Fernandes Cathy Dudek J. Brow 《Behaviour & Information Technology》2006,25(2):115-126
Three studies were conducted to ascertain how quickly people form an opinion about web page visual appeal. In the first study, participants twice rated the visual appeal of web homepages presented for 500 ms each. The second study replicated the first, but participants also rated each web page on seven specific design dimensions. Visual appeal was found to be closely related to most of these. Study 3 again replicated the 500 ms condition as well as adding a 50 ms condition using the same stimuli to determine whether the first impression may be interpreted as a 'mere exposure effect' (Zajonc 1980). Throughout, visual appeal ratings were highly correlated from one phase to the next as were the correlations between the 50 ms and 500 ms conditions. Thus, visual appeal can be assessed within 50 ms, suggesting that web designers have about 50 ms to make a good first impression. 相似文献
12.
Chen Edith; Hermann Cathy; Rodgers Denise; Oliver-Welker Tina; Strunk Robert C. 《Canadian Metallurgical Quarterly》2006,25(3):389
This study tested the relationship of anxiety and asthma severity to symptom perception. Eighty-six children diagnosed with mild or moderate asthma had symptom perception and pulmonary function measured throughout methacholine challenge (to induce bronchoconstriction). Higher trait anxiety was associated with heightened symptom perception (controlling for pulmonary function) at baseline. Greater asthma severity was associated with blunted symptom perception (controlling for pulmonary function) at the end of methacholine challenge and with a slower rate of increase in symptom perception across methacholine challenge. These results suggest that anxiety plays a role when children's symptoms are mild, whereas medical variables such as severity play a role in perception of changes in asthma symptomatology as bronchoconstriction worsens. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
Explored how older adults recall the traits they possessed at an earlier age. It was hypothesized that older adults' recollections would be related to their theories about aging. In Study 1, a group of older Ss provided their theories concerning how various traits change with age. Another group of older Ss rated their current status on these traits and recalled the status they possessed at a younger age. In addition, a group of younger adults rated their current status on the same traits. On traits theorized to increase with age, older Ss recalled themselves as possessing lower levels at an earlier age than the younger group reported possessing. On traits theorized to decrease with age, older Ss recalled themselves as possessing higher levels at an earlier age than the younger group reported possessing. Study 2 indicated that this effect is obtained regardless of trait positivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
14.
Using data from a study with prospective-cohorts design in which children who were physically abused, sexually abused, or neglected about 20 years ago were followed up along with a matched control group, accuracy of adult recollections of childhood physical abuse was assessed. Two hour in-person interviews were conducted in young adulthood with 1,196 of the original 1,575 participants. Two measures (including the Conflict Tactics Scale) were used to assess histories of childhood physical abuse. Results indicate good discriminant validity and predictive efficiency of the self-report measures, despite substantial underreporting by physically abused respondents. Tests of construct validity reveal shared method variance, with self-report measures predicting self-reported violence and official reports of physical abuse predicting arrests for violence. Findings are discussed in the context of other research on the accuracy of adult recollections of childhood experiences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
15.
Wild oysters (Crassostrea virginica) contained cholesterol, 24-methyl-cholesta-5, 22-dienol, 24-methylenecholesterol, 22-dehydrocholesterol, 24-methylcholesterol,
24-ethylcholesterol, 24-norcholesta-5, 22-dienol, 24-ethylcholesta-5, 22-dienol and fucosterol. The same species was cultivated
on a defined diet ofThalassiosira pseudonana andIsochrysis sp. The dietary algae were cultured and their sterol compositions were analyzed by gas chromatography and mass spectroscopy.T. pseudonana andIsochrysis sp. had 24-methylenecholesterol and 24-methyl-cholesta-5, 22-dienol as their major sterols. The sterol composition of the
cultivated oysters revealed the predominance of cholesterol (19%), 24-methyl-cholesta-5, 22-dienol (21%) and 24-methylenecholesterol
(46%). Therefore, oysters must be able to bioconvert phytosterols to cholesterol, concentrate dietary cholesterol, or synthesize
cholesterol de novo. 相似文献
16.
This study was designed to quantify the increased risk of road crash-related injury, which can be attributed to risk-taking behaviour. A case-control study was conducted to compare motor vehicle drivers (car and bike) who had been hospitalised for injuries following crashes with population-based controls. Cases were recruited prospectively over 12 months and controls were randomly selected from license holders (car and bike) living in the same geographical location as cases. A self-administered questionnaire was used to ascertain participants' driving behaviour, general risk-taking behaviour and selected demographic characteristics. After adjusting for demographic variables, number of years of driving and total distance driven per week, logistic regression analysis showed that a high risk acceptance was associated with an eight-fold increased risk of having a crash that resulted in serious injury (OR 7.8, 95% CI 4.2-15.8). The findings of this study support the suggestion that certain host factors increase the risk of crash-related serious injury. There would appear to be a reasonable argument for persisting with injury prevention programmes, which concentrate on host as well as environment risk factor reduction. 相似文献
17.
Simeon Keates Ray Adams Cathy Bodine Sara Czaja Wayne Gordon Peter Gregor Emily Hacker Vicki Hanson John Kemp Mark Laff Clayton Lewis Michael Pieper John Richards David Rose Anthony Savidis Greg Schultz Paul Snayd Shari Trewin Philip Varker 《Universal Access in the Information Society》2007,5(4):329-339
In October 2005, the IBM Human Ability and Accessibility Center and T.J. Watson Research Center hosted a symposium on “cognitive
and learning difficulties and how they affect access to IT systems”. The central premise of the symposium was the recognition
that cognitive and learning difficulties have a profound impact on a person’s ability to interact with information technology
(IT) systems, but that little support is currently being offered by those systems. By bringing together internationally renowned
experts from a variety of different, but complementary, research fields, the symposium aimed to provide a complete overview
of the issues related to this topic. This paper summarises the discussions and findings of the symposium. 相似文献
18.
Capital asset pricing model (CAPM) has become a fundamental tool in finance for assessing the cost of capital, risk management, portfolio diversification and other financial assets. It is generally believed that the market risks of the assets, often denoted by a beta coefficient, should change over time. In this paper, we model timevarying market betas in CAPM by a smooth transition regime switching CAPM with heteroscedasticity, which provides flexible nonlinear representation of market betas as well as flexible asymmetry and clustering in volatility. We also employ the quantile regression to investigate the nonlinear behavior in the market betas and volatility under various market conditions represented by different quantile levels. Parameter estimation is done by a Bayesian approach. Finally, we analyze some Dow Jones Industrial stocks to demonstrate our proposed models. The model selection method shows that the proposed smooth transition quantile CAPM?CGARCH model is strongly preferred over a sharp threshold transition and a symmetric CAPM?CGARCH model. 相似文献
19.
The aim of this article is to develop new patent indicators for evaluating technological innovation competitiveness between
companies. A novel indicator representing an industrial’s patent performance, Essential Patent Index (EPI), was developed
by incorporating information on who cited these patents and when these patents were cited, based on the assumption that both
contribute to meaningful quality assessment. By combining EPI and Chi’s well known Technological Strength (TS) indicator,
a second novel indicator Essential Technological Strength (ETS) was developed to represent the innovation competitiveness
of an individual company. In this study, patent performance of three high-tech industries in Taiwan were analyzed using ETS
as well as the traditional TS for comparison. Results from this analysis demonstrated that ETS provided better insights by
clearly verifying the latent influence of citations, reinforcing the impact of essential patents, and aggrandizing the differences
of innovation competitiveness between companies. 相似文献
20.
Christopher M. Gribble Graham Peter Matthews Giuliano M. Laudone Andrew Turner Cathy J. Ridgway Joachim Schoelkopf Patrick A.C. Gane 《Chemical engineering science》2011,(16):3701
We present fundamental and quantitative comparisons between the techniques of porometry (or flow permporometry), porosimetry, image analysis and void network modelling for seven types of filter, chosen to encompass the range of simple to complex void structure. They were metal, cellulose and glass fibre macro- and meso-porous filters of various types. The comparisons allow a general re-appraisal of the limitations of each technique for measuring void structures. Porometry is shown to give unrealistically narrow void size distributions, but the correct filtration characteristic when calibrated. Shielded mercury porosimetry can give the quaternary (sample-level anisotropic) characteristics of the void structure. The first derivative of a mercury porosimetry intrusion curve is shown to underestimate the large number of voids, but this error can be largely corrected by the use of a void network model. The model was also used to simulate the full filtration characteristic of each sample, which agreed with the manufacturer's filtration ratings. The model was validated through its correct a priori simulation of absolute gas permeabilities for track etch, cellulose nitrate and sintered powder filters. 相似文献