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31.
OBJECTIVE: This research examined the relative importance of icon characteristics in determining the speed and accuracy of icon identification. BACKGROUND: Studies to date have focused on the role of one or two icon characteristics when users first experience an icon set. This means that little is known about the relative importance of icon characteristics or how the role of icon characteristics might change as users gain experience with icons. METHODS: Thirty participants carried out an icon identification task over a long series of trials to simulate learning through experience. Icon characteristics investigated included semantic distance, concreteness, familiarity, and visual complexity. RESULTS: Icon characteristics were major determinants of performance, accounting for up to 69% of the variance observed in performance. However, the importance of icon characteristics changed with experience: Semantic distance is crucial initially while icon-function relationships are learned, but familiarity is important later because it has lasting effects on access to long-term memory representations. CONCLUSION: These findings suggest that icon concreteness may not be of primary importance when identifying icons and that semantic distance and familiarity may be more important. APPLICATION: Designers need to take into account icon characteristics other than concreteness when creating icons, particularly semantic distance and familiarity. The precise importance of the latter characteristics will vary depending on whether icons are rarely encountered or frequently used. 相似文献
32.
Dipl.-Wirtsch.-Ing Michael Klafft Dr. rer. pol. Sarah Spiekermann 《WIRTSCHAFTSINFORMATIK》2006,48(1):36-45
Web-based bid invitation platforms and reverse auctions are increasingly used by consumers for the procurement of goods and
services. An empirical examination shows that with B-2-C these procurement methods generate considerable benefits for the
consumer:
相似文献
– | ⊎ Reverse auctions and bid invitation platforms generate high consumer surplus in the procurement of general and crafts services. |
– | ⊎ The level of this consumer surplus is affected by the number of bidders. The duration of the auction and the starting price are less important. |
– | ⊎ In the painting business prices are considerably lower than with traditional procurement channels. |
– | ⊎ On bid invitation platforms, in most cases (> 55%) the bids with the lowest price are chosen. |
33.
This paper develops an approach to thinking about young children, digital technologies and learning, drawing on research literature that relates children’s learning to the use of books, and on literature that discusses the nature of interaction between adults and children and its relationship to children’s learning. An analysis is given of parents and children using devices marketed as supporting young children’s learning, identifying, within the interactions that take place, the adult’s conception of appropriate use, and showing how this influences the nature of adult–child interaction. The findings are then related to literature on social interaction and learning, and discussed in relation to the assumptions that underpin the design of the devices used. The paper suggests that the artefact can influence adult–child interaction via a conception of appropriate use, which relates to traditions or practices with which the adult is familiar but also to the design features of the artefact. It suggests that it may be time to rethink the design of technologies to support young children’s learning. 相似文献
34.
John J. A. Barry Marta M. C. G. Silva Sarah H. Cartmell Robert E. Guldberg Colin A. Scotchford Steven M. Howdle 《Journal of Materials Science》2006,41(13):4197-4204
Porous scaffold structures are used in tissue engineering to provide structural guidance for regenerating tissues. The use
of carbon dioxide (CO2) to create such scaffolds has received some attention in the past but many researchers believe that although CO2 processing of polymers can lead to porous scaffolds there is limited interconnectivity between the pores. In this study,
highly porous (greater than 85%) and well interconnected scaffolds were obtained in which the size, distribution and number
of pores could be controlled. This control was achieved by altering the rate of venting from polymer discs saturated with
CO2 under modest temperature and pressure. The polymer used is a blend of poly (ethyl methacrylate) and tetrahydrofurfuryl methacrylate
(PEMA/THFMA). This polymer system has shown promise for potential applications in cartilage repair. 相似文献
35.
Richard Ashley David Blackwood Nicki Souter Sarah Hendry Jim Moir Judith Dunkerley John Davies David Butler Andrew Cook Jim Conlin Martin Squibbs Andrew Britton Peter Goldie 《Canadian Metallurgical Quarterly》2005,131(2):206-215
The study presented is an example of the assessment of the relative sustainability of either option for disposal of domestic sanitary waste, either via the toilet or via the solid waste route. This required an evaluation of the total (social, economic, environmental, and technical) benefit/cost of implementing and adopting the alternative routes and an assessment of public responsiveness to encouragement to change sanitary waste disposal practices. It illustrates how, even for an apparently straightforward either/or question, the assessment of relative sustainability is complex and the amount of data needed to quantify sustainability indicators is prodigious. The study also provides an appraisal of the effectiveness of public campaigns to reduce waterborne disposal. Important information regarding public attitude and behavior in relation to wastewater systems has been acquired and lessons for ways of encouraging behavioral change to more sustainable ways of living have been gleaned. 相似文献
36.
Heil Sarah H.; Sigmon Stacey C.; Mongeon Joan A.; Higgins Stephen T. 《Canadian Metallurgical Quarterly》2005,13(3):238
The present study was an experimental test of efficacy of a brief education intervention for increasing HIV/AIDS knowledge among cocaine-dependent outpatients. Participants were randomly assigned to an HIV/AIDS education intervention (experimental condition) or a sham intervention (control condition). Control participants were subsequently crossed over to the HIV/AIDS education intervention. Experimental participants had higher scores on tests of HIV/AIDS knowledge after receiving the education intervention than did control participants. Further supporting the intervention's efficacy, control participant scores also increased once participants were crossed over and received the education intervention. Scores at follow-up were lower than at postintervention but remained higher than baseline scores. Results support the intervention's efficacy for increasing HIV/AIDS knowledge among cocaine-dependent outpatients. This intervention is brief, inexpensive, and easily implemented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
A dynamic feedback controller design method is proposed for multiple input systems. The method uses a novel choice of sliding surface to effect asymptotic linearisation of nonlinear differential input output systems and a class of state space systems. The stability of the overall system, that is a canonical state space form with a dynamic feedback, is analysed with a generalised Lyapunov approach plus an asymptotic analysis in a neighbourhood of the origin. The nonlinear system does not have to be expressed in regular form as is the case in many other sliding mode control approaches. A type of zero dynamics, which are the dynamics of the control, are involved. The resulting dynamic feedback is shown to provide chatter free control if the system is minimum phase with respect to the zero dynamics. The theoretical results are applied to Gas Jet systems with two controls. 相似文献
38.
Miller Joshua D.; Reynolds Sarah K.; Pilkonis Paul A. 《Canadian Metallurgical Quarterly》2004,16(3):310
The authors examined the validity of D. R. Lynam and T. A. Widiger's (2001) prototypes for personality disorders (PDs) derived from the facets of the 5-factor model (FFM) of personality in 2 clinical samples. In the 1st sample (N = 94), there was good agreement between the prototypes generated by experts and the profiles reported by patients. These FFM PD similarity scores also demonstrated good convergent and discriminant validity with results from a semistructured interview and a self-report measure of Axis II pathology. In the 2nd sample (N = 132), the FFM PD similarity scores demonstrated excellent longitudinal stability and good predictive validity with regard to consensus ratings of PD features. The implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
39.
Sarah Gordon 《Network Security》2004,2004(6):17-18
Antivirus software tests are important when selecting antivirus software. However, there are many different tests, and interpreting the results can be challenging. Additionally, the needs of the corporate customer and home user differ, and it is important to understand these differences in order to evaluate antivirus software tests critically. 相似文献
40.
Mariana P. Pinho Guilherme A. Lepski Roberta Rehder Nadia E. Chauca-Torres Gabriela C. M. Evangelista Sarah F. Teixeira Elizabeth A. Flatow Jaqueline V. de Oliveira Carla S. Fogolin Nataly Peres Analía Arvalo Venncio Alves Jos A. M. Barbuto Patricia C. Bergami-Santos 《International journal of molecular sciences》2022,23(10)
Immunotherapy has brought hope to the fight against glioblastoma, but its efficacy remains unclear. We present the case of CST, a 25-year-old female patient with a large right-hemisphere glioblastoma treated with a dendritic–tumor cell fusion vaccine. CST showed a near-complete tumor response, with a marked improvement in her functional status and simultaneous increases in tumor-specific CD8+ and CD4+ T cells. Two months before recurrence, the frequency of tumor-specific T cells decreased, while that of IL-17 and CD4+ T cells increased. CST passed away 15 months after enrollment. In this illustrative case, the tumor-specific CD4+ T-cell numbers and phenotype behaved as treatment efficacy biomarkers, highlighting the key role of the latter in glioblastoma immunotherapy. 相似文献