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101.
Anna Wong Nadine Marcus Paul Ayres Lee Smith Graham A. Cooper Fred Paas John Sweller 《Computers in human behavior》2009
Based on the assumption of a working memory processor devoted to human movement, cognitive load theory is used to explore some conditions under which animated instructions are hypothesised to be more effective for learning than equivalent static graphics. Using paper-folding tasks dealing with human movement, results from three experiments confirmed our hypothesis, indicating a superiority of animation over static graphics. These results are discussed in terms of a working memory processor that may be facilitated by our mirror-neuron system and may explain why animated instructional animations are superior to static graphics for cognitively based tasks that involve human movement. 相似文献
102.
The controlled dispersion of fluids, particularly biologically relevant solutions in micro-volumes, is of high practical interest
in biotechnology and medicine. Pharmaceutical test assays, for example, need a method for the fast and defined deposition
of fluid samples. Most current micro-dispensing methods, i.e. contact-based pin printing, have problems such as time delays,
limited dosing velocity, minimum volume or high interference that limit biological applications. Spraying techniques suffer
from a lack of reproducibility; a defined deposition of samples on targets is not possible. Here, we introduce a new method
for the parallel and spatially defined dispersion of many micro-volumes that overcomes disadvantages of common micro-dispensers.
The overall approach is that a fluid drop, produced by a droplet generator, falls on a free trajectory with a defined kinetic
energy, and is split by a masking unit placed perpendicular to the flight direction into at least two smaller droplets (Zimmermann
et al. in Method and device for dosing fluid media, WO/2002/102515, Germany, 2002). On the target, the resulting droplets form reproducible patterns, which are enlarged and scalable images of the grid pattern.
Possible applications for this method are non-contact cell patterning, cell encapsulation, cryopreservation and fast mixing
processes in micro-volumes. Here, we use this method for the direct and defined parallel positioning of cell suspensions on
specific substrates, which can be useful for test assays, tissue engineering and cryopreservation. 相似文献
103.
Previous research has identified user concerns about biometric authentication technology, but most of this research has been
conducted in European contexts. There is a lack of research that has investigated attitudes towards biometric technology in
other cultures. To address this issue, data from India, South Africa and the United Kingdom were collected and compared. Cross-cultural
attitudinal differences were seen, with Indian respondents viewing biometrics most positively while respondents from the United
Kingdom were the least likely to have a positive opinion about biometrics. Multiple barriers to the acceptance of biometric
technology were identified with data security and health and safety fears having the greatest overall impact on respondents’
attitudes towards biometrics. The results of this investigation are discussed with reference to Hofstede’s cultural dimensions
and theories of technology acceptance. It is argued that contextual issues specific to each country provide a better explanation
of the results than existing theories based on Hofstede’s model. We conclude that cultural differences have an impact on the
way biometric systems will be used and argue that these factors should be taken into account during the design and implementation
of biometric systems. 相似文献
104.
Theo Lynn Lisa van der Werff Graham Hunt Philip Healy 《Journal of Computer Information Systems》2016,56(3):185-193
The purpose of this research is to identify the potential information components of an online, real-time trust label, which is proposed as a communication mechanism to encourage trust in cloud service providers and cloud computing products. An online Delphi process was used with 28 cloud computing experts (including vendors, software providers, and legal and business representatives). The proposed label contains 81 information components, covering the cloud service provider (e.g. physical location, legal jurisdiction), the cloud service itself (e.g. data location, security, backup, certification), and a historical service-level summary (e.g. uptime data, support response times). The potential benefits of such a label to encourage trustworthiness perceptions and trust behaviors in the cloud computing environment are explored. Limitations of the study are highlighted, and further research studies are suggested to test the concept of the label and to refine the components of the label itself. 相似文献
105.
The personal lift-assist device and lifting technique: a principal component analysis 总被引:1,自引:0,他引:1
The personal lift-assist device (PLAD) is a non-motorised, on-body device that acts as an external force generator using the concept of stored elastic energy. In this study, the effect of the PLAD on the lifting kinematics of male and female lifters was investigated using principal component analysis. Joint kinematic data of 15 males and 15 females were collected using an opto-electronic system during a freestyle, symmetrical-lifting protocol with and without wearing the PLAD. Of the 31 Principal Components (PCs) retained in the models, eight scores were significantly different between the PLAD and no-PLAD conditions. There were no main effects for gender and no significant interactions. Results indicated that the PLAD similarly affected the lifting kinematics of males and females; demonstrating significantly less lumbar and thoracic flexion and significantly greater hip and ankle flexion when wearing the PLAD. These findings add to the body of work that suggest the PLAD may be a safe and effective ergonomic aid. STATEMENT OF RELEVANCE: The PLAD is an ergonomic aid that has been shown to be effective at reducing low back demands during manual materials handling tasks. This body of work establishes that the PLAD encourages safe lifting practices without adversely affecting lifting technique. 相似文献
106.
Genetic analysis of a breeding animal population involves determining the inheritance pattern of genotypes for multiple genetic markers across the individuals in the population pedigree structure. However, experimental pedigree genotype data invariably contains errors in both the pedigree structure and in the associated individual genotypes, introducing inconsistencies into the dataset, rendering them useless for further analysis. The resolution of these errors requires consideration of genotype inheritance patterns in the context of the pedigree structure. Existing pedigree visualisations are typically more suited to human pedigrees and are less suitable for large complex animal pedigrees which may exhibit cross generational inbreeding. Similarly, table‐based viewers of genotype marker data can highlight where errors become apparent but lack the functionality and interactive visual feedback to allow users to locate the origin of errors within the pedigree. In this paper, we detail a design study steered by biologists who work with pedigree data, and describe successive iterations through approaches and prototypes for viewing genotyping errors in the context of a displayed pedigree. We describe how each approach performs with real pedigree genotype data and why eventually we deemed them unsuitable. Finally, a novel prototype visualisation for pedigrees, which we term the ‘sandwich view’, is detailed and we demonstrate how the approach effectively communicates errors in the pedigree context, supporting the biologist in the error identification task. 相似文献
107.
Jeong Eun Min Matthew D. WhitesideFiona S.L. Brinkman Brad McNeneyJinko Graham 《Computational statistics & data analysis》2011,55(1):935-943
Orthologs are genes in different species that have diverged from a common ancestral gene after speciation. In contrast, paralogs are genes that have diverged after a gene duplication event. For many comparative analyses, it is of interest to identify orthologs with similar functions. Such orthologs tend to support species divergence (ssd-orthologs) in the sense that they have diverged only due to speciation, to the same relative degree as their species. However, due to incomplete sequencing or gene loss in a species, predicted orthologs can sometimes be paralogs or other non-ssd-orthologs. To increase the specificity of ssd-ortholog prediction, Fulton et al. [Fulton, D., Li, Y., Laird, M., Horsman, B., Roche, F., Brinkman, F., 2006. Improving the specificity of high-throughput ortholog prediction. BMC Bioinformatics 7 (1), 270] developed Ortholuge, a bioinformatics tool that identifies predicted orthologs with atypical genetic divergence. However, when the initial list of putative orthologs contains a non-negligible number of non-ssd-orthologs, the cut-off values that Ortholuge generates for orthology classification are difficult to interpret and can be too high, leading to decreased specificity of ssd-ortholog prediction. Therefore, we propose a complementary statistical approach to determining cut-off values. A benefit of the proposed approach is that it gives the user an estimated conditional probability that a predicted ortholog pair is unusually diverged. This enables the interpretation and selection of cut-off values based on a direct measure of the relative composition of ssd-orthologs versus non-ssd-orthologs. In a simulation comparison of the two approaches, we find that the statistical approach provides more stable cut-off values and improves the specificity of ssd-ortholog prediction for low-quality data sets of predicted orthologs. 相似文献
108.
There are now a variety of Web bots or spiders available to scour the Web to automatically gather information. Bots, sometimes called agents when they are instructed to perform particular searches, are useful in performing the time-consuming and repetitive searches required to gather comparison data or to find an elusive item. In some cases, agents can not only find information but can make a purchase or take another action based on the data they collect. Although bots are great for consumers, some Internet retailers hate them. Just as a brick and mortar store wants potential customers to walk in the door, Web retailers want potential customers to personally view their sites. Once there, consumers might purchase the initial products they were seeking and then see advertisements or buy accessories, upgrades, or unrelated additional items as well. Because bots can reduce or eliminate these possibilities, some Internet retailers are trying to stop them. It's one thing to be upset about bots, spiders, agents, and data miners, but it is quite another to put an end to the practice. It should come as no surprise that federal and state laws in the US do not expressly mention bots. Those seeking to challenge their use must resort to a variety of more generic laws, none of which fit very well 相似文献
109.
Emma Murphy Ravi Kuber Graham McAllister Philip Strain Wai Yu 《Universal Access in the Information Society》2008,7(1-2):79-91
In this paper, an empirical based study is described which has been conducted to gain a deeper understanding of the challenges faced by the visually impaired community when accessing the Web. The study, involving 30 blind and partially sighted computer users, has identified navigation strategies, perceptions of page layout and graphics using assistive devices such as screen readers. Analysis of the data has revealed that current assistive technologies impose navigational constraints and provide limited information on web page layout. Conveying additional spatial information could enhance the exploration process for visually impaired Internet users. It could also assist the process of collaboration between blind and sighted users when performing web-based tasks. The findings from the survey have informed the development of a non-visual interface, which uses the benefits of multimodal technologies to present spatial and navigational cues to the user. 相似文献
110.
David-A. Mendels Emmelyn M. Graham Steven W. Magennis Anita C. Jones François Mendels 《Microfluidics and nanofluidics》2008,5(5):603-617
The development and adoption of lab-on-a-chip and micro-TAS (total analysis system) techniques requires not only the solving
of design and manufacturing issues, but also the introduction of reliable and quantitative methods of analysis. In this work,
two complementary tools are applied to the study of thermal and solutal transport in liquids. The experimental determination
of the concentration of water in a water–methanol mixture and of the temperature of water in a microfluidic T-mixer are achieved
by means of fluorescence lifetime imaging microscopy (FLIM). The results are compared to those of finite volume simulations
based on tabulated properties and well-established correlations for the fluid properties. The good correlation between experimental
and modelled results demonstrate without ambiguity that (1) the T-mixer is an adiabatic system within the conditions, fluids
and flow rates used in this study, (2) buoyancy effects influence the mixing of liquids of different densities at moderate
flow rates (Reynolds number Re ≪ 10−2), and (3) the combination of FLIM and computational fluid dynamics has the potential to be used to measure the thermal and
solutal diffusion coefficients of fluids for a range of temperatures and concentrations in one single experiment. As such,
it represents a first step towards the full-field monitoring of both the extent and the kinetics of a chemical reaction.
相似文献
David-A. MendelsEmail: |