836 research outputs found
Epigeic spiders of the pastures of northern Wielkopolska
The fauna of epigeic spiders (Araneae) occurring on three different types of pastures in northern Wielkopolska was analysed. Studies were conducted from May 1992 to October 1993. The 18,995 specimens collected were classified as belonging to 137 species and 17 families. The family Linyphiidae proved the richest in species while Lycosidae was the most abundantly in terms of number of specimens. Zoocenological analysis of spider communities showed their differentiation testifying to differences in the sites studied. The dominants were: 1) Osowo Stare (Site 1): Pardosa palustris, 2) Sycyn Dolny (Site 2): Xerolycosa miniata, P. palustris, Xysticus kochi, 3) Brqczewo (Site 3): Erigone dentipalpis, P. palustris. Seasonal changes of dominance of the species at each site were established. A comparison of changes of the species' dominances in the years 1992 and 1993 disclosed similar values of the individual dominance coefficient at the sites in Osowo Stare and Brqczewo. This result indicates the occurrence of the process of stabilization of these biocenoses and a tendency to equilibrium in the environment. The least stable proved to be the site at Sycyn Dolny. Analysis of the seasonal dynamics of epigeic spider communities was also made by determining the mean number of species at each site in the two years of study. The highest number of species was noted in spring. It is interesting to note the appearance of species which are rare or very rare in Poland such as: Lepthyphantes insignis, Ostearius melanopygius, Enoplogriatha mordax and Enoplognatha oelandica
The effects of cooperative and competitive games on classroom interaction frequencies
This research looks at the effects of playing cooperative and competitive computer games on pupils’ classroom interaction frequency, as an index of their cooperation and engagement in class. It was predicted that students who played a cooperative game would receive higher teacher ratings of classroom interaction frequency, whereas students who played a competitive game would receive lower teacher ratings of classroom interaction frequency. Thirty-two school children with behaviour and learning difficulties played either a cooperative or competitive version of the Wii for a week. The pre- and post-game classroom interaction scores were different for the cooperative and competitive game conditions in the predicted directions. The findings suggest that cooperative games may benefit the social interaction of pupils within the classroom
An analysis into early customer experiences of self-service checkouts:lessons for improved usability
The research aims to examine the perceptions of relative novice users of self-service checkouts (SSCOs) and if these perceptions change before, during and following use. Employing a diary approach with 31 respondents relatively unfamiliar with SSCOs, the research will document their experiences with this technology across stationary, hardware and grocery stores in two Scottish cities (Glasgow and Dundee). Findings suggest that the majority of respondents were motivated to use the technology because of time saving and convenience. However, the actual experience of using SSCOs was not always considered quicker when compared to staffed checkouts because of technical issues, lack of staff assistance and the impersonal, sometimes stressful and controlled nature of the cramped SSCO environment. Following post-use reflections, the majority of respondents’ opinions did not change from their initial perceptions and indicated that they would prefer not to use the technology in the future. Based on the findings, this study makes some practical suggestions centring on the design and usability of SSCOs, which may go some way to reducing customer dissatisfaction and frustration with the technology, especially from the perspective of new users of the technology
Clustering via kernel decomposition
Spectral clustering methods were proposed recently which rely on the eigenvalue decomposition of an affinity matrix. In this letter, the affinity matrix is created from the elements of a nonparametric density estimator and then decomposed to obtain posterior probabilities of class membership. Hyperparameters are selected using standard cross-validation methods
Keystroke dynamics in the pre-touchscreen era
Biometric authentication seeks to measure an individual’s unique physiological attributes for the purpose of identity verification. Conventionally, this task has been realized via analyses of fingerprints or signature iris patterns. However, whilst such methods effectively offer a superior security protocol compared with password-based approaches for example, their substantial infrastructure costs, and intrusive nature, make them undesirable and indeed impractical for many scenarios. An alternative approach seeks to develop similarly robust screening protocols through analysis of typing patterns, formally known as keystroke dynamics. Here, keystroke analysis methodologies can utilize multiple variables, and a range of mathematical techniques, in order to extract individuals’ typing signatures. Such variables may include measurement of the period between key presses, and/or releases, or even key-strike pressures. Statistical methods, neural networks, and fuzzy logic have often formed the basis for quantitative analysis on the data gathered, typically from conventional computer keyboards. Extension to more recent technologies such as numerical keypads and touch-screen devices is in its infancy, but obviously important as such devices grow in popularity. Here, we review the state of knowledge pertaining to authentication via conventional keyboards with a view toward indicating how this platform of knowledge can be exploited and extended into the newly emergent type-based technological contexts
Designing authentication with seniors in mind
Developers typically adopt perceived best practice, and in the case of authentication this means password security. However, given the wide range of technical solutions available and the diverse needs and limitations of older users, we suggest that the default adoption of electronic “username and password” authentication may not be 'best practice' or even good practice. This paper highlights some challenges faced by three seniors, each of whom has multiple age- related disabilities and concomitant life challenges. The result is that they cannot authenticate themselves when they need to access their devices and accounts. We conclude by suggesting a number of research directions calculated to address some of these challenges and promote inclusive design and allow for diverse user authentication
Infrared studies of supernova remnants with the IRAS
A comparative study of the infrared and X-ray fluxes and morphologies of supernova remnants (SNR) can yield valuable information on their evolution and on their interaction with the smbient interstellar medium (ISM)
The behavioural impact of a visually represented virtual assistant in a selfservice checkout context
Our research investigated whether the presence of an interface agent - or virtual assistant (VA) - in a self-service checkout context has behavioural effects on the transaction process during particular tasks. While many participants claimed to have not noticed a VA within the self-service interface, behaviour was still affected, i.e. fewer people made errors with the VA present than in the voice-only and control conditions. The results are explained as reflective of an unconscious observation of non-verbal cues exhibited by the VA. The results are discussed in relation to possible behavioural outcomes of VA presence.</p
eHealth and the Internet of Things
To respond to an ageing population, eHealth strategies offer significant opportunities in achieving a balanced and sustainable healthcare infrastructure. Advances in technology both at the sensor and device levels and in respect of information technology have opened up other possibilities and options. Of significance among these is what is increasingly referred to as the Internet of Things, the interconnection of physical devices to an information infrastructure. The paper therefore sets out to position the Internet of Things at the core of future developments in eHealt
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