202 resultados para Fisher distance criterion

em Deakin Research Online - Australia


Relevância:

100.00% 100.00%

Publicador:

Resumo:

The noninvasive brain imaging modalities have provided us an extraordinary means for monitoring the working brain. Among these modalities, Electroencephalography (EEG) is the most widely used technique for measuring the brain signals under different tasks, due to its mobility, low cost, and high temporal resolution. In this paper we investigate the use of EEG signals in brain-computer interface (BCI) systems.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

To promote efficient clinical practice, interest has been growing in brief assessment scales to replace full-scale versions in some circumstances. In nonclinical populations, the Wechsler Abbreviated Scale of Intelligence (WASI) has substituted for the Wechsler Intelligence Scale for Children—Third Edition (WISC-III). Agreement between these scales remains untested in clinical populations. Twenty-five children, aged 6 to 15 years old were assessed. A correlational and within-participant design was used. These scales were significantly correlated. Despite a fourth edition of the WISC now available, WASI administration alone would at times appear to be a quick and valid estimate of IQ. Replication with the WISC-IV seems necessary to clarify the verbal/ performance distance criterion discrepancy and also the meaning of some variability between the scale and subtests.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In contrast to northern temperate environments, where day length and temperature changes are obvious proximate cues for movement to resource-rich breeding habitats, the cues for movement used by birds in an often resource-poor, stochastic environment are less obvious. We recorded long-distance movements of 23 Grey Teal Anas gracilis using satellite telemetry for up to 879 days and examined the relationship between those movements and environmental factors, such as heavy rainfall and flooding, at the destination site. We identified 32 long-distance [> 150 km) movements that met our criterion for minimally interrupted flight between origin and destination. Thirteen of these flights coincided with rainfall and/or flooding events up to 1050 km from the origin. However, some ducks moved without any clear beneficial conditions at the destination onto small wetlands in regions with little surface water. The data suggest that there are two types of long-distance movement - ranging and directed. These flights occurred over distances up to 1200 km across the arid inland. The rates and distances of movement suggest that long-distance movements of Grey Teal entail high energy costs as in waterfowl elsewhere. We conclude that the proximate controls of directIn contrast to northern temperate environments, where day length and temperature changes are obvious proximate cues for movement to resource-rich breeding habitats, the cues for movement used by birds in an often resource-poor, stochastic environment are less obvious. We recorded long-distance movements of 23 Grey Teal Anas gracilis using satellite telemetry for up to 879 days and examined the relationship between those movements and environmental factors, such as heavy rainfall and flooding, at the destination site. We identified 32 long-distance (> 150 km) movements that met our criterion for minimally interrupted flight between origin and destination. Thirteen of these flights coincided with rainfall and/or flooding events up to 1050 km from the origin. However, some ducks moved without any clear beneficial conditions at the destination onto small wetlands in regions with little surface water. The data suggest that there are two types of long-distance movement – ranging and directed. These flights occurred over distances up to 1200 km across the arid inland. The rates and distances of movement suggest that long-distance movements of Grey Teal entail high energy costs as in waterfowl elsewhere. We conclude that the proximate controls of directed movements need not be very different from those of their temperate counterparts.ed movements need not be very different from those of their temperate counterparts.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper reports on the development of an asynchronous learning  environment for the teaching of introductory macroeconomics to    approximately 200 distance education students. The research supports evidence in the current literature that computer mediated communication and in particular, collaborative learning, can make a positive difference to the educational experience of some students. These findings are based on both quantitative and qualitative data gained from student evaluations,  participation levels, staff interviews and an analysis of the online communication. The discussion centres on the extent of collaboration, the role of assessment, adaptation of curriculum and pedagogy and the students' attitudes to economics.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The impact of time since fire after two consecutive wildfires 44 years apart (1939 and 1983) within the same area, and the distance from the fire boundary «100 m or 500-2000 m), were investigated in relation to the distribution and abundance of arboreal marsupials in 1994. Arboreal marsupials were censused by stagwatching and spotlighting in two relatively young age classes of mountain ash (Eucalyptus regnans) dominated forest in the Central Highlands of Victoria. Five species of arboreal marsupial were detected, but only three were detected in sufficient numbers to determine habitat preferences. Petauroides volans (greater glider) was statistically more abundant in 1939 regrowth forests, while Trichosurus caninus (mountain brushtail possum) showed no significant preference for either age class of forest. All but one record of Gymnobelideus leadbeateri (Leadbeater's possum) came from young forest, though the effect of age-class was not statistically significant. Distance from fire boundary explained little or no variation in mammal distribution or abundance. While the actual number of hollow-bearing trees was similar in both age classes of forest, the long-term lifespan of hollow-bearing trees in more recently burnt forest is predicted to be lower than in unburnt or not recently burnt forest. Post-fire salvage logging following the 1983 wildfires appears to have reduced the number of hollow-bearing trees at sites burnt in 1983.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper draws on two studies which researched the use of online small group environments where collaborative learning is a central structure for learning. The establishment of social presence is facilitated through the socio-affective aspect of small group interaction which contributed to the effectiveness of learning online. Social presence, the ability of online learners to project themselves into a textual environment which has few visual or contextual cues, will be explored as an important element in facilitating effective online learning. The teacher's role in helping students project their online social presence and in establishing an environment for learning within the larger group computer conference will also be discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper presents a simple and relatively straightforward solution to the problems of equity in laboratory practical exposure between distance-education students and their traditional, on-campus, fellow cohort. This system has been implemented for the past five years in a university that is amongst the leaders in distance education delivery and has proved to be extremely successful and very well accepted by all students. While the intention was to allow distance education students easy access to the required laboratory practical content of the course, the solution found has proved to have many advantages for the on-campus students. Although this specific implementation is based upon microcontroller technology units in an engineering degree course, the methodology is easily transferable to other disciplines and courses.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Concern that the definition of refugee based on race, religion, nationality, membership of a particular social group or political opinion found in 1951 United Nations Convention relating to the Status of Refugees is unduly narrow and arbitrary and should be replaced by a definition reflecting the concept of deprivation and need.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

1. To develop a conservation management plan for a species, knowledge of its distribution and spatial arrangement of preferred habitat is essential. This is a difficult task, especially when the species of concern is in low   abundance. In south-western Victoria, Australia, populations of the rare rufous bristlebird Dasyornis broadbenti are threatened by fragmentation of suitable habitat. In order to improve the conservation status of this species, critical habitat requirements must be identified and a system of corridors must be established to link known populations. A predictive spatial model of rufous bristlebird habitat was developed in order to identify critical areas requiring preservation, such as corridors for dispersal.
2
. Habitat models generated using generalized linear modelling techniques can assist in delineating the specific habitat requirements of a species. Coupled with geographic information system (GIS) technology, these models can be extrapolated to produce maps displaying the spatial configuration of suitable habitat.
3
. Models were generated using logistic regression, with bristlebird presence or absence as the dependent variable and landscape variables, extracted from both GIS data layers and multispectral digital imagery, as the predictors. A multimodel inference approach based on Akaike’s information criterion was used and the resulting model was applied in a GIS to extrapolate predicted likelihood of occurrence across the entire area of concern. The predictive performance of the selected model was evaluated using the receiver operating characteristic (ROC) technique. A hierarchical partitioning protocol was used to identify the predictor variables most likely to influence variation in the dependent variable. Probability of species presence was used as an index of habitat suitability.
4
. Negative associations between rufous bristlebird presence and  increasing elevation, 'distance to cree', 'distance to coast' and sun index were evident, suggesting a preference for areas relatively low in altitude, in close proximity to the coastal fringe and drainage lines, and receiving less direct sunlight. A positive association with increasing habitat complexity also suggested that this species prefers areas containing high vertical density of vegetation.
5. The predictive performance of the selected model was shown to be high (area under the curve 0·97), indicating a good fit of the model to the data. Hierarchical partitioning analysis showed that all the variables considered had significant  independent contributions towards explaining the variation in the dependent variable. The proportion of the total study area that was predicted as suitable habitat for the rufous bristlebird (using probability of occurrence at a ≥0·5 level ) was 16%.
6
. Synthesis and applications. The spatial model clearly delineated areas predicted as highly suitable rufous bristlebird habitat, with evidence of potential corridors linking coastal and inland populations via gullies. Conservation of this species will depend on management actions that protect the critical habitats identified in the model. A multi-scale  approach to the modelling process is recommended whereby a spatially explicit model is first generated using landscape variables extracted from a GIS, and a second model at site level is developed using fine-scale habitat variables measured on the ground. Where there are constraints on the time and cost involved in measuring finer scale variables, the first step alone can be used for conservation planning.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Recently DTW (dynamic time warping) has been recognized as the most robust distance function to measure the similarity between two time series, and this fact has spawned a flurry of research on this topic. Most indexing methods proposed for DTW are based on the R-tree structure. Because of high dimensionality and loose lower bounds for time warping distance, the pruning power of these tree structures are quite weak, resulting in inefficient search. In this paper, we propose a dimensionality reduction method motivated by observations about the inherent character of each time series. A very compact index file is constructed. By scanning the index file, we can get a very small candidate set, so that the number of page access is dramatically reduced. We demonstrate the effectiveness of our approach on real and synthetic datasets.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article presents a history of distance education in Australia. Australia's large distances and widely distributed population has meant that distance education has been an important part of its history. From the earliest provision of schooling by mail through a series of correspondence schools, both state and federal governments have provided a sound infrastructure to support distance education. Innovative uses of technologies to provide communication and interaction and ease the isolation of distance have also been a feature of Australia's distance education history. The impact of this history is particularly relevant as the Internet and information and communication technologies are changing this field and making distance educators of all institutions and sectors.