Academic and administrative support for distance learners

The named works discuss the process of completing a doctorate via distance education.

Spherical harmonics and distance transform for image representation and retrieval

In this paper, we have proposed a method for 2D image retrieval based on object shapes. The method relies on transforming the 2D images into 3D space based on distance transform. Spherical harmonics are obtained for the 3D data and used as descriptors for the underlying 2D images. The proposed method is compared against two existing methods which use spherical harmonics for shape based retrieval of images. MPEG-7 Still Images Content Set is used for performing experiments; this dataset consists of 3621 still images. Experimental results show that the performance of the proposed descriptors is significantly better than other methods in the same category.

Discriminating DDoS flows from flash crowds using information distance

Discriminating DDoS flooding attacks from flash crowds poses a tough challenge for the network security community. Because of the vulnerability of the original design of the Internet, attackers can easily mimic the patterns of legitimate network traffic to fly under the radar. The existing fingerprint or feature based algorithms are incapable to detect new attack strategies. In this paper, we aim to differentiate DDoS attack flows from flash crowds. We are motivated by the following fact: the attack flows are generated by the same prebuilt program (attack tools), however, flash crowds come from randomly distributed users all over the Internet. Therefore, the flow similarity among DDoS attack flows is much stronger than that among flash crowds. We employ abstract distance metrics, the Jeffrey distance, the Sibson distance, and the Hellinger distance to measure the similarity among flows to achieve our goal. We compared the three metrics and found that the Sibson distance is the most suitable one for our purpose. We apply our algorithm to the real datasets and the results indicate that the proposed algorithm can differentiate them with an accuracy around 65%.

The future of distance education : reformed, scrapped or recycled

A mass of under-educated people, an expanding population, major global crises and an expanding knowledge economy all combine to sustain a massive demand for basic, further, higher, continuing and lifelong education.This demand cannot be met solely in the world’s classrooms; even if there were enough classrooms, many people will be unwilling or unable to attend them to learn. In this sense, distance education is essential for the future, but the fluidity around educational terms and practices means that it is also quite possible that ‘distance education’—the term and its history—will be towed to the scrap yard for many of its useful parts to be recycled. This chapter considers three key elements of distance education—technology, students and educational institutions—and the educational possibilities that surround them by reflection on past and present changes. The future of distance education is intimately connected to broader social, economic and cultural changes. These changes are strongly influenced by the ‘disruptive’ technologies, demographic transformations in the nature of distance learners and the pressures of global techno-capitalism on educational institutions.

Race-day carbohydrate intakes of elite triathletes contesting olympic-distance triathlon events

The aim of this study was to investigate the prerace and during-race carbohydrate intakes of elite-level triathletes contesting draft-legal Olympic-distance triathlon (ODT) events. Self-reported prerace and during-race nutrition data were collected at 3 separate ODT events from 51 elite senior and under-23 triathletes. One hundred twenty-nine observations of food and fluid intake representing actual prerace (n = 62) and during-race (n = 67) nutrition practices from 36 male and 15 female triathletes were used in the final analysis of this study. Female triathletes consumed significantly more carbohydrate on the morning before race start when corrected for body mass and race start time than their male counterparts (p < .05). Male and female triathletes consumed 26% more energy (kJ/kg) and 24% more carbohydrate (g/kg) when commencing a race after midday (1:00-1:30 p.m.) than for a late morning (11:00-11:15 a.m.) race start. During the race, triathletes consumed less than 60 g of carbohydrate on 66% of occasions, with average total race intakes of 48 ± 25 and 49 ± 25 g carbohydrate for men and women, respectively. Given average race times of 1:57:07 hr and 2:08:12 hr, hourly carbohydrate intakes were ∼25 g and ∼23 g for men and women, respectively. Although most elite ODT triathletes consume sufficient carbohydrate to meet recommended prerace carbohydrate intake guidelines, during-race carbohydrate intakes varied considerably, with many failing to meet recommended levels.

Quality in flexible, online and distance education at Deakin University, Australia

This chapter presents an overview of the management of quality for flexible, online and distance education (off-campus education) at Deakin University in Australia. In 1974, Deakin University was established as a dual-mode institution educating large numbers of both on- and off-campus students. From its foundation it has increasingly sought to provide the same learning resources, equivalent learning experiences and parity of outcomes to students studying in all modes (Hay, Lowe, Gibb & Anderson, 2002). While this was the ideal on which Deakin was founded, in practice approaches differed across various schools and courses where in some areas integration was achieved through an open-campus model, while in others the tendency was towards separation of the modes of delivery by course. Deakin’s history can be characterised as moving from dual-mode approaches to educating its student cohorts, to a now well articulated, integrated and institution-wide approach to assuring and improving the quality of all modes of educational delivery for an extremely diverse and complex set of student cohorts. In this regard, it makes no particular distinction between these student groups in its policies, procedures and processes relating to educational matters.

Sliding distance, contact pressure and wear in sheet metal stamping

This paper directly examines the contact sliding distance experienced during a typical sheet metal stamping process-an area that has largely been neglected in the literature. A method to numerically quantify the sliding distance is proposed. The sliding distance predicted from this method, and the contact pressure obtained from numerical simulation, allow the recently identified time-dependent contact conditions on the die and blank surfaces to be completely characterized. Consequently, a new insight into the wear/galling that occurs at the die radius in sheet metal stamping is gained. The results show that the region close to zero degrees on the die radius is likely to experience the most wear, with the identified transient stage contributing to a large proportion of the total wear. Additionally, the region on the blank surface often observed to be heavily burnished - the die impact line - is estimated to experience the highest wear severity due to the transient contact conditions. The proposed method to numerically quantify the sliding contact conditions can be applied as a general approach to study any other two-body sliding contact situations.

e-learning through digital theatre : breaking down the tyranny of distance and limits of location

In this article, we report on a cross-disciplinary, cross-cultural digital exchange project between Australian Drama and Education students and Dutch English Language and Culture students, and examine the impact of the place-independent, technology-mediated communications and collaboration on their learning trajectories. The intensive, intercultural collaboration between the two groups of students resulted in a 50-minute group-devised, digital theatre play entitled Quarter Acre Dreaming. This play, performed through live interactive media by both Dutch and Australian students, traced the historical development of the Australian suburb, while integrating scenes of Dutch immigration into Australia. In the creative process, the students on either side of the globe interacted through Computer-Mediated Communication (CMC), and used videoconferencing and Skype for live rehearsals and discussions to advance their learning of English, their performance repertoire and cross-cultural understanding.

A predictive model of avian natal dispersal distance provides prior information for investigating response to landscape change

1. Informative Bayesian priors can improve the precision of estimates in ecological studies or estimate parameters for which little or no information is available. While Bayesian analyses are becoming more popular in ecology, the use of strongly informative priors remains rare, perhaps because examples of informative priors are not readily available in the published literature.
2. Dispersal distance is an important ecological parameter, but is difficult to measure and estimates are scarce. General models that provide informative prior estimates of dispersal distances will therefore be valuable.
3. Using a world-wide data set on birds, we develop a predictive model of median natal dispersal distance that includes body mass, wingspan, sex and feeding guild. This model predicts median dispersal distance well when using the fitted data and an independent test data set, explaining up to 53% of the variation.
4. Using this model, we predict a priori estimates of median dispersal distance for 57 woodland-dependent bird species in northern Victoria, Australia. These estimates are then used to investigate the relationship between dispersal ability and vulnerability to landscape-scale changes in habitat cover and fragmentation.
5. We find evidence that woodland bird species with poor predicted dispersal ability are more vulnerable to habitat fragmentation than those species with longer predicted dispersal distances, thus improving the understanding of this important phenomenon.
6. The value of constructing informative priors from existing information is also demonstrated. When used as informative priors for four example species, predicted dispersal distances reduced the 95% credible intervals of posterior estimates of dispersal distance by 8-19%. Further, should we have wished to collect information on avian dispersal distances and relate it to species' responses to habitat loss and fragmentation, data from 221 individuals across 57 species would have been required to obtain estimates with the same precision as those provided by the general model.

Long-distance delivery of bacterial virulence factors by Pseudomonas aeruginosa outer membrane vesicles

Bacteria use a variety of secreted virulence factors to manipulate host cells, thereby causing significant morbidity and mortality. We report a mechanism for the long-distance delivery of multiple bacterial virulence factors, simultaneously and directly into the host cell cytoplasm, thus obviating the need for direct interaction of the pathogen with the host cell to cause cytotoxicity. We show that outer membrane–derived vesicles (OMV) secreted by the opportunistic human pathogen Pseudomonas aeruginosa deliver multiple virulence factors, including b-lactamase, alkaline phosphatase, hemolytic phospholipase C, and Cif, directly into the host cytoplasm via fusion of OMV with lipid rafts in the host plasma membrane. These virulence factors enter the cytoplasm of the host cell via N-WASP–mediated actin trafficking, where they rapidly distribute to specific subcellular locations to affect host cell biology. We propose that secreted virulence factors are not released individually as naked proteins into the surrounding milieu where they may randomly contact the surface of the host cell, but instead bacterial derived OMV deliver multiple virulence factors simultaneously and directly into the host cell cytoplasm in a coordinated manner.