Document clustering evaluation : Divergence from a random baseline

Divergence from a random baseline is a technique for the evaluation of document clustering. It ensures cluster quality measures are performing work that prevents ineffective clusterings from giving high scores to clusterings that provide no useful result. These concepts are defined and analysed using intrinsic and extrinsic approaches to the evaluation of document cluster quality. This includes the classical clusters to categories approach and a novel approach that uses ad hoc information retrieval. The divergence from a random baseline approach is able to differentiate ineffective clusterings encountered in the INEX XML Mining track. It also appears to perform a normalisation similar to the Normalised Mutual Information (NMI) measure but it can be applied to any measure of cluster quality. When it is applied to the intrinsic measure of distortion as measured by RMSE, subtraction from a random baseline provides a clear optimum that is not apparent otherwise. This approach can be applied to any clustering evaluation. This paper describes its use in the context of document clustering evaluation.

Emergent innovation through the co-evolution of informal and formal media economies

Well-established distinctions between amateur and professional are blurring as the impact of social media, changes in cultural consumption, and crises in copyright industries’ business models are felt across society and economy. I call this the increasingly rapid co-evolution of the formal market and informal household sectors and analyse it through the concept of ‘social network markets’ – individual choices are made on the basis of other’s choices and such networked preferencing is enhanced by the growing ubiquity of social media platforms. This may allow us better to understand sources of disruption and innovation in audiovisual production and distribution in wealthy Western markets which are as significant as those posed by informal practices outside the West. I examine what is happening around the monetization and professionalization of online video (YouTube, for example) and the socialization of professional production strategies (transmedia, for example) as innovation from the margins.

Navigating the muddy waters of the research into single sex classrooms in co-educational middle years settings

Establishing single sex classes within co-educational sites is an option that Australian schools are again exploring. To date Australia has experienced three ‘waves’ of interest in establishing single sex classes, the first focused on equitable education opportunities for girls (Alloway & Gilbert, 1997), the second centered on boys’ literacy and engagement (Gilbert & Gilbert, 1998) and this current wave focuses on perceived difference between the sexes in co-educational classrooms (Protheroe, 2009; Gurian, Stevens & Daniels, 2009). With the intersection of middle schooling movement, focusing on learner centered classrooms (Pendergast & Bahr, 2010) and current educational agendas aimed at improving student performance and measurable learning outcomes (Ministerial Council on Education, Employment, Training and Youth Affairs, 2008), it is understandable that schools are exploring such student grouping options. However, after thirty years of international research into the efficacy of single sex classes in co-educational settings, the results still remain unclear. This paper seeks to navigate the ‘muddy waters’ of this body of research and suggests a framework to help guide school communities through the decision-making process associated with considering single sex classes.

Krüppel-associated box (KRAB)-associated co-repressor (KAP-1) Ser-473 phosphorylation regulates heterochromatin protein 1 (HP1- ) mobilization and DNA repair in heterochromatin

The DNA damage response encompasses a complex series of signaling pathways that function to regulate and facilitate the repair of damaged DNA. Recent studies have shown that the repair of transcriptionally inactive chromatin, named heterochromatin, is dependent upon the phosphorylation of the co-repressor, Krüppel-associated box (KRAB) domain-associated protein (KAP-1), by the ataxia telangiectasia-mutated (ATM) kinase. Co-repressors, such as KAP-1, function to regulate the rigid structure of heterochromatin by recruiting histone-modifying enzymes, such HDAC1/2, SETDB1, and nucleosome-remodeling complexes such as CHD3. Here, we have characterized a phosphorylation site in the HP1-binding domain of KAP-1, Ser-473, which is phosphorylated by the cell cycle checkpoint kinase Chk2. Expression of a nonphosphorylatable S473A mutant conferred cellular sensitivity to DNA-damaging agents and led to defective repair of DNA double-strand breaks in heterochromatin. In addition, cells expressing S473A also displayed defective mobilization of the HP1-β chromodomain protein. The DNA repair defect observed in cells expressing S473A was alleviated by depletion of HP1-β, suggesting that phosphorylation of KAP-1 on Ser-473 promotes the mobilization of HP1-β from heterochromatin and subsequent DNA repair. These results suggest a novel mechanism of KAP-1-mediated chromatin restructuring via Chk2-regulated HP1-β exchange from heterochromatin, promoting DNA repair.

Reconceptualising mega project success in Australian Defence : recognising the importance of value co-creation

Recent literature in project management has urged a re-conceptualisation of projects as a value co-creation process. Contrary to the traditional output-focused project methodology, the value creation perspective argues for the importance of creating new knowledge, processes, and systems for suppliers and customers. Stakeholder involvement is important in this new perspective, as the balancing of competing needs of stakeholders in mega projects becomes a major challenge in managing the value co-creation process. In this study we present interview data from three Australian defence mega projects to demonstrate that senior executives have a more complex understanding of project success than traditional iron triangle measures. In these mega defence projects, customers and other stakeholders actively engage in the value creation process, and over time both content and process value are created to increase defence and national capability. Value created and captured during and post projects are the key to true success.

Residence time investigation in a co-axial dielectric barrier discharge reactor

The residence time distribution (RTD) is a crucial parameter when treating engine exhaust emissions with a Dielectric Barrier Discharge (DBD) reactor. In this paper, the residence time of such a reactor is investigated using a finite element based software: COMSOL Multiphysics 4.3. Non-thermal plasma (NTP) discharge is being introduced as a promising method for pollutant emission reduction. DBD is one of the most advantageous of NTP technologies. In a two cylinder co-axial DBD reactor, tubes are placed between two electrodes and flow passes through the annuals between these barrier tubes. If the mean residence time increases in a DBD reactor, there will be a corresponding increase in reaction time and consequently, the pollutant removal efficiency can increase. However, pollutant formation can occur during increased mean residence time and so the proportion of fluid that may remain for periods significantly longer than the mean residence time is of great importance. In this study, first, the residence time distribution is calculated based on the standard reactor used by the authors for ultrafine particle (10-500 nm) removal. Then, different geometrics and various inlet velocities are considered. Finally, for selected cases, some roughness elements added inside the reactor and the residence time is calculated. These results will form the basis for a COMSOL plasma and CFD module investigation.

The Yonder project : literacy and social competency development in primary school students through co-creation of live performance

Since 2007 Kite Arts Education Program (KITE), based at Queensland Performing Arts Centre (QPAC), has been engaged in delivering a series of theatre-based experiences for children in low socio-economic primary schools in Queensland. The artist in residence (AIR) project titled Yonder includes performances developed by the children with the support and leadership of teacher artists from KITE for their community and parents/carers,supported by a peak community cultural institution. In 2009,Queensland Performing Arts Centre partnered with Queensland University of Technology (QUT) Creative Industries Faculty (Drama) to conduct a three-year evaluation of the Yonder project to understand the operational dynamics, artistic outputs and the educational benefits of the project. This paper outlines the research findings for children engaged in the Yonder project in the interrelated areas of literacy development and social competencies. Findings are drawn from six iterations of the project in suburban locations on the edge of Brisbane city and in regional Queensland.

A spectroscopic comparison of YBCO superconductors synthesised by solid-state and co-precipitation methods

Raman spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM) have been used to compare samples of YBa2Cu3O7 (YBCO) synthesised by the solid-state method and a novel co-precipitation technique. XRD results indicate that YBCO prepared by these two methods are phase pure, however the Raman and SEM results show marked differences between these samples.

Fine-grained Y2Cu2O5 powder from a co-precipitated precursor

A co-precipitation process is utilized to manufacture Y2Cu2O5 precursor powders. Upon calcination at high temperatures, such as 800 degrees C, the co-precipitated powder transforms to Y2Cu2O5. By selective variation of calcination parameters, grain-growth can be controlled to yield different sized Y2Cu2O5 powder, including sub-micron average sizes. ICP analysis, X-ray diffraction, electron microscopy, a.c. magnetic susceptibility and FT Raman are used to characterize phase development, morphology and purity of the powders.

Manufacture of specific BSCCO powder compositions by co-precipitation

A co-precipitation process for large-scale manufacture of bismuth-based HTSC powders has been demonstrated. Powders manufactured by this process have a high phase purity and precisely reproducible stoichiometry. Controlled time and temperature variations are used to convert precursors to HTSC compounds and to obtain specific particle-size distributions. The process has been demonstrated for a variety of compositions in the BSCCO system. Electron microscopy X-ray diffraction, inductively coupled plasma spectroscopy and magnetic-susceptibility measurements are used to characterize the powders.