A professional learning program based on a representation intensive pedagogical approach

A representation-intensive pedagogical approach challenges students to generate and negotiate the representations (text, graphs, models, diagrams) that constitute the discursive practices of science, rather than focusing on the text-based, definitional versions of concepts. Previous research conducted on a small scale with a few topics and teachers successfully demonstrated enhanced outcomes for students, in terms of sustained engagement with ideas, and quality learning, and for teachers’ enhanced pedagogical knowledge, and epistemological understanding. This paper explores the efficacy of embedding a representations-intensive pedagogical approach into a state-wide professional learning program that was delivered to Victorian secondary science teachers in 2010/2011. The professional learning program involved participating teachers undertaking two successive days of professional development, then completing a small classroom-based project in their schools before returning for the third day of professional development. The program was supported by online drupal website. In determining the impact of the professional learning program on the teachers’ practice data was collected in the form of program participant surveys, presentations of the teachers’ classroom-based projects, focus group interviews and phone interviews. Teachers demonstrated the applicability of this pedagogical approach by adapting it to a variety of science topics.

Empowering teachers through a professional learning program that focused on a representation intensive pedagogical approach

A representation-intensive pedagogical approach challenges students to generate and negotiate the representations (text, graphs, models, diagrams) that constitute the discursive practices of science, rather than focusing on the text-based, definitional versions of concepts. It thus represents a more active view of knowledge than traditional structural approaches. Previous research conducted on a small scale with a few topics and teachers, successfully demonstrated enhanced outcomes for students, in terms of sustained engagement with ideas, and quality learning, and for teachers enhanced pedagogical knowledge, and epistemological understanding. This paper explores the efficacy of embedding a representations-intensive pedagogical approach into a state-wide professional learning program that was delivered to secondary science teachers in Victoria, Australian, in 2010/2011. The professional learning program involved participating teachers undertaking two successive days of professional development, then completing a small classroom-based project in their schools before returning for the third day of professional development. The program was supported by on online drupal website. In determining the impact of the professional learning program on the teachers’ practice data was collected in the form of program participant surveys, presentations of the teachers’ classroom-based projects, focus group interviews and phone interviews.

Underdetermined blind source separation by parallel factor analysis in time-frequency domain

This paper presents a new time-frequency approach to the underdetermined blind source separation using the parallel factor decomposition of third-order tensors. Without any constraint on the number of active sources at an auto-term time-frequency point, this approach can directly separate the sources as long as the uniqueness condition of parallel factor decomposition is satisfied. Compared with the existing two-stage methods where the mixing matrix should be estimated at first and then used to recover the sources, our approach yields better source separation performance in the presence of noise. Moreover, the mixing matrix can be estimated at the same time of the source separation process. Numerical simulations are presented to show the superior performance of the proposed approach to some of the existing two-stage blind source separation methods that use the time-frequency representation as well.

Racialized urban America and Holocaust film : negotiating the limits of representation

Sidney Lumet’s influential film The Pawnbroker (1964) is one of the earliest films to consider the encounter between Holocaust narratives and low-income, urban American racial minorities. As much concerned with contemporary ‘race relations’ in the United States as it is with the Nazis’ persecution of Europe’s Jews, the film intertwines the story of Holocaust survivor Sol Nazerman with the social tensions of 1960s America, represented in his relationship with the young Puerto Rican shop assistant Jesus Oritz. The film stylistically juxtaposes raw footage of concentration camp existence with dismal images of New York slum life. Against these backdrops, the protagonist’s climactic ‘silent scream’ emblematically merges the repressed trauma of the survivor with the filmmaker’s interest in race relations, a theme that has undergone various transformations in a number of films since. One film that contemporizes this encounter is Richard LaGravenese’s Freedom Writers (2007). As opposed to the tragic outcome of the pawnbroker’s induction into urban America, here the Holocaust is a redemptive tool that permits inner-city Black and Latino youth to contextualize their own suffering. After reading The Diary of Anne Frank, this group of ‘at-risk’ sophomores to inspired to collaborate on an ultimately successful effort to bring Miep Geis, the woman who sheltered Anne Frank, to speak at their high school. Foregrounded by the 1992 Los Angeles riots, gentiles teacher Erin Gruwell and savior Miep Geis transform the Holocaust from an amplified parallel of American slums into an event that permits the children of American postcoloniality to triumph in spite of their socio-economic circumstances. Underlining the tension between the Jewish specificity and unprecedented nature of the Holocaust, and the need to generate Holocaust narratives that intersect with intrinsically racialized American narratives, such films have significant implications for how collective memories of suffering are constructed and contested.

Sparse subspace representation for spectral document clustering

We present a novel method for document clustering using sparse representation of documents in conjunction with spectral clustering. An ℓ1-norm optimization formulation is posed to learn the sparse representation of each document, allowing us to characterize the affinity between documents by considering the overall information instead of traditional pair wise similarities. This document affinity is encoded through a graph on which spectral clustering is performed. The decomposition into multiple subspaces allows documents to be part of a sub-group that shares a smaller set of similar vocabulary, thus allowing for cleaner clusters. Extensive experimental evaluations on two real-world datasets from Reuters-21578 and 20Newsgroup corpora show that our proposed method consistently outperforms state-of-the-art algorithms. Significantly, the performance improvement over other methods is prominent for this datasets.

The descent of Morgan in Australia: kinship representation from the Australian colonies

Morgan had two extraordinary disciples in Lorimer Fison and Alfred Howitt in Australia. They were inspired by Morgan’s kinship schedule and were profoundly engaged in the method and theory of the collection of kinship data and its interpretation. Fison began using the schedule in Fiji in 1869. Soon after his first contact with Howitt, in 1873, they changed the method of collection of kinship terminologies. This paper traces the shift from tabulated kinship lists to family trees and the use of sticks to represent relationships (nearly twenty years before Rivers’ celebrated ‘genealogical method’), as well as efforts to find new means of representing kinship through experimentation with ‘ graphic formulae’ inspired by chemical equations. These innovations first occurred through the gathering of kinship data about the Kŭnai of Gippsland, Victoria, and crucially involved close collaboration between Howitt and his Kŭnai consultant Tulaba. What was revealed in this process was an indigenous kinship system quite different from that found in other parts of colonial Australia known at the time. Fison and Howitt explained this system as transitional between two stages in terms of Morgan’s evolutionary scheme, but at the same time challenged the assumption that the general scheme could be applied to Australia. While the details of Morgan’s evolutionary stages have faded from view, the methods of collection, representation, transmission, comparison and interpretation of kinship data are still live issues in anthropology today. The kind of kinship system discovered in Gippsland involved neutralisation of the cross-parallel distinctions, distinctions that are otherwise typical of Australia. Such neutralisation can now be shown to occur elsewhere in Australia. There does indeed seem to have been a transition from a Dravidianate system with cross-parallel distinctions to ‘overlays’ of cross-parallel neutralisation, and finally a complete loss in some generations of such distinctions in the terminology. These discoveries open up possibilities of rebuilding a diachronic theory of kinship change and evolution, incorporating some of the insights of Fison and Howitt, though without their specific hypotheses, either of local developments in Gippsland or the grand scheme of Morgan.

Human identification from ECG signals via sparse representation of local segments

This work proposes a novel framework to extract compact and discriminative features from Electrocardiogram (ECG) signals for human identification based on sparse representation of local segments. Specifically, local segments extracted from an ECG signal are projected to a small number of basic elements in a dictionary, which is learned from training data. A final representation is extracted by performing a max pooling procedure over all the sparse coefficient vectors in the ECG signal. Unlike most of existing methods for human identification from ECG signals which require segmentation of individual heartbeats or extraction of fiducial points, the proposed method does not need to segment individual heartbeats or detect any fiducial points. The method achieves an 99.48% accuracy on a 100 subjects dataset constructed from a publicly available database, which demonstrates that both local and global structural information are well captured to characterize the ECG signals.

Tribes and political representation: the case of post-war Iraq

 Ten years have passed since the US-led invasion of Iraq in 2003, and the political scene in Iraq is still blurry. Iraq was promoted to be the democratic example in the Middle East. The US came to Iraq to “create” a democratic system that can be a model for other countries in the region. A major factor in creating such environment is by changing the radical centralised totalitarian regime with a weak state that can give more space to building the civil society in new Iraq (Looney, 2003). Nonetheless, the socio-economic and political indicators of the newly installed political “democratic” system point to notable failures. Apart from poor socio-economic factors, the new political elite has either misused democracy for personal, ethno-sectarian or partisan gains or abused the system to ensure their long lasting presence in the decision making arena. Corruption, disconnection from electorate, poor performance and carelessness of politicians and failing state service provisions have all made citizens question the feasibility of political participation in elections. The electorate seem to have lesser faith in the political parties and blocs whose legitimacy of representation  is at stake. Noticeably, tribes have stepped forward to mobilise people as a non-partisan and independent powerful social structure. They have been active in lobbying the state as well as encouraging their members for active participation. This paper discusses the extent to which Iraqi tribes are involved in political participation. It explores their roles in active citizenship and the way they represent and mobilise their  members. It also probes whether tribes have the influence on shaping the political trajectory in Iraq.

Sparse Representations of Image via Overcomplete Dictionary Learned by Adaptive Non-orthogonal Sparsifying Transform

How to learn an over complete dictionary for sparse representations of image is an important topic in machine learning, sparse coding, blind source separation, etc. The so-called K-singular value decomposition (K-SVD) method [3] is powerful for this purpose, however, it is too time-consuming to apply. Recently, an adaptive orthogonal sparsifying transform (AOST) method has been developed to learn the dictionary that is faster. However, the corresponding coefficient matrix may not be as sparse as that of K-SVD. For solving this problem, in this paper, a non-orthogonal iterative match method is proposed to learn the dictionary. By using the approach of sequentially extracting columns of the stacked image blocks, the non-orthogonal atoms of the dictionary are learned adaptively, and the resultant coefficient matrix is sparser. Experiment results show that the proposed method can yield effective dictionaries and the resulting image representation is sparser than AOST.

Semi-supervised classification based on subspace sparse representation

Graph plays an important role in graph-based semi-supervised classification. However, due to noisy and redundant features in high-dimensional data, it is not a trivial job to construct a well-structured graph on high-dimensional samples. In this paper, we take advantage of sparse representation in random subspaces for graph construction and propose a method called Semi-Supervised Classification based on Subspace Sparse Representation, SSC-SSR in short. SSC-SSR first generates several random subspaces from the original space and then seeks sparse representation coefficients in these subspaces. Next, it trains semi-supervised linear classifiers on graphs that are constructed by these coefficients. Finally, it combines these classifiers into an ensemble classifier by minimizing a linear regression problem. Unlike traditional graph-based semi-supervised classification methods, the graphs of SSC-SSR are data-driven instead of man-made in advance. Empirical study on face images classification tasks demonstrates that SSC-SSR not only has superior recognition performance with respect to competitive methods, but also has wide ranges of effective input parameters.

Finding the edge : online persona creation by fringe artists

Self-presentation through the creation of profiles and pages on digitally networked spaces is becoming ever more ubiquitous. In order to develop greater depth of understanding of the place of social media in our self-identification practice, my dissertation investigates the experiences of online persona creation by eight artists. Drawing on sociological and cultural studies approaches to understanding identity as performance, I tie current artists’ presentational and representational practices to historically grounded, socio-culturally constructed discourses of ‘artistness’. Through this connection, I argue that the creation of online persona has not radically changed notions of what it means to be an artist, or how artistness is represented and understood by audiences of fans or followers, but rather that digital technology has allowed for renegotiation of the boundaries of artistness that still draws from historical understandings of the role and persona of the artist. This shifting of boundaries, allowing for more inclusivity within the art world, is demonstrated by my focus on ‘fringe’ artists: those whose creative practice places them outside of the traditional art world and its existing structures of representation, distribution and consumption. The eight fringe artists who participated in this study are drawn from street art, performance poetry, craftivism and tattoo.

Interpretative Phenomenological Analysis drives the methodological focus on the experiences of the artists. Rather than a consideration of behaviour and habit, or what the artists do, this phenomenological approach allowed me to instead focus on what it is like for the artists to create persona, what drives particular types of representational practices. Using unstructured interviews, and online listening as an extension of participant observation, the artists’ narratives of experience are expressed through transcript extracts and screenshots: both are necessary to fully explore the nature of online persona creation.

My analysis of the artists experiences has demonstrated that there are three somewhat distinct registers of performance with which an artist’s persona can engage: the professional register, where one demonstrates ones proficiency, experience, popularity, and professionalism; the personal register, where one connects with
wider social and political interests and activities; and the intimate register, where one allows the audience in to one’s private world. These three registers occupy the same performance space, but are implicitly or explicitly for different segments of the digitally networked audience of fans, followers, friends and family. The complexity of the performance and reception of these registers is influenced by the shared nature of the performance space – where previously different roles would be performed for different audiences without reference to one another, the networked nature of online social media influences decisions of how much, and when, to share with whom.

Interpreted here using themes of strategy|happenstance, specialisation|diversification, visibility|self-protection,
self|others and work|play, the professional, personal and intimate registers of performance enable us to see the consideration and care with which each participant creates their artists persona. The experiences of performing the self in these three registers, as presented here, provides an insight into the complexities involved in creating online persona, while also demonstrating that this type of presentation of self is, in itself, no different from the types of role play and performance of self that has arguably always occurred in our physical world. Despite focusing on the role and performance of artistness, this dissertation speaks to the creation and performance of online persona more broadly. 

Representation of multiculturalism in urban green spaces : a review of immigrants' experiences in Australia

Rapid population influx due to migration in Australia has produced diverse cultural landscapes, which become visible in cities as physical forms, settings and symbols produced by different ethnic communities. Scholars have argued that people moving away from the country of their birth, whether this be a necessary migration, labour mobility or voluntary migration, results in a difficult process of resettlement for families and individuals. To provide a cohesive multicultural society for all citizens, it is essential to understand how immigrants perceive their new environments and how they make connections in a new land in the process of cultural renewal. While the policy of ‘multiculturalism’ has had a rocky road since the optimistic 1970s, a drive through many suburbs in Australian cities shows buildings, festivals and communal gatherings of people that express and refer to diverse cultural backgrounds. Urban green spaces, ranging from private home gardens to public parks and botanical gardens, play an important role in the life of immigrants. Besides psychological and the restorative effects of urban green spaces, these spaces are public places that provide opportunities for recreation, social gatherings, and the celebration of collective cultural values and events such as festivals for many communities. This study aims to raise awareness of ethnicity as an important issue in park settings and spaces. It investigates the interrelationship between these cultural practices in the urban park environment, in relation to ethnic and cultural identity and physical settings. The concept of transculturalism – reinventing a new common culture as a result of migration to a new place – can help the analysis of the affects and the perception of urban green spaces. The paper will review different experiences of immigrants in relation to the use and perception of urban green spaces, developing alternative perspectives about the Australian landscapes.

Generalised damage identification scheme via sparse representation

Structures inevitably deteriorate during their service lives. Therefore, the methods capable of identifying and assessing various damages in a structure timely and accurately have drawn increasing attention. From a broader perspective, structural damage identification problem can be regarded as a pattern recognition problem by using sparse representation techniques. The unknown signal/feature from a damaged structure can be associated to a known type of signal/feature in a “dictionary”, leading to damage identification. From this new angle, an innovative damage identification scheme has been proposed by the authors. In this paper, two important techniques of this scheme are further discussed, namely the construction of dictionary and the choice of parameters. The numerical simulated soil-pipe system is used for verifying the performance of the proposed method. The results demonstrate that this damage identification scheme will be a promising tool for structural health monitoring.

Voice, post-structural representation and the subjectivity of ‘included’ students

Aligned with the broader movement from structuralism to the post-structuralisms [Lather, P. 2013. “Methodology-21: What Do We Do in the Afterward?” International Journal of Qualitative Studies in Education 26 (6): 634–645; St. Pierre, E. A. 2009. “Afterword: Decentering Voice in Qualitative Inquiry.” In Voice in Qualitative Inquiry: Challenging Conventional, Interpretive, and Critical Conceptions in Qualitative Research, edited by A. Y. Jackson and L. A. Mazzei, 221–236. London: Routledge; St. Pierre, E. A. 2013. “The Posts Continue: Becoming.” International Journal of Qualitative Studies in Education 26 (6): 646–657], research in disability studies for the past two decades has found ‘the potholes’ [Miller, L., J. B. Whalley, and I. Stronach. 2012. “From Structuralism to Poststructuralism.” In Research Methods in the Social Sciences, edited by B. Somekh and C. Lewin. London: SAGE] of disability rights scholarship. In this paper, I offer a critical research framework in the field of disability studies in education that is theoretical, political and personal. Concentrating on the positioning of disability, I draw on the methodological tools of post-structural representation, subjectivity and constructivist grounded theory to study how discursive practices within (and around) secondary schools shape ‘included’ disabled subjects. In the paper I develop this framework and then demonstrate its application in ongoing research that critically counters the conventions that marginalize particular students in schools.