1000 resultados para MAPPING NONUNIFORM CORROSION
Resumo:
This article examines the conditions of penal hope behind suggestions that the penal expansionism of the last three decades may be at a ‘turning point’. The article proceeds by outlining David Green’s (2013b) suggested catalysts of penal reform and considers how applicable they are in the Australian context. Green’s suggested catalysts are: the cycles and saturation thesis; shifts in the dominant conception of the offender; the global financial crisis (GFC) and budgetary constraints; the drop in crime; the emergence of the prisoner re‐entry movement; apparent shifts in public opinion; the influence of evangelical Christian ideas; and the Right on Crime initiative. The article then considers a number of other possible catalysts or forces: the role of trade unions; the role of courts; the emergence of recidivism as a political issue; the influence of ‘evidence based’/‘what works’ discourse; and the emergence of justice reinvestment (JR). The article concludes with some comments about the capacity of criminology and criminologists to contribute to penal reductionism, offering an optimistic assessment for the prospects of a reflexive criminology that engages in and engenders a wider politics around criminal justice issues.
Resumo:
Stress corrosion cracking (SCC) is a well known form of environmental attack in low carat gold jewellery. It is desirable to have a quick, easy and cost effective way to detect SCC in alloys and prevent them from being used and later failing in their application. A facile chemical method to investigate SCC of 9 carat gold alloys is demonstrated. It involves a simple application of tensile stress to a wire sample in a corrosive environment such as 1–10 % FeCl3 which induces failure in less than 5 minutes. In this study three quaternary (Au, Ag, Cu and Zn) 9 carat gold alloy compositions were investigated for their resistance to SCC and the relationship between time to failure and processing conditions is studied. It is envisaged that the use of such a rapid and facile screening procedure at the production stage may readily identify alloy treatments that produce jewellery that will be susceptible to SCC in its lifetime.
The electrochemical corrosion behaviour of quaternary gold alloys when exposed to 3.5% NaCl solution
Resumo:
Lower carat gold alloys, specifically 9 carat gold alloys, containing less than 40 % gold, and alloying additions of silver, copper and zinc, are commonly used in many jewellery applications, to offset high costs and poor mechanical properties associated with pure gold. While gold is considered to be chemically inert, the presence of active alloying additions raises concerns about certain forms of corrosion, particularly selective dissolution of these alloys. The purpose of this study was to systematically study the corrosion behaviour of a series of quaternary gold–silver–copper–zinc alloys using dc potentiodynamic scanning in saline (3.5 % NaCl) environment. Full anodic/cathodic scans were conducted to determine the overall corrosion characteristics of the alloy, followed by selective anodic scans and subsequent morphological and compositional analysis of the alloy surface and corroding media to determine the extent of selective dissolution. Varying degrees of selective dissolution and associated corrosion rates were observed after anodic polarisation in 3.5 % NaCl, depending on the alloy composition. The corrosion behaviour of the alloys was determined by the extent of anodic reactions which induce (1) formation of oxide scales on the alloy surface and or (2) dissolution of Zn and Cu species. In general, the improved corrosion characteristics of alloy #3 was attributed to the composition of Zn/Cu in the alloy and thus favourable microstructure promoting the formation of protective oxide/chloride scales and reducing the extent of Cu and Zn dissolution.
Resumo:
In contemporary game development circles the ‘game making jam’ has become an important rite of passage and baptism event, an exploration space and a central indie lifestyle affirmation and community event. Game jams have recently become a focus for design researchers interested in the creative process. In this paper we tell the story of an established local game jam and our various documentation and data collection methods. We present the beginnings of the current project, which seeks to map the creative teams and their process in the space of the challenge, and which aims to enable participants to be more than the objects of the data collection. A perceived issue is that typical documentation approaches are ‘about’ the event as opposed to ‘made by’ the participants and are thus both at odds with the spirit of the jam as a phenomenon and do not really access the rich playful potential of participant experience. In the data collection and visualisation projects described here, we focus on using collected data to re-include the participants in telling stories about their experiences of the event as a place-based experience. Our goal is to find a means to encourage production of ‘anecdata’ - data based on individual story telling that is subjective, malleable, and resists collection via formal mechanisms - and to enable mimesis, or active narrating, on the part of the participants. We present a concept design for data as game based on the logic of early medieval maps and we reflect on how we could enable participation in the data collection itself.
Resumo:
Whilst there is an excellent and growing body of literature around female criminality underpinned by feminist methodologies, the nitty gritty of the methodological journey is nowhere as well detailed as it is in the context of the Higher Degree Research (HDR) thesis. Thus the purpose of this paper is threefold: i) to explore a range of feminist methodologies underpinning 20 Australian HDR theses focussing on female criminality; ii) to identify and map the governance/ethics tensions experienced by these researchers whilst undertaking high risk research in the area of female offending; and iii) to document strategies drawn from negotiations, resolutions and outcomes to a range of gate-keeping issues. By exploring the strategies used by these researchers, this paper aims to: promote discussion on feminist methodologies; highlight pathways that may be created when negotiating the challenging process of accessing data pertinent to this relatively understudied area; contribute to a community of practice; and provide useful insights into what Mason & Stubbs (2010:16) refer to as “the open and honest reflexivity through the research process by describing the assumptions, and hiccups” for future researchers navigating governance landscapes.
Resumo:
This paper offers a discussion on the “mundane” or quotidian aspects of that software which might at first glance seem to be a fine example of the extraordinary. It looks at game worlds in terms of an ancient human desire to articulate place in the world and pursues a design concept which resonates with this practice in order to enable a more mundane exploitation of such spatial representations: the claiming of place.
Resumo:
Forward genetic screens have identified numerous genes involved in development and metabolism, and remain a cornerstone of biological research. However, to locate a causal mutation, the practice of crossing to a polymorphic background to generate a mapping population can be problematic if the mutant phenotype is difficult to recognize in the hybrid F2 progeny, or dependent on parental specific traits. Here in a screen for leaf hyponasty mutants, we have performed a single backcross of an Ethane Methyl Sulphonate (EMS) generated hyponastic mutant to its parent. Whole genome deep sequencing of a bulked homozygous F2 population and analysis via the Next Generation EMS mutation mapping pipeline (NGM) unambiguously determined the causal mutation to be a single nucleotide polymorphisim (SNP) residing in HASTY, a previously characterized gene involved in microRNA biogenesis. We have evaluated the feasibility of this backcross approach using three additional SNP mapping pipelines; SHOREmap, the GATK pipeline, and the samtools pipeline. Although there was variance in the identification of EMS SNPs, all returned the same outcome in clearly identifying the causal mutation in HASTY. The simplicity of performing a single parental backcross and genome sequencing a small pool of segregating mutants has great promise for identifying mutations that may be difficult to map using conventional approaches.
Resumo:
This thesis presents a novel approach to mobile robot navigation using visual information towards the goal of long-term autonomy. A novel concept of a continuous appearance-based trajectory is proposed in order to solve the limitations of previous robot navigation systems, and two new algorithms for mobile robots, CAT-SLAM and CAT-Graph, are presented and evaluated. These algorithms yield performance exceeding state-of-the-art methods on public benchmark datasets and large-scale real-world environments, and will help enable widespread use of mobile robots in everyday applications.
Resumo:
Significant problems confront our child protection out-of-home care system including: high costs; increasing numbers of children and young people entering and remaining in care longer; high frequency of placement movement; and, negative whole-of-life outcomes for children and young people who have exited care. National policy and research agendas recognise the importance of enhancing the evidence base in out-of-home care to inform the development of policy, programs and practice, and improve longitudinal outcomes of children and young people. The authors discuss the concept of placement trajectory as a framework for research and systems analysis in the out-of-home context. While not without limitations, the concept of placement trajectory is particularly useful in understanding the factors influencing placement movement and stability. Increasing the evidence base in this area can serve to enhance improved outcomes across the lifespan for children and young people in the out-of-home care system.
Resumo:
The ability to measure surface temperature and represent it on a metrically accurate 3D model has proven applications in many areas such as medical imaging, building energy auditing, and search and rescue. A system is proposed that enables this task to be performed with a handheld sensor, and for the first time with results able to be visualized and analyzed in real-time. A device comprising a thermal-infrared camera and range sensor is calibrated geometrically and used for data capture. The device is localized using a combination of ICP and video-based pose estimation from the thermal-infrared video footage which is shown to reduce the occurrence of failure modes. Furthermore, the problem of misregistration which can introduce severe distortions in assigned surface temperatures is avoided through the use of a risk-averse neighborhood weighting mechanism. Results demonstrate that the system is more stable and accurate than previous approaches, and can be used to accurately model complex objects and environments for practical tasks.
Resumo:
Enormous progress has been made towards understanding the role of specific factors in the process of epithelial-mesenchymal transition (EMT); however, the complex underlying pathways and the transient nature of the transition continues to present significant challenges. Targeting tumour cell plasticity underpinning EMT is an attractive strategy to combat metastasis. Global gene expression profiling and high-content analyses are among the strategies employed to identify novel EMT regulators. In this review, we highlight several approaches to systematically interrogate key pathways involved in EMT, with particular emphasis on the features of multiparametric, high-content imaging screening strategies that lend themselves to the systematic discovery of highly significant modulators of tumour cell plasticity.
Resumo:
Reliable robotic perception and planning are critical to performing autonomous actions in uncertain, unstructured environments. In field robotic systems, automation is achieved by interpreting exteroceptive sensor information to infer something about the world. This is then mapped to provide a consistent spatial context, so that actions can be planned around the predicted future interaction of the robot and the world. The whole system is as reliable as the weakest link in this chain. In this paper, the term mapping is used broadly to describe the transformation of range-based exteroceptive sensor data (such as LIDAR or stereo vision) to a fixed navigation frame, so that it can be used to form an internal representation of the environment. The coordinate transformation from the sensor frame to the navigation frame is analyzed to produce a spatial error model that captures the dominant geometric and temporal sources of mapping error. This allows the mapping accuracy to be calculated at run time. A generic extrinsic calibration method for exteroceptive range-based sensors is then presented to determine the sensor location and orientation. This allows systematic errors in individual sensors to be minimized, and when multiple sensors are used, it minimizes the systematic contradiction between them to enable reliable multisensor data fusion. The mathematical derivations at the core of this model are not particularly novel or complicated, but the rigorous analysis and application to field robotics seems to be largely absent from the literature to date. The techniques in this paper are simple to implement, and they offer a significant improvement to the accuracy, precision, and integrity of mapped information. Consequently, they should be employed whenever maps are formed from range-based exteroceptive sensor data. © 2009 Wiley Periodicals, Inc.
Resumo:
This paper uses innovative content analysis techniques to map how the death of Oscar Pistorius' girlfriend, Reeva Steenkamp, was framed on Twitter conversations. Around 1.5 million posts from a two-week timeframe are analyzed with a combination of syntactic and semantic methods. This analysis is grounded in the frame analysis perspective and is different than sentiment analysis. Instead of looking for explicit evaluations, such as “he is guilty” or “he is innocent”, we showcase through the results how opinions can be identified by complex articulations of more implicit symbolic devices such as examples and metaphors repeatedly mentioned. Different frames are adopted by users as more information about the case is revealed: from a more episodic one, highly used in the very beginning, to more systemic approaches, highlighting the association of the event with urban violence, gun control issues, and violence against women. A detailed timeline of the discussions is provided.
Resumo:
This article reports key findings from a comparative survey of the role perceptions, epistemological orientations and ethical views of 1800 journalists from 18 countries. The results show that detachment, non-involvement, providing political information and monitoring the government are considered essential journalistic functions around the globe. Impartiality, the reliability and factualness of information, as well as adherence to universal ethical principles are also valued worldwide, though their perceived importance varies across countries. Various aspects of interventionism, objectivism and the importance of separating facts from opinion, on the other hand, seem to play out differently around the globe. Western journalists are generally less supportive of any active promotion of particular values, ideas and social change, and they adhere more to universal principles in their ethical decisions. Journalists from non-western contexts, on the other hand, tend to be more interventionist in their role perceptions and more flexible in their ethical views.
Resumo:
While the study of foreign news flows has received considerable attention from communication scholars for quite some time, it has typically focused on political or ‘hard’ news, at the expense of other types of journalistic content. This article argues that, as the foreign news hole is shrinking, travel journalism is becoming an increasingly important source of information about foreign countries in the news media. It reports the results of a comparative study of newspaper travel sections in Australia, Canada, New Zealand, and the UK, and argues that travel journalism often replicates the imbalances found in foreign news flows. Well-known factors – such as regionalism, powerful nations, cultural proximity, the role played by big neighbours and the diversity of coverage – are also powerful determinants in travel journalism. At the same time, a country’s tourist behaviour also plays a role but is often overshadowed by other factors.