409 resultados para Dunkl-Bessel Transform
Resumo:
Traditional area-based matching techniques make use of similarity metrics such as the Sum of Absolute Differences(SAD), Sum of Squared Differences (SSD) and Normalised Cross Correlation (NCC). Non-parametric matching algorithms such as the rank and census rely on the relative ordering of pixel values rather than the pixels themselves as a similarity measure. Both traditional area-based and non-parametric stereo matching techniques have an algorithmic structure which is amenable to fast hardware realisation. This investigation undertakes a performance assessment of these two families of algorithms for robustness to radiometric distortion and random noise. A generic implementation framework is presented for the stereo matching problem and the relative hardware requirements for the various metrics investigated.
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The mining environment, being complex, irregular and time varying, presents a challenging prospect for stereo vision. For this application, speed, reliability, and the ability to produce a dense depth map are of foremost importance. This paper assesses the suitability of a number of matching techniques for use in a stereo vision sensor for close range scenes consisting primarily of rocks. These include traditional area-based matching metrics, and non-parametric transforms, in particular, the rank and census transforms. Experimental results show that the rank and census transforms exhibit a number of clear advantages over area-based matching metrics, including their low computational complexity, and robustness to certain types of distortion.
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The mining environment, being complex, irregular and time varying, presents a challenging prospect for stereo vision. For this application, speed, reliability, and the ability to produce a dense depth map are of foremost importance. This paper evaluates a number of matching techniques for possible use in a stereo vision sensor for mining automation applications. Area-based techniques have been investigated because they have the potential to yield dense maps, are amenable to fast hardware implementation, and are suited to textured scenes. In addition, two non-parametric transforms, namely, the rank and census, have been investigated. Matching algorithms using these transforms were found to have a number of clear advantages, including reliability in the presence of radiometric distortion, low computational complexity, and amenability to hardware implementation.
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The authors present a qualitative and quantitative comparison of various similarity measures that form the kernel of common area-based stereo-matching systems. The authors compare classical difference and correlation measures as well as nonparametric measures based on the rank and census transforms for a number of outdoor images. For robotic applications, important considerations include robustness to image defects such as intensity variation and noise, the number of false matches, and computational complexity. In the absence of ground truth data, the authors compare the matching techniques based on the percentage of matches that pass the left-right consistency test. The authors also evaluate the discriminatory power of several match validity measures that are reported in the literature for eliminating false matches and for estimating match confidence. For guidance applications, it is essential to have and estimate of confidence in the three-dimensional points generated by stereo vision. Finally, a new validity measure, the rank constraint, is introduced that is capable of resolving ambiguous matches for rank transform-based matching.
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A frame-rate stereo vision system, based on non-parametric matching metrics, is described. Traditional metrics, such as normalized cross-correlation, are expensive in terms of logic. Non-parametric measures require only simple, parallelizable, functions such as comparators, counters and exclusive-or, and are thus very well suited to implementation in reprogrammable logic.
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Although the drivers of innovation have been studied extensively in construction, greater attention is required on how innovation diffusion can be effectively assessed within this complex and interdependent project-based industry. The authors draw on a highly cited innovation diffusion model by Rogers (2006) and develop a tailored conceptual framework to guide future empirical work aimed at assessing innovation diffusion in construction. The conceptual framework developed and discussed in this paper supports a five-stage process model of innovation diffusion namely: 1) knowledge and idea generation, 2) persuasion and evaluation; 3) decision to adopt, 4) integration and implementation, and 5) confirmation. As its theoretical contribution, this paper proposes three critical measurements constructs which can be used to assess the effectiveness of the diffusion process. These measurement constructs comprise: 1) nature and introduction of an innovative idea, 2) organizational capacity to acquire, assimilate, transform and exploit an innovation, and 3) rates of innovation facilitation and adoption. The constructs are interpreted in the project-based context of the construction industry, extending the contribution of general management theorists. Research planned by the authors will test the validity and reliability of the constructs developed in this paper.
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An important component of current models for interstellar and circumstellar evolution is the infrared (IR)spectral data collected from stellar outflows around oxygen-rich stars and from the general interstellar medium [1]. IR spectra from these celestial bodies are usually interpreted as showing the general properties of sub-micron sized silicate grains [2]. Two major features at 10 and 20 microns are reasonably attributed to amorphous olivine or pyroxene (e.g. Mg2Si04 or MgSi03) on the basis of comparisons with natural standards and vapor condensed silicates [3-6]. In an attempt to define crystallisation rates for spectrally amorphous condensates, Nuth and Donn [5] annealed experimentally produced amorphous magnesium silicate smokes at 1000K. On analysing these smokes at various annealing times, Nuth and Donn [5] showed that changes in crystallinity measured by bulk X-ray diffraction occured at longer annealing times (days) than changes measured by IR spectra (a few hours). To better define the onset of crystallinity in these magnesium silicates, we have examined each annealed product using a JEOL 1OOCX analytical electron microscope (AEM). In addition, the development of chemical diversity with annealing has been monitored using energy dispersive spectroscopy of individual grains from areas <20nm in diameter. Furthermore, the crystallisation kinetics of these smokes under ambient, room temperature conditions have been examined using bulk and fourier transform infrared (FTIR)spectra.
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A well-characterized kaolinite has been hydrated in order to test the hypothesis that platey kaolinite will roll upon hydration. Kaolinite hydrates are prepared by repeated intercalation of kaolinite with potassium acetate and subsequent washing with water. On hydration, kaolinite plates roll along the major crystallographic directions to form tubes identical to proper tubular halloysite. Most tubes are elongated along the b crystallographic axis, while some are elongated along the a axis. Overall, the tubes exhibit a range of crystallinity. Well-ordered examples show a 2-layer structure, while poorly ordered tubes show little or no 3-dimensional order. Cross-sectional views of the formed tubes show both smoothly curved layers and planar faces. These characteristics of the experimentally formed tubes are shared by natural halloysites. Therefore, it is proposed that planar kaolinite can transform to tubular halloysite.
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National flag carriers are struggling for survival, not only due to classical reasons such as increase in fuel and tax or natural disasters, but largely due to the inability to quickly adapt to its competitive environment – the emergence of budget and Persian Gulf airlines. In this research, we investigate how airlines can transform their business models via technological and strategic capabilities to become profitable and sustainable passenger experience companies. To formulate recommendations, we analyze customer sentiments via social media to understand what people are saying about the airlines.
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The knowledge economy relies on the diffusion and use of knowledge as well as its creation (Houghton and Sheenan, 2000). The future success of economic activity will depend on the capacity of organisations to transform by increasing their flexibility. In particular, this transformation is dependant on a decentralised, networked and multi-skilled workforce. To help organisations transition, new strategies and structures for education are required. Education systems need to concentrate less on specialist skills and more on the development of people with broad-based problem solving skills that are adaptable, with social and inter-personal communication skills necessary for networking and communication. This paper presents the findings of a ‘Knowledge Economy Market Development Mapping Study’ conducted to identify the value of design education programs from primary through to tertiary level in Queensland, Australia. The relationship of these programs to the development of the capacities mentioned above is explored. The study includes the collection of qualitative and quantitative data consisting of a literature review, focus groups and survey. Recommendations for the future development of design education programs in Queensland, Australia are proposed, and future research opportunities are presented and discussed.
The creative citizen : understanding the value of design education programs in the knowledge economy
Resumo:
The knowledge economy relies on the diffusion and use of knowledge as well as its creation (Houghton and Sheenan, 2000). The future success of economic activity will depend on the capacity of organisations to transform by increasing their flexibility. In particular, this transformation is dependant on a decentralised, networked and multi-skilled workforce. To help organisations transition, new strategies and structures for education are required. Education systems need to concentrate less on specialist skills and more on the development of people with broad-based problem solving skills that are adaptable, with social and inter-personal communication skills necessary for networking and communication. This paper presents the findings of a ‘Knowledge Economy Market Development Mapping Study’ conducted to identify the value of design education programs from primary through to tertiary level in Queensland, Australia. The relationship of these programs to the development of the capacities mentioned above is explored. The study includes the collection of qualitative and quantitative data consisting of a literature review, focus groups and survey. Recommendations for the future development of design education programs in Queensland, Australia are proposed, and future research opportunities are presented and discussed.
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The ‘Fashion Tales’ Conference identifies three fashion discourses: that of making, that of media, and that of scholarship. We propose a fourth, which provides a foundational base for the others: the discourse of fashion pedagogy. We begin with the argument that to thrive in any of these discourses, all fashion graduates require the ability to navigate the complexities of the 21st century fashion industry. Fashion graduates emerge into a professional world which demands a range of high level capabilities above and beyond those traditionally acknowledged by the discipline. Professional education in fashion must transform itself to accommodate these imperatives. In this paper, we document a tale of fashion learning, teaching and scholarship – the tale of a highly successful future-orientated boutique university-based undergraduate fashion course in Queensland, Australia. The Discipline consistently maintains the highest student satisfaction and lowest attrition of any course in the university, achieves extremely competitive student satisfaction scores when compared with other courses nationally and internationally, and reports outstanding graduate employment outcomes. The core of the article addresses how the course effectively balances five key pedagogical tensions identified from the findings of in-depth focus groups with graduating students, and interviews with teaching staff. The pedagogical tensions are: high concept/ authenticity; high disciplinarity/ interdisciplinarity; high rigour/ play; high autonomy/ scaffolding; and high individuality/ community, where community can be further divided into high challenge and high support. We discuss each of these tensions and how they are characterised within the course, using rich descriptions given by the students. We also draw upon the wider andragogical and learning futures literatures to link the tensions with what is already known about excellence in 21st century higher and further education curriculum and pedagogic practice. We ask: as the fashion industry becomes truly globalised, virtualised, and diversified, and as initial professional training for the industry becomes increasingly massified and performatised, what are the best teaching approaches to produce autonomous, professionally capable, enterprising and responsible graduates into the future? Can the pedagogical balances described in this case study be maintained in the light of these powerful external forces, and if so, how?
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This case-study exemplifies a ‘writing movement’, which is currently occurring in various parts of Australia through the support of social media. A concept emerging from the café scene in San Francisco, ‘Shut Up and Write!’ is a meetup group that brings writers together at a specific time and place to write side by side, thus making writing practice, social. This concept has been applied to the academic environment and our case-study explores the positive outcomes in two locations: RMIT University and QUT. We believe that this informal learning practice can be implemented to assist research students in developing academic skills. DESCRIPTION: Please describe your practice as a case study, including its context; challenge addressed; its aims; what it is; and how it supports creative practice PhD students or supervisors. Additional information may include: the outcomes; key factors or principles that contribute to its effectiveness; anticipated impact/evidence of impact. Research students spend the majority of their time outside of formal learning environments. Doctoral candidates enter their degree with a range of experience, knowledge and needs, making it difficult to provide writing assistance in a structured manner. Using a less structured approach to provide writing assistance has been trialled with promising results (Boud, Cohen, & Sampson, 2001; Stracke, 2010; Devenish et al, 2009). Although, semi structured approaches have been developed and examined, informal learning opportunities have received minimal attention. The primary difference of Shut Up and Write! to other writing practices, is that individuals do not engage in any structured activity and they do not share the outcomes of the writing. The purpose of Shut Up and Write! is to transform writing practice from a solitary experience, to a social one. Shut Up and Write! typically takes place outside of formal learning environments, in public spaces such as a café. The structure of Shut Up and Write! sessions is simple: participants meet at a specific time and place, chat for a few minutes, then they Shut Up and Write for a predetermined amount of time. Critical to the success of the sessions, is that there is no critiquing of the writing, and there is no competition or formal exercises. Our case-study examines the experience of two meetup groups at RMIT University and QUT through narrative accounts from participants. These accounts reveal that participants have learned: • Writing/productivity techniques; • Social/cloud software; • Aspects of the PhD; and • ‘Mundane’ dimensions of academic practice. In addition to this, activities such as Shut Up and Write! promote peer to peer bonding, knowledge exchange, and informal learning within the higher degree research experience. This case-study extends the initial work presented by the authors in collaboration with Dr. Inger Mewburn at QPR2012 – Quality in Postgraduate Research Conference, 2012.
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The structure of Cu-ZSM-5 catalysts that show activity for direct NO decomposition and selective catalytic reduction of NOx by hydrocarbons has been investigated by a multitude of modern surface analysis and spectroscopy techniques including X-ray photoelectron spectroscopy, thermogravimetric analysis, and in situ Fourier transform infrared spectroscopy. A series of four catalysts were prepared by exchange of Na-ZSM-5 with dilute copper acetate, and the copper loading was controlled by variation of the solution pH. Underexchanged catalysts contained isolated Cu2+OH-(H2O) species and as the copper loading was increased Cu2+ ions incorporated into the zeolite lattice appeared. The sites at which the latter two copper species were located were fundamentally different. The Cu2+OH-(H2O) moieties were bound to two lattice oxygen ions and associated with one aluminum framework species. In contrast, the Cu2+ ions were probably bound to four lattice oxygen ions and associated with two framework aluminum ions. Once the Cu-ZSM-5 samples attained high levels of exchange, the development of [Cu(μ-OH)2Cu]n2+OH-(H2O) species along with a small concentration of Cu(OH)2 was observed. On activation in helium to 500°C the Cu2+OH-(H2O) species transformed into Cu2+O- and Cu+ moieties, whereas the Cu2+ ions were apparently unaffected by this treatment (apart from the loss of ligated water molecules). Calcination of the precursors resulted in the formation of Cu2+O2- and a one-dimensional CuO species. Temperature-programmed desorption studies revealed that oxygen was removed from the latter two species at 407 and 575°C, respectively. © 1999 Academic Press.
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FT Raman spectroscopy has been used to characterise the composition of the oxalate precursor to YBCO superconductors. By comparison to spectra of barium, copper and yttrium oxalate it is concluded that the co-precipitate incorporates not only the individual oxalate species but also a species ascribed to a mixed oxalate system. Significantly, Raman spectroscopy demonstrated that the precursor was not amorphous as previously deduced from XRD studies. In contrast, it is hypothesised that the sample consists of very small crystalline particles.