1000 resultados para Sign painting
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Drawing on the fields of philosophy, phenomenology, art history and theory as well as the candidate's own painting practice, this PhD explores the nature of ambiguity and semiosis in contemporary abstract painting. The thesis demonstrates how the aesthetic qualities of pause and rupture, transition and slippage work emergently to break established clichés, habits and intentions in the experiencing of abstract painting and artistic practice.
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Anatase TiO2 nanocrystals were painted on H-titanate nanofibers by using an aqueous solution of titanyl sulfate. The anatase nanocrystals were bonded solidly onto the titanate fibers through formation of coherent interfaces at which the oxygen atoms were shared by the nanocrystals and the fiber. This approach allowed us to create large anatase surfaces on the nanofibers, which are active in photocatalytic reactions. This method was also applied successfully to coat anatase nanocrystals on surfaces of fly ash and layered clay. The painted nanofibers exhibited a much higher catalytic activity for the photocatalytic degradation of sulforhodamine B and the selective oxidation of benzylamine to the corresponding imine (with a product selectivity >99%) under UV irradiation than both the parent H-titanate nanofibers and a commercial TiO2 powder, P25. We found that gold nanoparticles supported on H-titanate nanofibers showed no catalytic activity for the reduction of nitrobenzene to azoxybenzene, whereas the gold nanoparticles supported on the painted nanofibers and P25 could efficiently reduce nitrobenzene to azoxybenzene as the sole product under visible light irradiation. These results were different from those from the reduction on the gold nanoparticles photocatalyst on ZrO2, in which the azoxybenzene was the intermediate and converted to azobenzene quickly. Evidently, the support materials significantly affect the product selectivity of the nitrobenzene reduction. Finally, the new photocatalysts could be easily dispersed into and separated from a liquid because of their fibril morphology, which is an important advantage for practical applications.
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This study aims to explain the entrepreneurial processes as developments of entrepreneurial networks. As a theoretical framework, this study adopts the theory of experimentally organized economy and competence blocs. As suggested by this theory, entrepreneurs select profitable innovations and commercialise them. Through logistic regressions on the subjective and objective dependent variables, we find that nascent firms’ various activities to network customers, innovators, investors, and employees are positively associated with the business emergence. This study identifies the roles of entrepreneurs and the other actors in the entrepreneurial processes.
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At CRYPTO 2006, Halevi and Krawczyk proposed two randomized hash function modes and analyzed the security of digital signature algorithms based on these constructions. They showed that the security of signature schemes based on the two randomized hash function modes relies on properties similar to the second preimage resistance rather than on the collision resistance property of the hash functions. One of the randomized hash function modes was named the RMX hash function mode and was recommended for practical purposes. The National Institute of Standards and Technology (NIST), USA standardized a variant of the RMX hash function mode and published this standard in the Special Publication (SP) 800-106. In this article, we first discuss a generic online birthday existential forgery attack of Dang and Perlner on the RMX-hash-then-sign schemes. We show that a variant of this attack can be applied to forge the other randomize-hash-then-sign schemes. We point out practical limitations of the generic forgery attack on the RMX-hash-then-sign schemes. We then show that these limitations can be overcome for the RMX-hash-then-sign schemes if it is easy to find fixed points for the underlying compression functions, such as for the Davies-Meyer construction used in the popular hash functions such as MD5 designed by Rivest and the SHA family of hash functions designed by the National Security Agency (NSA), USA and published by NIST in the Federal Information Processing Standards (FIPS). We show an online birthday forgery attack on this class of signatures by using a variant of Dean’s method of finding fixed point expandable messages for hash functions based on the Davies-Meyer construction. This forgery attack is also applicable to signature schemes based on the variant of RMX standardized by NIST in SP 800-106. We discuss some important applications of our attacks and discuss their applicability on signature schemes based on hash functions with ‘built-in’ randomization. Finally, we compare our attacks on randomize-hash-then-sign schemes with the generic forgery attacks on the standard hash-based message authentication code (HMAC).
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This thesis narrates the professional learning experiences of seven Northern Territory teachers. It outlines the evolution from traditional professional development in schools to an active, responsive professional learning agenda. With increasing demands on teachers, standardisation and the quest for improved student outcomes, key themes in the re-storied narrative emerge about the definition and role of professional learning in complex conditions, effective teaching, quality programmes, and teacher agency. This thesis contributes to knowledge about the characteristics that teachers value in their professional learning experiences. An Ongoing Professional Enhancement Model (OPE) is proposed, highlighting directions in this field for key stakeholders.
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Intravenous immunoglobulin (IVIg) is widely used to treat autoimmune diseases. Several mutually nonexclusive mechanisms are proposed to explain the beneficial effects of IVIg in patients (1, 2). Lately, Ravetch and colleagues (3) demonstrate that anti-inflammatory activity of IVIg is mediated mainly by antibodies that contain terminal _2,6-sialic acid linkages at the Asn297-linked glycan of Fc region.
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This paper considers the one-sample sign test for data obtained from general ranked set sampling when the number of observations for each rank are not necessarily the same, and proposes a weighted sign test because observations with different ranks are not identically distributed. The optimal weight for each observation is distribution free and only depends on its associated rank. It is shown analytically that (1) the weighted version always improves the Pitman efficiency for all distributions; and (2) the optimal design is to select the median from each ranked set.
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The images in this exhibition were based on questioning relationships between the histories of painting and photography, which helped to establish the indexical references that became both photography’s most powerful attribute and most subtle illusion. Debates over the objectivity or subjectivity of the photograph and the uneasy relationship between painting and photography, as played out in the history of art, have been brought into sharp relief with the contemporary proliferation of digital images. The digital realm of photography gives rise to a general and relative skepticism of verity, but it can be argued that to artist/photographers, this representational malleability is precisely what their purpose becomes. In researching current issues of the indexical in photographic practice, landscape provides a potent vehicle for exploring issues of representation and illusion, the nexus of painting and photography, and the digital realm. One of contemporary photography’s most resonant themes is a return to pictorial subjects and methods, including a renewed interest in floribunda, still life and landscape. The resulting deconstruction and reconstruction of landscape ‘painting’ in this body of work- the monochrome, linear abstraction, painterly representationalsism and pictorialist detail is presented as a perceptual, aesthetic and digital act. The exhibition incorporates landscape painting’s simplicity and complexity, photography’s significance of representation and minimalist aesthetics in an over-mediated world.
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Digital Image
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Digital Image
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Digital Image
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Digital Image
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Digital Image