535 resultados para HD8085.P6 P6 vol.5


Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this paper, a novel pattern recognition scheme, global harmonic subspace analysis (GHSA), is developed for face recognition. In the proposed scheme, global harmonic features are extracted at the semantic scale to capture the 2-D semantic spatial structures of a face image. Laplacian Eigenmap is applied to discriminate faces in their global harmonic subspace. Experimental results on the Yale and PIE face databases show that the proposed GHSA scheme achieves an improvement in face recognition accuracy when compared with conventional subspace approaches, and a further investigation shows that the proposed GHSA scheme has impressive robustness to noise.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this paper, a new blind and readable H.264 compressed domain watermarking scheme is proposed in which the embedding/extracting is performed using the syntactic elements of the compressed bit stream. As a result, it is not necessary to fully decode a compressed video stream both in the embedding and extracting processes. The method also presents an inexpensive spatiotemporal analysis that selects the appropriate submacroblocks for embedding, increasing watermark robustness while reducing its impact on visual quality. Meanwhile, the proposed method prevents bit-rate increase and restricts it within an acceptable limit by selecting appropriate quantized residuals for watermark insertion. Regarding watermarking demands such as imperceptibility, bit-rate control, and appropriate level of security, a priority matrix is defined which can be adjusted based on the application requirements. The resulted flexibility expands the usability of the proposed method.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper is concerned with the universal (blind) image steganalysis problem and introduces a novel method to detect especially spatial domain steganographic methods. The proposed steganalyzer models linear dependencies of image rows/columns in local neighborhoods using singular value decomposition transform and employs content independency provided by a Wiener filtering process. Experimental results show that the novel method has superior performance when compared with its counterparts in terms of spatial domain steganography. Experiments also demonstrate the reasonable ability of the method to detect discrete cosine transform-based steganography as well as the perturbation quantization method.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper investigates the application of complex wavelet transforms to the field of digital data hiding. Complex wavelets offer improved directional selectivity and shift invariance over their discretely sampled counterparts allowing for better adaptation of watermark distortions to the host media. Two methods of deriving visual models for the watermarking system are adapted to the complex wavelet transforms and their performances are compared. To produce improved capacity a spread transform embedding algorithm is devised, this combines the robustness of spread spectrum methods with the high capacity of quantization based methods. Using established information theoretic methods, limits of watermark capacity are derived that demonstrate the superiority of complex wavelets over discretely sampled wavelets. Finally results for the algorithm against commonly used attacks demonstrate its robustness and the improved performance offered by complex wavelet transforms.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Companion piece to my earlier article in Literature Conmpass: 'Modern Problems of Editing: The Two Texts of Doctor Faustus'. Provides a model for a module based on the topic of that article.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This study investigates face recognition with partial occlusion, illumination variation and their combination, assuming no prior information about the mismatch, and limited training data for each person. The authors extend their previous posterior union model (PUM) to give a new method capable of dealing with all these problems. PUM is an approach for selecting the optimal local image features for recognition to improve robustness to partial occlusion. The extension is in two stages. First, authors extend PUM from a probability-based formulation to a similarity-based formulation, so that it operates with as little as one single training sample to offer robustness to partial occlusion. Second, they extend this new formulation to make it robust to illumination variation, and to combined illumination variation and partial occlusion, by a novel combination of multicondition relighting and optimal feature selection. To evaluate the new methods, a number of databases with various simulated and realistic occlusion/illumination mismatches have been used. The results have demonstrated the improved robustness of the new methods.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This article compares two documentary treatments of the Central Park vigil for John Lennon in 1980: Happy Birthday to John (Jonas Mekas, 1995, 16mm, 18 min.), and Dix minutes de silence pour John Lennon/Ten Minutes Silence for John Lennon (Raymond Depardon, 1980, 16mm, 10 min.). Mekas and Depardon might seem an improbable combination but as the article demonstrates there are affinities, if not direct points of convergence, in outlook and documentary method: both sensibilities have been shaped by migrant experiences, and much of their work, for all its formal and structural differences, is preoccupied with experiences of exile and displacement, rootedness and the meaning of home, the country and the city (and in Mekas’s case, the country in the city). Mekas and Depardon are also Europeans who have developed an intimate social and artistic relationship with New York City; both are concerned with the place of autobiography in their work, using captions, inter-titles, diary entries, photographs, and 1st person commentary to complicate relations between the imaginary and the documentary. In addition to discussing the significance of these preoccupations, and differences in the manner in which both filmmakers witness the apotheosis of Lennon as cultural martyr (and natural New Yorker), the article also examines the phenomenon of public mourning, and how it often displaces its ostensible subject: associatively, in the case of Mekas; incidentally, in the case of Depardon; and intentionally, in the case of the mass media, and popular culture.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

China has been the world’s fastest growing economy in the past 30 years with its enterprises rapidly emerging and becoming leading players globally. In particular, the progressive integration into the international system has been spurred by China’s entry into the global trading regime of the World Trade Organization (WTO) in 2001. The 'go global' policy has been facilitating the rapidly growing engagement on the African continent of Chinese multinational companies (MNCs). As a promising tri-polar global economic entity, its growth of relations with Africa has been both unprecedented and impressive. As the Sino-Africa economic and business partnership surges forward, the matter of corporate social responsibility (CSR) is increasingly becoming an imperative ingredient for any successful business. It is noteworthy that responsible corporate citizens should take account of the impact of their investment on both economic and social arenas. However, it still remains uncertain what role Chinese MNCs have been playing in the continent’s sustainable development.
A Sino-Congo deal seems a positive way forward, accelerating the Democratic Republic of Congo’s (hereinafter referred to as Congo) regional economy, depressed due to years of war. Meanwhile, the escalating investment into Congo has raised controversies for its no-attachment policy, with increasing pressure imposed on China’s MNCs to take CSR more seriously. Particular concerns are focused on the multinationals’ inadequate environmental and human rights protection. The recent massive infrastructure investment is arguably perceived as a different interpretation of CSR, which has aroused a hot debate about whether China is heading for status as a responsible stakeholder in the international community. It is conducive to clarifying the paradoxical issue by addressing whether China’s recent approaches have the potential to facilitate CSR initiatives or hinder them in the long run.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper focuses on the question of whether the UNHCR should be governed only by its original 1950 mandate to provide international protection to refugees or should its role be re-defined in order to cover those who are not refugees, yet in refugee-like conditions. The purpose of this study is to scrutinize what rights UNHCR already possesses with regards to its newly-evolved tasks and what sort of legal framework is required today.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background: Erythropoiesis stimulating agents (ESAs) are widely used to treat anaemia but concerns exist about their potential to promote pathological angiogenesis in some clinical scenarios. In the current study we have assessed the angiogenic potential of three ESAs; epoetin delta, darbepoetin alfa and epoetin beta using in vitro and in vivo models.

Methodology/Principal Findings: The epoetins induced angiogenesis in human microvascular endothelial cells at high doses, although darbepoetin alfa was pro-angiogenic at low-doses (1-20 IU/ml). ESA-induced angiogenesis was VEGF-mediated. In a mouse model of ischaemia-induced retinopathy, all ESAs induced generation of reticulocytes but only epoetin beta exacerbated pathological (pre-retinal) neovascularisation in comparison to controls (p<0.05). Only epoetin delta induced a significant revascularisation response which enhanced normality of the vasculature (p<0.05). This was associated with mobilisation of haematopoietic stem cells and their localisation to the retinal vasculature. Darbepoetin alfa also increased the number of active microglia in the ischaemic retina relative to other ESAs (p<0.05). Darbepoetin alfa induced retinal TNF alpha and VEGF mRNA expression which were up to 4 fold higher than with epoetin delta (p<0.001).

Conclusions: This study has implications for treatment of patients as there are clear differences in the angiogenic potential of the different ESAs.