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A model for simulation of color vision deficiency and a color contrast enhancement technique for dichromats; Um modelo para simulação das deˇciências na percepção de cores e uma técnica de aumento do contraste de cores para dicromátas

Machado, Gustavo Mello
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
65.94%
As Deficiências na Percepção de Cores (DPC) afetam aproximadamente 200 milhões de pessoas em todo o mundo, comprometendo suas habilidades para efetivamente realizar tarefas relacionadas com cores e com visualização. Isto impacta significantemente os âmbitos pessoais e profissionais de suas vidas. Este trabalho apresenta um modelo baseado na fisiologia para simulação da percepção de cores. Além de modelar visão de cores normal, ele também compreende os tipos mais predominantes de deficiências na visão de cores (i.e., protanopia, deuteranopia, protanomalia e deuteranomalia), cujas causas são hereditárias. Juntos estes representam aproximadamente 99.96% de todos os casos de DPC. Para modelar a percepção de cores da visão humana, este modelo é baseado na teoria dos estágios e é derivado de dados reportados em estudos eletrofisiológicos. Ele é o primeiro modelo a consistentemente tratar visão de cores normal, tricromacia anômala e dicromacia de modo unificados. Seus resultados foram validados por avaliações experimentais envolvendo grupos de indivíduos com deficiência na percepção de cores e outros com visão de cores normal. Além disso, ele pode proporcionar a melhor compreensão e um feedback sobre como aperfeiçoar as experiências de visualização por indivíduos com DPC. Ele também proporciona um framework para se testar hipóteses sobre alguns aspectos acerca das células fotoreceptoras na retina de indivíduos com deficiência na percepção de cores. Este trabalho também apresenta uma técnica automática de recoloração de imagens que visa realçar o contraste de cores para indivíduos dicromatas com custo computacional variando linearmente com o número de pixels. O algoritmo proposto pode ser eficientemente implementado em GPUs...

A physiologically-based model for simulation of color vision deficiency

Machado, Gustavo Mello; Oliveira Neto, Manuel Menezes de; Fernandes, Leandro Augusto Frata
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
Português
Relevância na Pesquisa
65.92%
Color vision deficiency (CVD) affects approximately 200 million people worldwide, compromising the ability of these individuals to effectively perform color and visualization-related tasks. This has a significant impact on their private and professional lives. We present a physiologically-based model for simulating color perception. Our model is based on the stage theory of human color vision and is derived from data reported in electrophysiological studies. It is the first model to consistently handle normal color vision, anomalous trichromacy, and dichromacy in a unified way. We have validated the proposed model through an experimental evaluation involving groups of color vision deficient individuals and normal color vision ones. Our model can provide insights and feedback on how to improve visualization experiences for individuals with CVD. It also provides a framework for testing hypotheses about some aspects of the retinal photoreceptors in color vision deficient individuals.

Fuzzy Filtering Method for Color Videos Corrupted by Additive Noise

Ponomaryov, Volodymyr I.; Montenegro-Monroy, Hector; Nino-de-Rivera, Luis; Castillejos, Heydy
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Publicado em 06/02/2014 Português
Relevância na Pesquisa
25.63%
A novel method for the denoising of color videos corrupted by additive noise is presented in this paper. The proposed technique consists of three principal filtering steps: spatial, spatiotemporal, and spatial postprocessing. In contrast to other state-of-the-art algorithms, during the first spatial step, the eight gradient values in different directions for pixels located in the vicinity of a central pixel as well as the R, G, and B channel correlation between the analogous pixels in different color bands are taken into account. These gradient values give the information about the level of contamination then the designed fuzzy rules are used to preserve the image features (textures, edges, sharpness, chromatic properties, etc.). In the second step, two neighboring video frames are processed together. Possible local motions between neighboring frames are estimated using block matching procedure in eight directions to perform interframe filtering. In the final step, the edges and smoothed regions in a current frame are distinguished for final postprocessing filtering. Numerous simulation results confirm that this novel 3D fuzzy method performs better than other state-of-the-art techniques in terms of objective criteria (PSNR, MAE, NCD...

Developing a global soy blueprint for a safe secure and sustainable supply: proceedings.

WORLD SOYBEAN RESEARCH CONFERENCE, 8., 2009, Beijing.
Fonte: Beijing: Chinese Academy of Agricultural Sciences: Institute of Crop Science, 2009. WSRC 2009. Publicador: Beijing: Chinese Academy of Agricultural Sciences: Institute of Crop Science, 2009. WSRC 2009.
Tipo: Artigo em anais de congresso (ALICE) Formato: 1 CD-ROM.
Português
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Plenary sessions: The Argentine agroindustrial soy complex. Towards doubling soy protein intake in the Indian platter: what can the soy industry, policy makers and the civil society do? European soybean production and market: current situation and future trends. The status of soybean production and utilization in Southern Africa. A new approach of soybean improvement: hybrid soybean. New techniques induced from traditional soybean products and new technology of soybean process. The application of soybean for health and nutrition improvement of Chinese people. Progress of soybean disease research in a scenario of global changes and future challenges. The role and function of futures market in soybean industry development. Oral presentations: Germplasm: Genetic bases for effective in situ conservation of wild soybean (Glycine soja) germplasm. Gap analysis for soybean as an aid to complementary genetic conservation. Gene flow from GM soybean to wild soybean under field conditions: its implication in conservation. Collection, conservation, and evaluation of soybean germplasm. Conservation and management of soybean [Glycine max (L.) Merr.] genetic resources at National Gene Bank, New Delhi, India. Tolerance of soybean (Glycine max) germplasm from Southeast Asia to flooding stress. Nutritional...

Astronaut Jim Newman in space

Fonte: Rice University Publicador: Rice University
Tipo: photographs; Image
Português
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Astronaut Jim Newman appears to be inside of a space shuttle, with blue sky and clouds visible through the window above his head. He is wearing a blue Rice University tee-shirt that reads, "Rice, Physics in Space, Jim Newman, PH.D 1984. Space shuttle vision, STS-51". The NASA logo is printed to the left of the photograph, entitled "National Aeronautics and Space Administration, STS051-18-002, Lyndon B. Johnson Space Center, Houston, Texas 77058". Original resource is a color photograph.; James H. (Jim) Newman earned both a Master of Arts and Doctorate of Physics degree from Rice University in 1982 and 1984, respectively. Dr. Newman was appointed as adjunct professor in the Department of Space Physics and Astronomy at Rice - that same year, he began working at NASA's Johnson Space Center. He was working as a simulation supervisor when selected for the astronaut program. Photograph from Space Shuttle Discovery, STS-51 from September 12-22, 1993.

Malingering or simulation in ophthalmology-visual acuity

Incesu, Ali Ihsan; Sobacı, Güngör
Fonte: International Journal of Ophthalmology Press Publicador: International Journal of Ophthalmology Press
Tipo: Artigo de Revista Científica
Publicado em 18/10/2011 Português
Relevância na Pesquisa
35.75%
Simulation can be defined as malingering, or sometimes functional visual loss (FVL). It manifests as either simulating an ophthalmic disease (positive simulation), or denial of ophthalmic disease (negative simulation). Conscious behavior and compensation or indemnity claims are prominent features of simulation. Since some authors suggest that this is a manifestation of underlying psychopathology, even conversion is included in this context. In today's world, every ophthalmologist can face with simulation of ophthalmic disease or disorder. In case of simulation suspect, the physician's responsibility is to prove the simulation considering the disease/disorder first, and simulation as an exclusion. In simulation examinations, the physician should be firm and smart to select appropriate test(s) to convince not only the subject, but also the judge in case of indemnity or compensation trials. Almost all ophthalmic sensory and motor functions including visual acuity, visual field, color vision and night vision can be the subject of simulation. Examiner must be skillful in selecting the most appropriate test. Apart from those in the literature, we included all kinds of simulation in ophthalmology. In addition, simulation examination techniques...

Tests for malingering in ophthalmology

Incesu, Ali Ihsan
Fonte: International Journal of Ophthalmology Press Publicador: International Journal of Ophthalmology Press
Tipo: Artigo de Revista Científica
Publicado em 18/10/2013 Português
Relevância na Pesquisa
25.75%
Simulation can be defined as malingering, or sometimes functional visual loss (FVL). It manifests as either simulating an ophthalmic disease (positive simulation), or denial of ophthalmic disease (negative simulation). Conscious behavior and compensation or indemnity claims are prominent features of simulation. Since some authors suggest that this is a manifestation of underlying psychopathology, even conversion is included in this context. In today's world, every ophthalmologist can face with simulation of ophthalmic disease or disorder. In case of simulation suspect, the physician's responsibility is to prove the simulation considering the disease/disorder first, and simulation as an exclusion. In simulation examinations, the physician should be firm and smart to select appropriate test(s) to convince not only the subject, but also the judge in case of indemnity or compensation trials. Almost all ophthalmic sensory and motor functions including visual acuity, visual field, color vision and night vision can be the subject of simulation. Examiner must be skillful in selecting the most appropriate test. Apart from those in the literature, we included all kinds of simulation in ophthalmology. In addition, simulation examination techniques...

Simulação da visão das cores: decodificando a transdução quântica-elétrica; Simulation of the color vision: decoding quantum-electric transduction

Loreto, Élgion Lúcio da Silva; UFSM - Rio Grande de Sul; Sartori, Paulo Henrique dos Santos; UFRGS - Rio Grande do Sul
Fonte: Imprensa Universitária - UFSC Publicador: Imprensa Universitária - UFSC
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 25/08/2008 Português
Relevância na Pesquisa
45.74%
http://dx.doi.org/10.5007/2175-7941.2008v25n2p266Propomos uma simulação experimental, utilizando materiais acessíveis e de baixo custo, sobre o mecanismo biofísico da visão das cores em conformidade com a teoria tricromática de Young- Helmholtz, abordando, principalmente, o processo de codificação e decodificação de sinais elétricos que chegam ao córtex cerebral. O estímulo que desencadeia esse processo é dado via transformação da energia quantizada de um fóton de luz que ocorre nas fotocélulas da retina do olho humano. A construção de um sistema de coleta e análise de dados simples, utilizando basicamente um multímetro, filtros, LDR e LEDs, permite estabelecer conexões entre o sistema visual e o modelo de simulação.; We propose an experimental simulation, using accessible and low cost materials, on the biophysical mechanism of the color vision in accordance with the Young-Helmholtz s Trichromatic Theory, approaching mainly the coding and decoding process of electric signs that arrive to the cerebral cortex. The stimulus that unchains this process is given through transformation of the quantized energy of a light photon that takes place in the photocells of the retina of the human eye. The construction of a simple system of collection and analysis of data...