5 resultados para Sub-pixel techniques
em CiencIPCA - Instituto Politécnico do Cávado e do Ave, Portugal
Resumo:
Recently, regulating mechanisms of branching morphogenesis of fetal lung rat explants have been an essential tool for molecular research. The development of accurate and reliable segmentation techniques may be essential to improve research outcomes. This work presents an image processing method to measure the perimeter and area of lung branches on fetal rat explants. The algorithm starts by reducing the noise corrupting the image with a pre-processing stage. The outcome is input to a watershed operation that automatically segments the image into primitive regions. Then, an image pixel is selected within the lung explant epithelial, allowing a region growing between neighbouring watershed regions. This growing process is controlled by a statistical distribution of each region. When compared with manual segmentation, the results show the same tendency for lung development. High similarities were harder to obtain in the last two days of culture, due to the increased number of peripheral airway buds and complexity of lung architecture. However, using semiautomatic measurements, the standard deviation was lower and the results between independent researchers were more coherent
Resumo:
Recently, regulating mechanisms of branching morphogenesis of fetal lung rat explants have been an essential tool for molecular research. The development of accurate and reliable segmentation techniques may be essential to improve research outcomes. This work presents an image processing method to measure the perimeter and area of lung branches on fetal rat explants. The algorithm starts by reducing the noise corrupting the image with a pre-processing stage. The outcome is input to a watershed operation that automatically segments the image into primitive regions. Then, an image pixel is selected within the lung explant epithelial, allowing a region growing between neighbouring watershed regions. This growing process is controlled by a statistical distribution of each region. When compared with manual segmentation, the results show the same tendency for lung development. High similarities were harder to obtain in the last two days of culture, due to the increased number of peripheral airway buds and complexity of lung architecture. However, using semiautomatic measurements, the standard deviation was lower and the results between independent researchers were more coherent.
Resumo:
Este trabalho tem por objetivos analisar o disposto no POCAL (1999), na NICSP nº 17 do IPSASB (2006c), e na opinião de diversos autores, quanto ao reconhecimento dos heritage assets; bem como, verificar se poderão existir problemas inerentes ao reconhecimento dos heritage assets, na sub-região Minho-Lima, ultrapassáveis com a adoção das NICSP em Portugal. Do estudo efetuado, concluímos que o POCAL (1999) não apresenta os requisitos para o reconhecimento dos ativos. A NICSP nº 17 (IPSASB, 2006c) refere que, se a entidade reconhecer esses elementos como ativos, deve observar os requisitos para o reconhecimento dos ativos fixos tangíveis mencionados nessa norma. Atendendo também a que alguns dos municípios portugueses sentem dificuldades no reconhecimento dos heritage assets, concluímos que adotar um novo Sistema de Normalização Contabilística aplicável à Administração Pública (SNC-AP), assente nas NICSP, poderá ser a solução para ultrapassar tais dificuldades e garantir alguma comparabilidade da informação.
Resumo:
Este trabalho tem por objetivos analisar o disposto no POCAL (1999), na NICSP nº 17 do IPSASB (2006c), e na opinião de diversos autores, quanto ao reconhecimento dos bens do património, histórico, artístico e cultural (BPHAC); bem como, verificar se poderão existir problemas inerentes ao reconhecimento destes bens, na sub-região Minho-Lima, ultrapassáveis com a adoção das NICSP em Portugal. Do estudo efetuado, concluímos que o POCAL (1999) não apresenta os requisitos para o reconhecimento dos ativos. A NICSP nº 17 (IPSASB, 2006c) refere que, se a entidade reconhecer esses elementos como ativos, deve observar os requisitos para o reconhecimento dos ativos fixos tangíveis mencionados nessa norma. Atendendo também a que alguns dos municípios portugueses sentem dificuldades no reconhecimento dos bens do património, histórico, artístico e cultural, concluímos que adotar um novo Sistema de Normalização Contabilística aplicável à Administração Pública (SNCAP), assente nas NICSP, poderá ser a solução para ultrapassar tais dificuldades e garantir alguma comparabilidade da informação.
Resumo:
Background: Several studies link the seamless fit of implant-supported prosthesis with the accuracy of the dental impression technique obtained during acquisition. In addition, factors such as implant angulation and coping shape contribute to implant misfit. Purpose: The aim of this study was to identify the most accurate impression technique and factors affecting the impression accuracy. Material and Methods: A systematic review of peer-reviewed literature was conducted analyzing articles published between 2009 and 2013. The following search terms were used: implant impression, impression accuracy, and implant misfit.A total of 417 articles were identified; 32 were selected for review. Results: All 32 selected studies refer to in vitro studies. Fourteen articles compare open and closed impression technique, 8 advocate the open technique, and 6 report similar results. Other 14 articles evaluate splinted and non-splinted techniques; all advocating the splinted technique. Polyether material usage was reported in nine; six studies tested vinyl polysiloxane and one study used irreversible hydrocolloid. Eight studies evaluated different copings designs. Intraoral optical devices were compared in four studies. Conclusions: The most accurate results were achieved with two configurations: (1) the optical intraoral system with powder and (2) the open technique with splinted squared transfer copings, using polyether as impression material.