Simple camera calibration for light measurements
The availability and decreasing prices of digital photographic cameras using megapixel sensors could point to its use as high quality light measuring devices if simple and effective calibration procedures could be put to work. This paper proposes such a system, using a common digital camera combined with low cost reference color charts. The procedure to obtain the response function of the camera, the production of the color chart and its calibration is presented. In this way, it is possible to obtain light measurements otherwise only possible with sophisticated and expensive equipments.
Estimation of Neonatal Jaundice from the Chest Images Captured with a Smartphone
Hyperbilirubinemia is a common problem in neonatal for contact with the healthcare facilities. Several methods have been used to determine the bilirubin concentration. However, it is not easy to find the healthcare with the instrument to detect bilirubin, mainly in rural area. This research was aimed to develop a simple method for neonatal hyperbilirubinemia based on the chest images captured using a smartphone. A total of 31 randomly selected neonatal were studied, with the parental inform consent. The chest images have been capture using smartphone camera with the standard color chart besides the neonatal. The captured images were then analyzed by extracting the color intensity using ImageJ software. The bilirubin concentration obtained using standard method from the hospital were then analyzed to show the association of the chest color intensity with the bilirubin concentration. The result showed a high correlation between the blue color intensity and the blood bilirubin with the regression line of y = -0.466x + 162.84 (R = 0.851). The result of this study indicated the smartphone camera images of neonatal chest could be used for a simple screening tool of neonatal hyperbilirubinemia. Further study could be performed for smartphone software development of the bilirubin prediction from the neonatal chest images.
Finite Difference Modeling on the Temperature Field of Substrate in Friction Surfacing
Friction surfacing is an advanced process of great potential, especially in the field of repair and reclamation of worn and damaged components. As a kind of thermal processing technology, the temperature profile and changes of the substrate in friction surfacing are important factors to get coatings of high quality. In this paper, the temperature field of the substrate during the process is simulated by finite difference method. The results are consistent with experiments, reappearing the temperature change of the substrate during friction surfacing, allowing further study on figuration and quality of coatings.