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Hajdek K.,University of Applied science Varazdin | Miljkovic P.,Media University | Modric D.,Getaldiceva 2
Tehnicki Vjesnik | Year: 2014

Better understanding of how internal structural changes affect the optical properties requires modelling the composite structure of a paper layer. We propose a Monte Carlo simulation platform, which allows different geometrical representations of the inner paper structure. Monte Carlo Modelling is a method that can be used to simulate photon interaction with substrate (in our case paper). The model can be built such that increasing complexity can be added as the model is being developed. Thus, the model is developed from a simple concept of random number generation to a very accurate interpretation of photon propagation in paper. We applied the model to the analysis of the effect of dot gain. The above model was used to analyse the effect of weight gain dot gain of printed lines of different thicknesses. The simulation results are in good agreement with measurements of reflection after having additionally introduced a filter function that permanently removes photons thereby adapting simulated values to the measured ones. Within the framework of the simulation, we can estimate the number of photons that ends below the screen element causing a possible increase of the optical dot gain. Source

Milkovic M.,University of Applied science Varazdin | Mrvac N.,University of Zagreb | Zjakic I.,University of Zagreb
Technics Technologies Education Management | Year: 2012

The paper analyzes the relationships and characteristics of the intensity of two related but different background visual effects (induction and assimilation) on the example of identical geometric patterns. If we consider that these background effects are directly determined by the characteristics of the spatial structure of the stimulus itself, it is obvious that by choosing identical samples the focus of the research primarily shifts on determining the impact of the choice of individual primary colors of additive and subtractive synthesis (as the basic design element) on the magnitude of the effect itself. Thus, for the research purposes, specific sets of patterns were created (Munker-White grid) that enable the intensity evaluation of both investigated effects in terms of change of perceived characteristics in relation to the physical (measured) colorimetric values on reproductions. The study results indicate that there are significant changes in the intensity of the investigated effects of identical geometric structures which are determined primarily and are dependent on the choice of color combinations that were used in the pattern design. Source

Modric D.,University of Zagreb | Maretic K.P.,University of Zagreb | Milkovic M.,University of Applied science Varazdin
Tehnicki Vjesnik | Year: 2012

Manufacturing significance of optical properties of paper motivated us to construct a theoretical approach which could be used to determine the reflection and dispersion of light from paper surface.We introduced a method based on the Monte Carlo model of light scattering in paper for better understanding the origin of optical screen values gain and to provide a more realistic description of the medium in which light scattering occurs. The Monte Carlo method was used as a frame within which we were able to describe the diffuse scattering of light which suffers multiple subsurface reflections. Our simulation provides a flexible and at the same time rigorous approach to the transport of light in a medium such as paper. We numerically investigated the effects of the modeled surface on the optical properties of paper throughout subsurface light scattering. Source

Maretic K.P.,Getaldiceva 2 | Milkovic M.,University of Applied science Varazdin | Modric D.,Getaldiceva 2
Tehnicki Vjesnik | Year: 2013

The analysis of the edge of the screen element is based on the selection of the linear sample on the paper - ink system in comparing models and reality. Although Yule and Nielsen suggested the Gaussian distribution for the description of the line spread function, our model, based on the stochastic approach of subsurface light scattering in paper, gives the complete description with the Lorentzian distribution. To determine which of the two proposed models, Gaussian or Lorentzian, gives a better approximation with respect to the measured data, Akaike information criterion has been used. As the observed profiles are asymmetric, both edges have been analyzed. It was not possible to distinguish which model better describes the resulting measurements, because of the extremely high value of the correlation coefficient for both models. Therefore the AIC method was applied using the routines in Origin 8.5 that was used to analyze the measured data. The Akaike weight demonstrates that the Lorentzian model better describes the LSF than the Gaussian model. Source

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