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Beanplot is a graphical method for visualizing univariate distributions. Density forecasts have an important role to play in many applications. Although graphical methods are widely used for illustrating distributions, suitable graphical methods to help for the purposes of analysis and comparison of density forecasters do not exist. This article explains how density forecasts and related observed densities are visualized parallel using beanplots in different groups of data. The visualization method is illustrated with industrial and simulated data. The functionality extends the plotting function of R package beanplot and the developed functions are made available for R programming language. [ABSTRACT FROM AUTHOR]

The purpose of this study was to develop a product design model for estimating the impact toughness of low alloy steel plates. The rejection probability in a Charpy V test is predicted with process variables and chemical composition. Joint modelling of the mean and deviation was used in order to improve the results. The proposed method is suitable for the whole production line, including all grades of steel in production and it is not restricted to a few test temperatures. Using the proposed model the product design group could have recognised most of the rejections before production. Next, the developed model will be implemented into a graphical simulation tool that is in daily use in the product planning department and already contains some other mechanical property models. The model will guide designers in predicting the related risk of rejection and in producing desired properties in the product at lower cost. [ABSTRACT FROM AUTHOR]

Not only the strength of steel but also the variance of strength depends on composition and thermomechanical treatments. Information about the variance of strength is important when composition and thermomechanical treatments are planned to fulfill the strength requirements. In this work, heteroscedastic linear models were used for joint modeling of the mean and dispersion of strength. The models were used as tools in the optimization of the strength margins for steel plate products. The models were created by using industrial process data, and they were successfully used in a steel plate mill. [ABSTRACT FROM AUTHOR]

In steel manufacturing, enormous amounts of data are gathered from many kinds of processes and it is difficult to distinguish useful knowledge from the resulting extensive databases. The recorded databases in the rolling process contain hundreds of features, and new methods are needed to reveal the novel and useful information. In the present study, the data from a hot strip rolling process were analysed in order to identify the rolling conditions in which some common defects, such as too thin or too narrow strip, do and do not occur. At the beginning, the dataset was reduced from its original size of over 200 features to 17% by using basic statistical analysis and linear correlation. After this, self-organising maps, parallel coordinates display, and k means clustering were used to find out the conditional probabilities of the common defect types. As a result, the method presented here revealed the rolling conditions for the four common defect types, i.e. coiling temperature close to the limits, too thin strip, too narrow strip, and torn tail end. Most important, the knowledge gained can be used to reduce the number of these defects. [ABSTRACT FROM AUTHOR]

An objective method is still lacking in the quantitative assessment of psoriasis severity. The purpose of this study was to examine whether computer image analysis (CIA) by a new colour segmentation method can be used as an objective method of estimating involved surface area in patients with psoriasis. Involved surface area in psoriasis was assessed from colour photographs covering the same areas as the psoriasis area and severity index (PASI) scores of 26 patients by human observers from different medical professional groups and by CIA. The reliability of CIA was tested with reference analysis by colouring manually the involved areas in the images with the aid of projected slides. The surface area estimates by the different methods were compared with each other and the resulting effects on the PASI score were assessed. The agreement between the reference analysis and the image analysis was high, especially on trunk areas, but the cylindrical shape of the limbs resulted in some difficulties in assessing involved skin area. The human eye estimates differed from the image analysis ones in almost one-third of (he cases and mostly when psoriasis affected under 30% of the skin surface area. Both over- and underestimates emerged, but overestimates were more common. Error estimates had a significant effect on the PASI score. The CIA method seems to be reliable and practicable in estimating the actual surface of psoriasis. The method has the disadvantage of being time-consuming (photographing, processing of pictures) and technically demanding. Further development of this method should make it faster in the future. [ABSTRACT FROM AUTHOR]

The lack of a quantitative method for assessing psoriasis severity poses a problem for quality control in dermatology. Quantitative estimation of involved surface area is important, as in the psoriasis area and severity index (PASI), but the reliability of many methods is poor. The purpose of this study was to assess the involved surface area of 15 psoriasis patients before and after different anti-psoriasis treatments using the human eye method and a computer image analysis (CIA) system based on colour segmentation. The human eye assessments were compared with the results of the CIA system and the resulting effects on the PASI score were also compared. The human eye estimates were higher than those obtained by the CIA method and, as a consequence, the values of the PASI by the human eye method were also higher than those by CIA. The human eye estimates differed most in cases where the PASI was under 15. The changes in the PASI by the human eye method before and after treatments differed significantly from those by CIA. The CIA system offers a possibility to quantify actual surface in patients with psoriasis, and will be an alternative for developing quality control when evaluating different treatment efficacies. [ABSTRACT FROM AUTHOR]