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The paper presents the software procedure (using MAPLE 11) intended for considerable reduction of digital image data set to more easily treatable extent. The example with image of peach stone is presented. Peach stone, displayed on the digital photo, was represented as a polygon described by the coordinates of the pixels creating its perimeter. The photos taken in high resolution (and corresponding data sets) contain coordinates of thousands of pixels - polygon's vertexes. Presented approach substitutes this polygon by the new one, where smaller number of vertexes is used. The task is solved by use of adapted least squares method. The presented algorithm enables reduction of number of vertexes to 10 % of its original extent with acceptable accuracy +/- one pixel (distance between initial and final polygon). The procedure can be used for processing of similar types of 2D images and acceleration of following computations.

In general, the over sea height is cumulative factor, which can influence significantly the farm conditions. This effect consists of temperature (mean year temperature), rain (sum of rainfulls), sunshine (total period of sunshine) and so on, in terms of climate, which can influence the dairy cow keeping directly and indirectly. Direct effects can influence the welfare of dairy cows in terms of hot stress for example, which could decrease a mastitis resistance of cows or their milk yield in simply way. Indirect effects can influence the dairy cows and their milk production (milk yield and milk composition and quality) by typical kinds of forages and preserved rough fodders, by their botany composition and nutritional quality. In general it is possible to say, that increasing over sea height decreases economical efficiency of dairying. On the other hand the higher over sea height is sometimes linked with pastoral system of dairy cow rearing and nourishment and more often with possibility to ecological and biodynamical agriculture application. In the fact, the mountain and submountain localities are named as less favourable areas (LFAs) in terms of agriculture efficiency and sustainability under the Czech Republic conditions. Despite of above mentioned facts, the pastoral system of dairying plays very important role for tourism development in different countries such as Alpine or Scandinavien countries, Ireland, The Netherlands or in particular in New Zealand.
It could be very good to know the incidentaly possible impacts of over sea height of dairy cow rearing localities on milk quality, composition and its technological properties because of discussions about incidental dairy subsidies. Of course, in some countries including the Czech Republic, the governmental production subsidies or governmental environmental subsidies are partly linked with over sea height of localities of dairy farms, according to different calculation formulas as well.
The individual milk samples, feedstuff samples (total mixed ration (TMR) on feeding trough) and mean excrement samples were collected at seven dairy cow herds and two main milked breeds of cattle (in the CR) for three years. Bulk milk samples were collected as well. It was done two times per year in winter (February, Marz) and summer (August, September) seasons. The herds were localised in lowland (N; ≤ 350 m of o.s.h.) and highland (P; > 350 m of o.s.h.) areas. The breed effect (H = Holstein and C = local Bohemian spotted cattle based on Simmental breed) was good balanced between N and P areas. The milk yields of herds varied from 5500 to 10000 kg of milk per lactation. The different but typical varieties of nourishment and feeding systems of dairy cows were applied in the herds: N = alfalfa silage with maize silage; P = clover-grass silage, grass silage with maize silage and grass pasture as well. The concentrates were feeded according to milk yield and nutrition demand standards.
Investigated chemical-compositional, physical, health and technological parameters in individual milk samples were as follows: daily milk yield (ML; kg of milk per day); fat content (Tuk; g/100ml); lactose content (Lak; g/100g of monohydrate); solids non fat (STP; g/100g); somatic cell count (PSB; tis./ml); urea content (Mo; mg/100ml); acetone

Presented work focuses on bending moment stress modeling of dismountable furniture joints with a use of Finite Element Method. The joints are created from Minifix and Rondorfix cams combined with non-glued wooden dowels. Laminated particleboard 18 mm of thickness is used as a connected material. The connectors were chosen such as the most applied kind in furniture industry for the case furniture. All gained results were reciprocally compared to each other and also in comparison to experimental testing by the mean of stiffness. The non-linear numerical model of chosen joints was successfully created using the software Ansys Workbench. The detailed analysis of stress distribution in the joint was achieved with non-linear numerical simulation. A relationship between numerical simulation and experimental testing was showed by comparison stiffness tangents. A numerical simulation of RTA joint loads also demonstrated the important role of non-glued dowels in the tested joints. The low strength of particleboard in the tension parallel to surface (internal bond) is the most likely the cause of the joint failure. Results are applicable for strength designing of furniture with the aid of Computer Aided Engineering.