Wire electrical discharge machining (WEDM) is a non-traditional technology utilized to manufacture parts of complex shapes or machining the materials conventionally difficult to process. It is also applied in the aerospace industry, where Inconel 625, which was the subject of the research in this study based on aDesign of experiment (DoE), is usually machined. In this way, the experiment contained 33 rounds during which the settings of machined parameters were changed systematically. An identical experiment (33 rounds) was performed in which the semi-finished product was rotated by 90° to define the impact of the orientation direction of the cut on the speed of cutting and the quality of the surface and subsurface layers. Subsequently, a complex analysis of the machined surfaces of the individual samples was performed, including both the surface and subsurface layers. Topography was evaluated using a non-contact profilometer, including the creation of a color-filtered 3D surface relief. The subject of further investigation was the analysis of morphology and surface defects including the chemical composition analysis. For a very detailed observation of the distribution of the individual elements in the material, lamella was prepared, which was subsequently studied using a Transmission Electron Microscope (TEM). For the subsurface layer study and its defects, metallographic preparations of all samples, which were observed using both light and electron microscopy, were prepared. On the basis of the analyses performed, the impact of the cutting direction on the cutting speed as well as the machined surface quality was determined.

Geographical and botanical origin of honeys can be characterized on the basis of physico-chemical composition, sensory properties and on the basis of melissopalynological analysis. No comprehensive description of the characteristics of Czech honey has been published so far. This study provides insights that are important for correct classification. The study analysed 317 samples of authentic honey from randomly selected localities. Due to the diversity of the landscape, the typical honey of the region is blend honey with a predominance of blossom honey. According to the pollen profile and electric conductivity, the honeys were sorted into the following: Brassica honey (BH), Floral honey (FH), Fruit tree honey (PH), Honeydew (HD), Lime tree honey (LH), Robinia pseudoacacia honey (RH), and Trifolium honey (TH). Physico-chemical properties, including higher carbohydrates, were determined for the honeys and their pollen profiles were examined. The physico-chemical properties and pollen profile are partially in compliance with the description of European monofloral honeys, except for RH and TH. Although they had the highest proportion of acacia pollen, amounting to >10% of all the Czech honeys, these RH honeys differ from the European standard, so they cannot be considered acacia honey. Further, PH honeys and FH polyfloral honeys were described. Most honeys contained a significant proportion of rapeseed pollen, which is one of the common agricultural crops grown in the Czech Republic. All the analysed honeys met the parameters defined by the legislation. Due to direct on-site sampling, honeys were characterized by a low 5-(hydroxymethyl)furfural (HMF) content (3.0 mg/kg) and high diastase activity (24.4 DN). Honeydew honeys had the highest proportion of higher carbohydrates, primarily of Melezitose (4.8 g/100 g) and Trehalose (1.3 g/100 g). The presence of higher carbohydrates was also confirmed in LH for Maltose (4.6 g/100 g) and Turanose (2.4 g/100 g).

Wire electrical discharge machining is an unconventional machining method for the production of complex-shaped and very precise parts. Because of the high energy consumption of this machining process, it is necessary to maximize the cutting speed for its appropriate implementation. The abrasion-resistant steel Creusabro 4800 was chosen as the test material for this experiment, which is widely used especially for machines working in mines and quarries. In order to maximize the cutting speed, a fuzzy inference system (FIS) has been built, which uses 18 expert propositions to “model” the cutting speed based on five selected input parameters: gap voltage, pulse on time, pulse off time, discharge current, and wire feed. The obtained results were further verified by a design of experiment consisting of 33 tests for five selected input factors. Using the fuzzy inference system, the optimum machine parameters setup was found to maximize the cutting speed, in which the gap voltage = 60 V, pulse on time = 10 µs, pulse off time = 30 µs, wire feed = 10 m∙min⁻¹ and discharge current = 35 A. The predicted value of the cutting speed using the fuzzy inference system is 6.471 mm∙min⁻¹.