Universal Dependencies (UD) je mednarodno usklajena označevalna shema za medjezikovno primerljivo oblikoslovno in skladenjsko označevanje besedil po načelih odvisnostne slovnice, ki je bila ob več ...kot 130 drugih svetovnih jezikih uspešno uporabljena tudi za označevanje besedil v slovenščini. V prispevku predstavimo rezultate nedavnih aktivnosti v povezavi s shemo UD znotraj projekta Razvoj slovenščine v digitalnem okolju, v okviru katerega smo obstoječo infrastrukturo nadgradili s prenovo in podrobno dokumentacijo označevalnih smernic UD za slovenščino, razširitvijo drevesnice SSJ-UD za pisno slovenščino z novimi povedmi iz korpusov ssj500k in ELEXIS-WSD, izdelavo testne množice iz besedil korpusa SentiCoref za spletni portal SloBENCH ter polavtomatsko pretvorbo oblikoslovnih oznak referenčnih učnih korpusov SUK in Janes-Tag. Na razširjeni drevesnici SSJ-UD je bil naučen tudi novi napovedni model za skladenjsko razčlenjevanje v orodju CLASSLA-Stanza, ki ga v prispevku v podporo nadaljnjim jezikoslovnim aplikacijam podrobneje ovrednotimo z vidika splošne natančnosti razčlenjevanja in najpogostejših tipov napak.
Electrochemical micromachining (ECMM) is a well know for manufacturing hard-to-cut materials, e.g., nickel-based alloys, titanium alloys and metal-matrix composites. For this reason it finds ...application in aerospace, automobile and biomedical industries. In this research Hastelloy C-276 is used as a workpiece and stainless-steel electrode coated with polytetrafluoroethylene (PTFE) to avoid stray current. The effect of process parameters such as voltage, duty cycle and electrolyte concentration on the machining speed and the surface-corrosion factor were studied. The range of 9–11 V has an impact on the machining speed. The electrolyte concentration range of 25–35 g/L shows a linear increase in the machining speed and the surface-corrosion factor is found to be highest at 1.1449 for an electrolyte concentration of 15g/L. The surface roughness depth profile depicts the values of Rz, Rt, Ra are 16.3 µm, 99.1 µm and 1.90 µm, and 15.4 µm, 50.6 µm and 1.49 µm, respectively.
The aim of our study was to investigate how different thermal conditions affect the transformation temperatures of two hot-work steels with high thermal conductivity. We focused on two conditions: ...soft annealing, and quenching and tempering. Soft annealing results in a ferritic steel matrix with spherical carbides, while quenching and tempering result in a fully hardened and tempered martensitic matrix with secondary and tempering carbides. We analysed samples using a simultaneous thermal analysis (STA) and differential scanning calorimetry (DSC) to determine the transformation temperatures. Controlled heating and cooling allowed us to observe the energy changes associated with the phase transformations. The equilibrium temperatures were calculated using the CALPHAD method. Our study investigated the influence of thermal conditions on different transformation temperatures, including solidus/liquidus temperatures, austenite solid transformation temperatures (A1 and A3), austenite solidification temperatures and bainite and/or martensite transformation temperatures. A DSC analysis was used to quantitatively measure the transformation temperatures and energy absorption during the endothermic processes (austenite solid transformation and melting) and to study the energy release during the exothermic processes (solidification and transformation). The results showed that soft annealing reduced the solidification interval and the solidus temperature, while energy absorption increased during melting. Conversely, quenching and tempering reduced the austenite solid transformation temperatures and energy release during solidification, including δ-ferrite solidification.
Electrical discharge machining is an electro-thermal technique where the recast layer on a machined surface and the heat-affected zone (HAZ) immediately below the machined surface are prevalent. As a ...result, assessing the white layer (recast layer) in EDM is a critical task. In this research, a response-surface methodology-based comprehensive mathematical model was developed to predict the white-layer thickness (WLT) on electrical discharge machine-processed AISI A2 steel. Also, the effects of various process parameters on the WLT were presented, the optimum combination of process variables was assessed and the minimum WLT was achieved by combining low-peak current and pulse-on time with high pulse-off time.
Electrical discharge machining (EDM) is much preferred in modern precision-manufacturing industries owing to its ability to machine any metal regardless of its hardness. However, its constraint is ...that the selected metal should be an electrically conductive material. For the present investigation, an Inconel 718 alloy was selected for EDM, using a TiB2-Cu electrode made with powder metallurgy. Input factors, namely, the pulse current (Ip), pulse-on time (Ton) and gap voltage (Gv) were selected and their output responses were the surface roughness (SR) and material-removal rate (MRR). For the response surface, the Box Behnken technique was preferred when designing the experiments (DoE). An ANOVA test was performed to understand the influence of the selected input factors on the SR and MRR. The RSM integrated with a grey relational analysis (GRA) revealed that the optimal input parameters for better machining characteristics were: Ip = 10 A, Ton = 40 µs and Gv = 50 V. Besides, the results also showed that the pulse current more significantly influenced the output responses than the other parameters. Moreover, an increase in the gap voltage caused surface irregularities on the machined surface. Surface morphology of the machined surfaces was analysed through SEM and EDAX. Moreover, a certain amount of tool-material transfer was noted with the EDAX analysis.
The high-temperature oxidation behaviour of chromium-molybdenum-vanadium alloyed hot-work tool steel was investigated. High-temperature oxidation was investigated in two conditions: soft annealed, ...and quenched and tempered. The samples were oxidised in a chamber furnace and in an instrument for simultaneous thermal analysis, for 100 h in the temperature range between 400 °C and 700 °C. Metallographic analysis (optical and scanning electron microscopy) was performed to study the microstructural changes in the steel and the oxide layer. Oxidation kinetics were analysed by thermogravimetric analysis, and equations were derived from the results. The kinetics can be described by three mathematical functions, namely: exponential, parabolic and cubic. However, which function best describes the kinetics depends on the oxidation temperature and the thermal condition of the steel. Quenched and tempered samples were shown to oxidise less, resulting in a slower oxidation rate.
Long-term field experiment to follow various effects of conservation soil tillage is conducted at Biotechnical faculty in Ljubljana. The soil is Eutric Gleysol. Conventional treatment with plowing, ...22 cm deep P, and conservation treatment by rotary harrow to a depth of 10 cm N, and subplots with compost amendment (-c) and without fertilization (-n) were observed. After 5 years nutrient contents and organic matter were higher in N than P. Compost addition had a positive effect on microbial biomass, but the tillage system did not affect it. However, nitrogen mineralization and decomposition of straw were higher in P as in N, and in the soil depth of 15 - 20 cm than in the 5 - 10 cm.
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