Stress concentration factors (SCFs) at welded tubular joints are one of the prime factors that affect the fatigue life of a structure. In the present work, finite element analysis (FEA) is used to find the hot spot stress and subsequently the stress concentration factors of Tubular T/Y steel Joints. Static axial tensile loading case is used in the present work. The circular hollow sections (CHS) are considered. The parametric study of the variation in SCF, with the change in joint angle (ϴ) and geometrical parameters such as β, τ, γ for T/Y-Joints subjected to inplane axial loading, is done. The validation of FE modelling technique of present work is done by comparing with the various SCFs equations available in the literature

The aim of the research was to define the influence of treatment methods, with the use of growth biostimulators and herbicide on the yield structure of three varieties of edible potato. The series of field research was carried out in the years 2015-2017, in the region of eastern Poland, in Biała Podlaska municipality, in Lubelskie voivodship, on light, acidic soil. The experiment was constructed with the use of random sub-blocks method in three repetitions. The tested factors included: I. factor-three early edible potato varieties Owacja, Bellarosa, Vineta; II. factor-five methods of treatment of the field of potato crops with the use of growth biostimulators: GreenOk-Uniwersal Pro and Asahi SL and their combinations with Avatar 293 ZC herbicide. As a result of the conducted research it was found that the methods of treatment with the use of growth biostimulators and herbicide had a positive effect on the structure of potato tuber yields, compared to the standard object on which only mechanical care was applied. The highest weight percent of large tubers input (in fractions >51mm) was observed in case of experimental object 4. (in case of which herbicide Avatar 293 ZC and GreenOK Universal-PRO preparation were applied) as well as experimental object 3 (post applying biostimulator Asahi SL). Varieties cultivated in the experiment had a significant impact also on the structure of potato crops. An impact of weather conditions on the structure of potato tubers was further noted. Based on the conducted experiment, it can be concluded that the growth biostimulators, as well as their combination with herbicide, positively influenced the quality parameters of potato tubers. Therefore, these preparations should find wider application in agricultural practice.

Abstract. Each oval and a natural number n ≥ 3 generate an annulus which possesses the Poncelet's porism property. A necessary and sufficient condition of existence of circuminscribed n-gons in an annulus is given.1. Introduction. Let C be an oval, i.e. a plane simple closed curve with a positive curvature, see [4]. We will consider C in the formwhere p is a fixed support function (the dot denotes the differentiation with respect to t). The function R = p +p is the radius of curvature of C, see [6]. We associate with a fixed oval C a family P (C) = {C m : m > 0} containing all parallel curves C m to C; the support function p m of C m is given by the formulaMoreover, we associate with C a second family I (C) = {C α : 0 < α < π} where C α is an α-isoptic of C. We recall that C α is a locus of vertices of a fixed angle π − α formed by two support lines of the curve C, see [3].2000 Mathematics Subject Classification. 53A04.

The test of concrete compressive strength conformity with current regulations PN EN 206-1:2003 is the sampling inspection based on a numerical evaluation. Satisfying the compound criteria, including the adoption of statistical quality control plan, confirms the conformity of the examined batch of concrete defined by the declared class of compressive strength defined by characteristic value of compressive strength. The conformity criteria recommended by EN 206-1 for the initial production are not without flaws and they are critically evaluated by many authors. This paper presents a new criterion of conformity based on order statistics. A preliminary evaluation of the criterion was made for the series with a small number of the test results with the use of probability of acceptance determined by means of the Monte Carlo method with the assumed 5% fraction defective. The analysis of the results showed that the presented criterion does not depend on the dispersion of results whereas the probability of acceptance is maintained at a constant level approached to the appropriate one at the stage of continuous production.

New solutions which would allow for the realization of two basic objectives, i.e. production-related and environmental ones, continue to be sought in plant production. Hence, the purpose of research was to define the impact of five methods of potato field treatment with the application of growth biostimulators and herbicide on the content and harvest of major protein Solanum tuberosum L. Field experiments were carried out in the years 2015-2016 in the region of Eastern Poland (52°02'N; 23°07'E). The experiment was performed in the split-plot system in three replications. The tested factors included: I. Factor-two early edible potato cultivars (Owacja, Bellarosa), II. Factor-methods of treatment with the application of growth biostimulators: GreenOk-Uniwersal Pro and Asahi SL and their combination with Avatar 293 ZC herbicide. As a result of the carried out research, it was noted that the methods of treatment applied in the experiment had a beneficial effect on the value of tested features in comparison to the control object, treated exclusively mechanically (without the use of biostimulators and herbicide). Both in terms of protein concentration and the obtained crop of major protein, the application of mechanical treatment for sprouting of potato plants and Avatar 293 ZC herbicide at a dose of 1.5 dm 3 •ha-1 directly before the sprouting and subsequently post sprouting, triple application of GreenOK Universal-PRO bioactivator at the following doses: 0.10 dm 3 •ha-1 + 0.15 dm 3 •ha-1 + 0.15 dm 3 •ha-1 was the most beneficial. The average content of major proteins in this object amounted to 8.14% while the average protein yield-750.09 kg•ha-1 .