The aim of the study was to develop an assessment methodology for the temperature of the surface of the friction pair during the braking for mine hoists. During the braking process, the work of friction is transformed into heat at the level of friction surfaces, and in case high temperatures are reached, the friction coefficient is influenced negatively, thus the risk of braking failure exists. In the first part of the study we measured the temperature of the friction surfaces for a particular case of hoist in real braking conditions. In the second part of the study is presented a theoretical model for the calculation of the temperatures resulted in the braking process for the hoist equipped with shoe brakes. The theoretical model for calculation was simulated numerically for a particular case in real braking conditions. Based on the conclusions resulted after the study, a series of hypotheses and recommendations for adjusting the control of the process parameters have been given out, in order to avoid the excessive heating of the brakes of the hoists and, respectively, their improved safety, maintenance and availability.
In 1822 and 1838 two finds of late Roman solidi hoarded around AD 430/440 were unearthed at the Goldberg near Klein Tromp in former Eastern Prussia (now Trąbki Małe, Poland). With an approximate total of 141 gold coins confi rmed (including one aureus of Gordian III) this hoard represents the largest hoard of Roman solidi in Poland and the Baltic region to date. Most of the coins entered the Royal Cabinet in Berlin, while smaller parts were given to the University at Königsberg and the landowner. This article provides an overview of the history of the hoard’s discovery and later fate.
This study gives an analysis of the variation of main meteorological parameters on the Station Arctowski in the time from December 1979 through March 1980 — the summer season of the IV Antarctic Expedition of the Polish Academy of Sciences. Characteristics of wind speed and direction, of air temperature, atmospheric pressure, precipitation, cloudiness, soil temperature at the station and surface water temperatures of the Admiralty Bay are based on the standard synoptic observations.
This article aims to reconstruct Max Scheler’s conception of three types of knowledge, outlined in his late work Philosophical Perspectives (1928). Scheler distinguished three kinds of knowledge: empirical, used to exercise control over nature, eidetic (essential) and metaphysical. I review the epistemological criteria that underlie this distinction, and its functionalistic assumptions. In the article’s polemic part I accuse Scheler of a) crypto-dualism in his theory of knowledge, which draws insufficient distinctions between metaphysical and eidetic knowledge; b) totally omitting the status of the humanities in his classification of knowledge types; c) consistently developing a philosophy of knowledge without resort to the research tools offered by the philosophy of science, which takes such analyses out of their social and historical context (i.e., how knowledge is created in today’s scientific communities).
The article includes considerations and author’s proposals concerning the regional dimension of social policy. This aspect of social policy has not been investigated widely so far. The scope of regionalism and its forms are linked with the dominant social doctrine in a given country. They reflected in the ratio of territorial self-governments’ own incomes against those of the state budget, and in the institutional freedom they have in the area of benefit structuring, that is in decentralization. In the case of Poland, the political changes connected with the doctrinal ones hamper the development of regional social policy. This may have a negative impact on the coordination and implementation of social policy actions undertaken on different government levels and on the adjustment of social benefits to the needs of a region’s residents.
This paper deals with the experimental validation of the suitability of the method for measuring radial variations of components on the process tool. The tests were conducted using a computerized PSA6, which was compared to a Talyrond 73. The results of measurement of roundness deviations as well as roundness profiles were analyzed for a sample of 70 shafts. The roundness deviations were assessed by determining the experimental errors, while the profiles obtained with the tested device were compared to those registered by the reference device using three correlation coefficients.
The paper presents an analysis of the influence of elevated temperature on thin-walled purlins restrained by sheeting. In the first part of the study the bearing capacity of purlins cooperating with sheeting is examined in normal and elevated temperature based on European Standards. Next, special attention is paid to creating a numerical FEM model of the restrained purlins in Abaqus program taking into account different materials properties with respect to temperature increase.
Article published in Science, 2012 by Jennifer A. Doudna, Emmanuelle Charpentier and their team presented a novel tool named as CRISPR/Cas9. The original CRISPR/Cas9 tool and the whole system developed from it since then allow making precise changes in the nucleotide sequence in the defined locus of the genome. The article presents the already known as well the potential future applications of the system for improvement of cultivated plants. The separate section is devoted to present the background of the Court of Justice decision C-528/16. Discussed are the far reaching negative consequences of this, based not on the merit decision, for the future of European green biotechnology.