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EN
The article discusses the methods of studying prehistoric flint mines presented in the book 'Metody badan archeologicznych stanowisk produkcyjnych - górnictwo krzemienia' (Methods used in the archaeological study of production sites - flint mining), published in Warsaw in 2000. The author of the article is generally critical of the work, though certain fragments are praised. He considers its greatest failings to be the marginal discussion of flint material from the mines, a lack of suggestions for rescue excavations of flint mines and the viewing of prehistoric mining solely from the perspective of modern industrial mining. In the conclusion the article mentions the need for a monograph covering the many years of research done at the Krzemionki Opatowskie flint mine site. Summary The article discusses the methods of researching pre­historic flint mines as presented in the book 'Metody badan archeologicznych stanowisk produkcyjnych - górnictwo krzemienia' (Methods of archaeological research of production sites - flint mining), published in 2000 The book comprises eleven articles by nine authors. The foremost articles are written by a team of archaeologists who, since the early 1980s, have been studying the flint mine at Krzemionki Opatowskie (W. Borkowski, W. Migal, S. Salacinski, M. Zalewski) and by J. Budziszewski, who has studied the mine at Ozarów in central Poland. The book is in Polish, without an index and foreign language summaries or abstracts. Even translation of the title and contents are lacking. The author of the article points to weaknesses both in the editorial concept of the book as a whole and of individual articles. He notes that some of them are superfluous - such as the one devoted to the magnetic and electromagnetic methods, which have no practical application in the exploration of flint mines. Other articles present the use of outdated tools and software. On the other hand, the work lacks a much needed article on methods of determining the chronology of flint mines and the danger of committing characteristic errors. The author is also very critical of the examples of drawings of shaft profiles proposed by the authors, and of the photographic documentation which is of poor quality and often without any scale. The well written parts of the book include the fragments devoted to surface examination of flint mine sites and to analysis of filling from shaft I/4 at Ozarow (J. Budziszewski), also to the study of the structure of rubble dumps in the underground mine chambers at Krzemionki Opatowskie (W. Migal), to the model of distribution of flint exploitation systems at the Krzemionki mining field (W. Borkowski) and to the application of the resistivity method in studies of flint mines (T. Herbich). The greatest inadequacies of the book are the marginal treatment of the geology of the excavated mine sites, of the methods of studying structures and flint material from the mines, the lack of suggestions as to rescue excavations of flint mines, the treatment of prehistoric flint mining solely from the perspective of the history of modern industrial mining without taking into consideration the prehistoric context. The reviewer also notices the careless use and compilation of literature in most of the articles as well as a number of other errors. He also recalls that similar weaknesses were pointed out ten years ago by B. Balcer in his review of the first book published by the same team from the State Archaeological Museum in Warsaw.
PL
Najwygodniejszym i najszybszym środkiem poruszania się po mieście jest samochód osobowy. Jego przewaga nad innymi środkami komunikacji maleje wraz ze wzrostem natężenia ruchu samochodowego na ulicach i tworzeniem się tak nie lubianych, acz coraz częstszych korków. Zniechęceni tymi zatorami podróżni przesiadają się na rowery lub nawołują do odbudowania sprawnej komunikacji miejskiej.
PL
W 2000 roku w WPH S.A. jej akcjonariusz strategiczny, francuska Spółka Valfound zrealizowała inwestycję polegającą na uruchomieniu instalacji do wielkoseryjnego wytwarzaniu odlewów korpusów zacisków hamulcowych, przeznaczonych dla producentów samochodów Volkswagen i Peugeot. Inwestycja polegała na zorganizowaniu, dostarczeniu i uruchomieniu grawitacyjnej kokilowej odlewni, w której proces odlewania odbywa się na kokilarce karuzelowej, natomiast obróbka skrawaniem odlewów odbywa się na dwóch liniach wyposażonych w obrabiarki sterowane numerycznie, produkcji niemieckiej.
EN
In 2000 the French company Valfound, a strategic shareholder of Hydraulic Pumps Factory (WPH S.A.), realised an investment project to set in motion a facility for large-lot manufacture of cast bodies of brake calipers for the manufacturers of Volkswagen and Peugeot cars. Within the investment, a gravity chill casting plant was arranged, delivered and put into operation, where the casting process is performed on a carousal permanent mould casting machine, and the castings are machined in two lines equipped with German-made, numerically controlled machine tools.
EN
The notion of Cr,s and C∞,s-diffeomorphisms is introduced. It is shown that the identity component of the group of leaf preserving C∞,s-diffeomorphisms with compact supports is perfect. This result is a modification of the Mather and Epstein perfectness theorem.
EN
The article presents the results of research on the history of Polish-Ukrainian relations in archeology up to the first years of the Second World War. The author concentrated on the part of western Ukraine which until 1940 was connected politically or culturally with Poland (the lands of the former Kingdom of Poland and the Second Polish Republic - 1918-1939). Polish-Ukrainian relations are presented against the background of the political history of the region. In the history of Polish and Ukrainian archaeology Lwów/Lviv (German Lemberg) is among the most important centres of scholarship and research. The article describes Polish archaeologists from the end of the 18th century to the 1940s and their activities in Western Ukraine. Some Ukrainian researchers and institutions are also mentioned.
6
Content available remote Commutators of diffeomorphisms of a manifold with corners
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EN
It is shown that the identity component of the group of al compac tly suported C infinity -diffeomorphisms of a manifold with corners is perfect provided the manifold has no vertices. An analogous result for Cr -diffeomorphism still holds whenever r > n+1, wheren is the dimension of the manifold. These results constiute a generalization of a well-known theorem by Thurston and Mather on the simplicity of diffeomorphism groups of boundaryless manifolds.
8
Content available remote Kolejowa sieć trakcyjna powrotna a kwestia zagrożeń porażeniem elektrycznym
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PL
W artykule przedstawiono zagadnienia związane z ochroną przeciwporażeniową człowieka w kolejowych trakcyjnych sieciach powrotnych. Scharakteryzowano skutki oddziaływania prądu stałego na organizm ludzki, omówiono obowiązujące normy i przepisy prawne dotyczące zagrożeń elektrycznych oraz przedstawiono konstrukcję sieci powrotnej. Wskazano także szczególnie niebezpieczne przypadki awarii sieci powrotnej i ich wpływ na kształtowanie się napięć szyna–ziemia pod wpływem obciążenia sieci przez prądy robocze pojazdów trakcyjnych.
EN
Problems related to electrical shock safety on railway traction return circuits are presented in the article. The results of influence of direct current on human body are described, the valid standards and law regulations related to electrical hazards are discussed and a structure of return circuit is presented. Authors denoted particularly dangerous examples of breakdowns of return circuits and their influence on generated voltages rail-earth in the condition of traction system loaded by operating currents of traction vehicles.
PL
W Polsce koleje, w porównaniu z transportem samochodowym pod względem liczby wypadków śmiertelnych można uważać za wyraźnie bardziej bezpieczny środek przewozu pasażerów. Ponieważ życie i zdrowie ludzkie są wartościami bezcennymi, należy stale mieć na uwadze zagadnienia zawiązane z bezpieczną eksploatacją tego środka transportu, pomimo zadowalających w tym zakresie statystyk.
EN
It is shown that in some generic cases the identity component of the group of leaf preserving diffeomorphisms (with not necessarily compact support) on a foliated open manifold is perfect. Next, it is proved that it is also bounded, i.e. bounded with respect to any bi-invariant metric. It follows that the group is uniformly perfect as well.
11
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EN
Given a principal G-bundle [formula] let HG(M) be the identity component of the group of G-equivariant homeomorphisms on M. The problem of the uniform perfectness and boundedness of HG(M) is studied. It occurs that these properties depend on the structure of H(B), the identity component of the group of homeomorphisms of B, and of B itself. Most of the obtained results still hold in the [formula] category.
12
Content available Mechanized lentil collection in Slovak
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EN
This paper presents the results of the study on seed losses in lentil occuring in mechanized multiphase graded collection. The harvest consist of four operations which caused different losses of lentil’s seeds. The minimal seed’s damage was obtained during threshing with a moisture content of 14.5 %.
PL
W pracy przedstawiono wyniki badań dotyczące strat nasion przy mechanicznym zbiorze soczewicy. Zbiór wykonywano czteroetapowo: koszenie (kosiarka Busahis), zgrabianie (zgrabiarka Lockwood 850), zbiór z rzędów (kombajn E-512 z podbieraczem), omłot (kombajn E-512). Straty nasion w poszczególnych etapach zbioru były zróżnicowane i wynosiły: koszenie - 4.7 %, zgrabianie 1.2 %, zbioru - 6.8 %, omłotu - 1.54 %. Minimalne uszkodzenia mechaniczne (1.6 %) uzyskano przy omłocie soczewicy o wilgotności nasion 14.5 %.
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