Zagadnieniem dotąd nierozwiązanym w kopalniach rud miedzi LGOM jest określanie pionowej lokalizacji ognisk wstrząsów. Podejmowane próby w tym względzie, bazujące na parametrach czasowych i amplitudowych rejestrowanych zjawisk sejsmicznych nie przyniosły dotychczas zadawalających rezultatów. Dająca pozytywne wyniki lokalizacji metoda, oparta na rejestracji układem stanowisk zlokalizowanych na różnej głębokościach w szybach kopalnianych posiada natomiast ograniczony zasięg odległościowy. Zaproponowane przez autorów nowe podejście do wyznaczania pionowej lokalizacji ognisk wstrząsów polega na wykorzystaniu do tego celu, ich parametrów energetycznych określanych z rejestracji dołową siecią stanowisk sejsmicznych oraz siecią stanowisk powierzchniowych przeznaczonych do oceny oddziaływań sejsmicznych na obiekty powierzchniowe. Niepodważalną przesłanką dla przyjętego rozwiązania jest istnienie obiektywnych relacji pomiędzy umowną energią sejsmiczną określaną na poziomie złoża, względem umownej energii sejsmicznej wyznaczonej dla stanowisk powierzchniowych. Stosunek tych energii musi bowiem zależeć od wielkości tłumienia fali sejsmicznej na drodze przejścia od źródła wstrząsu do stanowisk pomiarowych, a tym samym od głębokości położenia ogniska wstrząsu. Przeprowadzona analiza na zbiorze danych pomiarowych potwierdziła poprawność przyjętego rozwiązania, którego końcową postać stanowi opracowany wskaźnik głębokości położenia ognisk wstrząsów. Uzyskane wyniki lokalizacji głębokościowej są zbieżne z pionową lokalizacją ognisk wstrząsów wyznaczoną na podstawie stanowisk sejsmicznych w szybach kopalnianych.
Maritime law is being faced with developments in design and production of autonomous vessels. With the rise of new technologies different risks emerge while traditional cease to exist. This paper suggests possible scenarios in relation to development of law relating to unmanned vessels. Second part of the paper is dedicated to analysis of the IMO civil liability convention and its application to autonomous ships on the example of the CLC.
The paper presents an analysis of energy and economic effectiveness of the combined heat and power (cogeneration) technologies fired with natural gas that may be deemed prospective for the Polish electric power system. The current state of the cogeneration technologies fired with natural gas in Poland is presented. Five cogeneration technologies fired with natural gas, prospective from the point of view of the Polish electric power system, were selected for the analysis. Namely, the paper discusses: gas-steam combined heat and power (CHP) unit with 3-pressure heat recovery generator (HRSG) and steam interstage reheat, gas-steam CHP unit with 2-pressure HRSG, gas-steam CHP unit with 1-pressure HRSG, gas CHP unit with small scale gas turbine, operating in a simple cycle and gas CHP unit with gas engine. The following quantities characterizing the energy effectiveness of the cogeneration technologies were selected for the analysis: electricity generation efficiency, heat generation efficiency, primary energy savings (PES) and CO2 unit emission. The economic effectiveness of particular technologies was determined based on unit electricity generation costs, discounted for 2019, including the costs of purchasing CO2 emission allowances. The results of calculations and analyses are presented in a table and on a figures.
Knowledge of uterine fibroids has existed since the time of Hippocrates. However, there are still wide gaps in the understanding of its pathogenesis. No single theory explains the background of uterine fibroid pathology, which affects more than 50% of women worldwide. By contrast, a newly depicted cell type called telocytes was only recently identified in the past twenty years. Th ese cells have evoked ambivalent opinions in the scientific community. The unique features of telocytes coupled with experimental evidence by numerous researchers and our hypotheses and conceptions are discussed in this review. We emphasize the main telocyte interactions in the context of the uterine fibroid architecture. This review reveals the pivotal role of telocytes, describing their contacts with smooth muscle cells, fibroblasts, vessels and nerves, inflammatory cells and stem cells. Our data are based on the latest publications and our own results.
Tonnacypris glacialis (G.O. Sars, 1890) is a meiobenthic species widely distributed in Arctic freshwater lakes. Field study of its life cycle as well as the laboratory experiments showed clearly that only one generation of this ostracod species occurs during the vegetation season, and that the condition necessary for the next generation to appear is eggs freezing.
Genetic variability of two populations of Arctic freshwater crustacean Lepidurus arcticus (Crustacea, Notostraca) occuring in small tundra reservoirs near the Polish Polar Sta− tion in Hornsund (Spitsbergen) was studied. The allozyme polimorphism analysis of 11 en− zyme systems indicates a considerable distinctness and genetically heterogeneous character of the populations of L. arcticus inhabiting freshwater reservoirs of similar hydrological con− ditions situated close to each other (2 km). Our research revealed a complicated and geneti− cally heterogeneous character of the populations. Three hypotheses about genetic structure and type of reproduction were tested: hypothesis M – the free transfer without assigning a clone for particular reservoir and the lack of doublemutations; hypothesis I – separation of in− dividuals between reservoirs and the possibility of doublemutations; hypothesis S – presence of partial sexual reproduction in the population, probably with males. In conclusion participa− tion ofmales in reproduction is probable, despite their presence was not recorded in our study. Males usually occur in low numbers or not every year. The populations' clonal structure as well as the genetic diversity typical of species reproducing sexually was observed. The Hardy−Weinberg genetic equilibrium is maintained as new clonal lines appear due to the ge− netic diversity increasing incidentally as a result of sexual reproduction.
The selection of the most proper strengthening method/system with an assessment of its effectiveness is quite complicated in the case of masonry structures, mainly due to their huge diversity in materials. The most popular strengthening materials based on the composite fibres and are laid on the masonry wall using epoxy adhesives (FRP system) or mineral mortars (FRCM system). This article presents a comparison of external strengthening made using different glass-fibre-based materials on the behaviour of specific masonry walls. The walls are made of AAC blocks (Autoclaved Aerated Concrete), commonly used in rather low urban buildings or skeleton construction. As a strengthening material the GFRP sheets and two types of glass meshes are used. The walls are subjected to diagonal compression, which reflects the shearing of the walls. The scope of research describes cracking stage, shear capacity and analysis of the mode of failure of tested walls.