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Abstract

W pracy przedstawiono wybrane analizy oceny odporności dynamicznej zabudowy mieszkalnej i gospodarczej na wpływy eksploatacji górniczej w obszarze górniczym jednej z kopalń węgla kamiennego. Rozważania ograniczono do dynamicznych efektów związanych z powstawaniem wstrząsów górniczych generowanych podziemną eksploatacją surowca. W ramach pracy wykonano analizę sejsmiczności analizowanego obszaru z uwagi na wpływ rejestrowanych i prognozowanych drgań powierzchniowych na tradycyjną niską zabudowę murowaną. Wykonano modele symulacyjne zbudowane zgodnie z Metodą Elementów Skończonych oraz dobrano kryteria odporności dynamicznej. Kryteria odporności dynamicznej przyjęto zgodnie z obowiązującymi normami i zasadami projektowania budynków murowanych. Obliczenia przeprowadzono z wykorzystaniem metody spektrum odpowiedzi, która jest normową metodą projektowania obiektów poddanych wpływom wstrząsów górniczych. Takie podejście jest również zalecane przez większość polskich instrukcji i wytycznych dotyczących projektowania budynków w rejonach o sejsmiczności indukowanej działalnością wydobywczą. Efektem analiz było określenie wytężenia podstawowych elementów konstrukcyjnych w przyjętych modelach obliczeniowych. Wyniki analiz skoncentrowanych na wpływie wstrząsów górniczych na zabudowę powierzchniową i sieć infrastruktury technicznej oraz ich zabezpieczeniach w obszarze górniczym ZG Janina mogą być przydatne w kontekście możliwości dalszej eksploatacji pokładów węgla w kolejnych latach, z zachowaniem bezpieczeństwa powszechnego, ochrony obiektów budowlanych, w tym zapobiegania szkodom. Przedstawione w pracy wyniki stanowią również uzupełnienie tworzonej przez autorów od kilku lat bazy obiektów i modeli dynamicznych budowli poddanych wpływom wstrząsów górniczych.

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Authors and Affiliations

Filip Pachla
Tadeusz Tatara
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Abstract

The box wing system is an unconventional way to connect the lifting surfaces that the designers willingly to use in prototypes of new aircrafts. The article present a way to quickly optimize the wing structure of box wing airplane that can be useful during conceptual design. At the beginning, there is presented theory and methods used to code optimization program. Structure analysis is based on FEM beam model, which is sufficient in conceptual design. Optimization is performed using hybrid method, connection of simple iteration and gradient descent methods. Finally, the program is validated by case study.

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Authors and Affiliations

Miłosz J. Kalinowski

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Abstract

The Catholic image of Martin Luther in the course of the centuries evolved from the literally negative one during the time of the Reformation and the centuries that followed, through the theological attempts and historically in-depth analyses inspired by the ecumenical movement up to contemporary acceptance of several theological postulates. Contemporary movements of Roman-Catholic thinking of Luther well summarize historically vulnerable and dogmatically deepened opinions of the recent popes: John Paul II, Benedict XVI and Francis. Following the agreement texts of the Lutheran-Catholic Commission at the world forum, ecumenically open popes can find out in Martin Luther a profoundly religious man, the witness of the Gospel whose theological thought is still relevant and a challenge for the presently secularized world.

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Authors and Affiliations

Piotr Jaskóła
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Abstract

The subject of many controversies has been both the understanding of the limits of scientific knowledge and the indication of the “boundary” conditions of orders placed for it. In some cases, we are in favor of widening these boundaries in such a way that they can also include religious and quasi-religious beliefs, while in others we are in favor of narrowing them so that knowledge and faith can be clearly distinguished. In these considerations, I cite examples of positions on both issues that have in the past met with both relatively wide acceptance and serious reservations. It is worth taking a closer look at them, because it turns out that in science nothing is decided once and for all, and what seemed to belong to the past sometimes comes back with even greater force. I show this on two examples of contemporary positions on the issue of understanding the limits of scientific knowledge.
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Authors and Affiliations

Zbigniew Drozdowicz
1
ORCID: ORCID

  1. Instytut Kulturoznawstwa, Uniwersytetim. Adama Mickiewicza
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Abstract

The paper presents the results of the studies on the determination of the degree of dependence between the adjusted observations, on the basis of the levels of their coexistence in a network. An approximate model is proposed making it possible to estimate that dependence without the necessity to perform the adjustment procedure. This model can be applied in the procedures of gross error detection in observations. Additionally, a supplementary algorithm to determine the coexistence levels for the observations on the grounds of the matrix of coefficients in the observation equations is presented.
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Authors and Affiliations

Mieczysław Kwaśniak
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Abstract

The diagnostics of track superstructure, which involves geometric measurements, direct observation and railroad surveillance, provides the basis for making decisions regarding the commencement of repair works. Planning repairs and increasing the probability of making the right decision at the right time also requires knowledge of the basic performance specifications of a given railway line, especially the maximum train speed and the permissible traffic volume. The article discusses a way to plan the repairs of track superstructure using artificial neural networks. It features a description of the process of designing, building and training a neural network, based on which a way to predict the degree of urgency of repairs has been discussed. The conclusions point towards the potential advantages of neurocomputers in the process of track superstructure maintenance.

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Authors and Affiliations

Henryk Bałuch
Iwona Nowosińska
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Abstract

During thirty three expeditions to the Polish Arctowski Antarctic Station signifi− cant influences of human activity upon the environment have been recorded. Introductions of alien species, shifts of bird and seal breeding areas and decreases in both bird and seal populations, are the most obvious effects of human pressure. Though numbers of visits by tourists have increased during this period, impacts from expeditioners appear to be the main cause of changes. In particular, increasing numbers and mobility of summer groups at the station are the likely most influential factors.

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Authors and Affiliations

Katarzyna J. Chwedorzewska
Małgorzata Korczak

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