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tom Vol. 4
57--64
EN
The Czarny Dunajec is a typical river originating in high mountains (the Western Tatras). Over the entire Quaternary era the river laboured carrying material away from the Tatras and depositing it in the form of a typical braided channel at their foot. At the end of the 19'h century, river management projects and quarrying operations located directly in the very channel set off a rejuvenation process that was further accelerated at the end of 1960s. The activities resulted in the damaged several sections in their natural form and considerably deepened the channel. Measures taken to restrict the amount of material entering the Czorsztyn Dam have largely failed. From the geomorphologic and environmental points of view a continued transformation of the Czarny Dunajec river channel should be regarded as highly adverse.
PL
Referat stanowi w głównej mierze przegląd literaturowy, w którym omówiono dotychczasowe zastosowania metody impact-echo w diagnostyce uszkodzeń konstrukcji żelbetowych. Przedstawiono w niej teoretyczne podstawy metody oraz dotychczasowe standardowe jej zastosowania. Praca prezentuje również zrealizowane badania wstępne, które miały na celu weryfikację, czy za pomocą metody impact-echo możliwe jest identyfikowanie skutków poddania betonu działaniu wysokiej temperatury.
EN
The paper is mainly the state-of-the-art which discusses the current use of impact-echo method in the diagnosis of damage to reinforced concrete structures. It also presents the theoretical basis of the method and summarizes its standard applications reported in publications. Additionally, paper presents the results of a preliminary study, aimed at verifying the usefulness of the impact-echo method for diagnosis the effects of high temperature on concrete.
EN
Purpose: The purpose of the paper was to develop a method of methane risk assessment in order to fulfil the technical-organizational and legal requirements for occupational risk assessment in mines. Methane hazard and associated risks of the effects of ignition and/or explosion of methane is one of the most severe natural hazards. Methods: Heuristic methodology based on the Delphi approach and a group survey by a panel of experts, which was named SOPE, was used to assess the magnitude of methane risk. The adopted tools for assessing the current state of methane risk factors and their possible accident consequences were targeted surveys, with the participation of experts representing, mainly, engineering-technical personnel of mine ventilation service. The objectivity and independence of the judgment of the ex-perts was checked by determining indicators of the degree of the experts’ unanimity, indicators of their competence as well as indicators of the validity of their evaluations. The subject matter of the study of methane hazard were five longwall are-as of the "A-Z" twin-mine (after the merge of two mines: Mine A and Mine Z), three longwalls operated towards plant A and two longwalls operated towards plant Z. For the assessment of each area of the mine, a Methane Risk Assessment Questionnaire consisting of 4 assessment cards, was used. The cards included four areas of the studied risk factors, i.e. factors shaping the methane hazard (17 factors), the activity of the methane ignition initiators (19 factors), detection and prevention of methane risk (16 factors) and possible human and material losses (13 factors). Results: The evaluation of 65 factors affecting the causes and consequences of the methane risk in the exploitation area under ana-lysis, was conducted in accordance with the procedure of the adopted method, based on the proposed algorithm. Assess-ments by experts were used to calculate the indicators of the magnitude of methane hazard for each group of factors sepa-rately. Practical implications: A practical example of the application of this method is incorporated in chapter four of this paper, which also discusses the results of the conducted research. Originality/ value: The obtained values of the indicators of methane risk assessment and analysis of their changes showed that the proposed method can be an important element in the design and construction of a modern methane safety system in coal mines. It provides the possibility of controlling this risk and enables the minimization of its consequences in accordance with the criteria of their acceptance, adopted in this paper. The method does not replace the currently used methods of methane risk assessment, but complements them in a significant and modern way.
4
Content available remote Ocieplać z głową
63%
PL
W referacie przedstawiono tematykę zagrożenia metanowego w świetle teorii ryzyka zawodowego, z zastosowaniem metody oceny jakościowej z udziałem ekspertów. Zaprezentowano zidentyfikowane czynniki wysokiego ryzyka zapłonu i wybuchu metanu oraz dokonano ich podziału na grupy znaczeniowe takie jak czynniki litosferyczno-technologiczne CZ, czynniki zainicjowania zapłonu CI, czynniki organizacji, wykrywania i profilaktyki metanowej CO oraz czynniki możliwych skutków ryzyka metanowego CS. W oparciu o przedstawioną procedurę dokonano oceny i klasyfikacji czynników ryzyka metanowego. Na tej podstawie zaproponowano niekonwencjonalne metody redukcji ryzyka metanowego odniesione do czynników ryzyka, których oddziaływanie uznane zostało przez ekspertów za najbardziej niekorzystne.
EN
The paper presents the topic of methane hazard in the light of occupational risk assessment theory, using the qualitative assessment method with the participation of experts. The identified risk factors of ignition and methane explosion were presented and they were divided into semantic groups such as lithospheric and technological factors CZ, ignition factors CI, organization, methane detection and prevention factors CO and possible consequences of methane risk CS. Based on the presented procedure, the methane risk factors were assessed and classified. On this basis, unconventional methane risk reduction methods were proposed related to risk factors, which impact was considered by the experts the most unfavorable.
EN
Studies on the dynamics of geomorphologic processes occurring in the Tatras began in the 1950s and continue to pique the interest of researchers. The history of the study of Tatra relief morphodynamic changes is marked by certain breakthrough stages associated with the emergence of key works yielding multiplier effects. These works identified new directions and sparked new trends in geomorphologic research as well as inspired deeper analysis of the study area. A significant acceleration of geomorphologic research in the Tatras has occurred in the most recent decade. This resulted mostly from the use of complex monitoring of key dynamic geomorphologic processes and the use of lichenometric and dendrogeomorphologic methods, which enable the identification of complete event chronologies. The present study reviews the most important quantitative studies on the evolution and rate of contemporary geomorphologic processes in the Tatras as well as novel research data produced in the last several years. The authors note principal research directions and the discuss relevant works on the identification of contemporary and relict periglacial relief along with papers on the dynamics of slope and fluvial processes and anthropogenic erosion. The paper also describes certain tendencies observed recently in the realm of morphogenetic processes associated with ongoing climate change.
PL
Tematyka artykułu należy do obszaru zarządzania ryzykiem zagrożeń naturalnych. Jest kontynuacją badań autorów nad określeniem wielkości ryzyka metanowego w rejonach eksploatacji ścianowej kopalń węgla w Polsce. W artykule skupiono uwagę na identyfikacji zbioru czynników organizacyjnych wpływających na poziom ryzyka zapalenia i/lub wybuchu metanu. Do oceny wielkości ryzyka metanowego wykorzystane zostały: autorska procedura heurystyczna oparta na technice grupowego sondażu opinii panelu ekspertów SOPE-RM oraz autorska metoda szacowania jakościowego RMQE-IM umożliwiająca transformację rozpoznanych czynników mierzalnych i niemierzalnych ryzyka metanowego do jednolitej jakościowej skali ocen tego ryzyka. Stosowanymi narzędziami oceny aktualnego stanu czynników zagrożenia metanowego oraz ich możliwych skutków wypadkowych były sondaże ankietowe, z udziałem 190 specjalistów-ekspertów reprezentujących w przewadze kadrę inżynieryjno-techniczną służb wentylacji z siedmiu kopalń węgla kamiennego w Polsce.
EN
The subject matter of the article belongs to the area of natural hazards management. It is a continuation of the authors' research on identifying of methane hazard' magnitude in the areas of longwall's coal mining operations in Poland. The article focuses on the identification of a set of organizational factors affecting the level of risk of ignition and / or explosion of methane. In order to assess the methane hazard the following were used: the original authors' heuristic procedure based on the technique of group opinion surveying by the SOPE-RM experts and original authors' method of qualitative estimating RMQE-IM enabling the transformation of the identified factors, measurable and immeasurable factors of methane hazard methane into the single qualitative evaluation scale of this hazard. The surveys, involving 190 specialists-experts representing predominantly ventilation engineering and technical personnel of seven coal mines in Poland, were the appropriate tool for assessing the current state of the methane hazard's factors and the possible consequences of the accident.
PL
W artykule opisano badania kształtowania się stanów ryzyka metanowego z zastosowaniem procedur systemowo-ekspertowej metody oceny jakościowej ryzyka zapłonu i wybuchu metanu (RMQE-IM). Badania przeprowadzono w siedmiu kopalniach węgla kamiennego dla 19 rejonów eksploatacji ścianowej. W ramach badań dokonano identyfikacji i klasyfikacji czynników ryzyka metanowego, usystematyzowanych w cztery grupy. Badania w kopalniach przeprowadzono metodą sondażowo-ekspertową, uczestniczyło 190 ekspertów.
EN
The article describes the research on development of the states of the methane risks using the procedures of the system-expert methods of qualitative assessment of methane ignition and explosion risk (RMQE-IM). The study was conducted in seven hard coal mines for 19 areas of long-wall mining operations. The identification and classification of methane risk factors were performed during the study, structured into four groups. Research in the mines was performed by survey-expert method, attended by 190 experts.
11
Content available remote Wpływ działalności człowieka na funkcjonowanie górskich systemów fluwialnych
51%
PL
W artykule przedstawiono współczesny stan wiedzy o przyczynach zmian karpackich koryt oraz ich reakcji na różne interwencje. Zaprezentowano też kilka nowoczesnych, alternatywnych rozwiązań w kwestii zarządzania górskimi systemami fluwialnymi.
EN
The article demonstrates the present state of knowledge about the reasons of Carpathian channel changes and channel response to various interferences. A range of modern alternative solutions in the matter of mountain fluvial system management is also presented.
PL
Artykuł pokazuje wpływ wybranych systemów regulacyjnych na negatywne zmiany w korytach rzek karpackich. Jako przykładowe wybrano koryta: Białego Dunajca i potoku Mszanka. Dodatkowo zwrócono uwagę na problem nielegalnego poboru rumowiska z koryt rzecznych i jego wpływu na degradację koryt.
EN
The article demonstrates the influence of chosen regulation systems on negative changes in beds of the Carpathian rivers. As examples were chosen: Biały Dunajec river and Mszanka stream. Additionally, the authors indicate the problem of illegal river rock debris collection and its influence on the degradation of riverbeds.
PL
W artykule przedstawiono wyniki badań diagnostycznych elementu betonowego poddanego działaniu pożaru. Przeprowadzono ocenę przydatności wybranych metod, głównie nieniszczących, lecz także niszczących, stosowanych do oceny stanu betonu poddanego działaniu wysokiej temperatury. Celem badań było również ustalenie zależności między wybranymi parametrami diagnostycznymi (prędkość rozchodzenia się dźwięku w materiale, liczba odbicia) i resztkowymi właściwościami mechanicznymi uszkodzonego betonu. Stwierdzono dużą zgodność prędkości rozchodzenia się ultradźwięków przy skrośnym ich przepływie, z wytrzymałością próbek na ściskanie, ponadto metoda ultradźwiękowa pozwoliła na ocenę zwartości warstwy betonu uszkodzonego.
EN
The article presents the results of diagnostic tests of the concrete elements, subjected to fire. The assessment of selected methods suitability, mainly non-destructive, but also some destructive, used to determine the properties of the concrete subjected to high temperature, was verified. The aim of the study was to determine the relationship between selected diagnostic parameters (ultrasonic pulse veIocity, rebound number) and the residual mechanical properties of the damaged concrete. It was found that ultrasonic pulse velocity in direct transmission is compliant with specimen compressive strength, moreover, this method allowed to determine the thickness of the damaged concrete layer.
EN
The paper reports on a study of the impact of morphology and lithology of small catchments on episodic river channel development in the southern High Atlas Mountains in Morocco. A detailed analysis focused on three catchments of small wadis featuring different relief and lithology along the upper, middle and lower course of the Dades River. The fieldwork combined with an analysis of topographic and geological maps and of satellite images concluded that the development of the river valley and channel structures was related to the main stages in the development of the landform in this part of the High Atlas. The channel dynamics were found to be typical of arid mountains, which was particularly apparent within a denudational-and-fluvial zone that reached up to 3,000 m a.s.l. The dominant morphodynamic system of this zone was pluvio-gravitational where episodic heavy rainfall events triggered fast displacement of stone mantle covers down the slopes and into the river channels. An analysis of the deposition zones in the lower channel reaches and on alluvial fans at the confluence of the side valleys and the main valley leads to the conclusion that the main factor, which determines the channel morphology is the impact of debris flows and heavily loaded streams and rivers. The deposited material is then transported outside the mountain zone and deposited within broad river channels. The development of the river channels in the three catchments depends on their order, morphometric property, slope lithology and the amount of material received from the slopes.
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