New trends in rock mass characterisation for designing geotechnical structuresDrago Ocepek
, 2005, izvirni znanstveni članek
Opis: The investigation on designing supporting measures for geotechnical structures consists of the proper selection of the input data for the stress – strain analysis of the excavation process and the selection of retaining measures. In the preliminary phase of investigation the area must be geologically mapped in detail, and discontinuities precisely measured, boreholes and their “in situ” tests listed and samples for laboratory examinations taken. The new method allows rock mass classification for different rock quality, from soft rocks to mixed rock masses, as well as determination of the geological strength index GSI. The limits for using the suggested method are persistent discontinuities in rock mass which lead to translation or rotation failure mechanisms, either in a single plane or as a wedge. In all cases where discontinuities play a significant role, the rock mass structure must be considered and kinematical analyses performed. In other circumstances, a rock may be uniform and reasonably isotropic due to the geometry of discontinuities and their mutual intersections. The value range of GSI is first determined in the beginning of investigation and later in the excavation phase by considering the disturbance factor D, which expresses disturbances caused by excavation methods and rock mass relaxation. The strength and deformability parameters of rocks of different quality are determined by the generalized Hoek-Brown failure criterion and applied to shallow and deep tunnels or slopes. Before the start of excavations work and after establishing the retaining measures, the analysis results are checked by monitoring. New methods include the determination of post peak strength parameters of rock mass after relaxation, and routine measurements. The newest measurement system however allows direct readings of displacements of the rock mass in both the elastic and post-peak states. With back analyses we determine the softening behavior of the rock mass and a possible need for increasing retaining measures. Such a design method enables the optimization of retaining measures and the reduction of investment costs.
Ključne besede: geological strength index – GSI, simulation of a triaxial large scale »in situ« test, numerical modeling, retaining measures, rock reinforcement, monitoring, back analyses, strain softening, rock mass relaxation
Objavljeno v DKUM: 16.05.2018; Ogledov: 730; Prenosov: 36
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Suitability of heat treatment for crack resistance of material in the connection part of heavy transporter for liquid slagTomaž Vuherer
, Ljubica Milović
, Milorad Zrilić
, Ivan Samardžić
, Vladimir Gliha
, 2013, kratki znanstveni prispevek
Opis: The post weld heat treatment (PWHT) was used to reduce the level of the residual stresses and increase of the crack resistance of the materal in the cnnection part. The article presents the results of the residual stress measurements immediately after welding and after the stress relaxation by the PWHT.
Ključne besede: weld, heat treatment, residual stress, stress relaxation, crack resistance
Objavljeno v DKUM: 03.07.2017; Ogledov: 1762; Prenosov: 71
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The role of background music in the English language classroomAnna Sorger
, 2013, diplomsko delo
Opis: According to the Statistical Office of the Republic of Slovenia, the interest in second language learning has been increasing in recent years. In the context of primary and secondary education in Slovenia, English language is prominent in the field of foreign languages. A quite similar picture can also be seen in the context of non-formal educational system for adults (http://www.stat.si).
Throughout recent years, more and more attention has been given to the importance of a learning environment. Stimulating and pleasant learning environment has a considerable impact on the actors of an educational process and the results of a learning process. Many researchers and educators have been trying to discover the path to effective teaching and learning. In the 1970s, Dr. Georgi Lozanov, the Bulgarian psychotherapist, developed a teaching method called Suggestopedia. The approach was based on the idea that positive suggestion stimulates the learning process. Relaxation techniques, music and a pleasant environment are central to this approach. Mainly it was used to teach foreign languages.
The purpose of this graduation thesis is to determine the impact of background music in the English language classroom. Additionally, it is examined whether the age factor plays a role in the perception acceptance to listening to music in the English classroom. It is assumed that learners have a positive experience regarding the use of background music in the English language classroom. By using a questionnaire we found out that learners (both, younger and older) are more relaxed during English lessons when background music is being played. Learners also tend to listen to it more often during English lessons. It was also found out that, compared to younger learners, adult learners use various relaxation techniques in order to increase relaxation during studying more often.
Ključne besede: English language classroom, background music, learning environment, relaxation
Objavljeno v DKUM: 08.01.2014; Ogledov: 1430; Prenosov: 128
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On the problem of formulating principles in nonequilibrium thermodynamicsPaško Županović
, Domagoj Kuić
, Davor Juretić
, Andrej Dobovišek
, 2010, izvirni znanstveni članek
Opis: In this work, we consider the choice of a system suitable for the formulation of principles in nonequilibrium thermodynamics. It is argued that an isolated system is a much better candidate than a system in contact with a bath. In other words, relaxation processes rather than stationary processes are more appropriate for the formulation of principles in nonequilibrium thermodynamics. Arguing that slow varying relaxation can be described with quasi-stationary process, it is shown for two special cases, linear nonequilibrium thermodynamics and linearized Boltzmann equation, that solutions of these problems are in accordance with the maximum entropy production principle.
Ključne besede: thermodynamics, entropy, relaxation, stationary process, entropy production
Objavljeno v DKUM: 07.06.2012; Ogledov: 1114; Prenosov: 342
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