28 research outputs found

    Structure Constant of the Yang-Lee Edge Singularity

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    This paper studies the Yang-Lee singularity of the 2-dimensional Ising model on the cylinder via transfer matrix and finite-size scaling techniques. These techniques enable a measurement of the 2-point and 3-point correlations and a comparison of a measurement of a corresponding universal amplitude with a prediction for the amplitude from the (A4,A1) minimal conformal field theory.Comment: 1 figur

    Excitation Spectrum at the Yang-Lee Edge Singularity of 2D Ising Model on the Strip

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    At the Yang-Lee edge singularity, finite-size scaling behavior is used to measure the low-lying excitation spectrum of the Ising quantum spin chain for free boundary conditions. The measured spectrum is used to identify the CFT that describes the Yang-Lee edge singularity of the 2D Ising model for free boundary conditions.Comment: 7 pages, 1 figur

    Critical Excitation Spectrum of Quantum Chain With A Local 3-Spin Coupling

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    This article reports a measurement of the low-energy excitation spectrum along the critical line for a quantum spin chain having a local interaction between three Ising spins and longitudinal and transverse magnetic fields. The measured excitation spectrum agrees with that predicted by the (D4_4, A4_4) conformal minimal model under a nontrivial correspondence between translations at the critical line and discrete lattice translations. Under this correspondence, the measurements confirm a prediction that the critical line of this quantum spin chain and the critical point of the 2D 3-state Potts model are in the same universality class.Comment: 7 pages, 2 figure

    Impact of the Winding Angle of the Auger Blade on the Loading Process With Milling Auger Drums

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    This publication addresses the impact of selected design parameters of milling auger cutting drums on the loading process, and above all the winding angle of the auger blade. The loading process is often referred to as an auxiliary process because the milling process is considered to be the dominant throughout the work of the cutting drum. The correct determination of the relationship between the mining process and the loading process allows to understand how the individual design and kinematic parameters of the mining drums and the mining machine on which they are installed affect each other. The publication discusses the problem of loading with milling cutting drums and ways to increase its efficiency. The research results of the loading process have been presented, affecting the efficiency of this process in the aspect of various angles of inclination of the auger blades. Based on the tests, conclusions have been formulated that allow for the possible selection of an appropriate winding angle for the auger blade, depending on the granulation of spoil

    Impact of selected parameters on the loading process with cutting screw heads

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    The article presents the influence of selected constructional and kinematic parameters of cutting screw heads on the loading process. The loading process is often referred to as an auxiliary process, because in the entire operation of the head the cutting process is considered dominant. Proper determination of the relationship between the cutting process and the loading process allows to understand how individual constructional and kinematic parameters of cutting heads and the cutting machine on which they are installed have an impact on each other. This knowledge gives potential users an opportunity to determine a reason for the lack of effective loading in the working conditions of a given wall. Besides construction and kinematic parameters, shielded loaders also have an impact on the loading process. The use of a shielded loader allows for improving the efficiency of the loading process, i.e. increasing the percentage of output loaded in the whole of the output transferred by the head

    Małopolskie górnictwo skał magmowych – technologia wydobycia na przykładzie Kopalni Porfiru „Zalas”

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    The geological structure and rock resources of the region of Krakow are very diverse. This results from its location at the junction of three structural units as well as from the variety of geological processes that have taken place during their geological history. Devonian to Quaternary formations are visible on the surface, while the rocks found in boreholes are even older. Igneous rocks in the region of Małopolska (Lesser Poland) are concentrated in a relatively small area. The following rocks have been mined in the past: red porphyry in Miękinia, melaphyre in Regulice, porphyry in Orla. Currently active mines – quarries, which are engaged in continuous exploitation, include the “Zalas” Porphyry Mine in Zalas and the “Niedźwiedzia Góra” Diabase Mine in Tenczynek.Budowa geologiczna oraz zasoby skalne okolic Krakowa są bardzo urozmaicone. Wynika to z jednej strony z położenia tego obszaru na styku trzech jednostek strukturalnych, a z drugiej strony jest spowodowane różnorodnością zachodzących w tej części Małopolski procesów geologicznych. Na powierzchni terenu ukazują się utwory powstałe w okresie od dewonu do czwartorzędu, natomiast w otworach wiertniczych stwierdzono skały jeszcze starsze. Występowanie skał magmowych w Małopolsce koncentruje się na stosunkowo małym obszarze. W przeszłości eksploatowano czerwony porfir w Miękini, melafir w Regulicach oraz porfir w miejscowości Orlej. Obecnie czynne kamieniołomy, prowadzące ciągłą eksploatację to Kopalnia Porfiru „Zalas” w miejscowości Zalas oraz Kopalnia Diabazu „Niedźwiedzia Góra” w Tenczynku
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