Browsing by Subject "spectral analysis"

Now showing 1 - 8 of 8

Access status: Open Access ,
Analiza efektywności modelowania cyfrowego drgań budynku wywołanych wstrząsami górniczymi
(Wydawnictwa AGH, 2009) Walaszczyk, Jan; Hachaj, Stanisław; Barnat, Andrzej
Dynamic occurrences caused by mining exploitation (e.g. the loss of rock mass stability) result in vibrations of both the rock mass and the building situated on its surface. There are many projects concentrating on measuring or predicting quakes mentioned above and vibrations caused by them. One of the ways of predicting vibrations is digital modeling (e.g. using the Finite Element Method). This type of modeling is restricted in many ways. The most important restrictions include difficulties in identifying digital model of rock mass and buildings, which makes the quality of test results in digital modeling still inefficient. In this paper, the quality of digital modeling is based on the comparison of building vibrations (modeled with FEM) with vibrations recorded with suitable geophysical devices. The basis of the comparison of modeled and measured vibrations is their spectral analysis.
Access status: Open Access ,
Analiza spektralna
(s.n., 1869) Libelt, Karol Fryderyk
Access status: Open Access ,
Analiza spektralna drgań budynku wywołanych wstrząsami górniczymi
(Wydawnictwa AGH, 2009) Walaszczyk, Jan; Hachaj, Stanisław; Barnat, Andrzej
Building vibrations are registered by the measurements of velocity and acceleration. There is question of the quality of these measurements as far as, for example, calculating one of those variables based on the other one is concerned. The answer to this question was searched for by means of spectral analysis of velocity and acceleration measured velocit.
Access status: Open Access ,
Analiza spektralna stóp zwrotu dla spółek z indeksu SMI
(2010) Gurgul, Henryk; Kłęk, Krzysztof
Celem artykułu jest zastosowanie analizy spektralnej do zbadania struktury i częstotliwości szeregów czasowych stóp zwrotu 19 spółek notowanych w indeksie SMI, będącym głównym indeksem giełdy szwajcarskiej. Zbadano też za pomocą metod spektralnych, czy istnieje zależność pomiędzy stopami zwrotu wybranych pięciu spółek reprezentujących pięć głównych branż gospodarki szwajcarskiej. Uzyskane wyniki świadczą o braku istnienia takiej zależności. Nie stwierdzono w szczególności istotnej zależności pomiędzy składowymi częstotliwościami par szeregów czasowych.
Access status: Open Access ,
Łatwo dostępny spektroskop o dużej rozdzielczości z dedykowaną aplikacją mobilną pozwalającą na analizę otrzymanego spektrum
(Wydawnictwa AGH, 2024) Ruba, Łukasz; Błażej, Ryszard; Hulek, Jakub; Kokoszka, Roman; Janik-Kokoszka, Joanna
The article presents the design and implementation of a high-resolution paper spectroscope intended for educational purposes, along with a mobile application that conducts spectral analysis of the image and classifies the spectrum into elements from a built-in database of emission spectra. The image analysis algorithm was created to not require prior calibration, the result is based solely on the received image and the value of the diffraction grating used in the construction of the spectroscope. Experiments were conducted to examine the performance of the spectroscope using light bulbs and Plücker tubes. The accuracy of the image analysis and classification algorithm was tested based on generated images of the emission spectra of elements.
Access status: Open Access ,
Nontrivial solutions of linear functional equations: methods and examples
(2015) Varga, Adrienn; Vincze, Csaba
For a wide class of linear functional equations the solutions are generalized polynomials. The existence of non-trivial monomial terms of the solution strongly depends on the algebraic properties of some related families of parameters. As a continuation of the previous work [A. Varga, Cs. Vincze, G. Kiss, Algebraic methods for the solution of linear functional equations, Acta Math. Hungar.] we are going to present constructive algebraic methods of the solution in some special cases. Explicit examples will be also given.
Access status: Open Access ,
The d-bar formalism for the modified Veselov-Novikov equation on the half-plane
(Wydawnictwa AGH, 2022) Hwang, Guenbo; Moon, Byungsoo
We study the modified Veselov-Novikov equation (mVN) posed on the half-plane via the Fokas method, considered as an extension of the inverse scattering transform for boundary value problems. The mVN equation is one of the most natural $(2+1)$-dimensional generalization of the $(1+1)$-dimensional modified Korteweg-de Vries equation in the sense as to how the Novikov-Veselov equation is related to the Korteweg-de Vries equation. In this paper, by means of the Fokas method, we present the so-called global relation for the mVN equation, which is an algebraic equation coupled with the spectral functions, and the $d$-bar formalism, also known as Pompieu's formula. In addition, we characterize the $d$-bar derivatives and the relevant jumps across certain domains of the complex plane in terms of the spectral functions.
Access status: Restricted ,
Zadanie odwrotne w geofizyce otworowej – rozwiązania dla pojedynczych profilowań geofizyki otworowej i dla kompleksowej interpretacji
(Data obrony: 2010-10-04) Wilk, Monika
Wydział Geologii, Geofizyki i Ochrony Środowiska
The topic of the M.Sc. Thesis was inverse problem in well logging. Several methods of solving it were presented. There were shown some examples of interpretation made for single log as well as for the set of logs. Conventional methods were based on solving single equation and using the program ULTRA for comprehensive interpretation. Paralelly, the author shows efforts to make the interpretation using alternative methods. In case of single log spectra analysis and deconvolution of registered signals were considered. For comprehensive interpretation an expert system was used. All the results were compared with the interpretation from ULTRA program.