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Number of results: 18
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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 aim of the work is to develop and test an algorithm of adjustment of geodetic observations, resistant to gross errors (method of robust estimations), with the use of the damping function, proposed by the author. Detailed formulae of the damping function as a component of the objective function in a modified classic least squares method were derived. The selection criteria for the controlling parameters of the damping functions have also been provided. The effectiveness of the algorithm has been verified with two numerical examples. The results have been analysed with reference to the methods of resistant compensation, which apply other damping functions, e.g. Hampel's function.
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Authors and Affiliations

Tadeusz Gargula
ORCID: ORCID
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Abstract

The aim of this study was to design and test an adjustable hydro-pneumatic damper for cab suspension. The goal was to make a simple and cheap solution for a damper, which is intended to be placed between the hydraulic cylinder and accumulator. Damping behaviour of different terrain types had to be taken into consideration. Terrain type varies from field to road driving and damping should react rapidly to varying conditions.

In this study, the semi-active damper has been built with a hydraulic direct acting cartridge type 2/2-way proportional flow control valve. Flow-pressure curves and dynamic tests were carried out in the laboratory. The dynamic test with forced vibration focused on stability in damping frequencies and step response between different states. Also, total damping force was measured in different damping states and the proportional valve’s precise step responses and stability were investigated in a closed hydraulic system.

As a result, this research gave a lot of new information about the proportional valve’s applicability to work as a semi-active damper and information about damping behaviour. Research showed that a proportional valve can work in a cab suspension damper as well as a multi-fixed orifice damper. Bi-directional flow in the proportional valve was found to remain stable in cab suspension working conditions. The proportional valve also has the ability to work as a continuous state damper, which could lead to better damping results with the appropriate control system.

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Authors and Affiliations

Pasi Ruotsalainen
Kalervo Nevala
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Abstract

The objective of this paper is to derive the characteristics of an effective governance framework ensuring incentives for conducting a prudent fiscal policy.We study this problem with the use of econometric tools and a sample of 28 European Union Member States between 2003 and 2017. By looking at specific reforms and measures, not only we verify the synthetic effectiveness of fiscal constraints but also we analyse specific elements of the governance framework.Our study shows that fiscal balances are affected not only by the economic cycle, but, among others, by the level of public debt and its cost. We find that the existence of numerical fiscal rules, in that specifically revenue and expenditures rules, their strong legal entrenchment, surveillance mechanisms, sanctions, and flexibility with respect to business cycle have a significant impact on curbing deficits.

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Authors and Affiliations

Grzegorz Poniatowski
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Abstract

The present paper consists of two parts. The first part presents theoretical foundations of Msplit, estimation with reference to the previous author's paper (Wiśniewski, 2009). This time, some probabilistic assumptions are described in detail. A new quantity called f-information is also introduced to formulate the split potential in more general way. The main aim of this part of the paper is to generalize the target function of Msplit estimation that is the basis for a new formulation of the optimization problem. Such problem itself as well as its solution are presented in this part of the paper. The second part of the paper presents some special case of Mspli, estimation called squared Mspli, estimation (also with reference to the mentioned above paper of the author). That part presents a new solution and development in the theory of this version of M,plit estimation and some numerical examples that show properties of the method and its application scope.
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Authors and Affiliations

Zbigniew Wiśniewski
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Abstract

The paper presents the results of research on the DiSTFA method (Displacements and Strains using Transformation and Free Adjustment) for the determination of displacement and strains of a surface determined in unstable reference systems. Additionally, covariance matrices were introduced to assess the accuracy of estimation results. The theoretical discussion includes an example of its application in a simulated, three-dimensional geodetic network. The obtained results encourage further, more detailed analysis of real geodetic networks.
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Authors and Affiliations

Waldemar Kamiński
ORCID: ORCID
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Abstract

This part of the paper presents particular case of Msplit estimation called a squared Msplit estimation whose target function is based on convex squared functions. One can find here theoretical foundations and algorithm of the squared Msplit estimation as well as some numerical examples.
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Authors and Affiliations

Zbigniew Wiśniewski
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Abstract

In the research it has been assumed that an observation corresponds to a measured height difference of a levelling section while a pseudo-observation corresponds to a sum of observations for consecutive levelling sections which make up a levelling line. Relations between observations and pseudo-observations are shown. It has also been assumed that observations are not correlated. The study compares Helmert - Pranis-Praniewicz. algorithm of parametric. multi-group (parallel) least squares adjustment of observations with the algorithm of rwo-stage least squares adjustment of levelling network. The two-stage adjustment consists of least squares adjustment of pseudo-observations and then the adjustment of observations, which is carried out separately for each levelling line. It was shown that normal equations concerning heights of nodal points, created on the basis of pseudo-observations, are identical to the reduced normal equations formed on the basis of observations in multi-group adjustment. So, adjusted heights of nodal points and their variance-covariance matrix are the same in the case of adjustment of observations and in the case of adjustment of pseudo-observations. Following a brief presentation of known algorithm of height computation for intermediate benchmarks of levelling lines there is shown the proof that the value of a square root of the a posteriori variance of unit weight 1110, known also as mean square error of a typical observation/pseudo-observation, is the same in the case of adjustment of observations and in the case of adjustment of pseudo-observations. The conclusion states that the results of two-stage adjustment and rigorous least squares adjustment of observations are identical.
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Authors and Affiliations

Idzi Gajderowicz
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Abstract

Slope deformations, i.e., all types of landslides of rock masses (flow, creep, fall down, etc.), caused by gravitational forces, are the most widespread implementation of geological hazards and a negative geomorphological phenomenon that threatens the security of the population, destroy all utility values of the affected regions, negatively affects the environment, and cause considerable economic damage. Nowadays, the Global Navigation Satellite Systems (GNSS) provide accurate data for precise observations around the world due to the growing number of satellites from multiple operators, as well as more powerful and advanced technologies and the implementation of mathematical and physical models more accurately describing systematic errors that degrade GNSS observations such as ionospheric, tropospheric, and relativistic effects or multipath. The correct combination of measurement methods provides even more precise, i.e., better measurement results or estimates of unknown parameters. The combination of measurement procedures and their significant evaluations represent the essential attribute of deformation monitoring of landslides concerning the protection of the environment and the population’s safety in the interest areas for the sustainable development of human society. This article presents the establishment and use of a local geodetic network in particular local space for various needs. Depending upon the specific conditions, it is possible to use GNSS technology to obtain accurate observations and achieve the results applicable to the deformation survey for subsequent processing of the adjustment procedure.
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Authors and Affiliations

Gabriel Weiss
1
ORCID: ORCID
Slavomir Labant
1
ORCID: ORCID
Juraj Gasinec
1
ORCID: ORCID
Hana Stankova
2
ORCID: ORCID
Pavel Cernota
2
ORCID: ORCID
Erik Weiss
3
ORCID: ORCID
Roland Weiss
3
ORCID: ORCID

  1. Technical University of Kosice, Kosice, Slovakia
  2. VSB – Technical University of Ostrava, Ostrava, Czech Republic
  3. University of Economics in Bratislava, Bratislava, Slovakia
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Abstract

The concept of a general average is the oldest institution of maritime law. Its usefulness in modern shipping relations has long been criticized. Nevertheless, the general average, despite the fact that it is not the subject of any international agreement, occupies a prominent place in the internal legal systems of maritime states, and the international community continues to show great interest in it, regularly changing the principles of accounting established in the second half of the 19th century in York and Antwerp. During the work on the draft of the new Polish Maritime Code, the Maritime Law Codification Commission made some changes in the regulations concerning the general average, adapting the provisions of Polish law to new solutions proposed by participants of international maritime trade and non-governmental organizations, including Comité Maritime International.

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Authors and Affiliations

Cezary Łuczywek
ORCID: ORCID
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Abstract

The article introduces a method for selecting the best clamping conditions to obtain vibration reduction during the milling of large-size workpieces. It is based on experimental modal analysis performed for a set of assumed, fixing conditions of a considered workpiece to identify frequency response functions (FRFs) for each tightening torque of the mounting screws. Simulated plots of periodically changing nominal cutting forces are then calculated. Subsequently, by multiplying FRF and spectra of cutting forces, a clamping selection function (CSF) is determined, and, thanks to this function, vibration root mean square (RMS) is calculated resulting in the clamping selection indicator (CSI) that indicates the best clamping of the workpiece. The effectiveness of the method was evidenced by assessing the RMS value of the vibration level observed in the time domain during the real-time face milling process of a large-sized exemplary item. The proposed approach may be useful for seeking the best conditions for fixing the workpiece on the table.
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Authors and Affiliations

Krzysztof J. Kaliński
1
ORCID: ORCID
Marek A. Galewski
1
ORCID: ORCID
Natalia Stawicka-Morawska
1
ORCID: ORCID
Krzysztof Jemielniak
2
ORCID: ORCID
Michał R. Mazur
1
ORCID: ORCID

  1. Gdansk University of Technology, Faculty of Mechanical Engineering and Ship Technology, Institute of Mechanics and Machine Design,Gdansk, 80-233, Poland
  2. Warsaw University of Technology, Faculty of Mechanical and Industrial Engineering, Institute of Manufacturing Processes,Warsaw, 00-661, Poland
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Abstract

Active acoustics offers potential benefits in music halls having acoustical short-comings and is a relatively inexpensive alternative to physical modifications of the enclosures. One critical benefit of active architecture is the controlled variability of acoustics. Although many improvements have been made over the last 60 years in the quality and usability of active acoustics, some problems still persist and the acceptance of this technology is advancing cautiously. McGill's Virtual Acoustic Technology (VAT) offers new solutions in the key areas of performance by focusing on the electroacoustic coupling between the existing room acoustics and the simulation acoustics. All control parameters of the active acoustics are implemented in the Space Builder engine by employing multichannel parallel mixing, routing, and processing. The virtual acoustic response is created using low-latency convolution and a three-way temporal segmentation of the measured impulse responses. This method facilitates a sooner release of the virtual room response and its radiation into the surrounding space. Field tests are currently underway at McGill University involving performing musicians and the audience in order to fully assess and quantify the benefits of this new approach in active acoustics.

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Authors and Affiliations

Wiesław Woszczyk
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Abstract

The paper concerns the problem of choosing a criterion for transmission line when lumped parameters analysis is required. First, the formal introduction of transmission line scheme is presented. Secondly, a new criterion for lumped-parameter analysis of transmission line is proposed. The criterion has clear physical meaning and simple mathematical form. The proposed criterion takes into account not only wave length, but also the dissipation of transmission line. The criterion can be easily adjusted to some requirements, such as needed level of no-load output voltage change.

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Authors and Affiliations

D. Spałek
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Abstract

Because of the value of time, investors are interested in obtaining economic benefits rather early and at a highest return. But some investing opportunities, e.g. mineral projects, require from an investor to freeze their capital for several years. In exchange for this, they expect adequate remuneration for waiting, uncertainty and possible opportunities lost. This compensation is reflected in the level of interest rate they demand. Commonly used approach of project evaluation – the discounted cash flow analysis – uses this interest rate to determine present value of future cash flows. Mining investors should worry about project’s cash flows with greater assiduousness – especially about those arising in first years of the project lifetime. Having regard to the mining industry, this technique views a mineral deposit as complete production project where the base sources of uncertainty are future levels of economic-financial and technical parameters. Some of them are more risky than others – this paper tries to split apart and weigh their importance by the example of Polish hard coal projects at the feasibility study. The work has been performed with the sensitivity analysis of the internal rate of return. Calculations were made using the ‘bare bones’ assumption (on all the equity basis, constant money, after tax, flat price and constant operating costs), which creates a good reference and starting point for comparing other investment alternatives and for future investigations. The first part introduces with the discounting issue; in the following sections the paper presents data and methods used for spinning off risk components from the feasibility-stage discount rate and, in the end, some recommendations are presented.

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Authors and Affiliations

Piotr W. Saługa
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Abstract

Nowadays, an orthomap destined for different purposes can be created from High Resolution Satellite (HRS) images using IKONOS, QuickBird and other satellite imageries having Ground Sampling Distance (GSD) lower than I m. The orthomap is one of the main sources for establishing GIS. Accuracy of the orthomap depends first of all on the parameters of Ground Control Points (GCPs) (the forms, number, accuracy and their distribution). In order to reduce the cost and number of GCP field measurements, the block of HRS images has been proposed. The accuracies of determined points in the block of HRS images are affected by the mathematical model used to build a block. The paper presents a general algorithm of bundle block adjustment model of HRS images using Keplerian parameters. In order to overcome strong correlation among exterior orientation elements of HRS images that causes the normal equation ill-conditioned, the ridge-stein estimator and orbital addition constraints have been proposed.
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Authors and Affiliations

Luong Chinh Ke
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Abstract

The European reference frame ETRF2000 was introduced on the territory of Poland on 1 July 2013, named PL-ETRF2000, as a result of the appropriate measurement campaign 2008-2011. The new PL-ETRF2000 reference frame has replaced the previously used PL-ETRF89 frame, which had more than 10 years of history in Poland until 2013, implemented in almost all geodetic and cartographic “products”, in geodetic networks, economic map systems and databases. The relationship of the new reference frame with the previously used PL-ETRF89 frame has become an important practical issue. Currently, all position services of the ASG-EUPOS (Active Geodetic Network – EUPOS) system use only the PL-ETRF2000 reference frame, which also results from the relevant legal and technical regulations. The relationships between the frames was considered in two aspects: “theoretical”, expressed by conformal (Helmert, 7-parameter) transformation, and “empirical”, based on an interpolation grid that allows to take into account local distortions of the PL-ETRF89 frame. The estimation of the parameters of the conformal transformation model was based on 330 points of the POLREF network, while to create an interpolation grid approximately 6500 points of the old triangulation network were additionally used, after new adjustment in PL-ETRF200 reference frame. Basic algorithms for the transformation between two frames and mapping systems are implemented in the new version of the TRANSPOL program, which is available on the web ( www.gugik.gov.pl).
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Bibliography

Balcerzak, J. (1994). Odwzorowanie Gaussa-Krügera w szerokiej 12° strefie dla obszaru Polski. IX Szkoła Kartograficzna. Komorowo, 10–14.10.1994.

Bosy, J. (2011). Weryfikacja wyników integracji podstawowej osnowy geodezyjnej na obszarze kraju ze stacjami referencyjnymi systemu ASG-EUPOS. Wrocław, 30.11.2011. Raport dla GUGiK Warszawa.

Deakin, R.E. (1998). 3D Coordinate transformations. Survey. Land Inf. Systems. 58, 4, pp. 223–234.

Deutsch, R. (1965). Estimation Theory. Englewood Cliffs: Prentice-Hall, Inc.

Jaworski, L. (2011). Zintegrowanie podstawowej osnowy geodezyjnej na obszarze Polski ze stacjami referencyjnymi systemu ASG-EUPOS ETAP IV. Opracowanie i wyrównanie obserwacji GNSS. Raport CBK dla GUGiK, lipiec 2011, Warszawa (Pomiary wykonane przez konsorcjum firm geodezyjnych).

Hausbrandt, S. (1971). Rachunek wyrównawczy i obliczenia geodezyjne. Tom I i II. Warszawa: PPWK. Transformation between the PL-ETRF89 and PL-ETRF2000 frames 19

Kadaj, R. (2001). Formuły odwzorowawcze i parametry układów współrzędnych (Mapping formulas and parameters of coordinate systems). Wytyczne Techniczne G-1.10. GUGiK 2001, ISBN-83-239- 1473-7.

Kadaj, R. and Świętoń, T. (2012). TRANSPOL wersja 2.06 – program do transformacji współrzędnych i wysokości w państwowym systemie odniesień przestrzennych – metody, algorytmy i opis programu (TRANSPOL version 2.06 – a program for the transformation of coordinates and heights in the state system of spatial references – methods, algorithms and description of the program). Internet publication of GUGiK – Head of the Office of Geodesy and Cartography, www.gugik.gov.pl.

Kadaj R. (2013). Skutki metryczne zmiany układów odniesienia: PL-ETRF89 na PL-ETRF2000 oraz PLKRON86- NH na PL-EVRF2007-NH w obszarze Polski (Metric effects of change of reference systems: PL-ETRF89 on PL-ETRF2000 and PL-KRON86-NH on PL-EVRF2007-NH in the area of Poland). In conf. Sekcji Geod. Sat. Komitetu Badań Kosmicznych i Satelitarnych PAN “Satelitarne metody wyznaczania pozycji we współczesnej geodezji i nawigacji”. AGH, Cracow, 24–27.09.2013.

Kozakiewicz, W. (1998). Wyrównanie pierwsza klasa. Geodeta, no. 2(33).

Liwosz, T., Rogowski, J., Kruczyk, M. et al. (2011). Wyrównanie kontrolne obserwacji satelitarnych GNSS wykonanych na punktach ASG-EUPOS, EUREF-POL, EUVN, POLREF i osnowy I klasy wraz z ocena wyników. Katedra Geodezji i Astronomii Geodezyjnej Wydział Geodezji i Kartografii Politechnika Warszawska. Warszawa, 15.12.2011. Raport dla GUGiK Warszawa.

Watson, G.A. (2006). Computing Helmert transformation. J. Comput. Appl. Math., 197, 387–394.

Zawadzki, J. (2011). Metody geostatyczne (Geostatic methods).Warszawa: Oficyna Wydawnicza Politechniki Warszawskiej.
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Authors and Affiliations

Roman Kadaj
1
ORCID: ORCID

  1. Rzeszów University of Technology, Rzeszów, Poland
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Abstract

This article discusses the most important issues regarding the implementation of digital algorithms for control and drive technology in industrial machines, especially in open mining machines. The article presents the results of tests in which the algorithm and drive control parameter settings were not selected appropriately for voltage-fed induction motors, and where the control speed was not verified by any of the available motoring or simulation methods. We then show how the results can be improved using field-oriented control algorithms and deep parameters analysis for sensorless field-oriented performance.
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Bibliography

[1] Kaczynski P., Czmochowski J., Analysis of causes for cracks in the connection of the swivel drawbar with crawler beam of the feeder vehicle, Mechanical Faculty, Wrocław University of Technology, Mining and Geoengineering, Book 2, no. 33, pp. 169–177 (2009).
[2] Sokolski P., Sokolski M., Evaluation of resistance to catastrophic failures of large-size caterpillar chain links of open-pit mining machinery, Eksploatacja i Niezawodnosc – Maintenance and Reliability 2014, vol. 16, no. 1, pp. 80–84 (2014).
[3] Anuszczyk J., Jabłonski M., Modification of the sensorless algorithm for controlling the drives of the tracks of the ZGOT Roller, Mining Institute of the Wrocław University of Technology, no. 112, pp. 69–76 (2005).
[4] Anuszczyk J., Jabłonski M., Research of electromechanical power units of the ZGOT, International Congress of Surface Mining, Bełchatów (2009).
[5] Kanczewski P., Kowalczyk P., ZGOT-15400.120 first Polish 200,000, Scientific work of the Mining Institute PWr. III International Congress of Lignite Mining, Bełchatów, pp. 213–221 (2002).
[6] Jabłonski M., Borkowski P., Replacement of control systems with implementation of digital inverter drive technology in surface mining machines, Conference KOMTECH 2020, to be published.
[7] Paszek W., Dynamic of alternating current electrical machines, Helion, Gliwice (1998).
[8] Pełczewski W., Krynke M., Variable State Method in Drive System Analysis, WNT, Warszawa (1984).
[9] Tunia H., Kazmierkowski M., Automation of converter dries systems, PWN, Warszawa (1987).
[10] Technical documentation, engineering manual and compendium for SIMOVERT MASTERDRIVES, Automation and Drives, Variable-Speed Drive Systems, Erlangen 1999-2012, Siemens AG (2020).
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[12] Jabłonski M., Analysis of functional parameters and modification of control algorithms of field-oriented inverter drive with induction motor, PhD., Faculty of Electrical Engineering, Electronics, Computer Science and Automation PŁ, Łódz (2006).
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Authors and Affiliations

Mariusz Jabłoński
1
Piotr Borkowski
1
ORCID: ORCID

  1. Lodz University of Technology, Poland
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Abstract

Ventilation rate is a physical index that is strictly controlled during cigarette manufacturing because an abnormal ventilation rate can affect the release of mainstream smoke, tar, and other components harmful to human health. Therefore, the standard rod is used for measuring the ventilation rate, which necessitates accurate and effective periodic inspections. In this study, we designed and built a set of special tobacco ventilation rate standard rods to assess the standard device during its verification period and used a digital thermal flowmeter as the flow standard.We determined the micro-pressure adjustment interval through fluid simulation, and conducted an experimental verification based on the simulation results. At the adjustment point where the differential pressure value was 0 Pa, the period verification device was tested under the standard values of 27.38%, 58.83%, and 71.95%. The results show that the measurement errors of the device are –0.42%, 0.55%, and –0.13% respectively, which all meet the verification regulation requirements and indicate that the device is applicable in practical situations.
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Authors and Affiliations

Jiacheng Hu
1
Ying Sha
1
Jinhui Cai
1
Ying Liu
2
Suijun Liu
2

  1. China Jiliang University, NO.258 XueYuan Street, Hangzhou, China
  2. Nanyang Cigarette Factory of Henan China Tobacco Industry, No. 6 Xinhua East Road, Nanyang, China

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