Nauki Techniczne

Bulletin of the Polish Academy of Sciences: Technical Sciences


Bulletin of the Polish Academy of Sciences: Technical Sciences | 2007 | vol. 55 | No 4 |


Extraction of the foetal electrocardiogram from single-channel maternal abdominal signals without disturbing its morphology is difficult. We propose to solve the problem by application of projective filtering of time-aligned ECG beats. The method performs synchronization of the beats and then employs the rules of principal component analysis to the desired ECG reconstruction. In the first stage, the method is applied to the composite abdominal signals, containing maternal ECG, foetal ECG, and various types of noise. The operation leads to maternal ECG enhancement and to suppression of the other components. In the next stage, the enhanced maternal ECG is subtracted from the composite signal, and this way the foetal ECG is extracted. Finally, the extracted signal is also enhanced by application of projective filtering. The influence of the developed method parameters on its operation is presented.

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One of the prime tool in non-invasive cardiac electrophysiology is the recording of an electrocardiographic signal (ECG) which analysis is greatly useful in the screening and diagnosis of cardiovascular diseases. However, one of the greatest problems is that usually recording an electrical activity of the heart is performed in the presence of noise. The paper presents Bayesian and empirical Bayesian approach to problem of weighted signal averaging in time domain which is commonly used to extract a useful signal distorted by a noise. The averaging is especially useful for biomedical signal such as ECG signal, where the spectra of the signal and noise significantly overlap. Using the methods of weighted averaging are motivated by variability of noise power from cycle to cycle, often observed in reality. It is demonstrated that exploiting a probabilistic Bayesian learning framework leads to accurate prediction models. Additionally, even in the presence of nuisance parameters the empirical Bayesian approach offers the method of theirs automatic estimation which reduces number of preset parameters. Performance of the new method is experimentally compared to the traditional averaging by using arithmetic mean and weighted averaging method based on criterion function minimization.

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A new class of positive hybrid linear systems is introduced. The solution of the hybrid system is derived and necessary and sufficient condition for the positvity of the class of hybrid systems are established. The classical Cayley-Hamilton theorem is extended for the hybrid systems. The reachability of the hybrid system is considered and sufficient conditions for the reachability are established. The considerations are illustrated by a numerical example.

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In the paper an application of differential evolution algorithm to design digital filters with non-standard amplitude characteristics is presented. Three filters with characteristics: linearly growing, linearly falling, and non-linearly growing are designed with the use of the proposed method. The digital filters obtained using this method are stable, and their amplitude characteristics fulfill all design assumptions.

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The main objective of this work is to provide a closed formula for the backward and symmetric solution of the 2-D implicit Roesser model. The relative forward and backward fundamental matrix is of fundamental importance in our approach. An algorithm for the

determination of the backward fundamental matrix sequense is also given.

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The paper discusses the stability problem for continuous time and discrete time positive systems. An alternative formulation of stability criteria for positive systems has been proposed. The results are based on a theorem of alternatives for linear matrix inequality (LMI) feasibility problem, which is a particular case of the duality theory for semidefinite programming problems.

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Two-dimensional (2D) positive systems are 2D state-space models whose state, input and output variables take only nonnegative values. In the paper we explore how linear matrix inequalities (LMIs) can be used to address the stability problem for 2D positive systems. Necessary and sufficient conditions for the stability of positive systems have been provided. The results have been obtained for most popular models of 2D positive systems, that is: Roesser model, both Fornasini-Marchesini models (FF-MM and SF-MM) and for the general model.

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The standard approach to the wave propagation in an inhomogeneous elastic layer leads to the displacement in a form of a product of a function of space and a harmonic function of time. This product represents the standing, and not the running wave. The part depending on the space variable is governed by the linear ordinary second order differential equation. In order to calculate the propagation speed in the present paper the inhomogeneous material is separated by a plane into two parts. Between the two inhomogeneous parts the virtual homogeneous elastic extra layer is added. The elasticity modulus and the mass density of the extra layer have the same values as the inhomogeneous material on the separation plane. In further calculations the extra layer is assumed to be infinitesimally thin. The virtual layer allows to decompose the motion into two waves: a wave running to the right and a wave running to the left. Energy conservation equation is derived.

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The paper explains the force induced by the electrostatic field on the electron as a recoil force. The starting point is the hypothesis that in the dynamic equilibrium with the vacuum, the electron simultaneously absorbs and emitts energy. With no external electrostatic field the radiation patterns of absorption and emission are assumed to be isotropic. The external electrostatic field induces anisotropy of the emission resulting in a recoil force. The paper presents a theoretical description of this force using a model of the angular power density pattern of the emission in the form of an ellipsoid. Calculations show that the total radiated power is extremely high. This radiation is compared with the electromagnetic radiation of the electron on the Bohr orbit in the idealized hydrogen atom. An analogous problem for gravitational forces is presented.

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The paper presents the theoretical background, computer model, laboratory measurements and SPICE simulation results of a 323 W, 1 MHz Class E inverter operating with an efficiency of 97%. The inverter is built around a CoolMOS transistor from Infineon Technologies. The transistor belongs to a new generation of high quality, optimized for low conduction losses and high speed switching power MOSFET-s. The presented computer model of Class E inverter is based on a state-space description and allows computing the inverter parameters for the optimum operation. Its validity has been confirmed experimentally. The SPICE simulation of the inverter has been also carried out in order to obtain better agreement between measurement and calculation results.

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A novel current-inversion type negative impedance converter (CNIC) is presented. It is built without the use of any resistors. Furthermore, a second-order low-pass filter based on this CNIC is also analysed. It shows a bandwidth of 50 MHz at 320 µW power consumption and 2 V supply voltage when realized in a 0.35 µm CMOS process.

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T. Kaczorek, Warsaw University of Technology

Deputy Editor-in Chief:

M.P. Kazmierkowski, Warsaw University of Technology
A. Rogalski, Division IV Technical Sciences PAN

Board of Co-editors:

Artificial and Computational Intelligence
S. Osowski and B. Sawicki, Warsaw University of Technology

BiomedicalEngineering and Biotechnology
A. Liebert and R. Maniewski, Institute of Biocybernetics and Biomedical Engineering PAN


Civil Engineering
L. Czarnecki, Building Research Institute, ITB, Warsaw

Control,Robotics and Informatics
J. Klamka and A. Babiarz, Silesian Technical University

A. Borkowski, Institute of Fundamental Technological Research PAN

Electronics, Telecommunication and Optoelectronics
M. Mrozowski and A. Lamęcki, Gdansk University of Technology

W. Woliński, Warsaw University of Technology

Mechanical and Aeronautical Engineering, Thermodynamics
A. Styczek, and A. Tylikowski, Warsaw University of Technology

MaterialsScience and Nanotechnology
B. Major and P. Czaja, Institute of Metallurgy and Materials Science PAN
T.A. Kowalewski and B. Blachowski, Institute of Fundamental Technological Research PAN

PowerSystems and Power Electronics
M.P. Kazmierkowski, Warsaw University of Technology

International Editorial Advisory Board

I.V. Alexandrov, Ufa State Aviation Technical University, Russia
R. Asthana, University of Wisconsin-Stout, Menomonie, USA
Xu Binshi, China Association of Plant Engineering, Beijing, P.R. China
F. Blaabjerg, Aalborg University, Denmark

C. Cecati, University of L’Aquila, Italy

A. Cichocki, RIKEN Institute, Tokyo, Japan

M. David, National Polytechnique de Toulouse, France
R. Ebner, Materials Centre Leoben, Leoben, Austria
E. Fornasini, University of Padova, Padova, Italy

L.G. Franquelo, University of Seville, Spain

M. Gad-el-Hak, Virginia Commonwealth University, Richmond, USA

D. van Gemert, Catholic University Leuven, KU Leuven, Belgium

L. Keviczky, Hungarian Academy of Sciences, Budapest, Hungary
V. Kučera, Czech Technical University in Prague, Prague, Czech Republic

R. Kennel, Technical University Munich, Germany

E. Levi, Liverpool John Moore University, UK
G. Maier, Technical University of Milan, Milan, Italy

K.F. Man, City University of Hong Kong,
H.A. Mang
, Austrian Academy of Sciences, Vienna, Austria
H. Mihashi, Tohoku University, Aoba-ku, Sendai, Japan
S. Mindess, University of British Columbia, Vancouver, Canada
D.A. Mlynski, University of Karlsruhe, Karlsruhe, Germany
A.S. Nowak, University of Michigan, Ann Arbor, USA

K. Ohnishi, Keio University, Yokohama, Japan
A. Öberg, Linköping University, Linköping, Sweden

W. Pedrycz, University of Alberta, Canada
S. Przemieniecki, University of South Florida, Tampa, USA
M. Razeghi, Northwestern University, Evanston, USA
J. Rodriguez, Technical University of Federico Santa Maria, Valparaiso, Chile
J.V. Sloten, Catholic University Leuven, Leuven, Belgium

B.M. Wilamowski, University of Auburn, Alabama, USA
W. Włosiński, Warsaw University of Technology, Warsaw, Poland
A.L. Yarin, University of Illinois at Chicago, USA

Du Xiangwan, Chinese Academy of Engineering, China
J. Żurada, Department of Computer Engineering, University of Louisville, USA


Editorial Office:
Pałac Kultury i Nauki,
Wydział IV PAN,
PL 00-901 Warszawa
tel.: +48(22) 182 60 45
Mrs Ewa Trojanowska

Instrukcje dla autorów

About the Journal

The Bulletin of the Polish Academy of Sciences: Technical Sciences (Bull.Pol. Ac.: Tech.) is published by the Division IV Engineering Sciences of the Polish Academy of Sciences. The journal is peer‐reviewed and is published both in printed and electronic form ( is established for the publication of original high quality papers from multidisciplinary Engineering sciences with the following topics preferred:

• Artificial and Computational Intelligence,
• Biomedical Engineering and Biotechnology,
• Civil Engineering,
• Control, Informatics and Robotics,
• Electronics, Telecommunication and Optoelectronics,
• Mechanical and Aeronautical Engineering, Thermodynamics,
• Material Science and Nanotechnology,
• Power Systems and Power Electronics.


General data:


Format of the journal – A4 printed and electronic form,

Paper type – thick (chalk overlay) paper,

Colourfulness – full colour at an extra charge,

The volume of the journal – 250 pages (ca 30 papers) + 4 cover pages,

Frequency of publication – quarterly,

ISSN: 0239-7528 (print version),

ISSN: 2300-1917 (on line version),

DOI: 10.24425/bpasts




Journal citation: Bull. Pol. Ac.: Tech.

ISO: Bull. Pol. Acad. Sci.-Tech. Sci.,


Acronym in the Editorial System: BPASTS


Journal Metrics:


JCR Impact Factor 2018:                                                                 1.361

5 Year Impact Factor: 1.323
SCImago Journal Rank (SJR) 2017:                                                 0.319
Source Normalized Impact per Paper (SNIP) 2017:                     1.005
CiteScore 2017:                                                                              1.27

The Polish Ministry of Science and Higher Education 2017:      25 points

Manuscript types:

Invited reviews presenting the state of the knowledge and/or devoted to novel topics,
• Refereed research papers reporting on original scientific or technological achievements,
• Refereed papers in special issues/sections serving as conference proceedings arranged by guest editors.


Submission Policy


All manuscripts submitted for publication should be original. Manuscripts published or under consideration for publication elsewhere should not be submitted and will not be considered. Submission of a paper implies that it has not been published previously, that it is not under consideration for publication elsewhere, a, nd that if accepted it will not be published elsewhere in the same form, in English or in any other language, without the written consent of the Publisher.


 Manuscript submission for review

The Bull. Pol. Ac.: Tech is now employing a Web-based manuscript submission and peer-review tracking system called Editorial System. Authors must submit their manuscript electronically on the web From this entry page, access can be obtained to all information required for the submission of a manuscript. First‐time users must create an Author’s account to obtain a user ID and password required to enter the system. All manuscripts receive individual identification codes that should be used in any correspondence with regard to the publication process. For the authors already registered in the Editorial System it is enough to enter their username and password to login as an author (Sign in). Author(s) will be notified about registration and manuscript review process by e-mail.
The manuscripts must be uploaded as a single PDF file.
If you experience difficulties with the manuscript submission website, please contact the Editorial Office of the Bull. Pol. Ac.: Tech (Mrs Ewa Trojanowska: or Mrs Anna Jurkiewicz of authors and their affiliation should be removed from the manuscripts for the review process in order to have a fair evaluation of their manuscript. All authors of the manuscript are responsible for its content; they must have agreed to its publication and have given the corresponding author the authority to act on their behalf in all matters pertaining to publication. The Corresponding Author is responsible for informing the coauthors of the manuscript status throughout the submission, review, and production process.

 Manuscript preparation

1. The manuscript should be written in clear and concise English (UK version).

2. For manuscript preparation please use the Word or LaTeX template available in the Information for Authors on

3. Please remember, that in the .pdf version of the manuscript uploaded in the Editorial System for evaluation process, author(s) name(s) and affiliation should be removed.

4. Authors should consult a recent issue of the journal for style if possible.

Manuscript decision and Proofs:

Manuscript evaluations are assigned one of four outcomes: Accept, Minor Revisions, Major Revisions, and Reject. Manuscripts requiring "Minor Revision" not require a second review. All manuscripts receiving a "Major Revision" evaluation must be subjected to a second review. Rejected manuscripts are given no further consideration. Normally, manuscripts that receive a "Major Revision" decision have only one additional chance for revision and the revised version should be uploaded to the Editorial System within six weeks. If the author(s) failed to make satisfactory changes, the manuscript is rejected. On acceptance, manuscripts are subject to editorial amendment to suit house style.

Transfer of Copyright Agreement

Once the paper is initially accepted, the authors are assumed to have transferred the copyright of the paper to the publisher. Please fill the Form, available on the webpage

Sign it, and add to the final version of the manuscript as separate .pdf file.

Proofs will be sent to the author (first named author if no corresponding author is identified of multi-authored papers) and should be returned within48 hours of receipt.

Fees for printing the article

The Bulletin of the Polish Academy of Sciences: Technical Sciences (Bull.Pol. Ac.: Tech.) is published in Open Access, which means that all articles are available on the internet to all users immediately upon publication free of charge for the readers. Authors are invited so a declaration that they are ready to cover the costs of printing their article. In addition, each color page will be charged an additional fee according to the current cost of printing. Otherwise, the paper will be printed in black-white.

More details see in Information for Authors:

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