Applied sciences

Bulletin of the Polish Academy of Sciences Technical Sciences

Description

The Bulletin of the Polish Academy of Sciences Technical Sciences is published bimonthly by the Division IV Engineering Sciences of the Polish Academy of Sciences, since the beginning of the existence of the PAS in 1952. The journal is peer‐reviewed and is published both in printed and electronic form. It 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.

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Journal Metrics:

JCR Impact Factor 2023:	1.2
5 Year Impact Factor 2022:	1.1
CiteScore 2023:	2.8
SCImago Journal Rank (SJR) 2023:	0.282
Source Normalized Impact per Paper (SNIP) 2023:	0.573
Ministry of Education and Science:	100 points

Abbreviated title: Bull. Pol. Acad. Sci. Tech. Sci.

ISSN

ISSN 2300-1917

Editorial Board 2023-2025

Editor-in-Chief:

A. Rogalski, Military University of Technology

Honorary (Past) Editor-in Chief:

T. Kaczorek, Warsaw University of Technology

M.P. Kaźmierkowski, Warsaw University of Technology

Deputy Editor-in-Chief:

B. Błachowski, Institute of Fundamental Technological Research PAN

M. Mrozowski, Gdansk University of Technology

Board of Topical Co-editors:

Artificial and Computational Intelligence

S. Osowski, B. Sawicki and T. Leś, Warsaw University of Technology

Biomedical Engineering and Biotechnology

D. Pijanowska, Institute of Biocybernetics and Biomedical Engineering PAN

Civil Engineering

L. Czarnecki, Building Research Institute, ITB, Warsaw

Ł. Sadowski, Wroclaw University of Science and Technology

Control, Robotics and Informatics

J. Klamka and A. Babiarz, Silesian Technical University

J. Stefanowski, Poznan University of Technology

Electronics, Telecommunication and Optoelectronics

M. Mrozowski and A. Lamęcki, Gdansk University of Technology

Mechanical and Aeronautical Engineering, Thermodynamics

B. Błachowski, Institute of Fundamental Technological Research PAN

G. Zboiński, Institute of Fluid-Flow Machinery PAN and University of Warmia and Mazury in Olsztyn

Materials Science and Nanotechnology

B. Major and P. Czaja, Institute of Metallurgy and Materials Science PAN

Power Systems and Power Electronics

J. Rąbkowski and M. Jasiński, Warsaw University of Technology

International Editorial Advisory Board

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 Sevilla, Spain

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

M. Giersig, Free University of Berlin, Germany

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

T.A. Kowalewski, Institute of Fundamental Technological Research PAN

E. Levi, Liverpool John Moore University, UK

G. Maier, Technical University of Milan, Milan, Italy

K.F. Man, City University of Hong Kong,

R. Maniewski, Institute of Biocybernetics and Biomedical Engineering PAN

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

M. Razeghi, Northwestern University, Evanston, USA

J. Rodriguez, University of Andres Bello, Santiago, Chile

J.V. Sloten, Catholic University Leuven, Leuven, Belgium

B.M. Wilamowski, University of Auburn, Alabama, USA

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 Nauk Technicznych PAN

Pl. Defilad 1

PL 00-901 Warszawa

Managing Editor:

Renata Podraza, e-mail: Renata.Podraza@pan.pl

Finance:

Katarzyna Łasak, e-mail: Katarzyna.Lasak@pan.pl

The Bulletin of the Polish Academy of Sciences Technical Sciences is an open access journal with all content available with no charge in full text version.

The journal content is available under the licencse CC BY 4.0 https://creativecommons.org/licenses/by/4.0/.

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Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access

1 Enhancing Mobile Eye-Tracking in Extreme Urban Lighting Conditions

Marta Rusnak , Zofia Koszewicz , Franciszek Hackemer , Izabela Garaszczuk , Andrew T. Duchowski , Rafał Karnicki

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e152709 | DOI: 10.24425/bpasts.2024.152709

Keywords: outdoor eye-tracking smart city data quality calibration sunlight

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Abstract

One of the methods for understanding residents' needs and socially improving urban spaces in terms of transportation, safety, landscape protection, and managing tourist traffic load is eye-tracking (ET). Researchers using mobile ET for outdoor studies face significant challenges, particularly due to sunlight affecting data quality. Existing solutions often overlook participant comfort. This article introduces a novel accessory designed for extreme lighting conditions, such as bright days, sunsets, and snowy or water-filled environments. The goal is to eliminate disruptions caused by uncontrolled sunlight on participants' eyes and enables studies in urban environments. A custom sun shield, designed for ETs based on spectacle frames, prioritizes both physical and psychological comfort. The lightweight shield is easy to install, minimally restricts the field of view, and does not interfere with eye-tracking components. It is cost-effective and suitable for DIY 3D printing. Control studies and field research confirmed its effectiveness, with feedback from over 100 users improving the final design. The shield enhances eye-tracking research credibility in sunny conditions, supports efficient calibration, and improves participant recruitment and well-being. Jakość danych znacząco wzrosła co obrazuje porównanie danych dotyczących sposobu detekcji źrenicy. Thanks to this solution, it will be possible to conduct research aimed at better understanding the behavior of city users, while ensuring their comfort and safety. It will also be possible to conduct research within the framework of so-called living labs. Importantly, studies show that the approach to designing subsequent mobile ETs based on IR should undergo significant modification.

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Authors and Affiliations

Marta Rusnak

Zofia Koszewicz

Franciszek Hackemer

Izabela Garaszczuk

Andrew T. Duchowski

Rafał Karnicki

2 Slip Compensation Technique In Five-Phase Induction Motors Drive System

Krzysztof Blecharz , Roland Ryndzionek , Paul Gondran , Imad Merzouk

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153223 | DOI: 10.24425/bpasts.2025.153223

Keywords: five-phase induction motor multi-phase motor open-loop control slip compensation scalar control

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Abstract

The article presents a slip compensation method for traditional scalar (V/f) control of a five-phase induction motor. The proposed control method uses the possibility of injecting the third harmonic of voltage to increase the motor’s electromagnetic torque. The solution is characterized by both the simplicity of scalar control and improved speed control efficiency. The paper presents the PLECS simulation results and describes the laboratory tests that were conducted. The several scenarios were performed with dedicated and self developed algorithm in a laboratory stand using a 5-phase induction motor.

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Authors and Affiliations

Krzysztof Blecharz

e-mail:

ORCID:

Roland Ryndzionek

e-mail:

ORCID:

Paul Gondran

Imad Merzouk

3 Experimental Studies on Reducing Permanent Magnet Losses Through Segmentation in a Fractional Slot PMSM Motor with High Power Density

Tomasz Wolnik , Tomasz Jarek , Jan Mikoś , Vitezslav Styskala

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153225 | DOI: 10.24425/bpasts.2025.153225

Keywords: eddy-current losses segmentation of permanent magnets high power density motors

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Authors and Affiliations

Tomasz Wolnik

e-mail:

ORCID:

Tomasz Jarek

e-mail:

ORCID:

Jan Mikoś

Vitezslav Styskala

4 DODGE: Congestion Control in Manet via Dragonfly Optimized Deep Learning Model

S Gladson , K Pandiarajan

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153231 | DOI: 10.24425/bpasts.2025.153231

Keywords: MANET congestion node deep learning dragon fly optimization bidirectional long-short term memory

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Abstract

A mobile ad hoc network (MANET) is a collection of mobile devices attached without infrastructure or central management. Network size increases rapidly, resulting in congestion, network delay, data packet loss, a drop in throughput, resulting in poor energy efficiency. Data should be mitigated based on the prediction of congestion. To resolve the problem of congestion, a novel Dragonfly Optimized Deep learning for conGestion Elimination (DODGE) technique has been proposed which predicts the congested node effectively. Initially, the Transmission Control Protocol (TCP), User Datagram Protocol (UDP) packets from the MANET environment has been pre-processed and the features are selected using Dragon Fly Optimization (DFO). The features that are selected from the DFO model has been provided to the Stacked Convolutional Neural Network combined with Bidirectional Long Short-Term Memory (SCNN-BiLSTM). The Deep Learning network will predict the congested node and if congestion is found, then the message will be displayed. The DODGE is simulated by using Network simulator2 (NS2) and a comparison is made between proposed DODGE and traditional approaches such as Hybrid Gravitational Fuzzy Neural Network (HGFNN), Quality of Service-Aware Distributed Congestion Control (QoS-ADCC), and ImprovedPriority Aware-Ad Hoc On-Demand Distance Vector (IPA-AODV) in terms of Packet Delivery Ratio (PDR), Delay (DE), Throughput (TP), Energy Consumption (EC), Latency (L), Detection Rate (DR), and Network Lifetime (NL). The proposed SCNN-BiLSTM improves the overall accuracy better than 10.05%, 6.59%, 3.26% Bidirectional Long ShortTerm Memory (BiLSTM), Deep Neural Network (DNN), Convolutional Neural Network (CNN) for predict the congested node in the shortest time.

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Authors and Affiliations

S Gladson

K Pandiarajan

5 Multilevel voltage source inverter with coupled reactors using coarsely quantized pulse amplitude modulation

Krzysztof Jakub Szwarc , Artur Cichowski , Paweł Szczepankowski , Janusz Nieznański , Ryszard Strzelecki

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | 153227 | DOI: 10.24425/bpasts.2025.153227

Keywords: multi-level inverter pulse amplitude modulation coupled reactors multi-pulse voltage source inverter

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Abstract

The paper discusses a multilevel voltage source inverter with coupled reactors (MVSI-CR). The output voltage is generated using the novel coarsely quantized pulse amplitude modulation (CQ-PAM). The AC voltage synthesis is realized by selecting and applying an appropriate collection of voltage vectors from the space-vector diagram. Integrating classical two-level inverters allows achieving modularity of the solution. The main advantage of the proposed approach is a very low switching-to-fundamental frequency ratio and a multistep quasisinusoidal output voltage. The paper includes a theoretical analysis, simulations, and laboratory test results.

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Authors and Affiliations

Krzysztof Jakub Szwarc

Artur Cichowski

e-mail:

ORCID:

Paweł Szczepankowski

e-mail:

ORCID:

Janusz Nieznański

Ryszard Strzelecki

e-mail:

ORCID:

6 Study on Properties of Multipole Switched Reluctance Motor Designed for Multichannel Operation – Single Channel Operation Analysis

Mariusz Korkosz , Piotr Bogusz , Jan Prokop , Piotr Zasowski

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153428 | DOI: 10.24425/bpasts.2025.153428

Keywords: multi-channel spectrogram switched reluctance motor critical drive increased redundancy drive single channel operation

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Abstract

The following paper deals with the multipole design of the switched reluctance motor (SRM). The design is intended to facilitate the four-channel operation of the motor. Due to multipole design of the rotor and multichannel operation abilities, there are numerous possible configurations for powering the poles in each phase. Analysis of selected such configurations was carried out, including multichannel (MC) operating conditions (e.g. single-channel operation (SCO)). A mathematical model of three-phase MC SRM is presented. The static electromagnetic torque characteristics were obtained together with the self- and mutual inductance characteristics. Selected laboratory test results are presented in the paper.

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Authors and Affiliations

Mariusz Korkosz

e-mail:

ORCID:

Piotr Bogusz

Jan Prokop

Piotr Zasowski

7 Analysis of the impact of the method of manufacturing the rotor on the parameters of an ACIPM machine

Mariusz Korkosz , Adrian Młot , Elżbieta Sztajmec , Karol Ryłło

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153433 | DOI: 10.24425/bpasts.2025.153433

Keywords: anisotropy cogging torque IPM motor electrical steel sheet torque ripple reduction

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Abstract

This article presents the technological problem related to the production of rotor with internal permanent magnet. Most often, the magnetic circuits of such rotors used in alternating current synchronous motors (AC IPM) are made of isotropic magnetic sheets. At this point, it should be noted that it is often not taken into account that each isotropic magnetic sheet exhibitssome anisotropy. This significantly affects the operational parameters of the brushless permanent magnet (PM) motor such as a cogging torque, electromagnetic torque ripples and an increase in induced voltage harmonics. To illustrate how important it is to properly design the rotor core, two rotors of the IPM motor were analysed in this work. In the first rotor solution, the minimisation of the anisotropy of the magnetic sheet was not taken into account, and the skew of the magnets was not used. In the second case of the IPM motor, the problem of anisotropy of the rotor magnetic circuit was minimised and an additional skew of the PMs was used. The obtained measurements and calculations of selected useful parameters of both rotor designs were compared with each other. Importantly, the conclusions and comments are extremely important for designers, assemblers and manufacturers of electrical machine components.

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Authors and Affiliations

Mariusz Korkosz

e-mail:

ORCID:

Adrian Młot

e-mail:

ORCID:

Elżbieta Sztajmec

Karol Ryłło

8 Modeling the responsive structures under external forces using an evolutionary algorithm

Szymon Jankowski , Waldemar Bober

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153432 | DOI: 10.24425/bpasts.2025.153432

Keywords: responsive architecture for urban planning shape changing structures morphing urban structures smart city structures evolutionary algorithm structure behavior modeling

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Abstract

The design of responsive structures has evolved significantly, establishing itself as an interdisciplinary field characterized by a fully customized ideation process. To streamline and unify this process, a novel method for modeling the behavior of rod-like responsive structures using an evolutionary algorithm is introduced. The proposed mathematical framework leverages key geometric and physic parameters to control the generative process, enabling adaptability and fluidity in form development. By employing an evolutionary algorithm, the method offers an alternative to conventional rigid and repetitive morphing models, providing flexibility and innovation in responsive design outcomes. The developed model supports independent learning and fosters originality in solutions at both architectural and urban scales. Moreover, the presented methodology serves as the foundation upon which the authors developed the model, enabling its application across a wide spectrum of responsive structures for users. This paper addresses challenges in spatial modeling, behavioral algorithms, and the implementation of responsive architecture, presenting the author’s innovative model for rod-like responsive structures alongside performance analysis. The methodology demonstrates promising results in terms of adaptability and efficiency, with potential for further refinement to enhance speed and output quality. Research also describes challenges and risks for further development of responsive models implementation.

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Authors and Affiliations

Szymon Jankowski

Waldemar Bober

9 On optimization of an adaptive pneumatic impact absorber – the innovative rescue cushion

Rami Faraj , Błażej Popławski , Dorian Gabryel , Grzegorz Mikułowski , Rafał Wiszowaty

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153436 | DOI: 10.24425/bpasts.2025.153436

Keywords: adaptive airbag adaptive impact absorption inflatable structure pneumatic absorber rescue cushion

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Abstract

The paper states a complex study on the adaptive rescue cushion and concerns a problem of efficient impact mitigation, which is present during evacuation or assurance of people conducted by fire brigades. In order to minimize negative effects of person’s fall from height an airbag system is applied. Unfortunately, until now only passive solutions have been used. As a result, loads acting on a landing person were not minimized, because passive systems are designed for predefined, extreme conditions. Since the authors proposed to introduce adaptation mechanisms into the rescue cushion, a number of issues arose. They include construction and control of release vents, taking into account the inaccuracies of estimated impact parameters, and optimization of the venting area in case the evacuated person lands outside the airbag’s center. All these problems were addressed within this paper and described in detail. Discussion on the system adaptation and its optimization was preceded by experimental validation of a numerical model. The energy absorbing capabilities of widely used passive rescue cushions were significantly enhanced as a result of the conducted research.

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Authors and Affiliations

Rami Faraj

e-mail:

ORCID:

Błażej Popławski

Dorian Gabryel

Grzegorz Mikułowski

Rafał Wiszowaty

10 Three-Axis Forces and Torque Sensor

Paweł Młotek , Piotr Mynarek , Marcin Kowol

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153437 | DOI: 10.24425/bpasts.2025.153437

Keywords: three-axis force and torque sensor optical measurement of force and torque STM microcontroller structural analysis

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Abstract

This paper describes research on a prototype of a multi-axis force and torque sensor dedicated to the support system of a telescopic camera crane arm. Based on studies conducted on an actual telescopic camera crane arm., the requirements that the sensor must meet to enable precise control of the drives in two working axes of the telescopic camera crane arm were defined. In the developed sensor, a method for measuring forces and torques using an optical displacement sensor was proposed. A simplified sensor prototype was made to verify the assumptions, and measurement tests were carried out. Additionally, the paper presents a CAD model of the sensor using an elastic pin, based on which a numerical model was developed, and calculations of displacements and mechanical stresses were performed.

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Authors and Affiliations

Paweł Młotek

Piotr Mynarek

Marcin Kowol

e-mail:

ORCID:

11 Investigation of the Temperature Impact on the Operation of a Nonlinear Electromagnetic Vibration Energy Harvester

Marcin Kulik , Rafał Gabor

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153836 | DOI: 10.24425/bpasts.2025.153836

Keywords: energy harvesting nonlinear electromagnetic energy harvester temperature coefficients frequency response dynamic analysis

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Abstract

This paper presents a detailed study on the impact of temperature on the performance of a nonlinear electromagnetic vibration energy harvester, which is applied in autonomous power systems. The variability of material properties under the influence of temperature, such as stiffness, damping, and magnetic induction, significantly affects the operational characteristics of the device. A mathematical model accounting for these factors, including linear and quadratic temperature coefficients, optimized using a genetic algorithm, is presented in the article. The simulation results were compared with experimental data, showing good agreement, particularly in the range of frequency bandwidth and output voltage. It was demonstrated that higher temperatures lead to a reduction in mechanical and magnetic stiffness, resulting in decreased energy conversion efficiency.

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Authors and Affiliations

Marcin Kulik

Rafał Gabor

e-mail:

ORCID:

12 The Fast Type-IV Discrete Sine Transform Algorithms for Short-Length Input Sequences

Marina Polyakova , Anna Witenberg , Aleksandr Cariov

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153827 | DOI: 10.24425/bpasts.2025.153827

Keywords: discrete sine transform matrix factorization fast algorithms computational complexity digital signal processing

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Abstract

The fast algorithms of discrete sinusoidal transform of the fourth type (DST-IV) for small-length input data in the range of lengths from 2 to 9 are developed. Fast algorithms for short input data sequences are subsequently used as building blocks for designing fast algorithms of large-sized discrete transforms. Applying the fast DST-IV algorithms for small-size block processing can reduce overall system complexity and delay, allowing detailed signal processing. As a result of the literature review, two main approaches to developing fast discrete sine transform (DST) algorithms were identified, namely, the polynomial algebraic approach and the matrix factorization approach. In the paper, the last approach is exploited. A matrix-vector product expression of the DST-IV is the starting point for designing the fast algorithms. Then based on the repetition and arranging of the matrix elements, the factorization of the matrices of coefficients of DST-IV is produced to reduce computational complexity. The correctness of the obtained algorithmic solutions was justified theoretically using a strict mathematical background of each of them. The elaborated algorithms were then further tested using MATLAB R2023b software to finally confirm their performance. The resulting factorizations of the DST-IV matrices reduce the number of multiplications by 63% but increase the number of additions by 8% on average in the range of signal sample numbers from 3 to 9. It has been observed that for even-length input sequences, the reduction in the number of multiplications is not as significant as for odd-length sequences. For some other well-known discrete trigonometric transforms (discrete Fourier transform, discrete Hartley transform) the opposite situation holds. The proposed DST-IV fast algorithms do not limit the length of the input data sequence to powers of two or three. The data flow graphs constructed for the proposed algorithms reveal their modular space-time structure suitable for VLSI implementation.

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Authors and Affiliations

Marina Polyakova

Anna Witenberg

Aleksandr Cariov

13 Description and comparison of fault detection algorithms based on a selected building automation device

Sandra Włostowska , Bartłomiej Kawa , Piotr Borkowski

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153832 | DOI: 10.24425/bpasts.2025.153832

Keywords: fault detection machine learning building automation smart-metering

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Abstract

The article compares selected classification algorithms and those dedicated to anomaly detection. The models used temperature measurements in four rooms simulated in the Matlab Simscape environment as test signals. The empirical part of the work consists of two parts. In the first one, an example data from the simulated building heating model object, models were built using unsupervised and supervised machine learning algorithms. Then, data from the facility was collected again with changed parameters (failures occurred at times other than the test ones, and the temperature patterns differed from those recorded and used to train the models). The algorithms' effects and test signals (temperature changes) were saved in the database. The obtained results were presented graphically in the Grafana program. The second part of the work presents a solution in which the analysis of the operating status of the heating system takes place in real time. Using an OPC server, data was exchanged between the Matlab environment and the database installed on a virtual machine in the Ubuntu system. The conclusions present the results and collect the authors' suggestions regarding the practical applications of the discussed classification models.

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Authors and Affiliations

Sandra Włostowska

Bartłomiej Kawa

e-mail:

ORCID:

Piotr Borkowski

e-mail:

ORCID:

14 Strategic Optimal Control of Multi-Camera Trajectories for UAV Capture Using Entropy and Coverage Approaches

Khishigjargal Gonchigsumlaa , Young Il Kim , Kun Min Yeo , Seong Hee Park , Yong Tae Lee

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153828 | DOI: 10.24425/bpasts.2025.153828

Keywords: optimal control multi-camera trajectory unmanned aerial vehicle entropy maximization surveillance area

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Abstract

The widespread use of unmanned aerial vehicles (UAVs) has heightened the demand for effective UAV monitoring, particularly in protected areas. Current learning-based detection systems depend heavily on camera sensors’ ability to capture UAVs in surveillance areas; however, advanced camera control methods remain limited. This paper proposes determining multi-camera trajectories that maximize UAV capture probability, ensuring UAVs remain within the camera’s field of view for further analysis, such as detection methods from camera-shot images. For this purpose, stochastic modelling is considered in the control framework for optimizing surveillance camera trajectories to enhance the probability of capturing UAVs. Key control parameters are derived through classical probability evaluations of the model with maximizing the entropy and covering trajectory-based strategies are applied. The reliability of stochastic system modeling is empirically validated through comprehensive computational experiments. These findings demonstrate the model’s potential to enhance UAV capture rates through optimized camera trajectories and coverage efficiency, paving the way for future advancements in real-environment applications.

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Authors and Affiliations

Khishigjargal Gonchigsumlaa

Young Il Kim

Kun Min Yeo

Seong Hee Park

Yong Tae Lee

15 Digital PID controllers with fractional variable order techniques and two discrete-time operator variants

Dorota Mozyrska , Malgorzata Wyrwas , Piotr Oziablo

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153831 | DOI: 10.24425/bpasts.2025.153831

Keywords: fractional variable order operators PID controllers discrete-time optimization

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Abstract

This paper introduces a control strategy utilizing the Fractional Variable Order PID digital controller (FVOPID). We employ two variants of fractional discrete-time operators with variable order: the Grünwald-Letnikov type and its convolution version. We examine and compare the performance of both controllers types on a higher order plant. Parameter optimization is conducted using a particle swarm algorithm.

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Authors and Affiliations

Dorota Mozyrska

Malgorzata Wyrwas

Piotr Oziablo

16 Bending behaviour of thin-walled perforated channel beams with modified cross sectional shape – Part 2: analytical calculations and FEM

Paweł Jasion , Aleksandra M. Pawlak , Piotr Paczos , Michał Plust , Marcin Rodak

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153435 | DOI: 10.24425/bpasts.2025.153435

Keywords: thin-walled channel beams web perforations four-point bending structural stability bucklinganalysis

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Abstract

This article is the second part of a comprehensive research program investigating the structural performance of thinwalled channels with modified cross-sectional geometries. The study involved testing six beams, three of which featured perforated webs, while the other three had flat, solid webs. The beams were subjected to four-point bending tests to evaluate their load-bearing capacity. The first part of the research presented the results of experimental tests and finite strip analysis. This article will focus on finite element analyses and analytical calculations conducted in accordance with Eurocode 3 guidelines and the principle of minimizing potential energy. The study provides several significant contributions: it integrates experimental, numerical, and theoretical methods to deliver a thorough evaluation of beam performance. The finite element method (FEM) simulations offer precise modeling of complex stress and strain states, while analytical calculations supply a solid theoretical foundation for interpreting structural behavior. The research demonstrates that web perforation, while reducing critical and maximum forces, also results in considerable weight savings, enhancing material efficiency. Additionally, the division of the research into two articles ensures clarity and accessibility, with this second part dedicated to detailed FEM and analytical results, thereby facilitating both academic understanding and practical engineering applications.

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Authors and Affiliations

Paweł Jasion

e-mail:

ORCID:

Aleksandra M. Pawlak

e-mail:

ORCID:

Piotr Paczos

e-mail:

ORCID:

Michał Plust

e-mail:

ORCID:

Marcin Rodak

17 Three-factor assessment of rutting factor of modified asphalt binders and mastics in the ageing process

Marta Mielczarek , Karol Andrzejczak , Mieczysław Słowik

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153833 | DOI: 10.24425/bpasts.2025.153833

Keywords: polymer modified bitumen rutting factor asphalt mastic maintenance parameter Multiple Stress Creep and Recovery test (MSCR) multi-factorial experimental design

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Abstract

This paper discusses the research and multivariate analyses of rheological properties of asphalt binders and mastics containing various mineral fillers and SBS copolymer-modified bitumen. In the experimental design employed, three types of mineral filler were used: limestone, basalt or granodiorite. For the purpose of determining the effect of ageing processes on the rheological properties of the obtained mastics, all asphalt binders tested were subjected to short-term (technological) ageing simulated under laboratory conditions using the RTFOT method. The main aim of this study was to evaluate the rutting resistance of modified binders and asphalt mastics depending on such factors as: the type of mineral filler, the percentage of SBS copolymer, temperature, and the influence of the ageing process. A three-way ANOVA was used to test for rutting resistance. The results of laboratory tests and statistical analyses made it possible to assess the significance of the factors examined in the research on the rutting resistance of asphalt binders and mastics, both before and after short-term ageing.

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Authors and Affiliations

Marta Mielczarek

Karol Andrzejczak

Mieczysław Słowik

18 Thermal Transfer Performance of Downhole Electric Heaters for In-Situ Pyrolysis in Tar-Rich Coal

Ying Tang , Li Xiao , Fan Yang , Xiaodan Wu , Zhan Su , Yue Zhang , Shixin Jiang , Peng Yang

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153839 | DOI: 10.24425/bpasts.2025.153839

Keywords: tar-rich coal in-situ heat injection downhole heater thermal performance well-wall stability

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Abstract

The performance of a large-size helical baffle heater in an in-situ operating is investigated using a numerical simulation method. It revealed that the fluid in the shell retains a spiral flow, and the output flow velocity is higher than in the surrounding area. However, the pitch design is rather big, resulting in a low-velocity flow zone on the backwind side. At 100 kW and 500 m³/h, the fluid flow is turbulent. 50 kW and 200 m³/h, the fluid remained laminar. As flow rate rose, the pressure of tar-rich coal formation grew dramatically. The wall temperature exhibited spiral plunger at the inlet, but the bottom temperature was symmetrically distributed. Under low power and flow, Reynolds number change has a greater impact on the combination of Nusselt and Prandtl number. The wellbore experiences higher thermal loads during downhole heating, increasing the possibility of thermal damage dramatically. An increase in the heater shell length improves the total heat transfer performance. Conventional heaters often only heat the bottom formation. Therefore, while optimizing the construction, it is vital to ensure that the weight of heater itself does not exceed the tensile strength of cable, and consider shifting down the perforation outlet or lowering the outlet.

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Authors and Affiliations

Ying Tang

Li Xiao

Fan Yang

Xiaodan Wu

Zhan Su

Yue Zhang

Shixin Jiang

Peng Yang

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19 Few-shot medical image classification with simple shape and texture text descriptors using vision-language models

Michał Byra , Muhammad Febrian Rachmadi , Henrik Skibbe

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153838 | DOI: 10.24425/bpasts.2025.153838

Keywords: medical image classification vision-language models large language models few-shot learning

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Abstract

Deep learning methods are gaining momentum in radiology. In this work, we investigate the usefulness of vision-language models (VLMs) and large language models for binary few-shot classification of medical images. We utilize the GPT-4 model to generate text descriptors that encapsulate the shape and texture characteristics of objects in medical images. Subsequently, these GPT-4 generated descriptors, alongside VLMs pre-trained on natural images, are employed to classify chest X-rays and breast ultrasound images. Our results indicate that few-shot classification of medical images using VLMs and GPT-4 generated descriptors is a viable approach. However, accurate classification requires to exclude certain descriptors from the calculations of the classification scores. Moreover, we assess the ability of VLMs to evaluate shape features in breast mass ultrasound images. This is performed by comparing VLM based results generated for shape-related text descriptors with the actual values of the shape features calculated using segmentation masks. We further investigate the degree of variability among the sets of text descriptors produced by GPT-4. Our work provides several important insights about the application of VLMs for medical image analysis.

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Authors and Affiliations

Michał Byra

Muhammad Febrian Rachmadi

Henrik Skibbe

20 The effect of continuous furnace load organization on temperature distribution during Controlled Atmosphere Brazing process

Sławomir Nadolny , Michał Rogalewicz , Adam Hamrol

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153837 | DOI: 10.24425/bpasts.2025.153837

Keywords: CAB aluminium heat exchangers brazing jig heat capacity heat conductivity

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Abstract

Aluminum Heat Exchangers (AHEXs) represent a continuously evolving production sector with applications across various industries. Their mass production utilizes continuous furnaces combined with the Controlled Atmosphere Brazing (CAB) process. The required heat is supplied through convection, conduction, and radiation. The degree of these interactions and their impact on the temperature achieved inside an AHEX can vary significantly depending on the type and mass of the load. The additional tooling, such as brazing jigs, also plays a crucial role. The design of these jigs, including their material and mass, is essential for the heat delivered inside an AHEX. The presence of brazing jigs can enhance conduction and radiation effects butmay also reduce convection. Due to use of different heating elements, varying lengths of continuous furnace chambers, and a nitrogen atmosphere control system, it is necessary to tailor the heating profile (furnace parameters) individually for each type of AHEX. The heating and cooling rates, as well as the duration in the elevated temperature, including the maximum temperature achieved inside an AHEX, are critical. This article presents a study on the impact of continuous furnace load organization (including load density and the presence of brazing jigs) on the temperatures achieved inside an AHEX.

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Authors and Affiliations

Sławomir Nadolny

Michał Rogalewicz

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Adam Hamrol

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21 Numerical analysis of seal force in contacting finger seal

Yuan Wei , Bowen Ma , Yi Li , Kai-Uwe Schröder

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153840 | DOI: 10.24425/bpasts.2025.153840

Keywords: bending flexxible beam contacting finger seal seal force eccentricity numerical analysis

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Abstract

Finger seal is a flexible sealing device widely used in high-temperature and high-pressure environments such as gas turbine. Its force analysis is the key to design and optimize the performance of finger seal. At present most of the research on force analysis of finger seal are focused on the whole seal ring, but each finger beam has a different contacting performance with the shaft. In this work, a new force analysis method for contacting finger seal is proposed, as well as the model of finger seal with or without eccentricity is established to analyze the force of a single finger beam. The curved flexible finger beam is transformed into a straight one loaded with a certain moment at the end of it. The force acting on the finger beam is studied and compared with the existing reference to demonstrate the feasibility of the analysis method. By changing each parameter of the finger seal, the relationship between seal force and structural parameter is investigated. It shows that this method is meaningful to the calculation results of seal force for single finger beam, and can promote the development of finger seal and make it further in engineering application.

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Authors and Affiliations

Yuan Wei

Bowen Ma

Yi Li

Kai-Uwe Schröder

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access

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23 Evaluation of TAERO UGV structural collision resistance using FEM analysis

Marek Nowakowski , Krzysztof Kosiuczenko

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e153431 | DOI: 10.24425/bpasts.2025.153431

Keywords: UGV structural collision resistannce crumple zone FEM analysis

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Abstract

The increasing adoption of unmanned platforms in sectors such as defense, agriculture, logistics highlights critical challenges, including traversal capability and collision resistance in unstructured terrain. This study investigates the crashworthiness of the developed TAERO UGV using Finite Element Method (FEM) analysis. The structural components critical to collision energy absorption were identified and analyzed. Descriptions of the LS-DYNA simulation model, material properties, and boundary conditions are provided. The primary objective was to numerically assess the bumper's performance during impact, considering the vehicle's operational speeds and crumple zone. An optimized numerical model was introduced to efficiently simulate vehicle collisions, focusing on key structural elements. Various scenarios were simulated to examine deformation, stress distribution, and bumper behaviour. Presented numerical analysis indicate that impacts with typical obstacles, like tree trunks in unstructured terrain, cause minimal damage, not affecting the vehicle's operational capability. Minor bumper damages, such as dents, varies with speed—more noticeable at higher speeds, while almost imperceptible up to 25 km/h. The stress distribution highlights the role of side components in energy absorption and structural deformation. The results confirm the vehicle's structural integrity and provide valuable data on its operation performance in complex environments during specialized missions.

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Authors and Affiliations

Marek Nowakowski

Krzysztof Kosiuczenko

24 Improving Testing of Multi-Agent Systems: An Innovative Deep Learning Strategy for Automatic, Scalable, and Dynamic Error Detection and Optimisation

Nour El Houda Dehimi , Zakaria Tolba , Mehdi Medkour , Anis Hadjadj , Stéphane Galland

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e154062 | DOI: 10.24425/bpasts.2025.154062

Keywords: multi-agent systems system-level testing error detection artificial intelligence techniques deep learning

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Abstract

In this paper, a novel method is introduced for automated, scalable, and dynamic identification of errors in various behavioural versions of a multi agent system under test, employing deep learning techniques. It is designed to enable accurate error detection, thus opening new possibilities for improving and optimising traditional testing techniques. The approach consists of two phases. The first phase is the training of a deep learning model using randomly generated inputs and predicted outputs generated from the behavioural model of each version. The second phase consists of detecting errors in the multi-agent system under test by replacing the predicted outputs with which the model is trained with execution outputs. The envisioned strategy is put into action through a real case study, which serves to vividly showcase and affirm its practical efficacy.

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Authors and Affiliations

Nour El Houda Dehimi

Zakaria Tolba

Mehdi Medkour

Anis Hadjadj

Stéphane Galland

25 Study and Design of a Coaxial Magnetic Gear with a High Torque Density in Telescopic Camera Cranes

Piotr Warmuzek , Janusz Kołodziej , Marcin Kowol

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e154203 | DOI: 10.24425/bpasts.2025.154203

Keywords: telescopic camera cranes magnetic gear magnetic torque torque ripple radial forces

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Abstract

Magnetic gears are slowly becoming a natural alternative to mechanical gears. Providing contactless, frictionless, and low-noise torque conversion, they are finding applications in renewable energy sources and electric vehicles, among others. This paper presents a comprehensive theoretical analysis with numerical calculations of a magnetic gear (MG) design for novel applications in telescopic camera cranes. Based on numerical simulations of selected MG variants, a potential transducer configuration was chosen that would meet the requirements of the drive transmission system - supporting the movement of the telescopic camera crane arm.

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Authors and Affiliations

Piotr Warmuzek

Janusz Kołodziej

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Marcin Kowol

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26 Numerical Simulation of Transient Start-up Characteristics in Pump-Driven Two-Phase Flow Systems

Nianyong Zhou , Jing Li , Jixiang Liu , Kaiming Liu , Feifei Wang , Lianghui Liu

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e154202 | DOI: 10.24425/bpasts.2025.154202

Keywords: pump two-phase flow heat transfer evaporative cold plate startup characteristic

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Abstract

The pump-driven two-phase flow system is widely used in electronic cooling due to its high heat transfer efficiency and stable temperature control. However, transient startup behaviors, crucial for reliability in dynamic thermal environments, remain poorly understood. This study addresses this gap by developing a simulation model using AMESim software with R134a as the working fluid, investigating the effects of heat load, pump speed, and cooling water temperature on startup dynamics. Results reveal three distinct startup types: Type I rising startup, Type II rising startup, and Type I falling startup. As the heat load increases from 2 kW to 5 kW, the system transitions from Type I to Type II, with the cold plate wall temperature decreasing by up to 27%. At 2 kW and 5 kW, the system exhibits Type I upward and Type II upward startup behaviors, respectively. Type II startup demonstrates reduced overshoot, enabling a quicker approach to quasi-steady state. At 2 kW, the system exhibits both single-phase and two-phase heat transfer, with the latter lowering the temperature by 2.26℃. Excessive subcooling can induce temperature oscillations within the evaporator. At a pump speed of 200 r/min, Type I upward startup is observed; however, increased speeds result in wall temperature overshoot. Furthermore, raising the cooling medium temperature from 10℃ to 40℃ elevates the evaporator wall temperature by 51.67%. By integrating quantitative metrics for overshoot, response time, and subcooling effects, this work provides actionable insights for optimizing pump-driven two-phase systems in high-heat-flux electronic cooling applications.

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Authors and Affiliations

Nianyong Zhou

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Jing Li

Jixiang Liu

Kaiming Liu

Feifei Wang

Lianghui Liu

27 Numerical simulation method of fork-flow condenser and the influence of fin structure characteristics

Kaiming Liu , Nianyong Zhou , Lianghui Liu , Benshi Han , Jing Li , Guanghua Tang , Jixiang Liu , Feifei Wang

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e154273 | DOI: 10.24425/bpasts.2025.154273

Keywords: condenser multiphase flow priodic iteration numerical simulation heat transfer characteristics

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Abstract

Many researchers have investigated numerical simulation methods for two-phase flow in condensers. Still, challenges persist due to these models' large size, complex structure, and multiphase flow fields. To address these issues, this paper employs a periodic iterative numerical simulation approach for ultra-long condensers, validating the method through experiments and advancing the numerical simulation technology for such models. The study emphasises the impact of structural changes on the refrigerant and air sides. Results indicate that the most minor error occurs when the number of iterations in the two-phase zone does not exceed three. Increasing the total number of refrigerant channels from 10 to 18 enhances heat transfer by 17.7% and condensation capacity by 10.6%. However, further increases in channel numbers lead to a significant rise in pressure drop, deteriorating heat transfer performance. The heat transfer and condensation capacity improve with the height-to-width ratio of the refrigerant channel, reaching optimal performance when the ratio is close to 1. Additionally, increasing the aspect ratio on the air side will improve the heat transfer and condensation rate of the condenser. However, when the aspect ratio reaches 4.53, further increases will lead to a decrease in the heat transfer coefficient and an increase in pressure drop.

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Authors and Affiliations

Kaiming Liu

Nianyong Zhou

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ORCID:

Lianghui Liu

Benshi Han

Jing Li

Guanghua Tang

Jixiang Liu

Feifei Wang

28 Signed Networks with Laplacian Feedback: Observability and Minimal Sensor Problem

Vijayakumar S. Muni , Kallu Vetty Muhammed Rafeek , Gudala Janardhana Reddy , Deena Sunil Sharanappa

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e154061 | DOI: 10.24425/bpasts.2025.154061

Keywords: multi-agent systems observability signed graph

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Abstract

In many multi-agent networks that evolve according to specific dynamical rules, our direct access is often limited to only a small subset of agents, known as “sensors.” The remaining agents in the network, whose states are entirely inaccessible, are referred to as “actuators.” If it is possible to retrieve the complete states of the actuators from the knowledge of the sensors’ states, the network is said to be “sensor– actuator observable”; otherwise, it is deemed unobservable. This research explores the analysis of sensor–actuator observability property (i.e., observable or unobservable) in networks where agent communications encompass both cooperation and competition (i.e., signed networks). It is assumed that the network’s agents continuously update their states within R under the Laplacian protocol. We simplify the Kalman’s and the PBH rank criteria for evaluating sensor–actuator observability property into several verifiable algebraic tests, emphasizing the significance of the system matrices’ spectral properties. This property is also examined from the perspective of the network’s graph topology. Sensor– actuator observability property is significantly influenced by the nature of agent communications and is often differs between signed and unsigned networks. However, we demonstrate that for a structurally balanced signed network, with specific set of sensors, it’s sensor–actuator observability property aligns with that of its unsigned variant. We present a formula utilizing Laplacian spectral information to determine the minimum number of sensors for an ensured sensor–actuator observable network. Applying the formula to path and cycle networks, it is found that paths are observable with one sensor, and cycles require two for observability.

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Authors and Affiliations

Vijayakumar S. Muni

Kallu Vetty Muhammed Rafeek

Gudala Janardhana Reddy

Deena Sunil Sharanappa

29 A flying start method for sensorless induction machine-based electric drives

Daniel Wachowiak

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e154206 | DOI: 10.24425/bpasts.2025.154206

Keywords: induction machine flying start speed observer sensorless drive DC injection

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Abstract

This paper presents an analysis of a proposed flying start method for sensorless electric drives based on an induction machine. The method introduces two stages. In the first stage, the rotor speed is estimated using the step response of the machine, which enables coarse estimation of the speed and direction of rotation, helping to reduce the initial slip. The second stage introduces an intermediate control system to facilitate the machine restart and assist the speed observer in converging. Simulation and experimental studies demonstrate that the method successfully restarts the machine with unknown initial rotor speed without exceeding the nominal current. The auxiliary control system fully excites a 5.5 kW machine within 300 ms during the flying start, after which it is possible to transition to the target control system.

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Daniel Wachowiak

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30 Processing and analysis of trolleybus traction data using LINQ technology

Andrzej Wilk , Mikołaj Bartłomiejczyk , Jacek Skibicki , Leszek Jarzębowicz , Dariusz R. Karkosinski , Łukasz Hupka , Jan Hupka , Paweł Kaczmarek , Natalia Karkosinska-Brzozowska

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e154144 | DOI: 10.24425/bpasts.2025.154144

Keywords: trolleybuses traction batteries exploatation and maintaining

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Abstract

The paper presents the processing and analysis of the recorded trolleybus data using the LINQ (Language Integrated Query) software technology. The trolleybus data acquisition system collects a huge amount of electromechanical data in real time during the vehicle operation. These data are used for the analysis in post-processing mode. In this paper, the data processing has been performed to assess the technical condition of trolleybus batteries. Selected standard query operators of the LINQ technology have been implemented in the Windows Presentation Foundation (WPF) application to process the data and to determine the charge and energy stored in the battery. The LINQ technology has been proven to be useful for analysing large amounts of data recorded from trolleybuses.

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Authors and Affiliations

Andrzej Wilk

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Mikołaj Bartłomiejczyk

Jacek Skibicki

Leszek Jarzębowicz

Dariusz R. Karkosinski

Łukasz Hupka

Jan Hupka

Paweł Kaczmarek

Natalia Karkosinska-Brzozowska

31 Strain-controlled uniaxial fatigue of an AA2519 aluminum alloy sheet

Łukasz Pejkowski , Maciej Kotyk

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e154271 | DOI: 10.24425/bpasts.2025.154271

Keywords: AA2519 aluminum alloy sheet metal fatigue life

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Abstract

This study provides a comprehensive investigationŁ of the uniaxial, strain-controlled fatigue behavior of an AA2519 aluminum-copper alloy. The alloy was characterized in the as-fabricated state. Three orientations relative to the rolling direction were used to determine the mechanical properties. The quasistatic strength and cyclic stress‒strain response of the AA2519 aluminum alloy for the examined cases were similar regardless of the rolling direction, although slight differences between them were noticeable. Similarly, the fatigue life was not strongly affected by the specimen orientation. The investigation also included fractographic analysis of the fracture surfaces, revealing differences between strain amplitude levels and specimen orientations. The experimental results obtained provide a good basis for engineering applications of the analyzed AA2519 alloy and offer a solid foundation for further research into the effect of heat treatment on the fatigue strength of the investigated alloy.

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Authors and Affiliations

Łukasz Pejkowski

Maciej Kotyk

32 Tribological properties of plasma sprayed NiAlAg-Ta-Cr₂O₃ composite lubrication coatings from room temperature to 750 C

Chengqi Yan , Xiaopeng Miao , Zhuying Jia , Fei Zhao , Yong Zhang

Bulletin of the Polish Academy of Sciences Technical Sciences | Early Access | e154275 | DOI: 10.24425/bpasts.2025.154275

Keywords: lubricating coatings plasma spraying silver tantalate wide temperature range

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Abstract

With the rapid advances in science and technology, the core parts and techniques in tribo-systems rely on the solidlubricating materials at wide-temperature range for durability, especially for designing and producing materials with low friction coefficient and high wear resistance over a wide temperature ranges. In this paper, a series of NiAl-Ag-Ta-Cr₂O₃ composite coatings with different contents of Ta and Ag were deposited by plasma spraying, their tribological properties at RT-750 C under dry sliding conditions were investigated by a ball-on-disk tribometer. The friction products and compositions of worn surface at different temperature were investigated. The deposited NiAl-Ag-Ta-Cr₂O₃ composite coatings exhibited excellent wear resistance at RT (10^-7 mm³ /N m), while the friction coefficients lower than 0.5 at RT to 750 C. The contents of Ta and Ag decided mechanical properties of coatings, and greatly affected the tribological properties by creating an tribo-film (lubricant film and glaze layer). NiAl-10Ag-5Ta-20Cr₂O₃ coating shows better tribological properties over all temperature, while the wear rate reduces to 5 58×10^-6 mm³ /N m at 750 C and the friction coefficient reduces to 0.21 at 600 C. The excellent lubrication and wear resistance of composite coatings at high temperatures are mainly attributed to the Ag acted as lubrication phase, and the top surface of wear track was covered with a smooth glaze layer, which consisted of Ag, Ta₂O₅, Cr₂O₃ and AgTaO₃. In addition, the lubrication mechanism of silver tantalate was also briefly discussed.

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Authors and Affiliations

Chengqi Yan

Xiaopeng Miao

Zhuying Jia

Fei Zhao

Yong Zhang

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