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Applied sciences

Bulletin of the Polish Academy of Sciences Technical Sciences

Content

Bulletin of the Polish Academy of Sciences Technical Sciences | 2023 | 71 | 1

Authors and Affiliations

Jacek Szafran
1
ORCID: ORCID
Alphose Zingoni
2
Maria Pia Repetto
3
Marcin Kamiński
1

  1. Lodz University of Technology, Al. Politechniki 6, 90-924 Łódź, Poland
  2. University of Cape Town, Department of Civil Engineering, Rondebosch 7701, South Africa
  3. University of Genoa, Department of Civil, Chemical and Environmental Engineering, Via Montallegro 1, 16145 Genoa, Italy
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Abstract

The paper demonstrates the potential of wavelet transform in a discrete form for structural damage localization. The efficiency of the method is tested through a series of numerical examples, where the real flat truss girder is simulated by a parameterized finite element model. The welded joints are introduced into the girder and classic code loads are applied. The static vertical deflections and rotation angles of steel truss structure are taken into consideration, structural response signals are computed at discrete points uniformly distributed along the upper or lower chord. Signal decomposition is performed according to the Mallat pyramid algorithm. The performed analyses proved that the application of DWT to decompose structural response signals is very effective in determining the location of the defect. Evident disturbances of the transformed signals, including high peaks, are expected as an indicator of the defect existence in the structure. The authors succeeded for the first time in the detection of breaking the weld in the truss node as well as proved that the defect can be located in the diagonals.
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Authors and Affiliations

Anna Knitter-Piątkowska
1
ORCID: ORCID
Olga Kawa
1
Michał Jan Guminiak
1

  1. Poznan University of Technology, Institute of Structural Analysis, Poland
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Abstract

The paper presents arch structures modeled by finite elements in which the nodes can be flexibly connected. Two-node curved elements with three degrees of freedom at each node were used. Exact shape functions were adopted to obtain stiffness and consistent mass matrices but they were modified by introducing rotational flexibility in the boundary nodes. Calculations of statics and dynamics of arches with different positions of flexible joints and different values of rotational stiffness of the joints were carried out.
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Authors and Affiliations

Magdalena Łasecka-Plura
1
ORCID: ORCID
Zdzisław Pawlak
1
ORCID: ORCID
Martyna Żak-Sawiak
1
ORCID: ORCID

  1. Poznan University of Technology, Institute of Structural Analysis, ul. Piotrowo 5, 60-965 Poznan, Poland
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Abstract

“Polyurea coatings as a possible structural reinforcement system” is a research project aimed at exploring possible applications of polyurea coatings for improving structural performance (including steel, concrete, wooden and other structures used in the construction industry). As part of the project, this paper focuses on evaluating the performance of bent reinforced concrete (RC) beams covered with a polyurea coating system. Easy polyurea application and its numerous advantages can prove very useful when existing RC structural elements are repaired or retrofitted. Laboratory tests of three types of RC beams with three different longitudinal reinforcement ratios were performed for the purposes of this paper. The tests were designed to determine the bending strength, performance and cracking patterns of the coated RC beams. In addition, a theoretical model was developed to predict the impact of the polyurea coating on the bending strength of the RC beams. On this basis, the effect of the coating on the bending strength and the performance of the coated beams at the ultimate limit state (ULS) was examined and analyzed. The results showed that the use of the polyurea coating has a positive impact on the cracking state of the RC beams subject to bending and little effect on their bending strength.
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Authors and Affiliations

Jacek Szafran
1
ORCID: ORCID
Artur Matusiak
1
Katarzyna Rzeszut
2
ORCID: ORCID
Iwona Jankowiak
3

  1. Department of Structural Mechanics, Faculty of Civil Engineering, Architecture and Environmental Engineering, Lodz University of Technology, Aleja Politechniki 6, 90-924 Łódź, Poland
  2. Institute of Building Engineering, Faculty of Civil and Transport Engineering, Poznan University of Technology, Piotrowo 5, 60-965 Poznan, Poland
  3. Institute of Civil Engineering, Faculty of Civil and Transport Engineering, Poznan University of Technology, Piotrowo 5, 60-965 Poznan, Poland
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Abstract

The analyses aim to determine aerodynamic force coefficients in the case of airflow around two smooth or rough cylinders positioned at different angles to the direction of wind velocity. Such systems, for instance, may be part of a tubular water slide. The results were compared with the values of the interference coefficient of the cylinders arranged in a row included in Eurocode EN 1991 part 4. The aerodynamic forces of the cylinder systems were determined on the basis of experimental tests conducted in a wind tunnel. To verify the above results, CFD (computational fluid dynamics) simulations were prepared. An important observation is that for the angle of yaw β = 0◦, the negative component of the lift force (lateral) fy is shown, while for the other cases, the situation is opposite and the lateral force points outside the gap (upward). The second is that the results of aerodynamic drag for rough cylinders arranged in a row and calculated according to EN 1991 part 4 may be underestimated. The flow around the pair of smooth cylinders is quite different from that of the rough ones, because during the experiment the first falls into the critical flow regime, while the second has supercritical characteristics.
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Authors and Affiliations

Agnieszka Padewska-Jurczak
1
ORCID: ORCID
Piotr Szczepaniak
1
ORCID: ORCID
Ryszard Walentyński
1

  1. Faculty of Civil Engineering, Department of Mechanics and Bridges, ul. Akademicka 5, 44-100 Gliwice, Poland
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Abstract

Scaffolding is equipment usually used at construction sites. A scaffolding structure is lightweight and made of elements used many times. The characteristics of scaffolding make it susceptible to dynamic actions present at the structure or occurring nearby. A scaffolding structure of medium size was subjected to analysis in this paper. The structure FEM model was loaded with single force harmonic excitation with various frequencies ranging from 1 Hz to 12 Hz applied in one of many selected points on the scaffolding façade. In the first step, natural frequencies and mode shapes of the analyzed structure were calculated. Then the full dynamic analysis was carried out to obtain maximum displacements of selected control points. The relation of excitation force frequency and location to the amplitudes of generated displacement was observed. It was found that low excitation frequencies close to the natural frequencies of the structure produced vibrations ranging to large areas of the scaffolding surface. Higher excitation frequencies are usually less propagated at the scaffolding but still may produce some discomfort to the structure users in the vicinity of the excitation force location. Scaffolding is equipment usually used at construction sites. A scaffolding structure is lightweight and made of elements used many times. The characteristics of scaffolding make it susceptible to dynamic actions present at the structure or occurring nearby. A scaffolding structure of medium size was subjected to analysis in this paper. The structure FEM model was loaded with single force harmonic excitation with various frequencies ranging from 1 Hz to 12 Hz applied in one of many selected points on the scaffolding façade. In the first step, natural frequencies and mode shapes of the analyzed structure were calculated. Then the full dynamic analysis was carried out to obtain maximum displacements of selected control points. The relation of excitation force frequency and location to the amplitudes of generated displacement was observed. It was found that low excitation frequencies close to the natural frequencies of the structure produced vibrations ranging to large areas of the scaffolding surface. Higher excitation frequencies are usually less propagated at the scaffolding but still may produce some discomfort to the structure users in the vicinity of the excitation force location.
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Authors and Affiliations

Jarosław Bęc
1
ORCID: ORCID
Ewa Błazik-Borowa
1
ORCID: ORCID
Jacek Szer
2
ORCID: ORCID

  1. Faculty of Civil Engineering and Architecture, Lublin University of Technology, Poland
  2. Faculty of Civil Engineering, Architecture and Environmental Engineering, Lodz University of Technology, Poland
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Abstract

The calculations of fuel tanks should take into account the geometric imperfections of the structure as well as the variability of the material parameters of the foundation. The deformation of the tank shell can have a significant impact on the limit state of the structure and its operating conditions. The paper presents a probabilistic analysis of a vertical-axis, floating-roof cylindrical shell of a tank with a capacity of 50000 m3 placed on stratified soil with heterogeneous material parameters. The impact of a random subsoil description was estimated using the Point Estimated Method (PEM). In this way, the number of analyzed FEM models was significantly reduced. This approach also makes it possible to assess the sensitivity of tank settlement and deformation to the changing foundation conditions.
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Authors and Affiliations

Kamil Żyliński
1 2
Jarosław Górski
1
ORCID: ORCID

  1. Faculty of Civil and Environmental Engineering, Gdansk University of Technology, Poland
  2. ERSYS, Poland
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Abstract

The paper concerns steel domes with regard to the special structures named tensegrity. Tensegrities are characterized by the occurrence of self-stress states. Some of them are also characterized by the presence of infinitesimal mechanisms. The aim of this paper is to prove that only tensegrity domes with mechanisms are sensitive to the change of the level of initial prestress. Two tensegrity domes are considered. In addition, a standard single-layer dome is taken into account for comparison. The analysis is carried out in two stages. Firstly, the presence of the characteristic tensegrity features is examined (qualitative analysis). Next, the behavior under static external loads is studied (quantitative analysis). In particular, the influence of the initial prestress level on displacements, effort, and stiffness of the structure is analyzed. To evaluate this behavior, a geometrically non-linear model is used. The model is implemented in an original program written in the Mathematica environment. The analysis demonstrates that for a dome with mechanisms, the adjustment of pre-stressing forces influences the static properties. It has been found that the stiffness depends not only on the geometry and properties of the material but also on the initial prestress level and external load. In the case of the non-existence of mechanisms, structures are insensitive to the initial prestress level.
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Authors and Affiliations

Paulina Obara
1
ORCID: ORCID
Maryna Solovei
1
ORCID: ORCID
Justyna Tomasik
1
ORCID: ORCID

  1. Faculty of Civil Engineering and Architecture, Kielce University of Technology, Poland
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Abstract

This paper attempts to conduct a comparative life cycle environmental analysis of alternative versions of a product that was manufactured with the use of additive technologies. The aim of the paper was to compare the environmental assessment of an additive-manufactured product using two approaches: a traditional one, based on the use of SimaPro software, and the authors’ own concept of a newly developed artificial intelligence (AI) based approach. The structure of the product was identical and the research experiments consisted in changing the materials used in additive manufacturing (from polylactic acid (PLA) to acrylonitrile butadiene styrene (ABS)). The effects of these changes on the environmental factors were observed and a direct comparison of the effects in the different factors was made. SimaPro software with implemented databases was used for the analysis. Missing information on the environmental impact of additive manufacturing of PLA and ABS parts was taken from the literature for the purpose of the study. The novelty of the work lies in the results of a developing concurrent approach based on AI. The results showed that the artificial intelligence approach can be an effective way to analyze life cycle assessment (LCA) even in such complex cases as a 3D printed medical exoskeleton. This approach, which is becoming increasingly useful as the complexity of manufactured products increases, will be developed in future studies.
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Authors and Affiliations

Ewa Dostatni
1
ORCID: ORCID
Anna Dudkowiak
1
ORCID: ORCID
Izabela Rojek
2
ORCID: ORCID
Dariusz Mikołajewski
2
ORCID: ORCID

  1. Institute of Material Technology, Poznan University of Technology, Piotrowo 3, 60-965 Poznan, Poland
  2. Institute of Computer Science, Kazimierz Wielki University, Chodkiewicza 30, 85-064 Bydgoszcz, Poland

Authors and Affiliations

Jianwei Wang
1 2
ORCID: ORCID
Deyun Chen
1

  1. College of Computer Science and Technology, Harbin University of Science and Technology, Harbin 150080, China
  2. College of Computer Science and Technology, Heilongjiang Institute of Technology, Harbin 150050, China
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Abstract

The paper presents a novel hybrid cuckoo search (CS) algorithm for the optimization of the line-start permanent magnet synchronous motor (LSPMSM). The hybrid optimization algorithm developed is a merger of the heuristic algorithm with the deterministic Hooke–Jeeves method. The hybrid optimization procedure developed was tested on analytical benchmark functions and the results were compared with the classical cuckoo search algorithm, genetic algorithm, particle swarm algorithm and bat algorithm. The optimization script containing a hybrid algorithm was developed in Delphi Tiburón. The results presented show that the modified method is characterized by better accuracy. The optimization procedure developed is related to a mathematical model of the LSPMSM. The multi-objective compromise function was applied as an optimality criterion. Selected results were presented and discussed.
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Authors and Affiliations

Łukasz Knypiński
1
ORCID: ORCID

  1. Poznan University of Technology, Institute of Electrical Engineering and Electronics, Piotrowo 3a, 60-965 Poznan, Poland
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Abstract

Business processes are omnipresent in nowadays economy: companies operate repetitively to achieve their goals, e.g., deliver goods, complete orders. The business process model is the key to understanding, managing, controlling, and verifying the operations of a company. Modeling of business processes may be a legal requirement in some market segments, e.g., financial in the European Union, and a prerequisite for certification, e.g., of the ISO-9001 standard. However, business processes naturally evolve, and continuous model adaptation is essential for rapid spot and reaction to changes in the process. The main contribution of this work is the Continuous Inductive Miner (CIM) algorithm that discovers and continuously adapts the process tree, an established representation of the process model, using the batches of event logs of the business process. CIM joins the exclusive guarantees of its two batch predecessors, the Inductive Miner (IM) and the Inductive Miner – directlyfollows-based (IMd): perfectly fit and sound models, and single-pass event log processing, respectively. CIM offers much shorter computation times in the update scenario than IM and IMd. CIM employs statistical information to work around the need to remember event logs as IM does while ensuring the perfect fit, contrary to IMd.
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Authors and Affiliations

Tomasz P. Pawlak
1
ORCID: ORCID
Bartosz Górka
1

  1. Institute of Computing Science, Poznan University of Technology, Poland

Authors and Affiliations

Mariusz Rząsa
1
ORCID: ORCID

  1. Opole University of Technology, Faculty of Electrical Engineering Automatic Control and Informatics, ul. Prószkowska 76, 45-758 Opole, Poland
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Abstract

Production is becoming more customer-focused as it departs from delivering standardized mass products to market segments, and the emerging Industry 4.0 technologies render this much easier than before. These technologies enable two-way information exchange with customers throughout all the steps of product development, particularly in terms of tailor-made products. This study aims at presenting proposals of implementing Industry 4.0 technologies into the process of tailored products, where the product is customized for the customer from the start and where adjustments are also made at the manufacturing stage. The study also aims to build a concept of intensification of customer contact and to improve the process flow by applying Industry 4.0 technologies. The study’s subject is tailor-made furniture production, with individually designed products that are manufactured and installed at a customer’s facilities. The company in the study operates on a small scale. The study employs a case study methodology that shows how the process can be improved in terms of real-time effective customer contact and process flow. The huge potential of 3D visualization as well as augmented and virtual reality technologies are also demonstrated. The study concludes with several directions for further development of existing technology solutions.
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Authors and Affiliations

Krzysztof Łukaszewicz
1
ORCID: ORCID
Wiesław Urban
1
ORCID: ORCID
Elżbieta Krawczyk-Dembicka
1
ORCID: ORCID

  1. Faculty of Engineering Management, Department of Production Management, Bialystok University of Technology, Wiejska 45A Street, 15-351 Białystok, Poland
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Abstract

The article presents a closed-form formula for solving a weakly singular surface integral with a linear current source distribution associated with the SIE-MoM formulation used for solving electromagnetic (EM) problems. The analytical formula was obtained by transforming the surface integral over a triangular domain into a double integral, and then directly determining formulas for the inner and outer integrals. The solution obtained is marked by high computational efficiency, high accuracy, and very simple implementation. The derived formula, in contrast to the currently available formulas, consists of quantities that have a clear and simple geometric interpretation, related to the geometry of the computational domain.
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Authors and Affiliations

Anna Grytsko
1
ORCID: ORCID
Piotr Słobodzian
1
ORCID: ORCID

  1. Wroclaw University of Science and Technology, Faculty of Information and Communication Technology, Wybrzeze Wyspiańskiego 27, 50-370 Wrocław, Poland
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Abstract

The paper presents the novel concept of the magnetoelectric sensor constructed using the amorphous glass ribbon. Its output characteristics (voltage pattern), conditions of work and experimental results are presented. The novel construction allows for minimizing the demagnetizing field in the core of the sensor and linearization of the characteristics between the magnetic field and obtained voltage. Conducted experiments were aimed at determining the sensor operation in the presence of the constant magnetic field (HDC). The main concern of the tests was to verify the linear dependency between the HDC value and the amplitude of the output voltage. Next, the computer model representing the sensor behavior in the constant magnetic field is described. The model implements the parameter identification task based on the regression algorithms. The presented work shows that the proposed device can be used to measure the weak magnetic field and the dependency between the output signal amplitudes and the constant component in the measured magnetic field is approximately linear. This enables measurements of even weak fields.
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Authors and Affiliations

Karol Kuczynski
1
ORCID: ORCID
Piotr Bilski
1
ORCID: ORCID
Adrian Bilski
2
ORCID: ORCID
Jerzy Szymanski
3
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Electronics and Information Technology, Institute of Radioelectronics and Multimedia Technology, Poland
  2. Warsaw University of Life Sciences, Poland
  3. Kazimierz Pulaski University of Technology and Humanities in Radom, Faculty of Transport, Electrical Engineering and Computer Science, Poland
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Abstract

This paper explains the rotation and displacement as well as the couple and force stress in material with unpaired electrons/nucleons subjected to a magnetic field. This phenomenon is described in terms of quantum mechanics for nanoparticle and quantum statistical mechanics for loose nanomaterial. Quantitative calculations are carried out based on experimental data collected under the magnetic field of an EPR spectrometer from a set of nanocrystallites of hydrated copper sulfate.
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Authors and Affiliations

Marek Sikoń
1
ORCID: ORCID
Ewa Bidzinska
2

  1. Cracow University of Technology, Kraków, Poland
  2. Jagiellonian University, Kraków, Poland
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Abstract

The application of 3D printers significantly improves the process of producing foundry patterns in comparison to traditional methods of their production. It should be noted that the quality of the surface texture of the foundry pattern is crucial because it affects the quality of the casting mold and eventually the finished casting. In most studies, the surface texture is examined by analyzing the 2D or 3D roughness parameters. This is a certain limitation because, in the case of 3D printing, the influence of technological parameters is more visible for irregularities of a longer range, such as surface waviness. In the paper, the influence of the 3D printing layer thickness on the formation of waviness of the surface of casting patterns was analyzed. Three 3D printers, differing in terms of printing technology and printing material, were tested: PJM (PolyJet Matrix), FDM (fused deposition modeling) and SLS (selective laser sintering). In addition, the surface waviness of patterns manufactured with traditional methods was analyzed. Surface waviness has been measured using the Form Talysurf PGI 1200 measuring system. Preliminary results of the research showed that the layer thickness significantly influences the values of waviness parameters of the surface in the casting patterns made with FDM, PJM and SLS additive technologies. The research results indicated that the smallest surface waviness as defined by parameters Wa, Wq and Wt was obtained for patterns printed using the PJM technology, while the highest was noted when using the FDM technology.
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Authors and Affiliations

Paweł Zmarzły
1
ORCID: ORCID
Damian Gogolewski
1
Tomasz Kozior
1

  1. Faculty of Mechatronics and Mechanical Engineering, Kielce University of Technology, Poland
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Abstract

Due to the organization of construction works, one of the most difficult situations is when a building is planned in a heritage or a densely built-up location. Fixing an existing situation manually takes a lot of time and effort and is usually not accurate. For example, it is not always possible to measure the exact spacing between buildings at different levels and to consider all outside elements of an existing building. Improper fixation of the existing situation causes mistakes and collisions in design and the use of inappropriate construction solutions. The development and progress in technologies such as BIM, laser scanning, and photogrammetry broaden the options for supporting the management of construction projects. It is important to have an effective fast collection and processing of useful information for management processes. The purpose of this paper is to analyze and present some aspects of photogrammetry to collect and process information about existing buildings. The methodology of the study is based on the comparison of two alternative approaches, namely photogrammetry and BIM modelling. Case studies present an analysis of the quantity take-offs for selected elements and parts of the buildings based on the two approaches. In this article, the specific use of photogrammetry shows that the error between the detailed BIM model and the photogrammetry model is only 1.02% and the accuracy is 98.98%. Moreover, physical capabilities do not always allow us to measure every desired element in reality. This is followed by a discussion on the usability of photogrammetry.
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Authors and Affiliations

Robertas Kontrimovicius
1
ORCID: ORCID
Michał Juszczyk
2
ORCID: ORCID
Agnieszka Leśniak
2
ORCID: ORCID
Leonas Ustinovichius
1
ORCID: ORCID
Czesław Miedziałowski
3
ORCID: ORCID

  1. Faculty of Civil Engineering, Vilnius Gediminas Technical University, Lithuania
  2. Faculty of Civil Engineering, Cracow University of Technology, Poland
  3. Faculty of Civil Engineering and Environmental Sciences, Bialystok University of Technology, Poland

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