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Automated Multi-Dimensional Corrosion Growth Modeling Based on In-Line Inspections

Péter Földesi Mohamad Shatnawi

Publication Name: IEEE Access

Publication Date: 2026-01-01

Volume: 14

Issue: Unknown

Page Range: 57997-58015

Description:

Corrosion is responsible for up to one-third of reported pipeline incidents. Given the extensive length and limited accessibility of pipelines, operators rely on in-line inspections (ILIs) to detect and quantify corrosion defects. Although modern ILI tools provide detailed geometric descriptions of corrosion behavior, translating successive inspections into reliable growth models remains challenging. Measurement uncertainty, defect coalescence, and the joint evolution of length, width, and depth complicate learning consistent growth patterns. This study proposes a unified framework for automated corrosion growth modeling that integrates feature matching, feature engineering, and data-driven prediction into a single workflow. The framework targets defect-level modeling by jointly learning multi-dimensional corrosion growth of length, width, and depth, and by reducing correspondence-induced artifacts arising from defect coalescence and measurement uncertainty. The effectiveness of the framework was evaluated using three consecutive ultrasonic testing inspections of an API 5L X52 offshore water-injection pipeline segment. Extreme Gradient Boosting (XGBoost), a feed-forward neural network, Random Forest, and linear regression were used to assess the stability of the proposed geometric representation across learning paradigms. Integrity-oriented evaluation using Estimated Repair Factor (ERF) indicates that integrity-relevant trends are preserved. Furthermore, geometry-oriented evaluation using agreement and error analyses indicates strong performance for axial length and circumferential width, with modestly reduced performance for depth. Overall, the results suggest that the proposed framework provides a practical basis for defect-level automated corrosion growth modeling.

Open Access: Yes

DOI: 10.1109/ACCESS.2026.3683313

MANAGING SOCIAL PROTECTION FOR EX-COMBATANTS: EVALUATING EFFECTIVENESS THROUGH КРІ METHODOLOGY

Yuriy Bilan Halyna Mishchuk Natalia Samoliuk Iryna Roshchyk

Publication Name: Polish Journal of Management Studies

Publication Date: 2025-06-25

Volume: 31

Issue: 1

Page Range: 248-263

Description:

The management of the ex-combatants’ social protection is analysed using the KPI methodology. For this analysis, five blocks of indicators are adapted: “input” – funding allocated to ex-combatants’ social protection; “output” – ex-combatants’ participation in social programs; “activity” – funding per recipient and final performance of social protection; “mechanism” – administrative efforts required to achieve the intended outcomes; “control” – effectiveness of ex-combatants’ social protection compared to other population groups. The methodology has been tested in Ukraine using a system of 28 indicators available in 2020-2023. The lowest efficiency is typical for input indicators, mainly support programs funding (0.153 in 2022), the highest values were observed for activities indicators (ranging from 0,609 to 0.871). However, the essential distance from maximum level of 1.0 is obvious for all indicators. This approach allows for identifying existing gaps and opportunities to improve public management of ex-combatants’ social protection.

Open Access: Yes

DOI: 10.17512/pjms.2025.31.1.14

A concept reduction approach for fuzzy cognitive map models in decision making and management

Miklós F. Hatwágner Adrienn Buruzs Elpiniki I. Papageorgiou László T. Kóczy

Publication Name: Neurocomputing

Publication Date: 2017-04-05

Volume: 232

Issue: Unknown

Page Range: 16-33

Description:

Policy making, strategic planning and management in general are complex decision making tasks, where the formulation of a quantitative mathematical model may be difficult or impossible due to lack of numerical data and dependence on imprecise verbal expressions. For such systems, knowledge representation graphs and cognitive maps are most familiar and often used for modelling complexity and aiding decision making. Fuzzy Cognitive Maps (FCM), as graph-based cognitive models, have been successfully used for knowledge representation and reasoning. In modelling complex systems usually a large number of concepts need to be considered. However, it is often difficult in real applications to find the appropriate number of concepts. Using only a few concepts is not enough to represent the modelled system with the required precision, and increasing the number of concepts increases the complexity of the model quadratically; it is burdensome to work with for the experts. The contribution of this paper is two-fold: (i) to propose a new concept reduction approach for FCM and (ii) to apply it on developing less complex FCM for management and decision making. The behaviour of reduced models is analysed through a number of scenarios with respect to the original complex system. The main idea of the reduction is a clustering based on fuzzy tolerance relations. The new approach is focused on reducing complexity in the modelling process, which provides a more transparent and easy to use model for policy makers. The applicability of the proposed method is demonstrated via literature examples and a solid waste management case study that initiated this research. The results clearly show the advantageous characteristics of the proposed concept reduction method for FCM and its aid in policy making.

Open Access: Yes

DOI: 10.1016/j.neucom.2016.11.060

Musculoskeletal modelling sequentially integrated with stress simulation reveals asymmetrical knee loading and ligament stress during long-distance running

Yaodong Gu Julien S. Baker Gusztáv Fekete Qichang Mei Liangliang Xiang Zixiang Gao Hanhui Jiang

Publication Name: BMC Sports Science Medicine and Rehabilitation

Publication Date: 2025-12-01

Volume: 17

Issue: 1

Page Range: Unknown

Description:

Background: Understanding the internal load characteristics of the knee joint is essential for investigating unilateral knee injuries associated with running. This study examined the differences in the location and magnitude of von Mises stress in the internal structures of bilateral knee joints during the stance phase of gait following 10 km running at submaximal speeds. Methods: A healthy male recreational runner participated in this study. We employed a synergistic approach, integrating subject-specific knee joint angles, reaction forces, and moments derived from musculoskeletal modeling to inform and drive the finite element (FE) modeling of running. This methodology ensured a detailed and accurate representation of knee joint mechanics. The peak stresses of the bilateral knee menisci, tibial cartilage, and five main ligaments were quantified using a FE model during the stance phase. Results: The meniscus, tibial cartilage, anterior (ACL), posterior cruciate ligament (PCL), medial (MCL), lateral collateral ligament (LCL) and experienced larger loads in the non-dominant limb across most phases of stance. Additionally, fatigue elevated the peak loading on the non-dominant limb’s ACL, PCL, and LCL during the gait stance phase but diminished the load on these ligaments in the dominant knee joint. For Patellar ligament (PL), the non-dominant side showed maximal stress at initial contact, while the dominant side dominated during the remaining stance phases. Conclusions: This proof-of-concept substantially enhances our understanding of the impact of running-induced fatigue on bilateral knee loading. It provides a detailed analysis of factors leading to unilateral knee overload during extended running. These insights are essential in formulating targeted strategies to reduce injury risks.

Open Access: Yes

DOI: 10.1186/s13102-025-01372-3

Overview of Hungarian operations research based on the VOCAL 2022 conference

Botond Bertok Marianna E.-Nagy Péter Biró

Publication Name: Central European Journal of Operations Research

Publication Date: 2024-12-01

Volume: 32

Issue: 4

Page Range: 897-902

Description:

The latest results of the Hungarian operations research community is reviewed based on the presentations given at the VOCAL 2022 conference. International collaborations and the continuation of research published at previous conferences of the series are also summarized.

Open Access: Yes

DOI: 10.1007/s10100-024-00930-3

Dynamics of Classical Fuzzy Cognitive Maps

Istvan A. Harmati

Publication Name: Studies in Fuzziness and Soft Computing

Publication Date: 2024-01-01

Volume: 427

Issue: Unknown

Page Range: 105-119

Description:

In Fuzzy Cognitive Map based modelling, the final conclusion is based on the assumption that the system reaches an equilibrium point (fixed point) after a certain number of iteration. It is not straightforward that this leads to a fixed point, since the iteration may show various dynamical behaviours: multiple fixed points, limit cycle and unpredictable patterns may also occur. In this chapter, a gentle insight into the dynamics of FCMs’ is provided based on solid mathematical tools. We prove sufficient conditions for the existence and uniqueness of fixed points for sigmoid, hyperbolic tangent and rescaled sigmoid FCMs, which are also necessary in the case of the latter two. Additionally, symmetrical properties of fixed points and basins of attraction of hyperbolic tangent and rescaled sigmoid FCMs are also introduced with mathematical proof.

Open Access: Yes

DOI: 10.1007/978-3-031-37959-8_9

Non-Square Inverse Function Jacobians in Controlled Multibody Systems: Numerical and Application Examples

Ambrus Zelei

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 112-120

Description:

When control algorithms of robots are constructed, the joint coordinates and the coordinates describing the dynamics might be different and the transformation between them might be necessary in both directions. The back-and-forth transformations are related to the inverse function theorem, which is well understood for single and multivariable continuous functions: the conditions are described under which the inverse function exist, furthermore the method is provided to calculate the Jacobian of the inverse function. A generalization of the theorem is necessary, when there are fewer dependent variables than independent ones, and furthermore there are constraint equations for the independent variables. It is exactly the case for model-based inverse dynamics control of multibody systems, when the dynamic model is given in terms of a redundant coordinate set, but the controller is formulated for minimum set coordinates. The widely used so-called natural coordinates are a typical redundant set. Minimum-coordinates come in the picture when the control is formulated for the joint coordinates. Clearly, when the natural coordinates are transformed to joint coordinates, there is information loss. The inverse transformation is however still possible, since there are constraint equations for the redundant set. This paper demonstrates a method for the transformation from minimum to redundant coordinates and vice versa with the help of the generalized inverse of the non-square constraint Jacobian and the projection matrices related to the constrained and admissible subspace of the redundant set. An illustrative numerical example and a robotic application demonstrate the theory. The results are relevant in the model-based control of complex-structure parallel kinematic chain robots.

Open Access: Yes

DOI: 10.3233/ATDE240534

Simulation and measurement of magnetic based nondestructive tester

Miklós Kuczmann Gergely Kovács

Publication Name: Przeglad Elektrotechniczny

Publication Date: 2009-12-01

Volume: 85

Issue: 12

Page Range: 76-79

Description:

The paper presents the analysis of a nondestructive testing equipment under investigation. There are three main parts of the research as well as this paper. The first part shows the present state of the developed nondestructive tester based on the Magnetic Flux Leakage (MFL) method, the second part reviews the simulation and the results, which have been made with the principle of the Finite Element method (FEM). The last part presents the measurement results, which have been performed with the nondestructive tester. In this paper the simulation results with the measurement results have been compared.

Open Access: Yes

DOI: DOI not available

Comparison of the effects and efficiency of vertical and side tamping methods for ballasted railway tracks

Szabolcs Fischer Ulf Gerber Vitalii Kovalchuk Mykola Sysyn Michał Przybyłowicz

Publication Name: Construction and Building Materials

Publication Date: 2022-01-03

Volume: 314

Issue: Unknown

Page Range: Unknown

Description:

The relatively high maintenance costs of the ballast track are related to the short lifecycle of the ballast layer. The current vertical ballast tamping technology (e.g., Plasser & Theurer, Matisa, etc.) causes high ballast destruction and is neither applicable for unconventional sleepers’ designs nor slab tracks. The side tamping method presents an alternative, ballast saving, and sleeper form independent ballast tamping technology. This paper compares the ballast layer compaction and its resistance to permanent settlements accumulation after the vertical and the side tamping methodologies. Scaled models of ballast layer and tamping units and scaled simulation with discrete element method (DEM) were applied for the comparison. In the laboratory tests, the ballast compaction along the sleeper was estimated using the measurements of elastic wave propagation. The settlements resistance for both tamping methods was estimated under the vibration loading. The tests’ results show 5–7% higher compactness of the ballast layer under the sleeper ends for the side tamping method. The settlement intensity of the ballast layer after the vertical tamping is higher than for the side tamping method. In discrete element modeling, the performed laboratory tests were simulated. The compactness of the ballast bed, as well as the residual stresses, were determined in MATLAB. The side tamping technology provided five times higher residual stresses in the ballast layer below the sleeper than in the case of vertical tamping, which can be explained by the more stable and dense layer resulting from the side tamping ensures higher interlocking between the grains. The simulation of the wave propagation shows an influence of the residual stresses on the wave propagation velocities. The simulated wave propagation velocity was more than two times higher for the side tamping than for the vertical one.

Open Access: Yes

DOI: 10.1016/j.conbuildmat.2021.125708