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1
Content available Application of Recurrence Quantification Analysis in the Detection of Osteoarthritis of the Knee with the Use of Vibroarthrography
Machrowska Anna, Karpiński Robert, Maciejewski Marcin, Jonak Józef, Krakowski Przemysław, Syta Arkadiusz
Advances in Science and Technology. Research Journal
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2024
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Vol. 18, no 5
19--31
EN
Nowadays, the world is struggling with the problems of an aging society. With the increasing share of older people in the population, degenerative joint diseases are a growing problem. The result of progressive degenerative changes in joints is primarily the deterioration of the patients' quality of life and their gradual exclusion from activity and social life. The ability to effectively, non-invasively and quickly detect cases of chondromalacia of the knee joints is a challenge for modern medicine. The possibility of early detection of progressive degenerative changes allows for the appropriate selection of treatment protocols and significantly increases the chances of inhibiting the development of degenerative diseases of the musculoskeletal system. The article presents a non-invasive method for detecting degenerative changes in the knee joints based on recurrence analysis and classification using neural networks. The result of the analyzes was a classification accuracy of 91.07% in the case of MLP neural networks and 80.36% for RBF networks.
2
Content available remote A Numerical Study of the Influence of Cone Angle of the Breakout Anchor Head on the Crack Trajectory of the Medium
Karpiński Robert, Jonak Józef, Wójcik Andrzej, Jonak Kamil, Prostański Dariusz, Kaczyński Roman
Advances in Science and Technology. Research Journal
|
2024
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Vol. 18, no 5
EN
Anchors of various designs are crucial, especially in mining and underground construction, where they stabilise the excavation and prevent the movement of rocks. They make it possible to control the direction of cracking during explosions, limit the dispersion of rock material and minimise damage from vibrations. The use of anchors increases the safety and efficiency of work in difficult geological conditions. The authors propose the use of modified anchor construction for the detachment of rock lumps. The paper presents the results of a numerical analysis carried out using the finite element method (FEM) on the effect of the angle of the anchor conical head of a new breakout design on the formation of the detachment crack trajectory influencing the range and, consequently, the volume of detached rock output. The analysis was carried out with a view to explaining the mechanism of separation of lumps of rock by the anchor treated as a mining tool.
3
Content available Comparison of selected classification methods based on machine learning as a diagnostic tool for knee joint cartilage damage based on generated vibroacoustic processes
Karpiński Robert, Krakowski Przemysław, Jonak Józef, Machrowska Anna, Maciejewski Marcin
Applied Computer Science
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2023
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Vol. 19, no 4
136--150
EN
Osteoarthritis is one of the most common cause of disability among elderly. It can affect every joint in human body, however, it is most prevalent in hip, knee, and hand joints. Early diagnosis of cartilage lesions is essential for fast and accurate treatment, which can prolong joint function. Available diagnostic methods include conventional X-ray, ultrasound and magnetic resonance imaging. However, those diagnostic modalities are not suitable for screening purposes. Vibroarthrography is proposed in literature as a screening method for cartilage lesions. However, exact method of signal acquisition as well as classification method is still not well established in literature. In this study, 84 patients were assessed, of whom 40 were in the control group and 44 in the study group. Cartilage status in the study group was evaluated during surgical treatment. Multilayer perceptron - MLP, radial basis function - RBF, support vector method - SVM and naive classifier – NBC were introduced in this study as classification protocols. Highest accuracy (0.893) was found when MLP was introduced, also RBF classification showed high sensitivity (0.822) and specificity (0.821). On the other hand, NBC showed lowest diagnostic accuracy reaching 0.702. In conclusion vibroarthrography presents a promising diagnostic modality for cartilage evaluation in clinical setting with the use of MLP and RBF classification methods.
4
Content available Influence of Anchor Depth and Friction Coefficient Between Anchor and Rock on the Trajectory of Rock Masses Detachment
Jonak Józef, Karpiński Robert, Wójcik Andrzej
Advances in Science and Technology. Research Journal
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2023
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Vol. 17, no 4
290--298
EN
This work presents the results of a FEA (Finite Element Analysis) concerning the propagation of the fracture tra- jectory during the detachment of rock masses. The analysis considers mechanical anchoring parameters, including the depth of anchoring and the friction between the anchor head and the brittle material. The analysis involved varying the effective anchorage depth hef = 50, 100, and 150 mm, along with considering different coefficients of friction (μ) for the anchor head against the rock, including 0.15, 0.3, and 0.45. The results indicated that within the chosen range of anchorage depths, the extent of damage increases with the depth of anchor embedment. However, the depth of anchoring, considering the studied range of this parameter and the assumed mechanical properties of the rock, did not have a significant effect on the value of the angle cone (α0) during the initial phase of the medium’s destruction. For the friction coefficient μ = 0.15, there is a clear deep penetration into the fracture at its initial stage of development (at the initial angle of α0 = -20°), promoting further spread of the fracture on the free surface. For larger values of the friction coefficient (μ = 0.3 and 0.45) – the trend is less pronounced (α0 = -2°÷-8°) resulting in a decrease in the crack range.
5
Koncepcja zawieszanie koła rowerowego z odzyskiem energii z drgań
Jonak Józef, Karpiński Robert, Brodacz Bartłomiej
Prace Naukowe Politechniki Warszawskiej. Elektronika
|
2022
|
z. 197, t. 2
307-315
PL
W artykule przedstawiono koncepcje zawieszenia koła rowerowego pozwalającego na odzysk energii z drgań mechatronicznych generowanych podczas jazdy rowerem po nierównościach drogi. Zaproponowano generator elektromagnetyczny zabudowy w zawieszeniu koła rowerowego (w tak zwanym widelcu), symetrycznie jeden zestaw po każdej stronie koła.
EN
The paper presents a concept of a bicycle wheel suspension slowing recovery of energy from mechanical vibrations generated while cycling on uneven roads. An electromagnetic generator installed in the suspension of a bicycle wheel, symmetrically one set on each side of the wheel was proposed.
6
Content available Knee joint osteoarthritis diagnosis based on selected acoustic signal discriminants using machine learning
Karpiński Robert
Applied Computer Science
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2022
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Vol. 18, no 2
71--85
EN
This paper presents the results of a preliminary study on simplified diagnosis of osteo-arthritis of the knee joint based on generated vibroacoustic processes. The analysis was based on acoustic signals recorded in a group of 50 people, half of whom were healthy, and the other half – people with previously confirmed degenerative changes. Selected discriminants of the signals were determined and statistical analysis was performed to allow selection of optimal discriminants used at a later stage as input to the classifier. The best results of classification using artificial neural networks (ANN) of RBF (Radial Basis Function) and MLP (Multilevel Perceptron) types are presented. For the problem involving the classification of cases into one of two groups HC (Healthy Control) and OA (Osteoarthritis) an accuracy of 0.9 was obtained, with a sensitivity of 0.885 and a specificity of 0.917. It is shown that vibroacoustic diagnostics has great potential in the non-invasive assessment of damage to joint structures of the knee.
7
Content available The Effect of Undercut Anchor Diameter on the Rock Failure Cone Area in Pullout Tests
Jonak Józef, Karpiński Robert, Wójcik Andrzej, Siegmund Michał
Advances in Science and Technology. Research Journal
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2022
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Vol. 16, no 5
261–270
EN
The numerical analysis was conducted using the FEM ABAQUS software to establish the impact of various undercut anchor diameters on the rock breakout cone formation. The central focus of the investigations was on the rock breakout prism, which tends to be approximated to a cone or a quadrilateral pyramid, including its characteristic parameter, the angle of failure cone . Assuming that the embedment depth and the undercut anchor head angle were constant for the considered range of anchor head diameters, it remains unclear, however, precisely how the anchor head diameter affects the value of the failure cone angle, and thus the surface area of the full breakout prism. This conclusion stands in confirmation of our former considerations regarding the impact of the anchor head angle on the size of the breakout surface. Furthermore, it is supported by the results obtained from the mechanical model simulation of the anchor-rock system, where the anchor head angle and the effective embedment depth were determined as significant factors affecting the assumed rock breakout failure. The underlying aspect of the reported investigation was to evaluate the effectiveness of the non-conventional rock breakout technology performed with an undercut anchor, whose primary factors were both the pullout force and the assumed volume of the rock cone.
8
Content available Experimental Verification of Standard Recommendations for Estimating the Load-carrying Capacity of Undercut Anchors in Rock Material
Jonak Józef, Karpiński Robert, Siegmund Michał, Machrowska Anna, Prostański Dariusz
Advances in Science and Technology. Research Journal
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2021
|
Vol. 15, no 1
230--244
EN
The recommendations put forward in the International Standards for anchorage in concrete concerning the assessment of the load-carrying capacity of anchors (the pull-out force) embedded in natural rock material were verified. Regarding the predicted extent of surface failure we have shown, in earlier studies, substantial discrepancies between the strength test results for anchorages in the rock mass and the established standard recommendations for anchorages in concrete. As regards the industrial practice and the goals of the reported project, simplified calculation procedures that will facilitate the selection of optimal configurations for the layout of anchor holes, while being computationally effective and applicable under the industry-specific conditions are sought.
9
Content available Numerical prediction of component-ratio-dependent compressive strength of bone cement
Machrowska Anna, Karpiński Robert, Jonak Józef, Szabelski Jakub, Krakowski Przemysław
Applied Computer Science
|
2020
|
Vol. 16, no 3
87--101
EN
Changes in the compression strength of the PMMA bone cement with a variable powder/liquid component mix ratio were investigated. The strength test data served to develop basic mathematical models and an artificial neural network was employed for strength predictions. The empirical and numerical results were compared to determine modelling errors and assess the effectiveness of the proposed methods and models. The advantages and disadvantages of mathematical modelling are discussed.
10
Content available Electrocardiogram generation software for testing of parameter extraction algorithms
Maciejewski Marcin, Maciejewska Barbara, Karpiński Robert, Krakowski Przemysław
Applied Computer Science
|
2020
|
Vol. 16, no 4
37--47
EN
Fast and automated ECG diagnosis is of great benefit for treatment of cardi-ovascular and other conditions. The algorithms used to extract parameters need to be precise, robust and efficient. Appropriate training and testing methods for such algorithms need to be implemented for optimal results. This paper presents a software solution for computer ECG generation and a simplified concept of testing process. All the parameters of the resulting generated signal can be tweaked and set properly. Such software can also be beneficial for training and educational use.
11
Content available Usefulness of rapid prototyping in planning complex trauma surgeries
Krakowski Przemysław, Jonak Józef, Karpiński Robert, Jaworski Łukasz
Applied Computer Science
|
2019
|
Vol. 15, no 3
65--72
EN
Orthopaedic trauma surgery is a complex surgical speciality in which anatomy, physiology and physics are mixed. Proper diagnosing and based on that planning and performing surgery is of crucial matter. This article presents usefulness of 3D reconstruction in diagnostics and surgical planning. It focuses on utility of computed tomography reconstruction in trauma surgery. Moreover, two cases in which this technique was used is described. Complex 3D reconstruction proved its usefulness and in future it may become a modality of choice for planning complex trauma procedures in which standard implants and approaches are insufficient.
12
Content available Diagnostic factors for opened and closed kinematic chain of vibroarthrography signals
Machrowska Anna, Karpiński Robert, Krakowski Przemysław, Jonak Józef
Applied Computer Science
|
2019
|
Vol. 15, no 3
34--44
EN
The paper presents results of preliminary research of vibroarthrography signals recorded from one healthy volunteer. The tests were carried out for the open and closed kinematic chain in the range of motion 90° – 0° – 90°. Analysis included initial signal filtration using the EMD algorithm. The aim was to investigate the occurrence of differences in the values of selected energy and statistical parameters for the cases studied.
13
Content available Application of acoustic signal processing methods in detecting differences between open and closed kinematic chain movement for the knee joint
Karpiński Robert, Machrowska Anna, Maciejewski Marcin
Applied Computer Science
|
2019
|
Vol. 15, no 1
36--48
EN
The paper presents results of preliminary research of analysis of signals recorded for open and closed kinematic chain in one volunteer with chondromalacia in both knees. The preliminary research was conducted in order to establish the accuracy of the proposed method and will be used for formulating further research areas. The aim of the paper is to show how FFT, recurrence plots and recurrence quantification analysis (RQA) can help in bioacoustic signals analysis.
14
Content available Applications of modern imaging technology in orthopaedic trauma surgery
Krakowski Przemysław, Karpiński Robert, Maciejewski Marcin
Applied Computer Science
|
2018
|
Vol. 14, no 3
96--106
EN
Orthopaedic trauma surgery is a complex surgical speciality in which anatomy, physiology and physics are mixed. Proper diagnosing and based on that planning and performing surgery is of crucial matter. This article briefly summarizes available radiological modalities used for diagnostics and for surgical planning. It focuses on utility of rapid prototyping process in trauma surgery. Moreover, a case study in which this technique was used is described. Rapid prototyping proved its usefulness and in future it may become a modality of choice for planning complex trauma procedures.
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