[go: up one dir, main page]
More Web Proxy on the site http://driver.im/
You seem to have javascript disabled. Please note that many of the page functionalities won't work as expected without javascript enabled.
 
 
Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Article Types

Countries / Regions

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Search Results (1,098)

Search Parameters:
Keywords = machine tool monitoring

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
54 pages, 7881 KiB  
Review
Spectroscopy-Based Methods and Supervised Machine Learning Applications for Milk Chemical Analysis in Dairy Ruminants
by Aikaterini-Artemis Agiomavriti, Maria P. Nikolopoulou, Thomas Bartzanas, Nikos Chorianopoulos, Konstantinos Demestichas and Athanasios I. Gelasakis
Chemosensors 2024, 12(12), 263; https://doi.org/10.3390/chemosensors12120263 - 13 Dec 2024
Abstract
Milk analysis is critical to determine its intrinsic quality, as well as its nutritional and economic value. Currently, the advancements and utilization of spectroscopy-based techniques combined with machine learning algorithms have made the development of analytical tools and real-time monitoring and prediction systems [...] Read more.
Milk analysis is critical to determine its intrinsic quality, as well as its nutritional and economic value. Currently, the advancements and utilization of spectroscopy-based techniques combined with machine learning algorithms have made the development of analytical tools and real-time monitoring and prediction systems in the dairy ruminant sector feasible. The objectives of the current review were (i) to describe the most widely applied spectroscopy-based and supervised machine learning methods utilized for the evaluation of milk components, origin, technological properties, adulterants, and drug residues, (ii) to present and compare the performance and adaptability of these methods and their most efficient combinations, providing insights into the strengths, weaknesses, opportunities, and challenges of the most promising ones regarding the capacity to be applied in milk quality monitoring systems both at the point-of-care and beyond, and (iii) to discuss their applicability and future perspectives for the integration of these methods in milk data analysis and decision support systems across the milk value-chain. Full article
Show Figures

Figure 1

Figure 1
<p>The electromagnetic spectrum and wavelength ranges of electromagnetic radiation.</p>
Full article ">Figure 2
<p>Example of light’s interaction with matter [<a href="#B14-chemosensors-12-00263" class="html-bibr">14</a>] (modified).</p>
Full article ">Figure 3
<p>Scatter light effects are generated by fat and protein particles in milk. The incident wavelength is smaller than the diameter of the particles, resulting in Mie scattering, which is demonstrated in the zoomed view [<a href="#B17-chemosensors-12-00263" class="html-bibr">17</a>].</p>
Full article ">Figure 4
<p>Different colors refract at different angles in a dispersive prism due to material dispersion; a wavelength-dependent refractive index divides white light into a spectrum [<a href="#B18-chemosensors-12-00263" class="html-bibr">18</a>].</p>
Full article ">Figure 5
<p>Optical sensors classification from the International Union of Pure and Applied Chemistry (IUPAC) [<a href="#B21-chemosensors-12-00263" class="html-bibr">21</a>].</p>
Full article ">Figure 6
<p>Milk application and spectroscopy methods [<a href="#B22-chemosensors-12-00263" class="html-bibr">22</a>].</p>
Full article ">Figure 7
<p>Illustration of the spectroscopy procedure.</p>
Full article ">Figure 8
<p>(<b>a</b>) Continuous spectrum: contains all wavelengths emitted by a light source, (<b>b</b>) Absorption spectrum: black lines where the electrons have absorbed the light photons, (<b>c</b>) Emission spectrum: color lines where photons have been released from the electrons when they fall to a lower energy level. The different colors correspond to specific wavelengths, representing distinct photon energies released when electrons transition to a lower energy state. These colors depend on the material and the energy transitions within the atoms or molecules [<a href="#B33-chemosensors-12-00263" class="html-bibr">33</a>].</p>
Full article ">Figure 9
<p>Near-infrared spectra of milk samples, each color represents a distinct sample. [<a href="#B34-chemosensors-12-00263" class="html-bibr">34</a>].</p>
Full article ">Figure 10
<p>Fourier transform infrared spectra of sheep (blue line), goat (green line), and cow milk (orange line) samples [<a href="#B35-chemosensors-12-00263" class="html-bibr">35</a>].</p>
Full article ">Figure 11
<p>Laser-induced breakdown spectroscopy spectra from liquid milk samples, illustrating the unique spectral lines for major elements (Mg, Ca, Na, etc.) [<a href="#B36-chemosensors-12-00263" class="html-bibr">36</a>].</p>
Full article ">Figure 12
<p>Near-infrared spectroscopy analytical methods and their integration into production processes.</p>
Full article ">Figure 13
<p>Supervised ML process of data.</p>
Full article ">Figure 14
<p>Supervised ML methods applied in dairy ruminants and milk analysis research [<a href="#B113-chemosensors-12-00263" class="html-bibr">113</a>,<a href="#B114-chemosensors-12-00263" class="html-bibr">114</a>,<a href="#B115-chemosensors-12-00263" class="html-bibr">115</a>].</p>
Full article ">Figure 15
<p>Example representation of a neural network model.</p>
Full article ">Figure 16
<p>Overview of the application of spectral technologies and machine learning for milk analysis.</p>
Full article ">
17 pages, 7893 KiB  
Article
Modern SCADA for CSP Systems Based on OPC UA, Wi-Fi Mesh Networks, and Open-Source Software
by Jose Antonio Carballo, Javier Bonilla, Jesús Fernández-Reche, Antonio Luis Avila-Marin and Blas Díaz
Energies 2024, 17(24), 6284; https://doi.org/10.3390/en17246284 - 13 Dec 2024
Viewed by 179
Abstract
This study presents a methodology for the development of modern Supervisory Control and Data Acquisition (SCADA) systems aimed at improving the operation and management of concentrated solar power (CSP) plants, leveraging the tools provided by industrial digitization. This approach is exemplified by its [...] Read more.
This study presents a methodology for the development of modern Supervisory Control and Data Acquisition (SCADA) systems aimed at improving the operation and management of concentrated solar power (CSP) plants, leveraging the tools provided by industrial digitization. This approach is exemplified by its application to the CESA-I central tower heliostat field at the Plataforma Solar de Almería (PSA), one of the oldest CSP facilities in the world. The goal was to upgrade the control and monitoring capabilities of the heliostat field by integrating modern technologies such as OPC (Open Platform Communications)) Unified Architecture (UA), a Wi-Fi mesh communication network, and a custom Python-based gateway for interfacing with legacy MODBUS systems. Performance tests demonstrated stable, scalable communication, efficient real-time control, and seamless integration of new developments (smart heliostat) into the existing infrastructure. The SCADA system also introduced a user-friendly Python-based interface developed with PySide6, significantly enhancing operational efficiency and reducing task complexity for system operators. The results show that this low-cost methodology based on open-source software provides a flexible and robust SCADA architecture, suitable for future CSP applications, with potential for further optimization through the incorporation of artificial intelligence (AI) and machine learning. Full article
(This article belongs to the Special Issue Advances in Solar Thermal Energy Harvesting, Storage and Conversion)
Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
<p>CESA-I system captions.</p>
Full article ">Figure 2
<p>SCADA CESA-I architecture.</p>
Full article ">Figure 3
<p>CESA-Modbus library polling function.</p>
Full article ">Figure 4
<p>SCADA main window (1—heliostat field, 2—information, 3—control, 4—logging and console).</p>
Full article ">Figure 5
<p>Meteorological data subsection.</p>
Full article ">Figure 6
<p>Central subsection of the main area.</p>
Full article ">Figure 7
<p>Legend subsection of the main area.</p>
Full article ">Figure 8
<p>Information area.</p>
Full article ">Figure 9
<p>Control area.</p>
Full article ">Figure 10
<p>Login area.</p>
Full article ">Figure 11
<p>Login area.</p>
Full article ">Figure 12
<p>Heliostat window.</p>
Full article ">Figure 13
<p>Smart heliostat control window.</p>
Full article ">
13 pages, 1062 KiB  
Article
Real-Time Computing Strategies for Automatic Detection of EEG Seizures in ICU
by Laura López-Viñas, Jose L. Ayala and Francisco Javier Pardo Moreno
Appl. Sci. 2024, 14(24), 11616; https://doi.org/10.3390/app142411616 - 12 Dec 2024
Viewed by 251
Abstract
Developing interfaces for seizure diagnosis, often challenging to detect visually, is rising. However, their effectiveness is constrained by the need for diverse and extensive databases. This study aimed to create a seizure detection methodology incorporating detailed information from each EEG channel and accounts [...] Read more.
Developing interfaces for seizure diagnosis, often challenging to detect visually, is rising. However, their effectiveness is constrained by the need for diverse and extensive databases. This study aimed to create a seizure detection methodology incorporating detailed information from each EEG channel and accounts for frequency band variations linked to the primary brain pathology leading to ICU admission, enhancing our ability to identify epilepsy onset. This study involved 460 video-electroencephalography recordings from 71 patients under monitoring. We applied signal preprocessing and conducted a numerical quantitative analysis in the frequency domain. Various machine learning algorithms were assessed for their efficacy. The k-nearest neighbours (KNN) model was the most effective in our overall sample, achieving an average F1 score of 0.76. For specific subgroups, different models showed superior performance: Decision Tree for ‘Epilepsy’ (average F1 score of 0.80) and ‘Craniencephalic Trauma’ (average F1 score of 0.84), Random Forest for ‘Cardiorespiratory Arrest’ (average F1 score of 0.89) and ‘Brain Haemorrhage’ (average F1 score of 0.84). In the categorisation of seizure types, Linear Discriminant Analysis was most effective for focal seizures (average F1 score of 0.87), KNN for generalised (average F1 score of 0.84) and convulsive seizures (average F1 score of 0.88), and logistic regression for non-convulsive seizures (average F1 score of 0.83). Our study demonstrates the potential of using classifier models based on quantified EEG data for diagnosing seizures in ICU patients. The performance of these models varies significantly depending on the underlying cause of the seizure, highlighting the importance of tailored approaches. The automation of these diagnostic tools could facilitate early seizure detection. Full article
Show Figures

Figure 1

Figure 1
<p>Cohort distribution of recruited sample size.</p>
Full article ">Figure 2
<p>Noise reduction in mathematical transforms. On the left, we show the graphics corresponding to the mathematical transform Fourier applied to raw data. On the right, after using a biological 1.5 transform to the signal from the upper left, the power of the spectrum from the four main frequency bands can be shown, with an evident change related to a seizure. After applying a Wavelet transform, Daubechies 4, the spectrum potency for each frequency band can be demonstrated at a moment in which a seizure is happening.</p>
Full article ">Figure 3
<p>(<b>A</b>) Confusion matrix in the analysis of the performance in seizure detection between patients suffering from epilepsy and patients with a normal recording. It shows a sensitivity of 75% and a specificity of 78.8%. (<b>B</b>) Confusion matrix in the analysis of the performance in seizure detection between patients suffering from seizures who had epilepsy and patients with a normal recording. It shows a sensitivity of 85.7% and a specificity of 80%. (<b>C</b>) Confusion matrix in the analysis of the performance in seizure detection between patients suffering from seizures and patients with a normal recording, both from the subgroup Cranioencephalic Trauma. It shows a sensitivity of 100% and a specificity of 88.9%. (<b>D</b>) Confusion matrix in the analysis of the performance in seizure detection between patients suffering from seizures and patients with a normal recording, both from the subgroup Cardiorespiratory Arrest. It shows a sensitivity of 89.5% and a specificity of 100%. (<b>E</b>) Confusion matrix in the analysis of the performance in seizure detection between patients suffering from seizures and patients with a normal recording, both from the subgroup Brain haemorrhage. It shows a sensitivity of 100% and a specificity of 76.5%. (<b>F</b>) Confusion matrix in the analysis of the performance in seizure detection between patients suffering from focal seizures and patients with a normal recording. It shows a sensitivity of 100% and a specificity of 85.3%. (<b>G</b>) Confusion matrix in the analysis of the performance in seizure detection between patients suffering from generalised seizures and patients with a normal recording. It shows a sensitivity of 93.7% and a specificity of 100%. (<b>H</b>) Confusion matrix in the analysis of the performance in seizure detection between patients suffering from convulsive seizures and patients with a normal recording. It shows a sensitivity of 90.7% and a specificity of 100%. (<b>I</b>) Confusion matrix in the analysis of the performance in seizure detection between patients suffering from non-convulsive seizures and patients with a normal recording. It shows a sensitivity of 81.5% and a specificity of 100%.</p>
Full article ">
19 pages, 15445 KiB  
Article
The Use of Explainable Machine Learning for the Prediction of the Quality of Bulk-Tank Milk in Sheep and Goat Farms
by Daphne T. Lianou, Yiannis Kiouvrekis, Charalambia K. Michael, Natalia G. C. Vasileiou, Ioannis Psomadakis, Antonis P. Politis, Angeliki I. Katsafadou, Eleni I. Katsarou, Maria V. Bourganou, Dimitra V. Liagka, Dimitrios C. Chatzopoulos, Nikolaos M. Solomakos and George C. Fthenakis
Foods 2024, 13(24), 4015; https://doi.org/10.3390/foods13244015 - 12 Dec 2024
Viewed by 401
Abstract
The specific objective of the present study was to develop computational models, by means of which predictions could be performed regarding the quality of the bulk-tank milk in dairy sheep and goat farms. Our hypothesis was that use of specific variables related to [...] Read more.
The specific objective of the present study was to develop computational models, by means of which predictions could be performed regarding the quality of the bulk-tank milk in dairy sheep and goat farms. Our hypothesis was that use of specific variables related to the health management applied in the farm can facilitate the development of predictions regarding values related to milk quality, specifically for fat content, protein content, fat and protein content combined, somatic cell counts, and total bacterial counts. Bulk-tank milk from 325 sheep and 119 goat farms was collected and evaluated by established techniques for analysis of fat and protein content, for somatic cell counting, and for total bacterial counting. Subsequently, computational models were constructed for the prediction of five target values: (a) fat content, (b) protein content, (c) fat and protein, (d) somatic cell counts, and (e) total bacterial counts, through the use of 21 independent variables related to factors prevalent in the farm. Five machine learning tools were employed: decision trees (18 different models evaluated), random forests (16 models), XGBoost (240 models), k-nearest neighbours (72 models), and neural networks (576 models) (in total, 9220 evaluations were performed). Tools found with the lowest mean absolute percentage error (MAPE) between the five tools used to test predictions for each target value were selected. In sheep farms, for the prediction of protein content, k-nearest neighbours was selected (MAPE: 3.95%); for the prediction of fat and protein content combined, neural networks was selected (6.00%); and for the prediction of somatic cell counts, random forests and k-nearest neighbours were selected (6.55%); no tool provided useful predictions for fat content and for total bacterial counts. In goat farms, for the prediction of protein content, k-nearest neighbours was selected (MAPE: 6.17%); for the prediction of somatic cell counts, random forests and k-nearest neighbours were selected (4.93% and 5.00%); and for the prediction of total bacterial counts, neural networks was selected (8.33%); no tool provided useful prediction models for fat content and for fat and protein content combined. The results of the study will be of interest to farmers, as well as to professionals; the findings will also be useful to dairy processing factories. That way, it will be possible to obtain a distance-aware, rapid, quantitative estimation of the milk output from sheep and goat farms with sufficient data attributes. It will thus become easier to monitor and improve milk quality at the farm level as part of the dairy production chain. Moreover, the findings can support the setup of relevant and appropriate measures and interventions in dairy sheep and goat farms. Full article
(This article belongs to the Section Dairy)
Show Figures

Figure 1

Figure 1
<p>Locations of sheep (<b>left</b> map) and goat (<b>right</b> map) farms throughout Greece, which were visited for bulk-tank milk sampling.</p>
Full article ">Figure 2
<p>A flow diagram that summarises the procedure of development of machine learning models for the quality of bulk-tank milk in sheep and goat farms.</p>
Full article ">Figure 3
<p>Violin plots for MAPEs &lt; 10.0%, for machine learning tools used for prediction of three target values in bulk-tank milk in dairy sheep farms (green fill: k-nearest neighbours, red fill: neural networks, purple fill: random forests).</p>
Full article ">Figure 4
<p>Violin plots for MAPEs &lt; 10.0%, for machine learning tools used for prediction of three target values in bulk-tank milk in dairy goat farms (green fill: k-nearest neighbours, purple fill: random forests, red fill: neural networks).</p>
Full article ">Figure 5
<p>SHapley Additive exPlanations values for the importance of the various independent variables employed in the prediction of three target values (with MAPEs &lt; 10.0%) in bulk-tank milk of sheep farms through computational machine learning models.(clockwise from top left: protein content (k-nearest neighbours), fat and protein content (neural networks), somatic cell counts (random forests), somatic cell counts (k-nearest neighbours); independent variables shown on vertical axis of each graph: A is the presence of milking parlour, B is the month into lactation period at sampling, C is the month of start of milking period, D is the annual incidence rate of clinical mastitis, E is the age of newborns taken away from their dam, G is the age of farmer, H is the education of farmer, I is the body condition score of female animals, K is the animal breed, L is the grazing of animals, P is the provision of concentrates to animals, N is the management system applied in farm, and O is the administration of anthelmintics at last stage of pregnancy; red dots: high feature values, blue dots: low feature values).</p>
Full article ">Figure 6
<p>SHapley Additive exPlanations values for the importance of the various independent variables employed in the prediction of three target values (with MAPEs &lt; 10.0%) in bulk-tank milk of goat farms through computational machine learning models. (clockwise from top left: protein content (k-nearest neighbours), somatic cell counts (random forests), somatic cell counts (k-nearest neighbours), total bacterial counts (neural networks); independent variables shown on vertical axis of each graph: B is the month into lactation period at sampling, C is the month of start of milking period, D is the annual incidence rate of clinical mastitis, F is the annual milk production per animal, I is the body condition score of female animals, J is the number of daily milking sessions, K is the animal breed, V is the type of milking parlour, and W is the No. of animals in farm; red dots: high feature values; blue dots: low feature values).</p>
Full article ">
16 pages, 3565 KiB  
Article
An On-Machine Measuring Apparatus for Dimension and Form Errors of Deep-Hole Parts
by Jintao Liang, Xiaotian Song, Kaixin Wang and Xiaolan Han
Sensors 2024, 24(23), 7847; https://doi.org/10.3390/s24237847 - 8 Dec 2024
Viewed by 347
Abstract
The precise measurement of inner dimensions and contour accuracy is required for deep-hole parts, particularly during the manufacturing process, to monitor quality and obtain real-time error parameters. However, on-machine measurement is challenging due to the limited inner space of deep holes. This study [...] Read more.
The precise measurement of inner dimensions and contour accuracy is required for deep-hole parts, particularly during the manufacturing process, to monitor quality and obtain real-time error parameters. However, on-machine measurement is challenging due to the limited inner space of deep holes. This study proposes an automatic on-machine measuring apparatus for assessing inner diameter, straightness, and roundness errors. Based on the axial-section measurement principle, an integrated measuring module was designed, including a self-centering mechanism, a diameter measuring sensor, and a positioning reference sensor, all embedded within a control system. On this basis, calculations of the inner diameter, and evaluations of the straightness and roundness errors are presented. Experimental verification is conducted on a blind deep hole with a nominal 100 mm inner diameter and 700 mm depth. Compared with measurements performed on a coordinate measuring machine (CMM), which is limited to a maximum hole depth of 300 mm, the proposed apparatus achieved full-depth on-machine measurements. Meanwhile, the measurement results were consistent with the data obtained by the CMM. The straightness error is considered less than 0.05 mm, and the roundness error is considered less than 0.015 mm. Ultimately, without requiring any additional reference platform, the proposed apparatus shows promise for measuring deep-hole parts on various machine tools, with diameters of no less than 80 mm and theoretically unlimited hole depth. Full article
Show Figures

Figure 1

Figure 1
<p>Measurement principle of the axial-section method for deep-hole.</p>
Full article ">Figure 2
<p>Schematic diagram of three-point centering of circular section.</p>
Full article ">Figure 3
<p>Schematic diagram of the integrated measuring module.</p>
Full article ">Figure 4
<p>Dimension parameters of the measuring apparatus.</p>
Full article ">Figure 5
<p>Prototype of the proposed measuring apparatus.</p>
Full article ">Figure 6
<p>Parameter calibration for the measuring apparatus.</p>
Full article ">Figure 7
<p>Blind hole measurement achieved by the proposed measuring apparatus.</p>
Full article ">Figure 8
<p>Straightness of the center axis with different direction axial sections. (<b>a</b>) 0°-direction axial-section; (<b>b</b>) 60°-direction axial-section; (<b>c</b>) 120°-direction axial-section.</p>
Full article ">Figure 9
<p>Blind hole measurement achieved by a CMM.</p>
Full article ">
19 pages, 491 KiB  
Review
Biotechnology Revolution Shaping the Future of Diabetes Management
by Nilima Rajpal Kundnani, Bogdan Lolescu, Anca-Raluca Dinu, Delia Mira Berceanu-Vaduva, Patrick Dumitrescu, Tudor-Paul Tamaș, Abhinav Sharma and Mihaela-Diana Popa
Biomolecules 2024, 14(12), 1563; https://doi.org/10.3390/biom14121563 - 7 Dec 2024
Viewed by 584
Abstract
Introduction: Diabetes mellitus (DM) has a millennia-long history, with early references dating back to ancient Egypt and India. However, it was not until the 20th century that the connection between diabetes and insulin was fully understood. The sequencing of insulin in the 1950s [...] Read more.
Introduction: Diabetes mellitus (DM) has a millennia-long history, with early references dating back to ancient Egypt and India. However, it was not until the 20th century that the connection between diabetes and insulin was fully understood. The sequencing of insulin in the 1950s initiated the convergence of biotechnology and diabetes management, leading to the development of recombinant human insulin in 1982. This marked the start of peptide-based therapies in DM. Recombinant peptides for DM treatment: Numerous recombinant peptides have been developed since, starting with modified insulin molecules, with the aim of bettering DM management through fine-tuning the glycemic response to insulin. Peptide-based therapies in DM have expanded substantially beyond insulin to include agonists of Glucagon-like peptide-1 receptor and Glucose-dependent insulinotropic polypeptide receptor, glucagon receptor antagonists, and even peptides exerting multiple receptor agonist effects, for better metabolic control. Insulin pumps, continuous glucose monitoring, and automated insulin delivery systems: The development of modern delivery systems combined with real-time glucose monitoring has significantly advanced diabetes care. Insulin pumps evolved from early large devices to modern sensor-augmented pumps with automated shutoff features and hybrid closed-loop systems, requiring minimal user input. The second-generation systems have demonstrated superior outcomes, proving highly effective in diabetes management. Islet cell transplantation, organoids, and biological pancreas augmentation represent innovative approaches to diabetes management. Islet cell transplantation aims to restore insulin production by transplanting donor beta cells, though challenges persist regarding graft survival and the need for immunosuppression. Organoids are a promising platform for generating insulin-producing cells, although far from clinical use. Biological pancreas augmentation relies on therapies that promote beta-cell (re)generation, reduce stress, and induce immune tolerance. Further biotechnology-driven perspectives in DM will include metabolic control via biotechnology-enabled tools such as custom-designed insulin hybrid molecules, machine-learning algorithms to control peptide release, and engineering cells for optimal peptide production and secretion. Full article
(This article belongs to the Section Biological Factors)
Show Figures

Figure 1

Figure 1
<p>Timeline of peptide development and delivery vehicles in DM management (FDA Devices and Drugs approval dates, source: <a href="http://fda.gov" target="_blank">fda.gov</a>).</p>
Full article ">
12 pages, 3096 KiB  
Article
Digital Twin-Based Smart Feeding System Design for Machine Tools
by Baris Yuce, Haobing Li, Linlin Wang and Voicu Ion Sucala
Electronics 2024, 13(23), 4831; https://doi.org/10.3390/electronics13234831 - 6 Dec 2024
Viewed by 451
Abstract
With the continuous development of intelligent manufacturing technology, the application of intelligent feed systems in modern machine tools is becoming increasingly widespread. Digital twin technology achieves the monitoring and optimization of the entire life cycle of a physical system by constructing a virtual [...] Read more.
With the continuous development of intelligent manufacturing technology, the application of intelligent feed systems in modern machine tools is becoming increasingly widespread. Digital twin technology achieves the monitoring and optimization of the entire life cycle of a physical system by constructing a virtual image of the system, while neural network controllers, with their powerful nonlinear fitting ability, can accurately capture and simulate the dynamic behavior of complex systems, providing strong support for the optimization control of intelligent feed systems. This article discusses the design and implementation of an intelligent feed system based on digital twins and neural network controllers. Firstly, this article establishes a mathematical model based on the traditional ball screw structure and analyzes the dynamic characteristics and operating mechanism of the system. Subsequently, the mathematical model is fitted using a neural network controller to improve control accuracy and system response speed. The experimental results demonstrate that the neural network controller shows good consistency in fitting traditional mathematical models, not only effectively capturing the nonlinear characteristics of the system but also maintaining stable control performance under complex operating conditions. Full article
Show Figures

Figure 1

Figure 1
<p>Proposed system structure.</p>
Full article ">Figure 2
<p>Implementation method of neural networks in an MES.</p>
Full article ">Figure 3
<p>Relationship between wear loss and wear time.</p>
Full article ">Figure 4
<p>Micro-element analysis for the shaft.</p>
Full article ">Figure 5
<p>General model for simulation.</p>
Full article ">Figure 6
<p>Sub-system describing the shaft.</p>
Full article ">Figure 7
<p>System building workflow.</p>
Full article ">Figure 8
<p>Topology architecture of proposed neural network.</p>
Full article ">Figure 9
<p>Temporal response of neural networks under low-frequency signals.</p>
Full article ">Figure 10
<p>Regression of neural network dataset.</p>
Full article ">
16 pages, 2237 KiB  
Article
Improving Process Control Through Decision Tree-Based Pattern Recognition
by Izabela Rojek, Agnieszka Kujawińska, Robert Burduk and Dariusz Mikołajewski
Electronics 2024, 13(23), 4823; https://doi.org/10.3390/electronics13234823 - 6 Dec 2024
Viewed by 382
Abstract
This paper explores the integration of decision tree classifiers in the assessment of machining process stability using control charts. The inherent variability in manufacturing processes requires a robust system for the early detection and correction of disturbances, which has traditionally relied on operators’ [...] Read more.
This paper explores the integration of decision tree classifiers in the assessment of machining process stability using control charts. The inherent variability in manufacturing processes requires a robust system for the early detection and correction of disturbances, which has traditionally relied on operators’ experience. Using decision trees, this study presents an automated approach to pattern recognition on control charts that outperforms the accuracy of human operators and neural networks. Experimental research conducted on two datasets from surface finishing processes demonstrates that decision trees can achieve perfect classification under optimal parameters. The results suggest that decision trees offer a transparent and effective tool for quality control, capable of reducing human error, improving decision making, and fostering greater confidence among company employees. These results open up new possibilities for the automation and continuous improvement of machining process control. The contribution of this research to Industry 4.0 is to enable the real-time, data-driven monitoring of machining process stability through decision tree-based pattern recognition, which improves predictive maintenance and quality control. It supports the transition to intelligent manufacturing, where process anomalies are detected and resolved dynamically, reducing downtime and increasing productivity. Full article
(This article belongs to the Special Issue Data-Centric Artificial Intelligence: New Methods for Data Processing)
Show Figures

Figure 1

Figure 1
<p>Data sources for quality control actions (own elaboration).</p>
Full article ">Figure 2
<p>An example of a control chart and examples of symptoms; the point outside the control line, a decreasing trend, and the clusters. (Legend: LCL = lower control line; CL = central line; UCL = upper central line.) The points highlighted in red are symptoms, indicating the impact of special factors on the process (own elaboration).</p>
Full article ">Figure 3
<p>Control chart as pattern set (own elaboration).</p>
Full article ">Figure 4
<p>An abbreviated structure of a decision tree for the set of parameters D11 and dataset Z5. The green node is terminal node of decision tree, and the rod node is the splitting node, STR1—Stratification.</p>
Full article ">Figure 5
<p>Error (1—Accuracy) for Z5 set for D1–D6 (Di—i-th set of parameters).</p>
Full article ">Figure 6
<p>Error (1—Accuracy) for Z5 set for D7–D10 (Di—i-th set of parameters).</p>
Full article ">Figure 7
<p>Error (1—Accuracy) for Z10 set for D1–D6 (Di—i-th set of parameters).</p>
Full article ">Figure 8
<p>Error (1—Accuracy) for Z10 set for D7–D10 (Di—i-th set of parameters).</p>
Full article ">
16 pages, 4406 KiB  
Article
Real-Time Acoustic Measurement System for Cutting-Tool Analysis During Stainless Steel Machining
by Tom Salm, Kourosh Tatar and José Chilo
Machines 2024, 12(12), 892; https://doi.org/10.3390/machines12120892 - 6 Dec 2024
Viewed by 470
Abstract
This study presents a sound-based tool-wear monitoring system designed to overcome the limitations of conventional methods that focus solely on gradual and predictable wear patterns. The proposed system employs low-cost, high-frequency microphones and advanced signal processing—featuring analog/digital filtering, oversampling, signal conditioning, PLL-based synchronization, [...] Read more.
This study presents a sound-based tool-wear monitoring system designed to overcome the limitations of conventional methods that focus solely on gradual and predictable wear patterns. The proposed system employs low-cost, high-frequency microphones and advanced signal processing—featuring analog/digital filtering, oversampling, signal conditioning, PLL-based synchronization, and feature extraction (ZCR, RMS)—to capture acoustic emissions during machining. Key innovations include optimized microphone placement, a custom PCB, and real-time data transfer via WiFi to MATLAB for analysis. Using the TreeBagger machine-learning algorithm, the system accurately predicts tool wear, detecting both gradual and abrupt wear patterns. Tested on EN 1.4307 (AISI/ASTM 304L) stainless steel, the system demonstrated robust performance in real-time tool-condition assessment. Its scalable and cost-effective design allows for the integration of additional sensors and features, providing a non-invasive and adaptive solution to enhance machining efficiency and reduce operational costs. Full article
(This article belongs to the Section Material Processing Technology)
Show Figures

Figure 1

Figure 1
<p>The flowchart of the research methodology in this article.</p>
Full article ">Figure 2
<p>Experimental setup to investigate how different shields affect audio measurements.</p>
Full article ">Figure 3
<p>Typical wear observed on the tool faces and cutting edge after turning in austenitic stainless steel. These include flank wear, rake wear, and notching. Notching was the critical indicator in this work.</p>
Full article ">Figure 4
<p>Frequency response, at 100 cm, from different shields. Sound pressure level SPL with reference to 20 µPa.</p>
Full article ">Figure 5
<p>Harmonic distortion in the Short Time Fourier Transform of sound measurements conducted inside an anechoic chamber.</p>
Full article ">Figure 6
<p>Simulated frequency response, Analog Front-End.</p>
Full article ">Figure 7
<p>Measurement system PCB schematic.</p>
Full article ">Figure 8
<p>Assembled measurement system.</p>
Full article ">Figure 9
<p>Measurement setup.</p>
Full article ">Figure 10
<p>Recorded audio data. Signals from the first 180 s.</p>
Full article ">Figure 11
<p>Recorded audio data. Full signal duration.</p>
Full article ">Figure 12
<p>Recorded audio data. Full signal duration.</p>
Full article ">Figure 13
<p>Example of features extracted from the Short Time Fourier Transform of an audio signal recorded during a cutting test, approximately at 15 s of cutting engagement. These features are used as input for the machine-learning algorithm.</p>
Full article ">Figure 14
<p>Tool lifetime in [hh:mm:ss].</p>
Full article ">Figure 15
<p>Average surface roughness trend.</p>
Full article ">
17 pages, 11854 KiB  
Article
Digitalization of an Industrial Process for Bearing Production
by Jose-Manuel Rodriguez-Fortun, Jorge Alvarez, Luis Monzon, Ricardo Salillas, Sergio Noriega, David Escuin, David Abadia, Aitor Barrutia, Victor Gaspar, Jose Antonio Romeo, Fernando Cebrian and Rafael del-Hoyo-Alonso
Sensors 2024, 24(23), 7783; https://doi.org/10.3390/s24237783 - 5 Dec 2024
Viewed by 498
Abstract
The developments in sensing, actuation, and algorithms, both in terms of Artificial Intelligence (AI) and data treatment, have open up a wide range of possibilities for improving the quality of the production systems in diverse industrial fields. The present paper describes the automatizing [...] Read more.
The developments in sensing, actuation, and algorithms, both in terms of Artificial Intelligence (AI) and data treatment, have open up a wide range of possibilities for improving the quality of the production systems in diverse industrial fields. The present paper describes the automatizing process performed in a production line for high-quality bearings. The actuation considered new sensing elements at the machine level and the treatment of the information, fusing the different sources in order to detect quality defects in the grinding process (waviness, burns) and monitoring the state of the tool. At a supervision level, an AI model has been developed for monitoring the complete line and compensating deviations in the dimension of the final assembly. The project also contemplated the hardware architecture for improving the data acquisition and communication among the machines and databases, the data treatment units, and the human interfaces. The resulting system gives feedback to the operator when deviations or potential errors are detected so that the quality issues are recognized and can be amended in advance, thereby reducing the quality cost. Full article
Show Figures

Figure 1

Figure 1
<p>Simplified schema with the main elements of the FERSA production line.</p>
Full article ">Figure 2
<p>Main elements in the architecture.</p>
Full article ">Figure 3
<p>Sensors in the figure framed with a red circle: (<b>upper left</b>) accelerometer (PCB Piezotronics with a frequency range of 0.5 to 8000 Hz); (<b>upper right</b>) Equipment for grinding power acquisition; (<b>lower left</b>) thermal camera (FLIR Lepton 3.5); (<b>lower right</b>) AE sensor (Steminc 20 × 1 mm 2 Mhz R).</p>
Full article ">Figure 4
<p>Description of the traceability blockchain architecture.</p>
Full article ">Figure 5
<p>Speed algorithm global architecture.</p>
Full article ">Figure 6
<p>Post-manufacturing quality process result for waviness analysis. Purple line shows the threshold harmonic content for the waviness appearance. Light blue line shows 80% probability threshold for waviness appearance.</p>
Full article ">Figure 7
<p>Thermal image obtained during the grinding process.</p>
Full article ">Figure 8
<p>Schematic example of the virtual sensor solution for thermal damage prediction based on the grinding power measurement and the calculation of the limiting value.</p>
Full article ">Figure 9
<p>Tool profile estimation with maximum, minimum, mean, and RMS values.</p>
Full article ">Figure 10
<p>Evolution of RMS value over consecutive dressing operations.</p>
Full article ">Figure 11
<p>Line dimensional control.</p>
Full article ">Figure 12
<p>Comparison between the predicted harmonic content and the result from the offline quality control.</p>
Full article ">Figure 13
<p>Comparison of the predicted harmonic content and the limits of the waviness protocol.</p>
Full article ">Figure 14
<p>Results of thermal damage for different tests and validation of the prediction tool. The blue line represents the thermal limit and the dots represent the measured power. The circled dots show the workpieces that presented burns during the quality control.</p>
Full article ">Figure 15
<p>Values predicted by the dimensional line model versus actual values measured on the control machine. Scatter plot (<b>left</b>); 2D histogram (<b>right</b>).</p>
Full article ">Figure 16
<p>Recommended production pattern based on operating point (each number/color represents a production pattern). Units are not displayed due to Fersa’s privacy policy.</p>
Full article ">Figure 17
<p>Example of the interface for the assembly quality control.</p>
Full article ">Figure 18
<p>Example of the interface for the grinding quality control.</p>
Full article ">
56 pages, 26566 KiB  
Review
A Review of Intelligentization System and Architecture for Ultra-Precision Machining Process
by Minghua Pan, Guoqing Zhang, Wenqi Zhang, Jiabao Zhang, Zejiang Xu and Jianjun Du
Processes 2024, 12(12), 2754; https://doi.org/10.3390/pr12122754 - 4 Dec 2024
Viewed by 625
Abstract
The intelligence of ultra-precision machining processes has become a research focus in the field of precision and ultra-precision manufacturing. Scholars have conducted some fragmented studies on the intelligence of ultra-precision machining processes; however, a systematic review and summary of the intelligent systems and [...] Read more.
The intelligence of ultra-precision machining processes has become a research focus in the field of precision and ultra-precision manufacturing. Scholars have conducted some fragmented studies on the intelligence of ultra-precision machining processes; however, a systematic review and summary of the intelligent systems and architectures for such processes are still lacking. Therefore, this paper is devoted to reviewing the intelligent systems and architectures for ultra-precision machining processes, focusing on three aspects: machining environment monitoring, cutting process analysis, and intelligent machining system frameworks. The paper first provides an overview of environmental intelligence monitoring from the perspective of the machining environment and then discusses and summarizes monitoring processes, such as tool errors, tool wear, tool setting, and surface measurement, from the perspective of machining process analysis. The intelligent machining system framework is then analyzed and summarized from the perspective of process control. Finally, the paper outlines the overall framework of the intelligent system for ultra-precision machining processes and analyzes its components. This paper provides guidance for the development of intelligent systems in ultra-precision machining processes. Full article
Show Figures

Figure 1

Figure 1
<p>The intelligent system architecture of ultra-precision machining process is summarized through (<b>a</b>) a deep learning model for vibration monitoring [<a href="#B24-processes-12-02754" class="html-bibr">24</a>]. Reproduced with permission from author, Advances in Engineering Software, Elsevier, 2023. (<b>b</b>) Milling tool surface temperature monitoring model [<a href="#B25-processes-12-02754" class="html-bibr">25</a>]. Reproduced with permission from author, International journal of Machine Tools and Manufacture, Elsevier, 2013. (<b>c</b>) Center error identification model based on cutting force signals [<a href="#B26-processes-12-02754" class="html-bibr">26</a>]. Reproduced with permission from author, Journal of Manufacturing Processes, Elsevier, 2022. (<b>d</b>) Tool wear monitoring methods [<a href="#B27-processes-12-02754" class="html-bibr">27</a>]. (<b>e</b>) Dynamic balance measurement and adjustment methods [<a href="#B28-processes-12-02754" class="html-bibr">28</a>,<a href="#B29-processes-12-02754" class="html-bibr">29</a>,<a href="#B30-processes-12-02754" class="html-bibr">30</a>,<a href="#B31-processes-12-02754" class="html-bibr">31</a>]. (<b>f</b>) Miniature optical tool-setting device [<a href="#B22-processes-12-02754" class="html-bibr">22</a>]. Reproduced with permission from author, Journal of Sensors and Sensor Systems, Copernicus Publications, 2014. (<b>g</b>) Ultrasonic vibration-assisted milling system [<a href="#B23-processes-12-02754" class="html-bibr">23</a>]. (<b>h</b>) Edge intelligence algorithmic framework [<a href="#B32-processes-12-02754" class="html-bibr">32</a>]. Reproduced with permission from author, Engineering Science and Technology, an International Journal, Elsevier, 2023. (<b>i</b>) Block diagram of adaptive control system with feedback regulation [<a href="#B33-processes-12-02754" class="html-bibr">33</a>].</p>
Full article ">Figure 2
<p>(<b>a</b>) Block diagram of chatter detection based on cross-domain migration learning algorithm [<a href="#B35-processes-12-02754" class="html-bibr">35</a>]. Reproduced with permission from author, Engineering Science and Technology, an International Journal, Elsevier, 2022. (<b>b</b>) Intelligent monitoring system architecture for machining process [<a href="#B39-processes-12-02754" class="html-bibr">39</a>]. Reproduced with permission from author, CIRP Annals—Manufacturing Technology, Elsevier, 2023. (<b>c</b>) Block diagram of the embedded thin-film thermocouple real-time temperature measurement system [<a href="#B36-processes-12-02754" class="html-bibr">36</a>]. Reproduced with permission from author, Procedia CIRP, Elsevier, 2018.</p>
Full article ">Figure 3
<p>Vibration monitoring block diagram: (<b>a</b>) Vibration recognition model based on CNC system signals [<a href="#B53-processes-12-02754" class="html-bibr">53</a>]. Reproduced with permission from author, Mechanical Systems and Signal Processing, Elsevier, 2023. (<b>b</b>) Vibration monitoring model based on transfer learning algorithm [<a href="#B54-processes-12-02754" class="html-bibr">54</a>]. Reproduced with permission from author, Journal of Manufacturing Processes, Elsevier, 2022. (<b>c</b>) Vibration monitoring block diagram based on the anti-noise convolutional neural network [<a href="#B55-processes-12-02754" class="html-bibr">55</a>]. Reproduced with permission from author, Mechanical Systems and Signal Processing, Elsevier, 2024.</p>
Full article ">Figure 4
<p>Real-time monitoring system block diagram for tool temperature in the drilling process. (<b>a</b>) Temperature measurement system connection block diagram, (<b>b</b>) thermocouple installation position, (<b>c</b>) Temperature monitoring experimental results graph [<a href="#B58-processes-12-02754" class="html-bibr">58</a>]. Reproduced with permission from author, Composite Structures, Elsevier, 2017.</p>
Full article ">Figure 5
<p>Artificial intelligence for machining process monitoring [<a href="#B66-processes-12-02754" class="html-bibr">66</a>]. Reproduced with permission from author, Elsevier Books, Elsevier, 2024.</p>
Full article ">Figure 6
<p>Tool-error-zones: (<b>a</b>) uncertainty zone at the tool feed end, (<b>b</b>) workpiece end cut delineation region, (<b>c</b>) two dimensional tool-center-error subscript expression, (<b>d</b>) residual morphology evolution at the workpiece center and cutting force distribution in the absence of tool vertical error, (<b>e</b>) residual morphology evolution at the workpiece center and cutting force distribution under vertical tool-center- errors, and (<b>f</b>) residual morphology evolution at the workpiece center and cutting force distribution due to vertical errors above the tool center. Ref. [<a href="#B67-processes-12-02754" class="html-bibr">67</a>] reproduced with permission from author, Precision Engineering, Elsevier, 2021.</p>
Full article ">Figure 7
<p>The evolution of the central cone under different tool errors. (<b>a</b>) the three-dimensional cone formed when the tool height error is 200 µm, (<b>b</b>) the three-dimensional cone formed when the tool height error is 130 µm, (<b>c</b>) the three-dimensional cone formed when the tool height error is 50 µm, (<b>d</b>) the three-dimensional cone formed when the tool height error is 0 µm. Ref. [<a href="#B71-processes-12-02754" class="html-bibr">71</a>] reproduced with permission from author, International journal of Mechanical Sciences, Elsevier, 2020.</p>
Full article ">Figure 8
<p>Diagram of center error identification process. (<b>a</b>) Cutting force signal measurement and collection device, (<b>b</b>) center error identification process, and (<b>c</b>) cutting force signal fitting results. Ref. [<a href="#B26-processes-12-02754" class="html-bibr">26</a>] reproduced with permission from author, Journal of Manufacturing Processes, Elsevier, 2022.</p>
Full article ">Figure 9
<p>Schematic diagram of online diamond tool wear monitoring system. (<b>a</b>) Schematic diagram of tool wear monitoring for the ultra-precision machine, (<b>b</b>) spectral analysis of grinding force signals, and (<b>c</b>) spectral analysis of the signals during tool grinding process. Ref. [<a href="#B86-processes-12-02754" class="html-bibr">86</a>] reproduced with permission from author, International Journal of Machine Tools and Manufacture, Elsevier, 1999.</p>
Full article ">Figure 10
<p>(<b>a</b>) Framework of tool wear monitoring system based on neural network algorithm [<a href="#B91-processes-12-02754" class="html-bibr">91</a>]. Reproduced with permission from author, Journal of Manufacturing Systems, Elsevier, 2021. (<b>b</b>) Tool wear monitoring framework based on deep learning network structure [<a href="#B92-processes-12-02754" class="html-bibr">92</a>]. Reproduced with permission from author, Measurement, Elsevier, 2023.</p>
Full article ">Figure 11
<p>Prediction results of tool wear using a deep learning model [<a href="#B98-processes-12-02754" class="html-bibr">98</a>]. Reproduced with permission from author, Wear, Elsevier, 2021.</p>
Full article ">Figure 12
<p>Framework for intelligent monitoring of tool wear.</p>
Full article ">Figure 13
<p>The testing topography of the workpiece surface under different spindle speeds and balance weights. (<b>a</b>) <span class="html-italic">n</span> = 1000 r/min, 1 g mass; (<b>b</b>) <span class="html-italic">n</span> = 1200 r/min, 1 g mass; (<b>c</b>) <span class="html-italic">n</span> = 1000 r/min; (<b>d</b>) <span class="html-italic">n</span> = 1000 r/min. Ref. [<a href="#B104-processes-12-02754" class="html-bibr">104</a>] reproduced with permission from author, International journal of Machine Tools and Manufacture, Elsevier, 2017.</p>
Full article ">Figure 14
<p>The impact of spindle error on the workpiece surface at different spindle speeds. Speeds of (<b>a</b>) 40,000 rpm; (<b>b</b>) 40,200 rpm; (<b>c</b>) 40,400 rpm; and (<b>d</b>) 41,000 rpm. Ref. [<a href="#B111-processes-12-02754" class="html-bibr">111</a>] reproduced with permission from author, International journal of Mechanical Sciences, Elsevier, 2022.</p>
Full article ">Figure 15
<p>The results of rapid tool alignment experiments using optical instruments. Ref. [<a href="#B124-processes-12-02754" class="html-bibr">124</a>] reproduced with permission from author, CIRP Annals—Manufacturing Technology, Elsevier, 2019.</p>
Full article ">Figure 16
<p>Algorithm for tool setting and cutting edge arc calculation. (<b>a</b>) Precision tool setup and experimental results for fabricating microstructure arrays [<a href="#B130-processes-12-02754" class="html-bibr">130</a>]. Reproduced with permission from author, CIRP Annals—Manufacturing Technology, Elsevier, 2013. (<b>b</b>) Algorithm for cutting edge arc calculation and experimental results [<a href="#B136-processes-12-02754" class="html-bibr">136</a>]. Reproduced with permission from author, Journal of Advanced Mechanical Design, Systems, and Manufacturing, JSTAGE, 2014.</p>
Full article ">Figure 17
<p>Optical instrument for multidimensional measurement of diamond tools. Ref. [<a href="#B140-processes-12-02754" class="html-bibr">140</a>] reproduced with permission from author, Measurement, Elsevier, 2016.</p>
Full article ">Figure 18
<p>(<b>A</b>) Diagram shows a one-dimensional ultrasonic vibration-assisted system, (<b>A1</b>) shows the resonant one-dimensional vibration-assisted machining of the tool, and (<b>A2</b>) shows the resonance of the workpiece; (<b>B</b>) a two-dimensional ultrasonic vibration-assisted system, (<b>B1</b>) non-resonant two-dimensional vibration-assisted machining of the tool, (<b>B2</b>) non-resonant two-dimensional vibration-assisted machining of the workpiece, (<b>B3</b>) two-dimensional vibration-assisted machining of the tool, and (<b>B4</b>) two-dimensional vibration-assisted machining of the workpiece; (<b>C</b>) a three-dimensional ultrasonic vibration assistance system. Ref. [<a href="#B152-processes-12-02754" class="html-bibr">152</a>] reproduced with permission from author, International journal of Machine Tools and Manufacture, Elsevier, 2020.</p>
Full article ">Figure 19
<p>Laser-assisted diamond turning of silicon free-form surfaces. Ref. [<a href="#B157-processes-12-02754" class="html-bibr">157</a>] reproduced with permission from author, Journal of Materials Processing Technology, Elsevier, 2023.</p>
Full article ">Figure 20
<p>Industrial IoT intelligent manufacturing production line data-monitoring system structure. (<b>a</b>) Industrial IoT architecture, (<b>b</b>) intelligent workshop CNC machine and workstations touch screen networking solution, and (<b>c</b>) workshop wireless sensor network design architecture. Ref. [<a href="#B164-processes-12-02754" class="html-bibr">164</a>] reproduced with permission from author, Computer Communications, Elsevier, 2020.</p>
Full article ">Figure 21
<p>Structure of intelligent scheduling algorithms for intelligent factories. Ref. [<a href="#B174-processes-12-02754" class="html-bibr">174</a>] reproduced with permission from author, Journal of Manufacturing Systems, Elsevier, 2022.</p>
Full article ">Figure 22
<p>Intelligent system architecture for ultra-precision machining process.</p>
Full article ">Figure 23
<p>An open, integrated precision motion control system. (<b>a</b>) Overall structure of the control system. (<b>b</b>) Schematic diagram comparing the experimental results. Ref. [<a href="#B186-processes-12-02754" class="html-bibr">186</a>] reproduced with permission from author, Control Engineering Practice, Elsevier, 2002.</p>
Full article ">Figure 24
<p>(<b>a</b>) Process data transmission and monitoring. Ref. [<a href="#B201-processes-12-02754" class="html-bibr">201</a>] reproduced with permission from author, Measurement, Elsevier, 2023. (<b>b</b>) Iterative optimization framework for different types of data. Ref. [<a href="#B202-processes-12-02754" class="html-bibr">202</a>] reproduced with permission from author, IEEE Access, IEEE, 2017.</p>
Full article ">Figure 25
<p>(<b>a</b>) The model of human–computer collaboration under digital twin. (<b>b</b>) The model of human–computer collaboration with visual question-and-answer technology. Ref. [<a href="#B209-processes-12-02754" class="html-bibr">209</a>] reproduced with permission from author, Journal of Manufacturing Systems, Elsevier, 2021.</p>
Full article ">
20 pages, 2824 KiB  
Article
Hydrakon, a Framework for Measuring Indicators of Deception in Emulated Monitoring Systems
by Kon Papazis and Naveen Chilamkurti
Future Internet 2024, 16(12), 455; https://doi.org/10.3390/fi16120455 - 4 Dec 2024
Viewed by 338
Abstract
The current cybersecurity ecosystem is proving insufficient in today’s increasingly sophisticated cyber attacks. Malware authors and intruders have pursued innovative avenues to circumvent emulated monitoring systems (EMSs) such as honeypots, virtual machines, sandboxes and debuggers to continue with their malicious activities while remaining [...] Read more.
The current cybersecurity ecosystem is proving insufficient in today’s increasingly sophisticated cyber attacks. Malware authors and intruders have pursued innovative avenues to circumvent emulated monitoring systems (EMSs) such as honeypots, virtual machines, sandboxes and debuggers to continue with their malicious activities while remaining inconspicuous. Cybercriminals are improving their ability to detect EMS, by finding indicators of deception (IoDs) to expose their presence and avoid detection. It is proving a challenge for security analysts to deploy and manage EMS to evaluate their deceptive capability. In this paper, we introduce the Hydrakon framework, which is composed of an EMS controller and several Linux and Windows 10 clients. The EMS controller automates the deployment and management of the clients and EMS for the purpose of measuring EMS deceptive capabilities. Experiments were conducted by applying custom detection vectors to client real machines, virtual machines and sandboxes, where various artifacts were extracted and stored as csv files on the EMS controller. The experiment leverages the cosine similarity metric to compare and identify similar artifacts between a real system and a virtual machine or sandbox. Our results show that Hydrakon offers a valid approach to assess the deceptive capabilities of EMS without the need to target specific IoD within the target system, thereby fostering more robust and effective emulated monitoring systems. Full article
Show Figures

Figure 1

Figure 1
<p>Hydrakon architecture containing several components and modules.</p>
Full article ">Figure 2
<p>Workflow cloning and deploying clients via FOG server.</p>
Full article ">Figure 3
<p>EMS controller main menu.</p>
Full article ">Figure 4
<p>EMS threat evasion model encapsulating the distinction of evasive vectors applied to indicators of deception to a given EMS security tool.</p>
Full article ">Figure 5
<p>EMS threat evasion methodology showing the phases involved in evaluating an EMS security tool’s deceptive nature.</p>
Full article ">Figure 6
<p>EMS evasive vectors workflow to evaluate the similarity of target systems using cosine similarity.</p>
Full article ">Figure 7
<p>Display cosine similarity of bare metal, virtual machine and sandbox artifacts in graph format.</p>
Full article ">
30 pages, 4591 KiB  
Article
Machine Learning Classification of Pediatric Health Status Based on Cardiorespiratory Signals with Causal and Information Domain Features Applied—An Exploratory Study
by Maciej Rosoł, Jakub S. Gąsior, Kacper Korzeniewski, Jonasz Łaba, Robert Makuch, Bożena Werner and Marcel Młyńczak
J. Clin. Med. 2024, 13(23), 7353; https://doi.org/10.3390/jcm13237353 - 2 Dec 2024
Viewed by 407
Abstract
Background/Objectives: This study aimed to evaluate the accuracy of machine learning (ML) techniques in classifying pediatric individuals—cardiological patients, healthy participants, and athletes—based on cardiorespiratory features from short-term static measurements. It also examined the impact of cardiorespiratory coupling (CRC)-related features (from causal and information [...] Read more.
Background/Objectives: This study aimed to evaluate the accuracy of machine learning (ML) techniques in classifying pediatric individuals—cardiological patients, healthy participants, and athletes—based on cardiorespiratory features from short-term static measurements. It also examined the impact of cardiorespiratory coupling (CRC)-related features (from causal and information domains) on the modeling accuracy to identify a preferred cardiorespiratory feature set that could be further explored for specialized tasks, such as monitoring training progress or diagnosing health conditions. Methods: We utilized six self-prepared datasets that comprised various subsets of cardiorespiratory parameters and applied several ML algorithms to classify subjects into three distinct groups. This research also leveraged explainable artificial intelligence (XAI) techniques to interpret model decisions and investigate feature importance. Results: The highest accuracy, over 89%, was obtained using the dataset that included most important demographic, cardiac, respiratory, and interrelated (causal and information) domain features. The dataset that comprised the most influential features but without demographic data yielded the second best accuracy, equal to 85%. Incorporation of the causal and information domain features significantly improved the classification accuracy. The use of XAI tools further highlighted the importance of these features with respect to each individual group. Conclusions: The integration of ML algorithms with a broad spectrum of cardiorespiratory features provided satisfactory efficiency in classifying pediatric individuals into groups according to their actual health status. This study underscored the potential of ML and XAI in advancing the analysis of cardiorespiratory signals and emphasized the importance of CRC-related features. The established set of features that appeared optimal for the classification of pediatric patients should be further explored for their potential in assessing individual progress through training or rehabilitation. Full article
Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
<p>Placement of the electrodes used for the ECG and IP measurements.</p>
Full article ">Figure 2
<p>Examples of TV time series in the top chart and tachogram (blue line) with an individual RRi (red dots) in the bottom chart for Healthy subject #40.</p>
Full article ">Figure 3
<p>Diagram presenting the individual steps of the conducted analysis.</p>
Full article ">Figure 4
<p>Distributions of the demographical parameters presented as boxplots. The central green line represents the median. Outliers, if present, are shown as individual points.</p>
Full article ">Figure 5
<p>Violin plots of the metric values obtained from the cross-validation for each dataset. The metrics obtained from the individual iterations of 10-fold cross validation are presented as black dots.</p>
Full article ">Figure 6
<p><span class="html-italic">p</span>-values from the Wilcoxon signed-rank test that compared the metrics obtained for individual datasets from individual iterations of 10-fold cross-validation. <span class="html-italic">p</span>-values smaller than 0.05, indicating statistically significant difference in the metric values, are highlighted with black backgrounds.</p>
Full article ">Figure 7
<p>ROC and AUC values obtained for each considered dataset. The dashed black line represents the line of identity.</p>
Full article ">Figure 8
<p>Cumulative confusion matrices obtained by summing the confusion matrices from the test set in each iteration of the 10-fold cross-validation for each considered dataset.</p>
Full article ">Figure 9
<p>Shapley values obtained for the test data from the cross-validation for D3 (on the left) and D4 (on the right). The horizontal axis represents the SHAP value, which reflects the impact of each feature on the model’s output. The vertical axis lists the features in order of importance, with the most influential features at the top. The color of each dot represents the feature value for each data point: red dots correspond to high feature values, while blue dots correspond to low feature values.</p>
Full article ">Figure 10
<p>Shapley values obtained for the test data from the cross-validation for D5 (on the left) and D6 (on the right). The horizontal axis represents the SHAP value, which reflects the impact of each feature on the model’s output. The vertical axis lists the features in order of importance, with the most influential features at the top. The color of each dot represents the feature value for each data point: red dots correspond to high feature values, while blue dots correspond to low feature values.</p>
Full article ">Figure 11
<p>The mean values of dropout-loss variable importance are presented as bar plots with the standard deviation (red solid lines) for each class separately with a one vs. all approach applied for its calculations. The mean and standard deviation were calculated from the values of variable importance obtained at each iteration of the 10-fold cross-validation. The results for D3 are presented on the left and for D4 on the right.</p>
Full article ">Figure 12
<p>The mean values of the dropout-loss variable importance are presented as bar plots with the standard deviation (red solid lines) for each class separately with a one vs. all approach applied for its calculations. The mean and standard deviation were calculated from the values of variable importance obtained at each iteration of the 10-fold cross-validation. The results for D5 are presented on the left and for D6 on the right.</p>
Full article ">
16 pages, 3930 KiB  
Article
Spectral Fingerprinting of Tencha Processing: Optimising the Detection of Total Free Amino Acid Content in Processing Lines by Hyperspectral Analysis
by Qinghai He, Yihang Guo, Xiaoli Li, Yong He, Zhi Lin and Hui Zeng
Foods 2024, 13(23), 3862; https://doi.org/10.3390/foods13233862 - 29 Nov 2024
Viewed by 472
Abstract
The quality and flavor of tea leaves are significantly influenced by chemical composition, with the content of free amino acids serving as a key indicator for assessing the quality of Tencha. Accurately and quickly measuring free amino acids during tea processing is crucial [...] Read more.
The quality and flavor of tea leaves are significantly influenced by chemical composition, with the content of free amino acids serving as a key indicator for assessing the quality of Tencha. Accurately and quickly measuring free amino acids during tea processing is crucial for monitoring and optimizing production processes. However, traditional chemical analysis methods are often time-consuming and costly, limiting their application in real-time quality control. Hyperspectral imaging (HSI) has shown significant effectiveness as a component detection tool in various agricultural applications. This study employs VNIR-HSI combined with machine learning algorithms to develop a model for visualizing the total free amino acid content in Tencha samples that have undergone different processing steps on the production line. Four pretreating methods were employed to preprocess the spectra, and partial least squares regression (PLSR) and least squares support vector machine regression (LS–SVR) models were established from the perspectives of individual processes and the entire process. Combining competitive adaptive reweighted sampling (CARS) and variable iterative space shrinkage approach (VISSA) methods for characteristic band selection, specific bands were chosen to predict the amino acid content. By comparing modeling evaluation indicators for each model, the optimal model was identified: the overall model CT+CARS+PLSR, with predictive indicators Rc2 = 0.9885, Rp2 = 0.9566, RMSEC = 0.0956, RMSEP = 0.1749, RPD = 4.8021, enabling the visualization of total free amino acid content in processed Tencha leaves. Here, we establish a benchmark for machine learning-based HSI, integrating this technology into the tea processing workflow to provide a real-time decision support tool for quality control, offering a novel method for the rapid and accurate prediction of free amino acids during tea processing. This achievement not only provides a scientific basis for the tea processing sector but also opens new avenues for the application of hyperspectral imaging technology in food science. Full article
(This article belongs to the Section Food Engineering and Technology)
Show Figures

Figure 1

Figure 1
<p>Three processing steps of Tencha: (<b>A</b>) fresh leaves spreading, (<b>B</b>) steaming fixation, and (<b>C</b>) hot air drying.</p>
Full article ">Figure 2
<p>Experimental platform for collecting hyperspectral information.</p>
Full article ">Figure 3
<p>The mean spectra of different processes for Tencha (<b>A</b>); amino acid content of JK samples after different processes (<b>B</b>).</p>
Full article ">Figure 4
<p>Four pretreated spectrograms for all acquisitions: (<b>A</b>) spectra after MSC; (<b>B</b>) spectra after CT; (<b>C</b>) spectra after D1; (<b>D</b>) spectra after SG.</p>
Full article ">Figure 5
<p>Variation of each parameter with increasing number of iterations in the CARS characteristic selection method under the best pretreated global model (<b>A</b>); Variation of the number of iterations for RMSECV during VISSA characteristic selection method under the best pretreated global model (<b>B</b>).</p>
Full article ">Figure 6
<p>Plot of band positions for CARS characteristic selection in models after optimal pretreatment (<b>A</b>); plot of band positions for VISSA characteristic selection in models after optimal pretreatment (<b>B</b>).</p>
Full article ">Figure 7
<p>Scatterplot of the best model under different modelling approaches: (<b>A</b>) CT–CARS–PLSR; (<b>B</b>) D1–VISSA–LSSVR.</p>
Full article ">Figure 8
<p>Visualization of amino acid content in milled tea from different processes based on visible NIR spectroscopy; (<b>A</b>) FLS processing; (<b>B</b>) SF processing; (<b>C</b>) HD processing.</p>
Full article ">
24 pages, 8214 KiB  
Review
Recent Advancements in Guided Ultrasonic Waves for Structural Health Monitoring of Composite Structures
by Mohad Tanveer, Muhammad Umar Elahi, Jaehyun Jung, Muhammad Muzammil Azad, Salman Khalid and Heung Soo Kim
Appl. Sci. 2024, 14(23), 11091; https://doi.org/10.3390/app142311091 - 28 Nov 2024
Viewed by 545
Abstract
Structural health monitoring (SHM) is essential for ensuring the safety and longevity of laminated composite structures. Their favorable strength-to-weight ratio renders them ideal for the automotive, marine, and aerospace industries. Among various non-destructive testing (NDT) methods, ultrasonic techniques have emerged as robust tools [...] Read more.
Structural health monitoring (SHM) is essential for ensuring the safety and longevity of laminated composite structures. Their favorable strength-to-weight ratio renders them ideal for the automotive, marine, and aerospace industries. Among various non-destructive testing (NDT) methods, ultrasonic techniques have emerged as robust tools for detecting and characterizing internal flaws in composites, including delaminations, matrix cracks, and fiber breakages. This review concentrates on recent developments in ultrasonic NDT techniques for the SHM of laminated composite structures, with a special focus on guided wave methods. We delve into the fundamental principles of ultrasonic testing in composites and review cutting-edge techniques such as phased array ultrasonics, laser ultrasonics, and nonlinear ultrasonic methods. The review also discusses emerging trends in data analysis, particularly the integration of machine learning and artificial intelligence for enhanced defect detection and characterization through guided waves. This review outlines the current and anticipated trends in ultrasonic NDT for SHM in composites, aiming to aid researchers and practitioners in developing more effective monitoring strategies for laminated composite structures. Full article
(This article belongs to the Special Issue Application of Ultrasonic Non-destructive Testing)
Show Figures

Figure 1

Figure 1
<p>Framework of the ultrasonic guided wave-based structural health monitoring process for composite materials.</p>
Full article ">Figure 2
<p>(<b>a</b>) Common failure modes of CFRP composites and (<b>b</b>) typical damage types of composite materials during processing and service periods.</p>
Full article ">Figure 3
<p>Visualization of the propagation of ultrasonic waves in composite materials on (<b>a</b>) face A, (<b>b</b>) face B, and (<b>c</b>) face C [<a href="#B63-applsci-14-11091" class="html-bibr">63</a>].</p>
Full article ">Figure 4
<p>Flow diagram for imaging deterioration in composite materials using TFM imaging [<a href="#B62-applsci-14-11091" class="html-bibr">62</a>].</p>
Full article ">Figure 5
<p>The Lamb-wave-based air-coupled ultrasonic testing device detects delamination flaws in carbon fiber composite plates [<a href="#B92-applsci-14-11091" class="html-bibr">92</a>].</p>
Full article ">Figure 6
<p>Experimental setup for guided wave testing, depicting the B-scan at 90° [<a href="#B99-applsci-14-11091" class="html-bibr">99</a>].</p>
Full article ">Figure 7
<p>Experimental setup of the PAUT guided wave technique for identifying faults in CFRP samples [<a href="#B100-applsci-14-11091" class="html-bibr">100</a>].</p>
Full article ">Figure 8
<p>Comparing the contrast and background noise between traditional methods and the FAD technique using electronic beam steering along the fracture direction [<a href="#B104-applsci-14-11091" class="html-bibr">104</a>].</p>
Full article ">Figure 9
<p>Damage localization flowchart using the GAF–CNN–CBAM model for damage localization. Reprinted with permission from ref. [<a href="#B120-applsci-14-11091" class="html-bibr">120</a>].</p>
Full article ">
Back to TopTop