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22 pages, 238 KB  
Article
UK—A Century of Failing (and Sometimes Succeeding) at Value Capture
by Richard Grover
Land 2025, 14(5), 936; https://doi.org/10.3390/land14050936 - 25 Apr 2025
Viewed by 782
Abstract
The United Kingdom has had a series of unsuccessful attempts at securing land value capture in 1909, 1947, 1967, and 1975. The 1909 land duties would have taxed increases in land values irrespective of the source. The latter three combined public bodies, acquiring [...] Read more.
The United Kingdom has had a series of unsuccessful attempts at securing land value capture in 1909, 1947, 1967, and 1975. The 1909 land duties would have taxed increases in land values irrespective of the source. The latter three combined public bodies, acquiring development land with levies on developers. For them, value uplift was limited to that arising from the granting of planning consent. None of the measures were fully implemented and were reversed by incoming governments. One of the key problems with value capture policies has been the lack of political consensus. Since 1979, consensus has developed around the use of three types of value capture instruments. Development corporations have been created for the regeneration of local areas by acquiring development land and improving it. Local authorities have been able to use planning obligations and community infrastructure levies to oblige developers to mitigate externalities. Governments have made it clear that these are not to be used as value capture devices and therefore are really applications of the polluter pays principle. Thirdly, there are national taxes that fall on increases in the value of land, namely, business rates, stamp duty land tax, capital gains tax, and inheritance tax. Full article
(This article belongs to the Special Issue Optimizing Land Development: Trends and Best Practices)
14 pages, 4140 KB  
Article
Integrating AI-Driven Predictive Analytics in Wearable IoT for Real-Time Health Monitoring in Smart Healthcare Systems
by Siriwan Kajornkasirat, Chanathip Sawangwong, Kritsada Puangsuwan, Napat Chanapai, Weerapat Phutthamongkhon and Supattra Puttinaovarat
Appl. Sci. 2025, 15(8), 4400; https://doi.org/10.3390/app15084400 - 16 Apr 2025
Cited by 1 | Viewed by 2537
Abstract
The spread of infectious diseases, such as COVID-19, presents a significant problem for public health and healthcare systems. Digital technology plays an important role in achieving access to healthcare by enhancing device connectivity and information sharing. This study aimed to develop, implement, and [...] Read more.
The spread of infectious diseases, such as COVID-19, presents a significant problem for public health and healthcare systems. Digital technology plays an important role in achieving access to healthcare by enhancing device connectivity and information sharing. This study aimed to develop, implement, and demonstrate a tracking and surveillance system to enhance monitoring for emerging infectious diseases, focusing on COVID-19 patient profiling. The system integrates IoT-based wearable devices, an artificial intelligence (AI) camera for real-time monitoring, and a MySQL database for data management. The program uses Charts.js for data visualization and Longdo Map API for mapping, leveraging Jetson Nano boards, webcams, and Python (Version 3.9). We employed a classification technique to categorize patients into two groups: those with a positive mood and those with a negative mood. For comparing accuracies, we utilized three types of models: multilayer perceptron (MLP), support vector machine (SVM), and random forest. Model validation and evaluation were conducted using Python programming. The results of this study fall into three parts. The first part involved testing the monitoring and surveillance system. It was found that the system could receive information from the wearable device, display the received data in graph form, and notify the medical staff when examining symptoms to consider whether the patient should be taken to the hospital. The second part focused on testing the device, and it was found that it could measure body temperature, heart rate, and blood oxygen levels (SpO2) and send those data to the database. The third part involved an AI camera test, and it was found that the most suitable algorithm to analyze the patient’s facial expressions was Random Forest. The results show that the system supports hospitals in managing COVID-19 and similar diseases by enabling timely interventions through facial expression analysis. Full article
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18 pages, 3530 KB  
Article
PPRD-FL: Privacy-Preserving Federated Learning Based on Randomized Parameter Selection and Dynamic Local Differential Privacy
by Jianlong Feng, Rongxin Guo and Jianqing Zhu
Electronics 2025, 14(5), 990; https://doi.org/10.3390/electronics14050990 - 28 Feb 2025
Viewed by 1497
Abstract
As traditional federated learning algorithms often fall short in providing privacy protection, a growing body of research integrates local differential privacy methods into federated learning to strengthen privacy guarantees. However, under a fixed privacy budget, with the increase in the dimensionality of model [...] Read more.
As traditional federated learning algorithms often fall short in providing privacy protection, a growing body of research integrates local differential privacy methods into federated learning to strengthen privacy guarantees. However, under a fixed privacy budget, with the increase in the dimensionality of model parameters, the privacy budget allocated per parameter diminishes, which means that a larger amount of noise is required to meet privacy requirements. This escalation in noise may adversely affect the final model’s performance. For that, we propose a privacy protection federated learning (PPRD-FL) approach. First, we design a randomized parameter selection strategy that combines randomization with importance-based filtering, effectively addressing the privacy budget dilution problem by selecting only the most crucial parameters for global aggregation. Second, we develop a dynamic local differential privacy-based perturbation mechanism, which adjusts the noise levels according to the training phase, not only providing robustness and security but also optimizing the dynamic allocation of the privacy budget. Finally, our experiments have demonstrated that the proposed approach maintains a high performance while ensuring strong privacy guarantees. Full article
(This article belongs to the Special Issue Security and Privacy in Emerging Technologies)
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18 pages, 48673 KB  
Article
A Transfer Learning Approach for Toe Walking Recognition Using Surface Electromyography on Leg Muscles
by Andrea Manni, Gabriele Rescio, Anna Maria Carluccio, Andrea Caroppo and Alessandro Leone
Sensors 2025, 25(5), 1305; https://doi.org/10.3390/s25051305 - 20 Feb 2025
Viewed by 873
Abstract
Gait is a complex motor process that involves the coordination and synchronization of various body parts through continuous interaction with the environment. Monitoring gait is crucial for the early detection of abnormalities, such as toe walking, which is characterized by limited or absent [...] Read more.
Gait is a complex motor process that involves the coordination and synchronization of various body parts through continuous interaction with the environment. Monitoring gait is crucial for the early detection of abnormalities, such as toe walking, which is characterized by limited or absent heel contact with the floor during walking. Persistent toe walking can cause severe foot, ankle, and musculature conditions; poor balance; increased risk of falling or tripping; and can affect overall quality of life, making it difficult, for example, to participate in sports or social activities. This study proposes a new approach to detect toe walking using surface Electromyography (sEMG) on lower limbs. sEMG sensors, by measuring the electrical activity of muscles, can see signals before the movement corresponding to muscle activation, contributing to an early detection of a possible problem. The sEMG signal presents significant complexity due to its noisy nature and the challenge of extracting meaningful features for classification. To address this issue and enhance the model’s robustness across different devices and configurations, a Transfer Learning (TL) approach is introduced. This method leverages pre-trained models to effectively handle the variability of sEMG data and improve classification accuracy. In particular, Continuous Wavelet Transform (CWT) is applied to sEMG-filtered signals (with time windows of 1 s) to convert them into 2D images (scalograms). Preliminary tests were performed on a public dataset using some of the most well-known pre-trained architectures, obtaining an accuracy of about 95% on InceptionResNetV2. Full article
(This article belongs to the Special Issue Biosignal Sensing Analysis (EEG, EMG, ECG, PPG) (2nd Edition))
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15 pages, 9514 KB  
Article
Improving Fall Classification Accuracy of Multi-Input Models Using Three-Axis Accelerometer and Heart Rate Variability Data
by Seunghui Kim, Jae Eun Ko, Seungbin Baek, Daechang Kim and Sungmin Kim
Sensors 2025, 25(4), 1180; https://doi.org/10.3390/s25041180 - 14 Feb 2025
Viewed by 980
Abstract
Reduced body movement and weakened musculoskeletal function as a result of aging increase the risk of falls and serious physical injuries requiring medical attention. To solve this problem, a fall prevention algorithm using an acceleration sensor has been developed, and research is being [...] Read more.
Reduced body movement and weakened musculoskeletal function as a result of aging increase the risk of falls and serious physical injuries requiring medical attention. To solve this problem, a fall prevention algorithm using an acceleration sensor has been developed, and research is being conducted to enable continuous monitoring using a Holter electrocardiograph. In this study, we implemented a multi-input model that can detect and classify movements, including falls, utilizing the baroreflex characteristics of the heart’s potential energy changes due to movement, measured with an electrocardiogram with a three-axis acceleration sensor and a Holter electrocardiograph. Patterns were identified from the various movement characteristics of acceleration sensor data using a deep learning model consisting of CNN-LSTM, and heart rate variability (HRV) data were analyzed using a wide learning model to provide additional weight values for fall classification. Finally, a multi-input model using wide and deep learning was proposed to enhance the accuracy of fall classification. The results show that the HRV increased in fall case except in two motion types, while it decreased when standing up from a chair, indicating the application of the baroreflex characteristics reflecting the heart’s potential energy. Compared to the classification model using conventional HRV and ACC, a higher accuracy was achieved in the multi-input model using ACC-HRV data, and a precision, recall, and F1 score of 0.91 was measured, indicating improved performance. This is expected to have a positive impact on fall prevention by improving the accuracy of fall classification in the elderly for 15 different movements. Full article
(This article belongs to the Section Biomedical Sensors)
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20 pages, 600 KB  
Article
Exploring Context Allows Us to Better Understand Physical Activity in People with and Without Parkinson’s Who Have Fallen: A Mixed Methods Study
by Katherine Baker, Julia Das, Lynn Rochester, Silvia Del Din and Jenni Naisby
Geriatrics 2025, 10(1), 8; https://doi.org/10.3390/geriatrics10010008 - 7 Jan 2025
Viewed by 1195
Abstract
Background: Falls are a frequent and serious problem for older adults, especially for those living with Parkinson’s. The relationship between falls and physical activity is complex, and people often restrict activity following a fall. Exercise is an important aspect of reducing further risk [...] Read more.
Background: Falls are a frequent and serious problem for older adults, especially for those living with Parkinson’s. The relationship between falls and physical activity is complex, and people often restrict activity following a fall. Exercise is an important aspect of reducing further risk of a fall and a key component of the management of Parkinson’s. The aim of this study was to understand the types of activity they are engaged in, the environments in which they take place, and the experience of people with and without Parkinson’s who have fallen. Method: Seventeen people with Parkinson’s and thirteen older adults who had experienced at least one fall in the previous year were recruited to this mixed methods study. Activity levels were captured over one week using accelerometers and body-worn cameras, allowing the type and location of activity to be recorded and analysed. This information informed an interview. Results: Findings showed that although both groups often achieved up to 10,000 steps per day, this was in very short bouts of activity. Sedentary activity, such as watching television, dominated the findings. Participants were aware of the benefits of being active but described many barriers to achieving the level of activity they would like to. Full article
(This article belongs to the Special Issue Physical Activity and Exercise in Older Adults)
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13 pages, 1294 KB  
Article
Numerical Analysis of the Cell Droplet Loading Process in Cell Printing
by Yankun Wang, Fagui Pang, Shushan Lai, Renye Cai, Chenxiang Lai, Zexin Yu, Yiwei Zhu, Min Wu, Heng Zhang and Chunyu Kong
Micromachines 2024, 15(11), 1335; https://doi.org/10.3390/mi15111335 - 31 Oct 2024
Cited by 1 | Viewed by 1115
Abstract
Cell printing is a promising technology in tissue engineering, with which the complex three-dimensional tissue constructs can be formed by sequentially printing the cells layer by layer. Though some cell printing experiments with commercial inkjet printers show the possibility of this idea, there [...] Read more.
Cell printing is a promising technology in tissue engineering, with which the complex three-dimensional tissue constructs can be formed by sequentially printing the cells layer by layer. Though some cell printing experiments with commercial inkjet printers show the possibility of this idea, there are some problems, such as cell damage due the mechanical impact during cell direct writing, which include two processes of cell ejection and cell landing. Cell damage observed during the bioprinting process is often simply attributed to interactions between cells and substrate. However, in reality, cell damage can also arise from complex mechanical effects caused by collisions between cell droplets during continuous printing processes. The objective of this research is to numerically simulate the collision effects between continuously printed cell droplets within the bioprinting process, with a particular focus on analyzing the consequent cell droplet deformation and stress distribution. The influence of gravity force was ignored, cell droplet landing was divided into four phases, the first phase is cell droplet free falling at a certain velocity; the second phase is the collision between the descending cell droplet and the pre-existing cell droplets that have been previously printed onto the substrate. This collision results in significant deformation of the cell membranes of both cell droplets in contact; the third phase is the cell droplet hitting a rigid body substrate; the fourth phase is the cell droplet being bounced. We conducted a qualitative analysis of the stress and strain of cell droplets during the cell printing process to evaluate the influence of different parameters on the printing effect. The results indicate that an increase in jet velocity leads to an increase in stress on cell droplets, thereby increasing the probability of cell damage. Adding cell droplet layers on the substrate can effectively reduce the impact force caused by collisions. Smaller droplets are more susceptible to rupture at higher velocities. These findings provide a scientific basis for optimizing cell printing parameters. Full article
(This article belongs to the Section B:Biology and Biomedicine)
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9 pages, 1848 KB  
Article
Exploring the Influence of BMI on Gait Metrics: A Comprehensive Analysis of Spatiotemporal Parameters and Stability Indicators
by Lianne Koinis, Monish Maharaj, Pragadesh Natarajan, R. Dineth Fonseka, Vinuja Fernando and Ralph J. Mobbs
Sensors 2024, 24(19), 6484; https://doi.org/10.3390/s24196484 - 9 Oct 2024
Cited by 1 | Viewed by 1834
Abstract
Background: Gait analysis is a vital tool for evaluating overall health and predicting outcomes such as mortality and cognitive decline. This study explores how normal and obese BMI categories impact gait dynamics, addressing gaps in understanding the effect of body composition on specific [...] Read more.
Background: Gait analysis is a vital tool for evaluating overall health and predicting outcomes such as mortality and cognitive decline. This study explores how normal and obese BMI categories impact gait dynamics, addressing gaps in understanding the effect of body composition on specific gait parameters. Research Question: The primary objective is to investigate differences in spatiotemporal gait parameters—specifically, gait speed, step length, cadence, and double support time—between normal and obese BMI groups to understand the effects of obesity on gait. Methods: This observational case-control study analyzed spatiotemporal gait metrics from 163 participants, using inertial measurement units (IMUs) to collect data on various gait parameters. Statistical analyses explored the relationship between BMI categories and these metrics. Results: No significant differences were found in gait speed, cadence, stride duration, or double support time between the normal and obese groups. However, significant differences were identified in age, hypertension prevalence, balance problems, and the incidence of falls, emphasizing the complex effects of obesity on factors influencing gait stability. Significance: This study contributes to our understanding of obesity’s impact on gait by highlighting the need to consider associated health and stability parameters. These findings prompt a re-evaluation of how BMI is integrated into clinical gait assessments and emphasize the necessity for personalized healthcare strategies. This research highlights the importance of future studies with larger, more diverse populations and a wider array of biomechanical measures to dissect the relationship between BMI, body composition, and gait dynamics. Full article
(This article belongs to the Special Issue Wearable and Mobile Sensors and Data Processing—2nd Edition)
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12 pages, 222 KB  
Article
Evaluation of Prenatal Comfort, Sleep, and Quality of Life in Pregnant Women with Cholestasis: A Cross-Sectional Study
by Yeşim Yeşil, Ülkin Gündüz, Ayşegül Dönmez and Semir Paşa
Healthcare 2024, 12(14), 1399; https://doi.org/10.3390/healthcare12141399 - 13 Jul 2024
Cited by 1 | Viewed by 1686
Abstract
Background: Associated with adverse pregnancy outcomes, intrahepatic cholestasis of pregnancy is the most prevalent liver disease that women typically experience during pregnancy. This study aimed to evaluate prenatal comfort, sleep, and quality of life in pregnant women with cholestasis. Methods: This cross-sectional study [...] Read more.
Background: Associated with adverse pregnancy outcomes, intrahepatic cholestasis of pregnancy is the most prevalent liver disease that women typically experience during pregnancy. This study aimed to evaluate prenatal comfort, sleep, and quality of life in pregnant women with cholestasis. Methods: This cross-sectional study was implemented between November 2022 and June 2023 at Mardin Training and Research Hospital with 150 pregnant women who received a diagnosis of pregnancy-induced intrahepatic cholestasis and agreed to participate. The following tools were utilized to collect data: A personal information form exploring socio-demographic and obstetric characteristics of participants, the Prenatal Comfort Scale (PCS), the Pittsburgh Sleep Quality Index (PSQI), and the World Health Organization Quality of Life-Brief Form (WHOQOL-BREF). Results: The mean age of participants was 27.79 ± 6.33 years. The mean PCS and PSQI scores were 61.20 ± 5.84 and 9.52 ± 3.02, respectively. The mean scores of “physical health, psychological health, social relationships, and environmental health” sub-dimensions in WHOQOL-BREF were 10.63 ± 2.18, 10.48 ± 2.10, 11.31 ± 3.28, and 11.27 ± 2.10, respectively. A significant difference was found for PSQI regarding hospitalization status and change in sleep quality variables (p = 0.025 and p = 0.035, respectively). Conclusions: Cholestasis of pregnancy creates problems such as pruritus, body image changes, hospitalization, and poor sleep quality in women. This study showed that pregnant women with cholestasis had low levels of sleep quality and quality of life, implying that cholestasis affects their sleep quality, prenatal comfort levels, and quality of life in general. In addition, it is seen that women with this problem do not want to fall pregnant again. Full article
(This article belongs to the Section Nursing)
26 pages, 8754 KB  
Article
Prediction of Health Status of Small-Tailed Cold Sheep Based on Improved BP Neural Network
by Wei Fan, Haixia Wang, Yun Hou, Hongwei Du, Haiyang Zhang, Jing Yang, Tingxia Li and Ding Han
Electronics 2024, 13(13), 2602; https://doi.org/10.3390/electronics13132602 - 2 Jul 2024
Cited by 1 | Viewed by 1593
Abstract
According to related research, different body temperatures, heart rates, and locomotor behaviors of small-tailed cold goats can represent the physical condition of the goats themselves and are used as direct evidence for evaluating the physical health status of small-tailed cold goats. In this [...] Read more.
According to related research, different body temperatures, heart rates, and locomotor behaviors of small-tailed cold goats can represent the physical condition of the goats themselves and are used as direct evidence for evaluating the physical health status of small-tailed cold goats. In this paper, we designed and tested a system for predicting the health status of small-tailed cold sheep based on wearable information monitoring technology. To test the system, sheep wearable devices were worn on 36 small-tailed cold sheep of different ages and inconsistent health conditions at different time points from May to October. A SLBAS-BP neural network model for predicting the health condition of small-tailed cold sheep was established using the collected and processed data, which overcame the problem that the traditional gradient descent method in the BP neural network is prone to fall into local optimization leading to insufficient prediction ability. The correct prediction rates of the improved BP neural network for the four health conditions of healthy, sub-healthy, fever, and disease were 98.4%, 94.5%, 90.4%, and 98.7%, respectively, and the average correct prediction rate of the four conditions was 5.8% higher than that before the improvement, reaching 95.2%. Full article
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11 pages, 4478 KB  
Article
The Royal Chapel of Pedro I of Castile in the Christianised Mosque of Seville
by Pablo Gumiel-Campos
Arts 2024, 13(3), 84; https://doi.org/10.3390/arts13030084 - 8 May 2024
Viewed by 1547
Abstract
Pedro I of Castile (1350–1369) founded a royal chapel in the Christianised Mosque of Seville. He intended to house there his body, that of Queen María de Padilla, and their son the Infant Alfonso (1359–1362). This mausoleum is well documented both in the [...] Read more.
Pedro I of Castile (1350–1369) founded a royal chapel in the Christianised Mosque of Seville. He intended to house there his body, that of Queen María de Padilla, and their son the Infant Alfonso (1359–1362). This mausoleum is well documented both in the king’s will and in the chronicles of López de Ayala; however, there are no material remains as it was demolished with the construction of the new cathedral in the 15th century. In this article, we seek to produce a state of the art history of the building, a compilation of all the documentary sources that exist for its analysis, and an approach to the problems that hinder its study. We have also tried, unsuccessfully, to put forward a hypothesis about its original location, but we have come up against a dead end. Despite this, we consider it essential to lay all the cards on the table and prevent the mausoleum from falling into oblivion. Full article
(This article belongs to the Special Issue History of Medieval Art)
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9 pages, 6626 KB  
Case Report
Dramatic Wound Closing Effect of a Single Application of an iBTA-Induced Autologous Biosheet on Severe Diabetic Foot Ulcers Involving the Heel Area
by Ryuji Higashita, Yasuhide Nakayama, Manami Miyazaki, Yoko Yokawa, Ryosuke Iwai and Marina Funayama-Iwai
Bioengineering 2024, 11(5), 462; https://doi.org/10.3390/bioengineering11050462 - 6 May 2024
Cited by 1 | Viewed by 2326
Abstract
Introduction: Chronic wounds caused by diabetes or lower-extremity artery disease are intractable because the wound healing mechanism becomes ineffective due to the poor environment of the wound bed. Biosheets obtained using in-body tissue architecture (iBTA) are collagen-based membranous tissue created within the body [...] Read more.
Introduction: Chronic wounds caused by diabetes or lower-extremity artery disease are intractable because the wound healing mechanism becomes ineffective due to the poor environment of the wound bed. Biosheets obtained using in-body tissue architecture (iBTA) are collagen-based membranous tissue created within the body and which autologously contain various growth factors and somatic stem cells including SSEA4-posituve cells. When applied to a wound, granulation formation can be promoted and epithelialization may even be achieved. Herein, we report our clinical treatment experience with seven cases of intractable diabetic foot ulcers. Cases: Seven patients, from 46 to 93 years old, had large foot ulcers including in the heel area, which were failing to heal with standard wound treatment. Methods: Two or four Biosheet-forming molds were embedded subcutaneously in the chest or abdomen, and after 3 to 6 weeks, the molds were removed. Biosheets that formed inside the mold were obtained and applied directly to the wound surface. Results: In all cases, there were no problems with the mold’s embedding and removal procedures, and Biosheets were formed without any infection or inflammation during the embedding period. The Biosheets were simply applied to the wounds, and in all cases they adhered within one week, did not fall off, and became integrated with the wound surface. Complete wound closure was achieved within 8 weeks in two cases and within 5 months in two cases. One patient was lost due to infective endocarditis from septic colitis. One case required lower leg amputation due to wound recurrence, and one case achieved wound reduction and wound healing in approximately 9 months. Conclusions: Biosheets obtained via iBTA promoted wound healing and were extremely useful for intractable diabetic foot ulcers involving the heel area. Full article
(This article belongs to the Section Regenerative Engineering)
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15 pages, 2804 KB  
Article
Predicting the Effect of the Loading Rate on the Fracture Toughness of Hydraulic Asphalt Concrete Based on the Weibull Distribution
by Jianxin He, Xinyu Ding, Wu Yang, Haihua Yang and Liang Liu
Materials 2024, 17(4), 803; https://doi.org/10.3390/ma17040803 - 7 Feb 2024
Cited by 6 | Viewed by 1321
Abstract
The cracking problem of asphalt concrete panels is a crucial consideration in the design of hydraulic asphalt concrete seepage control bodies. Panels experiencing uneven rises or falls of water levels during impoundment may exhibit loading rate effects. Investigating the fracture toughness value of [...] Read more.
The cracking problem of asphalt concrete panels is a crucial consideration in the design of hydraulic asphalt concrete seepage control bodies. Panels experiencing uneven rises or falls of water levels during impoundment may exhibit loading rate effects. Investigating the fracture toughness value of asphalt concrete under varying loading rates is essential. This study employs a statistical method to calculate the fracture index KIC, using the semi-circular bending test (SCB) to examine the effect of loading rates on the Type I fracture mode of hydraulic asphalt concrete. The data are analyzed using the two-parameter Weibull distribution curve, offering insights into the minimum number of KIC test specimens. The results indicate an increase in KIC with loading rate, with greater data dispersion at faster rates. The Weibull distribution curve successfully fits the fracture behavior under different loading rates, providing valuable predictions. This study estimates the minimum number of SCB test specimens to be nine, based on a confidence level of 0.95 and a relative deviation not exceeding 5%. Full article
(This article belongs to the Section Construction and Building Materials)
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15 pages, 7010 KB  
Article
Numerical Simulation Research on Aerodynamic Characteristics during Take-Off Phase in Ski Jumping
by Qi Hu, Weidi Tang and Yu Liu
Appl. Sci. 2024, 14(3), 1221; https://doi.org/10.3390/app14031221 - 1 Feb 2024
Cited by 1 | Viewed by 1662
Abstract
In view of the inability to directly and accurately obtain an athlete’s aerodynamic force during the take-off phase through the wind tunnel test, the athlete’s aerodynamic force and surrounding flow field form under different take-off postures are obtained through numerical simulation research, and [...] Read more.
In view of the inability to directly and accurately obtain an athlete’s aerodynamic force during the take-off phase through the wind tunnel test, the athlete’s aerodynamic force and surrounding flow field form under different take-off postures are obtained through numerical simulation research, and the effects of different take-off modes on the aerodynamic characteristics during take-off in ski jumping are discussed. The multi-body system composed of the athlete and skis was selected as the research object. By using a partially averaged Navier–Stokes (PANS) turbulence model and a 3D numerical simulation of computational fluid dynamics (CFD), the aerodynamic characteristics of the athlete under different take-off postures were predicted. The take-off modes include the knee-push-hip (KPH) mode and hip-drive-knee (HDK) mode, and the hip joint angle of the HDK mode is significantly greater than that of the KPH mode. First, the aerodynamic force ratio of the athlete’s torso and legs is obviously large. Although the aerodynamic forces of arms themselves are not obvious, they have a great impact on the overall aerodynamic characteristics of the athlete, so the posture of the arms cannot be ignored. The total drag and moment of the HDK mode are significantly higher than that of the KPH mode, and the lift-to-drag ratio of the HDK mode is significantly lower than that of the KPH mode. At first, the total lift of the HDK mode is higher than that of the KPH mode, but in the last attitude, the total lift of the HDK mode does not rise but fall, and finally, the total lift of the HDK mode is lower than that of the KPH mode. The aerodynamic characteristics change dramatically during the take-off phase, and the aerodynamic characteristics of the two take-off modes are quite different, and these changes and differences are difficult to observe during real training and at the competition site. The KPH mode has an obvious aerodynamic advantage over the HDK mode. During the take-off process, the athlete should increase the force generated by the knee joint extension and appropriately reduce the speed of the hip joint extension, control the using force order of the lower limb joints, and push the hip joint extension by the knee joint extension in order to avoid issues, such as the hip joint angle being too large, the hip joint extension angle being too fast, the center of gravity being too far back, and other problems. Studying the aerodynamic characteristics during the take-off phase provides valuable insights for athletes to achieve favorable flight postures after take-off, offering scientific guidance to improve their training strategies and enhance their competitive performance. Full article
(This article belongs to the Special Issue Applied Biomechanics: Sport Performance and Injury Prevention III)
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19 pages, 973 KB  
Review
Recent Advances and Applications of Textile Technology in Patient Monitoring
by Lindsay Stern and Atena Roshan Fekr
Healthcare 2023, 11(23), 3066; https://doi.org/10.3390/healthcare11233066 - 29 Nov 2023
Cited by 4 | Viewed by 2284
Abstract
Sleep monitoring has become a prevalent area of research where body position and physiological data, such as heart rate and respiratory rate, are monitored. Numerous critical health problems are associated with poor sleep, such as pressure sore development, sleep disorders, and low sleep [...] Read more.
Sleep monitoring has become a prevalent area of research where body position and physiological data, such as heart rate and respiratory rate, are monitored. Numerous critical health problems are associated with poor sleep, such as pressure sore development, sleep disorders, and low sleep quality, which can lead to an increased risk of falls, cardiovascular diseases, and obesity. Current monitoring systems can be costly, laborious, and taxing on hospital resources. This paper reviews the most recent solutions for contactless textile technology in the form of bed sheets or mats to monitor body positions, vital signs, and sleep, both commercially and in the literature. This paper is organized into four categories: body position and movement monitoring, physiological monitoring, sleep monitoring, and commercial products. A detailed performance evaluation was carried out, considering the detection accuracy as well as the sensor types and algorithms used. The areas that need further research and the challenges for each category are discussed in detail. Full article
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