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Search Results (634)

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Keywords = Zoom

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16 pages, 2562 KiB  
Article
Harmonic and Interharmonic Measurement Method Using Two-Fold Compound Convolution Windows and Zoom Fast Fourier Transform
by Xiangui Xiao, Lei Zhao, Shengjun Zhou, Haijun Liu, Zhong Fu and Dan Hu
Energies 2025, 18(15), 4047; https://doi.org/10.3390/en18154047 - 30 Jul 2025
Viewed by 183
Abstract
With the rapidly increasing penetration of new energy resources, the power grid faces significant threats from harmonics. To measure and suppress these harmonics, numerous harmonic measurement methods have been proposed. However, accurately identifying the parameters of harmonics and interharmonics remains challenging. To address [...] Read more.
With the rapidly increasing penetration of new energy resources, the power grid faces significant threats from harmonics. To measure and suppress these harmonics, numerous harmonic measurement methods have been proposed. However, accurately identifying the parameters of harmonics and interharmonics remains challenging. To address this issue, we propose a new method that combines two-fold convolution windows and ZoomFFT. This method leverages the advantages of low side lobe peaks and high side lobe attenuation rates of compound convolution windows to suppress spectral leakage. Additionally, a six-spectral-line interpolation method is employed to correct the calculation results. Furthermore, ZoomFFT is utilized to locally amplify the spectrum, enabling the distinction between interharmonics and harmonics with closely spaced frequencies. The simulation results demonstrate that the proposed algorithm effectively identifies interharmonics with similar frequencies, outperforming single-window functions and ZoomFFT in terms of accuracy. Full article
(This article belongs to the Section F: Electrical Engineering)
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18 pages, 1132 KiB  
Article
A Longitudinal Study of Premalignant Gastric Lesions and Early Onset Gastric Cancer Among Young Adults in Central Saudi Arabia
by Ahmed Albadrani, Georgios Zacharakis, Mohammed Saad Alqahtani, Abdulrahman AlHarbi, Abdulaziz Alkudam, Abdullah Bawazir, Naif Albulayhid, Majed Zaki Bahader, Ahmed Mohammed Alghayyamah and Zahraa Saeed Alzaher
Curr. Oncol. 2025, 32(8), 428; https://doi.org/10.3390/curroncol32080428 - 30 Jul 2025
Viewed by 240
Abstract
Gastric cancer traditionally affects older adults, and its precursor lesions and risk factors are well-documented in this population. Helicobacter pylori (H. pylori) infection remains highly prevalent in Saudi Arabia and contributes to gastric pathology. However, early-onset gastric cancer (EOGC), diagnosed in [...] Read more.
Gastric cancer traditionally affects older adults, and its precursor lesions and risk factors are well-documented in this population. Helicobacter pylori (H. pylori) infection remains highly prevalent in Saudi Arabia and contributes to gastric pathology. However, early-onset gastric cancer (EOGC), diagnosed in individuals aged ≤ 45 years, presents unique challenges and remains poorly understood in young populations. Therefore, we conducted an observational cohort study using a prospective longitudinal design (2021–2024) involving 1823 Saudi nationals aged 18–45 years who underwent zoom high-definition chromoendoscopy to evaluate the prevalence of premalignant gastric lesions (PGLs) and EOGC. We found a high H. pylori prevalence (78.0%) with PGLs in 1.9% of participants and EOGC-adenocarcinoma in 0.7% of patients. All EOGC cases arose from dysplasia, with most PGLs being classified as OLGA/OLGIM stage II/III. Multiple risk factorswere significantly associated with PGLs and EOGC, including H. pylori infection (p = 0.022), increasing age (p < 0.001), a family history of gastric cancer (p < 0.001), poor dietary habits (p < 0.001), obesity (p < 0.001), and smoking (p < 0.001). Additional EOGC risk factors include dage of 36–45 years (p = 0.018), EBV infection (p = 0.016), and diabetes mellitus (p = 0.001). These findings demonstrate the notable presence of PGLs and EOGC in young Saudi adults and emphasize the importance of early detection and risk factor management in this vulnerable population. Full article
(This article belongs to the Section Gastrointestinal Oncology)
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23 pages, 3689 KiB  
Article
An Innovative Medical Image Analyzer Incorporating Fuzzy Approaches to Support Medical Decision-Making
by Cristina Ticala, Camelia M. Pintea, Mihaela Chira and Oliviu Matei
Med. Sci. 2025, 13(3), 97; https://doi.org/10.3390/medsci13030097 - 24 Jul 2025
Viewed by 340
Abstract
Background/Objectives: This paper presents a medical image analysis application designed to facilitate advanced edge detection and fuzzy processing techniques within an intuitive, modular graphical user interface. Methods: Key functionalities include classical edge detection, Ant Colony Optimization (ACO)-based edge extraction, and fuzzy edge generation, [...] Read more.
Background/Objectives: This paper presents a medical image analysis application designed to facilitate advanced edge detection and fuzzy processing techniques within an intuitive, modular graphical user interface. Methods: Key functionalities include classical edge detection, Ant Colony Optimization (ACO)-based edge extraction, and fuzzy edge generation, which offer improved boundary representation in images where uncertainty and soft transitions are prevalent. Results: One of the main novelties in contrast to the initial innovative Medical Image Analyzer, iMIA, is the fact that the system includes fuzzy C-means clustering to support tissue classification and unsupervised segmentation based on pixel intensity distribution. The application also features an interactive zooming and panning module with the option to overlay edge detection results. As another novelty, fuzzy performance metrics were added, including fuzzy false negatives, fuzzy false positives, fuzzy true positives, and the fuzzy index, offering a more comprehensive and uncertainty-aware evaluation of edge detection accuracy. Conclusions: The application executable file is provided at no cost for the purposes of evaluation and testing. Full article
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25 pages, 624 KiB  
Article
Development of a Specialized Telemedicine Protocol for Cognitive Disorders: The TeleCogNition Project in Greece
by Efthalia Angelopoulou, Ioannis Stamelos, Evangelia Smaragdaki, Kalliopi Vourou, Evangelia Stanitsa, Dionysia Kontaxopoulou, Christos Koros, John Papatriantafyllou, Vasiliki Zilidou, Evangelia Romanopoulou, Efstratia-Maria Georgopoulou, Paraskevi Sakka, Haralampos Karanikas, Leonidas Stefanis, Panagiotis Bamidis and Sokratis Papageorgiou
Geriatrics 2025, 10(4), 94; https://doi.org/10.3390/geriatrics10040094 - 16 Jul 2025
Viewed by 1130
Abstract
Background/Objectives: Access to specialized care for patients with cognitive impairment in remote areas is often limited. Despite the increasing adoption of telemedicine, standardized guidelines have not yet been specified. This study aimed to develop a comprehensive protocol for the specialized neurological, neuropsychological, and [...] Read more.
Background/Objectives: Access to specialized care for patients with cognitive impairment in remote areas is often limited. Despite the increasing adoption of telemedicine, standardized guidelines have not yet been specified. This study aimed to develop a comprehensive protocol for the specialized neurological, neuropsychological, and neuropsychiatric assessment of patients with cognitive disorders in remote areas through telemedicine. Methods: We analyzed data from (i) a comprehensive literature review of the existing recommendations, reliability studies, and telemedicine models for cognitive disorders, (ii) insights from a three-year experience of a specialized telemedicine outpatient clinic for cognitive movement disorders in Greece, and (iii) suggestions coming from dementia specialists experienced in telemedicine (neurologists, neuropsychologists, psychiatrists) who took part in three focus groups. A critical synthesis of the findings was performed in the end. Results: The final protocol included: technical and organizational requirements (e.g., a high-resolution screen and a camera with zoom, room dimensions adequate for gait assessment, a noise-canceling microphone); medical history; neurological, neuropsychiatric, and neuropsychological assessment adapted to videoconferencing; ethical–legal aspects (e.g., data security, privacy, informed consent); clinician–patient interaction (e.g., empathy, eye contact); diagnostic work-up; linkage to other services (e.g., tele-psychoeducation, caregiver support); and instructions for treatment and follow-up. Conclusions: This protocol is expected to serve as an example of good clinical practice and a source for official telemedicine guidelines for cognitive disorders. Ultimate outcomes include the potential enhanced access to specialized care, minimized financial and logistical costs, and the provision of a standardized, effective model for the remote diagnosis, treatment, and follow-up. This model could be applied not only in Greece, but also in other countries with similar healthcare systems and populations living in remote, difficult-to-access areas. Full article
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11 pages, 1439 KiB  
Article
“There’s a Difference Between Staying a Catholic and Being a Catholic”: Gathering Student Voice in Creating a Meaning-Full RE Curriculum for Catholic Schools
by Colin MacLeod
Religions 2025, 16(7), 887; https://doi.org/10.3390/rel16070887 - 10 Jul 2025
Viewed by 268
Abstract
This article examines how student voice informed the development of Tō Tātou Whakapono Our Faith, the national Religious Education (RE) curriculum for Catholic schools in Aotearoa, New Zealand. Through student-submitted RE questions and 63 informal Zoom-based “Interschool Catholic Yarns” with over 400 [...] Read more.
This article examines how student voice informed the development of Tō Tātou Whakapono Our Faith, the national Religious Education (RE) curriculum for Catholic schools in Aotearoa, New Zealand. Through student-submitted RE questions and 63 informal Zoom-based “Interschool Catholic Yarns” with over 400 senior students over several years, the National Centre for Religious Studies gathered valuable insights into student experience and expectations. These contributions influenced RE curriculum content, nuance, and priorities. Emphasising accessible engagement with young people, the two outlined approaches align with Catholic commitments to synodality and formation. This article demonstrates that engaging student voice is both possible and necessary in designing RE that is meaningful, faithful, and grounded. Full article
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10 pages, 194 KiB  
Article
Evaluation of a Pilot Program to Increase Mental Health Care Access for Youth—The Interprofessional Child-Centered Integrated Care (ICX2) Model
by Nicole Klaus, Evelyn English, Elizabeth Lewis, Jordan Camp, Sarah Krogman and Kari Harris
Children 2025, 12(7), 910; https://doi.org/10.3390/children12070910 - 10 Jul 2025
Viewed by 270
Abstract
Background/Objectives: The pediatric mental health crisis in the United States has reached unprecedented levels. Severe shortages in specialized health care professionals, particularly child and adolescent psychiatrists (CAPs), exacerbate the challenge of delivering timely and quality mental health care, especially in rural areas like [...] Read more.
Background/Objectives: The pediatric mental health crisis in the United States has reached unprecedented levels. Severe shortages in specialized health care professionals, particularly child and adolescent psychiatrists (CAPs), exacerbate the challenge of delivering timely and quality mental health care, especially in rural areas like Kansas. Innovative models such as Pediatric Mental Health Care Access (PMHCA) programs and School-Based Health Clinics (SBHCs) aim to integrate mental health expertise into primary care settings to address this gap. Methods: This paper examines an integrated care model to support SBHCs developed by the Kansas PMHCA. The Interprofessional Child-Centered Integrated Care Model (ICX2) was implemented within an SBHC in Haysville, KS. ICX2 utilizes biweekly collaborative team meetings (CTMs) via zoom involving primary care, psychology, child psychiatry, social work, and school resource coordinators to discuss patient cases and enhance the primary care management of pediatric mental health. This descriptive study analyzes data from January 2023 to June 2023, focusing on patient demographics, case characteristics discussed during CTMs, and recommendations made by the interprofessional team. Results: Findings illustrate the complex biopsychosocial needs of patients seen and define themes of case consultation and recommendations. Conclusions: Integrated care programs like ICX2 can be feasibly implemented through PMHCA programs and may be an efficient intervention to bridge resource gaps. Full article
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20 pages, 293 KiB  
Article
Perceived Barriers, Facilitators, and Needs Related to Promoting Physical Activity in Cancer Care: Qualitative Insights from Oncology Care Providers
by Gaurav Kumar, Priyanka Chaudhary, Apar Kishor Ganti, Jungyoon Kim, Lynette M. Smith and Dejun Su
Cancers 2025, 17(14), 2281; https://doi.org/10.3390/cancers17142281 - 9 Jul 2025
Viewed by 447
Abstract
Background: Physical activity (PA) is associated with lower mortality and cancer recurrence risks. Although evidence shows health benefits for cancer patients before, during, and immediately after treatment, PA recommendations are not regularly included in the standard care. Objective: The study aimed to identify [...] Read more.
Background: Physical activity (PA) is associated with lower mortality and cancer recurrence risks. Although evidence shows health benefits for cancer patients before, during, and immediately after treatment, PA recommendations are not regularly included in the standard care. Objective: The study aimed to identify perceived knowledge, barriers, and facilitators of oncology providers’ PA promotion for cancer patients using the 5A (Assess, Advise, Agree, Assist, and Arrange) framework. Methods: A qualitative research design with a phenomenological approach was adopted. A purposive sample of 16 oncology care providers in Nebraska participated in semi-structured interviews via Zoom/phone. Interviews were audio-recorded, transcribed, and imported into MAXQDA 2024 for thematic analysis. Results: Analysis of the qualitative data identified five themes: (i) Broad and inclusive conceptualizations of PA among oncology care providers suggested that they were able to define PA; (ii) Current Practices in PA Counseling included advising on PA and assessment; (iii) Barriers to PA counseling included lack of guideline awareness, insufficient training, low prioritization, uncertainty about responsibility, time constraints, limited resources, lack of referral systems, patient health conditions, and environmental factors; (iv) Facilitators were identified as acknowledged health benefits for cancer survivors, awareness of PA recommendations, access to community resources, and support from interdisciplinary teams; and (v) Expressed desire among oncology care providers for training on incorporating PA into oncology care. Conclusions: Oncology providers recognized PA’s health benefits for cancer survivors but did not promote it due to inadequate knowledge of guidelines and lack of resources. These barriers require improved PA counselling education to help providers incorporate PA into clinical care. Full article
(This article belongs to the Special Issue Disparities in Cancer Prevention, Screening, Diagnosis and Management)
16 pages, 272 KiB  
Article
Nurturing Healthy Smiles: Brazilian Immigrant Parents’ Perceptions and Parenting Practices of Healthy Eating to Promote Oral Health in Preschool-Aged Children: A Qualitative Study
by Ana Cristina Lindsay, Maria Gabriela Miranda Fontenele, Adriana Bento, Steven A. Cohen, Mary L. Greaney and Denise Lima Nogueira
Children 2025, 12(7), 896; https://doi.org/10.3390/children12070896 - 7 Jul 2025
Viewed by 346
Abstract
Background/Objectives: Oral health (OH) in early childhood is a key determinant of long-term well-being, shaped by parenting-related dietary and hygiene habits. While these influences are well-documented, they remain underexplored among Brazilian immigrant families in the United States (U.S.). Therefore, this study was designed [...] Read more.
Background/Objectives: Oral health (OH) in early childhood is a key determinant of long-term well-being, shaped by parenting-related dietary and hygiene habits. While these influences are well-documented, they remain underexplored among Brazilian immigrant families in the United States (U.S.). Therefore, this study was designed to examine how Brazilian immigrant parents’ perceptions and practices regarding diet and oral hygiene affect their preschool-aged children’s OH. Methods: This qualitative study consisted of in-depth interviews with Brazilian immigrant parents of preschool-aged children (ages 2–5) living in the U.S. Individual, in-depth interviews were conducted via Zoom, recorded, and transcribed in Brazilian Portuguese. Two native Brazilian researchers experienced in qualitative methods conducted a thematic analysis of the transcripts in Brazilian Portuguese using MAXQDA, a qualitative data analysis software. The analysis focused on identifying key perceptions, parenting practices, and barriers related to children’s diet and OH. Results: Parents strongly associated sugary foods with poor OH, identifying sugar as a major contributor to dental issues. Both mothers and fathers reported limiting sugar intake and encouraging good oral hygiene practices. While parents prioritized educating their children on healthy habits, barriers such as time constraints, reliance on external childcare, and economic limitations affected the consistent implementation of strategies. Conclusions: Brazilian immigrant parents understand the importance of diet and oral hygiene in in supporting their children’s early OH but face barriers in broader social contexts, such as daycare, preschools, and communities. Interventions should aim to support parents in their caregiving roles while simultaneously addressing systemic and environmental obstacles. Public health efforts should account for cultural, economic, and contextual factors to more effectively support Brazilian immigrant families in promoting their children’s OH. Full article
19 pages, 2567 KiB  
Article
Automated Video Quality Assessment for the Edinburgh Visual Gait Score (EVGS)
by Rajkumar Arumugam Jeeva, Edward D. Lemaire, Ramiro Olleac, Kevin Cheung, Albert Tu and Natalie Baddour
Methods Protoc. 2025, 8(4), 71; https://doi.org/10.3390/mps8040071 - 3 Jul 2025
Viewed by 296
Abstract
This research addresses critical challenges in clinical gait analysis by developing an automated video quality assessment framework to support Edinburgh Visual Gait Score (EVGS) scoring. The proposed methodology uses the MoveNet Lightning pose estimation model to extract body keypoints from video frames, enabling [...] Read more.
This research addresses critical challenges in clinical gait analysis by developing an automated video quality assessment framework to support Edinburgh Visual Gait Score (EVGS) scoring. The proposed methodology uses the MoveNet Lightning pose estimation model to extract body keypoints from video frames, enabling detection of multiple persons, tracking the person of interest, assessment of plane orientation, identification of overlapping individuals, detection of zoom artifacts, and evaluation of video resolution. These components are integrated into a unified quality classification system using a random forest classifier. The framework achieved high performance across key metrics, with 96% accuracy in detecting multiple persons, 95% in assessing overlaps, and 92% in identifying zoom events, culminating in an overall video quality categorization accuracy of 95%. This performance not only facilitates the automated selection of videos suitable for analysis but also provides specific video improvement suggestions when quality standards are not met. Consequently, the proposed system has the potential to streamline gait analysis workflows, reduce reliance on manual quality checks in clinical practice, and enable automated EVGS scoring by ensuring appropriate video quality as input to the gait scoring system. Full article
(This article belongs to the Section Biomedical Sciences and Physiology)
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15 pages, 388 KiB  
Article
Nurses’ Best Friend? The Lived Experiences of Nurses Who Utilized Dog Therapy in the Workplace
by Valerie A. Esposito Kubanick and Joy Z. Scharfman
Nurs. Rep. 2025, 15(7), 246; https://doi.org/10.3390/nursrep15070246 - 3 Jul 2025
Viewed by 659
Abstract
The aim of this work is to explore and understand the lived experience of nurses who chose to schedule visits with an Emotional Support Animal (ESA), i.e., a dog, during their working shift. Background/Objectives: Nursing practice is rigorous, weighted with intense responsibility that [...] Read more.
The aim of this work is to explore and understand the lived experience of nurses who chose to schedule visits with an Emotional Support Animal (ESA), i.e., a dog, during their working shift. Background/Objectives: Nursing practice is rigorous, weighted with intense responsibility that creates an environment conducive to stress and anxiety for the nurses, who have reported a higher level of work stress than other healthcare professionals. Knowing and addressing the factors impacting mental health/nurses’ well-being is crucial to providing care to patients. Stressful work environments result in burnout, compassion fatigue, depression, anxiety, suicide, and resignation. Understanding nurses’ perspectives on work related stress encourages hospitals to structure practices supporting nurses’ mental health and ability to provide quality care. Methods: A qualitative hermeneutic phenomenological approach was employed. Participants scheduled six weekly 10-min visits with Rex, a certified Service Dog for anxiety depression and PTSD, and registered ESA. A sample of 11 RNs participated in Rex visits at the workplace; field notes were taken during observations of visits. Semi-structured 30-min interviews conducted via Zoom, audio-recorded, and transcribed with NVivo were conducted. Results: Data were examined with Interpretative Phenomenological Analysis. Four main themes emerged: Preparing for the unknown, Doing the work, Refueling and resetting-Visits with Rex, What about nurses? Conclusions: This study highlights the need for nurses and hospital systems to incorporate self-care/self-reflection, including time/opportunities for nurses’ stress management during their practice. Knowledge of nurses receiving ESA interventions sheds light on how to protect/preserve the well-being of nurses practicing in this demanding profession. ESAs for nurses in the workplace offers an option to utilize dog therapy to re-energize and continue their shift renewed and refreshed. Full article
(This article belongs to the Section Mental Health Nursing)
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11 pages, 2074 KiB  
Article
The Influence of Filtration on the Results of Measurements Made with Optical Coordinate Systems
by Wiesław Zaborowski, Adam Gąska, Wiktor Harmatys and Jerzy A. Sładek
Appl. Sci. 2025, 15(13), 7475; https://doi.org/10.3390/app15137475 - 3 Jul 2025
Viewed by 260
Abstract
This article presents research and a discussion on the proper use of filtration in optical measurements. Measurements were taken using a Werth multisensory machine using a Werth Zoom optical sensor. During optical measurements, the filtration option can be used. The manufacturer defines filters [...] Read more.
This article presents research and a discussion on the proper use of filtration in optical measurements. Measurements were taken using a Werth multisensory machine using a Werth Zoom optical sensor. During optical measurements, the filtration option can be used. The manufacturer defines filters as “Dust”. They allow the machine operator to define the appropriate size depending on the type of inclusions or artifacts created in the production process. They can occur in processes such as punching on presses or production in the injection molding process of plastics. The presented research results and statistical analyses confirm the assumptions regarding the validity of using filters and their values. The use of filters with a higher value significantly affects the obtained results and forces the machine user to make a reasonable choice. Full article
(This article belongs to the Special Issue Advanced Studies in Coordinate Measuring Technique)
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20 pages, 1009 KiB  
Article
Digitalization of Higher Education: Students’ Perspectives
by Vojko Potocan, Zlatko Nedelko and Maja Rosi
Educ. Sci. 2025, 15(7), 847; https://doi.org/10.3390/educsci15070847 - 2 Jul 2025
Viewed by 340
Abstract
This study examines the use of digitalized educational solutions among students in higher education institutions (HEIs). Drawing upon theories of technology, digitalization, and education, we analyze the suitability of different digitalization solutions for students in HEIs. Educational organizations that apply different digitalized technologies [...] Read more.
This study examines the use of digitalized educational solutions among students in higher education institutions (HEIs). Drawing upon theories of technology, digitalization, and education, we analyze the suitability of different digitalization solutions for students in HEIs. Educational organizations that apply different digitalized technologies provide customizable platforms for authoring and disseminating multimedia-rich e-education and smart education. However, pedagogical practices indicate several gaps between the level of HEI digitalization achieved and its suitability for HEI participants. Thus, we analyze the state of various digitalized technologies in HEIs and their suitability for meeting students’ expectations. The results of our research show that students most highly rate modern educational methods such as practical learning supported by access to digitized materials via websites, social networks, and smartphones while assigning a lower rating to the use of classic education, supported by digital textbooks and traditional technologies such as Skype, Zoom, podcasts, and online videos. This study has several theoretical implications, among which is the need to further develop highly digitized materials and purpose-designed digitized solutions for individual areas and specific educational purposes. The practical implications indicate the need to expand the use of website networks, smartphones, and smart table solutions in modern educational practices in HEIs. Full article
(This article belongs to the Special Issue Unleashing the Potential of E-learning in Higher Education)
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15 pages, 4864 KiB  
Article
The Systematic Design of Voice Coil Motor Structures for Rapid Zoom Optical Lens
by Junqiang Gong, Dameng Liu and Jianbin Luo
Actuators 2025, 14(7), 332; https://doi.org/10.3390/act14070332 - 2 Jul 2025
Viewed by 287
Abstract
In order to solve the zoom delay issue for high-magnification zoom optical systems, a voice coil motor (VCM) is used to achieve rapid zooming. In this paper, the structural design of VCMs is systematically analyzed through magnetic field numerical computations. Firstly, finite element [...] Read more.
In order to solve the zoom delay issue for high-magnification zoom optical systems, a voice coil motor (VCM) is used to achieve rapid zooming. In this paper, the structural design of VCMs is systematically analyzed through magnetic field numerical computations. Firstly, finite element method (FEM) is used to analyze magnetic field of single magnets, and simulations correspond to experimental results. Both FEM and equivalent magnetic charge (EMC) results confirm that increasing magnet thickness while reducing its lateral dimensions will contribute to magnetic enhancement. Furthermore, the influence of structural parameters VCM is analyzed, validating the yoke’s critical role in suppressing edge effects and optimizing magnetic circuit efficiency, and optimal yoke thickness and magnet width range are determined. Moreover, a simple EMC calculation method is proposed for rapid and accurate determination of the magnetic field distribution in the VCM air gap. Optimal structural parameters of VCM are determined for a 40× rapid zoom lens with cost and space limitations. Driving force Fdrive = 5.58 N is about 5 times the demand force Fd = 1.06 N, and the prototype fabrication of the rapid zoom lens is successfully accomplished. Moving group reaches 35.4 mm destination within 0.18 s, and photographs confirm that the rapid zoom system achieves 100-ms-level short/long-focus transition. Rapid zoom lens shows great potential in applications including security surveillance, industrial visual inspection, and intelligent logistics management. Full article
(This article belongs to the Special Issue Actuators in 2025)
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24 pages, 16234 KiB  
Article
A Contrast-Enhanced Feature Reconstruction for Fixed PTZ Camera-Based Crack Recognition in Expressways
by Xuezhi Feng and Chunyan Shao
Electronics 2025, 14(13), 2617; https://doi.org/10.3390/electronics14132617 - 28 Jun 2025
Viewed by 168
Abstract
Efficient and accurate recognition of highway pavement cracks is crucial for the timely maintenance and long-term use of expressways. Among the existing crack acquisition methods, human-based approaches are inefficient, whereas carrier-based automated methods are expensive. Additionally, both methods present challenges related to traffic [...] Read more.
Efficient and accurate recognition of highway pavement cracks is crucial for the timely maintenance and long-term use of expressways. Among the existing crack acquisition methods, human-based approaches are inefficient, whereas carrier-based automated methods are expensive. Additionally, both methods present challenges related to traffic obstruction and safety risks. To address these challenges, we propose a fixed pan-tilt-zoom (PTZ) vision-based highway pavement crack recognition workflow. Pavement cracks often exhibit complex textures with blurred boundaries, low contrast, and discontinuous pixels, leading to missed and false detection. To mitigate these issues, we introduce an algorithm named contrast-enhanced feature reconstruction (CEFR), which consists of three parts: comparison-based pixel transformation, nonlinear stretching, and generating a saliency map. CEFR is an image pre-processing algorithm that enhances crack edges and establishes uniform inner-crack characteristics, thereby increasing the contrast between cracks and the background. Extensive experiments demonstrate that CEFR improves recognition performance, yielding increases of 3.1% in F1-score, 2.6% in mAP@0.5, and 4.6% in mAP@0.5:0.95, compared with the dataset without CEFR. The effectiveness and generalisability of CEFR are validated across multiple models, datasets, and tasks, confirming its applicability for highway maintenance engineering. Full article
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17 pages, 2737 KiB  
Article
Design of a Double-Sided Non-Displacement Telecentric Zoom Optical System Using Two Liquid Lens Groups
by Xiaogang Chen, Youping Huang and Hao Zhang
Photonics 2025, 12(7), 655; https://doi.org/10.3390/photonics12070655 - 28 Jun 2025
Viewed by 326
Abstract
A double-sided telecentric zoom optical system can ensure the measurement and detection accuracy for different workpiece sizes and plays a crucial role in industrial detection. The conventional double-sided telecentric mechanical zoom system is faced with the problem of complex structure and difficult focusing. [...] Read more.
A double-sided telecentric zoom optical system can ensure the measurement and detection accuracy for different workpiece sizes and plays a crucial role in industrial detection. The conventional double-sided telecentric mechanical zoom system is faced with the problem of complex structure and difficult focusing. To address these issues, a liquid lens is applied to design a non-displacement double-sided telecentric zoom system in this paper. Here, the design method of the conventional double telecentric zoom system is analyzed first; then, the liquid lenses are substituted for the mechanical motion groups. Finally, a double-sided telecentric zoom system with a detection range of 25~60 mm and a magnification of −0.44×~−0.183× has been designed and optimized by Zemax software. The design results show that in the process of magnification, the root mean square radius of the diffuse spot in the system is smaller than the pixel size during the process of zooming. The modulation transfer function values at the Nyquist frequency of 80 lp/mm are all above 0.4, distortion is controlled within 0.2, and telecentricity is less than 0.5°, indicating that the system has excellent imaging quality, low distortion, and high telecentric and other characteristics, which meet system requirements. The design method proposed in this paper can provide an effective solution for the rapid conversion of displacement zoom systems to non-displacement zoom systems. Full article
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