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13 pages, 896 KiB  
Article
One-Year Comparative Evaluation of Highly Aspherical Lenslets and Horizontally Asymmetric Peripheral Defocus Lenses for Myopia Control in School-Aged Children
by Ivana Orešković, Maja Malenica Ravlić, Lana Knežević, Blanka Doko Mandić, Goran Marić, Ante Vukojević, Mia Zorić Geber, Zoran Vatavuk, Ivan Sabol and Jelena Škunca Herman
Life 2025, 15(7), 1119; https://doi.org/10.3390/life15071119 - 17 Jul 2025
Viewed by 351
Abstract
Purpose: The aim of this study was to compare the one-year efficacy of three spectacle lens designs, highly aspherical lenslets (HALs), horizontally asymmetric peripheral defocus (HAPD) lenses, and standard single vision lenses (SVLs) in slowing myopia progression in school-aged children. Methods: In this [...] Read more.
Purpose: The aim of this study was to compare the one-year efficacy of three spectacle lens designs, highly aspherical lenslets (HALs), horizontally asymmetric peripheral defocus (HAPD) lenses, and standard single vision lenses (SVLs) in slowing myopia progression in school-aged children. Methods: In this prospective, non-randomized study, 57 children, aged 8–17 years, were grouped based on the type of lenses worn: HAL (n = 16), HAPD (n = 21), or SVL (n = 20). Comprehensive ophthalmologic examinations were performed at baseline, 6 months, and 12 months. Outcome measures included spherical equivalent refraction (SER), spherical refraction (SR), cylindrical refraction (CR), and axial length (AL). Data were analyzed using non-parametric tests with significance set at p < 0.05. Results: All groups showed some progression in SER and AL over 12 months. The HAL group demonstrated the smallest median SER change (−0.3 D), compared to HAPD (−0.5 D) and SVL (−0.4 D), though group differences were not statistically significant (p = 0.111). Axial elongation was significantly lower in the HAL group (0.1 mm, IQR: 0.0–0.2 mm) compared to HAPD and SVL (both 0.2 mm, p < 0.0001). CR remained stable in all groups, with no clinically meaningful changes. The HAPD groups showed no advantages over SVL in any parameter. Conclusions: Among the three lens types studied, HAL lenses were the most effective in reducing both refractive and axial myopia progression over 12 months. These findings support their use as a reliable intervention in pediatric myopia control. Full article
(This article belongs to the Section Physiology and Pathology)
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21 pages, 13994 KiB  
Article
Fine Structure and Optical Features of the Compound Eyes of Adult Female Ceratosolen gravelyi (Hymenoptera: Agaonidae)
by Hua Xie, Yan Shi, Shouxian Zhang, Yonghui Zhu, Subo Shao, Yuan Zhang, Pei Yang and Zongbo Li
Insects 2025, 16(7), 682; https://doi.org/10.3390/insects16070682 - 30 Jun 2025
Viewed by 701
Abstract
Pollinating fig wasps (Agaonidae) engage in an obligate mutualism with Ficus species, which is mediated by host-specific chemical cues. However, the role of visual perception in host recognition remains poorly understood, particularly because of a lack of structural studies of their compound eyes. [...] Read more.
Pollinating fig wasps (Agaonidae) engage in an obligate mutualism with Ficus species, which is mediated by host-specific chemical cues. However, the role of visual perception in host recognition remains poorly understood, particularly because of a lack of structural studies of their compound eyes. We investigated the ocular morphology of female Ceratosolen gravelyi (exclusive pollinator of F. semicordata) using scanning/transmission electron microscopy. The oval apposition eyes contain 228–263 ommatidia, which are asymmetrically distributed between the left and right eyes. Each ommatidium comprises a biconvex corneal lens overlying a tetrapartite eucone crystalline cone; proximal cone cells reveal an interlaced labyrinth. Pigment cells encapsulate each ommatidium, and numerous pigment granules and mitochondria are present in both pigment and retinular cells. Nine retinular cells comprise a unit, with eight photoreceptors (R1–R8) forming the rhabdom from the cone base to the basal matrix; a ninth cell replaces R8 in the apical third of the rhabdom. Optical metrics, including F-number (1.1°), acceptance angle (10.0°), and ommatidial sensitivity (0.26 µm2/sr), indicate diurnal activity in bright environments. These adaptations suggest that their eyes are critical for processing visual cues during host interactions, which advances our understanding of multimodal sensory integration in fig–wasp mutualism. Full article
(This article belongs to the Section Insect Physiology, Reproduction and Development)
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22 pages, 9215 KiB  
Article
Ensquared Energy and Optical Centroid Efficiency in Optical Sensors, Part 3: Optical Sensors
by Marija Strojnik and Yaujen Wang
Photonics 2025, 12(4), 344; https://doi.org/10.3390/photonics12040344 - 3 Apr 2025
Viewed by 355
Abstract
We previously introduced the concepts of optical centroid efficiency (OCE) and enclosed energy within a rectangular pixel (EOD). We applied them to an ideal lens with and without a central obscuration for two different detector pixel sizes. Also, we [...] Read more.
We previously introduced the concepts of optical centroid efficiency (OCE) and enclosed energy within a rectangular pixel (EOD). We applied them to an ideal lens with and without a central obscuration for two different detector pixel sizes. Also, we analyzed the performance of OCE vs. EOD for the following three Seidel primary aberrations of an ideal lens: spherical, coma, and astigmatism, plus defocus. In this paper, we concentrate on three different optical remote sensing instrument configurations. We burden them with a set of aberrations to mimic realistic generalized error budgets that cover potential ground, lunch, and on-orbit environmental conditions. The shape of the OCE vs. EOD curve depends to a large degree on the dominant aberration. With the proper choice of detector pixel size, OCE increases with EOD when EOD is larger than 0.6. The increased detector pixel size is advantageous for structures that enhance diffraction effects, and for off-axis and asymmetrical configurations. Analytical and experimental tests are proposed for original critical cases. Furthermore, OCE and EOD, as functional figures of merit, may be effectively applied to instruments for monitoring tumors and their evolution to cancerous tissue, leading to timely diagnosis. Full article
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11 pages, 2239 KiB  
Article
Relationship Between Ocular Trauma Score and Computed Tomography Findings in Eyes with Penetrating Globe Injuries: A Preliminary Study
by Berire Şeyma Durmuş Ece, Zübeyir Yozgat, Yusuf İnançlı, Bunyamin Ece and Sonay Aydin
Diagnostics 2025, 15(7), 830; https://doi.org/10.3390/diagnostics15070830 - 25 Mar 2025
Viewed by 510
Abstract
Background/Objectives: The aim of this study was to evaluate computed tomography (CT) findings in penetrating globe injuries and their relationship with ocular trauma scores (OTSs). Methods: Patients with penetrating globe injuries who had orbital CT images were included in this study. [...] Read more.
Background/Objectives: The aim of this study was to evaluate computed tomography (CT) findings in penetrating globe injuries and their relationship with ocular trauma scores (OTSs). Methods: Patients with penetrating globe injuries who had orbital CT images were included in this study. Demographics, injury zone, and ophthalmologic exam data were collected retrospectively. OTSs and categories were determined. Orbital CT images were evaluated by a radiologist to determine decreased globe volume, globe wall irregularity, chorioretinal layer thickening, lens dislocation, asymmetric anterior chamber depth (ACD), abnormal vitreous density, and intraocular air presence. Results: This study included 30 eyes of 30 patients. The majority of patients (n = 20, 66.7%) had Zone I injuries. The most common CT findings were globe wall irregularity (53.3%) and asymmetric ACD (53.3%). No CT findings were observed in 10 patients (33.3%). Globe wall irregularity was the most frequent CT finding in the OTS II category, while asymmetric ACD was most frequent in the OTS IV category. All patients with decreased globe volume, lens dislocation, abnormal vitreous density, and ≥3 CT findings were in the OTS II category. A significant negative correlation was found between the number of CT findings and OTS (r = −0.644, p < 0.001), and a significant positive correlation was found between the number of CT findings and clinically measured wound size (r = 0.600, p < 0.001). Conclusions: CT findings help assess ocular trauma severity, but clinical examination remains essential for accurate diagnosis. Full article
(This article belongs to the Special Issue Recent Advances in Computed Tomography Imaging for Clinical Diagnosis)
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2 pages, 155 KiB  
Correction
Correction: Sánchez-Tena et al. Effectiveness of a Spectacle Lens with a Specific Asymmetric Myopic Peripheral Defocus: 12-Month Results in a Spanish Population. Children 2024, 11, 177
by Miguel Ángel Sánchez-Tena, Jose Miguel Cleva, Cesar Villa-Collar, Marta Álvarez, Alicia Ruiz-Pomeda, Clara Martinez-Perez, Cristina Andreu-Vazquez, Eva Chamorro and Cristina Alvarez-Peregrina
Children 2025, 12(3), 311; https://doi.org/10.3390/children12030311 - 28 Feb 2025
Viewed by 497
Abstract
There was an error in the original publication for the abstract [...] Full article
17 pages, 6439 KiB  
Article
Performance Analysis of a Micro-Photovoltaic Concentrator Designed for Automotive Applications
by Salima El Ayane and Ali Ahaitouf
Energies 2024, 17(24), 6470; https://doi.org/10.3390/en17246470 - 23 Dec 2024
Viewed by 977
Abstract
This research paper delves into the potential use of solar energy as an alternative energy source for future vehicles. The study introduces a system that overcomes the limitations of traditional solar panels by achieving a reduced thickness of less than 35 mm, while [...] Read more.
This research paper delves into the potential use of solar energy as an alternative energy source for future vehicles. The study introduces a system that overcomes the limitations of traditional solar panels by achieving a reduced thickness of less than 35 mm, while acknowledging the challenges faced by vehicles, such as the inability to maintain a fixed orientation towards the sun and frequent shading from surrounding objects. To tackle these challenges, our system incorporates the design of an asymmetrical and extended polynomial lens and optimizes it to widen the acceptance angle of incident sunlight, enabling the solar panels to capture a wider range of solar radiation, even when the vehicle is not ideally aligned with the sun. The goal of this innovative design is not only to maximize energy output in urban conditions, ensuring efficient solar utilization despite shading challenges, but also to maintain a compact, lightweight structure suitable for installation on vehicle rooftops and competitive with ordinary PV panels. Additionally, our system is a tracking and heat spreader-free structure. This simple structure enables cheaper mass production and the lightweight nature of the structure results in affordable manufacturing and assembly processes. Through collaboration with micro-fabrication, macro-electronic industries, and micro-LED technologies, our system is a strong candidate for a low-cost, high-efficiency system. The results show an optical efficiency of around 52.53% for incident rays at a 45° angle, with the remaining rays captured by adjacent lenses resulting in a total optical efficiency around 76%. Full article
(This article belongs to the Section B: Energy and Environment)
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16 pages, 8564 KiB  
Article
A Study on Pendant and Blackboard Asymmetric Lens LED Luminaires for Optimal Illumination in Classrooms
by Duong Thi Giang, Pham Hong Duong, Nguyen Van Quan, Tran Ngoc Thanh Trang and Tran Quoc Khanh
Sustainability 2024, 16(22), 10015; https://doi.org/10.3390/su162210015 - 16 Nov 2024
Viewed by 1316
Abstract
This study examines the transformative impact of integrating pendant asymmetric lens (PAL) and blackboard asymmetric lens (BAL) LED luminaires to enhance classroom lighting, with the goals of replicating the ambient effects of natural daylight and promoting energy efficiency. This research focuses on improving [...] Read more.
This study examines the transformative impact of integrating pendant asymmetric lens (PAL) and blackboard asymmetric lens (BAL) LED luminaires to enhance classroom lighting, with the goals of replicating the ambient effects of natural daylight and promoting energy efficiency. This research focuses on improving the quality of learning environments through uniform, soft, and diffused lighting, which mimics sky-like illumination while adhering to sustainable energy practices. Advanced asymmetric lens LED luminaires are employed to achieve optimal lighting distribution, as indicated by luminous intensity distribution curves. Comparative analyses in diverse educational settings reveal significant improvements in ceiling illuminance, ranging from 935 to 1000 lx, and workspace illuminance from 660 to 720 lx, with reduced glare (UGR < 10). This results in bright, visually comfortable spaces conducive to learning. Additionally, the PAL and BAL solutions outperform conventional lighting systems like stretched ceilings and lightboxes by maintaining clear overhead spaces, eliminating shadows, and offering cost-effective solutions. This successful integration demonstrates a notable advancement in the development of energy-efficient, visually comfortable educational environments, contributing to the goals of sustainability and improved well-being for both students and teachers. Full article
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12 pages, 1913 KiB  
Article
Optical Bench Evaluation of a Novel, Hydrophobic, Acrylic, One-Piece, Polyfocal Intraocular Lens with a “Zig-Zag” L-Loop Haptic Design
by Andreas F. Borkenstein, Eva-Maria Borkenstein, Pooria Omidi and Achim Langenbucher
Vision 2024, 8(4), 66; https://doi.org/10.3390/vision8040066 - 14 Nov 2024
Cited by 1 | Viewed by 1285
Abstract
Purpose: The number of presbyopia-correcting (premium) intraocular lenses (IOLs) is growing steadily as the desire for spectacle independence after cataract surgery increases. The aim of this laboratory study was to evaluate a newly launched hydrophobic, acrylic, polyfocal, refractive intraocular lens with a new [...] Read more.
Purpose: The number of presbyopia-correcting (premium) intraocular lenses (IOLs) is growing steadily as the desire for spectacle independence after cataract surgery increases. The aim of this laboratory study was to evaluate a newly launched hydrophobic, acrylic, polyfocal, refractive intraocular lens with a new optical design and geometry. This polyfocal IOL has three different zones (within the optic) with radially asymmetric design. Methods: We performed optical bench tests to calculate the optical characteristics of the sample. The optical performance and quality of IOLs based on ISO 11979-2 and 11979-9 requirements were analyzed with the NIMO TR0815 (Lambda-X). In addition, optical quality metrics were evaluated with the IOLA MFD device (Rotlex). Sphere, Add, modulation transfer function (MTF), the energy distribution between the modes and the MTF along the whole range from far to near were analyzed. Results: The power histogram showed that the tested IOL has the characteristics of a polyfocal IOL with a wide range of optical power between 20.5 and 24.5 diopters. Two distinct peaks were observed, indicating bifocal functionality. In the radial and axial power surface map, all three zones, stated by the company, could be detected. Larger apertures lead to a significant increase in MTF at the far peak, indicating better visual acuity for distant objects under low-light conditions. It was observed that in small aperture sizes, intermediate vision seems to be dominant. The energy distribution remained almost constant with increasing aperture size. Conclusions: This laboratory study was able to confirm the properties of the polyfocal lens stated by the company. Three optical zones could be identified. However, further optical bench tests should be performed to evaluate the new lens under tilted and decentered conditions. Clinical studies have to confirm that the presbyopia-correcting, polyfocal lens can achieve good clinical results with high patient satisfaction without disturbing side effects. Full article
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15 pages, 8062 KiB  
Article
Exploring Asymmetric Lens–Total Internal Reflection (AL–TIR) Optics for Uniform Ceiling Illumination in Interior Lighting
by Duong Thi Giang, Pham Hong Duong and Tran Quoc Khanh
Appl. Sci. 2024, 14(21), 10081; https://doi.org/10.3390/app142110081 - 4 Nov 2024
Viewed by 1445
Abstract
This study presents a significant advancement in LED interior lighting through the development and application of Asymmetric Lens–Total Internal Reflection (AL–TIR) optics, with a focus on enhancing lighting uniformity and indoor comfort by simulating sky-like lighting distribution. AL–TIR technology employs asymmetric lenses combined [...] Read more.
This study presents a significant advancement in LED interior lighting through the development and application of Asymmetric Lens–Total Internal Reflection (AL–TIR) optics, with a focus on enhancing lighting uniformity and indoor comfort by simulating sky-like lighting distribution. AL–TIR technology employs asymmetric lenses combined with total internal reflection to efficiently redirect and spread light, achieving a controlled and even ceiling illumination suitable for various interior applications. This research explored the establishment of ideal luminous intensity curves, devised practical AL–TIR optical designs through numerical calculations, and conducted extensive simulations to assess performance in typical indoor environments. Our findings demonstrated substantial improvements in lighting uniformity, with the AL and AL–TIR systems achieving direct illuminance uniformities of 0.78 and 0.83, respectively, compared to traditional tube LEDs at 0.25. These results, validated in several office rooms, highlight the efficacy of AL–TIR optics in revolutionizing indoor lighting design by balancing optimal lighting distribution with occupant comfort and well-being. Full article
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12 pages, 5154 KiB  
Article
A Long-Range Lidar Optical Collimation System Based on a Shaped Laser Source
by Shanshan Feng, Yuanhui Mu, Luyin Liu, Ruzhang Liu, Enlin Cai and Shuying Wang
Appl. Sci. 2024, 14(21), 9662; https://doi.org/10.3390/app14219662 - 23 Oct 2024
Viewed by 1642
Abstract
Semiconductor near-infrared lasers have been widely used in lidar systems. However, various source types have different shapes and divergence angles, causing more difficulties for long-distance detection. In this paper, an optical collimation system is designed for a long-range lidar system with a shaped [...] Read more.
Semiconductor near-infrared lasers have been widely used in lidar systems. However, various source types have different shapes and divergence angles, causing more difficulties for long-distance detection. In this paper, an optical collimation system is designed for a long-range lidar system with a shaped laser source (the wavelength is 905 nm, the emitted spot size is 50 µm long by 10 µm wide, and the divergence angles are 33°and 15°, respectively, which are unconventional). On the basis of the traditional method of aspheric lens setting, a pair of asymmetric aspherical lenses were designed using an extended polynomial. The simulation results show that the spot shapes are all close to circular from 100 mm to 30 m and the spot size always remains the same value. The corrected optical system is put into the designed lidar system for verification. It results show that the average divergence angles in the long and short axis directions are 0.06°and 0.07°, which satisfy the project requirements. This optical system designed provides a collimation scheme and expands the application of vehicle-mounted lidar in the field of long-range detection. Full article
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14 pages, 267 KiB  
Article
A Spiritual Theology of Dialogue: Levinas, Burggraeve, and Catholic Theology
by Glenn Morrison
Religions 2024, 15(10), 1206; https://doi.org/10.3390/rel15101206 - 3 Oct 2024
Viewed by 1602
Abstract
Dialogue needs provocative interlocutors. Instilling a grave and shuddering awakening to the conscience, Emmanuel Levinas has provided a corpus of writings unveiling an immemorial horizon and divine calling of infinite responsibility before the other, the brother/sister stranger. Roger Burggraeve has animated Levinas’ writings [...] Read more.
Dialogue needs provocative interlocutors. Instilling a grave and shuddering awakening to the conscience, Emmanuel Levinas has provided a corpus of writings unveiling an immemorial horizon and divine calling of infinite responsibility before the other, the brother/sister stranger. Roger Burggraeve has animated Levinas’ writings within a Christian theological horizon as a source of formation in the service of promoting biblical wisdom and love in the life of faith. The writings of Pope Benedict XVI and Pope Francis together portray a Catholic theological gravity to bring dialogue into a spiritual, practical, and social domain. Accordingly, this article develops the notion of dialogue within a Jewish and Christian lens by introducing the sense of the non-reciprocal character of dialogue, an asymmetrical relation of responsibility to the other evidencing the preconditions of dialogue. Levinas’ notion of non-reciprocal dialogue, taken further by the writings of Burggraeve, reveals a pre-original affectivity or ‘dialogical’ character of interpersonal relations of commitment respecting the other’s mystery and unknowability. This means that the dialogical relation is a pathway of ethical transcendence, a holy ground evoking an integral human ecology of maternity and fraternity. Such covenantal alterity in spiritual theological terms signifies an affectivity of atonement and redemptive love. In this way, the movement towards dialogue reveals a synodal path and holy ground to walk together and imagine an integral ecology of difference and mystery to transform words into sacrifice and truth into redemptive love. Journeying together upon such holy ground witnesses to a spiritual theology of dialogue envisioning a place to hear the “good news” (Lk 4:16) and encounter “the hunger and thirst for righteousness” (Matt 5:6). Full article
(This article belongs to the Section Religions and Theologies)
12 pages, 4888 KiB  
Article
Compact Partially End-Pumped Innoslab Laser Based on Micro-Cylindrical Lens Array Homogenizer
by Xinhui Sun, Xiaonan Zhao, Jinxin Chen, Yajun Wu, Yibin Fu, Gang Cheng, Xi Chen, Pan Liu, Linhao Shang, Guangqiang Fan, Huihui Gao, Yan Xiang and Tianshu Zhang
Photonics 2024, 11(10), 932; https://doi.org/10.3390/photonics11100932 - 1 Oct 2024
Viewed by 1120
Abstract
We demonstrate a compact, partially end-pumping Innoslab laser based on a micro-cylindrical lens array homogenizer. A dimension of 12 × 0.4 mm2 flat-top pumping line with a Gaussian intensity distribution across the line was simulated by the ray tracing technique. The rate [...] Read more.
We demonstrate a compact, partially end-pumping Innoslab laser based on a micro-cylindrical lens array homogenizer. A dimension of 12 × 0.4 mm2 flat-top pumping line with a Gaussian intensity distribution across the line was simulated by the ray tracing technique. The rate equations considering the asymmetric transverse spatial distributions are theoretically developed. The simulation results are in good agreement with the experimental results. Preliminary data shows that for a pump power of 260 W, a maximum pulse energy of 15.7 mJ was obtained with a pulse width of 8.5 ns at a repetition frequency of 1 kHz. The beam quality M2 factors in the unstable and stable directions were 1.732 and 1.485, respectively. The technology has been successfully applied to temperature and humidity profiling lidar and ozone lidar and has been productized, yielding direct economic value. Full article
(This article belongs to the Section Lasers, Light Sources and Sensors)
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12 pages, 5026 KiB  
Article
Optical Characterization of a Rotationally Asymmetric Refractive Multifocal Intraocular Lens Compared to a Standard Monofocal One
by César Albarrán-Diego, María García-Montero, Nuria Garzón and José Antonio Gómez-Pedrero
Appl. Sci. 2024, 14(13), 5561; https://doi.org/10.3390/app14135561 - 26 Jun 2024
Viewed by 1870
Abstract
This study compares a standard monofocal intraocular lens (IOL) with two rotationally asymmetric refractive multifocal IOLs, analyzing power profiles and wavefront data across three nominal powers. Tested IOLs included monofocal Acunex AN6 and multifocal AN6V (addition +1.50 D) and AN6VM (addition +3.00 D) [...] Read more.
This study compares a standard monofocal intraocular lens (IOL) with two rotationally asymmetric refractive multifocal IOLs, analyzing power profiles and wavefront data across three nominal powers. Tested IOLs included monofocal Acunex AN6 and multifocal AN6V (addition +1.50 D) and AN6VM (addition +3.00 D) by Teleon Surgical, at powers +10.00 D, +20.00 D, and +30.00 D. Using NIMO TR1504, power profiles, spherical aberration, and coma were analyzed. Multifocal lenses displayed an asymmetrical design, with zones for far and near vision and a central notch for far power. The multifocal AN6V and AN6VM showed neutral spherical aberration in the center, increasing to positive values, and finally achieving negative values towards the periphery. The vertical coma coefficient [Z(3:−1)] remains almost stable for the monofocal IOLs. The lower-addition multifocal IOLs induce primary vertical coma of +0.11 microns at 3 mm away from the lens center compared to +0.21 microns obtained with the high-addition lens. We can conclude that the multifocal AN6V and AN6VM lenses display an asymmetrical design. The final addition provided by these lenses depends on its nominal power. The variation of SA with optic size is more pronounced for the monofocal model, and it is dependent on the nominal power. Full article
(This article belongs to the Special Issue Optical Imaging in Biomedical Engineering)
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21 pages, 4317 KiB  
Article
Enhanced Encrypted Traffic Analysis Leveraging Graph Neural Networks and Optimized Feature Dimensionality Reduction
by In-Su Jung, Yu-Rae Song, Lelisa Adeba Jilcha, Deuk-Hun Kim, Sun-Young Im, Shin-Woo Shim, Young-Hwan Kim and Jin Kwak
Symmetry 2024, 16(6), 733; https://doi.org/10.3390/sym16060733 - 12 Jun 2024
Cited by 3 | Viewed by 2456
Abstract
With the continuously growing requirement for encryption in network environments, web browsers are increasingly employing hypertext transfer protocol security. Despite the increase in encrypted malicious network traffic, the encryption itself limits the data accessible for analyzing such behavior. To mitigate this, several studies [...] Read more.
With the continuously growing requirement for encryption in network environments, web browsers are increasingly employing hypertext transfer protocol security. Despite the increase in encrypted malicious network traffic, the encryption itself limits the data accessible for analyzing such behavior. To mitigate this, several studies have examined encrypted network traffic by analyzing metadata and payload bytes. Recent studies have furthered this approach, utilizing graph neural networks to analyze the structural data patterns within malicious encrypted traffic. This study proposed an enhanced encrypted traffic analysis leveraging graph neural networks which can model the symmetric or asymmetric spatial relations between nodes in the traffic network and optimized feature dimensionality reduction. It classified malicious network traffic by leveraging key features, including the IP address, port, CipherSuite, MessageLen, and JA3 features within the transport-layer-security session data, and then analyzed the correlation between normal and malicious network traffic data. The proposed approach outperformed previous models in terms of efficiency, using fewer features while maintaining a high accuracy rate of 99.5%. This demonstrates its research value as it can classify malicious network traffic with a high accuracy based on fewer features. Full article
(This article belongs to the Section Computer)
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13 pages, 2843 KiB  
Article
Asymmetrical Three-Dimensional Conformal Imaging Lens
by Desen Gong, Yixiao Ge, Wen Xiao and Huanyang Chen
Photonics 2024, 11(6), 543; https://doi.org/10.3390/photonics11060543 - 7 Jun 2024
Viewed by 1513
Abstract
Absolute instrument refers to a media that can make light rays to propagate in a closed orbit and perform imaging and self-imaging. In the past few decades, traditional investigations into absolute instrument have been centered on the two-dimensional plane and rotational symmetry situations, [...] Read more.
Absolute instrument refers to a media that can make light rays to propagate in a closed orbit and perform imaging and self-imaging. In the past few decades, traditional investigations into absolute instrument have been centered on the two-dimensional plane and rotational symmetry situations, and have paid less attention to three-dimensional counterparts. In this article, we design two types of three-dimensional non-spherically symmetric absolute instruments based on conformal inverse transformation, which originated from the three-dimensional Luneburg lens and Lissajous lens. We carry out ray tracing on the optical performance of these new lenses and analyze the imaging laws. Our work enlarges the family of absolute instruments from two dimensions to three dimensions and symmetry to asymmetry, which may allow for imaging applications in optical waves. Full article
(This article belongs to the Special Issue Recent Advances in Optical Metamaterials and Metasurfaces)
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