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Record 73 of
Title:Influence of Scattered Sunlight for Wind Measurements with the O2(a1Δg) Dayglow
Author(s):He, Weiwei(1); Hu, Xiangrui(1); Wang, Houmao(2); Wang, Daoqi(1); Li, Juan(3); Li, Faquan(4); Wu, Kuijun(1)
Source: Remote Sensing Volume: 15 Issue: 1 Article Number: 232 DOI: 10.3390/rs15010232 Published: January 2023
Abstract:Observing the O2(a1Δg) dayglow with the limb-viewing DASH instrument enables remote sensing of neutral wind in near space. Many advantages are gained by using this new approach, but the influence factors on measurement accuracy have not been thoroughly investigated. This paper reports the quantitative evaluation of the wind error caused by scattered sunlight. The spectral concept of the O2(a1Δg) band and the measurement technique are briefly described. A comprehensive truth model simulation that is based on atmospheric limb radiance spectra and the instrument concept are used to obtain interferogram images. The algorithm, which uses these images to retrieve the interferogram containing information solely from the target altitude, is described. The self-absorption effect is taken into account in the unraveling of the line-of-sight integration. The influence of scattered sunlight on the limb-viewing weight and signal-to-noise ratio, two definitive factors for wind definitive factors, are also described. Representative wind precision profiles and their variation with surface albedo, aerosol loading, and cloud are presented. This indicates that the random error for Doppler wind is in the range of 2–3 m/s for the tangent height range from 45–80 km, and the wind precision under 45 km suffers significantly from scattered sunlight background. ? 2022 by the authors.
Accession Number: 20230213369984
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Record 74 of
Title:A dataset for fire and smoke object detection
Author(s):Wu, Siyuan(1,2); Zhang, Xinrong(3); Liu, Ruqi(2,4); Li, Binhai(5)
Source: Multimedia Tools and Applications Volume: 82 Issue: 5 Article Number: null DOI: 10.1007/s11042-022-13580-x Published: February 2023
Abstract:Fire and smoke object detection is of great significance due to the extreme destructive power of fire disasters. Most of the existing methods, whether traditional computer vision-based models with sensors or deep learning-based models have circumscribed application scenes with relatively poor detection speed and accuracy. This means seldom taking smoke into consideration and always focusing on classification tasks. To advance object detection research in fire and smoke detection, we introduce a dataset called DFS (Dataset for Fire and Smoke detection), which is of high quality, constructed by collecting from real scenes and annotated by strict and reasonable rules. To reduce the possibility of erroneous judgments caused by objects that are similar to fires in color and brightness, apart from annotating ‘fire’ and ‘smoke’, we annotate these objects as a new class ‘other’. There are a total of 9462 images named by the fire size, which can benefit different detection tasks. Furthermore, by carrying out extensive and abundant experiments on Various object detection models, we provide a comprehensive benchmark on our dataset. Experimental results show that DFS well represents real applications in fire and smoke detection and is quite challenging. We also test models with different training and testing proportions on our dataset to find the optimal split ratio in real situations. The dataset is released at https://github.com/siyuanwu/DFS-FIRE-SMOKE-Dataset. ? 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
Accession Number: 20223312570976
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Record 75 of
Title:Stratospheric Temperature Observations by Narrow Bands Ultra-High Spectral Resolution Sounder from Nadir-Viewing Satellites
Author(s):Wang, Sufeng(1,2); Feng, Yutao(1); Fu, Di(1); Kong, Liang(1); Li, Hongbo(1); Han, Bin(1); Lu, Feng(3)
Source: Remote Sensing Volume: 15 Issue: 8 Article Number: 1967 DOI: 10.3390/rs15081967 Published: April 2023
Abstract:Accurate stratospheric temperature observations are crucial for weather forecasts and climate change studies. This paper discusses a precise measurement method for the stratospheric temperature profile using narrow bands with ultra-high spectral resolution from nadir-viewing satellites. First, the CO2 absorption band around 15 μm is selected as the major sounding source by the calculation and analysis of the temperature Jacobian and the atmospheric molecular spectra. Next, the influence of spectral resolution, spectral range and instrumental noise on the sounding capability is analyzed, and the sounding feasibility of the single spectral band and multiple spectral bands is discussed under the condition that the spaceborne long-wave infrared space heterodyne spectrometer (SHS) is selected as suggested sounder onboard the satellite. Finally, the optimal joint-sounding scheme of narrow bands is proposed. The temperature retrieval and validation show that the joint-sounding of two discontinuous narrow bands can realize the high precision measurement of the stratospheric temperature profile for the given spectral resolution, spectral range, and instrumental noise. When the sounder adopts two narrow bands (the regions of 666.87–676.44 cm?1 and 683.58–693.15 cm?1) and a spectral resolution of 0.03 cm?1, the retrieval accuracy (RMSE) is about 0.9 K over a pressure range of 200 to 0.7 hPa (11.5–50 km). This study will provide technical preparation for high-precision and low-cost satellite sounder design for stratospheric temperature observations. ? 2023 by the authors.
Accession Number: 20231914056441
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Record 76 of
Title:Aggregation-Induced Emission (AIE), Life and Health
Author(s):Wang, Haoran(1,2); Li, Qiyao(1,34); Alam, Parvej(50,58); Bai, Haotian(3,58); Bhalla, Vandana(51,58); Bryce, Martin R.(55,58); Cao, Mingyue(4); Chen, Chao(2); Chen, Sijie(5,58); Chen, Xirui(6); Chen, Yuncong(7,58); Chen, Zhijun(8,58); Dang, Dongfeng(9,58); Ding, Dan(10,58); Ding, Siyang(11); Duo, Yanhong(12,58); Gao, Meng(13,58); He, Wei(2); He, Xuewen(14,58); Hong, Xuechuan(15,58); Hong, Yuning(11,58); Hu, Jing-Jing(29); Hu, Rong(16,58); Huang, Xiaolin(6,58); James, Tony D.(53,58); Jiang, Xingyu(17,58); Konishi, Gen-Ichi(52,58); Kwok, Ryan T. K.(2,58); Lam, Jacky W. Y.(2,58); Li, Chunbin(18); Li, Haidong(19); Li, Kai(20,58); Li, Nan(21); Li, Wei-Jian(22); Li, Ying(23,58); Liang, Xing-Jie(24,25,58); Liang, Yongye(26,58); Liu, Bin(27,58); Liu, Guozhen(28,58); Liu, Xingang(27); Lou, Xiaoding(29,58); Lou, Xin-Yue(30); Luo, Liang(31,58); McGonigal, Paul R.(58,58); Mao, Zong-Wan(32,58); Niu, Guangle(4,58); Owyong, Tze Cin(11); Pucci, Andrea(57,58); Qian, Jun(33,58); Qin, Anjun(34,58); Qiu, Zijie(1,58); Rogach, Andrey L.(54,58); Situ, Bo(35); Tanaka, Kazuo(56,58); Tang, Youhong(36,58); Wang, Bingnan(34); Wang, Dong(37,58); Wang, Jianguo(18,58); Wang, Wei(22); Wang, Wen-Xiong(38,58); Wang, Wen-Jin(32,39); Wang, Xinyuan(26); Wang, Yi-Feng(24,25); Wu, Shuizhu(40,58); Wu, Yifan(23); Xiong, Yonghua(6); Xu, Ruohan(9); Yan, Chenxu(41); Yan, Saisai(37); Yang, Hai-Bo(22,58); Yang, Lin-Lin(1); Yang, Mingwang(2); Yang, Ying-Wei(30,58); Yoon, Juyoung(42,58); Zang, Shuang-Quan(20,58); Zhang, Jiangjiang(17,43); Zhang, Pengfei(44,58); Zhang, Tianfu(25); Zhang, Xin(45,46,58); Zhang, Xin(28); Zhao, Na(21,58); Zhao, Zheng(1,58); Zheng, Jie(47,58); Zheng, Lei(35,58); Zheng, Zheng(48,58); Zhu, Ming-Qiang(49,58); Zhu, Wei-Hong(41,58); Zou, Hang(35); Tang, Ben Zhong(1,2,58)
Source: ACS Nano Volume: 17 Issue: 15 Article Number: null DOI: 10.1021/acsnano.3c03925 Published: August 8, 2023
Abstract:Light has profoundly impacted modern medicine and healthcare, with numerous luminescent agents and imaging techniques currently being used to assess health and treat diseases. As an emerging concept in luminescence, aggregation-induced emission (AIE) has shown great potential in biological applications due to its advantages in terms of brightness, biocompatibility, photostability, and positive correlation with concentration. This review provides a comprehensive summary of AIE luminogens applied in imaging of biological structure and dynamic physiological processes, disease diagnosis and treatment, and detection and monitoring of specific analytes, followed by representative works. Discussions on critical issues and perspectives on future directions are also included. This review aims to stimulate the interest of researchers from different fields, including chemistry, biology, materials science, medicine, etc., thus promoting the development of AIE in the fields of life and health. ? 2023 American Chemical Society. All rights reserved.
Accession Number: 20233814758415
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Record 77 of
Title:Hierarchical domain structures associated with oxygen octahedra tilting patterns in lead-free (Bi1/2Na1/2)TiO3
Author(s):Hu, Dongli(1,2); Fan, Zhongming(3); Sawyer, William(4); Henderson, Mitchell(4); Luo, Duan(1,5); Liu, Xiaoming(3); Gu, Hui(2); Tan, Xiaoli(3); Wen, Jianguo(1)
Source: Nanotechnology Volume: 34 Issue: 7 Article Number: 075702 DOI: 10.1088/1361-6528/aca030 Published: February 12, 2023
Abstract:Hierarchical domain structures associated with oxygen octahedra tilting patterns were observed in lead-free (Bi1/2Na1/2)TiO3 ceramics using aberration-corrected high-resolution transmission electron microscopy (HRTEM). Three types of domains are induced by distinct mechanisms: the ‘orientation-domain’ is induced at micrometer scale formed by different tilting orientations of the oxygen octahedra, the ‘meso-chemical-domain’ occurs at a few tens of nanometer scale by chemical composition variation on the A-site in the ABO3 perovskite structure, and the ‘nano-cluster-region’ runs across several unit-cells with apparent A-site cation segregation with oxygen vacancies clustering around Na cations. Based on HRTEM amplitude contrast imaging (ACI), the correlation between the oxygen octahedral tilting pattern and compositional non-stoichiometry was established. The role of the hierarchical domain structure associated with the tilting patterns of the oxygen octahedra on the ferroelectric behavior of (Bi1/2Na1/2)TiO3 is also discussed. ? 2022 IOP Publishing Ltd.
Accession Number: 20225013232190
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Record 78 of
Title:Style transformed synthetic images for real world gaze estimation by using residual neural network with embedded personal identities
Author(s):Wang, Quan(1,2); Wang, Hui(1,2,3); Dang, Ruo-Chen(1,2); Zhu, Guang-Pu(1,2,3); Pi, Hai-Feng(1,2); Shic, Frederick(4); Hu, Bing-liang(1,2)
Source: Applied Intelligence Volume: 53 Issue: 2 Article Number: null DOI: 10.1007/s10489-022-03481-9 Published: January 2023
Abstract:Gaze interaction is essential for social communication in many scenarios; therefore, interpreting people’s gaze direction is helpful for natural human-robot interactions and human-virtual characters. In this study, we first adopt a residual neural network (ResNet) structure with an embedding layer of personal identity (ID-ResNet) that outperformed the current best result of 2.51° with MPIIGaze data, a benchmark dataset for gaze estimation. To avoid using manually labelled data, we used UnityEye synthetic images with and without style transformation as the training data. We exceeded the previously reported best result with MPIIGaze data (from 2.76° to 2.55°) and UT-Multiview data (from 4.01° to 3.40°). In addition, it only needs to fine-tune with a few "calibration" examples for a new person to yield significant performance gains. In addition, we presented the KLBS-eye dataset that contains 15,350 images collected from 12 participants while looking in nine known directions and received the state-of-the-art result of (0.59 ± 1.69°). ? 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
Accession Number: 20221912072202
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Record 79 of
Title:A Plant Disease Classification Algorithm Based on Attention MobileNet V2
Author(s):Wang, Huan(1); Qiu, Shi(1); Ye, Huping(2,3); Liao, Xiaohan(2,3,4)
Source: Algorithms Volume: 16 Issue: 9 Article Number: 442 DOI: 10.3390/a16090442 Published: September 2023
Abstract:Plant growth is inevitably affected by diseases, and one effective method of disease detection is through the observation of leaf changes. To solve the problem of disease detection in complex backgrounds, where the distinction between plant diseases is hindered by large intra-class differences and small inter-class differences, a complete plant-disease recognition process is proposed. The process was tested through experiments and research into traditional and deep features. In the face of difficulties related to plant-disease classification in complex backgrounds, the advantages of strong interpretability of traditional features and great robustness of deep features are fully utilized, and include the following components: (1) The OSTU algorithm based on the naive Bayes model is proposed to focus on where leaves are located and remove interference from complex backgrounds. (2) A multi-dimensional feature model is introduced in an interpretable manner from the perspective of traditional features to obtain leaf characteristics. (3) A MobileNet V2 network with a dual attention mechanism is proposed to establish a model that operates in both spatial and channel dimensions at the network level to facilitate plant-disease recognition. In the Plant Village open database test, the results demonstrated an average SEN of 94%, greater than other algorithms by 12.6%. ? 2023 by the authors.
Accession Number: 20233914807115
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Record 80 of
Title:Metallic Plasmonic Nanostructure Arrays for Enhanced Solar Photocatalysis
Author(s):Jia, Huaping(1,2,3); Tsoi, Chi Chung(2,3); Abed, Abdel El(4); Yu, Weixing(5); Jian, Aoqun(1); Sang, Shengbo(1); Zhang, Xuming(2,3)
Source: Laser and Photonics Reviews Volume: 17 Issue: 5 Article Number: 2200700 DOI: 10.1002/lpor.202200700 Published: May 2023
Abstract:Plasmon-enhanced photocatalysis has emerged as a promising technology for solar-to-chemical energy conversion. Compared to isolated or disordered metal nanostructures, by controlling the morphology, composition, size, spacing, and dispersion of individual nanocomponents, plasmonic nanostructure arrays with coupling architectures yield strong broadband light-harvesting capability, efficient charge transfer, enhanced local electromagnetic fields, and large contact interfaces. Although metallic nanostructure arrays are extensively studied for various applications, such as refractive index sensing, surface-enhanced spectroscopy, plasmon-enhanced luminescence, plasmon nanolasing, and perfect light absorption, the connection between surface plasmon resonance and enhanced photocatalysis remains relatively unexplored. In this study, an overview of plasmonic nanostructure arrays over a broad range, from 0D to 3D, for efficient photocatalysis is presented. By reviewing the fundamental mechanisms, recent applications, and latest developments of plasmonic nanostructure arrays in solar-driven chemical conversion, this study reports on the latest guidance toward the integration of plasmonic nanostructures for functional devices in the fields of plasmonic, photonics, photodetection, and solar-energy harvesting. ? 2022 Wiley-VCH GmbH.
Accession Number: 20230613561522
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Record 81 of
Title:LED array microscopy system correction method with comprehensive error parameters optimized by phase smoothing criterion
Author(s):Yang, Zewen(1); Zhang, Lu(1); Liu, Tong(1); Wu, Haoyu(1); Tang, Zhiyuan(2); Fan, Chen(1); Liu, Xiaolong(3); Zhang, Zhenxi(4); Zhao, Hong(1)
Source: Biomedical Optics Express Volume: 14 Issue: 9 Article Number: null DOI: 10.1364/BOE.497681 Published: 2023
Abstract:LED array microscopy is a novel computational imaging technique that can achieve two-dimensional (2D) phase imaging and three-dimensional (3D) refractive index imaging with both high resolution and a large field of view. Although its experimental setup is simple, the errors caused by LED array position and light source central wavelength obviously decrease the quality of reconstructed results. To solve this problem, comprehensive error parameters optimized by the phase smoothing criterion are put forward in this paper. The central wavelength error and 3D misalignment model with six freedom degree errors of LED array are considered as the comprehensive error parameters when the spatial positional and optical features of arbitrarily placed LED array are unknown. Phase smoothing criterion is also introduced to the cost function for optimizing comprehensive error parameters to improve the convergence results. Compared with current system correction methods, the simulation and experimental results show that the proposed method in this paper has the best reconstruction accuracy, which can be well applied to an LED array microscope system with unknown positional and optical features of the LED array. ? 2023 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement.
Accession Number: 20233914773799
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Record 82 of
Title:Ultrahigh bandwidth applications of optical microcombs
Author(s):Tan, M.(1); Sun, Y.(2); Wu, J.(1); Xu, X.(3); Li, Yang(1); Corcoran, B.(4); Chu, S.(5); Little, B.(6); Morandotti, R.(7); Mitchell, A.(1); Moss, D.J.(2)
Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 12438 Issue: null Article Number: 1243804 DOI: 10.1117/12.2647952 Published: 2023
Abstract:We report ultrahigh bandwidth applications of Kerr microcombs at data rates beyond 10 Terabits/s. Optical neural networks can dramatically accelerate the computing speed to overcome the inherent bandwidth bottleneck of electronics. At the same time, digital signal processing has become central to many fields, from coherent optical telecommunications where it is used to compensate signal impairments, to image processing, important for observational astronomy, medical diagnosis, autonomous driving, big data and particularly artificial intelligence. Digital signal processing had traditionally been performed electronically, but new applications, particularly those involving real time video image processing, are creating unprecedented demand for ultrahigh performance, including bandwidth and reduced energy consumption. We use a new and powerful class of micro-comb called soliton crystals that exhibit robust operation and stable generation as well as a high intrinsic efficiency with a low spacing of 48.9 GHz. We demonstrate a universal optical vector convolutional accelerator operating at 11 Tera-OPS/s (TOPS) on 250,000 pixel images for 10 kernels simultaneously - enough for facial image recognition. We use the same hardware to sequentially form a deep optical CNN with ten output neurons, achieving successful recognition of full 10 digits with 900 pixel handwritten digit images. Finally, we demonstrate a photonic digital signal processor operating at 18 Tb/s and use it to process multiple simultaneous video signals in real-time. The system processes 400,000 video signals concurrently, performing 34 functions simultaneously that are key to object edge detection, edge enhancement and motion blur. As compared with spatial-light devices used for image processing, our system is not only ultra-high speed but highly reconfigurable and programable, able to perform many different functions without any change to the physical hardware. Our approach, based on an integrated Kerr soliton crystal microcomb, opens up new avenues for ultrafast robotic vision and machine learning. ? 2023 SPIE.
Accession Number: 20232114138505
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Record 83 of
Title:The nanoscale imaging of the bulk polycrystalline material with the effects of depth of field and field of view based on x-ray free electron laser
Author(s):Wang, Chuan(1,2,3); Liang, Yihan(4); Hu, Ronghao(1,2,3); He, Kai(5); Gao, Guilong(5); Yan, Xin(5); Yao, Dong(5); Wang, Tao(5); Li, Xiaoya(4); Tian, Jinshou(5); Zhu, Wenjun(4); Lv, Meng(1,2,3)
Source: arXiv Volume: null Issue: null Article Number: null DOI: null Published: June 15, 2023
Abstract:We study the effects of the depth of field (DoF) and field of view (FoV) of the optical lens and extract the scattered light of the region to be imaged within the bulk polycrystalline material based on the objective BCDI. We describe how the DoF and FoV quantitatively limit the diffraction volume, where the DoF and FoV limit the scattering region parallel and perpendicular to the direction of the light source respectively. We demonstrate this scheme by simulating the separate imaging of a submicron-sized crack region within a few μm-sized Si bulk material, and obtain a high imaging quality. This scheme enables imaging of selected regions within bulk polycrystalline materials with the resolution up to the order of 10 nm. Copyright ? 2023, The Authors. All rights reserved.
Accession Number: 20230217056
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Record 84 of
Title:Range-Blind Underwater Single-Photon Imaging with Polarization
Author(s):Wang, Jie(1,2,3,4); Hao, Wei(1,2,4); Chen, Songmao(1,2,4); Zhang, Zhenyang(1,2,3,4); Xu, Weihao(1,3,4); Xie, Meilin(1,2,4); Zhu, Wenhua(5); Su, Xiuqin(1,2,4)
Source: SSRN Volume: null Issue: null Article Number: null DOI: 10.2139/ssrn.4463822 Published: May 30, 2023
Abstract:To address the count loss of close-range underwater targets caused by Device Export Photons(DEP), a polarization-based underwater mono-static single-photon imaging method is proposed in this paper. The proposed method exploits the polarization characteristic of light to effectively alleviate DEP, which improves the target detection efficiency by significantly diminishing the detection probability of DEP. Experiments conducted on underwater close-range targets demonstrate that our method is able to reduce DEP by an average of 98.2%. The target profile can then be visible from the return photons while the unpolarization system can not reconstruct target, and the ranging precision of the polarization system reaches a millimeter-level.Finally, the target profile is reconstructed using non-local pixel correlations algorithm. ? 2023, The Authors. All rights reserved.
Accession Number: 20230173855
