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CAEFusion: A New Convolutional Autoencoder-Based Infrared and Visible Light Image Fusion Algorithm 被引量:1
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作者 Chun-Ming Wu Mei-Ling Ren +1 位作者 Jin Lei Zi-Mu Jiang 《Computers, Materials & Continua》 SCIE EI 2024年第8期2857-2872,共16页
To address the issues of incomplete information,blurred details,loss of details,and insufficient contrast in infrared and visible image fusion,an image fusion algorithm based on a convolutional autoencoder is proposed... To address the issues of incomplete information,blurred details,loss of details,and insufficient contrast in infrared and visible image fusion,an image fusion algorithm based on a convolutional autoencoder is proposed.The region attention module is meant to extract the background feature map based on the distinct properties of the background feature map and the detail feature map.A multi-scale convolution attention module is suggested to enhance the communication of feature information.At the same time,the feature transformation module is introduced to learn more robust feature representations,aiming to preserve the integrity of image information.This study uses three available datasets from TNO,FLIR,and NIR to perform thorough quantitative and qualitative trials with five additional algorithms.The methods are assessed based on four indicators:information entropy(EN),standard deviation(SD),spatial frequency(SF),and average gradient(AG).Object detection experiments were done on the M3FD dataset to further verify the algorithm’s performance in comparison with five other algorithms.The algorithm’s accuracy was evaluated using the mean average precision at a threshold of 0.5(mAP@0.5)index.Comprehensive experimental findings show that CAEFusion performs well in subjective visual and objective evaluation criteria and has promising potential in downstream object detection tasks. 展开更多
关键词 Image fusion deep learning auto-encoder(AE) infrared visible light
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Photoprotective Ability of Sunscreens against Ultraviolet, Visible Light and Near-Infrared Radiation
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作者 Yohei Tanaka 《Optics and Photonics Journal》 2023年第6期140-146,共7页
Despite the widespread prevalence of daily sunscreen usage, solar-induced skin damage continues to occur. We have previously reported that solar visible light and near-infrared, in addition to ultraviolet radiation, p... Despite the widespread prevalence of daily sunscreen usage, solar-induced skin damage continues to occur. We have previously reported that solar visible light and near-infrared, in addition to ultraviolet radiation, perform as aging factors and induce deleterious effects such as photoaging, vasodilation, muscle thinning, skin ptosis, photoimmunosupression and photocarcinogenesis. Despite this, most commonly used sunscreens only block ultraviolet radiation. To evaluate the complete solar-spectrum blocking ability of sunscreens produced by internationally well-known companies, a double-beam spectrophotometer was used to optically measure the transmission spectra. The spectrophotometer utilizes a unique, single monochromatic design covering a wavelength range of 240 to 2600 nm. Sunscreens (thickness, 0.1 mm, SPF50+, PA+++ or ++++) from internationally well-known companies blocked 78.8% - 99.9% of ultraviolet, 33.4% - 99.6% of visible light, and 27.0% - 76.4% of near-infrared. It can be concluded that while most commercially available sunscreens filter ultraviolet radiation, they are not effective at blocking visible light and near-infrared radiation. The results of this study imply that sunscreens that provide comprehensive photoprotection from ultraviolet through to near-infrared should be considered to prevent skin photodamage. 展开更多
关键词 Anti-Photoageing PHOTOPROTECTION SUNSCREEN ULTRAVIOLET Visible light NEAR-infrared
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Novel Low Viscosity Zinc Oxide, Iron Oxides and Erioglaucine Sunscreen Potential to Protect from Ultraviolet, Visible Light and Near-Infrared Radiation
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作者 Yohei Tanaka Richard Parker +1 位作者 Amaryllis Aganahi Ailen Pedroso 《Optics and Photonics Journal》 2023年第9期217-226,共10页
Despite the widespread recommendation and use of sunscreens and ultraviolet blocking materials, solar-induced skin damage and photoageing continues to pose a problem to human health worldwide. We have previously repor... Despite the widespread recommendation and use of sunscreens and ultraviolet blocking materials, solar-induced skin damage and photoageing continues to pose a problem to human health worldwide. We have previously reported that solar visible light and near-infrared also contribute to skin damage and photo ageing. Most commonly recommended sunscreens are only effective throughout the UV spectrum, offering no protection from visible light and near-infrared. A possible solution could be to augment sunscreens with metal oxides which block visible light and near-infrared radiation. To evaluate the enhanced solar-spectrum blocking ability of novel low viscosity sunscreen containing zinc and iron oxides, a double-beam spectrophotometer was used to optically measure the transmission spectra. The spectrophotometer deploys a unique, single monochromatic design to detect wavelength penetration in the range of 240 to 2600 nm. The Sunscreen base without zinc oxide and iron oxides (control) blocked over 80% of ultraviolet-C and ultraviolet-B but did not block ultraviolet-A, visible light, or near-infrared. The novel low viscosity zinc oxide sample blocked almost over 90% ultraviolet, but did not block visible light and near-infrared sufficiently. However, the samples with the novel low viscosity zinc oxide, iron oxides and erioglaucine blocked almost over 90% of ultraviolet, visible light and near-infrared. It can be concluded that this novel combination of low viscosity zinc oxide, iron oxides and erioglaucine is effective at blocking ultraviolet, visible light and near-infrared radiation. The results of this study imply that sunscreens that provide comprehensive photoprotection from ultraviolet through to near-infrared should be adopted to prevent skin photodamage. 展开更多
关键词 Anti-Photoageing Photoimmunosuppression PHOTOPROTECTION SUNSCREEN ULTRAVIOLET Visible light NEAR-infrared
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Photoprotective Ability of Colored Iron Oxides in Tinted Sunscreens against Ultraviolet, Visible Light and Near-Infrared Radiation
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作者 Yohei Tanaka Richard Parker Amaryllis Aganahi 《Optics and Photonics Journal》 2023年第8期199-208,共10页
Solar-induced skin damage continues to pose a problem to human health worldwide, despite the widespread recommendation and use of sunscreens. We have previously reported that solar visible light and near-infrared also... Solar-induced skin damage continues to pose a problem to human health worldwide, despite the widespread recommendation and use of sunscreens. We have previously reported that solar visible light and near-infrared also contribute to skin damage and photoageing. Most commonly recommended sunscreens are only effective throughout the UV spectrum, offering no protection from visible light and near-infrared. To evaluate the enhanced solar-spectrum blocking ability of iron oxides, a double-beam spectrophotometer was used to optically measure the transmission spectra. The spectrophotometer deploys a unique, single monochromatic design to detect wavelength penetration in the range of 240 to 2600 nm. The sample without iron oxide (control) blocked over 80% of ultraviolet-C and ultraviolet-B but did not block ultraviolet-A, visible light, or near-infrared wavelengths. The samples with yellow, and red iron oxide blocked over 90% ultraviolet, but did not block visible light and near-infrared effectively. The sample with black iron oxide blocked visible light, and near-infrared effectively compared with other samples with yellow, blue, and red iron oxide. The sample with red and black iron oxides, and the sample with yellow, blue, red, and black iron oxides blocked ultraviolet through to near-infrared. It can be concluded that dark colored iron oxide combinations are effective at blocking from ultraviolet through to visible light and near-infrared radiation. The results of this study may also suggest that biological colour of human skin and subcutaneous tissues are conserved for comprehensive photoprotection. 展开更多
关键词 Anti-Photoageing Photoimmunosuppression PHOTOPROTECTION SUNSCREEN ULTRAVIOLET Visible light NEAR-infrared
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Near-infrared lead chalcogenide quantum dots:Synthesis and applications in light emitting diodes 被引量:2
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作者 Haochen Liu Huaying Zhong +6 位作者 Fankai Zheng Yue Xie Depeng Li Dan Wu Ziming Zhou Xiao-Wei Sun Kai Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第12期1-13,共13页
This paper reviews the recent progress in the synthesis of near-infrared(NIR) lead chalcogenide(PbX;PbX = PbS,PbSe, PbTe) quantum dots(QDs) and their applications in NIR QDs based light emitting diodes(NIR-QLEDs). It ... This paper reviews the recent progress in the synthesis of near-infrared(NIR) lead chalcogenide(PbX;PbX = PbS,PbSe, PbTe) quantum dots(QDs) and their applications in NIR QDs based light emitting diodes(NIR-QLEDs). It summarizes the strategies of how to synthesize high efficiency PbX QDs and how to realize high performance Pb X based NIR-QLEDs. 展开更多
关键词 lead chalcogenide quantum dots NEAR-infrared light emitting diodes
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Influence of Transparent Anode on Luminescent Performance of Near-infrared Organic Light-emitting Diodes 被引量:2
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作者 GUAN He-song CHENG Chuan-hui +6 位作者 LI Wan-cheng GENG Dong-feng FAN Zhao-qi CHANG Yu-chun ZHAO Wang GUO Zhen-qiang DU Guo-tong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第6期786-790,共5页
The optical transmission(200--2000 nm), sheet resistance and work functions of indium-tin oxide(ITO)(100 Ω/), ITO(12 Ω/), zinc-oxide(ZnO), aluminum-doped ZnO(AZO) and polyaniline(PANI) films were inves... The optical transmission(200--2000 nm), sheet resistance and work functions of indium-tin oxide(ITO)(100 Ω/), ITO(12 Ω/), zinc-oxide(ZnO), aluminum-doped ZnO(AZO) and polyaniline(PANI) films were investigated. Near-infrared organic light-emitting diodes(NIR-OLEDs) emitting around 1.54 μm based on Er(DBM)3Phen with ITO(100 Ω/), ITO(12 Ω/) and PANI as anodes, respectively, were fabricated. The device structure was anode/4"-tris(N-3-methylphenyl-N-phenyl-amino)-triphenylamine(m-MTDATA)/ N,N'-di-l-naphthyl- N,N'-diphenylbenzidine(NPB)/Er(DBM)3Phen/tris-(8-hydroxyquinoline) aluminum(Alq3)/A1. The results suggest that the performance of NIR-OLEDs with ITO(100 Ω/), which has a lower Sn content, as anodes appear to be better than that of NIR-OLEDs with ITO(12 Ω/) and PANI as anodes, respectively. The high N1R transmittance of ITO(100 Ω/) is a major reason for the relatively high NIR EL efficiency. The more balanced holes and electrons in the device based on ITO(100 Ω/) are another reasons. 展开更多
关键词 Transparent electrode Near-infrared(NIR) Organic light-emitting diode(OLED)
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Infrared light-emitting diodes based on colloidal Pb Se/Pb S core/shell nanocrystals
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作者 Byung-Ryool Hyun Mikita Marus +7 位作者 Huaying Zhong Depeng Li Haochen Liu Yue Xie Weon-kyu Koh Bing Xu Yanjun Liu Xiao Wei Sun 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第1期482-488,共7页
Colloidal Pb Se nanocrystals(NCs)have gained considerable attention due to their efficient carrier multiplication and emissions across near-infrared and short-wavelength infrared spectral ranges.However,the fast degra... Colloidal Pb Se nanocrystals(NCs)have gained considerable attention due to their efficient carrier multiplication and emissions across near-infrared and short-wavelength infrared spectral ranges.However,the fast degradation of colloidal Pb Se NCs in ambient conditions hampers their widespread applications in infrared optoelectronics.It is well-known that the inorganic thick-shell over core improves the stability of NCs.Here,we present the synthesis of Pb Se/Pb S core/shell NCs showing wide spectral tunability,in which the molar ratio of lead(Pb)and sulfur(S)precursors,and the concentration of sulfur and Pb Se NCs in solvent have a significant effect on the efficient Pb S shell growth.The infrared light-emitting diodes(IR-LEDs)fabricated with the Pb Se/Pb S core/shell NCs exhibit an external quantum efficiency(EQE)of 1.3%at 1280 nm.The ligand exchange to optimize the distance between NCs and chloride treatment are important processes for achieving high performance on Pb Se/Pb S NC-LEDs.Our results provide evidence for the promising potential of Pb Se/Pb S NCs over the wide range of infrared optoelectronic applications. 展开更多
关键词 Pb Se/Pb S core/shell nanocrystal ligand exchange infrared light-emitting diodes external quantum efficiency
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Light-Induced Mid-Infrared Emission of Liquid Carbon Tetrachloride and Benzene
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作者 Sofya Terpugova Olga Degtyareva +1 位作者 Valery Savransky Evgeni Terpugov 《American Journal of Analytical Chemistry》 2015年第9期731-745,共15页
Light-induced infrared emission spectroscopy (LIRES) is a novel technique that permits to receive high-quality spectra in the mid-infrared region. Low-intensity visible light connected to a highly sensitive FTIR spect... Light-induced infrared emission spectroscopy (LIRES) is a novel technique that permits to receive high-quality spectra in the mid-infrared region. Low-intensity visible light connected to a highly sensitive FTIR spectrometer is more advantageous for studying any samples, including biological samples without any damage. This technique permits obtaining unique information on the molecule structure via vibrational excitation fundamental frequencies, overtones, and combination modes. It also enables a direct observation of vibrational radiation transitions in vibrationally excited molecules as well as the channels of vibration energy redistribution, which is not allowed with any other method. In this work, the LIRES is being tested as a technique for studying of vibrationally-excited molecules of carbon tetrachloride and benzene in the liquid phase. On the other hand, using transparent liquids, we had tried to understand some of the physical phenomena that can drive emission in mid-IR. The characteristics of the infrared emission of both liquid species produced by different wavelength radiation from various types of light systems (100 - watt Xe-lamp and Nd:YAG laser;lambda = 1064 nm (8 mW) and lambda = 532 nm (4 mW)) are presented. We demonstrated that the IR-signal, as well as spectral properties of carbon tetrachloride and benzene, was dependent on the wavelength and power of excitation beam. Results obtained with different light sources show that the visible light produces a nonlinear IR-emission signal in transparent liquids. We believe that the visible light is the source of the nonlinear response and is producing the vibration excitation as well as photostimulated transformations of the molecules possessing the high activity for the nonlinear response. 展开更多
关键词 FT-IR EMISSION Spectroscopy light-INDUCED MID-infrared EMISSION Carbon TETRACHLORIDE BENZENE Xe-Lamp Nd:YAG Laser
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Biological Defenses against Ultra-Violet, Visible Light, and Near-Infrared Exposure
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作者 Yohei Tanaka Hideki Motomura Masafumi Jinno 《Optics and Photonics Journal》 2016年第1期8-14,共7页
Objective: Humans are increasingly exposed to artificial light and electromagnetic wave radiation, in addition to solar radiation. Many studies have shown the biological effects of ultra-violet and near-infrared expos... Objective: Humans are increasingly exposed to artificial light and electromagnetic wave radiation, in addition to solar radiation. Many studies have shown the biological effects of ultra-violet and near-infrared exposure, but few have extensively investigated the innate biological defenses within human tissues against visible light and near-infrared exposure. Herein, we investigated spectral properties of endogenous human biological defenses against ultra-violet to near-infrared. Methods: A double-beam spectrophotometer (190 - 2700 nm) was used to measure the transmission spectra of a saline solution used to imitate perspiration, and oil to imitate sebum, as well as human skin, blood, adipose tissue, and muscle. Results: Saline (thickness, 0.5 mm) blocked 27.5% - 98.6% of ultra-violet, 13.2% - 34.3% of visible light, and 10.7% - 99.8% of near-infrared. Oil (thickness, 0.5 mm) blocked 50.5% - 100% of ultra-violet, 28.7% - 54.8% of visible light, and 19.0% - 98.3% of near-infrared. Blood thicknesses of 0.05 and 0.5 mm blocked over 97.8%, 100% of ultra-violet, over 94.6%, 99.7% of visible light, and over 75.8%, 99.4% of near-infrared, respectively. Skin thicknesses of 0.25 and 0.5 mm blocked over 99.4%, 100% of ultra-violet and over 94.3%, 99.7% of visible light, and over 74.7%, 93.5% of near-infrared, respectively. Adipose tissue thickness of 0.25 and0.5 mm blocked over 98.3%, 100% of ultra-violet, over 94.7%, 99.7% of visible light, and over 88.1%, 98.6% of near-infrared, respectively. Muscle thickness of 0.25 and0.5 mm blocked over 95.4%, 99.8% of ultra-violet, over 93.1%, 99.5% of visible light, and over 86.9%, 98.3% of near-infrared, respectively. Conclusions: Humans possess endogenous biological protection against ultra-violet, visible light and near-infrared exposure on multiple levels, including through perspiration, sebum, blood, skin, adipose tissue, and muscle. Since solar and artificial radiation affects human tissues, biological defenses made of biological materials may be induced to protect subcutaneous tissues against these wavelengths. 展开更多
关键词 Biological Defenses NEAR-infrared Ultra-Violet Visible light
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Fabrication of Ag@Cu2O core-shell metal-semiconductor nanoparticles and high efficiency photocatalysis under visible- near-infrared light irradiation
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作者 Lele Wang Ailing Yang +1 位作者 Xichang Bao Renqiang Yang 《纳米科技》 2015年第5期43-50,共8页
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The Application of the Edge Sharpening Operator to the Breast Near-Infrared Imaging 被引量:1
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作者 Xiang Yan 1 , Li Kai yang 1 , Yang Xuan dong 1 , Wang Xiao fang 2 ,Zhang Xian lin 2 ,Zhu Yi jun 3 1. School of Physics and Technology, Wuhan University, Wuhan 430072, Hubei, China 2. Tumor Research Institute of Hubei Province, Wuhan 430079,Hubei, China 3. E Sea Digital Engineering Limited Company, Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2002年第4期421-425,共5页
The principles of Gradient operator, Laplacian operator, LOG operator and Sobel operator are discussed. Certain features of breast can be extracted in different degrees and aspects from original images by applying fou... The principles of Gradient operator, Laplacian operator, LOG operator and Sobel operator are discussed. Certain features of breast can be extracted in different degrees and aspects from original images by applying four edge sharpening operators to the breast near-infrared imaging. A great number of cases prove that compared with the other three operators, the improved Sobel operator can effectively extract the structural features of the breast from an original image. It can be concluded that the improved Sobel operator can assist in diagnosing breast diseases. 展开更多
关键词 edge sharpening OPERATOR NEAR infrared light breast diagnoses
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Intelligent Fusion of Infrared and Visible Image Data Based on Convolutional Sparse Representation and Improved Pulse-Coupled Neural Network 被引量:3
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作者 Jingming Xia Yi Lu +1 位作者 Ling Tan Ping Jiang 《Computers, Materials & Continua》 SCIE EI 2021年第4期613-624,共12页
Multi-source information can be obtained through the fusion of infrared images and visible light images,which have the characteristics of complementary information.However,the existing acquisition methods of fusion im... Multi-source information can be obtained through the fusion of infrared images and visible light images,which have the characteristics of complementary information.However,the existing acquisition methods of fusion images have disadvantages such as blurred edges,low contrast,and loss of details.Based on convolution sparse representation and improved pulse-coupled neural network this paper proposes an image fusion algorithm that decompose the source images into high-frequency and low-frequency subbands by non-subsampled Shearlet Transform(NSST).Furthermore,the low-frequency subbands were fused by convolutional sparse representation(CSR),and the high-frequency subbands were fused by an improved pulse coupled neural network(IPCNN)algorithm,which can effectively solve the problem of difficulty in setting parameters of the traditional PCNN algorithm,improving the performance of sparse representation with details injection.The result reveals that the proposed method in this paper has more advantages than the existing mainstream fusion algorithms in terms of visual effects and objective indicators. 展开更多
关键词 Image fusion infrared image visible light image non-downsampling shear wave transform improved PCNN convolutional sparse representation
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Optical Design and Stray Light Analysis of the Space Infrared Optical System 被引量:1
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作者 Yuchen Zhao Yanjun Xu +2 位作者 Changzheng Chen Fan Zhang Jianyue Ren 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第1期32-36,共5页
This article describes a novel configuration design for a re-imaging off-axis catadioptric space infrared optical system,and in order to satisfy the signal noise ratio requirements of the system,the stray light of the... This article describes a novel configuration design for a re-imaging off-axis catadioptric space infrared optical system,and in order to satisfy the signal noise ratio requirements of the system,the stray light of the system is necessary to analyze and restrain. The optical system with a focal length of 1 200 mm,an entrance pupil diameter of 600 mm,an F-number of 2,a field of view of 3°× 0. 15°,a working wave band of 8 μm-10 μm,and the image quality of the optical system almost approach to diffraction limits in all field of view.Then the mathematical models of stray light are built,and the suppressive structure is established to eliminate the effect of stray light. Finally,TraceP ro is used to analyze and simulate stray light with and without the suppressive structure,and also get the results of the PST curves. The results indicate that appropriate optical system and suppressive structure can highly reduce the stray light of the space infrared optical system. 展开更多
关键词 space infrared optical system off-axis optical system stray light Point Source Transmission(PST)
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基于CNN-Transformer双模态特征融合的目标检测算法 被引量:2
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作者 杨晨 侯志强 +2 位作者 李新月 马素刚 杨小宝 《光子学报》 EI CAS CSCD 北大核心 2024年第3期273-286,共14页
针对单模态目标检测的不足,提出了一种基于CNN-Transformer双模态特征融合的目标检测算法。在YOLOv5的基础上,构建了一个可以同时输入红外和可见光图像的双流特征提取网络;然后,分别提出了基于卷积神经网络结构的红外特征提取主干网络... 针对单模态目标检测的不足,提出了一种基于CNN-Transformer双模态特征融合的目标检测算法。在YOLOv5的基础上,构建了一个可以同时输入红外和可见光图像的双流特征提取网络;然后,分别提出了基于卷积神经网络结构的红外特征提取主干网络和基于Transformer结构的可见光特征提取主干网络,以提升对红外和可见光图像的特征提取能力;最后,按照中期融合的思想,设计了双模态特征融合模块,对两个分支对应尺度的双模态特征信息进行有效融合,实现跨模态信息互补。在数据集上对所提算法进行验证,实验结果表明,该算法在KAIST数据集上对双模态图像进行检测的结果,较基准算法单独检测红外图像和可见光图像,精度分别提升了5.7%和17.4%;在FLIR数据集上较基准算法,检测精度分别提升了11.6%和17.1%;在自建GIR数据集上,所提算法的检测精度也有明显提升。此外,该算法还可以单独处理红外或可见光图像,且检测精度较基准算法均有明显提升。 展开更多
关键词 目标检测 卷积神经网络 TRANSFORMER 双模态 特征融合 红外 可见光
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Electronic structure and infrared spectrum of a W_n C^(0,±) (n = 1-6) cluster 被引量:1
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作者 张秀荣 康张李 郭文录 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期204-211,共8页
WnC0'± (n= 1-6) clusters are investigated by using the density functional theory (DFT) at the B3LYP/LANL2DZ level. We find that the neutral, anionic and cationic ground state structures are similar within th... WnC0'± (n= 1-6) clusters are investigated by using the density functional theory (DFT) at the B3LYP/LANL2DZ level. We find that the neutral, anionic and cationic ground state structures are similar within the same size, and constituted by substituting a C atom for one W atom in the structures of Wn+1 clusters. The natural bond orbital (NBO) charge analyses indicate that the direction of electron transfer is from the W atom to the 2p orbital of the C atom. In addition, the calculated infrared spectra of the WnC0'± (n= 2-6) clusters manifest that the vibrational frequencies of neutral, anionic and cationic clusters are similar in a range of 80 cm-1-864 cm-1. The high frequency, strong peak modes are found to be an almost stretched deformation of the carbide atom. Finally, the polarizabilities of WnC0'± (n= 1-6) clusters are also discussed. 展开更多
关键词 WnC0'± (n= 1-6) clusters electronic structure infrared spectrum density functionaltheory
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Near-infrared observations of the Be/X-ray binary pulsar A0535+262
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作者 Sachindra Naik Blesson Mathew +2 位作者 D.P.K.Banerjee N.M.Ashok Rajeev R.Jaiswal 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第2期177-186,共10页
We present the results obtained from extensive near-infrared (IR) spectro- scopic and photometric observations of the Be/X-ray binary A0535+262/HDE 245770 at different phases of its - 111 d orbital period. This obs... We present the results obtained from extensive near-infrared (IR) spectro- scopic and photometric observations of the Be/X-ray binary A0535+262/HDE 245770 at different phases of its - 111 d orbital period. This observation campaign is part of the monitoring program of selective Be/X-ray binary systems aimed at understanding X-ray and near-IR properties at different orbital phases, especially during the perias- tron passage of the neutron star. The near-IR observations presented here were carried out using the 1.2 m telescope at the Mt. Abu IR Observatory. Though the source was relatively faint for spectroscopic observations with the 1.2 m telescope, we monitored the source closely during the 2011 February-March giant X-ray outburst to primarily investigate whether any drastic changes in the near-IR JHK spectra took place at the periastron passage. Changes of such a striking nature were expected to be detectable in our spectra. Photometric observations of the Be star show a gradual and systematic fading in the JHK light curves since the onset of the X-ray outburst, which could suggest a mild evacuation/truncation of the circumstellar disk of the Be companion. Near-IR spectroscopy of the object shows that the JHK spectra are dominated by the emission lines of hydrogen Brackett and Paschen series and HeI lines at 1.0830, 1.7002 and 2.0585 μm. The presence of all the hydrogen emission lines in the JHK spectra, along with the absence of any significant change in the continuum of the Be companion during X-ray quiescent and X-ray outburst phases, suggests that the near- IR line emitting regions of the disk are not significantly affected during the X-ray outburst. 展开更多
关键词 infrared stars - Be binaries - stars: individual (A0535+262) - tech-niques: spectroscopic
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IRAS F21013-0739:a possible evolutionary successor of an ultraluminous infrared galaxy
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作者 Xian-Min Meng Hong Wu Chen Cao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第4期419-433,共15页
We present a stellar population synthesis study of a type II luminous infrared galaxy, IRAS F21013-0739. Optical images show clear characteristics of a merger remnant. The H-band absolute magnitude is MH = -25.1, whic... We present a stellar population synthesis study of a type II luminous infrared galaxy, IRAS F21013-0739. Optical images show clear characteristics of a merger remnant. The H-band absolute magnitude is MH = -25.1, which is -2 times as luminous as L* galaxies. Stellar populations are obtained through the stellar synthesis code STARLIGHT. We find that it experienced a recent starburst (SB) phase - 100 Myr ago. By reconstructing the ultraviolet-to-optical spectrum, and adopting Calzetti et al. and Leitherer et al.'s extinction curves, we estimate the past infrared (IR) luminosities of the host galaxy and find it may have experienced an ultraluminous infrared galaxy phase which lasted for about 100 Myr. Its i-band absolute magnitude is Mi = -22.463, and its spectral type shows type 2 active galactic nucleus (AGN) characteristics. The mass of the supermassive black-hole is estimated to be MBH = 1.6 × 107 M⊙ (lower- limit). The Eddington ratio Lbol/LEdd is 0.15, which is typical of Palomar-Green (PG) quasars. Both the nuclear SB and AGN contribute to the present IR luminosity budget, and the SB contributes -67%. On the diagram of IR color versus IR/opfical excess, it is located between IR quasars and PG quasars. These results indicate that IRAS F21013-0739 has probably evolved from a ULIRG, and it can possibly evolve into an AGN. 展开更多
关键词 infrared galaxies -- galaxies evolution -- galaxies starburst --galaxies: individual (IRAS F21013-0739) -- galaxies stellar content
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The Case Report on the Effectiveness of Infrared Light on Acid Burn Victim
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作者 Maha Farhina 《Case Reports in Clinical Medicine》 2022年第12期527-533,共7页
Burn injuries are common in Pakistan. However, most people are reluctant to have infrared treatment for their wounds. This study investigated the efficacy of infrared treatment on burn wounds. The procedure involved a... Burn injuries are common in Pakistan. However, most people are reluctant to have infrared treatment for their wounds. This study investigated the efficacy of infrared treatment on burn wounds. The procedure involved a burn victim who had sustained acid burns to the neck and face. Nectrotomy was done to remove dead tissue from the burn wound, and after treatment, Low-Level Light was used to reduce pain and enhance healing in the patient. Initial results showed mild hypertrophic scars, no stiffness. Post-operation therapy included physical training regimens and massage. The patient showed satisfactory results and felt less tightness in neck movements by the following treatment. The article concludes by showing that infrared light promoted repair and regrowth at a cellular level. 展开更多
关键词 infrared Therapy Acid Burns PHOTOBIOMODULATION Low light Laser Therapy Red light
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Mid-to-Far Infrared Spectral Energy Distribution of Galaxies in the Spitzer First Look Survey Field
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作者 Xiao-Qing Wen Hong Wu +1 位作者 Chen Cao Xiao-Yang Xia 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2007年第2期187-198,共12页
We made model fitting to the mid-to-far infrared spectral energy distributions (SEDs) for different categories of galaxies in the main extragalactic field of the Spitzer First Look Survey with the aid of spectroscop... We made model fitting to the mid-to-far infrared spectral energy distributions (SEDs) for different categories of galaxies in the main extragalactic field of the Spitzer First Look Survey with the aid of spectroscopic information from the Sloan Digital Sky Survey. We find that the mid-to-far infrared SEDs of HII galaxies, mixture type galaxies and LINERs can be well fitted by the one-parameter (α) dust model of Dale et al. plus the 13 Gyr dust-free elliptical galaxy model. The statistics of α values indicates that all these galaxies tend to be quiescent, although the HII galaxies are relatively more active than the LINERs. The midinfrared SEDs of absorption galaxies are well fitted simply by the 13 Gyr dust-free elliptical galaxy template, and the near-to-mid infrared SEDs of QSOs can be represented by AGN NGC 5506. 展开更多
关键词 galaxies general - infrared galaxies - galaxies: active - galaxies statistics
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Radio Identifications of Markarian Galaxies and the Correlation between Radio and Far-Infrared Properties
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作者 Shao-Guang Luo Xue-Bing Wu 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2005年第5期448-456,共9页
By checking DSS optical images and NVSS radio images, 782 Markarian galaxies were identified to be NVSS radio sources. A comparison of the radio luminosity at 1.4GHz and the far-infrared (FIR) luminosity for 468 “n... By checking DSS optical images and NVSS radio images, 782 Markarian galaxies were identified to be NVSS radio sources. A comparison of the radio luminosity at 1.4GHz and the far-infrared (FIR) luminosity for 468 “normal” galaxies shows a tight correlation. Most of the Seyfert galaxies and quasars follow the radio-FIR relation deduced from the “normal” galaxy sample, but with a somewhat larger scatter. A total 167 Markarian galaxies, comprising 100 “normal” galaxies, 66 Seyfert galaxies and one quasar, have either excess radio emission or much lower FIR spectral index α(25 μm, 60 μm). These galaxies may be classified as “AGN-powered”. For “normal” galaxies, the average q value (defined as the log ratio between FIR and radio luminosities) is 2.3. There seems a trend for q to slightly decrease with increasing radio luminosity. This may imply that the ongoing active star formation in galaxies with higher radio luminosities is more efficient in heating the cosmic-ray electrons. 展开更多
关键词 galaxies: active - galaxies: Seyfert - galaxies: starburst - radio continuum: galaxies - infrared galaxies
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