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Adaptive Design of Fluorescence Imaging Systems for Custom Resolution, Fields of View, and Geometries
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作者 Roujia Wang Riley J.Deutsch +2 位作者 Enakshi D.Sunassee Brian T.Crouch Nirmala Ramanujam 《Biomedical Engineering Frontiers》 CAS 2023年第1期260-273,共14页
Objective and Impact Statement:We developed a generalized computational approach to design uniform,high-intensity excitation light for low-cost,quantitative fluorescence imaging of in vitro,ex vivo,and in vivo samples... Objective and Impact Statement:We developed a generalized computational approach to design uniform,high-intensity excitation light for low-cost,quantitative fluorescence imaging of in vitro,ex vivo,and in vivo samples with a single device.Introduction:Fluorescence imaging is a ubiquitous tool for biomedical applications.Researchers extensively modify existing systems for tissue imaging,increasing the time and effort needed for translational research and thick tissue imaging.These modifications are applicationspecific,requiring new designs to scale across sample types.Methods:We implemented a computational model to simulate light propagation from multiple sources.Using a global optimization algorithm and a custom cost function,we determined the spatial positioning of optical fibers to generate 2 illumination profiles.These results were implemented to image core needle biopsies,preclinical mammary tumors,or tumor-derived organoids.Samples were stained with molecular probes and imaged with uniform and nonuniform illumination.Results:Simulation results were faithfully translated to benchtop systems.We demonstrated that uniform illumination increased the reliability of intraimage analysis compared to nonuniform illumination and was concordant with traditional histological findings.The computational approach was used to optimize the illumination geometry for the purposes of imaging 3 different fluorophores through a mammary window chamber model.Illumination specifically designed for intravital tumor imaging generated higher image contrast compared to the case in which illumination originally optimized for biopsy images was used.Conclusion:We demonstrate the significance of using a computationally designed illumination for in vitro,ex vivo,and in vivo fluorescence imaging.Applicationspecific illumination increased the reliability of intraimage analysis and enhanced the local contrast of biological features.This approach is generalizable across light sources,biological applications,and detectors. 展开更多
关键词 ILLUMINATION FLUORESCENCE image
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Deep Facial Emotion Recognition Using Local Features Based on Facial Landmarks for Security System
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作者 Youngeun An Jimin Lee +1 位作者 Eunsang Bak Sungbum Pan 《Computers, Materials & Continua》 SCIE EI 2023年第8期1817-1832,共16页
Emotion recognition based on facial expressions is one of the most critical elements of human-machine interfaces.Most conventional methods for emotion recognition using facial expressions use the entire facial image t... Emotion recognition based on facial expressions is one of the most critical elements of human-machine interfaces.Most conventional methods for emotion recognition using facial expressions use the entire facial image to extract features and then recognize specific emotions through a pre-trained model.In contrast,this paper proposes a novel feature vector extraction method using the Euclidean distance between the landmarks changing their positions according to facial expressions,especially around the eyes,eyebrows,nose,andmouth.Then,we apply a newclassifier using an ensemble network to increase emotion recognition accuracy.The emotion recognition performance was compared with the conventional algorithms using public databases.The results indicated that the proposed method achieved higher accuracy than the traditional based on facial expressions for emotion recognition.In particular,our experiments with the FER2013 database show that our proposed method is robust to lighting conditions and backgrounds,with an average of 25% higher performance than previous studies.Consequently,the proposed method is expected to recognize facial expressions,especially fear and anger,to help prevent severe accidents by detecting security-related or dangerous actions in advance. 展开更多
关键词 Facial emotion recognition landmark-based feature extraction ensemble network robustness to the changes in illumination and background dangerous situation detection accident prevention
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Estimation-free spatial-domain image reconstruction of structured illumination microscopy 被引量:1
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作者 Xiaoyan Li Shijie Tu +4 位作者 Yile Sun Yubing Han Xiang Hao Cuifang kuang Xu Liu 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第2期45-58,共14页
Structured illumination microscopy(SIM)achieves super-resolution(SR)by modulating the high-frequency information of the sample into the passband of the optical system and subsequent image reconstruction.The traditiona... Structured illumination microscopy(SIM)achieves super-resolution(SR)by modulating the high-frequency information of the sample into the passband of the optical system and subsequent image reconstruction.The traditional Wiener-filtering-based reconstruction algorithm operates in the Fourier domain,it requires prior knowledge of the sinusoidal illumination patterns which makes the time-consuming procedure of parameter estimation to raw datasets necessary,besides,the parameter estimation is sensitive to noise or aberration-induced pattern distortion which leads to reconstruction artifacts.Here,we propose a spatial-domain image reconstruction method that does not require parameter estimation but calculates patterns from raw datasets,and a reconstructed image can be obtained just by calculating the spatial covariance of differential calculated patterns and differential filtered datasets(the notch filtering operation is performed to the raw datasets for attenuating and compensating the optical transfer function(OTF)).Experiments on reconstructing raw datasets including nonbiological,biological,and simulated samples demonstrate that our method has SR capability,high reconstruction speed,and high robustness to aberration and noise. 展开更多
关键词 Structured illumination microscopy image reconstruction spatial domain digital micromirror device(DMD)
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Intelligent emergency service system based on wireless sensor and actuator networks 被引量:1
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作者 张颖 张军 +2 位作者 宋光明 乔贵方 宋爱国 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期39-44,共6页
An intelligent emergency service( IES) system is designed for indoor environments based on a wireless sensor and actuator network( WSAN) composed of a gateway, sensor nodes, and a multi-robot system( MRS). If th... An intelligent emergency service( IES) system is designed for indoor environments based on a wireless sensor and actuator network( WSAN) composed of a gateway, sensor nodes, and a multi-robot system( MRS). If the MRS receives accident alarm information, the group of robots will navigate to the accident sites and provide corresponding emergency services.According to the characteristics of the MRS, a distributed consensus formation protocol is designed, which can assure that the multiple robots arrive at the accident site in a specified formation. The prototype emergency service system was designed and implemented, and some relevant simulations and experiments were carried out. The results showthat the MRS can successfully provide emergency lighting and failure node replacement services when accidents happen. The effectiveness of the algorithm and the feasibility of the system are verified. 展开更多
关键词 emergency service wireless sensor and actuator network intelligent illumination multi-robot system
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Tomato detection method using domain adaptive learning for dense planting environments
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作者 LI Yang HOU Wenhui +4 位作者 YANG Huihuang RAO Yuan WANG Tan JIN Xiu ZHU Jun 《农业工程学报》 EI CAS CSCD 北大核心 2024年第13期134-145,共12页
This study aimed to address the challenge of accurately and reliably detecting tomatoes in dense planting environments,a critical prerequisite for the automation implementation of robotic harvesting.However,the heavy ... This study aimed to address the challenge of accurately and reliably detecting tomatoes in dense planting environments,a critical prerequisite for the automation implementation of robotic harvesting.However,the heavy reliance on extensive manually annotated datasets for training deep learning models still poses significant limitations to their application in real-world agricultural production environments.To overcome these limitations,we employed domain adaptive learning approach combined with the YOLOv5 model to develop a novel tomato detection model called as TDA-YOLO(tomato detection domain adaptation).We designated the normal illumination scenes in dense planting environments as the source domain and utilized various other illumination scenes as the target domain.To construct bridge mechanism between source and target domains,neural preset for color style transfer is introduced to generate a pseudo-dataset,which served to deal with domain discrepancy.Furthermore,this study combines the semi-supervised learning method to enable the model to extract domain-invariant features more fully,and uses knowledge distillation to improve the model's ability to adapt to the target domain.Additionally,for purpose of promoting inference speed and low computational demand,the lightweight FasterNet network was integrated into the YOLOv5's C3 module,creating a modified C3_Faster module.The experimental results demonstrated that the proposed TDA-YOLO model significantly outperformed original YOLOv5s model,achieving a mAP(mean average precision)of 96.80%for tomato detection across diverse scenarios in dense planting environments,increasing by 7.19 percentage points;Compared with the latest YOLOv8 and YOLOv9,it is also 2.17 and 1.19 percentage points higher,respectively.The model's average detection time per image was an impressive 15 milliseconds,with a FLOPs(floating point operations per second)count of 13.8 G.After acceleration processing,the detection accuracy of the TDA-YOLO model on the Jetson Xavier NX development board is 90.95%,the mAP value is 91.35%,and the detection time of each image is 21 ms,which can still meet the requirements of real-time detection of tomatoes in dense planting environment.The experimental results show that the proposed TDA-YOLO model can accurately and quickly detect tomatoes in dense planting environment,and at the same time avoid the use of a large number of annotated data,which provides technical support for the development of automatic harvesting systems for tomatoes and other fruits. 展开更多
关键词 PLANTS MODELS domain adaptive tomato detection illumination variation semi-supervised learning dense planting environments
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ED-Ged:Nighttime Image Semantic Segmentation Based on Enhanced Detail and Bidirectional Guidance
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作者 Xiaoli Yuan Jianxun Zhang +1 位作者 Xuejie Wang Zhuhong Chu 《Computers, Materials & Continua》 SCIE EI 2024年第8期2443-2462,共20页
Semantic segmentation of driving scene images is crucial for autonomous driving.While deep learning technology has significantly improved daytime image semantic segmentation,nighttime images pose challenges due to fac... Semantic segmentation of driving scene images is crucial for autonomous driving.While deep learning technology has significantly improved daytime image semantic segmentation,nighttime images pose challenges due to factors like poor lighting and overexposure,making it difficult to recognize small objects.To address this,we propose an Image Adaptive Enhancement(IAEN)module comprising a parameter predictor(Edip),multiple image processing filters(Mdif),and a Detail Processing Module(DPM).Edip combines image processing filters to predict parameters like exposure and hue,optimizing image quality.We adopt a novel image encoder to enhance parameter prediction accuracy by enabling Edip to handle features at different scales.DPM strengthens overlooked image details,extending the IAEN module’s functionality.After the segmentation network,we integrate a Depth Guided Filter(DGF)to refine segmentation outputs.The entire network is trained end-to-end,with segmentation results guiding parameter prediction optimization,promoting self-learning and network improvement.This lightweight and efficient network architecture is particularly suitable for addressing challenges in nighttime image segmentation.Extensive experiments validate significant performance improvements of our approach on the ACDC-night and Nightcity datasets. 展开更多
关键词 Night driving semantic segmentation nighttime image processing adverse illumination differentiable filters
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Effect of Light Quality and Intensity on N_2O and NO_X(NO, NO_2)Emissions from Rice Phyllosphere and Roots at Tillering Stage in a Liquid Culture Medium System
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作者 徐胜光 李冰 +5 位作者 刘佳妮 陈泽斌 余磊 赵凤 耿开友 王定康 《Agricultural Science & Technology》 CAS 2016年第3期633-641,共9页
[Objective] N2Oand NOX(NO, NO2) are important nitrogen oxides gases(NOGs) in paddy fields, and rice plants play important roles in NOG emissions in paddy fields. However, the source of NOG emissions from rice phyl... [Objective] N2Oand NOX(NO, NO2) are important nitrogen oxides gases(NOGs) in paddy fields, and rice plants play important roles in NOG emissions in paddy fields. However, the source of NOG emissions from rice phyllosphere and roots and their relationship to light quality and intensity still remain unclear. In this study, the relationship between light quality, intensity and N2 O, NOX(NO, NO2) emissions from rice phyllosphere and roots at tillering stage was investigated to clarify the contribution of rice plants to N2Oand NOX(NO, NO2) emissions and analyze the mechanism of light control, aiming at providing a scientific basis for revealing how light-control technology affects NOG emissions from rice at tillering stage in paddy fields. [Method] In this study, nitrogen content was controlled by a hydroponic system. A small electric incubator was used for light control. A simultaneous determination was designed to investigate the effect of different weak light qualities(yellow, green, white, red and blue lights) and intensities(dark, 0 lx; very weak, 2 000lx; weak, 4 000 lx; moderate, 6 000 lx; strong, 8 000 lx) on N2Oand NOXemissions from rice phyllosphere and roots at tillering stage in a liquid culture medium system. N2Oconcentration in air samples was determined by gas chromatography within 12 h, and NOX(NO, NO2) concentration was analyzed using 42 i NO- NO2-NOXgas analyzer. [Result] The results showed that:(1) Under a constant nitrogen condition(NH4NO3-N, 90 mg/L) when rice seedlings were treated with moderate(6 000lx) and strong(8 000 lx) light, the average emission rate of N2Oand NO from rice phyllosphere at tillering stage was 27.08, 32.33 μg/(pot·h) and 0.114, 0.057 μg/(pot·h),respectively, accounting for 57.38%, 58.65% and 9.65%, 4.52% of the total release of N2Oand NO from the whole rice plant, respectively. It implicated that rice phyllosphere is an important source of N2Oemission at tillering stage in paddy fields.(2)When rice seedlings were treated with yellow, green, white, red and blue LED lights under a constant light intensity(1 600 lx), the average emission rate of N2Ofrom rice phyllosphere was 6.83, 9.40, 9.73, 2.82 and 4.08 μg/(pot·h), respectively. Compared with green and yellow LED lights, N2Oemission from rice phyllosphere and roots at tillering stage was inhibited markedly by red(3 000 lx) and blue(2 500 lx)LED lights(P0.01). In addition, NO emission from rice phyllosphere was enhanced significantly by white and red LED lights, while NO emissions from rice phyllosphere and roots were inhibited by blue light synchronously. Nevertheless, no evident NO2 emission from rice phyllosphere and roots was detected under the same condition.(3) Within the range of 0-8 000 lx, NO and N2Oemissions from rice roots and N2Oemission from rice phyllosphere increased with the enhancement of light intensity. In contrast, NO emission from rice phyllosphere was inhibited remarkably by moderate(6 000 lx) and strong(8 000 lx) light(P〈 0.01). [Conclusion] Rice seedlings mainly exhibited net emissions of NO2 from the phyllosphere and roots.N2Oand NOX(NO, NO2) emissions from rice phyllosphere and roots at tillering stage could be inhibited by adjusting the composition of visible light(synchronously increasing the proportions of red and blue lights) and appropriately controlling daytime light intensity. 展开更多
关键词 ILLUMINATION RICE N2O NOX(NO NO2) Emission
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Efficacy and safety of Usights UC100 illuminated microcatheter in microcatheter-assisted trabeculotomy
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作者 Shuo Yu Ke Xu Chun Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期272-277,共6页
AIM:To evaluate the efficacy and safety of Usights UC100 illuminated microcatheter in microcatheter-assisted trabeculotomy(MAT).METHODS:Totally 10 eyes of 10 patients with primary open angle glaucoma(POAG)who underwen... AIM:To evaluate the efficacy and safety of Usights UC100 illuminated microcatheter in microcatheter-assisted trabeculotomy(MAT).METHODS:Totally 10 eyes of 10 patients with primary open angle glaucoma(POAG)who underwent MAT facilitated by Usights UC100(5 eyes)or iTrack(5 eyes)were reviewed.The success of this surgery was defined as intraocular pressure(IOP)<22 mm Hg with>30%reduction,without oral glaucoma medications,or additional glaucoma surgery.RESULTS:The mean pre-operative IOP was 25.38±10.22 mm Hg in the Usights UC100 group and 19.98±3.87 mm Hg in the iTrack group.MAT was achieved in all eyes in both groups.The success rates for the Usights UC100 group and iTrack groups were in all and 4 eyes,respectively.Both microcatheters produced a statistically significant reduction in IOP,and eyes using Usights UC100 achieved a lower IOP than the iTrack group at 3mo followup(12.58±1.52 and 14.84±1.89 mm Hg,respectively),but no statistical significance was there.No severe side effects were observed in either group.CONCLUSION:MAT using Usights UC100 or iTrack both achieve significant pressure reduction in cases of POAG,and Usights UC100 is as safe as iTrack. 展开更多
关键词 illuminated microcatheter microcatheterassisted trabeculotomy primary open angle glaucoma
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Numerical Simulation of Super-Resolution Structured Illumination Microscopy (SIM) Using Heintzmann-Cremer Algorithm with Non-Continuous Spatial Frequency Support
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作者 Mesfin Woldeyohannes William McCray Weiguo Yang 《Optics and Photonics Journal》 2024年第5期75-90,共16页
We report a comprehensive numerical study of super resolution (SR) structured illumination microscopy (SIM) utilizing the classic Heintzmann-Cremer SIM process and algorithm. In particular, we investigated the impact ... We report a comprehensive numerical study of super resolution (SR) structured illumination microscopy (SIM) utilizing the classic Heintzmann-Cremer SIM process and algorithm. In particular, we investigated the impact of the diffraction limit of the underlying imaging system on the optimal SIM grating frequency that can be used to obtain the highest SR enhancement with non-continuous spatial frequency support. Besides confirming the previous theoretical and experimental work that SR-SIM can achieve an enhancement close to 3 times the diffraction limit with grating pattern illuminations, we also observe and report a series of more subtle effects of SR-SIM with non-continuous spatial frequency support. Our simulations show that when the SIM grating frequency exceeds twice that of the diffraction limit, the higher SIM grating frequency can help achieve a higher SR enhancement for the underlying imaging systems whose diffraction limit is low, though this enhancement is obtained at the cost of losing resolution at some lower resolution targets. Our simulations also show that, for underlying imaging systems with high diffraction limits, however, SR-SIM grating frequencies above twice the diffraction limits tend to bring no significant extra enhancement. Furthermore, we observed that there exists a limit grating frequency above which the SR enhancement effect is lost, and the reconstructed images essentially have the same resolution as the one obtained directly from the underlying imaging system without using the SIM process. 展开更多
关键词 Structured Illumination Microscopy Super Resolution Imaging Spatial Frequency Support Diffraction Limit
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Alerting effects of light in healthy individuals: a systematic review and meta-analysis 被引量:3
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作者 Yi-Man Mu Xiao-Dan Huang +4 位作者 Sui Zhu Zheng-Fang Hu Kwok-Fai So Chao-Ran Ren Qian Tao 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第9期1929-1936,共8页
Light plays an essential role in psychobiological and psychophysiological processes,such as alertness.The alerting effect is influenced by light characteristics and the timing of interventions.This meta-analysis is th... Light plays an essential role in psychobiological and psychophysiological processes,such as alertness.The alerting effect is influenced by light characteristics and the timing of interventions.This meta-analysis is the first to systematically review the effect of light intervention on alertness and to discuss the optimal protocol for light intervention.In this meta-analysis,registered at PROSPERO(Registration ID:CRD42020181485),we conducted a systematic search of the Web of Science,PubMed,and PsycINFO databases for studies published in English prior to August 2021.The outcomes included both subjective and objective alertness.Subgroup analyses considered a variety of factors,such as wavelength,correlated color temperature(CCT),light illuminance,and timing of interventions(daytime,night-time,or all day).Twenty-seven crossover studies and two parallel-group studies were included in this meta-analysis,with a total of 1210 healthy participants(636(52%)male,mean age 25.62 years).The results revealed that light intervention had a positive effect on both subjective alertness(standardized mean difference(SMD)=-0.28,95%confidence interval(CI):-0.49 to-0.06,P=0.01)and objective alertness in healthy subjects(SMD=-0.34,95%CI:-0.68 to-0.01,P=0.04).The subgroup analysis revealed that cold light was better than warm light in improving subjective alertness(SMD=-0.37,95%CI:-0.65 to-0.10,P=0.007,I2=26%)and objective alertness(SMD=-0.36,95%CI:-0.66 to-0.07,P=0.02,I2=0).Both daytime(SMD=-0.22,95%CI:-0.37 to-0.07,P=0.005,I2=74%)and night-time(SMD=-0.32,95%CI:-0.61 to-0.02,P=0.04,I2=0)light exposure improved subjective alertness.The results of this meta-analysis and systematic review indicate that light exposure is associated with significant improvement in subjective and objective alertness.In addition,light exposure with a higher CCT was more effective in improving alertness than light exposure with a lower CCT.Our results also suggest that both daytime and night-time light exposure can improve subjective alertness. 展开更多
关键词 correlated color temperature ILLUMINANCE LIGHT META-ANALYSIS objective alertness subjective alertness time of light intervention wavelength
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Real-time Audio &Video Transmission System Based on Visible Light Communication 被引量:3
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作者 Yingjie He Liwei Ding +1 位作者 Yuxian Gong Yongjin Wang 《Optics and Photonics Journal》 2013年第2期153-157,共5页
With the increasing popularity of solid sate lighting devices, Visible Light Communication (VLC) is globally recognized as an advanced and promising technology to realize short-range, high speed as well as large capac... With the increasing popularity of solid sate lighting devices, Visible Light Communication (VLC) is globally recognized as an advanced and promising technology to realize short-range, high speed as well as large capacity wireless data transmission. In this paper, we propose a prototype of real-time audio and video broadcast system using inexpensive commercially available light emitting diode (LED) lamps. Experimental results show that real-time high quality audio and video with the maximum distance of 3 m can be achieved through proper layout of LED sources and improvement of concentration effects. Lighting model within room environment is designed and simulated which indicates close relationship between layout of light sources and distribution of illuminance. 展开更多
关键词 VISIBLE LIGHT Communications LED REAL-TIME Video and AUDIO BROADCAST system LIGHT Source Arrangement ILLUMINANCE Distribution
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Detection and Ranging System of Flight Aid Lights 被引量:1
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作者 YU Zhi-jing WANG Qiang 《Semiconductor Photonics and Technology》 CAS 2007年第1期20-24,共5页
Dynamic detection based on optics sensors and ranging radars is a new method to detect the luminous intensity of flight aid lights. The optics sensors can get the illumination information of each light, the ranging ra... Dynamic detection based on optics sensors and ranging radars is a new method to detect the luminous intensity of flight aid lights. The optics sensors can get the illumination information of each light, the ranging radar gets the distance information, and then data amalgamation technology is used to compute the luminous intensity of each light. A method to modify the errors of this dynamic detection system is presented. It avoids the accumulation error and measurement carrier’s excursion error by using peak value detection based on optics sensors to estimate the accurate position of each light, then to modify the lights’ lengthways distance information and transverse position information. The performance of the detection and ranging system is validated by some experiments and shown in pictures. 展开更多
关键词 luminous intensity dynamic detection ILLUMINATION optics sensor
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New LED light source system with uniform illumination for line-scan CCD imaging systems
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作者 张莲莲 黄庆梅 +3 位作者 李心怡 胡维贵 刘南渤 陆爱民 《Journal of Beijing Institute of Technology》 EI CAS 2016年第4期571-574,共4页
A system with uniform light reflection in the inner surface within a horizontal 2/3 cylindrical structure for line-scan CCD of the print testing was designed. The design was based on diffuse reflection uniformity of t... A system with uniform light reflection in the inner surface within a horizontal 2/3 cylindrical structure for line-scan CCD of the print testing was designed. The design was based on diffuse reflection uniformity of the integrating sphere and requirement of the strip uniform illumination region. This system was called dome light. White light LED array light sources were used for uniform illumi- nation. The LEDs were filtrated to composite array light source based on coefficient of variation of a single LED. The standard white board and SG color checkers were used in the line-scan CCD imaging experiments under the dome light and ordinary illumination light source. The average color difference (AE) of SG color checkers in CIELAB space was 2. 091 under the dome light and 2. 286 under ordinary illumination light source respectively. Experimental results indicate that the dome light can satisfy illumination uniformity and color rendering consistency for line-scan CCD and provide a standard light source for uniform calibration of different cameras. 展开更多
关键词 line-scan CCD uniform illumination white light LED coefficient of variation arraylight source color difference
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Brief Introduction ofChina Illuminating Engineering Journal
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《照明工程学报》 2005年第S1期101-,共1页
关键词 CIE Brief Introduction ofChina illuminating Engineering Journal
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Spectrum Illumination for 3-D Surface Imaging System
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作者 XUZhi-hai FENGHua-jun 《Semiconductor Photonics and Technology》 CAS 2001年第2期70-75,共6页
A method using spectrum illumination to reconstruct 3-D object image is a new concept in the field of computer vision. The design of optical illumination system is crucial in this method. Several ways to achieve multi... A method using spectrum illumination to reconstruct 3-D object image is a new concept in the field of computer vision. The design of optical illumination system is crucial in this method. Several ways to achieve multi-color spectrum illumination are discussed. A prism illumination system is designed by means of aligning symmetrically the prism at the mid-wavelength (n d=1.806 274) of light path and using reflection collimating lens, cylindrical expending lens and two optical shutters. The relations between deviation angles and light wavelengths are given, and some 3-D reconstruction results are presented. 展开更多
关键词 3-D imaging Spectrum illumination Computer vision
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Reflector Design Method for Rotational Uniform Illuminance System with LED
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作者 ZHANG Qi-hui WANG Hong JI Ling-ling 《Semiconductor Photonics and Technology》 CAS 2009年第3期163-166,共4页
Based on nonimaging design method, uniform illuminance systems with LED source were developed to create a uniform illuminated circular region with a desired size in a screen at a prescribed place. By using ray-tracing... Based on nonimaging design method, uniform illuminance systems with LED source were developed to create a uniform illuminated circular region with a desired size in a screen at a prescribed place. By using ray-tracing software based on Monte-Carlo method, the simulation results show that in the illuminated region the luminous uniformity is higher than 90%. 展开更多
关键词 semiconductor lighting nonimaging optics uniform illuminance system
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Uniformly Illuminated Efficient Daylighting System
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作者 Irfan Ullah Seoyong Shin 《Smart Grid and Renewable Energy》 2013年第2期161-166,共6页
Different approaches have been introduced for the daylighting system to reduce energy consumption, but they were not populated due to complex, high cost, and insufficient designs. There has been a recent problem in ac... Different approaches have been introduced for the daylighting system to reduce energy consumption, but they were not populated due to complex, high cost, and insufficient designs. There has been a recent problem in achieving uniform distribution of sunlight at a destination deep inside the building. Therefore, we propose a system to achieve high illumination by illuminating the surface of the absorber (optical fibers) uniformly. To capture sunlight, parabolic reflector and Fresnel lens are used. Different reflectors and lenses are considered, compared, and investigated to direct uniform light, which solves the heat problem, into the optical fibers. In addition, this study includes comparison between fiber-based daylighting systems. The proposed system has been verified through simulation and experimental results. 展开更多
关键词 UNIFORM ILLUMINATION DAYLIGHTING system Optical Fiber Solar CONCENTRATOR
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Distributed Intelligent Lighting System by Performing New Model for Illuminance and Color Temperature in the Workplace
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作者 Mohammed Hajjaj Mitsunori Miki 《Intelligent Control and Automation》 2019年第1期1-12,共12页
A new approach has been proposed to improve the performance of the in-telligent lighting system by estimating personal illuminance and desired color temperature at the workplace. We are considering the problem of usin... A new approach has been proposed to improve the performance of the in-telligent lighting system by estimating personal illuminance and desired color temperature at the workplace. We are considering the problem of using the sensing devices manually for the intelligent lighting system. The lighting control system has not become useful without sensing devices to measure the provided illuminance and color temperature. In this paper, we have used the property of light for the color temperature to estimate the level of color temperature for each user at the workplace. The new method will give personal illuminance for each user at the workplace and decrease the power consumption of the environment as well. As a result, the proposed method of the intelligent lighting system has realized the target of illuminance and color temperature for each user at the workplace by adapting dimming levels using illuminance sensing information for each user. Thus, the energy of the workplace has reduced by using a distributed luminance to realize the target for each user. 展开更多
关键词 Intelligent Lighting system ILLUMINANCE CORRELATED Color Temperature CHROMA METER Automated Optimization Method
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Improvement of the Silicon Solar Cell Performance by Integration of an Electric Field Source in the Solar Cell or Solar Module System
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作者 Adama Ouedraogo Serge Dimitri Y. B. Bazyomo +2 位作者 Salifou Ouedraogo Abdoul Razakou Dieudonné Joseph Bathiebo 《Smart Grid and Renewable Energy》 2018年第12期285-298,共14页
This manuscript is about a theoretical modelling of conversion efficiency improvement of a typical polycrystalline Si solar cell in 1D assumptions. The improvement is brought by the increase of the collection of the m... This manuscript is about a theoretical modelling of conversion efficiency improvement of a typical polycrystalline Si solar cell in 1D assumptions. The improvement is brought by the increase of the collection of the minority carriers charge in excess. This increase is the consequence of the influence of an electric field provided by the use of the open circuit photovoltage of another silicon solar cell. We assume that it is integrated two silicon solar cells to the system. The first solar cell provides the open circuit photovoltage which is connected to two aluminum planar armatures creating a planar capacitor. The second solar cell is placed under the uniform electric field created between the two aluminum armatures. This work has shown an improvement of the output electric power leading to the increase of the conversion efficiency. We observe an increase of 0.7% of the conversion efficiency of the second silicon solar cell. 展开更多
关键词 Open Circuit PHOTOVOLTAGE Planar CAPACITOR ELECTRIC Field CONVERSION Efficiency MONOCHROMATIC ILLUMINATION and Silicon Solar Cell
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Particularities in the Design of Underwater Lighting Systems
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作者 Elena Serea Nelca Roco 《Journal of Civil Engineering and Architecture》 2022年第8期420-424,共5页
The light propagation medium determines the way in which the light is perceived by the observer’s eye.As water is a good transmitter and diffuser,when designing an underwater lighting system there are features in add... The light propagation medium determines the way in which the light is perceived by the observer’s eye.As water is a good transmitter and diffuser,when designing an underwater lighting system there are features in addition to be analyzed,which complement the common considerations for usual artificial lighting systems.The paper aims to present in detail a luminaire calculation method for 4 different types of pools with clear and transparent water(three recreational swimming pools of same size and depth,situated in interior and exterior and one small training interior swimming pool having the size of a quarter of professional competition type).There is a proposed formula for determining the number of floodlights,depending on water surface,immersion depth,average illumination on surface,uniformity,luminous flux of the light source and a water light distribution coefficient.There are highlighted specific variable parameters to be taken into account to meet the visual requirements mentioned in regulations.Depending on the application,visual comfort can be easily disturbed by the changing criteria of ambiance or surroundings,thus diminishing the visual performance. 展开更多
关键词 LIGHT POOL ILLUMINANCE GLARE distribution coefficient
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