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Introduction to Special Issue on Fluorescent Probes for Optical Imaging and Biosensing
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作者 Changfeng Wu Chenguang Wang Wei Chen 《Journal of Innovative Optical Health Sciences》 2025年第3期1-2,共2页
Fluorescent probes have revolutionized optical imaging and biosensing by enabling real-time visualization, quantification, and tracking of biological processes at molecular and cellular levels. These probes, ranging f... Fluorescent probes have revolutionized optical imaging and biosensing by enabling real-time visualization, quantification, and tracking of biological processes at molecular and cellular levels. These probes, ranging from organic dyes to genetically encoded proteins and nanomaterials, provide unparalleled specificity, sensitivity, and multiplexing capabilities. However, challenges such as brightness, photobleaching, biocompatibility, and emission range continue to drive innovation in probe design and application. This special issue, comprising four review papers and seven original research studies, highlights cutting-edge advancements in fluorescent probe technologies and their transformative roles in super-resolution imaging, in vivo diagnostics, and cancer therapeutics. 展开更多
关键词 super resolution imaging organic dyes BIOSENSING genetically encoded proteins optical imaging tracking biological processes fluorescent probes
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Progress of Optically Encoded Microspheres for Multiplexed Assays
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作者 朱莹 徐宏 古宏晨 《Journal of Shanghai Jiaotong university(Science)》 EI 2014年第5期521-530,共10页
New initiatives put forward by clinical diagnosis require the development of technologies for high throughput screening(HTS) of multiple analytes. Suspension arrays have great advantages over the planar arraybased mul... New initiatives put forward by clinical diagnosis require the development of technologies for high throughput screening(HTS) of multiple analytes. Suspension arrays have great advantages over the planar arraybased multiplexing assays, and the encoded bead is the key for providing multiplexing capability. Among various encoding strategies, optically encoded microspheres have been widely used while the number of codes is still limited. This review discusses the progress of optical encoding strategy from mainly three aspects, namely organic dyes, quantum dots(QDs) and surface-enhanced Raman scattering(SERS) active substrates. Emphases are put up on describing how these optical encoded microbeads are manufactured and the merits and demerits of different encoding materials are compared. 展开更多
关键词 MULTIPLEXING suspension arrays optically encoded microspheres fluorescent dyes quantum dots(QDs) surface-enhanced Raman scattering(SERS)
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Designs of All-Optical Higher-Order Signed-Digit Adders Using Polarization-Encoded Based Terahertz-Optical-Asymmetric-Demultiplexer (TOAD)
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作者 Ali Hajjiah Abdullah Alqallaf Abdallah Cherri 《Optics and Photonics Journal》 2014年第6期113-128,共16页
Various designed circuits for multiple-valued all-optical arithmetic are demonstrated. The terahertz-optical-asymmetric-demultiplexer (TOAD) switch is used as the basic structure unit in the proposed circuits due to i... Various designed circuits for multiple-valued all-optical arithmetic are demonstrated. The terahertz-optical-asymmetric-demultiplexer (TOAD) switch is used as the basic structure unit in the proposed circuits due to its compact size, thermal stability, and low power operation. The designs of trinary and quaternary signed-digit numbers based adders are presented using different polarized states of light. These proposed polarization-encoded based adders use much less switches and their speeds are higher than the intensity-encoded counterparts. Further, it will be shown that one of the proposed trinary signed-digit adders is twice as fast as a recently reported modified signed-digit adder. 展开更多
关键词 Multiple-Valued Signed-Digit ALL-optical Gates Polarization-encoding Terahertz-optical-Asymmetric-Demultiplexer (TOAD)
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Application of Instantaneous Rotational Speed to Detect Gearbox Faults Based on Double Encoders 被引量:2
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作者 Lin Liang Fei Liu +2 位作者 Xiangwei Kong Maolin Li Guanghua Xu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第1期54-64,共11页
Considerable studies have been carried out on fault diagnosis of gears, with most of them concentrated on conventional vibration analysis. However, besides the complexity of gear dynamics, the diagnosis results in ter... Considerable studies have been carried out on fault diagnosis of gears, with most of them concentrated on conventional vibration analysis. However, besides the complexity of gear dynamics, the diagnosis results in terms of vibration signal are easily misjudged owing to the interference of sensor position or other components. In this paper, an alternative gearbox fault detection method based on the instantaneous rotational speed is proposed because of its advantages over vibration analysis. Depending on the timer/counter-based method for the pulse signal of the optical encoder, the varying rotational speed can be obtained e ectively. Owing to the coupling and meshing of gears in transmission, the excitations are the same for the instantaneous rotational speed of the input and output shafts. Thus, the di erential signal of instantaneous rotational speeds can be adopted to eliminate the e ect of the interference excitations and extract the associated feature of the localized fault e ectively. With the experiments on multistage gearbox test system, the di erential signal of instantaneous speeds is compared with other signals. It is proved that localized faults in the gearbox generate small angular speed fluctuations, which are measurable with an optical encoder. Using the di erential signal of instantaneous speeds, the fault characteristics are extracted in the spectrum where the deterministic frequency component and its harmonics corresponding to crack fault characteristics are displayed clearly. 展开更多
关键词 Instantaneous ROTATIONAL speed optical encoder Localized fault MULTISTAGE GEARBOX
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Deep-learning-based ciphertext-only attack on optical double random phase encryption 被引量:11
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作者 Meihua Liao Shanshan Zheng +4 位作者 Shuixin Pan Dajiang Lu Wenqi He Guohai Situ Xiang Peng 《Opto-Electronic Advances》 SCIE 2021年第5期12-23,共12页
Optical cryptanalysis is essential to the further investigation of more secure optical cryptosystems.Learning-based at-tack of optical encryption eliminates the need for the retrieval of random phase keys of optical e... Optical cryptanalysis is essential to the further investigation of more secure optical cryptosystems.Learning-based at-tack of optical encryption eliminates the need for the retrieval of random phase keys of optical encryption systems but it is limited for practical applications since it requires a large set of plaintext-ciphertext pairs for the cryptosystem to be at-tacked.Here,we propose a two-step deep learning strategy for ciphertext-only attack(COA)on the classical double ran-dom phase encryption(DRPE).Specifically,we construct a virtual DRPE system to gather the training data.Besides,we divide the inverse problem in COA into two more specific inverse problems and employ two deep neural networks(DNNs)to respectively learn the removal of speckle noise in the autocorrelation domain and the de-correlation operation to retrieve the plaintext image.With these two trained DNNs at hand,we show that the plaintext can be predicted in real-time from an unknown ciphertext alone.The proposed learning-based COA method dispenses with not only the retrieval of random phase keys but also the invasive data acquisition of plaintext-ciphertext pairs in the DPRE system.Numerical simulations and optical experiments demonstrate the feasibility and effectiveness of the proposed learning-based COA method. 展开更多
关键词 optical encryption random phase encoding ciphertext-only attack deep learning
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PERFORMANCE ANALYSIS AND SIMULATION OF OCDMA SYSTEM BASED ON FBGs ENCODER/DECODER
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作者 Li Chuanqi Sun Xiaohan Je-Myung Jeong 《Journal of Electronics(China)》 2005年第6期663-670,共8页
The encoding/decoding scheme based on Fiber Bragg Grating (FBG) for Optical Code Division Multiple Access (OCDMA) system is analyzed and the whole process from transmitting end to receiving end is researched in detail... The encoding/decoding scheme based on Fiber Bragg Grating (FBG) for Optical Code Division Multiple Access (OCDMA) system is analyzed and the whole process from transmitting end to receiving end is researched in detail. The mathematical mode including signal transmission, summing, receiving and recovering are established respectively. One of the main sources of Bit Error Rate (BER) of OCDMA system based on FBGs is the unevenness of signal power spectrum, which leads to the chip powers unequal with each other. The Signal to Interfere Ratio (SIR) and BER performance of the system are studied and simulated at the case with uneven distribution of chips' powers. 展开更多
关键词 optical Code Division Multiple Access (OCDMA) Fiber Bragg Grating (FBG) optical encoder/decoder
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Performance Analysis of Multiple User Optical Code Division Multiple Access
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作者 Himanshu Monga R. S. Kaler 《Optics and Photonics Journal》 2014年第2期21-25,共5页
In this paper, we discuss and analyze an optical code division multiple access for multiple user system. Media access control implementation has been considered. For fulfilling the huge need of bandwidth services, tec... In this paper, we discuss and analyze an optical code division multiple access for multiple user system. Media access control implementation has been considered. For fulfilling the huge need of bandwidth services, technology tends to move to optical networks and three major optical systems come into existence. Code division of the optical network is most used and real concept interacted with users up to this time. Optical code division multiple access provides complete spectrum to each and every user for the time of accessing the channel. In the paper, we have proposed network architecture with optical encoder and decoder along with optical code translator which is supporting multiple user systems. We integrate the code translator with encoding and decoding of optical code to use the optical network at full extent and present the simulation validation results of 6 Gb/s 3-hop transmission by use of proposed architecture. Further, we have implemented experimentation with 6 users 3 Gb/s optical code division multiple access network. Through simulation structure, it is shown that the combination of encoding with EDFA in multiple user environment system provides improvement in bit error rate and also improves the multiple access interference. With increase of users in the network, MAI value increases and our proposed scheme controls interference in the network. 展开更多
关键词 optical Code DIVISION MULTIPLE ACCESS Strong INTERFERENCE WEAK INTERFERENCE Bit Error Rate optical encoding Laser Diode Source MULTIPLE ACCESS INTERFERENCE
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Development of High-precision Rotary Encoder Using Semiconductor Laser
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作者 MA Hong CHE Ying LI Zhaohui(Changchun Institute of Optics and Fine Mechanics, Changchun 130022, CHN) 《Semiconductor Photonics and Technology》 CAS 1996年第3期204-209,共6页
In this paper, the operation principle of laser rotary encoders is expounded and the optical quadruple frequency technology used in laser rotary encoders is explained, and the design idea of optical system in φ66 mm ... In this paper, the operation principle of laser rotary encoders is expounded and the optical quadruple frequency technology used in laser rotary encoders is explained, and the design idea of optical system in φ66 mm laser rotary encoder is mainly introduced, as well as the choice of principal devices. 展开更多
关键词 Laser Rotary encoder Doppler Effect optical Quadruple Frequency Diffraction Circular Grating Beat Frequency Interference
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Human-face Recognition by use of an Incoherent Optical System
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作者 成罡 《High Technology Letters》 EI CAS 1997年第2期18-21,共4页
In this paper a simple scheme for optical implementation of human-face recognition with only an incoherent optical correlator is presented. The system uses complementary-encoding hit-or-miss transform method to improv... In this paper a simple scheme for optical implementation of human-face recognition with only an incoherent optical correlator is presented. The system uses complementary-encoding hit-or-miss transform method to improve the performance of the standard correlator. According to this method, a compact optical system for human-face optical recognition is bult up. In the face library 200 photographs are stored and the recognition speed of the system is 10 frames per second. The accuracy of recognition is more than 90 percent. The system has good fault-tolerance ability for the pictures with rotation distortion, Gauss noise disturbance or information losing. 展开更多
关键词 Hit-or-miss TRANSFORM Complementary-encoding optical PATTERN recognition
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基于时分复用-曼彻斯特编码的水下无线光通信系统设计
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作者 顾韩彬 周田华 +4 位作者 范婷威 胡谷雨 刘继桥 张大伟 曾令楠 《光通信技术》 北大核心 2026年第1期22-24,共3页
为解决水下无线光通信系统中信号起伏对解调造成的干扰以及大功率激光二极管(LD)带宽受限的问题,设计一种基于时分复用与曼彻斯特编码的水下无线光通信系统,并通过在搭载高功率LD与高灵敏光电探测器(PD)的通信系统中开展对比实验,分析... 为解决水下无线光通信系统中信号起伏对解调造成的干扰以及大功率激光二极管(LD)带宽受限的问题,设计一种基于时分复用与曼彻斯特编码的水下无线光通信系统,并通过在搭载高功率LD与高灵敏光电探测器(PD)的通信系统中开展对比实验,分析了有无时分复用结合的曼彻斯特编码在信号质量、误码率方面的差异。实验结果表明:采用该系统可在等效100 m传输距离下实现50 Mb/s的通信速率,平均误码率降至9.509×10^(-5),相较于无复用系统提升约一个数量级,显著提升了系统的传输可靠性。 展开更多
关键词 水下无线光通信 时分复用 曼彻斯特编码
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Polarization-controlled tri-state optical modulation in Au-ITO heterostructured metasurfaces via plasmon-induced hot electron injection
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作者 Zhihao Chen Renxian Gao +6 位作者 Yongjun Zhang Yaxin Wang Jiahong Wen Wenbin Chen Xurong Lin Ming-De Li Xiaoyu Zhao 《Nano Research》 2026年第2期1056-1062,共7页
Metal-semiconductor plasmonic metasurfaces enable precise optical field manipulation at the subwavelength scale;however,most existing designs rely on external fields and exhibit only binary responses,thereby restricti... Metal-semiconductor plasmonic metasurfaces enable precise optical field manipulation at the subwavelength scale;however,most existing designs rely on external fields and exhibit only binary responses,thereby restricting the realization of multistate logic operations.Here,we present an in-situ polarization-controlled approach based on an Au-indium tin oxide(ITO)bilayer nanocrescent with a Schottky heterojunction for achieving polarization-dependent tristate optical modulation.Polarization-selective excitation of distinct localized plasmon modes facilitates directional hot-electron injection across the Au-ITO interface,thereby producing three distinct programmable states—positive,zero,and negative—at a single detection wavelength.This symmetric bilayer design is applicable to other metal-semiconductor composites and offers generalizable design principles for ternary logic,multistate optical encoding,and ultrafast photonic information processing.The proposed concept is validated through both experimental measurements and numerical simulations. 展开更多
关键词 HOT-ELECTRON PLASMON optical encoding metal-semiconductor metasurfaces ULTRAFAST
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Hybrid WDMA/OCDM system with the capability of encoding multiple wavelength channels by employing one encoder and one corresponding optical code 被引量:4
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作者 陈荷 肖石林 +2 位作者 朱敏 史杰 毕美华 《Chinese Optics Letters》 SCIE EI CAS CSCD 2010年第8期745-748,共4页
A hybrid wavelength division multiple access (WDMA)/optical code division multiplexing (OCDM) system is proposed, where the optical code is not the same as the address of every optical network unit (ONU); rather... A hybrid wavelength division multiple access (WDMA)/optical code division multiplexing (OCDM) system is proposed, where the optical code is not the same as the address of every optical network unit (ONU); rather, the code is a virtual fiber of hybrid passive optical network (PON). To our knowledge, this is the first report analyzing a single encoder/decoder with a single corresponding optical code being exploited to encode/decode multiple wavelength signals simultaneously. This system enables OCDM to become transparent to ONU so that the existing wavelength division multiplexing (WDM) PON can be upgraded. Thus, redesigning the optical line terminal and ONU can be easily accomplished, and greatly decreasing the number of encoder/decoder becomes possible. In experiment, we only employ two encoder/decoder pairs to combine two WDM-PONs in one fiber. Simulation results confirm the feasibility of the proposed system. 展开更多
关键词 Code division multiple access encoding (symbols) Fiber optic networks Multiplexing equipment optical communication Wavelength division multiplexing
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ANALYSIS OF SPECTRAL PHASE ENCODING OCDMA SYSTEM WITH PSEUDORANDOM CODING 被引量:2
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作者 张海滨 宋文涛 +1 位作者 黄培中 李荣玉 《Journal of Shanghai Jiaotong university(Science)》 EI 2002年第1期1-3,共3页
Multiple access interference (MAI) is the most serious interference in spectral phase encoding optical code division multiple access (SPE OCDMA) systems. This paper focuses on the behavior of MAI in SPE OCDMA systems ... Multiple access interference (MAI) is the most serious interference in spectral phase encoding optical code division multiple access (SPE OCDMA) systems. This paper focuses on the behavior of MAI in SPE OCDMA systems with pseudorandom coding. The statistical expectation of multi access interference (MAI) is derived and plotted. The results confirm that MAI can be suppressed effectively by pseudorandom coding with m sequences. 展开更多
关键词 optical CODE-DIVISION MULTIPLE-ACCESS (OCDMA) SPECTRAL phase encoding M-SEQUENCES MULTIPLE-ACCESS inteference (MAI)
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Optoelectronic reservoir computing based on complex-value encoding 被引量:2
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作者 Chunxu Ding Rongjun Shao +5 位作者 Jingwei Li Yuan Qu Linxian Liu Qiaozhi He Xunbin Wei Jiamiao Yang 《Advanced Photonics Nexus》 2024年第6期47-54,共8页
Optical reservoir computing(ORC)offers advantages,such as high computational speed,low power consumption,and high training speed,so it has become a competitive candidate for time series analysis in recent years.The cu... Optical reservoir computing(ORC)offers advantages,such as high computational speed,low power consumption,and high training speed,so it has become a competitive candidate for time series analysis in recent years.The current ORC employs single-dimensional encoding for computation,which limits input resolution and introduces extraneous information due to interactions between optical dimensions during propagation,thus constraining performance.Here,we propose complex-value encoding-based optoelectronic reservoir computing(CE-ORC),in which the amplitude and phase of the input optical field are both modulated to improve the input resolution and prevent the influence of extraneous information on computation.In addition,scale factors in the amplitude encoding can fine-tune the optical reservoir dynamics for better performance.We built a CE-ORC processing unit with an iteration rate of up to∼1.2 kHz using high-speed communication interfaces and field programmable gate arrays(FPGAs)and demonstrated the excellent performance of CE-ORC in two time series prediction tasks.In comparison with the conventional ORC for the Mackey–Glass task,CE-ORC showed a decrease in normalized mean square error by∼75%.Furthermore,we applied this method in a weather time series analysis and effectively predicted the temperature and humidity within a range of 24 h. 展开更多
关键词 optical reservoir computing complex-value encoding time series analysis weather forecast
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星载准绝对式光电编码器抗污方法
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作者 韩庆阳 沈宏海 +2 位作者 马天翔 梁超 王志冲 《北京航空航天大学学报》 北大核心 2025年第6期2014-2021,共8页
为提高星载准绝对式光电编码器的抗油污能力,提出多参考点绝对角位移识别和多读数头数据融合方法。介绍星载准绝对式光电编码器的组成和处理电路设计;提出多参考点绝对角位移的识别方法,防止因油污造成的绝对角位移误识别,并采用多读数... 为提高星载准绝对式光电编码器的抗油污能力,提出多参考点绝对角位移识别和多读数头数据融合方法。介绍星载准绝对式光电编码器的组成和处理电路设计;提出多参考点绝对角位移的识别方法,防止因油污造成的绝对角位移误识别,并采用多读数头数据融合的方法,判断并消除错误的读数头测量数据;通过角位移曲线和角速度曲线对比实验,验证所提方法的有效性,并使用自准直平行光管和23面体检测精度。实验结果表明:所提方法能够有效的解决圆光栅被污染带引起的角位移错误问题,确保角位移正确可靠;经检验角位移误差最大值为4.6",最小值为-0.6",峰峰值为5.2",均方差为4.3"。满足星载准绝对式光电编码器抗污能力和精度要求,并已成功在工程中应用,效果良好。所提方法对提高星载准绝对式光电编码器抗油污能力,有实用价值。 展开更多
关键词 星载 准绝对式光电编码器 抗污能力 多参考点 多读书头
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光电编码器在伺服电机中的故障研究 被引量:1
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作者 王艳 赵志刚 《微特电机》 2025年第6期77-80,共4页
绝对式光电编码器广泛应用于伺服、机器人等高精度控制领域。随着器件国产化率要求的增加,产品的故障概率也随之增加,该故障影响系统的可靠性。对交流伺服电机使用过程中,国产绝对式光电编码器常见故障进行总结与分析,提出电机故障的快... 绝对式光电编码器广泛应用于伺服、机器人等高精度控制领域。随着器件国产化率要求的增加,产品的故障概率也随之增加,该故障影响系统的可靠性。对交流伺服电机使用过程中,国产绝对式光电编码器常见故障进行总结与分析,提出电机故障的快速定位和解决方法。该方法为国产编码器设计改进积累了经验。 展开更多
关键词 光电编码器 伺服电机 故障
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基于多阶门控聚合网络的光学化学结构识别 被引量:1
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作者 林帆 李建华 《计算机工程》 北大核心 2025年第8期364-372,共9页
在光学化学结构识别(OCSR)领域,现有基于深度学习的模型通常依赖于卷积神经网络(CNN)或视觉Transformer进行视觉特征提取,并采用Transformer进行序列解码。这些模型虽然有效,但仍受限于图像特征提取能力和解码时位置编码的精确性,从而... 在光学化学结构识别(OCSR)领域,现有基于深度学习的模型通常依赖于卷积神经网络(CNN)或视觉Transformer进行视觉特征提取,并采用Transformer进行序列解码。这些模型虽然有效,但仍受限于图像特征提取能力和解码时位置编码的精确性,从而影响识别效率。针对这些限制,将多阶门控聚合网络(MogaNet)和引入相对位置编码的Transformer构成的编码解码架构用于OCSR领域,提出一种基于多阶门控聚合网络的光学化学结构识别模型。该模型首先在图像特征提取时通过MogaNet空间聚合模块,捕获多尺度特征并减少特征冗余,并且通过MogaNet通道聚合模块改善通道维度的多样性;其次在序列解码时采用引入相对位置编码的Transformer作为解码器,精准捕捉序列单词之间的相对位置关系。为了训练和验证该模型,构建一个包含40万个分子的化学结构数据集,其中包含Markush结构与非Markush结构。实验结果表明,该模型的准确率达到了92.36%,优于其他现有的模型。 展开更多
关键词 光学化学结构识别 编码解码架构 深度学习 SMILES表达式 多阶门控聚合网络
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Physical twinning for joint encoding-decoding optimization in computational optics:a review 被引量:2
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作者 Liheng Bian Xinrui Zhan +3 位作者 Rong Yan Xuyang Chang Hua Huang Jun Zhang 《Light: Science & Applications》 2025年第6期1484-1503,共20页
Computational optics introduces computation into optics and consequently helps overcome traditional optical limitations such as low sensing dimension,low light throughput,low resolution,and so on.The combination of op... Computational optics introduces computation into optics and consequently helps overcome traditional optical limitations such as low sensing dimension,low light throughput,low resolution,and so on.The combination of optical encoding and computational decoding offers enhanced imaging and sensing capabilities with diverse applications in biomedicine,astronomy,agriculture,etc.With the great advance of artificial intelligence in the last decade,deep learning has further boosted computational optics with higher precision and efficiency.Recently,there developed an end-to-end joint optimization technique that digitally twins optical encoding to neural network layers,and then facilitates simultaneous optimization with the decoding process.This framework offers effective performance enhancement over conventional techniques.However,the reverse physical twinning from optimized encoding parameters to practical modulation elements faces a serious challenge,due to the discrepant gap in such as bit depth,numerical range,and stability.In this regard,this review explores various optical modulation elements across spatial,phase,and spectral dimensions in the digital twin model for joint encoding-decoding optimization.Our analysis offers constructive guidance for finding the most appropriate modulation element in diverse imaging and sensing tasks concerning various requirements of precision,speed,and robustness.The review may help tackle the above twinning challenge and pave the way for next-generation computational optics. 展开更多
关键词 computational optics optical encoding physical twinning joint encoding decoding optimization artificial intelligence deep learning computational decoding
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强化音符位置及方向先验信息的多音光学乐谱识别
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作者 关欣 刘津津 +1 位作者 刘辉 李锵 《天津大学学报(自然科学与工程技术版)》 EI CAS 北大核心 2025年第1期101-110,共10页
由于同一个时刻包含多个音符的多音乐谱其音符符头距离近、符号间依赖关系复杂,使得多音光学乐谱识别极具挑战.传统基于卷积和序列建模的方法,由于经典卷积存在移不变性难以精确表示音符的纵向位置信息,而传统针对上下文序列建模的方法... 由于同一个时刻包含多个音符的多音乐谱其音符符头距离近、符号间依赖关系复杂,使得多音光学乐谱识别极具挑战.传统基于卷积和序列建模的方法,由于经典卷积存在移不变性难以精确表示音符的纵向位置信息,而传统针对上下文序列建模的方法难以有效表征调号中变音记号与五线谱内符头的空间相关性,存在符头音高识别不准、变音记号作用范围有限的问题,从而影响音符音高、时值标注的准确性.针对以上问题,提出了一种强化音符位置及方向先验信息的多音光学乐谱识别方法.首先,提出一种纵向位置编码方法,将纵向位置信息嵌入乐谱图像,以更精确地表示符头的纵向位置信息,从而能明确区分多音乐谱中的不同音高.其次,提出了变音记号位置注意力,以明确建立变音记号和符头的空间依赖关系.最后,针对多音符头纵向分布、音符序列横向排列、音符符头、符干和符尾呈现的局部方向性特点,提出了方向注意力模块,更好地捕捉音符特征分布的方向性.在多音乐谱数据集上开展实验,实验结果表明,该方法对时值识别的符号错误率为1.14%,对音高识别的符号错误率为2.14%.与当前基准方法卷积递归神经网络相比,该方法时值识别的符号错误率降低了0.67%,对音高识别的符号错误率降低了1.14%,对多音乐谱具有良好的识别效果. 展开更多
关键词 光学乐谱识别 位置编码 位置注意力 方向注意力
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基于嵌入式技术的光通信信号智能处理系统 被引量:3
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作者 张萌 谷栎娜 +1 位作者 薛少童 张通 《激光杂志》 北大核心 2025年第2期168-173,共6页
为实现信号快速传输,提高光通信系统稳定性,设计基于嵌入式技术的光通信信号智能处理系统。构建光通信信号智能处理系统框架,将采DSP处理模块嵌入到光通信系统中,以LED阵列作为光源,获得光通信原始信号,在DSP中完成RS编码、截断的PPM调... 为实现信号快速传输,提高光通信系统稳定性,设计基于嵌入式技术的光通信信号智能处理系统。构建光通信信号智能处理系统框架,将采DSP处理模块嵌入到光通信系统中,以LED阵列作为光源,获得光通信原始信号,在DSP中完成RS编码、截断的PPM调制,将其作用到LED上实现光通信信号的发送,经过信道传输后,通过凸透镜聚集传送光束并由探测器阵列接收光信号,采用Berlekamp-Massey算法完成信号解译,利用由高带宽增益积运算放大器、全差分运算放电器、限幅放大器构成两极信号处理电路完成原始输入信号的复原。实验结果表明:该系统可保证5 km通信距离下光通信信号的稳定传输,随着通信距离的增长,误码率呈小幅度变大,2.5 km通信距离内,误码率为0,可实现输入信号的准确恢复,收发端信噪比不低于74 dB,信号处理性能突出。 展开更多
关键词 嵌入式技术 光通信 DSP LED阵列 RS编码 PPM调制
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