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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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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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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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基于脉冲神经网络的区段煤柱变形预测
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作者 杨健锋 景超 +5 位作者 柴敬 张丁丁 刘泽宇 杨磊 雒可 赵鹏翔 《西安科技大学学报》 北大核心 2025年第6期1121-1131,共11页
在近距离煤层开采过程中,遗留煤柱下区段煤柱的变形影响巷道的稳定性。以大柳塔矿活鸡兔井22208工作面回采巷道为工程背景,采用分布式光纤传感技术对区段煤柱内部的水平变形进行表征。在此基础上,提出一种改进的自适应脉冲编码方法,将... 在近距离煤层开采过程中,遗留煤柱下区段煤柱的变形影响巷道的稳定性。以大柳塔矿活鸡兔井22208工作面回采巷道为工程背景,采用分布式光纤传感技术对区段煤柱内部的水平变形进行表征。在此基础上,提出一种改进的自适应脉冲编码方法,将采集的应变数据转换为脉冲信号,作为脉冲神经网络(SNN)预测模型的输入。采用泄漏积分发放(LIF)神经元模型构建脉冲神经网络,并引入奖励调节的突触可塑性(R-STDP)学习机制进行训练和测试。结果表明:分布式光纤传感技术能够有效反映区段煤柱内部变形的真实状态;相较于传统神经网络模型,改进自适应脉冲编码的SNN模型在煤柱变形预测方面表现更优,其预测结果的均方根误差降低了0.81,平均绝对百分比误差减少了27%。研究为近距离煤层开采过程中的巷道稳定性评估与安全控制提供了重要的技术依据。 展开更多
关键词 分布式光纤传感 煤柱内部变形 自适应编码 脉冲神经网络
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变转速工况下瞬时角速度精确估计及其在轴承故障检测中应用
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作者 唐安林 陈鑫 +3 位作者 郭瑜 李超 田书锦 隆勇 《振动与冲击》 北大核心 2025年第22期255-263,314,共10页
为实现变转速工况下瞬时角速度(instantaneous angular speed,IAS)的精确估计,以双光编码器为信号源,研究提出了一种双光编码器同步时间差的IAS信号高精度估计方法。首先,针对编码器信号上升沿/下降沿相位与高速计数器非同步性IAS的量... 为实现变转速工况下瞬时角速度(instantaneous angular speed,IAS)的精确估计,以双光编码器为信号源,研究提出了一种双光编码器同步时间差的IAS信号高精度估计方法。首先,针对编码器信号上升沿/下降沿相位与高速计数器非同步性IAS的量化误差,研究提出了过零时间法补偿量化误差方案;其次,开展了变转速工况下IAS信号波动特性研究,归纳了速度趋势分量对滚动轴承故障检测的难点;最后,研究提出一种循环互相关的双编码器时间序列同步方法,实现了变转速工况下IAS信号的动态精确估计。通过试验信号验证所提方法在滚动轴承故障检测中的有效性,并与传统速度差分法进行对比分析。 展开更多
关键词 瞬时角速度 双编码器 变转速 滚动轴承 同步时间差分
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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:2
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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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Optical information transfer through random unknown diffusers using electronic encoding and diffractive decoding 被引量:6
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作者 Yuhang Li Tianyi Gan +3 位作者 Bijie Bai Cagatay Isıl Mona Jarrahi Aydogan Ozcan 《Advanced Photonics》 SCIE EI CAS CSCD 2023年第4期85-99,共15页
Free-space optical information transfer through diffusive media is critical in many applications, such as biomedical devices and optical communication, but remains challenging due to random, unknown perturbations in t... Free-space optical information transfer through diffusive media is critical in many applications, such as biomedical devices and optical communication, but remains challenging due to random, unknown perturbations in the optical path. We demonstrate an optical diffractive decoder with electronic encoding to accurately transfer the optical information of interest, corresponding to, e.g., any arbitrary input object or message, through unknown random phase diffusers along the optical path. This hybrid electronic-optical model, trained using supervised learning, comprises a convolutional neural network-based electronic encoder and successive passive diffractive layers that are jointly optimized. After their joint training using deep learning,our hybrid model can transfer optical information through unknown phase diffusers, demonstrating generalization to new random diffusers never seen before. The resulting electronic-encoder and optical-decoder model was experimentally validated using a 3D-printed diffractive network that axially spans <70λ, whereλ = 0.75 mm is the illumination wavelength in the terahertz spectrum, carrying the desired optical information through random unknown diffusers. The presented framework can be physically scaled to operate at different parts of the electromagnetic spectrum, without retraining its components, and would offer low-power and compact solutions for optical information transfer in free space through unknown random diffusive media. 展开更多
关键词 optical information transfer electronic encoding optical decoder diffractive neural network DIFFUSERS
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