Author Affiliations
Abstract
1 Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China
2 e-mail: hailongzhou@hust.edu.cn
Optical computing has shown immense application prospects in the post-Moore era. However, as a crucial component of logic computing, the digital multiplier can only be realized on a small scale in optics, restrained by the limited functionalities and inevitable loss of optical nonlinearity. In this paper, we propose a time-space multiplexed architecture to realize large-scale photonic-electronic digital multiplication. We experimentally demonstrate an -bit photonic-electronic digital multiplier, and the multiplication with a 32-bit number is further executed at 25 Mbit/s to demonstrate its extensibility and functionality. Moreover, the proposed architecture has the potential for on-chip implementation, and a feasible integration scheme is provided. We believe the time-space multiplexed photonic-electronic digital multiplier will open up a promising avenue for large-scale photonic digital computing.
Photonics Research
2024, 12(3): 499
Author Affiliations
Abstract
1 Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China
2 Optics Valley Laboratory, Wuhan 430074, China
With the advancement of deep learning and neural networks, the computational demands for applications in wearable devices have grown exponentially. However, wearable devices also have strict requirements for long battery life, low power consumption, and compact size. In this work, we propose a scalable optoelectronic computing system based on an integrated optical convolution acceleration core. This system enables high-precision computation at the speed of light, achieving 7-bit accuracy while maintaining extremely low power consumption. It also demonstrates peak throughput of 3.2 TOPS (tera operations per second) in parallel processing. We have successfully demonstrated image convolution and the typical application of an interactive first-person perspective gesture recognition application based on depth information. The system achieves a comparable recognition accuracy to traditional electronic computation in all blind tests.
optoelectronic compute wearable devices micro-ring resonator hand gesture recognition Opto-Electronic Science
2023, 2(12): 230017
1 东华理工大学 土木与建筑工程学院, 南昌 330013
2 广西大学 土木建筑工程学院, 南宁 530000
3 三明莆炎高速公路有限责任公司, 三明 365000
为了研究隧道围岩在静动应力耦合作用下的变形和损伤情况, 建立地应力与爆破荷载耦合作用的隧道模型。首先依据文笔山隧道现场监测数据和岩体波速反推围岩的JH2本构参数。根据围岩等级, 结合已知参数和波动方程, 给出简易的JH2本构参数确定方法, 并通过子程序嵌入ABAQUS中建立围岩的损伤模型; 为了使仿真模型更接近现实情况, 先进行地应力平衡, 将此时的土体状态作为爆破模拟的初始应力状态, 再采用等效爆破荷载法模拟隧道爆破, 以此在宏观上实现大型岩土工程在静动应力耦合作用下的爆破仿真。仿真模型不仅考虑爆破面的爆破效果, 还着重研究爆破对隧道围岩的影响情况。研究结果表明: 初始地应力在隧道爆破中对围岩的损伤和变形都有不可忽视的作用。初始地应力的存在诱导损伤扩展, 地应力越大, 损伤越大, 拱底在竖向发生2.2 m最大损伤深度; 在相同进尺, 地应力越小变形越大, 拱顶在靠近开挖面处产生11.7 mm最大变形。围岩上下的水平收敛变形不同: 上部背离隧道, 下部指向隧道, 围岩上下台阶分界处受剪切荷载。围岩的损伤与变形贴合实际工程, 研究结果丰富隧道爆破模拟, 对隧道爆破施工有现实指导意义。
隧道 Johnson-Holmquist-Ⅱ模型 动静应力耦合 等效爆破 数值仿真 tunnel Johnson-Holmquist-Ⅱ material model dynamic and static stress coupling equivalent blasting numerical simulation
Author Affiliations
Abstract
1 Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China
2 The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, 518057, China
3 Photonics Research Institute, Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong 999077, China
4 Department of Physics, Hong Kong Baptist University, Kowloon Tong, 999077 Hong Kong, China
The increasing amount of data exchange requires higher-capacity optical communication links. Mode division multiplexing (MDM) is considered as a promising technology to support the higher data throughput. In an MDM system, the mode generator and sorter are the backbone. However, most of the current schemes lack the programmability and universality, which makes the MDM link susceptible to the mode crosstalk and environmental disturbances. In this paper, we propose an intelligent multimode optical communication link using universal mode processing (generation and sorting) chips. The mode processor consists of a programmable 4 × 4 Mach Zehnder interferometer (MZI) network and can be intelligently configured to generate or sort both quasi linearly polarized (LP) modes and orbital angular momentum (OAM) modes in any desired routing state. We experimentally establish a chip-to-chip MDM communication system. The mode basis can be freely switched between four LP modes and four OAM modes. We also demonstrate the multimode optical communication capability at a data rate of 25 Gbit/s. The proposed scheme shows significant advantages in terms of universality, intelligence, programmability and resistance to mode crosstalk, environmental disturbances, and fabrication errors, demonstrating that the MZI-based reconfigurable mode processor chip has great potential in long-distance chip-to-chip multimode optical communication systems.
1 上海大学力学与工程科学学院, 上海 200444
2 上海市城市建设设计研究总院(集团)有限公司, 上海 200125
为探究砂浆-混凝土接缝界面动态受压力学性能, 设计混凝土、砂浆以及砂浆-混凝土接缝界面三种不同试件, 应用液压伺服试验机和霍普金森杆(SHPB)对试件静动态力学性能展开试验研究, 由试验获取不同拼接缝工况下试件破坏形态和力学特征参数。同时, 利用CT扫描技术, 分析了三种不同试样的动态增强效果, 并从细观层面揭示了其作用机理。结果表明: 在静态作用下, 接缝试件整体抗压强度处于砂浆试件与混凝土试件之间; 在动态作用下, 三种不同试件抗压强度随着应变率提高逐步增加, 混凝土对应变率有更强的敏感性, 砂浆的敏感性最弱。相较于混凝土试件, 砂浆和砂浆-混凝土接缝试件受压破坏后的完整性显著提升; 利用试验数据并基于欧洲混凝土委员会提出的CEB公式优化得到适用于三种不同材料的动态提高因子(DIF)与应变率数学模型, 该模型具有较好的适用性。
砂浆-混凝土接缝 动态力学性能 应变率效应 动态提高因子 mortar-concrete joint dynamic mechanical property strain rate effect dynamic increase factor
1 中国科学院大学集成电路学院,北京 100049
2 中国科学院上海高等研究院,上海 201210
3 上海信息技术研究中心,上海 201210
同步辐射光源产生超高速的衍射图像数据流,需要通过数据筛选降低数据传输和存储的压力。但互相竞争的研究小组不愿意分享数据,现有基于深度学习的筛选方法难以应对隐私保护下有效训练的挑战,因此首次将联邦学习技术应用在辐射光源衍射图像筛选中,通过数据和模型分离,实现隐私保护下的训练数据增广。提出筛选方法Federated Kullback-Leibler(FedKL),基于改进的KL散度和数据量权重,对全局模型更新进行改进,在获得高准确率的同时降低算法的复杂度,满足高速数据流高精度处理要求。针对异地光源多中心数据同步训练的困难,又提出同步和异步相结合的混合训练方式,在不降低模型识别准确率的同时,显著提升了模型的训练速度。在光源CXIDB-76公开数据集上的实验结果表明,相比FedAvg,FedKL能够提升准确率和F1分数,分别提升了25.2个百分点和0.419。
隐私保护 图像筛选 联邦学习 布拉格斑点 相对熵 激光与光电子学进展
2023, 60(10): 1010020
1 首都医科大学生物医学工程学院,北京 100069
2 首都医科大学临床生物力学应用基础研究北京市重点实验室,北京 100069
3 首都医科大学宣武医院骨科,北京 100053
在手术导航系统辅助的椎弓根螺钉内固定术中,术前与术中点云配准精度是影响导航定位效果的重要因素。由于术前与术中点云的获取方式不同,且术中暴露位置受限,两种非同源三维点云存在初始位姿差异大、重叠率低的问题,现有的配准算法在术前术中点云配准时容易失效且精度不高。为此,本文提出了一种椎弓根螺钉内固定术中非同源低重叠率点云的配准方法。首先,对术中点云进行降采样,对术前点云进行基于最远点采样的局部区域划分,选取其中的最优局部区域,与术中点云进行采样一致性初始配准;之后,采用迭代最近点算法进行进一步优化,实现点云的准确对齐。在本文所用数据集上,所提算法在术前术中点云配准实验中的平均旋转误差为0.406°,平移误差为0.474 mm,实现了初始位姿差异大、重叠率低的非同源术前术中点云的高精度配准,与现有算法相比,配准成功率从66.67%提高至100%。
医用光学 椎弓根螺钉内固定术 非同源点云 初始位姿差异大 低重叠率 点云配准
1 成都信息工程大学 光电工程学院, 成都 610225
2 电子科技大学 航空航天学院, 成都 610054
为了实现大气湍流动态干扰下望远镜对远距离目标的超衍射极限成像, 采用光学超振荡原理局部衍射压缩光学系统点扩散函数, 并对提高成像分辨率效果进行了理论研究。结果表明, 中等湍流强度校正后,波前残差均方根约为波长的1/15(波长λ=632.8 nm)时的干扰下, 超振荡光场调制能够实现望远系统点扩散函数的衍射压缩, 衍射压缩倍率为0.75; 对不同中心间距双孔的成像研究验证了超振荡望远系统约0.80倍瑞利衍射极限的超分辨成像效果; 波前残差的均方根大小可能会导致望远系统点扩散函数的衍射压缩倍率和成像分辨率存在差异。此研究结果可应用于高精度星点定位、超分辨望远等领域。
傅里叶光学 望远镜 超振荡 大气湍流 Fourier optics telescope super-oscillation atmospheric turbulence