Four-junction AlGaAs/GaAs laser power converter

Four-junction A1GaAs/GaAs laser power converters (LPCs) with n+-GaAs/p+-Al0.37Ga0.63As heterostructure tunnel junctions (TJs) have been designed and grown by metal-organic chemical vapor deposition (MOCVD) for converting the power of 808 nm lasers.A maximum conversion efficiency ηc of 56.9％ + 4％ is obtained for cells with an aperture of 3.14 mm2 at an input laser power of 0.2 W,while dropping to 43.3％ at 1.5 W.Measured current-voltage (I-V) characteristics indicate that the performance of the LPC can be further improved by increasing the tunneling current density of TJs and optimizing the thicknesses of sub-cells to achieve current matching in LPC.     

基于大数据和AI的智能化PeOTN-CO价值分级建网创新与实践

对某省联通PeOTN-CO价值分级建网方法论及实践进行了论述,通过市场空间大数据分析、AI算法及存量政企专线路径和流量等分析,对全省综合业务接入区(CO)进行价值分级,提出聚类标杆配置模型,优先预覆盖高价值综合业务接入点,次优先覆盖中低价值区域,实现政企精品网的价值精准建网,进而全面实现以PeOTN技术为主的本地光网络边缘延伸,打造智能光网络,适配新基建时代的“大带宽”“低时延”等业务需求特征,有效降低网络成本并提高短期投资回报率。     

基于SIFT特征点结合ICP的点云配准方法

在点云配准过程中,针对迭代最近点(ICP)算法对点云初始位置依赖性强且迭代速度慢的问题,提出一种基于尺度不变特征变换(SIFT)特征点结合ICP的点云配准方法.首先利用SIFT算法提取待配准点云和目标点云的特征点;接着计算出特征点的快速点特征直方图(FPFH)特征;然后依据该特征使用采样一致性初始配准(SAC-IA)算...     

Recent Progress in Solar‐Blind Deep‐Ultraviolet Photodetectors Based on Inorganic Ultrawide Bandgap Semiconductors

Due to its significant applications in many relevant fields, light detection in the solar‐blind deep‐ultraviolet (DUV) wavelength region is a subject of great interest for both scientific and industrial communities. The rapid advances in preparing high‐quality ultrawide‐bandgap (UWBG) semiconductors have enabled the realization of various high‐performance DUV photodetectors (DUVPDs) with different geometries, which provide an avenue for circumventing numerous disadvantages in traditional DUV detectors. This article presents a comprehensive review of the applications of inorganic UWBG semiconductors for solar‐blind DUV light detection in the past several decades. Different kinds of DUVPDs, which are based on varied UWBG semiconductors including Ga₂O₃, Mg_xZn_1?xO, III‐nitride compounds (Al_xGa_1?xN/AlN and BN), diamond, etc., and operate on different working principles, are introduced and discussed systematically. Some emerging techniques to optimize device performance are addressed as well. Finally, the existing techniques are summarized and future challenges are proposed in order to shed light on development in this critical research field.     

Distinctive Performance of Terahertz Photodetection Driven by Charge‐Density‐Wave Order in CVD‐Grown Tantalum Diselenide

The quantum behavior of carriers in solid is the foundation of modern electronic and optoelectronic technology, but it is still facing huge challenges within inherited single‐particle quantum processes working at the millimeter wave/terahertz (THz) band. Here, a straightforward strategy for the direct detection of millimeter wave/THz photons in a sub‐wavelength metal‐TaSe₂‐metal structure under strong interaction with a localized field of surface plasmon is proposed. By breaking the inversion symmetry under the perturbations of electric field and atomic reconstruction from van der Waals integration, the nonequilibrium electronic states under a radiant field can be manipulated in a collective fashion, leading to a large photocurrent responsivity over 40 A W^?1 and noise equivalent power less than 1 pW Hz^?1/2 even at room temperature. A more than 40‐fold enhancement in responsivity is achieved when transitioning from the normal phase to the CDW phase. The findings shed fresh light on the understanding of the delicate balance in the charge‐ordered phase, and facilitate the exploitation of a correlated electron system for optoelectronic applications in fields of security, remote sensing, and imaging.     

机电伺服系统的组合式能源技术研究

针对当前伺服能源论证需求分析,结合机电伺服系统长时小功率、瞬时高功率、制动负功率的用电特性,提出采用基于能量管理的组合式伺服能源方法,提高了伺服系统的能量利用率;通过试验验证,该方法既满足用电要求,又保证了伺服电源高可靠性、轻小型化的设计,为伺服能源设计提出新思路、新方法。     

红外增强器与干扰弹

介绍了红外增强器和干扰弹的辐射特性, 及其在光电对抗系统中的作用, 给出两类光谱辐射特性曲线、光谱辐射数据、红外热辐射特征、时域变化特性曲线等, 介绍了选用的基本原则并提出使用时应注意的事项。     

对某自动机双路供弹机的分析

以某双路供弹机为研究对象，分析了火药燃气驱动、弹链供弹、横向移动式双路供弹机的工作原理和结构特点，通过对计算结果的分析得出，扭簧是供弹机构中不可缺少的构件，并对供弹方式提出了改进建议。     

无人战斗机综合控制系统自动机动轰炸仿真研究

通过对无人战斗机进行综合火力/飞行控制系统设计,对无人战斗机在自动机动攻击方式下进行了仿真.从仿真结果可以看出,所提出的综合方案是适用、可行、有效的.把火力飞行综合控制系统应用到无人战斗机,提高了无人机的攻击精度,减少了遥控指挥人员的干预.     

Image Restoration Using Hybrid Features Improvement on Morphological Component Analysis

Images are generally corrupted by impulse noise during acquisition and transmission. Noise deteriorates the quality of images. To remove corruption noise, we propose a hybrid approach to restoring a random noise-corrupted image, including a block matching 3D (BM3D) method, an adaptive non-local mean (ANLM) scheme, and the K-singular value decomposition (K-SVD) algorithm. In the proposed method, we employ the morphological component analysis (MCA) to decompose an image into the texture, structure, and edge parts. Then, the BM3D method, ANLM scheme, and K-SVD algorithm are utilized to eliminate noise in the texture, structure, and edge parts of the image, respectively. Experimental results show that the proposed approach can effectively remove interference random noise in different parts; meanwhile, the deteriorated image is able to be reconstructed well.