聚氨酯隔振器非线性力学模型与特性研究

结合聚氨酯隔振器和简单形状试样的静态和动态试验结果,建立了由弹簧、阻尼器和摩擦元件等多组机械元件所构成的聚氨酯隔振器非线性广义模型,试验分析了不同激振振幅、激振频率和预加载情况下的隔振器静动态特性,研究了聚氨酯隔振器的弹性、弹塑性和粘弹性特点,分析和验证了它们对隔振器静动态特性的影响。采用非线性广义模型分析法来研究隔振器的力学模型,物理概念清晰,能够比较直观、简洁、全面地描述隔振器的性能特点,可推广应用于其他类型隔振器。     

镁合金中的LPSO结构

详细描述了铁合金中的LPSO相的最新研究进展,系统总结了镁合金中的LPSO相的结构、微合金组元的化学成分,分析了微观形成过程与机制以及优异的力学性能,展望了镁合金中LPSO结构的研究趋势.     

5-(3-羧基苯偶氮)-8-氨基喹啉光度法测定铜

研究了新有机试剂５－（３－羧基苯偶氮）－８－氨基喹淋（ｍ－ＣＰＡＱ）的合成、鉴定及其与铜（Ⅱ）的显色反应。在ｐＨ６．６时,Ｃｕ（Ⅱ）与ｍ－ＣＰＡＱ形成１：３的稳定的紫红色络合物。其最大吸收峰在５５４ｎｍ,摩尔吸光系数ε＝７．３×１０４Ｌ·ｍｏｌ－１·ｃｍ－１,铜量在０～１６μｇ／２５ｍｌ范围内符合比尔定律。方法有高的灵敏度和选择性,用于实际样品分析,结果满意。     

数字录像机的特点及其保养

针对数字录像机的特点,简要介绍数字录像机在实际使用过程中的维护和保养.     

电视节目制作领域中的虚拟演播室系统

虚拟演播室系统应用于电视节目制作领域以后,既提高了节目制作的质量,又降低了节目制作的成本,对电视节目的制作产生了很大的影响.从虚拟演播室系统的基本工作原理、虚拟演播室系统的主要技术等几个方面进行简要论述.     

新型亚波长光栅横向腔面发射激光器

本文报道一种新型的横向腔面发射激光器,基于亚波长光栅平面内的横向谐振与垂直发射。器件采用不含DBR结构的商用波导外延材料,不需要晶片键合技术。在1552.44 nm处获得了23.0 dB的边模抑制比,最高输出功率5.32 mW。此单模激射与带边模式计算相吻合。在3维的模拟中,我们观察到光栅表面的光输出。     

基于元伪标签和光照不变特征的人脸反欺诈算法CSCD

Face anti-spoofing (FAS) plays a vital role in preventing face recognition systems from presentation attacks. Benefitted from powerful capability of feature extraction of deep learning (DL) network, FAS algorithms based on deep learning are much superior to those ones based on traditional handcrafted features in detection performance and thus become a research hotspot. Although most DL-based FAS algorithms can achieve good performance for intra-database test, the performance decreases greatly for cross-database test. The main reason is that samples are often collected under different capturing settings for intra-database and cross-database, for example, different cameras, environment illuminations, presentation medium, and thus their distributions are different, which can lead to the domain shift problem. When the diversity of training samples is insufficient, a model trained with such samples can be easily overfitting for intra-database while not being able to perform well for cross-database. Although the reasons of poor generalization are clear, the solution to them cannot be easily achieved in real-world applications. On the one hand, it is difficult for the FAS model to collect labeled training samples for all scenarios; on the other hand, different application scenarios make the same factor behave differently, which affects the extraction of intrinsic spoofing textures. In this paper, we introduce meta-pseudo-label into the FAS task, and propose a FAS method based on meta-pseudo-label. There are three major contributions. First, we propose a semi-supervised learning framework of “teacher generates pseudo-label and student feedbacks” based on image patches, which extracts the highly discriminative features of local images to solve the problem of insufficient labeled samples. Second, based on the Pattern of Local Gravitational Force (PLGF), we design an illumination-invariant feature branch with an attention module to suppress the illumination influence on feature extraction in application scenarios. Third, the meta-learning is combined with the semi-supervised learning framework to optimize the process of generating pseudo-label by teacher and improve the generalization ability of the algorithm. Compared with state-of-the-art algorithms, the proposed method performs quite well in both intra-database test and cross-database test on three public datasets including CASIA, Replay-Attack, and MSU. Specifically, the performance in cross-database is greatly improved. It can achieve the lowest HTER values for middle-sized sample number. © 2023 Chinese Academy of Sciences. All rights reserved.     

提高包钢带式机生球质量生产实践

造球工序是球团生产中的关键环节,生球质量的好坏将直接影响成品球的产质量.通过提高铁料干燥效果、强化高压辊磨工序以及优化造球机参数等措施,使成球率由75％提高到81％,平均生球落下强度提高0.3次,生球质量得到明显改善.     

篮牙技术的开发及应用探讨

本文简述了蓝牙技术,并对该技术在无线电产品中的应用作了介绍。文中还对该技术在船舶通信系统中的应用潜力做了一些初步探讨。     

江西上犹小寨背高岭土矿矿床地质特征及矿床成因

江西上犹小寨背高岭土矿床成矿原岩为白云母花岗岩和二云母花岗岩,其特征为高硅、富铝,低铁、钛。通过研究该矿床成矿原岩成分特征、矿床地质特征、构造特征、地形地貌及有利的风化作用,阐明其矿床成因及其找矿标志。