模拟电路软故障诊断的研究

分析了模拟电路软故障诊断的重要性及现有的各种软故障诊断方法。对模拟电路软故障诊断字典法中基于支路屏蔽原理、电路参数随元件参数变化轨迹、节点电压灵敏度序列守恒定理和节点电压增量关系方程的四个研究方向各自的基本原理和优缺点进行了探讨;介绍了基于神经网络,结合模糊理论、小波变换的现代模拟电路软故障诊断的两个方向的研究现状;同时从通用的软故障诊断方法、大规模模拟电路的诊断策略和数模混合集成电路的诊断需求三方面指出了模拟电路软故障诊断的发展趋势和亟待解决的问题。     

AC/DC开关电源建模与仿真研究

文章对全桥型开关电源结构进行分析,对关键元器件的作用、参数计算方法进行阐述.在Multisim仿真软件中搭建整体电路模型,研究改变电路参数对于电路性能的影响,验证开关电源仿真的可行性.针对硬开关产生的开关损耗问题,建立ZVS-移相全桥变换器的简化模型,仿真研究开关管的软开关过程.     

A Liquid Metal Based Multimodal Sensor and Haptic Feedback Device for Thermal and Tactile Sensation Generation in Virtual Reality

Virtual reality (VR) has been widely used for training, gaming, and entertainment, and the value of VR is continually increasing as a contact-free technology. For an immersive VR experience, measuring finger movements and providing appropriate feedback to the hand are as important as visual information, given the necessity of the hands for activities in daily life. Thus, a hand-worn VR device with motion sensors and haptic feedback is desirable. In this paper, a multimodal sensing and feedback glove is developed with soft, stretchable, lightweight, and compact sensor and heater sheets manufactured by direct ink writing (DIW) of liquid metal, eutectic gallium-indium (eGaIn). In the sensor sheet, ten sensors and three vibrators are embedded to measure finger movements and provide vibro-haptic feedback. The other heater sheet provides thermo-haptic sensation in accurate and rapid manner via model-based feedback control even under stretched conditions. The multimodal sensing and feedback glove allows users to feel the contact status and discriminate materials with different temperature. Performance of the proposed multimodal glove is verified under VR environments including touching and pushing two blocks of different materials and grabbing a heated metal ball submerged in hot water.     

Attribute Allocation and Retrieval Scheme for Large-Scale Sensor Networks

Wireless sensor network is an emerging technology that enables remote monitoring of large geographical regions. In this paper, we address the problem of distributing attributes over such a large-scale sensor network so that the cost of data retrieval is minimized. The proposed scheme is a data-centric storage scheme where the attributes are distributed over the network depending on the correlations between them. The problem addressed here is similar to the Allocation Problem of distributed databases. In this paper, we have defined the Allocation Problem in the context of sensor networks and have proposed a scheme for finding a good distribution of attributes to the sensor network. We also propose an architecture for query processing given such a distribution of attributes. We analytically determine the conditions under which the proposed architecture is beneficial and present simulation results to demonstrate the same. To the best of our knowledge, this is the first attempt to determine an allocation of attributes over a sensor network based on the correlations between attributes.     

用于ICF实验的轴对称掠入射软X射线显微镜中的光学系统

简单叙述了几种可用于ICF实验研究的掠入射软X射线显微镜的主镜结构 ,详细介绍了WolterⅠ型轴对称掠入射软X射线显微镜的成像原理、系统的主镜参数以及系统中用到的观察瞄准系统的光学方案。     

半导体物理实验教学探索与实践

"半导体物理学"是电子信息类专业重要的专业基础课,其教学效果将影响微电子创新人才的培养质量。我们针对目前部分高校存在实验条件不足、半导体物理实践教学环节缺失的情况,提出了用半导体材料和器件模拟平台搭建虚拟半导体实验室,以弥补传统的半导体基础实验室开展实践教学的不足。教学实践证明,这一方式有效地调动了学生对本课程的学习积极性,教学效果得到了明显改善。     

基于OPNET的UMTS切换技术的建模与仿真

切换技术是通用移动通信系统(Universal Mobile Telecommunications System,UMTS)的主要关键技术之一,用于保证用户在移动通信网络中的移动性。对目前主要使用的2种切换技术———软切换和硬切换进行了简要介绍,而软切换是码分多址(Code Division Multiple Access,CDMA)系统所特有的。利用OPNET仿真软件搭建了UMTS网络切换模型,对软切换及硬切换技术进行仿真,并对结果进行了比较分析,得出结论,切换技术的优劣会直接影响到系统提供的服务质量。     

3D Knitting for Pneumatic Soft Robotics

Soft robots adapt passively to complex environments due to their inherent compliance, allowing them to interact safely with fragile or irregular objects and traverse uneven terrain. The vast tunability and ubiquity of textiles has enabled new soft robotic capabilities, especially in the field of wearable robots, but existing textile processing techniques (e.g., cut-and-sew, thermal bonding) are limited in terms of rapid, additive, accessible, and waste-free manufacturing. While 3D knitting has the potential to address these limitations, an incomplete understanding of the impact of structure and material on knit-scale mechanical properties and macro-scale device performance has precluded the widespread adoption of knitted robots. In this work, the roles of knit structure and yarn material properties on textile mechanics spanning three regimes–unfolding, geometric rearrangement, and yarn stretching–are elucidated and shown to be tailorable across unique knit architectures and yarn materials. Based on this understanding, 3D knit soft actuators for extension, contraction, and bending are constructed. Combining these actuation primitives enables the monolithic fabrication of entire soft grippers and robots in a single-step additive manufacturing procedure suitable for a variety of applications. This approach represents a first step in seamlessly “printing” conformal, low-cost, customizable textile-based soft robots on-demand.     

超薄栅氧化层中的软击穿的击穿机理和击穿模型

软击穿是与氧化层质量密切相关的一种新的击穿形式。当氧化层厚度小于5nm时,软击穿效应显著,是超薄栅氧化层的主要失效机理。通过对国外软击穿研究状况的分析,对超薄栅氧化层中软击穿的失效模型和机理进行了综述。     

高密度封装技术推动测试技术发展

高密度封装技术的飞速发展也给测试技术提出了新挑战。为了应对挑战,新的测试技术不断涌现。本文主要介绍了几种新型测试技术的特点,并对未来测试技术的发展趋势及方向进行了初步分析。