毫米波三维异质异构集成技术的进展与应用

三维异质异构集成技术是实现电子信息系统向着微型化、高效能、高整合、低功耗及低成本方向发展的最重要方法,也是决定信息化平台中微电子和微纳系统领域未来发展的一项核心高技术。文章详细介绍了毫米波频段三维异质异构集成技术的优势、近年来的发展趋势以及面临的挑战。利用硅基MEMS 光敏复合薄膜多层布线工艺可实现异质芯片的低损耗互连,同时三维集成高性能封装滤波器、高辐射效率封装天线等无源元件,还能很好地处理布线间的电磁兼容和芯片间的屏蔽问题。最后介绍了一款新型毫米波三维异质异构集成雷达及其在远距离生命体征探测方面的应用。     

基于平均飞行航迹的CCO减噪效用研究

近年来，通过优化飞行程序降低机场飞机噪声影响成为机场环境保护的重要研究方向。文章首先建立了基于飞机“噪声-功率-距离”数据的噪声计算模型，介绍了平均飞行航迹以及连续爬升运行(Continuous Climb Opera-tion, CCO)离场程序的相关理论，最后以大型国际机场为实例，使用飞机平均飞行航迹进行噪声预测，运用综合噪声模型计算出噪声影响面积并绘制噪声影响等值线图，比较了CCO离场相对常规的标准仪表离场(Standard Instru-ment Departure, SID)的降噪效果。结果表明，CCO离场程序可有效降低机场噪声影响，在高噪声级影响区域的降噪效果更佳。     

3D打印裂隙岩体动态力学性能及能量耗散规律初探

地下岩体结构经常遭受到地震、爆炸、冲击振动等产生的动力扰动，利用3D打印技术的优势研究冲击荷载下岩体动态力学性能对实现3D打印技术在工程领域的应用具有重要意义。采用φ50 mm的变截面霍普金森压杆(SHPB)装置，对含预制裂隙的3D打印岩体试样进行动态单轴压缩试验。研究结果表明：试样的动态抗压强度随着预制裂隙倾角的增大呈现出先减小后增大的趋势，当预制裂隙倾角为30°时试样强度最小，当预制裂隙倾角为90°时试样强度最大。与3D打印岩体试样的静态单轴压缩强度对比发现，3D打印砂性材料具有明显的率效应，当应变率为139.65 s^-1时，3D打印岩体试样的动态抗压强度是静态抗压强度的4.34倍。预制裂隙缺陷在一定程度上加剧了试样的能量耗散和破碎过程，并且30°倾角预制裂隙对试样能量耗散和破碎结果的影响程度最大。同时，3D打印岩体试样的能量耗散过程与破碎块度表现出明显的自相关性，所用的3D打印砂性材料的宏观破碎结果与能量耗散之间的关系与天然岩石材料有一定相似性，为今后3D打印材料模拟天然岩体应用于动态力学试验的可行性奠定了基础。     

风险矩阵法在A水泥工厂风险分级的应用初探

本文介绍“风险矩阵法”进行风险分级工作的基本思路，结合水泥厂的生产特点通过危险有害因素辨识，获得危险源分布情况，采用风险矩阵法对风险进行评估，按风险值将风险等级划分为重大风险、较大风险、一般风险和低风险，为水泥生产企业的安全风险分级工作提供参考。     

Understanding enhancing mechanism of Pr6O11 and Pr(OH)3 in methanol electrooxidation

The presence of oxygen vacancies and hydroxyl groups are both favorable for the methanol electrooxidation on Pt-based catalysts.Understanding and differentiating the enhancing mechanism between oxygen vacancies and hydroxyl groups for high activity of Pt catalysts in methanol oxidation reaction(MOR)is essential but still challenging.Herein,we developed two kinds of co-catalyst for Pt/CNTs,Pr₆O₁₁is rich in oxygen vacancies but contains substantially no hydroxyl groups,while Pr(OH)₃ possesses abundant hydroxyl groups without oxygen vacancies.After a seque nce of designed experiments,it can be found that both oxygen vacancies and hydroxyl groups can improve the performance of Pt/CNTs electrocatalysts,but the enhancing mechanism and improving degree of oxygen vacancies and hydroxyl groups for the MOR are different.Since the oxygen vacancies are more conducive to increasing the intrinsic activity of the Pt catalyst,and the hydroxyl groups play a decisive role in dehydrogenation and deproto nation of methanol,the co-catalysts with both oxygen vacancies and hydroxyl groups mixed with Pt/CNTs have higher catalytic performance.Therefore,hydroxyl-rich Pr₆O₁₁·xH₂O was prepared and used as MOR electrocatalyst after mixed with Pt/CNTs.Benefiting from the synergistic effect of oxygen vacancies and hydroxyl groups,the Pr₆O₁₁·xH₂O/Pt/CNTs shows a high peak current density of 741 mA/mg,which is three times higher than that of Pt/CNTs.These new discoveries serve as a promising strategy for the rational design of MOR catalysts with low cost and high activity.     

量子线性卷积及其在图像处理中的应用

线性卷积在图像处理中发挥着重要作用,但是在处理海量高分辨率图像时,求解线性卷积会消耗许多计算资源.为此,本文就量子线性卷积及其在图像处理问题中的应用开展相关研究,首先提出单通道,单位步长,零补充情况下的量子一维和二维线性卷积,然后实现多通道,非单位步长,非零补充的情况,最后将量子二维线性卷积应用于量子图像平滑,量子图像锐化和量子图像边缘检测.通过理论分析证明了量子线性卷积的空间复杂度O（logM）和时间复杂度O（log²M）较经典线性卷积有指数级下降,且基于Qiskit的仿真实验成功验证了量子线性卷积和量子图像处理算法的正确性和可行性.     

基于随机搜索树法的机械臂视觉伺服研究

在当今的工业应用中,机械臂完成某一特定作业任务的基础是进行轨迹规划。针对单纯基于图像的视觉伺服(the image-based visual servoing,IBVS),不能直接对相机或机械臂的运行轨迹进行控制,容易造成跟踪目标脱离视野、机械臂与工作空间障碍物相碰撞的问题,本文提出了三维随机搜索树算法(the three-dimensional Rapidly-exploring Random Trees algorithm,3D-RRT)实现机械臂的轨迹规划,将轨迹规划与视觉伺服相融合,使机械臂在跟踪移动过程中,满足图像视野范围限制和空间障碍物约束问题。在MATLAB平台建立算法仿真实验,结果表明三维随机搜索树算法(3D-RRT)可以较好解决基于图像的视觉伺服(IBVS)中存在的问题。     

样品温度对在线pH计测量的影响

在线分析仪表的种类繁多，在工业中的应用日趋广泛。作为其中的一类分析仪表，无论按被测介质的相态来划分，还是按照测量原理来划分，在线pH计通常都被划分为简单的一类分析仪表，掌握pH计的维护一般都会作为在线分析仪表从业者技能的最低要求。然而，pH计的测量原理实际上非常复杂，运行过程中也会出现种种问题需要解决。这其中样品温度的变化导致的测量误差会经常发生。本文就着重对于样品温度对于在线pH计的影响情况进行了探讨并给出了解决方法。     

Dynamic hierarchical collaborative caching scheme in ultra-dense networks

Pushing popular contents to the edge of the network can meet the growing demand for data traffic, reduce latency and relieve the pressure of the backhaul. However, considering the limited storage space of the base stations, it is impossible to cache all the contents, especially in ultra-dense network ( UDN). Furthermore, the uneven distribution of mobile users results in load imbalance among small base stations (SBSs) in both time and space, which also affects the caching strategy. To overcome these shortcoming, the impact of the changing load imbalance in UDN was investigated, and then a dynamic hierarchical collaborative caching (DHCC) scheme was proposed to optimize latency and caching hit rate. The storage of the SBS is logically divided into the independent caching layer and the collaborative caching layer. The independent caching layer caches the most popular contents for local users爷interest, and the collaborative caching layer caches contents as much as possible for the benefit of content diversity in the region. Different SBSs have respective storage space layer division ratios, according to their real-time traffic load. For SBSs with heavy load, the independent caching layers are allocated with more space. Otherwise, the collaborative caching layers could store more contents with larger space. The simulation results show that, DHCC improved both transmission latency and hit rate compared with existing caching schemes.