空心半螺栓球节点的弹塑性分析研究

采用２０节点３在元对一种新型空心半螺栓球节的弹塑性变形状态进行了有限元分析,通过节点的电测试验,证明了文中所述理论分析方法是正确的,指出了该节点有待改进之处。     

Development of Deep-Learning-Based Single-Molecule Localization Image Analysis

Recent developments in super-resolution fluorescence microscopic techniques (SRM) have allowed for nanoscale imaging that greatly facilitates our understanding of nanostructures. However, the performance of single-molecule localization microscopy (SMLM) is significantly restricted by the image analysis method, as the final super-resolution image is reconstructed from identified localizations through computational analysis. With recent advancements in deep learning, many researchers have employed deep learning-based algorithms to analyze SMLM image data. This review discusses recent developments in deep-learning-based SMLM image analysis, including the limitations of existing fitting algorithms and how the quality of SMLM images can be improved through deep learning. Finally, we address possible future applications of deep learning methods for SMLM imaging.     

Chronic-Antibiotics Induced Gut Microbiota Dysbiosis Rescues Memory Impairment and Reduces β-Amyloid Aggregation in a Preclinical Alzheimer’s Disease Model

Alzheimer’s disease (AD) is a multifactorial pathology characterized by β-amyloid (Aβ) deposits, Tau hyperphosphorylation, neuroinflammatory response, and cognitive deficit. Changes in the bacterial gut microbiota (BGM) have been reported as a possible etiological factor of AD. We assessed in offspring (F1) 3xTg, the effect of BGM dysbiosisdysbiosis in mothers (F0) at gestation and F1 from lactation up to the age of 5 months on Aβ and Tau levels in the hippocampus, as well as on spatial memory at the early symptomatic stage of AD. We found that BGM dysbiosisdysbiosis with antibiotics (Abx) treatment in F0 was vertically transferred to their F1 3xTg mice, as observed on postnatal day (PD) 30 and 150. On PD150, we observed a delay in spatial memory impairment and Aβ deposits, but not in Tau and pTau protein in the hippocampus at the early symptomatic stage of AD. These effects are correlated with relative abundance of bacteria and alpha diversity, and are specific to bacterial consortia. Our results suggest that this specific BGM could reduce neuroinflammatory responses related to cerebral amyloidosis and cognitive deficit and activate metabolic pathways associated with the biosynthesis of triggering or protective molecules for AD.     

基于自适应重采样的同步定位与地图构建

就移动机器人同步定位与地图构建展开研究,针对FastSLAM算法产生的粒子退化及粒子集重采样问题,提出了基于自适应重采样的FastSLAM算法。该算法首先计算粒子集的有效样本数,确定粒子退化程度。然后设定有效样本阈值,当有效样本数小于阈值时则进行重采样。仿真表明:与EKF-SLAM相比,基于自适应重采样FastSLAM重采样效率更高,鲁棒性更好,在机器人路径和陆标位置的估计上,也具有更高的精度。     

Adiabatic shear failure in brittle solids

Recent studies have revealed microscopic amorphous lamella resulting from inelastic deformation in the ballistic impact of boron carbide ceramic. The possibility that these deformation features are a consequence of adiabatic shear deformation in the impact event is explored. An early theory of adiabatic shear that was limited to the response of rigid-plastic deformation is expanded to include elastic strain energy. The study reveals that elastic strain energy is commonly a small, but not negligible, contribution to impact-induced adiabatic shear in metals. Elastic strain energy is paramount in brittle solids. Relations are developed from the theory to predict the nominal width and spacing of adiabatic shear-bands in brittle solids. Comparisons of the theoretical predictions are consistent with observations of impact-induced deformation features in boron carbide.     

基于Tikhonov正则化的WSN多边定位算法研究

节点定位是无线传感器网络实现监测和跟踪的一个重要前提.针对多边定位中的不适定问题.提出了一种基于Tikhonov正则化方法的定位算法,研究了定位模型的建立、正则化参数的选取方法以及最优定位参考点数的选取等问题.实验结果表明本算法与典型的极大似然估计法相比,较大幅度地提高了定位精度,当a值选取600,采用5个参考节点时,定位精度可达到1米.     

广州体育学院体育馆大跨度复杂钢网架及屋面施工技术

广州体育学院体育馆是广州亚运会篮球比赛专用场地,总建筑面积约14270m2,总高21.6m,建筑结构设计新颖,为空间网架结构,采用正放四角锥螺栓球连接,跨度和面积较大,分项工程较多,工期紧。通过科学制定施工方案,严格控制测量精度,合理安排各分项工程的施工进度,满足业主对进度质量的要求。     

基于TCP/IP的家庭能耗监控系统

针对家庭用户无法了解家庭内部具体用电情况的现状,提出了一种基于TCP/IP协议的家庭能耗监控系统。详细阐述了该系统的总体设计框架,给出了系统的硬件电路以及软件设计流程。该系统能够实现家庭能耗的实时监测与控制,具有免布线、组网简单、成本低等优点。     

Three-dimensionally confined excitons and biexcitons in submonolayer-CdSe/ZnSe superlattices

We report on structural and optical investigations of submonolayer-CdSe/ZnSe superlattices with varying thicknesses of the ZnSe spacer layers. High-resolution electron microscopy images demonstrate the formation of two-dimensional nanoscale CdSe islands for submonolayer-CdSe depositions. The vertical island arrangement is anti-correlated for spacer layer thicknesses exceeding 30Å, while predominantly vertically correlated growth occurs for thinner spacers. The different vertical ordering of the CdSe islands results in two clearly distinguishable lines in photoluminescence and optical reflectance spectra, which are attributed to excitons localized in quantum dots (QDs) formed by vertically coupled and uncoupled (Cd,Zn)Se islands, respectively. δ-like emission of single QDs is demonstrated and the different carrier localization in uncoupled and coupled QDs is reflected in the polarization of the edge emission. Stimulated emission and resonant waveguiding effects are observed for both states. At the highest excitation densities, we observe saturation of the stimulated emission in edge geometry attributed to saturation of localized states.