双微导管“跨区”栓塞颅内不规则动脉瘤

【摘要】 目的 探讨双微导管跨区域栓塞技术治疗颅内不规则动脉瘤的可行性。方法 回顾性分析2016年5月至2017年5月连续采用跨区栓塞技术治疗的19例颅内不规则动脉瘤患者临床资料，对栓塞策略制定、栓塞材料选择、手术过程及栓塞效果进行初步总结。结果 19例患者颅内不规则动脉瘤治疗均获成功，其中1例在手术收尾阶段填塞瘤颈时因弹簧圈突入载瘤动脉过多，最后经植入支架补救成功。跨区栓塞技术成功率为95%，完全栓塞15例，次全栓塞3例。结论 双微导管技术跨区栓塞治疗颅内某些特定不规则动脉瘤，操作简单，是一种安全有效的治疗选择。

     

施工过程中建筑质量的控制

项目建设的施工阶段是整个建设项目的工作主体,也是将设计实现的实施阶段。项目施工的过程中,工程建设设计的实现、工程现场施工的监督以及工程建设原材料和设备的管理等等,对于工程的建设结果都有着重要的意义,要保证建筑工程的顺利建设和质量,做好建筑项目施工过程中的质量控制是其中的重要组成部分。     

西门子LOGO!在汽车试验场交通灯系统中的应用

阐述以西门子LOGO!为控制核心的交通灯控制系统的组成、硬件配置、控制流程及软件实现。     

Human performance evaluation of user interfaces for spatially-constrained text portrayal and access

To maximize visualization effectiveness, graphical data are commonly augmented with text to provide detailed information and define specific values. This text is often displayed in a pop-up dialog box pertaining to an object, permitting simultaneous display of the object and associated alphanumeric information. However, a human operator performance cost may be incurred when the resulting portrayal occludes critical information within the visualization. To address this issue, we developed and evaluated three alternative, spatially constrained, text portrayal techniques. These techniques and their associated access interface were designed to reduce occlusion while providing rapid access to desired alphanumeric data. Each technique was evaluated against the pop-up dialog using a dual-task human performance paradigm. Performance measures included accuracy, response time, display occlusion, and subjective feedback. The basis for the spatially-constrained text access technique design, their implementation affordances, and limitations are discussed. The alternative techniques and their user interface concepts resulted in mixed accuracy and response time performance compared to the pop-up dialog. Specific design features reduced data access time to one third of the time required to access the spatially-constrained text access techniques. Overall, equivalent performance was obtained among the variants while the potential for occlusion was reduced during use of the novel designs.     

基于色差聚类的原木图像端面检测与统计

针对自然环境下外界因素对原木截面检测的干扰,使用图像处理技术,以自然环境中原木堆放存储时图像为处理对象,设计了一种原木截面识别方法。通过色差值聚类将原木图像分割为原木截面、孔隙及背景,去除背景干扰提取原木端面;采用逐级开运算与改进分水岭算法,对端面进行分割计数。实验结果表明:在自然环境下的正检率91.88%,错检率5.08%,漏检率8.12%,满足了原木截面识别计数的需求。     

Effect of rheological properties of catalyst slurry on the structure of catalyst layer in PEMFC

The dispersion process significantly influences the dispersion of catalyst slurry in proton exchange membrane fuel cells (PEMFCs). The particle size distribution and rheological properties of clusters in slurry directly affect the catalyst layer's coating state, surface morphology, and structure. This paper prepared four different catalyst slurries by high shear emulsification, homogenization, ball milling, and ultrasonic methods. The average particle sizes of clusters in slurry were 725, 337, 452, and 1098 nm, respectively. The rheological properties of catalyst slurry prepared by several dispersion processes are different. Amplitude scanning test demonstrates that yield stresses of slurries prepared by shear, homogenization, ball milling, and ultrasonic methods are 0.047, 0.185, 0.133, and 0.136 Pa, respectively. The viscosity of catalyst slurry is the lowest when prepared by the shear method and is the highest when prepared by the ultrasonic method, and the slurry prepared by homogenization and ball milling methods has the best thixotropy. By observing the catalyst layer, the slurry cluster prepared by the homogenization method has small particles, a strong network structure, and good thixotropy, producing a flat catalyst layer and fewer cracks. Electrochemical tests demonstrate that the catalyst layer with the smoothest surface morphology, the smallest cluster particles, and fewer cracks leads to higher polarization performance. The output voltage of the ink prepared by the homogenization method can reach 0.726 V under the condition of 1000 mA cm^?2.     

Crystal structure and lithium ionic transport behavior of Li site doped Li7La3Zr2O12

Doping some elements on Li site of LLZO is an effective method to stabilize it as cubic phase and improve Li⁺ conductivity. The reported possible Li site elements calculated by first principle are Be, B, Al, Fe, Zn, Ga and the Ga-doped LLZO shows the a higher conductivity than other LLZO. However, whether these elements all can stable LLZO as cubic phase are needed to be verified and the reason of Ga exhibits higher conductivity is not clear enough. In this work, all these elements are tried to be doped on Li site and the results show that the Al, or Fe, or Ga can stable LLZO as cubic phase while the others does not. The Ga-doped LLZO exhibits the highest conductivity of 1.31×10⁻³ S•cm^-1 due to the transform of group space from Ia-3d to I-43d, shorter distances between different Li⁺, and Ga can improve the grain size.     

无卤阻燃线性低密度聚乙烯技术的研究进展

综述了近几年国内外线性低密度聚乙烯(LLDPE)阻燃体系的研究现状,包括磷系、硅系、无机氢氧化物、膨胀型以及近几年迅速发展的纳米级阻燃剂;分析了各类无卤体系阻燃的机理以及研究进展。最后对LLDPE的阻燃前景进行展望,纳米级阻燃剂将是未来的研究热点。     

变压器高压套管色谱异常分析

分析了一起220kV电容式油纸高压套管色谱异常的故障原因,并提出了预防措施。     

等效循环电池组剩余使用寿命预测

电动汽车以零污染、零排放等优点成为新能源汽车中最具有发展潜力的对象，锂离子电池作为其动力来源，科学准确地预测其剩余使用寿命是决定电动汽车性能的重要因素。本文研究等效循环电池组在等效循环工况、不同循环次数时，锂离子电池电压随着放电时间的变化曲线。通过分析不同循环次数下导函数在等效特征点处的斜率变化规律，建立锂离子电池等效循环工况下的寿命退化曲线。选取NASA等效循环电池组和自测JZ等效循环电池组，将放电初期和放电后期曲线与特定斜率直线交点作为等效循环寿命预测的等效特征点，根据这两组特征点分别建立退化模型Mini和Mlat。最后选取等效循环电池组内的其他电池进行锂离子电池等效循环寿命预测的验证。通过锂离子电池测试数据集验证其预测精度较高，稳定性较好，具有较强的应用价值。