基于FPGA的单端行波故障测距系统的设计与实现

针对现有的10 k V输电线单端行波故障测距理论,提出了一种基于Cyclone IV系列FPGA芯片EP4CE15F17C8N的软硬件实现方案。采用FPGA自顶向下模块化思想,设计了行波故障测距系统,采用AD7356进行高速数据采集,通过改进的凯伦鲍尔矩阵进行相模变换,用FIR滤波器IP核进行小波变换求模极大值,最后根据模极大值的极性选择测距公式计算故障距离。通过时序仿真和板级测试表明,该方案设计时序稳定,且定位精度高、实时性强。     

一种基于卫星导航的列车初始定位方法研究

在西北环境恶劣地区,线路区间往往较少设置实体应答器,列车在区间重启时需要长距离低速运行.经过实体应答器后才能确定列车位置。针对该问题.本文提出一种基于卫星导航系统和车载电子地图的列车初始定位方法。该方法利用轨道约束算法和概率学方法,设计满足铁路安全标准要求的列车初始定位方法。     

Automatic outer surface extraction of femoral head in CT images

Computer-aided hip surgery planning and implant design applications require accurate segmentation of femoral head and proximal acetabulum. An accurate outer surface extraction of femoral head using marching cubes algorithm remains challenging due to deformed shapes and extremely narrow inter-bone regions. In this paper, we present an automatic and fast approach for segmentation of femoral head and proximal acetabulum which leads to accurate and compact representation of femoral head using marching cubes algorithm. At first, valley-emphasized images are constructed from original images so that valleys stand out in high relief. Otsu’s multiple thresholding technique is applied to seperate the images into bone and non-bone classes. Region growing method and threedimensional (3D) morphological operations are performed to fill holes in the bone. In the reclassification process, the bone regions are further segmented, and the boundaries of the bone regions are further refined based on Bayes decision rule. Finally, marching cubes algorithm is applied to reconstruct a 3D model and extract the outer surface of femoral head and proximal acetabulum. Experimental results show that this method is an accurate segmentation technique for femoral head and proximal acetabulum and it can be applied as a tool in medical practice.     

氧化苦参碱对慢性肾脏病患者血清TGF-β1和Col Ⅲ的影响

目的观察氧化苦参碱对慢性肾脏病(CKD)患者血清转化生长因子-β1(TGF-β1)、Ⅲ型胶原(ColⅢ)的影响,探讨其在肾间质纤维化发生发展过程中的作用和治疗价值。方法选取健康对照者10例、慢性肾脏病患者40例,根据肾小球滤过率(GFR)分为轻度肾损害组(GFR<90 mL/min.1.73 m2,CKDⅠ)、中重度肾损害组(GFR<60 mL/min.1.73 m2,CKDⅡ),再分层随机抽样,分为常规治疗组和氧化苦参碱组。利用双抗体夹心酶联免疫吸附法分别检测各研究对象治疗前、后血清TGF-β1、ColⅢ含量,采用t检验比较两组TGF-β1、ColⅢ水平的差异。结果氧化苦参碱组TGF-β1、ColⅢ含量显著低于常规治疗组(P<0.05)。结论氧化苦参碱可能通过下调TGF-β1、ColⅢ水平,减少ECM沉积,从而达到防止肾间质纤维化的作用。     

雷达制导半实物仿真系统可信度分析

论文以末制导雷达半实物仿真系统为研究对象,在讨论可信度与VV&A关系基础上,对仿真系统开发各阶段不同模型开展可信度分析,主要是对不同模型开展V&V,并综合各VV结论进行,确保了雷达制导半实物仿真系统的高的可信度.通过该系统可信度分析总结给出了可信度的性质以及工程应用中半实物仿真系统可信度应遵循的几条原则.     

Prediction of Scour Depth around Offshore Pipelines in the South China Sea

Scour depth prediction of offshore pipelines is of great significance to the design and construction of the submarine pipeline projects. In this paper, based on the CFD software package FLUENT and User...     

复合地层下泥水盾构管片上浮规律及影响因素分析

针对在盾构隧道施工中经常出现的管片上浮问题,以南昌轨道交通4号线泥水盾构过江隧道为工程依托,通过数理统计方法对泥水盾构穿越不同地层时管片上浮量进行归纳分析,探讨地层参数以及盾构掘进参数对管片上浮的影响规律.研究结果表明:在全断面砂层中掘进,管片上浮量小且上浮值变化稳定;而当进入上软下硬地层和泥质粉砂岩层,管片上浮量急剧...     

Image Registration Technique for Assessing the Accuracy of Intraoperative Osteotomy for Pelvic Tumors by 3D-Printed Patient-Specific Templates

The study aimed to explore the feasibility of an image registration technique for assessing the accuracy of intraoperative osteotomy of pelvic tumors by 3-dimen...     

3D-Printed Porous Titanium Augments for Reconstruction of Massive Bone Defect in Complex Revision Total Knee Arthroplasty:Implant Design and Surgical Technique

Reconstruction of severe bone defects in revision total knee arthroplasty(TKA)remains a challenge for orthopaedists.The progression of medical imaging and addit...     

闭环控制在交通安全管理中的运用

现代管理理论认为,有效的管理活动应该是一个闭合的环,应该是一个持续改进与提高的过程.柳州恒达巴士股份有限公司运用PDCA的闭环控制模式来检查发现交通安全管理中的薄弱环节,并用"戴明环"理论来不断提升管理水平,并取得了较为明显的效果.