颗粒图像测速技术在离心试验变形分析中的应用

由于颗粒图像测速技术的可遥控性和实时性,可用于离心机试验中进行土体变形测量.将土体划分为若干细小单元,通过单元的颗粒组成纹理,可以追踪单元的位移,从而确定土体的变形.以此为依据,建立一套系统来实现离心机试验中土体模型的变形监测,包括高分辨率数码相机、精确控制点、土体可识别纹理.试验后对系列图片进行数字化处理,并对实验中产生的各种误差加以修正,得到需要的变形数据.基于测速技术原理的分析,该系统的位移测量精度可以达到0.04 mm,准确度0.02 mm左右.在砂土边坡的离心试验中应用该系统,分别量测模型边坡在离心加速度增加过程中产生的变形和地下水上升过程中渗流引起的变形,试验结果规律性好,可以反映模型土体各个位置不同时刻的位移情况.表明该系统适用于离心环境中的模型试验,是研究其完整物理过程的重要工具.     

关于对建筑工程质量检测管理改革的探讨(一)

结合对各地的建筑工程质量检测管理的调研,对我国建设工程检测管理体系的建立、工程检测技术的发展,以及工程检测在保证建设工程质量中的作用等进行了总结回顾;对目前建设工程检测行业的管理现状以及不足进行了分析,并提出了完善检测管理工作的建议。     

亚麻织物草酸酸洗加工工艺技术的研究

对亚麻织物前处理工艺中草酸酸洗工序进行了研究。通过正交试验筛选了工艺条件，确定了草酸酸洗的生产工艺，并对此进行了讨论：酸洗是亚麻织物前处理工艺中的重要工序，酸洗主要是利用草酸洗除亚麻织物中的铁、锰离子等杂质，减少双氧水的剧烈分解，起到降低亚麻织物强力损失的作用。     

分数Vasicek利率下创新重置期权定价

假定股票价格过程服从分数跳-扩散过程,利率满足分数Vasicek利率模型,利用分数跳-扩散过程理论以及保险精算方法,讨论了创新重置期权的定价问题,获得了创新重置看涨期权定价公式,推广了关于创新重置期权定价的相关结果.     

带双参数四次Said-Ball曲线的扩展

为了使曲线易于实现光滑拼接,同时具有对应于相同控制顶点的不同形状,定义了具有凸包性、对称性、形状可调性等基本性质的新曲线.文中分析了基函数及曲线的性质和2个形状参数的几何意义,给出了2条Said-Ball型曲线的G0,G1,G2连续拼接条件.类似构造了局部形状可调的组合曲面.数值实例说明了所给方法的正确性和有效性.     

500kV线路带电作业方法及工器具的应用

500kV线路电压等级高,杆塔类型多,各塔型塔头尺寸较通常情况复杂．造成带电作业过程中塔头承力工器具的通用性不好,不仅增加了工作难度和成本,同时也限制了带电作业的实践应用。为此,对进入强电场的绝缘工器具及作业方法进行摸索、改进和现场应用．包括更换ZM塔型直线绝缘子串的工器具改进、单柱绝缘爬梯的现场应用、500kV线路带电作业的现场应用等。     

THIN LAYER METHOD ANALYSIS OF SPOUTED BED DRIED MALAYSIAN PADDY – CHARACTERISTIC DRYING CURVES

A lab‐scale spouted bed dryer was used for the drying of paddy. The Malaysian grown paddy is a sample of Geldart's Group D particle. Drying was carried out in the dryer at two different internal configurations, namely with or without the installation of a draft tube, and at several drying temperatures (60–90C), air flow rates (1.14–1.45 m/s) and bed heights (30–45 cm). Drying kinetics of paddy in spouted bed showed only induction and falling rate periods, without constant drying rate period. Thin layer method analysis shows characteristic drying rate curves of linear and exponential functions for the first and second falling rate period, respectively, in conventional spouted bed drying. A single power function was observed in spouted bed drying with a draft tube, mainly as a result of a better tempering effect that gave a lower drying rate gradient.     

Linear optimal control problem of a system with circuit-free graph structure

We solve a linear optimal control problem with state and control restrictions by the method of region analysis, where the state equations describe the flow in a directed graph without a circuit. The results are used for the optimal control of a system of hydroelectric power plants.     

Diabetes and mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS): radiolabeled polymerase chain reaction is necessary for accurate detection of low percentages of mutation

A 6-yr-old boy presented with muscle weakness, lactic acidemia, and insulin-dependent diabetes mellitus (IDDM). Using PCR and restriction enzyme analysis, he was found to have the classical A3248G mitochondrial DNA (mtDNA) mutation frequently associated with mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS). The mutation was confirmed by sequencing muscle mtDNA. The mutation in mtDNA from muscle, lymphoblasts, and blood was clearly demonstrable by standard methods using ethidium bromide staining. His mother also had IDDM, but no A3243G mutation could be detected in her blood or transformed lymphoblasts using the same PCR technique. When PCR was carried out in the presence of [32P]deoxycytidine triphosphate, subsequent autoradiography detected the presence of the mutation at low levels in mtDNA from the mother's lymphoblasts and blood. Study of the mother's muscle showed a mitochondrial myopathy, despite the fact that she was asymptomatic. We emphasize that the increased sensitivity of radiolabeled PCR may be necessary to detect small percentages of heteroplasmic A3243G mtDNA mutation in blood from diabetic subjects. Otherwise the incidence of mtDNA mutations in both IDDM and non-insulin dependent diabetes may be underestimated.