A liquid helium temperature target with a 10 K vapor shield for shock compression experiment in the environment condition of 100 Pa

The shock compression experiment of liquid helium is an available way to gain properties of specimen at high temperatures and pressures.Based on Fluent,a thermal insulation analysis and design of a liquid helium temperature target in the environment condition of 100 Pa for shock compression experiment is performed.Then,a cryogenic target with a 10 K helium vapor shield and a separated vacuum interval is particularly developed.A lowest temperature of 3.63 K and a stable temperature of 3.70 K in the specimen cavity with an accuracy of 0.1 K are obtained by means of continuous flow and vacuum cooling.Both time-consuming and temperature stability are well-suited to the requirements of the shock compression experiment.The results show that the calculated and experimental data well-matched each other.The simulation method may be effective and feasible for the optimal design of the cryogenic target.     

基于Soft多结构元素形态学的TM图像边缘检测

基于传统的数学形态学边缘检测算法,改进结构元素,提出Soft多结构元素算子。针对TM图像中存在噪声多和边缘形态多样性的特点,构建多结构元素,并结合Soft形态学方法,对TM图像进行形态学的腐蚀和膨胀,实现遥感图像的边缘检测。     

构件内部裂缝缺陷的有限元三维重建

提出了利用有限元的网格生成方法来实现构件内部裂缝缺陷的三维重建算法。首先,将边缘检测算法和基于种子填充的区域生长算法相结合,准确定位出裂缝的形状,提高重建的精度;其次,应用8节点的六面体单元格创建出裂缝模型,直接利用等方性体素建模,节约了计算成本;最后,对模型中的节点分类,针对不同种类的节点分别进行光顺处理。试验结果表明,该算法实现了对构件内部裂缝缺陷的三维空间形态的观察,弥补了以往算法只进行面重建的不足,提供了构件质量判定依据。     

The varied foraging mode of the subtropical eublepharid gecko Goniurosaurus kuroiwae orientalis

Insectivorous lizards usually employ one of two foraging modes, ambush ‘sit-and-wait’ or active ‘widely foraging’, but in the Gekkonomorpha the situation has been unclear. Therefore we quantified the foraging mode of the eublepharid gecko Goniurosaurus kuroiwae orientalis on Tokashikijima near Okinawajima, Japan, in September 1999. The taxon is rare, endangered and protected. On the selected semi-urban study site the gecko was confirmed as a nocturnal cursorial gecko, which also ascends trees up to 1.8 m. Foraging regimes of marked individuals, during repeated 30-min observation periods, could vary from immobility throughout, to active locomotion 84% of the time. Foraging mode was not significantly affected by sex, body length, mass or state of tail regeneration of the individuals, or by the timing of the observation. In males, at higher temperatures single moves became longer, while time allocated to moving was stable. In both sexes longer observation bouts included longer sitting pauses, which, given stable move duration, reduced the share of time spent moving and the moves per minute. Goniurosaurus kuroiwae orientalis averaged moving during 23% of the time, moving 0.39 times per minute, the moves lasting 77 s and the pauses lasting 745 s. Compared to other geckos, G. k. orientalis may be defined as a widely foraging animal, despite its mixed behaviour. This result supports the definition of the Eublepharidae as widely foraging and is compatible with two hypotheses, that early Gekkonomorpha were widely foraging or that they had an intermediate, undefined, foraging mode.     

Decision fusion recognition based on modified evidence rule

A modified evidence combination rule with a combination parameter λ is proposed to solve some problems in D-S theory by considering the correlation and complement among the evidences as well as the size and intersection of subsets in evidence. It can get reasonable results even the evidences are conflicting. Applying this rule to the real infrared/millimetre wave fusion system, a satisfactory result has been obtained.     

汉语语音剪裁效应初探

在话音插空(TASI和DSI)系统中,不可避免地会出现语音的首部剪裁、中部剪裁和尾部剪裁现象。这种剪裁现象如果不能被控制在适当的范围内,就会影响话音的质量和可懂度。因此,掌握剪裁现象对话音质量影响的规律,尽可能地把这种影响控制在人们觉察不出的范围内,是话音插空技术中一个主要研究课题。本文给出了一个利用微型计算机进行话音突发首部剪裁实验的方案。通过对实验结果的分析,试图给出汉语普通话语音首部剪裁对话音质量和可懂度影响的规律。     

流固耦合管道系统的模态分析和汽蚀监测

运用数值计算和试验研究相结合的方法对流固耦合管道系统进行了模态分析,并将其用于轴流泵的汽蚀共振分析,从而提出了水泵汽蚀监测的振动分析法。     

分布式数据库死锁检测协议

为解决分布式数据中,由于文件加锁的冲突而引起死锁的问题。这类死锁产生的充要条件是在它的请求图中有一有向回路,本文中提出了两个死锁检测协议。协议1适用于一般分布式数据库,它只要求进行一次通讯,且只要求传送一个表的信息;协议2 是针对巨型系统的,是一个层次协议。