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991.
应用遥编程的大时延遥操作技术 总被引:4,自引:0,他引:4
如何克服通信线路中的大时延和有限带宽,是空间遥机器人面临的最重要的一个问题.本文
阐述了应用遥编程技术提高大时延遥操作的稳定性和操作精度的基本思想.提出了一种将操
作区分段,采取复合控制策略的遥操作方法.同时介绍了基于遥编程概念的遥操作实验系统
的设计及其试验结果. 相似文献
992.
993.
Yu. I. Zhuravlev I. B. Gurevich E. M. Romanov H. Niemann V. A. Ivanov 《Pattern Recognition and Image Analysis》2006,16(4):656-658
Proceedings of the 7th International Conference on Pattern Recognition and Image Analysis: New Information Technologies (PRIA-7-2004)18–23 October, 2004, St. Petersburg, Russian Federation Revised papers
From the editors 相似文献994.
995.
Motif analysis for automatic segmentation of CT surface contours into individual surface features 总被引:2,自引:0,他引:2
This paper presents a new layer-based technique for automatic high-level segmentation of 3-D surface contours into individual surface features through motif analysis. The procedure starts from a contour-based surface model representing a composite surface area of an object. For each of the surface contours, a relative turning angle (RTA) map is derived. The RTA map usually contains noise and minor features. Algorithms based on motif analysis are applied for extracting a main profile of the RTA map free from background noise and other minor features. All feature points on the extracted profile are further identified from the extracted main profile through further motif analysis. The original contour is thus partitioned into individual segments with the identified feature points. A collection of consecutive contour segments among different layers form an individual 3-D surface feature of the original composite surface. The developed approach using motif analysis is particularly useful for the identification of smooth joins between individual surface features and for the elimination of superposed noise and unwanted minor features. 相似文献
996.
997.
Creep is investigated under a uniform stress state with allowance for the micropolar creep of the following materials: lignostone (T=293°K), steel ON2M (T=773° K), and an AIMgSi aluminum alloy (T= 293° K) understate and cyclic tension, i.e., atA
= a/m = 0, 0.25, and 0.5. It is established that for lignostone, the microstrains I11 are two orders lower than 212 in torsion, and the values of 2l12 are only a half order lower than 11 in tension. The creep strain of lignostone is described using nonlinear theory of viscoelasticity. For alloys and metals under static creep, the value of Iij is two or three orders lower than ij A qualitative change in microipolar creep occurs in the case of dynamic loading: whenA
= 0.5,the ratio of values of fatigue creep rate 2112/12 = 0.2.A subject investigated in 1990 with funding provided by the Ministry of National Education.Translated from Problemy Prochnosti, No. 12, pp. 18–23, December, 1993. 相似文献
998.
The article describes an automated system for scientific research Mekhanika devised at the Institute of the Strength of Materials, Academy of Sciences of the Ukraine; the system is suitable for almost complete automation of routine operations in data processing of mechanical experiments connected with the calculation of the state of stress and strain of the test specimen, presenting the results of the calculation in the form of tables and graphs, and with the calculation of the required mechanical characteristics of the material. In addition the system offers the user great possibilities in generalizing the results of experiments, constructing various analytical approximations of the obtained data. The results of experiments and calculations can be stored in a specialized data bank.Translated from Problemy Prochnosti, No. 3, pp. 71–79, March, 1993. 相似文献
999.
Summary Microindentation experiments have recently shown that silicon can exhibit plastic flow when subjected to high pressure. Assuming that under these conditions the relevant reference structure is the -Sn high-pressure phase of silicon, we apply the magic-strain concept to explore the space of configurations that could describe the observed behavior. We use first-principles total-energy calculations (including full relaxation of the atomic basis for every structure) to evaluate the relevance of strained configurations. Using this approach, we were able to identify a low-energy path that corresponds to planar flow of the atoms. The atomic configurations along this path provide insight into possible microscopic motions under high pressure that may be relevant to plastic flow in silicon. 相似文献
1000.
单漂移聚束器的非标准聚束模式 总被引:3,自引:2,他引:1
单漂移聚束器标准聚束模式要求粒子注入能量和聚束器漂移管的几何尺寸之间必须满足严格的条件,严重地限制了可聚束粒子的种类。文章论述了采用非标准聚束模式的方法,计算不同粒子在HI-13串列加速器上实现脉冲聚束的可行性。 相似文献