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41.
Long-Wen Chang Shui-kung Chuag Shang-shung Yu 《Multidimensional Systems and Signal Processing》1994,5(3):319-330
The compression of Chinese characters is very important for Chinese office automation and desktop publishing. In this paper, various methods are used to compress 13,051 Chinese characters losslessly by coding their skeleton points. The skeleton points are composed of isolated points and curves. To trace every point in a curve once and consecutively is a NP problem. Therefore, we use contour path following and revisiting algorithms to trace skeleton curves with chain codes. The remaining isolated skeleton points are encoded by an Elias code. Our coding method has a better compression rate than that of conventional skeleton coding. 相似文献
42.
In this article we propose efficient scan path and BIST schemes for RAMs. Tools for automatic generation of these schemes have been implemented. They reduce the design effort and thus allow the designer to select the more appropriate scheme with respect to various constraints. 相似文献
43.
44.
本文着重分析和讨论了提高轧机工作机座刚度的三种途径: 合理提高零部件刚度、短应力线机座、预应力机座。指出某些错误概念与问题,阐述了如何正确地提高轧机工作座的刚度。 相似文献
45.
新型并条胶辊套筒的特点及运用 总被引:1,自引:1,他引:0
为了解决常规并条胶辊套筒存在的易发热、易漏油,芯轴易弯曲磨损以及保养、能耗等问题,介绍了新型免加油并条胶辊套筒的性能特点并以实际生产数据进行对比;说明实际使用该新型并条胶辊套筒综合效果好,具有省工省时、降低消耗、质量稳定、使用寿命长、总投资少等优点。 相似文献
46.
三峡永久船闸结构缝渗漏处理技术 总被引:1,自引:0,他引:1
在三峡永久船闸结构缝处理过程中,认真分析了结构缝渗漏的原因,通过止水检查槽进行压水检查,确定了渗漏部位。结合渗漏具体情况,采取了结构缝表面嵌填止水材料和廊道周边止水检查槽灌浆相结合的处理方法。在实施过程中,采用了多种新材料和新工艺,取得了良好的效果。 相似文献
47.
The cohesive model is used for the prediction of the crack path during stable crack extension in ductile materials. The problem of crack-path deviation is investigated by means of simulation of crack propagation in a round tensile bar. The respective phenomenon is known as cup-cone fracture. It is shown that the model is able to predict the failure mechanism, which consists of normal fracture in the center and combined normal/shear fracture in the so-called “shear lips” at the specimen’s rim. The damage evolution and crack path predicted by the model are presented. The effect of the normal and shear failure parameters on the crack-deflection point and several aspects of the finite element mesh are discussed. 相似文献
48.
49.
In this paper we propose a new protocol called time-space label switching protocol (TSL-SP) in optical burst switching (OBS), and define the terms time-space label (TSL) and time-space routing (TSR). An important concept of response time is introduced in the time label mechanism. The TSL-SP is a new technology that can quickly and efficiently forward data with a label on the optical networks. A two-dimension label switched path (TD-LSP) can be set up, that is maintained and deleted by the TSL-SP. For clearly illuminating the operation principles of the TSL-SP, we propose a new approach of orthogonal time-space coordinates in which the vertical coordinate is the space label and the horizontal coordinate is the time label. The proposed TD-LSP can dramatically reduce the routing failure probability and greatly improve the link network efficiency compared with other signaling protocols. Moreover, we define the time-space label control plane that can achieve the higher efficiency. When the TSL-SP is applied to networks, switching performance can be improved by two orders compared to the switching performance with the conventional OBS signaling protocols. The fundamental goal of TSL-SP is to band the signaling and routing functions together closely. Also, the TSL-SP can reduce the complexity of the network, support automatic service offering, and provide traffic engineering. 相似文献
50.
A model of economic dynamics under stable ecological balance conditions is proposed. A methodology of construction of an optimal growth path is constructed for this model. 相似文献