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11.
浅谈气泡混合轻质土的特点及应用 总被引:1,自引:0,他引:1
结合高速公路的发展,分析了气泡混合轻质土的设计机理,详细地介绍了气泡混合轻质土的工程特性,阐述了气泡混合轻质土在公路建设中的应用,最后对气泡混合轻质土的应用前景进行了展望。 相似文献
12.
A sensing strategy for the reverse engineering of machined parts 总被引:1,自引:0,他引:1
The reverse engineering of machined parts requires sensing an existing part and producing a design (and perhaps a manufacturing process) for it. We have developed a reverse engineering system that has proven effective with a set of machined parts. This paper describes the system, presents some results, and discusses strategy for a new system.This work was supported by ARPA under ARO grant number DAAH04-93-G-0420, DARPA grant N00014-91-J-4123, NSF grant CDA 9024721, and a University of Utah Research Committee grant. All opinions, findings, conclusions or recommendations expressed in this document are those of the authors and do not necessarily reflect the views of the sponsoring agencies. 相似文献
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14.
Douglas Walton 《Artificial Intelligence and Law》2006,14(3):177-239
In this paper it is shown how tools developed in argumentation theory and artificial intelligence can be applied to the development
of a new dialectical analysis of the speech act of making a proposal in a deliberation dialogue. These tools are developed,
modified and used to formulate dialogue pre-conditions, defining conditions and post-conditions for the speech act of making
a proposal in a deliberation dialogue. The defining conditions set out what is required for a move in a dialogue to count
as the making of a proposal by one of the parties. What is required are the conditions that (1) the move fit the requirements
of the argumentation scheme for practical reasoning, and (2) the premises are propositions describing common goals of both
parties or propositions that they reasonably consider means to achieve these goals. The analysis goes beyond the standard
speech act approach by specifying not only the normative requirements for making a well-formed proposal, but also the requirements
for responding to it by questioning or criticizing it, and the requirements for defending it. 相似文献
15.
Gerhard Jäger 《Journal of Logic, Language and Information》2002,11(4):427-451
In this paper, we discuss some formal properties of the model ofbidirectional Optimality Theory that was developed inBlutner (2000). We investigate the conditions under whichbidirectional optimization is a well-defined notion, and we give aconceptually simpler reformulation of Blutner's definition. In thesecond part of the paper, we show that bidirectional optimization can bemodeled by means of finite state techniques. There we rely heavily onthe related work of Frank and Satta (1998) about unidirectionaloptimization. 相似文献
16.
Temporal message-flow diagrams (TMFDs), alternatively called sequence charts, interaction diagrams, event traces, or actor diagrams, are illustrations of a system's global message-passing activity over time, and a pictorial aid to understanding the system's behavior. They are widely used for requirements and documentation for network protocols and object-oriented applications. We present a general formalism for TMFDs, describe a suite of tools we have designed that employs this formalism, and present our experiences with these tools. The formalism and tools described serve to support and broaden the use of TMFDs in developing communicating systems. 相似文献
17.
Hong ZHU 《Frontiers of Computer Science in China》2012,6(1):40-56
Meta-modelling plays an important role in model driven software development.In this paper,a graphic extension of BNF (GEBNF) is proposed to define the abstract syntax of graphic modelling languages.Fro... 相似文献
18.
文中提出了一种基于视频灰度直方图形状的Hashing算法,能有效抵抗各种常见的几何失真和视频处理操作.算法的鲁棒性原理如下:1)由于直方图的形状与像素位置无关,故基于直方图的视频Hashing算法能有效抵抗各种常见的几何攻击;2)由于在计算Hashing前对视频帧进行了平滑预处理,故算法对加噪攻击、模糊滤波、有损压缩等处理操作有很好的鲁棒性;3)由于计算Hashing前在时间轴上进行了低通滤波预处理,故算法能抵抗帧率变化、帧丢失等时域同步攻击.实验结果表明,所提出的Hashing算法有良好的唯一性和鲁棒性能. 相似文献
19.
随着手机GPS位置测定、导航以及摄像功能的普及,对于移动状态下的位置定位以及都市空间建筑物实时搜索等应用功能存在日益增长的需求。介绍了图像处理方式的城市建筑物识别方法,通过对两种图像匹配算法--SIFT和Local Search的比较分析表明,构造物轮廓线及其组合是一种相对稳定的几何特征,在匹配时受图像的仿射变换、画质变化以及镜头畸变等因素干扰较小,此外,基于轮廓的图像匹配指数还能反映摄影位置的变化。因此,对Local Search进行了改进,利用实时图的建筑物的特征轮廓线与从三维数据库中提取的建筑群特征轮廓线进行匹配,然后选择匹配指数高的记录作为识别结果。结果表明基于Local Search算法的建筑物识别技术可以很好地适应移动条件下建筑物快速识别的要求。 相似文献
20.
Emma P. Bullock Allison L. Roxburgh Patricia S. Moyer-Packenham Elif Bektas Joseph S. Webster Kathleen A. Bullock 《Journal of Computer Assisted Learning》2021,37(2):557-586
This study focused on an examination of how type, quality and children's awareness of design features in digital math games, along with an awareness of the mathematics goals of the game, were related to learning outcomes. We conducted a parallel conversion mixed methods study with 45 students in Grades 3 and 4 (ages 9–10). Students participated in clinical interviews using three digital math games. The results suggest a moderated mediation relationship in which the quality of the design features moderated the mediating impact of children's awareness of the game's design features, specifically when the child was aware of the mathematics content learning goal (MCLG) of the game. These findings show how important it is that design features are of high quality in a digital math game, and how this is intertwined with children's awareness of the features and the MCLG. When these variables intertwined in just the right way, the interactions between the children and the digital math game afforded mathematical learning growth. 相似文献