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61.
陆刚 《铝加工》2005,(6):45-49
介绍了铝、镁、钛合金材料的性质及特点,指出铝、镁、钛材料在汽车工业中的应用和发展前景。  相似文献   
62.
从典型人物看《红楼梦》,我们除了看到封建文化腐朽落后的一面,更看到民族传统文化有价值的一面。典型人物的服饰体现了古代高度的服饰文明;典型人物的人文生活反映了物质文明和精神文明;典型人物所具有的谦和、孤傲、慈善等性格集中代表了中国人的文化性格;典型人物之间有礼有序又不失亲切温和的伦序关系是人情美的体现,具有审美价值。  相似文献   
63.
Igor S. Pandzic   《Graphical Models》2003,65(6):385-404
We propose a method for automatically copying facial motion from one 3D face model to another, while preserving the compliance of the motion to the MPEG-4 Face and Body Animation (FBA) standard. Despite the enormous progress in the field of Facial Animation, producing a new animatable face from scratch is still a tremendous task for an artist. Although many methods exist to animate a face automatically based on procedural methods, these methods still need to be initialized by defining facial regions or similar, and they lack flexibility because the artist can only obtain the facial motion that a particular algorithm offers. Therefore a very common approach is interpolation between key facial expressions, usually called morph targets, containing either speech elements (visemes) or emotional expressions. Following the same approach, the MPEG-4 Facial Animation specification offers a method for interpolation of facial motion from key positions, called Facial Animation Tables, which are essentially morph targets corresponding to all possible motions specified in MPEG-4. The problem of this approach is that the artist needs to create a new set of morph targets for each new face model. In case of MPEG-4 there are 86 morph targets, which is a lot of work to create manually. Our method solves this problem by cloning the morph targets, i.e. by automatically copying the motion of vertices, as well as geometry transforms, from source face to target face while maintaining the regional correspondences and the correct scale of motion. It requires the user only to identify a subset of the MPEG-4 Feature Points in the source and target faces. The scale of the movement is normalized with respect to MPEG-4 normalization units (FAPUs), meaning that the MPEG-4 FBA compliance of the copied motion is preserved. Our method is therefore suitable not only for cloning of free facial expressions, but also of MPEG-4 compatible facial motion, in particular the Facial Animation Tables. We believe that Facial Motion Cloning offers dramatic time saving to artists producing morph targets for facial animation or MPEG-4 Facial Animation Tables.  相似文献   
64.
This paper presents an innovative approach called box method for feature extraction for the recognition of handwritten characters. In this method, the binary image of the character is partitioned into a fixed number of subimages called boxes. The features consist of vector distance (γ) from each box to a fixed point. To find γ the vector distances of all the pixels, lying in a particular box, from the fixed point are calculated and added up and normalized by the number of pixels within that box. Here, both neural networks and fuzzy logic techniques are used for recognition and recognition rates are found to be around 97 percent using neural networks and 98 percent using fuzzy logic. The methods are independent of font, size and with minor changes in preprocessing, it can be adopted for any language.  相似文献   
65.
提出了智能渔场系统的具体设计方案.该设计方案由主控制器和分布在现场的数据控制单元组成,它们均采用微控制器AT89C51做为微处理器.为提高系统性能,为其配备了汉字和语音输出功能.主控制器和现场控制单元的通信协议设计简单、易于实现.同时,为了保证数据传输的正确性而采用海明校验,它能够定位和自动纠正一重错,具有很高的可靠性.该智能渔场系统在实验室已调试成功.实验结果表明,本系统结构设计合理,功能完善,可靠性高.  相似文献   
66.
古文字字库建设的几个问题   总被引:1,自引:1,他引:1  
随着古文字信息化处理研究的发展,古文字的标准字库建设已经显得十分迫切。本文探讨了古文字标准字库建设中需要注意的四个方面的问题:通过建立古文字资料库,穷尽性地收集整理古文字字形保证字形收集的全面性,通过拓片扫描造字保证所造字形的准确性;在字形与字之间建立对应关系时须考虑两者之间的异用、歧释、异体等复杂关系;字形归纳过程中应遵循形体的归并原则和区别原则;字符进入标准字符集时的分级应根据字频原则和形频原则。  相似文献   
67.
基于汉语二字应成词的歧义字段切分方法   总被引:5,自引:0,他引:5  
文章提出了利用汉语中的二字应成词,计算汉语句内相邻字之间的互信息1及t-信息差这两个统计信息量的新方法,进而应用这两个统计量,解决汉语自动分词中的歧义字段的自动切分问题。实验结果表明,采用该文所述的方法,对歧义字段的切分正确率将达到90%,与其他分词方法相比较,进一步提高了系统的分词精度,尤其与文献1所述方法比较,对于有大量汉语信息的语料,将降低系统的时间复杂度。  相似文献   
68.
A handwritten Chinese character recognition method based on primitive and compound fuzzy features using the SEART neural network model is proposed. The primitive features are extracted in local and global view. Since handwritten Chinese characters vary a great deal, the fuzzy concept is used to extract the compound features in structural view. We combine the two categories of features and use a fast classifier, called the Supervised Extended ART (SEART) neural network model, to recognize handwritten Chinese characters. The SEART classifier has excellent performance, is fast, and has good generalization and exception handling abilities in complex problems. Using the fuzzy set theory in feature extraction and the neural network model as a classifier is helpful for reducing distortions, noise and variations. In spite of the poor thinning, a 90.24% recognition rate on average for the 605 test character categories was obtained. The database used is CCL/HCCR3 (provided by CCL, ITRI, Taiwan). The experiment not only confirms the feasibility of the proposed system, but also suggests that applying the fuzzy set theory and neural networks to recognition of handwritten Chinese characters is an efficient and promising approach.  相似文献   
69.
并联机器人汉字球面雕刻刀路规划研究   总被引:1,自引:0,他引:1  
目前,将并联机构应用于未来加工领域的研究已成为热点,并联机器人以其结构优势在高刚度、高强度和高精度等场合将得到广泛应用,但关于并联机器人在汉字雕刻领域的研究尚未展开。该文研究了并联机器人在球面雕刻汉字所遇到的若干问题,包括平面刀路向球面刀路的映射方法、圆弧插补及刀具姿态实时规划算法等,给出了算例并用实验室拥有的6—PURU并联机器人进行了验证,结果表明文中所提方法是有效和可行的,从而对扩大并联机器人的应用范围奠定了基础。  相似文献   
70.
Effective teaching should focus the attention of learners to its essential aspects. It follows that instructional software can be designed in such a way that allows learners to experience the important variations in the critical aspects of the content to be learned. This paper reports on the experience of designing such special kinds of instructional learning objects for the learning of Chinese characters. The design of these learning objects takes into consideration not only what Chinese characters are all about but also how learners commonly make errors while they learn to write the characters. Out of the analysis of these learners' errors, variations in the structural features of Chinese characters were pulled out and embodied in the design of the learning objects. Learners tinkering with the learning objects can thus implicitly develop a sense of the structural features or regularity of Chinese characters, which most importantly should prepare the learners to learn more new characters in the future. The main proposal of this paper is the notion of this variation‐affording instructional software that allows learners to attend to the essential aspects of what is to be learned. Furthermore, the idea of the learning object also differs from other instructional software in its small, self‐contained and reusable nature, such that teachers can flexibly embed the learning objects into their own teaching materials.  相似文献   
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