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91.
直驱式螺杆泵驱动装置是国内新出现的一种螺杆泵地面驱动装置,设计的ZLBQ55型直驱式螺杆泵驱动装置与常规地面驱动装置异步电机+减速机构的驱动方式不同,是利用低速、大扭矩电机直接驱动抽油杆柱。介绍了该装置的设计参数、结构、控制系统和整机试验。 相似文献
92.
93.
罗晓晔 《锻压装备与制造技术》2007,42(2):76-79
分析了不锈钢骨架的6道分离与成形工艺,集2次冲孔,3次成形,1次切开在一副多工位级进模具中。论述了骨架的多工位级进精密模具的结构特点及工作原理。对制件的排样、导料、轴向导钉定位、高度定距钉定位、模具的成形件设计、导向件设计、卸料与顶件吹料装置设计进行了详细的阐述。本模具结构设计新颖,紧凑而精密。制件出料流畅且效率、精度高。 相似文献
94.
95.
The paper proposes a progressive viewing method useful in sharing a sensitive image. As in visual cryptography, this method
characterizes its ability to recover the image by stacking transparencies without any computation. However, the method balances
the sensitivity and the daily-processing convenience of the image.
The text was submitted by the authors in English.
Wen-Pinn Fang was born in 1971 in Taiwan, Republic of China. He received his BS degree in mechanical engineering from National Sun-Yet-Sans
University in 1994, and MS degree in mechanical engineering from National Chiao Tung University in 1998. In 2006 he received
his PhD in Computer Science Department of National Chiao Tung University. His recent research interests include image sharing
and image processing.
Ja-Chen Lin was born in 1955 in Taiwan, Republic of China. He received his BS degree in computer science in 1977 and MS degree in applied
mathematics in 1979, both from National Chiao Tung University, Taiwan. In 1988 he received his PhD in mathematics from Purdue
University, United States. In 1981–1982, he was an instructor at National Chiao Tung University. From 1984 to 1988, he was
a graduate instructor at Purdue University. He joined the Department of Computer and Information Science at National Chiao
Tung University in August 1988 and is currently a professor there. His recent research interests include pattern recognition
and image processing. Dr. Lin is a member of the Phi-Tau-Phi Scholastic Honor Society. 相似文献
96.
Morphological Pyramids in Multiresolution MIP Rendering of Large Volume Data: Survey and New Results
Jos B. T. M. Roerdink 《Journal of Mathematical Imaging and Vision》2005,22(2-3):143-157
We survey and extend nonlinear signal decompositions based on morphological pyramids, and their application to multiresolution maximum intensity projection (MIP) volume rendering with progressive refinement and perfect reconstruction. The structure of the resulting multiresolution rendering algorithm is very similar to wavelet splatting. Several existing classes of pyramids are discussed, and their limitations indicated. To enhance the approximation quality of visualizations from reduced data (higher levels of the pyramid), two approaches are explored. First, a new class of morphological pyramids, involving connectivity enhancing operators, is considered. In the pyramidal analysis phase, a conditional dilation operator is used, with a given number n of iterations. The corresponding pyramids for n = 0 and n = 1 are known as the adjunction pyramid and Sun-Maragos pyramid, respectively. We show that the approximation quality when rendering from higher levels of the pyramid does increase as a function of the number of iterations n of the conditional dilation operator, but the improvement for n > 1 is limited. The second new approach, called streaming MIP-splatting, again starts from the adjunction pyramid. The new element is that detail coefficients of all levels are considered simultaneously and are resorted with respect to decreasing magnitude of a suitable error measure. All resorted coefficients are projected successively, until a desired accuracy of the resulting MIP image is obtained. We show that this method outperforms the previous methods based on morphological pyramids, both with respect to image quality with a fixed amount of detail data, and in terms of flexibility of controlling approximation error or computation time.Jos B.T.M. Roerdink received his M.Sc. (1979) in theoretical physics from the University of Nijmegen, the Netherlands. Following his Ph.D. (1983) from the University of Utrecht and a two-year position (1983–1985) as a Postdoctoral Fellow at the University of California, San Diego, both in the area of stochastic processes, he joined the Centre for Mathematics and Computer Science in Amsterdam. There he worked from 1986–1992 on image processing and tomographic reconstruction. He was appointed associate professor (1992) and full professor (2003), respectively, at the Institute for Mathematics and Computing Science of the University of Groningen, where he currently holds a chair in Scientific Visualization and Computer Graphics. His current research interests include morphological image processing, biomedical visualization, neuroimaging and bioinformatics. 相似文献
97.
This paper reports preliminary work to investigate the suitability of using a blackboard framework as a problem-solving model for stamping process planning in progressive die design. The model is described at two levels: knowledge level and computational level. The knowledge level describes how the stamping process planning domain is represented in a blackboard architecture. The computational level describes how the blackboard architecture is modeled and implemented using object technology. A software prototype has been developed using CLIPS and C++ interfaced with Solid Edge CAD system. An example is presented to illustrate the feasibility and practicality of the proposed approach. 相似文献
98.
一种新的渐进式小波图像编码算法 总被引:1,自引:0,他引:1
在研究嵌入式零树小波算法的基础上提出了一种新的、适合网络使用的渐进式小波图像编码方法。它采用分层量化、分层编码、分层传输的方法,按照小波分解后系数的重要性逐层进行处理,可以同时使用阈值和层数两个参数来控制解码精度,逐渐恢复高质量的图像。实验表明,这种算法在相同压缩率时的峰值信噪比和嵌入式零树小波算法相比无太大差别,但在算法的效率上却明显高于嵌入式零树小波算法,而且编码端可以根据信道容量自适应地调整层数和阈值来控制数据量,特别适合于在网络环境中应用。 相似文献
99.
带属性的三角网格模型简化算法研究 总被引:10,自引:3,他引:10
在计算机视觉,计算机仿真,网络传输中,经常遇到带有颜色,纹理等属性的三角网格模型的简化问题,文中提出一种带属性的三角网格模型简化的算法,该算法将表征网格顶点信息的向量由简单的三维几何信息扩展到包含颜色,纹理等附加信息的多维向量,在R^n空间中用对称Hausdorff距离控制网络简化顺序和精度,既保证了简化网格模型在几何上与补始网格模型尽可能地相似,又较好地保存了初始网格模型的颜色,纹理等信息。 相似文献
100.
胡成武 《湖南工业大学学报》2002,16(4)
介绍了压簧片零件多工位连续模的设计过程 ,该模具采用自动送料机构送料 ,侧刃、导正钉控制步距 ,排样方式为双斜排排样。小凸模为快换形式 ,凹模采用镶套结构 ,模具结构合理紧凑 相似文献