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1.
Multi-valued and universal binary neurons (MVN and UBN) are the neural processing elements with the complex-valued weights and high functionality. It is possible to implement an arbitrary mapping described by partially defined multiple-valued function on the single MVN. An arbitrary mapping described by partially defined or fully defined Boolean function, which can be non-threshold, may be implemented on the single UBN. The quickly converging learning algorithms exist for both types of neurons. Such features of the MVN and UBN may be used for solving the different problems. One of the most successful applications of the MVN and UBN is their usage as basic neurons in the Cellular Neural Networks (CNN). It opens the new effective opportunities in nonlinear image filtering and its applications to noise reduction, edge detection and solving of the super resolution problem. A number of experimental results are presented to illustrate the performance of the proposed algorithms.An erratum to this article can be found at 相似文献
2.
Z.M. Zhong J. Chen P. Zhong J.B. Wu 《The International Journal of Advanced Manufacturing Technology》2006,28(9):855-862
As the result of vibration emission in air, a machine sound signal carries important information about the working condition
of machinery. But in practice, the sound signal is typically received with a very low signal-to-noise ratio. To obtain features
of the original sound signal, uncorrelated sound signals must be removed and the wavelet coefficients related to fault condition
must be retrieved. In this paper, the blind source separation technique is used to recover the wavelet coefficients of a monitored
source from complex observed signals. Since in the proposed blind source separation (BSS) algorithms it is generally assumed
that the number of sources is known, the Gerschgorin disk estimator method is introduced to determine the number of sound
sources before applying the BSS method. This method can estimate the number of sound sources under non-Gaussian and non-white
noise conditions. Then, the partial singular value analysis method is used to select these significant observations for BSS
analysis. This method ensures that signals are separated with the smallest distortion. Afterwards, the time-frequency separation
algorithm, converted to a suitable BSS algorithm for the separation of a non-stationary signal, is introduced. The transfer
channel between observations and sources and the wavelet coefficients of the source signals can be blindly identified via
this algorithm. The reconstructed wavelet coefficients can be used for diagnosis. Finally, the separation results obtained
from the observed signals recorded in a semi-anechoic chamber demonstrate the effectiveness of the presented methods . 相似文献
3.
An ILRIS-36D 3-D laser image scanning system was used to monitor the Anjialing strip mine slope on Pingshuo in Shanxi province.The basic working principles,performance indexes,features and data collection and processing methods are illustrated.The point cloud results are analyzed in detail.The rescale range analysis method was used to analyze the deformation characteristics of the slope.The results show that the trend of slope displacement is stable and that the degree of landslide danger is low.This work indicates that 3-D laser image scanning can supply multi-parameter,high precision real time data over long distances.These data can be used to study the distortion of the slope quickly and accurately. 相似文献
4.
魏正曦 《四川轻化工学院学报》2010,(4):420-422
图像分割是运动目标检测与跟踪技术必须要解决的问题,在很多时候它涉及到图像阈值的选取。文章采用的算法首先计算图像中不同区域的灰度均值,结合最小差值条件,反复修订由计算所得的阈值,从而达到自动选优的目的。在此基础上,文章进一步给出了用C++语言实现算法的关键代码。测试表明此方法选择阈值简便实用,图像的二值化效果良好。 相似文献
5.
运动汽车图像静态视点平滑特征优化仿真 总被引:1,自引:0,他引:1
由于运动汽车图像在特征采集过程中,汽车处于高速运动状态,采集的过程无法与汽车完全同步,造成汽车的特征像素分量在高速运动中丢失,产生较大的像素运动噪声,使得汽车图像边缘高频特征因为运动干扰而模糊.传统的平滑过渡方法在对运动汽车图像进行平滑处理时,按照图像中像元灰度值计算突变特性,但受到像素丢失与噪声无法抑制的影响,无法解决运动汽车图像高频分量对图像像元灰度值的干扰问题.提出基于替身运动DR算法的运动汽车图像静态视点平滑过渡方法,用替身像素描述汽车在场景中的运动特征,替身像素在场景中运动并同其它汽车的替身进行交互,采用局部化的车辆模型提高运动汽车场景的逼真度,通过依据替身运动的平滑过渡算法完成归一化线性运动汽车图像静态视点的平滑过渡,解决了运动汽车图像的平滑过渡问题.实验结果说明,所提方法可确保运动汽车图像边缘锐化,有效处理平滑噪声和锐化边缘. 相似文献
6.
作为一种文学意象,“夜”经常出现在陈毅诗词中。在陈毅诗词中,由于创作时代背景和诗人创作心理,“夜”不仅是时空概念,更赋予了紧张战斗、自由思想、欢乐工作的丰富内涵,具有独特的表现特征和审美价值。通过对陈毅诗词夜意象的探析,可以探究陈毅诗词的艺术价值。 相似文献
7.
Titanium in the rapidly cooled hypereutectic gray iron 总被引:4,自引:0,他引:4
Y. Lerner 《Journal of Materials Engineering and Performance》2003,12(2):141-146
The effect of titanium on the structure and properties of a rapidly cooled hypereutectic cast gray iron has been studied on
the example of permanent mold (PM) casting. A microstructure study showed that titanium is a relatively strong element in
controlling solidification structure by increasing undercooling and thus promoting type D graphite. The effectiveness of titanium
additions depends on the base iron carbon equivalent (CE) with more pronounced changes in iron with a lower CE. The undercooling
ability of the titanium decreases after exceeding a certain level. Increasing titanium from 0.09–0.12% slightly increases
undercooling in iron with lower CE, but this effect was reduced in a more strongly hypereutectic iron. Alloying with titanium
generally improves tensile strength, but the effectiveness of titanium additions also depends on the base iron CE range. Scanning
electron microscope (SEM) studies revealed that most of the titanium-containing compounds were located in the metallic matrix:
titanium carbides have been found in pearlite, while titanium nitrides and carbonitrides were located in ferrite. The presence
of large amounts of extremely hard titanium-containing compounds, which often appear with steadite in a relatively high phosphorous
content PM gray iron, amplifies the negative effect of titanium on machinability. This study suggests that for optimal combination
of tensile strength/microstructure with good machinability, the titanium content in PM gray iron should not exceed 0.075%. 相似文献
8.
9.
学位具有学术价值、教育价值、管理价值等本体性价值,也具有个体价值与社会价值、工具性价值和目的性价值等派生性价值。当前人们在学位价值取向上存在着一些明显的错位和偏差。其具体表现有四点:一是重学位的“派生”性价值,轻学位的“本体”性价值;二是过分强调学位的教育价值和管理价值,而缺乏对学术价值应有地位的肯定;三是重学位的社会价值,轻学位的个体价值;四是重学位的工具性价值而忽视学位的目的性价值。导致这种错位现象产生的原因,不仅有教育系统内部因素,而且也与中国传统文化价值观和当前社会对人才的选拔、聘用政策有着直接的关系。 相似文献
10.
环境问题与经济问题紧密相连,由于环境问题的综合性和复杂性,需要运用系统工程的方法和经济学原理,将环境问题置于整个经济系统中统筹考虑,建立相对完整的环境经济系统工程方法体系,将环境保护工作纳入经济社会发展中,使其成为决策中主要考虑的因素之一,并引起应有的重视。本研究从环境与经济承载力、环境投资的经济分析、环境与投资效率比较、环境资源的经济价值以及生态补偿与污染赔偿等方面构建环境经济系统工程的基本框架体系,并结合实际进行案例分析。研究表明,单纯的政府行政干预不如创造条件,如补偿、税收减免、投资、贴息等,使其具备在市场规则下.自动引导资源向环境保护与污染治理的投入,如排污指标的交易等。此外,自然资源是不可或缺的稀有资本,应该将保护生态系统及生物多样性纳入各级政府决策的主要方面。 相似文献