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1.
文章通过对光纤有线电视网络采用1550nm/1310nm叠加组网方式的介绍,提出在大中城市对现有1310nm光纤网络改造,拓广,以及开展多功能增值业务带宽扩展的实现方案,并对1550nm直接光放大与1310nm二级级联组网方式的成本造价做出了比较。 相似文献
2.
1 引言地球物理方法是一种间接的方法,仅指示地球物质的一定特性。对于地球的最外层,即岩石圈,其结构只能通过综合运用调查区内各种地球物理方法来确定。种种地球物理技术的结合可减少资料解释中的模棱两可和前后不一致。目前,地热方法在多学科综合研究中似乎还只起有限作用。但是,也有一些利用地热资料的成功研究,尤其是在内力作用和地热条件关系方面的研究,表明未来的这项研究前景广阔,地热在多学科方法中的作用在未来可能将会改变。 相似文献
3.
近十余年来,重建沉积盆地的地热史和流体压力史方面的研究已取得重大进展。首先,把张性盆地的成盆机制描述为与岩石圈热事件相伴的,其后继以后裂谷期的热消散的原始地壳变薄作用。此模型解释了地壳变薄及上地壳脆性拉伸之类的定性观测结果,并为定量重建张性盆地的沉降史与热流史提供了工具。由于确定构造沉降量要比直接测定古温度方便易行, 相似文献
4.
运用神经网络对氧气顶吹转炉自动化进行动态预报[韩国]S.Y.Yun等1前言在氧气顶吹转炉工艺中,决定操作成功与否的关键是钢水温度和杂质量的控制,因而,要对其进行动态控制。本文介绍一种新的数学方法即以神经网络为基础建立的用于氧气顶吹转炉工艺控制的新型动... 相似文献
5.
Current applications of electronic performance monitoring based on job design theories that consider worker performance rather than stress issues are likely to generate unsatisfying and stressful jobs (Smith et al, 1986). This study examines critical job design elements that could influence worker stress responses in an electronic monitoring context. A questionnaire survey of employees in telecommunications companies representative of each region in the United States examined job stress in directory assistance, service representative and clerical jobs with specific emphasis on the influence of electronic monitoring of job performance, satisfaction and employee health. Useable surveys were received from 745 employees representing seven operating companies and AT & T; a response rate of about 25%. The results of this survey indicated that employees who had their performance electronically monitored perceived their working conditions as more stressful, and reported higher levels of job boredom, psychological tension, anxiety, depression, anger, health complaints and fatigue. It is postulated that these effects may be related to changes in job design due to electronic performance monitoring. 相似文献
6.
Parallel 2-d convolution on a mesh connected array processor 总被引:2,自引:0,他引:2
In this correspondence, a parallel 2-D convolution scheme is presented. The processing structure is a mesh connected array processor consisting of the same number of simple processing elements as the number of pixels in the image. For most windows considered, the number of computation steps required is the same as that of the coefficients of a convolution window. The proposed scheme can be easily extended to convolution windows of arbitrary size and shape. The basic idea of the proposed scheme is to apply the 1-D systolic concept to 2-D convolution on a mesh structure. The computation is carried out along a path called a convolution path in a systolic manner. The efficiency of the scheme is analyzed for windows of various shapes. The ideal convolution path is a Hamiltonian path ending at the center of the window, the length of which is equal to the number of window coefficients. The simple architecture and control strategy make the proposed scheme suitable for VLSI implementation. 相似文献
7.
本文首先简述湘潭电厂除、排灰情况,粉煤灰加工工艺和品质,然后较详细地用文字和图表表述该粉煤灰在水工工程、泵送砼工程、路面工程、砂浆及轻质砼中的应用。 相似文献
8.
9.
Sung J Ghahramani Z Bang SY 《IEEE transactions on pattern analysis and machine intelligence》2008,30(12):2236-2242
Variational Bayesian Expectation-Maximization (VBEM), an approximate inference method for probabilistic models based on factorizing over latent variables and model parameters, has been a standard technique for practical Bayesian inference. In this paper, we introduce a more general approximate inference framework for conjugate-exponential family models, which we call Latent-Space Variational Bayes (LSVB). In this approach, we integrate out model parameters in an exact way, leaving only the latent variables. It can be shown that the LSVB approach gives better estimates of the model evidence as well as the distribution over latent variables than the VBEM approach, but in practice, the distribution over latent variables has to be approximated. As a practical implementation, we present a First-order LSVB (FoLSVB) algorithm to approximate this distribution over latent variables. From this approximate distribution, one can estimate the model evidence and the posterior over model parameters. The FoLSVB algorithm is directly comparable to the VBEM algorithm and has the same computational complexity. We discuss how LSVB generalizes the recently proposed collapsed variational methods [20] to general conjugate-exponential families. Examples based on mixtures of Gaussians and mixtures of Bernoullis with synthetic and real-world data sets are used to illustrate some advantages of our method over VBEM. 相似文献
10.
郑军 《数字社区&智能家居》2009,(8)
计算机信息化促进了各个领域的发展,但目前由于不能使用常规输入法输入集外汉字,直接影响到了许多领域的信息化建设。要想设计一种输入集外汉字的输入工具,就必须要搞清楚TrueType字体技术和TrueType字库格式。 相似文献