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991.
992.
993.
BP神经网络隐层单元数的确定方法及实例 总被引:2,自引:0,他引:2
针对BP神经网络隐层单元数不易确定的问题,提出一种在传统的经验公式基础上快速确定隐层单元数的方法。该方法首先借助经验公式确定隐层单元数的取值范围,然后将其扩大,在这个扩大的范围内寻找最优值。以BP神经网络预测交通流量为例,解释说明了具体的步骤,以及网络模型的隐层结构对模型仿真精度的影响。结果表明,采用该方法可快速决定隐层单元数,在实例中采用16个隐层单元数为最佳。 相似文献
994.
HyungKi Hong JaeKyeong Yoon Moojong Lim 《Journal of the Society for Information Display》2009,17(7):567-572
Abstract— The dynamic performance of displays is an important characteristic for multimedia applications. Motion‐picture response time (MPRT) has been used as an indicator of the dynamic performance of LCDs. This paper describes a comprehensive method of MPRT evaluation for the oblique viewing direction. By using a tilted camera configuration, the angular dependency of MPRT is investigated for the condition that the horizontally scrolling patterns are observed from the vertical direction. For each gray‐to‐gray transition, distinct changes in MPRT and the luminance profile of blur are observed. 相似文献
995.
Wenyu Qu Masaru Kitsuregawa Hong Shen Zhiguang Shan 《Journal of Network and Computer Applications》2009,32(2):423-432
The exponential expansion of the Internet and the widespread popularity of the World Wide Web give a challenge to experts on reliable and secure system design, e.g., e-economy applications. New paradigms are on demand and mobile agent technology is one of the features. In this paper, we propose a fault-tolerance execution model by using of mobile agents, for the purpose of consistent and correct performance with a required function under stated conditions for a specified period of time. Failures are classified into two classes based on their intrinsic different effects on mobile agents. For each kind of failure, a specified handling method is adopted. The introduction of exceptional handling method allows performance improvements during mobile agents’ execution. The behaviors of mobile agents are statistically analyzed through several key parameters, including the migration time from node to node, the life expectancy of mobile agents, and the population distribution of mobile agents, to evaluate the performance of our model. The analytical results give new theoretical insights to the fault-tolerant execution of mobile agents and show that our model outperforms the existing fault-tolerant models. Our model provides an effective way to improve the reliability of computer systems. 相似文献
996.
Ping Zhou Tianyou Chai Hong Wang 《Automation Science and Engineering, IEEE Transactions on》2009,6(4):730-743
During the operation of a grinding circuit (GC) in mineral processing plant the main purpose of control and optimal operation is to control the product quality index, namely the product particle size, into its technically desired ranges. Moreover, the grinding production rate needs to be maximized. However, due to the complex dynamic characteristics between the above two indices and the control loops, such control objectives are difficult to achieve using existing control methods. The complexity is reflected by the existence of process heavy nonlinearities, strong coupling and large time variations. As a result, the lower level loop control with human supervision is still widely used in practice. However, since the setpoints to the involved control loops cannot be accurately adjusted under the variations of the boundary conditions, the manual setpoints control cannot ensure that the actual production indices meet with technical requirements all the time. In this paper, an intelligent optimal-setting control (IOSC) approach is developed for a typical two-stage GC so as to optimize the production indices by auto-adjusting on line the setpoints of the control loops in response to the changes in boundary conditions. This IOSC approach integrates case-based reasoning (CBR) pre-setting controlling, neural network (NN)-based soft-sensor and fuzzy adjusting into one efficient control model. Although each control element is well known, their innovative combination can generate better and more reliable performance. Both industrial experiments and applications show the validity and effectiveness of the proposed IOSC approach and its bright application foreground in industrial processes with similar features. 相似文献
997.
Investigation of viscosity effect on droplet formation in T-shaped microchannels by numerical and analytical methods 总被引:1,自引:1,他引:0
Both numerical and analytical models have been developed to explore the viscosity effect of the continuous phase on drop formation
at a T-shaped junction in immiscible liquids. The effects of the generalized power law coefficient, the power law exponent
and the yield stress on the mechanism of drop breakup, final drop size and frequency of drop formation are studied by using
the numerical three-dimensional volume of fluid model. Droplets coalescence in Bingham fluids is observed in the beginning
transient period. The effect of yield stress on drop extension is also discussed. Predictions of drop size by using an analytical
force balance show satisfactory agreement with simulation results for Newtonian and power law fluids with different viscosity
ratios. The approximation error associated with the analytical model for Bingham fluids is also acceptable. This analytical
model can greatly shorten the prediction time as compared with the numerical model, which is helpful for on-line control. 相似文献
998.
The information resources on the Web are diversified, the amount of which is increasing rapidly. Demands for selecting useful
information from the Internet, managing personal contents, and sharing contents under control have risen. In this study, we
propose the Ubiquitous Personal Study, a framework of personalized virtual study to support accessing, managing, organizing,
sharing and recommending information. In this paper, we focus on discussing the framework, and design and implementation issues
on how to implement it with Web 2.0 mash-up technology and Open Source Software. 相似文献
999.
浅谈加密技术在企业信息化中的应用 总被引:1,自引:0,他引:1
加密技术是信息安全中的核心技术,在信息安全中的地位举足轻重.因此,如何在企业信息化中有效地利用加密技术也变得越来越重要.本文从应用的角度,阐述了加密技术在企业信息化中如何有效地应用加密技术,以确保人们工作生活中信息的安全. 相似文献
1000.
提出了一种新的基于亚像素边缘定位技术的棒状物体直径测量方法;该方法利用两个CCD摄像头,分别获得两张棒状物体横截面的椭圆特征图像,利用仿射变换将灰度椭圆特征图像变换成圆形特征图像,然后利用亚像素中的Zernike正交矩对边缘进行精确定位,进而分别计算出棒状物体的直径,再将两个测量数据加以平均融合,完成对直径的测量;实验结果表明,与像素级方法相比较,该方法定位精度高,测量误差小,能够达到提高测量精度的目的。 相似文献