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981.
982.
Industrial control applications are usually developed in two phases: control design and real-time system implementation. In the control design stage a regulator is obtained and later it is translated into an algorithm in the implementation phase. Traditionally, these two phases have been developed in separate ways. Recently, some works have pointed out the necessity of the integration of the control design and its implementation. One of these works reduce the delay variance of control tasks (defined as the control action interval (CAI) and data acquisition interval (DAI) parameters) splitting every task into three parts. The CAI reduction method highly reduces the delay variance and improves the control performance. This work shows how to evaluate these delays under static and dynamic scheduling policies. A new task model is proposed in order to reduce the CAI and DAI parameters, which implies an improvement in the control performance. The new task model will be implemented in a real process, and the experimental measurements will show how, effectively, the control performance is highly improved with the methods presented in this paper. 相似文献
983.
This paper surveys recent findings in neuroscience regarding the behavioral relevancy of the precise timing with which real
spiking neurons emit spikes. The literature suggests that in almost any system where the processing-speed of a neural (sub)-system
is required to be high, the timing of single spikes can be very precise and reliable. Additionally, new, more refined methods
are finding precisely timed spikes where previously none where found. This line of evidence thus provides additional motivation
for researching the computational properties of networks of artificial spiking neurons that compute with more precisely timed
spikes.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
984.
Sang-Cheol Park Author Vitae Author Vitae Seong-Whan Lee Author Vitae 《Pattern recognition》2004,37(4):767-779
In this paper, we propose a new method for estimating camera motion parameters based on optical flow models. Camera motion parameters are generated using linear combinations of optical flow models. The proposed method first creates these optical flow models, and then linear decompositions are performed on the input optical flows calculated from adjacent images in the video sequence, which are used to estimate the coefficients of each optical flow model. These coefficients are then applied to the parameters used to create each optical flow model, and the camera motion parameters implied in the adjacent images can be estimated through a linear composition of the weighted parameters.We demonstrated that the proposed method estimates the camera motion parameters accurately and at a low computational cost as well as robust to noise residing in the video sequence being analyzed. 相似文献
985.
In magnetic hard disk drive system, an ultra thin layer of lubricant is coated to the thin film media surface to prevent wear. Under the condition of relative motion, the displacement and replenishment of the lubricant at the head and media contact area are the factors that control the friction and wear behavior of the system. In this study, we investigate the sliding wear disk surface prepared by contact-start-stop (CSS) test using TOF SIMS (Time of Flight Secondary Ion Mass Spectrometry). TOF SIMS is a power tool for surface analysis with both high spatial and high mass resolution. Our investigations show that the lubricant thickness variation of the disk media at the contact area can be captured by sharp ion map images of TOF SIMS, and the thickness can be inferred based on the relative ion fragment intensity. In addition, the composition variation of the slider material and the magnetic layer materials can also be monitored. Finally the sliding effect is analyzed. 相似文献
986.
目前国外高级轿车普遍使用电控可变配气杌构,其功率性、经济性、安全排放性均达到欧洲四号标准,笔者对电控可变配气杌构的结构与工作原理进行论述,以期能尽快在国内普及。 相似文献
987.
Solid Works是基于Windows平台的三维设计软件。介绍了Solid Works的COM接口及其开发方法,并通过利用开发工具Visual C++6.0开发的一个简单例子来讲述如何用其对Solid Works进行二次开发。 相似文献
988.
We report here the first results of the application of confocal scanning laser microscopy (CSLM) for the study of the microstructure of solid industrial materials. Glass-fibre-reinforced composites, heterogeneous and conductive polymers, homogeneous as well as heterogeneous catalyst (precursor) specimens and soils were examined. We conclude that both the fluorescence and reflection modes of CSLM can yield valuable information. In particular, the optical sectioning capability of CSLM appears to be of great value as it enables one to access the 3-D organization of the specimen without the need for a difficult and time-consuming specimen preparation procedure. However, local obscuration may be an important factor in confocal image formation, limiting the penetration capabilities of the technique for industrial materials. 相似文献
989.
基于可达域的激光增材制造装备人机界面布局优化研究 总被引:1,自引:0,他引:1
由于激光增材制造装备具有多维度信息、多流程、多功能、多对象等人机交互特征,导致其人机交互效率低、舒适安全性差,直接影响制件成形质量的稳定性。基于此,提出一种基于可达域的激光增材制造装备人机界面布局优化方法。依据双手垂直可达域的舒适性划分人机交互界面可达域等级,构建基于可达域的激光增材制造装备人机界面布局优化模型。针对基于域模型构建的多决策变量界面布局模型求解问题,提出一种基于狼群-粒子群算法的混合智能求解算法,将狼群算法的奔走围攻行为机制引入粒子群算法,解决粒子群算法因种群多样性较低而导致计算结果容易陷入局部最优解问题。最后,以LDM4030激光增材制造装备为例,对其人机界面布局进行优化,并进行工效学仿真与眼动试验,结果表明:优化后的人机界面布局在舒适性、安全性以及界面的合理性上都优于原装备的设计,验证了该模型的有效性和可行性。 相似文献
990.