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Haowei Zhang Junwei Xie Jiaang Ge Zhaojian Zhang Binfeng Zong 《European Journal of Operational Research》2019,272(3):868-878
A phased array radar (PAR) is used to detect new targets and update the information of those detected targets. Generally, a large number of tasks need to be performed by a single PAR in a finite time horizon. In order to utilize the limited time and the energy resources, it is necessary to provide an efficient task scheduling algorithm. However, the existing radar task scheduling algorithms can't be utilized to release the full potential of the PAR, because of those disadvantages such as full PAR task structure ignored, only good performance in one aspect considered and just heuristic or the meta-heuristic method utilized. Aiming at above issues, an optimization model for the PAR task scheduling and a hybrid adaptively genetic (HAGA) algorithm are proposed. The model considers the full PAR task structure and integrates multiple principles of task scheduling, so that multi-aspect performance can be guaranteed. The HAGA incorporates the improved GA to explore better solutions while using the heuristic task interleaving algorithm to utilize wait intervals to interleave subtasks and calculate fitness values of individuals in efficient manners. Furthermore, the efficiency and the effectiveness of the HAGA are both improved by adopting chaotic sequences for the population initialization, the elite reservation and the mixed ranking selection, as well as designing the adaptive crossover and the adaptive mutation operators. The simulation results demonstrate that the HAGA possesses merits of global exploration, faster convergence, and robustness compared with three state-of-art algorithms—adaptive GA, hybrid GA and highest priority and earliest deadline first heuristic (HPEDF) algorithm. 相似文献
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阵列探测器的像点亚像素定位精度 总被引:8,自引:0,他引:8
本文研究阵列探测器的像点亚像素定位精度与内插算法及像斑大小的关系,文中提出一种校正算法误差、提高定位精度的方法。上述分析和论述通过实验证明是正确的。 相似文献
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TR4终端高性能探测器系统 总被引:1,自引:0,他引:1
描述了兰州中能重离子加速器TR4终端装备的高性能探测器系统的结构性能.各类探测器都达到了很好的性能指标.Si多叠层望远镜,Z/△Z~50,△E/E~0.3%.IC+PSD+SPD+CsI(T1)对数密度望远镜,Z/△Z~44.5,△x~1.7mm.棉球面反射镜结构开始时间探测器装置,△t~140Ps.重离子飞行时间谱仪,A/△A~86,Z/△Z~48,△E/E~0.78%,△t~286ps.9单元和36单元CsI(T1)轻粒子小角度关联探测器阵列,Si+CsI(T1)轻粒子望远镜也达到了很好的性能指标.简述了小角度关联等实验结果. 相似文献
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增塑的PVC涂膜压电晶体传感器阵列用作香味传感系统曹忠,林辉概,王彬锋,王柯敏,陈泽忠,俞汝勤(湖南大学化学化工系,长沙,410082)关键词阵列,压电晶体传感器,增塑的PVC涂膜,香味传感系统吸附活性物质如类脂化合物等涂膜的压电晶体传感器(PCS)... 相似文献
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There is a compelling need to experimentally understand solder joint deformation behavior at high temperatures over an extended
period of time. Accordingly, the deformation behavior of solder joints in a Ceramic Ball Grid Array (CBGA) package mounted
on an organic FR4 board under extended dwell time at a high temperature has been studied using laser moiré interferometry.
The warpage and the in-plane horizontal deformation of the ceramic substrate and the organic board as a function of time were
determined. The variation of the normal strains and shear strains in the solder joints with time were also investigated. It
was found that increased sensitivity was necessary to accurately determine the strains in the small sized solder joints. A
new method utilizing carrier fringes to increase the sensitivity of the moiré interferometry system is proposed and has been
used to determine the strains in the small sized solder joints. Increased sensitivity can be obtained merely by changing the
incident angle of the laser light on the surface of the specimen, thereby making it unnecessary to use expensive phase shifting
apparatus with the traditional laser moiré system. 相似文献
27.
We extend in several directions a complete convergence theorem for row sums from an array of rowwise independent random variables obtained by Sung, Volodin, and Hu [8] to an array of rowwise independent random elements taking values in a real separable Rademacher type p Banach space. An example is presented which illustrates that our result extends the Sung, Volodin, and Hu result even for the random variable case. 相似文献
28.
This paper presented development work of an in situ method for damage detection in thin-wall structures using embedded two-dimensional ultrasonic phased arrays. Piezoelectric wafer active sensors were used to generate and receive guided Lamb waves propagating in the plate-like structure. The development of a generic beamforming algorithm that does not require parallel ray assumption through using full wave propagation paths is described. A virtual beam steering method and device, the embedded ultrasonic structural radar, was implemented as a signal post-processing procedure. Several two-dimensional configurations were investigated and compared with beamforming simulation. Finally, rectangular shape arrays were developed for verifying the generic formulas and omnidirectionality. The rectangular arrays yield good directionality within the 360° full range and are able to detect damage anywhere in the entire plate. 相似文献
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