火电厂主蒸汽压力的LQ次优调节策略

主蒸汽压力是火电厂热工自动化中非常重要的参数，但是具有大惯性、纯迟延等特性，是一个比较难调的对象。基于主蒸汽压力降阶近似模型和二次型最优控制原理，给出了主蒸汽压力的LQ次优调节策略。实验研究表明：该策略调节效果令人满意，非常适用于变压运行的机组。图7参3     

计算太阳能集热器性能的实用公式及其应用

给出计算太阳能集热器性能用的两个近似公式：并给出误差计算公式和应用举例。     

结构动力可靠度计算的修正条件反应法

基于反应时程分解的子集模拟法是计算受随机激励作用的结构小失效概率的高效算法,该法将失效域划分为子集序列,通过分解反应时程来生成子集计算所需的样本。条件反应法计算动力可靠度时,通过线性反应来估计非线性反应,或通过单自由度结构的反应来估计多自由度结构的反应。该文将基于反应时程分解的子集模拟法用于条件反应法中,提出修正的条件...     

改进的二阶统计量盲分离算法

利用二阶统计量(不同时延相关矩阵)的非平稳性和信号时序结构特征,能简单估计出线性瞬时混合的盲源信号。但随时延[τ]增大,仅利用某一个时延协方差均衡化,忽略了信号的时间变化特性,很难保证算法的性能。通过分析矩阵的平均特征,提出一种改进的基于二阶统计量盲源分离算法,对一组均衡化的时延相关函数进行等时延分段,并对等间隔段的两个时延矩阵分别求取均值,采用类似联合近似对角化,估计出最优化的酉矩阵,最终得到信源的稳健估计。性能指标分析和仿真实验证明,算法很好地解决原算法的不足,并成功分离出信号。     

推算边角网近似坐标的研究

提出了一种基于平面直角坐标系转换理论的求解边角网近似坐标的方法,论述了其基本原理,并以实例分析了该方法的可行性,最后给出了一些结论和建议。     

无线传感器网络(ε, δ)—近似Top-k查询处理算法

提出一种适合于任意数据分布的基于抽样的(ε,δ)–近似Top-k查询处理算法。其中,ε≥0和0≤δ<1分别是相对误差界和失败概率界。理论分析表明,对于任意ε≥0和0≤δ<1,该算法返回的查询结果的相对误差界大于ε/(1+ε)的概率小于δ。于是,该算法可以达到任意精度。同时,还给出了支持近似Top-k查询的优化的抽样算法,并通过节点上的数据过滤技术来减少通信能量的消耗。理论分析和仿真结果表明,提出的算法能量消耗低并且计算复杂度低。     

基于近似动态规划与零和博弈的空战机动决策

为应对机动策略未知的空中目标,针对以往机动决策建模通常存在"维数灾难"的不足,提出了一种结合近似动态规划与零和博弈的在线积分策略迭代算法.首先描述了近似动态规划存在问题及求解方法,提出了双人零和微分对策的近似动态规划算法,然后分析了博弈双方的均衡策略和在线策略迭代的求解方法,并结合空战应用场景设计了评价函数,最后进行了空战格斗的算例仿真.仿真结果表明,该算法通过运用函数逼近可以解决动态规划中难以处理的大规模模型"维数灾难"问题.     

基于盲恢复的POCS图像超分辨率重建

在传统凸集投影(POCS)算法基础上,考虑到算法对于初始图像的依赖性,尝试通过引入近似点扩散函数检测(APEX)盲解卷积技术,对POCS算法的初始参考图像进行盲恢复,然后再进行超分辨率图像重建。仿真实验证明,APEX盲恢复后的初始图像,相比原初始图像,更加接近真实图像。重建后,直观上图像的清晰度有了一定程度的提高,由于更好地抑制了噪声,表现在PSNR有了一定的提升;另外,由于APEX的引入,改进算法在一定程度上降低了原算法对初值的依赖程度,增强了POCS算法的鲁棒性。     

Evaporation Kinetics of Single Droplets Containing Dissolved Bioaiass

ABSTRACT

Luikov approach was applied to predict drying time and temperature of a droplet containing liquid substrate of entobacterin in the falling drying rate period. Analytical expressions describing both average and local temperatures of the particle in the drying process were derived and solved. Constants necessary to solve the equations, describing certain material properties and material moisture bonding were found in simple experiments. An experimental relationship of Rebinder number and moisture content of the material enabled to calculate changes of average droplet temperature in the falling drying rate period. Analytical solutions of heat transfer equations for shrinkage core model both for a linear and exponential change of moisture content of the droplet in the drying process were delivered. Employing experimental heat transfer coefficient, drying time and droplct temperature field were determined. Comparison of experimental and predicted drying times as well as droplet temperatures shows small discrepancy. Results obtained can be used to predict quality of labile products in the course of drying.     

Repelled from the wound,or randomly dispersed? Reverse migration behaviour of neutrophils characterized by dynamic modelling

Following neutralization of infectious threats, neutrophils must be removed from inflammatory sites for normal tissue function to be restored. Recently, a new paradigm has emerged, in which viable neutrophils migrate away from inflammatory sites by a process best described as reverse migration. It has generally been assumed that this process is the mirror image of chemotaxis, where neutrophils are drawn into the areas of infection or tissue damage by gradients of chemotactic cues. Indeed, efforts are underway to identify cues that drive neutrophils away by the reverse process, fugetaxis. By using photoconvertible pigments expressed in neutrophils in transparent zebrafish larvae, we were able to image the position of each neutrophil during inflammation resolution in vivo. These neutrophil coordinates were analysed within a dynamic modelling framework, using different forms of the drift–diffusion equation with model selection and parameter estimation based on approximate Bayesian computation. This analysis revealed the experimental data were best fitted by a model incorporating a diffusion term but no drift term—where the presence of drift would indicate fugetaxis. This result, for the first time, provides rigorous data-driven evidence that reverse migration of neutrophils in vivo is not a form of fugetaxis, but rather a stochastic redistribution.