SNCR烟气脱硝系统多模型GPC-PID串级预测控制

针对SNCR烟气脱硝系统的大惯性、大迟延与时变等特性,提出了一种应用于不同典型工况下的GPC-PID串级预测控制方法.首先采用系统辨识的方法建立各典型工况下的SNCR脱硝系统的局部模型;其次依据二次最优控制原理设计各典型工况下的GPC-PID控制器参数;最后对各典型工况下的控制方法进行仿真研究,并研究各典型工况下GPC...     

Optical coherent dot-product chip for sophisticated deep learning regression

Optical implementations of neural networks (ONNs) herald the next-generation high-speed and energy-efficient deep learning computing by harnessing the technical...     

肉苁蓉低聚糖提取工艺的研究

以内蒙古阿拉善盟出产的肉苁蓉为实验材料,对肉苁蓉低聚糖的提取工艺进行了研究,通过L9(34)正交实验,确定最佳工艺参数为浸提液pH为11,时间为90min,温度60℃,料液比为1∶25,浸提次数为2次。      

四川盆西平原区裸土扬尘中Pb、Cd化学形态的生物有效性

为探究四川盆西平原区裸土扬尘中Pb、Cd总质量分数与其生物有效性的规律,在构建的"阳离子型污染物土壤表层运移行为研究系统"内进行模拟起尘试验,对土壤样品进行Pb、Cd模拟污染试验,结果表明:试验条件下,四川盆西平原区裸土扬尘颗粒物中Pb、Cd的总质量分数随着粒径的减小而增大,其中Pb的化学形态以碳酸盐结合态为主(44....     

Studying interconnections between two classes of two-stage fuzzy optimization problems

In this paper, we study two types of risk aversion two-stage fuzzy optimization problems. The first type is called two-stage fuzzy minimum risk problem (FMRP), while the second type is referred to as two-stage fuzzy value-at-risk problem (FVRP). In order to facilitate the solution of the two optimization problems, it is required to study the properties of FMRP and FVRP as well as their relationships. For this purpose, we first discuss the semicontinuity about the recourse function of two-stage FMRP. After that, we discuss the interconnections between optimal objective value of FMRP and that of FVRP, and the relationships between optimal solution of FMRP and that of FVRP. Using the obtained results, it would be possible to solve one two-stage optimization problem indirectly by solving its counterpart.     

基于微博重复发送的垃圾用户甄别

针对微博平台上的垃圾用户甄别问题,本文提出了基于微博重复发送行为的垃圾用户行为建模和甄别算法。在真实微博垃圾用户数据分析的基础上,本建模方法综合考虑了微博垃圾用户的行为信息、社交网络信息和文本信息,从不同的角度对垃圾用户进行了分析和建模。在真实数据集上的实验证明了方法的有效性,并且对模型中若干参数进行了优化,同时也分析了垃圾用户行为信息、社交网络信息和文本信息对模型的影响程度。     

基于面向时间过程的静态安全分析

针对传统静态安全分析基于单一时间断面、无法细致反映系统状态变化的不足,本文提出了一种面向时间过程的静态安全分析方法。首先介绍了面向过程方法的基本概念。充分利用丰富的电力系统测量和负荷预测数据信息,提取了描述每个时间断面的特征向量;结合电力系统负荷连续变化的特点,通过改进的K-means聚类分析技术,对负荷曲线进行了时间过程的划分。定义了提取时间子过程最大特征断面和最小特征断面的指标,并对特征断面的显著代表性进行了研究。在保证电网安全稳定的前提下,本文方法可一定程度上提高传输线路的利用率。最后,IEEE30节点算例表明面向时间过程静态安全分析方法的合理性和有效性。     

Solution-phase chemical route to branched single-crystalline CdS nanoarchitectures and their field emission property

A facile solution chemical method is developed to prepare hierarchical branched single-crystalline CdS architectures. A mechanism of “nucleate-aggregate-grow-ripen-separate” process is proposed to illustrate the growth of the CdS architectures. The obtained branched CdS architectures exhibit superior FE properties with the lower turn-on field (Eto) of 7.1 V μm⁻¹ at a current density of 10 μA cm⁻², and threshold field (Ethr) of 8.3 V μm⁻¹ at a current density of 100 μA cm⁻², which shows that the obtained products have greatly potential application as FE devices.     

Spray-drying of alumina powder for APS: effect of slurry properties and drying conditions upon particle size and morphology of feedstock

In this paper, effects of variables concerning slurry properties and drying conditions on the particle size and morphology of feedstock were discussed. The results indicated that, the increase of powder loading increased D ₅₀ and volume content but reduced recovery rate slightly. Other variables, such as inlet temperature, showed a maximum on the desired property. The particle size of resulting feedstock increased with the rise of feeding rate of slurry, however, decreased with the increase of atomization pressure based on the premise that atomization pressure was enough to force slurry to form the liquid membrane. For preparation of spherical feedstock, optimized variables were as follows: 60 wt.% powder in slurry, 2 wt.% PVA in slurry, inlet temperature of 60°C, atomization pressure of 13 × 10³ KPa and feeding rate of 12 ml min^?1. The volume content of feedstocks with 10–45 μm was above 65% and for D ₅₀ it was 15·42 μm. In addition, according to the heat and mass transfer equation, the drying mechanism was established, which was well in agreement with the experimental results.