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81.
计及综合需求响应的电热气互联能源系统环保经济优化调度 总被引:1,自引:1,他引:0
为促进综合能源系统多能协同互补互济,提高能效,以电热气互联能源系统为研究对象,提出了一种多目标协同优化的综合需求响应模型及运行策略求解算法.首先,设计了含综合需求响应的电热气互联能源系统架构,采用能量耦合矩阵对互联系统中多能转化关系进行描述,在分时能源价格机制下,构建了混合时间/空间尺度的多能协同综合需求响应数学模型.然后,以最小化的系统用能成本、环境成本和弃风弃光功率为目标,构建了环保经济优化调度模型,采用结合协同进化思想和非支配排序遗传算法的改进优化算法(Co-NSGA-Ⅱ)对模型进行求解.仿真结果表明,所提出的模型及优化运行策略能够有效提高多能系统间能量协调能力和综合需求响应能力. 相似文献
82.
针对配电自动化开关柜故障诊断对配电网安全性和可靠性的影响,提出一种基于模糊C均值聚类和灰色关联的配电自动化开关柜故障诊断方法.首先,该方法通过各类遥测信息分层影响因子,计算隶属度函数并采用AHP-熵权法确定权重完成配电自动化开关柜状态评价的分层模糊运算.然后,针对配电自动化开关柜典型故障信息,应用FCM法聚类后灰色关联分析,完成六类配电自动化开关柜典型故障的诊断,在保证诊断准确度的同时极大地减少了计算量.最后,对北京市某地区配电自动化开关柜故障信息的状态评价及故障诊断结果并与传统灰色关联分析对比表明,所提出方法的故障诊断准确度可达90%,为快速、准确、客观地实现对配电自动化开关柜状态的实时监测及智能电网自动化的进一步发展提供参考. 相似文献
83.
84.
松材病虫病是最紧迫的威胁之一,最近对中国针叶林造成了严重破坏,为了阻止松材病虫病的快速传播,必须在早期准确检测和计数受感染的树木。提出了一种基于密度图的方法,用于从高分辨率航拍图像中估计具有松材病虫病的树木数量,方法引入了阈值分割、形态处理和超像素技术,以最大限度地减少由于建筑物和岩石等相似背景物体引起的误差。实验表明,所提出的方法优于密度学习 算法,平均绝对误差、均方根误差和绝对误差方差分别从21.3、22.2和127.2减少到8.0、11.7和59.6,计数准确率从54.7%提高到81.3%。 相似文献
85.
国内核电厂吸取福岛事故的经验教训,增加了严重事故后应急补水设施,完善了应急补水的相关功能,进一步提高了核电厂的安全水平.对M 310核电机组严重事故状态下的应急补水设施进行技术分析,分析计算结果表明,应急水源到应急补水泵接入点距离过长,水损过大,实际补水压力及流量无法满足设计要求.针对该问题提出一系列设计改进措施,优化改进后的应急补水设施可保证严重事故工况下M 310核电机组应急补水设施的可用性,从而进一步提高核电机组的安全性. 相似文献
86.
Computational modeling of cathodic limitations on localized corrosion of wetted SS 316L at room temperature 总被引:1,自引:0,他引:1
The ability of a SS 316L surface wetted with a thin electrolyte layer to serve as an effective cathode for an active localized corrosion site was studied computationally. The dependence of the total net cathodic current, Inet, supplied at the repassivation potential Erp (of the anodic crevice) on relevant physical parameters including water layer thickness (WL), chloride concentration ([Cl−]) and length of cathode (Lc) were investigated using a three-level, full factorial design. The effects of kinetic parameters including the exchange current density (io,c) and Tafel slope (βc) of oxygen reduction, the anodic passive current density (ip) (on the cathodic surface), and Erp were studied as well using three-level full factorial designs of [Cl−] and Lc with a fixed WL of 25 μm. The study found that all the three parameters WL, [Cl−] and Lc as well as the interactions of Lc × WL and Lc × [Cl−] had significant impact on Inet. A five-factor regression equation was obtained which fits the computation results reasonably well, but demonstrated that interactions are more complicated than can be explained with a simple linear model. Significant effects on Inet were found upon varying either io,c, βc, or Erp, whereas ip in the studied range was found to have little impact. It was observed that Inet asymptotically approached maximum values (Imax) when Lc increased to critical minimum values. Imax can be used to determine the stability of coupled localized corrosion and the critical Lc provides important information for experimental design and corrosion protection. 相似文献
87.
WANG Bowen CAO Shuying WENG Ling HUANG Wenmei SUN Ying 《稀有金属(英文版)》2006,25(5):538-542
The structure, magnetization, and magnetostriction of Sm0.9Pr0.1Fex and Sm1-xNdxFel.9 thin films have been investigated using X-ray diffraction, vibrating sample magnetometer, and optical cantilever method. It is found that the structure of Sm0.9Pr0.1Fex thin films consists of an Sm-Pr-Fe amorphous phase when x≤2.69 and that of Sm1-xNdxFel.9 thin films consists of an Sm-Nd-Fe amorphous phase. The in-plane magnetization of Sm0.91Pr0.1Fex thin films increases with increase in the Fe content, and low values of the in-plane coercivity occur in the range of 1.62≤ x≤ 2.28. The magnetostriction value of Sm0.91Pr0.1Fex thin films increases with increasing the Fe content when x ≤ 1.94 and decreases when x 〉 1.94. The in-plane magnetostriction of Sm1-xNdxFe1.9 thin films under low magnetic fields has been improved by the substitution of Nd for Sm when x = 0.2. 相似文献
88.
The main aim of this work was to study the effects of particle size, particle volume fraction, and matrix strength on the
long fatigue crack growth resistance of two different grades of Al alloys (Al2124-T1 and Al6061-T1) reinforced with SiC particles.
Basically, it was found that an increase in particle volume fraction and particle size increases the fatigue crack growth
resistance at near threshold and Paris regimen, with matrix strength having a smaller effect. Near final failure, the stronger
and more brittle composites are affected more by static modes of failure as the applied maximum stress intensity factor (K
max) approaches mode I plane strain fracture toughness (K
IC). 相似文献
89.
由于目前缺乏对浮式取水口前流场变化规律的研究,以分析水库水温分层对取水口前各断面流速分布影响为目标,依据某水库水温资料,采用k-ε紊流模型对浮式取水口前流场进行三维数值模拟,针对水库水温均一和水温分层的两种情况,研究取水口前流速分布,分析水库水温分层对取水口前各断面流速分布的影响。研究结果表明,在浮式取水口附近,水温均一和水温分层的流速分布存在着差异,这种差距随着取水流量和淹没深度的增大而减小。研究成果可为浮式管型取水设施的应用和运行提供技术支持,为取水水温预测提供理论依据。 相似文献
90.
Heavy-oil-in-water (o/w) emulsions containing produced sand were prepared using commercially available emulsifiers. The emulsions were tested in beakers for emulsion type, quality, and sand-retention characteristics. The apparent viscosities of the o/w emulsions were measured. The effects of polymer addition on the apparent viscosity and sand-carrying capability of the emulsions were also studied. The results of the breaker tests indicate that most emulsifier solutions water-wet the beaker wall and temporarily improve heavy-oil flow characteristics. However, most of the chemicals also water-wet the sand particles and cause sand dropout. The Flothin F2 chemical alone showed stable oil dispersion and, in combination with the Flocon 4800C polymer, showed very good sand-retention, viscosity-reduction, and stable oil-dispersion characteristics. 相似文献