电压无功功率优化控制中不可行问题的研究

分析了电力系统电压无功实时优化控制中出现的不可行问题,通过引入模糊约束,从一个新的角度对不可行问题进行了处理,最终获得尽量靠近原不等式约束空间的解。中结合原对偶内点法的特点提出了不可行问题的探测和中结合原对偶内点法的特点提出了不可行问题的探测和处理方法,并用模型系统和华东电力系统的实际数据进行了验算。结果表明,中所提的方法可以有效地探测和处理优化过程中的不可行问题,快速获得合理解。     

参数化图形管理系统

目的讨论参数化图形管理系统ＰＤＭＳ（ＰａｒａｍｅｔｒｉｃＤｒａｗｉｎｇＭａｎａｇｅｍｅｎｔＳｙｓｔｅｍ）的原理和关键技术．方法本系统采用交互式绘制草图方式定义零件原型图,对原型图进行参数化处理,从参数图中可以生成不同尺寸参数值的零件图．结果本系统不仅可以建立参数化标准件库,而且可用于建立复杂结构的参数化非标准件库．结论本系统运行良好,具有很强的实用性     

二次规划问题的降维算法

对等式约束二次规划问题的线性方程组算法进行了研究。从一般等式约束问题的最优性条件出发,构造一个线性方程组,解此方程组便可求得二次规划问题的最优解。     

双金属翅片管蒸汽加热器优化设计软件的开发与应用

提出了以风侧流阻最小为目标函数, 传热负荷与迎风面尺寸为约束条件的双金属翅片管换热器优化设计模型, 并开发出了相应的设计软件,成功地进行了在尿素大颗粒工程中五台蒸汽加热器的优化设计。     

等式约束二次规划问题的降维算法

文献（１）给出了解等式约束问题的一个方法,它比经典的Ｌａｇｒａｎｇｅ乘子算法所解方程组有更低的维数。本文在（１）的基础上,对非线性等式约束进行了线性逼近,从而构造了近似算法,该法在计算上减少了很多的数值困难。     

An experiment on elastically compressed frusta

It is postulated that pre-buckling elastic stress pattern in axially compressed right frustum will determine its initial and progressive buckling mode. The elastic stress profiles along the generator and around various diameters of aluminium alloy frustum under axial compression were measured under different boundary constraints. The shape of such profiles was found to be periodic and wavy with relatively high peaks and high stress gradients at a number of points. It is thought that these peaks correspond to the number of lobes in multi-lobe collapse modes, which are observed when the axial loading exceeds the elastic range. These peaks are attributed to all possible imperfections in geometry and dimensions such as variations in thickness, symmetry, generator length and deviation of the axis from being perpendicular to the cross-section.     

Formal Reduction of Interfaces to Large-scale Process Control Systems

A formal methodology is proposed to reduce the amount of information displayed to remote human operators at interfaces to large-scale process control plants of a certain type.The reduction proceeds in two stages.In the first stage,minimal reduced subsets of components,which give full information about the state of the whole system,are generated by determining functional dependencies between components.This is achieved by using a temporal logic proof obligation to check whether the state of all components can be inferred from the state of components in a subset in specified situations that the human operator needs to detect,with respect to a finite state machine model of the system and other human operator behavior.Generation of reduced subsets is automated with the help of a temporal logic model checker.The second stage determines the interconnections between components to be displayed in the reduced system so that the natural overall graphical structure of the system is maintained.A formal definition of an aesthetic for the required subgraph of a graph representation of the full system,containing the reduced subset of components,is given for this purpose. The methodology is demonstrated by a case study.     

甘肃省陇东地区极端降水的时空特征

为阐明甘肃省陇东地区极端降水的变化规律,利用该地区13个气象台站1961~2015年的逐日降水资料,应用超门限峰值法、反距离加权法、线性倾向估计法、滑动平均法、Mann-Kendall突变分析法、复值Morlet小波分析法研究极端降水的时空变化特征。结果表明,陇东地区各站第95百分位极端降水阈值在27.8mm附近变化,即可以大雨事件作为极端降水事件进行监测;极端降水指数主要表现为从南向北递减的趋势,极端降水事件对环县和崆峒的影响较小;极端降水事件虽然在总量、强度上表现为减小趋势,但其发生频次及对总降水的贡献率逐渐增强;极端降水总量和极端降水强度周期变化均在21年左右能量最强,而极端降水频次和极端降水贡献率周期变化分别在28、5年左右能量最强。     

Risk-involved stochastic performance of hydrogen storage based intelligent parking lots of electric vehicles using downside risk constraints method

Today, the utilizations of hydrogen storage systems (HSS), renewable generation units (PV and wind generation) and distributed energy units are increased in the intelligent parking lots (IPL) in order to charge the electric vehicles (EVs) with clean energy sources. In this work, the uncertainties of upstream grid price, the demand of IPL, wind speed, solar irradiation and temperature are modeled via scenario approach based on stochastic programing. Furthermore, the downside risk constraints method (DRCM) is applied to consider risk related to uncertainties to get risk-involved stochastic performance of hydrogen storage based intelligent parking lots of electric vehicles. The proposed risk-based formulation is modeled using mixed-integer linear programming (MIP) which is implemented under GAMS software and solved via CPLEX solver. Two cases namely risk-averse and risk-neutral strategies are studied and compared to show the effects of DRCM implementation. The obtained results demonstrate the expected performance cost (EPC) of IPL is slowly raised while risk-in-cost (RIC) is significantly reduced due to model of risk related to uncertainties.