Hybrid surrogate-model-based multi-fidelity efficient global optimization applied to helicopter blade design

A multi-fidelity optimization technique by an efficient global optimization process using a hybrid surrogate model is investigated for solving real-world design problems. The model constructs the local deviation using the kriging method and the global model using a radial basis function. The expected improvement is computed to decide additional samples that can improve the model. The approach was first investigated by solving mathematical test problems. The results were compared with optimization results from an ordinary kriging method and a co-kriging method, and the proposed method produced the best solution. The proposed method was also applied to aerodynamic design optimization of helicopter blades to obtain the maximum blade efficiency. The optimal shape obtained by the proposed method achieved performance almost equivalent to that obtained using the high-fidelity, evaluation-based single-fidelity optimization. Comparing all three methods, the proposed method required the lowest total number of high-fidelity evaluation runs to obtain a converged solution.     

Crashworthiness optimization of honeycomb structures under out-of-plane impact using radial basis functions

Crashworthiness design and development of lightweight structures have become important engineering challenges because of the high standards of energy consumption and safety regulations. Within this context, the use of honeycomb structures as crush absorber is continuously growing in automotive and aircraft industries, once honeycombs are known for their high strength-to-weight ratio and excellent energy absorbing capacity. Thus, this paper presents a method that combines radial basis functions with expected improvement to optimize the specific energy absorption of honeycomb cellular materials, while the peak crush force is constrained at low levels for safety reasons. Honeycomb's cell size, cell shape and thickness are the design variables. Concerning the cell shape, the results indicate the hexagonal configuration has a higher out-of-plane performance compared to auxetic and rectangular cells in terms of energy absorption capacity. Lastly, a multi-objective optimization using only the radial basis function predictor (without sequential sampling) is carried out to seek simultaneously for optimal solutions with minimum peak force and maximum specific energy absorption.     

Conditional mean- and median-based cumulative sum control charts for Weibull data

This article deals with the monitoring of censored data using the cumulative sum (CUSUM) control charts for Weibull lifetimes under type-I censoring. To develop an efficient CUSUM structure for censored data, we use the conditional expected value (CEV) and conditional median (CM) approaches. In particular, we focus on the detection of shifts in the mean of Weibull lifetimes assuming censored data. In addition to fixed/known parameter values, the effect of estimation is assessed on the detection power of control charts. The performance of the proposed charts is evaluated by the average run length (ARL). Furthermore, the ARL performance of CUSUM charts is compared with CEV- and CM-based exponentially weighted moving average (EWMA) control charts. Besides an extensive simulation study, the significance of the current work is illustrated by a data set on the response time of a thermostat experiment.     

基于免疫蜂群算法的冷轧生产调度优化方法

冷轧生产调度是一个复杂的约束组合优化问题,生产约束包括轧制板坯的宽度、厚度、硬度跳变及交货期提前和拖后惩罚等。基于1．sP（多旅行商）问题,建立了冷轧生产调度问题的最小值模型,提出了一种免疫蜂群优化求解算法。通过给蜂群注射疫苗产生出代表新的解集的种群,避免算法在优化过程中陷于局部极值。针对工业数据的仿真结果表明：免疫蜂群优化算法明显优于人工蜂群优化算法的解,具有较好的收敛性和快速性。     

基于收益法评估企业价值的评估指标性质及选择

在企业价值评估中,企业未来收益额、收益期及折现率是关键指标。在对各项指标的性质进行分析的基础上,重点运用GM（1,1）模型对企业未来收益额的预测进行探讨,同时对折现率的测算方法进行对比分析,并指出各项评估指标确定方法的合理选择。     

我国城镇居民可支配收入与消费支出的灰色关联分析

应用灰色关联分析方法,研究了1990年～2004年和2006年～2009年两个阶段我国城镇居民消费支出与可支配收入之间的关系.根据灰色分析显示,在1990年～2004年间,与人均可支配收入变化曲线的几何形状相似程度较高的消费支出项目依次为衣着类、家庭设备、用品及服务类和食品类,杂项商品与服务类排第5位,居住类位居第6位...     

一种优化型电网故障诊断的实用改进模型

基于保护和断路器状态信息的优化型故障诊断,是目前为止为数不多的已有实际应用的诊断方法.对经典的优化型故障诊断模型进行了深入分析,找出了其中的不足.然后在只基于保护和断路器状态信息的情况下,提出了在保证不漏判的前提下尽量减少误判的诊断原则.通过对现有模型和断路器期望表达式的改进,达到了这一目标,解决了原有模型在警报信息丢...     

城市低保制度目标定位过程中的家计调查及方法改进

城市低保制度目标定位过程中家计调查方法对提高制度目标定位效率发挥了巨大作用,但尚需进一步改进与调整。文章从目标定位及家计调查的理论基础出发,论述了现行城市低保制度的家计调查方法的应用及存在的主要问题,最后提出改进家计调查方法并进一步提高城市低保制度目标定位效率的对策。     

长吉图开发战略对吉林省居民收入提高的促进作用探析

结合近年我省经济发展与城乡居民收入发展变化情况,就长吉图开发战略的社会福利效果展开探讨。认为实施长吉图开发战略在推动吉林省经济全面振兴的同时,也将在提高城乡居民收入方面产生巨大的促进作用。     

基于居民收入分配的个人所得税改进探讨

分析了我国城乡居民收入差距、不同行业居民收入差距、不同地区居民收入差距的现状;提出了建立纳税人税号制,以家庭为单位结合人口、地区平均消费水平、物价指数实行动态扣除后缴纳个人所得税的税改建议。