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1.
Selahaddin Batuhan Akben 《International journal for numerical methods in engineering》2020,121(24):5590-5599
In this study, a novel multi-objective optimization method based on the best effect of unique input (independent variable) values on responses (dependent variables) was proposed. The proposed method was compared with optimization using Derringer & Suich function that is still the most used. The comparison was made using the response values measured in real experiments and available in the literature. The advantages of the proposed method such as not needing the polynomial model aiming to predict the response values, no parameter selection problem, being able to offer optimum range instead of single optimum value, being suitable for use with existing experimental designs and being simple and interpretable were demonstrated as a result of comparison. It was also suggested how the proposed method will be effective according to experimental designs, and application for the users' application was presented. 相似文献
2.
为解决多目标优化问题,对经典的蚁狮算法进行改进,提出了基于差分进化的准对立学习多目标蚁狮算法(DEQOMALO)。该算法针对蚁狮算法易陷入局部最优的不足,一方面,该算法引用差分进化的思想,充分利用种群和精英蚁狮的信息对原算法中蚂蚁个体的位置更新方式进行改进;另一方面采用反向学习策略对蚂蚁种群进行优化,将原种群个体和其准对立个体进行混合并择优作为新的种群,大大增加种群的多样性。选取典型的标准测试函数,将提出的算法与原始蚁狮算法以及其他传统进化策略优化的蚁狮算法进行比较。实验结果表明,改进算法在收敛性和分布性上均有很大程度的提升,在解决双目标优化问题上具有较好的鲁棒性和有效性。 相似文献
3.
Alternative selection in new product development (NPD) is a multi-criteria decision-making (MCDM) problem. It usually starts with incomplete, imprecise or even partially missing information. Currently, most existing methods in dealing with this problem cannot work well if required information is incomplete or missing. It is acknowledged that stochastic multi-objective acceptability analysis (SMAA) can be applied to address MCDM problem with incomplete preference information and uncertain criteria measurements. In SMAA, alternatives are evaluated based on SMAA measurements (acceptability index, central weight vector and confidence factor). The discriminability of SMAA for the optimum alternative heavily depends on differences of SMAA measurements among different alternatives. Usually, a large number of alternatives and high level of uncertainty are involved in alternative selection in NPD. In this situation, the differences among SMAA measurements are not obvious, and therefore SMAA cannot deal with such problem very well. To this end, this paper proposes an improved SMAA method called Iterative-SMAA (I-SMAA) for alternative selection in NPD. In the I-SMAA, an iterative multi-step decision-making process is suggested to improve differences of SMAA measurements among different alternatives, and thus assist decision makers (DMs) to positively discern from the most preferred alternative. To enhance the decision-making efficiency, sensitive criteria are acquired in each iteration by ranking sensitivity analysis. DMs are guided to provide partial preference information and give more accurate criteria measurements for sensitive criteria rather than all criteria. Eventually, to verify the proposed method, a numerical example of the existing literature is solved with the method, and the results are compared. And then, a practical example of a preparation equipment for coal samples is further employed to verify the practicability of the proposed I-SMAA. 相似文献
4.
Pei LI Guotian CAI Yuntao ZHANG Shangjun KE Peng WANG Liping GAO 《Frontiers in Energy》2020,14(2):241
To improve the overall efficiency of the energy system, the basic structure for the energy internet of coordination and optimization of “generation-grid-load-storage” of Huangpu District, Guangzhou, China is designed, while the arrangement for the output of centralized and distributed energy module and energy storage are proposed. Taking economic benefit maximization, environmental benefit maximization and energy efficiency maximization as sub-objectives, the mathematical model of multi-objective optimal allocation and operation strategy of the energy internet is established considering supply-demand balance constraints, equipment characteristic constraints, operation mode constraints, and energy conditions constraints. The calculation results show that without considering the outsourced electricity, the balanced strategy, the economic development strategy, the environmental protection strategy, and the energy efficiency strategy are obtained by calculation, which are all superior to the traditional energy supply strategy. Moreover, considering the outsourced electricity, the proportion of outsourced electricity to total electricity is 19.8%, which is the system optimization of the energy internet under certain power demand. Compared with other strategies without outsourced electricity, the outsourced electricity strategy can have a certain emission reduction effect, but at the same time reduce the economic benefit. Furthermore, the huge difference in demand for thermal and cooling load between industrial and commercial areas results in the installed capacity of gas distributed energy stations in industrial areas being nearly twice as large as that in commercial areas. The distributed photovoltaic power generation is allocated according to the proportion of the installed roof areas of photovoltaic power generation system in residential, industrial, and commercial areas. 相似文献
5.
为了提升聚合物红外菲涅尔透镜的光学性能,以其表面微沟槽的成型质量为目标,提出了一种高效的注射超声辅助成型方法,并对工艺参数进行了综合质量优化。首先分析了超声振动对聚合物的加热和加压效应,设计了一套一模两腔的对比试验模具;接着以红外菲涅尔透镜的调制传递函数MTF和齿形平均高度h为优化质量目标,设计了四步骤的多目标优化流程,通过试验设计、基于BP神经网络的质量目标与注射工艺参数关系建模、基于NSGA-Ⅱ的多目标优化和试验验证进行工艺参数的综合优化。实验结果表明:该多目标优化流程具有很高的精度,MTF和h的平均预测误差MPE分别为4.16%和3.32%;注射超声辅助成型的菲涅尔透镜微沟槽具有更高的复制质量,其齿沟槽平均高度h增加了15.6%,且h值的波动量随着h值的增大而增大,MTF值受齿高h均匀性的影响大于齿高h对其的影响。 相似文献
6.
7.
针对管道布局、最大允许能耗给定条件下快速热循环注塑成形(RHCM)注塑模具型腔表面快速均匀加热的问题,提出以单根加热棒热流密度为设计变量,以模具型腔表面升温效率和温度分布均匀性为目标,结合有限元模拟、响应面设计以及多目标粒子群优化技术来优化RHCM模具电加热系统。与优化前相比,加热系统优化后,模具型腔表面最大温差降低63.4%,加热系统总能耗降低9%。对比了不同注塑成形工艺条件下成形的平板塑件表面质量,结果表明,相对传统注塑成形(CIM)工艺,RHCM工艺将制品表面粗糙度Ra从320 nm降低到118 nm,并有效抑制了制品表面熔接痕、缩痕等缺陷;发现制品表面粗糙度与型腔表面对应点温度成负相关,说明优化后的型腔表面温度分布更有利于提升制品表面质量。 相似文献
8.
以鄂北水资源配置工程为对象,研究大型调水工程背景下的多水源多目标优化配置。将鄂北地区水库分为充蓄水库、补偿水库与在线水库等3类,根据各类水库特点对鄂北水资源配置工程进行系统概化,建立以年缺水量最小和调水成本最低为目标函数的多水源多目标优化配置模型。采用权重系数法进行求解得到非劣解集。最后采用基于区间犹豫模糊语言与TOPSIS的多目标决策方法对各方案的缺水量与调水量作出评价并遴选出最优方案。研究结果表明:对鄂北水资源配置工程而言,缺水量与调水量的权重比为7∶3的方案综合评价最优,重视缺水的同时兼顾调水成本;基于区间犹豫模糊语言集与TOPSIS的水资源多目标决策方法经本文实例验证具有较高的稳定性与可行性。 相似文献
9.
在过去几十年里,许多多目标进化算法被广泛应用于解决多目标优化问题,其中一种比较流行的多目标进化算法是基于分解的多目标进化算法(MOEA/D)。花朵授粉算法是一种启发式优化算法,但迄今为止,花朵授粉算法在基于分解的多目标进化算法领域的研究还非常少。本文在基于分解的多目标进化算法的框架下,将花朵授粉算法拓展至多目标优化领域,提出一种基于分解的多目标花朵授粉算法(MOFPA/D)。此外,为了保证非支配解的多样性,本文提出一种基于网格的目标空间分割法,该方法从找到的Pareto最优解集中筛选出一定数量且分布均匀的Pareto最优解。实验结果表明,基于分解的多目标花朵授粉算法在收敛性与多样性方面均优于基于分解的多目标进化算法。 相似文献
10.
针对多目标绿色柔性作业车间调度问题(MGFJSP)的特点,提出从碳排放量、噪声和废弃物这3个指标来综合评定环境污染程度,建立了以最小化最大完成时间和环境污染程度为优化目标的MGFJSP模型,并提出了一种改进的人工蜂群算法来求解该模型。算法的具体改进包括:设计了一种三维向量的编码和对应解码方案,在跟随蜂搜索阶段引入一种有效的动态邻域搜索操作来提高算法的局部搜索能力,在侦查蜂阶段提出产生新食物源的策略用于增加种群的多样性。最后进行了实验研究与算法对比,以验证所建模型和所提算法的有效性。 相似文献