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1.
首先利用了动态特性的响应曲面方法对某热膨胀仪进行了稳健实验设计;然后把得到的优化结果与利用田口的SN比方法得到的优化结果进行了比较,结果表明响应曲面方法较SN比方法有很多优良性质,是对田玄一博士的SN比方法的一种有效改进途径。  相似文献   

2.
研究动态质量特性优化问题,考虑多响应的最优性和稳健性,提出用神经网络建模、双响应曲面法和满意度函数法相结合的方法解决动态质量特性与信号因子之间存在非线性相关关系的多响应稳健参数设计问题.先将噪声因子的变化看作对响应的重复影响,利用神经网络和双响应曲面建立信号因子、可控因子与位置、散度之间的复杂模型;再运用指数满意度函数将多个双响应曲面值转化为单一的满意度衡量指标,利用遗传算法全局寻优得到最佳可控因子设置;最后利用获得的最佳可控因子组合得到信号因子与多响应之间的数据对,进而得到反映信号因子与响应之间真实关系的具体模型.  相似文献   

3.
为了持续提高实验教学的质量,优化测量系统的性能,从质量管理的角度出发,提出了把实验设备纳入测量系统的范畴,探索最优工作点的方法。根据响应曲面方法的原理,分析实验教学测量系统的影响因素,建立测量模型,搜集样本和采集测量数据,分析测量数据的统计特性,从曲面空间中寻找最优工作点,在实际测量中检验最优工作参数,从而获得优化测量系统性能的方案;在模拟信号系统的噪声实验教学测量系统性能的优化中,应用响应曲面法使实验室测量的通过率提高10%。这表明,响应曲面方法在高校实验教学设备的性能优化中是一种有实用价值的方法。  相似文献   

4.
针对复杂结构仿真中有限元仿真精度及效率不高的问题,提出采用高阶响应面方法进行建模及优化,并用桥梁模型来验证。选取合适参数,采用试验设计获取响应样本点,基于数理统计的逐步回归法对各自变量进行显著性分析,筛选对目标响应函数显著度高的自变量,再应用最小二乘法拟合各自变量的系数,得到三阶多项式响应面模型,用多目标优化算法进行优化。对比修正前后模态频率,结果表明应用响应面方法能得到简单而高精度的结构模型,从而验证了高阶响应面方法在建模及模型优化中的有效性。  相似文献   

5.
文章利用优化方法给出了刚性运动中两个二次曲面的拼接光滑程度的一种新定义,它是介于C-0连续和C-1连续之间的,并指出曲面在何处可以达到C-1连续,此方法适用于一些自由曲面的设计。  相似文献   

6.
以山茱萸为主要原料,确定了微波辅助萃取山茱萸多糖的最佳工艺条件.采用响应曲面优化试验方法,以山茱萸多糖的提取率为响应值,物料比、微波时间、微波功率为因素.最终得到最佳工艺条件为:物料比0.05(1:19),微波功率541.17 W,微波处理时间8.87 min.在该条件下,多糖提取率为12.34%±0.50.  相似文献   

7.
以合肥雨水泵站外排雨水为研究对象,利用磁絮凝技术对其进行快速处理,实验采取响应曲面优化实验方法对实验数据进行优化,以COD、TP浓度为主要参考指标,采用Box-Behnken模型对数据进行分析,得出絮凝剂聚合氯化铝(PAC)、助凝剂聚丙烯酰胺(PAM)及磁粉的最佳投药量及投加顺序.通过实验研究及经济性分析,为磁絮凝应用于实际工程治理提供了依据.  相似文献   

8.
利用基于密度泛函理论的赝势平面波方法对CdS晶体的结构进行了几何优化,在优化的基础上对弹性常数与热力学性质进行了系统地计算.计算结果得到弹性常量C11=82.39GPa、C12=66.68GPa、C44=23.62GPa;零温度与零压下的德拜温度为204.9K;运用线性响应方法确定了声子色散关系,并得到CdS的等容比热容、焓、自由能、熵等热力学函数随温度变化的关系.科用基于密度泛函理论的赝势平面波方法对CdS晶体的结构进行了几何优化,在优化的基础上对弹性常数与热力学性质进行了系统地计算.计算结果得到弹性常量;零温度与零压下的德拜温度为204.9K;运用线性响应方法确定了声子色散关系,并得到CdS的等容比热容、烩、自由能、熵等热力学函数随温度变化的关系.  相似文献   

9.
目的:1.比较并改善翼型参数化方法,获得设计变量少、拟合精度高的参数化方法;2.在参数化的基础上利用数值模拟的方法获取翼型流场参数,优化并获得特定条件下升阻比最大的翼型。创新点:1.通过与多项式拟合方法的对比证明了类别/形状函数转换(CST)法在翼型拟合方面的优越性,并通过调整控制点分布,在不增加设计变量的基础上改善了CST方法;2.通过建立响应面模型,利用多岛遗传算法与非线性序列二次规划法相结合的方式获得了更好的翼型优化效果。方法:1.利用修饰后的CST法对翼型进行参数化拟合与设计,并通过与二项式拟合法比较来验证其优越性;2.通过数值方法对翼型周围流场进行计算并与实验结果对比,获得精确计算气动参数的仿真条件;3.通过拉丁超立方采样获得设计变量,建立设计变量与翼型升阻比之间的响应面模型,通过多岛遗传算法与非线性序列二次规划法的结合和优化,得到一定条件下升阻比最大的翼型。结论:1.CST法是一种优秀的参数化方法,本文的优化改善了形状函数控制点选取法则,使其对翼型头部和尾部的描述更加精确;与多项式相比,CST法可以通过更少的设计变量得到更高的拟合精度。2.基于多岛遗传算法的非线性序列二次规划法在本文中用以优化翼型使其具有更高升阻比。优化前后翼型的比较显示,两种优化方法的结合可以得到比单独使用各优化方法更好的结果。  相似文献   

10.
对模具自由曲面数控加工工艺的规划方法进行研究,建立了适于模具自由曲面数控加工的工艺规划。针对某模具的自由曲面,根据工艺规划得到的自由曲面加工工艺参数,在UG NX 8.0中设定各项参数,生成刀具加工路径,进行仿真加工,获得其数控加工代码。实例加工证明,该规划方法使模具加工工艺信息得到了最大程度地有效利用,降低了模具设计的工作量,提高了生产效率,降低了设计成本。  相似文献   

11.
响应面法优化兰香草总黄酮超声提取工艺   总被引:1,自引:0,他引:1  
采用NaNO2-Al(NO3)3-NaOH体系分光光度法,测定吸光度,比较不同条件下兰香草总黄酮提取率;在单因素试验的基础上利用响应面法对提取工艺进行优化设计;通过Plackett-Burman软件对试验因素进行筛选;应用Design Expert 7.0软件对试验因素进行中心组合设计,并将实验结果进行回归分析。结果表明,乙醇浓度、液料比、提取时间为影响兰香草总黄酮提取率的主要因素;试验所得模型与试验数据拟合度较高,可用来预测不同提取条件下的兰香草总黄酮得率;由回归方程求得的最佳提取工艺为在40℃温度下,用73%乙醇为溶剂,控制液料比为45 mL·g-1,提取32 min。  相似文献   

12.
Biotransformation of phytosterol(PS) by a newly isolated mutant Mycobacterium neoaurum ZJUVN-08 to produce androstenedione has been investigated in this paper.The parameters of the biotransformation process were optimized using fractional factorial design and response surface methodology.Androstenedione was the sole product in the fermentation broth catalyzed by the mutant M.neoaurum ZJUVN-08 strain.Results showed that molar ratio of hydroxypropyl-β-cyclodextrin(HP-β-CD) to PS and substrate concentrations were the two most significant factors affecting androstenedione production.By analyzing the statistical model of three-dimensional surface plot,the optimal process conditions were observed at 0.1 g/L inducer,pH 7.0,molar ratio of HP-β-CD to PS 1.92:1,8.98 g/L PS,and at 120 h of incubation time.Under these conditions,the maximum androstenedione yield was 5.96 g/L and nearly the same with the non-optimized(5.99 g/L),while the maximum PS conversion rate was 94.69% which increased by 10.66% compared with the non-optimized(84.03%).The predicted optimum conditions from the mathematical model were in agreement with the verification experimental results.It is considered that response surface methodology was a powerful and efficient method to optimize the parameters of PS biotransformation process.  相似文献   

13.
An excellent airfoil with a high lift-to-drag ratio may decrease oil consumption and enhance the voyage. Based on NACA 0012, an improved airfoil is explored in this paper. The class/shape function transformation has been proved to be a good method for airfoil parameterization, and in this paper it is modified to improve imitation accuracy. The computational fluid dynamics method is applied to obtain numerically the aerodynamic parameters of the parameterized airfoil, and the result is proved credible by comparison with available experimental data in the open literature. A polynomial-based response surface model and the uniform Latin hypercube sampling method are employed to decrease computational cost. Finally, the nonlinear programming by quadratic Lagrangian method is utilized to modify the multi-island genetic algorithm, which has an improved optimization effect than the method used on its own. The obtained result shows that the modified class/shape function transformation method produces a better imitation of an airfoil in the nose and tail regions than the original method, and that it will satisfy the tolerance zone of the model in a wind tunnel. The response surface model based on the uniform Latin hypercube sampling method gives an accurate prediction of the lift-to-drag ratio with changes in the design variables. The numerical result of the flow around the airfoil shows reasonable agreement with the experimental data graphically and quantitatively. Ultimately, an airfoil with better capacity than the original one is acquired using the multi-island genetic algorithm based nonlinear programming by quadratic Lagrangian optimization method. The pressure contours and lift-to-drag ratio along with the attack angle have been compared with those of the original airfoil, and the results demonstrate the strength of the optimized airfoil. The process for exploring an improved airfoil through parameterization to optimization is worth referencing in future work.  相似文献   

14.
讨论了正项级数的两种判别法:比值判别法和根值判别法,以及两者的关系,从一个引理出发证明了凡是可用比值判别法的正项级数必能用根值判别法,在一定条件下逆命题也成立。  相似文献   

15.
研究影响白及多糖提取的因素,优化其提取工艺及探究其抑菌活性。通过单因素和响应曲面法,选择提取次数、水提时间、水提温度、液料比4个因素筛选白及多糖的最佳水提工艺,蒽酮-硫酸法测定白及多糖的含量,滤纸片-抑菌圈法测定白及多糖对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌及黑曲霉菌的抑菌作用。经由以上实验设计可得白及多糖最佳提取工艺为:提取次数1次、水提时间2.2 h、水提温度77℃、液料比39.27 mL/g,白及多糖得率31.09%;白及多糖对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌及黑曲霉菌均有抑制作用。  相似文献   

16.
INTRODUCTION It is well known that micro-tremor observation is one of the most convenient methods for investi- gating the dynamic characteristics of the surface ground and the affected structure (Bard, 1998; Dow- rick, 1997). Micro-tremor is a kind of geophysics information related to soil formation of site, corre- sponding to engineering geological condition. The frequency characteristics of micro-tremor can be obtained by spectral analyses of its signals, which can be used to probe into…  相似文献   

17.
密集建筑物下首采区条带充填开采方法研究   总被引:1,自引:0,他引:1  
根据密集群建筑物下首采区煤层赋存的特点,确定采用条带开采采煤方法,同时,采用概率积分法,研究了不同回采率和采煤方法对地表移动特征的影响,采用超高水材料充填开采回收条带煤柱的方法,提高了煤炭资源回采率,为其它类似矿井提供借鉴。  相似文献   

18.
为精准确定灌注桩的沉降,将桩周土体参数看作随机变量,并采用响应面法对桩基可靠度进行研究。由于,与桩沉降相关的多个土体参数之间高阶项可能存在高度相关性,基于高阶正交原理提出了新型非相关响应面法,以克服传统响应面法不考虑高阶参数高阶相关性的难题。结合实际工程计算发现,提出的新型响应面法比传统响应面法得到的值更为保守。可见,如果不考虑参数的高阶相关性,可能导致高估的计算结果。  相似文献   

19.
Although it is assumed that semantics is a critical component of visual word recognition, there is still much that we do not understand. One recent way of studying semantic processing has been in terms of semantic neighbourhood (SN) density, and this research has shown that semantic neighbours facilitate lexical decisions. However, it is not clear if this facilitation reflects actual word recognition processes or is instead due to participant strategies used during the lexical decision task. To address this, the current research used college students as participants and tested the effect of SN density using the semantic categorisation and progressive demasking tasks. Both of these tasks require word identification and are not susceptible to the participant strategies that are seen when using the lexical decision task. The results show that SN facilitates responding in both tasks, indicating that SN effects are not due to task‐specific strategies.  相似文献   

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