Design and Robust Performance Evaluation of a Fractional Order PID Controller Applied to a DC Motor

This paper proposes a methodology for the quantitative robustness evaluation of PID controllers employed in a DC motor. The robustness analysis is performed employing a 2~3 factorial experimental design for a fractional order proportional integral and derivative controller(FOPID), integer order proportional integral and derivative controller(IOPID)and the Skogestad internal model control controller(SIMC). The factors assumed in experiment are the presence of random noise,external disturbances in the system input and variable load. As output variables, the experimental design employs the system step response and the controller action. Practical implementation of FOPID and IOPID controllers uses the MATLAB stateflow toolbox and a NI data acquisition system. Results of the robustness analysis show that the FOPID controller has a better performance and robust stability against the experiment factors.

Individual Word Length Patterns for Fractional Factorial(Split-Plot)Designs

Fractional factorial(FF)designs are commonly used for factorial experiments in many fields.When some prior knowledge has shown that some factors are more likely to be significant than others,Li,et al.(2015)proposed a new pattern,called the individual word length pattern(IWLP),which,defined on a column of the design matrix,measures the aliasing of the effect assigned to this column and effects involving other factors.In this paper,the authors first investigate the relationships between the IWLP and other popular criteria for regular FF designs.As we know,fractional factorial split-plot(FFSP)designs are important both in theory and practice.So another contribution of this paper is extending the IWLP criterion from FF designs to FFSP designs.The authors propose the IWLP of a factor from the whole-plot(WP),or sub-plot(SP),denoted by the I_w WLP and Is WLP respectively,in the FFSP design.The authors further propose combined word length patterns C_(w) WLP and Cs WLP,in order to select good designs for different cases.The new criteria C_(w) WLP and Cs WLP apply to the situations that the potential important factors are in WP or SP,respectively.Some examples are presented to illustrate the selected designs based on the criteria established here.

Construction of Split-Plot Designs with General Minimum Lower Order Confounding

Fractional factorial split-plot design has been widely used in many fields due to its advantage of saving experimental cost. The general minimum lower order confounding criterion is usually used as one of the attractive design criterion for selecting fractional factorial split-plot design. In this paper, we are interested in the theoretical construction methods of the optimal fractional factorial split-plot designs under the general minimum lower order confounding criterion. We present the theoretical construction methods of optimal fractional factorial split-plot designs under general minimum lower order confounding criterion under several conditions.

Bounds on the maximum numbers of clear two-factor interactions for 2^((n1+n2)-(k1+k2)) fractional factorial split-plot designs

Fractional factorial split-plot (FFSP) designs have an important value of investigation for their special structures.There are two types of factors in an FFSP design: the whole-plot (WP) factors and sub-plot (SP) factors,which can form three types of two-factor interactions:WP2fi,WS2fi and SP2fi.This paper considers FFSP designs with resolution Ⅲ or Ⅳ under the clear effects criterion.It derives the upper and lower bounds on the maximum numbers of clear WP2fis and WS2fis for FFSP designs,and gives some methods for constructing the desired FFSP designs.It further examines the performance of the construction methods.

Minimum secondary aberration fractional factorial split-plot designs in terms of consulting designs

It is very powerful for constructing nearly saturated factorial designs to characterize fractional factorial (FF) designs through their consulting designs when the consulting designs are small. Mukerjee and Fang employed the projective geometry theory to find the secondary wordlength pattern of a regular symmetrical fractional factorial split-plot (FFSP) design in terms of its complementary subset, but not in a unified form. In this paper, based on the connection between factorial design theory and coding theory, we obtain some general and unified combinatorial identities that relate the secondary wordlength pattern of a regular symmetrical or mixed-level FFSP design to that of its consulting design. According to these identities, we further establish some general and unified rules for identifying minimum secondary aberration, symmetrical or mixed-level, FFSP designs through their consulting designs.

Theory of optimal blocking for fractional factorial split-plot designs

The issue of optimal blocking for fractional factorial split-plot (FFSP) designs is considered under the two criteria of minimum aberration and maximum estimation capacity. The criteria of minimum secondary aberration (MSA) and maximum secondary estimation capacity (MSEC) are developed for discriminating among rival nonisomorphic blcoked FFSP designs. A general rule for identifying MSA or MSEC blocked FFSP designs through their blocked consulting designs is established.

Connection Among Some Optimal Criteria for Symmetrical Fractional Factorial Designs

为部分因素的图案的一个基本、实际的问题是最佳的因素赋值的问题。最近，一些新标准 WV 标准， NB 标准和一致性标准例如概括最小的错误，为比较并且选择部分被建议。在这篇论文，我们显示这些标准为对称的部分阶乘图案同意相当好。

Optimal Design of Thermal Dissipation for the Array Power LED by using the RSM with Genetic Algorithm

In accordance with the enhancement for luminous efficiency improving, LED (Light Emitting Diode) has been gradually developed by combining the characteristics of small volume, impact resistance, good reliability, long life, low power consumption with multiple purposes for energy saving and environmental protection. Therefore, the array LED has been widely applied in human livings nowadays. This study applies the finite element analysis software ANSYS to analyze the thermal behavior of the array power LED work lamp which is modeled by four same-size LED with MCPCB (Metal Core Print Circuit Board) mounted on a base heat-sink. The Flotran heat flow analysis is applied to obtain the natural convection of air coefficient, while the convection value can be confirmed by the iterative method since it is set as the boundary condition for ANSYS thermal analysis to obtain the temperature distribution, accordingly the chip junction temperature and the base heat-sink temperature were followed through experiments in order to check if the simulation results meet the design requirements and coincide with the power LED product design specification. Prior to the optimal design process for chip junction temperature, the most significant parameters were first chosen by the fractional factorial design. The regressive models were respectively setup by the dual response surface method (RSM) and the mixed response surface method. Furthermore, the genetic algorithm combined with response surface method was applied to acquire the optimal design parameters, and the results were obtained from both methods, which are reviewed for comparison. Afterwards, the mixed response surface method is adopted to investigate the effects of interactions among various factors on chip junction temperature. In conclusion, it is found that the thermal conductivity of MCPCB and the height of base heat-sink are the two major significant factors. In addition, the interactive effects between chip size and thermal conductivity of chip adhesion layer are acknowledged as the most significant interaction influenced on the chip junction temperature.

基于改进响应面的邓肯-张E-B模型参数全局敏感性分析

为研究邓肯-张E-B模型参数及参数之间的交互作用对大坝变形的影响,以某均质黄土坝为研究对象,利用改进的响应面方法分析了邓肯-张E-B模型参数的全局敏感性。通过部分因子设计筛选出对土坝变形影响较为显著的5个参数为R_(f)、γ、φ_(0)、K_(b)、K,再利用响应面方法中的中心复合设计对筛选结果做进一步的全局响应面分析,考察参数及参数之间的交互作用对土坝变形的影响。结果表明,R_(f)、γ、φ_(0)是对大坝位移敏感性最强的3个参数,这3个参数之间的交互作用对于大坝变形的敏感性同样重要,且高于单个因素的敏感性,在类似工程计算中应考虑参数之间的交互作用。

高速铁路梁桥建模参数敏感性分析

平衡模型建立效率和确保模型计算结果的准确性一直以来都是高速铁路梁桥概率地震需求分析所面临的挑战。鉴此,首先,以典型高速铁路简支梁桥和连续梁桥为工程背景,罗列建模相关不确定性参数及其概率分布;其次,采用分式析因设计方法,基于OpenSees建立的有限元模型生成了32组考虑15种建模不确定性参数的计算工况;最后,通过方差分析得到的p值确定不同建模参数对构件地震响应的影响程度,从而筛选出高速铁路梁桥建模时需考虑的重要参数。分析结果表明:不同构件地震响应对建模参数的敏感性差异明显,但地震波加载方向、支座摩擦因数、混凝土密度和结构阻尼比这4个建模参数以及混凝土弹性模量和混凝土抗压强度的交互作用均显著影响2种梁桥的地震响应,在进行高速铁路梁桥概率地震需求分析时不可忽略;简支梁桥和连续梁桥在建模时还应分别关注滑动层初始刚度和桩基础平动刚度的不确定性。在高速铁路梁桥概率地震需求分析中考虑重要建模参数的不确定性,可以在确保构件地震响应预测准确的同时提升建模效率。

合理进行均值比较——析因设计定量资料多元方差分析

本文目的是介绍与析因设计定量资料多元方差分析有关的基本概念、计算方法、两个实例以及SAS实现。基本概念包括交互作用、析因设计、含区组因素的析因设计和分式析因设计;计算方法涉及一般统计量和检验统计量;两个实例分别涉及“制造塑料胶片过程中挤压度和添加剂剂量对其性能的影响”和“寻找挤压塑料胶卷的最优工艺条件”。借助SAS对两个实例中的定量资料进行多元方差分析,并对如何确定最终的方差分析模型进行讨论。

三水平部分因析设计中条件主效应的变量选择

显著效应识别是部分因析设计中一个非常重要的研究内容,但按照传统方法识别出的交互作用项往往很难解释。在传统分析方法的基础上,结合LASSO方法,本文提出一种在三水平部分因析设计中条件主效应的变量选择方法,并将其与传统方法做了分析比较。结果表明,基于LAS-SO回归的条件主效应分析方法得到的模型项数更少,p值更小,拟合程度更高,选取的条件主效应项更容易解释。

Interference Adsorption Mechanisms of Dimethoate, Metalaxyl, Atrazine, Malathion and Prometryn in a Sediment System Containing Coexisting Pesticides/Heavy Metals Based on Fractional Factor Design（Resolution V） Assisted by 2D-QSAR

The mechanisms of adsorption of pesticides（dimethoate, metalaxyl, atrazine, malathion and prometryn） and heavy metals（Cu, Cd, Pb, Zn and Ni） coexisting in sediments, with pesticides as target pollutants, and the influence of their main effects and double-order interaction effects were studied using the experimental design module in the Minitab software package with a 2^10-3 fractional factorial design method at resolution V. The main, double-order interaction, synergistic and antagonistic effect values of pollutant concentrations influencing the adsorption of pesticides were set as dependent variables, while various quantum chemical parameters of pesticides were set as independent variables, and two-dimensional quantitative structure activity relationship（2D-QSAR） models were established by stepwise regression to reveal the adsorption mechanisms of pesticides in a composite contamination system. The main effects of pollutants concentration played the primary role in the adsorption of dimethoate and malathion（the rates of contributions were 53.54% and 56.46%, respectively）, while double-order interaction effects were primarily responsible for metalaxyl, atrazine and prometryn adsorption（the rates of contributions were 79.05%, 60.21% and 57.89%, respectively） in the pesticide/heavy metals coexisting sediment system. The synergistic effects of the main effects and double-order interaction effects of pollutants concentration（synergistic effects） played a leading role in adsorption of malathion and prometryn（the rates of contributions were 70.61% and 69.61%, respectively）, while an- tagonistic effects of the main effects and double-order interaction effects of pollutants（antagonistic effects） played a dominant role in the adsorption of dimethoate, metalaxyl and atrazine（the rates of contributions were 58.82%, 56.89% and 58.24%, respectively）. Moreover, the correlation coefficient value（R2） ranged from 0.986 to 0.999（〉0.8783） in the 2D-QSAR model, while the standard deviation（SD） ranged from 0.006 to 0.066 and the Ftest values were 22.684-199.544, indicating the model has good predictive ability and fit. The 2D-QSAR model revealed a significant correlation（P=0.05） between the main effects of pollutants concentrations on pesticides adsorption（main effect values） and the most positive hydrogen atomic charge（qa＋）, the highest occupied molecular orbital energy（EHOMO） and the dipole moment（μ）. Furthermore, double-order interaction effect values of pollutant concentrations influenced the adsorption of pesticides（double-order interaction effect values）, and the most positive atomic charge（q＋）, qH＋, and the lowest unoccupied molecular orbital energy（ELMO） were significantly correlated. The qw, EHOMO and μ of pesticides were found to be significant factors promoting pesticides adsorption, while the q＋ and ELVMO of pesticides were significant inhibiting factors（P=0,05）. Overall, this study provides a theoretical basis for further realization of combined pollution control of pesticide pollutants in complex environmental systems.

零余子多酚类物质的提取工艺及测定方法比较

本研究主要采用析因试验对零余子多酚类的最佳提取工艺进行了探讨,同时比较了多酚类物质的两种不同测定方法的差异。实验结果发现:采用FC法测定时,零余子多酚的最佳提取工艺为:乙醇浓度为75.3%,乙醇与盐酸比为98.3:1.7,提取温度为82.5℃,料液比1:30,此时多酚得率为11.1615mg/g。采用普鲁士蓝法检测时,最佳提取条件为:乙醇浓度为70%,醇酸比为97.6:2.4,提取温度为96℃,料液比1:30,此时零余子多酚的最高得率为4.4503mg/g。采用不同的测定方法,零余子多酚的最佳提取工艺略有不同,而且最高得率也不同。

中心组合设计优化必特螺旋霉素合成培养基

将克隆自卡波霉素产生菌的4"-O-异戊酰基转移酶基因整合到螺旋霉素产生菌S trep tomy ces sp iramy ceticus F-21的染色体上,构建成一株稳定的生物工程菌W SJ-1-195,它产生的一组以4"-O-异戊酰螺旋霉素为主要成分的多组分基因工程新型抗生素命名为必特螺旋霉素。针对目前没有适合必特螺旋霉素产生菌的合成培养基,所以本文顺序通过部分因子析因设计法、最速上升实验、中心组合实验,并利用统计学软件SA S V 8对实验数据进行分析,确定了必特螺旋霉素合成培养基的组成,为以后对必特螺旋霉素生理生化特性的研究提供基础。经过优化后必特螺旋霉素的发酵效价从173μg/m l提高到1880μg/m l。

一株微生物絮凝剂产生菌的培养基优化研究

利用单因子实验和部分因子实验对实验室保藏的产絮凝剂菌种C3的培养基进行优化,以提高C3菌所产生的微生物絮凝剂MBFC3的絮凝效果。实验结果表明,C3菌产MBFC3的最适培养基为:蔗糖1.0g,(NH4)2SO40.24g,FeSO40.10g,KH2PO40.40g,MgSO40.01g,NaCl0.02g,蒸馏水100mL,pH值自然。在此培养条件下,C3菌所产生的微生物絮凝剂MBFC3对高岭土悬浮液的絮凝率可达到99.1%。实验中还发现,培养基中(NH4)2SO4和NaCl的用量是影响MBFC3絮凝效果的显著因素。

碱性双氧水法预处理木质纤维素

在采用木质纤维素制备燃料乙醇工艺中,纤维素酶对纤维素物质的可及性对纤维素的酶解过程非常重要,木质纤维素物质的预处理过程就是通过溶解木质素、半纤维素以及破坏纤维素的结晶结构,以提高纤维素酶的可及性。采用碱性双氧水法处理木质纤维素,应用部分重复因子设计的实验方法考察了反应时间(tR)、反应温度(Te)、双氧水用量(ch)、液固比(Vr)和NaOH浓度(cb)5个因素对预处理效果的影响,确定tR=18 h、Te=70℃c、h=1%、Vr=8 g.L-1、cb=10 g.L-1为较优化的条件。

液体培养的桑黄胞外多糖发酵培养基成分的优化

通过27-3IV部分因子设计(FFD),对葡萄糖、蛋白胨、酵母膏、磷酸二氢钾、硫酸镁、VB1以及草酸铵7个营养因子进行筛选。在此基础上,采用中心组合设计对部分因子设计,筛选出对桑黄胞外多糖产量的关键因子,确定培养基的组成和水平。在葡萄糖34.12g/L、酵母膏5.01g/L、蛋白胨4g/L、MgSO40.75g/L、KH2PO41g/L、VB10.0075g/L、草酸铵0.88g/L的条件下进行5次平行发酵实验。结果发现桑黄胞外多糖平均产量为(2.363±0.04)g/L,与预测值(2.342g/L)基本相符。可见,用该回归模型优化产桑黄胞外多糖的发酵培养基是可行的。

产弹性蛋白酶EL314CF10菌株种子培养基优化的研究初报

采用两水平部分因子实验设计 (FFD)研究了产弹性蛋白酶菌株的种子培养基各组分对菌体生长的影响 ,并找出主要影响因子为牛肉膏、酵母膏 ,二者都在 99%的概率水平上对菌体生长有正效应。而蛋白胨对菌体生长影响是负效应 ,但不显著。NaCl对菌体生长影响也极不显著。由方差分析结果可知 ,选取的水平接近最大响应区域。因此不再进行最陡爬坡实验。最后用中心复合设计及响应面分析确定主要影响因子的最佳浓度。由实验结果可知 ,菌株在优化后的种子培养基中生物量比未优化培养基高。