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Influence of Chemical Composition on Phase Transformation Temperature and Thermal Expansion Coefficient of Hot Work Die Steel

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Journal of Iron and Steel Research International 2008年第6期15卷 56-61页

作者： XIE Hao-jie WU Xiao-chun MIN Yong-an School of Material Science and Engineering Shanghai University Shanghai 200072 China

On the basis of the uniform design method, six kinds of martensitic hot work die steels were designed. The phase transformation temperatures including Ac1 , Ac3 , and Ms were measured by DIL805A quenching dilatometer. The influences of the main elements on phase transformation temperatures were analyzed by quadratic stepwise regression analysis, and three corresponding equations were obtained. These equations, in which the interactions of the elements were considered, showed more effectiveness than the traditional ones. In addition, the thermal expansion coefficients of these steels in annealed state and quenched state were also obtained during the tests. The influences of chemical composition and temperature on the thermal expansion coefficient were analyzed; the equations obtained were verified by using several kinds of steels. The predicted values were in accordance with the results of the experiments.

关键词： phase transformation temperature thermal expansion coefficient hot work die steel uniform design quadratic stepwise regression analysis

A CASE STUDY IN THE APPLICATION OF SUPERSATURATED designS TO COMPUTER EXPERIMENTS

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Acta Mathematica Scientia 2006年第4期26卷 595-602页

作者：刘民千方开泰 Department of Statistics School of Mathematical Sciences and LPMC Nankai University Tianjin 300071China Department of Mathematics Hong Kong Baptist University Hong KongChina

Supersaturated design is essentially a fractional factorial design in which the number of potential effects is greater than the number of runs. In this article, the supersaturated design is applied to a computer experiment through an example of steady current circuit model problem. A uniform mixed-level supersaturated design and the centered quadratic regression model are used. This example shows that supersaturated design and quadratic regression modeling method are very effective for screening effects and building the predictor. They are not only useful in computer experiments but also in industrial and other scientific experiments.

关键词： Supersaturated design computer experiment uniform design quadratic regression model

NEW LOWER BOUNDS FOR LEE DISCREPANCY ON TWO AND THREE MIXED LEVELS FACTORIALS

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Acta Mathematica Scientia 2016年第6期36卷 1832-1840页

作者：宋硕张琼慧邹娜覃红 College of Science Wuhan University of Science and Technology Wuhan 430065 China Faculty of Mathematics and Statistics Central China Normal University Wuhan 430079 China School of Statistics and Mathematics Zhongnan University of Economics and Law Wuhan 430073 China

The objective of this paper is to study the issue of uniformity on asymmetrical designs with two and three mixed levels in terms of Lee discrepancy. Based on the known formulation, we present a new lower bound of Lee discrepancy of fractional factorial designs with two and three mixed levels. Our new lower bound is sharper and more valid than other existing lower bounds in literature, which is a useful complement to the lower bound theory of discrepancies.

关键词： U-type design Lee discrepancy uniform design lower bound

Optimization of Fermentation Medium for Epothilones Production with Sequential Statistical Approach

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Chemical Research in Chinese Universities 2010年第1期26卷 86-91页

作者： MENG Fan-xin LI You-xin GUO Wei-liang LU Jia-hui DU Lin-na TENG Li-rong College of Life Science Jilin University Changchun 130012 P. R. China

A sequential statistical approach was applied to optimizing the fermentation medium of epothilones（Epos） production by means of a mutant which was obtained by treating polyangium cellulosum ATCC 15384 with nitrite and ultraviolet. The effects of different carbon sources and nitrogen sources on the fermentation medium were tested, and the suitable ones were selected. Then a uniform design was employed to design the experiments. A linear model was developed for identifying the significant components in fermentation medium, while a third degree polynomial model was used for studying the relationship between the concentration of the components in fermentation medium and the yield of Epos（YEPs）. A pattern search method was used for searching the optimum fermentation medium in the test space, which was as follows（g/L）： potassium nitrate 8.00, soybean peptone 17.60, potassium hydrogen phos- phate 1.00, beef extraction 6.46, yeast extraction 1.00, calcium chloride 0.25, sodium chloride 1.00 and ferric chloride 0.02. The optimum fermentation medium was expected to result in a yield of Epos（YEPs） of 2.48 mg/L. The validation experiments with the optimum medium were performed in triplicate and the average yield of Epos was 2.45 mg/L which was 7.78 times higher than that of Epos prepared without optimization.

关键词： Statistical approach Epothilones uniform design Optimization of fermentation medium

Optimization of extraction and determination of emodin from Polygonum cuspidatum Sieb. et Zucc. products by HPLC-DAD

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Journal of Central South University of Technology 2006年第6期13卷 658-662页

作者：卢红梅梁逸曾倪网东满瑞林 School of Chemistry and Chemical Engineering Central South University

A uniform experimental design procedure was used to investigate the effects of some operating parameters on the extraction of emodin from Polygonum cuspidatum Sieb. et Zucc. products. Variables tested were volume ratio of material to solvent, size of material, extraction time and temperature and composition of extraction solvent （mixtures of acetone-water）. Each variable was tested at seven levels; 7 experiments were performed in random order. Analyses of the extracts were performed by high-performance liquid chromatography with diode array detection（HPLC-DAD）. Analytical responses were processed by using a forward regression analysis, in order to find polynomial function describing the relationship between variables and responses. For all the analytes the experimental conditions for providing the highest extraction yield inside the experimental domain considered were found. Finally, a simple, rapid and accurate analytical method was developed for the determination of emodin by high performance liquid chromatography. The separation is achieved within 25 rain on an ODS column using methanol and water as gradient mobiles. Emodin can be quantified by using external standard method detecting at 436 nm. Good linearity is obtained with correlation coefficient exceeding 0.9986 and the detection limit and the quantification limit are 1.53 and 3.23 mg/L respectively. This method shows good reproducibility for the quantification of the emodin with intra-day and inter-day relative standard deviation less than 2.3% and 5.6% respectively. Under optimized extraction conditions, the recovery of the standard is 96.5%. The validated method is successfully applied to quantify the emodin in seven Polygonum cuspidatum sieb. Et zucc. products, which provided an idea for the pre-treatment of determination of active compounds in traditional Chinese medicines.

关键词： Polygonum cuspidatum Sieb. et Zucc. emodin HPLC-DAD extraction quantification uniform design

Experimental study of ultrasonic atomizer effects on values of EC and pH of nutrient solution

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International Journal of Agricultural and Biological Engineering 2018年第5期11卷 59-64页

作者： Imran Ali Lakhiar Xingda Liu Guanqun Wang Jianmin Gao School of Agricultural Equipment Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

The objectives of this research were to reveal how main working parameters of ultrasonic atomizers would influence key properties of the atomized nutrient solution in an aeroponics *** Yamazaki tomato nutrient solution was selected as a nutrient *** design(UD)method U_(12)(12^(2)×13)was adopted to arrange the *** this test,spraying time and interval time were taken as quantitative factors with 12 levels(10,20,30,40,50,60,70,80,90,100,110,and 120 min,respectively),and ultrasonic atomizer frequency was taken as qualitative factor with 3 conditions(28 kHz,107 kHz,1.7 MHz).Based on test data,two regression formulations used to predict the values ofΔEC,andΔpH of atomized Yamazaki tomato nutrient solution was established and *** spraying interval time of ultrasonic atomizers had no significant effect on EC and pH of the atomized Yamazaki tomato nutrient solution;the ultrasonic atomizer frequency was more effective than spraying time on the values of EC and pH;the values of EC and pH became maximum at(f_(3),T_(1))=(1.7 MHz,120 min)and minimum at(f_(1),T_(1))=(28 kHz,10 min).It was concluded that the effect of high-frequency(1.7 MHz)ultrasonic atomizer on EC and pH of the Yamazaki tomato nutrient solution was beyond the standard value for tomato ***,the high-frequency(1.7 MHz)ultrasonic atomizer is not suitable for aeroponics cultivation when using the Yamazaki tomato nutrient solution as aeroponics nutrient solution.

关键词： aeroponics tomato nutrient solution EC pH ultrasonic atomizer frequency spray time interval time uniform design

Multi-Objective Structural Optimization of a Wind Turbine Tower

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Journal of Shanghai Jiaotong university(Science) 2020年第4期25卷 538-544页

作者： ZHENG Yuqiao ZHANG Lu PAN Yongxiang HE Zhe School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050China

The 2MW wind turbine tower is considered as the baseline configuration for structural *** design variables consist of the thickness and height located at the top tower *** relationships between the design variables and the optimization objectives(mass,equivalent stress,top displacement and fatigue life)are mapped on the basis of uniform design and regression ***,five solutions are developed by an algorithm,*** to their efficiency and applicability,the most suitable solution is *** approach yields a decrease of 0.48%in the mass,a decrease of 54.48%in the equivalent stress and an increase of 8.14%in fatigue life,as compared with existing tower *** improved wind turbine tower is obtained for this practice.

关键词： structural optimization wind turbine tower multi-objective optimization algorithm uniform design

Construction of column-orthogonal designs for computer experiments

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Science China Mathematics 2011年第12期54卷 2683-2692页

作者： SUN FaSheng PANG Fang LIU MinQian Department of Statistics KLAS and School of Mathematics and Statistics Northeast Normal University Changchun 130024 China Department of Statistics School of Mathematical Sciences and LPMC Nankai University Tianjin 300071 China

Latin hypercube design and uniform design are two kinds of most popular space-filling designs for computer experiments. The fact that the run size equals the number of factor levels in a Latin hypercube design makes it difficult to be orthogonal. While for a uniform design, it usually has good space-filling properties, but does not necessarily have small or zero correlations between factors. In this paper, we construct a class of column-orthogonal and nearly column-orthogonal designs for computer experiments by rotating groups of factors of orthogonal arrays, which supplement the designs for computer experiments in terms of various run sizes and numbers of factor levels and are flexible in accommodating various combinations of factors with different numbers of levels. The resulting column-orthogonal designs not only have uniformly spaced levels for each factor but also have uncorrelated estimates of the linear effects in first order models. Further, they are 3-orthogonal if the corresponding orthogonal arrays have strength equal to or greater than three. Along with a large factor-to-run ratio, these newly constructed designs are economical and suitable for screening factors for physical experiments.

关键词： computer experiment Latin hypercube design orthogonal array rotation uniform design

Quantitative relations between blowhole and coating components of stainless steel electrode

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China Welding 2006年第3期15卷 34-37页

作者：孟工戈谷丰李丹 College of Materials Science & Engineering Harbin University of Science and Technology

Using uniform design method and computer program, the experiment has been arranged, the mathematical model between blowhole resistance of stainless steel electrode and 12 coating components has been regressed. And the trend diagrams of effects of. every ingredient on the blowhole resistance have been drawn out. The mathematical model and trend diagrams revealed the complex laws between the mark of blowhole resistance and coating components. The effect of each ingredient on the mark of blowhole resistance is different, such as the mark of blowhole resistance increases with calcite increases. There are interactions among the coating components, such as the mark of blowhole resistance decreases with fluorite increases when calcite content is lower; but it increases when calche content is higher. The sieving and forecasting can be done using mathematical model and computer program.

关键词： stainless steel electrode blowhole uniform design