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Composition optimization and electrochemical characteristics of Co-free Fe-containing AB_5-type hydrogen storage alloys through uniform design

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Journal of Rare Earths 2012年第4期30卷 361-366页

作者：晁栋梁陈云贵朱昌荣吴朝玲朱丁 College of Materials Science and Engineering Sichuan University

In order to reduce the cost of ABs-type hydrogen storage alloys, effects of substitution of Ce for La （A side） and Fe, Mn, Al for Ni （B side） on structural and electrochemical properties of （LaCe）;（NiFeMnAl）s alloys were studied systematically. To make component uniform and operation easy, uniform design （UD） method was introduced into the study of composition optimization of Co-free Fe-containing ABs-type alloys for the first time. X-ray diffraction （XRD） results showed that the designed alloys were of single CaCus-type structure phase. The replacement of Fe had a severe effect on electrochemical capacity, and the substitution of Fe and A1 had a synergetic action among the unit cell volume, cycling stability and high rate discharge property. Interestingly, it was found that the hydrogen storage alloys with excessively high plateau pressure showed a tilted line in Nyquist plot instead of the semicircle, and the current decayed rapidly to near zero at the beginning of the step in constant potential step （CPS）, indicating that electrochemical impedance spectra （EIS） and CPS cannot accurately measure the electrochemical kinetics process of the hydrogen storage alloys with excessively high plateau pressure.

关键词： hydrogen storage alloy Co-free Fe-containing composition optimization electrochemical characteristics uniform design rare earths

Simulation and uniform design-based automatic generation of risk scenarios

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Journal of Systems Engineering and Electronics 2011年第6期22卷 1015-1022页

作者： Jinghui Li Rui Kang Ali Mosleh Xing Pan School of Reliability and Systems Engineering Beihang UniversityBeijing 100191P.R.China Center for Risk and Reliability University of MarylandCollege ParkMD 20742USA

This paper presents a methodology for automatically generating risk scenarios for dynamic reliability applications in which some dynamic characteristics(e.g.,the order,timing and magnitude of events,the value of relevant process parameters and initial conditions) have a significant influence on the evolution of the *** main idea of the methodology is:(i) making the system model "express itself" through simulation by having the model driven by an elaborated simulation engine;(ii) exploiting uniform design to pick out a small subset of representative design points from the space of relevant dynamic characteristics;(iii) for each selected design point,employing a depth-first systematic exploration strategy to cover all possible scenario branches at each branch point.A highly dynamic example adapted from the literature(a chemical batch reactor) is studied to test the effectiveness of the proposed methodology.

关键词： risk scenarios automatic generation simulation uniform design dynamic reliability.

Bi-objective Layout Optimization for Multiple Wind Farms Considering Sequential Fluctuation of Wind Power Using uniform design

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CSEE Journal of Power and Energy Systems 2022年第6期8卷 1623-1635页

作者： Yinghao Ma Kaigui Xie Yanan Zhao Hejun Yang Dabo Zhang Anhui Province Key Laboratory of Renewable Energy Utilization and Energy Saving Hefei University of TechnologyHefei 230009China State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqing 400044China School of Computer Science and Technology at University of Science and Technology of China Hefei 230027China

The fluctuation of wind power brings great challenges to the secure,stable,and cost-efficient operation of the power *** of the time-correlation of wind speed and the wake effect of wind turbines,the layout of wind farm has a significant impact on the wind power sequential *** order to reduce the fluctuation of wind power and improve the operation security with lower operating cost,a bi-objective layout optimization model for multiple wind farms considering the sequential fluctuation of wind power is proposed in this *** goal is to determine the optimal installed capacity of wind farms and the location of wind *** proposed model maximizes the energy production and minimizes the fluctuation of wind power *** improve the accuracy of wind speed estimation and hence the power calculation,the timeshifting of wind speed between the wind tower and turbines’locations is also considered.A uniform design based two-stage genetic algorithm is developed for the solution of the proposed *** studies demonstrate the effectiveness of this proposed model.

关键词： Wind farm layout optimization(WFLO) wind power fluctuation bi-objective optimization uniform design

Integration of uniform design and quantum-behaved particle swarm optimization to the robust design for a railway vehicle suspension system under different wheel conicities and wheel rolling radii

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Acta Mechanica Sinica 2017年第5期33卷 963-980页

作者： Yung-Chang Cheng Cheng-Kang Lee Department of Mechanical and Automation Engineering Kaohsiung First University of Science and Technology Department of Industrial Engineering and Management Cheng Shiu University

This paper proposes a systematic method, integrating the uniform design (UD) of experiments and quantum-behaved particle swarm optimization (QPSO), to solve the problem of a robust design for a railway vehicle suspension system. Based on the new nonlinear creep model derived from combining Hertz contact theory, Kalker's linear theory and a heuristic nonlinear creep model, the modeling and dynamic analysis of a 24 degree-of-freedom railway vehicle system were investigated. The Lyapunov indirect method was used to examine the effects of suspension parameters, wheel conicities and wheel rolling radii on critical hunting speeds. Generally, the critical hunting speeds of a vehicle system resulting from worn wheels with different wheel rolling radii are lower than those of a vehicle system having original wheels without different wheel rolling radii. Because of worn wheels, the critical hunting speed of a running railway vehicle substantially declines over the long term. For safety reasons, it is necessary to design the suspension system parameters to increase the robustness of the system and decrease the sensitive of wheel noises. By applying UD and QPSO, the nominal-the-best signal-to-noise ratio of the system was increased from -48.17 to -34.05 dB. The rate of improvement was 29.31%. This study has demonstrated that the integration of UD and QPSO can successfully reveal the optimal solution of suspension parameters for solving the robust design problem of a railway vehicle suspension system.

关键词： Speed-dependent nonlinear creep model Quantum-behaved particle swarm optimization uniform design Wheel rolling radius Hunting stability

Nearly uniform design Construction on Flexible Region

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Acta Mathematicae Applicatae Sinica 2020年第3期36卷 557-565页

作者： Jian-hui NING Wen-wen YIN Li PENG School of Mathematics and Statistics Center China Normal UniversityWuhan 430079China School of statistics Renmin University of ChinaBeijing 100872China Department of Statistics General Administration of Customs of the People's Republic of ChinaBeijing 100730China

In this paper,we deduced an iteration formula for the computation of central composite *** using the iteration formula,the computational complexity of uniform design construction in flexible region can be greatly *** we also made a refinement to threshold accepting algorithm to accelerate the algorithm's convergence *** show that the refined algorithm can converge to the lower discrepancy design more stably.

关键词： uniform design flexible region central composite discrepancy threshold accepting algorithm

Extraction optimization of coumarins from radix angelicae pubescentis by HPLC-DAD coupled with uniform design

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Journal of Central South University of Technology 2006年第2期13卷 156-159页

作者：郭方遒黄兰芳周火飞江秋菊 School of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China School of Chemistry and Chemical Engineering Central South UniversityChangsha 410083ChinaTechnical Center of Changde Cigarette Factory Changde 415000China

uniform design was used to optimize extraction condition of direct refluence extraction of coumarins from the Chinese traditional medicine of radix angelicae pubescentis(Duhuo); the sum peak area of coumarins separated with high performance liquid chromatography(HPLC) at detection wavelength of 320nm was considered as detection index, two factors of solvent concentration and extraction time were mainly studied at extraction temperature of 85℃ and a volume ratio of solvent to sample of 10∶1. Optimal subclass, quadric polynomial step by step aggression and neural network method were applied to process the experimental results. The results show that the first and second methods give the same factors combination (concentration of ethanol: 95%, extraction time: 3.6 h) and the second method is much better than the first one. The extraction model is consequently developed.

关键词： radix angelicae pubescentis(Duhuo) couamrins uniform design high performance liquid chromatagraphy-diode array detector(HPLC-DAD)

Process parameter optimization for local post-weld heat *** turbine rotor based on uniform design

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China Welding 2012年第3期21卷 44-49页

作者：王开云陆皓余春曹志明顾福明 School of Material Science and Engineering Shanghai Jiao Tong UniversityShanghai200240 Shanghai Institute Special Equipment Inspection&Technical Research Shanghai200062

During the process of local post-weld heat treatment （ PWHT） , the temperature difference inside the weld overlay is a very influential factor on relieving residual stress. In this paper, a commercial program （ABAQUS） was used to simulate the temperature field in turbine rotor, and the influence of heat treatment parameters on temperature was investigated by finite element method. Weight analysis shows that the holding temperature and heating rate are the main factors affecting on temperature, especially the holding temperature. Besides, two regression equations that reflect the relationship between temperature and heat treatment parameters were fitted with uniform design method. Both the correlation coefficients of the regression equations are up to O. 999 2, and the maximum residual error is only O. 7. The agreement between simulation results and regression results is shown to be excellent. At the end, local heat treatment parameters were optimized using the simplex method.

关键词： turbine rotor parameter optimization uniform design

Optimization of tensile strength for new type acetone-urea-formaldehyde furan resin using uniform design

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China Foundry 2011年第1期8卷 30-35页

作者： Lin Shengjun Zhao Wei Li Yuancai Tong Siyi Wang Wenqing School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 Hubei China Guangxi Yuchai Machinery Company Limited Yulin 537005 Guangxi China

In this study,the 24 h tensile strength of new type acetone-urea-formaldehyde furan resin (nitrogen content 3%) was investigated by uniform design *** independent variables such as acetone:formaldehyde molar ratio (mol/mol),solution pH value,reaction temperature (℃) and reaction time (min) were considered in the experiments.U13(134) uniform design was employed and the equation of 24 h tensile strength model was obtained after 13 *** 24 h tensile strength was optimized by applying single factor experiments and stepwise non-linear regression *** (Minitab 15 trial version) and MATLAB (R2010a trial version) were used for data *** t-value and p-value indicate that the major impact factors include the interaction effect of solution pH value and reaction temperature (X2X3),the linear terms of acetone:formaldehyde molar ratio (X1),reaction time (X4) followed by the square effects of acetone/formaldehyde molar ratio (X1X1).The optimized results were achieved with the acetone:formaldehyde molar ratio (mol/mol) at 3:1,solution pH value at 6.0,reaction temperature at 70℃,and reaction time at 140 min,*** method can not only significantly reduce the number and cost of the tests,but also provide a good experimental design strategy for the development of furan *** investigation shows that the predicted results of 24 h tensile strength are consistent well with the experimental ones.

关键词： acetone-urea-formaldehyde furan resin 24 h tensile strength single factor experiment uniform design stepwise regression

Optimization of Culture Conditions and Medium Composition for the Marine Algicidal Bacterium Alteromonas sp. DH46 by uniform design

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Journal of Ocean University of China 2013年第3期12卷 385-391页

作者： LIN Jing ZHENG Wei TIAN Yun WANG Guizhong ZHENG Tianling State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coast and Wetland Ecosystems School of Life SciencesXiamen University

Harmful algal blooms(HABs) have led to extensive ecological and environmental issues and huge economic *** HAB control techniques have been developed,and biological methods have been paid more *** bacteria is a general designation for bacteria which inhibit algal growth in a direct or indirect manner,and kill or damage the algal cells.A metabolite which is strongly toxic to the dinoflagellate Alexandrium tamarense was produced by strain DH46 of the alga-lysing bacterium Alteromonas *** culture conditions were optimized using a single-factor test *** including carbon source,nitrogen source,temperature,initial pH value,rotational speed and salinity were *** results showed that the cultivation of the bacteria at 28℃ and 180 r min-1with initial pH 7 and 30 salt contcentration favored both the cell growth and the lysing effect of strain *** optimal medium composition for strain DH46 was determined by means of uniform design experimentation,and the most important components influencing the cell density were tryptone,yeast extract,soluble starch,NaNO3 and *** the following culture medium was used(tryptone 14.0g,yeast extract 1.63g,soluble starch 5.0 g,NaNO3 1.6 g,MgSO4 2.3 g in 1L),the largest bacterial dry weight(7.36 g L-1) was obtained,which was an enhancement of 107% compared to the initial medium;and the algal lysis rate was as high as 98.4% which increased nearly 10% after optimization.

关键词： algicidal bacteria optimization culture conditions medium composition uniform design