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Flow Field Characteristics for Parachute-projectile System

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Chinese Journal of Mechanical Engineering 2011年第5期24卷 813-819页

作者： ZHU Yong liu li wang Zhengping School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China

In the current research for parachute flow field nowadays,the size of parachutes in previous research are so large compared with their carriers that the effects of the carriers wake flow to parachute are always *** from such large parachutes,the parachute size in this paper is on the same magnitude with the carrier,thus,the carrier can obviously affect the parachute flow *** this paper,flow field characteristics of small parachute for projectile decelerating are researched through two approaches,namely,computational fluid dynamics（CFD） simulation and wind tunnel *** parachutes with various sizes are chosen for ***,the CFD simulation of flow field around these parachutes is carried out,and then the CFD simulation of parachute-projectile systems is *** to the simulation results,the phenomenon is observed that in the simulations of parachutes there are two vortex-rings at the wind shadow of parachutes,however,in the second simulations of parachute-projectile systems,two additional vortex-rings emerge inside the *** to these two inner vortex-rings,the pressure inside parachutes *** a result,the drag of parachute in simulation of parachute-projectile systems is about 20% smaller compared with the prior *** order to verify the numerical results of CFD simulations,wind tunnel tests are *** terms of the data of the wind tunnel tests,the CFD simulation for flow field characteristics is reasonable and *** results of both CFD simulation and wind tunnel tests demonstrated the influence of projectile wake flow to parachute drag can not be neglected if the parachute size is on the same magnitude with *** influence to parachute drag from the ratio of projectile diameter to parachute diameter is also analyzed both in CFD simulations and wind tunnel *** approach combined CFD simulation and wind tunnel tests proposed can be used to guide the design of such parachute whose si

关键词： parachute projectile flow field computational fluid dynamics(CFD) wind tunnel test

Passive walker that can walk down steps:simulations and experiments

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Acta Mechanica Sinica 2008年第5期24卷 569-573页

作者： Ning liu Junfeng li Tianshu wang School of Aerospace Tsinghua UniversityBeijing 100084 China

A planar passive walking model with straight legs and round feet was discussed. This model can walk down steps, both on stairs with even steps and with random steps. Simulations showed that models with small moments of inertia can navigate large height steps. Period-doubling has been observed when the space between steps grows. This period-doubling has been validated by experiments, and the results of experiments were coincident with the simulation.

关键词： Passive walking Period-doubling ,Simulation - Experiments Poincaré map ,Nonlinear dynamics

Model predictive control for adaptive cruise control with multi-objectives: comfort,fuel-economy,safety and car-following

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第3期11卷 191-201页

作者： li-hua LUO Hong liu Ping li Hui wang State Key Laboratory of Industrial Control Technology Zhejiang UniversityHangzhou 310027China

For automated vehicles,comfortable driving will improve passengers’ *** fuel consumption brings economic profits for car owners,decreases the impact on the environment and increases energy *** addition to comfort and fuel-economy,automated vehicles also have the basic requirements of safety and *** this purpose,an adaptive cruise control (ACC) algorithm with multi-objectives is proposed based on a model predictive control (MPC) *** the proposed ACC algorithm,safety is guaranteed by constraining the inter-distance within a safe range; the requirements of comfort and car-following are considered to be the performance criteria and some optimal reference trajectories are introduced to increase *** performances of the proposed ACC algorithm are simulated and analyzed in five representative traffic scenarios and multiple *** results show that not only are safety and car-following objectives satisfied,but also driving comfort and fuel-economy are improved significantly.

关键词： Adaptive cruise control (ACC) Multi-objectives Comfort Fuel-economy Model predictive control (MPC)

G-protein beta 3 subunit polymorphisms and essential hypertension： a case-control association study in northern Han Chinese

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Journal of Geriatric Cardiology 2015年第2期12卷 127-134页

作者： Mei li Bei ZHANG Chuang li Jie-lin liu li-Juan wang Ya liu Zuo-Guang wang Shao-Jun WEN Department of Hypertension Research Beijing Anzhen Hospital Capital Medical University and Beijing Institute of Heart Lung and Blood Vessel DiseasesBeijing 100029 China

Objective To explore the association between the three polymorphisms [ C825T, C1429T and G（-350）A] of the gene encoding the G protein beta 3 subunit （GNB3） and hypertension by performing a case-control study in the northern Han Chinese population. Methods We recnaited 731 hypertensive patients and 673 control subjects （the calculated power value was 〉 0.8）. Genotyping was performed to identify C825T, C1429T and G（-350）A polymorphisms using the TaqMan assay. Comparisons of allelic and genotypic frequencies between cases and controls were made by using the chi-square test. Logistic regression analyses were performed to investigate the relationships between the three polymorphisms of GNB3 gene under different genetic models （additive, dominant and recessive models）. Results The genotype dis- tribution and allele frequencies of C825T, C1429T and G（-350）A polymorphisms did not differ significantly between hypertensive patients and control subjects, either when the full sample was assessed, or when the sample was stratified by gender. No significant association was observed between C825T, C 1429T and G（-350）A polymorphisms and the risk of essential hypertension in any genetic model. linkage dis- equilibrium was only detected between C825T and C 1429T polymorphisms. Haplotype analyses observed that none of the three estimated haplotypes significantly increased the risk of hypertension. Conclusions Our study suggested that the GNB3 gene polymorphisms [C825T, C 1429T and G（-350）A] were not significantly associated with essential hypertension in northern Han Chinese population.

关键词： G protein beta 3 subunit gene Haplotype Hypertension Polymorphism

A novel protein refolding method integrating ion exchange chromatography with artificial molecular chaperone

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Chinese Chemical Letters 2008年第5期19卷 595-598页

作者： Qin Ming Zhang Chao Zhan wang Jiang Feng liu li li wang Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education Institute of Modern Separation Science Key Laboratory of Separation Science in Shanxi Province Department of Chemistry Northwest University Xi＇an 710069 China

Artificial molecular chaperone （AMC） and ion exchange chromatography （IEC） were integrated, thus a new refolding method, artificial molecular chaperone-ion exchange chromatography （AMC-IEC） was developed. Compared with AMC and IEC, the activity recovery of lysozyme obtained by AMC-IEC was much higher in the investigated range of initial protein concentrations, and the results show that AMC-IEC is very efficient for protein refolding at high concentrations. When the initial concentration of lysozyme is 180 mg/mL, its activity recovery obtained by AMC-IEC is still as high as 76.6%, while the activity recoveries obtained by AMC and IEC are 45.6% and 42.4%, respectively.

关键词： Artificial molecular chaperone Ion exchange chromatography Protein refolding Lysozyme Protein folding liquid chromatography

Research on consistency measurement and weight estimation approach of hybrid uncertain comparison matrix

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Journal of Systems Engineering and Electronics 2008年第6期19卷 1145-1150页

作者： Zhu Jianjun Zhu Ningning liu Sifeng li Tao wang Hehua Coll. of Economics and Management Nanjing Univ. of Aeronautics and Astronautics Nanjing 210016 P. R. China

The consistency measurement and weight estimation approach of the hybrid uncertain comparison matrix in the analytic hierarchy process （AHP） are studied. First, the decision-making satisfaction membership function is defined based on the decision making＇s allowable error. Then, the weight model based on the maximal satisfactory consistency idea is suggested, and the consistency index is put forward. Moreover, the weight distributing value model is developed to solve the decision making misleading problem since the multioptimization solutions in the former model. Finally, the weights are ranked based on the possibility degree approach to obtain the ultimate order.

关键词： analytic hierarchy process, uncertainty hybrid comparison matrix, weight

Determination of Enantiomeric Excess of Glutamic Acids by Lab-made Capillary Array Electrophoresis

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Chinese Chemical Letters 2006年第1期17卷 49-52页

作者： Jun wang Kai Ying liu li wang Ji ling BAI State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023

Simulated enantiomeric excess of glutamic acid was determined by a lab-made sixteen-channel capillary array electrophoresis with confocal fluorescent rotary scanner. The experimental results indicated that the capillary array electrophoresis method can accurately determine the enanfiomefic excess of glutamic acid and can be used for high-throughput screening system for combinatorial asymmetric catalysis.

关键词： Capillary array electrophoresis enantiomeric excess glutamic acid.

Multi-Class Classification Methods of Cost-Conscious LS-SVM for Fault Diagnosis of Blast Furnace

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Journal of Iron and Steel Research International 2011年第10期18卷 17-23,33页

作者： liu li-mei wang An-na SHA Mo ZHAO Feng-yun College of Information Science and Engineering Northeastern University Shenyang 110819 Liaoning China

Aiming at the limitations of rapid fault diagnosis of blast furnace, a novel strategy based on cost-conscious least squares support vector machine （LS-SVM） is proposed to solve this problem. Firstly, modified discrete particle swarm optimization is applied to optimize the feature selection and the LS-SVM parameters. Secondly, cost-con- scious formula is presented for fitness function and it contains in detail training time, recognition accuracy and the feature selection. The CLS-SVM algorithm is presented to increase the performance of the LS-SVM classifier. The new method can select the best fault features in much shorter time and have fewer support vectbrs and better general- ization performance in the application of fault diagnosis of the blast furnace. Thirdly, a gradual change binary tree is established for blast furnace faults diagnosis. It is a multi-class classification method based on center-of-gravity formula distance of cluster. A gradual change classification percentage ia used to select sample randomly. The proposed new metbod raises the sped of diagnosis, optimizes the classifieation scraraey and has good generalization ability for fault diagnosis of the application of blast furnace.

关键词： blast furnace fault diagnosis eosc-conscious LS-SVM multi-class classification

Identification and Molecular Mapping of the Rs Dm R Locus Conferring Resistance to Downy Mildew at Seedling Stage in Radish(Raphanus sativus L.)

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Journal of Integrative Agriculture 2014年第11期13卷 2362-2369页

作者： XU liang JIANG Qiu-wei WU Jian wang Yan GONG Yi-qin wang Xian-li limera Cecilia liu li-wang National Key Laboratory of Crop Genetics and Germplasm Enhancement/Engineering Research Center of Horticultural Crop Germplasm Enhancement and Utilization Ministry of Education/College of Horticulture Nanjing Agricultural University Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences

Downy mildew （DM）, caused by the fungus Peronospora parasitica, is a destructive disease of radish （Raphanus sativus L.） worldwide. Host resistance has been considered as an attractive and environmentally friendly approach to control the disease. However, the genetic mechanisms of resistance in radish to the pathogen remain unknown. To determine the inheritance of resistance to DM, F1, F2 and BC1F1 populations derived from reciprocal crosses between a resistant line NAU-dhp08 and a susceptible line NAU-qtbjq-06 were evaluated for their responses to DM at seedling stage. All F1 hybrid plants showed high resistance to DM and maternal effect was not detected. The segregation for resistant to susceptible individuals statistically iftted a 3：1 ratio in two F2 populations （F2（SR） and F2（RS））, and 1：1 ratio in two BC1F1 populations, indicating that resistance to DM at seedling stage in radish was controlled by a single dominant locus designated as RsDmR. A total of 1 972 primer pairs （1 036 SRAP, 628 RAPD, 126 RGA, 110 EST-SSR and 72 ISSR） were screened, and 36 were polymorphic between the resistant and susceptible bulks, and consequently used for genotyping individuals in the F2 population. Three markers （Em9/ga24370, NAUISSR826700 and Me7/em10400） linked to the RsDmR locus within a 10.0 cM distance were identiifed using bulked segregant analysis （BSA）. The SRAP marker Em9/ga24370 was the most tightly linked one with a distance of 2.3 cM to RsDmR. These markers tightly linked to the RsDmR locus would facilitate marker-assisted selection and resistance gene pyramiding in radish breeding programs.

关键词： Raphanus sativus L. molecular mapping downy mildew seedling-stage resistance marker assisted selection