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Regional variance analysis of Innovation Output in China

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Regional Variance Analysis of Innovation Output in China

A new integrated model of deformation resistance and its application in prediction of rolling force of a thick plate

2011 International Conference on Business Management and Electronic Information(BMEI 2011)

作者： Chen li 1 2 1.Management school Huazhong University of Science and Technology 2.School of Business Administration Hubei University of Economics Wuhan China Yu xiang Management school Huazhong University of Science and Technology Wuhan China

In order to study regional technological innovation output capability for an overall understanding,this paper finds the technological innovation output can be decomposed into two kinds through factor analysis:short-term S＆T application output and independent innovation *** find the regional differences in these two outputs,the paper Building a scientific measurement of regional S＆T supply and demand model based on the analysis of the influence factors of the innovation output,by which the basic situation of regional S＆T supply and demand in China is ***,the relationship between regional innovation out and S＆T supply and demand characteristics is found by an empirical *** empirical results show that the independent innovation output in China is strongly correlated to the high S＆T supply,but is not to the local S＆T demand,indicating the development of regional S＆T has not yet entered the demand-driven *** the short-term S＆T applications,such as technology trade,technology transfer,there is no significant difference across *** universal problem need to solve is how to strengthen the technology market mechanisms to promote virtuous circle of R＆D and application.

关键词： innovation output S&T supply and demand model factors analysis variance analysis

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Journal of Iron and Steel Research International 2024年第4期31卷 882-893页

作者： Shun-hu Zhang Yan Li Li-zhi Che Wen-hao Tian Shagang School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

The prediction accuracy of existing models of the rolling force of a thick plate is always very *** address this problem,a high-precision genetic algorithm-backpropagation network(GA-BP)model of deformation resistance was built,and its integration with the traditional fitted model was further ***,a novel rolling force model was obtained by embedding the integration model of deformation resistance in the original model of rolling *** to this research idea,the industrial data are normalized at *** this basis,the interactions among the process parameters were disclosed through the variance analysis,and then described by various virtual *** factors are set as part of input ***,the optimal structure of the GA-BP model of deformation resistance was determined and an integration model of deformation resistance was ***,a novel rolling force model is obtained by substituting the traditional fitted deformation resistance into the Sims model with the integration model of the deformation *** results proves that the introduction of virtual factors can increase the hit rate of±5%from 75.8%to 78%and can reduce the root mean square error from 4.72%to 4.48%.Besides,it is found that the mean relative error of the traditional fitted deformation resistance is 0.142,while that of the modified deformation resistance is only *** addition,the mean relative error in the original rolling force model is 0.145,while that of the present model is only 0.03.

关键词： Integration model-Deformation resistance variance analysis Virtual factor Genetic algorithm-backpropagation network model

Evaluation of Dry Sliding Wear Behaviour of Plasma Transferred Arc Hardfaced Stainless Steel

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Journal of Iron and Steel Research International 2009年第4期16卷 49-54页

作者： C S Ramachandran V Balasubramanian R Varahamoorthy Centre for Materials Joining and Research(CEMAJOR) Department of Manufacturing EngineeringAnnamalai University

The effects of different experimental conditions on the dry sliding wear behavior of stainless steel surface produced by plasma transferred arc （PTA） hardfacing process were studied. The wear test was conducted in a pinon-roller wear testing machine, at constant sliding distance of 1 kin. Mathematical models were developed to estimate wear rate incorporating with rotational speed, applied load and roller hardness using statistical tools such as design of experiments, regression analysis and analysis of variance. It is found that the wear resistance of the PTA hardfaced stainless steel surface is better than that of the carbon steel substrate.

关键词： dry sliding wear plasma transferred arc hardfacing carbon steel stainless steel variance analysis experimental design

Physical and mechanical properties of hydroponic lettuce for automatic harvesting

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Information Processing in Agriculture 2021年第4期8卷 550-559页

作者： Wenqi Wang Yidong Ma Longsheng Fu Yongjie Cui Yaqoob Majeed College of Mechanical and Electronic Engineering Northwest A&F UniversityYanglingShaanxi 712100China Key Laboratory of Agricultural Internet of Things Ministry of Agriculture and Rural AffairsYangling 712100China Shaanxi Key Laboratory of Agricultural Information Perception and Intelligent Service Yangling 712100China College of Agricultural Equipment Engineering Henan University of Science and TechnologyLuoyang 471003China Centre for Precision and Automated Agricultural Systems Washington State UniversityProsserWA 99350USA

To design an automatic harvesting machine for hydroponic lettuce(Lactuca sativa L.),physical and mechanical properties of hydroponic lettuce were investigated and *** content of stem,root and leaf,geometric characteristics,pulling force,and root cutting force were studied for harvesting hydroponic *** pulling force was examined by a tensile experiment,while the root cutting force was investigated by a shear experiment on the electronic universal testing *** moisture content of hydroponic lettuce was obtained by direct *** data were processed using regression analysis and mathematical statistics method.A regression equation and the law of numerical distribution were *** results showed that the geometric size of different hydroponic lettuce had little difference,and the distribution of physical parameters was *** content was found statistically similar in stem and root(around 91%),while the highest moisture content was found in the leaf of 95.73%.The root cutting force decrease with the increase of cutting speed and decrease with the cutting position move *** minimum average root cutting force in the experiment was 1.41 *** average pulling force was 13 *** study provides adequate theoretical support for the design of the automatic harvesting machine of hydroponic lettuce.

关键词： Greenhouse vegetable Harvester variance analysis Response surface

DYNAMIC FINITE ELEMENT MODEL UPDATING BASED ON GLOBAL INFORMATION OF STRUCTURES

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Chinese Journal of Mechanical Engineering 2005年第2期18卷 294-296页

作者： FeiQingguo ZhangLingmi GuoQintao CollegeofCivilEngineering SoutheastUniversityNanjing210096China CollegeofAerospaceEngineering NanjingUniversityofAeronauticsandAstronauticsNanjing210016China

Finite element model updating method based on global information is *** investigation upon design space of structural parameters is performed before updating usingstatistic analysis, including parameter screening using variance analysis and response surfacefitting using regression analysis. The parameter screening method selects the design parametersconsidering the result of hypothesis testing, which is a kind of global information. Meanwhile, thetraditional updating method considers local sensitivity which only gives the information at solepoint in the design space. Response surface fitting constructs a close-form multinomial whichdescribes the relationship between concerned structural feature and selected updating parameters. Itis an approximation to finite element models(FEM) and used as a substitution in the updatingiterations. The presented updating method can be applied without the restriction of linearassumption. In addition, there is no data exchange between the updating program and the finite-element analysis program in the updating iterations. This makes the method practical inengineering. An aircraft test structure, GARTEUR, is employed to verify the effectiveness of themethod. After updating, the error of modal frequencies is less than 3 percent.

关键词： Model updating Design of experiment variance analysis Regression analysis Response surface methodology

Optimization of Factors Influencing Adventitious Rooting in Hybrid Larch

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Phyton-International Journal of Experimental Botany 2021年第2期90卷 583-593页

作者： Kuipeng Li Hua Han Yunhui Xie Xiaomei Sun State Key Laboratory of Tree Genetics and Breeding Key Laboratory of Tree Breeding and Cultivation of State Forestry and Grassland AdministrationResearch Institute of ForestryChinese Academy of ForestryBeijing100091China Guangxi Key Laboratory of Superior Timber Trees Resource Cultivation&Key Laboratory of Central South Fast-Growing Timber Cultivation of Forestry Ministry of China Guangxi Forestry Research InstituteNanning530002China

Optimization of in vitro adventitious root induction contributes to the development of a large-scale production system of hybrid clone seedlings of larch(Larix spp.).We used orthogonal testing to investigate the factors that affect the rooting of hybrid larch shoots-activated carbon,vitamin B1,sucrose,glycine,glutamic acid(Glu),cysteine,pH,and induction time in the dark and indole-3-butyric acid(IBA).variance analysis showed that the effects of sucrose concentration on rooting rate,survival rate,and average root number,pH on the average number of roots;and Glu on survival rate were all significant(p<0.05)when compared to the mock *** all of the 45 treatments,the highest rooting rate was 90%,the highest survival rate was 100%,and the highest average root number was *** theoretically optimal procedure of in vitro root induction of hybrid larch shoots is shoot induction on L9 modified medium(pH 6.7)containing 2 mg.L^(-1)naphthalene acetic acid,0.25 mg.L^(-1)IBA,1/3 macroelements,7.5 g.L^(-1)sucrose,and 5 mg.L^(-1)Glu for 8 days,and then root induction on L9 modified medium without auxin.

关键词： Hybrid larch adventitious root orthogonal test variance analysis

Parameter optimization and experiment of the negative pressure precision seed-metering device for wheat

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 154-162页

作者： Yubo Feng Xiaoshun Zhao Jincai Li Huali Yu Hongpeng Zhao Baozhong Yin State Key Laboratory of North China Crop Improvement and Regulation Hebei Agricultural UniversityBaoding 071001HebeiChina College of Mechanical and Electrical Engineering Hebei Agricultural UniversityBaoding 071001HebeiChina College of Plant Protection Hebei Agricultural UniversityBaoding 071001HebeiChina

In order to ensure the most reasonable distribution of wheat seeds in the field to improve seeding quality and uniformity,a set of negative pressure precision seed-metering device was designed,which shares a hollow *** seed-metering device can sow two rows of *** the STAR-CCM+,the analysis of nephogram,vectogram and streamline graph showed that more ideal structural parameters of the seed-metering device are 0.5 mm width of the slit sucking seed(WSS),150-200 mm diameter of the seed-metering disc(DSD),2.0 mm axial depth of air chamber in the seed-metering disc(ADS),and arc-shaped cross-section shape of the ring groove sucking seed(CSGS).Single-factor test on the JPS-12 test-bed analyzed the influence of the CSGS,WSS,DSD,and ADS on the qualified index(Iq),multiple index(Imul),miss index(Imiss)and coefficient of variation of qualified seed spacing(CV).Through the orthogonal on the JPS-12 test-bed,it is found that the influence of vacuum negative pressure and seed-metering device shaft speed is significant on the Iq,Imiss and *** on these,the structural parameters of the seed-metering device were *** DSD is 180 mm,the WSS is 0.7 mm,the ADS is 2.5 mm,and the CSGS is *** optimization seed-metering device was tested on the JPS-12 *** Iq is 86.66%,the Imiss is 5.09%,the Imul is 8.25%,and the CV is 24.50%.These testing results fully coincide with the standard JB/T 10293-2013 Specifications of single seed drill(precision drill).The seed-metering device meets fully the requirements for wheat precision seeding.

关键词： wheat seed-metering device negative pressure precision parameter optimization STAR-CCM+ orthogonal test variance analysis

analysis of Wind Power Assessment Based on the WRF Model

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Atmospheric and Oceanic Science Letters 2014年第2期7卷 126-131页

作者： LI Ji-Hang GUO Zhen-Hai WANG Hui-Jun LI Ji-Hang WANG Hui-Jun Nansen-Zhu International Research Centre (NZC) Institute of Atmospheric Physics the Chinese Academy of Sciences Beijing 100029 China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China University of the Chinese Academy of Sciences Beijing 100049 China

Assessing wind energy is a key step in selecting a site for a wind farm. The accuracy of the assessment is essential for the future operation of the wind farm. There are two main methods for assessing wind power: one is based on observational data and the other relies on mesoscale numerical weather prediction(NWP). In this study, the wind power of the Liaoning coastal wind farm was evaluated using observations from an anemometer tower and simulations by the Weather Research and Forecasting(WRF) model, to see whether the WRF model can produce a valid assessment of the wind power and whether the downscaling process can provide a better evaluation. The paper presents long-term wind data analysis in terms of annual, seasonal, and diurnal variations at the wind farm, which is located on the east coast of Liaoning Province. The results showed that, in spring and summer, the wind speed, wind direction, wind power density, and other main indicators were consistent between the two methods. However, the values of these parameters from the WRF model were significantly higher than the observations from the anemometer tower. Therefore, the causes of the differences between the two methods were further analyzed. There was much more deviation in the original material, National Centers for Environmental Prediction(NCEP) final(FNL) Operational Global analysis data, in autumn and winter than in spring and summer. As the region is vulnerable to cold-air outbreaks and windy weather in autumn and winter, and the model usually forecasted stronger high or low systems with a longer duration, the predicted wind speed from the WRF model was too large.

关键词： wind power assessment anemometer tower data WRF model variance analysis

Numerical investigation on the sensitivity of jointed rock mass strength to various factors

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Mining Science and Technology 2010年第4期20卷 530-534页

作者： NIU Shuangjian JING Hongwen HU Kun YANG Dafang State Key Laboratory of Geomechanics and Deep Underground Engineering China University of Mining & Technology Xuzhou 221008 China School of Civil Engineering Henan Polytechnic University Jiaozuo 454003 China

The mechanical properties of jointed rock masses, such as strength, deformation and the failure mechanism, can be understood only by studying the sensitivity of jointed rock mass strength (both the peak and residual strengths) to the factors that affect it. An orthogonal design of uniaxial compression tests was simulated on eighteen groups of jointed rock specimens having different geometric and mechanical properties using RFPA2D (Rock Failure Process analysis) code. The results show that the peak strength is controlled by the geometric parameters of the joints, but that the residual strength is controlled by the mechanical prop- erties of the joint interfaces. The failure mode of jointed rock specimens is mainly shear failure. Joint quantity, or density, is the most important index that affects jointed rock mass strength and engineering quality.

关键词： jointed rock mass peak strength residual strength variance analysis sensitivity