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Linking a farmer crop selection model(FCS) with an agronomic model(EPIC) to simulate cropping pattern in Northeast China 被引量:2
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作者 HE Ying-bin CAI Wei-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第10期2417-2425,共9页
In this paper, authors established a farmer crop selection model(FCS) for the three provinces of Liaoning, Jilin and Heilongjiang of the Northeast China. With linking to the environmental policy integrated climate m... In this paper, authors established a farmer crop selection model(FCS) for the three provinces of Liaoning, Jilin and Heilongjiang of the Northeast China. With linking to the environmental policy integrated climate model(EPIC), the simulated results of FCS model for maize, rice and soybean were spatialized with 1 km×1 km grids to obtain cropping pattern. The reference map of spatial distribution for the three staple crops acquired by remote sensing imageries was applied to validate the simulated cropping pattern. The results showed that(1) the total simulation accuracy for the study area was 78.62%, which proved simulation method was applicable and feasible;(2) simulation accuracy for Jilin Province was the highest among the three provinces with a rate of 82.45% since its simple cropping system and not complex topography;(3) simulation accuracy for maize was the best among the three staple crops with a ratio of 81.14% because the study area is very suitable for maize growth. We hope this study could provide the reference for cropping pattern forecasting and decision-making. 展开更多
关键词 cropping pattern staple crops EPIC model FCS model simulation
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Modeling study on the flow patterns of gas–liquid flow for fast decarburization during the RH process 被引量:2
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作者 Yi-hong Li Yan-ping Bao +2 位作者 Rui Wang Li-feng Ma Jian-sheng Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第2期153-163,共11页
A water model and a high-speed video camera were utilized in the 300-t RH equipment to study the effect of steel flow patterns in a vacuum chamber on fast decarburization and a superior flow-pattern map was obtained d... A water model and a high-speed video camera were utilized in the 300-t RH equipment to study the effect of steel flow patterns in a vacuum chamber on fast decarburization and a superior flow-pattern map was obtained during the practical RH process. There are three flow patterns with different bubbling characteristics and steel surface states in the vacuum chamber: boiling pattern(BP), transition pattern(TP), and wave pattern(WP). The effect of the liquid-steel level and the residence time of the steel in the chamber on flow patterns and decarburization reaction were investigated, respectively. The liquid-steel level significantly affected the flow-pattern transition from BP to WP, and the residence time and reaction area were crucial to evaluate the whole decarburization process rather than the circulation flow rate and mixing time. A superior flow-pattern map during the practical RH process showed that the steel flow pattern changed from BP to TP quickly, and then remained as TP until the end of decarburization. 展开更多
关键词 modeling study flow pattern vacuum chamber residence time decarburization RH process
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Nanoindentation Models of Monolayer Graphene and Graphyne under Point Load Pattern Studied by Molecular Dynamics
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作者 向浪 吴建 +2 位作者 马双英 王芳 张凯旺 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第9期108-111,共4页
Molecular dynamics simulations are performed to study the nanoindentation models of monolayer suspended graphene and graphyne. Fullerenes are selected as indenters. Our results show that Young's modulus of monolayer-... Molecular dynamics simulations are performed to study the nanoindentation models of monolayer suspended graphene and graphyne. Fullerenes are selected as indenters. Our results show that Young's modulus of monolayer-thick graphyne is almost half of that of graphene, which is estimated to be 0.50 TPa. The mechanical properties of graphene and graphyne are different in the presence of strain. A pre-tension has an important effect on the mechanical properties of a membrane. Both the pre-tension and Young's modulus plots demonstrate index behavior. The toughness of graphyne is stronger than that of graphene due to Young's modulus magnitude. Young's moduli of graphene and graphyne are almost independent of the size ratio of indenter to membrane. 展开更多
关键词 Nanoindentation Models of Monolayer Graphene and Graphyne under Point Load pattern Studied by Molecular Dynamics
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Rapid determination of tannin in Danshen and Guanxinning injections using UV spectrophotometry for quality control 被引量:1
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作者 Hongxia Huang Yuanyuan Lv +3 位作者 Xiaoyi Sun Shuangshuang Fu Xuefang Lou Zengmei Liu 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2018年第6期33-42,共10页
A technique for the determination of tannin content in traditional Chinese medicine injections(TCMI)was developed based on ultraviolet(UV)spectroscopy.Chemometrics were used to construct a mathematical model of absorp... A technique for the determination of tannin content in traditional Chinese medicine injections(TCMI)was developed based on ultraviolet(UV)spectroscopy.Chemometrics were used to construct a mathematical model of absorption spectrum and tannin reference content of Danshen and Guanxinning injections,and the model was veried and applied.The results showed that the established UV-based spectral partial least squares regression(PLS)tannin content model performed well with a correlation coefficient(r)of 0.952,root mean square error of calibration(RMSEC)of 0.476g/ml,root mean square error of validation(RMSEV)of 1.171g/ml,and root mean square error of prediction(RMSEP)of 0.465g/ml.Pattern recognition models using linear discriminant analysis(LDA)and k nearest neighbor(k-NN)classiers based on UV spectrum could successfully classify different types of injections and different manufacturers.The established method to measure tannin content based on UV spectroscopy is simple,rapid and reliable and provides technical support for quality control of tannin in Chinese medicine injections. 展开更多
关键词 Ultraviolet spectrum tannin content traditional Chinese medicine injection pattern recognition model partial least squares regression
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Method to generate training samples for neural network used in target recognition
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作者 何灏 罗庆生 +2 位作者 罗霄 徐如强 李钢 《Journal of Beijing Institute of Technology》 EI CAS 2012年第3期400-407,共8页
Training neural network to recognize targets needs a lot of samples.People usually get these samples in a non-systematic way,which can miss or overemphasize some target information.To improve this situation,a new meth... Training neural network to recognize targets needs a lot of samples.People usually get these samples in a non-systematic way,which can miss or overemphasize some target information.To improve this situation,a new method based on virtual model and invariant moments was proposed to generate training samples.The method was composed of the following steps:use computer and simulation software to build target object's virtual model and then simulate the environment,light condition,camera parameter,etc.;rotate the model by spin and nutation of inclination to get the image sequence by virtual camera;preprocess each image and transfer them into binary image;calculate the invariant moments for each image and get a vectors' sequence.The vectors' sequence which was proved to be complete became the training samples together with the target outputs.The simulated results showed that the proposed method could be used to recognize the real targets and improve the accuracy of target recognition effectively when the sampling interval was short enough and the circumstance simulation was close enough. 展开更多
关键词 pattern recognition training samples for neural network model emulation space coordinate transform invariant moments
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POSITIVITY-PRESERVING LOCAL DISCONTINUOUS GALERKIN METHOD FOR PATTERN FORMATION DYNAMICAL MODEL IN POLYMERIZING ACTIN FLOCKS
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作者 Xiuhui Guo Lulu Tian +1 位作者 Yang Yang Hui Guo 《Journal of Computational Mathematics》 SCIE CSCD 2023年第4期623-642,共20页
In this paper,we apply local discontinuous Galerkin(LDG)methods for pattern formation dynamical model in polymerizing actin focks.There are two main dificulties in designing effective numerical solvers.First of all,th... In this paper,we apply local discontinuous Galerkin(LDG)methods for pattern formation dynamical model in polymerizing actin focks.There are two main dificulties in designing effective numerical solvers.First of all,the density function is non-negative,and zero is an unstable equilibrium solution.Therefore,negative density values may yield blow-up solutions.To obtain positive numerical approximations,we apply the positivitypreserving(PP)techniques.Secondly,the model may contain stif source.The most commonly used time integration for the PP technique is the strong-stability-preserving Runge-Kutta method.However,for problems with stiff source,such time discretizations may require strictly limited time step sizes,leading to large computational cost.Moreover,the stiff source any trigger spurious filament polarization,leading to wrong numerical approximations on coarse meshes.In this paper,we combine the PP LDG methods with the semi-implicit Runge-Kutta methods.Numerical experiments demonstrate that the proposed method can yield accurate numerical approximations with relatively large time steps. 展开更多
关键词 pattern formation dynamical model Local discontinuous Galerkin method Positive-preserving technique Semi-implicit Runge-Kutta method Stiff source
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Layered Software Patterns for Data Analysis in Big Data Environment 被引量:3
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作者 Hossam Hakeem 《International Journal of Automation and computing》 EI CSCD 2017年第6期650-660,共11页
The proliferation of textual data in society currently is overwhelming, in particular, unstructured textual data is being constantly generated via call centre logs, emails, documents on the web, blogs, tweets, custome... The proliferation of textual data in society currently is overwhelming, in particular, unstructured textual data is being constantly generated via call centre logs, emails, documents on the web, blogs, tweets, customer comments, customer reviews, etc.While the amount of textual data is increasing rapidly, users ability to summarise, understand, and make sense of such data for making better business/living decisions remains challenging. This paper studies how to analyse textual data, based on layered software patterns, for extracting insightful user intelligence from a large collection of documents and for using such information to improve user operations and performance. 展开更多
关键词 Big data data analysis patterns layered structure data modelling
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Numerical simulation of nanoparticle pattern fabricated by electrostatic spray deposition 被引量:1
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作者 Wei Wei Zhaolin Gu +5 位作者 Sheng Wang Takeshi Fukuda Kiwamu Kase Jungmyoung Ju Yutaka Yamagata Yusuke Tajima 《Particuology》 SCIE EI CAS CSCD 2013年第1期20-24,共5页
Electrospray deposition (ESD) as a patterning method of nanoparticles deposited on a substrate has attracted much attention due to several advantages over other methods. However, obtaining an optimum ESD processing ... Electrospray deposition (ESD) as a patterning method of nanoparticles deposited on a substrate has attracted much attention due to several advantages over other methods. However, obtaining an optimum ESD processing condition for nanoparticle pattern relies much on trial experiments because of the lack of reliable numerical simulation. In this study, the deposition characteristics of nanoparticle generated by electrospray were investigated by using a three-dimensional Lagrangian model. Three important process parameters, including solution dielectric constant, applied voltage and surface charge density on mask were considered by fixing the geometrical parameters of the ESD device. Simulation result showed that under the condition of without a mask, the spray diameter increases with increasing solvent dielectric constant, and higher applied voltage makes the spray area wider. Controllability of focusing by changing surface charge density on the mask was confirmed: higher surface charge density on the mask results in more focused deposition. Validity of the numerical simulation developed in this study was verified by comnarison with exoerimental data. 展开更多
关键词 Nanoparticle pattern Electrospray deposition Deposition characteristics Lagrangian model
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Modeling the control mechanism for generating the rise-fall patterns in FO contours 被引量:1
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作者 NI Jinfu and WANG Renhua(Department of Electronic Engineering and Information Science, University of Science and Technology of China Hefei 230027) 《Chinese Journal of Acoustics》 1997年第4期339-349,共11页
The strategy of modeling the control mechanism for generating F0 contour of speech signal is studied in this paper. Based on some dynamic characteristics of vocal cord strain, the complex laryngeal mechanism relative ... The strategy of modeling the control mechanism for generating F0 contour of speech signal is studied in this paper. Based on some dynamic characteristics of vocal cord strain, the complex laryngeal mechanism relative to local F0 regulation is simplified to be a feasible physical model. Furthermore, a model function is deduced as the control mechanism for the generation process of local rise-fall patterns, and two kinds of basic feature patterns result with so called rise-fall commands defined by model parameters. on the logarithmic scale of F0 versus time the local characteristics of an F0 contour are approximated by the sum of these patterns generated by appropriate commands. The experimenial results in analyzing and synthesizing the F0 contours of spoken Chinese utterances indicate that the observed F0 contours can be always approximated well by the model, and a good correlation exists between some model parameters and the transition duration of local F0 rising or falling. The model lays a foundation for Chinese F0 contour synthesis by rule. 展开更多
关键词 Modeling the control mechanism for generating the rise-fall patterns in FO contours
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Modeling of strain and filtration properties of a semi-finished leather product
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作者 A.Amanov S.R.Khurramov +2 位作者 G.A.Bahadirov A.Abdukarimov T.Y.Amanov 《Journal of Leather Science and Engineering》 2021年第1期158-165,共8页
A study on deformation and filtration properties of a leather semi-finished product after chrome tanning are presented.The analytical dependences of compressive load on compressive(recovery)strain and moisture content... A study on deformation and filtration properties of a leather semi-finished product after chrome tanning are presented.The analytical dependences of compressive load on compressive(recovery)strain and moisture content of a leather semi-finished product are obtained.The empirical dependences of hydraulic gradient on filtration rates are determined for various compression ratios of the leather semi-finished product.It was revealed that with an increase in compressive load and moisture content of the leather semi-finished product,the compressive deformation increases.The shoulder section is subject to the greatest deformation,then the belly section and the least deformation is observed in the butt section.A linear relationship has been established between the hydraulic gradient and the rate of moisture filtration through the leather semi-finished product in the directions perpendicular and parallel to its surface. 展开更多
关键词 Semi-finished leather product Strain properties Filtration properties Mathematical models of leather filtration properties Mathematical models of leather strain patterns
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