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Consistency of Water Production Function Models of Two Crops 被引量:1
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作者 樊鹏 王莹 +1 位作者 杨青伟 杨喜会 《Agricultural Science & Technology》 CAS 2016年第1期12-14,共3页
On basis of test information, the research performed analysis on water production function models of two crops, which indicated that water model of crops in whole growth stage and water model of crops indifferent grow... On basis of test information, the research performed analysis on water production function models of two crops, which indicated that water model of crops in whole growth stage and water model of crops indifferent growth stages have consistency as well as differences, providing references for optimization of irrigation water. Meanwhile, the research analyzed the deficiency of optimization on irrigation water for crops just by Jensen model. 展开更多
关键词 Water production function Parabolic model Jensen model consistency
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CONSISTENCY OF LS ESTIMATOR IN SIMPLE LINEAR EV REGRESSION MODELS 被引量:13
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作者 刘继学 陈希孺 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期50-58,共9页
Consistency of LS estimate of simple linear EV model is studied. It is shown that under some common assumptions of the model, both weak and strong consistency of the estimate are equivalent but it is not so for quadra... Consistency of LS estimate of simple linear EV model is studied. It is shown that under some common assumptions of the model, both weak and strong consistency of the estimate are equivalent but it is not so for quadratic-mean consistency. 展开更多
关键词 EV model consistency
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Distributed model predictive control for multiagent systems with improved consistency 被引量:2
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作者 Shanbi WEI Yi CHAI Baocang DING 《控制理论与应用(英文版)》 EI 2010年第1期117-122,共6页
This paper addresses an improved distributed model predictive control (DMPC) scheme for multiagent systems with an attempt to improving its consistency. The deviation between what an agent is actually doing and what... This paper addresses an improved distributed model predictive control (DMPC) scheme for multiagent systems with an attempt to improving its consistency. The deviation between what an agent is actually doing and what its neighbors believe that agent is doing is penalized in the cost function of each agent. At each sampling instant the compatibility constraint of each agent is set tighter than the previous sampling instant. Like the traditional approach, the performance cost is utilized as the Lyapunov function to prove closed-looped stability. The closed-loop stability is guaranteed if the weight matrix for deviation in the cost function are sufficiently large. The proposed distributed control scheme is formulated as quadratic programming with quadratic constraints. A numerical example is given to illustrate the effectiveness of the proposed scheme. 展开更多
关键词 Distributed model predictive control (DMPC) Multiagent systems Compatibility constraint consistency
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Rate of strong consistency of the maximum quasi-likelihood estimator in quasi-likelihood nonlinear models 被引量:2
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作者 XIA Tian KONG Fan-chao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第4期391-400,共10页
Quasi-likelihood nonlinear models (QLNM) include generalized linear models as a special case. Under some regularity conditions, the rate of the strong consistency of the maximum quasi-likelihood estimation (MQLE) ... Quasi-likelihood nonlinear models (QLNM) include generalized linear models as a special case. Under some regularity conditions, the rate of the strong consistency of the maximum quasi-likelihood estimation (MQLE) is obtained in QLNM. In an important case, this rate is O(n-^1/2(loglogn)^1/2), which is just the rate of LIL of partial sums for i.i.d variables, and thus cannot be improved anymore. 展开更多
关键词 maximum quasi-likelihood estimator quasi-likelihood nonlinear models strong consistency
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Consistency Problem with Tracer Advection in the Atmospheric Model GAMIL 被引量:1
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作者 张恺 万慧 +1 位作者 王斌 张美根 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第2期306-318,共13页
The radon transport test, which is a widely used test case for atmospheric transport models, is carried out to evaluate the tracer advection schemes in the Grid-Point Atmospheric Model of IAP-LASG (GAMIL). Two of th... The radon transport test, which is a widely used test case for atmospheric transport models, is carried out to evaluate the tracer advection schemes in the Grid-Point Atmospheric Model of IAP-LASG (GAMIL). Two of the three available schemes in the model are found to be associated with significant biases in the polar regions and in the upper part of the atmosphere, which implies potentially large errors in the simulation of ozone-like tracers. Theoretical analyses show that inconsistency exists between the advection schemes and the discrete continuity equation in the dynamical core of GAMIL and consequently leads to spurious sources and sinks in the tracer transport equation. The impact of this type of inconsistency is demonstrated by idealized tests and identified as the cause of the aforementioned biases. Other potential effects of this inconsistency are also discussed. Results of this study provide some hints for choosing suitable advection schemes in the GAMIL model. At least for the polax-region-concentrated atmospheric components and the closely correlated chemical species, the Flux-Form Semi-Lagrangian advection scheme produces more reasonable simulations of the large-scale transport processes without significantly increasing the computational expense. 展开更多
关键词 numerical climate modelling tracer transport advection scheme consistency
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Thermodynamic Consistency of Plate and Shell Mathematical Models in the Context of Classical and Non-Classical Continuum Mechanics and a Thermodynamically Consistent New Thermoelastic Formulation 被引量:3
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作者 Karan S. Surana Sri Sai Charan Mathi 《American Journal of Computational Mathematics》 2020年第2期167-220,共54页
Inclusion of dissipation and memory mechanisms, non-classical elasticity and thermal effects in the currently used plate/shell mathematical models require that we establish if these mathematical models can be derived ... Inclusion of dissipation and memory mechanisms, non-classical elasticity and thermal effects in the currently used plate/shell mathematical models require that we establish if these mathematical models can be derived using the conservation and balance laws of continuum mechanics in conjunction with the corresponding kinematic assumptions. This is referred to as thermodynamic consistency of the mathematical models. Thermodynamic consistency ensures thermodynamic equilibrium during the evolution of the deformation. When the mathematical models are thermodynamically consistent, the second law of thermodynamics facilitates consistent derivations of constitutive theories in the presence of dissipation and memory mechanisms. This is the main motivation for the work presented in this paper. In the currently used mathematical models for plates/shells based on the assumed kinematic relations, energy functional is constructed over the volume consisting of kinetic energy, strain energy and the potential energy of the loads. The Euler’s equations derived from the first variation of the energy functional for arbitrary length when set to zero yield the mathematical model(s) for the deforming plates/shells. Alternatively, principle of virtual work can also be used to derive the same mathematical model(s). For linear elastic reversible deformation physics with small deformation and small strain, these two approaches, based on energy functional and the principle of virtual work, yield the same mathematical models. These mathematical models hold for reversible mechanical deformation. In this paper, we examine whether the currently used plate/shell mathematical models with the corresponding kinematic assumptions can be derived using the conservation and balance laws of classical or non-classical continuum mechanics. The mathematical models based on Kirchhoff hypothesis (classical plate theory, CPT) and first order shear deformation theory (FSDT) that are representative of most mathematical models for plates/shells are investigated in this paper for their thermodynamic consistency. This is followed by the details of a general and higher order thermodynamically consistent plate/shell thermoelastic mathematical model that is free of a priori consideration of kinematic assumptions and remains valid for very thin as well as thick plates/shells with comprehensive nonlinear constitutive theories based on integrity. Model problem studies are presented for small deformation behavior of linear elastic plates in the absence of thermal effects and the results are compared with CPT and FSDT mathematical models. 展开更多
关键词 Plate and Shell Mathematical models Energy Functional Thermodynamic consistency Classical Continuum Mechanics Non-Classical Continuum Mechanics Internal Rotations Cosserat Rotations Principle of Virtual Work
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3-D consistency dynamic constitutive model of concrete 被引量:4
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作者 Xiao Shiyun,Li Hongnan and Lin Gao School of Hydraulic Engineering,Dalian University of Technology,Dalian 116024,China 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第2期233-246,共14页
Based on the consistency-viscoplastic constitutive model,the static William-Warnke model with three-parameters is modified and a consistency-viscoplastic William-Warnke model with three-parameters is developed that co... Based on the consistency-viscoplastic constitutive model,the static William-Warnke model with three-parameters is modified and a consistency-viscoplastic William-Warnke model with three-parameters is developed that considers the effect of strain rates. Then,the tangent modulus of the consistency viscoplastic model is introduced and an implicit backward Elure iterative algorithm is developed. Comparisons between the numerical simulations and experimental data show that the consistency model properly provides the uniaxial and biaxial dynamic behaviors of concrete. To study the effect of strain rates on the dynamic response of concrete structures,the proposed model is used in the analysis of the dynamic response of a simply-supported beam and the results show that the strain rate has a significant effect on the displacement and stress magnitudes and distributions. Finally,the seismic responses of a 278 m high arch dam are obtained and compared by using the linear elastic model,as well as rate-independent and rate-dependent William-Warnke three-parameter models. The results indicate that the strain rate affects the first principal stresses,and the maximal equivalent viscoplastic strain rate of the arch dam. Numerical calculations and analyses reveal that considering the strain rate is important in the safety assessments of arch dams located in seismically active areas. 展开更多
关键词 CONCRETE strain rate constitutive model consistency-viscoplastic William-Warnke three-parameter model algorithm arch dams seismic responsesimulation
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Locally and globally uniform approximations for ruin probabilities of a nonstandard bidimensional risk model with subexponential claims
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作者 LIU Zai-ming GENG Bing-zhen WANG Shi-jie 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期98-113,共16页
Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair... Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair of the claim-inter-arrival times is arbitrarily dependent.Under some mild conditions,we achieve a locally uniform approximation of the finite-time ruin probability for all time horizon within a finite interval.If we further assume that each pair of the claim-inter-arrival times is negative quadrant dependent and the two classes of claims are consistently-varying-tailed,it shows that the above obtained approximation is also globally uniform for all time horizon within an infinite interval. 展开更多
关键词 bidimensional risk model asymptotic formula subexponential distribution consistently varying tail ruin probability
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Strong Consistency of Estimators of a Semiparametric Regression Model under Fixed Design
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作者 TIAN Ping XUE Liu-gen 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第2期202-209,共8页
In this paper, we consider the following semipaxametric regression model under fixed design: yi = xi′β+g(xi)+ei. The estimators of β, g(·) and σ^2 axe obtained by using the least squares and usual nonp... In this paper, we consider the following semipaxametric regression model under fixed design: yi = xi′β+g(xi)+ei. The estimators of β, g(·) and σ^2 axe obtained by using the least squares and usual nonparametric weight function method and their strong consistency is proved under the suitable conditions. 展开更多
关键词 semiparametric regression model least square estimation weight function strong consistency
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Modeling texture evolution during rolling process of AZ31 magnesium alloy with elasto-plastic self consistent model 被引量:4
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作者 黄诗尧 张少睿 +1 位作者 李大永 彭颖红 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第6期1348-1354,共7页
To gain a better understanding about texture evolution during rolling process of AZ31 alloy, polycrystalline plasticity model was implemented into the explicit FE package, ABAQUS/Explicit by writing a user subroutine ... To gain a better understanding about texture evolution during rolling process of AZ31 alloy, polycrystalline plasticity model was implemented into the explicit FE package, ABAQUS/Explicit by writing a user subroutine VUMAT. For each individual grain in the polycrystalline aggregate, the rate dependent model was adopted to calculate the plastic shear strain increment in combination with the Voce hardening law to describe the hardening response, the lattice reorientation caused by slip and twinning were calculated separately due to their different mechanisms. The elasto-plastic self consistent (EPSC) model was employed to relate the response of individual grain to the response of the polycrystalline aggregate. Rolling processes of AZ31 sheet and as-cast AZ31 alloy were simulated respectively. The predicted texture distributions are in aualitative a^reement with experimental results. 展开更多
关键词 AZ31 alloy texture rolling process elasto-plastic self consistent (EPSC) model
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The Consistency of LSE Estimators in Partial Linear Regression Models under Mixing Random Errors
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作者 Yun Bao YAO Yu Tan LÜ +2 位作者 Chao LU Wei WANG Xue Jun WANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第5期1244-1272,共29页
In this paper,we consider the partial linear regression model y_(i)=x_(i)β^(*)+g(ti)+ε_(i),i=1,2,...,n,where(x_(i),ti)are known fixed design points,g(·)is an unknown function,andβ^(*)is an unknown parameter to... In this paper,we consider the partial linear regression model y_(i)=x_(i)β^(*)+g(ti)+ε_(i),i=1,2,...,n,where(x_(i),ti)are known fixed design points,g(·)is an unknown function,andβ^(*)is an unknown parameter to be estimated,random errorsε_(i)are(α,β)-mix_(i)ng random variables.The p-th(p>1)mean consistency,strong consistency and complete consistency for least squares estimators ofβ^(*)and g(·)are investigated under some mild conditions.In addition,a numerical simulation is carried out to study the finite sample performance of the theoretical results.Finally,a real data analysis is provided to further verify the effect of the model. 展开更多
关键词 β)-mixing random variables partial linear regression model least squares estimator consistency
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Consistency check of degradation mechanism between natural storage and enhancement test for missile servo system 被引量:3
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作者 Wang Xu Sun Quan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第2期415-424,共10页
Reliability enhancement testing(RET) is an accelerated testing which hastens the performance degradation process to surface its inherent defects of design and manufacture. It is an important hypothesis that the degrad... Reliability enhancement testing(RET) is an accelerated testing which hastens the performance degradation process to surface its inherent defects of design and manufacture. It is an important hypothesis that the degradation mechanism of the RET is the same as the one of the normal stress condition. In order to check the consistency of two mechanisms, we conduct two enhancement tests with a missile servo system as an object of the study, and preprocess two sets of test data to establish the accelerated degradation models regarding the temperature change rate that is assumed to be the main applied stress of the servo system during the natural storage. Based on the accelerated degradation models and natural storage profile of the servo system, we provide and demonstrate a procedure to check the consistency of two mechanisms by checking the correlation and difference of two sets of degradation data. The results indicate that the two degradation mechanisms are significantly consistent with each other. 展开更多
关键词 reliability ENHANCEMENT testing (RET) degradation model ACCELERATED equation consistency CHECK Pearson correlation coefficient
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Relativistic Consistent Angular-Momentum Projected Shell-Model:Angular-Momentum Projection 被引量:3
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作者 LIYan-Song LONGGui-Lu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第4期579-582,共4页
The angular-momentum projection part of RECAPS is presented.Application of RECAPS to some deformed nuclei is also presented.
关键词 relativistic consistent angular-momentum projected shell-model angular-momentum projection projected shell model RECAPS-RMF
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Relativistic Consistent Angular-Momentum Projected Shell-Model: Relativistic Mean Field 被引量:3
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作者 LIYan-Song LONGGui-Lu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期429-434,共6页
We develop a relativistic nuclear structure model, relativistic consistent angular-momentum projected shell-model (RECAPS), which combines the relativistic mean-field theory with the angular-momentum projection method... We develop a relativistic nuclear structure model, relativistic consistent angular-momentum projected shell-model (RECAPS), which combines the relativistic mean-field theory with the angular-momentum projection method. In this new model, nuclear ground-state properties are first calculated consistently using relativistic mean-field (RMF) theory. Then angular momentum projection method is used to project out states with good angular momentum from a few important configurations. By diagonalizing the hamiltonian, the energy levels and wave functions are obtained. This model is a new attempt for the understanding of nuclear structure of normal nuclei and for the prediction of nuclear properties of nuclei far from stability. In this paper, we will describe the treatment of the relativistic mean field. A computer code, RECAPS-RMF, is developed. It solves the relativistic mean field with axial-symmetric deformation in the spherical harmonic oscillator basis. Comparisons between our calculations and existing relativistic mean-field calculations are made to test the model. These include the ground-state properties of spherical nuclei <SUP>16</SUP>O and <SUP>208</SUP>Pb, the deformed nucleus <SUP>20</SUP>Ne. Good agreement is obtained. 展开更多
关键词 relativistic consistent angular-momentum projected shell-model relativistic mean field projected shell model PECAPS-RMF
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DISSIPATION-BASED CONSISTENT RATE-DEPENDENT MODEL FOR CONCRETE 被引量:1
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作者 Fei Leng Gao Lin 《Acta Mechanica Solida Sinica》 SCIE EI 2010年第2期147-155,共9页
An energy-dissipation based viscoplastic consistency model is presented to describe the performance of concrete under dynamic loading. The development of plasticity is started with the thermodynamic hypotheses in orde... An energy-dissipation based viscoplastic consistency model is presented to describe the performance of concrete under dynamic loading. The development of plasticity is started with the thermodynamic hypotheses in order that the model may have a sound theoretical background. Independent hardening and softening and the rate dependence of concrete are described separately for tension and compression. A modified implicit backward Euler integration scheme is adopted for the numerical computation. Static and dynamic behavior of the material is illustrated with certain numerical examples at material point level and structural level, and compared with existing experimental data. Results validate the effectiveness of the model. 展开更多
关键词 constitutive model VISCOPLASTICITY consistency model energy dissipation rate dependency CONCRETE backward Euler scheme
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Strong Consistency of Estimators under Missing Responses 被引量:1
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作者 Linran Zhang Jingjing Zhang 《Journal of Applied Mathematics and Physics》 2019年第1期93-103,共11页
In this article, we focus on the semi-parametric error-in-variables model with missing responses: , where yi are the response variables missing at random, are design points, ζi are the potential variables observed wi... In this article, we focus on the semi-parametric error-in-variables model with missing responses: , where yi are the response variables missing at random, are design points, ζi are the potential variables observed with measurement errors μi, the unknown slope parameter &#223;?and nonparametric component g(·) need to be estimated. Here we choose two different approaches to estimate &#223;?and g(·). Under appropriate conditions, we study the strong consistency for the proposed estimators. 展开更多
关键词 SEMI-PARAMETRIC model Error-in-Variables MISSING RESPONSES Strong consistency
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A Novel Unsupervised Change Detection Method with Structure Consistency and GFLICM Based on UAV Images 被引量:2
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作者 Wensong LIU Xinyuan JI +2 位作者 Jie LIU Fengcheng GUO Zongqiao YU 《Journal of Geodesy and Geoinformation Science》 2022年第1期91-102,共12页
With the rapid development of Unmanned Aerial Vehicle(UAV)technology,change detection methods based on UAV images have been extensively studied.However,the imaging of UAV sensors is susceptible to environmental interf... With the rapid development of Unmanned Aerial Vehicle(UAV)technology,change detection methods based on UAV images have been extensively studied.However,the imaging of UAV sensors is susceptible to environmental interference,which leads to great differences of same object between UAV images.Overcoming the discrepancy difference between UAV images is crucial to improving the accuracy of change detection.To address this issue,a novel unsupervised change detection method based on structural consistency and the Generalized Fuzzy Local Information C-means Clustering Model(GFLICM)was proposed in this study.Within this method,the establishment of a graph-based structural consistency measure allowed for the detection of change information by comparing structure similarity between UAV images.The local variation coefficient was introduced and a new fuzzy factor was reconstructed,after which the GFLICM algorithm was used to analyze difference images.Finally,change detection results were analyzed qualitatively and quantitatively.To measure the feasibility and robustness of the proposed method,experiments were conducted using two data sets from the cities of Yangzhou and Nanjing.The experimental results show that the proposed method can improve the overall accuracy of change detection and reduce the false alarm rate when compared with other state-of-the-art change detection methods. 展开更多
关键词 change detection UAV images graph model structural consistency Generalized Fuzzy Local Information C-means Clustering model(GFLICM)
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A case study of the consistency problem in the inverse estimation
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作者 WEI Yanzhou KANG Xianbiao PEI Yuhua 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第9期45-51,共7页
Inverse technique is a widely used method in oceanography, but it has a problem that the retrieved solutions often violate model prior assumptions. To tune the model has consistent solutions, an iteration approach, wh... Inverse technique is a widely used method in oceanography, but it has a problem that the retrieved solutions often violate model prior assumptions. To tune the model has consistent solutions, an iteration approach, which successively utilizes the posterior statistics for next round inverse estimation, is introduced and tested from a real case study. It is found that the consistency may become elusive as the determinants of solution and noise covariance matrices become zero in the iteration process. However, after several steps of such operation, the difference between posterior statistics and the model prior ones can be gradually reduced. 展开更多
关键词 REGULARIZATION consistency inverse problems box inverse model L-curve method
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Novel consistency control strategy for jet dispensing
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作者 SHEN Ping LI Han-xiong 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第6期1418-1436,共19页
A new consistency control method for jet dispensing is proposed. First, the working parameters, namely, viscosity, supply pressure and supply time, are experimentally investigated. Then, the glue viscosity is approxim... A new consistency control method for jet dispensing is proposed. First, the working parameters, namely, viscosity, supply pressure and supply time, are experimentally investigated. Then, the glue viscosity is approximated by a polynomial model using the least square method. Based on this model and temperatme control implemented using the Dahlin principle, the viscosity of the glue can be maintained at a constant value. Then, the viscosity model of the glue is applied to deriving the droplet mass as the nominal model of the temperature controller. The robustness of the temperature controller is analyzed by applying the small gain theory. The glue supply pressure controller is designed using the consistency control strategy, and the robustness is analyzed. Finall), simulations and experiments are conducted using a jet dispensing control system. The results show that the proposed control strategy can significantly improve the droplet consistency. 展开更多
关键词 jet dispensing consistency control internal model control disturbance rejection jetting valve
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Thermodynamically consistent model for diblock copolymer melts coupled with an electric field
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作者 Xiaowen Shen Qi Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第4期710-714,共5页
We present a thermodynamically consistent model for diblock copolymer melts coupled with an electric field derived using the Onsager linear response theory.We compare the model with the thermodynamically inconsistent ... We present a thermodynamically consistent model for diblock copolymer melts coupled with an electric field derived using the Onsager linear response theory.We compare the model with the thermodynamically inconsistent one previously used for the coupled system to highlight their differences in describing transient dynamics. 展开更多
关键词 thermodynamical consistency diblock copolymer melts electric field phase field model
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