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Analysis of mixed model in Gear Transmission Based on ADAMS

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 968-973页

作者： LI Xiufeng WANG Yabin National Key Laboratory on Electromechanical Dynamic Control Beijing Institute of TechnologyBeijing 100081China

The traditional method of mechanical gear driving simulation includes gear pair method and solid to solid contact method. The former has higher solving efficiency but lower results accuracy; the latter usually obtains higher precision of results while the calculation process is complex, also it is not easy to converge. Currently, most of the researches are focused on the description of geometric models and the definition of boundary conditions. However, none of them can solve the problems fundamentally. To improve the simulation efficiency while ensure the results with high accuracy, a mixed model method which uses gear tooth profiles to take the place of the solid gear to simulate gear movement is presented under these circumstances. In the process of modeling, build the solid models of the mechanism in the SolidWorks firstly; Then collect the point coordinates of outline curves of the gear using SolidWorks API and create fit curves in Adams based on the point coordinates; Next, adjust the position of those fitting curves according to the position of the contact area; Finally, define the loading conditions, boundary conditions and simulation parameters. The method provides gear shape information by tooth profile curves; simulates the mesh process through tooth profile curve to curve contact and offer mass as well as inertia data via solid gear models. This simulation process combines the two models to complete the gear driving analysis. In order to verify the validity of the method presented, both theoretical derivation and numerical simulation on a runaway escapement are conducted. The results show that the computational efficiency of the mixed model method is 1.4 times over the traditional method which contains solid to solid contact. Meanwhile, the simulation results are more closely to theoretical calculations. Consequently, mixed model method has a high application value regarding to the study of the dynamics of gear mechanism.

关键词： mixed model contact gear transmission runaway escapement

Strategic Robust mixed model Assembly Line Balancing Based on Scenario Planning

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Tsinghua Science and Technology 2011年第3期16卷 308-314页

作者：徐炜达肖田元 National Laboratory for Information Science and Technology National Computer Integrated Manufacturing Systems Engineering Research CenterDepartment of AutomationTsinghua University

Assembly line balancing involves assigning a series of task elements to uniform sequential stations with certain restrictions. Decision makers often discover that a task assignment which is optimal with respect to a deterministic or stochastic/fuzzy model yields quite poor performance in reality. In real environments, assembly line balancing robustness is a more appropriate decision selection guide. A robust model based on the α worst case scenario is developed to compensate for the drawbacks of traditional robust criteria. A robust genetic algorithm is used to solve the problem. Comprehensive computational experiments to study the effect of the solution procedure show that the model generates more flexible robust solutions. Careful tuning the value of α allows the decision maker to balance robustness and conservativeness of as- sembly line task element assignments.

关键词： mixed model assembly line balancing robust scenario planning genetic algorithm

Numerical Study on the mixed model in the GOCE Polar Gap Problem

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Geo-Spatial Information Science 2011年第3期14卷 216-222页

作者： ZOU Xiancai CAI Jianqing Nico Sneeuw LI Jiancheng Institute of Geodesy University of Stuttgart Geschwister-Scholl-Str. 24D D-70174 Stuttgart Germany School of Geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China

Gravity gradients acquired by the Gravity field and steady-state Ocean Circulation Explorer(GOCE) do not cover the entire earth because of its sun-synchronous orbit leaving data gaps with a radius of about 6.5° in the polar *** studies showed that the loss of data in the polar regions deteriorates the accuracy of the low order(or near zonal) coefficients of the earth gravity model,which is the so-called polar gap problem in *** order to find a stable solution for the earth gravity model from the GOCE gravity gradients,three models,*** Gauss-Markov model,light constraint model and the mixed model,are compared and evaluated numerically with the gravity gradient simulated with the *** comparison shows that the Best Linear Uniformly Unbiased Estimation(BLUUE) estimator of the mixed model can solve the polar gap problem as effectively as the light constraint model;furthermore,the mixed model is more rigorous in dealing with the supplementary information and leads to a better accuracy in determining the global geoid.

关键词： Earth gravity model satellite gravity GOCE mixed model polar gap problem

WOMBAT—A tool for mixed model analyses in quantitative genetics by restricted maximum likelihood (REML)

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第11期8卷 815-821页

作者： MEYER Karin Animal Genetics and Breeding Unit University of New EnglandArmidaleNew South Wales 2351Australia

WOMBAT is a software package for quantitative genetic analyses of continuous traits, fitting a linear, mixed model; estimates of covariance components and the resulting genetic parameters are obtained by restricted maximum likelihood. A wide range of models, comprising numerous traits, multiple fixed and random effects, selected genetic covariance structures, random regression models and reduced rank estimation are accommodated. WOMBAT employs up-to-date numerical and computational methods. Together with the use of efficient compilers, this generates fast executable programs, suitable for large scale analyses. Use of WOMBAT is illustrated for a bivariate analysis. The package consists of the executable program, available for LINUX and WINDOWS environments, manual and a set of worked example, and can be downloaded free of charge from http：//agbu. ***/-kmeyer/***

关键词： Software Variance components Genetic parameters mixed model Restricted maximum likelihood

STUDY ON mixed model OF NEURAL NETWORK FOR FARMLAND FLOOD/DROUGHT PREDICTION

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Acta meteorologica Sinica 1997年第3期11卷 364-373页

作者：金龙罗莹郭光林振山 Jiangsu Meteorological Institute Nanjing 210008 Jiangsu Institute of Climate Application Nanjing 210009 Nanjing Institute of Meteorology Nanjing 210044 Department of Atmospheric Sciences Nanjing UniversityNanjing 210093

The paper concerns a flood/drought prediction model involving the continuation of time series of a predictand and the physical factors influencing the change of *** is made to construct the model by the neural network scheme for the nonlinear mapping relation based on multi-input and single *** model is found of steadily higher predictive accuracy by testing the output from one and multiple stepwise predictions against observations and comparing the results to those from a traditional statistical model.

关键词： flood/drought prediction mixed model nonlinear mapping soil humidity neural network

Combined Selection in Backcross Population of Papaya(Carica papaya L.)by the mixed model Methodology

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American Journal of Plant Sciences 2014年第20期5卷 2973-2983页

作者： Helaine Christine Cancela Ramos Messias Gonzaga Pereira Alexandre Pio Viana Lucas Nunes da Luz Deisy Lucia Cardoso Geraldo Antonio Ferreguetti Laboratory of Plant Breeding Centre for Agricultural Sciences and TechnologyNorth Fluminense State University(UENF)Campos dos GoytacazesBrazil Caliman Agrícola S.A. LinharesBrazil

The selection of superior genotypes based on the simultaneous response to several characteristics of agronomic importance is a key strategy to overcome the scarcity of available varieties of papaya. This study aimed to apply the combined selection by using distinct selection indexes based on both the genetic values obtained by the REML/BLUP methodology and the real measured values to select agronomically superior genotypes of papaya within backcross progenies. The combined selection was carried out based on genetic and phenotypic values, original and standardized, multiplied by the agronomic weights. The results of the analysis of genetic parameters indicate that the evaluated progenies have expressive genetic variability for the considered traits, and that there are real possibilities of genetic progress with the selection. Among the analyzed indexes, the one based on standardized genetic value presented greater consistency in the ranking of genetic material, demonstrating the advantage of data standardization. Five progenies belonging to the BC1 generation, and five to the BC3 generation were selected using this index. A total of 27 plants ag-ronomically superior were selected within the top five progenies and recommended for generation advance, 23 being selected by combined selection and 4 using the direct selection for the four mainly characters in papaya breeding program: production, pulp and fruit firmness and soluble solids. Beyond the selection of superior genotypes for the development of future inbred lines, this study also allowed defining the best strategy to apply the combined selection in papaya using pre-dicted breeding values obtained by BLUP. This strategy may allow higher accuracy in the selection process, thus increasing the chances of success of the breeding programs.

关键词： Papaya Tree Backcross Selection Index mixed model REML/BLUP

A mixed model Analysis of a Fertilizer Experiment on Oil Palm in Nigeria

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Agricultural Sciences 2016年第8期7卷 521-530页

作者： Edwin A. Iguodala Eghwerido Joseph Thomas Austin Edokpayi Obilade Titilola Nigerian Institute for Oil Palm Research Benin City Nigeria Department of Mathematics and Computer Science Federal University of Petroleum Resources Effurun Nigeria Department of Mathematics Obafemi Awolowo University Ile-Ife Nigeria

mixed model analysis procedure was used to analyze the effect of fertilizer application on the Fresh Fruit Bunch (FFB) yield of oil palm. This was with a view to achieve the most appropriate and a robust model for analyzing yield response for fertilizer application in oil palm. In this study, a mixed model analysis procedure was used to analyze yield data obtained from a fertilizer trial conducted between 1997 and 2005. In mixed effect model, replicates and years were used as block. In contrast the fixed effect ANOVA model usually lumped up replicates and years as a random error. In the model replicates were used as block with no block interaction, replicates as block with allowance for block-fertilizer interaction, years as block with allowance for block-fertilizer interaction, and years and replicates as block with allowance for year fertilizer and replicate-fertilizer interaction. mixed model theory was also used to provide the explicit description of the design matrices in the models. Also, hypotheses relevant to each model were formulated and used to test for specific effects in the models such as, fixed part, random part and interacting parts using appropriate error terms as determined by the derived Expected Mean Squares (EMS). The results revealed that at 5% significant level (p

关键词： Fixed model Random model mixed model Oil Palm Fertilizer Trial

Analysis of Variance in an Unbalanced Two-Way mixed Effect Interactive model

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Open Journal of Statistics 2016年第2期6卷 310-319页

作者： F. C. Eze E. U. Nwankwo Department of Statistics Nnamdi-Azikiwe University Awka Nigeria

The expected mean squares for unbalanced mixed effect interactive model were derived using Brute Force Method. From the expected mean squares, there are no obvious denominators for testing for the main effects when the factors are mixed. An expression for F-test for testing for the main effects was derived which was proved to be unbiased.

关键词： mixed model Expected Mean Squares Unbalanced Data

Software applications for providing comprehensive computing capabilities to problems related to mixed models in animal breeding

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华南农业大学学报 2005年第S1期26卷 78-83页

作者： Monchai DAUNGJINDA Department of Animal Science Faculty of AgricultureKhon Kaen University Thailand 40002

Several computer packages have been developed to accomplish improved programs for animal breeding and genetic selection. This paper described most of the currant software and provided suggestions for improved software. Khon Kaen University, Thailand, will provide free of charge the new software developed at Khon Kaen University by the author of this paper. The contact for requesting the software is listed: monchai@***.

关键词： mixed model computer packages animal breeding