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Journal of China Textile University(English Edition) 1999年第4期16卷 13-16页

作者：吴国海华建兴

A novel approach to design Internal Model Controller(IMC)is proposed in this paper directly from measuredinput and output plant data,which are assumed to becontaminated by measurement noise.In order to avoidthe complicated structure-identification problem inmost cases,two Finite Impulse Response(FIR)modelsare taken to represent the plant model and the internalmodel controller respectively.Taking account of mea-surement noise both in the plant input and its output,anESD based Total Least squares(TLS)solution is appliedfor the unbiased identification of the plant model and itsinverse model,the latter constitutes the internal modelcontroller according to the principle that the internalmodel controller approximates the inverse dynamics ofthe plant model.Simulations are given for a testifica-tion.

关键词： Internal model control total least squares eigen - space decomposition parameter estimation identification

Oblique Wave Trapping by Vertical Permeable Membrane Barriers Located near a Wall

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Journal of Marine Science and Application 2017年第4期16卷 490-501页

作者： Santanu Koley Trilochan Sahoo Dhirubhai Ambani Institute of Information and Communication Technology Gandhinagar - 382007 India Department of Ocean Engineering and Naval Architecture Indian Institute of Technology Kharagpur - 721302 India

The effectiveness of a vertical partial flexible porous membrane wave barrier located near a rigid vertical impermeable seawall for trapping obliquely incident surface gravity waves are analyzed in water of uniform depth under the assumption of linear water wave theory and small amplitude membrane barrier response. From the general formulation of the submerged membrane barrier, results for bottom-standing and surface-piercing barriers are computed and analyzed in special cases. Using the eigenfunction expansion method, the boundary-value problems are converted into series relations and then the required unknowns are obtained using the least squares approximation method. Various physical quantities of interests like reflection coefficient, wave energy dissipation, wave forces acting on the membrane barrier and the seawall are computed and analyzed for different values of the wave and structural parameters. The study will be useful in the design of the membrane wave barrier for the creation of tranquility zone in the lee side of the barrier to protect the seawall.

关键词： surface waves flexible membrane porosity eigenfunction expansion least squares approximation

Study on the Improvement Strategies of Physical Environment for Square in Severe Cold Regions' Rural Areas

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Journal of Harbin Institute of Technology(New Series) 2014年第4期21卷 18-23页

作者： Xin-Yu Zhang Hong Jin School of Architecture Harbin Institute of Technology School of Architecture Harbin Institute of Technology

To improve the comfortable physical environment for square in severe cold regions' rural areas. This paper applies the methods of questionnaires,field testing and statistical analysis to compare and analyze two different square cases of Qingyunpu in Liaoning Province,and conclude the main factors which affect the physical environmental comfort. The improvement strategies for physical environment of rural square are put forward from the aspects of site selection,road position,orientation,landscape design,and ground pavement material selection,aiming to provide the design basis for the physical environment of square in severe cold regions' rural areas.

关键词： rural areas of severe cold regions squares physical environment improvement strategies

A new method of identifying and locating gross errors——Quasi-accurate detection

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Chinese Science Bulletin 1999年第23期44卷 2200-2204页

作者： OU JikunInstitute of Geodesy and Geophysics , IMboratory of Dynamical Geodesy , Chinese Academy of Sciences , Wuhan 430077 , China Institute of Geodesy and Geophysics Laboratory of Dynamical Geodesy Chinese Academy of Sciences Wuhan 430077 China

A new idea and a distinctive method have been proposed, which concern real errors and their estimators. By using the idea of 'Quasi-Stable Adjustment' created by Prof. Zhou Jiangwen for reference, the rank-deficient equations on real errors are resolved by adding the conditions under which the minimum of the norm of the real errors of the quasi-accurate observations is restrained.

关键词： least squares (LS) detection of gross errors (or outliers) hypothesis test robust estimation real errors.

Some Results on Parameter Estimation in Linear Models With Prior Information

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Chinese Science Bulletin 1993年第16期38卷 1321-1324页

作者：吴启光臧传博 Institute of Systems Science Academia Sinica

Consider the linear model Y=Xβ+e; e～N(0, σ~2I). (1) where X is a known n×p matrix of rank p0 are parameters. Assume that prior information about β in the form U=Hβ+ε (2) is available. Here H is a known k×p mat... 详细信息

关键词： mixed regression estimator least squares estimator uniformly minimum risk unbiased estimator minimax estimator

Necessary and Sufficient Conditions for the Existence of UMRU Estimators in Growth Curve Model

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Chinese Science Bulletin 1994年第2期39卷 89-92页

作者：吴启光 Institute of Systems Science Academia Sinica Beijing 100080 PRC

Throughout this note, the following notations are used. For matrices A and B,A>B means that A-B is positive definite symmetric, A×B denotes the Kroneckerproduct of A and B R（A）, A’ and A- stand for the column space, the transpose andany g-inverse of A, respectively; PA=A（A’A）-A’;for s×t matrix B=（b1…bt）,vec（B） de-notes the st-dimensional vector （b1′b2′…bt′）′, trA stands for the trace of the square ma-trix A.

关键词： convex loss function least squares estimator uniformly minimum risk unbiased (UMRU) estimator uni-form covariance structure serial covariance structure.

SOLUTION OF THE RADIAL EQUATION FOR THE RELATIVE MOTION OF A DIATOMIC MOLECULE

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Chinese Science Bulletin 1990年第22期35卷 1891-1894页

作者：方建云 Institute of Theoretical Chemistry Jilin University Changchun 130023 PRC

Ⅰ. RADIAL EQUATIONFor the nuclear motion of a diatomic molecule, the radial equation, after separating the translational motion of the mass center and the angular part, can be written

关键词： radial equation harmonic oscillator basis function least squares fitting recursion expansion.

QRD-BASED MULTICHANNEL ADAPTIVE LATTICEALGORITHMS FOR THE PARAMETERIDENTIFICATION PROBLEM

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Journal of Electronics(China) 1996年第3期13卷 201-210页

作者： Ouyang Shan Fang Huijun(Guilin Institute of EJectronic TechnoJogy, Guilin 541004) Guilin Institute of Electronic Technology Guilin

A pair of multichannel recursive least squares (RLS) adaptive lattice algorithms based on the order recursive of lattice filters and the superior numerical properties of Givens algorithms is derived in this paper. The derivation of the first algorithm is based on QR decomposition of the input data matrix directly, and the Givens rotations approach is used to compute the QR decomposition. Using first a prerotation of the input data matrix and then a repetition of the single channel Givens lattice algorithm, the second algorithm can be obtained. Both algorithms have superior numerical properties, particularly the robustness to wordlength limitations. The parameter vector to be estimated can be extracted directly from internal variables in the present algorithms without a backsolve operation with an extra triangular array. The results of computer simulation of the parameter identification of a two-channel system are presented to confirm efficiently the derivation.

关键词： Recursive least squares lattice algorithm QR decomposition Multichannel signals Adaptive parameter identification

Forecasting using supervised factor models

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Journal of Management Science and Engineering 2019年第1期4卷 12-27页

作者： Yundong Tu Tae-Hwy Lee Guanghua School of Management and Center for Statistical Science Peking UniversityBeijing100871China Department of Economics University of CaliforniaRiversideCA92521USA

This paper examines the theoretical and empirical properties of a supervised factor model based on combining forecasts using principal components(CFPC),in comparison with two other supervised factor models(partial least squares regression,PLS,and principal covariate regression,PCovR)and with the unsupervised principal component regression,PCR.The supervision refers to training the predictors for a variable to forecast.We compare the performance of the three supervised factor models and the unsupervised factor model in forecasting of U.S.CPI inflation.The main finding is that the predictive ability of the supervised factor models is much better than the unsupervised factor model.The computation of the factors can be doubly supervised together with variable selection,which can further improve the forecasting performance of the supervised factor models.Among the three supervised factor models,the CFPC best performs and is also most stable.While PCovR also performs well and is stable,the performance of PLS is less stable over different out-of-sample forecasting periods.The effect of supervision gets even larger as forecast horizon increases.Supervision helps to reduce the number of factors and lags needed in modelling economic structure,achieving more parsimony.

关键词： Combining forecasts Principal components Supervision matrix Fixed point Principal covariate regression Partial least squares

Parameter Estimation for Complex Ornstein-Uhlenbeck Processes

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Journal of Donghua University(English Edition) 2019年第4期36卷 399-404页

作者：潘玉荣孙西超 College of Science Bengbu University

The drift parameter estimation problem of the complex Ornstein-Uhlenbeck process driven by a complexα-stable motion is considered.Based on discrete observations,an estimator of the unknown drift parameter is constructed by using the least squares method.Moreover,the strong consistency and the asymptotic distribution of the least squares estimator are derived under some assumptions.

关键词： α-stable motion complex Ornstein-Uhlenbeck processes the least squares estimation consistency asymptotic distribution