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Support vector regression-based internal model control

维普期刊数据库评论

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Journal of Harbin Institute of Technology(New Series) 2007年第3期14卷 411-414页

作者：黄宴委彭铁根 dept.of Automation Shanghai Jiaotong University

This paper proposes a design of internal model control systems for process with delay by using support vector regression(SVR).The proposed system fully uses the excellent nonlinear estimation performance of SVR with the structural risk minimization ***-system stability and steady error are analyzed for the existence of modeling *** simulations show that the proposed control systems have the better control performance than that by neural networks in the cases of the training samples with small size and noises.

关键词： internal model control support vector machine neural networks steady error stability

Probabilistic characterization of cyclic shear modulus reduction for normally to moderately over-consolidated clays

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Earthquake Engineering and Engineering Vibration 2016年第3期15卷 495-508页

作者： Iok-Tong Ng Ka-Veng Yuen Ngai-Kuan Lao dept.of Civil and Environmental Engineering Faculty of Science and Technology University of Macao

Evaluation of the cyclic shear modulus of soils is a crucial but challenging task for many geotechnical earthquake engineering and soil dynamic issues. Improper determination of this property unnecessarily drives up design and maintenance costs or even leads to the construction of unsafe structures. Due to the complexities involved in the direct measurement, empirical curves for estimating the cyclic shear modulus have been commonly adopted in practice for simplicity and economical considerations. However, a systematic and robust approach for formulating a reliable model and empirical curve for cyclic shear modulus prediction for clayey soils is still lacking. In this study, the Bayesian model class selection approach is utilized to identify the most significant soil parameters affecting the normalized cyclic shear modulus and a reliable predictive model for normally to moderately over-consolidated clays is proposed. Results show that the predictability and reliability of the proposed model out performs the well-known empirical models. Finally, a new design chart is established for practical usage.

关键词： Bayesian analysis cyclic shear modulus empirical model geotechnical earthquake engineering normally tomoderately over-consolidated clays

Synthesis and kinetics of 2-chloro-4,6-dinitroresorcinol

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Journal of Harbin Institute of Technology(New Series) 2008年第4期15卷 518-520页

作者：史瑞欣黄玉东 dept.of Chemistry and Chemical Engineering Northeast Forestry University dept.of Applied Chemistry Harbin Institute of Technology

2-chloro-4,6-dinitroresorcinol was synthesized from 4,6-dinitro-1,2,3-trichlorobenzene by *** ultraviolet spectrophotometry was used to measure the absorbency of the hydrolysis mixture under different temperatures and periods of *** kinetic calculation,it is shown that when the reaction temperature is in the range of 343.15 K to 358.15 K,the reaction is consistent with the secondary apparent dynamic model,the apparent activation energy is 200.11 kJ/mol and the expression of kinetic parameter k is 3.761×1028exp(-2.001×105/RT).The reaction is controlled by the course of chemical reactions.

关键词： 2-chloro-4,6-dinitroresorcinol synthesis kinetics

CRACK KINKING IN PIEZOELECTRIC MATERIALS

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Acta Mechanica Sinica 1998年第4期14卷 339-352页

作者：秦庆华 dept.of Mechanical Engineering University of SydneySydneyNSW 2006Australia

The solution for a class of two-dimensional electro- elastic branched crack problems was presented. Explicit Green's function for an interface crack subjected to an edge dislocation was developed using the extended Stroh formulation, which allows the branched crack problem to be expressed in terms of coupled singular integral equations. The kink was modelled as the continuous distribution of edge dislocations and the dislocation density function was defined on the line of the branch crack only. Competition between crack extension along the interface and kinking into the substrate was investigated using the integral equations and the maximum energy release rate criterion. The numerical results have shown the effect of electric field on the path of crack extension. (Edited author abstract) 24 Refs.

关键词： piezoelectric crack fracture dislocation bimaterial

A FAMILY OF MODAL METHODS FOR COMPUTING EIGENVECTOR DERIVATIVES WITH REPEATED ROOTS

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Acta Mechanica Sinica 1996年第2期12卷 158-168页

作者：王文亮 dept.of Appl.Mech. Fudan UniversityShanghai 200433China

A family of modal methods for computing eigenvector derivatives with repeated roots are directly derived from the constraint generalized inverse technique which is originally formulated by Wang and Hu. Extensions are made to Akgun's method to allow treatment of eigensensitivity with repeated roots for general nondefective systems, and Bernard and Bronowicki's modal expansion approach is expanded to a family of modal methods.

关键词： a family of modal methods nondefective system eigenvector derivative eigensensitivity with repeated roots

Advanced in power control for distributed generation system using cooperative algorithms

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Journal of Harbin Institute of Technology(New Series) 2008年第6期15卷 878-883页

作者：王爱华狄建雄陈耀斌 dept.of Electrical and Computer Engineering Purdue University at Indianapolis dept.of Electrical and Automation Engineering Nanjing Institute of Industry Technology

To develop efficient power control strategies for a distributed generation system in order to improve the overall system efficiency, we propose a cooperative algorithm to analyze and design the controller, in which elements of conventional mathematical optimization algorithms are combined with adaptive dynamic elements drawn from intelligent control theory. In our design, the sequential quadratic programming algorithm was first utilized to obtain an optimal solution for power distribution among multiple units. Fuzzy system was then developed to implement the optimal strategies on the basis of optimal solution. In addition, parameters of the fuzzy system were adapted via a genetic algorithm. Tbe simulation results illustrate that the methodology described is useful for a range of control system designs.

关键词： distributed generation power control optimization fuzzy logic genetic algorithm

Optimal design of coordination control strategy for distributed generation system

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Journal of Harbin Institute of Technology(New Series) 2009年第1期16卷 51-56页

作者：王爱华 Norapon Kanjanapadit dept.of Electrical and Computer Engineering Purdue University at Indianapolis dept.of Electrical and Automation Engineering Nanjing Institute of Industry Technology

This paper presents a novel design procedure for optimizing the power distribution strategy in distributed generation system. A coordinating controller, responsible to distribute the total load power request among multiple DG units, is suggested based on the conception of hierarchical control structure in the dynamic system. The optimal control problem was formulated as a nonlinear optimization problem subject to set of constraints. The resulting problem was solved using the Kuhn-Tucker method. Computer simulation results demonstrate that the proposed method can provide better efficiency in terms of reducing total costs compared to existing methods. In addition, the proposed optimal load distribution strategy can be easily implemented in real-time thanks to the simplicity of closed-form solutions.

关键词： distributed generation coordination control strategy Kuhn-Tucker method

Exploring seven hundred years of transhumance, climate dynamic, fire and human activity through a historical mountain pass in central Spain

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Journal of Mountain Science 2016年第7期13卷 1139-1153页

作者： José Antonio LóPEZ-SáEZ Francisca ALBA-SáNCHEZ Sandra ROBLES-LóPEZ Sebastián PéREZ-DíAZ Daniel ABEL-SCHAAD Silvia SABARIEGO-RUIZ Arthur GLAIS Research Group Archaeobiology Institute of History CSIC dept.Botany Faculty of Sciences University of Granada dept.of Plant biology Faculty of Biology Complutense University LETG CAEN GEOPHEN-UMR 6554 CNRS University of Caen-Normandie

A high-altitude peat sequence from the heart of the Spanish Central System(Gredos range) was analysed through a multi-proxy approach to determine the sensitivity of high-mountain habitats to climate, fire and land use changes during the last seven hundred years, providing valuable insight into our understanding of the vegetation history and environmental changes in a mountain pass close to a traditional route of transhumance. The pollen data indicate that the vegetation was dominated by shrublands and grasslands with scattered pines in high-mountain areas, while in the valleys cereals, chestnut and olive trees were cultivated. Strong declines of high-mountain pines percentages are recorded at 1540, 1675, 1765, 1835 and 1925 cal AD, which may be related to increasing grazing activities and/or the occurrence of anthropogenic fires. The practice of mountain summer farming and transhumance deeply changed and redesigned the landscape of the high altitudes in central Spain(Gredos range) since the Middle Ages, although its dynamics was influenced in some way by climate variability of the past seven centuries.

关键词： Climate and human impacts Fire Late Holocene Gredos range Vegetation history

Uncertainty Assessment of Soil Erosion Model Using Particle Filtering

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Journal of Mountain Science 2015年第4期12卷 828-840页

作者： Yeonsu KIM Giha LEE Hyunuk AN Jae E YANG International Water Resources Research Institute Chungnam National University dept.of Construction & Disaster Prevention Eng. Kyungpook National University dept.of Agricultural & Rural Eng. Chungnam National University dept.of Biological Environment Kangwon National University

Recent advances in computer with geographic information system(GIS) technologies have allowed modelers to develop physics-based models for modeling soil erosion processes in time and ***, it has been widely recognized that the effect of uncertainties on model predictions may be more significant when modelers apply such models for their own modeling *** of uncertainty involved in modeling include data, model structural, and parameter *** deal with the uncertain parameters of a catchment-scale soil erosion model(CSEM) and assess simulation uncertainties in soil erosion, particle filtering modeling(PF) is introduced in the *** proposed method, CSEM-PF, estimates parameters of non-linear and non-Gaussian systems, such as a physics-based soil erosion model by assimilating observation data such as discharge and sediment discharge sequences at *** provides timevarying feasible parameter sets as well as uncertainty bounds of outputs while traditional automatic calibration techniques result in a time-invariant global optimal parameter ***-PF was applied to a small mountainous catchment of the Yongdamdam in Korea for soil erosion modeling and uncertainty assessment for three historical typhoon ***, the most optimal parameter sets and uncertainty bounds of simulation of both discharge and sediment discharge at each time step of the study events are provided.

关键词： Data assimilation Particle filter Soil erosion modeling Parameter estimation Time variant parameter Mountainous catchment