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Joint Estimation of State and Parameter with maximum likelihood method 36

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Joint Estimation of State and Parameter with Maximum Likelih...

A laboratory study of directional spectra with maximum likelihood method─I Developing wind wave

第36届中国控制会议

作者： Huiping ZHUANG Jieying Lu Junhui LI School of Automation Science and Engineering South China University of Technology

ISBN: (纸本)9781538629185

Joint estimation of state and parameter is an important branch of adaptive *** paper proposes a combined estimator that simultaneously obtains state and parameter estimation given the scenario where the system is not in canonical *** estimator consists of two *** first part is the combination of Robust Kalman filter and a set of maximum likelihood estimators whose unique goals are to produce parameter *** parameter gained from the first part is then used in a standard Kalman filter in order to generate system state *** computational issues are also *** results show excellent performance of the proposed method.

关键词： joint estimation Robust Kalman filter maximum likelihood method

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Acta Oceanologica Sinica 1999年第1期18卷 59-74页

作者： Zhao Dongliang Masuda Akira Wen Shengchang and Guan Changlong Institute of Physical Oceanography Ocean University of Qingdao Qingdao 266003 China Research Institute for Applied Mechanics Kyushu University Kasuga 816 Japan

From measurements by a circular array consisting of 18 wave gauges in a large wave tank, directional spectra of wind-generated waves in deep water are systematically determined by using maximum likehood *** investigations reveal that the angular spreading of the wave energy is consistent with cos2s(θ/2) proposed by Longuet-Higgins et al. (1963, Ocean Wad Spectra,11~136), if the bimodal distributions of wave energy are not taken into account. Bimodality occurring on higher frequency than peak frequency is too rare to affect our whole results. Surprisingly, a much broader directional spreading than that of the field, which is interpreted by the strongly nonlinear energy transfer because of the very young waves in laboratory, is found. The parameter s depends on frequency in the same way as observed by Mitsuyasu et al. (1975, Journal of Physical Oceanography, 5, 750~760)and Hasselmann et al. (1980, Journal of physical Oceanography, 10, 1264~1280) in the field, and the relationship between the four nondimensional parameters sm, fo, b1 and b2, determining the directional width, and (corresponding to the inverse of wave age) are given respectively. The observed distributions are found to agree well with the suggestion of Donelan et al. (1985, Philosophical Transaction of Royal Society of London, A315, 509~562) when applied to field waves.

关键词： Directional spectrum maximum likelihood method wind wave

A Comparative Study of Supervised Classification methods for Investigating Landslide Evolution in the Mianyuan River Basin,China

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Journal of Earth Science 2023年第2期34卷 316-329页

作者： Yujie Long Weile Li Runqiu Huang Qiang Xu Bin Yu Gang Liu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China Sichuan Metallurgical Geological Survey and Design Group Co. LtdChengdu 610081China College of Earth Sciences Chengdu University of TechnologyChengdu 610059China

The Ms8.0 Wenchuan earthquake of 2008 dramatically changed the terrain surface and caused long-term increases in the scale and frequency of landslides and debris *** changing trend of landslides in the earthquake-affected area over the decade since the earthquake remains largely *** this study,we were able to address this issue using supervised classification methods and multitemporal remote sensing images to study landslide evolution in the worst-affected area(Mianyuan River Basin)over a period of ten *** images were processed using the maximum likelihood method and random forest algorithm to automatically map landslide occurrence from 2007 to *** principal findings are as follows:(1)when compared with visual image analysis,the random forest algorithm had a good average accuracy rate of 87%for landslide identification;(2)postevent landslide occurrence has generally decreased with time,but heavy monsoonal seasons have caused temporary spikes in activity;and(3)the postearthquake landslide activity in the Mianyuan River Basin can be divided into a strong activity period(2008 to 2011),medium activity period(2012 to 2016),and weak activity period(post 2017).Landslide activity remains above the prequake level,with damaging events being rare but continuing to ***-term remote sensing and on-site monitoring are required to understand the evolution of landslide activity after strong earthquakes.

关键词： Wenchuan earthquake Mianyuan River Basin automatic detection evolutionary trend maximum likelihood method random forest algorithm engineering geology

Determining capacity of multimodal multi-commodities freight transportation network from critical link volumes

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Journal of Beijing Institute of Technology 2012年第4期21卷 492-497页

作者：许旺土 School of Architecture and Civil Engineering Xiamen University

The commodity transportation capacity between all origin-destination （ OD ） pairs over the multimodal multi-commodities freight transportation network （MMFTN） is determined. A multi-ob- jectives mathematical model is formulated for determining the OD capacity over the MMFTN accord- ing to a transporting capacity matrix that increased from the reference matrixes. The corresponding incremental factor for estimating the capacity matrix is obtained via the maximal likelihood estima- tion method that samples data of differences between the estimated commodity volumes and carrying capacities of the critical links. The proposed formulations are tested by an experimental highway and railroad freight transportation network in an existing literature. The relevant results of OD capacities are displayed and applicability of the algorithm is certified.

关键词： network capacity multimodal multi-commodities transportation origin-destination(OD) matrix estimation critical links incremental factor maximum likelihood method

A laboratory study of directional spectrawith maximum likelihood mehod─ⅡDecaying swell

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Acta Oceanologica Sinica 1999年第1期18卷 75-85页

From measurements by a circular array consisting of 18 wave gauges in a large wave tank, directional spectra of swell in deep water are systematically investigated with maximum likelihood method. It is shown that the directional spreading of swell, qualitatively similar to that of developing wind wave which is narrowest in the region of Peak frequency and bxoadens with increasing or decreasing frequency, can be effectively described by cos2s(θ/2) introduced by Longuet-Higgins et al. (1963,Ocean Wave Spectra, 111~136). It is intriguing that bimodal distribution found in our experiments appers at the forward face instead of the rear face of a frequency spectrum in the cases of nonlinearity being very weak. Parameterized by nonlinearity, formulations which can be applied to swell as well as wind wave are proposed. It is concluded that nonlinear interaction plays a central role in controlling the development of directional angular spreading even for the swell.

关键词： Directional spectrum maximum likelihood method swell wind wave

Advances on methods for mapping QTL in plant

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Science Bulletin 2006年第23期51卷 2809-2818页

作者： ZHANG Yuan-Ming Section on Statistical Genomics, State Key Laboratory of Crop Genetics and Germplasm Enhancement/National Center for Soybean Improvement, College of Agriculture, Nanjing Agricultural University, Nanjing 210095, China Section on Statistical Genomics State Key Laboratory of Crop Genetics and Germplasm Enhancement/National Center for Soybean Improvement College of Agriculture Nanjing Agricultural University Nanjing China

Advances on methods for mapping quantitative trait loci (QTL) are firstly summarized. Then, some new methods, including mapping multiple QTL, fine mapping of QTL, and mapping QTL for dynamic traits, are mainly described. Finally, some future prospects are proposed, including how to dig novel genes in the germplasm resource, map expression QTL (eQTL) by the use of all markers, phenotypes and micro-array data, identify QTL using genetic mating designs and detect viability loci. The purpose is to direct plant geneticists to choose a suitable method in the inheritance analysis of quantitative trait and in search of novel genes in germplasm resource so that more potential genetic information can be uncovered.

关键词： quantitative trait locus parameter estimation effect maximum likelihood method Bayesian method.

Adaptive Evolution of cry Genes in Bacillus thuringiensis:Implications for Their Specificity Determination

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Genomics, Proteomics & Bioinformatics 2007年第2期5卷 102-110页

作者： Jin-Yu Wu Fang-Qing Zhao Jie Bai Gang Deng Song Qin Qi-Yu Bao Institute of Biomedical Informatics Wenzhou Medical College Wenzhou 325000 China Insititute of Oceanology Chinese Academy of Sciences Qingdao 266071 China.

The cry gene family, produced during the late exponential phase of growth in Bacillus thuringiensis, is a large, still-growing family of homologous genes, in which each gene encodes a protein with strong specific activity against only one or a few insect species. Extensive studies are mostly focusing on the structural and functional relationships of Cry proteins, and have revealed several residues or domains that are important for the target recognition and receptor attachment. In this study, we have employed a maximum likelihood method to detect evidence of adaptive evolution in Cry proteins, and have identified 24 positively selected residues, which are all located in Domain Ⅱ or Ⅲ. Combined with known data from mutagenesis studies, the majority of these residues, at the molecular level, contribute much to the insect specificity determination. We postulate that the potential pressures driving the diversification of Cry proteins may be in an attempt to adapt for the ＂arm race＂ between δ-endotoxins and the targeted insects, or to enlarge their target spectra, hence result in the functional divergence. The sites identified to be under positive selection would provide targets for further structural and functional analyses on Cry proteins.

关键词： adaptive evolution Bacillus thuringiensis Cry protein maximum likelihood method

Power Hamza Distribution with Application to Lifetime Data

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Journal of Applied Mathematics and Physics 2022年第1期10卷 31-48页

作者： Samuel U. Enogwe Chike H. Nwankwo Eric U. Oti Department of Statistics Michael Okpara University of Agriculture Umudike Nigeria Department of Statistics Nnamdi Azikiwe University Awka Nigeria Department of Statistics Federal Polytechnic Ekowe Nigeria

In this paper, a three-parameter lifetime distribution named power Hamza distribution (PH) is proposed. The PH distribution is a useful generalization of the Hamza distribution which accommodates heavy-tailed, upside-down bathtub and J-shaped hazard rates making it more flexible than the Hamza distribution for modelling various kinds of lifetime data. A comprehensive account of the properties of this distribution is presented. The maximum likelihood estimators of the unknown model parameters are discussed. Finally, a real-life data is analyzed for illustrative purpose proving that the PH outperforms the Hamza distribution and several other lifetime distributions.

关键词： Hamza Distribution Hazard Rate Function Conditional Moments Stochastic Ordering maximum likelihood method

ON THE TESTING FOR ALPHA-STABLE DISTRIBUTIONS OF ETHERNET NETWORK TRAFFIC

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Journal of Electronics(China) 2003年第4期20卷 309-312页

作者： Ge Xiaohu Zhu Guanxi Zhu Yaoting (Electron. & Info. Eng. Dept., Huazhong Univ. of Sci. & Tech., Wuhan 430074) Electron. & Info. Eng. Dept. Huazhong Univ. of Sci. & Tech. Wuhan

The modeling of network traffic is important for the design and application of networks, but little is known as to the characteristics of distribution of packets in network traffic. In this letter the distribution of ... 详细信息

关键词： Alpha-stable distributions Self-similar maximum likelihood method Network traffic