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Advances in estimation methods of Surface Solar Radiation

Journal of Landscape Research 2016年第5期8卷 81-84页

作者： GUO Peng WU Fadong XU Liping School of Earth Sciences and Resources China University of Geosciences (Beijing) College of Sciences Shihezi University

Based on the main research results of estimation methods of surface solar radiation at home and abroad in recent decades, three commonly used estimation models of surface solar radiation have been introduced, and their principles, advantages and disadvantages have been analyzed to provide scientific references for further study of surface solar radiation in future.

关键词： Surface solar radiation estimation methods Advances

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Joint parameter and state estimation for stochastic uncertain system with multivariate skew t noises

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Chinese Journal of Aeronautics 2022年第5期35卷 69-86页

作者： Shuhui LI Zhihong DENG Xiaoxue FENG Ruxuan HE Feng PAN School of Automation Beijing Institute of TechnologyBeijing 100081China Kunming-BIT Industry Technology Research Institute INC Kunming 650106China

Due to the pulse interference, measurement outliers and artificial modeling errors, the multivariate skew t noise widely exists in the real environment. However, to date, little attention has been paid to the state estimation for systems in which the process noise and the measurement noise are both modeled as the heavy-tailed and skew non-Gaussian noise. In this paper, the multivariate skew t distribution is utilized to model the heavy-tailed and skew non-Gaussian noise. Then a probabilistic graphical form of the multivariate skew t distribution is given and proved. Based on the probabilistic graphical form, a hierarchical Gaussian state space model for stochastic uncertain systems is proposed, which transforms the estimation problem for systems with the heavy-tailed and skew non-Gaussian noises into the one with a hierarchical Gaussian state space model. Next, given the designed Gaussian state space model, the robust Bayesian filter and smoother based on the variational Bayesian inference are proposed to approximately estimate the system state and the unknown noise parameters. Furthermore, the complexity analysis together with the controllability and observability for stochastic uncertain systems with multivariate skew t noises is given. Finally,the simulation results of the target tracking scenario verify the validity of the proposed algorithms.

关键词： estimation methods Non-Gaussian noise Target tracking Uncertain systems Variational principles

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Evaluating multispecies survey designs using a joint species distribution model

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Aquaculture and Fisheries 2020年第3期5卷 156-162页

作者： Chongliang Zhang Binduo Xu Ying Xue Yiping Ren College of Fisheries Ocean University of China.216Fisheries Hall5 Yushan RoadQingdao266003China Qingdao National Laboratory for Marine Science and Technology 1 Wenhai RoadQingdao266000China

Survey designs should be efficient as marine survey programs are usually expensive and time-consuming;however,surveys have rarely been evaluated for multiple *** the present study,we evaluated multispecies fisheries surveys with respect to three influential factors,i.e.,sampling methods,estimation methods and sample size.A joint species distribution model(JSDM)developed in north Yellow Sea,China was used as the operating model to simulate the spatial distribution of multiple species *** examined the precision of multispecies abundance estimation using diverse sampling methods[random sampling(RDS),systematic sampling(SYS),stratified random sampling(SRS),generalized random-tessellation stratified sampling(GRT)and spatial coverage sampling(SPC)],estimation methods[arithmetic mean(Arm),universal kriging(Ukr),multivariate distribution model(Mvd),and boral model(Brm)],and a range of sample sizes(from 30 to 300).The results showed significant differences in estimation among sampling methods,where GRT and SYS yielded less relative absolute bias(RAB)over all and RDS showed the least *** estimation methods,Mvd and Arm showed the best performances and Brm yielded the least *** interactions existed between sampling and estimation *** worked best with GRT,likewise Mvd with SYS and Ukr with *** and Mvd showed the best performances for a small sample size(N=30),and all sampling and estimation methods provided similar results for a large sample size(N=300).Generally,doubling sample size resulted in a decrease of RAB by 0.097 on average,a rate depending on species,sampling and estimation *** study contributed to an integrative framework for evaluating designs of multispecies fisheries surveys.

关键词： Multispecies survey Boral Sampling methods estimation methods Sample size

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A systematic review of research studies on the estimation of net primary productivity in the Three-River Headwater Region, China

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Journal of Geographical Sciences 2017年第2期27卷 161-182页

作者： SUN Qingling LI Baolin ZHOU Chenghu LI Fei ZHANG Zhijun DING Lingling ZHANG Tao XU Lili State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciencesand Natural Resources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023 China Remote Sensing Monitoring Center of Qinghai Ecology and Environment Xining 810007 China

The Three-River Headwater Region（TRHR）, known as the ＂Water Tower of China＂, is an important ecological shelter for national security interests and regional sustainable development activities for many downstream regions in China and a number of Southeast Asian countries. The TRHR is a high-elevation, cold environment with a unique, but typical alpine vegetation system. Net primary productivity（NPP） is a key vegetation parameter and ecological indicator that can reflect both natural environmental changes and carbon budget levels. Given the unique geographical environment and strategic location of the TRHR, many scholars have estimated NPP of the TRHR by using different methods; however, these estimates vary greatly for a number of reasons. To date, there is no paper that has reviewed and assessed NPP estimation studies conducted in the TRHR. Therefore, in this paper, we（1） summarized the related methods and results of NPP estimation in the TRHR in a systematic review of previous research;（2） discussed the suitability of existing methods for estimating NPP in the TRHR and highlighted the most significant challenges; and（3） assessed the estimated NPP results. Finally, developmental directions of NPP estimation in the TRHR were prospected.

关键词： Three-River Headwater Region(TRHR) net primary productivity(NPP) estimation methods NPP models ecological parameters

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Measuring Herbage Mass by Non-Destructive methods： A Review

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Journal of Agricultural Science and Technology(A) 2011年第3X期1卷 303-314页

作者： J. E. Lopez-Diaz A. I. Roca-Fernaindez Gonzalez-Rodriguez Agrarian Research Centre of Mabegondo P.O. Box 10 15080 La Coruna Spain

Accurate assessment of herbage mass （HM） in pasture is a key to budgeting forage in grazing systems worldwide. Different non-destructive techniques to measuring pasture yield are commented. The methods compared include visual estimations, manual and electronic pasture meters and remote sensing. All methods are associated with a moderate to high error, showing that some indirect methods of yield estimation are appropriate under most appropriate because many factors as climate variations, soil certain conditions. In general terms, no method was found as the characteristics, plant phenology, pasture management and species composition must be taken into account to make local calibrations from a general model. Best results were found modifying general methods under local calibrations and under local conditions. In order to give farmers the best method to manage adequately their own grazing systems, researchers must select the most suitable technique considering the scale of operation, the desired accuracy and the resources available.

关键词： Forage mass estimation methods pasture yield non-destructive measuring.

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中国消费、劳动和资本收入有效税率估算研究

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财政与税务 2015年第4期 3-12页

作者：梁红梅张卫峰

笔者以Mendoza et al(1994)[1]的平均有效税率法为理论基础，采用新的税种分摊方法估算了1985-2012年间中国消费、劳动和资本收入有效税率变动情况。估算结果表明：第一，我国消费、劳动和资本收入有效税率差距显著，资本收入有效税率... 详细信息

笔者以Mendoza et al(1994)[1]的平均有效税率法为理论基础，采用新的税种分摊方法估算了1985-2012年间中国消费、劳动和资本收入有效税率变动情况。估算结果表明：第一，我国消费、劳动和资本收入有效税率差距显著，资本收入有效税率最高，劳动收入有效税率最低。第二，近年来我国城乡居民消费支出有效税率差距日趋缩小，现已基本持平，表明城乡居民消费结构正逐渐趋同。第三，我国城乡居民劳动收入有效税率差距较大，劳动税负主要集中于城镇居民。

关键词：有效税率估算方法中国经验 Effective tax rates estimation methods Chinese experience

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要素替代弹性估计方法的比较与改进

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统计与精算 2021年第4期

作者：封永刚蒋雨彤

研究目标：筛选出要素替代弹性的最优估计方法，并对其进行改进，实现要素替代弹性由静态估计到动态估计的跨越。研究方法：从可扩展性、参数识别的全面性及可靠性三个维度，对三种估计方法的优缺点进行比较分析；以估计1978～2017年中... 详细信息

研究目标：筛选出要素替代弹性的最优估计方法，并对其进行改进，实现要素替代弹性由静态估计到动态估计的跨越。研究方法：从可扩展性、参数识别的全面性及可靠性三个维度，对三种估计方法的优缺点进行比较分析；以估计1978～2017年中国的要素替代弹性为例，通过实证检验完成最优估计方法的判定，并借鉴数据包络分析的窗式移动思想，进行最优方法的动态改进。研究发现：最优一阶条件法和Kmenta级数展开法存在可扩展性较差、参数识别不全面、多重共线性严重、估计结论前后矛盾等问题；标准化供给面系统方法的灵活性、准确性与可靠性更高，在动态改进后仍然能够实现要素替代弹性的有效估计。研究创新：在完全与非完全竞争市场假设、技术进步率不变与可变框架下，对要素替代弹性估计方法的优缺点进行全面的实证检验，并创新性地提出一种窗式动态估计的改进思路，解决要素替代弹性的动态估计难题。研究价值：消除现有研究的要素替代弹性估计争论，促进要素替代弹性的准确识别，为要素替代弹性的经济意义分析提供坚实保障。

关键词：替代弹性估计方法动态估计 elasticity of substitution estimation methods dynamic estimation

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