Combined state and parameter estimation for a bilinear state space system with moving average noise     

Xiao Zhang  Ling Xu  Feng Ding  Tasawar Hayat 《Journal of The Franklin Institute》2018,355(6):3079-3103

This paper considers the identification problem of bilinear systems with measurement noise in the form of the moving average model. In particular, we present an interactive estimation algorithm for unmeasurable states and parameters based on the hierarchical identification principle. For unknown states, we formulate a novel bilinear state observer from input-output measurements using the Kalman filter. Then a bilinear state observer based multi-innovation extended stochastic gradient (BSO-MI-ESG) algorithm is proposed to estimate the unknown system parameters. A linear filter is utilized to improve the parameter estimation accuracy and a filtering based BSO-MI-ESG algorithm is presented using the data filtering technique. In the numerical example, we illustrate the effectiveness of the proposed identification methods.  相似文献   

跨域环境治理的多元主体共建共享机制     

褚义景  .戴胜利 《科技管理研究》2019,(21)

跨域环境治理领域内的多元主体共建共享机制能否以及如何构建是一个备受关注的话题。文章在审视跨域环境治理特性的基础上，回答了为什么要构建多元主体共建共享机制的问题；根据过程分析理论的有关结论，解析跨域环境治理的流程与环节，回应了如何构建多元主体共建共享机制的问题。文章认为，通过多元主体共建共享机制的设计，达成政府、市场、社会团体和公众在内的多元主体合作共治，是实现区域环境公共利益最大化的重要途径。  相似文献   

Soft sensor modeling with a selective updating strategy for Gaussian process regression based on probabilistic principle component analysis     

Weili Xiong  Xudong Shi 《Journal of The Franklin Institute》2018,355(12):5336-5349

Considering the deviation of the working condition and the high updating frequency of the traditional moving window methods, this paper proposes a selective strategy of moving window for the Gaussian process regression in the latent probabilistic component space. First, the probabilistic principle component analysis (PPCA) is employed to deal with the multi-dimensional issue and extract essential information of the process data. Because the latent probabilistic components are more sensitive to the deviation of the working condition in the industrial process than the original data, the regression performance is improved under the PPCA framework. Under the proposed strategy, the soft sensor is able to detect the change of the working condition, and the updating is activated only when the predicted error exceeds the preset threshold, otherwise the model is kept unchanged. Furthermore, the promotion of both predicted accuracy and efficiency can be obtained by regulating the threshold. To test the effectiveness of the proposed method, a wastewater case study is provided, and the result shows that the proposed strategy works better under the probabilistic than other conventional methods.  相似文献   

Understanding the topic evolution of scientific literatures like an evolving city: Using Google Word2Vec model and spatial autocorrelation analysis     

Kai Hu  Qing Luo  Kunlun Qi  Siluo Yang  Jin Mao  Xiaokang Fu  Jie Zheng  Huayi Wu  Ya Guo  Qibing Zhu 《Information processing & management》2019,56(4):1185-1203

Topic evolution has been described by many approaches from a macro level to a detail level, by extracting topic dynamics from text in literature and other media types. However, why the evolution happens is less studied. In this paper, we focus on whether and how the keyword semantics can invoke or affect the topic evolution. We assume that the semantic relatedness among the keywords can affect topic popularity during literature surveying and citing process, thus invoking evolution. However, the assumption is needed to be confirmed in an approach that fully considers the semantic interactions among topics. Traditional topic evolution analyses in scientometric domains cannot provide such support because of using limited semantic meanings. To address this problem, we apply the Google Word2Vec, a deep learning language model, to enhance the keywords with more complete semantic information. We further develop the semantic space as an urban geographic space. We analyze the topic evolution geographically using the measures of spatial autocorrelation, as if keywords are the changing lands in an evolving city. The keyword citations (keyword citation counts one when the paper containing this keyword obtains a citation) are used as an indicator of keyword popularity. Using the bibliographical datasets of the geographical natural hazard field, experimental results demonstrate that in some local areas, the popularity of keywords is affecting that of the surrounding keywords. However, there are no significant impacts on the evolution of all keywords. The spatial autocorrelation analysis identifies the interaction patterns (including High-High leading, High-Low suppressing) among the keywords in local areas. This approach can be regarded as an analyzing framework borrowed from geospatial modeling. Moreover, the prediction results in local areas are demonstrated to be more accurate if considering the spatial autocorrelations.  相似文献   

空间解析几何教学改革初探与实践     

杨勇歌  孙亚辉  陈学松 《教育教学论坛》2020,(20):297-298

空间解析几何是大学数学类专业的一门重要基础课,也是数学专业学生深入学习几何学专业知识的基础课程。本文通过在课堂中引入雨课堂、数学史和MATLAB,提高了学生的学习效率。  相似文献   

山东半岛国家自主创新示范区创新能力研究   总被引：1，自引：0，他引：1  

刘文  杨馥萍 《科技管理研究》2018,(10)

山东半岛国家自主创新示范区是我国首个以海洋经济为特色的国家高新技术示范区,基于示范区的战略定位和区域特点,选取创新支撑能力、自主创新能力、产业集群与国际化3个目标层领域7个准则层因素共24个指标层指标,对示范区内6个高新区的创新能力进行评价。从总体创新水平来看,青岛市科技创新水平的发展较为成熟,处于6市首位,其次是济南,接下来是潍坊、淄博、烟台、威海。示范区内各地应以涉海高新技术产业为重点,汇集区域优势资源,实现六大高新区产业协同、错位发展,从而提高示范区的整体创新能力。  相似文献   

生命中不可承受之轻与重--史铁生创作中的生死主题浅析   总被引：1，自引：0，他引：1  

罗云锋 《哈尔滨学院学报》2003,24(11):95-101

在史铁生的全部创作中，生与死、命运与人生的思考一以贯之。本文通过对史铁生作品的文本细读和分析，揭示出作家通过文本所呈现出来的对生死的深刻思考和体悟。史铁生作品中对死亡似乎存在着颇为矛盾的两种态度，存在着一个难解的悖论：一方面是对死亡的恐惧和千方百计的选避。另一方面却是对死感到无比的亲切并以死作为无上的福祉；而“生”在史铁生的作品中既是荒诞、偶然、宿命，是不可克服的人类困境，更意味着一种过程，意味着认真地执著于活着而超越生死!于是，人在生与死之间进行着痛苦的拉锯战和艰难的抉择，认真地体验着生命中不可承受之轻与重。  相似文献   

大学生创业素质模型的构建及其评价   总被引：6，自引：0，他引：6  

王林雪  邓俊荣  彭璐 《中国青年科技》2007,(9):22-27

胜任素质研究是人力资源管理的新概念,它建立在胜任素质理论基础之上。提高大学生群体的创业素质,是培养高素质创业家、企业家的有效途径。本文在素质模型理论和创业理论指导下对大学生创业素质进行了探讨。通过对素质模型理论发展演进的理论综述,进而对大学生创业素质进行界定。通过问卷调查和数据统计分析,建立了大学生创业素质模型,重点运用层次分析法(AHP),对大学生创业素质模型指标体系赋予权重,并在此基础上通过专家咨询,运用模糊综合评价法对大学生样本的创业素质进行评价。在模糊综合评价的基础上,对大学生创业素质进行现状分析,并针对其不足之处提出了培养和提高策略,以求为高等院校创业教育提供有益参考。  相似文献   

基于软件质量管理中的软件过程改进   总被引：1，自引：0，他引：1  

车光毅  刘南根 《科技广场》2004,(7):12-15

本文介绍软件过程的概念及其框架，通过分析软件过程改进的动机，给出其改进的环境框架和基本步骤。并讲述了一种提高软件过程能力途径的CMM。  相似文献   

用层次分析法评测联想、海尔、戴尔(中国)三家企业网站   总被引：4，自引：1，他引：4  

韩洁平  王欣 《情报科学》2003,21(12):1289-1292,1301

本文依据美国评价电子商务网站的权威标准，对联想、海尔、戴尔三家企业的商务网站进行了调查分析，形成综合调查报告。然后通过层次分析法对三家企业网站做了对比分析，得到了具有理论指导意义和现实应用价值的结论。  相似文献