识别和消除杂波是确保雷达信息数据质量的必要条件。对于信号处理后的未校正扫描反射率,通常通过水平插值,高污染的非污染PPI外推或基于降水类型的分类将两者结合来重建被去除的区域。提出了一种顾及多距射影空间测量方法的自适应雷达...识别和消除杂波是确保雷达信息数据质量的必要条件。对于信号处理后的未校正扫描反射率,通常通过水平插值,高污染的非污染PPI外推或基于降水类型的分类将两者结合来重建被去除的区域。提出了一种顾及多距射影空间测量方法的自适应雷达信息质量评估方法。该方法通过多维半变异函数提供的场空间和时间变化来适应数据类型,并与最初观察到的值在无杂波区域上进行比较,以及通过与来自雨量器的信息数据累积进行比较,并在真实的杂波污染区域上进行评估。实验结果表明:体积-时间重建(high value volum,HVN)通常优于体积重建(high volum,HV),而HVN获得的结果通常与HV的结果非常相似。展开更多
设计主动式地理信息服务质量(quality of active geospatial information service,QoAGIS)评估系统,阐述主动式地理信息服务的内涵及其逻辑结构,提出AGIS质量评估指标的概念,并对其中的本征质量指标与广义质量指标的定量化实现进行研究...设计主动式地理信息服务质量(quality of active geospatial information service,QoAGIS)评估系统,阐述主动式地理信息服务的内涵及其逻辑结构,提出AGIS质量评估指标的概念,并对其中的本征质量指标与广义质量指标的定量化实现进行研究,给出综合评估指标。最后,通过实验表明QoAGIS评估系统的适应性和可靠性。展开更多
Image enhancement is a popular technique,which is widely used to improve the visual quality of images.While image enhancement has been extensively investigated,the relevant quality assessment of enhanced images remain...Image enhancement is a popular technique,which is widely used to improve the visual quality of images.While image enhancement has been extensively investigated,the relevant quality assessment of enhanced images remains an open problem,which may hinder further development of enhancement techniques.In this paper,a no-reference quality metric for digitally enhanced images is proposed.Three kinds of features are extracted for characterizing the quality of enhanced images,including non-structural information,sharpness and naturalness.Specifically,a total of 42 perceptual features are extracted and used to train a support vector regression(SVR) model.Finally,the trained SVR model is used for predicting the quality of enhanced images.The performance of the proposed method is evaluated on several enhancement-related databases,including a new enhanced image database built by the authors.The experimental results demonstrate the efficiency and advantage of the proposed metric.展开更多
The voluntary disclosure studies conducted until today, in social accounting and related fields, use different approaches to evaluate the so-called ＂disclosure quality＂. Disclosure quality is not so easy to measure,...The voluntary disclosure studies conducted until today, in social accounting and related fields, use different approaches to evaluate the so-called ＂disclosure quality＂. Disclosure quality is not so easy to measure, and it is derived from the application of different methodologies. In particular, the methodologies to assess the level of disclosure could be classified as subjective or objective. To the first category belong all the ＂tools＂ that are used directly without relying on the analysis of the original source of the information studies （Imhoff, 1992; Coleman ＆ Eccles, 1997; Welker, 1995）. The objective measurements used to assess the disclosure quality are, instead, based on the direct study of the original information source in order to obtain the information required （Krippendorff, 1980; Weber, 1985; Botosan, 1997; Lang ＆ Lundholm, 2000）. The aim of the paper is to give scholars and researchers a brief framework to understand the different methodologies used in accounting literature to assess the disclosure quality, providing examples of the application of the same in different research contexts.展开更多
Based on the fuzzy characters of eco-environmental quality conception and classification standards, the incompatibility of evaluation indexes, the statistical fluctuation of index values, an information entropy fuzzy ...Based on the fuzzy characters of eco-environmental quality conception and classification standards, the incompatibility of evaluation indexes, the statistical fluctuation of index values, an information entropy fuzzy matter-element model for evaluating regional eco-environmental quality is proposed by way of comprehensively utilizing such theories as information theory, fuzzy sets and matter-element theory, etc. As a case, the model established here is used to evaluate the eco-environmental quality of Lake Chaohu basin. In the case, the eco-environmental quality standards and the evaluated schemes are indicated as matter-elements, together. Through constructing compound fuzzy matter-element, probability compound fuzzy matter-element and self-information compound fuzzy matter- element, the information entropy of each matter-element （including evaluated schemes and classification standards） is calculated in the end. According to these obtained information entropy values, the evaluated schemes can be not only arranged in quality state order but also classified by classification standards .Study result shows that information entropy fuzzy matter-element model is suitable for regional eco-environmental quality assessment.展开更多
文摘识别和消除杂波是确保雷达信息数据质量的必要条件。对于信号处理后的未校正扫描反射率,通常通过水平插值,高污染的非污染PPI外推或基于降水类型的分类将两者结合来重建被去除的区域。提出了一种顾及多距射影空间测量方法的自适应雷达信息质量评估方法。该方法通过多维半变异函数提供的场空间和时间变化来适应数据类型,并与最初观察到的值在无杂波区域上进行比较,以及通过与来自雨量器的信息数据累积进行比较,并在真实的杂波污染区域上进行评估。实验结果表明:体积-时间重建(high value volum,HVN)通常优于体积重建(high volum,HV),而HVN获得的结果通常与HV的结果非常相似。
文摘设计主动式地理信息服务质量(quality of active geospatial information service,QoAGIS)评估系统,阐述主动式地理信息服务的内涵及其逻辑结构,提出AGIS质量评估指标的概念,并对其中的本征质量指标与广义质量指标的定量化实现进行研究,给出综合评估指标。最后,通过实验表明QoAGIS评估系统的适应性和可靠性。
基金supported in part by the National Natural Science Foundation of China under Grant 61379143in part by the Fundamental Research Funds for the Central Universities under Grant 2015QNA66in part by the Qing Lan Project of Jiangsu Province
文摘Image enhancement is a popular technique,which is widely used to improve the visual quality of images.While image enhancement has been extensively investigated,the relevant quality assessment of enhanced images remains an open problem,which may hinder further development of enhancement techniques.In this paper,a no-reference quality metric for digitally enhanced images is proposed.Three kinds of features are extracted for characterizing the quality of enhanced images,including non-structural information,sharpness and naturalness.Specifically,a total of 42 perceptual features are extracted and used to train a support vector regression(SVR) model.Finally,the trained SVR model is used for predicting the quality of enhanced images.The performance of the proposed method is evaluated on several enhancement-related databases,including a new enhanced image database built by the authors.The experimental results demonstrate the efficiency and advantage of the proposed metric.
文摘The voluntary disclosure studies conducted until today, in social accounting and related fields, use different approaches to evaluate the so-called ＂disclosure quality＂. Disclosure quality is not so easy to measure, and it is derived from the application of different methodologies. In particular, the methodologies to assess the level of disclosure could be classified as subjective or objective. To the first category belong all the ＂tools＂ that are used directly without relying on the analysis of the original source of the information studies （Imhoff, 1992; Coleman ＆ Eccles, 1997; Welker, 1995）. The objective measurements used to assess the disclosure quality are, instead, based on the direct study of the original information source in order to obtain the information required （Krippendorff, 1980; Weber, 1985; Botosan, 1997; Lang ＆ Lundholm, 2000）. The aim of the paper is to give scholars and researchers a brief framework to understand the different methodologies used in accounting literature to assess the disclosure quality, providing examples of the application of the same in different research contexts.
文摘Based on the fuzzy characters of eco-environmental quality conception and classification standards, the incompatibility of evaluation indexes, the statistical fluctuation of index values, an information entropy fuzzy matter-element model for evaluating regional eco-environmental quality is proposed by way of comprehensively utilizing such theories as information theory, fuzzy sets and matter-element theory, etc. As a case, the model established here is used to evaluate the eco-environmental quality of Lake Chaohu basin. In the case, the eco-environmental quality standards and the evaluated schemes are indicated as matter-elements, together. Through constructing compound fuzzy matter-element, probability compound fuzzy matter-element and self-information compound fuzzy matter- element, the information entropy of each matter-element （including evaluated schemes and classification standards） is calculated in the end. According to these obtained information entropy values, the evaluated schemes can be not only arranged in quality state order but also classified by classification standards .Study result shows that information entropy fuzzy matter-element model is suitable for regional eco-environmental quality assessment.
