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Yarn Quality Prediction for Small Samples Based on AdaBoost Algorithm 被引量:1
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作者 刘智玉 陈南梁 汪军 《Journal of Donghua University(English Edition)》 CAS 2023年第3期261-266,共6页
In order to solve the problems of weak prediction stability and generalization ability of a neural network algorithm model in the yarn quality prediction research for small samples,a prediction model based on an AdaBo... In order to solve the problems of weak prediction stability and generalization ability of a neural network algorithm model in the yarn quality prediction research for small samples,a prediction model based on an AdaBoost algorithm(AdaBoost model) was established.A prediction model based on a linear regression algorithm(LR model) and a prediction model based on a multi-layer perceptron neural network algorithm(MLP model) were established for comparison.The prediction experiments of the yarn evenness and the yarn strength were implemented.Determination coefficients and prediction errors were used to evaluate the prediction accuracy of these models,and the K-fold cross validation was used to evaluate the generalization ability of these models.In the prediction experiments,the determination coefficient of the yarn evenness prediction result of the AdaBoost model is 76% and 87% higher than that of the LR model and the MLP model,respectively.The determination coefficient of the yarn strength prediction result of the AdaBoost model is slightly higher than that of the other two models.Considering that the yarn evenness dataset has a weaker linear relationship with the cotton dataset than that of the yarn strength dataset in this paper,the AdaBoost model has the best adaptability for the nonlinear dataset among the three models.In addition,the AdaBoost model shows generally better results in the cross-validation experiments and the series of prediction experiments at eight different training set sample sizes.It is proved that the AdaBoost model not only has good prediction accuracy but also has good prediction stability and generalization ability for small samples. 展开更多
关键词 stability and generalization ability for small samples.key words:yarn quality prediction AdaBoost algorithm small sample generalization ability
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项目措辞方向与NEP量表在中国应用的再评估 被引量:3
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作者 范叶超 《南京工业大学学报(社会科学版)》 CSSCI 2017年第2期62-69,共8页
项目措辞方向会对NEP量表在中国应用时的测量质量产生影响吗?利用问卷调查数据,本研究评估了NEP量表在中国大学生群体中的应用情况,并特别关注项目措辞方向差异对量表测量质量的影响。研究发现:(1)项目措辞方向的不一致确实干扰了NEP量... 项目措辞方向会对NEP量表在中国应用时的测量质量产生影响吗?利用问卷调查数据,本研究评估了NEP量表在中国大学生群体中的应用情况,并特别关注项目措辞方向差异对量表测量质量的影响。研究发现:(1)项目措辞方向的不一致确实干扰了NEP量表的内部一致性和维度结构,统一方向后,量表的内部一致性明显提升,理论维度也更加明确;(2)统一措辞方向后NEP量表的预测效度并不理想,但在拆解为5个子量表后,预测效度得到了明显改善;(3)统一措辞方向后的NEP量表是大学生环境关心的最佳测量工具。进一步,研究对项目措辞方向为何会影响量表测量质量做出了解释,并明确了未来使用NEP量表应当注意的事项。 展开更多
关键词 环境关心 NEP量表 措辞方向 测量质量 大学生环境关心
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改革、创新环境质量纳入政府绩效考核办法
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作者 沈燕 蒋志刚 司蔚 《价值工程》 2012年第31期16-17,共2页
本文针对目前环境质量纳入政府绩效考核机制中存在问题,提出了改革、创新的考核办法。
关键词 环境质量 政府 考核 办法
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1978年—2014年中国环境财政研究现状及评价
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作者 金海音 张明星 田时中 《石家庄经济学院学报》 2016年第2期54-59,共6页
论文运用词频统计法和文献计量法,对CNKI收录的120篇核心期刊论文进行深入分析,评价中国环境财政研究现状。结果表明,中国环境财政研究呈现出几个特点:中国环境财政研究持续增加、研究主体集中于高等院校、研究主题突出、研究整体处在... 论文运用词频统计法和文献计量法,对CNKI收录的120篇核心期刊论文进行深入分析,评价中国环境财政研究现状。结果表明,中国环境财政研究呈现出几个特点:中国环境财政研究持续增加、研究主体集中于高等院校、研究主题突出、研究整体处在初级阶段及研究资助力度不足。建议研究者、研究机构、学术期刊和政府共同协作,促进中国环境财政研究质量有效提升,发挥环境财政对环境保护和环境治理的促进作用。 展开更多
关键词 环境财政 词频统计 文献计量 研究质量 协作
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校准曲线制备及应用中的一些问题
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作者 徐力生 《环境监测管理与技术》 1996年第6期43-44,共2页
阐述了校准曲线的制备和应用,标准加入法,空白值参与回归。
关键词 校准曲线 制备 应用 环境监测 分光光度法
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Water quality evaluation based on improved fuzzy matter-element method 被引量:22
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作者 Dongjun Liu Zhihong Zou 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第7期1210-1216,共7页
For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. Th... For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. The coefficient of variation of each indicator is used to determine the weight instead of traditional calculating superscales method. On the other hand, fuzzy matter-elements are constructed, and normal membership degrees are used instead of traditional trapezoidal ones. The composite fuzzy matter-elements with associated coefficient are constructed through associated transformation. The levels of natural water quality are determined according to the principle of maximum correlation. The improved fuzzy matter-element evaluation method is applied to evaluate water quality of the Luokou mainstream estuary at the first ten weeks in 2011 with the coefficient of variatiola method determining the weights. Water quality of Luokou mainstream estuary is dropping from level I to level II. The results of the improved evaluation method are basically the same as the official water quality. The variation coefficient method can reduce the workload, and overcome the adverse effects from abnormal values, compared with the traditional calculating superscales method. The results of improved fuzzy matter- element evaluation method are more credible than the ones of the traditional evaluation method. The improved evaluation method can use information of monitoring data more scientifically and comprehensively, and broaden a new evaluation method for water quality assessment. 展开更多
关键词 water quality improved fuzzy matter-element evaluation method synthetic evaluation variation coefficient method normal membership key words: water quality improved fuzzy matter-element evaluation method synthetic evaluation variation coefficient method normal membership
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Role of Institutional Quality in Determining the R&D Investment of Chinese Firms 被引量:3
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作者 Yixiao Zhou 《China & World Economy》 SCIE 2014年第4期60-82,共23页
This study adds to the understanding of China "s innovation prospects by examining how variations in institutional quality within China impact on the R &D efforts of firms located in different provincial regions. In... This study adds to the understanding of China "s innovation prospects by examining how variations in institutional quality within China impact on the R &D efforts of firms located in different provincial regions. In the process of identifying the effect of institutional quality, the roles of other factors such as ownership types and market structures are revealed, which provides interesting insight into firms " R&D behavior. The key findings suggest that institutional quality positively affects the decision offirms to engage in R&D activities. Once firms start to engage in R &D, the subsequent expansion of firm-level R &D intensity depends on factors such as market structure. Therefore, strengthening domestic institutional quality is the first critical step towards the goal of building a knowledge-intensive economy in China. Efforts to nurture market development are also important for achieving this goal. 展开更多
关键词 key words: innovation institutional quality R&D investment the Chinese economy
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识别河流水质模型参数的单纯形-差分进化混合算法 被引量:6
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作者 付翠 刘元会 +1 位作者 郭建青 袁华 《水力发电学报》 EI CSCD 北大核心 2015年第1期125-130,共6页
应用文中构造的单纯形-差分进化混合算法,分析了一维河流纵向离散和二维河流横向扩散两种情况下的水团示踪试验数据,识别了河流水质参数。这种混合算法是将具有局部搜索能力强、收敛速度快,而对初始值的选取依赖性较强等特点的单纯形算... 应用文中构造的单纯形-差分进化混合算法,分析了一维河流纵向离散和二维河流横向扩散两种情况下的水团示踪试验数据,识别了河流水质参数。这种混合算法是将具有局部搜索能力强、收敛速度快,而对初始值的选取依赖性较强等特点的单纯形算法与具有全局搜索能力强、受控参数少、而局部搜索能力弱等特点的差分算法进行混合。使其同时具有随机性搜索与确定性运算所具有的共同优点,能够较好地平衡局部搜索能力和全局搜索能力。数值实验结果表明:该算法可有效地应用于河流纵向离散和横向扩散两种情况下的水团示踪试验数据分析与水质参数识别,并且运算速度快、收敛性好,具有重要的应用价值。 展开更多
关键词 环境水力学 河流水质模型 单纯形-差分进化算法 纵向离散系数 横向扩散系数
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Limited Spatial Transferability of the Relationships Between Kriging Variance and Soil Sampling Spacing in Some Grasslands of Ireland:Implications for Sampling Design 被引量:3
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作者 SUN Xiaolin WANG Huili +3 位作者 Dermot FORRISTAL FU Weijun Hubert TUNNEY Chaosheng ZHANG 《Pedosphere》 SCIE CAS CSCD 2019年第5期577-589,共13页
Sampling plays an important role in acquiring precise soil information required in modern agricultural production worldwide, which determines both the cost and quality of final soil mapping products. For sampling desi... Sampling plays an important role in acquiring precise soil information required in modern agricultural production worldwide, which determines both the cost and quality of final soil mapping products. For sampling design, it has been proposed possibile to transfer the relationships between kriging variance and sampling grid spacing from an area with existing information to other areas with similar soil-forming environments. However, this approach is challenged in practice because of two problems: i) different population vaxiograms among similar areas and ii) sampling errors in estimated variograms. This study evaluated the effects of these two problems on the transferability of the relationships between kriging variance and sampling grid spacing, by using spatial data simulated with three variograms and soil samples collected from four grasslands in Ireland with similar soil-forming environments. Results showed that the variograms suggested by different samples collected with the same grid spacing in the same or similar areas were different, leading to a range of mean kriging variance (MKV) for each grid spacing. With increasing grid spacing, the variation of MKV for a specific grid spacing increased and deviated more from the MKV generated using the population variograms. As a result, the spatial transferability of the relationships between kriging variance and grid spacing for sampling design was limited. 展开更多
关键词 key words. geostatistics population variogram sampling error sampling grid spacing soil-forming environment soil information soil mapping spatial variability
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