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Journal of Environmental Sciences 2024年第2期136卷 547-558页

作者： Yong Wang Cheng Liu Haoyun Hu qiujun lu Haiyan Wang Chenxi Zhao Fuyou Du Ningli Tang Guangxi Key Laboratory of Electrochemical and Magnetochemical Functional Materials College of Chemistry and BioengineeringGuilin University of TechnologyGuilin 541004China College of Biological and Environmental Engineering Changsha UniversityChangsha 410022China

The construction and application of novel highly efficient photocatalysts have been the focus in the field of environmental pollutant removal.In this work,a novel CuFe_(2)O_(4)/Bi_(12)O_(17)Cl_(2)photocatalysts were synthesized by simple hydrothermal and chemical precipitation method.The fabricated CuFe_(2)O_(4)/Bi_(12)O_(17)Cl_(2)composite exhibited much higher photocatalytic activity than pristine CuFe_(2)O_(4)and Bi_(12)O_(17)Cl_(2)in the removal of bisphenol A(BPA)under visible-light illumination,which ascribed to the intrinsic p-n junction of CuFe_(2)O_(4)and Bi_(12)O_(17)Cl_(2).The photocatalytic degradation rate of BPA on CuFe_(2)O_(4)/Bi_(12)O_(17)Cl_(2)with an optimized CuFe_(2)O_(4)content(1.0 wt.%)reached 93.0%within 30 min.The capture experiments of active species confirmed that the hydroxyl radicals(·OH)and superoxide radicals(·O_(2)^(-))played crucial roles in photocatalytic BPA degradation process.Furthermore,the possible degradation mechanism and pathways of BPA was proposed according to the detected intermediates in photocatalytic reaction process.

关键词： Bi_(12)O_(17)Cl_(2) CuFe_(2)O_(4) Heterojunction Bisphenol A Photocatalytic degradation

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Probabilistic Fuzzy Regression Approach from the Point of View Risk

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Journal of Data Analysis and Information Processing 2018年第4期6卷 156-167页

作者： Nana Gao qiujun lu College of Science University of Shanghai for Science and Technology Shanghai China

Fuzzy regression analysis is an important regression analysis method to predict uncertain information in the real world. In this paper, the input data are crisp with randomness;the output data are trapezoid fuzzy number, and three different risk preferences and chaos optimization algorithm are introduced to establish fuzzy regression model. On the basis of the principle of the minimum total spread between the observed and the estimated values, risk-neutral, risk-averse, and risk-seeking fuzzy regression model are developed to obtain the parameters of fuzzy linear regression model. Chaos optimization algorithm is used to determine the digital characteristic of random variables. The mean absolute percentage error and variance of errors are adopted to compare the modeling results. A stock rating case is used to evaluate the fuzzy regression models. The comparisons with five existing methods show that our proposed method has satisfactory performance.

关键词： Probabilistic Fuzzy Regression Chaos Optimization Algorithm Risk Preferences Models Mean Absolute Percentage Error Variance of Errors

Robust Regression Analysis with LR-Type Fuzzy Input Variables and Fuzzy Output Variable

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Journal of Data Analysis and Information Processing 2016年第2期4卷 64-80页

作者： Dan Zhang qiujun lu College of Science University of Shanghai for Science and Technology Shanghai China

In this paper, we propose a fuzzy linear regression model with LR-type fuzzy input variables and fuzzy output variable, the fuzzy extent of which may be different. Then we give the iterative solution of the proposed model based on the Weighted Least Squares estimation procedure. Some properties of the estimates are proved. We also define suitable goodness of fit index and its adjusted version useful to evaluate the performances of the proposed model. Based on the Least Median Squares-Weighted Least Squares (LMS-WLS) estimation procedure, we give robust estimation steps for the proposed model. Compared with the well-known fuzzy Least Squares method, the effectiveness of our model on reducing the outliers influence is shown by using two examples.

关键词： LR-Type Fuzzy Input Variables LR-Type Fuzzy Output Variable LMS-WLS Outliers Robust

Fuzzy Varying Coefficient Bilinear Regression of Yield Series

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Journal of Data Analysis and Information Processing 2015年第3期3卷 43-54页

作者： Ting He qiujun lu College of Science University of Shanghai for Science and Technology Shanghai China

We construct a fuzzy varying coefficient bilinear regression model to deal with the interval financial data and then adopt the least-squares method based on symmetric fuzzy number space. Firstly, we propose a varying coefficient model on the basis of the fuzzy bilinear regression model. Secondly, we develop the least-squares method according to the complete distance between fuzzy numbers to estimate the coefficients and test the adaptability of the proposed model by means of generalized likelihood ratio test with SSE composite index. Finally, mean square errors and mean absolutely errors are employed to evaluate and compare the fitting of fuzzy auto regression, fuzzy bilinear regression and fuzzy varying coefficient bilinear regression models, and also the forecasting of three models. Empirical analysis turns out that the proposed model has good fitting and forecasting accuracy with regard to other regression models for the capital market.

关键词： Fuzzy Varying Coefficient Bilinear Regression Model Fuzzy Financial Assets Yield Least-Squares Method Generalized Likelihood Ratio Test Forecast

Estimate Beta Coefficient of CAPM Based on a Fuzzy Regression with Interactive Coefficients

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Journal of Applied Mathematics and Physics 2015年第6期3卷 664-672页

作者： Yalei Du qiujun lu College of Science University of Shanghai for Science and Technology Shanghai China

In the Capital Asset Pricing Model (CAPM), beta coefficient is a very important parameter to be estimated. The most commonly used estimating methods are the Ordinary Least Squares (OLS) and some Robust Regression Techniques (RRT). However, these traditional methods make strong as sumptions which are unrealistic. In addition, The OLS method is very sensitive to extreme observations, while the RRT methods try to decrease the weights of the extreme observations which may contain substantial information. In this paper, a novel fuzzy regression method is proposed, which makes less assumptions and takes good care of the extreme observations. Simulation study and real word applications show that the fuzzy regression is a competitive method.

关键词： CAPM Beta Coefficient Fuzzy Regression Outlier

Regression Analysis of a Kind of Trapezoidal Fuzzy Numbers Based on a Shape Preserving Operator

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Journal of Data Analysis and Information Processing 2017年第3期5卷 96-114页

作者： Jie Sun qiujun lu University of Shanghai for Science and Technology Shanghai China

Fuzzy regression provides more approaches for us to deal with imprecise or vague problems. Traditional fuzzy regression is established on triangular fuzzy numbers, which can be represented by trapezoidal numbers. The independent variables, coefficients of independent variables and dependent variable in the regression model are fuzzy numbers in different times and TW, the shape preserving operator, is the only T-norm which induces a shape preserving multiplication of LL-type of fuzzy numbers. So, in this paper, we propose a new fuzzy regression model based on LL-type of trapezoidal fuzzy numbers and TW. Firstly, we introduce the basic fuzzy set theories, the basic arithmetic propositions of the shape preserving operator and a new distance measure between trapezoidal numbers. Secondly, we investigate the specific model algorithms for FIFCFO model (fuzzy input-fuzzy coefficient-fuzzy output model) and introduce three advantages of fit criteria, Error Index, Similarity Measure and Distance Criterion. Thirdly, we use a design set and two reference sets to make a comparison between our proposed model and the reference models and determine their goodness with the above three criteria. Finally, we draw the conclusion that our proposed model is reasonable and has better prediction accuracy, but short of robust, comparing to the reference models by the three goodness of fit criteria. So, we can expand our traditional fuzzy regression model to our proposed new model.

关键词： Fuzzy Sets LL-Type of Trapezoidal Fuzzy Numbers Least-Squares Deviations Shape Preserving Operator Fuzzy Linear Regression

Fuzzy Regression Model Based on Fuzzy Distance Measure

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Journal of Data Analysis and Information Processing 2018年第3期6卷 126-140页

作者： Jun Deng qiujun lu University of Shanghai for Science and Technology Shanghai China

Some existed fuzzy regression methods have some special requirements for the object of study, such as assuming the observed values as symmetric triangular fuzzy numbers or imposing a non-negative constraint of regression parameters. In this paper, we propose a left-right fuzzy regression method, which is applicable to various forms of observed values. We present a fuzzy distance and partial order between two left-right (LR) fuzzy numbers and we let the mean fuzzy distance between the observed and estimated values as the mean fuzzy error, then make the mean fuzzy error minimum to get the regression parameter. We adopt two criteria involving mean fuzzy error (comparative mean fuzzy error based on partial order) and SSE to compare the performance of our proposed method with other methods. Finally four different types of numerical examples are given to illustrate that our proposed method has feasibility and wide applicability.

关键词： LR Fuzzy Number LR Fuzzy Distance Measure Mean Fuzzy Error Fuzzy Regression

稀土金属有机配合物的合成、结构和力致发光性质

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大学化学 2024年第5期39卷 363-370页

作者：陈天云肖瑞麟顾欣晟邵云一卢求钧长沙学院生物与化学工程学院

力致发光材料因其具有外力作用诱导产生发光的独特性质，其在冲击力、应力、张力或压力等作用力的传感，以及显示、照明、成像等领域具有巨大应用潜力，近年来引起了人们广泛关注。实验以二苯甲酰甲烷（DBM）、Eu（NO3）3和三乙胺（TEA... 详细信息

力致发光材料因其具有外力作用诱导产生发光的独特性质，其在冲击力、应力、张力或压力等作用力的传感，以及显示、照明、成像等领域具有巨大应用潜力，近年来引起了人们广泛关注。实验以二苯甲酰甲烷（DBM）、Eu（NO3）3和三乙胺（TEA）为原料，通过共沉淀法快速合成了离子型Eu3+配合物Eu（DBM）4TEA。采用紫外-可见吸收光谱、红外吸收光谱和X射线衍射谱对配合物的结构进行表征，并测定配合物的荧光性质和力致发光性能。本实验是在现有科研成果的基础上开发的包含稀土金属有机配合物合成、产物仪器表征和产物性能模块化综合化学实验，实现了科教融合；实验原料廉价、实验操作简单，模块化的设计机动灵活，能满足基础实验、综合实验和趣味科普实验等不同层次本科教学需求；实验现象可视，有助于激发学生学习兴趣，提升学生专业认同感。

关键词：力致发光铕离子配合物综合化学实验

来源：博看期刊

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不同商品有机肥对铁皮石斛产量和品质的影响

浙江农业科学 2024年第1期65卷 73-76页

作者：叶雄方陆秋君周翔陈尚取夏华芳向焘王玉萍毛碧增浙江传化生物技术有限公司浙江杭州311231 杭州市农业农村事务保障中心浙江杭州310000 淳安县农业农村发展服务中心浙江杭州311700 浙江大学生物技术研究所浙江杭州310058

为研究不同商品有机肥对铁皮石斛产量和品质的影响,本研究以三年生铁皮石斛为材料,探讨金福伊农生物有机肥、百泰微生物肥料、大汉rutom MIX 1这3种商品有机肥对铁皮石斛生长、开花特性和多糖含量的影响,以期筛选出合适铁皮石斛有机栽... 详细信息

为研究不同商品有机肥对铁皮石斛产量和品质的影响,本研究以三年生铁皮石斛为材料,探讨金福伊农生物有机肥、百泰微生物肥料、大汉rutom MIX 1这3种商品有机肥对铁皮石斛生长、开花特性和多糖含量的影响,以期筛选出合适铁皮石斛有机栽培的底肥,为铁皮石斛有机栽培肥料施用提供依据。结果表明,667 m^(2)施用金福伊农生物有机肥160 kg,能够显著促进铁皮石斛新芽萌发、茎秆伸长、多糖含量增加;百泰微生物肥料有利于铁皮石斛叶片生长;相较于前两者,大汉rutom MIX 1在促进铁皮石斛生长上效果不明显。

关键词：铁皮石斛商品有机肥有机栽培产量品质

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我国科技投入对保险需求的影响分析

科技进步与对策 2007年第12期24卷 26-29页

作者：陆秋君上海理工大学理学院上海200093

在影响保险需求的诸多因素中,知识资本已经成为一个越来越备受关注的因素,而科技投入无疑是知识资本形成的首要条件。以1980～2004年度统计数据为基础,实证分析了科技投入对保险需求的影响。结果表明:①科技投入与保险需求之间不存在Gra... 详细信息

在影响保险需求的诸多因素中,知识资本已经成为一个越来越备受关注的因素,而科技投入无疑是知识资本形成的首要条件。以1980～2004年度统计数据为基础,实证分析了科技投入对保险需求的影响。结果表明:①科技投入与保险需求之间不存在Granger双向因果关系;②科技投入与收入、教育投入同保险需求之间存在协整关系,表明科技投入构成了保险需求的长期因;③科技投入对保险需求的贡献率为-0.158,也就是说,技术进步对保险需求的提升作用小于对其的抑制作用。为此,应挖掘科技投入对保险需求增长的促进作用,不仅要关注增加科技投入的总量,更要重视优化科技投入的结构和提高科技资源的使用效率。

关键词：保险需求保险密度科技投入 Granger果关系检验

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