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Robust Variable Selection and Estimation in Threshold Regression Model

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Acta Mathematicae Applicatae Sinica 2020年第2期36卷 332-346页

作者： Bo-wen LI Yun-qi ZHANG nian-sheng tang School of Management University of Science and Technology of ChinaHefei 230026China Key Lab of Statistical Modeling and Data Analysis of Yunnan Province Yunnan UniversityKunming 650091China

We combine the robust criterion with the lasso penalty together for the high-dimensional threshold *** estimates regression coefficients as well as the threshold parameter robustly that can be resistant to outliers or heavy-tailed noises and perform variable selection *** illustrate our approach with the absolute loss,the Huber’s loss,and the Tukey’s loss,it can also be extended to any other robust *** studies are conducted to demonstrate the usefulness of our robust ***,we use our estimators to investigate the presence of a shift in the effect of debt on future GDP growth.

关键词： Threshold regression Robust estimation Lasso

Local Influence Analysis for Semiparametric Reproductive Dispersion Nonlinear Models

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Acta Mathematicae Applicatae Sinica 2012年第1期28卷 75-90页

作者： Xue-dong CHEN nian-sheng tang Xue-ren WANG Department of Statistics Yunnan UniversityKunming 650091China

The present paper proposes a semiparametric reproductive dispersion nonlinear model （SRDNM） which is an extension of the nonlinear reproductive dispersion models and the semiparameter regression models. Maximum penalized likelihood estimates （MPLEs） of unknown parameters and nonparametric functions in SRDNM are presented. Assessment of local influence for various perturbation schemes are investigated. Some local influence diagnostics are given. A simulation study and a real example are used to illustrate the proposed methodologies.

关键词： local influence analysis maximum penalized likelihood estimate nonlinear reproductive dispersionmodels semiparametric regression model

Equilibrium and mechanism studies of gold(Ⅰ)extraction from alkaline aurocyanide solution by using fluorine-free ionic liquids

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Rare Metals 2021年第7期40卷 1987-1994页

作者： Ya-Ting Wang Men Liu nian tang Sheng-Jian Li Yan Sun Shi-Xiong Wang Xiang-Jun Yang Key Laboratory of Medicinal Chemistry for Natural Resource(Yunnan University) Ministry EducationSchool of Chemical Science and TechnologyYunnan UniversityKunming 650091China

Solvent extraction based on ionic liquids is generally considered to be an environmentally benign and effective technology for gold(Ⅰ)*** aim of this work is to study gold(Ⅰ)extraction from aurocyanide solution using fluorine-free ionic liquids[A336][SCN],[A336][MTBA]and[A336][Mal].Various factors that affect gold(Ⅰ)extraction(including concentration of ionic liquids,equilibrium pH,concentration of the modifier tributyl phosphate(TBP),reaction time and initial concentration of gold in an aqueous solution)were studied and *** results indicate that the three Aliquat336-based ionic liquids all exhibit excellent behaviors for gold(Ⅰ)*** than 99.8%of gold(Ⅰ)can be extracted from the aqueous phase into the ionic liquid *** gold-loaded ionic liquids were characterized using infrared spectroscopy and mass spectrometry to study the extraction mechanism of gold(Ⅰ).The results revealed that extraction of gold(Ⅰ)into the ionic liquid phase was based on an exchange reaction between the anion Au(CN)2-in aqueous solution and the anion SCN-in ionic liquid[A336][SCN].The logarithmic relationship between distribution coefficient and TBP concentration indicates that two TBP molecules are involved in the formation of the extracted *** extracted complex was determined to be A336^(+)·Au(CN)_(2)^(-)·2 *** addition,the gold(Ⅰ)-loaded ionic liquids can be efficiently stripped using NH4 SCN,2-methylthiobenzoic acid and methyl *** results establish that Aliquat 336-based ionic liquids have potential application prospects in gold(Ⅰ)recovery from cyanide solutions.

关键词： Gold(Ⅰ) Solvent extraction Ionic liquid Alkaline aurocyanide solution

Early warning research on salt-alkalization desertification in western Songnen Plain

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Journal of Geoscientific Research in Northeast Asia 2005年第1期8卷 116-122页

作者： BIAN Jian-min LIN nian-feng tang Jie College of Environment and Resources Jilin University Changchun 130026 Jilin China

Desertification is an environmental issue in the world. The salt-alkalization desertification land area formed by both primary and secondary salt-alkalization has extended in a large scale, which has become a significant eco-environmental problem. Based on the characteristics of eco-environment and the situation of desertification in westem Songnen plain, this paper reports the analyzes of its formation in background and cause. An early waming system on the salt-alkalization desertification is established and the GIS technology is used to abstract the information of desertification evaluation index. Supported by the integrated technology of the GIS and ANN, the orientation and quantitative result of desertification are gained, which is helpful to the eco-environment protection and resource development in westem Songnen Plain.

关键词： western Songnen plain early warning system GIS-EIS integrated technology salt-alkalization desertification

Effect of simvastatin on endothelium-dependent vaso-relaxation and endogenous nitric oxide synthase inhibitor

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Acta Pharmacologica Sinica 2004年第7期25卷 47-55页

作者： Jun-lin JIANG, De-jian JIANG, Yu-hai tang, nian-sheng LI, Han-wu DENG, Yuan-jian LI1 Department of Pharmacology, Schoolof Pharmaceutic Sciences, Central South University, Changsha 410078, China Department of Pharmacology School of Pharmaceutic Sciences Central South University Changsha 410078

AIM: To investigate the effect of simvastatin on endothelium-dependent vasorelaxation and endogenous nitric oxide synthesis inhibitor asymmetric dimethylarginine (ADMA) in rats and cultured ECV304 cells. METHODS: Endothe- lial injury was induced by a single injection of low density lipoprotein (LDL) (4 mg/kg, 48 h) in rats or incubation with LDL (300 mg/L) or oxidative-modified LDL (100 mg/L) in cultured ECV304 cells, and vasodilator responses to acetylcholine (ACh) in the aortic rings and the level of ADMA, nitrite/nitrate (NO) and tumor necrosis factor- alpha (TNF-α) in the serum or cultured medium were determined. And the adhesion of the monocytes to endothe- lial cells and the activity of dimethylarginine dimethylaminohydrolase (DDAH) in the cultured ECV304 cells were measured. RESULTS: A single injection of LDL decreased endothelium-dependent relaxation to ACh, markedly increased the serum level of endogenous ADMA and TNF-α, and reduced serum level of NO. Pretreatment with simvastatin (30 or 60 mg/kg) markedly attenuated inhibition of vasodilator responses to ACh, the increased level of TNF-α and the decreased level of NO by LDL, but no effect on serum concentration of endogenous ADMA. In cultured ECV304 cells, LDL or ox-LDL markedly increased the level of ADMA and TNF-α and potentiated the adhesion of monocytes to endothelial cells, concomitantly with a significantly decrease in the activity of DDAH and serum level of NO. Pretreatment with simvastatin (0.1, 0.5, or 2.5 μmol/L) markedly decreased the level of TNF- α and the adhesion of monocytes to endothelial cells, butdid not affectthe concentration of endogenous ADMA and the activity of DDAH. CONCLUSION: Simvastatin protect the vascular endothelium against the damages induced by LDL or ox-LDL in rats or cultured ECV304 cells, and the beneficial effects of simvastatin may be related to the reduction of inflammatory cytokine TNF-α level.

关键词： simvastatin vasodilation tumor necrosis factor endogenous nitric oxide synthase inhibitor LDL lipoproteins

基于Multi-Agent的电子商务中的恶意Agent研究

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计算机科学 2008年第9期35卷 289-291页

作者：唐年庆内江师范学院计算机与信息科学系内江641112

描述并讨论了以Agent为中介的电子商务中的恶意Agent问题。恶意Agent是一种带有不良意图,能够攻击标准代理,扰乱交易,欺骗用户,盗窃机密信息,浪费资源和破坏市场等的软件实体,在某些方面它们比PC病毒更有危害。为此提出了SCAAM,并且用... 详细信息

描述并讨论了以Agent为中介的电子商务中的恶意Agent问题。恶意Agent是一种带有不良意图,能够攻击标准代理,扰乱交易,欺骗用户,盗窃机密信息,浪费资源和破坏市场等的软件实体,在某些方面它们比PC病毒更有危害。为此提出了SCAAM,并且用一些策略来具体描述这种模型的工作过程。

关键词： Agent 恶意代理电子商务 SCAAM

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基于遗传控制的传感器节点轮换调度算法

控制工程 2016年第2期23卷 254-258页

作者：唐年庆内江师范学院计算机科学学院四川内江641112

为优化无线传感器网络(Wireless Sensor Network,WSN)中各节点的部署与定位,常常需要采取一定的自适应轮换调度算法。传统的调度算法大都采用基于信息度增益控制的节点定位技术进行设计,算法性能随着迭代次数的增加而下降。为此提出了... 详细信息

为优化无线传感器网络(Wireless Sensor Network,WSN)中各节点的部署与定位,常常需要采取一定的自适应轮换调度算法。传统的调度算法大都采用基于信息度增益控制的节点定位技术进行设计,算法性能随着迭代次数的增加而下降。为此提出了一种基于遗传控制的传感器节点自适应轮换调度算法,该算法利用遗传适应度函数对群体中的每个特征量进行自适应计算,结合变异遗传散布控制量与LSSVM训练模型对传感器节点进行优化部署,实现了对传感器节点的自适应轮换调度。经过实验仿真,结果表明,采用该算法实现对传感器网络节点的自适应轮换调度,能有效提高传感器网络定位的准确性,并提高传感器网络的生命周期,节省能量开销,提高网络的生存能力。

关键词：传感器遗传控制自适应轮换调度

三元缔合物以双波长共振瑞利散射测定药物中酒石酸美托洛尔

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分析试验室 2018年第5期37卷 537-542页

作者：唐念江虹长江师范学院化学化工学院武陵山片区绿色发展协同创新中心重庆408100

建立了一种快速、准确测定药物中酒石酸美托洛尔的双波长共振瑞利散射(DWORRS)新方法。在酸性Tris-盐酸介质中,刚果红与酒石酸美托洛尔及表面活性剂十六烷基三甲基溴化铵反应生成红色三元缔合物,使双波长共振瑞利散射显著增强并产生新... 详细信息

建立了一种快速、准确测定药物中酒石酸美托洛尔的双波长共振瑞利散射(DWORRS)新方法。在酸性Tris-盐酸介质中,刚果红与酒石酸美托洛尔及表面活性剂十六烷基三甲基溴化铵反应生成红色三元缔合物,使双波长共振瑞利散射显著增强并产生新的具有2个明显散射峰的共振瑞利散射(RRS)光谱,最大共振瑞利散射峰位于375 nm,另一共振瑞利散射峰位于515 nm,酒石酸美托洛尔在0.004~0.55 mg/L范围内与体系的RRS增强强度的绝对值(│△I_(RRS)│)呈线性关系,检出限为0.0032 mg/L(375 nm),0.0038 mg/L(515 nm)和0.0018 mg/L(DWO-RRS,375 nm+515 nm)。还探讨了RRS的光谱特征、适宜反应条件、反应机理及共存物质的影响。方法用于药物中酒石酸美托洛尔含量的测定,加标回收率为98.57%~102.1%,相对标准偏差为2.0%~2.5%。

关键词：双波长共振瑞利散射刚果红十六烷基三甲基溴化铵酒石酸美托洛尔三元缔合物

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大型煤粉锅炉汞的排放特性和迁移规律研究

燃料化学学报 2013年第4期41卷 484-490页

作者：唐念盘思伟广东电网公司电力科学研究院广东广州510080

采用EPA 30B方法,对某大型火电厂四台典型煤粉锅炉进行了烟气Hg排放测试,并选取其中两台代表性锅炉对各输入/输出物料进行了Hg量对比分析。通过系统的汞质量平衡核算,得出各物料中汞所占的比例,并据此分析了选择性催化还原脱硝装置(SCR... 详细信息

采用EPA 30B方法,对某大型火电厂四台典型煤粉锅炉进行了烟气Hg排放测试,并选取其中两台代表性锅炉对各输入/输出物料进行了Hg量对比分析。通过系统的汞质量平衡核算,得出各物料中汞所占的比例,并据此分析了选择性催化还原脱硝装置(SCR)、静电除尘器(ESP)和湿法脱硫装置(WFGD)等主要烟气净化设施对汞排放的影响,在此基础上研究得到系统汞的迁移规律。结果表明,四台锅炉的烟气Hg排放浓度都不高,普遍在3μg/m3以下,明显低于新国标规定的排放限值,其中,配备SCR时Hg排放浓度明显更低。其原因在于,设置有SCR时,烟气中相当部分的Hg0会被催化氧化成Hg2+,Hg2+易于被飞灰吸附而脱除。WFGD对Hg2+的吸收比Hg0强得多,因此,排放烟气中汞的形态以Hg0为主,吸收的Hg绝大部分转移至脱硫石膏中。脱硫废水和炉渣对Hg的富集能力都非常有限。

关键词：汞排放迁移选择性催化还原湿法脱硫静电除尘器