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Sparse Support Vector Machine with Lp Penalty for Feature Selection

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Journal of Computer Science & Technology 2017年第1期32卷 68-77页

作者： lan Yao Feng Zeng Dong-Hui Li Zhi-Gang Chen College of Mathematics and Econometrics Hunan University Changsha 410082 China School of Software Central South University Changsha 410083 China School of Mathematical Sciences South China Normal University Guangzhou 510631 China

We study the strategies in feature selection with sparse support vector machine （SVM）. Recently, the socalled Lp-SVM （0 〈 p 〈 1） has attracted much attention because it can encourage better sparsity than the widely used L1-SVM. However, Lp-SVM is a non-convex and non-Lipschitz optimization problem. Solving this problem numerically is challenging. In this paper, we reformulate the Lp-SVM into an optimization model with linear objective function and smooth constraints （LOSC-SVM） so that it can be solved by numerical methods for smooth constrained optimization. Our numerical experiments on artificial datasets show that LOSC-SVM （0 〈 p 〈 1） can improve the classification performance in both feature selection and classification by choosing a suitable parameter p. We also apply it to some real-life datasets and experimental results show that it is superior to L1-SVM.

关键词： machine learning feature selection support vector machine Lp-regularization

On the characteristics of ADRC: a PID interpretation

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Science China(Information Sciences) 2020年第10期63卷 258-260页

作者： Huiyu JIN Jingchao SONG Weiyao lan Zhiqiang GAO School of Aerospace Engineering Xiamen University Center for Advanced Control Technologies Cleveland State University

Dear editor,This study reports the discovery of active disturbance rejection control (ADRC).Second-order linear ADRC (LADRC),the basic and most popular ADRC,can be interpreted as a modified proportional-integral-derivative (PID) *** filters the PID feedback compensator with a second-order low-pass filter;it also adds a ***,each given PID con-

关键词： Active disturbance rejection control PID Feedback compensator Bode plot Low-pass filter

高重复频率、高功率高次谐波极紫外光源进展及应用

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中国激光 2024年第7期51卷 3-21页

作者：魏子娟高熙泽孟翔宇李政言张庆斌兰鹏飞陆培祥华中科技大学光学与电子信息学院湖北武汉430074 华中科技大学物理学院湖北武汉430074 华中科技大学武汉光电国家研究中心湖北武汉430074 湖北光谷实验室湖北武汉430074

超短超强激光脉冲驱动的高次谐波是一种极紫外到软X射线波段的光源,具有指向性好、时空相干性高、亮度高等优点。高次谐波不但是在阿秒时间尺度上研究电子动力学的基础,而且其各类技术优点也使之成为一种有效的桌面型极紫外相干光源,在... 详细信息

超短超强激光脉冲驱动的高次谐波是一种极紫外到软X射线波段的光源,具有指向性好、时空相干性高、亮度高等优点。高次谐波不但是在阿秒时间尺度上研究电子动力学的基础,而且其各类技术优点也使之成为一种有效的桌面型极紫外相干光源,在集成电路制造在线检测、材料科学、生物医药等领域中具有广泛应用。然而,受限于传统钛蓝宝石固体飞秒激光的平均功率和高次谐波传播过程中的转换效率,目前高次谐波极紫外光源的平均功率亟待提高。介绍了高重复频率、高平均功率高次谐波极紫外光源的产生方式及其应用。首先介绍了光纤、固体、啁啾光学参量放大器等新型高重复频率、高平均功率飞秒激光驱动源在高次谐波产生方面的研究进展,之后讨论了激光高次谐波在弱电离气体介质中的宏观传播效应和相位匹配条件。在此基础上,介绍了高平均功率高次谐波极紫外光源在成像检测方面的应用。

关键词：非线性光学高次谐波极紫外光源飞秒激光器极紫外成像检测

Sources of nitrous and nitric oxides in paddy soils: Nitrification and denitrification

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Journal of Environmental Sciences 2014年第3期26卷 581-592页

作者： Ting lan Yong Han Marco Roelcke Rolf Nieder Zucong Cai State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Institute of Geoecology Technische Universitt Braunschweig School of Geography Sciences Nanjing Normal University

Rice-paddies are regarded as one of the main agricultural sources of N 2O and NO emissions. To date, however, specific N2O and NO production pathways are poorly understood in paddy soils. ^15N-tracing experiments were carded out to investigate the processes responsible for N2O and NO production in two paddy soils with substantially different soil properties. Laboratory incubation experiments were carried out under aerobic conditions at moisture contents corresponding to 60% of water holding capacity. The relative importance of nitrification and denitrification to the flux of NaO was quantified by periodically measuring and comparing the enrichments of the N2O, NH^-N and NO3-N pools. The results showed that both N2O and NO emission rates in an alkaline paddy soil with clayey texture were substantially higher than those in a neutral paddy soil with silty loamy texture. In accordance with most published results, the ammonium N pool was the main source of N2O emission across the soil profiles of the two paddy soils, being responsible for 59.7% to 97.7% of total N2O emissions. The NO3-N pool of N2O emission was relatively less important under the given aerobic conditions. The rates of N2O emission from nitrification （N2On） among different soil layers were significantly different, which could be attributed to both the differences in gross N nitrification rates and to the ratios of nitrified N emitted as NzO among soil layers. Furthermore, NO fluxes were positively correlated with the changes in gross nitrification rates and the ratios of NO/N2O in the two paddy soils were always greater than one （from 1.26 to 6.47）. We therefore deduce that, similar to N2O, nitrification was also the dominant source of NO in the tested paddy soils at water contents below 60% water holding capacity.

关键词： ^15N tracing model N2O NO NO/N2O nitrification denitrification

Influence of different post core materials on the color of Empress 2 full ceramic crowns

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Chinese Medical Journal 2006年第20期119卷 1715-1720页

作者： GE Jing WANG Xin-zhi FENG Hai-lan Department of Prosthodontics School and Hospital of StomatologyPeking University Beijing 100081 China

Background For esthetic consideration, dentin color post core materials were normally used for all-ceramic crown restorations. However, in some cases, clinicians have to consider combining a full ceramic crown with a metal post core. Therefore, this experiment was conducted to test the esthetical possibility of applying cast metal post core in a full ceramic crown restoration.Methods The color of full ceramic crowns on gold and Nickel-Chrome post cores was compared with the color of the same crowns on tooth colored post cores. Different try-in pastes were used to imitate the influence of a composite cementation on the color of different restorative combinations. The majority of patients could not detect any color difference less than △E 1.8 between the two ceramic samples. So, △E 1.8 was taken as the objective evaluative criterion for the evaluation of color matching and patients＇ satisfaction. Results When the Empress 2 crown was combined with the gold alloy post core, the color of the resulting material was similar to that of a glass fiber reinforced resin post core （△E = 0.3）. The gold alloy post core and the try-in paste did not show a perceptible color change in the full ceramic crowns, which indicated that the color of the crowns might not be susceptible to change between lab and clinic as well as during the process of composite cementation. Without an opaque covering the Ni-Cr post core would cause an unacceptable color effect on the crown （△E = 2.0）, but with opaque covering, the color effect became more clinically satisfactory （△E = 1.8）. Conclusions It may be possible to apply a gold alloy post core in the Empress 2 full ceramic crown restoration when necessary. If a non-extractible Ni-Cr post core exists in the root canal, it might be possible to restore the tooth with an Empress 2 crown after covering the labial surface of the core with one layer of opaque resin cement.

关键词： color difference ceramic crown post core try-in paste

Wear Behavior of a NiCr/AgVO_3 Self-Lubricating Composite

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Acta Metallurgica Sinica(English Letters) 2013年第4期26卷 435-440页

作者： Wenting ZHANG Lingzhong DU Hao lan Chuanbing HUANG Weigang ZHANG State Key Laboratory of Multi-phase Complex Systems Institute of Process EngineeringChinese Academy of Sciences University of Chinese Academy of Sciences

NiCr/AgVO3 self-lubricating composite was prepared by powder cold-pressed method with the NiCr alloy as the matrix and 10 wt.% additive of AgVO3 as solid lubricant. The AgVO3 additive powder was synthesized by the precipitation method which exhibits a melting point of 460℃. Microstructure, phase composition and thermal properties of the AgVO3 powder, as well as the composite of NiCr/AgVO3 were analyzed using scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, X-ray diffraction （XRD） and differential scanning calorimeter （DSC）. The friction and wear behavior of the specimens from room temperature （R.T.） to 800℃ was evaluated using a ball-on-disk tribometer and 3D white light interference （WLI）. The results showed that the friction coefficient of this material under atmosphere decreases with temperature increasing from R.T. to 800 ~C. However, the wear rate firstly increases from R.T. to 200℃, almost remains stable from 200℃ to 600℃, and then decreases with further increasing the temperature up to 800 ℃. It is also found that the prepared composite materials show a better frictional behavior than NiCr alloy over the whole range of temperatures, which is mainly attributed to solid lubrication of AgVO3 exhibiting a lamella-slip structure at temperatures below 460℃ and forms liquid-film at elevated temperatures above the melting point.

关键词： Silver vanadate (AgVO3) NiCr alloy Solid lubricant Tribological property

Oxidative Molecular Layer Deposition Tailoring Eco-Mimetic Nanoarchitecture to Manipulate Electromagnetic Attenuation and Self-Powered Energy Conversion

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Nano-Micro Letters 2023年第9期15卷 224-237页

作者： Jin-Cheng Shu Yan-lan Zhang Yong Qin Mao-Sheng Cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081People’s Republic of China Institute of Coal Chemistry State Key Laboratory of Coal ConversionChinese Academy of Sciences27 Taoyuan South RdTaiyuan 030001ShanxiPeople’s Republic of China

Advanced electromagnetic devices,as the pillars of the intelligent age,are setting off a grand transformation,redefining the structure of society to present pluralism and ***,the bombardment of electromagnetic radiation on society is also increasingly serious along with the growing popularity of"Big Data".Herein,drawing wisdom and inspiration from nature,an eco-mimetic nanoarchitecture is constructed for the first time,highly integrating the advantages of multiple components and structures to exhibit excellent electromagnetic *** electromagnetic properties and internal energy conversion can be flexibly regulated by tailoring microstructure with oxidative molecular layer deposition(oMLD),providing a new cognition to frequency-selective microwave *** optimal reflection loss reaches≈−58 dB,and the absorption frequency can be shifted from high frequency to low frequency by increasing the number of oMLD ***,a novel electromagnetic absorption surface is designed to enable ultra-wideband absorption,covering almost the entire K and Ka *** importantly,an ingenious self-powered device is constructed using the eco-mimetic nanoarchitecture,which can convert electromagnetic radiation into electric energy for *** work offers a new insight into electromagnetic protection and waste energy recycling,presenting a broad application prospect in radar stealth,information communication,aerospace engineering,etc.

关键词： Oxidative molecular layer deposition Eco-mimetic nanoarchitecture Microwave absorption Electromagnetic attenuation Self-powered energy conversion device

电针对急性心肌梗死大鼠心肌电重构的影响及其机制研究

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针刺研究 2024年第2期49卷 155-163页

作者：萨喆燕潘晓华朱小香兰彩莲万隆罗来许金森福建省中医药科学院经络研究所福建省经络感传重点实验室福州350003

目的:探讨电针“内关”通过增强瞬时外向钾电流(Ito)改善急性心肌梗死大鼠心肌电重构的作用机制。方法:雄性SD大鼠随机分成对照组、模型组和电针组,每组10只。采用皮下注射异丙肾上腺素(85 mg/kg)诱导急性心肌梗死模型。电针组造模24 h... 详细信息

目的:探讨电针“内关”通过增强瞬时外向钾电流(Ito)改善急性心肌梗死大鼠心肌电重构的作用机制。方法:雄性SD大鼠随机分成对照组、模型组和电针组,每组10只。采用皮下注射异丙肾上腺素(85 mg/kg)诱导急性心肌梗死模型。电针组造模24 h后电针左侧“内关”,每次20 min,每日1次,连续5 d。TTC染色观察心肌坏死情况;HE染色观察心肌组织病理形态、测量心肌细胞横截面积;心电图记录ST段高度、QT间期(QT)、校正QT间期(QTc),计算QT间期离散率(QTd)和校正QT间期离散率(QTcd);RNA测序法检测心肌组织钾离子通道相关基因表达差异;实时荧光定量PCR法和Western blot法分别检测心肌组织Kchip2、Kv4.2的mRNA和蛋白表达。结果:TTC染色可见对照组心肌呈红色,模型组大鼠心肌大部分呈白色缺血样改变,电针组仅见心尖处心肌组织呈白色。与对照组比较,模型组大鼠心肌细胞横截面积显著增大(P<0.01),ST段显著抬高(P<0.01),QT、QTc、QTd和QTcd均显著增加(P<0.05,P<0.01);与模型组比较,电针组大鼠心肌细胞横截面积显著减小(P<0.01),ST段显著下降(P<0.01),QT、QTc、QTcd和QTd均显著减少(P<0.01,P<0.05)。RNA测序共筛选出20个3组共同表达的钾离子通道相关基因,电针组与模型组比较,其中Kchip2上调差异倍数最大。与对照组比较,模型组大鼠心肌组织Kchip2、Kv4.2 mRNA和蛋白表达均显著降低(P<0.01,P<0.05);与模型组比较,电针组大鼠心肌组织Kchip2、Kv4.2 mRNA和蛋白表达均显著升高(P<0.01,P<0.05)。结论:电针可改善心肌梗死大鼠心肌电重构,其机制可能与增加Ito主要成分Kchip2、Kv4.2表达有关。

关键词：电针心肌梗死心肌电重构瞬时外向钾电流

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基于语用交互的跨目标立场检测

计算机工程与设计 2024年第8期45卷 2513-2519页

作者：任科兰张明书魏彬姜文闫法成武警工程大学密码工程学院陕西西安710086 武警工程大学网络与信息安全武警部队重点实验室陕西西安710086

针对缺乏足够的带标注意见数据、跨目标立场检测结果不佳且可解释性弱等问题,提出一种基于语用交互(pragmatic interaction graph convolution, PIGCN)的跨目标立场检测模型。考虑情感与立场在语义上的耦合关系,利用交互式图卷积神经网... 详细信息

针对缺乏足够的带标注意见数据、跨目标立场检测结果不佳且可解释性弱等问题,提出一种基于语用交互(pragmatic interaction graph convolution, PIGCN)的跨目标立场检测模型。考虑情感与立场在语义上的耦合关系,利用交互式图卷积神经网络(graphical convolutional network, GCN),增量式聚合单词在不同目标之间语用信息的相互作用,缓解目标间的信息孤岛问题。实验结果表明,该模型在平均F1值上达到了53.4%,优于基准模型,具有更好的可扩展性和适应性,在提升模型可解释性方面具有潜力。

关键词：跨目标立场检测图卷积神经网络语用交互词级粒度情感词汇可解释性依存图