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概念指导的关联规则的挖掘

计算机研究与发展 1999年第9期36卷 1092-1096页

作者：程继华施鹏飞上海交通大学图像处理与模式识别研究所上海200030

关联规则是数据依赖关系的有效描述方法，是知识发现研究的重要内容．传统的关联规则挖掘算法缺少挖掘的针对性，挖掘速度慢，挖掘结果难于理解，挖掘结果的数量巨大，需要进行大量的筛选以便抽取出有用规则．文中提出了将概念融入挖掘... 详细信息

关联规则是数据依赖关系的有效描述方法，是知识发现研究的重要内容．传统的关联规则挖掘算法缺少挖掘的针对性，挖掘速度慢，挖掘结果难于理解，挖掘结果的数量巨大，需要进行大量的筛选以便抽取出有用规则．文中提出了将概念融入挖掘过程中，提高挖掘的效率和挖掘的针对性的方法，给出了概念指导的关联规则挖掘算法ＣＧＡＲＭ和大数据库中概念的交互式生成方法．算法ＣＧＡＲＭ是对基于分类的挖掘算法的拓展．实验结果表明，算法ＣＧＡＲＭ提高了挖掘结果的有趣性，挖掘速率比传统的多层次关联规则挖掘算法Ｃｕｍｕｌａｔｅ

关键词：知识发现数据挖掘关联规则概念数据库

An observed nocturnal ozone transport event in the Sichuan Basin,Southwestern China

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Journal of Environmental Sciences 2024年第4期138卷 10-18页

作者： Ruyue Guo Guangming shi Dan Zhang Yang Chen Chao peng Chongzhi Zhai Fumo Yang Department of Environmental Science and Engineering Sichuan UniversityChengdu 610065China College of Carbon Neutrality Future Technology Sichuan UniversityChengdu 610065China National Engineering Research Center on Flue Gas Desulfurization Chengdu 610065China Chongqing Academy of Eco-Environmental Science Chongqing 401147China Research Center for Atmospheric Environment Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China Key Laboratory for Urban Atmospheric Environment Integrated Observation&Pollution Prevention and Control of Chongqing Chongqing 401147China

The ozone(O_(3))pollution in China drew lots of attention in recent years,and the Sichuan Basin(SCB)was one of the regions confronting worsening O_(3)pollution *** previous studies have shown that regional transport is an important contributor to O_(3)***,very few features of the O_(3)profile during transport have been reported,especially in the border regions between different administrative *** this study,we conducted tethered balloon soundings in SCB during the summer of 2020 and captured a nocturnal O_(3)transport event during the ***,the O_(3)transport occurred in the bottom of the residual layer,between 200 and 500 m above ground ***,the transport pathway was directed from southeast to northwest based on the analysis of the wind field and air mass *** effect of transport in the residual layer on the surface O_(3)concentration was related to the spatial distribution of O_(3).For cities with high O_(3)concentrations in the upwind region,the transport process would bring clean air masses and abate *** downwind lightly polluted cities,the transport process would slow down the decreasing or even increase the surface O_(3)concentration during the *** provided observational facts on the profile features of a transboundary O_(3)transport event between two provincial administrative divisions,which implicated the importance of joint prevention and control ***,the sounding parameters were limited and the quantitative analysis was preliminary,more integrated,and thorough studies of this topic were called for in the future.

关键词： Ozone Sichuan basin Transport event Vertical profile

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一种有效的用于数据挖掘的动态概念聚类算法

软件学报 2001年第4期12卷 582-591页

作者：郭建生赵奕施鹏飞上海交通大学图像处理与模式识别研究所上海200030

概念聚类适用于领域知识不完整或领域知识缺乏时的数据挖掘任务 .定义了一种基于语义的距离判定函数 ,结合领域知识对连续属性值进行概念化处理 ,对于用分类属性和数值属性混合描述数据对象的情况 ,提出了一种动态概念聚类算法 DDCA(dom... 详细信息

概念聚类适用于领域知识不完整或领域知识缺乏时的数据挖掘任务 .定义了一种基于语义的距离判定函数 ,结合领域知识对连续属性值进行概念化处理 ,对于用分类属性和数值属性混合描述数据对象的情况 ,提出了一种动态概念聚类算法 DDCA(domain- based dynamic clustering algorithm) .该算法能够自动确定聚类数目 ,依据聚类内部属性值的频繁程度修正聚类中心 ,通过概念归纳处理 ,用概念合取表达式解释聚类输出 .研究表明 ,基于语义距离判定函数和基于领域知识的动态概念聚类的算法 DDCA是有效的 .

关键词：数据挖掘领域知识动态概念聚类算法数据对象数据集合数据库

Ultracompact silicon on-chip polarization controller

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Photonics Research 2024年第2期12卷 183-193页

作者： WEIKE ZHAO YINGYING peng MINGYU ZHU RUORAN LIU XIAOLONG HU YAOCHENG shi DAOXIN DAI State Key Laboratory for Modern Optical Instrumentation Center for Optical&Electromagnetic ResearchCollege of Optical Science and EngineeringInternational Research Center for Advanced PhotonicsZhejiang UniversityZijingang CampusHangzhou 310058China School of Precision Instrument and Optoelectronic Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Optoelectronic Information Science and Technology Ministry of EducationTianjin 300072China Ningbo Research Institute Zhejiang UniversityNingbo 315100China

On-chip polarization controllers are extremely important for various optical *** this paper,a compact and robust silicon-based on-chip polarization controller is proposed and demonstrated by integrating a special polarization converter and phase *** special polarization converter consists of a 1×1 Mach–Zehnder interferometer with two polarization-dependent mode converters at the input/output *** light with an arbitrary state of polarization(SOP)is launched into the chip,the TE_(0)and TM_(0)modes are simultaneously *** polarization extinction ratio(PER)and the phase difference for the TE_(0)∕TM_(0)modes are tuned by controlling the first phase shifter,the polarization converter,and the second phase *** a result,one can reconstruct the light SOP at the output *** fabricated polarization controller,as compact as~150μm×700μm,exhibits an excess loss of less than 1 dB and a record PER range of>54 dB for arbitrary input light beams in the wavelength range of 1530–1620 nm.

关键词： polarization SOP interferometer

LaNi_5型储氢合金表面修饰及其电化学性能研究

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无机化学学报 2005年第3期21卷 446-450页

作者：邓超史鹏飞张森曾佳哈尔滨工业大学应用化学系哈尔滨150001 哈尔滨工程大学化工学院哈尔滨150001

This paper presents a new method of surface modification on LaNi5 hydr ogen storage alloy. The hydrogen alloy was treated in the acid CuSO4 solution co ntaining HF. The effect of HF on surface state of alloy was studied and the elec trochemical properties of modified alloy were investigated. Electrochemical impe dance spectra (EIS) was also applied to analyze the resistance property of alloy electrode after modification. SEM and XRD results showed that HF had corrosive effect on hydrogen alloy, which help copper grain to precipitate on alloy surfac e. EIS analysis showed that modified alloy had lower contact resistance and elec trochemical polarization, which resulted in a higher conductivity and electroche mical activation. Electrochemical testing showed modified alloy had better activ ation behavior and excellent large current discharge ability. Thus it could well satisfy the requirement of the application as power sources on electric vehicle s.

关键词： LaNi5 HF 表面修饰 CuSO4 XRD EIS 电化学性能储氢合金 SEM

Spin effect on redox acceleration and regioselectivity in Fe-catalyzed alkyne hydrosilylation

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National Science Review 2024年第2期11卷 155-167页

作者： peng He Meng-Yang Hu Jin-Hong Li Tian-Zhang Qiao Yi-Lin Lu Shou-fei Zhu Frontiers Science Center for New Organic Matter State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

Iron catalysts are ideal transition metal catalysts because of the Earths abundant, cheap, biocompatible features of iron salts. Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations, a feature rarely found in noble metal catalysts. Unfortunately, little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts, which makes the development of iron catalysts a low efficient trial-and-error program. In this paper, a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis. Deep insight into the electronic structures of a set of well-defined open-shell active formal Fe(0) catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center's spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination, respectively,and the spin crossover is essential for this electron transfer process. The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions. These findings provide an important reference for understanding the effect of catalyst spin state on reaction. It is inspiring for the development of iron catalysts and other Earth-abundant metal catalysts, especially from the point of view of ligand development.

关键词： spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation

Ultra-robust informational metasurfaces based on spatial coherence structures engineering

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Light(Science & Applications) 2024年第7期13卷 1310-1319页

作者： Leixin Liu Wenwei Liu fei Wang Xiaofeng peng Duk-Yong Choi Hua Cheng Yangjian Cai Shuqi Chen Shandong Provincial Engineering and Technical Center of Light Manipulations Collaborative Innovation Center of Light Manipulation and ApplicationsShandong Provincial Key Laboratory of Optics and Photonic DeviceSchool of Physics and ElectronicsShandong Normal UniversityJinan 250014China. The Key Laboratory of Weak Light Nonlinear Photonics Ministry of EducationSchool of PhysicsSchool of Materials Science and EngineeringSmart Sensing Interdisciplinary Science CenterNankai UniversityTianjin 300071China. School of Physical Science and Technology Soochow UniversitySuzhou 215006China. Laser Physics Centre Research School of PhysicsAustralian National UniversityCanberraACT 2601Australia. The Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuanShanxi 030006China

Optical information transmission is vital in modern optics and photonics due to its concurrent and multi-dimensional nature,leading to tremendous applications such as optical microscopy,holography,and optical *** optical information transmission technologies suffer from bulky optical setup and information loss/crosstalk when meeting scatterers or obstacles in the light ***,we theoretically propose and experimentally realize the simultaneous manipulation of the coherence lengths and coherence structures of the light beams with the disordered *** ultra-robust optical information transmission and self-reconstruction can be realized by the generated partially coherent beam with modulated coherence structure even 93%of light is recklessly obstructed during light transmission,which brings new light to robust optical information transmission with a single *** method provides a generic principle for the generalized coherence manipulation on the photonic platform and displays a variety of functionalities advancing capabilities in optical information transmission such as meta-holography and imaging in disordered and perturbative media.

关键词： optics coherent holography

Revisiting the sodium-ion storage capability of hard carbon in carbonate-based electrolytes via a sodium-metal-free protocol

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Science China Chemistry 2024年第7期67卷 2240-2247页

作者： Gaopan Liu Yanbing Mo Jiawei Chen Yu peng Xiao Zhu fei Wang Xiaoli Dong Yongyao Xia Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New EnergyLaboratory of Advanced MaterialsFudan UniversityShanghai 200438China

Common evaluation methodology of sodium(Na)-containing two-electrode or three-electrode configurations overlooks the interference from highly reactive Na metal,leading to the underestimation or inconsistent performance of low-potential hard carbon(HC)***,the trap of Na metal was systematically investigated with or without applied current,uncovering its inadequacy as the reference or counter electrode in different configurations.A Na-metal-free three-electrode protocol is proposed for evaluating the actual Na^(+)-storage capability of the typical low-potential HC *** avoiding Na crosstalk and precisely controlling the working electrode's potential,the actual electrochemical performance of HC in the carbonate esterbased electrolyte can be recognized with high capacity of 222 mAh g^(-1)at 2 C and 113 mAh g^(-1)at 5 C,correcting the misunderstanding of the inferior performance of HC in coin-type half cells(68%and 50%undervaluation at 2 C and 5 C,respectively).The advanced protocol is expected to reduce misunderstandings or underestimation due to evaluation methods and to guide the development of high-performance battery materials.

关键词： highly reactive sodium potential drift carbonate ester sodium-metal-free protocol sodium storage capability

Tuning interface mechanism of FeCo alloy embedded N,S-codoped carbon substrate for rechargeable Zn-air battery

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Journal of Energy Chemistry 2024年第6期93卷 400-410,I0010页

作者： Hui Chang Lulu Zhao Shan Zhao Zong-Lin Liu peng-fei Wang Ying Xie Ting-Feng Yi School of Materials Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080HeilongjiangChina Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao 066004HebeiChina

The interface mechanism between catalyst and carbon substrate has been the focus of *** this paper,the FeCo alloy embedded N,S co-doped carbon substrate bifunctional catalyst(FeCo/S-NC)is obtained by a simple one-step pyrolysis *** experimental results and density functional theory(DFT)calculation show that the formation of FeCo alloy is conducive to promoting electron transfer,and the introduction of S atom can enhance the interaction between FeCo alloy and carbon substrate,thus inhibiting the migration and agglomeration of particles on the surface of carbon *** FeCo/SNC catalysts show outstanding performance for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).FeCo/S-NC shows a high half-wave potential(E_(1/2)=0.8823 V)for ORR and a low overpotential at 10 mA cm^(-2)(E_(j=10)=299 mV)for *** addition,compared with Pt/C+RuO_(2) assembled Zn-air battery(ZAB),the FeCo/S-NC assembled ZAB exhibits a larger power density(198.8 mW cm^(-2)),a higher specific capacity(786.1 mA h g_(zn)~(-1)),and ultra-stable cycle *** results confirm that the optimized composition and the interfacial interaction between catalyst and carbon substrate synergistically enhance the electrochemical performance.

关键词： FeCo alloy N S co-doped carbon DFT calculation Zn-air batteries Interfacial interaction