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基于自组织特征映射聚类的协同过滤推荐算法

天津大学学报 2006年第B6期39卷 279-282页

作者：高琳琦李从东天津大学管理学院

个性化推荐系统是电子商务系统的一个重要研究内容,计算顾客之间的相似性或顾客聚类是产生良好推荐的关键．通过分析个性化推荐的应用特征,即顾客评分数据稀疏及其影响；在开放的电子商务环境中,新顾客不断加入和顾客偏好的迁移,使顾客... 详细信息

个性化推荐系统是电子商务系统的一个重要研究内容,计算顾客之间的相似性或顾客聚类是产生良好推荐的关键．通过分析个性化推荐的应用特征,即顾客评分数据稀疏及其影响；在开放的电子商务环境中,新顾客不断加入和顾客偏好的迁移,使顾客簇不断发生变化,提出了一种基于自组织特征映射聚类的协同过滤推荐算法,对高堆稀疏的样本进行动态聚类．它具有下列特点：①在自组织特征映射聚类中,引入抑制函数,使其能够适应顾客评分数据的稀疏性；②设置神经元的分裂和合并过程,使其能够满足顾客聚类的动态变化．通过实验分析,表明该算法能够适应顾客评分数据稀疏和顾客聚类的动态变化特征,从而提高推荐质量．

关键词：协同过滤推荐算法聚类分析自组织特征映射

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m序列扩频CDMA系统与混沌扩频CDMA系统在Rayleigh选择性衰落信道下的性能比较

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西南师范大学学报（自然科学版） 2002年第5期27卷 718-721页

作者：魏牧王琳西南师范大学电子与信息工程系重庆400715 重庆邮电学院通信与信息学院重庆400065

对Logistic映射的混沌序列作为扩频序列构成的混沌扩频CDMA系统与传统的m序列扩频CDMA系统进行了对比研究 ,并且对其二者在Rayleigh选择性衰落信道下的性能在SPW上进行了仿真、分析 ,具有重要实际意义 .

关键词： m序列扩频CDMA系统 Rayleigh选择性衰落信道性能比较瑞利选择性衰落信道宏蜂窝误码率混沌扩频CDMA系统 Logistic映射

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The Gamma Fuzzy Reliability Design of Vehicle parts

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The Gamma Fuzzy Reliability Design of Vehicle parts

Ultrathin curved PdNiRu nanosheets as bifunctional catalysts for oxygen reduction and ethylene glycol oxidation

2.09中国控制与决策会议

作者： Tie wang~1,Gaonan wang~2.Jianyang {2.~3 1.school of Vehicle,Shenyang Ligong university,Shenyang 110168,china. 2.school of Mechanical engineering,Tsinghua university,Beijing 100084,china. 3.The first affiliated hospital,china Medical university,Shenyang 110001,china

With considering lightening and safety of strength,integrations of both distribution’s density and function’s density,the normal fussy reliability formulas about vehicle parts that forces,strengths are gamma distribution and subordinate is parabola of exponential k was gotten;First integral change was achieved according to initial data and function imported and extent of integrated,second this number result with VB program in the computer was achieved by using middle-points integral calculus and romberg integration. This program can be used in design of vehicle parts for rising up level of design.

关键词： Vehicle parts Reliability design Gamma distribution Fussy mathematics

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Nano Research 2024年第5期17卷 3777-3784页

作者： Xianzeng Li Tingyu Lu Huan Pang Mingyi Zhang Dongdong Xu lin Xu Min Han Jun Yang Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Center of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Fujian Cross Strait Institute of Flexible electronics(Future Technology) Fujian Normal UniversityFuzhou 350117China State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China State Key Laboratory of Coordination Chemistry Nanjing UniversityNanjing 210023China school of Chemistry and Chemical engineering Yangzhou UniversityYangzhou 225009China Key Laboratory for Photonic and electronic Bandgap Materials Ministry of EducationSchool of Physics and Electronic EngineeringHarbin Normal UniversityHarbin 150025China

Pd-based metallic nanosheets with advanced physicochemical properties have been widely prepared and employed in various electrocatalytic ***,few concerns were focused on their multiple performances in different ***,highly curved and ultrathin PdNiRu nanosheets(NSs)are developed by facile wet-chemistry strategy and exhibit excellent electrocatalytic performance toward both oxygen reduction reaction(ORR)and ethylene glycol oxidation reaction(EGOR).Owing to the synergistically structural(e.g.,ultrathin,curved,defects/steps-rich)and compositional(ternary alloy)advantages,PdNiRu NSs exhibited enhanced ORR and EGOR specific/mass activities and better stability/durability than control *** specific activity(5.52.mA·cm^(−2.)and mass activity(1.13 A·mg_(Pd)^(−1))of the PdNiRu NSs in ORR are 4.8 and 3.4 times as the ones of commercial Pt/C,*** mass activity of PdNiRu NSs(3.86 A·mg_(Pd)^(−1))in EGOR is 2.6 times as commercial Pd/C(1.51 A·mg_(Pd)^(−1)).This study is helpful for the development of desired electrocatalysts with multi-functional application in practical fuel cells.

关键词： ultrathin nanosheets noble metal electrocatalysts bifunctional

Cs_(2.(Ag∶Cu)BiBr_(6)双钙钛矿太阳能电池

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发光学报 2024年第4期45卷 662-670页

作者：曹士双王宝宁李林哈尔滨师范大学物理与电子工程学院光电带隙材料教育部重点实验室黑龙江哈尔滨150000

采用水热法合成了Cu^(+)掺杂的Cs_(2.AgBiBr_(6)双钙钛矿并基于其制备了太阳能电池。通过紫外-可见光吸收光谱、荧光发射光谱、X射线光电子能谱、单色光量子效率光谱及光电流-电压曲线等手段对其光电性能进行探究。研究发现,Cu^(+)掺杂... 详细信息

采用水热法合成了Cu^(+)掺杂的Cs_(2.AgBiBr_(6)双钙钛矿并基于其制备了太阳能电池。通过紫外-可见光吸收光谱、荧光发射光谱、X射线光电子能谱、单色光量子效率光谱及光电流-电压曲线等手段对其光电性能进行探究。研究发现,Cu^(+)掺杂能够显著增强Cs_(2.AgBiBr_(6)粉末样品的光学吸收,但对于薄膜样品几乎没有效果,这是由于Cu相双钙钛矿在溶于二甲基亚砜的过程中会发生分解。实验结果表明,当Cu^(+)掺杂量较低时,太阳能电池的光电转化效率显著提升,这是由于Cu^(+)掺杂对Cs_(2.AgBiBr_(6)薄膜结晶过程的调控作用,微量Cu^(+)掺杂能够显著降低钙钛矿薄膜的缺陷态密度。最终,基于Cu^(+)掺杂的太阳能电池获得了最高1.93%的能量转化效率。

关键词： Cs2.gBiBr6 Cu+掺杂太阳能电池钙钛矿

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Visual test paper based on Au/δ-MnO_(2. hollow nanosphere oxidase-like activity regulation using hexavalent chromium as a smart switch

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Rare Metals 2024年第2期43卷 711-722页

作者： Wen-Chang Zhuang Hai-Yue Zhang Zhen-Yang Chen Wen-Jing Cheng Wei-Dan Na Zhao Li lin Tian school of Materials and Chemical engineering Xuzhou University of TechnologyXuzhou221018China school of Chemistry and Environmental Science Yili Normal UniversityYining835000China

Paper-based sensing platform is a point of need analytical toolkit for safety ***,the sensitivity,specificity,and simplicity are still ***,we report a novel strategy(Au/δ-MnO_(2. hollow nanosphere and 3,3′,5,5′-tetramethylbenzidine(TMB)induced test strips for signal-on detection)that can be utilized for hexavalent chromium(Cr^(6+))***,Cr^(6+)(CrO_(4)^(2.)) as a smart switch can remarkably enhance the oxidase-like activity of Au/δ-MnO_(2. hollow *** presence of Cr^(6+) can regulate the surface electronic redistribution of Au/δ-MnO_(2. and adjust the geometric configuration,which leads to the improvement in oxidase-like activity of Au/δ-MnO_(2..As a proof-of-concept application,a visual paper-based sensing platform of Cr^(6+) along with quantitative analysis by the test strips was successfully *** paper-based sensing platform exhibits a linear range with excellent selectivity for other interfering substances and lower limit of detection of 0.09μmol·L^(−1),providing a promising toolkit at-home Cr^(6+) measurement and environmental monitoring.

关键词： Point of need Colorimetric biosensing platform Au/δ-MnO_(2. hollow nanosphere Test strip Cr^(6+)

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The manipulation of rectifying contact of Co and nitrogen-doped carbon hierarchical superstructures toward high-performance oxygen reduction reaction

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Carbon Energy 2024年第9期6卷 338-349页

作者： Jing Li Tingyu Lu Yu Fang Guangyao Zhou Mingyi Zhang Huan Pang Jun Yang Yawen Tang lin Xu Jiangsu Key Laboratory of New Power Batteries School of Chemistry and Materials ScienceJiangsu Collaborative Innovation Center of Biomedical Functional MaterialsNanjing Normal UniversityNanjingJiangsuChina College of Science Jinling Institute of TechnologyNanjingJiangsuChina Key Laboratory for Photonic and electronic Bandgap Materials Ministry of EducationSchool of Physics and Electronic EngineeringHarbin Normal UniversityHarbinHeilongjiangChina school of Chemistry and Chemical engineering Yangzhou UniversityYangzhouJiangsuChina State Key Laboratory of Multiphase Complex Systems Center of MesoscienceInstitute of Process EngineeringChinese Academy of SciencesBeijingChina

Rational design and construction of oxygen reduction reaction(ORR)electrocatalysts with high activity,good stability,and low price are essential for the practical applications of renewable energy conversion devices,such as metal-air *** modification through constructing metal/semiconductor Schottky heterointerface represents a powerful strategy to enhance the electrochemical ***,we demonstrate a concept of Schottky electrocatalyst composed of uniform Co nanoparticles in situ anchored on the carbon nanotubes aligned on the carbon nanosheets(denoted as Co@N-CNTs/NSs hereafter)toward *** experimental findings and theoretical simulation testify that the rectifying contact could impel the voluntary electron flow from Co to N-CNTs/NSs and create an internal electric field,thereby boosting the electron transfer rate and improving the intrinsic *** a consequence,the Co@N-CNTs/NSs deliver outstanding ORR activity,impressive long-term durability,excellent methanol tolerance,and good performance as the air-cathode in the Zn-air *** design concept of Schottky contact may provide the innovational inspirations for the synthesis of advanced catalysts in sustainable energy conversion fields.

关键词： Co-based electrocatalysts oxygen reduction reaction rectifying contact Zn-air batteries