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ORDINAL REGRESSION FOR INFORMATION RETRIEVAL

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Journal of Electronics(China) 2008年第1期25卷 120-124页

作者： Qi Haoliang Li Sheng gao jianfeng Han Zhongyuan Xia Xinsong Ministry of Education-Microsoft Key Laboratory of Natural Language Processing and Speech Harbin Institute of Technology Harbin 150001 China Microsoft Research One-Microsoft Way Redmond WA 98052 USA Heilongjiang Institute of Technology Harbin 150001 China Peking University Beijing 100871 China

This letter presents a new discriminative model for Information Retrieval (IR), referred to as Ordinal Regression Model (ORM). ORM is different from most existing models in that it views IR as ordinal regression problem (i.e. ranking problem) instead of binary classification. It is noted that the task of IR is to rank documents according to the user information needed, so IR can be viewed as ordinal regression problem. Two parameter learning algorithms for ORM are presented. One is a perceptron-based algorithm. The other is the ranking Support Vector Machine (SVM). The effec- tiveness of the proposed approach has been evaluated on the task of ad hoc retrieval using three English Text REtrieval Conference (TREC) sets and two Chinese TREC sets. Results show that ORM sig- nificantly outperforms the state-of-the-art language model approaches and OKAPI system in all test sets; and it is more appropriate to view IR as ordinal regression other than binary classification.

关键词： Information Retrieval (IR) Ordinal Regression Perceptron Ranking Support Vector Machine (SVM)

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塑料类汽车零部件仿真模拟技术研究进展

工程塑料应用 2024年第6期52卷 182-186,192页

作者：高健峰上海亚大汽车塑料制品有限公司上海201708

从选材与结构优化、成型工艺优化和性能测试仿真方面,综述了近几年国内在塑料类汽车零部件仿真模拟技术方面的研究进展情况。其中,在成型工艺优化方面,重点总结了BP神经网络、灰色关联等算法在注射成型工艺优化方面的应用情况,同时也介... 详细信息

从选材与结构优化、成型工艺优化和性能测试仿真方面,综述了近几年国内在塑料类汽车零部件仿真模拟技术方面的研究进展情况。其中,在成型工艺优化方面,重点总结了BP神经网络、灰色关联等算法在注射成型工艺优化方面的应用情况,同时也介绍了多种算法联合仿真的研究进展情况。最后对应用于塑料类汽车零部件的仿真模拟技术发展方向进行了展望。

关键词：汽车零部件塑料模拟仿真成型工艺优化

Synergistic promotion strategy of “dual-site” and “dual-path” to enhance the C–C coupling between CO2 and HCHO driven by photoelectrocatalysis

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Journal of Energy Chemistry 2025年第1期100卷 39-49页

作者： Hongqiang Yang jianfeng Zheng Guoyu Wang Yifei gao Yatao Yang Jia Li Xiaojin Han Yan Cui Zhanggen Huang National Key Laboratory of High Efficiency and Low Carbon Utilization of Coal Institute of Coal Chemistry Chinese Academy of Science University of Chinese Academy of Science Shenyang University of Chemical Technology

Photoelectrocatalytic coupling CO2and volatile organic compounds （VOCs） is a promising green strategy for the synergistic conversion of the two carbon-containing resources to *** catalytic efficiency is always at the mercy of chemical inertness of CO2and the competitive hydrogen evolution of ***,a modified g-C3N4/ZnAl-LDH Z-scheme heterojunction catalyst with dual reaction site was rationally designed and precisely *** Faraday efficiency of ethanol reached 68.67%with a corresponding formation rate of 227.3μmol *** revealed by in-situ characterizations and density functional theory calculations,CO2and HCHO were absorbed at Zn site and N site,***,*CO generated from CO2and HCHO was converted to*CH3O and*CHO on the dual-active-site *** detailed reaction mechanism experiments indicated that C–C coupling only occurred between*CO and*CH3O in electrocatalysis *** from the“*CO+*CH3O”path,another“*CO+*CHO”coupling path was also detected in photoelectrocatalytic *** selectivity of ethanol was significantly enhanced due to the synthesis of dual-site catalyst and the dual-path coupling path between CO2and HCHO simultaneously driven by light and electricity.

关键词： Photoelectrocatalysis Z-scheme C–C coupling Ethanol

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感知器在语言模型训练中的应用

计算机研究与发展 2006年第2期43卷 260-267页

作者：于浩步丰林高剑峰上海交通大学计算机科学与工程系上海200030 微软亚洲研究院北京100080

感知器（perceptron）是神经网络模型中的一种，它可以通过监督学习（supervised learning）的方法建立模式识别的能力．将感知器应用到语言模型的训练中，实现了感知器的两种不同训练规则以及多种特征权值计算方法，讨论了不同的训练... 详细信息

感知器（perceptron）是神经网络模型中的一种，它可以通过监督学习（supervised learning）的方法建立模式识别的能力．将感知器应用到语言模型的训练中，实现了感知器的两种不同训练规则以及多种特征权值计算方法，讨论了不同的训练参数对训练效果的影响．在训练之前，使用了一种基于经验风险最小化（empirical risk minimization，ERM）的特征选择算法确定特征集合．感知器训练之后的语言模型在日文假名到汉字（kana-kanji）的转换中进行评估．通过实验对比了感知器的两种训练规则以及变形算法的性能，同时发现通过感知器训练的模型比传统模型（N-gram）在性能上有了很大的提高，使相对错误率下降了15％～20％．

关键词：感知器语言模型经验风险最小化

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我国粮食生产和加工对饲料加工业的影响

中国粮油学报 2006年第3期21卷 445-448页

作者：高建峰国家粮食储备局武汉科学研究设计院武汉430079

论述了3大粮食作物及其加工副产品在饲料加工业中的应用,粮食生产和加工对饲料加工业的影响。粮食生产和加工业的稳定和健康发展,为饲料加工业提供优质和价格稳定的原料,是饲料加工业快速发展的基础之一。

关键词：粮食生产粮食加工饲料加工影响

A 2-26GHz MMIC POWER AMPLIFIER WITH LOW NOISE FIGURE

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A 2-26GHz MMIC POWER AMPLIFIER WITH LOW NOISE FIGURE

Mechanism investigation of PtPd decorated Zn_(0.5)Cd_(0.5)S nanorods with efficient photocatalytic hydrogen production combining with kinetics and thermodynamics

2000 2nd International Conference on Microwave and Millimeter Wave Technology

作者： Chen Xuejun Chen Xiaojian gao jianfeng Lin Jinting Nanjing Electronic Devices Institute

＜正＞This paper describes the modeling,design,fabrication and performance of a monolithic 2～26 GHz MMIC PHEMT power amplifier with low noise *** using distributed circuit and series gate capacitors,the measured gain is 6.5±0.5dB with both in and out VSWR less than 2.0 in the broad band,and the measured output power is over 300 mW with 3.5～5.5dB noise figure in 2～20 GHz frequency *** amplifier is truly monolithic, with all matching and biasing and DC block circuitry included on the *** finished chip size is 3.2mm×1.275mm×0.1mm.

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来源： cnki会议评论

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Chinese Journal of Catalysis 2021年第10期42卷 1677-1688页

作者： Linhe Zhang Fudong Zhang Huaqing Xue jianfeng gao Yong Peng Weiyu Song Lei Ge State Key Laboratory of Heavy Oil Processing College of New Energy and MaterialsChina University of Petroleum BeijingBeijing 102249China Department of New Energy Research Institute of Petroleum Exploration&DevelopmentPetroChinaBeijing 100083China Department of Applied Chemistry College of ScienceChina University of Petroleum BeijingBeijing 102249China

Different components of PtPd bimetallic cocatalysts modified Zn_(0.5)Cd_(0.5)S nanorods have already been designed and prepared in this *** obtained hybrid photocatalysts were tested and characterized by XPS,ICP-OES and UV-Vis spectra,TEM and EDX *** characterizations can prove the formation of PtPd bimetallic alloy particles in hybrid *** visible light illumination,an outstanding hydrogen producing rate of 9.689mmol·g^(-1)·h^(-1) and a high AQY efficiency up to 10.43%at 420 nm are achieved in this *** addition,thermodynamics(DFT calculations)and kinetics(Photoluminescence emission,photocurrent responses,electrochemical impedance spectroscopy and surface photovoltage spectra)investigations illustrate that PtPd bimetallic alloy has similar catalytic thermodynamic properties to Pt,which can greatly boost the charge separation and speed up the charge transfer,and decrease the activation energy of H2 ***,the calculation data suggests that Pt is thermodynamically favorable,while PtPd alloy is kinetically beneficial to H_(2)production,which can be ascribed to the higher activity of PtPd/Zn_(0.5)Cd_(0.5)S than Pt/Zn_(0.5)Cd_(0.5)*** work can propose a fresh perspective for preparing high efficiency hybrid photocatalysts.

关键词： PtPd alloy Zn_(0.5)Cd_(0.5)S nanorods Photocatalytic hydrogen evolution DFT calculation

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微米级铜-银双金属粉镀层结构及其抗氧化性

物理化学学报 2000年第4期16卷 366-369页

作者：高保娇高建峰蒋红梅张忠兴华北工学院化工系太原030051

The correlation of plating structure with the antioxygenation of micro Cu-Ag bimetallic powder was studied by SEM、XRD、TG and other *** was found that copper powder plated with silver having an interspersion structure posesses antioxygenation at normal atmospheric temperature as surface Ag content reaches above 15.22%,the temperature of oxidation resistance varies with the surface Ag *** greater the surface Ag content is,the higher the temperature of antioxygenation for bimetalic powder with the plating interspersion *** copper powder plated by silver with full packaging structure can not be oxidized even at

关键词：铜-银双金属粉表层结构抗氧化性镀银铜粉

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莫莫格湿地景观变化及对白鹤生境的影响

野生动物学报 2021年第1期42卷 106-113页

作者：徐睿泽高健峰中国地质大学(北京) 信息工程学院北京100083

明确白鹤的生境需求,对白鹤种群保护具有重要参考价值。因此,本文选取不同年份的4幅莫莫格湿地的遥感影像,利用ENVI 5.3软件基于SVM分类算法对该区域进行土地覆盖分类,利用FRAGSTATS 4.2软件对莫莫格湿地白鹤生境进行景观格局动态分析,... 详细信息

明确白鹤的生境需求,对白鹤种群保护具有重要参考价值。因此,本文选取不同年份的4幅莫莫格湿地的遥感影像,利用ENVI 5.3软件基于SVM分类算法对该区域进行土地覆盖分类,利用FRAGSTATS 4.2软件对莫莫格湿地白鹤生境进行景观格局动态分析,分别从时空尺度对比该区域白鹤生境的变化情况及其对白鹤种群的影响。研究结果表明,4个年份土地分类的总体精度均大于85%,分类结果满足研究需求;该保护区湿地面积从500.4 km2增长至628.4 km2,其中挺水植物带及软泥区是吸引迁徙白鹤聚集的主要地带;湿地的PAFRAC从1.525降低至1.475,表明湿地破碎度缓慢增加、形状趋于简单化,景观配置改变了白鹤在生境选择时的空间分布结构;LPI仅减少0.22%,CONTAG从33.8升高至34.4,说明景观系统斑块集聚度高、连通性好,为白鹤种群提供广阔的生境。基于研究结果发现莫莫格湿作为白鹤迁徙途中的驿站,因其逐年优化的生态结构而为白鹤种群的稳定迁徙提供重要保障。

关键词：湿地生态系统土地覆盖景观格局白鹤