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应用机器学习加速新材料的研发

中国科学：物理学、力学、天文学 2018年第10期48卷 54-66页

作者：吴炜孙强北京大学工学院材料系北京100871 北京大学应用物理与技术研究中心北京100871

材料不仅是国民经济的基础,而且也是高新技术的载体.超越常规手段、应用新方法加速新材料的研发已成为全世界的研究热点.随着数据驱动方法取得的巨大成功,机器学习受到了日益高度的关注.它结合计算机科学、数据库理论、统计学、计算数... 详细信息

材料不仅是国民经济的基础,而且也是高新技术的载体.超越常规手段、应用新方法加速新材料的研发已成为全世界的研究热点.随着数据驱动方法取得的巨大成功,机器学习受到了日益高度的关注.它结合计算机科学、数据库理论、统计学、计算数学和工程学,不仅能展现出更快的计算速度和可靠的预测能力,大幅度提升材料计算效率,而且还能有效地处理一些难以运用传统模拟计算方法解决的体系和问题,这为研发具有特殊功能和特殊结构的新材料以满足日益提升的新技术的要求提供了契机.本文将简要概述机器学习的基本原理,介绍机器学习模型中的几种典型算法以及机器学习在新材料研究中的应用进展,并对机器学习在材料科学领域中的未来的发展前景做出展望.

关键词：新材料机器学习材料计算模拟

Analysis of Expressed Sequence Tags from Liver Tissue in Swine

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Agricultural Sciences in china 2002年第9期1卷 1050-1053页

作者： LI Ning, ZHAO Zhi-hui, LIU Zhao-Hang, ZHAO Xing-bo, LIAN Zhen-xing and WU Chang-xin(National Laboratory for Agro-biotechnology, china Agricultural university, {2. 100094 , P.R.china College of Animal Science and Technology, china Agricultural university , {2. 100094 , P. R . china ) National Laboratory for Agro-biotechnology China Agricultural University Beijing 100094 P. R. China College of Animal Science and Technology China Agricultural University Beijing 100094 P. R . China

In order to study the expression of function gene and its effect on metabolic control and other physiological function in liver, 438 expressed sequence tags (ESTs) were determined, which were from a cD-NA library of porcine liver tissue. The results showed that the nucleotide sequences of 186 ESTs have already presented in GenBank database, and 37 ESTs could be found the homology with human and other species, while the others were not identified. 45 full length insertion of the clones randomly isolated from cDNA library were also completely sequenced with different size, and the results showed that 19 of them were function-known genes, 11 had no open reading frame ( ORF )at all and 15 had ORF but the function were not elucidated yet.

关键词： Swine Liver cDNA library Expressed sequence tags(ESTs)

Spatio-Temporal Adaptive Super-Resolution Reconstruction Model Based on Zemike Moment for Spatial Video Sequences

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china Communications 2012年第12期9卷 93-107页

作者： Liang Meiyu Du Junping JangMyung Lee Liu Honggang Zhang Yun beijing Key Laboratory of Intelligent Telecommunication Software and Multimedia School of Computer Science Beijing University of Posts and Telecommunications Beijing 100876 P. R. China Department of Electronics Engineering Pusan Nation University Busan Korea

Video Super-Resolution （SR） reconstruction produces video sequences with High Resolution （HR） via the fusion of several Low-Resolution （LR） video frames. Traditional methods rely on the accurate estimation of subpixel motion, which constrains their applicability to video sequences with relatively simple motions such as global translation. We propose an efficient iterative spatio-temporal adaptive SR reconstruction model based on Zemike Moment （ZM）, which is effective for spatial video sequences with arbitrary motion. The model uses region correlation judgment and self-adaptive threshold strategies to improve the effect and time efficiency of the ZM-based SR method. This leads to better mining of non-local self-similarity and local structural regularity, and is robust to noise and rotation. An efficient iterative curvature-based interpolation scheme is introduced to obtain the initial HR estimation of each LR video frame. Experimental results both on spatial and standard video sequences demonstrate that the proposed method outperforms existing methods in terms of both subjective visual and objective quantitative evaluations, and greatly improves the time efficiency.

关键词： video super-resolution fuzzy registration scheme Zemike moment non-local self-similarity self-adaptive threshold

research on the SCS-CN initial abstraction ratio using rainfall-runoff event analysis in the Three Gorges Area,china

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Research on the SCS-CN initial abstraction ratio using rainf...

第五届中国青年生态学工作者学术研讨会

作者： Zhi-Hua Shi~(1,2. Li-Ding Chen~2.1 Key Lab of Subtropical Agriculture & Environment of Ministry of Agriculture,Huazhong Agricultural university,Wuhan 430070,PR china 2.State Key Laboratory of Urban and Regional Ecology,{2. Center for Eco-environmental Sciences,Chinese Academy of Sciences,P.O.Box 2.71,beijing 100085,PR china

The Soil Conservation Service Curve Number (SCS-CN) method is widely used for predicting direct runoff from *** ratio of initial abstraction(Ⅰa) to maximum potential retention (S) was assumed in its original development to be equal to 0.2.in SCS-CN *** constant initial abstraction ratio is the most ambiguous assumption and requires considerable *** objectives of this study were (1) to determine the initial abstraction ratio,in an experimental watershed in the Three Gorges Area of china,by analyzing measured rainfall-runoff events;(2. to compare the performance of the traditional and modifiedⅠa/S values with observed rainfall-runoff *** dataset consisted of 6 years of rainfall and runoff measurements from the experimental *** results indicated that theⅠa/S values,using event rainfall-runoff data, varied from 0.010 to 0.154,with a median of *** average initial abstraction ratio of the watershed was equal to 0.053,The standard SCS-CN method underestimates large runoff events, yielded a slope of the regression line of 0.559 and an intercept of *** modifiedⅠa/S value was about 0.05 that better predicted runoff depths with an R of 0.804 and a linear regression slope of *** also improved model efficiency coefficient (E) to 0.768 compared with 0.482.for traditionalⅠa/S *** Ia/S-adjusted SCS-CN method appears to be better appropriate for runoff prediction in the Three Gorges Area of china.

关键词： SCS-CN method direct runoff initial abstraction ratio rainfall-runoff events

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浑太河污染物入河控制量研究

水电能源科学 2010年第12期28卷 21-25页

作者：付意成魏传江臧文斌李其峰孙秀芬刘和平中国水利水电科学研究院水资源所北京100038 清华大学北京100084 广西北部湾投资集团有限公司广西南宁530028

结合浑太河水资源网络节点图,针对计算单元部门供水预测数据,计算了点源、非点源污染物入河量,并预测了浑太河污染物入河量。以水功能区水体纳污能力为依据,给出基于规划水平年的变动污染物入河控制量。计算结果证实了该方法可行、有效。

关键词：网络节点图水功能区点源非点源入河控制量

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基于UML的诊断推理策略研究

计算机工程与应用 2003年第9期39卷 55-57页

作者：郭永洪傅泽田田东中国农业大学经济管理学院

该文根据鱼病专家的诊断知识,提出了将专家知识分为规划层—策略层—事实层三层的层次结构,采用UML对其进行建模,为实现元推理提供了一种机制,从而实现了将规划知识与知识库分离,提高了诊断的质量与效率。

关键词：推理策略 UML 诊断

柴达木盆地东部第四纪水文地质条件与生物气成藏

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石油与天然气地质 2003年第4期24卷 341-345页

作者：王明明李本亮魏国齐李景明中国地质大学北京100083 中国石油勘探开发研究院廊坊分院河北廊坊065007

柴达木盆地东部昆仑山脉的那仁格勒河水系在乌图美仁 -台南东 -涩北 -驼峰山地区上新统 -更新统形成了那 -驼地下水循环系统 ,其两侧的达布逊湖洼陷和一里坪洼陷区属汇水盆地性质的停滞水文地质特征。台南构造以南的那 -驼地下水循环系... 详细信息

柴达木盆地东部昆仑山脉的那仁格勒河水系在乌图美仁 -台南东 -涩北 -驼峰山地区上新统 -更新统形成了那 -驼地下水循环系统 ,其两侧的达布逊湖洼陷和一里坪洼陷区属汇水盆地性质的停滞水文地质特征。台南构造以南的那 -驼地下水循环系统控制区 ,地层水显著咸化期在 3× 10 4a左右的晚更新世晚期。该期地层水溶解气量基本达到饱和。其生物气成藏机制有两种 :(1)地层水显著咸化期溶解气析出、运移、聚集成藏 ;(2.)那 -驼地下水循环系统携带南部较淡水区溶解的生物气向北部咸水区运移、析出、聚集成藏。根据水文地质特征及含油气系统特征确定船形丘构造东侧 -鸭南 -台南 -涩北为第四系生物气最有利富集区 ,其南北两侧及驼峰山 -盐湖、别勒湖南斜坡为较有利区带 ;船形丘 -鸭南 -南陵丘 -盐湖构造带为第三系生物气有利富集区带。

关键词：生物气成藏水文地质条件气藏勘探柴达木盆地东部地区第四纪地质特征

Management Strategies and research Orientations of Forest Diseases and Pests in china

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Chinese Forestry Science and Technology 2002年第2期1卷 64-69页

作者： ZHANG Xingyao LIANG Jun LU Quan YAN Donghui LUO Youqing XU Zhichun WEN Junbao1. research Institute of Forest Ecology. Environment and Protection. Chinese Academy of Forestry. beijing, 100091. P R {2.:2. College of Biological Sciences and Technology. Beiiine Forestry university. Beiiine. 100083. P R {2.

Forest diseases and pests are perceived as a growing hazard to china economy. It is a common conclusion that the actualities of forest pests in china are no effective measures to the old important pests, some secondary pests are ascending to chief pests, increasing devastation from exotic pests, frequent ecological pest eruption induced by environmental detriment and host-leading diseases to threaten the "Western Development Project "in china, which is the most important economical strategy to china; th...

关键词： Management Strategy Forest Disease Forest Pest china

Constructing the Metabolic and regulatory Pathways in Germinating Rice Seeds through Proteomic Approach

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Constructing the Metabolic and regulatory Pathways in Germin...