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一种免疫克隆选择算法在BP网络学习中的应用

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计算机工程 2007年第5期33卷 164-165,167页

作者：姜新农王文香中国科技大学计算机科学技术系合肥230027

在分析BP网络学习存在的问题后,采用了一种免疫克隆选择算法对BP网络的权值进行优化学习,并提出了一种新的变异方法,该变异方法可以根据亲和力的大小自适应调整抗体变异的幅度,与传统的高斯变异相比,不但简化了抗体的编码,还很好地体现... 详细信息

在分析BP网络学习存在的问题后,采用了一种免疫克隆选择算法对BP网络的权值进行优化学习,并提出了一种新的变异方法,该变异方法可以根据亲和力的大小自适应调整抗体变异的幅度,与传统的高斯变异相比,不但简化了抗体的编码,还很好地体现了克隆选择算法抗体变异的特点,提高了算法的搜索能力和收敛性能。仿真实验表明,基于这种变异方法的免疫克隆选择算法可以很好地提高BP网络的学习速度,有效地避免算法过早收敛的问题。

关键词： BP网络免疫克隆选择算法变异运动学逆问题

Design and implementation of an optical simulation environment for bioluminescent tomography studies

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Progress in Natural Science:Materials International 2007年第1期17卷 87-94页

作者： LI Hui, TIAN Jie, LUO Jie, LU Yujie, CONG wenxiang and wang Ge ( Department of Education Technology, Capital Normal University, Beijing 100037, China Key Laboratory of Complex Systems and Intelligence Science, Institute of Automation, Chinese Academy of Sciences, Beijing 100080, China Bioluminescent Tomography Laboratory, Department of Radiology & Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa 52242, USA) Department of Education Technology Capital Normal University Beijing 100037 China Key Laboratory of Complex Systems and Intelligence Science Institute of Automation Chinese Academy of Sciences Beijing 100080 China Bioluminescent Tomography Laboratory Department of Radiology & Department of Biomedical Engineering University of Iowa Iowa City Iowa 52242 USA

As a challenging task for bioluminescent tomography simulation, a virtual optical environment is needed to solve the forward problem accurately, that is, to achieve a high precision for bioluminescent signal synthesis on the external body surface of a small animal. The molecular optical simulation environment named MOSE is implemented using the C++ programming language and the OpenGL techniques, including a user-friendly interface with interactive tools facilitating users' operations. The accuracy of the virtual optical environment is verified by error analysis of mesh simplification and comparison between MOSE results and experimental data. This virtual optical environment is accurate, flexible and efficient to simulate the photon propagation in complicated tissues, which has a great potential to become a software platform for bioluminescent tomography studies and other molecular imaging applications.

关键词： molecular imaging biolumlnescent tomography photon propagation Monte Carlo method.

FLNG液化冷剂压缩机和主制冷换热器关键技术的突破

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天然气工业 2016年第1期36卷 129-136页

作者：吴尧增王文祥洪毅柯尔钦乎中海油研究总院

为解决海上天然气长距离管输的问题(成本高和流动安全保障等),FLNG(floating liquefied natural gas)浮式液化天然气开发技术应运而生。目前,受国内相关行业发展水平的制约,FLNG液化核心设备均需进口,设备价格高、项目投资大。为此,基... 详细信息

为解决海上天然气长距离管输的问题(成本高和流动安全保障等),FLNG(floating liquefied natural gas)浮式液化天然气开发技术应运而生。目前,受国内相关行业发展水平的制约,FLNG液化核心设备均需进口,设备价格高、项目投资大。为此,基于目前FLNG主要的液化工艺,分析了国内外液化核心设备(冷剂压缩机、大型压缩机驱动器和大型液化换热器)的运用现状和关键技术——①开停车、火灾及变工况下的稳定运行技术;②FLNG晃荡工况对换热器性能和安全的影响;③采用改进后的制造技术和制造工艺,满足FLNG运用的需求;④外部管道及接口补偿技术;⑤泄露监测技术,针对性地归纳了其实现国产化的技术需求和发展方向,提出了开发设想和建议:FLNG主要液化核心设备国产化要充分依托国内企业,在设计技术、材料、制造技术上充分借鉴国外技术发展思路,加大企业与项目的联系程度,充分整合资源突破关键技术,加大试验平台建设和试验验证,实现样机突破和中试运用,为最终的工程运用和降低项目投资打下基础。

关键词： FLNG 液化核心设备技术及运用现状关键技术国产化冷剂压缩机大型压缩机驱动器大型液化换热器

Functional characterization of pod shattering related genes in Brassica napus

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Functional characterization of pod shattering related genes ...

2018全国植物生物学大会

作者： Hongtao Cheng Jia Liu Mengyu Hao Bingli Ding wenxiang wang Rijin Zhou Wen Chu Hui wang Qiong Hu Oil Crops Research Institute Key Laboratory for Biological Sciences and Genetic Improvement of Oil CropsChinese Academy of Agricultural Sciences

Majority of rapeseed cultivars shatter seeds upon maturity especially under hot-dry and windy conditions,reducing yield and gross margin return to *** the genetic mapping result,one main effect QTL(qSRI.A9.2 R2=38%) of pod shatter near isogenic lines was constructed by backcrossing and molecular marker assisted selection *** QTL has been mapped into about 180 kb region and one candidate gene was selected to perform the genetic ***,pod shattering related genes,including FUL,ALC,IND,and SHIP,were also mutated by CRISPR/*** mutation of allhomoeologs of these genes influenced differentiation of the separation layer inthe valve margin,thereby results in change of the pod shattering *** markers developed in our study may provide a cost-effective and an efficient method for introgression and pyramiding of favorable alleles for pod shatter *** the pod shattering related genes studies may allow us to improvepod shattering in oilseed crops.

关键词： Pod shattering GWAS MAS CRISPR/Cas9

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一种硅芯片外引线键合的热压焊简易装置

中国机械工程 2005年第Z1期16卷 417-419页

作者：王权丁建宁王文襄江苏大学镇江212013 江苏大学镇江212013 昆山双桥传感器测试技术有限公司苏州215325

为满足压阻式压力传感器封装工艺中硅芯片外引线键合的要求,研制了热压焊简易装置;研究了金铝压焊处金属间化合物扩散深度随温度增长关系.键合试验中,调节压焊控制台电压使衬底温度保持在150～200℃,压焊头辟刀温度保持在150℃左右,保... 详细信息

为满足压阻式压力传感器封装工艺中硅芯片外引线键合的要求,研制了热压焊简易装置;研究了金铝压焊处金属间化合物扩散深度随温度增长关系.键合试验中,调节压焊控制台电压使衬底温度保持在150～200℃,压焊头辟刀温度保持在150℃左右,保证了压焊点接触的可靠性.实践表明,该装置容易操作,适合于大批量生产,具有一定的经济效益.

关键词：压阻式压力传感器引线键合热压焊金丝

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基于拣货员协同合作的订单拣选策略研究

工业工程 2021年第3期24卷 54-59页

作者：钱吴永王文香江南大学商学院江苏无锡214122

本文对单区块人工作业系统中多个拣货员在拣货作业过程中发生的拣选堵塞问题展开研究。构建基于协同合作的拣选路径模型,通过交换拣选订单,动态调整拣选路径,减少拣选堵塞的产生。案例分析结果表明,与S型策略相比,协同合作策略在减少拣... 详细信息

本文对单区块人工作业系统中多个拣货员在拣货作业过程中发生的拣选堵塞问题展开研究。构建基于协同合作的拣选路径模型,通过交换拣选订单,动态调整拣选路径,减少拣选堵塞的产生。案例分析结果表明,与S型策略相比,协同合作策略在减少拣选堵塞、缩短订单服务时间方面具有明显的优越性。最后,从影响拣选作业效率的可控因素角度进行敏感性分析,了解不同情况下协同合作策略对拣选作业效率优化的具体表现。

关键词：人工作业系统拣选堵塞 S型策略协同合作策略

Comparative analysis Nsa cytoplasmic male sterility (CMS) and its maintainer mitochondrial genome to reveal the CMS-associated gene

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Comparative analysis Nsa cytoplasmic male sterility (CMS) an...

2018中国作物学会学术年会

作者：桑世飞 Hongtao CHENG Jia Liu wenxiang wang Li Fu Desheng MEI Qiong Hu Oil Crops Research Institute of CAAS Key Laboratory of Biology and Genetic Improvement of Oil CropsMinistry of Agriculture Graduate School of Chinese Academy of Agricultural Sciences Huazhong Agriculture University

Cytoplasmic male sterility(CMS) is a widely spread phenomenon that plant inability to produce nonfunctional pollen among higher plants and has been extensively studied in serial analysis of cytology and molecular *** Cytoplasmic male sterility is a novel Brassica napus.L alloplasmic male sterility system derived from somatic *** the development of the sequencing techonology,comparative analyses of complete mitochondrial genomes of CMS lines with and iso-nuclear maintainer line in several CMS systems were helpful for identified CMS-associated *** this study,we employed Roche/454 pyro-sequencing technology to align analysis of the organelle genome,and screen Nsa CMS-associated gene and uncover the source of alloplasmic in Nsa CMS *** and SMART online server were employed to identify9 open read frames(ORFs) with chimeric structure,in which three ORFs:or/224,or/309,or/346 chimeric with atp8,coxl,coxl,***,the three specific ORFs were most likely considered to be Nsa CMSassociated candidate *** 2 x CaMV 35 S and anther specific expression gene AP3 promoter were used to drive expression of these candidate genes in Brassica napus and Arabidopsis,*** candidate genes of transgenic plant were all observed abortion phenotype in *** only or/346 transgenic plants of Brassica napus observed abortion *** expression analysis showed that ORF346 obviously inhibited the growth of Escherichia *** results suggested that or/346 may be the candidate genes of Nsa CMS but the detailed function need further study to verify.

关键词： Cytoplasmic male sterility mitochondrial Brassica napus orf346

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高性能多媒体SoC分组访存调度算法

计算机辅助设计与图形学学报 2011年第9期23卷 1585-1592页

作者：张广飞汪文祥蒋毅飞苏孟豪中国科学院计算机系统结构重点实验室北京100190 中国科学院计算技术研究所北京100190 中国科学院研究生院北京100049 北京龙芯中科技术服务中心有限公司北京100190

根据多媒体处理单元的访存特点,提出一种面向高性能多媒体SoC的分组访存调度算法.该算法将访存请求按照访存ID和页地址分组,以访存组为单位进行乱序调度,并通过维护相同ID访存请求之间的顺序保证访存的正确性:综合考虑访存单元的访存效... 详细信息

根据多媒体处理单元的访存特点,提出一种面向高性能多媒体SoC的分组访存调度算法.该算法将访存请求按照访存ID和页地址分组,以访存组为单位进行乱序调度,并通过维护相同ID访存请求之间的顺序保证访存的正确性:综合考虑访存单元的访存效率和服务质量要求,在每个访存单元独立的调度周期内提供最低带宽保障服务.将该分组访存调度算法应用于访存调度装置,实际应用仿真结果表明,与已有基于带宽分配的访存调度算法相比,文中算法在保障访存单元带宽需求的同时降低了访存延迟,并将平均带宽利用率提高了15%.

关键词：访存调度多媒体片上系统 SDRAM

Screen Exposure and Behavior Problems among Preschoolers:A Meta-Analysis

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Frontiers of Education in China 2024年第1期19卷 99-117页

作者： LU wenxiang LI Xiaowei Faculty of Education Beijing Normal UniversityBeijing 100875China

Conflicting results have existed in research on the relationship between screen exposure and behavior problems among preschoolers,so it is necessary to clarify the relationship and provide guidelines regulating their screen *** searching and screening of literature,48 independent samples from 43 quantitative studies are included in the meta-analysis,with 76,049 *** results show a weak positive correlation between screen exposure and behavior problems among preschoolers(r=0.169).The findings show that preschoolers’age and length of exposure have a significantly moderate effect on the relationship between screen exposure and behavior problems among preschoolers,while media types and study design do ***,a stronger correlation is observed between excessive screen exposure and behavior problems among preschoolers aged *** for the appropriate use of digital media among preschoolers and media education are also presented.

关键词： screen exposure media usage preschoolers behavior problems meta-analysis