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Novel electromagnetism-like mechanism method for multiobjective optimization problems

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Journal of Systems Engineering and Electronics 2015年第1期26卷 182-189页

作者： lixia han Shujuan Jiang Shaojiang Lan School of Computer Science and Technology China University of Mining and Technology

As a new-style stochastic algorithm, the electromagnetism-like mechanism（EM） method gains more and more attention from many researchers in recent years. A novel model based on EM（NMEM） for multiobjective optimization problems is proposed, which regards the charge of all particles as the constraints in the current population and the measure of the uniformity of non-dominated solutions as the objective function. The charge of the particle is evaluated based on the dominated concept, and its magnitude determines the direction of a force between two particles. Numerical studies are carried out on six complex test functions and the experimental results demonstrate that the proposed NMEM algorithm is a very robust method for solving the multiobjective optimization problems.

关键词： electromagnetism-like mechanism(EM) method multi-objective optimization problem particle Pareto optimal solutions

Co-optimization strategy between array operation and weight mapping for flash computing arrays to achieve high computing efficiency and accuracy

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Science China(Information Sciences) 2023年第2期66卷 289-290页

作者： Guihai YU Peng HUANG Runze han lixia han Xiaoyan LIU Jinfeng KANG Institute of Microelectronics Peking University

Dear editor,Flash memory is a promising candidate to realize in-memory computing due to its mature fabrication technology [1]. Various efforts to implement neural networks using flash computing arrays have been reported [2, 3]. To realize higher computing efficiency, it is an effective method to activate more word lines(WL) at the same time for flash computing arrays [4]. When increasing the activated WL,

关键词： Mapping

Fabricating UCNPs-AuNPs Fluorescent Probe for Sensitive Sensing Thiamphenicol

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Chemical Research in Chinese Universities 2022年第6期38卷 1453-1460页

作者： YI Jiaqi LI Xiaoshuang CUI Di han lixia JIANG Wei ZhanG Renguo NIU Na CHEN Ligang Key Laboratory of Forest Plant Ecology College of ChemistryChemical Engineering and Resource UtilizationNortheast Forestry UniversityHarbin150040P.R.China

A novel fluorescent probe has been constructed based on fluorescence resonance energy transfer(FRET)between upconversion nanomaterials(UCNPs)NaYF4:Yb,Er and gold nanoparticles(AuNPs).The fluorescent“off-on”switching was formed for the detection of thiamphenicol(TAP)in egg *** fluorescence of UCNPs can be quenched to a certain degree by *** adding TAP,the AuNPs generated aggregation and the fluorescence of UCNPs was *** synthesized amination UCNPs and AuNPs were characterized by Fourier transform infrared spectroscopy(FTIR),UV-Vis,X-ray diffraction(XRD),energy dispersive spectrometer(EDS),and transmission electron microscope(TEM)techniques for observation and *** a model target,the detection of TAP has two linear ranges in the buffer solution within 0.01–0.1µmol/L and 0.1–1µmol/L using this fluorescent *** detection limit was obtained to be 0.003µmol/L(S/N=3),which is favorable for trace *** recovery of TAP from 98.2%to 105.3%was obtained,and the relative standard deviation(RSD)was from 2.5%to 4.3%.Furthermore,the method established in this study based on the UCNPs auto-low background fluorescence has high selectivity and strong ability to eliminate interference,which is beneficial to analyzing complex samples.

关键词： Upconversion nanomaterial Fluorescent switch Thiam-phenicol Fluorescence resonance energy transfer Egg analysis

Characterization of a new smog chamber for evaluating SAPRC gas-phase chemical mechanism

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Journal of Environmental Sciences 2020年第9期32卷 14-22页

作者： Kangwei Li Chao Lin Chunmei Geng Stephen White Linghong Chen Zhier Bao Xin Zhang Yanyun Zhao lixia han Wen Yang Merched Azzi State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China CSIRO Energy North RydeNSW 1670Australia New South Wales Department of Planning Industry and EnvironmentLidcombeNSW 1825Australia

A new state-of-the-art indoor smog chamber facility(CAPS-ZJU) has been constructed and characterized at Zhejiang University,which is designed for chemical mechanism evaluation under well-controlled conditions.A series of characterization experiments were performed to validate the well-established experimental protocols,including temperature variation pattern,light spectrum and equivalent intensity(JNO2),injection and mixing performance,as well as gases and particle wall *** addition,based on some characterization experiments,the auxiliary wall mechanism has been setup and *** chamber experiments were performed across a broad range of experimental scenarios,and we demonstrated the ability to utilize these chamber data for evaluating SAPRC chemical *** was found that the SAPRC-11 can well predict the 03 formation and NO oxidation for almost all propene runs,with 6 hr △(O3-NO) model error of-3%±7%,while the final O3 was underestimated by-20% for isoprene *** for toluene and p-xylene experiments,it was confirmed that SAPRC-11 has significant improvement on aromatic chemistry than earlier version of SAPRC-07,although the aromatic decay rate was still underestimated to some *** model sensitivity test has been carried out,and the most sensitive parameters identified are the initial concentrations of reactants and the light intensity as well as HONO offgasing rate and 03 wall loss *** of which demonstrated that CAPS-ZJU smog chamber could derive high quality experimental data,and could provide insights on chamber studies and chemical mechanism development.

关键词： mechanism chemical CAPS

干旱胁迫对美国流苏树幼苗光合特性和叶片结构的影响

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植物资源与环境学报 2023年第3期32卷 61-70页

作者：韩睿婷韩丽霞张鸽香南京林业大学风景园林学院江苏南京210037

以美国流苏树(Chionanthus virginicus Linn.)2年生幼苗为实验材料,设置对照(土壤相对含水量为75%~80%)、轻度干旱胁迫(土壤相对含水量为55%~60%)、中度干旱胁迫(土壤相对含水量为40%~45%)和重度干旱胁迫(土壤相对含水量为25%~30%)4个... 详细信息

以美国流苏树(Chionanthus virginicus Linn.)2年生幼苗为实验材料,设置对照(土壤相对含水量为75%~80%)、轻度干旱胁迫(土壤相对含水量为55%~60%)、中度干旱胁迫(土壤相对含水量为40%~45%)和重度干旱胁迫(土壤相对含水量为25%~30%)4个处理水平,对不同干旱胁迫条件下美国流苏树叶片光合特性和结构的变化进行了比较和分析。结果显示:随胁迫时间延长,各处理组美国流苏树叶片的叶绿素a、叶绿素b和总叶绿素含量呈波动降低的趋势。在胁迫14~42 d,美国流苏树叶片的叶绿素a、叶绿素b和总叶绿素含量在各处理组间均无显著差异;在胁迫70 d,中度和重度干旱胁迫处理组的上述3个指标均显著低于对照组。总体上看,随胁迫程度增加,同一时间美国流苏树叶片净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)呈降低的趋势;水分利用效率(WUE)呈波动降低的趋势;胁迫14、28和56 d的叶片胞间CO_(2)浓度(Ci)呈降低的趋势,胁迫42和70 d的叶片Ci值呈波动升高的趋势,重度干旱胁迫70 d的叶片Ci值最大。各干旱胁迫处理组叶片最大荧光(F_(m))和可变荧光(F_(v))低于对照组,但均无显著差异;初始荧光(F_(o))高于对照组,PSⅡ最大光化学效率(F_(v)/F_(m))和PSⅡ潜在活性(F_(v)/F_(o))低于对照组,但仅重度干旱胁迫处理组与对照组有显著差异。干旱胁迫处理后,美国流苏树叶片总厚度、栅栏组织厚度、海绵组织厚度和组织结构疏松度均增加,叶片组织结构紧密度和栅海比减小;中度和重度干旱胁迫下细胞中叶绿体和淀粉粒降解,嗜锇颗粒增多,质壁产生分离,细胞结构破坏严重。综上所述,美国流苏树在干旱胁迫下可以通过降低光合作用、改变叶片结构特征来提高抗旱能力,且在轻度干旱时具有较强的适应能力。

关键词：干旱胁迫美国流苏树光合特性解剖结构超微结构

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复杂地质条件下浅埋暗挖暗涵施工技术

水利水电技术 2011年第5期42卷 88-90页

作者：韩丽霞孙波中国人民武装警察部队水电第一总队广西南宁530028

1工程概述南水北调中线京石段应急供水工程（北京段）西四环暗涵上接卢沟桥暗渠，下接团城湖明渠，为总干渠的最后控制性工程，全长12．64km。本工程主要由Фm的双洞组成，共有建筑物座18座，

关键词：浅埋暗挖注浆支护喷射混凝土暗涵南水北调中线京石段应急工程

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外来物种入侵与本土物种分布区扩张的异同

生物多样性 2024年第1期32卷 130-145页

作者：韩丽霞王永健刘宣中国科学院动物研究所动物生态与保护生物学院重点实验室北京100101 华中农业大学园艺林学学院武汉430070 中国科学院大学北京100049

当今全球变化背景下,物种分布区正发生着快速变化,一类是人类活动介导下的生物入侵过程,另一类是本土物种的自然分布区扩张。两者之间既具有相似之处,亦有明显差异。探讨两者间异同是发展外来入侵物种管控和本土物种保护策略的基础科学... 详细信息

当今全球变化背景下,物种分布区正发生着快速变化,一类是人类活动介导下的生物入侵过程,另一类是本土物种的自然分布区扩张。两者之间既具有相似之处,亦有明显差异。探讨两者间异同是发展外来入侵物种管控和本土物种保护策略的基础科学问题。本文以两栖爬行类、鸟类和哺乳类等陆栖脊椎动物为例,在阐述外来物种入侵过程的基础上,将其与本土物种的分布区变化进行比较并阐述了两者间的异同。我们发现,伴随经济贸易发展和人口流动,外来物种正在加剧入侵;同时,发生分布范围变化的本土物种数量也在迅速增加。两者在分布区变化过程中的驱动因子、时空尺度、发生速度、物种特征的预测能力以及对新分布区的影响方面具有明显差异:人类活动介导下的外来物种入侵通常会经历长距离迁移,甚至跨越生物地理区系,并在入侵区快速扩散,物种特征在预测外来物种入侵过程中起着重要作用,对当地生物多样性造成严重威胁;本土物种分布区扩张通常发生在原生范围的邻近区域,发生速度较慢,物种特征在预测分布区扩展中的作用有限,且对新区域的负面影响较小。由于在短期内很难全面判定外来物种和发生分布区变化的本土物种的生态影响,我们建议应对新分布区内的外来物种和本土物种进行密切监测和长期研究,对其可能引发的生态学效应进行早期预警和评估,以最大限度地限制其潜在危害并保护生物多样性。

关键词：生物入侵生物多样性保护全球变化生态位动态分布区扩张

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河北大学出版社县域乡土教材的开发与维护

现代出版 2019年第4期 70-71页

作者：杨显硕付佳韩立霞河北大学出版社有限责任公司社科文化分社河北大学新闻传播学院

河北大学出版社成功开发了几套县域乡土教材。县域乡土教材的开发需要确立目标县域、编写者、编写方向与原则,注重编辑加工和后期维护,解决教材质量不高、发行不稳定、多媒体服务等问题。

关键词：河北大学出版社县域乡土教材开发维护

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江汉矿区水淹层挖潜实践及认识

江汉石油职工大学学报 2019年第5期32卷 23-25,35页

作者：韩利霞中石化江汉油田分公司江汉采油厂

基于水淹层不是无油而是含油饱和度下降这一认识,江汉采油厂对江汉矿区水淹层进行了一系列的挖潜实践。实践发现,水淹层含油饱和度与电阻绝对值关联性较小,与水淹层和围岩深侧向电阻差值关联性较大,且差值越小,含水率越低,反之则越高;... 详细信息

基于水淹层不是无油而是含油饱和度下降这一认识,江汉采油厂对江汉矿区水淹层进行了一系列的挖潜实践。实践发现,水淹层含油饱和度与电阻绝对值关联性较小,与水淹层和围岩深侧向电阻差值关联性较大,且差值越小,含水率越低,反之则越高;实践认为,低水淹区产建开发应聚焦在平面非均质形成的低水淹剩余油滞留区、层内非均质形成的低水淹剩余油滞留区、水驱压力平衡区和地下流场变化形成的剩余油再富集区等四类区域。

关键词：江汉矿区水淹层剩余油围岩电阻