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Multiple-Constraint-Aware RWA Algorithms Based on a Comprehensive Evaluation Model:Use in Wavelength-Switched Optical Networks

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ZTE Communications 2012年第3期10卷 55-61页

作者： Hui Yang YongliZhao Shanguo Huang dajiang wang Xuping Cao Xuefeng Lin State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Beijing 100876 China ZTE Corporation Shenzhen 518057 China

Because of explosive growth in Internet traffic and high complexity of heterogeneous networks, improving the routing and wavelength assignment （RWA） algorithm in underlying optical networks has become very important. Where there are multiple links between different the node pairs, a traditional wavelength-assignment algorithm may be invalid for a wavelength-switched optical networks （WSON） that has directional blocking constraints. Also, impairments in network nodes and subsequent degradation of optical signals may cause modulation failure in the optical network. In this paper, we propose an RWA algorithm based on a novel evaluation model for a WSQN that has multiple constraints. The algorithm includes comprehensive evaluation model （CEM） and directional blocking constraint RWA based on CEM （DB-RWA）. Diverse constraints are abstracted into various constraint conditions in order to better assign routing and wavelength. We propose using the novel CEM to optimize routing according to an assessed value of constraints on transmission performance. This eliminates the effects of physical transmission impairments in a WSON. DB-RWA based on CEM abstracts directional blocking conditions in multiple links between network nodes into directional blocking constraints. It also satisfies rigorous network specifications and provides flexibility, scalability, and first-fit rate for the backbone, especially in multiple links between WSON nodes.

关键词： RWA WSON multiple links between nodes pair directionalblocking constraint comprehensive evaluation model

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Dramatic decline of observed atmospheric CO_(2) and CH_(4) during the COVID-19 lockdown over the Yangtze River Delta of China

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Journal of Environmental Sciences 2023年第2期124卷 712-722页

作者： Miao Liang Yong Zhang Qianli Ma dajiang Yu Xiaojian Chen Jason Blake Cohen Meteorological Observation Center China Meteorological AdministrationBeijing 100081China Lin’an Atmospheric Regional Background Station China Meteorological Administration(CMA)Hangzhou 311307China Longfengshan Regional Background Station China Meteorological Administration(CMA)Heilongjiang 150200China Shanxi Meteorological Information Center China Meteorological Administration(CMA)Shanxi 030000China School of Environment and Spatial Informatics China University of Mining and TechnologyXuzhou221116China

The temporal variation of greenhouse gas concentrations in China during the COVID-19 lockdown in China is analyzed in this work using high resolution measurements of near surface ΔCO_(2),ΔCH_(4) andΔCO concentrations above the background conditions at Lin’an station(LAN),a regional background station in the Yangtze River Delta region.During the pre-lockdown observational period(IOP-1),bothΔCO_(2) andΔCH_(4) exhibited a significant increasing trend relative to the 2011-2019 climatological mean.The reduction ofΔCO_(2),ΔCH_(4) andΔCO during the lockdown observational period(IOP-2)(which also coincided with the Chinese New Year Holiday)reached up to 15.0 ppm,14.2 ppb and 146.8 ppb,respectively,and a reduction ofΔCO_(2)/ΔCO probably due to a dramatic reduction from industrial emissions.ΔCO_(2),ΔCH_(4) and ΔCO were observed to keep declining during the post-lockdown easing phase(IOP-3),which is the synthetic result of lower than normal CO_(2) emissions from rural regions around LAN coupled with strong uptake of the terrestrial ecosystem.Interestingly,the trend reversed to gradual increase for all species during the later easing phase(IOP-4),with ΔCO_(2)/ΔCO constantly increasing from IOP-2 to IOP-3 and finally IOP-4,consistent with recovery in industrial emissions associated with the staged resumption of economic activity.On average,ΔCO_(2) declined sharply throughout the days during IOP-2 but increased gradually throughout the days during IOP-4.The findings showcase the significant role of emission reduction in accounting for the dramatic changes in measured atmosphericΔCO_(2) and ΔCH_(4) associated with the COVID-19 lockdown and recovery.

关键词： Atmospheric CO_(2) Atmospheric CH_(4) COVID-19 lockdown The Yangtze river delta

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Bio-inhibitive effect of an algal symbiotic bacterium on corrosion of magnesium in marine environment

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Journal of Magnesium and Alloys 2023年第12期11卷 4603-4618页

作者： Yuqiao Dong Guang-Ling Song Yuqing Xu dajiang Zheng College of Materials Xiamen UniversityXiamen 361005China Department of Ocean Science and Engineering Southern University of Science and TechnologyShenzhenChina State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen University422 S.Siming RdXiamen361005China The University of Queensland School of Mechanical and Mining EngineeringDivision of Materials EngineeringSt LuciaQld 4072 Australia Institute of Corrosion Science and Technology Guangzhou510530GuangdongChina

It is a longstanding and challenging task to develop sustainable environment-friendly and cost-effective corrosion-protection technologies for Mg alloys, especially under marine conditions in which corrosion can normally be significantly accelerated by bacterial activity. However,this paper reports on the corrosion of highly active Mg interestingly inhibited by an algal-symbiotic bacterium Bacillus altitudinis. The corrosion of Mg in the presence of the bacterium drastically reduced by one order of magnitude after 14 days of immersion. This means that the algal-symbiotic bacterium widely available in natural ocean environments may be employed as a green and sustainable inhibitor in the marine industry. Based on electrochemical measurements, surface analyses and microbe experiments, a combined inhibition mechanism is proposed in the paper to interpret the interesting corrosion behavior of Mg.

关键词： Magnesium Corrosion inhibition Marine environment Biofilm Bacterium

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Layered double hydroxide(LDH) for multi-functionalized corrosion protection of metals: A review

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Journal of Materials Science & Technology 2022年第7期102卷 232-263页

作者： Yanhui Cao dajiang Zheng Fan Zhang Jinshan Pan Changjian Lin State Key Laboratory of Physical Chemistry of Solid Surfaces Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research InstituteXiamen 361101China College of Materials Xiamen UniversityXiamen 361005China Division of Surface and Corrosion Science Department of ChemistryKTH Royal Institute of TechnologyStockholm SE-10044Sweden

Layered double hydroxide(LDH) has been widely developed in the field of corrosion and protection in recent years based on its unique characteristics including anion capacity, anion exchange ability, structure memory effect, and barrier resistance. This paper comprehensively reviews recent work on the preparations, properties of LDH in the forms of powder and film and their applications in different environments in corrosion and protection. Some novel perspectives are also proposed at the end of the review for future research in corrosion and protection field.

关键词： Layered double hydroxide Powder Films Corrosion protection

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金刚石基材料及其表面微通道制备技术在高效散热中的应用

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金刚石与磨料磨具工程 2024年第3期44卷 286-296页

作者：邓世博夏永琪吴明涛岳晓斌雷大江四川省精密超精密加工工程技术研究中心成都610200 南京航空航天大学机电工程学院南京210016 中国工程物理研究院材料研究所四川绵阳621908

随着第三代半导体材料的兴起,电子器件逐渐向着高功率、小型化、集成化方向发展。传统散热技术已难以满足第三代半导体器件高热流的散热要求,由此带来的温度堆积问题成为器件失效的主要原因。金刚石基材料具有优异的散热性能,基于此材... 详细信息

随着第三代半导体材料的兴起,电子器件逐渐向着高功率、小型化、集成化方向发展。传统散热技术已难以满足第三代半导体器件高热流的散热要求,由此带来的温度堆积问题成为器件失效的主要原因。金刚石基材料具有优异的散热性能,基于此材料的高效散热技术有望解决高热流散热难题。总结了金刚石基材料的发展及其表面微通道制备的主要方法,综述了金刚石基材料在高效散热领域中的应用和未来的发展方向。金刚石基材料高效散热技术的发展及应用能够为高热流密度散热难题的解决提供技术支撑。

关键词：金刚石微通道加工高效散热

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激光焊接7A52高强度铝合金焊缝气孔形成机理研究

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重庆交通大学学报（自然科学版） 2024年第3期43卷 128-134页

作者：苏菠陈大江张大斌胡江张淑清简汉青广西警察学院交通管理工程学院广西南宁530028 贵州大学机械工程学院贵州贵阳550025

为实现航空航天装备和汽车的结构轻量化,故使用厚度连续变化的7A52高强度铝合金板代替传统不锈钢等金属,从结构和材料密度两个角度实现轻量化。通过恒定功率的激光焊接铝合金变厚板时,单位体积内吸收的热量不同,匙孔演变产生气孔,影响... 详细信息

为实现航空航天装备和汽车的结构轻量化,故使用厚度连续变化的7A52高强度铝合金板代替传统不锈钢等金属,从结构和材料密度两个角度实现轻量化。通过恒定功率的激光焊接铝合金变厚板时,单位体积内吸收的热量不同,匙孔演变产生气孔,影响焊缝质量。焊缝内气孔主要由金属蒸气作用到匙孔壁,匙孔壁受力不均产生,为探究匙孔动态演变产生气孔的机理,提出将匙孔壁面的局部范围空间分为一定数量的小正方体块,计算相对较小范围内的能量和力,计算结果结合焊缝微观检测结果,分析力对匙孔壁面的作用。厚度小的一端焊缝充分熔透,匙孔壁面受到金属蒸气产生的压力和表面张力的不平衡作用,匙孔壁面局部范围形成气泡,厚度大的一端未熔透。铝合金焊缝凝固后,晶粒生长影响气泡的逃逸路径,气泡最后演变为气孔。

关键词：机电工程激光焊接焊缝铝合金匙孔

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A Green Conversion Coating on a Magnesium Alloy for Corrosion Protection

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Acta Metallurgica Sinica(English Letters) 2023年第10期36卷 1630-1648页

作者： Tong Bu Ruijie Jia Tao Ying Andrej Atrens Pengbo Chen dajiang Zheng Fuyong Cao Center for Marine Materials Corrosion and Protection College of MaterialsFujian Key Laboratory of Surface and Interface Engineering for High Performance MaterialsXiamen UniversityXiamen361005China National Engineering Research Center of Light Alloy Net Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China School of Mechanical and Mining Engineering Centre for Advanced Materials Processing and Manufacturing(AMPAM)The University of QueenslandSt.LuciaBrisbaneQLD4072Australia First Affiliated Hospital of Xi’an Jiao Tong University Xi’an710061China

A novel coating on the Mg1Mn alloy was produced by anodic polarization combined with hydrothermal treatment(AP+H)in 0.1 M Na2CO3 solution.The microstructure and protection of the coating were evaluated.The coating consisted of MgCO3,Mg(OH)2 and MgO,and provided satisfactory protection in 3.5 wt%NaCl with a corrosion rate of 0.07 mm y−1 in 72 h.However,after that period,the corrosion rate of the specimen increased due to the damage of the coating.The failure of the coating was strongly related to the second phase particles(e.g.Zr particles)or impurities in the matrix.The AP+H coating is supposed to be used as a primer coating for Mg applications in kitchen ware,biomedical areas or industry.

关键词： Coating Magnesium alloy Hydrothermal Corrosion resistance

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Weld Defects in Laser-Welded 7A52 High-Strength Aluminum Alloy Plates with Varying Thicknesses

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Journal of Beijing Institute of Technology 2023年第4期32卷 406-421页

作者： dajiang Chen Dabin Zhang Bo Su Zhijian Lai Jijiao Yin An Zhang School of Traffic Management Engineering Guangxi Police CollegeNanning 530028China School of Mechanical Engineering Guizhou UniversityGuiyang 550025 China

This study aims to explore a method suitable for welding 7A52 high-strength aluminum alloy plates with continuously varying thicknesses and the causes of microscopic defects in welds in order to improve welding quality.Comparative tests were conducted to analyze weld defects and deformation when welding the aluminum alloy plates with varying thicknesses at constant laser power.The laser power required for melting welds at varying-thickness positions was estimated.Weld defects and deformation when welding aluminum alloy plates with varying thicknesses at con-tinuous variable laser power were detected.The causes of microscopic weld defects during constant-power welding were analyzed.The welding defects and deformation and the welding quality were improved by welding aluminum alloy plates at continuous variable power.

关键词： aluminum alloy continuous variable laser power micro-defects deformations

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苹果响应盐胁迫相关miRNA的深度测序数据集

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农业大数据学报 2024年第1期6卷 14-23页

作者：刘昭高源王昆孙思邈代瑛姿路翔田雯王大江冯建荣石河子大学农学院/特色果树栽培生理与种质资源利用兵团重点实验室新疆石河子832000 中国农业科学院果树研究所/农业农村部园艺作物种质资源利用重点实验室辽宁兴城125100

土壤盐渍化已成为限制农作物产量与质量的重要因素之一,影响着全世界范围内的农作物产量。苹果作为一种重要的水果作物,盐胁迫的危害及耐盐砧木的缺乏已成为威胁现代苹果产业健康可持续发展的重要问题。因此,研究苹果对盐胁迫的反应和... 详细信息

土壤盐渍化已成为限制农作物产量与质量的重要因素之一,影响着全世界范围内的农作物产量。苹果作为一种重要的水果作物,盐胁迫的危害及耐盐砧木的缺乏已成为威胁现代苹果产业健康可持续发展的重要问题。因此,研究苹果对盐胁迫的反应和适应具有重要的现实意义和紧迫性。本研究分别以0%、0.2%和0.6%NaCl处理0、4、8和12天后的珠美海棠实生苗为试验材料,从叶片及根系中提取总RNA,构建RNA-seq文库,共鉴定获得575个miRNA,包括315个已知mdm-miRNA和260个新miRNA。此外,Differential Expression(DE) miRNA对盐胁迫反应具有组织特异性表达模式。同时提供珠美海棠miRNA深度测序的数据集,结合生物信息学方法对原始数据质量控制,获得高质量序列并利用BLAST软件将预测靶基因序列与NR、Swiss-Prot、Pfam等数据库比对,获得响应盐胁迫相关基因的注释信息。GO分析表明与盐胁迫有关miRNA及靶基因主要参与生物过程中对刺激的反应。本研究为珠美海棠的利用提供理论数据基础,并为耐盐砧木的选育提供有力支持。

关键词：苹果盐胁迫 miRNA 深度测序生物信息学

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Active,compact,wideband,receiving filtenna with power adaptation for space-limited wireless platforms

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Chinese Journal of Aeronautics 2022年第8期35卷 7-11页

作者： LI Daotong YU Yaqing TANG Ming-Chun LI dajiang MU Dongmei LI Mei School of Microelectronics and Communication Engineering Chongqing UniversityChongqing 400044China Institute of Wireless Mobile Information Technology School of Electronic Engineering of Beijing UniversityPosts and TelecommunicationsBeijing 100876China

An active,compact,wideband,receiving filtenna with power adaptation for space-limited wireless platforms is presented.By organically combining a filtering antenna and a Variable Gain Amplifier(VGA),the proposed co-designed active filtenna is achieved.Its power adaptation is empowered by controlling gain of the VGA unit.A demonstrated prototype with a compact overall size is fabricated,assembled and measured.Good performances are achieved.Furthermore,in any condition,the proposed active filtenna displays outstanding impedance matching(|S_(11)|<−10 dB)and high passband skirt selectivity at upper and lower stopbands(Selectivity≥170 dB/GHz).

关键词： Amplifier Compact Power adaptation VGA Wideband

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