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Prediction of ultimate tensile strength of Al-Si alloys based on multimodal fusion learning

Materials Genome Engineering Advances 2024年第1期2卷 104-119页

作者： longfei zhu Qun Luo Qiaochuan Chen Yu Zhang Lijun Zhang Bin Hu Yuexing Han Qian Li State Key Laboratory of Advanced Special Steels&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghaiChina School of Computer Engineering and Science Shanghai UniversityShanghaiChina College of Materials Science and Engineering Chongqing UniversityChongqingChina State Key Laboratory of Powder Metallurgy Central South UniversityChangshaChina CSMET Group Co. Ltd.ShanghaiChina Zhejiang Laboratory HangzhouChina National Engineering Research Center for Magnesium Alloy Chongqing UniversityChongqingChina National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqingChina

Exploring the“composition-microstructure-property”relationship is a long-standing theme in materials ***,complex interactions make this area of research *** on the image processing and machine learning techniques,this paper proposes a multimodal fusion learning framework that comprehensively considers both composition and microstructure in prediction of the ultimate tensile strength(UTS)of Al-Si ***,the composition and image information are collected from the literature and supplementary experi-ments,followed by the image segmentation and quantitative analysis of eutectic Si ***,the quantitative analysis results are combined with other features for three-step feature screening,and 12 key features are ***,four machine-learning models(i.e.,decision tree,random forest,adaptive boosting,and extreme gradient boosting[XGBoost])are used to predict the UTS of Al-Si *** results show that the quantitative analysis method proposed in this paper is superior to Image-Pro Plus(IPP)software in some *** XGBoost model has the best prediction performance with R^(2)=***,five mixed features and their critical values that significantly affect UTS are *** study provides enlightenment for the prediction of UTS of Al-Si alloys from composition and microstructure,and would be applicable to other alloys.

关键词： Al-Si alloys image processing machine learning multimodal property prediction

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基于自抗扰的永磁同步电机附加谐波损耗抑制方法

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电机与控制学报 2024年第2期28卷 87-98页

作者：韩雪岩刘文彬朱龙飞沈阳工业大学国家稀土永磁电机工程技术研究中心辽宁沈阳110870

针对永磁同步电机在变频器供电时,由时间电流谐波所引起的附加谐波损耗过大及难以在电机初始设计时被考虑到的问题,采用场路耦合联合仿真模型来计算电机的附加谐波损耗,并以4台现有的表贴式永磁同步电机为例,通过实验验证了场路耦合联... 详细信息

针对永磁同步电机在变频器供电时,由时间电流谐波所引起的附加谐波损耗过大及难以在电机初始设计时被考虑到的问题,采用场路耦合联合仿真模型来计算电机的附加谐波损耗,并以4台现有的表贴式永磁同步电机为例,通过实验验证了场路耦合联合仿真模型的有效性,为电机设计之初附加谐波损耗的选取,以及后续温升的计算提供了前期计算的方法。同时提出一种基于自抗扰技术的附加谐波损耗抑制方法,设计一种适用于永磁同步电机矢量控制的自抗扰控制器,并从理论上验证了自抗扰控制器对于时间电流谐波的抑制作用,以及针对自抗扰控制器参数众多调参困难的问题,给出一种参数整定方案。最后通过引入所设计的自抗扰控制器,对电机的时间电流谐波进行计算和分析,使电机的附加谐波损耗降低了68.1%,为同类型电机的附加谐波损耗抑制提供了一种有效的方法。

关键词：永磁同步电机自抗扰控制时间电流谐波附加谐波损耗场路耦合联合仿真

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健康体检成年人群单次尿液与肾功能检查结果分析

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首都食品与医药 2024年第1期31卷 101-103页

作者：朱龙飞上海建工医院上海200080

目的对健康体检成年人群单次尿液与肾功能检查结果进行分析,以期为肾脏病的早期筛查提供更多的数据支持。方法该研究选取2023年1月-2023年6月期间在上海建工医院体检中心进行健康体检的14869例次成年体检人群作为研究对象,所有受试者均... 详细信息

目的对健康体检成年人群单次尿液与肾功能检查结果进行分析,以期为肾脏病的早期筛查提供更多的数据支持。方法该研究选取2023年1月-2023年6月期间在上海建工医院体检中心进行健康体检的14869例次成年体检人群作为研究对象,所有受试者均自愿在该院进行尿液和肾功能检查,对其临床资料进行回顾性分析。结果女性单纯血尿检出率、白细胞尿检出率、蛋白尿伴血尿检出率显著高于男性(P<0.05)。女性血清Cr水平显著低于男性(P<0.05)。单纯蛋白尿、单纯血尿、蛋白尿伴血尿、白细胞尿、肾功能减退及肾功能减退伴尿指标异常检出率和血清Cr水平均随着年龄增长而显著增长(P<0.05)。结论普通健康成年人群健康体检中尿异常及肾功能减退均有检出,且指标异常人群以老年人群为主;健康体检中的尿液检查及肾功能检查可作为肾脏疾病早期阶段的筛查方法在临床推广。

关键词：健康体检成年人尿液肾功能肾功能减退

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融合强化学习的DBN跑道侵入风险预测

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中国安全科学学报 2024年第7期34卷 20-27页

作者：吴维吴泽萱王兴隆祝龙飞中国民航大学民航飞联网重点实验室天津300300 中国民航大学空中交通管理学院天津300300

为解决机场跑道侵入事件风险量化难度大、时效性差、精准性低等问题,提升跑道侵入风险预警能力,构建融合强化学习的动态贝叶斯网络(DBN)风险预测模型。首先,结合因果推断理论与灰色关联分析法分析跑道侵入历史事件,识别跑道侵入事件风... 详细信息

为解决机场跑道侵入事件风险量化难度大、时效性差、精准性低等问题,提升跑道侵入风险预警能力,构建融合强化学习的动态贝叶斯网络(DBN)风险预测模型。首先,结合因果推断理论与灰色关联分析法分析跑道侵入历史事件,识别跑道侵入事件风险致因;其次,运用贝叶斯网络(BN)理论挖掘各风险因素间的关联性,并利用皮尔逊线性相关系数量化各因素间的关联关系,构建表征风险传播的致因关系网络;然后,利用三角模糊方法与隐马尔可夫模型(HMMs)优化DBN参数学习机制;最后,利用历史数据验证基于融合强化学习的DBN预测结果准确性。结果表明:基于融合强化学习的DBN预测结果与历史数据统计数值的拟合较好,准确率为84%,与单独DBN预测结果相比准确性提升10%;相比于采用度值评价法,通过互信息识别关键节点可有效提升预测准确率和区分度。

关键词：强化学习动态贝叶斯网络(DBN) 跑道侵入风险预测灰色关联分析

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婴儿泛发性幼年黄色肉芽肿1例

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中国皮肤性病学杂志 2024年第7期38卷 808-810,821页

作者：冉林卉彭斌朱龙飞耿松梅临夏回族自治州人民医院皮肤科甘肃临夏731100 西安交通大学医学院第二附属医院皮肤科陕西西安710004

患儿男,7月龄,全身丘疹结节7个月。出生第2天,患儿头面部、躯干及上肢皮肤出现大小不等的斑疹和斑丘疹,4个月前头颈、胸背部及四肢皮疹增多增大,形成多个蚕豆到鸽卵大小的疣状结节,未予治疗。皮损组织病理示:真皮内界限清楚的肿瘤细胞团... 详细信息

患儿男,7月龄,全身丘疹结节7个月。出生第2天,患儿头面部、躯干及上肢皮肤出现大小不等的斑疹和斑丘疹,4个月前头颈、胸背部及四肢皮疹增多增大,形成多个蚕豆到鸽卵大小的疣状结节,未予治疗。皮损组织病理示:真皮内界限清楚的肿瘤细胞团块,肿瘤细胞以组织样细胞及泡沫细胞为主,可见Touton巨细胞;免疫组织化学染色示:CD68(+)、S100(+)。诊断:泛发性幼年黄色肉芽肿。

关键词：泛发性幼年黄色肉芽肿婴儿

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杜鹃AQP基因家族的鉴定与生物信息学分析

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井冈山大学学报（自然科学版） 2024年第5期45卷 58-64页

作者：刘子怡冯关萍李红霞朱龙飞井冈山大学生命科学学院江西吉安343009 吉安市烟草专卖局(公司) 江西吉安343009

为了研究杜鹃水通道蛋白基因家族的生物学功能,本研究利用生物信息学方法在杜鹃基因组中鉴定了35个水通道蛋白基因。基因位置分析水通道蛋白基因在杜鹃13条染色体上不均匀分布。聚类分析显示杜鹃水通道蛋白可以分为5个亚家族(PIP、TIP、... 详细信息

为了研究杜鹃水通道蛋白基因家族的生物学功能,本研究利用生物信息学方法在杜鹃基因组中鉴定了35个水通道蛋白基因。基因位置分析水通道蛋白基因在杜鹃13条染色体上不均匀分布。聚类分析显示杜鹃水通道蛋白可以分为5个亚家族(PIP、TIP、NIP、SIP和XIP)。启动子响应元件分析发现大部分AQP基因启动子区所含元件与激素调节、光响应和抗逆胁迫等密切相关。共线性分析表明有4对AQP基因出现了片段重复;Ka/Ks(同义替换/非同义替换)结果显示均小于1,表明这些基因经历了较强的纯化选择。本研究为了解杜鹃水通道蛋白家族的功能提供了理论基础。

关键词：杜鹃水通道蛋白基因家族生物信息学

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Alterations of soil aggregates and intra-aggregate organic carbon fractions after soil conversion from paddy soils to upland soils:Distribution,mineralization and driving mechanism

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Pedosphere 2024年第1期34卷 121-135页

作者： longfei KANG Jiamei WU Chunfeng ZHANG Baoguo zhu Guixin CHU College of Life Science Shaoxing UniversityShaoxing 312000China The Key Laboratory of Oasis Eco-agriculture Xinjiang Production and Construction Group/Department of Resources and Environmental SciencesAgronomy CollegeShihezi UniversityShihezi 832000China Hunan Institute of Agricultural Environment and Ecology Changsha 410000China Jiamusi Branch Heilongjiang Academy of Agricultural SciencesJiamusi 154007China

Investigating the impacts of soil conversion on soil organic carbon(OC) content and its fractions within soil aggregates is essential for defining better strategies to improve soil structure and OC sequestration in terrestrial ecosystems. However, the consequences of soil conversion from paddy soil to upland soil for soil aggregates and intra-aggregate OC pools are poorly understood. Therefore, the objective of this study was to quantify the effects of soil conversion on soil aggregate and intra-aggregate OC pool distributions. Four typical rice-producing areas were chosen in North and South China, paired soil samples(upland soil converted from paddy soil more than ten years ago vs. adjacent paddy soil) were collected(0–20 cm) with three replicates in each area. A set of core parameters(OC preservation capacity, aggregate carbon(C) turnover, and biological activity index) were evaluated to assess the responses of intra-aggregate OC turnover to soil conversion. Results showed that soil conversion from paddy soil to upland soil significantly improved the formation of macro-aggregates and increased aggregate stability. It also notably decreased soil intra-aggregate OC pools, including easily oxidized OCa(EOCa), particulate OCa(POCa), and mineral-bound(MOCa) OC, and the sensitivity of aggregate-associated OC pools to soil conversion followed the order: EOCa(average reduction of 21.1%) > MOCa(average reduction of 15.4%) > POCa(average reduction of 14.8%). The potentially mineralizable C(C_(0)) was significantly higher in upland soil than in paddy soil, but the corresponding decay constant(k) was lower in upland soil than in paddy soil. Random forest model and partial correlation analysis showed that EOCa and pH were the important nutrient and physicochemical factors impacting k of C mineralization in paddy soil,while MOCa and C-related enzyme(β-D-cellobiohydrolase) were identified as the key factors in upland soil. In conclusion, this study evidenced that soil conversion

关键词： decay constant easily oxidized organic C macro-aggregate meso-aggregate micro-aggregate mineral-bound organic C particulate organic C potentially mineralizable C

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Numerical study of gain equalization in burst-mode Yb^(3+)-doped fiber amplifier with pulse pump by FDTD method

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Optoelectronics Letters 2021年第8期17卷 496-500页

作者： zhu longfei LI Caiyun LIU Yange XING Dengke ZHANG Luhe zhu Kaiyan WANG Zhi Tianjin Key Laboratory of Optoelectronic Sensor Sensing Network Technology Institute of Modern OpticsNankai UniversityTianjin 300350China

The amplifying dynamics of the pulse burst in Yb^(3+)-doped fiber amplifier(YDFA)with high-power pulse pump is numerically analyzed by a finite-difference time-domain(FDTD)*** numerical simulations show that the amplitude uniformity of the amplified pulse burst can be modified by adjusting the parameters of pump,such as relative delay and *** optimizing the pump parameters,we can reduce the gain difference between the pulses in a burst and improve the efficiency of coherent pulse stacking based on Gires-Tournois interferometers(GTIs).These results can be applied to the design of high energy ultra-short pulse amplifiers based on burst-mode amplification and coherent pulse stacking technology.

关键词： pump amplifier pulse

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Long-term thinning decreases the contribution of heterotrophic respiration to soil respiration in subalpine plantations

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Journal of Forestry Research 2024年第3期35卷 189-204页

作者： longfei Chen Zhibin He Wenzhi Zhao Xi zhu Qin Shen Mingdan Song Zhengpeng Li Junqia Kong Shuping Yang Yuan Gao Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000People's Republic of China State Forestry Administration Key Laboratory of Forest Resources and Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China Academy of Agriculture and Forestry Sciences Qinghai UniversityXining 810000People's Republic of China College of Landscape Architecture Zhejiang A&F UniversityHangzhou 310000People's Republic of China

Interest in the dynamics of soil respiration(R_(S))in subalpine forest ecosystems is increasing due to their high soil carbon density and potential sensitivity to environmental ***,as a principal silvicultural practice,the long-term impacts of thinning on R_(S) and its heterotrophic and autotrophic respiration components(R_(h) and Ra,respectively)in subalpine plantations are poorly understood,espe-cially in winter.A 3-year field observation was carried out with consideration of winter CO_(2) efflux in middle-aged sub-alpine spruce plantations in northwestern China.A trench-ing method was used to explore the long-term impacts of thinning on Rs,Rn and R_(a).Seventeen years after thinning,mean annual Rs,Rn and R_(a) increased,while the contribu-tion of R_(h) to R_(s) decreased with thinning *** significantly decreased winter R,because of the reduction in R_(n) but had no significant effect on *** temperature sensitivity(Q_(10))of R_(h) and R_(a) also increased with thinning intensity,with lower Q_(10) values for R_(h)(2.1-2.6)than for Ra(2.4-2.8).The results revealed the explanatory variables and pathways related to R_(n) and R_(a) *** increased soil moisture and nitrate nitrogen(NO_(3)^(-)-N),and the enhanced nitrogen and water availability promoted R_(h) and R_(a) by improving fine root biomass and microbial *** results highlight the positive roles of NO_(3)^(-)-N in stimulating R_(s) components following long-term ***,applications of nitrogen fertilizer are not recommended while thinning subalpine spruce plantations from the perspective of reducing soil CO_(2) *** increased Q_(10) values of R_(s) components indicate that a large increase in soil CO_(2) emissions would be expected following thinning because of more pronounced climate warming in alpineregions.

关键词： Heterotrophic respiration Autotrophic respiration Long-term thinning impacts Cold seasons Subalpine plantations Temperature sensitivity

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Efficient epoxidation of propylene over non-noble nickel-based catalyst promoted by alkali metals

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Science China Chemistry 2024年第11期67卷 3697-3705页

作者： Wenqian Li Wanting Li Xinxin Cao longfei Chen Yibo Qin Yanfeng zhu Yanfei Zhang Gai Miao Lingzhao Kong Jiong Li Xinqing Chen State Key Laboratory of Low Carbon Catalysis and Carbon Dioxide Utilization CAS Key Laboratory of Low-carbon Conversion Science and Engineering Shanghai Advanced Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences School of Environmental Science and Engineering Suzhou University of Science and Technology Shanghai Synchrotron Radiation Facility Zhangjiang National Lab Shanghai Advanced Research Institute Chinese Academy of Sciences

The application of non-noble metal catalysts in the catalytic direct gas-phase epoxidation of propylene with H2and O2to produce propylene oxide is valuable and challenging. The introduction of alkali metal promoters is one of the effective methods to improve the catalytic activity of catalysts. Herein, a series of alkali metal（Li, Na, K, Rb, and Cs）-promoted Ni/TS-1 catalysts were prepared to deeply understand the effect of alkali metals on the structure-activity relationship for gas-phase epoxidation of propylene. Among them, the Na-Ni/TS-1 catalyst exhibits the highest catalytic activity(propylene conversion of 7.35% and PO formation rate of 157.9 g h-1kgcat-1) and the best stability（long-term stability exceeding 140 h at 200 °C）. X-ray absorption and photoelectron spectroscopy revealed that the electronic structure of Ni can be tuned by the addition of alkali metal ***3-TPD-MS, CO2-TPD-MS, and C3H6-TPD-MS results indicate that the acidity of the catalyst can also be adjusted by the introduction of alkali metal, whereas the Na-Ni/TS-1 catalyst exhibits the strongest C3H6adsorption capacity. Thus, the suitable acid-base properties, unique electronic properties of Ni species, and the strongest propylene adsorption capacity resulted in improved propylene gas-phase epoxidation activity of Na-Ni/TS-1 catalyst. This study not only provides a new strategy for the practical application of nickel-based catalysts in the gas-phase epoxidation of propylene but also provides insights into the promoting effect of alkali metals.

关键词： propylene epoxidation Ni/TS-1 catalyst alkali metal precipitating agents

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