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基于层级分解的前围声学包多目标优化

振动与冲击 2025年第3期44卷 267-277页

作者：杨帅吴宪薛顺达同济大学汽车学院上海201804 拾音汽车科技(上海)有限公司上海201100

搭建了前围声学包多层级目标分解架构,提出GAPSO-RBFNN(genetic algorithm particle swarm optimization-radial basis function neural network)预测模型,并将其应用于多层级目标分解架构。将材料数据库、覆盖率、泄漏量作为优化的变... 详细信息

搭建了前围声学包多层级目标分解架构,提出GAPSO-RBFNN(genetic algorithm particle swarm optimization-radial basis function neural network)预测模型,并将其应用于多层级目标分解架构。将材料数据库、覆盖率、泄漏量作为优化的变量范围,以PBNR(power based noise reduction)均值作为约束,以质量和成本作为优化目标,采用非支配排序遗传算法(nondominated sorting genetic algorithm II,NSGA-II)进行多目标优化,得到Pareto多目标解集。并从中选取满足设计目标的最佳组合方案(材料组合、覆盖率、前围过孔密封方案选型)。结果显示,该模型最终的优化结果与实测结果接近,误差分别为0.35%,1.47%,1.82%,相较于初始声学包方案,优化后的结果显示,PBNR均值提升3.05%,其质量降低52.38%,成本降低15.15%,验证了所提方法的有效性和准确性。

关键词： GAPSO-RBFNN 声学包 PBNR NSGA-II Pareto多目标解集

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一种基于光纤环镜的保偏光纤对轴方法

光电子·激光 2025年第3期36卷 268-275页

作者：胡曙阳吴娴张芸山翟天瑞北京工业大学物理与光电工程学院

本文提出并实现了一种新颖的基于光纤环镜(fiber loop mirror, FLM)的保偏光纤(polarization maintaining fiber, PMF)对轴方法。该方法把两段待熔接的保偏光纤接入3 dB耦合器，将它们的端面对接，构成含两段保偏光纤的环镜。对环镜的... 详细信息

本文提出并实现了一种新颖的基于光纤环镜(fiber loop mirror, FLM)的保偏光纤(polarization maintaining fiber, PMF)对轴方法。该方法把两段待熔接的保偏光纤接入3 dB耦合器，将它们的端面对接，构成含两段保偏光纤的环镜。对环镜的透过光谱进行数据处理和分析，计算出对轴角度，从而实现保偏光纤的对轴。本文推导了含有两段保偏光纤的光纤环镜的透过率函数，分析得到了根据透过率光谱反演对轴角度的方法，并进行了数值仿真和实验研究。该方法直接根据偏振轴的夹角来定轴，适用于所有类型的保偏光纤，具有实际应用价值。

关键词：保偏光纤(PMF) 偏振对轴光纤环镜(FLM) 光谱分析

黄土区深厚土壤严重干化后再植苜蓿地的土壤水分入渗特征

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草业学报 2025年第1期34卷 66-79页

作者：滕远马兵吴贤忠汪星吕雯任鸿武汪治同宁夏大学林业与草业学院宁夏银川750021 林木资源高效生产全国重点实验室宁夏银川750021 兰州城市学院城市环境学院甘肃兰州730070 宁夏大学生态环境学院宁夏银川750021 阿拉善左旗宗别立镇综合保障和技术推广中心内蒙古阿拉善左旗750300

自然降水是半干旱黄土区土壤水分的唯一来源。为了探究黄土丘陵区深厚土壤干化背景下再种植深根系、多年生植物后的土壤水分入渗对降雨的响应特征,本研究在宁夏南部王洼水土保持试验站采用野外实地大规格土柱模拟干燥化土壤的方法种植苜... 详细信息

自然降水是半干旱黄土区土壤水分的唯一来源。为了探究黄土丘陵区深厚土壤干化背景下再种植深根系、多年生植物后的土壤水分入渗对降雨的响应特征,本研究在宁夏南部王洼水土保持试验站采用野外实地大规格土柱模拟干燥化土壤的方法种植苜蓿,试验分析2022-2023年每年的3-10月定位观测数据。结果表明:1)能有效产生土壤水分入渗的降雨次数仅占总降雨次数的41.67%,降雨量与入渗量占比为:小雨入渗量占其降雨量的15.89%,中雨入渗量占其降雨量的35.63%,大雨入渗量占其降雨量的52.20%,暴雨入渗量占其降雨量的61.50%,入渗量随着降雨量的增大呈增大的趋势;2)降雨入渗深度小于30 cm的降雨次数占总降雨次数的76.04%,入渗深度在30~80 cm的降雨次数占总降雨次数的18.75%,入渗深度在80 cm以上的降雨次数占总降雨次数的5.21%;3)深层土壤干化背景下种植苜蓿,一龄苜蓿地月尺度土壤剖面水分呈现增加趋势,二龄苜蓿地月尺度土壤剖面水分呈减小趋势,逐月降雨入渗深度(Zm)随月降雨量(Pm)增加呈二次函数增大变化:Z_(m)=-0.0101P_(m)^(2)+3.9426P_(m)(R^(2)=0.9895)。本研究可为黄土高原区深厚土壤严重干化后再植深根系、多年生植物及其可持续发展提供理论与数据支撑。

关键词：黄土区土壤干化苜蓿土壤水分降雨入渗

Highly Cis-1,4 Selective Polymerization of Conjugated Dienes Catalyzed by ^-heterocyclic Carbene-ligated Neodymium Complexes

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Chinese Journal of Polymer Science 2020年第12期38卷 1305-1312页

作者： Shu Zhang Na wu Yi-xian wu State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Neodymium complexes containing N heterocyclic carbene(NHC)ligands,NdCl5[1,3,R(NCH=)2C]-THF,(Nd1:R=2,6-Pr2C6H3,x=0;Nd2:R=2,6-Et2C6H3,x=1;Nd3:R=2.4,6-Me3C6H2,x=1)were synthesized and employed as precatalysts for the coordination polymerization of conjugated dienes(butadiene and isoprene).In combination with trisobutylaluminium(TIBA),Nd1 promoted butadiene polymerization to produce extremely high cis-1,4(up to 99.0%)polybutadienes with high molecular weight(Mw=250-780 kg·mol 1).The Nd1/TIBA catalytic system also exhibited both high catalytic activity and cis-1,4 selectivity(up to 97.8%)for isoprene *** catalytic activity,molecular weight and molecular weight distribution of resulting polydienes were directly influenced by Al/Nd molar ratio,aging method,and polymerization *** interestingly,the high cis-1,4 selectivity of the catalyst towards butadiene and isoprene kept almost unchanged under different reaction *** cis-1,4 polyisoprenes with high molecular weight(Mw=210-530 kg·mol 1)and narrow molecular weight distribution (Mw/Mn=1.9-2.7)as well as high cis-1.4 selectivity(-~97%)could be synthesized by using the aged Nd1/TIBA catalytic system in the presence of isoprene(100 equivalent to Nd)at low AlNd molar ratios of *** with low molecular weights(Mw=12-76 kg·mol-7)and narrow molecular weight distributions (Mw/Mn=1.7-2.6)were obtained by using Nd2 and Nd3 as precatalysts,indicating that the molecular weight of resulting polyisoprenes can be adjusted by changing the substitutes of ligand in Nd complex.

关键词： Neodymium complex N heterocydic carbene igand Coordination polymerization Cis-14 sletivity Aging method

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基于可重参的自适应激活函数算法

软件导刊 2025年第2期24卷 83-88页

作者：吴限陶青川四川大学电子信息学院四川成都610065

经典轻量化网络的特征提取能力存在一定不足,在推理阶段几乎不引入额外计算的基础上,对可重参自适应激活函数进行研究,提出RepAct激活函数。RepAct的自适应可重参多分支结构通过不同特征信息的分支权重进行自适应学习,显著提升了轻量化... 详细信息

经典轻量化网络的特征提取能力存在一定不足,在推理阶段几乎不引入额外计算的基础上,对可重参自适应激活函数进行研究,提出RepAct激活函数。RepAct的自适应可重参多分支结构通过不同特征信息的分支权重进行自适应学习,显著提升了轻量化网络的学习能力。在各经典轻量化CNN和ViT网络中,RepAct可以有效提升分类任务的精度。在ImageNet100上,MobileNetV3-Small的Top-1准确率提升了6.9%;在Cifar100上,MobileNetV3-Small的Top-1准确率提升了5.71%,超越了其他主流的激活函数。此外,通过GradCAM可视化,揭示了RepAct提升网络特征提取能力的原因。

关键词：自适应激活函数可重参结构轻量化网络

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Therapy of acute severe pancreatitis awaits further improvement

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World Journal of Gastroenterology 1998年第4期4卷 13-14页

作者： wu xianZhong Tianjin Inst. of Acute Abdom. Dis. Tianjin 300100 China Faculty of Medicine Shenyang Medical College China Department of Surgery China Chinese Assoc. Intgd. Chinese W. M. China Tianjin Inst. of Acute Abdom. Dis. Tianjin 300100 Nankai District China

ＴｈｅｒａｐｙｏｆａｃｕｔｅｓｅｖｅｒｅｐａｎｃｒｅａｔｉｔｉｓａｗａｉｔｓｆｕｒｔｈｅｒｉｍｐｒｏｖｅｍｅｎｔＷＵＸｉａｎＺｈｏｎｇＳｕｂｊｅｃｔｈｅａｄｉｎｇｓｐａｎｃｒｅａｔｉｔｉｓ／ｔｈｅｒａｐｙ；ｐａｎｃ... 详细信息

ＴｈｅｒａｐｙｏｆａｃｕｔｅｓｅｖｅｒｅｐａｎｃｒｅａｔｉｔｉｓａｗａｉｔｓｆｕｒｔｈｅｒｉｍｐｒｏｖｅｍｅｎｔＷＵＸｉａｎＺｈｏｎｇＳｕｂｊｅｃｔｈｅａｄｉｎｇｓｐａｎｃｒｅａｔｉｔｉｓ／ｔｈｅｒａｐｙ；ｐａｎｃｒｅａｔｉｔｉｓ／ｄｒｕｇｔｈｅｒ...

关键词： pancreatitis/therapy pancreatitis/drug therapy pancreatitis/mortality pancreatitis/complication TCMWM therapy

A Survey of Image Synthesis and Editing with Generative Adversarial Networks

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Tsinghua Science and Technology 2017年第6期22卷 660-674页

作者： xian wu Kun Xu Peter Hall TNList and the Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China the Department of Computer Science University of BathBathUK

This paper presents a survey of image synthesis and editing with Generative Adversarial Networks（GANs）. GANs consist of two deep networks, a generator and a discriminator, which are trained in a competitive way. Due to the power of deep networks and the competitive training manner, GANs are capable of producing reasonable and realistic images, and have shown great capability in many image synthesis and editing *** paper surveys recent GAN papers regarding topics including, but not limited to, texture synthesis, image inpainting, image-to-image translation, and image editing.

关键词： image synthesis image editing constrained image synthesis generative adversarial networks imageto-image translation

Effect on greenhouse gas balance of converting rice paddies to vegetable production

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Acta Geochimica 2017年第3期36卷 353-354页

作者： Lei wu xian wu Ronggui Hu College of Resources and Environment Huazhong Agricultural University Wuhan 430070 China

Rice paddies are increasingly being converted to vegetable production due to economic benefits related,in part,to changes in demand during recent ***,we implemented a parallel field experiment to simultaneously measure annual emissions of CH_4and N_2O,and soil organic carbon(SOC)stock changes,in rice paddies(RP),rice paddy–converted conventional vegetable fields(CV),and rice paddy–converted greenhouse vegetable fields(GV).Changing from rice to vegetable production reduced CH_4emissions by nearly 100%,and also triggered substantial N_2O ***,annual N_2O emissions from GV significantly exceeded those from CV due to lower soil p H and higher soil *** SOC losses occurred after one year of cultivation of RP,CV,and GV,contributing an important share(3.4%,32.2%,and 10.3%,respectively)of the overall global warming potential(GWP)*** decline in CH_4emissions outweighed the increased N_2O emissions and SOC losses in CV and GV,leading to a 13%–30%reduction in annual GWP as compared to *** results suggest that large-scale expansion of vegetable production at the expense of rice paddies is beneficial for mitigating climate change in terms of the overall GWP.

关键词： Greenhouse gas balance Land management change CH4 N2O Soil organic carbon

On Fixed Point and Almost Fixed Point Problems of Lower Semicontinuous Type Multivalued Mappings

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Acta Mathematica Sinica,English Series 2005年第5期21卷 1027-1034页

作者： Liang Yu LUAN xian wu Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 P. R. China Department of Mathematics Yunnan Normal University Kunming 650092 P. R. China

In the present paper, some new almost fixed point theorems and fixed point theorems for lower semicontinuous type multivalued mappings are obtained in metrizable H-spaces.

关键词： Lc.-metric space H-space Lower semicontinuous multivalued mapping Locally-uniformly weak lower semicontinuous multivalued mapping