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基于多尺度特征提取的层次多标签文本分类方法

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郑州大学学报(理学版) 2025年第2期57卷 24-30页

作者：武子轩王烨于洪重庆邮电大学计算智能重庆市重点实验室

针对现有的特征提取方法忽略文本局部和全局联系的问题，提出了基于多尺度特征提取的层次多标签文本分类方法。首先，设计了多尺度特征提取模块，对不同尺度特征进行捕捉，更好地表示文本语义。其次，将层次特征嵌入文本表示中，得到具... 详细信息

针对现有的特征提取方法忽略文本局部和全局联系的问题，提出了基于多尺度特征提取的层次多标签文本分类方法。首先，设计了多尺度特征提取模块，对不同尺度特征进行捕捉，更好地表示文本语义。其次，将层次特征嵌入文本表示中，得到具有标签特征的文本语义表示。最后，在标签层次结构的指导下对输入文本构建正负样本，进行对比学习，提高分类效果。在WOS、RCV1-V2、NYT和AAPD数据集上进行对比实验，结果表明，所提模型在评价指标上表现出色，超过了其他主流模型。此外，针对层次分类提出层次Micro-F1和层次Macro-F1指标，并对模型效果进行了评价。

关键词：层次多标签文本分类多尺度特征提取对比学习层次Micro-F1 层次Macro-F1

Comparisons and applications of numerical simulation methods for predicting aerodynamic heating around complex configurations

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Acta Mechanica Sinica 2011年第3期27卷 339-345页

作者： jin-Ling Luo hong-Lin Kang Jian Li wu-Ye Dai Northwestern Polytechnical University 710072 Xi'an China Beijing Electro-Mechanical Engineering Institute100074 Beijing China

Numerical simulation methods of aerodynamic heating were compared by considering the inuence of numerical schemes and turbulence models,and attempting to investigate the applicability of numerical simulation methods on predicting heat flux in engineering applications. For some typical cases provided with detailed experimental data,four spatial schemes and four turbulence models were adopted to calculate surface heat flux. By analyzing and comparing,some inuencing regularities of numerical schemes and turbulence models on calculating heat flux had been acquired. It is clear that AUSM＋-up scheme with rapid compressibilitymodified high Reynolds number k鈥撓？model should be appropriate for calculating heat flux. The numerical methods selected as preference above were applied to calculate the heat flux of a 3-D complex geometry in high speed turbulent flows. The results indicated that numerical simulation can capture the complex flow phenomena and reveal the mechanism of aerodynamic heating. Especially,the numerical result of the heat flux at the stagnation point of the wedge was well in agreement with the prediction of Kemp鈥揜iddel formula,and the surface heat flux distribution was consistent with experiment results,which implied that numerical simulation can be introduced to predict heat flux in engineering applications.

关键词： Aerodynamic heating . Complex configurations . Numerical simulation

Landscape design method for a green community based on green building design theory

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第9期11卷 691-700页

作者： hong-feng GUO Jian GE Miao YUE Xiao ZHOU wu jin Architectural Design and Research Institute Zhejiang University Hangzhou 310027 China Department of Architecture Zhejiang University Hangzhou 310058 China

Landscape design for a green community should be favorable for the ambient ecological environment and for enhancement of both the local climate of a residential area and the environmental quality of life. This paper presents optimization methods for plant landscape design that take account of results of comparisons of noise reduction effects, heat island temperature decreases and effects on ventilation. These methods are based on different plant configurations and various luminous environments, such as exterior sunshine and shaded areas after the simulation of exterior luminous, acoustic and thermal environments of a residential area using the analytic software ECOTECT, CADNA/A, and PHEONICS. Three different types of residential buildings are simulated including a faculty apartment in the Xixi Campus of Zhejiang University, the Huaqing Villa and the Gangwan Jiayuan faculty apartment of Zhejiang University, China, based on green building design theory. In addition, the methods and process flow of landscape design of green residential areas are also described for the improvement of the exterior physical living environment.

关键词： Landscape design Green community Green building Exterior physical environment

Co-production of hydrogen, oxygen, and electricity via an integrated solar-driven system with decoupled water electrolyzer and Na-Zn ion battery

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Journal of Energy Chemistry 2025年第1期100卷 621-627页

作者： Fei Lv Longjie Liu Jiazhe wu Pengfei Wang Lixia Pan Dengwei jing Yubin Chen International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University

Combining water electrolysis and rechargeable battery technologies into a single system holds great promise for the co-production of hydrogen （H2） and ***,the design and development of such systems is still in its ***,an integrated hydrogen-oxygen （O2）-electricity co-production system featuring a bipolar membrane-assisted decoupled electrolyzer and a Na-Zn ion battery was established with sodium nickelhexacyanoferrate （NaNiHCF） and Zn2+/Zn as dual redox *** decoupled electrolyzer enables to produce H2and O2in different time and space with almost 100%Faradaic efficiency at 100 mA ***,the charged NaNiHCF and Zn electrodes after the electrolysis processes formed a Na-Zn ion battery,which can generate electricity with an average cell voltage of 1.75 V at 10 m A *** connecting Si photovoltaics with the modular electrochemical device,a well-matched solar driven system was built to convert the intermittent solar energy into hydrogen and electric energy with a solar to hydrogen-electricity efficiency of 16.7%,demonstrating the flexible storage and conversion of renewables.

关键词： Hydrogen Electricity Decoupled water electrolyzer Na-Zn ion battery Solar energy

Enteromorpha prolifera polysaccharide-Fe(Ⅲ) complex promotes intestinal development as a new iron supplement

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Science China Life Sciences 2025年第1期 219-231页

作者： Yingying Feng Yuying wu Jialu Wang Zhenglin Dong Qian Yu Shuangshuang Xia Chunxue Liu Haihua Wang Xin wu Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences CAS Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of Sciences ANYOU Biotechnology Group Co.Ltd Qingdao Seawin Biotech Group Co. LTD

Iron is a crucial micronutrient, and its deficiency can have detrimental effects on the health of infants. Dietary polysaccharide-iron(Ⅲ) complexes(PICs) are promising for addressing iron deficiency due to their minimal adverse reactions and high iron absorption rate. This study aimed to investigate the effects of dietary Enteromorpha prolifera polysaccharide-Fe(Ⅲ) complex(EP-Fe) on newborns, using 3-day weaned piglets as the iron-deficiency model. Results showed that EP-Fe improved iron levels and promoted intestinal development in piglets. Transcriptome sequencing revealed that EP-Fe increased the survival of intestinal epithelial cells under hypoxia by upregulating the expression of genes that promote the development of the vascular system. Additionally, EP-Fe enhanced the mucosal barrier functions by inhibiting myosin light chain kinase(MLCK)/phosphorylated myosin light chain(p-MLC) signaling pathway to increase the expression of intestinal tight junction proteins. Furthermore, the 16S r RNA gene sequencing of gut microbiota showed that EP-Fe promoted the enrichment of Bacteroides＿fragilis and other gut microbes that can metabolize carbohydrates. In conclusion, EP-Fe is an effective iron supplement for newborns, and it can be developed as a comprehensive nutritional supplement.

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Vertical gradients of neutral winds observed by ICON and estimated by the Horizontal Wind Model during the geomagnetic storm on August 26−28,2021

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Earth and Planetary Physics 2025年第1期9卷 69-80页

作者： JiaWei wu Chao Xiong YuYang Huang YunLiang Zhou Department of Space Physics School of Electronic InformationHubei Luojia LaboratoryWuhan UniversityWuhan 430072China

The Michelson Interferometer for Global High-resolution Thermospheric Imaging(MIGHTI)onboard the Ionospheric Connection Explorer(ICON)satellite offers the opportunity to investigate the altitude profile of thermospheric *** this study,we used the red-line measurements of MIGHTI to compare with the results estimated by Horizontal Wind Model 14(HWM14).The data selected included both the geomagnetic quiet period(December 2019 to August 2022)and the geomagnetic storm on August 26-28,*** the geomagnetic quiet period,the estimations of neutral winds from HWM14 showed relatively good agreement with the observations from *** to the ICON observations,near the equator,zonal winds reverse from westward to eastward at around 06:00 local time(LT)at higher altitudes,and the stronger westward winds appear at later LTs at lower *** around 16:00 LT,eastward winds at 300 km reverse to westward,and vertical gradients of zonal winds similar to those at sunrise hours can be *** the middle latitudes,zonal winds reverse about 2-4 h *** winds vary more significantly than zonal winds with seasonal and latitudinal *** to the ICON observations,in the northern low latitudes,vertical reversals of meridional winds are found at 08:00-13:00 LT from 300 to 160 km and at around 18:00 LT from 300 to 200 km during the June *** reversals of meridional winds are found at 04:00-07:00 LT from 300 to 160 km and at 22:00-02:00 LT from 270 to 200 km during the December *** the southern low latitudes,meridional wind reversals occur at 08:00-11:00 LT from 200 to 160 km and at 21:00-02:00 LT from 300 to 200 km during the June *** the December solstice,reversals of the meridional wind appear at 20:00-01:00 LT below 200 km and at 06:00-11:00 LT from 300 to 160 *** the northern middle latitudes,the northward winds are dominant at 08:00-14:00 LT at 230 km during the June *** winds persist until

关键词： horizontal neutral winds vertical gradients Ionospheric Connection Explorer satellite Horizontal Wind Model 14 geomagnetic storm

A quantum-search-based multi-classifier for image recognition

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 21-31页

作者： Lu Liu Xingyu wu Lufan Zhang Chuan Wang School of Artificial Intelligence Beijing Normal University Applied Optics Beijing Area Major Laboratory Beijing Normal University

The multi-class classification of images is a pivotal challenge within the realm of image processing. As the volume of visual data continues to expand, there is a burgeoning interest in harnessing the unique capabilities of quantum computation to augment the efficiency of classification tasks. However, many existing methods for training quantum image multi-classifiers parallel classical machine learning techniques, where the requisite circuit measurements increase linearly with the volume of training data. This work introduces a novel approach for training a quantum image multi-classifier based on the quantum search algorithm. We have meticulously conducted rigorous experiments on a handwritten digit dataset, a classic benchmark in the field. The results have been meticulously compared with previous works, and the comparative analysis not only validates the efficiency of our proposed approach, requiring only O(N/b) measurements during training, but also highlights a significant quadratic speedup of the algorithm.

关键词： quantum computation image recognition quantum search algorithm

Effect of electric field on the spectrum and the persistent current of a quantum ring with two electrons （II） additional effect of a charged impurity

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Chinese Physics B 2008年第8期17卷 3026-3034页

作者： wu hong Department of Physics School of Sciences Jimei University Xiamen 361021 China

This paper studies the effect of a charged impurity together with or without an external homogeneous electric field on a quantum ring threaded by a magnetic field B and containing two electrons. The potential caused by the impurity has been plotted which is helpful to the understanding of the electronic structures inside the ring. The deep valley appearing in the potential curve is the source of localization, which affects seriously the Aharonov-Bohm oscillation （ABO） of the energy and persistent current. It also causes the fluctuation of the total orbital angular momentum L of the pair of electrons. It is found that the appearance of the impurity reduces the domain of the fractional ABO. During the increase of B, the domain of the integral ABO may appear earlier when B is even quite small. The transition from the localized states to extended states has also been studied. Furthermore, it has deduced a set of related formulae for a transformation, by which an impurity with a charge ep placed at an arbitrary point Rp is equivalent to an impurity with a revised charge ep placed at the X-axis with a revised radial distance Rp. This transformation facilitates the calculation and make the analysis of the physical result clearer.

关键词： charged impurity quantum ring ABO potential

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亚健康状态人群的脉象图特征分析

中西医结合学报 2012年第10期10卷 1099-1105页

作者：鉏桂祥陈清光许家佗于波张敏崔龙涛吴宏进费兆馥上海中医药大学费兆馥名师研究室上海201203 上海中医药大学附属曙光医院内分泌科上海201203

目的:研究不同健康状态及亚健康各证型的脉象图参数,探求评价亚健康状态的特征性脉象图指标。方法:运用"健康状态评价问卷H20.V2009"对1275例无明确急慢性疾病者进行健康状态评估,并分为健康组和亚健康组,依据"亚健康状态辨证依据V2010"... 详细信息

目的:研究不同健康状态及亚健康各证型的脉象图参数,探求评价亚健康状态的特征性脉象图指标。方法:运用"健康状态评价问卷H20.V2009"对1275例无明确急慢性疾病者进行健康状态评估,并分为健康组和亚健康组,依据"亚健康状态辨证依据V2010",对亚健康者进行辨证分型。另设明确诊断的患有心血管疾病的患者121例作为对照。用YJJ-101亚健康脉象监测系统采集脉象,分析主波幅度(amplitude of main wave,h1),重搏波前波幅度(amplitude of front wave,h3),重搏波幅度(amplitude of repeat wave,h5),主波上1/3处宽度(1/3width of main wave,w1),主波上1/5处宽度(1/5width of main wave,w2),左心室快速射血期时值(time of rapid ejection phase,t1),脉动周期(period of pulse,t),脉象图总面积(square of pulse diagram,S)、收缩期面积(area in systole,As)、舒张期面积(area in diastole,Ad),采脉压力(pulse pressure,Pp)和h3/h1、h5/h1、w1/t、w2/t、h1/t1比值等。结果:健康组、亚健康组与疾病组3组比较:与健康组相比,亚健康组w1/t、w2/t增高,Pp、h1、h5、h5/h1、S、As、Ad降低;与疾病组相比,亚健康组Pp、h5/h1增高,h1、w2/t、S、As降低。健康组、实证组与虚证组3组比较:与健康组相比,实证组与虚证组均表现为h3/h1、w1、w1/t、w2/t增高,h1、h5、h1/t1、h5/h1降低。健康组与各证候组比较:各证候组间比较,脉象图参数h1、h5在肝郁组、阴虚组、气虚组、实热组依次降低,脉象图参数h3/h1、w1/t在肝郁组、实热组、阴虚组、气虚组依次升高,肾虚组脉象图指标h1显著高于健康组及其他证候组。结论:不同健康状态、亚健康不同类别及各证型的脉象图参数存在较明显差异,脉象图特征指标可作为客观评价不同健康状态、亚健康分类量化诊断、辨证分型研究的实验依据之一。

关键词：亚健康状态脉象脉象图证候辨证临床试验