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一种基于柱面镜聚焦系统的高灵敏度全谱光谱仪

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光谱学与光谱分析 2025年第1期45卷 222-230页

作者：陈吉文陈作儿赵迎北方工业大学电气与控制工程学院北京100144

很多元素的最灵敏谱线主要分布在紫外波段。一些常被作为检测对象的重要元素,例如C、P和S,其谱线甚至位于200 nm以下的真空紫外波段。然而真空紫外波段内的辐射极易受空气吸收而无法在空气中传输。因此为了适用于紫外波段各谱线的检测,... 详细信息

很多元素的最灵敏谱线主要分布在紫外波段。一些常被作为检测对象的重要元素,例如C、P和S,其谱线甚至位于200 nm以下的真空紫外波段。然而真空紫外波段内的辐射极易受空气吸收而无法在空气中传输。因此为了适用于紫外波段各谱线的检测,常使用光程短、系统精简的罗兰圆光学系统作为光谱仪的色散系统,并且在进行检测分析时,还需对设备腔体内部建立相对真空的环境进行实验,进而减小实验环境对真空紫外波段内各谱线强度的削弱作用。然而即使在该条件下,P和S这两种元素在真空紫外波段的谱线灵敏度仍然较弱。为此为了实现真空紫外波段范围内的高灵敏度,本研究在距离像面前30 mm处位置设计了一个柱面镜聚焦系统。其采用了材料为CaF_(2)、中心厚度为5 mm以及弧矢面曲率半径为22.06 mm的柱面镜作为核心部件。并利用仿真软件Zemax对设计的光学系统进行仿真与优化,以及从非序列模式下的辐射照度仿真结果可知,柱面镜聚焦系统在几乎不影响分辨率的情况下对各波长成像灵敏度有较大的提升。最后以中低合金钢为检测样品,使用电火花激发光源对样品中各元素在紫外波段内的各谱线进行激发,进而验证光谱仪的各项性能:通过一次拟合、参比拟合以及二次拟合,建立每个元素谱峰强度和实际含量之间的数学模型,并算得各元素的拟合优度R^(2)均在0.99以上;柱面镜聚焦系统显著提高了设备在真空紫外波段的灵敏度,响应提高了1倍以上。实验结果表明,柱面镜聚焦系统的设计方法对于提升罗兰圆色散系统的灵敏度具有一定的参考价值。

关键词：紫外光谱罗兰圆光学系统柱面镜灵敏度拟合优度

基于卷积神经网络的财务困境预测:公司财报的图像化

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管理工程学报 2025年第1期39卷 46-62页

作者：赵琪徐维军季昱丞张卫国华南理工大学工商管理学院大湾区数智金融与风险管理研究基地

本文提出了一个端到端的深度学习模型来预测中国上市公司的财务困境,通过将公司基本面数据图像化,探究了深度卷积神经网络(CNN)能否直接从图像化的原始财务数据中自动提取信息,以做出媲美甚至超过借助人类专家知识生成的财务困境预测。... 详细信息

本文提出了一个端到端的深度学习模型来预测中国上市公司的财务困境,通过将公司基本面数据图像化,探究了深度卷积神经网络(CNN)能否直接从图像化的原始财务数据中自动提取信息,以做出媲美甚至超过借助人类专家知识生成的财务困境预测。将来自财务报表中的原始财务项目转化为彩色图像后,深度学习模型可以直接从对应公司的财务项目图像中得出对未来财务困境的准确预测,而无需人类专家事先根据会计专业知识挑选财务项并定义财务指标。实证结果表明,相比使用单一年份的财务数据(灰度图像),使用过去3年的财务数据(彩色图像)有助于提高深度学习模型的预测性能。此外,从原始数据中得出预测的深度学习模型能够达到与“人工选取财务指标+传统机器学习模型”相当的性能。进一步的研究表明,将本文提出的深度学习模型与传统机器学习模型结合起来,可以达到比二者单独使用时更准确的预测性能。

关键词：深度学习卷积神经网络财务困境财务指标

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Use of compositional and combinatorial nanomaterial libraries for biological studies

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Science Bulletin 2016年第10期61卷 755-771页

作者： Zhaoxia ji Center for Environmental Implications of Nanotechnology California Nano Systems Institute University of California

Abstract The rapid development and production of nanomaterials has created some concerns about their potential hazard on the environment, human health and safety. However, since the list of materials that may gen- erate such concerns is very long, it is impossible to test them all. It is therefore usually recommended to use some small compositional nanomaterial libraries to perform ini- tial toxicity screening, based on which combinatorial libraries are then introduced for more in-depth studies. All nanomaterials in the compositional and combinatorial libraries must be rigorously characterized before any bio- logical studies. In this review, several major categories of physicochemical properties that must be characterized are discussed, along with different analytical techniques that are commonly used. Some case studies from the University of California Center for Environmental Implications of Nanotechnology are also chosen to demonstrate the effec- tive use of compositional and combinatorial nanomaterials libraries to identify the role of some key physicochemical properties and to establish true quantitative structure-ac- tivity relationships. Examples on how to use the knowledge generated from those studies to design safer nanomaterials for improved biological applications are also presented.

关键词： Nanomaterial Physicochemical property Characterization Nanotechnology Toxicity Compositional library Combinatoriallibrary

SIF-based fracture criterion for interface cracks

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Acta Mechanica Sinica 2016年第3期32卷 491-496页

作者： Xing ji School of Aerospace Engineering and Applied Mechanics Tongji University

The complex stress intensity factor K governing the stress field of an interface crack tip may be split into two parts, i.e.,■ and s^（-iε）, so that K = ■ s^（-iε）, s is a characteristic length and ε is the oscillatory index. ■ has the same dimension as the classical stress intensity factor and characterizes the interface crack tip field. That means a criterion for interface cracks may be formulated directly with■, as Irwin（ASME J. Appl. Mech. 24：361–364, 1957） did in 1957 for the classical fracture mechanics. Then, for an interface crack,it is demonstrated that the quasi Mode I and Mode II tip fields can be defined and distinguished from the coupled mode tip fields. Built upon SIF-based fracture criteria for quasi Mode I and Mode II, the stress intensity factor（SIF）-based fracture criterion for mixed mode interface cracks is proposed and validated against existing experimental results.

关键词： Interface crack Stress singularity Fracture criterion Stress intensity factor

Efficacy and safety of Tuomin Zhiti decoction(脱敏止嚏汤) on patients with seasonal allergic rhinitis: A randomized， double-blind， placebo-controlled trial

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Journal of Traditional Chinese Medicine 2025年

作者： ZHAO Weibo WANG Yaqi KONG Lingyao WANG Tianyi ZHAO Haihong ZHANG Ying LUO Bin WANG ji WANG Qi National Institute of TCM Constitution and Preventive Medicine， Beijing University of Chinese Medicine College of Basic Medical Sciences， Zhejiang Chinese Medical University Centre for Evidence-Based Chinese Medicine， Beijing University of Chinese Medicine Beijing University of Chinese Medicine International School

Objective: To evaluate the clinical efficacy and safety of Tuomin Zhiti decoction (TZD) in the short-term treatment of seasonal allergic rhinitis (SAR). Methods: This study is a randomized， double-blind placebo-controlled， and single-center clinical trial. In April 2021， during the spring pollen season in Beijing， 94 SAR patients aged 19-60 years were randomized (1:1 ratio) to receive two weeks of TZD or placebo. The primary outcome was the change of Total Nasal Symptom Score (TNSS) and Total Ocular Symptom Score (TOSS) from baseline to the end of treatment. Secondary outcomes were the changed score of the mini Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ)， Rescue Medication Score (RMS)， and Patient Global Impression of Change (PGIC). All adverse events were recorded and evaluated by two senior physicians. Results: TZD significantly reduced both the total nasal symptom scores and total ocular symptom scores compared to scores at baseline， while the placebo group showed an increasing trajectory in both symptom scores. Compared to the placebo group， the TZD group also showed a greater improvement in the quality of life， scores of RMS， nasal and eye symptoms scores after TZD treatment (P < 0.001). Most notably， at the end of treatment， the proportion of remission measured by PGIC was significantly higher in the TZD group (82.97%) compared with the placebo group (47.72%， P < 0.001). Conclusion: This study suggested that two weeks of TZD is an effective and safe treatment for SAR patients and spring pollen allergy， TZD could significantly improve the nasal and eye symptoms and improve the quality of life of patients.

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OBTAINING PRECISE CRITICAL DRAW RATIO OF DRAW RESONANCE IN MELT SPINING BY NUMERICAL SIMULATION OF DIFFERENCE EQUATIONS

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Chinese Journal of Polymer Science 2005年第3期23卷 311-318页

作者： ji-nanCao IndustrialResearchInstituteSwinburne SwinburneUniversityofTechnologyP.O.Box218HawthornVictoria3122Australia

Direct difference methods have been used to solve the simultaneous non-linear partial differential equations formelt spinning without recourse to linearisation or perturbation *** stability of each difference schemes wasstudied by error analysis using the Taylor series,and by comparison of the results obtained from numerical simulation withthe logical value in melt *** is found that computation with 19 digit long double precision has significantlysimplified the stability problem of difference *** this method,the precise critical draw ratio of draw resonancein an isothermal and uniform tension spinning of Newtonian fluids can be obtained in between 20.218 and 21.219,a figureconsistent with 20.218 which was obtained by a linear perturbation approximation method by Kase and *** thus haspaved the way to computation of full information for unsteady melt spinning processes using the difference method.

关键词： Draw resonance Melt spinning Newtonian fluid Numerical simulation.

人工智能信息技术在中医四诊现代化研究中的应用现状与展望

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上海中医药杂志 2025年第1期59卷 7-12页

作者：崔骥许家佗上海中医药大学中医学院上海201203

随着人工智能信息技术爆发式发展,其在中医领域的应用也逐渐普及。随着现代信息技术的发展,中医诊断学中的望、闻、问、切四诊技术逐渐客观化、标准化、信息化与智能化。借助人工智能、大数据、智能医疗器械等关键要素,提升中医四诊融... 详细信息

随着人工智能信息技术爆发式发展,其在中医领域的应用也逐渐普及。随着现代信息技术的发展,中医诊断学中的望、闻、问、切四诊技术逐渐客观化、标准化、信息化与智能化。借助人工智能、大数据、智能医疗器械等关键要素,提升中医四诊融合及诊断水平,并为中医学的发展注入新的活力,是中医诊断学尤其是四诊技术发展的必然趋势。梳理了近年来中医望诊、闻诊、问诊和切诊的智能化发展及四诊融合概况,以期为中医诊断学及中医现代化的发展提供必要的信息化与智能化发展思路。

关键词：中医诊断四诊融合人工智能中医现代化研究进展

Surface micro-arrays enhancing electromagnetic interference shielding of polydimethylsiloxane/multiwalled carbon nanotubes nanocomposites

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Nano Research 2025年第1期18卷 508-519页

作者： Ke jiang Zhi Chen ji Yu Chen Zheng Shan Huang Ming Wang Chongqing Key Laboratory of Soft-Matter Material Manufacturing School of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China School of Mechanics Civil Engineering and ArchitecturesNorthwestern Polytechnical UniversityXi’an 710072China jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Herein,the electromagnetic shielding performance of surface concave-convex(SC)and zig-zag micro-arrays was studied by using a simulation prediction and a three-dimensional(3D)printing custom ***,surface stripe concaveconvex(SSC)and surface cylindrical concave-convex(SCC)micro-arrays with or without zig-zag micro-arrays are designed,and their shielding performance is simulated in multi-bands(C-,X-band).The multiwalled carbon nanotubes/polydimethylsiloxane composites(MWCNT/PDMS)with different SC structures and different electrical conductivity are molded in acrylonitrile-butadiene-styrene copolymer(ABS)molds which are printed by a 3D *** results show that the electromagnetic interference shielding effectiveness(EMI SE)of the samples can be enhanced by constructing the SC micro-arrays with zig-zag micro-arrays,and improving with the increase of conductivity and *** addition,the shielding mechanism of the SC-MWCNT/PDMS composites is investigated and discussed by an electromagnetic simulation.

关键词： surface micro-arrays electrical properties electromagnetic interference(EMI)shielding three-dimensional(3D)printing

Modified Ringel-Hall algebras,naive lattice algebras and lattice algebras

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Science China Mathematics 2020年第4期63卷 671-688页

作者： ji Lin Department of Mathematics Sichuan UniversityChengdu 610064China School of Mathematics and Statistics Fuyang Normal UniversityFuyang 236037China

For a given hereditary abelian category satisfying some finiteness conditions,in certain twisted cases it is shown that the modified Ringel-Hall algebra is isomorphic to the naive lattice algebra and there exists an epimorphism from the modified Ringel-Hall algebra to the lattice ***,the kernel of this epimorphism is described ***,we show that the naive lattice algebra is invariant under the derived equivalences of hereditary abelian categories.

关键词： modified Ringel-Hall algebras naive lattice algebras lattice algebras hereditary abelian categories