中医药治疗动脉粥样硬化研究进展可视化分析

目的:探讨中医药治疗动脉粥样硬化(AS)的研究现状与趋势,为今后中医药防治AS的研究提供参考。方法:使用Citespace软件对中国知网(CNKI)和Web of Science(WOS)核心数据库中1999年1月1日—2023年12月31日期间关于中医药治疗AS的相关文献进行图谱绘制和分析。结果:CNKI数据库纳入文献4183篇,WOS核心数据库纳入文献1040篇。中、英文文献发文量最多的作者分别是杨关林和ZHANGLei、发文量最多的机构分别是辽宁中医药大学和中国中医科学院;研究主要集中在中医证型、临床研究、作用机制研究,近期研究热点在肠道菌群、炎症反应、巨噬细胞。结论:中医药治疗AS机制研究发展迅速,但临床研究方面仍缺少高质量临床试验研究。

Safety of the express freight train running over a long-span bridge

Purpose-Express freight transportation is in rapid development currently.Owing to the higher speed of express freight train,the deformation of the bridge deck worsens the railway line condition under the action of wind and train moving load when the train runs over a long-span bridge.Besides,the blunt car body of vehicle has poor aerodynamic characteristics,bringing a greater challenge on the running stability in the crosswind.Design/methodology/approach-In this study,the aerodynamic force coefficients of express freight vehicles on the bridge are measured by scale model wind tunnel test.The dynamic model of the train-long-span steel truss bridge coupling system is established,and the dynamic response as well as the running safety of vehicle are evaluated.Findings-The results show that wind speed has a significant influence on running safety,which is mainly reflected in the over-limitation of wheel unloading rate.The wind speed limit decreases with train speed,and it reduces to 18.83 m/s when the train speed is 160 km/h.Originality/value-This study deepens the theoretical understanding of the interaction between vehicles and bridges and proposes new methods for analyzing similar engineering problems.It also provides a new theoretical basis for the safety assessment of express freight trains.

The heterogeneous impact of China-Europe railway express on the efficiency of logistics industry in node cities

Purpose-The spatiotemporal compression effect of China-Europe Railway Express(CR-Express)can reduce the filow costs of resources between China's node cities.Additionally,it can break through the limitations of low-added-value marine products,significantly impacting the logistics industry efficiency.However,there are few literature verifying and analyzing its heterogeneity.This study explores the impact of CR-Express on the efficiency of logistics industry in node cities and analyzes the heterogeneity.Design/methodology/approach-First,this study uses panel data to measure the efficiency of node city logistics industry.Secondiy,this study discusses the impact of the opening of CR-Express on the efficiency of logistics industry in node cities based on the multi-period differential model.Finally,according to the node city difference,the sample city experimental group is grouped for heterogeneity analysis.Findings-The results show that CR-Express can promote the urban logistics industry efficiency,with an average effect of 4.55%.According to the urban characteristics classification,the heterogeneity analysis shows that the efficiency improvement effect of logistics industry in inland cities is more obvious.The improvement effect of node cities and central cities in central and western China is stronger,especially in the sample of megacities and type I big cities.Compared with non-value chain industrial products,the CR-Express has significant promotion effects on the logistics efficiency of the cities where main goods are value chain products.Originality/value-Under the background of double cycle development,this paper can provide a scientific basis for the investment benefit evaluation of CR-Express construction and the follow-up route planning.

Risk assessment of high-speed railway CTC system based on improved game theory and cloud model

Purpose-In order to solve the problem of inaccurate calculation of index weights,subjectivity and uncertainty of index assessment in the risk assessment process,this study aims to propose a scientific and reasonable centralized traffic control(CTC)system risk assessment method.Design/methodologylapproach-First,system-theoretic process analysis(STPA)is used to conduct risk analysis on the CTC system and constructs risk assessment indexes based on this analysis.Then,to enhance the accuracy of weight calculation,the fuzzy analytical hierarchy process(FAHP),fuzzy decision-making trial and evaluation laboratory(FDEMATEL)and entropy weight method are employed to calculate the subjective weight,relative weight and objective weight of each index.These three types of weights are combined using game theory to obtain the combined weight for each index.To reduce subjectivity and uncertainty in the assessment process,the backward cloud generator method is utilized to obtain the numerical character(NC)of the cloud model for each index.The NCs of the indexes are then weighted to derive the comprehensive cloud for risk assessment of the CTC system.This cloud model is used to obtain the CTC system's comprehensive risk assessment.The model's similarity measurement method gauges the likeness between the comprehensive risk assessment cloud and the risk standard cloud.Finally,this process yields the risk assessment results for the CTC system.Findings-The cloud model can handle the subjectivity and fuzziness in the risk assessment process well.The cloud model-based risk assessment method was applied to the CTC system risk assessment of a railway group and achieved good results.Originality/value-This study provides a cloud model-based method for risk assessment of CTC systems,which accurately calculates the weight of risk indexes and uses cloud models to reduce uncertainty and subjectivity in the assessment,achieving effective risk assessment of CTC systems.It can provide a reference and theoretical basis for risk management of the CTC system.

Eddy current quantitative evaluation of high-speed railway contact wire cracks based on neural network

Purpose–The purpose of this study is to study the quantitative evaluation method of contact wire cracks by analyzing the changing law of eddy current signal characteristics under different cracks of contact wire of high-speed railway so as to provide a new way of thinking and method for the detection of contact wire injuries of high-speed railway.Design/methodology/approach–Based on the principle of eddy current detection and the specification parameters of high-speed railway contact wires in China,a finite element model for eddy current testing of contact wires was established to explore the variation patterns of crack signal characteristics in numerical simulation.A crack detection system based on eddy current detection was built,and eddy current detection voltage data was obtained for cracks of different depths and widths.By analyzing the variation law of eddy current signals,characteristic parameters were obtained and a quantitative evaluation model for crack width and depth was established based on the back propagation(BP)neural network.Findings–Numerical simulation and experimental detection of eddy current signal change rule is basically consistent,based on the law of the selected characteristics of the parameters in the BP neural network crack quantitative evaluation model also has a certain degree of effectiveness and reliability.BP neural network training results show that the classification accuracy for different widths and depths of the classification is 100 and 85.71%,respectively,and can be effectively realized on the high-speed railway contact line cracks of the quantitative evaluation classification.Originality/value–This study establishes a new type of high-speed railway contact wire crack detection and identification method,which provides a new technical means for high-speed railway contact wire injury detection.The study of eddy current characteristic law and quantitative evaluation model for different cracks in contact line has important academic value and practical significance,and it has certain guiding significance for the detection technology of contact line in high-speed railway.

Study on the pattern of train arrival headway time in high-speed railway

Purpose-The design goal for the tracking interval of high-speed railway trains in China is 3 min,but it is difficult to achieve,and it is widely believed that it is mainly limited by the tracking interval of train arrivals.If the train arrival tracking interval can be compressed,it will be beneficial for China's high-speed railway to achieve a 3-min train tracking interval.The goal of this article is to study how to compress the train arrival tracking interval.Design/methodologylapproach-By simulating the process of dense train groups arriving at the station and stopping,the headway between train arrivals at the station was calculated,and the pattern of train arrival headway was obtained,changing the traditional understanding that the train arrival headway is considered the main factor limiting the headway of trains.Findings-When the running speed of trains is high,the headway between trains is short,the length of the station approach throat area is considerable and frequent train arrivals at the station,the arrival headway for the first group or several groups of trains will exceed the headway,but the subsequent sets of trains will havea headway equal to the arrival headway.This convergence characteristic is obtained by appropriately increasing the running time.Originality/value-According to this pattern,there is no need to overly emphasize the impact of train arrival headway on the headway.This plays an important role in compressing train headway and improving high-speedrailwaycapacity.

Optimization study of station track utilization in high-speed railroad based on constraints of control in random origin and process

Purpose-The purpose of this paper is to eliminate the fluctuations in train arrival and departure times caused by skewed distributions in interval operation times.These fluctuations arise from random origin and process factors during interval operations and can accumulate over multiple intervals.The aim is to enhance the robustness of high-speed rail station arrival and departure track utilization schemes.Design/methodologylapproach-To achieve this objective,the paper simulates actual train operations,incorporating the fluctuations in interval operation times into the utilization of arrival and departure tracks at the station.The Monte Carlo simulation method is adopted to solve this problem.This approach transforms a nonlinear model,which includes constraints from probability distribution functions and is difficult to solve directly,into a linear programming model that is easier to handle.The method then linearly weights two objectives to optimize the solution.Findings-Through the application of Monte Carlo simulation,the study successfully converts the complex nonlinear model with probability distribution function constraints into a manageable linear programming model.By continuously adjusting the weighting coefficients of the linear objectives,the method is able to optimize the Pareto solution.Notably,this approach does not require extensive scene data to obtain a satisfactory Pareto solution set.Originality/value-The paper contributes to the field by introducing a novel method for optimizing high-speed rail station arrival and departure track utilization in the presence of fluctuations in interval operation times.The use of Monte Carlo simulation to transform the problem into a tractable linear programming model represents a significant advancement.Furthermore,the method's ability to produce satisfactory Pareto solutions without relying on extensive data sets adds to its practical value and applicability in real-world scenarios.

基于模糊PID的多纸种造纸机定量控制方法研究

多纸张造纸机系统会受到非线性以及时变的影响。为了提高定量控制精度,提出基于模糊PID的多纸种造纸机定量控制方法研究,提取出定量回路动态特性,得出影响多纸种造纸机定量的因素;对PID控制器规则进行分析,得出控制参数对多纸种造纸机定量控制结果的影响,并针对分析结果提出内模控制方法对PID控制器参数进行确定,消除时变的影响且降低控制过程中的超调量;最终,为消除非线性干扰,基于模糊PID控制方法对多纸种造纸机定量影响因素进行调整,输出对应的控制量,实现多纸种造纸机定量控制。实验结果表明,所提方法的定量控制效果佳、超调量较低以及控制器参数优化及时。

单篇学术论文创新类型研究

[目的/意义]学术论文创新类型研究是剖析学术论文创新性的前提,是内容文本层面进行学术论文创新性识别与测度的基础。[方法/过程]在对学术论文的概念和属性阐释的基础上,基于文献调研法,进行总结归纳,从创新程度、研究内容、文献结构、重要表征形式4个角度对单篇学术论文创新类型进行划分,并从三维时间视角对单篇学术论文创新类型的作用过程进行系统探讨。[结果/结论]经过分类,最终得到3种创新程度(颠覆性、独创性、渐进性)、8种研究内容(理论、观点、主题、问题或对象、方法、数据、结论或事实、应用)、4种文献结构(基础描述、技术方法、结果结论、未来展望)以及2种重要表征形式(单要素、组合要素)的创新类型划分结果,进而提出创新类型研究对学术论文创新性评价的启示与应用价值。

自动换卷机构的纸带拼接刚柔耦合分析与试验研究

针对卷烟纸带拼接中压模纹理与拼接力设计不当,易发生纸带拼接松脱、错位和穿透的问题,基于自动换卷机构的纸带拼接原理,建立自动换卷机构刚柔耦合模型,采用数值模拟与试验测试方法,研究对辊材料、拼接力和压模纹理对纸带拼接效果的影响规律。结果表明,4种对辊材料(橡胶、尼龙、铝、钢)的纸带拼接力仿真值分别为177.1,3.50×104,1.29×106,4.45×106 MPa,仿真结果与理论值相符。设计不同压模纹理的纸带拼接试验,测算出菱形压模拼接后的纸带断裂应力为1.040 MPa,弹性模量为17.816 MPa;矩形压模拼接后的纸带断裂应力为1.802 MPa,弹性模量为28.001 MPa,菱形压模拼接质量优于矩形压模。研究为自动换卷机构的对辊材料和压模纹理设计,以及纸带拼接效果评价提供技术支撑。

烟盒包装用纸性能分析及其专用检测方法研究

目的建立烟盒包装用纸相关性能的专用检测方法,为其具体应用提供理论依据。方法采用相应的国家标准及研究方法对烟盒样品的定量、挺度和耐折度进行测定,分析不同样品的纤维种类、组成和表面润湿性能。结果不同研究方法测得的物理指标与标准方法的相比有一定的差异,但它们之间满足一定的数学函数关系;烟盒包装用纸中主要含有针叶木化学浆(10%~41%)和阔叶木化学浆(21%~90%);纸样和水界面的接触角较高(70.74°~72.76°),表明其对水的润湿性较差,有利于保证其上机适应性和产品质量;二碘甲烷和纸样界面的接触角相对较低(41.72°~50.44°),表明样品对有机物具有一定的亲和性;表面能分布范围为42~46 mN/m,其值越低,越有利于样品对油墨的附着。结论建立了烟盒包装用纸定量、挺度和耐折度的专用检测方法,对烟盒样品的纤维种类、组成和表面润湿性能进行了分析,具有一定的实际应用价值。

环保纸袋制袋技术与装备研究进展

目的研究目前纸袋生产装备自动化和现代化的发展水平,开展调查研究与分析。方法综述国内外环保纸袋自动化生产技术和装备的研究现状及发展动态,分析总结国内外具有代表性的环保纸袋生产设备结构和类型,阐述各类制袋技术与机构的工作原理和结构特征。结果目前国内纸袋制袋机高柔性化、高速化、智能化存在不足。结论高效率、高精度、高柔性的数字化生产是今后环保纸袋制袋技术发展的重要方向,应加强国内印刷包装设备的自动化、智能化、信息化水平。

浅谈干式纸盒喷漆室设计说明

主要介绍了干式喷漆室的设计思路及适用范围,系统由擦净间、喷涂区、晾干间、洁净间、风淋室组成,喷涂段包含动压室、静压室、操作间、干式抽屉式纸盒过滤器漆雾捕集装置。

女装褶饰袖结构设计及其技术原理

褶饰袖是将褶饰与衣袖相结合的一种创新袖型,但立体裁剪较难实现复杂的褶饰袖,针对这一问题,文章介绍了褶饰袖分类及其造型形态与结构,在东华女装袖原型的基础上,通过平面结构设计及立体试样的方式,根据褶饰袖款式设计,运用平行、扇形、混合切展的方式来确定褶量,完成女装褶饰袖结构设计及样板制作。针对各类型复杂褶饰袖结构设计技术,总结褶饰袖结构设计技术原理与规则,有原型法、平行切展法、结构重点法、主褶饰线确定法、褶饰线类比及仿形法、闭合法、旋转扇形切展法、纸样折叠验证法、混合切展法、褶饰直接作图法、检验法、多种切展法等,这些规则可以举一反三灵活运用在复杂女装褶饰结构设计中,为服装专业人员进行褶饰结构设计及制版提供参考。

YF716型包装机物料站自动拼接机构的研制及应用

为提升包装机物料站拼接机构的自动化程度,基于物料的输送速度和拼接方式,通过集成创新的方法设计了新型包装机物料站自动拼接机构。该机构主要由剪切拼接装置、胶带自动供给装置和导纸压紧装置组成。将YF716型物料站与ZB48A型包装机组对接,分别全自动供应铝箔纸、内框纸和小盒透明纸,包装机以800包/min的速度运行,记录3个月内物料站的故障次数及停机时间,结果显示自动拼接机构运行平稳,新旧纸带拼接后切口平齐,纵向无间隙,轴向无错位;因物料站故障导致包装机停机10次,每次停机不超过5 min,平均有效运行率99%,运行稳定,自动化程度高,结构简单可靠。

封端型水性聚氨酯固化剂的合成及应用

封端型水性聚氨酯固化剂是现阶段汽车工业的重要研究内容,其在汽车滤纸中的应用,能够有效提高滤纸的硬挺度和耐水性。基于此,文章研究了以甲苯二异氰酸酯、聚丙二醇作为反应原料,NaHSO_(3)作为封端剂,结合乳化剂的使用所制备成的新型封端型水性聚氨酯固化剂,凭借其简单的合成方法和低成本优势,提高滤纸品质。

特高压直流套管用环氧树脂/皱纹纸复合绝缘体系介电性能的研究

特高压直流套管是制约我国特高压直流输电设备发展的瓶颈。针对特高压直流套管用绝缘材料,分析观察了直流套管用皱纹纸的显微结构,制备了纯环氧树脂和环氧树脂/皱纹纸复合绝缘体系的试样,进行了介电性能测试,研究了不同试样介电性能随温度的变化规律。为研制特高压直流干式套管提供试验依据。

一种新型短切碳纤维增强纸基摩擦材料研究

以短切碳纤维为增强纤维 ,采用湿法工艺研制成功一种新型无石棉纸基摩擦材料 ,采用TG DTA热分析方法、定速摩擦试验和惯量摩擦研究了摩擦材料耐热性能、摩擦性能和磨损性能。试验结果表明 ,新研制的炭纤维增强纸基摩擦材料的起始分解温度和失重速率等耐热性能指标优良 ,动摩擦系数高达 0 .136～ 0 .14 9,且摩擦系数稳定 ,磨损率低 ,是一种理想的新型无石棉纸基摩擦材料。

无创调节式夹板托支架治疗桡骨远端骨折的临床研究

目的对比分析无创调节式夹板托支架与塑性铅丝纸质夹板治疗桡骨远端骨折,对局部解剖结构及腕关节功能的影响。方法 2012年1月至2012年12月我科收治40例桡骨远端骨折患者,随机分为塑性铅丝纸质夹板治疗组、无创调节式夹板托支架治疗组,每组各20例,在闭合手法整复的基础上分别采用塑性铝丝纸质夹板、无创调节式夹板托支架固定。结果所有患者均获得随访,骨折均愈合,无并发症;经统计学分析,2组在恢复桡骨远端解剖结构及维持掌倾角、尺偏角方面无差异(P>0.05),但无创调节式夹板托支架组在桡骨高度维持及腕关节功能恢复方面优于塑性铅丝纸质夹板组(P<0.05)。结论无创调节式夹板托支架治疗桡骨远端骨折能有效恢复并维持桡骨远端解剖结构,避免桡骨短缩畸形,腕关节功能恢复满意,获得良好疗效。

我们需要什么样的实证研究:类型与应用模式——以《现代远程教育研究》2010-2017年195篇实证研究论文为例

实证研究由于倡导"用数据资料说话",备受研究者、管理者和决策者的重视。学术期刊是承载教育实证研究成果的重要载体。从期刊编辑的角度来审视教育实证研究的类型和特征,有助于提升教育实证研究论文的写作和分析规范。《现代远程教育研究》作为远程教育和教育技术领域中学术影响力较高的期刊,2010-2017年共刊发了195篇实证研究论文。对这些论文从方法论角度进行系统描述、分类和分析发现,我国远程教育实证研究论文在数量上体现出增长的趋势,不仅写作形式上更加规范,而且内容质量也愈加厚实。总体上我国远程教育实证研究论文可以归纳为文献研究、建构研究、案例研究、实验研究、调查研究、文本研究和关系研究七类,每一种类型的实证研究论文都体现出各自的方法论意蕴,以及不同的研究流程和分析模式。建构研究尤其是模式建构研究是我国远程教育和教育技术领域实证研究的重要特色。随着技术的快速发展和跨学科研究趋势的日益影响,文献研究、精细化实验研究、文本研究和关系研究将会体现出更多的技术支持特色。