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关键词： 红外光谱技术   纺织品   检测   物质测量  

摘要： 文章旨在探讨红外光谱技术在纺织品检测领域的具体应用。研究首先对红外光谱技术的非破坏性、快速分析和高灵敏度等应用优势进行了详尽分析,并进一步探讨了该技术在纤维组成与含量分析、纺织品染料与助剂检测、表面处理剂检测以及纤维取向度与结晶度测定等方面的运用途径,以期推动纺织行业更加稳定健康的发展。

关键词： Atherosclerosis   Premature coronary artery disease   Risk factors   Severity   Prevalence  

摘要： AbstractIntroductionThe present study aims to compare the risk factors, clinical presentation, and severity of coronary artery involvement in young compared to elderly CAD patients to assess the cardiovascular health status for better disease management and control of these specific patients. MethodsThis registry-based cross-sectional study was conducted using Coronary Angiography and Angioplasty Registry (CAAR) patients in east of Tehran, Iran. The data were extracted from 330 patients with confirmed CAD recorded by the CAAR during July 2021 to August 2023. ResultsThe majority of patients in MCAD (68.2%) and VECAD (80%) were male, while the majority of PCAD patients were female (51.8%). Among PCAD patients, the prevalence of diabetes (38.1%) was higher than in other groups. The presence of IHD history in the father (38.1%) and mother (26.3%) was higher in the VECAD group. The mean total cholesterol, LDL, and LDL/HDL ratio were higher in the VECAD group. Among MCAD group (75.4%) compared to PCAD (58.1%) and VECAD (47.2%) groups, the multi-vessel disease was more *** patients had the highest median Gensini score compared to PCAD and VECAD patients. Also, in male compared to female the mean Gensini score was higher by 8 units (ß = 8.26, 95%CI = 0.24, 16.28). ConclusionModifiable risk factors in young CAD patients are common. High LDL-C levels and smoking were the common modifiable CVD risk factors in young patients, indicating the significant role of these traditional risk factors in early atherosclerosis development alongside inheritable risk-factors such as positive family history that were more common in young CAD patients. While, the severity of coronary artery involvement in individuals with MCAD was higher, but the priority of involvement based on the type of vessel was almost the same in all CAD groups.

关键词： 柴油机   配气凸轮   型线设计  

摘要： 在柴油机性能改造过程中,通过原机配气结构参数建立GT-Vtrain配气机构模型。在模型中输入原机的凸轮型线,计算得到原机配气凸轮的最大正向加速度、最大负向加速度、最大加速度导数以及缓冲段最大速度,以此作为改型配气凸轮的动力学性能约束条件。根据柴油机性能改造要求的配气相位,计算得到改型凸轮型线数据。经输入配气机构模型验证,改型凸轮的缓冲段最大速度、最大正负加速度、最大加速度导数等参数均不超过原机,未出现反跳、接触应力过大、气门飞脱等现象,可确定改型凸轮型线满足设计要求。

关键词： 中职院校   岗课赛证”融通   机械制图与CAD   改革策略  

摘要： “岗课赛证”融通综合育人模式契合职业教育特点和现代教学规律,有利于充分发挥职业院校在专业技术人才培养方面的特色优势,有助于实现教师、学生和课程三方面的有机结合,提升职业人才培养质量。文章以“岗课赛证”融通背景下“机械制图与CAD”教学改革为研究主题,首先阐述了“岗课赛证”融通的概念,然后分析了“岗课赛证”融通背景下中职“机械制图与CAD”课程教学现存的问题,最后探索出了明确技能要求、重构教学内容、创新教学手段、革新教学评价等改革策略,以期为相关工作人员提供参考。

关键词： 隧道   盾构掘进响应   下负荷面本构模型   应力渗流耦合计算  

摘要： [目的]盾构在富水软弱地层中施工时,地层变形往往会受土体强度、变形及渗透特性的共同影响,其中渗透特性导致的时间效应会进一步影响周围环境。因此,有必要采用合理的本构模型开展应力渗流耦合计算,研究饱和粉质黏土中盾构掘进诱发的地层变形响应。[方法]以苏州轨道交通11号线鱼池泾站—白河潭站区间为例,采用能够反映土体力学特性状态相关性的下负荷面本构模型,并结合应力渗流耦合有限元程序,计算分析饱和粉质黏土中盾构掘进引起的地面沉降及孔隙水压力响应规律,并与工程实测数据进行对比。[结果及结论]基于下负荷面本构模型的应力渗流耦合计算能够较好地再现盾构掘进影响效应;饱和粉质黏土地层中的盾构掘进容易诱发地层变形,且掌子面压力的变化对地层变形有显著影响,掌子面压力过大往往会诱发地面隆起;盾构施工会对掘进面前方土体产生挤压扰动,继而诱发周围土层中超孔隙水压力演化,这也是地层变形时间效应的内在机制。

关键词： 织机   引纬机构   纬纱张力   超宽超厚织物   剑杆托举  

摘要： 为了解决传统织机引纬系统在处理超宽超厚织物时难以连续精确稳定地进行大跨距、多层引纬的问题,设计了一种超宽超厚三维平板织机引纬系统。该引纬系统由引纬机构、剑杆托举机构及纬纱张力机构构成。首先介绍了引纬系统的工作原理与各主要机构功能,其次对剑杆选取机构中的剑杆材料进行选择,对强度进行校核,确保剑杆在大跨度引纬时具有较小的抖动量及下垂量,从而保证大跨度引纬的稳定性。试验结果表明,该引纬系统能够有效提高织机的工作效率和生产质量,可满足超宽超厚织物连续大跨度引纬织造的需求,极大提高了超宽超厚三维织物的生产效率。

关键词： 专业课   增值性评价   评价体系   知识图谱   数字技术   实践研究  

摘要： 2022年,教育部颁布了《义务教育课程方案和课程标准》,在《深化新时代教育评价改革总体方案》提出要探索增值评价之后,再次提出“要改进教育评价,关注学生真实发生的进步,积极探索增值评价”[1]。改善传统教育评价体系、探索增值评价是势在必行的。该文主要针对专业课课堂教学的增值性评价展开实践研究。

关键词： 凸轮构件   多自由度摆动辗压成形   两步成形   预成形   终成形  

摘要： 针对凸轮构件的外轮廊线复杂,难以通过塑性成形加工的问题,根据其几何结构特点,提出采用两步多自由度摆动辗压成形工艺制造凸轮构件。设计了凸轮构件多自由度摆动辗压的预成形和终成形模具,并建立了预成形和终成形有限元模型,通过有限元模拟揭示了金属流动、等效应变以及成形载荷演变规律。进行了凸轮构件多自由度摆动辗压的预成形和终成形工艺实验,结果表明,工艺实验结果与有限元模拟保持一致,这表明通过两步多自由度摆动辗压成形工艺制造凸轮构件是可行的。

关键词： Architectural heritage   Lighting simulation   Point clouds   Photogrammetry   CAD  

摘要： Computer simulation of the incidence of natural light in heritage buildings has entailed a very fruitful field of experimentation within Digital Art History in recent years, although little has been discussed about its validity. This article seeks to demonstrate that although the accuracy of the results decreases when simulating the incidence of natural light of a heritage interior on a point cloud compared to a CAD, the margin of error can be accepted in historical studies. To carry out this test, the church of the Dominican convent of San Jacinto in Seville (Spain) has been used as a model. This interior has been analyzed with RELux and DIALux starting from a CAD and photogrammetry without simplifying it or cleaning it. With these examples, it can be concluded that these tools become useful for the study of historical buildings, despite their limitations.