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关键词： 竹浆纤维   机织物   喷气涡流纺   包芯纱   灰色关联度分析   服用性能  

摘要： 为了探讨竹浆纤维喷气涡流纺包芯纱在夏季用机织物中的适用性,以竹浆纤维喷气涡流纺包芯纱为原料,通过设计不同纱线类型、芯丝成分与织物组织的多组竹浆纤维夏季用机织物,测试其保形性、透通性及接触凉感等服用性能指标,并基于测试数据运用灰色关联度分析法进行综合评价。结果表明,纺纱方式和芯丝选择、织物组织对竹浆纤维织物的保形性和透通性等服用性能有着不同程度的影响,喷气涡流纺包芯纱独特的成纱机制有效提升了织物的抗弯刚度和抗皱性,吸湿排汗涤纶芯丝则通过毛细效应改善了织物的吸湿快干性能;竹浆纤维喷气涡流纺包芯纱机织物在抗皱性、透气性和透湿性等服用性能方面表现良好,具有一定的接触凉感,适用于夏季衬衫、裙装及家纺产品开发,为竹浆纤维织物的设计与应用提供了理论依据和实践参考。

关键词： 负离子涤纶   粘胶   喷毛带子纱   模糊综合评价   针织物  

摘要： 为了探究负离子涤纶粘胶喷毛带子纱针织物的性能,对5种不同组织(纬平针组织、2+2罗纹组织、四平组织、双反面组织、半畦编组织)的负离子涤纶/粘胶喷毛带子纱针织物的性能进行测试与分析。结果表明:织物的性能受织物组织、线圈密度、单位面积质量和厚度的综合影响较大。采用主观赋权法对各组织针织物的性能进行模糊综合评价,计算得出的综合评分从高到低依次为2+2罗纹组织针织物、四平组织针织物、双反面组织针织物、纬平针组织针织物和半畦编组织针织物。其中,2+2罗纹组织针织物的综合性能最好,其负离子发生量高达2769个/cm3,具有高效负离子释放性能的同时还有优异的服用舒适性,该组织适于开发负离子纺织品;半畦编组织针织物的综合性能最差,纬平针组织针织物与之相近,不宜开发为负离子纺织品。

关键词： 残膜回收   凸轮驱动   捡拾分离装置   参数优化  

摘要： 针对目前我国农田用残膜捡拾机理分析不完善、机具作业效率低、含杂率高的问题,设计了一种凸轮滚筒式农田残膜回收机。通过凸轮机构驱动捡拾齿的伸出和回缩完成对农田残膜的捡拾和分离,提高农田残膜回收的作业效率;通过对捡拾齿运动轨迹分析设计了凸轮的轮廓曲线,并对农田残膜捡拾过程进行力学分析,得到土壤对膜土混杂物的粘性力和凸轮滚筒转速是影响粘性力的重要因素;对拾膜过程进行运动学分析,得到凸轮滚筒的回转半径值和滚筒转速是影响机具性能的关键因素;对拾膜过程建立笛卡尔坐标系进行分析,优化了机具作业参数。以残膜回收机前进速度、凸轮滚筒转速、凸轮回转半径为试验因素,以农田残膜捡拾率和含杂率为试验指标进行田间响应面试验和参数优化验证试验,得到最佳作业性能下的参数为残膜回收机前进速度5.7 km/h、凸轮滚筒转速698 r/min、凸轮基圆直径718 mm,此时农田残膜捡拾率为88.2%、含杂率为32.6%,满足农田残膜回收要求。

关键词： Hip   Adolescent hip dysplasia   Cam morphology   FAI   MRI  

摘要： Hip dysplasia and cam morphology are both common causes of hip pain in pediatric patients. However, there is limited literature on how the presence of hip dysplasia may affect the prevalence of cam morphology.

关键词： laser point cloud   lift evaluation   geometric optics   circle fitting   profile fitting  

摘要： Aiming at the need for rapid cam lift error detection, a vision-based measurement method for cam lift errors using laser point cloud data is proposed. Specifically, a laser scanner is first used to acquire the 3D point cloud model of the target cam component, which is then preprocessed. Subsequently, the point cloud slicing algorithm termed the Circular Method of Rotary Cutting (CMRC) is applied to extract point cloud slices of the cam. For each extracted slice, this study proposes a Hyper-IRLS-Tukey method to determine the center of the base circle. This circle fitting approach can effectively resist noise interference during the fitting process, thereby significantly improving the accuracy of the fitted base circle center. Meanwhile, to obtain an accurate and smooth profile curve, an adaptive locally weighted spline interpolation (ALWSI) method is introduced to perform profile fitting on the cam contour points of each slice. This method can filter out highly deviated contour points during the profile fitting process. Based on the fitted profile curve, the cam lift is evaluated and the lift error is further detected. Experimental results show that the proposed circle fitting method achieves higher accuracy and stability compared with LSC, Taubin, and Hyper methods. Comparisons with measurements from a coordinate measuring machine (CMM) indicate that the mean maximum absolute error of the proposed method does not exceed 4.4 mu m. In contrast to other methods, the maximum mean absolute error of the ALWSI method remains within 5.8 mu m. The largest difference in mean absolute error relative to the CMM results is within 4.7 mu m, demonstrating that the method satisfies the practical requirements for rapid and efficient measurement of cam lift errors. Finally, the uncertainty of the detection results is calculated to further verify the feasibility and accuracy of the proposed approach.

关键词： 2D-to-BIM conversion   BIM object generation   CAD material layer annotation   Semantic enrichment  

摘要： This study proposes a method for semantically enriching a building information model (BIM) by converting and supplementing material layer information in computer-aided-design (CAD) drawings into semantically rich BIM objects. Despite the widespread adoption of BIMs, practices relying on CAD drawings are still prevalent and fully automated conversion from CAD-to-BIM remains challenging. Previous studies on automatically converting 2D drawings into a BIM have primarily focused on geometric reconstruction, often overlooking textual data such as material layer annotations, which contain essential BIM object details. However, the recognition and conversion of material layer annotations to BIM objects pose several challenges, including inconsistent annotation formats, vague associations between annotations and objects, and missing material function and property information. To address these challenges, this paper introduces a four-step method: (1) semantic clustering of material layer annotations into groups corresponding to individual objects; (2) material layer function assignment using a newly proposed mistake-driven prompting technique, which incorporates feedback from common mistaken cases; (3) object type classification using a large language model based solely on material layer texts; and (4) automated generation of BIM objects semantically enriched with material property information in single-directional composite or light-framed structures. Validation on 90 real-world cases demonstrated a 99.9% weighted average adjusted Rand index for semantic clustering, a 99.5% weighted F1-score for layer function assignment, a 92.7% weighted F1-score for object type classification, and 100% accuracy in BIM object generation. This method is expected to enable a more complete 2D-to-BIM conversion by complementing geometric reconstruction with semantically rich material layer information.

关键词： 工程管理类专业   CAD   基础绘图CAD   专业建模CAD   教学改革  

摘要： CAD课程是工程管理类专业较重要的专业基础课,可以分为基础绘图CAD和专业建模CAD两大板块。分析工程管理类专业基础绘图CAD与专业建模CAD教学内容构成和教学软件选用,分别从教学目标、教学内容、教学方法等维度分析CAD课程教学存在的主要问题,进而提出CAD课程教学改革的总体方案。经过三届学生的教学实践,取得较好的教学效果,可以为相关专业CAD课程教学改革提供有益参考。

关键词： 同比增长   纺织品服装   出口额   海关总署  

摘要： 根据海关总署统计,今年1—2月,全国纺织品服装累计出口额为504.5亿美元,同比增长17.6%,较上年同期增速回升22.1个百分点。其中,纺织品出口额为255.7亿美元,同比增长20.5%,延续去年以来的良好增长态势;服装出口额为248.7亿美元,同比增长14.8%,增幅迅速扩大。

关键词： 复方桔梗止咳片   桔梗皂苷   远志皂苷   异绿原酸   甘草苷   甘草酸   高效液相色谱-电雾式检测器   指纹图谱   含量测定   化学计量学   质量评价  

摘要： 目的:基于高效液相色谱-电雾式检测器(HPLC-CAD)建立复方桔梗止咳片指纹图谱和多成分定量分析方法,结合化学计量学评价31批次不同企业生产的复方桔梗止咳片的质量差异。方法:采用Agilent Zorbax Eclipse XDB C_(18)色谱柱(250 mm×4.6 mm,5μm),以乙腈-0.1%甲酸水为流动相进行梯度洗脱,体积流量为1.0 mL·min^(-1),柱温为35℃,电雾式检测器(CAD)幂函数值为1.1,进样量为10μL。指纹图谱分析标定28个共有峰,通过对照品指认出桔梗皂苷E、桔梗皂苷D_(3)、远志酮Ⅲ等12个成分,并建立其含量测定方法。结果:30批(1批除外)样品相似度>0.90,表明建立的指纹图谱可有效表征复方桔梗止咳片整体质量。化学模式识别分析(层次聚类分析、主成分分析及正交偏最小二乘法-判别分析)表明,31批次样品可聚类为6组,筛选出15个潜在差异性成分。进一步定量分析显示,31批制剂中桔梗类(桔梗皂苷E、桔梗皂苷D_(3)、桔梗皂苷D)、远志类(远志酮Ⅲ、3,6’-二芥子酰基蔗糖、细叶远志皂苷、远志皂苷B)、款冬花类(异绿原酸B、异绿原酸A、异绿原酸C)、甘草类(甘草苷、甘草酸)成分质量分数分别为0.949~2.546、0.942~2.128、0.128~0.810和0.240~0.744 mg·g^(-1)。结论:该研究建立的方法简便、准确,可实现基于HPLC-CAD指纹图谱和多成分含量测定的复方桔梗止咳片质量控制,并系统揭示不同厂家复方桔梗止咳片的质量差异,为其质量标准提升及生产工艺优化提供科学依据。

关键词： Boundary representation   CAD model   Classification   Graph convolutional network   Segmentation  

摘要： The widespread adoption of 3D CAD models in intelligent manufacturing and digital twin systems demands efficient and accurate classification and segmentation. While effective approaches typically model geometry and topology jointly using B-rep face-edge graphs, prevailing methods rely heavily on auxiliary information (e.g., supplemental geometry/semantics) to compensate for perceived shortcomings in raw B-rep data. This dependency incurs high preprocessing overhead, limits cross-platform generalization, and hinders industrial deployment. Furthermore, inherent redundancies within B-rep graphs can obscure essential semantics during encoding. To overcome these limitations, we propose UVConv, an end-to-end dual-path framework that operates exclusively on the original UV grid and face adjacency graph, eliminating auxiliary inputs. UVConv employs a serial geometry-topology processing: the geometric encoder utilizes bottleneck compression to amplify discriminative features, while the topological encoder integrates a Bidirectional Interaction Module (BIM) and an Attention Filtering Module (AFM) to extract critical structural semantics and suppress noise. Comprehensive experiments on multiple benchmark CAD datasets demonstrate that UVConv matches or surpasses state-of-the-art performance without auxiliary data, exhibiting superior representational capacity, robust generalization, and enhanced industrial deployability.