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Type WYZ-97 Eighteen information Noninsulate Frequency shift Automatic Blocking System
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作者 陈志龙 《High Technology Letters》 EI CAS 2000年第3期38-39,共2页
Type WYZ 97 eighteen information noninsulate frequency shift automatic blocking system is the most advanced railroad signaling system in China nowadays.The article introduced its principles,technical targets,features ... Type WYZ 97 eighteen information noninsulate frequency shift automatic blocking system is the most advanced railroad signaling system in China nowadays.The article introduced its principles,technical targets,features and the applications. 展开更多
关键词 Frequency shift automatic blocking Noninsulate Eighteen information
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Automatic identification of rock discontinuity and stability analysis of tunnel rock blocks using terrestrial laser scanning 被引量:8
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作者 Meng Wang Jiawen Zhou +3 位作者 Junlin Chen Nan Jiang Puwen Zhang Haibo Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第7期1810-1825,共16页
Local geometric information and discontinuity features are key aspects of the analysis of the evolution and failure mechanisms of unstable rock blocks in rock tunnels.This study demonstrates the integration of terrest... Local geometric information and discontinuity features are key aspects of the analysis of the evolution and failure mechanisms of unstable rock blocks in rock tunnels.This study demonstrates the integration of terrestrial laser scanning(TLS)with distinct element method for rock mass characterization and stability analysis in tunnels.TLS records detailed geometric information of the surrounding rock mass by scanning and collecting the positions of millions of rock surface points without contact.By conducting a fuzzy K-means method,a discontinuity automatic identification algorithm was developed,and a method for obtaining the geometric parameters of discontinuities was proposed.This method permits the user to visually identify each discontinuity and acquire its spatial distribution features(e.g.occurrences,spac-ings,trace lengths)in great detail.Compared with hand mapping in conventional geotechnical surveys,the geometric information of discontinuities obtained by this approach is more accurate and the iden-tification is more efficient.Then,a discrete fracture network with the same statistical characteristics as the actual discontinuities was generated with the distinct element method,and a representative nu-merical model of the jointed surrounding rock mass was established.By means of numerical simulation,potential unstable rock blocks were assessed,and failure mechanisms were analyzed.This method was applied to detection and assessment of unstable rock blocks in the spillway and sand flushing tunnel of the Hongshiyan hydropower project after a collapse.The results show that the noncontact detection of blocks was more labor-saving with lower safety risks compared with manual surveys,and the stability assessment was more reliable since the numerical model built by this method was more consistent with the distribution characteristics of actual joints.This study can provide a reference for geological survey and unstable rock block hazard mitigation in tunnels subjected to complex geology and active rockfalls. 展开更多
关键词 Rock tunnel Terrestrial laser scanning(TLS) Discontinuity automatic identification Distinct element method Rock block stability assessment
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Automatic Identification of Butterfly Species Based on Gray-Level Co-occurrence Matrix Features of Image Block 被引量:4
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作者 XUE Ankang LI Fan XIONG Yin 《Journal of Shanghai Jiaotong university(Science)》 EI 2019年第2期220-225,共6页
In recent years, automatic identification of butterfly species arouses more and more attention in different areas. Because most of their larvae are pests, this research is not only meaningful for the popularization of... In recent years, automatic identification of butterfly species arouses more and more attention in different areas. Because most of their larvae are pests, this research is not only meaningful for the popularization of science but also important to the agricultural production and the environment. Texture as a notable feature is widely used in digital image recognition technology; for describing the texture, an extremely effective method, graylevel co-occurrence matrix(GLCM), has been proposed and used in automatic identification systems. However,according to most of the existing works, GLCM is computed by the whole image, which likely misses some important features in local areas. To solve this problem, this paper presents a new method based on the GLCM features extruded from three image blocks, and a weight-based k-nearest neighbor(KNN) search algorithm used for classifier design. With this method, a butterfly classification system works on ten butterfly species which are hard to identify by shape features. The final identification accuracy is 98%. 展开更多
关键词 automatic identification butterfly species gray-level co-occurrence matrix(GLCM) features of image block
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Energy Saving for Automatic Train Control in Moving Block Signaling System
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作者 GU Qing MENG Yu MA Fei 《China Communications》 SCIE CSCD 2014年第A02期12-22,共11页
With rapid development of the railway traffic, the moving block signaling system (MBS) method has become more and more important for increasing the track capacity by allowing trains to run in a shorter time-headway ... With rapid development of the railway traffic, the moving block signaling system (MBS) method has become more and more important for increasing the track capacity by allowing trains to run in a shorter time-headway while maintaining the required safety margins. In this framework, the tracking target point of the following train is moving forward with its leading train. This paper focuses on the energy saving tracking control of two successive trains in MBS. Nonlinear programming method is used to optimize the energy-saving speed trajectory of the following train. The real-time location of the leading train could be integrated into the optimization process. Due to simplicity, it can be used for online implementation. The feasibility and effectiveness are verified through simulation. The results show that the new method is efficient on energy saving even when disturbances present. 展开更多
关键词 moving block signaling (MBS) energy saving automatic train protection (ATP) automatic train operation (ATO) TRACKING train speed trajectory
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Anesthetic management of patient with hypertrophic cardiomyopathy and automatic implantable cardioverter defibrillator with a hand fracture
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作者 Jaime Ortiz 《World Journal of Anesthesiology》 2013年第1期8-10,共3页
A 26-year-old male with a history of hypertrophic cardiomyopathy(HCM) and ventricular arrhythmias s/p automatic implantable cardioverter defibrillator(AICD) placement presented for open reduction and internal fixation... A 26-year-old male with a history of hypertrophic cardiomyopathy(HCM) and ventricular arrhythmias s/p automatic implantable cardioverter defibrillator(AICD) placement presented for open reduction and internal fixation of an open third metacarpal fracture and extensor tendon repair. He underwent successful surgery after placement of an ultrasound-guided infraclavicular brachial plexus block with ropivacaine 0.5% as the main anesthetic. This case report discusses the anesthetic management of patients with HCM and AICD, different approaches available for brachial plexus blockade, and potential complications of anesthesia and surgery in this group of patients. 展开更多
关键词 Hypertrophic cardiomyopathy automatic implantable cardioverter DEFIBRILLATOR BRACHIAL plexus block HAND FRACTURE ROPIVACAINE
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CMS-YOLO:An Automated Multi-Category Brain Tumor Detection Algorithm Based on Improved YOLOv10s
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作者 Li Li Xiao Wang +3 位作者 Ran Ding Linlin Luo Qinmu Wu Zhiqin He 《Computers, Materials & Continua》 2025年第10期1287-1309,共23页
Brain tumors are neoplastic diseases caused by the proliferation of abnormal cells in brain tissues,and their appearance may lead to a series of complex symptoms.However,current methods struggle to capture deeper brai... Brain tumors are neoplastic diseases caused by the proliferation of abnormal cells in brain tissues,and their appearance may lead to a series of complex symptoms.However,current methods struggle to capture deeper brain tumor image feature information due to the variations in brain tumor morphology,size,and complex background,resulting in low detection accuracy,high rate of misdiagnosis and underdiagnosis,and challenges in meeting clinical needs.Therefore,this paper proposes the CMS-YOLO network model for multi-category brain tumor detection,which is based on the You Only Look Once version 10(YOLOv10s)algorithm.This model innovatively integrates the Convolutional Medical UNet extended block(CMUNeXt Block)to design a brand-new CSP Bottleneck with 2 convolutions(C2f)structure,which significantly enhances the ability to extract features of the lesion area.Meanwhile,to address the challenge of complex backgrounds in brain tumor detection,a Multi-Scale Attention Aggregation(MSAA)module is introduced.The module integrates features of lesions at different scales,enabling the model to effectively capture multi-scale contextual information and enhance detection accuracy in complex scenarios.Finally,during the model training process,the Shape-IoU loss function is employed to replace the Complete-IoU(CIoU)loss function for optimizing bounding box regression.This ensures that the predicted bounding boxes generated by the model closely match the actual tumor contours,thereby further enhancing the detection precision.The experimental results show that the improved method achieves 94.80%precision,93.60%recall,96.20%score,and 79.60%on the MRI for Brain Tumor with Bounding Boxes dataset.Compared to the YOLOv10s model,this represents improvements of 1.0%,1.1%,1.0%,and 1.1%,respectively.The method can achieve automatic detection and localization of three distinct categories of brain tumors—glioma,meningioma,and pituitary tumor,which can accurately detect and identify brain tumors,assist doctors in early diagnosis,and promote the development of early treatment. 展开更多
关键词 Brain tumor deep learning automatic detection YOLOv10s CMUNeXt block MSAA Shape-IoU
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汽车覆盖件模面设计中翻边刀块自动生成方法
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作者 柯文浩 柳玉起 +1 位作者 章志兵 王振 《锻压技术》 北大核心 2026年第1期299-307,共9页
为解决翻边刀块设计自动化程度低且效率低的问题,提出了一种翻边刀块曲面自动生成的方法,能够实现翻边刀块曲面的快速设计。该方法将翻边刀块曲面分为底部面、立壁面和圆角面3个部分。通过滚圆算法横向偏置出底部面下引导线并调整截面... 为解决翻边刀块设计自动化程度低且效率低的问题,提出了一种翻边刀块曲面自动生成的方法,能够实现翻边刀块曲面的快速设计。该方法将翻边刀块曲面分为底部面、立壁面和圆角面3个部分。通过滚圆算法横向偏置出底部面下引导线并调整截面线端点位置以合理布置截面线,实现了底部面的高质量生成;采取扫掠和填充两种方式生成立壁面,并根据翻边面特征调整立壁面截面线的延伸方向,提高立壁面生成的稳定性和质量;采用基于圆角截面线的方式扫掠生成圆角面,解决了滚球法倒圆角中曲率半径小于倒圆角半径而出现无法倒圆角的情况。基于HiStamp平台开发了翻边刀块曲面自动生成功能,实现了翻边刀块曲面的自动化设计。经测试,该功能可根据输入参数,高效且稳定地完成翻边刀块曲面的设计,有效缩短翻边刀块的研发周期。 展开更多
关键词 汽车覆盖件 翻边刀块 自动设计 曲面生成 截面线
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基于设置接近限速的高铁列车到达间隔时间压缩方法
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作者 盛天一 安迪 +2 位作者 田志强 刘洋 刘坦 《中国铁路》 北大核心 2026年第2期174-180,共7页
提升繁忙高速铁路通过能力、合理压缩列车追踪间隔时间一直以来都是铁路运营部门需要重点解决的难题,而列车到达间隔时间较长是缩短列车追踪间隔时间的主要瓶颈。针对这一问题,通过分析区间限速设置对列车到达追踪运行影响机理,从空间... 提升繁忙高速铁路通过能力、合理压缩列车追踪间隔时间一直以来都是铁路运营部门需要重点解决的难题,而列车到达间隔时间较长是缩短列车追踪间隔时间的主要瓶颈。针对这一问题,通过分析区间限速设置对列车到达追踪运行影响机理,从空间和时间2个视角出发,提出列车到达间隔时间计算模型,对接近限速条件下列车追踪进站作业过程进行检算,并对模型参数值进行标定,以案例计算方式验证模型有效性。计算结果表明,进站接近位置一定范围内设置适当限速可有效缩短列车到达间隔时间,同时区间追踪间隔和区间运行时分的扩大在合理范围内,在提升车站通过能力的同时,能够更好适应高速铁路旅客快速便捷的乘车需求。 展开更多
关键词 高速铁路 列车到达间隔时间 列车追踪间隔时间 车站通过能力 限速
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基于深度学习的前路坐骨神经超声图像分割
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作者 贾尚超 常兆斌 +3 位作者 陈青峰 赵大成 徐大赓 黄生辉 《兰州大学学报(医学版)》 2026年第2期23-29,共7页
目的构建一套超声影像数据集,建立基于深度学习的超声图像识别系统,用以探索前入路区域坐骨神经阻滞区域的识别方法。方法通过超声采集前路坐骨神经图像,借助ITK-SNAP软件手动标记,建立数据集。采用PyTorch深度学习框架进行训练数据及... 目的构建一套超声影像数据集,建立基于深度学习的超声图像识别系统,用以探索前入路区域坐骨神经阻滞区域的识别方法。方法通过超声采集前路坐骨神经图像,借助ITK-SNAP软件手动标记,建立数据集。采用PyTorch深度学习框架进行训练数据及感兴趣区域分割输出,以平均交并比、平均骰子相似系数作为评价指标评估模型的性能。结果以获得的3000张标记超声图像作为数据集,其中,训练集1800张,验证集600张,测试集600张。测试集坐骨神经的平均交并比为0.675,平均骰子相似系数为0.775,模型平均F1分数为0.718,中位数为0.720。经5折交叉验证,坐骨神经的平均交并比中位数为0.805。结论基于深度学习模型,在自动识别前入路区域坐骨神经解剖结构时获得了良好效果,可实现局麻药在神经旁间隙的安全、精准注射,具有良好的临床应用价值。 展开更多
关键词 深度学习 前路坐骨神经 超声 图像识别 三元注意力网络 自动分割 神经阻滞
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CAM-ResNet:基于ResNet的土地利用类型遥感图像分类
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作者 王梓鉴 方建军 +1 位作者 袁涌博 刘泽宇 《北京联合大学学报》 2026年第1期49-54,共6页
在土地利用类型图像分类领域,传统分类方法在特征提取准确性与分类精度方面存在局限性,难以满足实际应用需求。本文以ResNet50为核心架构,引入卷积块注意力模块(convolutional block attention module,CBAM),强化特征提取,并采用自动混... 在土地利用类型图像分类领域,传统分类方法在特征提取准确性与分类精度方面存在局限性,难以满足实际应用需求。本文以ResNet50为核心架构,引入卷积块注意力模块(convolutional block attention module,CBAM),强化特征提取,并采用自动混合精度(automatic mixed precision,AMP)技术提高计算效率,构建了CAM-ResNet网络。实验结果显示,CAM-ResNet网络的总体精度达98.19%,较原网络高出10.16个百分点。消融实验进一步证明,CBAM注意力机制显著增强了模型的特征提取能力,AMP训练技术提高了模型的收敛速度,CAM-ResNet网络在土地利用类型遥感图像分类中具有一定的有效性和优越性。 展开更多
关键词 土地利用 ResNet50 卷积块注意力模块(CBAM) 自动混合精度(AMP) 图像分类 卷积神经网络(CNN)
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基于状态控制的冷冻鱼块双向定量切割技术研究
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作者 张文霞 袁健 《包装与食品机械》 北大核心 2026年第1期22-30,共9页
为满足冷冻鱼块深加工对切割精度与效率的要求,设计一种基于X-Y直角坐标系的自动切割机控制系统,并提出基于流程状态切换的双向定量切割方法。系统以PLC为核心,集成人机界面(HMI)、双伺服系统、多组传感器、电磁阀-气缸执行机构及变频... 为满足冷冻鱼块深加工对切割精度与效率的要求,设计一种基于X-Y直角坐标系的自动切割机控制系统,并提出基于流程状态切换的双向定量切割方法。系统以PLC为核心,集成人机界面(HMI)、双伺服系统、多组传感器、电磁阀-气缸执行机构及变频调速装置,构建模块化、可重构的控制架构。通过状态图控制,实现切割平台的高精度往复运动与双向交替切割;配合尺寸自适应、切割片数智能计算与首尾厚度补偿动态调整进给步距,提升切割一致性与成品率。结果表明,系统在保持单位切割时间不变的前提下,与单向切割方法相比,整体切割周期缩短约12.5%,每日节省系统运行时间超过1 h;将切片厚度误差控制在±0.1 mm以内。研究为冷冻水产的精深加工提供高效解决方案。 展开更多
关键词 冷冻鱼块 定量切割 双向控制 自动切割机 伺服控制系统
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市域铁路列控系统仿真测试平台研究及应用
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作者 伍田昊睿 杨俐 +3 位作者 黄琨 张浩 李国强 徐强 《中国铁路》 北大核心 2026年第1期102-109,共8页
为满足市域铁路“高密度、快启停、多场景”运营需求,针对传统列控系统测试方式效率低及现有仿真平台的不足,围绕基于CTCS的市域铁路移动闭塞列控系统(CTCS-Y)及仿真测试平台开展研究。梳理列控系统发展历程,明确CTCS-Y在多源定位、车... 为满足市域铁路“高密度、快启停、多场景”运营需求,针对传统列控系统测试方式效率低及现有仿真平台的不足,围绕基于CTCS的市域铁路移动闭塞列控系统(CTCS-Y)及仿真测试平台开展研究。梳理列控系统发展历程,明确CTCS-Y在多源定位、车地冗余通信等方面的优势;针对现有平台不足,采用模块化设计构建平台,集成TIS-RBC接口仿真、自动折返测试等模块,结合硬件在环(HIL)技术和模型驱动设计,补全特殊场景测试能力。以上海南汇支线为背景,设计7类典型测试序列,开展46个序列验证。测试结果表明:该平台能有效覆盖市域铁路全场景,对CTCS-Y系统功能及线路数据具备有效的验证能力,可为列控系统研发、联调联试及测试提供技术支撑。 展开更多
关键词 市域铁路 列控系统 CTCS-Y 仿真测试平台 移动闭塞 自动折返
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计算机站间闭塞系统的研究
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作者 纪英杰 陈强 +3 位作者 王晓辉 陶晶 刘重均 张伟 《铁路通信信号工程技术》 2026年第2期48-55,共8页
针对国内单线铁路广泛应用的64D型继电半自动闭塞/自动站间闭塞系统存在的传输可靠性低、可维护性差、可扩展性弱、故障智能化诊断及定位不易实现等问题,研究并设计基于安全计算机技术、安全通信技术及车轮电磁探测技术的计算机站间闭... 针对国内单线铁路广泛应用的64D型继电半自动闭塞/自动站间闭塞系统存在的传输可靠性低、可维护性差、可扩展性弱、故障智能化诊断及定位不易实现等问题,研究并设计基于安全计算机技术、安全通信技术及车轮电磁探测技术的计算机站间闭塞系统。该系统实现站间闭塞、安全信息传输与区间占用检查的一体化功能,通过软件化实现闭塞逻辑电路,采用冗余设计提升可靠性,既兼容既有联锁继电接口,也具备扩展通信接口功能。实际应用表明,系统可简化设备构成、降低工程成本、提高故障定位效率,满足铁路信号系统安全与发展需求。 展开更多
关键词 计算机站间闭塞 64D继电电路 半自动闭塞 自动站间闭塞 冗余设计 安全设计 计轴
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Design and test of the progressive push-out automatic seedling-taking device for vegetable substrate block seedlings
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作者 Zhichao Cui Jingjing Fu +8 位作者 Jicheng Li Haibo Ji Changhao Wu Shuhe Zheng Tiqiong Xiao Yongsheng Chen Chenghao Zhang Yating Yang Chunsong Guan 《International Journal of Agricultural and Biological Engineering》 2025年第4期89-100,共12页
Aiming at the problems of low success rate and high seedling injury rate of automatic vegetable transplanting,this study focused on cabbage substrate block seedlings and developed a progressive push-out automatic seed... Aiming at the problems of low success rate and high seedling injury rate of automatic vegetable transplanting,this study focused on cabbage substrate block seedlings and developed a progressive push-out automatic seedling device controlled by a PLC system.Based on the friction mechanical properties of seedlings-tray during seedling taking,the collision rebound theoretical analysis of substrate block seedling delivery and the finite element simulation analysis of the seedling taking mechanism were carried out to determine the conditions for stable seedling taking and delivery of the device and the working parameters of the key mechanisms.To evaluate individual parameter effects,a test bench was built,and the effective ranges of key factors were subsequently determined.Three key experimental factors,the inclination angle of the limit guide plate,the seedling separation channel width,and the seedling separation cylinder pressure,were investigated using an L9(34)orthogonal array design with blockage rate and breakage rate as evaluation metrics.The range and variance analysis methods were employed to determine the relative significance of each factor’s influence on the performance indicators.The optimal parameters were determined as:the inclination angle of the limiting guide plate was 3.5°,the width of the seedling separation channel was 50 mm,and the pressure of the seedling separation cylinder was 0.6 MPa.Under these conditions,the seedling taking effect was significantly improved:the blockage rate was 2.46%,the breakage rate was 3.18%,and the seedling taking success rate was 94.36%.The optimal parameter combination was verified by the experiment:the average blockage rate was 3.23%,the average breakage rate was 3.68%,and the average success rate was 93.09%.Compared with the orthogonal experiment,the relative success rate error was 1.27%,indicating that the device has high stability.This study will provide a reference for the design of automatic vegetable transplanters. 展开更多
关键词 transplanter substrate block seedlings automatic seedling taking device PLC control system progressive push-out
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列控联锁一体化系统综合仿真测试平台设计与实现
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作者 王拓 蓝晓庆 +3 位作者 王良胜 李世巍 孔嘉铖 罗梓豪 《铁道通信信号》 2026年第2期47-54,共8页
针对既有列控联锁一体化系统(TIS)仿真测试平台环境配置复杂、功能不完善、接口类型繁多等问题,设计并实现了一种TIS综合仿真测试平台。该平台主要包括图形化站场界面模块、仿真子系统模块和自动测试模块3部分。图形化站场界面模块采用... 针对既有列控联锁一体化系统(TIS)仿真测试平台环境配置复杂、功能不完善、接口类型繁多等问题,设计并实现了一种TIS综合仿真测试平台。该平台主要包括图形化站场界面模块、仿真子系统模块和自动测试模块3部分。图形化站场界面模块采用WPF显示框架,可实时展示站场设备状态,并支持通过统一的站场界面操作多种类型的后台对象状态;仿真子系统模块集成了9种接口仿真子系统,基于标准协议与TIS逻辑主机通信,并实现与列控系统仿真测试平台的信息交互,可模拟测试所需的各类轨旁设备状态;自动测试模块可实现测试用例的自动分解和执行,并提供调度集中通信接口的自动测试功能。应用结果表明:该测试平台可有效减少接口数量,简化测试平台架构,降低测试环境搭建难度,提升测试效率,未来可为TIS的技术迭代及工程化应用提供有力支撑。 展开更多
关键词 列控联锁一体化系统 移动闭塞列控系统 仿真测试平台 自动测试 图形化站场界面
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Automation of choice of instrumental equipment and study of thermo-stressed conditions of metal-cutting instrument
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作者 Anatoly V.Levchenko Roman A.Eshenko Olga I.Skarlykina 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2000年第S1期87-87,共1页
This article about possibility of automations of choice of instrumental equipment. In it described problems of choice of equipment, which are decided by means of mathematical model, developed on the base of finite ele... This article about possibility of automations of choice of instrumental equipment. In it described problems of choice of equipment, which are decided by means of mathematical model, developed on the base of finite element method. 展开更多
关键词 automatization INSTRUMENTAL EQUIPMENT mathematical model arrangement INSTRUMENTAL block metal-cutting instrument thermal-stressed condition finite element method
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基于Automation的AutoCAD块图库管理系统
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作者 许林 《机械与电子》 2000年第1期46-48,共3页
针对AutoCAD 中块图形管理功能较弱,提出块图库管理系统的研究。管理系统采用Au-tom ation 客户/服务器方式,用VB6 开发管理系统,实现了与AutoCAD的信息交换,采用Access 管理信息,操作界面实... 针对AutoCAD 中块图形管理功能较弱,提出块图库管理系统的研究。管理系统采用Au-tom ation 客户/服务器方式,用VB6 开发管理系统,实现了与AutoCAD的信息交换,采用Access 管理信息,操作界面实现可视化。 展开更多
关键词 自动化服务器 机械产品 AUTOCAD 块图库
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基于自动权重的主动块对角子空间聚类
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作者 李向利 谢腾翅 韦嘉逢 《吉林大学学报(理学版)》 北大核心 2025年第6期1673-1684,共12页
针对传统基于谱聚类的子空间聚类方法在高维数据存在离群点时,易受离群点干扰而导致聚类性能下降的问题,提出一种基于自动权重的主动块对角子空间聚类方法.该方法先为每个数据点赋予相应权重,通过权重差异识别数据中的离群点.在确定离... 针对传统基于谱聚类的子空间聚类方法在高维数据存在离群点时,易受离群点干扰而导致聚类性能下降的问题,提出一种基于自动权重的主动块对角子空间聚类方法.该方法先为每个数据点赋予相应权重,通过权重差异识别数据中的离群点.在确定离群点后,主动降低其在表示矩阵中的贡献度,进而构建更优的表示矩阵以提升模型的聚类性能.在10个数据集上与8种对比算法的实验结果表明:在含10%,20%离群点的数据集上,该方法的平均聚类准确率、归一化互信息、调整Rand指数等指标普遍优于对比算法;在一般聚类任务中,其在超过半数数据集上性能最优或位居前三.因此该方法既能高效处理含离群点的高维数据聚类,又能在通用聚类任务中保持竞争力,为提高高维数据聚类的鲁棒性提供了有效方案,有较高的实际应用价值. 展开更多
关键词 子空间聚类 离群点 自动权重 块对角方法
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基于5G LDPC码的增强耦合编码及HARQ设计 被引量:1
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作者 杨佳仪 王千帆 +3 位作者 毕胜 谭志远 韦宝典 马啸 《移动通信》 2025年第2期58-64,共7页
针对CB级反馈场景,提出了一种基于现有的5G标准低密度一致校验码的增强耦合编码与混合自动重传方案,旨在提升5G链路数据传输的可靠性并改善其吞吐性能。具体而言,在FEC设计方面,基于5G LDPC码引入分组马尔可夫叠加传输技术,设计了BMST-5... 针对CB级反馈场景,提出了一种基于现有的5G标准低密度一致校验码的增强耦合编码与混合自动重传方案,旨在提升5G链路数据传输的可靠性并改善其吞吐性能。具体而言,在FEC设计方面,基于5G LDPC码引入分组马尔可夫叠加传输技术,设计了BMST-5G-LDPC码,通过部分叠加耦合机制有效提升了传输可靠性;在HARQ设计方面,基于BMST-5G-LDPC码提出了一种兼容型HARQ方案,支持增量冗余IR和重复冗余RR机制。为进一步改善吞吐性能,特别提出了部分重传HARQ方案,通过对错误CB的部分比特进行重组并重传,节省信道传输资源改善吞吐性能,并同样支持IR和RR部分重传设计。仿真结果表明,所设计的BMST-5G-LDPC码在准静态衰落信道下相比传统5G LDPC码有约1.25 dB的性能增益;对于HARQ设计,兼容型HARQ设计相比于传统IR-HARQ方案,有10%以上吞吐增益;特别地,采用IR机制的PR-HARQ相比于传统IR-HARQ方案在中高噪比有20%以上的吞吐增益。 展开更多
关键词 5G 低密度一致校验码 混合自动重传 分组马尔可夫叠加传输
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面向船体分段吊装工艺的多功能设计系统开发
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作者 张全有 李瑞 +1 位作者 战修广 刘玉君 《华中科技大学学报(自然科学版)》 北大核心 2025年第4期72-78,共7页
基于船体分段AM模型抽取的离散数据与三角剖分数据、吊装工艺信息、起重设备信息等,提出了船体分段吊点布置优化算法;基于高可靠的AFT-Delaunay(自动有限元-德劳内)网格生成算法,以及包含控制算法、单元计算与本构计算扩展接口等功能的... 基于船体分段AM模型抽取的离散数据与三角剖分数据、吊装工艺信息、起重设备信息等,提出了船体分段吊点布置优化算法;基于高可靠的AFT-Delaunay(自动有限元-德劳内)网格生成算法,以及包含控制算法、单元计算与本构计算扩展接口等功能的有限元分析框架,开发了面向船体分段吊装工艺的多功能集成设计系统;为解决船体分段吊装工艺设计环节中的吊点布置自动求解问题、船体分段吊装过程工艺动态仿真问题、眼板与分段的网格剖分问题及有限元自动计算等问题提供了自动化解决方案.最后以某原油船的舭部分段为例,对比商业有限元软件MSC.NASTRAN与本系统在有限元计算结果、网格剖分及有限元可视化显示等方面的功能,证明本系统在船体分段吊装安全性评估方面达到与商用有限元软件相当水平. 展开更多
关键词 分段吊装 吊点布置 吊点自识别算法 网格剖分 动态仿真
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