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基于3D Tiles的大规模三维地质模型共享技术研究
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作者 吴龙华 侯建光 +1 位作者 朱月霞 李运杰 《物探化探计算技术》 CAS 2024年第2期242-250,共9页
针对三维地质模型的网络共享与发布研究较少,基于3D Tiles提出了一种大规模三维地质模型共享发布方案:首先采用基于二次误差测度(QEM)的半边折叠算法,对模型进行简化,建立分层LOD模型;再利用平面四叉树+纵向固定距离切分的方法对各级模... 针对三维地质模型的网络共享与发布研究较少,基于3D Tiles提出了一种大规模三维地质模型共享发布方案:首先采用基于二次误差测度(QEM)的半边折叠算法,对模型进行简化,建立分层LOD模型;再利用平面四叉树+纵向固定距离切分的方法对各级模型进行分块,建立瓦片分层结构树;最后计算出所需的几何误差、变换矩阵等参数,并生成3D Tiles瓦片内容及瓦片集描述文件。基于此方案选取了某区域约1000 km^(2)的三维地质体模型进行了实验,实验表明该方案在保障模型的几何特征和细节表现的同时,可对大规模三维地质模型进行高效、流畅的加载与显示。 展开更多
关键词 3D tiles 共享与发布 三维地质 CESIUM
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3D打印技术下空心螺钉微创固定对Tile B型骨盆骨折的近期疗效及并发症的影响
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作者 凌坤 王旭 +2 位作者 唐洪 郭建斌 曹桂花 《中国医药指南》 2023年第28期77-79,共3页
目的 探究3D打印技术下空心螺钉微创固定对Tile B型骨盆骨折的近期疗效及并发症的影响。方法 选取四川省广元市中心医院2019年6月至2022年10月收治的80例Tile B型骨盆骨折患者作为研究对象,按照Excel软件随机分组方法分为对照组(40例)... 目的 探究3D打印技术下空心螺钉微创固定对Tile B型骨盆骨折的近期疗效及并发症的影响。方法 选取四川省广元市中心医院2019年6月至2022年10月收治的80例Tile B型骨盆骨折患者作为研究对象,按照Excel软件随机分组方法分为对照组(40例)与观察组(40例),对照组采用空心螺钉微创固定治疗方法,观察组采用3D打印技术下空心螺钉微创固定治疗方法。比较两组患者治疗指标(手术时间、术中透视次数、伤口愈合时间、功能恢复时间)、治疗效果、并发症发生率及治疗满意度。结果 观察组患者手术时间、伤口愈合时间、功能恢复时间均短于对照组,术中透视次数少于对照组(均P<0.001);观察组治疗有效率高于对照组(90.0%vs. 67.5%,P=0.014);观察组并发症发生率较对照组低(7.5%vs. 27.5%,P=0.019);观察组治疗满意度高于对照组(95.0%vs. 75.0%,P=0.012)。结论 3D打印技术下空心螺钉微创固定治疗Tile B型骨盆骨折可取得良好的治疗效果,能缩短手术时间,促进患者伤口愈合,加快骨盆功能恢复,减少术中透视次数,并能降低患者并发症发生率,使患者获得较高的治疗满意度。 展开更多
关键词 3D打印技术 空心螺钉微创固定 tile B型骨盆骨折 并发症
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INFIX技术与外固定支架分别联合骶髂关节螺钉治疗Tile B型骨折的效果观察 被引量:1
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作者 陈林 刘东 +2 位作者 王志强 温洋 罗兰 《河北医学》 CAS 2023年第5期844-849,共6页
目的:探讨前环皮下内置外固定架(INFIX)技术与外固定支架分别联合骶髂关节螺钉治疗Tile B型骨折的效果。方法:回顾性分析2019年3月至2022年3月就诊于本院骨科的88例Tile B型骨折患者,其中47例给予INFIX技术+骶髂关节螺钉治疗(INFIX组),4... 目的:探讨前环皮下内置外固定架(INFIX)技术与外固定支架分别联合骶髂关节螺钉治疗Tile B型骨折的效果。方法:回顾性分析2019年3月至2022年3月就诊于本院骨科的88例Tile B型骨折患者,其中47例给予INFIX技术+骶髂关节螺钉治疗(INFIX组),41例给予外固定支架+骶髂关节螺钉治疗(外固定支架组),比较两组手术时间、术中出血量、住院时间、术后负重时间、愈合时间、并发症发生率、Matta评分、Majeed评分以及术后1、3、6个月EQ-5D评分及VAS评分。结果:INFIX组住院时间及愈合时间均短于外固定支架组,并发症发生率低于外固定支架组(P<0.05);术后6个月,INFIX组Matta评分优良率(95.74%)高于外固定支架组(80.49%)(P<0.05);INFIX组性生活评分高于外固定支架组(P<0.05);EQ-5D评分及VAS评分组间、时间点及交互差异均有统计学意义(P<0.0001),术后1个月及术后3个月INFIX组EQ-5D评分均大于外固定支架组,术后1个月及术后3个月INFIX组VAS评分均小于外固定支架组(P<0.05)。结论:INFIX技术联合骶髂关节螺钉治疗Tile B型骨折临床疗效更好,恢复期短,更有利于患者进行早期功能性锻炼,且并发症发生率较低。 展开更多
关键词 tile B型骨折 INFIX技术 外固定支架 骶髂关节螺钉
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The wave and vibratory power transmission in a finite L-shaped Mindlin plate with two simply supported opposite edges 被引量:7
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作者 Chun-Chuan Liu Feng-Ming Li Ting-Wei Liang Wen-Hu Huang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第5期785-795,共11页
In this paper,wave and vibratory power transmission in a finite L-shaped Mindlin plate with two simply supported opposite edges are investigated using the wave approach.The dynamic responses,active and reactive power ... In this paper,wave and vibratory power transmission in a finite L-shaped Mindlin plate with two simply supported opposite edges are investigated using the wave approach.The dynamic responses,active and reactive power flow in the finite plate are calculated by the Mindlin plate theory (MPT) and classic plate theory (CPT).To satisfy the boundary conditions and continuous conditions at the coupled junction of the finite L-shaped plate,the near-field and far-field waves are entirely contained in the wave approach.The in-plane longitudinal and shear waves are also considered.The results indicate that the vibratory power flow based on the MPT is different from that based on the CPT not only at high frequencies but also at low and medium frequencies.The influence of the plate thickness on the vibrational power flow is investigated.From the results it is seen that the shear and rotary inertia correction of the MPT can influence the active and reactive power at the junction of the L-shaped plate not only at high frequencies but also at low and medium frequencies.Furthermore,the effects of structural damping on the active and reactive power flow at the junction are also analyzed. 展开更多
关键词 Finite l-shaped Mindlin plate Active power flow Reactive power flow Wave approach
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Joint 2D DOA and Doppler frequency estimation for L-shaped array using compressive sensing 被引量:4
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作者 WANG Shixin ZHAO Yuan +3 位作者 LAILA Ibrahim XIONG Ying WANG Jun TANG Bin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第1期28-36,共9页
A joint two-dimensional(2D)direction-of-arrival(DOA)and radial Doppler frequency estimation method for the L-shaped array is proposed in this paper based on the compressive sensing(CS)framework.Revised from the conven... A joint two-dimensional(2D)direction-of-arrival(DOA)and radial Doppler frequency estimation method for the L-shaped array is proposed in this paper based on the compressive sensing(CS)framework.Revised from the conventional CS-based methods where the joint spatial-temporal parameters are characterized in one large scale matrix,three smaller scale matrices with independent azimuth,elevation and Doppler frequency are introduced adopting a separable observation model.Afterwards,the estimation is achieved by L1-norm minimization and the Bayesian CS algorithm.In addition,under the L-shaped array topology,the azimuth and elevation are separated yet coupled to the same radial Doppler frequency.Hence,the pair matching problem is solved with the aid of the radial Doppler frequency.Finally,numerical simulations corroborate the feasibility and validity of the proposed algorithm. 展开更多
关键词 electronic warfare l-shaped array joint parameter estimation L1-norm minimization Bayesian compressive sensing(CS) pair matching
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Laboratory test on the combined cooling effect of L-shaped thermosyphons and thermal insulation on high-grade roadway construction in permafrost regions 被引量:3
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作者 YuanHong Dong,YuanMing Lai,MingYi Zhang,ShuangYang Li State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou,Gansu 730000,China. 《Research in Cold and Arid Regions》 2009年第4期307-315,共9页
With the completion of the Qinghai-Tibetan Railway,economic development of related areas has been greatly accelerated.This,in return,calls for building or upgrading more roadways,especially high-grade roadways.In cold... With the completion of the Qinghai-Tibetan Railway,economic development of related areas has been greatly accelerated.This,in return,calls for building or upgrading more roadways,especially high-grade roadways.In cold regions,the thawing of permafrost can induce settlement damage of and even failure to railway (or roadway) embankments.Thermosyphons (self-powered refrigera-tion devices that are used to help keep the permafrost cool) have proved effective in mitigating thaw settlement by maintaining the thermal stability of the embankments.However,for high-grade roadway embankments of great width,stabilizing or cooling ef-fects of traditional geotechnological measures may be limited.To enhance the cooling effect of thermosyphons,an L-shaped thermosyphon was designed.A laboratory test was carried out to study the combined cooling effect of the L-shaped thermosyphon and thermal insulation applying to roadbed construction.The angle between the evaporator and condenser sections of the L-shaped thermosyphon is 134 degrees,and the L-shaped thermosyphon was inserted into the soil at an angle of 5 degrees with the road surface.The tested results show that the L-shaped thermosyphon is effective in removing heat from a roadway in winter.When the ambient air temperature is lower than the soil temperature,the thermosyphon is active and extracts the heat in the soil around it.When the ambient air temperature is higher than the soil temperature,the thermosyphon is inactive,and no heat is in-jected into the soil through the L-shaped thermosyphon.Compared to embankments with straight thermosyphons,the inner parts of the embankments with L-shaped thermosyphons were significantly cooled.It is hoped that the present study would be useful to the application of L-shaped thermosyphons in the construction of high-grade roadways in cold regions. 展开更多
关键词 l-shaped thermosyphon thermal insulation cooling effect foundation soils high-grade roadway
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Test on mechanical behavior of SRC L-shaped columns under combined torsion and bending moment 被引量:1
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作者 Chen Zongping Ning Fan +2 位作者 Chen Jianjia Liu Xiang Xu Dingyi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2021年第1期161-177,共17页
Investigations of the seismic behavior of steel reinforced concrete L-shaped columns under constant axial compression and cycled bending-shear-torsion load were performed.Six specimens,which considered two parameters,... Investigations of the seismic behavior of steel reinforced concrete L-shaped columns under constant axial compression and cycled bending-shear-torsion load were performed.Six specimens,which considered two parameters,i.e.,the moment ratio of torsion to bending(γ)and the aspect ratio(column length-to-depth ratio,φ),were prepared for the experiment.In this study,the failure process,torsion-displacement hysteresis curves,and flexure-displacement hysteresis curves were obtained.The failure characteristics,mechanical behavior of specimens such as the failure patterns,hysteresis curves,rigidity degradation,ductility and energy dissipation,are analyzed.The experimental research indicated that the major failures of the specimens were bending failure,bending-shear failure and bending-torsion failure as the moment ratio of torsion to bending(γ)increased.The torsion-displacement hysteresis curves were pinched in the middle,formed a slip platform,and the phenomenon of“load drop”occurred after the peak load.The bending-displacement hysteresis curves were plump,which showed that bending capacity of the specimen was better than its torsion capacity.Additionally,the energy dissipation of the specimen was dominated by torsion in the early stage and ultimately governed by the bending moment in the later phase.Test results also indicated that the displacement ductility coefficient and interstory rotation angle of the failure point were less than 3.0 and 1/50,respectively,which means the test specimen performance does not meet the requirement of the Chinese Code for Seismic Design of Buildings(GB 50011-2014)in this respect. 展开更多
关键词 compression-bending-shear-torsion combined action steel reinforced concrete(SRC) l-shaped columns seismic behavior
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Multicut L-Shaped Algorithm for Stochastic Convex Programming with Fuzzy Probability Distribution
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作者 Miaomiao Han Xinshun MA 《Open Journal of Applied Sciences》 2012年第4期219-222,共4页
Two-stage problem of stochastic convex programming with fuzzy probability distribution is studied in this paper. Multicut L-shaped algorithm is proposed to solve the problem based on the fuzzy cutting and the minimax ... Two-stage problem of stochastic convex programming with fuzzy probability distribution is studied in this paper. Multicut L-shaped algorithm is proposed to solve the problem based on the fuzzy cutting and the minimax rule. Theorem of the convergence for the algorithm is proved. Finally, a numerical example about two-stage convex recourse problem shows the essential character and the efficiency. 展开更多
关键词 STOCHASTIC CONVEX PROGRAMMING fuzzy probability DISTRIBUTION TWO-STAGE problem multicut l-shaped algorithm
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Implementation of a 3D WebGIS for Dynamic Geo-Referencing of 3D Tiles on the Virtual Globe
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作者 Kyongil Woo Adrian Onsen Wonsok Kim 《Journal of Geographic Information System》 2023年第5期440-457,共18页
Needs for real-time interactive visualization of 3D Tiles for massive 3D content on the web-based virtual globe is rapidly increasing, and to achieve this goal, 3D Tiles needs to be correctly geo-referenced to other g... Needs for real-time interactive visualization of 3D Tiles for massive 3D content on the web-based virtual globe is rapidly increasing, and to achieve this goal, 3D Tiles needs to be correctly geo-referenced to other geospatial data on a web-based virtual globe. It is possible to generate 3D Tiles from different kinds of spatial data through various software tools. However, due to various factors the 3D Tile datasets are often poorly or not at all geo-referenced. To tackle this issue, we propose a new 3D WebGIS framework that facilitates dynamic geo-referencing 3D Tiles on the CesiumJS virtual globe. 展开更多
关键词 3D tiles 3D WebGIS CesiumJS Geo-Referencing Virtual Globe
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A Sketch-Based Generation Model for Diverse Ceramic Tile Images Using Generative Adversarial Network
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作者 Jianfeng Lu Xinyi Liu +2 位作者 Mengtao Shi Chen Cui Mahmoud Emam 《Intelligent Automation & Soft Computing》 SCIE 2023年第9期2865-2882,共18页
Ceramic tiles are one of the most indispensable materials for interior decoration.The ceramic patterns can’t match the design requirements in terms of diversity and interactivity due to their natural textures.In this... Ceramic tiles are one of the most indispensable materials for interior decoration.The ceramic patterns can’t match the design requirements in terms of diversity and interactivity due to their natural textures.In this paper,we propose a sketch-based generation method for generating diverse ceramic tile images based on a hand-drawn sketches using Generative Adversarial Network(GAN).The generated tile images can be tailored to meet the specific needs of the user for the tile textures.The proposed method consists of four steps.Firstly,a dataset of ceramic tile images with diverse distributions is created and then pre-trained based on GAN.Secondly,for each ceramic tile image in the dataset,the corresponding sketch image is generated and then the mapping relationship between the images is trained based on a sketch extraction network using ResNet Block and jump connection to improve the quality of the generated sketches.Thirdly,the sketch style is redefined according to the characteristics of the ceramic tile images and then double cross-domain adversarial loss functions are employed to guide the ceramic tile generation network for fitting in the direction of the sketch style and to improve the training speed.Finally,we apply hidden space perturbation and interpolation for further enriching the output textures style and satisfying the concept of“one style with multiple faces”.We conduct the training process of the proposed generation network on 2583 ceramic tile images dataset.To measure the generative diversity and quality,we use Frechet Inception Distance(FID)and Blind/Referenceless Image Spatial Quality Evaluator(BRISQUE)metrics.The experimental results prove that the proposed model greatly enhances the generation results of the ceramic tile images,with FID of 32.47 and BRISQUE of 28.44. 展开更多
关键词 Ceramic tile pattern design cross-domain learning deep learning GAN generative adversarial networks ResNet Block
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Synthesis of Ceramic Tiles Reinforced with Addition of Aluminum Particulate Waste
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作者 Carla Tainara de Oliveira Lima Rafael Pacheco Evangelista +2 位作者 Carlos Alberto França Junior Aldemiro JoséRocha Palma Mirtânia Antunes Leão 《Journal of Civil Engineering and Architecture》 2023年第10期484-492,共9页
Research conducted on ceramic materials has been investigating the incorporation of solid waste into their formulations,driven by the proper disposal of such waste and the reduction of negative environmental impacts.T... Research conducted on ceramic materials has been investigating the incorporation of solid waste into their formulations,driven by the proper disposal of such waste and the reduction of negative environmental impacts.This study analyzed the effects of adding aluminum powder residue to the physical properties of ceramic masses with the aim of obtaining new formulations for ceramic tiles.The aluminum residue and the standard mass for ceramic tile production were chemically characterized and homogenized to obtain new formulations with the incorporation of 4%,6%,8%,and 10%aluminum powder in the ceramic mass.The specimens were uniaxially pressed and sintered at a temperature of 1,200°C for 2 h,undergoing three different temperatures(100°C,400°C,and 650°C)for 30 min each.They were evaluated for WA(water absorption),RLq(linear shrinkage),SEM(scanning electron microscopy),and TRF(flexural strength)modulus.The results demonstrate that the addition of aluminum powder residue is feasible in the proposed formulations(4%,6%,8%,and 10%),as they enhance the mechanical properties of the ceramics compared to the formulation with 0%residue,at a sintering temperature of 1,200°C. 展开更多
关键词 CERAMICS ceramic tiles metallic waste aluminum waste.
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基于要素稠度的电子海图矢量瓦片组合构建方法
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作者 陈立家 曹原莱 +2 位作者 汪洋 黄立文 许毅 《重庆交通大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第8期34-42,共9页
为进一步提升基于WebGIS技术的电子海图在前端的加载效率,对海图矢量瓦片的划分方法进行深入研究。在考虑要素空间分布稠度的基础上,提出一种海图瓦片的组合格网划分方法。在四叉树划分过程中引入矢量瓦片数据阈值将其改造成非平衡四叉... 为进一步提升基于WebGIS技术的电子海图在前端的加载效率,对海图矢量瓦片的划分方法进行深入研究。在考虑要素空间分布稠度的基础上,提出一种海图瓦片的组合格网划分方法。在四叉树划分过程中引入矢量瓦片数据阈值将其改造成非平衡四叉树,作为瓦片划分的第1阶段,在瓦片划分至单瓦片最大数据量小于数据阈值后,通过融合变异系数的二叉树对瓦片进行第2阶段的划分。将组合格网法、原始均匀格网法和改进均匀格网法生成的矢量瓦片数据与试验结果进行对比。研究结果表明,在瓦片第3~第9层级范围内,相对于2种均匀格网法,基于要素稠度的组合格网法生成的矢量瓦片在同一层级的标准差更小,矢量要素在瓦片上的分布更加均衡,在同一视窗范围内,组合格网法生成的瓦片加载时间更短。 展开更多
关键词 航道工程 水路交通 WEB地理信息系统 矢量瓦片 组合格网法 电子海图 四叉树
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莆田地震台铟瓦棒伸缩仪故障分析及维修技术研究
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作者 陈伟 蔡佩蕊 +2 位作者 沈健健 吴劲柏 李毅伟 《科技创新与应用》 2024年第6期144-147,151,共5页
该文论述莆田地震台形变观测仪器SS-Y型铟瓦棒伸缩仪近几年来的故障,从电源、主机、传感器、线路故障等几个方面对故障进行整理、分类、统计。通过故障的表现形式分析故障原因,整理出不同故障曲线形态产生的原因。总结莆田地震台维修经... 该文论述莆田地震台形变观测仪器SS-Y型铟瓦棒伸缩仪近几年来的故障,从电源、主机、传感器、线路故障等几个方面对故障进行整理、分类、统计。通过故障的表现形式分析故障原因,整理出不同故障曲线形态产生的原因。总结莆田地震台维修经验,结合其他台站经验,针对不同故障给出维修方案,可为其他相关地震台站提供借鉴。 展开更多
关键词 形变观测仪器 SS-Y型铟瓦棒伸缩仪 故障维修 故障排查 传感器
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宽带片式有源阵列设计
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作者 向海生 臧永东 陈甘霖 《雷达与对抗》 2024年第1期31-35,52,共6页
针对多功能应用需求,提出一种宽带片式有源阵列的解决方案。有源阵列包含8个有源子阵,为了实现高集成、可扩展、低剖面设计,有源子阵采用三层片式架构,天线单元、T/R组件及延时多功能模块之间采用垂直互连。天线单元层、T/R组件层以及... 针对多功能应用需求,提出一种宽带片式有源阵列的解决方案。有源阵列包含8个有源子阵,为了实现高集成、可扩展、低剖面设计,有源子阵采用三层片式架构,天线单元、T/R组件及延时多功能模块之间采用垂直互连。天线单元层、T/R组件层以及延时多功能模块层均依托冷板进行装配,外部电源及控制通过延时多功能模块分配到T/R组件。测试结果表明:在瞬时带宽4 GHz、±45°扫描范围内,通过全时延补偿实现波束指向偏差接近1/10波束宽度。 展开更多
关键词 宽带 片式 有源阵列
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修复缺陷嫌疑区域的无监督磁瓦表面缺陷检测
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作者 唐善成 逯建辉 +2 位作者 张莹 金子成 赵安新 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2024年第4期718-728,共11页
磁瓦表面缺陷样本数量少,异常视觉特征分布发散,现有依赖目标特征的有监督检测方法不能有效检测未定义缺陷;磁瓦表面正常纹理呈非均匀且非周期性分布,使得经典重构网络难以准确地重构磁瓦表面正常特征,导致相关无监督检测方法性能低下.... 磁瓦表面缺陷样本数量少,异常视觉特征分布发散,现有依赖目标特征的有监督检测方法不能有效检测未定义缺陷;磁瓦表面正常纹理呈非均匀且非周期性分布,使得经典重构网络难以准确地重构磁瓦表面正常特征,导致相关无监督检测方法性能低下.为此,采用多头注意力增强的掩码图像修复网络(MIINet),长距离提取图像特征,捕捉全局信息,增强图像修复的能力;引入视觉显著性算法抑制磁瓦表面纹理信息和突显缺陷区域,以便二值化算法精准分割缺陷嫌疑区域;利用MIINet修复待检测图像缺陷嫌疑区域,选用修复前后图像的残差图像和结构相似性实现缺陷检测与缺陷判定.与经典无监督方法相比,修复缺陷嫌疑区域的表面缺陷检测方法的准确率提升了2.36%,F1值提升了1.62%. 展开更多
关键词 多头注意力 磁瓦表面缺陷检测 无监督学习 图像修复 视觉显著性
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陕西历史博物馆藏汉代“华仓”瓦当表面析出物的分析研究
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作者 荆海燕 郑丽珍 +1 位作者 白璐 蔡淋 《文物保护与考古科学》 北大核心 2024年第3期63-71,共9页
陶质文物表面析出物中含有机酸盐的现象在国内鲜有报道。本研究采用离子色谱仪(IC)、扫描电子显微镜-能谱仪(SEM-EDS)、X射线衍射仪(XRD)、傅里叶变化显微红外光谱仪(FTIR)、超景深显微镜(DM)对一件馆藏汉代“华仓”瓦当表面析出物进行... 陶质文物表面析出物中含有机酸盐的现象在国内鲜有报道。本研究采用离子色谱仪(IC)、扫描电子显微镜-能谱仪(SEM-EDS)、X射线衍射仪(XRD)、傅里叶变化显微红外光谱仪(FTIR)、超景深显微镜(DM)对一件馆藏汉代“华仓”瓦当表面析出物进行了表征和检测。结果表明,瓦当表面析出物主要由少量的二水硫酸钙和大量有机酸钙盐[Ca_(3)(CH_(3)COO)_(3)Cl(NO_(3))_(2)·6H_(2)O]组成,两种盐的形成与瓦当的制作过程、埋藏环境和灰尘有关,有机酸盐的形成还与馆藏环境中的乙酸有关。这种析出物不仅影响瓦当表面的真实文物信息,还会进一步腐蚀瓦当本体,建议从展柜中取出瓦当进行脱盐处理,存放在无酸的环境中。本检测分析为这件瓦当的保护修复方案的制定提供理论依据,也为类似文物样品的分析提供借鉴。 展开更多
关键词 瓦当 表面析出物 有机酸 分析检测技术
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建筑外墙砖饰面安全风险评估模型
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作者 杨霞 《施工技术(中英文)》 CAS 2024年第12期167-173,共7页
建筑外墙砖脱落事故频发,不仅破坏了建筑外观,更是危及居民人身安全。然而砖饰面损坏因素复杂,目前缺少可量化的风险评估模型。基于影响显著、易获取、可量化原则,选取距离上一次全面维修的年限、裂缝数量和立面空鼓面积比,作为外墙砖... 建筑外墙砖脱落事故频发,不仅破坏了建筑外观,更是危及居民人身安全。然而砖饰面损坏因素复杂,目前缺少可量化的风险评估模型。基于影响显著、易获取、可量化原则,选取距离上一次全面维修的年限、裂缝数量和立面空鼓面积比,作为外墙砖饰面安全风险评估的量化指标。通过对74个项目进行统计分析,综合运用信息量权重法和专家打分法,确定距离上一次全面维修的年限、裂缝数量和立面空鼓面积比的权重分别为0.20,0.41,0.39。最后通过项目验证,根据提出的安全风险计算模型,当安全风险分值达到40分时,外墙砖饰面发生高坠的风险概率较大。 展开更多
关键词 外墙砖饰面 脱落 评估 安全风险 信息量权重法 模型
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馆藏汉代瓦当表面可溶盐的化学组成分析
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作者 荆海燕 马芬 +2 位作者 郑丽珍 白璐 付文斌 《分析科学学报》 CAS CSCD 北大核心 2024年第2期244-248,共5页
采用离子色谱仪(IC),扫描电子显微镜-能谱仪(SEM-EDS),X射线衍射仪(XRD)和傅里叶变化显微红外光谱仪(FTIR)等现代分析仪器,对陕西历史博物馆馆藏的汉代瓦当表面可溶盐进行了鉴定,并分析了相关的化学组成。结果表明,瓦当表面可溶盐含有石... 采用离子色谱仪(IC),扫描电子显微镜-能谱仪(SEM-EDS),X射线衍射仪(XRD)和傅里叶变化显微红外光谱仪(FTIR)等现代分析仪器,对陕西历史博物馆馆藏的汉代瓦当表面可溶盐进行了鉴定,并分析了相关的化学组成。结果表明,瓦当表面可溶盐含有石膏(Ca SO_(4)·2H_(2)O)和有机酸钙盐[Ca_(3)(CH_(3)COO)_(3)Cl(NO_(3))_(2)·6H_(2)O]等成分。 展开更多
关键词 瓦当 可溶盐 扫描电子显微镜-能谱 X射线衍射 离子色谱
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一种搭载机械臂的瓷砖铺贴末端执行器的设计
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作者 陆亮 孙宁 王志鹏 《自动化应用》 2024年第1期123-126,共4页
针对手工铺贴瓷砖成本高、工作效率低、劳动强度大等问题,设计了一种搭载机械臂的瓷砖铺贴末端执行器。设计真空系统实现瓷砖吸放,设计惯性式激振器实现振动压实,利用激光测距传感器与边缘搜索方法检测定位。基于ROS开发了铺贴系统,实... 针对手工铺贴瓷砖成本高、工作效率低、劳动强度大等问题,设计了一种搭载机械臂的瓷砖铺贴末端执行器。设计真空系统实现瓷砖吸放,设计惯性式激振器实现振动压实,利用激光测距传感器与边缘搜索方法检测定位。基于ROS开发了铺贴系统,实现了搭载机械臂的瓷砖铺贴实验。结果表明,该装置能够实现300 mm×300 mm的瓷砖铺贴作业,重复定位标准偏差小于0.343 mm。 展开更多
关键词 机器人 瓷砖铺贴 末端执行器
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不刮瓦轴承的两个基础理论及其实例计算分析
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作者 江旭昌 《新世纪水泥导报》 CAS 2024年第2期4-10,I0013,共8页
不刮瓦轴承在我国水泥工业应用中存在两个问题:一是对其形成楔形间隙的必要性和重要性的认识模糊甚至存在疑虑;二是担心管磨机主轴承球面瓦的巴氏合金轴瓦会被压坏。为消除当前不少人对不刮瓦轴承技术的疑虑和担心,通过对不刮瓦轴承两... 不刮瓦轴承在我国水泥工业应用中存在两个问题:一是对其形成楔形间隙的必要性和重要性的认识模糊甚至存在疑虑;二是担心管磨机主轴承球面瓦的巴氏合金轴瓦会被压坏。为消除当前不少人对不刮瓦轴承技术的疑虑和担心,通过对不刮瓦轴承两个基础理论及其实例计算进行分析,得出结论:(1)不刮瓦轴承即无负荷时轴颈与轴瓦接触角φ=0的滑动轴承,是一种当前最先进的滑动轴承;(2)在管磨机中,水泥磨机主轴承轴瓦的负荷是最大的或者说是最重的,经过实例计算表明其安全系数n最小者竟然大于10,表明巴氏合金轴瓦是绝对不会被压坏的。 展开更多
关键词 回转窑 管磨机 滑动轴承 球形瓦 不刮瓦轴承 新型刮研法
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