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Anisotropy of Trabecular Bone from Ultra-Distal Radius Digital X-Ray Imaging: Effects on Bone Mineral Density and Age
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作者 Jian-Feng Chen 《Open Journal of Radiology》 2024年第1期14-23,共10页
Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions... Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions parallel and perpendicular to the forearm. Methodology: Data from more than two hundred subjects were studied retrospectively. A DXA (GE Lunar Prodigy) scan of the forearm was performed on each subject to measure the bone mineral density (BMD) value at the location of ultra-distal radius, and an X-ray digital image of the same forearm was taken on the same day. The values of trabecular bone score along the direction perpendicular to the forearm, TBS<sub>x</sub>, and along the direction parallel to the forearm, TBS<sub>y</sub>, were calculated respectively. The statistics of TBS<sub>x</sub> and TBS<sub>y</sub> were calculated, and the anisotropy of the trabecular bone, which was defined as the ratio of TBS<sub>y</sub> to TBS<sub>x</sub> and changed with subjects’ BMD and age, was reported and analyzed. Results: The results show that the correlation coefficient between TBS<sub>x</sub> and TBS<sub>y</sub> was 0.72 (p BMD and age was reported. The results showed that decreased trabecular bone anisotropy was associated with deceased BMD and increased age in the subject group. Conclusions: This study shows that decreased trabecular bone anisotropy was associated with decreased BMD and increased age. 展开更多
关键词 ANISOTROPY Trabecular Bone Score Bone Mineral Density Ultra-Distal Radius digital x-ray image
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Anisotropic creep behavior of soft-hard interbedded rock masses based on 3D printing and digital imaging correlation technology 被引量:1
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作者 TIAN Yun WU Fa-quan +5 位作者 TIAN Hong-ming LI Zhe SHU Xiao-yun HE Lin-kai HUANG Man CHEN Wei-zhong 《Journal of Mountain Science》 SCIE CSCD 2023年第4期1147-1158,共12页
Three-dimensional(3D)printing technology is increasingly used in experimental research of geotechnical engineering.Compared to other materials,3D layer-by-layer printing specimens are extremely similar to the inherent... Three-dimensional(3D)printing technology is increasingly used in experimental research of geotechnical engineering.Compared to other materials,3D layer-by-layer printing specimens are extremely similar to the inherent properties of natural layered rock masses.In this paper,soft-hard interbedded rock masses with different dip angles were prepared based on 3D printing(3DP)sand core technology.Uniaxial compression creep tests were conducted to investigate its anisotropic creep behavior based on digital imaging correlation(DIC)technology.The results show that the anisotropic creep behavior of the 3DP soft-hard interbedded rock mass is mainly affected by the dip angles of the weak interlayer when the stress is at low levels.As the stress level increases,the effect of creep stress on its creep anisotropy increases significantly,and the dip angle is no longer the main factor.The minimum value of the long-term strength and creep failure strength always appears in the weak interlayer within 30°–60°,which explains why the failure of the layered rock mass is controlled by the weak interlayer and generally emerges at 45°.The tests results are verified by comparing with theoretical and other published studies.The feasibility of the 3DP soft-hard interbedded rock mass provides broad prospects and application values for 3DP technology in future experimental research. 展开更多
关键词 3D printing Soft-hard interbedded rock mass digital imaging correlation technology Weak interlayer Anisotropic creep
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Imaging Analysis of Trabecular Bone Texture Based on the Initial Slope of Variogram of Ultra-Distal Radius Digital X-Ray Imaging: Effects on Bone Mineral Density and Age
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作者 Jianfeng Chen Qifeng Ying 《Open Journal of Radiology》 2022年第3期78-85,共8页
Background: When applied to trabecular bone X-ray images, a method for analyzing trabecular bone texture based on the initial slope of variogram (ISV) was used to assess the trabecular bone health. Methodology: Data f... Background: When applied to trabecular bone X-ray images, a method for analyzing trabecular bone texture based on the initial slope of variogram (ISV) was used to assess the trabecular bone health. Methodology: Data from more than two hundred subjects were retrospectively studied. For each subject, a DXA (GE Lunar Prodigy) scan of the forearm was performed, and bone mineral density (BMD) value was measured at the location of ultra-distal radius, X-ray digital image of the same forearm was taken on the same day, and ISV value over the same location of ultra-distal radius was calculated. Pearson’s correlation coefficients were calculated to examine the correlation between BMD and ISV of the trabecular bones located at the same ultra-distal radius. ISV values changed with subjects’ age were also reported. Results: The results show that ISV value was highly correlated with the DXA-measured BMD of the same trabecular bone located at the ultra-distal radius. The correlation coefficient between ISV and BMD with the 95% confident was 0.79 ± 0.09. They also demonstrated that the age-related changes in trabecular bone health and differentiated age patterns in males and females, respectively. The results showed that the decrease in BMD was accompanied by a decrease in the initial slope of variogram (ISV). Conclusions: This study suggests that ISV might be used to quantitatively evaluate trabecular health for osteoporosis and bone disease diagnosis. 展开更多
关键词 Trabecular Bone Texture digital x-ray image Bone Mineral Density Ultra-Distal Radius Initial Slope of Variogram
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The First International Digital Printing and Image Technology Exhibition & The Sixth International Exhibition of Quick Printing Equipment & Technology
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《印刷工业》 2008年第2期118-119,共2页
Time: Sept.4-6, 2008Venue: Shenzhen Convention & Exhibition CenterSponsor: Printing and Printing Equipment Industries Association of China (PEIAC)Organizers: The Exhibition Department of
关键词 technology The First International digital Printing and image technology Exhibition
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A cadaveric breast cancer tissue phantom for phase-contrast X-ray imaging applications
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作者 Cody C.Rounds Chengyue Li +2 位作者 Wei Zhou Kenneth M.Tichauer Jovan G.Brankov 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第5期427-432,共6页
Background:As mammography X-ray imaging technologies advance and provide elevated contrast in soft tissues,a need has developed for reliable imaging phantoms for use in system design and component calibration.In advan... Background:As mammography X-ray imaging technologies advance and provide elevated contrast in soft tissues,a need has developed for reliable imaging phantoms for use in system design and component calibration.In advanced imaging modalities such as refraction-based methods,it is critical that developed phantoms capture the biological details seen in clinical precancerous and cancerous cases while minimizing artifacts that may be caused due to phantom production.This work presents the fabrication of a breast tissue imaging phantom from cadaveric breast tissue suitable for use in both transmission and refraction-enhanced imaging systems.Methods:Human cancer cell tumors were grown orthotopically in nude athymic mice and implanted into the fixed tissue while maintaining the native tumor/adipose tissue interface.Results:The resulting human–murine tissue hybrid phantom was mounted on a clear acrylic housing for absorption and refraction X-ray imaging.Digital breast tomosynthesis was also performed.Conclusion:Both attenuation-based imaging and refraction-based imaging of the phantom are presented to confirm the suitability of this phantom's use in both imaging modalities. 展开更多
关键词 breast tumors digital mammography imaging phantoms orthotopic animal models phasecontrast x-ray imaging
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Enhancing transjugular intrahepatic portosystemic shunt procedure efficiency with digital subtraction angiography image overlay technology in esophagogastric variceal bleeding
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作者 Xiao-Yan Li Yao Li +3 位作者 Wen-Qiang Li Shuai Ju Zhi-Hui Dong Jian-Jun Luo 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第9期2870-2877,共8页
BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS)is a pivotal intervention for managing esophagogastric variceal bleeding in patients with chronic hepatic schistosomiasis.AIM To evaluate the efficacy of d... BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS)is a pivotal intervention for managing esophagogastric variceal bleeding in patients with chronic hepatic schistosomiasis.AIM To evaluate the efficacy of digital subtraction angiography image overlay tech-nology(DIT)in guiding the TIPS procedure.METHODS We conducted a retrospective analysis of patients who underwent TIPS at our hospital,comparing outcomes between an ultrasound-guided group and a DIT-guided group.Our analysis focused on the duration of the portosystemic shunt puncture,the number of punctures needed,the total surgical time,and various clinical indicators related to the surgery.RESULTS The study included 52 patients with esophagogastric varices due to chronic hepatic schistosomiasis.Results demonstrated that the DIT-guided group expe-rienced significantly shorter puncture times(P<0.001)and surgical durations(P=0.022)compared to the ultrasound-guided group.Additionally,postoperative assessments showed significant reductions in aspartate aminotransferase,B-type natriuretic peptide,and portal vein pressure in both groups.Notably,the DIT-guided group also showed significant reductions in total bilirubin(P=0.001)and alanine aminotransferase(P=0.023).CONCLUSION The use of DIT for guiding TIPS procedures highlights its potential to enhance procedural efficiency and reduce surgical times in the treatment of esophagogastric variceal bleeding in patients with chronic hepatic schistoso-miasis. 展开更多
关键词 Portal hypertension digital subtraction angiography image overlay technology Hepatic artery labeling Transjugular intrahepatic portosystemic shunt
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Fine Characterization and Analysis of Drying Strain of the ELM Board via DIC Technology
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作者 Yuanchu Liu Xiaodong Zhu +5 位作者 Zhengmin Jin Yingying Liu Qingjian Wei Bonan Liang Yingchun Cai Jingyao Zhao 《Journal of Renewable Materials》 SCIE EI 2023年第2期567-580,共14页
In this paper,the occurrence and development mechanism of strain on the cross-section during the wood drying is explored.Therefore,strain regularity on the cross-section of 50 mm thickness elm(Ulmus rubra)board at the... In this paper,the occurrence and development mechanism of strain on the cross-section during the wood drying is explored.Therefore,strain regularity on the cross-section of 50 mm thickness elm(Ulmus rubra)board at the temperature of 40℃and 80℃is detected via digital image correlation technology.Hence,the difference between tangential and radial strain at surface and core layers was denoted.The results showed that strain distribution in the width direction of the board is uneven.Moreover,a large drying shrinkage strain occurs at the near-core layer,while the maximum strain difference reaches 4.08%.Hence,the surface of the board is cracked along the thickness direction.The radial strain of the board is higher than the tangential strain in the early stage of drying,while these strains are reversed in the later stage of drying.The temperature is related to the difference between the tangential and radial strains of the elm board.These differences at the core layer are larger than those of the surface layer.The conducted research results provide a theoretical basis for process optimization. 展开更多
关键词 digital image correlation technology drying strain fine characterization moisture content distribution
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Rapid digitalization and panoramic evaluation of weld X-ray film
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作者 闫志鸿 宋永伦 +1 位作者 王彬 李元香 《China Welding》 EI CAS 2011年第1期49-53,共5页
The computer evaluation of weld X-ray film is an attractive technique for weld seam NDT ( nondestructive testing). To achieve this target, digitalization of film is the first step and automatic defect identification... The computer evaluation of weld X-ray film is an attractive technique for weld seam NDT ( nondestructive testing). To achieve this target, digitalization of film is the first step and automatic defect identification is another key technique. In this paper, a weld X-ray film digitalizing system has been established with linear array CCD and highlight LED light source. Its space resolution can reach 0. 04 mm/pixel and scanning speed can reach 100 mm/s for an industrial film. The transfer function curves of the system have been measured and the results indicate that its image gray resolution can reach 88 G/D at 4. 5D, and its dynamic range can be wider than 2. OD. In order to facilitate the evaluation of large welded structure, a panoramic evaluation algorithm is developed also. The algorithm includes image matching, image fusion and panoramic evaluation of the long linked film image. 展开更多
关键词 weld x-ray film rapid digitalization image processing panoramic evaluation
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The Digital Mapping of Ukrainian Soils on the Base of High Resolution Space Images
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作者 Stanislav Truskavetsky 《Journal of Geodesy and Geomatics Engineering》 2015年第1期59-62,共4页
关键词 测绘学 测绘工程 理论 方法
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Hydrophobic long-chain two-dimensional perovskite scintillators for underwater X-ray imaging
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作者 Jin-Xiao Zheng Zi-An Zhou +6 位作者 Tiao Feng Hui Li Cheng-Hua Sun NüWang Yang Tian Yong Zhao Shu-Yun Zhou 《Rare Metals》 SCIE EI CAS CSCD 2024年第1期175-185,共11页
The underwater X-ray imaging technology development is significant to subaqueous target reconnaissance/detection/identification, subfluvial archaeology,submerged resource exploration, etc. As the core of X-ray imaging... The underwater X-ray imaging technology development is significant to subaqueous target reconnaissance/detection/identification, subfluvial archaeology,submerged resource exploration, etc. As the core of X-ray imaging detection, the scintillator has been plagued by inherent moisture absorption and decomposition, and strict requirements for seamless packaging and waterproofing.Here, we designed a manganese-doped two-dimensional(2D) perovskite scintillator modified by hydrophobic longchain organic amine through the combination of component and doping engineering. The modified perovskites show high water repellency that can be used as an underwater X-ray scintillator. X-ray images of aquatic organisms or other objects with a high spatial resolution of10 lp·mm^(-1) at a big view field(32 mm × 32 mm) were obtained by scintillation screen. This hydrophobic perovskite scintillator based on molecular design is of great promise in underwater X-ray nondestructive testing technology development. 展开更多
关键词 Two-dimensional perovskite HYDROPHOBIC SCINTILLATORS Underwater x-ray imaging Underwater nondestructive testing technology
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An Improved Neural Network Method for Forearm Bone Imaging Segmentation
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作者 Songzheng Huang Jianfeng Chen 《Open Journal of Radiology》 2022年第4期176-188,共13页
In this paper, we propose several improved neural networks and training strategy using data augmentation to segment human radius accurately and efficiently. This method can provide pixel-level segmentation accuracy th... In this paper, we propose several improved neural networks and training strategy using data augmentation to segment human radius accurately and efficiently. This method can provide pixel-level segmentation accuracy through the low-level features of the neural network, and automatically distinguish the classification of radius. The versatility and applicability can be effectively improved by learning and training digital X-ray images obtained from digital X-ray imaging systems of different manufacturers. 展开更多
关键词 Human Radius digital x-ray image U-shaped Unet Neural Network SEGMENTATION
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基于声发射和DIC的金属材料氢脆性能测试实验
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作者 蒋鹏 吴爽 +2 位作者 黄洋 邢雷 张丰运 《实验技术与管理》 CAS 北大核心 2024年第6期20-27,共8页
该实验针对天然气掺氢管道混输过程中产生的临氢金属氢脆问题,以X80管线钢为对象,采用声发射与数字图像相关(DIC)技术相结合的方法实现氢脆性能的动态测试。实验设计为对材料进行充氢后拉伸,采用电化学充氢法充氢,并设置4种不同充氢时... 该实验针对天然气掺氢管道混输过程中产生的临氢金属氢脆问题,以X80管线钢为对象,采用声发射与数字图像相关(DIC)技术相结合的方法实现氢脆性能的动态测试。实验设计为对材料进行充氢后拉伸,采用电化学充氢法充氢,并设置4种不同充氢时间。拉伸过程中通过DIC技术测量并计算静态氢脆性能参数和氢脆敏感系数,同时利用等效应变云图和声发射计数峰值时域分布的变化规律作为氢脆性能的动态参量,进而建立一套完整的金属氢脆性能动态测试系统。该实验适合作为学生研究型教学实验,有助于培养学生的科研能力和创新意识。 展开更多
关键词 电化学充氢 声发射监测 数字图像相关技术 实验设计
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数字医学3D成像技术与传统2D成像技术在儿童腹部实体肿瘤术前医患沟通中的应用价值
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作者 吴昌耀 李强辉 +5 位作者 周维模 龙雪峰 许林 全军利 农振良 梁仕兰 《临床医学研究与实践》 2024年第23期34-37,共4页
目的比较数字医学3D成像技术与传统2D成像技术在儿童腹部实体肿瘤术前医患沟通中的应用价值。方法选取2018年1月至2022年1月广西壮族自治区贵港市人民医院小儿外科收治的80例腹部实体肿瘤患儿为研究对象,随机将其分为试验组和对照组,各4... 目的比较数字医学3D成像技术与传统2D成像技术在儿童腹部实体肿瘤术前医患沟通中的应用价值。方法选取2018年1月至2022年1月广西壮族自治区贵港市人民医院小儿外科收治的80例腹部实体肿瘤患儿为研究对象,随机将其分为试验组和对照组,各40例。试验组使用数字医学3D成像技术进行术前医患沟通,对照组使用传统2D成像技术进行术前医患沟通。比较两组患儿家属的焦虑自评量表(SAS)、抑郁自评量表(SDS)评分及满意度。结果沟通后,两组患儿家属的SAS和SDS评分均降低,且试验组低于对照组,差异具有统计学意义(P<0.05)。试验组患儿家属的满意度明显高于对照组,差异具有统计学意义(P<0.05)。结论数字医学3D成像技术在儿童腹部实体肿瘤术前医患沟通中发挥了积极作用,可减轻患儿家属术前焦虑及抑郁情绪,提高了对医疗服务的满意度,增强了患儿家属对医疗过程的依从性,值得在临床中推广。 展开更多
关键词 数字医学3D成像技术 儿童 腹部实体肿瘤 术前医患沟通
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城市更新背景下公共艺术塑造城市形象的创新策略研究
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作者 王峰 高超 《工业工程设计》 2024年第3期103-110,共8页
在中国当前的城市更新背景下,对城市形象的塑造是城市未来发展的主要方向,也是国家文化战略的重要内容。公共艺术与城市形象之间有着十分密切的联系,是塑造城市形象的重要手段。在当前的数字化时代背景下,把数字化技术介入公共艺术之中... 在中国当前的城市更新背景下,对城市形象的塑造是城市未来发展的主要方向,也是国家文化战略的重要内容。公共艺术与城市形象之间有着十分密切的联系,是塑造城市形象的重要手段。在当前的数字化时代背景下,把数字化技术介入公共艺术之中用以塑造城市形象已成为公共艺术创作者的普遍选择。立足于中国当前的城市更新背景,首先对公共艺术与城市形象之间的关系进行分析,然后在此基础上探讨公共艺术以塑造城市形象的创新途径和方式。通过研究表明,在中国当前的城市更新背景下,数字化技术的介入是公共艺术塑造城市形象的重要创新途径,在数字化技术介入下所创作的数字化公共艺术为公众营造多元化、多维度的体验感受是公共艺术塑造城市形象的重要创新方式。 展开更多
关键词 城市更新 城市形象 公共艺术 数字化技术
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定向断裂控制爆破下层理页岩的致裂机理
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作者 杨国梁 毕京九 +3 位作者 董智文 赵桐德 赵建宇 赵康朴 《爆炸与冲击》 EI CAS CSCD 北大核心 2024年第6期1-15,共15页
为探究定向断裂控制爆破下层理页岩的爆破致裂机理,采用切缝药包,对四种切缝角度下的页岩立方体试件进行爆破试验,采用数字图像相关技术(DIC)对页岩试件表面应变场的演化过程进行监测,分析了微裂纹孕育至宏观裂纹贯通的内在机理,并基于... 为探究定向断裂控制爆破下层理页岩的爆破致裂机理,采用切缝药包,对四种切缝角度下的页岩立方体试件进行爆破试验,采用数字图像相关技术(DIC)对页岩试件表面应变场的演化过程进行监测,分析了微裂纹孕育至宏观裂纹贯通的内在机理,并基于盒维数理论计算了不同切缝角度下页岩试件表面裂纹的分形维数,采用Matlab软件对爆后块度的筛分方法进行了编程分析,开发了全自动的粒径分析程序,实现了粒径圈定的可视化。试验结果表明:试件在不同比例爆距内的裂纹总密度与比例爆距之间存在负相关的幂函数关系,切缝方向与层理弱面的夹角对微观损伤区域出现的位置影响显著,当层理弱面与切缝方向平行时,损伤区域多集中于层理弱面处,对宏观裂纹的扩展路径影响显著,易于形成单一裂纹;层理弱面处的能量泄漏是造成页岩爆破破碎效果较差的重要因素,当切缝方向与层理弱面一致时,试件爆后的大块占比较高,爆后块度的分形维数平均值在各组间最低,仅为0.7843,而当切缝方向与层理面垂直时,试件的爆后块度分布较为均匀,爆后块度的分形维数平均值达到了2.5233,爆破破碎效果相对较好。 展开更多
关键词 页岩 爆破 裂隙场 数字图像相关技术 块度筛分程序 分形维数
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数字影像文体演变:创新与挑战
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作者 李岩 《民族艺术研究》 2024年第3期31-39,共9页
随着技术与文化相互作用的深入,数字影像文体的演变展现出与技术物的共轭关系。这种关系的建立是技术与社会结构、文化形式相互作用的结果。其再生产机制强调了“模因—算法”驱动与“新技术形态”驱动两个维度。同时,数字影像文体的演... 随着技术与文化相互作用的深入,数字影像文体的演变展现出与技术物的共轭关系。这种关系的建立是技术与社会结构、文化形式相互作用的结果。其再生产机制强调了“模因—算法”驱动与“新技术形态”驱动两个维度。同时,数字影像文体的演变还是社会结构变动、劳动和生产关系重塑,以及文化形态变革的一部分,其以具体形态重新定义了权力结构和人类认知的框架。此外,数字影像文体也是马克思“通用智力”理论的现实案例,其演变进一步阐述了数字技术如何在全球范围内重新配置信息和行使权力,揭示了技术进步如何引领影像文体革命,并预示了未来社会文化动态的可能方向。 展开更多
关键词 数字影像文体 技术美学 社会变革 媒介考古
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ECC疲劳损伤规律及微观结构研究
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作者 蔡靖 刘汉磊 +2 位作者 霍海峰 支雁飞 任彦龙 《中国民航大学学报》 CAS 2024年第1期59-64,共6页
为研究工程水泥基复合材料(ECC,engineered cementitious composites)的疲劳规律并探究其损伤原因,利用疲劳试验机对ECC试件进行单轴拉伸循环加载试验,分析其疲劳规律及损伤界面微观形态。研究结果表明:ECC试件破坏规律与其累积轴向应... 为研究工程水泥基复合材料(ECC,engineered cementitious composites)的疲劳规律并探究其损伤原因,利用疲劳试验机对ECC试件进行单轴拉伸循环加载试验,分析其疲劳规律及损伤界面微观形态。研究结果表明:ECC试件破坏规律与其累积轴向应变速率有关,在加载初始阶段,累积轴向应变会随着循环荷载作用次数增加而明显增大,随后进入稳定变形阶段;进一步加载将导致累积轴向应变快速增长,并最终导致试件断裂破坏;ECC的裂纹宽度发展呈现出中间低、两端高的趋势;ECC试件在循环荷载过程中初次开裂后,不会迅速进入破坏阶段,是因为纤维仍然具有抗拉能力,可继续承受循环荷载加载;通过对纤维-基体界面的微观分析发现,纤维与基体结合较好,可整体耗散能量,为ECC具有高疲劳性能的主要原因。 展开更多
关键词 水泥基复合材料 微观结构 轴向拉伸疲劳 数字成像技术
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“任务链+研学支架”教学模式的建构——新工科视角下“遥感数字图像处理”课教学改革
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作者 江振蓝 秦艳芳 +1 位作者 林木生 陈思明 《闽江学院学报》 2024年第1期101-108,共8页
目前,传统教学在内容的系统性、认知活动高阶性、价值引领实效性、促学效果等方面存在着较严重的问题,为此,“遥感数字图像处理”课程基于新工科教学理念,以遥感技术的综合应用情境重构课程体系,开启“任务链+研学支架”教学模式,加强... 目前,传统教学在内容的系统性、认知活动高阶性、价值引领实效性、促学效果等方面存在着较严重的问题,为此,“遥感数字图像处理”课程基于新工科教学理念,以遥感技术的综合应用情境重构课程体系,开启“任务链+研学支架”教学模式,加强培养学生遥感应用能力和创新能力,以遥感技术服务社会需求为育人路径。新模式的构建,实现了应用与研学互动、研学与研教并举、育人与育才同构的效果,对同类型新工科课程具有借鉴意义。 展开更多
关键词 “遥感数字图像处理”课程 “任务链+研学支架”教学模式 遥感技术 “新工科”教育理念
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口腔临床诊疗中数字牙片影像技术的应用价值
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作者 马玉新 臧德鑫 《中国医药指南》 2024年第12期89-91,共3页
目的探讨口腔临床诊疗中数字牙片影像技术的应用价值。方法选择2022年1月至2023年5月期间在本院口腔科就诊且需要拔牙治疗的50例正畸患者作为研究对象。患者在治疗前,完成数字化牙片摄影和传统牙片摄影。记录投照上、下颌牙齿X线倾斜的... 目的探讨口腔临床诊疗中数字牙片影像技术的应用价值。方法选择2022年1月至2023年5月期间在本院口腔科就诊且需要拔牙治疗的50例正畸患者作为研究对象。患者在治疗前,完成数字化牙片摄影和传统牙片摄影。记录投照上、下颌牙齿X线倾斜的垂直平均角度,并统计牙齿根尖片的曝光时间,对比两种摄影技术对牙齿长度的测量结果。结果传统牙片摄影时,上颌和下颌切牙位、单尖牙、双尖牙位、第一磨牙位、第二及三磨牙位(足侧倾斜)选择投射角度低于数字化牙片摄影(P<0.05)。数字化牙片摄影投照上颌和下颌切牙位、单尖牙位、双尖牙位、第三磨牙位及第一、二磨牙位牙齿根尖片的曝光时间低于传统牙片摄影(P<0.05)。数字化牙片摄影对待拔除牙齿单根、双根颊和双根腭测量结果与游标卡尺测量结果相比,差异无统计学意义(P>0.05);传统牙片摄影对待拔除牙齿单根、双根颊和双根腭测量结果低于游标卡尺测量结果,差异具有统计学意义(P<0.05);以游标卡尺测量结果为依据,数字化牙片摄影和传统牙片摄影对待拔除牙齿单根、双根颊和双根腭测量结果相比,差异具有统计学意义(P<0.05)。结论数字牙片影像技术投照条件宽容度相对较大,投射时曝光时间短,对牙齿根尖的测量准确度较高,便于细致观察牙齿,应用于口腔临床诊疗的价值较高。 展开更多
关键词 口腔 临床诊疗 数字牙片影像技术 投射角度 根尖长度 应用价值
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数字图像相关技术测量位移的算法和试验研究
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作者 张子真 《城市勘测》 2024年第1期156-160,164,共6页
基于空间几何知识,通过建立空间直角坐标系、确定位移在Π平面上的投影,以及反推实际位移向量等三步,推导出数字图像监测系统在二维平面内的位移测量数学原理。然后选择不同场景展开现场应用,通过分析人工与自动化监测成果数据,发现光... 基于空间几何知识,通过建立空间直角坐标系、确定位移在Π平面上的投影,以及反推实际位移向量等三步,推导出数字图像监测系统在二维平面内的位移测量数学原理。然后选择不同场景展开现场应用,通过分析人工与自动化监测成果数据,发现光照强度变化、温度变化和距离增加,均会降低监测精度。 展开更多
关键词 空间几何 数字图像相关技术 精度
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