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浅谈flash中数字变化控制动画变化的多种解决方法
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作者 伍守意 《电脑知识与技术(过刊)》 2011年第3X期1900-1901,共2页
该文介绍了如何通过flash的代码来实现数字变化与动画变化的连接,并给出了两个实例来分别讲述了实现这种变化的两种方法。
关键词 数字变化 动画变化 连接 逐帧动画 IF语句
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数字变化规律
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作者 季林远 《新课程实验教材小一数学教案设计合订本》 2003年第1期85-86,共2页
关键词 数字变化 变化规律 小学 教学 数学 数字排列
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针对土地覆盖变化的多时相遥感探测方法 被引量:13
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作者 周斌 《矿物学报》 CAS CSCD 北大核心 2000年第2期165-171,共7页
本文对土地覆盖的遥感变化探测方法的前处理、多时相融合分析、阈值划分和精度评价等方面进行了回顾 ,并讨论了各种算法和波段组合在不同的应用中所具有的效果 。
关键词 多光谱遥感 土地覆盖 数字变化探测 数据融合
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从数字看草原 被引量:5
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作者 刘加文 《草原与草坪》 CAS 2008年第4期77-79,共3页
中国是一个草原资源大国。草原是国土的主体、生态安全的保障、动植物资源的宝库、中华民族经济发展的重要家园,也是我国畜牧业的基本载体和大有作为的"粮库"。但同时也要看到,当前我国草原的承载压力已不堪重负,草原保护建... 中国是一个草原资源大国。草原是国土的主体、生态安全的保障、动植物资源的宝库、中华民族经济发展的重要家园,也是我国畜牧业的基本载体和大有作为的"粮库"。但同时也要看到,当前我国草原的承载压力已不堪重负,草原保护建设落后,基础设施相当薄弱,草原地区已成为我国新农村建设和小康社会发展的难点地区。我们必须充分认识草原的战略地位和作用,加强保护、加快建设,促进草原可持续发展。 展开更多
关键词 草原 数字变化 重要性
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浅谈flash中如何解决数字控制元件动画的精确度问题
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作者 潘彪 黄颖杰 《电脑知识与技术(过刊)》 2010年第33期9422-9424,共3页
该文介绍了如何通过flash的代码来解决数字控制元件动画的精确度问题,并给出了两个实例来分别讲述了如何解决这个问题。
关键词 数字变化 动画变化 IF语句 精确度
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自动化技术在数字化变电站的应用 被引量:3
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作者 石磊 《无线互联科技》 2013年第5期191-191,共1页
自动化技术在数字化变电站中的应用,对于实现变电站资源共享,提高电网运行稳定性等方面具有重要意义。对数字化变电站的结构进行了分析,同时介绍了数字化变电站的特征,重点阐述了自动化技术在数字化变化站中应用的优势。
关键词 自动化技术 数字变化 应用
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生猪价格变动的规律、原因及对策——基于山东烟台8县市2003-2021年生猪数据 被引量:2
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作者 孙艳 朱应民 +3 位作者 李渤南 由佳 孔凡虎 许海军 《中国猪业》 2021年第4期13-16,21,共5页
猪肉是中国饮食文化中重要的动物性食材之一,因而生猪产业的发展变化及猪肉的价格备受消费者的关注。本文对烟台市8个县(市、区)2003—2021年的生猪价格等信息进行分析,对其变化、成因及后期对策进行论述,为把握生猪生产形势,调整生产结... 猪肉是中国饮食文化中重要的动物性食材之一,因而生猪产业的发展变化及猪肉的价格备受消费者的关注。本文对烟台市8个县(市、区)2003—2021年的生猪价格等信息进行分析,对其变化、成因及后期对策进行论述,为把握生猪生产形势,调整生产结构,稳定养殖收益提供一定的数据参考。 展开更多
关键词 生猪养殖 数字变化 价格 养殖对策
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Informational digital diagrams applied to predict spring wind,snow,and sandstorms
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作者 李明娟 赵奎锋 《Applied Geophysics》 SCIE CSCD 2008年第2期149-155,共7页
Using informational digital diagrams, we analyzed the snow event that occurred on Feb 26, 2006 and the sandstorm on Apr 11, 2006 in Xi'an. Results indicate that, under similar weather circumstances, different events ... Using informational digital diagrams, we analyzed the snow event that occurred on Feb 26, 2006 and the sandstorm on Apr 11, 2006 in Xi'an. Results indicate that, under similar weather circumstances, different events evidently exhibit unique vertical structure features. Informational digital diagrams provide a method for transitional weather prediction, a problem for present extrapolative analysis system. 展开更多
关键词 Transition Informational Digital Diagrams SANDSTORM
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一种基于欠采样的高频正弦信号初相测量方法
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作者 姚锡钦 郑胜峰 《浙江工贸职业技术学院学报》 2021年第3期52-55,63,共5页
本文研究了一种基于最大公因子频率的欠采样特高频率初相测量方法,介绍了两个正弦信号之间的频率关系并详细分析了其特点,并将此频率之间的相位关系应用于高频信号的采集中,可以在不满足乃奎斯特采样定理的条件下,用低于被测信号频率的... 本文研究了一种基于最大公因子频率的欠采样特高频率初相测量方法,介绍了两个正弦信号之间的频率关系并详细分析了其特点,并将此频率之间的相位关系应用于高频信号的采集中,可以在不满足乃奎斯特采样定理的条件下,用低于被测信号频率的信号对被测高频信号进行同步采样,结合数字正交变化技术和多重互相关技术,实现了对高频正弦信号的初相的准确测量,实验结果表明本文方法实现了对高频信号的初相的准确测量,尤其在低信噪比下也有较高的测量准确度. 展开更多
关键词 欠采样 初相 数字正交变化
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Association between TLR7 copy number variations and hepatitis B virus infection outcome in Chinese 被引量:2
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作者 Fang Li Xu Li +2 位作者 Gui-Zhou Zou Yu-Feng Gao Jun Ye 《World Journal of Gastroenterology》 SCIE CAS 2017年第9期1602-1607,共6页
AIM To explore whether copy number variations (CNVs) of toll-like receptor 7 (TLR7) are associated with susceptibility to chronic hepatitis B virus (HBV) infection. METHODS This study included 623 patients (495 males ... AIM To explore whether copy number variations (CNVs) of toll-like receptor 7 (TLR7) are associated with susceptibility to chronic hepatitis B virus (HBV) infection. METHODS This study included 623 patients (495 males and 128 females) with chronic hepatitis B virus infection (CHB) and 300 patients (135 females and 165 males) with acute hepatitis B virus infection (AHB) as controls. All CHB patients were further categorized according to disease progression after HBV infection (CHB, liver cirrhosis, or hepatocellular carcinoma). Copy numbers of the TLR7 gene were measured using the AccuCopy method chi(2) tests were used to evaluate the association between TLR7 CNVs and infection type. P values, odds ratios, and 95% confidence intervals (CIs) were used to estimate the effects of risk. RESULTS Among male patients, there were significant differences between the AHB group and CHB group in the distribution of TLR7 CNVs. Low copy numberof TLR7 was significantly associated with chronic HBV infection (OR = 0.329, 95% CI: 0.229-0.473, P > 0.001). Difference in TLR7 copy number was also found between AHB and CHB female patients, with low copy number again associated with an increased risk of chronic HBV infection (OR = 0.292, 95% CI: 0.173- 0.492, P < 0.001). However, there were no significant differences in TLR7 copy number among the three types of chronic HBV infection (CHB, liver cirrhosis, or hepatocellular carcinoma). In addition, there was no association between TLR7 copy number and titer of the HBV e antigen. CONCLUSION Low TLR7 copy number is a risk factor for chronic HBV infection but is not associated with later stages of disease progression. 展开更多
关键词 Toll-like receptor 7 Hepatitis B virus Copy number variations Gene susceptibility
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A numerical study on seasonal variations of the Taiwan Warm Current 被引量:5
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作者 白学志 胡敦欣 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第3期278-285,共8页
Princeton Ocean Model (POM) is employed to investigate the Taiwan Warm Current (TWC) and its seasonal variations. Results show that the TWC exhibits pronounced seasonal variations in its sources,strength and flow patt... Princeton Ocean Model (POM) is employed to investigate the Taiwan Warm Current (TWC) and its seasonal variations. Results show that the TWC exhibits pronounced seasonal variations in its sources,strength and flow patterns. In summer, the TWC flows northeast in straight way and reaches around 32°N; it comes mainly from the Taiwan Strait, while its lower part is from the shelf-intrusion of the Kuroshio subsurface water (KSSW). In winter, coming mainly from the shelf-intrusion of the Kuroshio northeast of Taiwan, the TWC flows northward in a winding way and reaches up around 30°N. The Kuroshio intrusion also has distinct seasonal patterns. The shelf-intrusion of KSSW by upwelling is almost the same in four seasons with a little difference in strength; it is a persistent source of the TWC. However, Kuroshio surface water (KSW) can not intrude onto the shelf in summer, while in winter the intrusion of KSW always occurs. Additional experiments were conducted to examine effects of winds and transport through the Taiwan Strait on the TWC. In winter, northerly winds enhance the shelf-intrusion of the Kuroshio and spread northward, but hamper the northward inflow from the Taiwan Strait. In summer, the effect of the winds is confined in the surface layer, and less obvious than that of winter. Transport through the Taiwan Strait influences the TWC significantly. With the Taiwan Strait closed in the simulation, the TWC would be dramatically weakened. 展开更多
关键词 Taiwan Warm Current Kuroshio intrusion seasonal variations numerical simulation
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Compensation for diffusion loss of sound wave in sonar system
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作者 徐琳 王润田 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期54-58,共5页
Sound pressure amplitude will be attenuated with propagation distance in a certain rule when sound wave is propagated in shallow sea.When processing the attenuated signal,time-variant gain circuit is usually used to c... Sound pressure amplitude will be attenuated with propagation distance in a certain rule when sound wave is propagated in shallow sea.When processing the attenuated signal,time-variant gain circuit is usually used to compensate its diffusion loss.In this paper,spherical diffusion loss is compensated by digital potentiometer and operational circuit and further investigation is also made on compensation of cylindrical diffusion loss and transition from spherical diffusion loss to cylindrical diffusion loss.Finally,a new compensation model is proposed for unknown propagation loss for the purpose of adjusting the dynamic range of signal to meet the requirement of A/D conversion. 展开更多
关键词 diffusion loss time-variant gain DIGITIZATION sonar system
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Equilibrium morphology of gas–liquid Janus droplets: A numerical analysis of buoyancy effect 被引量:1
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作者 Shaobin Zhang Helen Yan +2 位作者 Yuhao Geng Ke Wang Jianhong Xu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第10期2121-2126,共6页
In this article, a theoretical model for predicting the equilibrium morphology of gas–liquid Janus droplets was built. Based on this model, the effects of bubble radius and volume ratio on morphology change was syste... In this article, a theoretical model for predicting the equilibrium morphology of gas–liquid Janus droplets was built. Based on this model, the effects of bubble radius and volume ratio on morphology change was systematically studied. The increase of bubble radius causes the two parts(bubble and oil drop) in Janus droplets tend to merge while the impact of volume ratio is complicated. When volume ratio increases, these two parts firstly tend to merge, then gradually separate. The accuracy of this model was verified by experimental results. 展开更多
关键词 MICROFLUIDICS Gas–liquid–liquid emulsion Janus droplets
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Seasonal variation in abundance, diel vertical migration and body size of pelagic tunicate Salpa fusiformis in the Southern Yellow Sea 被引量:4
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作者 LIU Yongqin SUN Song ZHANG Guangtao 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第1期92-104,共13页
Mass occurrence of Salpafusiformis June 2007. In order to investigate its population was observed in the Southern Yellow Sea in May and recruitment and environmental adaptation, temporal variation of abundance, diel v... Mass occurrence of Salpafusiformis June 2007. In order to investigate its population was observed in the Southern Yellow Sea in May and recruitment and environmental adaptation, temporal variation of abundance, diel vertical migration (DVM) and length frequency distribution of both aggregate and solitary forms were studied with samples collected from eight months during September 2006 to August 2007. S. fusiformis presented in six months other than September and October 2006, and average abundance of aggregate and solitary forms peaked in June and May, respectively. In December, aggregate forms were absent in the bottom layer and performed irregular DVM from surface to 50 m depth, while solitary forms was too scarce to perform diel vertical distribution analysis. Both aggregate and solitary forms presented reverse DVM in May and June. They migrated upwards during daytime and concentrated in surface layer at sunset. The bimodal distribution of aggregate forms was found in April and the average size was largest in this month. In other months, the smaller aggregate forms (1-5 ram) dominated in populations except for May, when the modal size ranged from 2 to 8 mm. The average size of solitary forms was largest in December, followed by April. The skewed nomal distribution of solitary forms was found in May and June, with the modal size of 2-7 mm and 5-13 ram, respectively. 展开更多
关键词 Salpafusiformis SWARM diel vertical migration length frequency Southern Yellow Sea
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Opti mal design of alow-loss2-bit electrooptic analog-to-digital converter
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作者 ZHANG Chang-ming LIAO Yi-tao LIU Yong-zhi DAI Ji-zhi 《Optoelectronics Letters》 EI 2005年第3期185-187,共3页
The structure of the optical waveguide of 2-bit electrooptic A/D converter with proton-exchange micro prisms is optimized by the finite-difference beam propagation method (FD-BPM). The electrode parameters of the conv... The structure of the optical waveguide of 2-bit electrooptic A/D converter with proton-exchange micro prisms is optimized by the finite-difference beam propagation method (FD-BPM). The electrode parameters of the converter are optimized by conformal mapping. The optimal parameters are a half-wave voltage of (Vπ= 4.5 V) and a bandwidth of (Δf=1.4 GHz).A normalized transmitted power of 69.75% is obtained by FD-BMP and the output waveguide gap is 300 μm. 展开更多
关键词 优化设计 数字变换器 光学波导 电磁传播
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Dealing with Climate Change in a Digital Age
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作者 Rose A. Dyson 《Journal of Philosophy Study》 2017年第8期437-444,共8页
Digital technologies offer unprecedented opportunities in addressing climate change as public policy requirements increasingly pervade national boundaries. Health issues now merge with those in education, the environm... Digital technologies offer unprecedented opportunities in addressing climate change as public policy requirements increasingly pervade national boundaries. Health issues now merge with those in education, the environment, energy, culture, gender, security, and the economy. They offer enormous potential in mobilizing for political action. But they also have a dark side. Outgoing U.S. President Barack Obama issued a warning that social media in particular poses an existential threat to democracy. Their pervasive influence during the 2016 American presidential election highlighted the potential for the spread of fake news and alternative facts. These realities must be recognized and addressed if meaningful policies on climate change and future sustainability are to be achieved. The challenges ahead require a re-examination of overarching trends in mass media that date back to the middle of the last century. Warnings from scientists, scholars, and community activists indicate that, on the issue of climate change, time is running out. In his Encyclical on Climate Change and Inequality, Pope Francis amplified the urgent call to action. But collectively, we need to rethink the profit driven ways in which our proliferating digital technologies mitigate potential steps toward a sustainable future. In a myriad of forms that go well beyond the seductive and addicting trends of endless hours spent online, new and proliferating digital toys and gadgets are neither carbon neutral, nor as some proponents would have us believe, do they hold the sole promise of innovation and job creation. Additionally, their potential must be harnessed to maintain rather than disrupt social stability. 展开更多
关键词 digital health CLIMATE culture ECONOMY policy media sustainability DEMOCRACY WARNINGS DISRUPTION seduction
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Modal Wave Number Spectrum for Mesoscale Eddies
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作者 KANG Ying, PENG LinhuiDepartment of Physics, Ocean University of China, Qingdao 266071, P.R.China 《Journal of Ocean University of Qingdao》 2003年第2期218-223,共6页
The variations of ocean environmental parameters invariably result in variations of local modal wave numbers of a sound pressure field. The asymptotic Hankel transform with a short sliding window is applied to the com... The variations of ocean environmental parameters invariably result in variations of local modal wave numbers of a sound pressure field. The asymptotic Hankel transform with a short sliding window is applied to the complex sound pressure field in the water containing a mesoscale eddy to examine the variation of local modal wave numbers in such a range-dependent environment. The numerical simulation results show that modal wave number spectra obtained by this method can reflect the location and strength of a mesoscale eddy, therefore it can be used to monitor the strength and spatial scale of ocean mesoscale eddies. 展开更多
关键词 nomal mode wave number spectrum mesoscale eddies
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Impact of Sensor Technology for Line Protection Performance
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作者 Jianping Wang Murari Saha Torbjom Enairsson 《Journal of Energy and Power Engineering》 2014年第4期716-723,共8页
The paper has presented the impact on the line protection performance with the introduction of MUs (merging units) in the process bus level. The paper begins with the introduction on modem digital substation structu... The paper has presented the impact on the line protection performance with the introduction of MUs (merging units) in the process bus level. The paper begins with the introduction on modem digital substation structure and process bus. Then, the paper describes the performances of different sensors such as CTs (current transformers), CVTs (capacitive voltage transformers), FOCS (fiber optical current transducers) and FOVS (fiber optical voltage transducers). With the use of above transducers together with MUs, the performance of distance protection function and line differential protection function have been investigated and presented. Finally, conclusions based on the study are presented in the paper. 展开更多
关键词 Distance protection line differential protection current transformer voltage transformer digital substation non-conventional transformer.
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Analysis of Morphological Processes in a Disturbed Gravel-Bed River (Piave River): Integration of LiDAR Data and Colour Bathymetry
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作者 Fabio Delai Johnny Moretto Lorenzo Picco Emanuel Rigon Diego Ravazzolo Mario Aristide Lenzi 《Journal of Civil Engineering and Architecture》 2014年第5期639-648,共10页
The magnitude of river morphological changes are better analyzed through the use of quantitative approaches, wherein resolution accuracy and uncertainty assessment are treated as crucial key-factors. In this sense, th... The magnitude of river morphological changes are better analyzed through the use of quantitative approaches, wherein resolution accuracy and uncertainty assessment are treated as crucial key-factors. In this sense, the creation of precise DEMs (Digital Elevation Models) of rivers represents an affordable tool to analyze geomorphic variations and budgets, except for wetted areas, where reliable channel digitalization can normally be obtained only using expensive bathymetric surveys. The proposed work aims at improving channel surface models without having available bathymetric sensors, by deriving dry areas elevations from LiDAR data and water depth of wetted areas from aerial photos through a predictive depth-colour relationship. The methodology was applied to two different sub-reaches of the Piave River, a gravel-bed river which suffered severe flood events in 2010. Erosion and deposition patterns were identified through DEM differencing, showing a predominance of scour processes which can lead to channel instability situations. The bathymetric output was compared to other previously-derived models confirming the accuracy of the in-channel elevation estimates. Finally, a discussion on the role played by longitudinal protections during the studied flood events is proposed, focusing the attention on the incidence of two major bank erosions that removed significant volumes of stable areas. 展开更多
关键词 Colour bathymetry LiDAR data flood impacts fluvial erosion-deposition processes effect of river protections.
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Research on damage evolution of metal plate based on improved micropolar peridynamic model 被引量:1
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作者 Yang Huichao Xu Feiyun +1 位作者 Zhu Dasheng Liu Yadong 《Journal of Southeast University(English Edition)》 EI CAS 2019年第3期292-301,共10页
To study the damage evolution of the metal plate in elastic and plastic deformation stages, an improved micropolar peridynamic model is proposed to simulate the deformation process and damage evolution of metal materi... To study the damage evolution of the metal plate in elastic and plastic deformation stages, an improved micropolar peridynamic model is proposed to simulate the deformation process and damage evolution of metal materials with variable Poisson’s ratios in the elastic-plastic stages. Firstly, both the stretching and bending moments of the bonds between the material points are added to peridynamic pairwise force functions, and the coordinate transformation of the micro-beam made up of bonds is deduced. Therefore, the numerical calculation implementation of the improved micropolar peridynamic model is obtained. Then, the strain values are obtained by solving the difference equation based on the displacement values of material points, and the stress values can be calculated according to generalized Hook’s law. The elastic and plastic deformation stages can be estimated based on the von Mises yield criterion, and different constitutive equations are adopted to simulate the damage evolution. Finally, the proposed micropolar peridynamic model is applied to simulate the damage evolution of a metal plate with a hole under velocity boundary conditions, and the effectiveness of the model is verified through experiments. In the experiments, the displacement and strain distributions in the stretching process are analyzed by the digital image correlation(DIC) method. By comparing the results, the proposed model is more accurate than the bond-based peridynamic model and the error of the proposed model is 7.2% lower than that of the bond-based peridynamic model. By loading different velocity boundary conditions, the relationship between the loads and damage evolution is studied. 展开更多
关键词 micropolar peridynamic model elastic-plastic constitutive equation damage evolution plastic deformation digital image correlation tensile test
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