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Imaging plate scanners calibration and the attenuation behavior of imaging plate signals
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作者 薄楠 王乃彦 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期38-44,共7页
Based on previously reported work, we propose a new method for calibrating image plate(IP) scanners, offering greater flexibility and convenience, which can be extended to the calibration tasks of various scanner mode... Based on previously reported work, we propose a new method for calibrating image plate(IP) scanners, offering greater flexibility and convenience, which can be extended to the calibration tasks of various scanner models. This method was applied to calibrate the sensitivity of a GE Typhoon FLA 7000 scanner. Additionally, we performed a calibration of the spontaneous signal attenuation behavior for BAS-MS, BAS-SR, and BAS-TR type IPs under the 20±1℃ environmental conditions, and observed significant signal carrier diffusion behavior in BAS-MS IP. The calibration results lay a foundation for further research on the interaction between ultra-short, ultra-intense lasers and matter. 展开更多
关键词 image plate scanner ultra-short ultra-intense lasers
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In Situ Atomic Reconstruction Engineering Modulating Graphene-Like MXene-Based Multifunctional Electromagnetic Devices Covering Multi-Spectrum
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作者 Ting‑Ting Liu Qi Zheng +4 位作者 Wen‑Qiang Cao Yu‑Ze Wang Min Zhang Quan‑Liang Zhao Mao‑Sheng Cao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期247-261,共15页
With the diversified development of big data,detection and precision guidance technologies,electromagnetic(EM)functional materials and devices serving multiple spectrums have become a hot topic.Exploring the multispec... With the diversified development of big data,detection and precision guidance technologies,electromagnetic(EM)functional materials and devices serving multiple spectrums have become a hot topic.Exploring the multispectral response of materials is a challenging and meaningful scientific question.In this study,MXene/TiO_(2)hybrids with tunable conduction loss and polarization relaxation are fabricated by in situ atomic reconstruction engineering.More importantly,MXene/TiO_(2)hybrids exhibit adjustable spectral responses in the GHz,infrared and visible spectrums,and several EM devices are constructed based on this.An antenna array provides excellent EM energy harvesting in multiple microwave bands,with|S11|up to−63.2 dB,and can be tuned by the degree of bending.An ultra-wideband bandpass filter realizes a passband of about 5.4 GHz and effectively suppresses the transmission of EM signals in the stopband.An infrared stealth device has an emissivity of less than 0.2 in the infrared spectrum at wavelengths of 6-14μm.This work can provide new inspiration for the design and development of multifunctional,multi-spectrum EM devices. 展开更多
关键词 Graphene-like MXene hybrids multi-spectral response Multi-function antenna Ultra-wideband bandpass filter Electromagnetic device
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Extraction of Soil Organic Matter Information by Multi-spectral Remote Sensing Based on Diverse Landforms 被引量:1
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作者 杨建锋 马军成 +1 位作者 王令超 樊鹏 《Agricultural Science & Technology》 CAS 2016年第7期1744-1748,共5页
Based on diverse landforms, the correlation between soil organic matter content and multi-spectral band of remote sensing image was analyzed in this pa- per. In addition, the inversion models were built for the soil o... Based on diverse landforms, the correlation between soil organic matter content and multi-spectral band of remote sensing image was analyzed in this pa- per. In addition, the inversion models were built for the soil organic matter content in different landforms. The results showed that the spectral reflectance was nega- tively related to soil organic matter content; linear regression analysis of remove was performed throughout the bands using SPSS. When the inversion models were built based on all the bands, better fitting effect was obtained. The precision of in- version models built based on different landforms was higher than those built re- gardless landforms. Compared with the actual value, the identification level of soil organic matter content was 91 65% under the allowable error was 7%. It indicated that the extraction of soil organic matter with inversion model that was built based on different landforrrs was feasible with higher precision. 展开更多
关键词 Landform type multi-spectral Regression analysis Soil organic matter
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Low-dimensional multi-spectral space for color reproduction based on nonnegative constrained principal component analysis 被引量:1
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作者 王莹 曾平 +1 位作者 罗雪梅 谢琨 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期486-490,共5页
In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonne... In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonnegative constrained principal component analysis method is proposed to construct a low-dimensional multi-spectral space and accomplish the conversion between the new constructed space and the multispectral space. First, the reason behind the negative data is analyzed and a nonnegative constraint is imposed on the classic PCA. Then a set of nonnegative linear independence weight vectors of principal components is obtained, by which a lowdimensional space is constructed. Finally, a nonlinear optimization technique is used to determine the projection vectors of the high-dimensional multi-spectral data in the constructed space. Experimental results show that the proposed method can keep the reconstructed spectral data in [ 0, 1 ]. The precision of the space created by the proposed method is equivalent to or even higher than that by the PCA. 展开更多
关键词 spectral color science nonnegative constrained principal component analysis low-dimensional spectral space nonlinear optimization multi-spectral images spectral reflectance
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Extracting Feature Bands for Damaged Rice Leaves by Planthoppers Using Multi-spectral Imaging Technology
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作者 曹鹏飞 李宏宁 +2 位作者 杨卫平 林立波 冯洁 《Agricultural Science & Technology》 CAS 2013年第11期1642-1645,1669,共5页
[Objective] The aim of this study was to extract effective feature bands of damaged rice leaves by planthoppers to make identification and classification rapidly from great amounts of imaging spectral data. [Method] T... [Objective] The aim of this study was to extract effective feature bands of damaged rice leaves by planthoppers to make identification and classification rapidly from great amounts of imaging spectral data. [Method] The experiment, using multi-spectral imaging system, acquired the multi-spectral images of damaged rice leaves from band 400 to 720 nm by interval of 5 nm. [Result] According to the principle of band index, it was calculated that the bands at 515, 510, 710, 555, 630, 535, 505, 530 and 595 nm were having high band index value with rich information and little correlation. Furthermore, the experiment used two classification methods and calcu-lated the classification accuracy higher than 90.00% for feature bands and ful bands of damaged rice leaves by planthoppers respectively. [Conclusion] It can be con-cluded that these bands can be considered as effective feature bands to identify damaged rice leaves by planthoppers quickly from a large scale of crops. 展开更多
关键词 Feature bands multi-spectral imaging Damaged rice leaves Planthop-pers Classification accuracy
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Robust key point descriptor for multi-spectral image matching 被引量:3
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作者 Yueming Qin Zhiguo Cao +1 位作者 Wen Zhuo Zhenghong Yu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期681-687,共7页
Histogram of collinear gradient-enhanced coding (HCGEC), a robust key point descriptor for multi-spectral image matching, is proposed. The HCGEC mainly encodes rough structures within an image and suppresses detaile... Histogram of collinear gradient-enhanced coding (HCGEC), a robust key point descriptor for multi-spectral image matching, is proposed. The HCGEC mainly encodes rough structures within an image and suppresses detailed textural information, which is desirable in multi-spectral image matching. Experiments on two multi-spectral data sets demonstrate that the proposed descriptor can yield significantly better results than some state-of- the-art descriptors. 展开更多
关键词 collinear gradient-enhanced coding (CGEC) key pointdescriptor multi-spectral image matching.
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MULTI-SPECTRAL AND HYPERSPECTRAL IMAGE FUSION USING 3-D WAVELET TRANSFORM 被引量:5
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作者 Zhang Yifan He Mingyi 《Journal of Electronics(China)》 2007年第2期218-224,共7页
Image fusion is performed between one band of multi-spectral image and two bands of hyperspectral image to produce fused image with the same spatial resolution as source multi-spectral image and the same spectral reso... Image fusion is performed between one band of multi-spectral image and two bands of hyperspectral image to produce fused image with the same spatial resolution as source multi-spectral image and the same spectral resolution as source hyperspeetral image. According to the characteristics and 3-Dimensional (3-D) feature analysis of multi-spectral and hyperspectral image data volume, the new fusion approach using 3-D wavelet based method is proposed. This approach is composed of four major procedures: Spatial and spectral resampling, 3-D wavelet transform, wavelet coefficient integration and 3-D inverse wavelet transform. Especially, a novel method, Ratio Image Based Spectral Resampling (RIBSR)method, is proposed to accomplish data resampling in spectral domain by utilizing the property of ratio image. And a new fusion rule, Average and Substitution (A&S) rule, is employed as the fusion rule to accomplish wavelet coefficient integration. Experimental results illustrate that the fusion approach using 3-D wavelet transform can utilize both spatial and spectral characteristics of source images more adequately and produce fused image with higher quality and fewer artifacts than fusion approach using 2-D wavelet transform. It is also revealed that RIBSR method is capable of interpolating the missing data more effectively and correctly, and A&S rule can integrate coefficients of source images in 3-D wavelet domain to preserve both spatial and spectral features of source images more properly. 展开更多
关键词 Image fusion 3-Dimensional (3-D) wavelet transform multi-spectral HYPERSPECTRAL
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Chlorophyll Content Retrieval of Rice Canopy with Multi-spectral Inversion Based on LS-SVR Algorithm 被引量:2
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作者 Jin Si-yu Su Zhong-bin +3 位作者 Xu Zhe-nan Jia Yin-jiang Yan Yu-guang Jiang Tao 《Journal of Northeast Agricultural University(English Edition)》 CAS 2019年第1期53-63,共11页
To monitor growth and predict the yield of rice over a large area, the chlorophyll contents in the rice canopy were estimated using the unmanned aerial vehicle(UAV) remote sensing technology. In this work, multi-spect... To monitor growth and predict the yield of rice over a large area, the chlorophyll contents in the rice canopy were estimated using the unmanned aerial vehicle(UAV) remote sensing technology. In this work, multi-spectral image information of the rice crop was obtained using a 6-channel multi-spectral camera mounted on a fixed wing UAV, which was flown 600 m above the ground, between 11: 00-14: 00 on a sunny day in summer. The measured chlorophyll values were collected as sample sets. The s-REP index was screened out to estimate chlorophyll contents through the analysis of six kinds of spectral indexes of chlorophyll estimated capacity. An inversion model of the chlorophyll contents was then built using the least square support vector regression(LS-SVR)algorithm, with calibration and prediction R-square values of 0.89 and 0.83, respectively. Finally, remote sensing mapping for a UAV image of the Fangzheng County Dexter Rice Planting Park was accomplished using the inversion model. The inversion and measured values were then compared using regression fitting. R-square and root-mean-square error of the fitting model were 0.79 and 2.39,respectively. The results demonstrated that accurate estimation of rice-canopy chlorophyll contents was feasible using the LS-SVR inversion model developed using the s-REP vegetation index. 展开更多
关键词 remote sensing CHLOROPHYLL rice UAV multi-spectral INVERSION LS-SVR
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Multi-Spectral and Fluorescence Imaging in Prevention of Overdose of Herbicides: The Case of Maize 被引量:1
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作者 Anicet K. Kouakou Adama P. Soro +1 位作者 Alvarez K. Taky Jérémie T. Zoueu 《Spectral Analysis Review》 2017年第2期11-24,共14页
Evaluation of the impact of herbicides on maize was done through multi- spectral and multi-modal imaging and multi-spectral fluorescence imaging combined with statistical methods. Spectra containing 13 wavelengths ran... Evaluation of the impact of herbicides on maize was done through multi- spectral and multi-modal imaging and multi-spectral fluorescence imaging combined with statistical methods. Spectra containing 13 wavelengths ranging from 375 nm to 940 nm were derived from multi-spectral images in transmission, reflection and scattering mode and fluorescence images obtained using high-pass filters (F450 nm, F500 nm, F550 nm, F600 nm, F650 nm) on control maize samples and maize samples treated with Herbextra herbicide were used. The appearance of the spectra allowed us to characterize the effect of the herbicide on the maize pigment concentration. The fluorescence images allowed us to track the fate of absorbed energy and through PLS-DA and SVM-DA to discriminate the two leaf categories with very low error rates for the test, i.e. 4.9% and 2% respectively. The results of this technique can be used in the context of precision agriculture. 展开更多
关键词 MAIZE Herbextra multi-spectral IMAGING Multimodal IMAGING FLUORESCENCE PLS-DA SVM-DA
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New Abnormal Cervical Cell Detection Method of Multi-Spectral Pap Smears
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作者 CAO Feng CHEN Shuzhen ZENG Libo 《Wuhan University Journal of Natural Sciences》 CAS 2007年第3期476-480,共5页
Considering the problem of traditional cervical cancer detection method that brings high false negative rate (FNR) and high false positive rate (FPR), a new abnormal cervical cells detection method of multi-spectr... Considering the problem of traditional cervical cancer detection method that brings high false negative rate (FNR) and high false positive rate (FPR), a new abnormal cervical cells detection method of multi-spectral Pap smear is proposed in this thesis, on the basis of multi-spectral microscopic imaging technology and computer automotive recognition technology. At first, image in a specific wave band is segmented according to the relationship between intensity and spectrum of each pixel. Then, multi-spectral features of each pixel are extracted making use of improved cosine correlation analysis (CCA) algorithm. Combined with the characteristic of each cell's area, final definition is made. Experiments have proved the new approach could identify abnormal cells efficiently as well as lower FNR and FPR. 展开更多
关键词 multi-spectral cervical pap smears improved CCA
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Solar Multi-Spectral Radiometric Observations of Atmospheric Optical Thickness over Passarlapudi Gas Well Blow-Out Site in India
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《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1997年第3期130-137,共8页
SolarMulti-SpectralRadiometricObservationsofAtmosphericOpticalThicknesoverPasarlapudiGasWelBlow-OutSiteinInd... SolarMulti-SpectralRadiometricObservationsofAtmosphericOpticalThicknesoverPasarlapudiGasWelBlow-OutSiteinIndiaG.Pandithuraian... 展开更多
关键词 BLOW OVER SITE Solar multi-spectral Radiometric Observations of Atmospheric Optical Thickness over Passarlapudi Gas Well Blow-Out Site in India
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特征自适应的复杂曲面扫描路径生成方法
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作者 林雪竹 王庭轩 +1 位作者 郭丽丽 李丽娟 《红外与激光工程》 EI CSCD 北大核心 2024年第5期117-132,共16页
为了解决现有自动化扫描方法在面对复杂曲面时扫描完整性不足、普适性不佳等问题,提出了一种特征自适应的自动化扫描路径规划方法。首先,构建了激光扫描仪的扫描约束条件,分析其对扫描精度的影响,为特征自适应的复杂扫描路径规划提供理... 为了解决现有自动化扫描方法在面对复杂曲面时扫描完整性不足、普适性不佳等问题,提出了一种特征自适应的自动化扫描路径规划方法。首先,构建了激光扫描仪的扫描约束条件,分析其对扫描精度的影响,为特征自适应的复杂扫描路径规划提供理论支撑。其次,针对扫描仪姿态规划问题,提出了一种新的测量倾角约束聚类算法,对离散复杂曲面后获得的采样点进行聚类处理,实现扫描仪姿态的规划,并在此基础上获得扫描路径点。再次,针对扫描路径规划问题,引入法向矢量夹角矩阵作为惩罚矩阵,优化改进最近邻算法,实现符合需求的扫描路径规划。最后,为验证该方法可行有效,以汽车车门作为扫描对象,搭建了一个组合式自动化柔性测量系统,与传统行切扫描方法、手动扫描方法进行对比试验。试验结果表明,该方法相较于行切扫描方法在扫描仪姿态变换次数上减少了54%,测量精度提高了64.5%,降低了人工干预因素的影响,扫描完整性与手动扫描方法接近,可以实现针对复杂曲面的自动化扫描测量。 展开更多
关键词 激光扫描仪 扫描路径规划 扫描约束 特征自适应 聚类处理
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基于ABVS影像组学列线图术前预测T1期乳腺癌腋窝淋巴结转移
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作者 张宇 汪珺莉 +1 位作者 范莉芳 陈国仙 《现代肿瘤医学》 CAS 2024年第16期3085-3092,共8页
目的:探讨基于自动乳腺全容积成像(automatic breast volume scanner,ABVS)影像组学构建的列线图模型术前预测T1期乳腺癌腋窝淋巴结(axillary lymph node,ALN)转移的价值。方法:收集华东师范大学附属芜湖医院158例T1期乳腺癌患者的临床... 目的:探讨基于自动乳腺全容积成像(automatic breast volume scanner,ABVS)影像组学构建的列线图模型术前预测T1期乳腺癌腋窝淋巴结(axillary lymph node,ALN)转移的价值。方法:收集华东师范大学附属芜湖医院158例T1期乳腺癌患者的临床病理及影像资料,按7比3将患者随机分为训练组(n=110)及验证组(n=48)。利用MaZda纹理分析软件基于ABVS最大冠状面图像提取影像组学特征,并采用最小绝对收缩和选择算子算法(least absolute shrinkage and selection operator,LASSO)回归降维筛选最优特征,并构建影像组学标签评分(radiomics score,radscore)。通过单因素与多因素Logistic回归分析筛选预测T1期乳腺癌ALN转移的独立危险因子,构建联合预测模型,并绘制列线图。用受试者工作特征(receiver operating characteristic,ROC)曲线及曲线下面积(area under curve,AUC)进行模型性能评价,Hosmer-Lemeshow检验进行拟合优度评价。校准曲线评价模型的校准度,Delong检验比较模型的诊断效能,决策曲线分析(decision curve analysis,DCA)评估模型的临床实用性。结果:单因素与多因素Logistic回归发现象限、冠状面汇聚征、超声淋巴结阳性为独立危险因素。联合模型训练组、验证组AUC分别为0.944、0.862,Delong检验联合模型诊断效能最高,Hosmer-Lemeshow检验模型均拟合较好(训练组χ^(2)=6.877,P=0.550;验证组χ^(2)=13.904,P=0.084),校准曲线及DCA表明列线图具有较高的校准度及较好的临床适用性。结论:基于ABVS影像组学列线图术前能有效的预测T1期乳腺癌ALN转移风险,构建的列线图能够可视化预测结果,为精准诊疗提供无创手段。 展开更多
关键词 乳腺癌 腋窝淋巴结 影像组学 ABVS
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岩性元素扫描测井在准确识别岩性中应用
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作者 申本科 胡渤 +2 位作者 李浩 齐真真 王振华 《内蒙古石油化工》 CAS 2024年第1期16-20,共5页
对于非常规储层和复杂岩性储层,利用常规测井曲线准确识别岩性、求取地层参数比较困难,元素扫描(Litho Scanner)测井通过对地层中元素的直接测量,能够提供地层中元素含量,对于特定的岩石(碎屑岩、碳酸盐等),可以通过元素含量计算地层中... 对于非常规储层和复杂岩性储层,利用常规测井曲线准确识别岩性、求取地层参数比较困难,元素扫描(Litho Scanner)测井通过对地层中元素的直接测量,能够提供地层中元素含量,对于特定的岩石(碎屑岩、碳酸盐等),可以通过元素含量计算地层中不同矿物组分的含量,进而进行对岩性的准确识别,识别出地层中绿泥石、蒙脫石、伊利石、钠长石、石英、方解石、白云石和黄铁矿等地层矿物及其含量,完成地层岩石矿物的评价。 展开更多
关键词 元素扫描测井 地层 元素 矿物 组分含量
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现代测绘技术在古建烫样数字化项目中的应用
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作者 王莫 《文物保护与考古科学》 北大核心 2024年第2期171-176,共6页
烫样是研究清代皇家建筑的珍贵文物,为配合文物信息数字化工作的开展,针对烫样数据的采集和处理方法进行了深入研究。在综合考虑多种数据采集方法的特点及烫样数字化记录的难点后,选择使用手持式三维扫描仪与多视角三维重建技术相结合... 烫样是研究清代皇家建筑的珍贵文物,为配合文物信息数字化工作的开展,针对烫样数据的采集和处理方法进行了深入研究。在综合考虑多种数据采集方法的特点及烫样数字化记录的难点后,选择使用手持式三维扫描仪与多视角三维重建技术相结合的方式来进行烫样的基础数据采集,并通过实践总结出了一套完整的数据采集和处理工作流程。与此同时,针对成果可能的应用方式做了些许尝试,且为数据的后期维护与进一步利用拟定了数据管理系统的建设方案。 展开更多
关键词 烫样 手持三维扫描 多视角三维重建 彩色纹理模型 正射影像图 数据管理系统
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自发性全段食管黏膜下血肿2例并文献复习
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作者 张发平 束玲玲 鲁大林 《中国医药科学》 2024年第6期190-193,共4页
食管黏膜下血肿(ESH)是临床少见的疾病,首发症状多为胸痛,与其他胸痛疾病易混淆。本文回顾性分析安徽省皖南康复医院收治的2例自发性全段ESH患者的临床资料、胃镜及胸部CT资料。2例患者均为老年女性,均在无明显诱因下突发胸痛、吞咽困难... 食管黏膜下血肿(ESH)是临床少见的疾病,首发症状多为胸痛,与其他胸痛疾病易混淆。本文回顾性分析安徽省皖南康复医院收治的2例自发性全段ESH患者的临床资料、胃镜及胸部CT资料。2例患者均为老年女性,均在无明显诱因下突发胸痛、吞咽困难,经过胃镜及胸部CT确诊。入院行禁食、抑酸、护胃、解痉、抗炎及补液等保守治疗,1例患者在入院第3天出现呕血,另1例患者在入院第2天便血,同时患者症状明显改善,分别于第11天和第15天顺利出院,1个月后复查ESH消失,均无复发。2例ESH保守治疗均取得良好的临床疗效,尤其在血肿减压(呕血和便血)的情况下,有助于患者的症状改善。本文对ESH发病机制、临床表现、诊断、治疗和转归进行文献复习,以期提高临床医生对本病的诊治水平。 展开更多
关键词 食管黏膜下血肿 胃镜 体层摄影术 X线计算机 胸痛
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3种口内扫描仪用于咬合关系记录的准确度研究 被引量:1
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作者 王思谕 周哲青 +2 位作者 袁泉 岳莉 杨胜涛 《华西口腔医学杂志》 CAS CSCD 北大核心 2024年第2期227-233,共7页
目的探究3种口内扫描仪用于获取最大牙尖交错位(MIP)咬合关系的准确度,为临床实践提供参考。方法招募10名上下颌牙列完整、咬合关系正常的受试者。对照组采用面弓转移和咬合记录将位于MIP的上下颌石膏模型固定在架上,并使用桌面扫描仪... 目的探究3种口内扫描仪用于获取最大牙尖交错位(MIP)咬合关系的准确度,为临床实践提供参考。方法招募10名上下颌牙列完整、咬合关系正常的受试者。对照组采用面弓转移和咬合记录将位于MIP的上下颌石膏模型固定在架上,并使用桌面扫描仪对固定的模型进行扫描以获得数字化模型数据;实验组分别使用Trios 3、Carestream 3600以及Aoralscan 3口内扫描仪对受试者进行口内扫描以获取位于MIP时上下颌口扫模型数据。在对照组数字化模型的上下颌双侧中切牙、尖牙和第一磨牙上设置测量点并测量上下颌对应同名牙上测量点之间的距离,获得测量的距离之和D_(A),同时计算模型中切牙区、尖牙区以及第一磨牙区的测量点间距离之和,分别记为D_(I)、D_(C)、D_(M)。将添加测量点的对照组上下颌模型分别与实验组上下颌口扫模型进行精确匹配,计算匹配后对照组模型的D_(A)、D_(I)、D_(C)和D_(M)。对对照组和实验组获得的D_(A)、D_(I)、D_(C)、D_(M)进行统计学分析,以评估3种口内扫描仪记录咬合关系的准确度。结果对照组D_(A)、D_(I)、D_(C)、D_(M)的值分别为(39.58±6.40)、(13.64±3.58)、(14.91±2.85)、(11.03±1.56)mm,Trios 3组相应的值为(38.99±6.60)、(13.42±3.66)、(14.55±2.87)、(11.03±1.69)mm,Carestream 3600组相应的值为(38.57±6.36)、(13.56±3.68)、(14.45±2.85)、(10.55±1.41)mm,Aoralscan 3组相应的值为(38.16±5.69)、(13.03±3.54)、(14.23±2.59)、(10.90±1.54)mm。方差分析显示无论是整体偏差D_(A)(P=0.96),还是局部偏差D_(I)(P=0.98)、D_(C)(P=0.96)、D_(M)(P=0.89),3种口内扫描仪获取的数字化模型与对照组模型之间差异均无统计学意义。结论在规范的操作流程下,3种口内扫描仪获取的MIP咬合关系与传统方法无差异,满足临床诊疗的需求。 展开更多
关键词 口内扫描仪 最大牙尖交错位 咬合关系 数字化牙科
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基于PhotoModeler Scanner的普通数码相机快速检校研究 被引量:16
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作者 程效军 许诚权 周行泉 《遥感信息》 CSCD 2011年第4期80-84,89,共6页
随着分辨率的不断提高与价格的日益降低,数码相机已成为近景摄影测量的基本设备,而相机的准确检校是保证量测精度的关键因素。借助于PhotoModeler Scanner软件,本文实现了相机的快速准确检校,并对野外检校的稳定性和质量进行了分析,说... 随着分辨率的不断提高与价格的日益降低,数码相机已成为近景摄影测量的基本设备,而相机的准确检校是保证量测精度的关键因素。借助于PhotoModeler Scanner软件,本文实现了相机的快速准确检校,并对野外检校的稳定性和质量进行了分析,说明该检校方法简便可靠。 展开更多
关键词 数码相机 PhotoModeler scanner 野外检校 精度分析
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固井质量评价仪Isolation Scanner在塔里木油田套管检测方面的应用 被引量:5
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作者 范文同 郑新华 +3 位作者 刘永林 郭秀丽 袁仕俊 李进福 《石油天然气学报》 CAS CSCD 2014年第2期87-91,7,共5页
塔里木油田地质构造复杂,油气埋藏普遍偏深,深井、超深井钻井工艺复杂,套管柱结构多样,如何检测钻井和后续开发造成的套管磨损和腐蚀情况,成为测井工程的一大难题。为了解决该难题,油田引进了最新一代的固井质量评价仪Isolation Scanner... 塔里木油田地质构造复杂,油气埋藏普遍偏深,深井、超深井钻井工艺复杂,套管柱结构多样,如何检测钻井和后续开发造成的套管磨损和腐蚀情况,成为测井工程的一大难题。为了解决该难题,油田引进了最新一代的固井质量评价仪Isolation Scanner,该仪器通过脉冲回波测量和挠曲波衰减测量,可对套管结构进行检测,同时对套管磨损、腐蚀及套管居中情况进行定量评价。详细介绍了Isolation Scanner仪器的工作原理,并介绍了该仪器在塔里木油田套管检测方面的应用情况,通过实例分析认为该仪器的应用效果良好。 展开更多
关键词 固井质量评价仪(Isolation scanner) 套管检测 套管磨损 套管腐蚀 套管居中度测量
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面向未来月面科考的熔岩管实景三维建模技术研究
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作者 阳乔 康志忠 +2 位作者 胡腾 叶晨鸣 刘东鸣 《深空探测学报(中英文)》 CSCD 北大核心 2024年第4期355-364,共10页
提出一种融合机载LiDAR,贴近摄影测量,以及GeoSLAM手持激光扫描仪点云数据来源的面向未来月面科考的熔岩管实景三维建模方法。首先进行实体划分,随后依据语义信息进行实体特征提取,并提出一种新的mesh模型构建方法,通过多层次模型构建... 提出一种融合机载LiDAR,贴近摄影测量,以及GeoSLAM手持激光扫描仪点云数据来源的面向未来月面科考的熔岩管实景三维建模方法。首先进行实体划分,随后依据语义信息进行实体特征提取,并提出一种新的mesh模型构建方法,通过多层次模型构建方法以及骨架加细节建模方法来对熔岩管内表面的模型进行mesh模型构建,最后在模型内部不同层间分别构建实体,以模拟不同层的原始状态,并以此对层厚、剥落物体积两方面进行测量。通过对位于黑龙江省镜泊湖的熔岩管三维建模表明:基于多源数据融合的熔岩管实景三维建模方法具有高精度、高真实度等特点,为后续月球熔岩管天窗检测、地月模拟对比以及内部探测提供重要参考。 展开更多
关键词 三维重建 机载LIDAR 贴近摄影测量 熔岩管 GeoSLAM扫描仪
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