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Pulmonary Edema and Pleural Effusion Detection Using Efficient Net-V1-B4 Architecture and AdamW Optimizer from Chest X-Rays Images
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作者 Anas AbuKaraki Tawfi Alrawashdeh +4 位作者 Sumaya Abusaleh Malek Zakarya Alksasbeh Bilal Alqudah Khalid Alemerien Hamzah Alshamaseen 《Computers, Materials & Continua》 SCIE EI 2024年第7期1055-1073,共19页
This paper presents a novelmulticlass systemdesigned to detect pleural effusion and pulmonary edema on chest Xray images,addressing the critical need for early detection in healthcare.A new comprehensive dataset was f... This paper presents a novelmulticlass systemdesigned to detect pleural effusion and pulmonary edema on chest Xray images,addressing the critical need for early detection in healthcare.A new comprehensive dataset was formed by combining 28,309 samples from the ChestX-ray14,PadChest,and CheXpert databases,with 10,287,6022,and 12,000 samples representing Pleural Effusion,Pulmonary Edema,and Normal cases,respectively.Consequently,the preprocessing step involves applying the Contrast Limited Adaptive Histogram Equalization(CLAHE)method to boost the local contrast of the X-ray samples,then resizing the images to 380×380 dimensions,followed by using the data augmentation technique.The classification task employs a deep learning model based on the EfficientNet-V1-B4 architecture and is trained using the AdamW optimizer.The proposed multiclass system achieved an accuracy(ACC)of 98.3%,recall of 98.3%,precision of 98.7%,and F1-score of 98.7%.Moreover,the robustness of the model was revealed by the Receiver Operating Characteristic(ROC)analysis,which demonstrated an Area Under the Curve(AUC)of 1.00 for edema and normal cases and 0.99 for effusion.The experimental results demonstrate the superiority of the proposedmulti-class system,which has the potential to assist clinicians in timely and accurate diagnosis,leading to improved patient outcomes.Notably,ablation-CAM visualization at the last convolutional layer portrayed further enhanced diagnostic capabilities with heat maps on X-ray images,which will aid clinicians in interpreting and localizing abnormalities more effectively. 展开更多
关键词 image classification decision support system EfficientNet-V1-B4 AdamW optimizer pulmonary edema pleural effusion chest X-rays
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Power of SAR Imagery and Machine Learning in Monitoring Ulva prolifera:A Case Study of Sentinel-1 and Random Forest
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作者 ZHENG Longxiao WU Mengquan +5 位作者 XUE Mingyue WU Hao LIANG Feng LI Xiangpeng HOU Shimin LIU Jiayan 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1134-1143,共10页
Automatically detecting Ulva prolifera(U.prolifera)in rainy and cloudy weather using remote sensing imagery has been a long-standing problem.Here,we address this challenge by combining high-resolution Synthetic Apertu... Automatically detecting Ulva prolifera(U.prolifera)in rainy and cloudy weather using remote sensing imagery has been a long-standing problem.Here,we address this challenge by combining high-resolution Synthetic Aperture Radar(SAR)imagery with the machine learning,and detect the U.prolifera of the South Yellow Sea of China(SYS)in 2021.The findings indicate that the Random Forest model can accurately and robustly detect U.prolifera,even in the presence of complex ocean backgrounds and speckle noise.Visual inspection confirmed that the method successfully identified the majority of pixels containing U.prolifera without misidentifying noise pixels or seawater pixels as U.prolifera.Additionally,the method demonstrated consistent performance across different im-ages,with an average Area Under Curve(AUC)of 0.930(+0.028).The analysis yielded an overall accuracy of over 96%,with an average Kappa coefficient of 0.941(+0.038).Compared to the traditional thresholding method,Random Forest model has a lower estimation error of 14.81%.Practical application indicates that this method can be used in the detection of unprecedented U.prolifera in 2021 to derive continuous spatiotemporal changes.This study provides a potential new method to detect U.prolifera and enhances our under-standing of macroalgal outbreaks in the marine environment. 展开更多
关键词 Ulva prolifera Random Forest Sentinel-1 Synthetic Aperture Radar(SAR)image machine learning remote sensing Google Earth Engine South Yellow Sea of China
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MRI T_2 star mapping、T_1 images与3D DESS融合图在隐匿性膝关节软骨损伤中的应用 被引量:4
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作者 范伟雄 杨志企 +3 位作者 程凤燕 黄健 于昭 侯文忠 《临床医学工程》 2017年第4期437-439,共3页
目的探讨T_2 star mapping、T_1 images与3D DESS融合伪彩图在关节软骨损伤中的诊断价值。方法对26例关节软骨损伤患者行T_2 star mapping、T_1 images和3D DESS扫描,并将T_1 images、T_2 star mapping与3D DESS图像融合,评价患者股骨... 目的探讨T_2 star mapping、T_1 images与3D DESS融合伪彩图在关节软骨损伤中的诊断价值。方法对26例关节软骨损伤患者行T_2 star mapping、T_1 images和3D DESS扫描,并将T_1 images、T_2 star mapping与3D DESS图像融合,评价患者股骨、胫骨、髌骨关节软骨损伤程度并与关节镜结果对比,计算融合伪彩图诊断软骨损伤的特异性、敏感性及与关节镜诊断结果一致性。结果 T_1 images-3D DESS融合伪彩图诊断关节软骨损伤的敏感度、特异度及Kappa值分别为92.8%、93.0%、0.769,T_2 star mapping-3D DESS融合伪彩图诊断关节软骨损伤的敏感度、特异度及Kappa值分别为91.4%、94.2%、0.787。结论 T_2 star mapping、T_1 images与3D DESS融合伪彩图在关节软骨早期损伤评价上优于关节镜。 展开更多
关键词 膝关节 关节软骨 磁共振成像 T2 star mapping T1 imageS 3D DESS
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Performances of conventional fusion methods evaluated for inland water body observation using GF-1 image 被引量:3
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作者 Yong Du Xiaoyu Zhang +1 位作者 Zhihua Mao Jianyu Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第1期172-179,共8页
Satellite remote sensing of inland water body requires a high spatial resolution and a multiband narrow spectral resolution, which makes the fusion between panchromatic(PAN) and multi-spectral(MS) images particularly ... Satellite remote sensing of inland water body requires a high spatial resolution and a multiband narrow spectral resolution, which makes the fusion between panchromatic(PAN) and multi-spectral(MS) images particularly important. Taking the Daquekou section of the Qiantang River as an observation target, four conventional fusion methods widely accepted in satellite image processing, including pan sharpening(PS), principal component analysis(PCA), Gram-Schmidt(GS), and wavelet fusion(WF), are utilized to fuse MS and PAN images of GF-1.The results of subjective and objective evaluation methods application indicate that GS performs the best,followed by the PCA, the WF and the PS in the order of descending. The existence of a large area of the water body is a dominant factor impacting the fusion performance. Meanwhile, the ability of retaining spatial and spectral informations is an important factor affecting the fusion performance of different fusion methods. The fundamental difference of reflectivity information acquisition between water and land is the reason for the failure of conventional fusion methods for land observation such as the PS to be used in the presence of the large water body. It is suggested that the adoption of the conventional fusion methods in the observing water body as the main target should be taken with caution. The performances of the fusion methods need re-assessment when the large-scale water body is present in the remote sensing image or when the research aims for the water body observation. 展开更多
关键词 GF-1 satellite image FUSION methods FUSION evaluation INLAND water body
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A lightweight symmetric image encryption cryptosystem in wavelet domain based on an improved sine map
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作者 陈柏池 黄林青 +2 位作者 蔡述庭 熊晓明 张慧 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期266-276,共11页
In the era of big data,the number of images transmitted over the public channel increases exponentially.As a result,it is crucial to devise the efficient and highly secure encryption method to safeguard the sensitive ... In the era of big data,the number of images transmitted over the public channel increases exponentially.As a result,it is crucial to devise the efficient and highly secure encryption method to safeguard the sensitive image.In this paper,an improved sine map(ISM)possessing a larger chaotic region,more complex chaotic behavior and greater unpredictability is proposed and extensively tested.Drawing upon the strengths of ISM,we introduce a lightweight symmetric image encryption cryptosystem in wavelet domain(WDLIC).The WDLIC employs selective encryption to strike a satisfactory balance between security and speed.Initially,only the low-frequency-low-frequency component is chosen to encrypt utilizing classic permutation and diffusion.Then leveraging the statistical properties in wavelet domain,Gaussianization operation which opens the minds of encrypting image information in wavelet domain is first proposed and employed to all sub-bands.Simulations and theoretical analysis demonstrate the high speed and the remarkable effectiveness of WDLIC. 展开更多
关键词 image encryption discrete wavelet transform 1D-chaotic system selective encryption Gaussianization operation
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The brightness reversal of submarine sand waves in “HJ-1A/B” CCD sun glitter images 被引量:2
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作者 HE Xiekai CHEN Ninghua +1 位作者 ZHANG Huaguo GUAN Weibing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第1期94-99,共6页
The brightness reversal of submarine sand waves appearing in the small satellite constellation for environ- ment and disaster monitoring and forecasting ("HJ- 1A/B") CCD sun glitter images can affect the observati... The brightness reversal of submarine sand waves appearing in the small satellite constellation for environ- ment and disaster monitoring and forecasting ("HJ- 1A/B") CCD sun glitter images can affect the observation and depth inversion of sand wave topography. The simulations of the normalized sun glitter radiance on the submarine sand waves confirm that the reversal would happen at a specific sensor viewing angle, defined as the critical angle. The difference between the calculated critical angle position and the reversal position in the image is about 1', which is excellent in agreement. Both the simulation and actual image show that sand wave crests would be indistinct at the reversal position, which may cause problems when using these sun glitter images to analyze spatial characteristics and migration of sand waves. When using the sun glitter image to obtain the depth inversion, one should take the advantage of image properties of sand waves and choose the location in between the reversal position and the brightest position. It is also necessary to pay attention to the brightness reversal when using "HI-1A/B" CCD images to analyze other oceanic features, such as internal waves, oil slicks, eddies, and ship wakes. 展开更多
关键词 "HJ-1A/B" CCD sun glitter image submarine sand waves brightness reversal Taiwan Banks
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Population Spatial Distribution Based on Luojia 1-01 Nighttime Light Image:A Case Study of Beijing 被引量:1
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作者 SUN Lu WANG Jia CHANG Shuping 《Chinese Geographical Science》 SCIE CSCD 2021年第6期966-978,共13页
With the continuous development of urbanization in China,the country’s growing population brings great challenges to urban development.By mastering the refined population spatial distribution in administrative units,... With the continuous development of urbanization in China,the country’s growing population brings great challenges to urban development.By mastering the refined population spatial distribution in administrative units,the quantity and agglomeration of population distribution can be estimated and visualized.It will provide a basis for a more rational urban planning.This paper takes Beijing as the research area and uses a new Luojia1-01 nighttime light image with high resolution,land use type data,Points of Interest(POI)data,and other data to construct the population spatial index system,establishing the index weight based on the principal component analysis.The comprehensive weight value of population distribution in the study area was then used to calculate the street population distribution of Beijing in 2018.Then the population spatial distribution was visualize using GIS technology.After accuracy assessments by comparing the result with the WorldPop data,the accuracy has reached 0.74.The proposed method was validated as a qualified method to generate population spatial maps.By contrast of local areas,Luojia 1-01 data is more suitable for population distribution estimation than the NPP/VIIRS(Net Primary Productivity/Visible infrared Imaging Radiometer)nighttime light data.More geospatial big data and mathematical models can be combined to create more accurate population maps in the future. 展开更多
关键词 Luojia1-01 nighttime light image principal component analysis points of interest landuse type data population spatial distribution
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HY-1C Coastal Zone Imager observations of the suspended sediment content distribution details in the sea area near Hong Kong-Zhuhai-Macao Bridge in China 被引量:1
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作者 Lina Cai Minrui Zhou +4 位作者 Xiaojun Yan Jianqiang Liu Qiyan Ji Yuxiang Chen Juncheng Zuo 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第11期126-138,共13页
The impacts of the Hong Kong-Zhuhai-Macao Bridge(HKZMB)on suspended sediment content(SSC)were analysed in the Zhujiang River Estuary based on data from HY-1C,which was launched in September 2018 in China,carrying Coas... The impacts of the Hong Kong-Zhuhai-Macao Bridge(HKZMB)on suspended sediment content(SSC)were analysed in the Zhujiang River Estuary based on data from HY-1C,which was launched in September 2018 in China,carrying Coastal Zone Imager(CZI)and Chinese Ocean Color and Temperature Scanner on it.A new SSC inversion model was established based on the relationship between in-situ SSC and the remote sensing reflectance in red and near-infrared bands of CZI image.HY-1C satellite data obtained from October to December 2019 were applied to retrieve SSC in the Zhujiang River Estuary.The results show that SSC around the HKZMB is ranging from 20 mg/L to 95 mg/L.SSC change obviously on two sides of the bridge.During flooding and ebbing period,SSC increases obviously downstream of the bridge.SSC difference between upstream and downstream is ranging from 5 mg/L to 20 mg/L.Currents flowing across the HKZMB,the change trend of SSC in most places upstream and downstream is almost the same that SSC downstream of the bridge is higher than SSC upstream.The tidal currents interact with bridge piers,inducing vortexes downstream,leading the sediment to re-suspend downstream of the bridge piers.Other factors,including seafloor topography and wind,can also contribute to the distribution of SSC in the Zhujiang River Estuary. 展开更多
关键词 HY-1C Coastal Zone imager(CZI) Hong Kong-Zhuhai-Macao Bridge suspended sediment content Zhujiang River Estuary
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China Receives Images From SuperView-1 被引量:1
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作者 GUO Wei 《Aerospace China》 2017年第1期62-63,共2页
Launched on December 28,2016,the Super View-1 satellite has operated for over 70 days at an altitude of 530km.The initial results of in-orbit commissioning show that the images from the Super View-1 satellite are clea... Launched on December 28,2016,the Super View-1 satellite has operated for over 70 days at an altitude of 530km.The initial results of in-orbit commissioning show that the images from the Super View-1 satellite are clear with radiation resolution reaching 11 bits pixel.The geospatial positioning accuracy without ground control pointing is5-8 m,the elevation relative accuracy is1 m.The maximum single scene can be60 km×70 km,enabling some 900。 展开更多
关键词 VIEW HIGH China Receives images From SuperView-1
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Image potential states mediated STM imaging of cobalt phthalocyanine on NaCl/Cu(100)
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作者 郭秦敏 秦志辉 +2 位作者 黄敏 Vladimir N.Mantsevich 曹更玉 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第3期314-318,共5页
The adsorption and electronic properties of isolated cobalt phthalocyanine (CoPc) molecule on an ultrathin layer of NaC1 have been investigated. High-resolution STM images give a detailed picture of the lowest unocc... The adsorption and electronic properties of isolated cobalt phthalocyanine (CoPc) molecule on an ultrathin layer of NaC1 have been investigated. High-resolution STM images give a detailed picture of the lowest unoccupied molecular orbital (LUMO) of an isolated CoPc. It is shown that the NaC1 ultrathin layer efficiently decouples the interaction of the molecules from the underneath metal substrate, which makes it an ideal substrate for studying the properties of single molecules. Moreover, strong dependence of the appearance of the molecules on the sample bias in the region of relatively high bias (〉 3.1 V) is ascribed to the image potential states (IPSs) of NaCI/Cu(100), which may provide us with a possible method to fabricate quantum storage devices. 展开更多
关键词 image potential states NaC1 ultrathin layer CoPc scanning tunneling microscopy
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A Cross-Plane Color Image Encryption Algorithm Based on 1D-SLM
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作者 Xiaohong Wang Huiqing Wu +1 位作者 Yuying Ma Shuzhen Huang 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期1093-1108,共16页
With the rapid development of 5G technology,it has become fast and easy for people to transmit information on the Internet.Digital images can express information more intuitively,so transmitting information through im... With the rapid development of 5G technology,it has become fast and easy for people to transmit information on the Internet.Digital images can express information more intuitively,so transmitting information through images has excellent applications.This paper uses a new chaotic system called 1D-Sin-Logistic-Map(1D-SLM).1D-SLM has two control parameters,which can provide larger parameter space,and the parameter space in the chaotic state is continuous.Through Lyapunov exponent analysis(LE),bifurcation diagrams analysis,spectral entropy analysis(SE),and 0-1 test,it is verified that 1D-SLM has complex dynamic behavior and is very suitable for cryptography.Compared with other 1D chaotic systems,the 1D-SLM has a larger Lyapunov exponent(LE)and spectral entropy(SE).For color image encryption algorithms,only relying on chaotic mapping is not enough to ensure security.So combined with 1D-SLM,we design a color image encryption algorithm,which is implemented by plane expansion,which reduces the correlation between the three channels of color images.The experimental results show that the proposed cross-plane color image encryption algorithm is safe and resistant to common attack methods. 展开更多
关键词 Chaos theory chaotic system 1D-SLM image encryption information security
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Extraction of Planting Information of Winter Wheat in a Province Based on GF-1/WFV Images
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作者 Li Feng Qin Quan +2 位作者 Wang Hao Hu Xianfeng Zhao Hong 《Meteorological and Environmental Research》 CAS 2018年第4期100-105,共6页
In order to explore the adaptability of domestic high-resolution GF-1 satellite images in the extraction of planting information of crops especially in a province, based on the 16-meter remote sensing images of a ... In order to explore the adaptability of domestic high-resolution GF-1 satellite images in the extraction of planting information of crops especially in a province, based on the 16-meter remote sensing images of a multi-spectral wide-spectrum camera (WFV) carried by the GF-1 satellite as well as land use type and field survey data of Shandong Province, the planting area and distribution regions of winter wheat in Shandong Province (the main producing area of winter wheat in China) in 2016 were extracted by decision tree classification method and supervised classification- maximum likelihood classification method, and the accuracy of the classification results was verified based on ground survey data and data published by the statistics bureau. The results showed that the method of taking the GF-1/WFV images as the main source of data, introducing multi-source information into the decision tree and supervised classification models, and then calculating the planting area of winter wheat in the province was feasible. The total accuracy of remote sensing interpretation of winter wheat in Shandong Province in 2016 reached 92.1 %, and Kappa coefficient was 0.806. The planting area of winter wheat extracted based on the remote sensing images in the province was slightly smaller than the area pro-vided by the statistics department, and the extraction accuracy of the area was 93.0%. Research indicates that GF-1/WFV images have great po-tential for development and application in remote sensing monitoring of planting information of crops in a province. 展开更多
关键词 GF-1/WFV images Winter wheat Provincial level Decision tree classification Supervised classification-maximum likelihood method
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Diffusion-weighted imaging and variable flip angle T1 mapping: a supplement for image-guided biopsy in follow-up analysis of liver fibrosis
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作者 Peng Hu Jihong Sun +8 位作者 Fangfang Lv Borui Pi Fangping Xu Guocan Han Xi Hu Yue Wang Ning Huang Xia Wu Xiaoming Yang 《Journal of Interventional Medicine》 2018年第3期150-156,共7页
Purpose To evaluate the performance of diffusion-weighted imaging(DWI) and variable flip angle(VFA) T1 mapping as a supplement to image-guided biopsy in follow-up analysis of liver fibrosis. Materials and Methods This... Purpose To evaluate the performance of diffusion-weighted imaging(DWI) and variable flip angle(VFA) T1 mapping as a supplement to image-guided biopsy in follow-up analysis of liver fibrosis. Materials and Methods This prospective study was approved by the institution's committee on human research, and written informed consent was provided from the enrolled patients. We investigated five MRI parameters of DWI and VFA T1 mapping, collected from 11 patients who underwent serial ultrasound image-guided biopsy with follow-up MRI within 1.5 years after treatment for liver fibrosis/cirrhosis. For each patient, four consecutive MRI examinations were conducted, including baseline MRI before treatment and three follow-up MRI examinations after treatment at each 0.5-year interval. ADC values at four b values and T1 relaxation times were correlated to pathology-confirmed liver fibrosis stages, which were subsequently divided into two groups, stages F2–3 and F4. The receiver operating characteristic(ROC) analysis and repeated measurement analysis of variance were used for statistical analysis. Results Among these ADC parameters, ADC value(b = 500 s/mm^2) was the most consistent in differentiating between stage F2–3 and F4 liver fibrosis. Repeated measurement analysis showed that the intra-group and inter-group differences were 0.447 and 0.024, respectively. T1 relaxation time could not consistently differentiate between the F2–3 and F4 groups; however, it was repeatable, and the intra-group and inter-group differences were 0.410 and 0.042, respectively. Conclusion MRI-ADC value at a b value of 500 s/mm^2 can be a promising biomarker for differentiating stages F2–3 and F4 liver fibrosis. A combination of this biomarker with repeatable T1 relaxation time may function as a non-invasive tool for follow-up liver fibrosis in patients who reject repeated image-guided biopsy. 展开更多
关键词 image-GUIDED biopsy MRI T1 MAPPING DIFFUSION-WEIGHTED imaging
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Assessment the Optimal Effect of Time of Repetition: Extrinsic Pulse Parameter on Gd-DTPA Enhanced, Spin-Echo T1-Weighted MR Images under Low Magnetic Field Strength
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作者 Bimali Sanjeevani Weerakoon Toshiaki Osuga Takehisa Konishi 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2016年第3期196-203,共9页
The contrast agent concentration, the time of repetition (TR) and magnetic field strength are significant parameters that influence for the accurate signal intensity (SI) in quantitative Magnetic Resonance Imaging (MR... The contrast agent concentration, the time of repetition (TR) and magnetic field strength are significant parameters that influence for the accurate signal intensity (SI) in quantitative Magnetic Resonance Imaging (MRI). Therefore, this study was conducted to investigate and refine the dependence and the optimal effect of Time of Repetition (TR) on the relationship between signal intensity and Gd-DTPA (Gadolinium-diethylene-triaminepenta-acetic acid) concentration, after applying two-dimensional (2D) Spin Echo (SE) pulse sequence under low-field MRI. In addition to that, the optimal concentration of Gd-DTPA at given sequence parameters at low-field MRI was also evaluated. A water-filled phantom was constructed for a range of Gd-DTPA concentrations (0 - 6 mmol/L) and the mean signal intensities (SIs) were assessed in the defined region of interest on T1-weighted images with different TR values (40 - 2000 ms). The generated signal-concentration curves for Gd-DTPA revealed that increasing TR was associated with the increase of the overall SIs and the maximum relationship between SI to concentration. Moreover, the required Gd-DTPA concentration to produce the maximum SI was associated to decrease with the increase of TR. In addition to this, the application of beyond 100 ms TR values in this study with relatively higher concentrations (beyond 1 - 2 mmol/L) has resulted predominantly non-linear patterns in the signal-concentration curves and it appears the saturation or decay of the SIs due to T2 effect. From these results, it can be suggested that the selection of relatively lower Gd-DTPA concentration ( mmol/L) with less than 800 ms (<800 ms) TR values can produce a better linear relationship between the concertation and SIs in T1-weighted SE low field contrast-enhanced MRI. Furthermore, this study also outlined the significance and necessity of the optimization of TR in SE sequence in low field MRI prior to a particular examination. 展开更多
关键词 Gd-DTPA Concentration Spin Echo Pulse Sequence Signal Intensity Time of Repetition T1-Weighted images Low Field MRI
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基于P5像对与GeoEye-1影像的近地表地层产状的提取 被引量:9
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作者 刘华国 冉勇康 +2 位作者 李安 徐良鑫 李峰 《地震地质》 EI CSCD 北大核心 2011年第4期951-962,共12页
通过对P5立体像对、GeoEye-1影像的处理与分析,分别进行了数字高程模型的提取和地层的划分,用检查点法和目视检查法对提取的数字高程模型的误差评估结果显示,误差在5m以内,满足产状提取的要求。根据地层划分结果,在不同时代的地层边界... 通过对P5立体像对、GeoEye-1影像的处理与分析,分别进行了数字高程模型的提取和地层的划分,用检查点法和目视检查法对提取的数字高程模型的误差评估结果显示,误差在5m以内,满足产状提取的要求。根据地层划分结果,在不同时代的地层边界处和同时代地层内部选择岩层三角面发育较好、产状相对稳定的区域,选取用于地层产状提取的点,并获取其三维坐标,然后在MATLAB环境下根据三点法或多点拟合法原理及公式编程提取地层产状。野外验证结果表明,提取的产状倾角误差均在6°以内,其中85%的误差在4°以内,中误差在3°以内,均在定量研究可接受的范围之内,并分析和总结了误差产生的主要原因。研究结果表明,利用P5立体像对与GeoEye-1影像提取近地表地层产状的方法,有效地约束了浅层构造的形态,减少了构造分析的不确定性,对柯坪的构造变形研究具有重要意义。 展开更多
关键词 P5立体像对 geoeye-1影像 数字高程模型 产状提取
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Geoeye-1全色与多光谱影像融合方法 被引量:11
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作者 杨智翔 徐佳 何秀凤 《光电工程》 CAS CSCD 北大核心 2011年第5期120-126,共7页
针对传统的像素级融合方法对高分辨力影像融合存在较大光谱扭曲的问题,在分析了Geoeye-1传感器光谱响应特性的基础上,提出了一种适合Geoeye-1全色与多光谱影像融合的高保真方法。本文所提的方法的改进之处主要体现在两个方面:低空间分... 针对传统的像素级融合方法对高分辨力影像融合存在较大光谱扭曲的问题,在分析了Geoeye-1传感器光谱响应特性的基础上,提出了一种适合Geoeye-1全色与多光谱影像融合的高保真方法。本文所提的方法的改进之处主要体现在两个方面:低空间分辨力全色影像的构建方式和空间细节信息注入系数的选取。利用澳大利亚霍巴特地区的Geoeye-1全色和多光谱影像进行了试验研究,从主观评价和定量分析综合评价了新方法与传统的影像融合方法的融合效果,结果表明新方法在光谱信息损失最少的情况下,较大地提高了影像的空间分辨力,与其他方法相比具有更好的综合性能。 展开更多
关键词 geoeye-1 全色影像 多光谱影像 光谱响应 影像融合
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基于分形理论与GEOEYE-1影像的NDVI连续空间尺度转换模型构建及应用 被引量:11
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作者 栾海军 田庆久 +2 位作者 顾行发 余涛 胡新礼 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2013年第6期538-544,549,共8页
基于GEOEYE-1多光谱影像、以归一化差分植被指数(NDVI)为研究对象继续就分形方法在高空间分辨率基础图影像中的适用性进行研究,并就分形模型构建最合理尺度层级的确定进行细致探讨.实验表明,基于分形理论的NDVI连续空间尺度转换模型构... 基于GEOEYE-1多光谱影像、以归一化差分植被指数(NDVI)为研究对象继续就分形方法在高空间分辨率基础图影像中的适用性进行研究,并就分形模型构建最合理尺度层级的确定进行细致探讨.实验表明,基于分形理论的NDVI连续空间尺度转换模型构建方法适用于高空间分辨率遥感影像;在给定的条件下,NDVI尺度转换分形模型构建时最合理尺度层级存在且可计算.研究使得分形方法所适用的反演量类型及基础图空间分辨率范围皆有大的扩展. 展开更多
关键词 定量遥感 尺度转换 分形 归一化差分植被指数(NDVI) geoeye-1 真实性检验
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基于GeoEye-1卫星影像的立体测图技术研究 被引量:10
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作者 张海涛 贾光军 虞欣 《测绘通报》 CSCD 北大核心 2010年第12期43-46,共4页
以某试验区的GeoEye-1卫星遥感影像、外业控制资料等数据为基础进行影像区域网平差解算,对平差精度进行分析,并通过部分试验区外业调绘来分析GeoEye-1卫星遥感影像是否满足国家相应规范中1∶10 000、1∶5 000以及1∶2 000地形图修测要求... 以某试验区的GeoEye-1卫星遥感影像、外业控制资料等数据为基础进行影像区域网平差解算,对平差精度进行分析,并通过部分试验区外业调绘来分析GeoEye-1卫星遥感影像是否满足国家相应规范中1∶10 000、1∶5 000以及1∶2 000地形图修测要求,最终形成基于GeoEye-1卫星遥感影像的立体测图生产工艺流程。 展开更多
关键词 卫星影像 地形图 立体测图 geoeye-1
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GeoEye-1立体像对定位精度分析及应用 被引量:5
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作者 胡珊 胡庆武 +2 位作者 程海帆 陶建斌 李凤尊 《地理空间信息》 2010年第4期13-15,19,共4页
对GeoEye-1立体定位模型进行初步研究,给出消除RPC模型系统误差的控制点选择和区域网平差方案。结合PixelGrid进行了基于不同布点方案下区域网平差实验,并和INOKOS定位精度进行对比分析。结果表明,加入少量控制点(1~9个)可明显消除RPC... 对GeoEye-1立体定位模型进行初步研究,给出消除RPC模型系统误差的控制点选择和区域网平差方案。结合PixelGrid进行了基于不同布点方案下区域网平差实验,并和INOKOS定位精度进行对比分析。结果表明,加入少量控制点(1~9个)可明显消除RPC模型系统误差,平面精度达到0.2~0.3m,高程精度达到0.5m,能满足公路勘测选线1∶2000测图要求,高分辨率正射影像和数字地面模型可直接用于公路勘测选线设计。 展开更多
关键词 geoeye-1 立体像对 定位精度 公路勘测
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Geoeye-1卫星立体像对处理试验 被引量:9
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作者 刘俊杰 贾永红 +1 位作者 何保国 张谦 《地理空间信息》 2010年第2期83-85,共3页
介绍基于LPS的立体像对处理流程,阐述通过ERDASLPS对Geoeye-1立体影像进行空中三角测量的方法。试验证明,利用少量控制点进行空三测量,其处理结果的几何精度较高并且完全可以满足1:5000及以下比例尺的各种测图要求。
关键词 遥感 geoeye-1 ERDAS LPS 精度评价
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