This paper proposed a novel fast fractional pixel search algorithm based on polynomial model. With the analysis of distribution characteristics of motion compensation error surface inside tractional pixel searching wi...This paper proposed a novel fast fractional pixel search algorithm based on polynomial model. With the analysis of distribution characteristics of motion compensation error surface inside tractional pixel searching window, the matching error is fitted with parabola along horizontal and vertical direction respectively. The proposcd searching strategy needs to check only 6 points rather than 16 or 24 points, which are used in the l lierarchical Fractional Pel Search algorithm （HFPS） for 1/4-pel and 1/8-pel Motion Estimation （ME）. The experimental results show that the proposed algorithm shows very good capability in keeping the rate distortion performance while reduces computation load to a large extent compared with HFPS algorithm.展开更多
By using the MOS-based model established in this paper, the physical process of photoelectron generation, transfer,and storage in the four-transistor active pixel sensor(4 T-APS) pixels can be simulated in SPICE envir...By using the MOS-based model established in this paper, the physical process of photoelectron generation, transfer,and storage in the four-transistor active pixel sensor(4 T-APS) pixels can be simulated in SPICE environment. The variable capacitance characteristics of double junctions in pinned photodiodes(PPDs) and the threshold voltage difference formed by channel nonuniform doping in transfer gates(TGs) are considered with this model. The charge transfer process of photogenerated electrons from PPDs to the floating diffusion(FD) is analyzed, and the function of nonuniform doping of TGs in suppressing charge injection back to PPDs is represented with the model. The optical and electrical characteristics of all devices in the pixel are effectively combined with the model. Moreover, the charge transfer efficiency and the voltage variation in PPD can be described with the model. Compared with the hybrid simulation in TCAD and the Verilog-A simulation in SPICE, this model has higher simulation efficiency and accuracy, respectively. The effectiveness of the MOS-based model is experimentally verified in a 3 μm test pixel designed in 0.11 μm CIS process.展开更多
MODIS （Moderate Resolution Imaging Spectroradiometer） is a key instrument aboard the Terra （EOS AM） and Aqua （EOS PM） satellites. Linear spectral mixture models are applied to MOIDS data for the sub-pixel classi...MODIS （Moderate Resolution Imaging Spectroradiometer） is a key instrument aboard the Terra （EOS AM） and Aqua （EOS PM） satellites. Linear spectral mixture models are applied to MOIDS data for the sub-pixel classification of land covers. Shaoxing county of Zhejiang Province in China was chosen to be the study site and early rice was selected as the study crop. The derived proportions of land covers from MODIS pixel using linear spectral mixture models were compared with unsupervised classification derived from TM data acquired on the same day, which implies that MODIS data could be used as satellite data source for rice cultivation area estimation, possibly rice growth monitoring and yield forecasting on the regional scale.展开更多
The objective of this paper is to improve the monitoring speed and precision of fractional vegetation cover (fc). It mainly focuses on fc estimation when fcmax and fcmin are not approximately equal to 100% and 0%, res...The objective of this paper is to improve the monitoring speed and precision of fractional vegetation cover (fc). It mainly focuses on fc estimation when fcmax and fcmin are not approximately equal to 100% and 0%, respectively due to using remote sensing image with medium or low spatial resolution. Meanwhile, we present a new method of fc estimation based on a random set of fc maximum and minimum values from digital camera (DC) survey data and a di- midiate pixel model. The results show that this is a convenient, efficient and accurate method for fc monitoring, with the maximum error -0.172 and correlation coefficient of 0.974 between DC survey data and the estimated value of the remote sensing model. The remaining DC survey data can be used as verification data for the precision of the fc estimation. In general, the estimation of fc based on DC survey data and a remote sensing model is a brand-new development trend and deserves further extensive utilization.展开更多
[Objective] The aim was to research soil erosion in boundary areas of Dongchuan City and Huize County in Yunnan Province through quantitative analysis on factors influencing soil erosion and establishment of conceptua...[Objective] The aim was to research soil erosion in boundary areas of Dongchuan City and Huize County in Yunnan Province through quantitative analysis on factors influencing soil erosion and establishment of conceptual model, providing method for land use and treatment of soil erosion. [Method] Based on Universal Soil Loss Equation （USLE）, quantitative indices determined and the conceptual model of of six factors influencing soil erosion were soil erosion was established. In addition. pixel-loss map was obtained through multiplication and soil erosive areas and the treatment schemes were proposed through statistical work of pixel-loss map and soil erosion map. [Result] In the research, annual loss modulus averaged 5 962 t/hm2, indicating the area was heavily eroded; from soil erosion map, it can be concluded that the heavily erosive area was near rivers, where wasteland and bare land dominated with slope of 30°-40° and without protective measures. [Conclusion] The research indicated that land use in the area is unreasonable erosive region should be paid more attention. In addition, the to be changed into terrace cultivation. and 51.6% of heavily wasteland is suggested to be changed into terrace cultivation.展开更多
Tracking and segmentation of moving objects are suffering from many problems including those caused by elimination changes, noise and shadows. A modified algorithm for the adaptive background model is proposed by link...Tracking and segmentation of moving objects are suffering from many problems including those caused by elimination changes, noise and shadows. A modified algorithm for the adaptive background model is proposed by linking Gaussian mixture model with the method of principal component analysis PCA. This approach utilizes the advantage of the PCA method in providing the projections that capture the most relevant pixels for segmentation within the background models. We report the update on both the parameters of the modified method and that of the Gaussian mixture model. The obtained results show the relatively outperform of the integrated method.展开更多
As a promising technique to enhance the spatial reso- lution of remote sensing imagery, sub-pixel mapping is processed based on the spatial dependence theory with the assumption that the land cover is spatially depend...As a promising technique to enhance the spatial reso- lution of remote sensing imagery, sub-pixel mapping is processed based on the spatial dependence theory with the assumption that the land cover is spatially dependent both within pixels and be- tween them. The spatial attraction is used as a tool to describe the dependence. First, the spatial attractions between pixels, sub- pixel/pixel spatial attraction model （SPSAM）, are described by the modified SPSAM （MSPSAM） that estimates the attractions accord- ing to the distribution of sub-pixels within neighboring pixels. Then a mixed spatial attraction model （MSAM） for sub-pixel mapping is proposed that integrates the spatial attractions both within pix- els and between them. According to the expression of the MSAM maximumising the spatial attraction, the genetic algorithm is em- ployed to search the optimum solution and generate the sub-pixel mapping results. Experiments show that compared with SPSAM, MSPSAM and pixel swapping algorithm modified by initialization from SPSAM （MPS）, MSAM can provide higher accuracy and more rational sub-pixel mapping results.展开更多
The intensity distribution in Fresnel diffraction through a slit includes numerous small fluctuations referred to as ripples. These ripples make the modelling of the intensity distribution complicated. In this study, ...The intensity distribution in Fresnel diffraction through a slit includes numerous small fluctuations referred to as ripples. These ripples make the modelling of the intensity distribution complicated. In this study, we examine the characteristics of the Fresnel diffraction intensity distribution to deduce the rule for the peak position and then propose two types of quantum-mathematical models to obtain the distance between the edge and the peak point. The analysis and simulation indicate that the error in the models is below 0.50 μm. The models can also be used to detect the edges of a diffraction object, and we conduct several experiments to measure the slit width. The experimental results reveal that the repetition accuracy of the method can reach 0.23 μm.展开更多
电子轰击有源像素传感器(electron bombardment active pixel sensor,EBAPS)的光响应非均匀性是指EBAPS中光电阴极被均匀光源照射时,不同像素输出灰度不一致的现象,尤其是在低光环境下,图像的非均匀性会使细节识别变得困难,影响后续图...电子轰击有源像素传感器(electron bombardment active pixel sensor,EBAPS)的光响应非均匀性是指EBAPS中光电阴极被均匀光源照射时,不同像素输出灰度不一致的现象,尤其是在低光环境下,图像的非均匀性会使细节识别变得困难,影响后续图像处理和分析的准确性。光响应非均匀性主要由光电阴极不同区域对光响应的差异、电子敏感互补金属氧化物半导体不同区域的电子倍增特性差异、各像素间对同一激励的响应差异以及读出电路中传输信道的差异性等因素导致。针对EBAPS的非均匀性问题,提出了一种基于EBAPS光电阴极响应、电子倍增以及像素响应非均匀性协同适配的测试方法。实验结果表明,该方法能够有效评价EBAPS的非均匀性,并且能够对器件的测试筛选和算法校正起到指导作用。展开更多
现有的异常检测方法能在特定应用场景下实现高精度检测,然而这些方法难以适用于其他应用场景,且自动化程度有限。因此,提出一种视觉基础模型(VFM)驱动的像素级图像异常检测方法SSMOD-Net(State Space Model driven-Omni Dimensional Ne...现有的异常检测方法能在特定应用场景下实现高精度检测,然而这些方法难以适用于其他应用场景,且自动化程度有限。因此,提出一种视觉基础模型(VFM)驱动的像素级图像异常检测方法SSMOD-Net(State Space Model driven-Omni Dimensional Net),旨在实现更精确的工业缺陷检测。与现有方法不同,SSMOD-Net实现SAM(Segment Anything Model)的自动化提示且不需要微调SAM,因此特别适用于需要处理大规模工业视觉数据的场景。SSMOD-Net的核心是一个新颖的提示编码器,该编码器由状态空间模型驱动,能够根据SAM的输入图像动态地生成提示。这一设计允许模型在保持SAM架构不变的同时,通过提示编码器引入额外的指导信息,从而提高检测精度。提示编码器内部集成一个残差多尺度模块,该模块基于状态空间模型构建,能够综合利用多尺度信息和全局信息。这一模块通过迭代搜索,在提示空间中寻找最优的提示,并将这些提示以高维张量的形式提供给SAM,从而增强模型对工业异常的识别能力。而且所提方法不需要对SAM进行任何修改,从而避免复杂的对训练计划的微调需求。在多个数据集上的实验结果表明,所提方法展现出了卓越的性能,与AutoSAM和SAM-EG(SAM with Edge Guidance framework for efficient polyp segmentation)等方法相比,所提方法在mE(mean E-measure)和平均绝对误差(MAE)、Dice和交并比(IoU)上都取得了较好的结果。展开更多
基金Supported by the Doctoral Foundation of Ministry of Education of China (No.20040699015).
文摘This paper proposed a novel fast fractional pixel search algorithm based on polynomial model. With the analysis of distribution characteristics of motion compensation error surface inside tractional pixel searching window, the matching error is fitted with parabola along horizontal and vertical direction respectively. The proposcd searching strategy needs to check only 6 points rather than 16 or 24 points, which are used in the l lierarchical Fractional Pel Search algorithm （HFPS） for 1/4-pel and 1/8-pel Motion Estimation （ME）. The experimental results show that the proposed algorithm shows very good capability in keeping the rate distortion performance while reduces computation load to a large extent compared with HFPS algorithm.
基金Project supported by the National Natural Science Foundation of China (Grant No. 61874085)the Postdoctoral Research Funding Project of Shaanxi Province,China (Grant No. 2018BSHEDZZ41)。
文摘By using the MOS-based model established in this paper, the physical process of photoelectron generation, transfer,and storage in the four-transistor active pixel sensor(4 T-APS) pixels can be simulated in SPICE environment. The variable capacitance characteristics of double junctions in pinned photodiodes(PPDs) and the threshold voltage difference formed by channel nonuniform doping in transfer gates(TGs) are considered with this model. The charge transfer process of photogenerated electrons from PPDs to the floating diffusion(FD) is analyzed, and the function of nonuniform doping of TGs in suppressing charge injection back to PPDs is represented with the model. The optical and electrical characteristics of all devices in the pixel are effectively combined with the model. Moreover, the charge transfer efficiency and the voltage variation in PPD can be described with the model. Compared with the hybrid simulation in TCAD and the Verilog-A simulation in SPICE, this model has higher simulation efficiency and accuracy, respectively. The effectiveness of the MOS-based model is experimentally verified in a 3 μm test pixel designed in 0.11 μm CIS process.
文摘MODIS （Moderate Resolution Imaging Spectroradiometer） is a key instrument aboard the Terra （EOS AM） and Aqua （EOS PM） satellites. Linear spectral mixture models are applied to MOIDS data for the sub-pixel classification of land covers. Shaoxing county of Zhejiang Province in China was chosen to be the study site and early rice was selected as the study crop. The derived proportions of land covers from MODIS pixel using linear spectral mixture models were compared with unsupervised classification derived from TM data acquired on the same day, which implies that MODIS data could be used as satellite data source for rice cultivation area estimation, possibly rice growth monitoring and yield forecasting on the regional scale.
基金Projects NCET-04-0484 supported by the New-Century Outstanding Young Scientist Program from the Ministry of Education and D0605046040191-101Beijing Science and Technology Program
文摘The objective of this paper is to improve the monitoring speed and precision of fractional vegetation cover (fc). It mainly focuses on fc estimation when fcmax and fcmin are not approximately equal to 100% and 0%, respectively due to using remote sensing image with medium or low spatial resolution. Meanwhile, we present a new method of fc estimation based on a random set of fc maximum and minimum values from digital camera (DC) survey data and a di- midiate pixel model. The results show that this is a convenient, efficient and accurate method for fc monitoring, with the maximum error -0.172 and correlation coefficient of 0.974 between DC survey data and the estimated value of the remote sensing model. The remaining DC survey data can be used as verification data for the precision of the fc estimation. In general, the estimation of fc based on DC survey data and a remote sensing model is a brand-new development trend and deserves further extensive utilization.
文摘[Objective] The aim was to research soil erosion in boundary areas of Dongchuan City and Huize County in Yunnan Province through quantitative analysis on factors influencing soil erosion and establishment of conceptual model, providing method for land use and treatment of soil erosion. [Method] Based on Universal Soil Loss Equation （USLE）, quantitative indices determined and the conceptual model of of six factors influencing soil erosion were soil erosion was established. In addition. pixel-loss map was obtained through multiplication and soil erosive areas and the treatment schemes were proposed through statistical work of pixel-loss map and soil erosion map. [Result] In the research, annual loss modulus averaged 5 962 t/hm2, indicating the area was heavily eroded; from soil erosion map, it can be concluded that the heavily erosive area was near rivers, where wasteland and bare land dominated with slope of 30°-40° and without protective measures. [Conclusion] The research indicated that land use in the area is unreasonable erosive region should be paid more attention. In addition, the to be changed into terrace cultivation. and 51.6% of heavily wasteland is suggested to be changed into terrace cultivation.
文摘Tracking and segmentation of moving objects are suffering from many problems including those caused by elimination changes, noise and shadows. A modified algorithm for the adaptive background model is proposed by linking Gaussian mixture model with the method of principal component analysis PCA. This approach utilizes the advantage of the PCA method in providing the projections that capture the most relevant pixels for segmentation within the background models. We report the update on both the parameters of the modified method and that of the Gaussian mixture model. The obtained results show the relatively outperform of the integrated method.
基金supported by the National Natural Science Foundation of China (60802059)the Foundation for the Doctoral Program of Higher Education of China (200802171003)
文摘As a promising technique to enhance the spatial reso- lution of remote sensing imagery, sub-pixel mapping is processed based on the spatial dependence theory with the assumption that the land cover is spatially dependent both within pixels and be- tween them. The spatial attraction is used as a tool to describe the dependence. First, the spatial attractions between pixels, sub- pixel/pixel spatial attraction model （SPSAM）, are described by the modified SPSAM （MSPSAM） that estimates the attractions accord- ing to the distribution of sub-pixels within neighboring pixels. Then a mixed spatial attraction model （MSAM） for sub-pixel mapping is proposed that integrates the spatial attractions both within pix- els and between them. According to the expression of the MSAM maximumising the spatial attraction, the genetic algorithm is em- ployed to search the optimum solution and generate the sub-pixel mapping results. Experiments show that compared with SPSAM, MSPSAM and pixel swapping algorithm modified by initialization from SPSAM （MPS）, MSAM can provide higher accuracy and more rational sub-pixel mapping results.
基金Project supported by the National Natural Science Foundation of China(Grant No.61475018)
文摘The intensity distribution in Fresnel diffraction through a slit includes numerous small fluctuations referred to as ripples. These ripples make the modelling of the intensity distribution complicated. In this study, we examine the characteristics of the Fresnel diffraction intensity distribution to deduce the rule for the peak position and then propose two types of quantum-mathematical models to obtain the distance between the edge and the peak point. The analysis and simulation indicate that the error in the models is below 0.50 μm. The models can also be used to detect the edges of a diffraction object, and we conduct several experiments to measure the slit width. The experimental results reveal that the repetition accuracy of the method can reach 0.23 μm.
文摘电子轰击有源像素传感器(electron bombardment active pixel sensor,EBAPS)的光响应非均匀性是指EBAPS中光电阴极被均匀光源照射时,不同像素输出灰度不一致的现象,尤其是在低光环境下,图像的非均匀性会使细节识别变得困难,影响后续图像处理和分析的准确性。光响应非均匀性主要由光电阴极不同区域对光响应的差异、电子敏感互补金属氧化物半导体不同区域的电子倍增特性差异、各像素间对同一激励的响应差异以及读出电路中传输信道的差异性等因素导致。针对EBAPS的非均匀性问题,提出了一种基于EBAPS光电阴极响应、电子倍增以及像素响应非均匀性协同适配的测试方法。实验结果表明,该方法能够有效评价EBAPS的非均匀性,并且能够对器件的测试筛选和算法校正起到指导作用。
文摘现有的异常检测方法能在特定应用场景下实现高精度检测,然而这些方法难以适用于其他应用场景,且自动化程度有限。因此,提出一种视觉基础模型(VFM)驱动的像素级图像异常检测方法SSMOD-Net(State Space Model driven-Omni Dimensional Net),旨在实现更精确的工业缺陷检测。与现有方法不同,SSMOD-Net实现SAM(Segment Anything Model)的自动化提示且不需要微调SAM,因此特别适用于需要处理大规模工业视觉数据的场景。SSMOD-Net的核心是一个新颖的提示编码器,该编码器由状态空间模型驱动,能够根据SAM的输入图像动态地生成提示。这一设计允许模型在保持SAM架构不变的同时,通过提示编码器引入额外的指导信息,从而提高检测精度。提示编码器内部集成一个残差多尺度模块,该模块基于状态空间模型构建,能够综合利用多尺度信息和全局信息。这一模块通过迭代搜索,在提示空间中寻找最优的提示,并将这些提示以高维张量的形式提供给SAM,从而增强模型对工业异常的识别能力。而且所提方法不需要对SAM进行任何修改,从而避免复杂的对训练计划的微调需求。在多个数据集上的实验结果表明,所提方法展现出了卓越的性能,与AutoSAM和SAM-EG(SAM with Edge Guidance framework for efficient polyp segmentation)等方法相比,所提方法在mE(mean E-measure)和平均绝对误差(MAE)、Dice和交并比(IoU)上都取得了较好的结果。
