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Saturation correction and effi cient discrimination methods for low-resistivity sandstone oil reservoirs
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作者 Jin Li-zuan 《Applied Geophysics》 2025年第2期319-330,556,共13页
This study discusses the challenges in logging the evaluation of low-resistivity oil reservoirs,especially the difficult problems involving their saturation calculation.A correction method for equivalent water conduct... This study discusses the challenges in logging the evaluation of low-resistivity oil reservoirs,especially the difficult problems involving their saturation calculation.A correction method for equivalent water conductivity is proposed,given the high conductivity caused by small amounts of water distributed in a network within the low-resistivity reservoir,which mimics the eff ects of high water saturation.This approach signifi cantly improves the accuracy of hydrocarbon saturation calculations in these low-resistivity reservoirs.The corrected hydrocarbon saturation values highly matched the porosity and are consistent with experimental results.This study also establishes a discrimination process to determine whether corrections are required,verifying the eff ectiveness and accuracy of the method through an application example. 展开更多
关键词 low-resistivity oil reservoirs saturation correction equivalent water conductivity discriminant methods
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A high-accuracy particle-type labeling method for organic scintillator pulse waveform datasets
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作者 Lin-Jun Hou Peng Xu +1 位作者 Zhi-Meng Hu Jie Cheng 《Nuclear Science and Techniques》 2026年第2期143-155,共13页
The pulse shape discrimination technique plays a pivotal role in neutron field measurements using organic scintillator detectors,and the particle-type labeling accuracy of the pulse waveform dataset has a significant ... The pulse shape discrimination technique plays a pivotal role in neutron field measurements using organic scintillator detectors,and the particle-type labeling accuracy of the pulse waveform dataset has a significant impact on its performance,especially with the growing use of machine learning methods.In this study,a high-accuracy labeling method for pulse waveform datasets based on the time-of-flight(TOF)filtering method,an improved charge comparison method(CCM),and the coincidence measurement method is proposed.The relationship between the experimental parameters and the chance coincidence proportion in the TOF measurement was derived to reduce contamination from chance coincidences at the experimental level.Based on this,an experiment was conducted to obtain raw data using the^(241)AmBe source,and a piled-up identification algorithm based on reference waveform cross-correlation and differential analysis was designed to filter out piled-up pulses.To improve the labeling accuracy,the CCM was optimized,a simple method of selecting the TOF interval for a lower chance coincidence proportion was proposed,and a low-amplitude pulse waveform dataset construction method based on coincidence measurements was developed.To verify these methods,eight pulse waveform datasets were constructed using different combinations of the proposed approaches.Three neural network structures and a corresponding evaluation parameter were designed to test the quality of these datasets.The results showed that the particle identification performance of the CCM was significantly improved after optimization,with the neutron-to-gamma-ray misidentification rate reduced by more than 35%.The proposed accuracy improvement methods reduced ambiguous identification results from these artificial neural networks by more than 50%. 展开更多
关键词 Pulse shape discrimination Organic liquid scintillator Time of flight Charge comparison method Machine learning
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Kernel Model Applied in Kernel Direct Discriminant Analysis for the Recognition of Face with Nonlinear Variations 被引量:1
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作者 李粉兰 徐可欣 《Transactions of Tianjin University》 EI CAS 2006年第2期147-152,共6页
A kernel-based discriminant analysis method called kernel direct discriminant analysis is employed, which combines the merit of direct linear discriminant analysis with that of kernel trick. In order to demonstrate it... A kernel-based discriminant analysis method called kernel direct discriminant analysis is employed, which combines the merit of direct linear discriminant analysis with that of kernel trick. In order to demonstrate its better robustness to the complex and nonlinear variations of real face images, such as illumination, facial expression, scale and pose variations, experiments are carried out on the Olivetti Research Laboratory, Yale and self-built face databases. The results indicate that in contrast to kernel principal component analysis and kernel linear discriminant analysis, the method can achieve lower (7%) error rate using only a very small set of features. Furthermore, a new corrected kernel model is proposed to improve the recognition performance. Experimental results confirm its superiority (1% in terms of recognition rate) to other polynomial kernel models. 展开更多
关键词 face recognition kernel method kernel direct discriminant analysis direct linear discriminant analysis
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Application of Fisher method to discriminating earthquakes and explosions using criterion m_b/M_S
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作者 边银菊 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2005年第4期441-450,共10页
We try to give a quantitative and global discrimination function by studying mb/MS data using Fisher method that is a kind of pattern recognition methods. The reliability of the function is also analyzed. The results ... We try to give a quantitative and global discrimination function by studying mb/MS data using Fisher method that is a kind of pattern recognition methods. The reliability of the function is also analyzed. The results show that this criterion works well and has a global feature, which can be used as first-level filtering criterions in event identification. The quantitative and linear discrimination function makes it possible to identify events automatically and achieve the goal to react the events quickly and effectively. 展开更多
关键词 mb/MS Fisher method seismological criterion pattern recognition discrimination efficiency
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基于高效液相色谱多指标成分分析的化学计量学评价补气养血颗粒质量
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作者 陈瑱 魏谭军 +3 位作者 陈飞 王春龙 魏旭 赵圣艳 《中国药业》 2026年第3期85-90,共6页
目的建立同时测定补气养血颗粒中14种成分含量的高效液相色谱法,并评价其质量。方法色谱柱为Prep Scalar C_(18)柱(250mm×4.6 mm,5μm),流动相为乙腈-0.2%磷酸溶液(梯度洗脱),流速为1.0 mL/min,检测波长分别为230 nm(芍药内酯苷、... 目的建立同时测定补气养血颗粒中14种成分含量的高效液相色谱法,并评价其质量。方法色谱柱为Prep Scalar C_(18)柱(250mm×4.6 mm,5μm),流动相为乙腈-0.2%磷酸溶液(梯度洗脱),流速为1.0 mL/min,检测波长分别为230 nm(芍药内酯苷、芍药苷、苯甲酰芍药苷)、210 nm(梓醇、地黄苷D、人参皂苷Rg_(1)、人参皂苷Re、人参皂苷Rb_(1))、260 nm(毛蕊异黄酮葡萄糖苷、芒柄花苷、黄芪紫檀烷苷)、280 nm(洋川芎内酯H、洋川芎内酯I、洋川芎内酯A),柱温为30℃,进样量为10μL。采用主成分分析(PCA)法和正交偏最小二乘法-判别分析(OPLS-DA)法筛选差异标志物,并采用加权逼近理想解排序(TOPSIS)法评价样品质量。结果上述14种成分在各自质量浓度范围内与峰面积线性关系良好(r≥0.9991,n=6);精密度、稳定性、重复性试验结果的RSD均小于2%;回收率为96.83%~100.18%,RSD为0.69%~1.82%(n=9)。18批样品中上述14种成分的含量分别为0.370~0.630 mg/g、0.630~1.080 mg/g、0.045~0.089 mg/g、0.260~0.500 mg/g、0.070~0.150 mg/g、0.150~0.260 mg/g、0.300~0.520 mg/g、0.150~0.440 mg/g、0.075~0.270 mg/g、0.060~0.101 mg/g、0.021~0.037 mg/g、0.035~0.059 mg/g、0.079~0.160 mg/g、0.220~0.380 mg/g。PCA和OPLS-DA结果显示,18批样品聚为3类,芍药苷、洋川芎内酯I、人参皂苷Rb_(1)、地黄苷D、梓醇、芍药内酯苷、人参皂苷Re、毛蕊异黄酮葡萄糖苷是影响样品质量的差异标志物。18批样品的相对贴近度(C_(i))为0.3210~0.7342,其中6批样品的C_(i)>0.5。结论该方法操作简便,结果科学、直观,可用于补气养血颗粒质量的综合评价。不同批次样品的质量存在一定差异。 展开更多
关键词 补气养血颗粒 高效液相色谱法 主成分分析 正交偏最小二乘法-判别分析 加权逼近理想解排序 质量评价
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基于光谱分析的电压互感器运行状态研判方法
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作者 石小帅 冯再均 +3 位作者 胡全贵 王轩 贺银志 姚金男 《高压电器》 北大核心 2026年第1期120-126,共7页
以确保电力系统稳定运行为目的,研究基于光谱分析的电压互感器运行状态研判方法,提升运行状态研判效果。激光拉曼光谱检测平台依据拉曼散射原理,获取电压互感器绝缘油拉曼谱线强度,按照拉曼谱线强度,绘制电压互感器绝缘油拉曼光谱,完成... 以确保电力系统稳定运行为目的,研究基于光谱分析的电压互感器运行状态研判方法,提升运行状态研判效果。激光拉曼光谱检测平台依据拉曼散射原理,获取电压互感器绝缘油拉曼谱线强度,按照拉曼谱线强度,绘制电压互感器绝缘油拉曼光谱,完成电压互感器内绝缘油拉曼光谱数据采集;通过迭代多项式拟合算法,预处理电压互感器绝缘油拉曼光谱;利用主成分分析法在预处理的拉曼光谱内,提取电压互感器绝缘油拉曼谱线强度特征;利用核Fisher判别分析法,建立电压互感器运行状态研判模型,在该模型内输入拉曼谱线强度特征,输出电压互感器运行状态研判结果。实验证明:该方法可有效采集电压互感器拉曼光谱,并预处理拉曼光谱;该方法可有效提取拉曼光谱特征,完成电压互感器运行状态研判;在研判不同类型运行状态时,该方法研判的Kappa系数均较高,即研判结果与实际结果间具备较优的一致性。 展开更多
关键词 光谱分析 电压互感器 运行状态 研判方法 拉曼散射 核FISHER判别
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我国大学教师招聘中的第一学历效应——来自简历大数据的测度分析
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作者 王思宇 刘进 《苏州大学学报(教育科学版)》 北大核心 2026年第1期107-119,共13页
科学公正的教师招聘事关高校人事民主和学术生态健康。利用ORCID全球学者简历库筛选出13178条中国学者样本,实证测度了我国大学教师初职招聘市场的第一学历效应。研究发现,精英院校新职教师的本科背景更加精英化。在控制相关履历特征情... 科学公正的教师招聘事关高校人事民主和学术生态健康。利用ORCID全球学者简历库筛选出13178条中国学者样本,实证测度了我国大学教师初职招聘市场的第一学历效应。研究发现,精英院校新职教师的本科背景更加精英化。在控制相关履历特征情况下,本科院校排名仍显著预测大学教师初职院校排名,该效应在不同年代(2000—2023年)、排除极端情况和延展到二次就业后依然稳健。PSM结果也显示“双一流”本科背景和“金本”出身均具有显著初职优势。但第一学历效应尚难推断为就业歧视。不同院校新职教师的博士学历同样层化明显。在同一回归模型中,其他履历特征也会影响教师初职结果。第一学历效应在不同院系和院校招聘方,以及不同应聘人群中均出现分化,削弱了总体效应。各方仍须警惕第一学历效应演化为就业歧视,高校招聘主体应加快人才评估体系建设,摆脱单一信号依赖;青年博士应防止第一学历效应的“自我实现”,增强学术资本积累。 展开更多
关键词 高校教师招聘 第一学历效应 就业歧视 大数据 简历分析法
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整数积阵的斜整除、拟斜整除及其应用
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作者 徐斌 商宇 邓勇 《高师理科学刊》 2026年第1期1-4,共4页
给出整数积阵、斜整除、拟斜整除等概念,证明了关于素因数的斜整除等价于整除及拟斜整除必定整除等结论。给出Gauss引理新的证明方法,推广Eisenstein判别法,并且给出Eisenstein判别法推广定理的两个应用实例。
关键词 整数积阵 斜整除性 拟斜整除 高斯引理 艾森斯坦因判别法
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A new method of formation evaluation for fractured and caved carbonate reservoirs:A case study from the Lundong area,Tarim Basin,China 被引量:7
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作者 Yang Haijun Sam Zandong Sun +4 位作者 Cai Lulu Xiao Youjun WangHaiyang Luo Chunshu Hu Hongru 《Petroleum Science》 SCIE CAS CSCD 2011年第4期446-454,共9页
The carbonate reservoirs in the Tarim Basin are characterized by low matrix-porosity,heterogeneity and anisotropy,which make it difficult to predict and evaluate these reservoirs.The reservoir formations in Lundong ar... The carbonate reservoirs in the Tarim Basin are characterized by low matrix-porosity,heterogeneity and anisotropy,which make it difficult to predict and evaluate these reservoirs.The reservoir formations in Lundong area experienced a series of diagenesis and tectonic evolution stages.And secondary storage spaces such as fractures and dissolution caves were developed while nearly all the primary pores have disappeared.Based on a summary of different types of storage spaces and their responses in conventional logs,FMI and full waveform sonic logs which are sensitive to different reservoirs,the comprehensive probability index (CPI) method is applied to evaluating the reservoirs and a standard of reservoir classification is established.By comparing the evaluation results with actual welllogging results,the method has proven to be practical for formation evaluation of carbonate reservoirs,especially for the fractured carbonate reservoirs.In reservoir fluid identification,the multivariate stepwise discriminant analysis (MSDA) method is introduced.Combining the CPI method and MSDA method,comprehensive formation evaluation has been performed for fractured and caved carbonate reservoirs in the Tarim Basin.Additionally,on the basis of secondary pore inversion results,another new method of formation evaluation is also proposed in the discussion part of this paper.Through detailed application result analysis,the method shows a promising capability for formation evaluation of complex carbonate reservoirs dominated by various secondary pores such as holes,caves,and cracks. 展开更多
关键词 Carbonate reservoir formation evaluation comprehensive probability index method discriminant analysis Tarim Basin
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Using Different Standardized Methods for Species Identification:A Case Study Using Beaks from Three Ommastrephid Species 被引量:4
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作者 HU Guanyu FANG Zhou +3 位作者 LIU Bilin CHEN Xinjun STAPLES Kevin CHEN Yong 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第2期355-362,共8页
The cephalopod beak is a vital hard structure with a stable configuration and has been widely used for the identification of cephalopod species. This study was conducted to determine the best standardization method fo... The cephalopod beak is a vital hard structure with a stable configuration and has been widely used for the identification of cephalopod species. This study was conducted to determine the best standardization method for identifying different species by measuring 12 morphological variables of the beaks of Illex argentinus, Ommastrephes bartramii, and Dosidicus gigas that were collected by Chinese jigging vessels. To remove the effects of size, these morphometric variables were standardized using three methods. The average ratios of the upper beak morphological variables and upper crest length of O. bartramii and D. gigas were found to be greater than those of I. argentinus. However, for lower beaks, only the average of LRL(lower rostrum length)/LCL(lower crest length), LRW(lower rostrum width)/LCL, and LLWL(lower lateral wall length)/LCL of O. bartramii and D. gigas were greater than those of I. argentinus. The ratios of beak morphological variables and crest length were found to be all significantly different among the three species(P < 0.001). Among the three standardization methods, the correct classification rate of stepwise discriminant analysis(SDA) was the highest using the ratios of beak morphological variables and crest length. Compared with hood length, the correct classification rate was slightly higher when using beak variables standardized by crest length using an allometric model. The correct classification rate of the lower beak was also found to be greater than that of the upper beak. This study indicates that the ratios of beak morphological variables to crest length could be used for interspecies and intraspecies identification. Meanwhile, the lower beak variables were found to be more effective than upper beak variables in classifying beaks found in the stomachs of predators. 展开更多
关键词 BEAK standardized methodS discriminant analysis Illex argentinus Ommastrephes bartramii Dosidicus GIGAS
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Program evaluation and its application to equipment based on super-efficiency DEA and gray relation projection method 被引量:5
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作者 Linbing Tang Dong Guo +1 位作者 Jie Wu Qingmei Tan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期1037-1042,共6页
For the gray attributes of the equipment program and its difficulty to carry out the quantitative assessment of the equipment program information, the gray relation projection method is simply reviewed. Combining the ... For the gray attributes of the equipment program and its difficulty to carry out the quantitative assessment of the equipment program information, the gray relation projection method is simply reviewed. Combining the super-data envelopment analysis(DEA) model and the gray system theory, a new super-DEA for measuring the weight is proposed, and a gray relation projection model is established to rank the equipment programs. Finally, this approach is used to evaluate the equipment program. The results are verified valid and can provide a new way for evaluating the equipment program. 展开更多
关键词 index weight discriminate coefficient gray relation projection method program evaluation
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Extended Fan's Algebraic Method and Its Application to KdV and Variant Boussinesq Equations 被引量:7
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作者 YANG Xian-Lin TANG Jia-Sh 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第7期1-6,共6页
An extended Fan's algebraic method is used for constructing exact traveling wave solution of nonlinearpartial differential equations.The key idea of this method is to introduce an auxiliary ordinary differential e... An extended Fan's algebraic method is used for constructing exact traveling wave solution of nonlinearpartial differential equations.The key idea of this method is to introduce an auxiliary ordinary differential equationwhich is regarded as an extended elliptic equation and whose degreeΥis expanded to the case of r>4.The efficiency ofthe method is demonstrated by the KdV equation and the variant Boussinesq equations.The results indicate that themethod not only offers all solutions obtained by using Fu's and Fan's methods,but also some new solutions. 展开更多
关键词 algebraic method KdV equation variant boussinesq equations polynomial complete discrimination system
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A New Discriminating Experiment on the Invariance Hypothesis of Light Speed 被引量:1
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作者 Jinxi Dong (Beijing Petrochemical College, Daxing, Beijing 102600, People’s Repulic of China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第4期137-146,共10页
This thesis puts forward a conjecture that, owing to some unknown special character of light, it is impossible to determine whether the speed of light is variable by the interference method. To verify the hypothesis ... This thesis puts forward a conjecture that, owing to some unknown special character of light, it is impossible to determine whether the speed of light is variable by the interference method. To verify the hypothesis of the invariance of light speed, a new method must be found to take accurate measurement of the infinitesimal change in the travelling time of light. The thesis suggests the adoption of high frequency laser pulse technology to carry out the measurement. On the basis of this idea a new discriminating experiment is proposed to test the hypothesis of the invariance of light speed. The thesis also makes some forecast of the future prospects of this experiment and of the future development of the theory of special relativity. 展开更多
关键词 Invariance of the speed of light Light pulse method CONJECTURE discriminating experiment.
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Trial Equation Method for Solving the Improved Boussinesq Equation 被引量:1
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作者 Yang Li 《Advances in Pure Mathematics》 2014年第2期47-52,共6页
Trial equation method is a powerful tool for obtaining exact solutions of nonlinear differential equations. In this paper, the improved Boussinesq is reduced to an ordinary differential equation under the travelling w... Trial equation method is a powerful tool for obtaining exact solutions of nonlinear differential equations. In this paper, the improved Boussinesq is reduced to an ordinary differential equation under the travelling wave transformation. Trial equation method and the theory of complete discrimination system for polynomial are used to establish exact solutions of the improved Boussinesq equation. 展开更多
关键词 The Nonlinear Partial Differential EQUATION Complete discrimination System for Polynomial TRIAL EQUATION method Traveling Wave Transform The IMPROVED BOUSSINESQ EQUATION
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Analyses on normal background characteristics about deformation observation data on the basis of wavelet transform method
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作者 李杰 刘希强 +2 位作者 李红 毛玉华 郑树田 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2005年第1期34-42,124,共10页
Wavelet transform method is applied to measure time-frequency distribution characteristics of digital deformation data and noise. Based on the characteristics of primary modulus and stochastic white noise discriminati... Wavelet transform method is applied to measure time-frequency distribution characteristics of digital deformation data and noise. Based on the characteristics of primary modulus and stochastic white noise discrimination factor of wavelet decomposition, we analyze the variation rule of normal background and noise data from Shandong digital deformation observation data. The research results indicate that: a) 1/4 daily wave, semi-diurnal tide wave, daily wave and half lunar wave and so on quasi-periodic signal exist in the detail decomposing signal of wavelet when scale are equal to 2, 3 and 4; b) The amplitude of detail decomposing signal is the biggest when scale is equal to 3; c) The detail decomposing signal contains mainly noise corresponding to scale 1 and 5, respectively; d) We may trace the abnormal precursory which is related to earthquake by analyzing non-earthquake wavelet decomposing signal whose scale is specified from digital deformation observation data. 展开更多
关键词 wavelet transform digital deformation observation data separation method between signal and noise discrimination of earthquake precursory
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Application of Trial Equation Method for Solving the Getmanou Equation
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作者 Li Yang 《Applied Mathematics》 2014年第10期1463-1473,共11页
Under the travelling wave transformation, some nonlinear partial differential equations such as the Getmanou equation are transformed to ordinary differential equation. Then using trial equation method and combing com... Under the travelling wave transformation, some nonlinear partial differential equations such as the Getmanou equation are transformed to ordinary differential equation. Then using trial equation method and combing complete discrimination system for polynomial, the classifications of all single traveling wave solution to this equation are obtained. 展开更多
关键词 trialequation method the Getmanou EQUATION complete discriminATION system for POLYNOMIAL the nonlinear partial differential EQUATION TRAVELING wave transform
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A New Shadow Removal Method for Color Images
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作者 Qiang He Chee-Hung Henry Chu 《Advances in Remote Sensing》 2013年第2期77-84,共8页
Shadow and variable illumination considerably influence the results of image understanding such as image segmentation, object tracking, and object recognition. The intrinsic image decomposition is to separate the refl... Shadow and variable illumination considerably influence the results of image understanding such as image segmentation, object tracking, and object recognition. The intrinsic image decomposition is to separate the reflectance and the illumination image from an observed image. The intrinsic image decomposition is very useful to remove shadows and then improve the performance of image understanding. In this paper, we present a new shadow removal method based on intrinsic image decomposition on a single color image using the Fisher Linear Discriminant (FLD). Under the assumptions-Lambertian surfaces, approximately Planckian lighting, and narrowband camera sensors, there exist an invariant image, which is 1-dimensional greyscale and independent of illuminant color and intensity. The Fisher Linear Discriminant is applied to create the invariant image. And further the shadows can be removed through the difference between invariant image and original color image. The experimental results on real data show good performance of this algorithm. 展开更多
关键词 INTRINSIC IMAGE Reflectance IMAGE Illumination IMAGE SHADOW Removal INVARIANT Direction K-Means method FISHER Linear discriminant
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Application of Trial Equation Method for Solving the Benjamin Ono Equation
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作者 Yang Li 《Journal of Applied Mathematics and Physics》 2014年第3期45-49,共5页
In the article, the nonlinear equation is reduced to an ordinary differential equation under the travelling wave transformation. Using trial equation method, the ODE is reduced to the elementary integral form. In the ... In the article, the nonlinear equation is reduced to an ordinary differential equation under the travelling wave transformation. Using trial equation method, the ODE is reduced to the elementary integral form. In the end, complete discrimination system for polynomial is used to solve the corresponding integrals and obtain the classification of all single travelling wave solutions to the equation. 展开更多
关键词 The Nonlinear Partial Differential EQUATION Complete discrimination System for POLYNOMIAL TRIAL EQUATION method TRAVELING Wave Transform The BENJAMIN Ono EQUATION
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Principal Component-Discrimination Model and Its Application
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作者 韩天锡 魏雪丽 +1 位作者 蒋淳 张玉琍 《Transactions of Tianjin University》 EI CAS 2004年第4期315-318,共4页
Having researched for many years, seismologists in China presented about 80 earthquake prediction factors which reflected omen information of earthquake. How to concentrate the information that the 80 earthquake predi... Having researched for many years, seismologists in China presented about 80 earthquake prediction factors which reflected omen information of earthquake. How to concentrate the information that the 80 earthquake prediction factors have and how to choose the main factors to predict earthquakes precisely have become one of the topics in seismology. The model of principal component-discrimination consists of principal component analysis, correlation analysis, weighted method of principal factor coefficients and Mahalanobis distance discrimination analysis. This model combines the method of maximization earthquake prediction factor information with the weighted method of principal factor coefficients and correlation analysis to choose earthquake prediction variables, applying Mahalanobis distance discrimination to establishing earthquake prediction discrimination model. This model was applied to analyzing the earthquake data of Northern China area and obtained good prediction results. 展开更多
关键词 principal component analysis discrimination analysis correlation analysis weighted method of principal factor coefficients
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粮食气味物质的提取、关键组分判别及其在储藏中的应用研究进展
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作者 李慧 洪习文 +1 位作者 王争艳 王艳艳 《食品科学》 EI CAS 北大核心 2025年第1期266-273,共8页
粮食气味物质受粮食种类、储藏条件、储藏时间及是否受有害生物污染等多种因素影响,气味物质种类及含量能够及时反映粮食是否变质或受有害生物危害。首先,本文概述目前常用的粮食气味物质的提取和鉴定技术,总结不同状态粮食气味物质组成... 粮食气味物质受粮食种类、储藏条件、储藏时间及是否受有害生物污染等多种因素影响,气味物质种类及含量能够及时反映粮食是否变质或受有害生物危害。首先,本文概述目前常用的粮食气味物质的提取和鉴定技术,总结不同状态粮食气味物质组成,发现烷烃类、酸类、醛类和醇类等物质赋予粮食特有的气味,而不同的储藏环境和粮食状态下,其气味物质存在较大差异。其次,探讨粮食中特征气味物质的分析方法,梳理粮食关键气味物质可能的代谢途径,归纳水稻和小麦中特征气味物质,其中稻谷中特征气味物质2-乙酰基-1-吡咯啉的生成机制也已得到初步确认。最后,对气味物质在粮食安全储藏领域的应用进行概述,提出深入分析、挖掘粮食气味物质数据,构建新型预测模型以快速、精准检测粮食品质将成为未来粮食气味物质研究领域的重要方向;同时,部分气味物质也被证实对粮仓中有害生物具有防控作用,将成为未来研发新型绿色储粮药剂的重要来源。 展开更多
关键词 粮食 气味物质 判别方法 代谢途径 安全储藏
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