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基于拆分残差网络的糖尿病视网膜病变分类 被引量:1
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作者 肖宇庭 吕晓琪 +1 位作者 谷宇 刘传强 《广西师范大学学报(自然科学版)》 CAS 北大核心 2024年第1期91-101,共11页
糖尿病视网膜病变是一种常见的糖尿病并发症。为提高糖尿病视网膜病变图像分级准确率,本文提出基于拆分残差网络的分级算法。通过融合归一化注意力,增强识别关键特征信息能力,使模型对病灶特征信息提取更具有针对性;利用全局上下文模块... 糖尿病视网膜病变是一种常见的糖尿病并发症。为提高糖尿病视网膜病变图像分级准确率,本文提出基于拆分残差网络的分级算法。通过融合归一化注意力,增强识别关键特征信息能力,使模型对病灶特征信息提取更具有针对性;利用全局上下文模块综合考虑不同尺度及网络层学习到的特征信息,进一步联系不同时期糖尿病视网膜病灶特点,增强模型表达能力;输出分类器设计多分支结构进行图像分级,提升多类别图像分级精度。实验结果得出模型准确率为94.86%,其他评价指标相比原主干网络模型均有提高。本文模型性能良好,实现了较高精度诊断分级糖尿病视网膜病变图像。 展开更多
关键词 医学图像处理 深度学习 糖尿病视网膜病变 注意力机制 残差网络
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基于残差拆分思想的中医“证”与临床指标关联关系再分析的数学模型的建立及应用 被引量:3
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作者 金锐 张冰 +2 位作者 刘森茂 薛春苗 赵茜 《中西医结合学报》 CAS 2011年第8期838-846,共9页
中医证实质研究是中医药基础理论研究的热点和难点,其中探讨中医证实质与生化指标关联关系的临床研究是重要方面之一。然而,由于各临床研究选取的生化指标与特定疾病关系密切,而传统的数据处理方法无法有效评价疾病因素的影响,故所得结... 中医证实质研究是中医药基础理论研究的热点和难点,其中探讨中医证实质与生化指标关联关系的临床研究是重要方面之一。然而,由于各临床研究选取的生化指标与特定疾病关系密切,而传统的数据处理方法无法有效评价疾病因素的影响,故所得结论会随着研究对象疾病类型的不同而变化,出现"同证异理"现象,并成为中医证实质研究的主要困惑之一。本研究基于信息学理论,从指标变化量的残差拆分入手,通过定量化计算中医的"证"概念于病理过程中提取的不同于"疾病"概念的新信息在指标变化上的表达,并结合其是否存在的显著性检验,建立一个能够客观分析影响临床指标变化的独立的证信息成分的大小及统计学意义的数学模型。将其应用于阳虚证环核苷酸研究文献数据分析的结果显示:第一,消除疾病因素后,对于环腺苷酸(cyclic adenosine monophosphate,cAMP),阳虚证信息成分量基本为负值,而对于环鸟苷酸(cyclic guanosine monophosphate,cGMP),阳虚证信息成分量基本为正值,在所有纳入文献中表现一致,提示阳虚证患者组出现较为明显的cAMP降低趋势和cGMP升高趋势,与国内相关研究结论相符;第二,对于cAMP和cGMP,所有纳入文献的阳虚证信息成分量与0值差异的统计学检验结果不尽一致,可能与原文献数据质量有关;第三,在某些情形下,疾病因素而非中医"证"因素可能是造成特定疾病阳虚证组与正常组相比有显著性差异的主要原因,在临床研究中应加以注意。本数学模型旨在为病证结合的中西医临床研究中疾病因素和"证"因素的处理提供数学工具,为中医证实质与临床指标关联关系研究提供新方法。 展开更多
关键词 数学模型 证实质 残差 阳虚证 环核苷酸
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应用残差总变分及低秩表示的视频去噪算法 被引量:2
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作者 张智勇 常侃 +2 位作者 陈诚 施静兰 覃团发 《信号处理》 CSCD 北大核心 2016年第5期558-566,共9页
为了有效地去除视频当中的高斯噪声和脉冲噪声,提出了一种新的视频去噪算法。该算法通过相似图像块组内的残差值总变分及低秩表示来同时探索图像块内的局部相似性以及图像块之间的相似性。首先,采用块匹配的方式在含噪视频中寻找最相似... 为了有效地去除视频当中的高斯噪声和脉冲噪声,提出了一种新的视频去噪算法。该算法通过相似图像块组内的残差值总变分及低秩表示来同时探索图像块内的局部相似性以及图像块之间的相似性。首先,采用块匹配的方式在含噪视频中寻找最相似图像块并组合成图像块组;其次将每个相似图像组表达为一个低秩矩阵及一个稀疏矩阵之和,并同时强调低秩矩阵内的残差总变分范数最小化;最后,通过求解最优化问题获得最终的低秩矩阵,即恢复出的图像块组数据。实验结果表明,本文的算法能够有效去除视频当中含有的高斯噪声和脉冲噪声。与同类算法相比,能够获得显著的峰值信噪比提升。 展开更多
关键词 视频去噪算法 残差总变范数 低秩表示 块匹配
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二值网络的分阶段残差二值化算法 被引量:2
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作者 任红萍 陈敏捷 +2 位作者 王子豪 杨春 殷绪成 《计算机系统应用》 2019年第1期38-46,共9页
二值网络在速度、能耗、内存占用等方面优势明显,但会对深度网络模型造成较大的精度损失.为了解决上述问题,本文提出了二值网络的"分阶段残差二值化"优化算法,以得到精度更好的二值神经网络模型.本文将随机量化的方法与XNOR-... 二值网络在速度、能耗、内存占用等方面优势明显,但会对深度网络模型造成较大的精度损失.为了解决上述问题,本文提出了二值网络的"分阶段残差二值化"优化算法,以得到精度更好的二值神经网络模型.本文将随机量化的方法与XNOR-net相结合,提出了两种改进算法"带有近似因子的随机权重二值化"和"确定权重二值化",以及一种全新的"分阶段残差二值化"的BNN训练优化算法,以得到接近全精度神经网络的识别准确率.实验表明,本文提出的"分阶段残差二值化"算法能够有效提升二值模型的训练精度,而且不会增加相关网络在测试过程中的计算量,从而保持了二值网络速度快、空间小、能耗低的优势. 展开更多
关键词 深度学习 二值网络 随机量化 高阶残差量化 阶段残差二值化
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改进Bayesian后验比的异常风速值检测方法 被引量:2
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作者 陈伟 吴布托 +1 位作者 裴喜平 王懿喆 《电网与清洁能源》 北大核心 2017年第2期104-111,116,共9页
风电场运行数据中含有异常风速值,为了优化风电数据的质量,提出了组合预测与Bayesian后验比的异常值检测方法。为了降低预测误差,先对风速序列建立Adaboost-BP网络和EMD-LV-SVM的组合预测模型,利用预测值与测量值的偏差得到含有粗大误... 风电场运行数据中含有异常风速值,为了优化风电数据的质量,提出了组合预测与Bayesian后验比的异常值检测方法。为了降低预测误差,先对风速序列建立Adaboost-BP网络和EMD-LV-SVM的组合预测模型,利用预测值与测量值的偏差得到含有粗大误差的残差序列;为了提高检测方法的可靠性,采用Bayesian后验比的检验方法识别残差序列中粗大误差,从而确定异常风速值的位置,并利用ARIMA方法修正异常风速值。RBF预测结果表明,所提方法能准确识别异常值,从而提高了风电场短期风速预测精度。 展开更多
关键词 异常风速值检测 组合预测模型 残差分 Bayesian后验比
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Super-resolution reconstruction for license plate images of moving vehicles
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作者 路小波 曾维理 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期457-460,共4页
A novel reconstruction method to improve the recognition of license plate texts of moving vehicles in real traffic videos is proposed, which fuses complimentary information among low resolution (LR) images to yield ... A novel reconstruction method to improve the recognition of license plate texts of moving vehicles in real traffic videos is proposed, which fuses complimentary information among low resolution (LR) images to yield a high resolution (HR) image. Based on the regularization super-resolution (SR) reconstruction schemes, this paper first introduces a residual gradient (RG) term as a new regularization term to improve the quality of the reconstructed image. Moreover, L1 norm is used to measure the residual data (RD) term and the RG term in order to improve the robustness of the proposed method. Finally, the steepest descent method is exploited to solve the energy functional. Simulated and real acquired video sequence experiments show the effectiveness and practicability of the proposed method and demonstrate its superiority over the bi-cubic interpolation and discontinuity adaptive Markov random field (DAMRF) SR method in both signal to noise ratios (SNR) and visual effects. 展开更多
关键词 SUPER-RESOLUTION residual gradient term residual data term license plate REGULARIZATION
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Shear creep characteristics and constitutive model of limestone 被引量:9
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作者 Yu Mei Mao Xianbiao Hu Xinyu 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第3期423-428,共6页
The characters of limestone in weak interlayer of a high rocky slope in Xuzhou, China, are studied by shear static test and shear creep test. The results show that limestone specimens have attenuation creep properties... The characters of limestone in weak interlayer of a high rocky slope in Xuzhou, China, are studied by shear static test and shear creep test. The results show that limestone specimens have attenuation creep properties and constant rate creep properties, almost have no accelerated creep properties. The exponential type empirical formula is selected to fit creep grading curves by polynomial regression analysis method, and the square sums of the fitting results residual are in the order of 10^(-7). Then grade creep curves at every shear loads are set up. Combining creep rate-time curve, the creep properties of limestone are analyzed. As the physical meaning of component model is clearer, the Poytin–Thomson model is set up. Through the least square method, the optimal parameters of Poytin–Thomson model are obtained,and the sums of squared residuals belong to 10^(-3)order of magnitude, which can meet the accuracy requirements of engineering calculation. So the Poytin–Thomson model can reflect the shear creep characteristics of limestone very well. 展开更多
关键词 Limestone Shear creep property Empirical formula Poytin–Thomson model
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Research on numerical welding experiment of a thick spherical shell structure
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作者 刘向东 姚熊亮 庞福振 《Journal of Marine Science and Application》 2008年第2期69-76,共8页
In this paper, in order to predict the residual deformation of thick spherical structure, a welding program is compiled in APDL language based on Ansys and a numerical welding experiment of a welding example is carrie... In this paper, in order to predict the residual deformation of thick spherical structure, a welding program is compiled in APDL language based on Ansys and a numerical welding experiment of a welding example is carried out. The temperature field of welding was simulated firstly, then a thermal-structure coupling analysis was carried out, and at last the residual stress and deformation after welding were got. After that, the numerical experiment result was compared with physical experiment one. The comparative analysis shows that the numerical simulation fits well with physical experiment. On the basis of that, a three-dimensional numerical experiment of a thick spherical shell structure was carried out to get the changing rule of stress and deformation of a thick spherical shell structure during welding. The research is of great value to the prediction of residual deformation and high precision machining. 展开更多
关键词 welding program thermal-structure coupling analysis residual stress residual deformation thick spherical shell structure
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Effect of asymmetric rolling on mechanical characteristics,texture and misorientations in ferritic steel
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作者 Wrofiski Sebastian Wierzbanowski Krzysztof +2 位作者 Bacroix Brigitte Chauveau Thierry Wrobel Mirostaw 《Journal of Central South University》 SCIE EI CAS 2013年第6期1443-1455,共13页
The mechanical and microstructural properties as well as crystallographic textures of asymmetrically rolled low carbon steel were studied.The modelling of plastic deformation was carried out in two scales:in the macro... The mechanical and microstructural properties as well as crystallographic textures of asymmetrically rolled low carbon steel were studied.The modelling of plastic deformation was carried out in two scales:in the macro-scale,using the finite elements method,and in the crystallographic scale,using the polycrystalline deformation model.The internal stress distribution in the rolling gap was calculated using the finite elements method and these stresses were then applied to the polycrystalline elasto-plastic deformation model.Selected mechanical properties,namely residual stress distribution,deformation work,applied force and torques,and bend amplitude,were calculated.The diffraction measurements,X-ray and electron backscatter diffraction,enabled the examination of texture heterogeneity and selected microstructure characteristics.The predicted textures agree well with those determined experimentally.The plastic anisotropy of cold rolled ferritic steel samples,connected with texture,was expressed by Lankford coefficient. 展开更多
关键词 asymmetric rolling crystallographic texture residual stress deformation model finite elements method DIFFRACTION
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Expression and Analysis of Microtus fortis against Schistosoma japonicum CD36 Gene
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作者 Yang Xiang Xue-Qin Zheng +6 位作者 Zhen Xiang Dong-Song Nie Yu Liu Xian-Lei Li Dian-Dian Lv Jun-Jian Hu Pei He 《Journal of Life Sciences》 2013年第8期791-795,共5页
The total RNA was extracted from Microtusfortis liver tissue which before being infected and after being infected 10 d and 15 d by the Schistosoma japonicum cercariae. Using Rattus norvegicus CD36 gene probe to hybrid... The total RNA was extracted from Microtusfortis liver tissue which before being infected and after being infected 10 d and 15 d by the Schistosoma japonicum cercariae. Using Rattus norvegicus CD36 gene probe to hybridize analysis of CD36 difference expression in the Microtus fortis liver tissues which were infected with Schistosorna japonicum before and after being infected. At the same time, the cDNA sequence and encoded amino acid sequence of the Rattus norvegicus CD36 gene and CD36 protein structural domains were analysized by using bioinformatics. The results showed that the CD36 expression levels in the liver tissue of Microtus fortis after being infected were significantly higher than before being infectied. The Rattus norvegicus CD36 cDNA sequence of a total length is 1625 bp and encoded 472 amino acid residues and Rattus norvegicus CD36 protein containing a CD36 superfamily domain. 展开更多
关键词 Microtusfortis Schistosomajaponicum CD36 EXPRESSION analysis.
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基于hp-VPINN的反应堆中子扩散计算方法研究
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作者 曾付林 张小龙 赵鹏程 《核动力工程》 EI CAS CSCD 北大核心 2024年第2期53-62,共10页
先进的反应堆模拟技术需要基于较少的实际探测数据反演全堆关键参数。针对这一需要,本文基于具有高阶多项式域分解功能的变分残差物理信息神经网络(hp-VPINN)构建计算模型,用于正向、反向求解中子扩散方程。该模型使用神经网络作为试函... 先进的反应堆模拟技术需要基于较少的实际探测数据反演全堆关键参数。针对这一需要,本文基于具有高阶多项式域分解功能的变分残差物理信息神经网络(hp-VPINN)构建计算模型,用于正向、反向求解中子扩散方程。该模型使用神经网络作为试函数,并将其代入中子扩散方程形成变分残差作为损失函数进行梯度下降。为了提高求解精度及效率,本文还根据中子扩散方程的物理特性提出了有效增殖系数智能搜索与反演等创新型关键技术,并基于鲸鱼优化算法(WOA)实现了神经网络超参数自优化。最后通过多个算例进行验证,结果表明该方法在具有较高精度的同时,实现了较低的训练数据依赖,为先进反应堆模拟技术提供了一条少量输入数据且较高精度输出的中子扩散求解途径。 展开更多
关键词 残差物理信息神经网络(hp-VPINN) 鲸鱼优化算法(WOA) 中子扩散方程 有效增殖系数 反应堆模拟技术
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RESIDUAL A POSTERIORI ERROR ESTIMATE OF A NEW TWO-LEVEL METHOD FOR STEADY NAVIER-STOKES EQUATIONS 被引量:2
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作者 Chunfeng REN Yichen MA 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2006年第4期478-490,共13页
Residual-based a posteriori error estimate for conforming finite element solutions of incompressible Navier-Stokes equations, which is computed with a new two-level method that is different from Volker John, is derive... Residual-based a posteriori error estimate for conforming finite element solutions of incompressible Navier-Stokes equations, which is computed with a new two-level method that is different from Volker John, is derived. A posteriori error estimate contains additional terms in comparison to the estimate for the solution obtained by the standard finite element method. The importance of the additional terms in the error estimates is investigated by studying their asymptotic behavior. For optimal scaled meshes, these bounds are not of higher order than the convergence of discrete solution. The two-level method aims to solve the nonlinear problem on a coarse grid with less computational work, then to solve the linear problem on a fine grid, which is superior to the usual finite element method solving a similar nonlinear problem on the fine grid. 展开更多
关键词 Finite element method Navier-Stokes equations residual-based a posteriori error estimate two-level method.
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LACK-OF-FIT TESTS BASED ON WEIGHTED RATIO OF RESIDUALS AND VARIANCES 被引量:1
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作者 Maozai TIAN Youxi LUO +2 位作者 Yunan SU Yan FAN Junlin HAN 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2012年第6期1202-1214,共13页
This article proposes a new lack-of-test based on the weighted ratio of residuals and variances for partially linear regression models. The large and small sampling properties of the proposed test are established. The... This article proposes a new lack-of-test based on the weighted ratio of residuals and variances for partially linear regression models. The large and small sampling properties of the proposed test are established. The testing procedure is illustrated via several examples. Simulation studies show that the testing procedures are powerful even in small samples. An application of the test to a real data set is presented. 展开更多
关键词 Empirical power Lack-of-fit test Monte Carlo quasi-residuals ratio of variances semi-parametric model.
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A new LS+AR model with additional error correction for polar motion forecast 被引量:8
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作者 YAO YiBin YUE ShunQiang CHEN Peng 《Science China Earth Sciences》 SCIE EI CAS 2013年第5期818-828,共11页
Polar motion depicts the slow changes in the locations of the poles due to the earth's internal instantaneous axis of rotation. The LS+AR model is recognized as one of the best models for polar motion prediction.T... Polar motion depicts the slow changes in the locations of the poles due to the earth's internal instantaneous axis of rotation. The LS+AR model is recognized as one of the best models for polar motion prediction.Through statistical analysis of the time series of the LS+AR model's short-term prediction residuals,we found that there is a good correlation of model prediction residuals between adjacent terms.These indicate that the preceding model prediction residuals and experiential adjustment matrixes can be used to correct the next prediction results,thereby forming a new LS+AR model with additional error correction that applies to polar motion prediction.Simulated predictions using this new model revealed that the proposed method can improve the accuracy and reliability of polar motion prediction.In fact,the accuracies of ultra short-term and short-term predictions using the new model were equal to the international best level at present. 展开更多
关键词 nolar motion forecast. LS+AR model correlation coefficient additional error correction
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How Does the General Output Quantity Distribution of Suppliers Affect the Value-appropriation of Supply Chain?
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作者 Yifei Du Shiming Li 《Journal of Systems Science and Information》 2006年第1期149-157,共9页
This paper studies the problem of value-appropriation of supply chain, which is composed of a monopoly manufacturer downstream and multiple suppliers upstream. Firstly, we introduce two special examples in which outpu... This paper studies the problem of value-appropriation of supply chain, which is composed of a monopoly manufacturer downstream and multiple suppliers upstream. Firstly, we introduce two special examples in which output distribution of suppliers satisfy equal or equal-difference sequence. It is found that the more difference the distribution will be, the less preference will be gain by the manufacturer in the value-appropriation of supply chain. For the general distribution, the parameter "competitive residual" is introduced to score the influence of the suppliers' output quantity distribution on manufacturer's preference. The general conclusion will be given and it can directly deduce the conclusions above. Finally, we extend our basic conclusion to the more general situation in which the numbers of suppliers are not equal. 展开更多
关键词 hybrid game core output quantity distribution competitive residual
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