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如何利用奇部和偶部判定级数的敛散性 被引量:1
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作者 朱佑彬 柴华岳 李小斌 《高等数学研究》 2018年第3期10-11,共2页
本文介绍一种利用奇部和偶部判定级数敛散性的方法,利用它可以快速判定某些级数的敛散性.
关键词 奇部 敛散性
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试论常用眼部奇穴与十四经脉的关系 被引量:4
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作者 戚其华 金明卜 《针灸临床杂志》 2001年第9期1-3,共3页
关键词 经络 十四经脉
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改进的live-wire交互式胸片图像分割 被引量:1
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作者 张微 陈树越 李全栋 《应用光学》 CAS CSCD 北大核心 2010年第4期593-596,共4页
肺部轮廓提取是计算机辅助诊断(computer-aided detection,CAD)的关键之一,并且能为医生提供可靠的诊断数据。提出了一种交互式肺部分割方法,用优化的Gabor奇滤波器对胸片图像进行滤波得到边缘响应能量图,然后用此边缘响应能量值来构造L... 肺部轮廓提取是计算机辅助诊断(computer-aided detection,CAD)的关键之一,并且能为医生提供可靠的诊断数据。提出了一种交互式肺部分割方法,用优化的Gabor奇滤波器对胸片图像进行滤波得到边缘响应能量图,然后用此边缘响应能量值来构造Live-wire代价函数进行肺部分割。实验表明该算法能正确区分强弱边缘,快速有效地提取出肺部轮廓,与传统算法相比,能减少人机交互次数,更具鲁棒性和效率性的优点。 展开更多
关键词 医学图像分割 胸片图像 live-wire算法 Gabor奇部滤波器
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基于Gabor滤波器的图像边缘检测算法
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作者 高晓兴 曹丽 常桂然 《计算机应用》 CSCD 北大核心 2008年第10期2625-2627,共3页
采用Canny算子进行边缘检测时,需人工设定高低2个阈值。对不同的图像采用相同的阈值,边缘检测效果差异很大,这一点限制了Canny算子在实际中的应用。针对这一问题,提出了一种基于Gabor奇部滤波器的边缘检测方法,在不同的尺度下分别采用... 采用Canny算子进行边缘检测时,需人工设定高低2个阈值。对不同的图像采用相同的阈值,边缘检测效果差异很大,这一点限制了Canny算子在实际中的应用。针对这一问题,提出了一种基于Gabor奇部滤波器的边缘检测方法,在不同的尺度下分别采用非极大值抑制,然后利用Canny算子在高低阈值图像中查找边缘点的方法对图像进行边缘检测,无需人为地设定任何参数。实验结果表明这种算法不但克服了Canny算法中人为设定阈值的缺陷,而且能有效去除图像中的伪边缘。 展开更多
关键词 边缘检测 Gabor奇部滤波器 CANNY算子
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有限维模李超代数M的限制性
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作者 李强 马丽丽 韩旸 《辽宁工程技术大学学报(自然科学版)》 CAS 北大核心 2015年第1期141-144,共4页
为研究模李超代数M的限制性问题,把模李超代数分解成奇部成分和偶部成分.结合限制李超代数的等价定义,分别讨论了模李超代数的偶部和奇部元素的性质.利用限制李超代数的p-理想,研究了p-映射的存在性.构造p-映射,将p-映射作用在模李超代... 为研究模李超代数M的限制性问题,把模李超代数分解成奇部成分和偶部成分.结合限制李超代数的等价定义,分别讨论了模李超代数的偶部和奇部元素的性质.利用限制李超代数的p-理想,研究了p-映射的存在性.构造p-映射,将p-映射作用在模李超代数的偶部元素上,确定存在p-半线性映射与之相关.研究结果表明:给出了模李超代数M是限制李超代数的充分必要条件,得到p-映射与p-半线性映射之间的关系. 展开更多
关键词 模李超代数 限制性 奇部 P-映射 p-半线性映射
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一种基于Gabor滤波器的超声图像边缘检测方法 被引量:2
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作者 李志明 冯成德 张慧 《中国测试技术》 2006年第6期75-77,共3页
针对检测超声图像的边缘问题,介绍了一种基于Gabor奇部滤波器进行边缘检测的综合方法。为了去除图像噪声,首先进行基于小波变换和中值滤波的降噪处理,然后利用高斯函数平滑图像。在边缘检测过程中,使用Gabor奇部滤波器检测边缘。最后,... 针对检测超声图像的边缘问题,介绍了一种基于Gabor奇部滤波器进行边缘检测的综合方法。为了去除图像噪声,首先进行基于小波变换和中值滤波的降噪处理,然后利用高斯函数平滑图像。在边缘检测过程中,使用Gabor奇部滤波器检测边缘。最后,使用非最大值抑制得到最终结果。结果表明该方法是对超声图像进行边缘检测的一种有用方法。当然,该方法也具有普遍性,可以应用到其他图像。 展开更多
关键词 超声图像 小波去噪 边缘检测 Gabor奇部滤波器
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基于Gabor小波的人脸边缘检测算法研究
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作者 曹丽 《中小企业管理与科技》 2012年第15期282-283,共2页
本文提出了一种基于Gabor奇部滤波器的边缘检测方法,在不同的尺度下分别采用非极大值抑制,然后利用Canny算子在高低阈值图像中查找边缘点的方法对图像进行边缘检测,无需人为的设定任何参数。实验结果表明这种算法不但克服了Canny算法中... 本文提出了一种基于Gabor奇部滤波器的边缘检测方法,在不同的尺度下分别采用非极大值抑制,然后利用Canny算子在高低阈值图像中查找边缘点的方法对图像进行边缘检测,无需人为的设定任何参数。实验结果表明这种算法不但克服了Canny算法中人为设定阈值的缺陷,而且有效地去除了图像中的伪边缘。 展开更多
关键词 边缘检测 Gabor奇部滤波器 CANNY算子
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试论卡洛尔·欧茨《奇境》四部曲的对话性
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作者 宋瑞南 《作家》 北大核心 2012年第24期29-30,共2页
卡洛尔·欧茨是美国当代文学著名女作家,本文通过分析其《奇境》四部曲人物之间的对话关系、人物与自我的对话、作者与其设置的主人公之间的关系探讨其对话艺术。
关键词 境》四 对话性 卡洛尔·欧茨
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Local Bifurcation of a Thin Rectangle Plate with the Friction Support Boundary
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作者 叶敏 张伟亿 《Transactions of Tianjin University》 EI CAS 2002年第2期114-118,共5页
The dynamical equations of a thin rectangle plate subjected to the friction support boundary and its plane force are established in this paper. The local bifurcation of this system is investigated by using L S method... The dynamical equations of a thin rectangle plate subjected to the friction support boundary and its plane force are established in this paper. The local bifurcation of this system is investigated by using L S method and the singularity theory. The Z 2 bifurcation in non degenerate case is discussed. The local bifurcation diagrams of the unfolding parameters and the bifurcation response characters referred to the physical parameters of the system are obtained by numerical simulation. The results of the computer simulation are coincident with the theoretical analysis and experimental results. 展开更多
关键词 thin rectangle plate L S method singularity theory local bifurcation numerical simulation
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Detection of P2P botnet based on network behavior features and Dezert-Smarandache theory 被引量:1
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作者 Song Yuanzhang Chen Yuan +2 位作者 Wang Junjie Wang Anbang Li Hongyu 《Journal of Southeast University(English Edition)》 EI CAS 2018年第2期191-198,共8页
In order to improve the accuracy of detecting the new P2P(peer-to-peer)botnet,a novel P2P botnet detection method based on the network behavior features and Dezert-Smarandache theory is proposed.It focuses on the netw... In order to improve the accuracy of detecting the new P2P(peer-to-peer)botnet,a novel P2P botnet detection method based on the network behavior features and Dezert-Smarandache theory is proposed.It focuses on the network behavior features,which are the essential abnormal features of the P2P botnet and do not change with the network topology,the network protocol or the network attack type launched by the P2P botnet.First,the network behavior features are accurately described by the local singularity and the information entropy theory.Then,two detection results are acquired by using the Kalman filter to detect the anomalies of the above two features.Finally,the above two detection results are fused with the Dezert-Smarandache theory to obtain the final detection results.The experimental results demonstrate that the proposed method can effectively detect the new P2P botnet and that it considerably outperforms other methods at a lower degree of false negative rate and false positive rate,and the false negative rate and the false positive rate can reach 0.09 and 0.12,respectively. 展开更多
关键词 P2P(peer-to-peer)botnet local singularity ENTROPY Kalman filter Dezert-Smarandache theory
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INTERPOLATION OF HEAD-RELATED TRANSFER FUNCTIONS USING SPHERICAL FOURIER EXPANSION 被引量:1
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作者 Huang Qinghua Fang Yong 《Journal of Electronics(China)》 2009年第4期571-576,共6页
A new interpolation algorithm for Head-Related Transfer Function (HRTF) is proposed to realize 3D sound reproduction via headphones in arbitrary spatial direction. HRTFs are modeled as a weighted sum of spherical ha... A new interpolation algorithm for Head-Related Transfer Function (HRTF) is proposed to realize 3D sound reproduction via headphones in arbitrary spatial direction. HRTFs are modeled as a weighted sum of spherical harmonics on a spherical surface. Truncated Singular Value Decomposition (SVD) is adopted to calculate the weights of the model. The truncation number is chosen according to Frobenius norm ratio and the partial condition number. Compared with other interpolated methods, our proposed approach not only is continuous but exploits global information of available directions. The HRTF from any desired direction can be and interpolated results demonstrate that our obtained more accurately and robustly. Reconstructed proposed algorithm acquired better performance. 展开更多
关键词 Head-Related Transfer Function (HRTF) INTERPOLATION Spherical Fourier Expansion (SFE) Truncated Singular Value Decomposition (SVD) Partial condition number
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A Generalized Form of Whitney's Theorem
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作者 CEN Yan-ming CEN Li-hui 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期75-78,共4页
Whitney's theorem is a famous theorem in the local singularity theory. In this paper, as an application of Malgrange preparation theorem, a generalized form of Whitney's theorem will be derived.
关键词 generalized of Whitney's theorem
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On the Diophantine Equation y^2= px(x^2+ 2)
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作者 WANG Xiao-ying 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期499-503,共5页
For any fixed odd prime p, let N(p) denote the number of positive integer solutions (x, y) of the equation y^2 = px(x^2 + 2). In this paper, using some properties of binary quartic Diophantine equations, we pro... For any fixed odd prime p, let N(p) denote the number of positive integer solutions (x, y) of the equation y^2 = px(x^2 + 2). In this paper, using some properties of binary quartic Diophantine equations, we prove that ifp ≡ 5 or 7(mod 8), then N(p) = 0; ifp ≡ 1(mod 8), then N(p) 〈 1; if p〉 3 andp ≡ 3(rood 8), then N(p) ≤ 2. 展开更多
关键词 cubic and quartic Diophantine equation number of solutions upper bound 2000 MR Subject Classification: 11D25
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Calculation method of the signal-to-noise ratio attribute of seismic data based on structural orientation
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作者 Zhao Yan Mao Ning-Bo Chen Xu 《Applied Geophysics》 SCIE CSCD 2019年第4期455-462,560,共9页
At present,most signal-to-noise ratio(SNR)estimation methods can only calculate the global and not the local SNR of seismic data.This paper proposes a calculation method of a structure-oriented-based seismic SNR attri... At present,most signal-to-noise ratio(SNR)estimation methods can only calculate the global and not the local SNR of seismic data.This paper proposes a calculation method of a structure-oriented-based seismic SNR attribute.The purpose is to characterize the temporal and spatial variation of the seismic data SNR.First,the local slope parameters of the seismic events are calculated using a plane wave decomposition filter.Then,the singular value decomposition method is used to calculate the local seismic data SNR,thereby obtaining it in time and space.The proposed method overcomes the insufficiency of a conventional global SNR to characterize any local seismic data features and uses the SNR as an attribute of seismic data to more accurately describe the signal-noise energy distribution characteristics of seismic data in time and space.The results of a theoretical model test and real data processing show that the SNR attribute can be used not only for seismic data quality evaluation but also for analysis and evaluation of denoising methods. 展开更多
关键词 Seismic data signal-to-noise ratio attribute local slope singular value decomposition structure-oriented
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E-characteristic Polynomials of Real Rectangular Tensor
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作者 吴伟 陈肖肖 《Transactions of Tianjin University》 EI CAS 2014年第3期232-235,共4页
By the resultant theory, the E-characteristic polynomial of a real rectangular tensor is defined. It is proved that an E-singular value of a real rectangular tensor is always a root of the E-characteristic polynomial.... By the resultant theory, the E-characteristic polynomial of a real rectangular tensor is defined. It is proved that an E-singular value of a real rectangular tensor is always a root of the E-characteristic polynomial. The definition of the regularity of square tensors is generalized to the rectangular tensors, and in the regular case, a root of the Echaracteristic polynomial of a special rectangular tensor is an E-singular value of the rectangular tensor. Moreover, the best rank-one approximation of a real partially symmetric rectangular tensor is investigated. 展开更多
关键词 E-characteristic polynomial rectangular tensor E-singular value rank-one approximation
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On Pairwise Singular Sets and Pairwise Singular Maps
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作者 Rina Pankaj Verma Mamta Singh 《Journal of Mathematics and System Science》 2014年第4期261-268,共8页
In this paper we introduce the concept of pairwise singular sets and pairwise singular maps between pairwise locally compact and pairwise hausdorff spaces and study the properties of pairwise singular maps.
关键词 Pairwise singular sets pairwise singular maps
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Practical Polar Code Construction For Degraded Multiple-Relay Networks 被引量:2
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作者 Bin Duo Xiaoling Zhong Yong Guo 《China Communications》 SCIE CSCD 2017年第4期127-139,共13页
In this paper, based on the characteristics of polar codes, a new decode-and-forward strategy called generalized partial information relaying protocol is proposed for degraded multiple-relay networks with orthogonal r... In this paper, based on the characteristics of polar codes, a new decode-and-forward strategy called generalized partial information relaying protocol is proposed for degraded multiple-relay networks with orthogonal receiver components(MRNORCs). In such a protocol, with the help of partial information from previous nodes, each relay node tries to recover the received source message and re-encodes part of the decoded message for transmission to satisfy the decoding requirements for the following relay node or the destination node. In order to construct practical polar codes, the nested structures are developed based on this protocol and the information sets corresponding to the partial messages forwarded are also calculated. The proposed scheme is proved to be capable of achieving the theoretical capacity of the degraded MRN-ORCs while still retains the low-complexity feature of polar codes. We perform simulations to testify the practicability of the proposed scheme and compare polar codes by using successive-cancellation list decoder(SCLD) with traditional low-density parity-check(LDPC) codes. The results show that the obtained polar codes provide significant gain. 展开更多
关键词 cooperative communication multiple-relay networks channel capacity decode-and-forward polar codes
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On Relative Stability in 4-Dimensional Duck Solution 被引量:1
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作者 Kiyoyuki Tchizawa 《Journal of Mathematics and System Science》 2012年第9期558-563,共6页
This paper gives the existence of a relatively stable duck solution in a slow-fast system in R2+2 with an invariant manifold. The slow-fast system in R2+: has a 2-dimensional slow vector field and a 2-dimensional f... This paper gives the existence of a relatively stable duck solution in a slow-fast system in R2+2 with an invariant manifold. The slow-fast system in R2+: has a 2-dimensional slow vector field and a 2-dimensional fast vector field. The fast vector field restricts a feasible region of the slow vector field strictly. In the case of the slow-fast system in R2+1 , that is, the fast vector field is l-dimension, it is classified according to its sign, because it gives only negative(-), positive(+) or zero sign. Then it is attractive, repulsive or stationary. On the other hand, in R2~2 , the fast vector field has combinatorial cases. It causes a complex state to analyze the system. First, we introduce a local model near the pseudo singular point on which we classify the fast vector field attractive(-,-), attractive-repulsive(-,+) or repulsive(+,+), simply as possible. We prove the existence of a 4-dimensional duck solution in the local model. Secondarily, we assume that the slow-fast system has an invariant manifold near the pseudo singular point. When the invariant manifold has a homoclinic point near the pseudo singular point, we show that the slow-fast sytem has a 4-dimensional duck solution having a relatively stable region. 展开更多
关键词 Slow-fast system singular perturbation BIFURCATION nonstandard analysis.
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The Nonlocal Singularly Perturbed Problems forNonlinear Hyperbolic Differential Equation
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作者 莫嘉琪 宋乾坤 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2002年第2期159-166,共8页
A class of nonlocal singnlarly perturbed problems for the hyperbolic dif-ferential equation are considered. Under snitable conditions, we discuss the asymptoticbehavior of solution for the initial boundary value probl... A class of nonlocal singnlarly perturbed problems for the hyperbolic dif-ferential equation are considered. Under snitable conditions, we discuss the asymptoticbehavior of solution for the initial boundary value problems. 展开更多
关键词 nonlocal problem singnlar perturbation nonlinear hyperbolic differential equation.
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Mechanism of action of two insect toxins huwentoxin-Ⅲ and hainantoxin-Ⅵ on voltage-gated sodium channels 被引量:1
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作者 Rui-lan WANG Su YI Song-ping LIANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2010年第6期451-457,共7页
Selenocosmia huwena and Selenocosmia hainana are two tarantula species found in southern China.Their venoms contain abundant peptide toxins.Two new neurotoxic peptides,huwentoxin-Ⅲ(HWTX-Ⅲ) and hainantoxin-VI(HNTX-VI... Selenocosmia huwena and Selenocosmia hainana are two tarantula species found in southern China.Their venoms contain abundant peptide toxins.Two new neurotoxic peptides,huwentoxin-Ⅲ(HWTX-Ⅲ) and hainantoxin-VI(HNTX-VI),were obtained from the venom using ion-exchange chromatography and reverse-phase high performance liquid chromatography(RP-HPLC).The mechanism of action of HWTX-Ⅲ and HNTX-VI on insect neuronal voltage-gated sodium channels(VGSCs) was studied via whole-cell patch clamp techniques.In a fashion similar to δ-atracotoxins,HNTX-VI can induce a slowdown of current inactivation of the VGSC and reduction in the peak of Na+ current in cockroach dorsal unpaired median(DUM) neurons.Meanwhile,10 μmol/L HNTX-IV caused a positive shift of steady-state inactivation of sodium channel.HWTX-ⅡI inhibited VGSCs on DUM neurons(concentration of toxin at half-maximal inhibition(IC50)≈1.106 μmol/L) in a way much similar to tetrodotoxin(TTX).HWTX-Ⅲ had no effect on the kinetics of activation and inactivation.The shift in the steady-state inactivation curve was distinct from other depressant spider toxins.The diverse effect and the mechanism of action of the two insect toxins illustrate the diverse biological activities of spider toxins and provide a fresh theoretical foundation to design and develop novel insecticides. 展开更多
关键词 Insect neurotoxin Dorsal unpaired median neurons Sodium channel Whole-cell patch clamp technique
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