期刊文献+
共找到1,637篇文章
< 1 2 82 >
每页显示 20 50 100
Dual-Path Vision Transformer用于急性缺血性脑卒中辅助诊断
1
作者 张桃红 郭学强 +4 位作者 郑瀚 罗继昌 王韬 焦力群 唐安莹 《电子科技大学学报》 EI CAS CSCD 北大核心 2024年第2期307-314,共8页
急性缺血性脑卒中是由于脑组织血液供应障碍导致的脑功能障碍,数字减影脑血管造影(DSA)是诊断脑血管疾病的金标准。基于患者的正面和侧面DSA图像,对急性缺血性脑卒中的治疗效果进行分级评估,构建基于Vision Transformer的双路径图像分... 急性缺血性脑卒中是由于脑组织血液供应障碍导致的脑功能障碍,数字减影脑血管造影(DSA)是诊断脑血管疾病的金标准。基于患者的正面和侧面DSA图像,对急性缺血性脑卒中的治疗效果进行分级评估,构建基于Vision Transformer的双路径图像分类智能模型DPVF。为了提高辅助诊断速度,基于EdgeViT的轻量化设计思想进行了模型的构建;为了使模型保持轻量化的同时具有较高的精度,提出空间-通道自注意力模块,促进Transformer模型捕获更全面的特征信息,提高模型的表达能力;此外,对于DPVF的两分支的特征融合,构建交叉注意力模块对两分支输出进行交叉融合,促使模型提取更丰富的特征,从而提高模型表现。实验结果显示DPVF在测试集上的准确率达98.5%,满足实际需求。 展开更多
关键词 急性缺血性脑卒中 视觉Transformer 双分支网络 特征融合
下载PDF
Mechanical properties of fine-grained dual phase low-carbon steels based on dynamic transformation 被引量:1
2
作者 Haiwei Xu Wangyue Yang Zuqing Sun 《Journal of University of Science and Technology Beijing》 CSCD 2008年第5期556-560,共5页
The fine grained dual phase (FG-DP) steel with ferrite grains of 2-4.5 μm and martensite islands smaller than 3 μm was obtained through the mechanism of deformation-enhanced ferrite transformation (DEFT). Mechan... The fine grained dual phase (FG-DP) steel with ferrite grains of 2-4.5 μm and martensite islands smaller than 3 μm was obtained through the mechanism of deformation-enhanced ferrite transformation (DEFT). Mechanical properties of the steel were tested at room temperature. The results indicated that with a similar volume fraction of martensite (about 20vol%),FG-DP steel exhibited a superior combination of higher strength and more rapid strain hardening at low strains compared with the coarse-grained dual phase (CG-DP) steel obtained by critical annealing. The combination of higher strength,large elongation,and more rapid strain hardening of FG-DP steel can be attributed to the fine ferrite grain and finely dispersed martensite islands. In addition,the uniformly distributed martensite islands in FG-DP steel have smaller interspacing compared with that of CG-DP steel. So,at the initial plastic deformation stage,the plastic deformation of ferrite was restrained and more pronounced load was transferred from ferrite to martensite. The plastic deformation of martensite in FG-DP steel started earlier. 展开更多
关键词 deformation-enhanced transformation dual phase steel microstructure refinement mechanical behavior
下载PDF
DUAL NUMBER TRANSFORMATION AND ITS APPLICATION TO ROBOT WITH REDUNDANCY
3
作者 Wang huian(Department of Automatic Control .NUAA 29 Yudao Street,Nanjing 210016 ,P.R.China) 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1994年第1期92-101,共10页
This paper presents the application of dual-number matrix to the formulation of Jacobian equations of robot with redundancy, the analytical technique that is based on the dual-number matrices, a 3 × 3 matrix with... This paper presents the application of dual-number matrix to the formulation of Jacobian equations of robot with redundancy, the analytical technique that is based on the dual-number matrices, a 3 × 3 matrix with dualnumber elements, and the dual-number transformation method. Dual-number matrices make possible a concise representation of joint parameters. In particular, the method can effectively be used for direct determination of Jacobian matrices. It is shown that the proposed procedure contributes a simplified approach to the formulation of robotic kinematics, dynamics and control system modelling. 展开更多
关键词 MODELLING dual NUMBER transformation ROBOT with REDUNDANCY robottes dynamics
下载PDF
The Dual Functionals for the Generalized Ball Basis of Wang-Said Type and Basis Transformation Formulas 被引量:2
4
作者 Ping Jiang Hongyi Wu Jieqing Tan 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2006年第3期248-256,共9页
The generalized Ball curves of Wang-Said type with a position parameter L not only unify the Wang-Ball curves and the Said-Ball curves, but also include several useful intermediate curves. This paper presents the dual... The generalized Ball curves of Wang-Said type with a position parameter L not only unify the Wang-Ball curves and the Said-Ball curves, but also include several useful intermediate curves. This paper presents the dual functionals for the generalized Ball basis of Wang-Said type. The relevant basis transformation formulae are also worked out. 展开更多
关键词 双功能 基本变形 算法 Wang-Said型 伯恩斯坦原理
下载PDF
Green Transformation of Chinese Oil and Gas Enterprises in Context of the “Dual Carbon” Goals
5
作者 Wu Mouyuan Kang Yu +2 位作者 Fan Xuqiang Li Chunshuo Lan Mengtong 《China Oil & Gas》 CAS 2022年第3期9-14,共6页
2021 was the first year of the“14th Five-year Plan”and the year in which the“30·60 Goals”were officially implemented.In the first year of the“Dual Carbon Goals”,domestic oil and gas enterprises vigorously e... 2021 was the first year of the“14th Five-year Plan”and the year in which the“30·60 Goals”were officially implemented.In the first year of the“Dual Carbon Goals”,domestic oil and gas enterprises vigorously expanded their new energy businesses while actively developing their main businesses,bravely shouldered their responsibility for supply guarantee and comprehensively accelerated their green transformation,creating typical experience and practices. 展开更多
关键词 dual transformation ENTERPRISES
下载PDF
CHARACTERISTICS OF MARTENSITIC TRANSFORMATION IN DUAL-PHASE STEELS
6
作者 SHEN Xianpu ZHANG Jie WU Baorong Central Iron and Steel Research Institute.Ministry of Metallurgical Industry.Beijing,ChinaLEI Tingquan Harbin Institute of Technology,Harbin.China Dept.No.13,Central Iron and Steel Research Institute,Ministry of Metallurgical Industry,Beijing,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1989年第5期333-336,共4页
A theorectical expression for the driving force and M_(?) point of martensitic transformation has been proposed.The M_(?) values using this expression are in good agreement with that obtained experimentally.It was fou... A theorectical expression for the driving force and M_(?) point of martensitic transformation has been proposed.The M_(?) values using this expression are in good agreement with that obtained experimentally.It was found that the values of M_(?) and M_(?) are not only related to the carbon content in martensite,but also to the volume fraction of ferrite. 展开更多
关键词 dual-phase steel phase transformation martenstie M_s M_f
下载PDF
Megacity pathways in China under the dual carbon goal:The case of Shanghai
7
作者 Weiduo Zhou Fengqi Zhou Guiyang Zhuang 《Chinese Journal of Population,Resources and Environment》 2024年第3期241-249,共9页
The pathways to achieving carbon neutrality at the city level are diverse due to varying energy supply and demand conditions.Shanghai faces obstacles such as limited land resources,high costs of renewable energy techn... The pathways to achieving carbon neutrality at the city level are diverse due to varying energy supply and demand conditions.Shanghai faces obstacles such as limited land resources,high costs of renewable energy technologies,and instability of renewable energy.These challenges hinder the city’s efforts to achieve carbon peak and carbon neutrality(dual carbon).Therefore,Shanghai must identify and optimize its development path for renewable energy under the dual carbon goal.We employed the Low Emissions Analysis Platform Shanghai(LEAP-SH)model to simulate the impact of policies,such as industrial upgrading,energy efficiency improvement,energy structure optimization,increased technical innovation on energy,and ecological restoration,on the carbon emission pathways from 2022 to 2060 using five different scenarios.Our results indicate that Shanghai has the potential to achieve carbon neutrality in 2059 by promoting carbon reduction,pollution control,and green expansion.Moreover,we determined that the manufacturing industry;power generation industry;and transportation,storage,and mail services are the three major sectors for emission reduction under the dual carbon goal.Furthermore,the capacity and output of coal-fired power plants will be gradually replaced by offshore wind power in the dual carbon pathway.Finally,this study proposes countermeasures and suggestions for Shanghai to attain the dual carbon goal and high-quality development. 展开更多
关键词 dual carbon goal Pathway Energy transformation Mega city SHANGHAI
下载PDF
DCFNet:An Effective Dual-Branch Cross-Attention Fusion Network for Medical Image Segmentation
8
作者 Chengzhang Zhu Renmao Zhang +5 位作者 Yalong Xiao Beiji Zou Xian Chai Zhangzheng Yang Rong Hu Xuanchu Duan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期1103-1128,共26页
Automatic segmentation of medical images provides a reliable scientific basis for disease diagnosis and analysis.Notably,most existing methods that combine the strengths of convolutional neural networks(CNNs)and Trans... Automatic segmentation of medical images provides a reliable scientific basis for disease diagnosis and analysis.Notably,most existing methods that combine the strengths of convolutional neural networks(CNNs)and Transformers have made significant progress.However,there are some limitations in the current integration of CNN and Transformer technology in two key aspects.Firstly,most methods either overlook or fail to fully incorporate the complementary nature between local and global features.Secondly,the significance of integrating the multiscale encoder features from the dual-branch network to enhance the decoding features is often disregarded in methods that combine CNN and Transformer.To address this issue,we present a groundbreaking dual-branch cross-attention fusion network(DCFNet),which efficiently combines the power of Swin Transformer and CNN to generate complementary global and local features.We then designed the Feature Cross-Fusion(FCF)module to efficiently fuse local and global features.In the FCF,the utilization of the Channel-wise Cross-fusion Transformer(CCT)serves the purpose of aggregatingmulti-scale features,and the Feature FusionModule(FFM)is employed to effectively aggregate dual-branch prominent feature regions from the spatial perspective.Furthermore,within the decoding phase of the dual-branch network,our proposed Channel Attention Block(CAB)aims to emphasize the significance of the channel features between the up-sampled features and the features generated by the FCFmodule to enhance the details of the decoding.Experimental results demonstrate that DCFNet exhibits enhanced accuracy in segmentation performance.Compared to other state-of-the-art(SOTA)methods,our segmentation framework exhibits a superior level of competitiveness.DCFNet’s accurate segmentation of medical images can greatly assist medical professionals in making crucial diagnoses of lesion areas in advance. 展开更多
关键词 Convolutional neural networks Swin Transformer dual branch medical image segmentation feature cross fusion
下载PDF
基于双流特征融合的肺结节图像分割网络
9
作者 郝胜男 庞建华 《现代电子技术》 北大核心 2025年第1期1-7,共7页
为了提高对肺结节的准确分割,文中提出一种CSF-UNet的双骨干网络特征提取方法。使用两种不同侧重的骨干网络并行提取图像特征,通过利用ConvNeXt网络提取局部特征,并结合Swin Transformer网络提取全局特征来提升模型的特征提取能力。提... 为了提高对肺结节的准确分割,文中提出一种CSF-UNet的双骨干网络特征提取方法。使用两种不同侧重的骨干网络并行提取图像特征,通过利用ConvNeXt网络提取局部特征,并结合Swin Transformer网络提取全局特征来提升模型的特征提取能力。提出了一种自适应大核融合模块,有效地融合两种不同规格的特征,通过串联两个大核卷积获得更大的感受野和动态选择机制来突出重要的空间区域。在SPPF中融合了ECA通道注意力和密集链接,提出了ESPP模块以进一步挖掘双骨干网络提取的高级语义信息,使网络更加关注重要的特征通道。在LIDC数据集上的实验结果表明,提出的模型在3个指标上优于基本UNet模型以及最近几年其他研究团队提出的针对该数据集的分割网络。最终,CSF-UNet模型实现了78.1%的IoU、87.71%的DSC、87.19%的敏感度和88.23%的精确度。这些结果表明,该模型在肺结节分割方面表现出良好的性能,对医生进行早期肺结节诊断具有重要的临床意义和应用价值。 展开更多
关键词 肺结节 TRANSFORMER ConvNeXt 注意力机制 计算机视觉 双骨干网络
下载PDF
结合视觉显著性与Dual-PCNN的红外与可见光图像融合 被引量:8
10
作者 侯瑞超 周冬明 +2 位作者 聂仁灿 刘栋 郭晓鹏 《计算机科学》 CSCD 北大核心 2018年第B06期162-166,共5页
针对现存的红外与可见光图像融合算法亮度不均、目标不突出、对比度不高、细节丢失等问题,结合非下采样剪切波变换(NSST)具有多尺度、最具稀疏表达的特性,显著性检测具有突出红外目标的优势,双通道脉冲耦合神经网络(Dual-PCNN)具有耦合... 针对现存的红外与可见光图像融合算法亮度不均、目标不突出、对比度不高、细节丢失等问题,结合非下采样剪切波变换(NSST)具有多尺度、最具稀疏表达的特性,显著性检测具有突出红外目标的优势,双通道脉冲耦合神经网络(Dual-PCNN)具有耦合、脉冲同步激发等优点,提出一种基于NSST结合视觉显著性引导Dual-PCNN的图像融合方法。首先,通过NSST分解红外与可见光图像各方向的高频与低频子带系数;然后,低频子带系数采用基于显著性决策图引导Dual-PCNN融合策略,高频子带系数采用改进的空间频率作为优化Dual-PCNN的激励进行融合;最后,经过NSST逆变换得到融合图像。实验结果表明,融合图像红外目标突出且可见光背景细节丰富。该方法相比于其他融合算法在主观评价与客观评价上都有一定程度的改善。 展开更多
关键词 非下采样剪切波变换 视觉显著性 双通道脉冲耦合神经网络 图像融合
下载PDF
Adaptive Dual-Threshold Edge Detection Based on Wavelet Transform 被引量:3
11
作者 侯舒娟 梅文博 张志明 《Journal of Beijing Institute of Technology》 EI CAS 2003年第3期247-250,共4页
In order to solve the problems of local maximum modulus extraction and threshold selection in the edge detection of finite resolution digital images, a new wavelet transform based adaptive dual threshold edge detec... In order to solve the problems of local maximum modulus extraction and threshold selection in the edge detection of finite resolution digital images, a new wavelet transform based adaptive dual threshold edge detection algorithm is proposed. The local maximum modulus is extracted by linear interpolation in wavelet domain. With the analysis on histogram, the image is filtered with an adaptive dual threshold method, which effectively detects the contours of small structures as well as the boundaries of large objects. A wavelet domain's propagation function is used to further select weak edges. Experimental results have shown the self adaptivity of the threshold to images having the same kind of histogram, and the efficiency even in noise tampered images. 展开更多
关键词 wavelet transform edge detection propagation function dual threshold
下载PDF
Quantization-Based Robust Image Watermarking Using the Dual Tree Complex Wavelet Transform 被引量:4
12
作者 LIU Jinhua SHE Kun 《China Communications》 SCIE CSCD 2010年第4期1-6,共6页
Conventional quantization index modulation (QIM) watermarking uses the fixed quantization step size for the host signal.This scheme is not robust against geometric distortions and may lead to poor fidelity in some are... Conventional quantization index modulation (QIM) watermarking uses the fixed quantization step size for the host signal.This scheme is not robust against geometric distortions and may lead to poor fidelity in some areas of content.Thus,we proposed a quantization-based image watermarking in the dual tree complex wavelet domain.We took advantages of the dual tree complex wavelets (perfect reconstruction,approximate shift invariance,and directional selectivity).For the case of watermark detecting,the probability of false alarm and probability of false negative were exploited and verified by simulation.Experimental results demonstrate that the proposed method is robust against JPEG compression,additive white Gaussian noise (AWGN),and some kinds of geometric attacks such as scaling,rotation,etc. 展开更多
关键词 Image Watermarking Quantization IndexModulation dual Tree Complex Wavelet Transform JPEG Compression
下载PDF
MULTIPLIER OPERATORS AND EXTREMAL FUNCTIONS RELATED TO THE DUAL DUNKL-SONINE OPERATOR 被引量:1
13
作者 Fethi SOLTANI 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期430-442,共13页
We study the dual Dunkl-Sonine operator tSk,e on Rd and give expression of tSk,t, using Dunkl multiplier operators on Rd, Next, we study the extremal functions fλ, λ〉 0 related to the Dunkl multiplier operators, an... We study the dual Dunkl-Sonine operator tSk,e on Rd and give expression of tSk,t, using Dunkl multiplier operators on Rd, Next, we study the extremal functions fλ, λ〉 0 related to the Dunkl multiplier operators, and more precisely show that {fλ}λ〉0 converges uniformly to tSk,e(f) as λ→0 Certain examples based on Dunkl-heat and Dunkt-Poisson kernels are provided to illustrate the results. 展开更多
关键词 Dunkl transform dual Dunkl-Sonine operator multiplier operators extremalfunction
下载PDF
A Dual Tree Complex Discrete Cosine Harmonic Wavelet Transform (ADCHWT) and Its Application to Signal/Image Denoising 被引量:3
14
作者 M. Shivamurti S. V. Narasimhan 《Journal of Signal and Information Processing》 2011年第3期218-226,共9页
A new simple and efficient dual tree analytic wavelet transform based on Discrete Cosine Harmonic Wavelet Transform DCHWT (ADCHWT) has been proposed and is applied for signal and image denoising. The analytic DCHWT ha... A new simple and efficient dual tree analytic wavelet transform based on Discrete Cosine Harmonic Wavelet Transform DCHWT (ADCHWT) has been proposed and is applied for signal and image denoising. The analytic DCHWT has been realized by applying DCHWT to the original signal and its Hilbert transform. The shift invariance and the envelope extraction properties of the ADCHWT have been found to be very effective in denoising speech and image signals, compared to that of DCHWT. 展开更多
关键词 ANALYTIC DISCRETE COSINE Harmonic WAVELET TRANSFORM ANALYTIC WAVELET TRANSFORM dual TREE Complex WAVELET TRANSFORM DCT Shift Invariant WAVELET TRANSFORM WAVELET TRANSFORM Denoising
下载PDF
Digital Transformation:Reshaping China’s Development Landscape 被引量:11
15
作者 Zheng Jianghuai Zhang Rui Chen Yingwu 《China Economist》 2021年第3期2-23,共22页
The Chinese economy is currently undergoing a digital transformation.New growth drivers are replacing old ones,creating a new development landscape.Countries with strong digital industries will be the first to reap th... The Chinese economy is currently undergoing a digital transformation.New growth drivers are replacing old ones,creating a new development landscape.Countries with strong digital industries will be the first to reap the benefits of digitalization.For China,the transformation to a digital economy is both of inevitability and heterogeneity fueled by dual circulations.Crowded out from more skill-based digitalized sectors,less-skilled labor moves to less digitalized sectors.New capital,industries and technology clusters emerge as new drivers of manufacturing and service sector development.With its large domestic market and industrial competitiveness,China has fostered a new development landscape of“dual circulations”. 展开更多
关键词 digital transformation shift from old to new growth drivers dual circulations”development landscape re-industrialization of output value service-based employment
下载PDF
Variable spot size optical system for a dual-wavelength laser therapy device 被引量:1
16
作者 Ningning Dong Jinjiang Cui Jiangen Xu 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2020年第4期62-68,共7页
The majority of existing high-power laser therapeutic instruments employ a single wavelength for a single target;thus,they do not meet the requirements for clinical treatment.Therefore,this study designs an optical sy... The majority of existing high-power laser therapeutic instruments employ a single wavelength for a single target;thus,they do not meet the requirements for clinical treatment.Therefore,this study designs an optical system for a dual-wavelength high-power laser therapeutic device with a variable spot size.The waist of the short arm of the optical cavity and the G1G2 parameter(G-parameter equivalent cavity method)is calculated using MATLAB software,the spot size and divergence angle on the lens are calculated using an ABCD matrix,and the distance between the treatment spot at different spot sizes and the transformation lens is calculated in order to design the treatment handpiece.Experiments are conducted to analyze the stability at an output power of 532 nm before beam combination and the power loss after beam combination.The results show that the output power stability of the 532-nm beam varies by less than 2%over 150 min,and the loss of both wavelengths is less than 20%,which meets the clinical requirements of the system.The safety performance can meet the requirements of national general standards for medical electrical safety.The proposed dual-wavelength laser therapy instrument has both visible wave and near-infrared wave characteristics;thus,it can accurately target both superficial vessels and vessels with a larger diameter and deeper position.This therapeutic device has the advantages of simple operation,stable and reliable laser output,high security and strong anti-interference ability,and meets the comprehensive clinical treat-ment demands of vascular diseases. 展开更多
关键词 Laser therapy dual wavelength beam combination spot transformation
下载PDF
DISTANCE MEASURING MODELING AND ERROR ANALYSIS OF DUALCCD VISION SYSTEM SIMULATING HUMAN EYES AND NECK 被引量:3
17
作者 Wang XuanyinXiao BaopingPan FengState Key Laboratory of Fluid PowerTransmission and Control,Zhejiang University,Hangzhou 310027, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第4期396-399,共4页
A dual-CCD simulating human eyes and neck (DSHEN) vision system is putforward. Its structure and principle are introduced. The DSREN vision system can perform somemovements simulating human eyes and neck by means of f... A dual-CCD simulating human eyes and neck (DSHEN) vision system is putforward. Its structure and principle are introduced. The DSREN vision system can perform somemovements simulating human eyes and neck by means of four rotating joints, and realize preciseobject recognizing and distance measuring in all orientations. The mathematic model of the DSHENvision system is built, and its movement equation is solved. The coordinate error and measureprecision affected by the movement parameters are analyzed by means of intersection measuringmethod. So a theoretic foundation for further research on automatic object recognizing and precisetarget tracking is provided. 展开更多
关键词 dual-CCD Simulating human eyes and neck (DSHEN) Intersection measure ERRORANALYSIS Homogeneous coordinate transformation
下载PDF
Effect of controlled rolling on the martensitic hardenability of dual phase steel
18
作者 Mohammad Ajmal Masood Ahmed Tindyala Ron Priestner 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2009年第2期165-169,共5页
The C-Mn and C-Mn-Nb steels were thermo-mechanically processed to develop dual phase steel and to study the effect of controlled rolling on the martensitic hardenability of austenite. The steel specimens were intercri... The C-Mn and C-Mn-Nb steels were thermo-mechanically processed to develop dual phase steel and to study the effect of controlled rolling on the martensitic hardenability of austenite. The steel specimens were intercritically annealed at 790℃, rolled at that temperature to the reductions of 10%, 23%, and 47% and immediately cooled at different rates. Quantitative metallography was used to construct the microstructure map, which illustrated that increasing deformation progressively reduced the proportion of new ferrite formed at all cooling rates and increased the amount of martensite at fast and intermediate rates. The martensitic hardenability of austenite remaining after all the rolling reductions was plotted as a function of cooling rates. It was observed that for the austenite-martensite conversion efficiencies greater than about 25%, controlled rolling increased the martensitic hardenability of austenite. 展开更多
关键词 controlled rolling dual phase steel intercritical annealing HARDENABILITY phase transformation
下载PDF
MATHEMATICAL PROBLEMS IN THE INTEGRAL-TRANSFORMATION METHOD OF DYNAMIC CRACK
19
作者 边文凤 王彪 贾宝贤 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第3期252-256,共5页
In the investigation on fracture mechanics,the potential function was introduced, and the moving differential equation was constructed. By making Laplace and Fourier transformation as well as sine and cosine transform... In the investigation on fracture mechanics,the potential function was introduced, and the moving differential equation was constructed. By making Laplace and Fourier transformation as well as sine and cosine transformation to moving differential equations and various responses, the dual equation which is constructed from boundary conditions lastly was solved. This method of investigating dynamic crack has become a more systematic one that is used widely. Some problems are encountered when the dynamic crack is studied. After the large investigation on the problems, it is discovered that during the process of mathematic derivation, the method is short of precision, and the derived results in this method are accidental and have no credibility.A model for example is taken to explain the problems existing in initial deriving process of the integral_transformation method of dynamic crack. 展开更多
关键词 potential function integral transform dynamic crack dual equation
下载PDF
EXACT SOLUTION AND ITS BEHAVIOR CHARACTERISTIC OF NONLINEAR DUAL-POROSITY MODEL
20
作者 同登科 张鸿庆 王瑞和 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第10期1277-1283,共7页
A nonlinear dual-porosity model considering a quadratic gradient term is presented. Assuming the pressure difference between matrix and fractures as a primary unknown, to avoid solving the simultaneous system of equat... A nonlinear dual-porosity model considering a quadratic gradient term is presented. Assuming the pressure difference between matrix and fractures as a primary unknown, to avoid solving the simultaneous system of equations, decoupling of fluid pressures in the blocks from the fractures was furnished with a quasi-steady-state flow in the blocks. Analytical solutions were obtained in a radial flow domain using generalized Hankel transform. The real value cannot be gotten because the analytical solutions were infinite series. The real pressure value was obtained by numerical solving the eigenvalue problem. The change law of pressure was studied while the nonlinear parameters and dual-porosity parameters changed, and the plots of typical curves are given. All these result can be applied in well test analysis. 展开更多
关键词 nonlinear dual porosity Hankel transform analytical solution pressure cuI've
下载PDF
上一页 1 2 82 下一页 到第
使用帮助 返回顶部