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基于双分支编码的闭环分割网络

计算机系统应用 2024年第1期33卷 110-118页

作者：任玉涛程远志青岛科技大学信息科学技术学院青岛266061

Transformer模型中,卷积视觉转换器(CvT)具备同时提取图像的局部和全局特征的能力而受到关注.对于腹部器官分割问题,为了解决CNN模型分割目标边界轮廓模糊不清的问题,提出了一种新颖的基于CvT和CNN的双分支闭环分割模型DBLNet.模型利用... 详细信息

Transformer模型中,卷积视觉转换器(CvT)具备同时提取图像的局部和全局特征的能力而受到关注.对于腹部器官分割问题,为了解决CNN模型分割目标边界轮廓模糊不清的问题,提出了一种新颖的基于CvT和CNN的双分支闭环分割模型DBLNet.模型利用形状先验和预测结果的分割轮廓显式监督并指导网络学习过程.模型包括:轮廓提取编码模块(CEE)、边界形状分割网络(BSSN)和闭环结构.CEE模块首次利用改造的3D CvT和3D门控卷积层(GCL)捕获多层级轮廓特征,并辅助BSSN训练.BSSN模块设计形状特征融合模块(SFF)同时捕获目标区域和轮廓特征,推动CEE训练拟合.闭环结构使得双分支的分割结果互相反馈并辅助对方的训练.DBLNet在BTCV排行榜上测试,平均Dice得分为0.878,排名第13位;在临床医院数据进行应用测试,表现出强大的性能.

关键词：腹部器官边缘轮廓双分支编码器闭环结构卷积视觉转换器医学影像处理特征融合图像分割

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基于多空间信息提取的级联分块配准模型

计算机系统应用 2024年第2期33卷 125-133页

作者：王南南程远志青岛科技大学信息科学技术学院青岛266061 哈尔滨工业大学(威海)信息科学与工程学院威海264209

在基于深度学习的医学图像配准中,当医学图像中包含多种组织类型时,不同组织之间结构的不同可能会导致网络配准的精度下降,特别是在复杂形变区域,如组织的交界处和病变区域,精准的配准变得更加困难,现有的配准算法对复杂形变区域的关注... 详细信息

在基于深度学习的医学图像配准中,当医学图像中包含多种组织类型时,不同组织之间结构的不同可能会导致网络配准的精度下降,特别是在复杂形变区域,如组织的交界处和病变区域,精准的配准变得更加困难,现有的配准算法对复杂形变区域的关注度不高,导致配准精度较低.同时现有的配准网络无法同时对图像的局部和全局空间信息进行捕获,导致网络的鲁棒性不够,在迁移到其他器官的配准工作中时配准准确率低.为了解决上述的问题,本文提出一种基于多空间信息提取的级联分块配准模型,本模型可以有效利用输入图像的局部和空间信息,并通过分块融合的技术,将医学图像进行分块并依次对每个图像进行精细配准生成相应的形变场块,在模型的最后阶段将生成的形变场块进行融合还原,以增强网络对局部复杂形变区域的配准强度.实验结果表明,所提方法不仅在脑部配准上有所提升,并且在其他人体部位的配准中也有较好的表现,提高了医学图像配准的准确性和可靠性,为临床医生提供更好的诊断和治疗支持.

关键词：医学影像级联网络自注意力机制分块融合信息提取注意力机制图像融合

IUINet:基于Shift的双流映射3D医学分割模型

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计算机系统应用 2024年第1期33卷 141-147页

作者：朱庚鑫程远志刘豪青岛科技大学信息科学技术学院青岛266061

为了提高特征融合,我们设计了动态全连接层(DyFC),该方法重新定义了权重和偏置,使用基向量来代表新的权重和偏置,基向量的系数是根据每一个输入特征进行学习得到的,权重和偏置不再是共享的,而是特有的,这对于每一个特征的表达更具有专向... 详细信息

为了提高特征融合,我们设计了动态全连接层(DyFC),该方法重新定义了权重和偏置,使用基向量来代表新的权重和偏置,基向量的系数是根据每一个输入特征进行学习得到的,权重和偏置不再是共享的,而是特有的,这对于每一个特征的表达更具有专向性.在本文中,我们提出了一种双流映射结构模型***是通过3DShift操作、空间可分离卷积的组合来实现医学图像分割任务,同时保持精度和效率之间的平衡.所提出来的IUINet遵循编码器-解码器结构,其中编码器一部分包含Shift操作、逐点Conv1×1操作,另一部分包含空间可分离卷积操作.IUINet运用了多尺度输入以及多尺度特征映射层,提高反向传播速度,降低反向传播的平均距离.提高模型的精确度,增加模型泛化能力,减少过拟合.

关键词： Shift 基向量动态全连接层医学图像分割

Microstructure and mechanical properties of Ti/Al/Ti clad plates prepared via powder-in-tube method

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Journal of Iron and Steel Research(International) 2024年第3期31卷 670-687页

作者： Xian-lei Hu Qin-cheng Xie Yi yuan Ying zhi State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina Suzhou Dongbao Haixing Metal Material Technology Co. Ltd.Suzhou 215600JiangsuChina School of Material Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina

The Ti/Al/Ti clad plates exhibit a broad spectrum of potential ***,the conventional techniques of hot-pressing composite and explosive composite are intricate and environmentally hazardous.A novel method was introduced for preparing clad plates,namely,the powder-in-tube *** method involves a combination of cold rolling,annealing at a temperature of 550℃,and double *** morphology of the intermetallic compound layer was analyzed through the utilization of interface stripping test,tensile test,and microscopic *** interface morphology,interface bonding properties,tensile fracture structures,and properties of plates under the first and second rolling were compared,along with the effects of intermetallic compounds on the interface *** results indicate that the powder-in-tube method,when annealed at 550℃,can produce a composite plate featuring a complete and uniform Ti/Al *** obtained plate exhibits a peeling strength of 21.5 N/mm,tensile strength of 424 MPa,and elongation of 11.5%.Furthermore,a systematic analysis was conducted to determine the causes of performance degra-dation observed during annealing at temperatures of 600 and 650℃.

关键词： Powder-in-tube method-Ti/Al/Ti clad plate Annealing Cold rolling-Mechanical property

Effect of lanthanum on inclusions in non-oriented electrical steel slabs

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1680-1691页

作者： Qiang Ren zhi-yuan Hu Yun-xia Liu Wei-cheng Zhang Zi-qi Gao Li-feng Zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Research and Development Department Shougang Zhixin Qian'an Electromagnetic Material Co.Ltd.Qian'an 064400HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The effect of lanthanum on the characteristics of inclusions in the slab of non-oriented electrical steels was investigated through industrial trials and thermodynamic *** number,size,and chemical composition of inclusions in the surface,one-quarter of thickness and the center of slabs with and without lanthanum addition were statistically analyzed using an automatic inclusion analysis *** the lanthanum-free slab,inclusions were predominately ***_(2)O_(3),MgO,and AlN as well as a small number of Al_(2)O_(3)-MgO-CaO and *** number densities of oxide inclusions and AlN decreased from the surface to the center of the slab,which was ascribed to the difference in cooling intensity during the continuous *** the steel with lanthanum addition,inclusions were modified into LaAlO_(3) and La_(2)O_(2)S and gradually transformed into dual-phase MgO-La_(2)S3 with an increasing distance from the slab surface due to the reaction between the lanthanum-containing inclusion and the steel *** uneven distribution of oxide inclusions along the thickness of the slab was eliminated in the lanthanum-bearing slab because the dissolved oxygen was remarkably decreased by ***-bearing inclusions were more likely to agglomerate AlN by inducing the heterogeneous nucleation of AlN on their surface,while small-size ***_(2)O_(3) inclusions hardly showed a coarsening effect on the size of AlN.

关键词： Lanthanum-Inclusion Non-oriented electrical steel Aluminum nitride Heterogenous nucleation

A multi-mechanism numerical simulation model for CO_(2)-EOR and storage in fractured shale oil reservoirs

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Petroleum Science 2024年第3期21卷 1814-1828页

作者： yuan-Zheng Wang Ren-Yi Cao zhi-Hao Jia Bin-Yu Wang Ming Ma Lin-Song cheng College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China John&Willie Leone Department of Energy&Mineral Engineering The Pennsylvania State UniversityUniversity Park16802PA.USA

Under the policy background and advocacy of carbon capture,utilization,and storage(CCUS),CO_(2)-EOR has become a promising direction in the shale oil reservoir *** multi-scale pore structure distribution and fracture structure lead to complex multiphase flow,comprehensively considering multiple mechanisms is crucial for development and CO_(2) storage in fractured shale *** this paper,a multi-mechanism coupled model is developed by *** to the traditional Eclipse300 and MATLAB Reservoir Simulation Toolbox(MRST),this model considers the impact of pore structure on fluid phase behavior by the modified Peng—Robinson equation of state(PR-EOS),and the effect simultaneously radiate to Maxwell—Stefan(M—S)diffusion,stress sensitivity,the nano-confinement(NC)***,a modified embedded discrete fracture model(EDFM)is used to model the complex fractures,which optimizes connection types and half-transmissibility calculation approaches between non-neighboring connections(NNCs).The full implicit equation adopts the finite volume method(FVM)and Newton—Raphson iteration for discretization and *** model verification with the Eclipse300 and MRST is *** results show that the interaction between the mechanisms significantly affects the production performance and storage *** effect of molecular diffusion may be overestimated in oil-dominated(liquid-dominated)shale *** well spacing and injection gas rate are the most crucial factors affecting the production by sensitivity ***,the potential gas invasion risk is *** model provides a reliable theoretical basis for CO_(2)-EOR and sequestration in shale oil reservoirs.

关键词： CO_(2)-EOR CO_(2)storage Shale oil reservoir Complex fracture model Multiple mechanisms

Synergic action of linear dispersion, second-order nonlinearity, and third-order nonlinearity in shaping the spectral profile of a femtosecond pulse transporting in a lithium niobate crystal

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Photonics Research 2024年第4期12卷 774-783页

作者： LIHONG HONG yuanyuan LIU zhi-yuan LI State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

We present a detailed theoretical and numerical analysis on the temporal-spectral-spatial evolution of a highpeak-power femtosecond laser pulse in two sets of systems:a pure lithium niobate(LN)plate and a periodically poled lithium niobate(PPLN)*** develop a modified unidimensional pulse propagation model that considers all the prominent linear and nonlinear processes and carried out the simulation process based on an improved split-step Fourier transformation *** theoretically analyze the synergic action of the linear dispersion effect,the second-order nonlinearity(2nd-NL)second-harmonic generation(SHG)effect,and the third-order nonlinearity(3rd-NL)self-phase modulation(SPM)effect,and clarify the physical mechanism underlying the peculiar and diverse spectral broadening patterns previously reported in LN and PPLN thin plate *** analysis and discussion provides a deeper insight into the synergetic contribution of these linear and nonlinear effects brought about by the interaction of a femtosecond laser pulse with the LN nonlinear crystal and helps to draw a picture to fully understand these fruitful optical physical processes,phenomena,and laws.

关键词： pulse nonlinearity lithium

A synthesis of the Cretaceous wildfire record related to atmospheric oxygen levels?

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Journal of Palaeogeography 2024年第1期13卷 149-164页

作者： Da-Wei Lü Wen-Xu Du zhi-Hui Zhang yuan Gao Tian-Tian Wang Jin-cheng Xu Ao-Cong Zhang cheng-Shan Wang Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Sciences and EngineeringShandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina School of Earth Sciences and Resources China University of GeosciencesBejing 100083China Institute of Earth Sciences China University of Geosciences(Bejing)Beijing 100083China

The Cretaceous was a significant greenhouse period in Earth's history with higher atmospheric CO_(2) levels and temperatures than today. Although evidence of combustion has been widely described from the Cretaceous deposits, our understanding of the spatiotemporal diversification pattern and process of the Cretaceous wildfires is still limited. In this study, we comprehensively synthesize a total of 271 published Cretaceous wildfire occurrences based on the by-products of burning, including fossil charcoal, pyrogenic inertinite(fossil charcoal in coal), and pyrogenic polycyclic aromatic hydrocarbons(PAHs). Spatially, the dataset shows a distinctive distribution of reported wildfire evidence characterized by high concentration in the middle latitudinal areas of the Northern Hemisphere(30°N-60°N) over the Cretaceous. Temporally, an overall increasing trend of the reported wildfire data from the Early Cretaceous to the Late Cretaceous is coincident with higher atmospheric O_(2) levels. However, the spatial and temporal patterns may result from many types of factors, such as taphonomy, preservation, and researcher biases, instead of a real picture of the Cretaceous wildfire evolution. To better understand the spatiotemporal diversification of the Cretaceous wildfire, more investigations on the record of wildfire occurrences during this period would be necessary in the future.

关键词： Wildfire Cretaceous Atmospheric oxygen Taphonomy Charcoal

Boundary Points,Minimal L^(2)Integrals and Concavity PropertyⅢ—Linearity on Riemann Surfaces and Fibrations over Open Riemann Surfaces

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2091-2152页

作者： Qi An GUAN zhi Tong MI Zheng yuan School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China School of Mathematics and Statistics Beijing Jiaotong UniversityBeijing 100044P.R.China Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China

In this article,we consider a modified version of minimal L^(2) integrals on sublevel sets of plurisubharmonic functions related to modules at boundary points,and obtain a concavity property of the modified *** applications,we give characterizations for the concavity degenerating to linearity on open Riemann surfaces and on fibrations over open Riemann surfaces.

关键词： Minimal L^(2)integrals plurisubharmonic functions boundary points weakly pseudoconvex Kähler manifold