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基于CNN和Transformer交叉教学的半监督医学图像分割

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陕西科技大学学报 2025年第1期43卷 185-192页

作者：杨云胡雯青杨虹吴亚男陕西科技大学电子信息与人工智能学院陕西西安710021 西安富德医疗电子有限公司陕西西安710075 西安计量技术研究院陕西西安710199

由于医学图像分割领域缺乏高质量的标注数据,半监督学习方法在医学图像语义分割任务中受到高度重视.为了充分利用卷积神经网络(Convolutional Neural Network,CNN)和Transformer在半监督学习中的优势,本文提出一种基于CNN与Transformer... 详细信息

由于医学图像分割领域缺乏高质量的标注数据,半监督学习方法在医学图像语义分割任务中受到高度重视.为了充分利用卷积神经网络(Convolutional Neural Network,CNN)和Transformer在半监督学习中的优势,本文提出一种基于CNN与Transformer交叉教学的半监督医学图像分割方法.该方法将经典的深度协同训练从一致性正则化简化为交叉教学,利用循环伪标签方案使两个网络的预测差异转换为无监督损失,以鼓励两个网络具有一致的低熵预测.所提方法在ISIC 2018数据集上进行实验,在采用20%的标注比例时,Dice系数和Jaccard系数分别达到87.25%和79.17%,相比于监督U-Net++的训练结果分别提升了2.89%和3.53%,并且优于目前主流的半监督学习方法,验证了所提方法在半监督医学图像分割上的有效性和泛化性.

关键词：半监督学习图像语义分割交叉教学循环伪标签

维普期刊数据库博看期刊

Three-dimensional thermohaline anomaly structures of rings in the Kuroshio Extension region

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Acta Oceanologica Sinica 2020年第3期39卷 25-35页

作者： ya’nan Ding Chunsheng Jing Third Institute of Oceanography Ministry of Nature ResourcesXiamen 361005China

Using AVISO satellite altimeter observations during 1993–2015 and a manual eddy detection method, a total of 276 anticyclonic rings and 242 cyclonic rings shed from the Kuroshio Extension(KE) were identified, and their three-dimensional(3D) anomaly structures were further reconstructd based on the Argo float data and the Japan Agency for Marine-Earth Science and Technology(JAMSTEC) cruise and buoy data through an interpolation method. It is found that the cyclonic(anticyclonic) rings presented consistent negative(positive) anomalies of potential temperature;meanwhile the relevant maximum anomaly center became increasingly shallow for the cyclonic rings whereas it went deeper for the anticyclonic rings as the potential temperature anomaly decreased from the west to the east. The above deepening or shoaling trend is associated with the zonal change of the depth of the main thermocline. Moreover, the composite cold ring between 140° and 150°E was found to exhibit a double-core vertical structure due to the existence of mode water with low potential vorticity. Specifically, a relatively large negative(positive) salinity anomaly and a small positive(negative) one appeared for the composite cyclonic(anticyclonic) ring at the depth above and below 600 m, respectively. The underlying driving force for the temperature and salinity anomaly of the composite rings was also attempted, which varies depending on the intensity of the background current and the temperature and salinity fields in different areas of the KE region, and the rings’ influences on the temperature and salinity could reach deeper than 1 000 m on average.

关键词： Kuroshio Extension pinched-off ring thermohaline anomaly three-dimensional structure composite eddy

Reliability analysis on civil engineering project based on integrated adaptive simulation annealing and gray correlation method

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Frontiers of Structural and Civil Engineering 2016年第4期10卷 462-471页

作者： Xiao-ping BAI ya-nan LIU System Engineering Research Institute School of Management Xi 'an University of Architecture & Technology Xi 'an 710055 China

Dynamic reliability is a very important issue in reliability research. The dynamic reliability analysis for the project is still in search of domestic and international research in the exploration stage. By now, dynamic reliability research mainly concentrates on the reliability assessment; the methods mainly include dynamic fault tree, extension of event sequence diagram and Monte Carlo simulation, and et al. The paper aims to research the dynamic reliability optimization. On the basis of analysis of the four quality influence factors in the construction engineering, a method based on gray correlation degree is employed to calculate the weights of factors affecting construction process quality. Then the weights are added into the reliability improvement feasible index （RIFI）. Furthermore, a novel nonlinear programming mathematic optimization model is established. In the Insight software environment, the Adaptive Simulated Annealing （ASA） algorithm is used to get a more accurate construction subsystem optimal reliability under different RIFI conditions. In addition, the relationship between construction quality and construction system reliability is analyzed, the proposed methods and detailed processing can offer a useful reference for improving the construction system quality level.

关键词： civil engineering dynamic reliability grey relational degree adaptive simulated annealing algorithm

A mathematical model of cortical bone remodeling at cellular level under mechanical stimulus

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Acta Mechanica Sinica 2012年第6期28卷 1678-1692页

作者： Qing-Hua Qin ya-nan Wang Research School of Engineering The Australian National University

A bone cell population dynamics model for cor- tical bone remodeling under mechanical stimulus is devel- oped in this paper. The external experiments extracted from the literature which have not been used in the creation of the model are used to test the validity of the model. Not only can the model compare reasonably well with these ex- perimental results such as the increase percentage of final values of bone mineral content （BMC） and bone fracture en- ergy （BFE） among different loading schemes （which proves the validity of the model）, but also predict the realtime devel- opment pattern of BMC and BFE, as well as the dynamics of osteoblasts （OBA）, osteoclasts （OCA）, nitric oxide （NO） and prostaglandin E2 （PGE2） for each loading scheme, which can hardly be monitored through experiment. In conclusion, the model is the first of its kind that is able to provide an in- sight into the quantitative mechanism of bone remodeling at cellular level by which bone cells are activated by mechan- ical stimulus in order to start resorption/formation of bone mass. More importantly, this model has laid a solid foun- dation based on which future work such as systemic control theory analysis of bone remodeling under mechanical stimu- lus can be investigated. The to-be identified control mecha- nism will help to develop effective drugs and combined non- pharmacological therapies to combat bone loss pathologies. Also this deeper understanding of how mechanical forces quantitatively interact with skeletal tissue is essential for the generation of bone tissue for tissue replacement purposes in tissue engineering.

关键词： Cortical bone remodeling Cell population dy-namics Mechanotransduction Mechanosensitivity Bonefracture energy - Bone mineral content

Experimental Study on Cooling Down Process of a Nitrogen-Charged Cryogenic Loop Heat Pipe

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Journal of Thermal Science 2023年第1期32卷 153-165页

作者： ZHAO ya'nan yaN Tao LIANG Jingtao Key Laboratory of Space Energy Conversion Technology Technical Institute of Physics and ChemistryChinese Academyof SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Cryogenic loop heat pipes are highly efficient heat transfer devices at cryogenic temperature range,which have promising application prospects in satellites,spacecrafts,electronics,and so *** down process is a most critical process for a CLHP before *** present,secondary loop is a major way for a CLHP to fulfil cooling down and most studies are concentrated on heat transfer characteristics during normal ***,few investigations have been carried out on the cooling down *** this paper,the cooling down process of a nitrogen-charged CLHP assisted with a secondary loop was experimentally investigated.A simple qualitative approach to estimate the cooling down time was proposed according to the law of conservation of *** two flow paths of the working fluid in the CLHP during the cooling down process were *** studies on the cooling down process with various secondary heat loads and working fluid inventory were presented in *** the increase of secondary heat load,the elapsed time of Stage III decreased significantly due to the larger mass flow rate in Path *** addition,the effect of the working fluid inventory on the cooling down time was generally small in the range from 2.99 MPa to 3.80 ***,with 2.80 MPa working fluid inventory,it required much longer cooling down time,which was because of the lack of liquid in the CLHP with low working fluid ***,the influence of gravity on the temperature variation of the components during the experiments was *** work is beneficial for better understanding of the cooling down process and optimizing of CLHPs.

关键词： cryogenic loop heat pipe secondary loop cooling down heat transfer

Experimental Investigation on Thermal Characteristics of Long Distance Loop Heat Pipes

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Journal of Thermal Science 2022年第3期31卷 741-750页

作者： ZHAO ya’nan yaN Tao LIANG Jingtao Key Laboratory of Space Energy Conversion Technology Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100190China

Loop heat pipes(LHPs)are attractive two-phase thermal control devices for satellites,electronics and many other *** are capable of transporting heat efficiently for long distances up to several meters at any *** paper investigated the heat transfer characteristics of loop heat pipes with long distances and small diameter transport *** stainless steel tubes of 2 mm and 3 mm in inner diameters were chosen as liquid lines and vapor lines of the *** local thermal resistances in the evaporator of the 6 m-LHP were researched and analyzed,which indicated that the thermal resistance between the aluminum block and the vapor in the vapor channel accounted for a major proportion of the total thermal *** effect of heat sink temperatures on the performance of the 6 m-LHP were compared with 10°C,15°C,20°C and 25°C cooling water ***,the thermal characteristics of LHPs with transport distances of 2 m and 16 m were also experimentally *** 16 m-LHP could achieve a heat transfer capacity of 100 W and the 2 m-LHP could reach more than 339 W,on the premise of the evaporator temperature below 100°*** thermal resistance of the 2 m-LHP could achieve 0.125°C/W.

关键词： loop heat pipe thermal management heat transport long distance thermal resistance

Flexible double narrowband near-infrared photodetector based on PMMA/core-shell upconversion nanoparticle composites

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Journal of Rare Earths 2022年第2期40卷 211-217,I0002页

作者： ya’nan Ji Donglei Zhou nan Wang nan Ding Wen Xu Hongwei Song State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China

Flexible narrowband near infrared(NIR)photodetectors(PDs)are urgently in demand in the fastdeveloping era of flexible electronics,due to their crucial roles in various innovative ***,we designed and synthesized the core-shell structured NaYF4:Yb^(3+),Er^(3+)@NaYF4:Nd^(3+)upconversion nanoparticles(UCNPs),which can be pumped by the 808 and 980 nm *** upconversion luminescence(UCL)are significantly enhanced after being assembled with the opal photonic crystals(OPCs)due to the photonic crystal effect,with 55 and 48 folds of enhancement factors under illuminations of 808 and 980 nm lights,*** on this hybrid,the flexible narrowband PDs were successfully fabricated on the PET substrate with the structure of OPCs/NaYF4:Yb^(3+),Er^(3+)@Nd^(3+)/MAPbl3,which displays excellent detection performance to double narrowband NIR light(808 and 980 nm)benefiting from the amplified UCL,with responsivity of 8.79 and 7.39 A/W,detectivity of 3.01×10^(11)and2.68×10^(11)cm·Hz^(1/2)/W for 808 and 980 nm lights detection respectively,along with short response time in the range of 120-160 ***,the OPCs/NaYF4:Yb^(3+),Er^(3+)@NaYF4:Nd^(3+)/MAPbI3 double narrowband PDs display low photodetection power threshold(0.05 W/cm2),outstanding flexibility,prominent moisture resistance,and good long-time *** work displays a new concept of narrowband NIR PDs,which open a new field for specific NIR light detections.

关键词： Upconversion luminescence Upconversion enhancement Narrow-band near-infrared photodetection Flexible photodetectors Rare earths

Perturbed magnetic field of an infinite plate with a centered crack

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Acta Mechanica Sinica 2011年第2期27卷 259-265页

作者： Fei Qin yang Zhang ya-nan Liu College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology 100124 Beijing China

Deforming a cracked magnetoelastic body in a magnetic field induces a perturbed magnetic field around the crack. The quantitative relationship between this perturbed field and the stress around the crack is crucial in developing a new generation of magnetism-based nondestructive testing technologies. In this paper, an analytical expression of the perturbed magnetic field induced by structural deforma- tion of an infinite ferromagnetic elastic plate containing a centered crack in a weak external magnetic field is obtained by using the linearized magnetoelastic theory and Fourier transform methods. The main finding is that the perturbed magnetic field intensity is proportional to the applied tensile stress, and is dominated by the displacement gradient on the boundary of the magnetoelastic solid. The tangential component of the perturbed magnetic-field intensity near the crack exhibits an antisymmetric distribution along the crack that reverses its direction sharply across its two faces, while the normal component shows a symmetric distribution along the crack with singular points at the crack tips.

关键词： Magnetoelasticity Crack Perturbed magnetic field Fourier transform method Nondestructive testing

二维光晶格中旋转玻色-爱因斯坦凝聚基态中的涡旋分布

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原子与分子物理学报 2025年第1期42卷 118-126页

作者：张志强王平平吕亚南郑州商学院大学物理教研室郑州451200

利用多重网格预条件共轭梯度法,研究了囚禁在二维光晶格与谐振势组成的复合势阱中的旋转玻色-爱因斯坦凝聚体中的涡旋分布,探讨了光晶格深度、晶格常数和凝聚体旋转频率对旋转凝聚体中涡旋分布的影响.结果表明,由于光晶格势阱的引入,凝... 详细信息

利用多重网格预条件共轭梯度法,研究了囚禁在二维光晶格与谐振势组成的复合势阱中的旋转玻色-爱因斯坦凝聚体中的涡旋分布,探讨了光晶格深度、晶格常数和凝聚体旋转频率对旋转凝聚体中涡旋分布的影响.结果表明,由于光晶格势阱的引入,凝聚体中产生涡旋,且涡旋位于外部势阱极小值处.随着光晶格势阱深度的增加,凝聚体集聚在光晶格势阱的底部,形成格点状分布,其中的涡旋形成涡旋对,并融合形成更大的涡旋.在晶格常数较小时,凝聚体中涡旋分布形成类似Abrikosov涡旋晶格,随着晶格常数的增加,凝聚体中涡旋的分布形式出现多样化,出现了内中外三层结构.随着旋转频率的增加,凝聚体中涡旋数目也随之增加,涡旋分布也更加复杂和富于变化,凝聚体密度分布范围也随着旋转频率的增加而扩展.当凝聚体旋转频率接近外部谐振势阱的谐振频率,即凝聚体处于最低朗道能级近似时,其中的涡旋数量大幅度增加,且出现涡旋成对组合与融合现象,并形成了涡旋斑图花纹.

关键词：波色-爱因斯坦凝聚涡旋二维光晶格复合势阱