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Semantic Segmentation of Lumbar vertebrae Using Meijering U-Net(MU-Net)on Spine Magnetic Resonance Images

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 733-757页

作者： Lakshmi S v v Shiloah Elizabeth Darmanayagam Sunil Retmin Raj Cyril Department of Computer Science and Engineering College of Engineering GuindyAnna UniversityChennai600025India Department of Information technology Madras Institute of TechnologyAnna UniversityChrompetChennai600044India

Lower back pain is one of the most common medical problems in the world and it is experienced by a huge percentage of people *** to its ability to produce a detailed view of the soft tissues,including the spinal cord,nerves,intervertebral discs,and vertebrae,Magnetic Resonance Imaging is thought to be the most effective method for imaging the *** semantic segmentation of vertebrae plays a major role in the diagnostic process of lumbar *** is difficult to semantically partition the vertebrae in Magnetic Resonance Images from the surrounding variety of tissues,including muscles,ligaments,and intervertebral discs.U-Net is a powerful deep-learning architecture to handle the challenges of medical image analysis tasks and achieves high segmentation *** work proposes a modified U-Net architecture namely MU-Net,consisting of the Meijering convolutional layer that incorporates the Meijering filter to perform the semantic segmentation of lumbar vertebrae L1 to L5 and sacral vertebra ***-colour mask images were generated and used as ground truth for training the *** work has been carried out on 1312 images expanded from t1-weighted mid-sagittal MRI images of 515 patients in the Lumbar Spine MRI Dataset publicly available from Mendeley *** proposed MU-Net model for the semantic segmentation of the lumbar vertebrae gives better performance with 98.79%of pixel accuracy(PA),98.66%of dice similarity coefficient(DSC),97.36%of Jaccard coefficient,and 92.55%mean Intersection over Union(mean IoU)metrics using the mentioned dataset.

关键词： Computer aided diagnosis(CAD) magnetic resonance imaging(MRI) semantic segmentation lumbar vertebrae deep learning U-Net model

公交优先条件下小汽车出行向公交转移的预测模型研究(英文)

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交通运输系统工程与信息 2009年第6期9卷 120-129页

作者： vEDAGIRI P. ARASAN v.t. 印度理工学院孟买分校土木工程系印度孟买400076 印度理工学院马德拉斯分校土木工程系印度钦奈600036

研究印度城市道路上设置公交专用道后小汽车出行向公交转移的可能性.借助新的混合交通流仿真模型测定设置公交专用道后公交服务水平改善状况.基于陈述偏好入户调查的抽样数据,本文还引入其他影响出行方式转移的变量,标定出行方式选择二... 详细信息

研究印度城市道路上设置公交专用道后小汽车出行向公交转移的可能性.借助新的混合交通流仿真模型测定设置公交专用道后公交服务水平改善状况.基于陈述偏好入户调查的抽样数据,本文还引入其他影响出行方式转移的变量,标定出行方式选择二元Logit模型.根据实际和预测数据,确定了公交服务水平改善条件下小汽车出行向公交转移的一系列主要影响因素.基于两种方式出行时间差,绘制出行方式转换概率曲线,并为多变量宽值域条件下交通方式转移的预测提供一种易于操作的方法.

关键词：公共交通混合交通流出行时间公交专用道出行方式选择模型

地球的工程地质结构——内容、成因、判别标志及空间分布(英文)

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地学前缘 2007年第2期14卷 257-267页

作者： v.t. trofimov.t.I. Averkina Lomonosov Moscow State University

文中定义了“工程地质结构”这一术语,讨论了其内容、成因、判别标志与依据、谱系分类及全球实际系列,并对全球及各大洲的超巨型、巨型、大型、中型工程地质结构的分布规律进行了描述。

关键词：工程地质结构超巨型、巨型、大型及中型工程地质结构地球工程地质结构实际系列

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岩石圈的生态作用(英文)

地学前缘 2002年第4期9卷 293-303页

作者： v.t. tROFIMOv Lomonosov Moscow State University

文章确定了“岩石圈的生态作用”这一概念的内涵 ,考虑了作用的分类 ;阐述了岩石圈的各种生态作用 ,它们分别是资源的、地球动力学的、地球化学的和地球物理的生态作用 ;阐明了在地球演化过程中和工程技术造成的影响之下这些生态作用形... 详细信息

文章确定了“岩石圈的生态作用”这一概念的内涵 ,考虑了作用的分类 ;阐述了岩石圈的各种生态作用 ,它们分别是资源的、地球动力学的、地球化学的和地球物理的生态作用 ;阐明了在地球演化过程中和工程技术造成的影响之下这些生态作用形成的规律 ;提出了有关这些生态作用的研究课题。

关键词：生态地质学岩石圈的生态作用岩石圈的资源的、地球动力学的、地球化学的和地球物理的生态作用关于岩石圈生态作用的科学

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混合交通流密度测定方法研究(英文)

交通运输系统工程与信息 2010年第4期10卷 50-61页

作者： ARASAN v.t. DHIvYA G．印度理工学院马德拉斯分校土木工程系印度钦奈600036

交通流密度是衡量道路服务水平的指标之一.当交通流中车辆长度和速度变化较大时,占有率则可以更好地反映交通流密度状况.占有率的测定能够考虑到车辆的长度和速度变化,但是其值受到测量区域长度的影响,并且在混合交通情况下测量值缺乏... 详细信息

交通流密度是衡量道路服务水平的指标之一.当交通流中车辆长度和速度变化较大时,占有率则可以更好地反映交通流密度状况.占有率的测定能够考虑到车辆的长度和速度变化,但是其值受到测量区域长度的影响,并且在混合交通情况下测量值缺乏准确性.对于没有车道行驶规则的混合交通流,应当以整条路段为单位进行交通流分析.因此本文提出了"区域占有率"的概念,且利用仿真技术验证其有效性.对混合交通流条件下的占有率和区域占有率进行比较分析,区域占有率可以更合理地描述混合交通流的密度.同时,得出混合交通条件下的区域占有率和交通流速度关系,证明了混合交通流条件下区域占有率提出的合理性和准确性.

关键词：城市交通密度测定混合交通占有率交通流仿真模型交通量分析

3D Kinematics of Classical Cepheids According to Gaia EDR3 Catalog

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Research in Astronomy and Astrophysics 2023年第4期23卷 1-14页

作者： v.v.Bobylev A.t.Bajkova Pulkovo Astronomical Observ.t.ry St.-Petersburg 196140Russia

the kinematics of about 2000 classical Cepheids of the Milky Way with data from Gaia EDR3 catalog has been *** some of these stars,there are line-of-sight *** the basis of the nonlinear rotation model,the parameters of the rotation curve of the Galaxy were *** circular linear rotation velocity of the near-solar neighborhood around the Galaxy center was v0=236±3 km s^(−1) for the assumed Sun's galactocentric distance R0=8.1±0.1 *** of residual velocities of Cepheids based on the linear Ogorodnikov–Milne model showed the presence of the following significantly different from zero gradients:∂U/∂x,∂U/∂z,∂v/∂x,∂v/∂z and∂W/∂x,which behave differently depending on the selection *** most interesting is the gradient∂W/∂x∼−0.5±0.1 km s^(−1) kpc^(−1)(positive rotation of this star system around the Galactic axis y,Ωy)since the velocities W are free of Galactic *** we have an indirect influence of various effects leading to a perturbation of the vertical velocities of the Galactic disk *** on a simpler model,a more accurate estimate of this rotation is obtained,Ωy=0.51±0.07 km s^(−1) kpc^(−1).

关键词： stars distances-Galaxy kinematics and dynamics-stars variables Cepheids

How Common can the Origin of Clusters Cha Ⅰ, Cha Ⅱ, ∈Cha and η Cha be?

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Research in Astronomy and Astrophysics 2024年第5期24卷 28-34页

作者： v.v.Bobylev A.t.Bajkova Pulkovo Astronomical Observ.t.ry St.-Petersburg 196140Russia

the trajectories of the groupings η Cha,∈Cha and Cha I,Cha II,constructed backward in time,have been *** concluded that the hypothesis about the joint formation of all four of these clusters from one molecular cloud cannot be completely ***,10–15 Myr ago,all these four clusters were located at approximately the same height above the plane of the ***,the gas-dust clouds from which all these four clusters were formed were located on one broad *** is possible that the appearance of the Cha I,Cha II,∈Cha and η Cha clusters may be associated with the impact on such a front of shock waves formed after supernova explosions in the Scorpius–Centaurus *** estimates of the kinematic ages of the clusters Cha I and Cha II are obtained as 0.12±0.19 and 0.05±0.15,*** is shown that the minimum size of the Cha I-north and Cha I-south clusters corresponded to the time of 0.55±0.24 Myr and 0.04±0.18 Myr ago,respectively,and approximately1.5 Myr ago the distance between the trajectories of these two groupings was minimal.

关键词： stars distances-stars kinematics and dynamics-galaxies star formation

tuning the particle size,physical properties,and photocatalytic activ.t. of Ag_(3)PO_(4)materials by changing the Ag^(+)/PO_(4)^(3-)ratio

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Chinese Physics B 2023年第3期32卷 561-568页

作者： Hung N M Oanh L t M Chung D P thang D v Mai v.t.Hang L t Minh N v Center for Nano Science and technology Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi 100000Vietnam Department of Physics Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi 100000Vietnam Hanoi University of Mining and Geology Duc Thang WardNorth Tu Liem DistrictHanoi 100000Vietnam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc VietHanoi 100000Vietnam Faculty of Basic Sciences Hanoi University of Natural Resources and Environment41 A Phu Dien RoadNorth Tu LiemHanoi 100000Vietnam

this study demonstrates the influence of the Ag^(+)/PO_(4)^(3-)ratio in precursor solution on the crystal structural formation,morphology,physical properties,and photocatalytic performance of a Ag_(3)PO_(4)photocatalyst that is fabricated,using a facile precipitation method,from AgNO_(3)and Na2HPO_(4)·12H_(2)*** material characterizations were carried out using x-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive x-ray spectroscopy(EDX),Brunauer–Emmett–teller(BEt)surface area,Fourier transform infrared(FtIR)absorption,Raman scattering,x-ray photoelectron spectroscopy(XPS),Uv-vis absorption,and photoluminescence(PL).the results show that Ag_(3)PO_(4)crystallizes better when the excess PO_(4)^(3-)content increases,and the lattice parameters decrease slightly,while the crystal diameter and the particle size *** change is also observed in the Raman scattering and FtIR spectra with the increase in the vibration frequency of the[PO_(4)]*** compression of the[PO_(4)]unit was also confirmed in the XPS spectra with the shift of P 2p peaks toward higher binding *** photocatalytic results showed that the samples synthesized from excess PO_(4)^(3-)solution exhibited higher photocatalytic performance compared to the sample with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.A sample prepared from the precursor solution with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.5 was optimal for RhB decomposition under both visible light and natural sunlight,completely decomposing 10 ppm RhB after 15 minutes of xenon lamp irradiation and after 60 minutes under solar light *** is attributed to the high crystallinity,small particle size and low electron–hole recombination rate of the sample.

关键词： morphology photocatalytic Ag^(+)/PO_(4)^(3-)ratio visible light

the Planck theory of Sonoluminescence

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Progress in Natural Science:Materials International 1998年第4期8卷 3-5页

作者： t.v.Prevenslik 2E Greenery Court China Discovery Bay Hong Kong

Sonolummescence (SL) may be explained by a theory, called the Planck theory of SL that treats she bubbles as miniature collapsing cav.t.es. During bubble collapse, the Planck energy intrinsic to the cav.t. dimensions is converted to microwave photons that accumulate in the bubble wall molecules. Photons are emitted from the bubble wall molecules as the Planck energy accumulates to electronic levels.

关键词： Sonolluninescence Planck theory IRaser.