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semantic segmentation of Lumbar Vertebrae Using Meijering U-Net(MU-Net)on spine Magnetic Resonance Images

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

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Predicting Maximum Lifespan Limits at Mean Menopausal Age

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Journal of Mathematical Research with Applications 2025年第1期 133-142页

作者： M.sUMATHI s.ANTONy CARLA Department of Mathematics N.M.S.S.Vellaichamy Nadar College Research scholar (Part-time) Madurai Kamaraj University

The age at which a woman enters natural menopause has also been associated to death from any cause. Menopause is a natural component of aging that happens between the ages of 45 and 55, with the average menopausal age being 51. Previous research has revealed the age at which women reach menopause, but there is no evidence to support the link between menopause and longevity. We made a study in assessing the limits of maximum lifespan at menopausal age in our previous article. In this paper, we aim to predict the maximum lifespan of women at mean menopausal age.

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Poverty Volatility and Tax Revenue Instability in Developing Countries

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Fudan Journal of the Humanities and social sciences 2024年第2期17卷 279-311页

作者： sèna Kimm Gnangnon World Trade Organization Rue de Lausanne 154CH-1211Geneva 21Switzerland

This paper complements the relatively few existing studies on the macroeconomic effects of poverty in developing countries, by investigating the effect of poverty volatility on tax revenue instability. The empirical analysis has been conducted using an unbalanced panel dataset of 97 developing countries covering the period of 1980–2017 and primarily the two-step system generalized method of moments estimator. Findings have revealed that least developed countries tend to experience a positive tax revenue instability effect of poverty volatility, while poverty volatility results in lower tax revenue instability in relatively advanced countries. Additionally, poverty volatility dampens the instability of tax revenue when poverty rates are low, and enhances it when countries face a greater extent of external shocks. From a policy perspective, this analysis shows that it would be essential for policymakers to dampen the volatility of poverty rates (notably in countries with high poverty rates) if they were to ensure the stability of tax revenue or reduce its instability, given the adverse effect of tax revenue instability on economic growth.

关键词： Poverty volatility Poverty rates External shocks Tax revenue instability

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soft x-ray tomographic reconstruction of Heliotron J plasma for the study of magnetohydrodynamic equilibrium and stability

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Plasma science and Technology 2019年第6期21卷 72-78页

作者： s PUROHIT y sUZUKI s OHDACHI s yAMAMOTO sOKENDAI The Graduate University for Advanced Studies Toki Gifu 509-5292 Japan national Institute for Fusion science Toki Gifu 509-5292 Japan Institute of Advanced Energy Kyoto University Gokasho Uji Kyoto 611-0011 Japan

The preparation for an experimental soft x-ray tomography study on the Heliotron J (H-J) machine is carried out,with the objectives of evaluating the capability of the current soft x-ray tomographic system in terms of the identification of different mode structures and their poloidal rotation,and the axis shift with different plasma and machine parameters,and fixing the physics goals for the experimental *** preparations were carried out via a simulated soft x-ray data set arising from different plasma conditions,such as magnetic islands,low beta and high *** x-ray tomography (sXT) is performed by the discrete pixel method including singular value decomposition and Phillips-Tikhonov regularization,to obtain clear and smooth *** H-J soft x-ray tomography results from simulated soft x-rays for the equilibrium H-J plasma sensed the magnetic axis shift clearly and an estimate was also *** reconstruction for mode structure m =1/n =1 was obtained along with the realization of the poloidal rotation of the *** reconstruction for the m =2/n =1 mode was not very clear for the current soft x-ray diagnostic *** mode identification was not possible due to the lack of *** sXT from the current soft x-ray diagnostic on H-J,the magnetic axis shift can be estimated and the m =1/n =1 mode can be *** of higher poloidal modes is difficult with the current design.

关键词： Heliotron J tomography soft x-ray magnetohydrodynamics

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Decomposition of labile and recalcitrant coniferous litter fractions affected by temperature during the growing season

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Journal of Forestry Research 2020年第4期31卷 1115-1121页

作者： Veronika Jílková Kristyna Dufková Tomás Cajthaml Na Sádkách 7CeskéBudějovice 37005Czech Republic Faculty of science Masaryk UniversityKotlárská267/2Brno 61137Czech Republic Institute for Environmental studies Charles University in PragueBenátská2Prague 12801Czech Republic Institute of Microbiology Czech Academy of SciencesVídeňská1083Prague 14220Czech Republic

Temperate coniferous forest soils are considered important sinks of soil organic carbon(C).Fresh C inputs may,however,affect soil microbial activity,leading to increased organic matter decomposition and carbon dioxide *** consists of labile and recalcitrant fractions which are thought to be utilized by distinct microbial communities and at different rates during the growing *** this study,we incubated the whole litter(LC+RC),the labile(LC)and the recalcitrant(RC)fractions with the coniferous soil at two temperatures representing spring/autumn(10℃)and summer(20℃)for one *** respiration and microbial community composition were regularly determined using phospholipid fatty acids as *** LC fraction greatly increased soil respiration at the beginning of the incubation period but this effect was rather *** effect of the RC fraction persisted longer and,together with the LC+RC fraction,respiration increased during the whole incubation *** of the RC fraction was more strongly affected by higher temperatures than decomposition of the more labile fractions(LC and LC+RC).However,when we consider the relative increase in soil respiration compared to the dH2 O treatment,respiration increased more at a lower temperature,suggesting that available C is more important for microbial metabolism at lower *** C was added only once in our study,no changes in microbial community composition were detected,possibly because the microbial community is adapted to relatively low amounts of additional C such as the amounts naturally found in litter.

关键词： Temperate forest Picea abies soil respiration Hot water-extractable carbon PLFA (phospholipid fatty acids)

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Effect of Temperature on Material Transfer Behavior at Different stages of Friction stir Welded 7075-T6 Aluminum Alloy

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Journal of Materials science & Technology 2013年第10期29卷 955-960页

作者： s.D.Ji y.y.Jin y.M.yue s.s.Gao y.X.Huang L.Wang Faculty of Aerospace Engineering Shenyang Aerospace University state Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology

In this work, the morphologies of weld of 7075-T6 aluminum alloy via friction stir welding （FsW） were analyzed by optical microscopy, the temperature field was attained by numerical simulation, and the effect of temperature on material transfer behavior in the thermal-mechanical affected zone （TMAZ） at different stages was mainly investigated. The FsW process consists of three stages. It is very interesting to find that the maximum transfer displacement of material appears at the final stage of welding process, then at the stable stage and at the initial stage, which results from the difference of peak temperatures at different stages. At any stage, the material in TMAZ near the surface of weld transfers downwards, the material in the middle of weld moves upwards and the material near the bottom of weld hardly moves. In any cross section of weld, the largest transfer displacement of material appears in the middle of weld. The increase of rotational velocity and the decrease of welding speed are both beneficial to the transfer displacement of material in the middle of weld.

关键词： Friction stir welding 7075-T6 aluminum alloy Thermal-mechanical affected zone Material transfer Numerical simulation

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Multi-place physics and multi-place nonlocal systems

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Communications in Theoretical Physics 2020年第5期72卷 120-132页

作者： s y Lou school of Physical science and Technology Ningbo UniversityNingbo315211China

Multi-place nonlocal systems have attracted attention from many *** this paper,we mainly review the recent progresses on two-place nonlocal systems(Alice-Bob systems)and four-place nonlocal ***-place systems can firstly be derived from many physical problems by using a multiple scaling method with a discrete symmetry group including parity,time reversal,charge conjugates,rotations,field reversal and exchange *** nonlocal systems can also be derived from the symmetry reductions of coupled nonlinear systems via discrete symmetry *** the other hand,to solve multi-place nonlocal systems,one can use the symmetry-antisymmetry separation approach related to a suitable discrete symmetry group,such that the separated systems are coupled local *** using the separation method,all the known powerful methods used in local systems can be applied to nonlocal *** this review article,we take two-place and four-place nonlocal nonlinear schr?dinger(NLs)systems and Kadomtsev-Petviashvili(KP)equations as simple examples to explain how to derive and solve *** types of novel physical and mathematical points related to the nonlocal systems are especially emphasized.

关键词： multi-place physics multi-place nonlocal systems symmetries integrable systems parity and time reversal soliton theory classical prohibitions

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Neumann＇s method for boundary problems of thin elastic shells

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Applied Mathematics and Mechanics(English Edition) 2017年第4期38卷 543-556页

作者： y. s. NEUsTADT Department of Civil Engineering Samara State Architectural and Building University Samara 443001 Russia

The possibility of using Neumann＇s method to solve the boundary problems for thin elastic shells is studied. The variational statement of the static problems for the shells allows for a problem examination within the distribution space. The convergence of Neumann＇s method is proven for the shells with holes when the boundary of the domain is not completely fixed. The numerical implementation of Neumann＇s method normally requires significant time before any reliable results can be achieved. This paper suggests a way to improve the convergence of the process, and allows for parallel computing and evaluation during the calculations.

关键词： boundary problem thin elastic shell theory Neumann's method variational principle Korn's inequality distribution embedding theorem Green tensor

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Effect of Eu^(3+),Bi^(3+),and Li^(+) doping on luminescent property of GdNbO_(4)

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Journal of Rare Earths 2024年第1期42卷 66-75,I0003页

作者： s.W.Wi y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil UniversitySeoul06978Republic of Korea

We investigated the emission properties of Eu^(3+)-doped GdNbO_(4)-based oxide phosphors,aiming at improving the Eu^(3+)emission by codoping of Bi^(3+)and Li^(+).Eu^(3+)singly doped,Eu^(3+)and Bi^(3+)doubly doped,and Eu^(3+),Bi^(3+),and Li^(+)triply doped GdNbO_(4)were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu^(3+)in the singly doped samples are significantly improved by the codoping of Bi^(3+),mainly due to the energy transfer from Bi^(3+)to Eu^(3+).The additional codoping of Li^(+)is found to increase the Eu^(3+)emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu^(3+)in GdNbO_(4)does not change significantly with the codoping of Bi^(3+)and Li^(+).Our results indicate that Li^(+)doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO_(4)phosphors.

关键词： Eu^(3+) GdNbO_(4) Codoping of Li^(+) Photoluminescence sensitizer Rare earths

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Tunneling dynamics of bosons in the diamond lattice chain

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Chinese Physics B 2018年第10期27卷 440-448页

作者： na-na Chang Ju-Kui Xue College of Physics and Electronics Engineering Northwest Normal UniversityLanzhou 730070China

We analyze the effect of tilting and artificial magnetic flux, on the energy bands structure for the system and the corresponding tunneling dynamics for bosons with various initial configurations in the diamond lattice chain, where intriguing and significant phenomena occur, including Landau–Zener tunneling, Bloch oscillations, and localization *** vertical tilting and artificial magnetic flux may alter the structure of energy levels（dispersion structure or flat band）,and enforce the occurrence of Landau–Zener tunneling, which scans the whole of the Bloch bands. We find that, transitions among Landau–Zener tunneling, Bloch oscillations, and localization phenomenon, are not only closely related to the energy bands structure, but also depends on the initial configuration of bosons in the diamond lattice chain. As a consequence,Landau–Zener tunneling, Bloch oscillations, and localization phenonmenon of bosons always counteract and are complementary with each other in the diamond lattice chain.

关键词： Bose-Einstein condensate Landau-Zener tunneling Bloch oscillation localization flat band

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