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Nuclear Science and Techniques 2018年第10期29卷 221-228页

作者： m.r.pahlavani P.mehdipour Department of Physics Faculty of Basic Science University of Mazandaran

Photofission fragments mass yield for^(232)Th,^(234;238) U,^(237) Np, and^(239;240;242) Pu isotopes are *** calculations are done using a developed approach based on Gorodisskiy's phenomenological formalism. The Gorodisskiy's method is developed to be applied for the neutron-induced fission. Here we revised it for application to photofission. The effect of emitted neutron prior to fission on the fission fragment mass yields has also been studied. The peak-to-valley ratio is extracted for the240 Pu isotope as a function of energy. Obtained results of the present formalism are compared with the available experimental data. Satisfactory agreement is achieved between the results of present approach and the experimental data.

关键词： Fission fragments Fragment mass yield Photofission Neutron fission Heavy nuclei Peak-to-valley

Tin-accompanied and true ternary fission of 242Pu

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Chinese Physics C 2019年第9期43卷 46-54页

作者： m.Zadehrafi m.r.pahlavani m.-r.Ioan Department of Physics Faculty of Basic ScienceUniversity of MazandaranP.O.Box 47415-416BabolsarIran Horia Hulubei National Institute for Physics and Nuclear Engineering(IFIN-HH) P.O.Box MG-6RO-077125Bucharest-MagureleRomania

True ternary fission and Tin-accompanied ternary fission of 242Pu are studied by using the'Three Cluster model'.True ternary fission is considered as a formation of heavy fragments in the region 28≤Z1,Z2,Z3≤38 with comparable *** possible fission channels are predicted by the potential-energy *** potentials,Q-values and relative yields for all possible fragmentations in equatorial and collinear configurations are calculated and *** is found that ternary fission with formation of a double magic nucleus like 132Sn is more probable than the other ***,the kinetic energies of the fragments for the group Z1=32,Z2=32 and Z3=30 are calculated for all combinations in the collinear geometry as a sequential decay.

关键词： true ternary fission three cluster model equatorial collinear kinetic energy

Solutions of Woods-Saxon Potential with Spin-Orbit and Centrifugal Terms through Nikiforov-Uvarov method

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Communications in Theoretical Physics 2012年第11期58卷 739-743页

作者： m.r. pahlavani S.A. Alavi Department of Nuclear Physics Faculty of SciencesMazandaran University

In this study, the analytical solutions of the radial Schr6dinger equation for the central Woods-Saxon potential together with spin-orbit interaction and centrifugal terms have been derived by using Nikiforov-Uvarov method. The energy eigenvalues and corresponding eigenfunctions of nucleons have been obtained for various values of n, l, and j quantum numbers. The obtained results using this method are in satisfactory agreement with available data in the specim case.

关键词： chrSdinger equation spin-orbit interaction Woods-Saxon potential Nikiforov-Uvarov method

Effects of Isotopic Concentrations on Thermodynamic Parameters of Deuterium-Tritium mixtures

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Communications in Theoretical Physics 2013年第7期60卷 108-112页

作者： S.m. motevalli m.r. pahlavani m. Azimi Department of Nuclear Physics Faculty of Science University of Mazandaran

Thermodynamic estimation is still too much requested for scientific applications in spite of great advances in simulation methods for efficient determination of phase equilibrium of multi-component systems. In this work, thermodynamic properties of deuterium-tritium mixture in a wide range of temperatures and pressures have been predicted. Buckingham exp-6 potential has been utilized in calculations, based on statistical perturbation theory. The effects of various values of density, temperature and isotopic concentrations on pressure have been studied. Eventually, we have found out symmetrical effects of tritium concentration in deuterium-tritium mixtures.

关键词： Deuterium-tritium mixture thermodynamic property buckingham exp-6 potential Tritium concentration

Heterogeneity of mature oligodendrocytes in the central nervous system

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Neural regeneration research 2025年第5期20卷 1336-1349页

作者： Chao Weng Adam m.r.Groh moein Yaqubi Qiao-Ling Cui Jo Anne Stratton G.r.Wayne moore Jack P.Antel Neuroimmunology Unit Montreal Neurological Institute-HospitalDepartment of Neurology and NeurosurgeryMcGill UniversityMontrealQCCanada Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous *** evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is *** delve into early 20th-century studies by robertson and río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature ***,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination ***,modern molecular investigations,employing techniques such as single cell/nucleus rNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system *** and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined *** studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte *** research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,

关键词： aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history neuroglia oligodendroglia single-cell gene expression analysis

Dynamic rupture and crushing of an extruded tube using artificial neural network(ANN)approximation method

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Journal of Central South University 2016年第4期23卷 869-879页

作者： Javad marzbanrad Behrooz mashadi Amir Afkar mostafa pahlavani School of Automotive Engineering Iran University of Science and TechnologTehranIran Faculty of Electrical Mechanical and Construction EngineeringDepartment of Automotive EngineeringStandard Research Institute(SRI)Karaj P.O.Box 31745-139Iran

A numerical study of the crushing of thin-walled circular aluminum tubes has been carried out to investigate the crashworthiness behaviors under axial impact loading. These kinds of tubes are usually used in automobile and train structures to absorb the impact energy. Previous researches show that thin-walled circular tube has the highest energy absorption under axial impact amongst different structures. In this work, the crushing between two rigid flat plates and the tube rupture by 4 and 6 blades cutting tools is modeled with the help of ductile failure criterion using the numerical method. The tube material is aluminum EN AW-7108 T6 and its length and diameter are 300 mm and 50 ram, respectively. Using the artificial neural network （ANN）, the most important surfaces of energy absorption parameters, including the maximum displacement of the striker, the maximum axial force, the specific energy absorption and the crushing force efficiency in terms of impact velocity and tube thickness are obtained and compared to each other. The analyses show that the tube rupture by the 6 blades cutting tool has more energy absorption in comparison with others. Furthermore, the results demonstrate that tube cutting with the help of multi-blades cutting tools is more stable, controllable and predictable than tube folding.

关键词： thin-walled structure rupture energy absorption ductile failure criterion neural network

Emission angle dependence of average fission fragments spin using combined dynamical and statistical approach

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Emission angle dependence of average fission fragments spin ...

Getting physical with medical education:Exercise based virtual anatomy review classes for medical students

The 10~th International Conference on Nucleus-Nucleus Collisions

作者： m.r.pahlavani Department of Physics Faculty of Basic SciencesUniversity of MazandaranPOBox 47416-1467BabolsarIRAN

In this work the combination of multi dimensional Langvin equation(L.E) and Transition State model(TSm) have been applied to investigate the total fragment spin of systems O + Bi and O +*** influence of asymmetry para...

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World Journal of methodology 2025年第1期15卷 20-25页

作者： Nadeesha r Samarasinghe Taniya S Nagpal michele L Barbeau Charys m martin Division of General Surgery Faculty of MedicineUniversity of British ColumbiaVancouver V6T 1Z3BCCanada Faculty of Kinesiology Sport and RecreationUniversity of AlbertaEdmonton T6G 2R3ABCanada Anatomy and Cell Biology University of Western OntarioLondon N6A 3K7ONCanada Department of Anatomy and Cell Biology Schulich School of Medicine and DentistryThe University of Western OntarioLondon N6A 3K7ONCanada

The benefits of regular physical activity are well ***,few studies have examined the effectiveness of integrating physical activity(PA)into curricula within a post-secondary *** investigate the incorporation of PA into medical curriculum,we developed a series of optional exercise-based review sessions designed to reinforce musculoskeletal(mSK)anatomy course *** synchronous sessions were co-taught by a group fitness instructor and an anatomy *** fitness instructor would lead students through both strength and yoga style exercises,while the anatomy instructor asked questions about relevant anatomical structures related to course material previously *** the sessions,participants were asked to evaluate the classes on their self-reported exam preparedness in improving mSK anatomy knowledge,PA levels,and mental *** participants completed surveys;a majority agreed that the classes increased understanding of mSK concepts(90.0%)and activity levels(97.7%).many(70.0%)felt that the classes helped reduce *** majority of respondents(90.0%)agreed that the classes contributed to increased feelings of social ***,medical students saw benefit in PA based interventions to supplement mSK course *** with increasing activity levels and promoting health behaviours,integrating PA into medical curriculum may improve comprehension of learning material,alleviate stress and foster social connectivity among medical students.

关键词： medical education musculoskeletal Anatomy Exercise Online learning

machine Learning Techniques in Predicting Hot Deformation Behavior of metallic materials

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Computer modeling in Engineering & Sciences 2025年第1期142卷 713-732页

作者： Petr Opela Josef Walek Jaromír Kopecek Department of metallurgical Technologies Faculty of Materials Science and TechnologyVSB–Technical University of OstravaOstrava70800Czech Republic FZU—Institute of Physics of the Czech Academy of Sciences Prague18200Czech Republic

In engineering practice,it is often necessary to determine functional relationships between dependent and independent *** relationships can be highly nonlinear,and classical regression approaches cannot always provide sufficiently reliable ***,machine Learning(mL)techniques,which offer advanced regression tools to address complicated engineering issues,have been developed and widely *** study investigates the selected mL techniques to evaluate their suitability for application in the hot deformation behavior of metallic *** mL-based regression methods of Artificial Neural Networks(ANNs),Support Vector machine(SVm),Decision Tree regression(DTr),and Gaussian Process regression(GPr)are applied to mathematically describe hot flow stress curve datasets acquired experimentally for a medium-carbon *** the GPr method has not been used for such a regression task before,the results showed that its performance is the most favorable and practically unrivaled;neither the ANN method nor the other studied mL techniques provide such precise results of the solved regression analysis.

关键词： machine learning Gaussian process regression artificial neural networks support vector machine hot deformation behavior

A mutual information-Dempster-Shafer based decision ensemble system for land cover classification of hyperspectral data

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Frontiers of Structural and Civil Engineering 2017年第4期11卷 774-783页

作者： Parham pahlavani Behnaz BIGDELI Center of Excellence in Geomatics Engineering in Disaster management School of Surveying and Geospatial Engineering College of Engineering University of Tehran Tehran *** Iran

Hyperspectral images contain extremely rich spectral information that offer great potential to discrimi- nate between various land cover classes. However, these images are usually composed of tens or hundreds of spectrally close bands, which result in high redundancy and great amount of computation time in hyperspectral classification. Furthermore, in the presence of mixed coverage pixels, crisp classifiers produced errors, omission and commission. This paper presents a mutual informa- tion-Dempster-Shafer system through an ensemble classi- fication approach for classification of hyperspectral data. First, mutual information is applied to split data into a few independent partitions to Then, a fuzzy maximum overcome high dimensionality. likelihood classifies each band subset. Finally, Dempster-Shafer is applied to fuse the results of the fuzzy classifiers. In order to assess the proposed method, a crisp ensemble system based on a support vector machine as the crisp classifier and weighted majority voting as the crisp fusion method are applied on hyperspectral data. Furthermore, a dimension reduction system is utilized to assess the effectiveness of mutual information band splitting of the proposed method. The proposed methodology provides interesting conclusions on the effectiveness and potentiality of mutual information- Dempster-Shafer based classification ofhyperspectral data.

关键词： mutual information Dempster-Shafer hyper- spectral classification support vector machine