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A New Optimization Neural Network for High Resolution Time-Frequency Analysis

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电路与系统学报 1997年第1期 1-7页

作者： z.S. Wang,y.S.Xia,J.D.z. Chen,W.H.Li,z.y.he,(Dept. of Radio Engineering, Southeast University, Nanjing, 210096)(Dept. of Mathematics,Nanjing University of Posts & Telecommunications)(Institute for healthcare Researc, Baptist Medical Center, Oklahoma City,

The authors present a new optimization neural network, which can be called as constrained smallest l1-norm neural network (CSl1NN), to implement the Basis Pursuit(BP)[1][2][3]for high resolution time-frequency analysis. As the new and generalized one of the communities of overcomplete signal representations, the BP is considered as a large-scale linear programming problem. In contrast with the Simplex-BP or Interior-BP in [2],the proposed CSl1NN-BP dose not double the optimizing scale and can be implemented in real time through hardware. Taking non-stationary artificial signals and Electrogastrograms (EGGs) to test, our simulations show that the CSl1 NN presents an excellent convergence performance for a wide range of time-frequency(TF)dictionaries and has a higher joint TF resolution not only than the traditional Wigner Distribution (WD), but also than recently rising other overcomplete representation methods, such as Method of Frames (MOF)[9], Best Orthogonal Basis (BOB)[10] and Matching Pursuit (MP)[4]. Combining the high resolution with the fast implementation,the CSl1NN-BP will be very promising for on-line time frequency analysis of various kinds of non-stationary signals,such as linear chirp,qUadric chirp,bumps etc., and medical signals,such as ECG,EEGand EGG,etc., with high quality.

关键词： Neural network Optimization Overcomplete signal representation Basis pursuit Wavelet Time-frequency analysis

Statistical Multi-Fragmentation in Hot Compound Nuclei

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Chinese journal of nuclear physics 1996年第4期 187-199页

作者： G.X.Dai H.y.Wu L.M.Duan z.y.Li Q.z.Luo z.y.he B.G.zhang W.X.Wen Institute of Modern Physics,the Chinese Academy of Scienoes,P.O.Bax 31,Lanzhou 730000

The first three-fold and four-fold fragmentation measurements in hot compound nuclei pro-duced in the reactions of a 25 MeV/u 40At beam with targets of 209Bi,197Au,159Tb,115In,103Rh,and93Nb are *** distributions are measured for these fragments,including distributions of ve-locities,relative velocities,angles,relative angles,masses,fragment mass ratios,total kinetic energies（TKE）,as well as the yield ratios of three-fold fragmentation to fission P32 and the time difference △t be-tween two scissions after the formation of one compound nucleus.

关键词： —Three-fold and four-fold fragmentation Scission time difference yield ratio P32 Biaxial deformation Triaxial deformation Space-time model

Advances in the treatment of autism spectrum disorder:Wharton jelly mesenchymal stem cell transplantation

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World Journal of Methodology 2025年第1期15卷 72-79页

作者： Serdar Kabatas ErdinçCivelek Eyüp Can Savrunlu Umut Karaaslan Özlem yıldız Erdal Karaöz Department of Neurosurgery University of Health Sciences TurkeyGaziosmanpaşa Training and Research HospitalIstanbul 34255Türkiye Department of Pediatric Allergy-Immunology Institute of Health Sciences Marmara UniversityIstanbul 34865Türkiye Center for Stem Cell&Gene Therapy Research and Practice University of Health Sciences TurkeyIstanbul 34255Türkiye Department of Child and Adolescent Psychiatry University of Health SciencesGaziosmanpaşa Training and Research HospitalIstanbul 34255Türkiye Department of Child and Adolescent Psychiatry Kocaeli University Faculty of MedicineKocaeli 41001Türkiye Center for Regenerative Medicine and Stem Cell Research&Manufacturing Liv HospitalIstanbul 34340Türkiye Department of Histology and Embryology Istinye UniversityFaculty of MedicineIstanbul 34010Türkiye Center for Stem Cell and Tissue Engineering Research and Practice Istinye UniversityIstanbul 34340Türkiye

BACKGROUND Autism spectrum disorder(ASD)is a complex neurodevelopmental disorder with multifaceted *** recent studies,neuroinflammation and immune dysregulation have come to the forefront in its *** are studies suggesting that stem cell therapy may be effective in the treatment of *** To evolve the landscape of ASD treatment,focusing on the potential benefits and safety of stem cell *** A detailed case report is presented,displaying the positive outcomes observed in a child who underwent intrathecal and intravenous Wharton’s jelly-derived mesenchymal stem cells(WJ-MSCs)transplantation combined with *** The study demonstrates a significant improvement in the child’s functional outcomes(Childhood Autism Rating Scale,Denver 2 Developmental Screening Test),especially in language and gross motor *** serious side effects were encountered during the 2-year *** The findings support the safety and effectiveness of WJ-MSC transplantation in managing ASD.

关键词： Autism spectrum disorder Neurorehabilitation Stem cell transplantation Wharton jelly mesenchymal stem cells Inflammation

Dislocation ordering and texture strengthening of naturally aged Al-Cu-Mg alloy

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Journal of Materials Science & Technology 2022年第23期118卷 1-14页

作者： F.Liu z.y.Liu G.y.he L.N.Ou School of Materials Science and Engineering Central South UniversityChangsha 410083China Key Laboratory of Nonferrous Metal Materials Science and Engineering Ministry of EducationCentral South UniversityChangsha 410083China National Key Laboratory of Science and Technology on High-Strength Structural Materials Central South UniversityChangsha 410083China

Stability of grain structure,dislocation ordering and strengthening mechanisms of the naturally aged AlCu-Mg alloy after solution treatment are investigated by using optical microscope(OM),scanning electron microscope(SEM),electron back-scattered diffraction(EBSD),X-ray diffraction(XRD) and transmission electron microscope(TEM).Results show that {100},{100},{110} and {110}slip systems can be activated after solution treatment,which can promote the formation of {110}Goss *** combination effect of T-Al_(20)Cu_(2) Mn_(3) phase and Goss-oriented grains with large Taylor factor makes the solution-treated alloys display excellent stability of grain *** enhanced yield strength of the alloy is ascribed to grain-refine strengthening,dispersed particles strengthening,dislocation strengthening and texture *** coarsening of the second phase is responsible for softening of the alloy after annealing at 400 ℃+solution treatment at 475 ℃.

关键词： Al-Cu-Mg alloy Dislocation ordering Goss texture Grain structure stability Texture strengthening

Test Study on the Recycled Aggregate and Concrete Regenerated from Worn Cement Concrete Pavement

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武汉理工大学学报 2010年第17期32卷 241-245页

作者： DONG y he W z Faculty of Architecture and Civil Engineering of Huaiyin Institute of Technology Huaiyin 223001China

Regenerate utilization of worn cement concrete is the key technical problem to be solved in traffic field while the cement concrete pavement built long ago durative disrepair. The study aimed at the worn cement concrete which can not be reused in site,get recycled aggregate according to the practically technics of regenerate,and then carry out test study on the aggregate and recycle aggregate cement concrete. Test results show recycled fine aggregate is about 26% of recycled aggregate,and substantive sand pulps are adhere on the surface of recycled while the distinct crackle appears on this sand pulp surface. relative to the natural aggregate,one of the remarkable characters of the recycled aggregate is that the inartificial water ratio is relatively low and the water-absorbing ratio can reach 4%～12%,and the water-absorbing ratio increased while the grain getting fine. the second remarkable characters of recycled coarse aggregate is that the weared stone value and crushed stone value of recycled coarse aggregate are both bigger,the Los-angeles weared stone value is 32.7,the crushed stone value is 26.5. So,the recycled aggregate can not meet the criterion,but after mixed into 40% natural aggregate,it can meet. The mixture ratio test results proved that based on the dosage of cement we can through reduce water cement ratio and augment water quantity to improve the working performance of recycled concrete. The destroy form of recycled concrete goes all the way with natural concrete,the recycled aggregate can absolutely used in cement concrete under C50.

关键词： cement concrete pavement recycled aggregate gradation weared stone value crushed stone value water cement ratio

Magnetic and Electrical Behavior of MnTe_(1-x)Sb_x Alloys

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Journal of Materials Science & Technology 2011年第1期27卷 64-68页

作者： X.he y.Q.zhang z.D.zhang Shenyang National Laboratory for Materials Science Institute of Metal Researchand International Center for Materials PhysicsChinese Academy of SciencesShenyang 110016China

The structure,specific heat,magnetic and electrical properties of MnTe1-xSbx（x=0,0.1,0.15,0.2 and 0.25） alloys have been *** MnTe1-xSbx alloys crystallize in a hexagonal NiAs-type structure,and the impurity of MnSb phase appears when x≥*** MnTe0.9Sb0.1 compound exhibits ferrimagnetic behavior with hysteresis loops even at 350 K,showing that the magnetic properties of MnTe compound are very sensitive to little compositional *** ferromagnetism in the MnTe1-xSbx alloys with higher Sb contents may be attributed to the impurity of MnSb *** dispersive X-ray spectroscopy analysis on the MnTe0.9Sb0.1 compound indicates that Sb is very difficult to dope into the lattice of *** the anomaly of resistivity at 300 K of MnTe0.9Sb0.1 and the peak of specific heat around 304 K of all the alloys are thought to be related with the antiferromagnetic interactions of MnTe-based lattice.

关键词： Electronic transport property Hysteresis loop Specific heat

Correlation between depassivation and repassivation processes determined by single particle impingement:Its crucial role in the phenomenon of critical flow velocity for erosion-corrosion

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Journal of Materials Science & Technology 2021年第30期89卷 158-166页

作者： L.L.Li z.B.Wang S.y.he y.G.zheng CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Department of Physics Southern University of Science and TechnologyGuangdong 518055China

The correlation between depassivation and repassivation processes,which is significant in erosioncorrosion,was quantitatively investigated by single particle impingement tests at various flow velocities and impact *** results show that both repassivation and depassivation processes are associated with the kinetic energy of solid particle,and demonstrate that the repassivation is retarded by *** phenomenon probably results from the depassivation-induced microstructure *** this basis,the dependence of critical flow velocity(CFV)for erosion-corrosion on the solid particle concentration and diameter is further theoretically predicted and experimentally ***,the crucial role of depassivation-repassivation in CFV phenomenon is further highlighted.

关键词： Erosion-corrosion Stainless steel Depassivation-repassivation Single particle impact Passive film

Structure and Magnetic Properties of S-doped Mn_3O_4/S Composited Nanoparticles and Mn_3O_4 Nanoparticles

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Journal of Materials Science & Technology 2011年第6期27卷 503-506页

作者： X. he z.H. Wang D.y. Geng z.D. zhang Shenyang National Laboratory for Materials Science Institute of Metal Research and International Centre for Materials Physics Chinese Academy of Sciences Shenyang 110016 China

Composited nanoparticles,consisting of Mn3O4,S-doped Mn3O4 and S,were synthesized by co-precipitation reaction and Mn3O4 nanoparticles were then obtained after removing the pure S from the composited *** Mn3O4-type phase with larger lattice constant a was formed by doping *** fixed temperatures below Curie temperature（TC）,the magnetization of the S-doped Mn3O4/S composited nanoparticles was smaller than that of the Mn3O4 *** blocking temperature was 36.3 and 34.8 K for Sdoped Mn3O4/S composite and Mn3O4 nanoparticles,*** anisotropy field of S-doped Mn3O4/S composite was determined to be about 55.3 kOe.

关键词： Nanostructured materials Chemical synthesis X-ray diffraction Magnetic measurements

Distinct Electrical and Mechanical Responses of a Cu-10Fe Composite Prepared by Hot-Pressed Sintering and Post Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 255-265页

作者： X.y.yue S.y.Peng X.zhang C.N.he y.z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin300350China Research Centre for Metallic Wires Northeastern UniversityShenyang110819China

A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the Cu-10wt%Fe *** Cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IACS and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance Cu-based in-situ composites by post treatment.

关键词： Cu-Fe composite Hot-pressed sintering Thermal stability Strength Electrical conductivity