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Chinese Journal of electrical engineering 2024年第1期10卷 1-2页

作者： Li J. Mei h. Li s. Tianjin University China Tsinghua shenzhen International Graduate school China Lanzhou Jiaotong University China

The rapid development of clean and renewable energy technologies represented by wind and solar energy,as well as the continuous growth of load demand,have put forward higher requirements for the safe operation of the power *** performance of power equipment based on traditional dielectric materials is often limited by various defects generated during molding,transportation,assembly,and operation,which cannot meet the reliability requirements of power systems in the new *** detection is an essential technical method in industrial development,which can detect and evaluate the defect and damage status of in-service equipment,key components,and materials without damaging the object.

关键词： service Application operation

Machine learning-based predictions of current and future susceptibility to retrogressive thaw slumps across the Northern hemisphere

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Advances in Climate Change Research 2024年第2期15卷 253-264页

作者： Jing LUO Guo-An YIN Fu-Jun NIU Tian-Chun DONG ze-Yong GAO Ming-hao LIU Fan YU state Key Laboratory of Frozen soil engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway Qinghai-Tibet Group Co. LtdXining 810000China University of Chinese Academy of sciences Beijing 100049China

Retrogressive thaw slumps(RTss)caused by the thawing of ground ice on permafrost slopes have dramatically increased and become a common permafrost hazard across the Northern hemisphere during previous ***,a gap remains in our comprehensive understanding of the spatial controlling factors,including the climate and terrain,that are conducive to these RTss at a global *** machine learning methodologies,we mapped the current and future RTss susceptibility distributions by incorporating a range of environmental factors and RTss *** identified freezing-degree days and maximum summer rainfall as the primary environmental factors affecting RTss *** final ensemble susceptibility map suggests that regions with high to very high susceptibility could constitute(11.6±0.78)%of the Northern hemisphere's permafrost *** juxtaposed with the current(2000-2020)RTss susceptibility map,the total area with high to very high susceptibility could witness an increase ranging from(31.7±0.65)%(ssP585)to(51.9±0.73)%(ssP126)by the *** insights gleaned from this study not only offer valuable implications for engineering applications across the Northern hemisphere,but also provide a long-term insight into the potential change of RTss in permafrost regions in response to climate change.

关键词： Retrogressive thaw slump Machine learning susceptibility map Permafrost Northern hemisphere

superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： h.T.Jeong s.W.Lee W.J.Kim Department of Materials science and engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the hCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy superplasticity severe plastic deformation Grain size Grain growth

All-electron basis sets for h to Xe specific for ZORA calculations:Applications in atoms and molecules

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Chinese Physics B 2024年第8期33卷 238-246页

作者： C.s.Gomes F.e.Jorge A.Canal Neto Departamento de Fisica Universidade Federal do Espirito Santo29075-910 VitoriaESBrazil Departamento de Fisica Instituto de Ciencias Exatas e BiologicasUniversidade Federal de Ouro Preto Campus Universitario Morro do Cruzeiro35402-136 Ouro PretoMGBrazil

A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for h through Xe was developed to be used in conjunction with the ZORA *** set was augmented with diffuse functions to describe electrons farther away from the nuclei *** the ZORA-CCsD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,and atomization energies of some molecules were *** addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular *** atomization energies,a similar observation emerges when considering spin-orbit *** the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental *** evaluations of the ZORA and Douglas–Kroll–hess hamiltonians were made for each property studied.

关键词： QZP-ZORA and AQZP-ZORA basis sets elements from h to Xe CCsD(T)method atomic and molecular properties

Controlling the si/C ratio in siC matrix based on the modified polymethysilane for C/C-siC composites with enhanced mechanical properties

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Journal of Advanced Ceramics 2024年第2期13卷 220-236页

作者： Mingdong Liao Xiebo hu Chenghao Zhong Ping Xu Xiaodong Wang ze Zhang Peng Zhou Mingyu Zhang Zhean su Qizhong huang National Key Laboratory of science and Technology on high-strength structural Materials Central South UniversityChangsha 410083China

Fabricating siC matrix with controllable si/C ratio for C/C-siC composites via precursor infiltration and pyrolysis is difficult to realize due to the absence of suitable ***,siC precursors with si-rich(si/C=1.23),nearstoichiometric(si/C=1.01),and C-rich(si/C=0.88)pyrolyzed ceramics at 1200℃ were successfully synthesized by the novel modification of *** structure and ceramization of synthesized siC precursors were studied,and C/C-siC composites with similar si/C ratio in siC matrix were also *** results revealed that the defects and Young’s modulus of siC matrix and the thermal residual stress on pyrolytic carbon coated carbon fiber were determined by the si/C *** a result,the si/C ratio exerted significant effects on the crack deflection behavior and the mechanical properties of the *** composites with near-stoichiometric siC matrix showed excellent mechanical properties because of the effective crack deflection and the moderate Young’s modulus of their siC *** flexural strength,flexural modulus,and compressive strength were 423±27 MPa,33.41±4.52 GPa,and 393±8 MPa,***,after a heat treatment at 1600℃,the role of carbon fiber toughening was improved and accompanied by a decrease in mechanical properties for all composites,which was attributed to the increased defects in siC matrix and the damaged interfaces by the thermal residual stress.

关键词： siC precursor si/C ratio polymethysilane C/C–siC composites mechanical properties

Multiple scales method for analyzing a forced damped rotational pendulum oscillatorwithgallows

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Communications in Theoretical Physics 2024年第5期76卷 58-67页

作者： haifa A Alyousef Alvaro h salas B M Alotaibi s A el-Tantawy Department of Physics College of SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Department of Mathematics and statistics Universidad Nacional de ColombiaFIZMAKO Research GroupColombia Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt Research Center for Physics(RCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversityAl-Baha 1988Saudi Arabia

This study reports the analytical solution for a generalized rotational pendulum system with gallows and periodic excited *** multiple scales method(MsM)is applied to solve the proposed *** types of rotational pendulum oscillators are studied and talked about in *** include the forced damped rotating pendulum oscillator with gallows,the damped standard simple pendulum oscillator,and the damped rotating pendulum oscillator without *** MsM first-order approximations for all the cases mentioned are derived in *** obtained results are illustrated with concrete numerical *** first-order MsM approximations are compared to the fourth-order Runge-Kutta(RK4)numerical ***,the maximum error is estimated for the first-order approximations obtained through the MsM,compared to the numerical approximations obtained by the RK4 ***,we conducted a comparative analysis of the outcomes obtained by the used method(MsM)and he-MsM to ascertain their respective levels of *** proposed method can be applied to analyze many strong nonlinear oscillatory equations.

关键词： rotational pendulum system multiple scales method approximate solution damped oscillations forced pendulum with gallows he-multiple scales method

Mast cell activation syndrome:An up-to-date review of literature

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World Journal of Clinical Pediatrics 2024年第2期13卷 104-113页

作者： ÖnerÖzdemir Gökçe Kasımoğlu Ayşegül Bak hüseyin sütlüoğlu süreyya savaşan Department of Pediatric Allergy and Immunology Sakarya UniversitySakaryaAdapazarı54100Türkiye Department of Pediatrics Sakarya UniversitySakaryaAdapazarı54100Türkiye Department of Pediatrics Kocaeli City HospitalKocaeli 50123Türkiye Department of Pediatrics Children’s Hospital of MichiganHematology/OncologyCentral Michigan University College of MedicineMount PleasantMI 48859United States Barbara Ann Karmanos Cancer Institute Wayne State UniversityDetroitMI 12345United States

Mast cells are a subtype of white blood cells and are involved in the immune *** cells contain many chemical substances called mediators,which are involved in the allergic *** fact that mast cells play a role in many events that require urgent intervention,especially anaphylaxis,has led to a more detailed study of these *** diseases also caused by dysfunctions of mast cells have been examined in many *** instance,mast cell activation syndrome is known as an augmented number of cells due to decreased cell death,resulting in clinical symptoms affecting many *** main common symptoms include flushing,hypotension,urticaria,angioedema,headache,vomiting and *** the underlying mechanism is not yet clearly known,we aim to review the literature in a broad perspective and bring together the existing knowledge in the light of the literature due to the diversity of its involvement in the body and the fact that it is a little known syndrome.

关键词： Mast cell Mast cell activation syndrome Tryptase histamine

A hybrid machine-learning model for solar irradiance forecasting

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Clean energy 2024年第1期8卷 100-110页

作者： Ameera M.Almarzooqi Maher Maalouf Tarek h.M.el-Fouly Vasileios e.Katzourakis Mohamed s.el Moursi Constantinos V.Chrysikopoulos Department of Industrial and systems engineering Khalifa UniversityAbu DhabiPO Box 127788UAE electrical engineering and Computer science Department Khalifa University Abu DhabiUAE Department of Civil Infrastructure and environmental engineering Khalifa UniversityAbu DhabiPO Box 127788UAE school of Chemical and environmental engineering Technical University of CreteChaniaGreece

Nowcasting and forecasting solar irradiance are vital for the optimal prediction of grid-connected solar photovoltaic(PV)power *** plants face operational challenges and scheduling dispatch difficulties due to the fluctuating nature of their power *** the generation capacity within the electric grid increases,accurately predicting this output becomes increasingly essential,especially given the random and non-linear characteristics of solar irradiance under variable weather *** study presents a novel prediction method for solar irradiance,which is directly in correlation with PV power output,targeting both short-term and medium-term forecast *** proposed hybrid framework employs a fast trainable statistical learning technique based on the truncated-regularized kernel ridge regression *** proposed method excels in forecasting solar irradiance,especially during highly intermittent weather periods.A key strength of our model is the incorporation of multiple historical weather parameters as inputs to generate accurate predictions of future solar irradiance values in its scalable *** evaluated the performance of our model using data sets from both cloudy and sunny days in seattle and Medford,UsA and compared it against three forecasting models:persistence,modified 24-hour persistence and least *** on three widely accepted statistical performance metrics(root mean squared error,mean absolute error and coefficient of determination),our hybrid model demonstrated superior predictive accuracy in varying weather conditions and forecast horizons.

关键词： solar power generation kernel ridge regression hybrid model forecasting

Music as medicine for traumatic brain injury:a perspective on future research directions

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Neural Regeneration Research 2024年第10期19卷 2105-2106页

作者： Anthony e.Kline eleni h.Moschonas Corina O.Bondi Department of Physical Medicine&Rehabilitation University of PittsburghPittsburghPAUSA safar Center for Resuscitation Research University of PittsburghPittsburghPAUSA Center for Neuroscience University of PittsburghPittsburghPAUSA Department of Critical Care Medicine University of PittsburghPittsburghPAUSA Center for the Neural Basis of Cognition University of PittsburghPittsburghPAUSA Department of Psychology University of PittsburghPittsburghPAUSA Department of Neurobiology University of PittsburghPittsburghPAUSA

Traumatic brain injury(TBI) impacts 69 million individuals globally each year and is a leading cause of death and disability(Dewan et al.,2019).The majority of moderate-to-severe TBI survivors endure long-lasting disturbances in motor,cognitive,and affect that negatively impacts their *** a plethora of research on pharmacological interventions for TBI has been conducted,none has translated to the clinic,thus advocating for the evaluation of nonpharmacological therapeutic approaches that may increase translational success.

关键词： injury traumatic

Research on Pulsar Time steered Atomic Time Algorithm Based on DPLL

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Research in Astronomy and Astrophysics 2024年第3期24卷 237-248页

作者： ze.hao Zheng Yang Liu Dan shen Fan Feng Jiu-Long Liu Yue-Xin Ma Xiang-Wei Zhu school of electronic and Communication engineering Sun Yat-sen UniversityShenzhen 518107China school of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China school of systems science and engineering Sun Yat-sen UniversityGuangzhou 510275China

In today’s society,there is a wide demand for high-precision and high-stability time service in the fields of electric power,communication,transportation and *** present,the time standard in various countries is mainly based on atomic clocks,but the frequency drift of atomic clocks will affect the long-term stability *** with atomic clocks,millisecond pulsars have better long-term stability and can complement with the excellent short-term stability of atomic *** order to improve the long-term stability of the atomic timescale,and then improve the timing accuracy,this paper proposes an algorithm for steering the atomic clock ensemble(ACe)by ensemble pulsar time(ePT)based on digital phase locked loop(DPLL).First,the ACe and ePT are generated by the ALGOs algorithm,then the ACe is steered by ePT based on DPLL to calibrate the long-term frequency drift of the atomic clock,so that the generated steered atomic time follows both the short-term stability characteristics of ACe and the long-term stability characteristics of ePT,and finally,the steered atomic time is used to calibrate the local cesium *** experimental results show that the long-term stability of atomic time after steering is improved by 2 orders of magnitude compared with that before steering,and the daily drift of a local cesium clock after calibration is less than 9.47 ns in 3 yr,3 orders of magnitude higher than that before calibration on accuracy.

关键词： (stars) pulsars general-time-methods data analysis-instabilities