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Traveling Wave Characteristics Based Pilot Protection scheme for Hybrid Cascaded HVDC Transmission line

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Journal of Modern Power systems and Clean Energy 2024年第3期12卷 971-980页

作者： Dalin Mu sheng lin Xiaopeng Li the school of Electrical Engineering Southwest Jiaotong UniversityChengdu 611756China the state Grid sichuan Electric Power Research Institute Chengdu 610041China

The hybrid cascaded high-voltage direct current(HVDC)transmission system has various operation modes,and some operation modes have sharply increasing requirements for protection rapidity,while the traditional pilot differential protection(PDP)has poor rapidity,and even refuses to operate when faults occur on the DC ***,a novel pilot protection scheme based on traveling wave characteristics is ***,the adaptability of the traditional PDP applied in engineering is analyzed for different operation ***,the expressions of the forward traveling wave(fTW)and backward traveling wave(BTW)on the rectifier side and the inverter side are derived for different fault *** the theoretical derivation,the difference between the BTW and fTW on the rectifier side is less than zero,and the same is true on the inverter ***,in the event of an external fault of DC line,the difference between the BTW and fTW at nearfault terminal protection installation point is greater than ***,by summing over the product of the difference between BTW and fTW of the rectifier side and that of the inverter side,the fault identification criterion is *** simulation results show that the proposed pilot protection scheme can quickly and reliably identify the short-circuit faults of DC line in different operation modes.

关键词： Hybrid cascaded high-voltage direct current(HVDC)transmission system DC line operation mode pilot protection

study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-lin shen Jian-Jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the shanghai Laser Electron Gamma source facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

An Improved Method for Approximating the Infinite-Horizon Value function of the Discrete-Time switched LQR Problem

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Journal of systems science & Complexity 2024年第1期37卷 22-39页

作者： HOU Tan LI Yuanlong lin Zongli Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of system Control and Information Processing Ministry of Education of ChinaShanghai 200240China shanghai Engineering Research Center of Intelligent Control and Management Shanghai 200240China Charles L.Brown Department of Electrical and Computer Engineering University of VirginiaCharlottesvilleVA 22904-4743USA

This paper considers the problem of approximating the infinite-horizon value function of the discrete-time switched LQR *** particular,the authors propose a new value iteration method to generate a sequence of monotonically decreasing functions that converges exponentially to the value *** method facilitates us to use coarse approximations resulting from faster but less accurate algorithms for further value iteration,and thus,the proposed approach is capable of achieving a better approximation for a given computation time compared with the existing *** numerical examples are presented in this paper to illustrate the effectiveness of the proposed method.

关键词： Optimal control switched linear systems switched LQR problem.

A new elastoplastic model for bolt-grouted fractured rock

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International Journal of Mining science and Technology 2024年第7期34卷 995-1016页

作者： Haoyi Li shuangying Zuo Peiyuan lin state Key Laboratory for Tunnel Engineering Sun Yat-Sen UniversityGuangzhou 510275China southern Marine science and Engineering Guangdong Laboratory Zhuhai 519082China school of Civil Engineering Sun Yat-Sen UniversityGuangzhou 510275China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China

Complexities in mechanical behaviours of rock masses mainly stem from inherent discontinuities,which calls for advanced bolt-grouting techniques for stability *** the mechanical properties of bolt-grouted fractured rock mass(BGfR)and developing accurate prediction methods are crucial to optimize the BGfR support *** paper establishes a new elastoplastic(E-P)model based on the orthotropic and the Mohr-Coulomb(M-C)plastic-yielding *** elastic parameters of the model were derived through a meso-mechanical analysis of composite materials mechanics(CMM).Laboratory BGfR specimens were prepared and uniaxial compression test and variable-angle shear test considering different bolt arrangements were carried out to obtain the mechanical parameters of the *** showed that the anisotropy of BGfR mainly depends on the relative volume content of each component material in a certain ***,the mechanical parameters deduced from the theory of composite materials which consider the short fibre effect are shown to be in good agreement with those determined by laboratory experiments,and the variation rules maintained good ***,a case study of a real tunnel project is provided to highlight the effectiveness,validity and robustness of the developed E-P model in prediction of stresses and deformations.

关键词： Bolt-grouted fractured rock mass Elastoplastic model Composite materials mechanics Laboratory experiment

flexible Crystal Heterojunctions of Low-Dimensional Organic Metal Halides Enabling Color-Tunable space-Resolved Optical Waveguides

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Research 2024年第3期6卷 293-304页

作者： Yuhang lin shuya Liu Dongpeng Yan Beijing Key Laboratory of Energy Conversion and storage Materials and Key Laboratory of RadiopharmaceuticalsMinistry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China.

Molecular luminescent materials with optical waveguide have wide application prospects in light-emitting diodes, sensors, and logic gates. However, the majority of traditional optical waveguide systems are based on brittle molecular crystals, which limited the fabrication, transportation, storage, and adaptation of flexible devices under diverse application situations. To date, the design and synthesis of photofunctional materials with high flexibility, novel optical waveguide, and multi-port color-tunable emission in the same solid-state system remain an open challenge. Here, we have constructed new types of zero-dimensional organic metal halides (Au-4-dimethylaminopyridine [DMAP] and In-DMAP) with a rarely high elasticity and rather low loss coefficients for optical waveguide. Theoretical calculations on the intermolecular interactions showed that the high elasticity of 2 molecular crystalline materials was original from their herringbone structure and slip plane. Based on one-dimensional flexible microrods of 2 crystals and the 2-dimensional microplate of the Mn-DMAP, heterojunctions with multi-color and space-resolved optical waveguides have been fabricated. The formation mechanism of heterojunctions is based on the surface selective growth on account of the low lattice mismatch ratio between contacting crystal planes. Therefore, this work describes the first attempt to the design of metal-halide-based crystal heterojunctions with high flexibility and optical waveguide, expanding the prospects of traditional luminescent materials for smart optical devices, such as logic gates and multiplexers.

关键词： waveguide Crystal elasticity

Neddylation Regulation of Immune Responses

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Research 2024年第3期2023卷 545-559页

作者： Hongmei Mao Xin lin Yi sun Cancer Institute(Key Laboratory of Cancer Prevention and Intervention China National Ministry of Education)of the Second Affiliated Hospital and Institute of Translational MedicineZhejiang University School of MedicineHangzhou 310029China Institute for Immunology School of MedicineTsinghua UniversityBeijing 100084China Changping Laboratory Beijing 102206China Cancer Center of Zhejiang University Hangzhou 310029China Zhejiang Provincial Clinical Research Center for Cancer HangzhouZhejiang ProvinceChina Key Laboratory of Molecular Biology in Medical sciences HangzhouZhejiang ProvinceChina Research Center for Life science and Human Health Binjiang Institute of Zhejiang UniversityHangzhou 310053China.

Neddylation plays a vital role in post-translational modification, intricately shaping the regulation of diverse biological processes, including those related to cellular immune responses. In fact, neddylation exerts control over both innate and adaptive immune systems via various mechanisms. specifically, neddylation influences the function and survival of innate immune cells, activation of pattern recognition receptors and GMP-AMP synthase–stimulator of interferon genes pathways, as well as the release of various cytokines in innate immune reactions. Moreover, neddylation also governs the function and survival of antigen-presenting cells, which are crucial for initiating adaptive immune reactions. In addition, neddylation regulates T cell activation, proliferation, differentiation, survival, and their effector functions, thereby ensuring an appropriate adaptive immune response. In this review, we summarize the most recent findings in these aspects and delve into the connection between dysregulated neddylation events and immunological disorders, especially inflammatory diseases. Lastly, we propose future directions and potential treatments for these diseases by targeting neddylation.

关键词： activation thereby initiating

A lubrication model for bubbly oil lubrication with interfacial effect and thermal effect using the theory of multiphase mixtures

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friction 2024年第2期12卷 271-290页

作者： shaohua LI Xiaohui lin shuyun JIANG school of Mechanical Engineering Southeast UniversityNanjing 211189China

Bubbly oil lubrication is a type of lubrication ***,the lubrication model of the bubbly oil has not been thoroughly *** paper aims to investigate the modelling for bubbly oil lubrication considering the interfacial effect and thermal effect,and a theoretical model is established based on the theory of multiphase *** interfacial and thermal effects on the static characteristics of a thrust bearing are analyzed.A test rig for the thrust bearing is developed to measure the static characteristics of the bearing under bubbly oil *** results show that the bearing static characteristics,*** temperature rise,film thickness,friction torque,and volume flow,increase with consideration of three interfacial effects;the bearing temperature rise increases but the film thickness,friction torque,and volume flow rate decrease with consideration of the three thermal effects;the thermal effect on the bearing static characteristics is greater than the interfacial effect.

关键词： bubbly oil lubrication theory of multiphase mixtures interfacial effect thermal effect fluid bearing

flocking Effects of the stochastic Cucker-smale system with Noise

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Journal of systems science & Complexity 2024年第5期37卷 1978-1994页

作者： HAN Ning GE Bin LI lin school of Mathematical sciences Harbin Engineering University

In this paper, the flocking behavior of a Cucker-smale model with a leader and noise is studied in a finite time. The authors present a Cucker-smale system with two nonlinear controls for a complex network with stochastic synchronization in probability. Based on the finite-time stability theory of stochastic differential equations, the sufficient conditions for the flocking of stochastic systems in a finite time are obtained by using the Lyapunov function method. finally, the numerical simulation of the particle system is carried out for the leader and noise, and the correctness of the results is verified.

关键词： Cucker-smale model flocking behavior leader noise

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