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Learning topological defects formation with neural networks in a quantum phase transition

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Communications in Theoretical Physics 2024年第5期76卷 68-76页

作者： Han-Qing shi Hai-Qing Zhang Center for Gravitational Physics Department of Space ScienceBeihang UniversityBeijing 100191China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China

Neural networks possess formidable representational power,rendering them invaluable in solving complex quantum many-body *** they excel at analyzing static solutions,nonequilibrium processes,including critical dynamics during a quantum phase transition,pose a greater challenge for neural *** address this,we utilize neural networks and machine learning algorithms to investigate time evolutions,universal statistics,and correlations of topological defects in a one-dimensional transverse-field quantum Ising ***,our analysis involves computing the energy of the system during a quantum phase transition following a linear quench of the transverse magnetic field *** excitation energies satisfy a power-law relation to the quench rate,indicating a proportional relationship between the excitation energy and the kink ***,we establish a universal power-law relationship between the first three cumulants of the kink numbers and the quench rate,indicating a binomial distribution of the ***,the normalized kink-kink correlations are also investigated and it is found that the numerical values are consistent with the analytic formula.

关键词： neural networks machine learning transverse-field quantum Ising model kibble-zurek mechanism

A modified smoothed particle hydrodynamics method considering residual stress for simulating failure and its application in layered rock mass

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Journal of Mountain Science 2024年第6期21卷 2091-2112页

作者： XIA Chengzhi shi Zhenming KOU Huanjia Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China

Residual strength is an indispensable factor in evaluating rock fracture,yet the current Smoothed Particle Hydrodynamics(SPH)framework rarely considers its influence when simulating *** improved cracking strategy considering residual stress in the base bond SPH method was proposed to simulate failures in layered rocks and slopes and verified by experimental results and other simulation methods(i.e.,the discrete element method).Modified Mohr–Coulomb failure criterion was applied to distinguish the mixed failure of tensile and *** fracture markψwas introduced to improve the kernel function after tensile damage,and the calculation of residual stress after the damage was derived after shear *** simulations were carried out to evaluate its performance under different stress and scale conditions and to verify its effectiveness in realistically reproducing crack initiation and propagation and coalescence,even fracture and *** results indicate that the improved cracking strategy precisely captures the fracture and failure pattern in layered rocks and rock *** residual stress of brittle tock is correctly captured by the improved SPH *** improved SPH method that considers residual strength shows an approximately 13%improvement in accuracy for the safety factor of anti-dip layered slopes compared to the method that does not consider residual strength,as validated against analytical *** infer that the improved SPH method is effective and shows promise for applications to continuous and discontinuous rock masses.

关键词： Smoothed particle hydrodynamics Cracking strategy Residual stress Layered rock Crack propagation

Buckling optimization of curvilinear fiber-reinforced composite structures using a parametric level set method

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Frontiers of Mechanical Engineering 2024年第1期19卷 149-160页

作者： Ye TIAN Tielin shi Qi XIA State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Owing to their excellent performance and large design space,curvilinear fiber-reinforced composite structures have gained considerable attention in engineering fields such as aerospace and *** addition to the stiffness and strength of such structures,their stability also needs to be taken into account in the *** study proposes a level-set-based optimization framework for maximizing the buckling load of curvilinear fiber-reinforced composite *** the proposed method,the contours of the level set function are used to represent fiber *** a composite laminate with a certain number of layers,one level set function is defined by radial basis functions and expansion coefficients for each ***,the fiber angle at an arbitrary point is the tangent orientation of the contour through this *** the finite element of buckling,the stiffness and geometry matrices of an element are related to the fiber angle at the element *** study considers the parallelism constraint for fiber *** the sensitivity calculation of the objective and constraint functions,the method of moving asymptotes is utilized to iteratively update all the expansion coefficients regarded as design *** numerical examples under different boundary conditions are given to validate the proposed *** show that the optimized curved fiber paths tend to be parallel and equidistant regardless of whether the composite laminates contain holes or ***,the buckling resistance of the final design is significantly improved.

关键词： buckling optimization curvilinear fiber composite structure level set method manufacturing constraint

Three-dimensional limit variation analysis on the ultimate pullout capacity of the anchor cables based on the Hoek-Brown failure criterion

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Journal of Mountain Science 2024年第3期21卷 1036-1047页

作者： ZUO shi ZHAO Lianheng HU shihong College of Civil Engineering Changsha UniversityChangsha 410022China Hunan Provincial Key Laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering Structure Key Laboratory of Heavy-Haul Railway Engineering StructureMinistry of EducationCentral South UniversityChangsha 410075China College of Civil Engineering Central South UniversityChangsha 410075China

Only simplified two-dimensional model and a single failure mode are adopted to calculate the ultimate pullout capacity(UPC)of anchor cables in most previous *** study focuses on a more comprehensive combination failure mode that consists of bond failure of an anchorage body and failure of an anchored rock *** three-dimensional ultimate pullout capacity of the anchor cables is calculated based on the Hoek-Brown failure criterion and variation analysis *** numerical solution for the curvilinear function in fracture plane is obtained based on the finite difference theory,which more accurately reflects the failure state of the anchor cable,as opposed to that being assumed in *** results reveal that relying solely on a single failure mode for UPC calculations has limitations,as changes in parameter values not only directly impact the UPC value but also can alter the failure model and thus the calculation method.

关键词： Anchor cable Ultimate pullout capacity(UPC) Failure model Variation analysis Hoek-Brown failure criterion

Physiological and pathological functions of circular RNAs in the nervous system

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Neural Regeneration Research 2024年第2期19卷 342-349页

作者： Min Zhou shi Li Chuan Huang School of Life Sciences Chongqing UniversityChongqingChina

Circular RNAs(circRNAs)are a class of covalently closed single-stranded RNAs that are expressed during the development of specific cells and *** play crucial roles in physiological and pathological processes by sponging microRNAs,modulating gene transcription,controlling the activity of certain RNA-binding proteins,and producing functional peptides.A key focus of research at present is the functionality of circRNAs in the nervous system and several advances have emerged over the last 2 ***,the precise role of circRNAs in the nervous system has yet to be comprehensively *** this review,we first summarize the recently described roles of circRNAs in brain development,maturity,and ***,we focus on the involvement of circRNAs in various diseases of the central nervous system,such as brain cancer,chronic neurodegenerative diseases,acute injuries of the nervous system,and neuropathic pain.A better understanding of the functionality of circRNAs will help us to develop potential diagnostic,prognostic,and therapeutic strategies to treat diseases of the nervous system.

关键词： Alzheimer’s disease amyotrophic lateral sclerosis brain development circRNAs neuropathic pain Parkinson’s disease

Circulating tumor DNA in liquid biopsy: Current diagnostic limitation

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World Journal of Gastroenterology 2024年第15期30卷 2175-2178页

作者： shi-Cai Liu School of Medical Information Wannan Medical CollegeWuhu 241002Anhui ProvinceChina

With the rapid development of science and technology,cell-free DNA(cfDNA)is rapidly becoming an important biomarker for tumor diagnosis,monitoring and prognosis,and this cfDNA-based liquid biopsy technology has great potential to become an important part of precision *** is the total amount of free DNA in the systemic circulation,including DNA fragments derived from tumor cells and all other somatic *** cells release fragments of DNA into the bloodstream,and this source of cfDNA is called circulating tumor DNA(ctDNA).cfDNA detection has become a major focus in the field of tumor research in recent years,which provides a new opportunity for non-invasive diagnosis and prognosis of *** this paper,we discuss the limitations of the study on the origin and dynamics analysis of ctDNA,and how to solve these problems in the *** the future faces major challenges,it also con-tains great potential.

关键词： Cell-free DNA Circulating tumor DNA Liquid biopsy Cancer Diagnosis Prognosis

A Fuzzy Trust Management Mechanism with Dynamic Behavior Monitoring for Wireless Sensor Networks

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China Communications 2024年第5期21卷 177-189页

作者： Fu shiming Zhang Ping shi Xuehong School of Artificial Intelligence Chongqing University of EducationChongqing 400065China School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China

Traditional wireless sensor networks(WSNs)are typically deployed in remote and hostile environments for information *** wireless communication methods adopted by sensor nodes may make the network highly vulnerable to various *** encryption and authentication mechanisms cannot prevent attacks launched by internal malicious *** trust-based security mechanism is usually adopted to solve this problem in ***,the behavioral evidence used for trust estimation presents some uncertainties due to the open wireless medium and the inexpensive sensor ***,how to efficiently collect behavioral evidences are rarely *** address these issues,in this paper,we present a trust management mechanism based on fuzzy logic and a cloud ***,a type-II fuzzy logic system is used to preprocess the behavioral evidences and alleviate ***,the cloud model is introduced to estimate the trust values for sensor ***,a dynamic behavior monitoring protocol is proposed to provide a balance between energy conservation and safety *** results demonstrate that our trust management mechanism can effectively protect the network from internal malicious attacks while enhancing the energy efficiency of behavior monitoring.

关键词： behavior monitoring cloud fuzzy trust wireless sensor networks

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我国环境监理问题分析与发展策略探讨

环境与发展 2017年第5期29卷 219-220页

作者：石梦迪赵菁虹浙江仁欣环科院有限责任公司浙江宁波315199

近些年来,工业快速发展及农药化肥的大量使用导致我国的环境问题日益严峻。相关部门也采取了一系列环境保护措施,其中环境监理就是环境保护事业中一个重要的组成部分。本文首先介绍我国目前常见的三种环境监理模式,然后分析了我国环境... 详细信息

近些年来,工业快速发展及农药化肥的大量使用导致我国的环境问题日益严峻。相关部门也采取了一系列环境保护措施,其中环境监理就是环境保护事业中一个重要的组成部分。本文首先介绍我国目前常见的三种环境监理模式,然后分析了我国环境监理存在的一些问题,并根据这些问题提出了相应的发展策略。

关键词：环境保护环境监理问题分析发展策略

Study on the Impact of Massive Refracturing on the Fracture Network in Tight Oil Reservoir Horizontal Wells

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Fluid Dynamics & Materials Processing 2024年第5期20卷 1147-1163页

作者： Jianchao shi Yanan Zhang Wantao Liu Yuliang Su Jian shi Exploration and Development Research Institute Changqing Oilfield CompanyXi’an710018China National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields Xi’an710018China Key Laboratory of Unconventional Oil and Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580China

Class III tight oil reservoirs have low porosity and permeability,which are often responsible for low production rates and limited *** repeated fracturing is a well-known technique to fix some of these *** such methods,existing fractures are refractured,and/or new fractures are created to facilitate communication with natural *** study explored how different refracturing methods affect horizontal well fracture networks,with a special focus on morphology and related fluid flow *** particular,the study relied on the unconventional fracture model(UFM).The evolution of fracture morphology and flow field after the initial fracturing were analyzed *** simulation results indicated that increased formation energy and reduced reservoir stress differences can promote fracture *** was shown that the length of the fracture network,the width of the fracture network,and the complexity of the fracture can be improved,the oil drainage area can be increased,the distance of oil and gas seepage can be reduced,and the production of a single well can be significantly increased.

关键词： Type III tight oil reservoirs refracturing methods horizontal wells fracture network study fracture network evolution