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Stress tensor determination by modified hydraulic tests on pre-existing fractures:Method and stress constraints

Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1637-1648页

作者： Guiyun gao Chenghu Wang Ke gao National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing100085China Beijing Engineering Research Center of Earthquake Observation Beijing100085China Key Laboratory of Compound and Chained Natural Hazards Dynamics Ministry of Emergency Management of ChinaBeijing100085China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen518055China

The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor ***,the stress tensor determination based on the HTPF method requires at least six tests or a minimum of 14-15 tests(under different conditions)for reliable *** this study,we modified the HTPF method by considering the shear stress on each pre-existing fracture,which increased the number of equations for the stress tensor determination and decreased the number of tests *** shear stresses were attributed to different fractures by random sampling;therefore,the stress tensors were obtained by searching for the optimal solution using the least squares criterion based on the Monte Carlo ***,we constrained the stress tensor based on the tensile strength criterion,compressive strength criterion,and vertical stress *** inverted stress tensors were presented and analyzed based on the tensorial nature of the stress using the Euclidean mean stress *** stress-measurement campaigns in Weifang(Shandong Province,China)and Mercantour road tunnel(France)were implemented to highlight the validity and efficiency of the modified HTPF(M-HTPF)*** results showed that the M-HTPF method can be applied for stress tensor inversion using only three to four tests on pre-existing fractures,neglecting the stress *** inversion results were confined to relatively small distribution dispersions and were significantly reliable and stable due to the shear stresses on the fractures and the stress constraints *** M-HTPF method is highly feasible and efficient for complete stress tensor determination in a single borehole.

关键词： Stress tensor Hydraulic tests on pre-existing fractures Mean stress Stress constraint Hydraulic fracturing

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Association of preschool children behavior and emotional problems with the parenting behavior of both parents

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World Journal of Clinical Cases 2024年第6期12卷 1084-1093页

作者： Su-Mei Wang Shuang-Qin Yan Fang-Fang Xie Zhi-Ling Cai Guo-peng gao Ting-Ting Weng Fang-Biao Tao Department of Child Health Ma’anshan Maternal and Child Health CenterMa’anshan 243011Anhui ProvinceChina Department of Maternal Child and Adolescent HealthSchool of Public HealthAnhui Medical UniversityHefei 230032Anhui ProvinceChina

BACKGROUND Parental behaviors are key in shaping children’s psychological and behavioral development,crucial for early identification and prevention of mental health issues,reducing psychological trauma in *** To investigate the relationship between parenting behaviors and behavioral and emotional issues in preschool *** From October 2017 to May 2018,7 kindergartens in Ma’anshan City were selected to conduct a parent self-filled questionnaire-Health Development Survey of Preschool ***’s Strength and Difficulties Questionnaire(Parent Version)was applied to measures the children’s behavioral and emotional *** behavior was evaluated using the Parental Behavior *** logistic regression model was used to analyze the association between the detection rate of preschool children’s behavior and emotional problems and their parenting *** High level of parental support/participation was negatively correlated with conduct problems,abnormal hyperactivity,abnormal total difficulty scores and abnormal prosocial behavior *** level of maternal support/participation was negatively correlated with abnormal emotional symptoms and abnormal peer interaction in *** level of parental hostility/coercion was positively correlated with abnormal emotional symptoms,abnormal conduct problems,abnormal hyperactivity,abnormal peer interaction,and abnormal total difficulty scores in children(all P0.05),after calculating ratio of odds ratio *** Our study found that parenting behaviors are associated with behavioral and emotional issues in preschool ***,the more supportive or involved the parents are,the fewer behavioral and emotional problems the children experience;conversely,the more hostile or contro

关键词： Children Preschool age Parenting Behavioral Parenting problems

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New Results in Cooperative Adaptive Optimal Output Regulation

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Journal of Systems Science & Complexity 2024年第1期37卷 253-272页

作者： DONG Yuchen gao Weinan JIANG Zhong-Ping State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China Department of Electrical and Computer Engineering Tandon School of EngineeringNew York UniversityBrooklynNY 11201USA

This paper investigates the cooperative adaptive optimal output regulation problem of continuous-time linear multi-agent *** the multi-agent system dynamics are uncertain,solving regulator equations and the corresponding algebraic Riccati equations is challenging,especially for high-order *** this paper,a novel method is proposed to approximate the solution of regulator equations,i.e.,gradient descent *** is worth noting that this method obtains gradients through online data rather than model information.A data-driven distributed adaptive suboptimal controller is developed by adaptive dynamic programming,so that each follower can achieve asymptotic tracking and disturbance ***,the effectiveness of the proposed control method is validated by simulations.

关键词： Adaptive dynamic programming cooperative output regulation gradient descent method multi-agent systems.

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Activation of endogenous neurogenesis and angiogenesis by basic fibroblast growth factor-chitosan gel in an adult rat model of ischemic stroke

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Neural Regeneration Research 2024年第2期19卷 409-415页

作者： Hongmei Duan Shulun Li peng Hao Fei Hao Wen Zhao Yudan gao Hui Qiao Yiming Gu Yang Lv Xinjie Bao Kin Chiu Kwok-Fai So Zhaoyang Yang Xiaoguang Li Department of Neurobiology School of Basic Medical SciencesCapital Medical UniversityBeijingChina Beijing Key Laboratory for Biomaterials and Neural Regeneration School of Engineering MedicineBeihang UniversityBeijingChina Department of Epidemiology and Statistics School of Public Health and ManagementNingxia Medical UniversityYinchuanNingxia Hui Autonomous RegionChina Department of Physical Education Capital University of Economics and BusinessmBeijingChina Department of Neurosurgery Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Psychology State Key Lab of Brain and Cognitive SciencesThe University of Hong KongHong Kong Special Administration RegionChina Guangdong-Hongkong-Macao Institute of CNS Regeneration Ministry of Education CNS Regeneration Collaborative Joint LaboratoryJinan UniversityGuangzhouGuangdong ProvinceChina Bioland Laboratory(Guangzhou Regenerative Medicine and Health Guangdong Laboratory) GuangzhouGuangdong ProvinceChina Department of Ophthalmology and State Key Laboratory of Brain and Cognitive Sciences The University of Hong KongHong Kong Special Administration RegionChina Center for Brain Science and Brain-Inspired Intelligence Guangdong-Hong Kong-Macao Greater Bay AreaGuangzhouGuangdong ProvinceChina Co-innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Biomedical Engineering School of Biological Science and Medical EngineeringBeihang UniversityBeijingChina

Attempts have been made to use cell transplantation and biomaterials to promote cell proliferation,differentiation,migration,and survival,as well as angiogenesis,in the context of brain ***,whether bioactive materials can repair the damage caused by ischemic stroke by activating endogenous neurogenesis and angiogenesis is still *** this study,we applied chitosan gel loaded with basic fibroblast growth factor to the stroke cavity 7 days after ischemic stroke in *** gel slowly released basic fibroblast growth factor,which improved the local microenvironment,activated endogenous neural stem/progenitor cells,and recruited these cells to migrate toward the penumbra and stroke cavity and subsequently differentiate into neurons,while enhancing angiogenesis in the penumbra and stroke cavity and ultimately leading to partial functional *** study revealed the mechanism by which bioactive materials repair ischemic strokes,thus providing a new strategy for the clinical application of bioactive materials in the treatment of ischemic stroke.

关键词： adult endogenous neurogenesis angiogenesis basic fibroblast growth factor-chitosan gel chitosan functional recovery ischemic stroke neural stem cell newborn neuron

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A combined method using Lattice Boltzmann Method(LBM)and Finite Volume Method(FVM)to simulate geothermal reservoirs in Enhanced Geothermal System(EGS)

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Journal of Groundwater Science and Engineering 2024年第2期12卷 132-146页

作者： Xiang gao Tai-lu Li Yu-wen Qiao Yao Zhang ze-yu Wang School of Energy and Environmental Engineering Hebei University of TechnologyTianjin 300401China

With the development of industrial activities,global warming has accelerated due to excessive emission of CO_(2).Enhanced Geothermal System(EGS)utilizes deep geothermal heat for power *** porous medium theory is commonly employed to model geothermal reservoirs in EGS,Hot Dry Rock(HDR)presents a challenge as it consists of impermeable granite with zero porosity,potentially distorting the physical *** address this,the Lattice Boltzmann Method(LBM)is employed to simulate CO_(2)flow within geothermal reservoirs and the Finite Volume Method(FVM)to solve the energy conservation equation for temperature *** combined method of LBM and FVM is imple-mented using *** results showed that the Reynolds numbers(Re)of 3,000 and 8,000 lead to higher heat extraction rates from geothermal ***,higher Re values may accelerate thermal breakthrough,posing challenges to EGS ***,non-equilibrium of density in fractures becomes more pronounced during the system's life cycle,with non-Darcy's law becoming significant at Re values of 3,000 and 8,*** stratification due to buoyancy effects significantly impacts temperature distribution within geothermal reservoirs,with buoyancy effects at Re=100 under gravitational influence being *** Re values(3,000 and 8,000)induce stronger forced convection,leading to more uniform density *** addition of proppant negatively affects heat transfer performance in geothermal reservoirs,especially in single *** engineering considerations should determine the quantity of proppant through detailed numerical simulations.

关键词： Lattice boltzmann method Finite volume method Enhanced geothermal system Geothermal reservoir Proppant Re Heat extraction rate

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Trajectory tracking guidance of interceptor via prescribed performance integral sliding mode with neural network disturbance observer

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Defence Technology（防务技术） 2024年第2期32卷 412-429页

作者： Wenxue Chen Yudong Hu Changsheng gao Ruoming An School of Astronautics Harbin Institute of TechnologyHarbin 150001China

This paper investigates interception missiles’trajectory tracking guidance problem under wind field and external disturbances in the boost ***,the velocity control in such trajectory tracking guidance systems of missiles is *** our contribution,the velocity control channel is designed to deal with the intractable velocity problem and improve tracking *** global prescribed performance function,which guarantees the tracking error within the set range and the global convergence of the tracking guidance system,is first proposed based on the traditional ***,a tracking guidance strategy is derived using the integral sliding mode control techniques to make the sliding manifold and tracking errors converge to zero and avoid ***,an improved switching control law is introduced into the designed tracking guidance algorithm to deal with the chattering problem.A back propagation neural network(BPNN)extended state observer(BPNNESO)is employed in the inner loop to identify *** obtained results indicate that the proposed tracking guidance approach achieves the trajectory tracking guidance objective without and with disturbances and outperforms the existing tracking guidance schemes with the lowest tracking errors,convergence times,and overshoots.

关键词： BP network neural Integral sliding mode control(ISMC) Missile defense Prescribed performance function(PPF) State observer Tracking guidance system

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An Integrated External Archive Local Disturbance Mechanism for Multi-Objective Snake Optimizer

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Chinese Journal of Electronics 2024年第4期33卷 989-996页

作者： Leifu gao Zheng LIU Institute for Optimization and Decision Analytics Liaoning Technical University

It is an interesting research direction to develop new multi-objective optimization algorithms based on meta-heuristics. Both the convergence accuracy and population diversity of existing methods are not *** paper proposes an integrated external archive local disturbance mechanism for multi-objective snake optimizer(IMOSO) to overcome the above shortcomings. There are two improved strategies. The adaptive mating between subpopulations strategy introduces the special mating behavior of snakes with multiple husbands and wives into the original snake optimizer. Some positions are updated according to the dominated relationships between the newly created individuals and the original individuals. The external archive local disturbance mechanism is used to re-search partial non-inferior solutions with poor diversities. The perturbed solutions are non-dominated sorting with the generated solutions by the next iteration to update the next external archive. The main purpose of this mechanism is to make full use of the non-inferior solution information to better guide the population evolution. The comparison results of the IMOSO and 7 state-of-the-art algorithms on WFG benchmark functions show that IMOSO has better convergence and population diversity.

关键词： Accuracy Sociology Metaheuristics Diversity methods Benchmark testing Statistics Convergence

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Zwitterionic additive for high-performance pure-blue perovskite light-emitting diodes

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Advanced Photonics 2024年第2期6卷 5-6页

作者： Hongling Yu Feng gao Linköping University Department of PhysicsChemistry and Biology(IFM)LinköpingSweden

Metal halide perovskites have emerged as promising candidates for light-emitting diodes(LEDs)due to their cost effectiveness,solution processability,and impressive luminescence.1At present,the external quantum efficiencies(EQEs)of sky-blue,2green,3red,4and near-infrared perovskite LEDs(Pe LEDs)have exceeded 20%,5demonstrating significant potential for future display and communication ***,achieving high-performance pure-blue Pe LEDs with a peak wavelength of 460-470 nm,which is an indispensable color.

关键词： diodes performance light

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A ratiometric optical thermometer with dual-color emission based on Eu^(2+)-doped CsCu_(2)I_(3) microcrystals

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Journal of Rare Earths 2024年第8期42卷 1429-1436,I0001页

作者： Xiaorong Li Ge gao Kaiyu Wang Zhaoqiong Chen zejiang gao Qingyong Qin Li Chen Bingsuo Zou State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures School of Physical Science and TechnologyGuangxi UniversityNanning530004China School of Resources Environments and MaterialsGuangxi UniversityNanning530004China

With the increasing demand for non-co ntact fluorescence intensity ratio-based optical thermometry,novel phosphor materials with high-efficiency,dual-emitting centers,and differentiable temperature sensitivity are highly desired,In this wo rk,rare earth Eu^(2+) ions were incorporated Wnto CsCu_(2)I_(3) microcrystals by solidstate reaction,Under a single UV excitation,the as-synthesized samples exhibit two emissions:452 nm blue emission from the 5d→4f transition of Eu^(2+)and 582 nm yellow emission from self-trapped exciton e mission of CsCu_(2)I_(3).The photoluminescence quantum yield reaches to 50%,The dual-band emission of Eu^(2+)-doped CsCu_(2)I_(3) shows different temperature responses in the range of 260-360 *** on fluorescence intensity ratio technology,the maximum absolute sensitivity and re Iative sensitivity are 0.091 K^(-1)(at 360 K) and 2.60%/K(at 260 K),*** results suggest that Eu^(2+)-doped GsCu_(2)I_(3) could be a good candidate for highly sensitive optical thermometer.

关键词： CsCu_(2)I_(3) Eu^(2+)-doping Fluorescence intensity ratio Optical thermometer Rare earths

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HiFAST:An HIdata calibration and imaging pipeline for FAST

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 182-199页

作者： Yingjie Jing Jie Wang Chen Xu Ziming Liu Qingze Chen Tiantian Liang Jinlong Xu Yixian Cao Jing Wang Huijie Hu Chuan-peng Zhang Qi Guo Liang gao Mei Ai Hengqian Gan Xuyang gao Jinlin Han Ligang Hou Zhipeng Hou peng Jiang Xu Kong Fujia Li zerui Liu Li Shao Hengxing Pan Jun Pan Lei Qian Jinghai Sun Ningyu Tang Qingliang Yang Bo Zhang Zhiyu Zhang Ming Zhu National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 02206China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 55000China Max Planck Institute for Extraterrestrial Physics Garching 85748Germany Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Institute of Computational Cosmology Department of PhysicsUniversity of DurhamDurham DHI 3LEUK CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Deep Space Exploration Laboratory/Department of Astronomy University of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Astrophysics Department of PhysicsUniversity of OxfordOxford OX/3RHUK College of Earth Sciences Guilin University of TechnologyGuilin 541004China Department of Physics Anhui Normal UniversityWuhu 241002China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityNanjing 20023China

The Five-hundred-meter Aperture Spherical radio Telescope(FAST)has the largest aperture and a 19-beam L-band receiver,making it powerful for investigating the neutral hydrogen atomic gas(HI)in the *** present HiFAST(https://***),a dedicated,modular,and self-contained calibration and imaging pipeline for processing the H?data of *** pipeline consists of frequency-dependent noise diode calibration,baseline fitting,standing wave removal using an FFT-based method,flux density calibration,stray radiation correction,and gridding to produce data *** modules can be combined as needed to process the data from most FAST observation modes:tracking,drift scanning,On-The-Fly mapping,and most of their *** HiFAST,the root-mean-square(RMS)noises of the calibrated spectra from all 19 beams were only slightly(~5%)higher than the theoretical *** results for the extended source M33 and the point sources are consistent with the results from *** moment maps(0,1 and 2)of M33 agree well with the results from the Arecibo Galaxy Environment Survey(AGES)with a fractional difference of less than 10%.For a common sample of 221 sources with signal-to-noise ratio S/N>10 from the Arecibo Legacy Fast ALFA(ALFALFA)survey,the mean value of fractional difference in the integrated flux density,Sint,between the two datasets is approximately 0.005%,with a dispersion of 15.4%.Further checks on the integrated flux density of 23 sources with seven observations indicate that the variance in the flux density of the source with luminous objects(Sint>2.5 Jy km s-1)is less than 5%.Our tests suggest that the FAST telescope,with the efficient,precise,and user-friendly pipeline HiFAST,will yield numerous significant scientific findings in the investigation of the H?in the universe.

关键词： fractional luminous correction

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