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Applying Machine Learning Approach to Explore Childhood Circumstances and Self-Rated Health in Old Age-china and the US,2020-2021

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china CDC weekly 2024年第11期6卷 213-218,I0008-I0013页

作者： Shutong Huo Derek Feng Thomas M.Gill xi Chen Department of Health Society&BehaviorPublic HealthUniversity of CaliforniaIrvineCAUSA Department of Statistics and Data Science Yale UniversityNew HavenCTUS Department of Internal Medicine Yale School of MedicineNew HavenCTUS Department of Health Policy and Management Yale School of Public HealthNew HavenCTUS Department of Economics Yale UniversityNew HavenCTUS.

Introduction:Childhood circumstances impact senior health,prompting the introduction of machine learning methods to assess their individual and collective contributions to senior ***:Using health and retirement study(HRS)and china Health and Retirement Longitudinal Study(CHARLS),we analyzed 2,434 American and 5,612 Chinese participants aged 60 and *** inference trees and forests were employed to estimate the influence of childhood circumstances on self-rated health(SRH).Results:The conventional method estimated higher inequality of opportunity(IOP)values in both china(0.039,accounting for 22.67%of the total Gini coefficient 0.172)and the US(0.067,accounting for 35.08%of the total Gini coefficient 0.191).In contrast,the conditional inference tree yielded lower estimates(china:0.022,accounting for 12.79%of 0.172;US:0.044,accounting for 23.04%of 0.191),as did the forest(china:0.035,accounting for 20.35%of 0.172;US:0.054,accounting for 28.27%of 0.191).Childhood health,financial status,and regional differences were key determinants of senior *** conditional inference forest consistently outperformed others in predictive accuracy,as demonstrated by lower out-of-sample mean squared error(MSE).Discussion:The findings emphasize the need for early-life interventions to promote health equity in aging *** learning showcases the potential in identifying contributing factors.

关键词： collective inequality estimates

A flame-retardant binder with high polysulfide affinity for safe and stable lithium–sulfur batteries

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Science china Chemistry 2024年第3期67卷 1028-1036页

作者： Guowei Yu Guofeng Ye Cheng Wang Chenyang Wang Zhaoyun Wang Pu Hu Yu Li xi-xi Feng Shuang-Jie Tan Min Yan Sen xin Zhitian Liu Hubei Key Laboratory of Plasma Chemistry and Advanced Materials Hubei Engineering Technology Research Center of Optoelectronic and New Energy MaterialsSchool of Materials Science and EngineeringWuhan Institute of TechnologyWuhan 430205China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China university of Chinese Academy of Sciences Beijing 100049China

Lithium-sulfur(Li-S) batteries have shown promises for the next-generation, high-energy electrochemical storage, yet are hindered by rapid performance decay due to the polysulfide shuttle in the cathode and safety concerns about potential thermal runaway. To address the above challenges, herein, we show a flame-retardant cathode binder that simultaneously improves the electrochemical stability and safety of batteries. The combination of soft and hard segments in the polymer framework of binders allows high flexibility and mechanical strength for adapting to the drastic volume change during the Li(de)intercalation of the S cathode. The binder contains a large number of polar groups, which show the high affinity to polysulfides so that they help to anchor active S species at the cathode. These polar groups also help to regulate and facilitate the Li-ion transport, promoting the kinetics of polysulfide conversion reaction. The binder contains abundant phosphine oxide groups, which, in the case of battery's thermal runaway, decompose and release PO· radicals to quench the combustion reactions and stop the fire. Consequently, Li-S batteries using the new cathode binder show the improved electrochemical performance, including a low-capacity decay of 0.046% per cycle for 800 cycles at 1 C and favorable rate capabilities of up to 3 C. This work offers new insights on the practical realization of high-energy rechargeable batteries with stable storage electrochemistry and high safety.

关键词： lithium–sulfur battery polymer binder polysulfide affinity flame retardancy

DEFORMATION AND MICROFRACTURE OF GRANULAR BAINITE

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Acta Metallurgica Sinica(English Letters) 1992年第6期5卷 432-435页

作者： CHEN Huangpu xi’an Jiaotong university,xi’an,china Lecturer,The Research institute for Strength of Metals,xi’an Jiaotong university,xi’an 710049,china xi'an Jiaotong Univ Xi'an China

Relationship among deformation history,fracture process and stress distribution of granular bainite has been *** main process of fracture of granular bainite is the forma- *** and coalescence of the *** though the microcracks have formed at the earlier stage of deformation,they are not fateful for fracture because in the successive deformation stage the microcracks change their orientation toward the tensile *** strain hardening rate of granular bainite has a minimal value during the deformation process. Before and after the strain of the minimal value,the material shows different stress distribu- tion and microfracture mechanism.

关键词： granular bainite microfracture strain hardening rate

Multi-source data integration and multi-scale modeling framework for progressive prediction of complex geological interfaces in tunneling

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Underground Space 2024年第2期15卷 1-25页

作者： Jingxiao Wang Peinan Li xiaoying Zhuang xiaojun Li xi Jiang Jun Wu Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China College of Environmental Science and Engineering Donghua UniversityShanghai 201620China institute of Photonics Department of Mathematics and PhysicsLeibniz University HannoverHannover 30167Germany Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 100872China College of Civil Engineering Shanghai Normal UniversityShanghai 200233China

A reliable geological model plays a fundamental role in the efficiency and safety of mountain tunnel ***,regional models based on limited survey data represent macroscopic geological environments but not detailed internal geological characteristics,especially at tunnel portals with complex geological *** paper presents a comprehensive methodological framework for refined modeling of the tunnel surrounding rock and subsequent mechanics analysis,with a particular focus on natural space distortion of hard-soft rock interfaces at tunnel *** progressive prediction of geological structures is developed considering multi-source data derived from the tunnel survey and excavation *** improve the accuracy of the models,a novel modeling method is proposed to integrate multi-source and multi-scale data based on data extraction and potential field ***,a regional-scale model and an engineering-scale model are built,providing a clear insight into geological phenomena and supporting numerical *** addition,the proposed framework is applied to a case study,the Long-tou mountain tunnel project in Guangzhou,china,where the dominant rock type is *** results show that the data integration and modeling methods effectively improve model structure *** improved model’s calculation deviation is reduced by about 10%to 20%in the mechanical *** study contributes to revealing the complex geological environment with singular interfaces and promoting the safety and performance of mountain tunneling.

关键词： Mountain tunnel Geological modeling Multi-source data Progressive prediction Tunnel portals

Pupillometry Analysis of Rapid Serial Visual Presentation at Five Presentation Rates

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Tsinghua Science and Technology 2024年第2期29卷 543-552页

作者： xi Luo Yanfei Lin Rongxiao Guo xirui Zhao Shangen Zhang xiaorong Gao School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China School of Medicine Tsinghua UniversityBeijing 100084China

In this study,the effect of presentation rates on pupil dilation is investigated for target recognition in the Rapid Serial Visual Presentation(RSVP)*** this experiment,the RSVP paradigm with five different presentation rates,including 50,80,100,150,and 200 ms,is *** pupillometry data of 15 subjects are collected and *** pupillometry results reveal that the peak and average amplitudes for pupil size and velocity at the 80-ms presentation rate are considerably higher than those at other presentation *** average amplitude of pupil acceleration at the 80-ms presentation rate is significantly higher than those at the other presentation *** latencies under 50-and 80-ms presentation rates are considerably lower than those of 100-,150-,and 200-ms presentation ***,no considerable differences are observed in the peak,average amplitude,and latency of pupil size,pupil velocity,and acceleration under 100-,150-,and 200-ms presentation *** results reveal that with the increase in the presentation rate,pupil dilation first increases,then decreases,and later reaches *** 80-ms presentation rate results in the largest point of pupil *** correlation is observed between pupil dilation and recognition accuracy under the five presentation rates.

关键词： pupil dilation presentation rate Rapid Serial Visual Presentation(RSVP)

Experimental investigation of dynamic characteristics of leaching tubing for solution mining of salt cavern carbon and energy storage

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Petroleum Science 2024年第4期21卷 2703-2722页

作者： Yin-Ping Li xin-Bo Ge xi-Lin Shi Hong-Ling Ma State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences university of Chinese Academy of Sciences College of Energy and Mining Engineering Shandong University of Science and Technology State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and Technology

Salt caverns are extensively utilized for storing various substances such as fossil energy, hydrogen,compressed air, nuclear waste, and industrial solid waste. In china, when the salt cavern is leached through single-well water solution mining with oil as a cushion, engineering challenges arise with the leaching tubing, leading to issues like damage and instability. These problems significantly hinder the progress of cavern construction and the control of cavern shape. The primary cause of this is the flowinduced vibration instability of leaching tubing within a confined space, which results in severe bending or damage to the tubing. This study presents a model experimental investigation on the dynamic characteristics of leaching tubing using a self-developed liquid-solid coupling physical model experiment apparatus. The experiment utilizes a silicone-rubber pipe(SRP) and a polycarbonate pipe(PCP) to examine the effects of various factors on the dynamic stability of cantilevered pipes conveying fluid. These factors include external space constraint, flexural rigidity, medium outside the pipe, overhanging length, and end conditions. The experiments reveal four dynamic response phenomena: water hammer, static buckling, chaotic motion, and flutter instability. The study further demonstrates that the length of the external space constraint has a direct impact on the flutter critical flow velocity of the cantilevered pipe conveying fluid. Additionally, the flutter critical flow velocity is influenced by the end conditions and different external media.

关键词： Salt cavern storage Solution mining Leaching tubing Experimental investigation Flutter instability

New evidence for lack of CMB power on large scales

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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 567-570页

作者： LIU Hao1 & LI TiPei1,2,3 1 Key Laboratory of Particle Astrophysics, institute of High Energy physics, Chinese Academy of Sciences, Beijing 100049, china 2 Department of physics & Center for Astrophysics, Tsinghua university, Beijing 100084, china 3 Department of Engineering physics & Center for Astrophysics, Tsinghua university, Beijing 100084, china 1. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China2. Department of Physics & Center for Astrophysics Tsinghua University Beijing 100084 China3. Department of Engineering Physics & Center for Astrophysics Tsinghua University Beijing 100084 China

A digitalized temperature map is recovered from the first light sky survey image published by the Planck team, from which an angular power spectrum of the cosmic microwave background (CMB) is derived. The amplitudes of the low multipoles (low-l) measured from the preliminary Planck power spectrum are significantly lower than those reported by the WMAP team. Possible systematical effects are far from enough to explain the observed low-l differences.

关键词： cosmology cosmic microwave background data analysis

Quantum statistical entropy corresponding to cosmic horizon in five-dimensional spacetime

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Science china(physics,Mechanics & Astronomy) 2008年第2期51卷 140-146页

作者： ZHAO Ren1,2 & ZHANG ShengLi1 1 Department of Applied physics, xi’an Jiaotong university, xi’an 710049, china 2 Department of physics, Shanxi Datong university, Datong 037009, china Department of Applied physics Xi’an Jiaotong University Xi’an 710049 China Department of physics Shanxi Datong University Datong 037009 China

The generalized uncertainty relation is introduced to calculate the quantum statis-tical entropy corresponding to cosmic horizon. By using the new equation of state density motivated by the generalized uncertainty relation, we discuss entropies of Bose field and Fermi field on the background of five-dimensional spacetime. In our calculation, we need not introduce cutoff. There is no divergent logarithmic term in the original brick-wall method. And it is obtained that the quantum statistical en-tropy corresponding to cosmic horizon is proportional to the area of the horizon. Further it is shown that the entropy corresponding to cosmic horizon is the entropy of quantum state on the surface of horizon. The black hole's entropy is the intrinsic property of the black hole. The entropy is a quantum effect. In our calculation, by using the quantum statistical method, we obtain the partition function of Bose field and Fermi field on the background of five-dimensional spacetime. We provide a way to study the quantum statistical entropy corresponding to cosmic horizon in the higher-dimensional spacetime.

关键词： quantum statistical entropy generalized uncertainty relation high-dimensional spacetime

Effect of excess Y_2O_3 addition on the physical properties of melt processed YBCO bulks

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Science china(physics,Mechanics & Astronomy) 2004年第1期47卷 17-23页

作者： YANG Wanmin1,2,3, ZHOU Lian2, FENG Yong2, ZHANG Pingxiang2, WU Minzhi3 & W. GAWALEK3 1. Department of physics, Shaanxi Normal university, xi抋n 710062, china 2. northwest institute for Nonferrous Metal Research. xi抋n 710016, china 3. institute fur Physikalische Hochtechnologie e.V(IPHT), Jena, Germany Correspondence should be addressed to Yang Wanmin (email: wm-yang@***) Received June 27, 2003 1. Department of physics Shaanxi Normal University 710062 Xi’an China 2. northwest institute for Nonferrous Metal Research 710016 Xi’an China 3. institute fur Physikalische Hochtechnologie e.V (IPHT) Jena Germany

The YBCO superconductors with Y2O3 addition were prepared by a modified melt textured process and the effects of excess Y2O3 addition on the physical properties of melt textured YBCO have been investigated. It is found that the melt temperature of YBCO samples decreases drastically with the increasing Y2O3, and the maximum levitation forces are drastically different for samples with different Y2O3 addition. It is also found that the optimal Y2O3 addition to YBCO is about 10wt%. Considering the microstructure and the starting composition, the results are well discussed and interpreted.

关键词： YBCO superconductor, melt growth, Y2O3 addition, levitation force.