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The Slow Dynamics of the Zero-Range Process in the Framework of the Traps Model

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Chinese Physics Letters 2012年第5期29卷 59-62页

作者： qi Kai TAnG Ming cui Ai-Xiang FU Yan Web Sciences Center University of Electronic Science and Technology of ChinaChengdu 610054

The relaxation dynamics of the zero-range process (ZRP) has been an interesting *** this study,we set up the relationship between the ZRP and a model of traps,and investigate the slow dynamics of the ZRP in the framework of the trap *** statistical quantities such as the average rest time,the particle distribution,the two-time correlation function and the average escape time,we find that the particle interaction,especially the resulting condensation,can significantly influence the *** the stationary state,both the average rest time and the average escape time caused by the attraction among particles are obtained *** the transient state,a hierarchical nature of the aging dynamics is revealed by both simulations and scaling ***,by comparing the particle diffusion in both the transient state and the stationary state,we find that the closer the ZRP systems approach the stationary state,the more slowly the particles diffuse.

关键词： stationary dynamics transient

A novel TOA estimation method with effective nLOS error reduction

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 32-37页

作者： ZHAnG Yi-heng cui qi-mei LI Yu-xiang ZHAnG Ping Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications Ministry of Education Wireless Technology Innovation Institute (WTI) Beijing 100876 China

It is well known that non-line-of-sight （nLOS） error has been the major factor impeding the enhancement of accuracy for time of arrival （TOA） estimation and wireless positioning. This article proposes a novel method of TOA estimation effectively reducing the nLOS error by 60%, comparing with the traditional timing and synchronization method. By constructing the orthogonal training sequences, this method converts the traditional TOA estimation to the detection of the first arrival path （FAP） in the nLOS multipath environment, and then estimates the TOA by the round-trip transmission （RTT） technology. Both theoretical analysis and numerical simulations prove that the method proposed in this article achieves better performance than the traditional methods.

关键词： TOA estimation nLOS error B3G

Hearing Loss and Depressive Symptoms Among Community-Dwelling Older Adults-Liaoning,Henan,and Guangdong Provinces,China,2019-2020

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China CDC weekly 2024年第32期6卷 811-815,I0002页

作者： Ran An Lu cui Liyuan Yang Han Zhang Shige qi Haoyan Guo national Center for Chronic and noncommunicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina School of Public Health Capital Medical UniversityBeijingChina Chengnan Community Health Service Center of Changping District BeijingChina national Institute for nutrition and Health Chinese Center for Disease Control and PreventionBeijingChina

Summary What is already known about this topic?More than half of Chinese older adults over 60 are suffering from hearing loss(HL),which might increase the risk of depressive *** is added by this report?The results indicated a significant association between severe or profound HL and depressive symptoms,characterized by notable age and gender disparities,particularly among women aged 60–74 years *** are the implications for public health practice?Timely intervention and treatment for elderly individuals with HL,particularly younger female elders suffering from severe or profound HL,are pivotal in reducing depressive symptom rates and are key policy considerations.

关键词： younger policy suffering

Cooperative localization for next-generation converged networks with closed-form solution

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 56-61页

作者： ZHAnG Yi-heng cui qi-mei ZHAnG Ping TAO Xiao-feng Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China Research Institute of Highway (RIOH) Transport Consulats Ltd Beijing 100088 China

In this article, a novel cooperative wireless localization scheme based on information fusion is proposed. The scheme combines large-scale arrival time and small-scale distance measurements obtained from the next-generation converged networks. The maximum likelihood （ML） estimate of the terminal＇s position is derived with closed-form solution, and the Cramer-Rao lower bound （CRLB） of the estimate error is investigated. Both theoretical analysis and simulation results verify that the proposed localization scheme can significantly enhance the location precision. Moreover, the mean square error of position estimate approximates the CRLB when the number of reference stations increases, which indicates that the proposed ML estimator is asymptotically efficient.

关键词： cooperative localization time of arrival (TOA) next-generation converged network large scale small scale

Interface engineering of Zn meal anodes using electrochemically inert Al_(2)O_(3)protective nanocoatings

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nano Research 2022年第8期15卷 7227-7233页

作者： Rui Wang qiongfei Wu Minjie Wu Jiaxian Zheng Jian.cui qi Kang Zhengbing qi JiDong Ma Zhoucheng Wang Hanfeng Liang State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Key Laboratory of Functional Materials and Applications of Fujian Province School of Materials Science and EngineeringXiamen University of TechnologyXiamen 361024China Department of Polymer Science and Engineering Shanghai Key Laboratory of Electrical Insulation and Thermal AgeingShanghai Jiao Tong UniversityShanghai 200240China

Aqueous rechargeable Zn-ion batteries are regarded as a promising alternative to lithium-ion batteries owing to their high energy density,low cost,and high ***,their commercialization is severely restricted by the Zn dendrite formation and side ***,we propose that these issues can be minimized by modifying the interfacial properties through introducing electrochemically inert Al_(2)O_(3)nanocoatings on Zn meal anodes(Al_(2)O_(3)@Zn).The Al_(2)O_(3)nanocoatings can effectively suppress both the dendrite growth and side *** a result,the Al_(2)O_(3)@Zn symmetric cells show excellent electrochemical performance with a long lifespan of more than 4,000 h at 1 mA·cm^(−2)and 1 mAh·cm^(−2).Meanwhile,the assembled Al_(2)O_(3)@Zn//V_(2)O_(5)full cells can deliver a high capacity(236.2 mAh·g^(−1))and long lifespan with a capacity retention of 76.11%after 1,000 cycles at 4 A·g^(−1).

关键词： aqueous Zn-ion batteries Zn dendrites side reactions Al2O3 protective nanocoatings interface engineering

neodymium Organic Sulfonate Complexes: Tunable Electronegativity/Steric Hindrance and Application in Controlled Cis-1,4-polymerization of Butadiene

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Chinese Journal of Polymer Science 2019年第3期37卷 208-215页

作者： Jian-Yun He Long cui Yan-Long qi Quan-Quan Dai Chen-Xi Bai Key Laboratory of High-Performance Synthetic Rubber and its Composite Materials Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Rare earth catalysts possessing characteristics of cation-anion ion pair show advantages of adjusting electronegativity and steric hindrance of metal active sites, which can control the catalytic performance and stereoselectivity better than those of traditional metallocene and Ziegler-natta catalysts in diene polymerization. In this work, a series of neodymium organic sulfonate complexes,nd(CF_3SO_3)_3·x H_2O·y L(x, y: the coordination number; L refers to an organic electron donating ligand, such as acetylacetone(acac), isooctyl alcohol(IAOH), tributyl phosphate(TBP), etc.), have been synthesized to form the cationic active species in the presence of alkylaluminum such as Al(i-Bu)_3, AlEt_3, and Al(i-Bu)_2H, which display high activities and distinguishing cis-1,4 selectivities(up to99.9%) for the polymerization of butadiene. The microstructures, yield, molecular weight, and molecular weight distribution of the resulting polymer are well controlled by adjusting electronegativity/steric hindrance of the complexes. In addition, the kinetics, active species, and the possible process of polymerization are also discussed in this article.

关键词： neodymium catalysts Organic sulfonate complexes Tunable electronegativity and steric hindrance Cis-1,4-polymerization Butadiene

Synergistic effects of total ionizing dose and radiated electromagnetic interference on analog-to-digital converter

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nuclear Science and Techniques 2022年第3期33卷 172-180页

作者： Ping Wu Lin Wen Zhi-qian Xu Yun-Sheng Jiang qi Guo cui Meng Department of Engineering Physics Tsinghua UniversityBeijing 100084China Laboratory of Particle and Radiation Imaging Ministry of EducationBeijing 100084China Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of SciencesUrumqi 830011China Key Laboratory of Functional Materials and Devices for Special Environments Urumqi 830011China

The influence of combined total ionization dose(TID)and radiated electromagnetic interference(EMI)in a commercial analog-to-digital converter(ADC)was *** degradation of the direct-current response,the static parameters,and the dynamic parameters caused by the TID and EMI separately and synergistically is *** experimental results demonstrate that the increase in TID intensifies data error and the signal-tonoise ratio(SnR)degradation caused by radiated *** cumulative distribution function of EMI failure with respect to data error and SnR with different TIDs was *** decreasing trend of the threshold was acquired with a small sample size of five for each TID *** result indicates that the ADC is more sensitive in a compound radiation environment.

关键词： Integrated circuit Total ionizing dose Electromagnetic radiation Synergistic effect Combined environment

Fabricating a PVDF skin for PEO-based SPE to stabilize the interface both at cathode and anode for Li-ion batteries

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Journal of Energy Chemistry 2022年第7期31卷 356-362,I0010页

作者： qi Ye Haoyue Liang Shuhao Wang Can.cui Cheng Zeng Tianyou Zhai Huiqiao Li State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina

Poly(ethylene oxide)(PEO)-based solid polymer electrolyte is always the most promising candidate for preparing thinner, lighter and safer lithium-ion batteries. However, the lithium dendrites growth of lithium anode and the high-voltage oxidation of cathode are easy to cause the PEO-based battery *** way to deal with the different challenges on both sides of the anode and cathode is pursued all the time. In this study, we reported a new strategy to construct the PVDF/PEO/PVDF three-layer structure for solid polymer electrolyte(marked as PVDF@PEO) using PVDF as the functional “skin”. The PVDF@PEO electrolyte can effectively prevent from the lithium dendrites, and shows a stable cycling life over1000 h in the Li/PVDF@PEO/Li cell. In addition, the PVDF@PEO electrolyte exhibits higher oxidation resistance and can be matched with high-voltage LiCoO_(2) cathode. The Li/PVDF@PEO/LiCoO_(2) cell delivered a specific capacity of about 150 m Ah g^(-1) over 150 cycles and maintained good cycling stability. Our research provides insights that the polymer electrolytes constructed with PVDF functional “skin” can simultaneously meet the challenges of both anode and cathode in solid-state lithium-ion batteries(SSLIBs).

关键词： PVDF PEO Solid-state lithium-ion batteries Cathode Anode

Three-dimensional modeling and reconstructive change of residual stress during machining process of milling, polishing, heat treatment, vibratory finishing, and shot peening of fan blade

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Advances in Manufacturing 2021年第3期9卷 430-445页

作者： Ji-Yin Zhang Chang-Feng Yao Min-Chao cui Liang Tan Yun-qi Sun Key Laboratory of High Performance Manufacturing for Aero Engine Northwestern Polytechnical UniversityMinistry of Industry and Information TechnologyXi’an710072People’s Republic of China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine Northwestern Polytechnical UniversityMinistry of EducationXi’an710072People’s Republic of China

Residual stress during the machining process has always been a research hotspot,especially for aero-engine *** three-dimensional modeling and reconstructive laws of residual stress among various processes in the machining process of the fan blade is studied in this *** fan blades of Ti-6Al-4V are targeted for milling,polishing,heat treatment,vibratory finishing,and shot *** surface and subsurface residual stress after each process is measured by the X-ray diffraction *** distribution of the surface and subsurface residual stress is *** Rational Taylor surface function and cosine decay function are used to fit the characteristic function of the residual stress distribution,and the empirical formula with high fitting accuracy is *** value and distribution of surface and subsurface residual stress vary greatly due to different processing *** reconstructive change of the surface and subsurface residual stress of the blade in each process intuitively shows the change of the residual stress between the processes,which has a high reference significance for the research on the residual stress of the blade processing and the optimization of the entire blade process.

关键词： Fan blade Machining process Surface residual stress Subsurface residual stress Three-dimensional modeling Reconstructive change