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An Improved Ionospheric Delay Correction Method for SBAS

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Chinese Journal of Electronics 2021年第2期30卷 384-389页

作者： WANG Shan WANG Ding guan Yingxuan China University of Mining and Technology-Beijing

The existing ionospheric delay correction methods in Satellite based augmentation system(SBAS)were just for single constellation and over *** this paper, we propose a new method to make more accurate ionospheric delay correction and tighter error bound orienting towards GPS and GLONASS. Considering that some Ionospheric pierce points(IPPs) are almost motionless, we make a filtering process to estimate the ionospheric delays at Ionospheric grid points(IGPs) to better reflect the ionospheric temporal variation. Then we conduct a simulation on ionospheric delay estimation at IGPs in dual constellations through planar fit method and filtering method. It can be concluded that the filtering method can bound the ionospheric delay correction error more tightly, simultaneously the ionospheric delay correction accuracy is improved a bit.

关键词： simultaneously the ionospheric delay correction accuracy existing ionospheric delay correction methods single constellation satellite navigation ionospheric delay correction error ionospheric temporal variation Global Positioning System ionospheric electromagnetic wave propagation SBAS tighter error bound orienting accurate ionospheric delay correction ionospheric delays ionospheric delay estimation filtering method ionospheric techniques Ionospheric pierce points Ionospheric grid points improved Ionospheric delay correction method Satellite based augmentation system ionosphere planar fit method delays delay estimation

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“一带一路”倡议下实用新型制度的国际协调

科技与法律（中英文） 2025年第1期 91-102页

作者：管荣齐赵旖鑫天津大学法学院天津300110

“一带一路”倡议提出以来已逾十载,我国在这一过程中逐渐具备了规则创新的能力与契机,该种创新可由缺乏国际协调的实用新型制度先行。“一带一路”共建国家以及沿线区域性知识产权组织存在实用新型制度本土化的立法基础、改革经验及协... 详细信息

“一带一路”倡议提出以来已逾十载,我国在这一过程中逐渐具备了规则创新的能力与契机,该种创新可由缺乏国际协调的实用新型制度先行。“一带一路”共建国家以及沿线区域性知识产权组织存在实用新型制度本土化的立法基础、改革经验及协调实践,考虑实用新型制度在保护渐进式创新、维护共建发展中国家利益、提升知识产权国际博弈话语权等方面所发挥的作用,我国应当推行从软法到硬法的实用新型国际协调行动。包括但非限于借助“一带一路”国际合作高峰论坛发起协调倡议、倡导由世界知识产权组织出台《实用新型示范法》、借鉴欧盟的开放协调机制进行规则协商等,并将实用新型制度引入更多双边、多边贸易协定谈判场景。

关键词： “一带一路” 实用新型渐进式创新国际协调发展中国家

Current-Aided Multiple-AUV Cooperative Localization and Target Tracking in Anchor-Free Environments

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IEEE/CAA Journal of Automatica Sinica 2023年第3期10卷 792-806页

作者： Yichen Li Wenbin Yu Xinping guan Department of Automation Shanghai Jiao Tong UniversityShanghai 200240 Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai Jiao Tong UniversityShanghai 200240China IEEE

In anchor-free environments,where no devices with known positions are available,the error growth of autonomous underwater vehicle(AUV)localization and target tracking is unbounded due to the lack of references and the accumulated errors in inertial *** paper aims to improve the localization and tracking accuracy by involving current information as extra *** first integrate current measurements and maps with belief propagation and design a distributed current-aided message-passing scheme that theoretically solves the localization and tracking *** on this scheme,we propose particle-based cooperative localization and target tracking algorithms,named CaCL and CaTT,*** AUV localization,CaCL uses the current measurements to correct the predicted and transmitted position information and alleviates the impact of the accumulated errors in inertial *** target tracking,the current maps are applied in CaTT to modify the position prediction of the target which is calculated through historical *** effectiveness and robustness of the proposed methods are validated through various simulations by comparisons with alternative methods under different trajectories and current conditions.

关键词： Anchor-free belief propagation cooperative localization current-aided target tracking

Homojunction photocatalysts for water splitting

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Nano Research 2022年第12期15卷 10171-10184页

作者： Xiangjiu guan Shichao Zong Shaohua Shen International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi’an Jiaotong UniversityXi’an710049China Suzhou Academy of Xi’an Jiaotong University Suzhou215123China Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region Ministry of EducationSchool of Water and EnvironmentChang’an UniversityXi’an710064China

Charge-carrier separation is regarded as one of the critical issues of photocatalytic water splitting and could be accelerated by constructing microscopic junctions in *** photocatalysts consisting of different forms of semiconductor with identical compositions could inherit the advantages of heterojunction-based photocatalysts in charge separation due to the built-in electric field,while omitting the potential drawbacks of interfacial lattice distortion by providing continuous band ***,homojunction-based photocatalysts have recently drawn growing attention in water *** this review,the synthetic approaches to preparing photocatalysts with various homojunction structures including p-n junction,phase junction,and facet junction were introduced,together with a comprehensive analysis and discussion on the latest progress in the application of photocatalytic water *** review work is expected to inspire more related work with promoted research on designing efficient homojunction-based photocatalytic systems for water splitting.

关键词： photocatalytic water splitting homojunction charge separation

Recent progress and prospect of carbon-free single-site catalysts for the hydrogen and oxygen evolution reactions

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Nano Research 2022年第2期15卷 818-837页

作者： Jingqi guan Xue Bai Tianmi Tang Institute of Physical Chemistry College of ChemistryJilin University2519 Jiefang RoadChangchun 130021China

The key challenge for scalable production of hydrogen from water lies in the rational design and preparation of high-performance and earth-abundant electrocatalysts to replace precious metal Pt and IrO_(2) for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).Although atomic M-N-C materials have been extensively studied in heterogeneous catalysis field,the insufficient antioxidant capacity of carbonous substrates hinders their practical application in *** highly active and stable OER electrocatalysts is the key for electrochemical water *** review presents feasible design strategies for fabricating carbon-free single-site catalysts and their applications in HER/OER and overall water *** constitutive relationships between structure,composition,and catalytic performance for HER and OER are detailly discussed,providing ponderable insights into rationally constructing high-performance HER and OER *** perspectives on the challenges and future research orientations in single-site catalysts for electrochemical water splitting are suggested.

关键词： single-atom catalyst single-site catalyst hydrogen evolution reaction oxygen evolution reaction water splitting

Modeling the Spatial-temporal Characteristics of Mutual Funds’Herd Behavior

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Journal of Systems Science and Systems Engineering 2021年第6期30卷 748-778页

作者： Rong guan Hongjia Chen Shan Lu School of Statistics and Mathematics Central University of Finance and EconomicsBeijing 100081China

Herd behavior in financial markets often leads to unjustified macroscopic ***,despite existing studies on modeling herd behavior,how it varies across individual agents and over time remains *** show that herd behavior in mutual fund companies can be understood from the functional networks representing interactions inferred from investment ***,in this paper,the spatial characteristics of herd behavior stand for the topology relationships of observations in *** analyze the collective dynamics of mutual fund investment from 2003 to 2019 in China using the language of network science and show that herding behavior accompanies this industry's development but dwindles after the 2015 Chinese market *** integrating community detection analysis,we found an increased degree of coherence in the collective herding behavior of the system,even though the localization of herding behavior decreases for clusters of mutual fund companies when the systemic risk builds *** analysis showed that herding behavior impacts the payoff of individual fund companies differently across *** spatial-temporal changes of herding behavior between mutual funds presented in this paper shed light on the debate of individual versus systemic risk and,thus,could interest regulators and investors.

关键词： Mutual funds herding behavior complex network community detection

Self-supported transition metal chalcogenides for oxygen evolution

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Nano Research 2023年第7期16卷 8684-8711页

作者： Ting Zhang Jianrui Sun Jingqi guan Institute of Physical Chemistry College of ChemistryJilin University2519 Jiefang RoadChangchun 130021China School of Chemistry and Life Science Changchun University of TechnologyChangchun 130012China

Owing to stable spatial framework and large electrochemical interface,self-supported transition metal chalcogenides have been actively explored in renewable energy fields,especially in oxygen evolution reaction(OER).Here,we review the research progress of self-supported transition metal chalcogenides(including sulfides,selenides,and tellurides)for the OER in recent *** basic principle and evaluation parameters of OER are first introduced,and then the preparation methods of transition metal chalcogenides on various self-supporting substrates(including Ni foam(NF),carbon cloth(CC),carbon fiber paper(CFP),metal mesh/plate,etc.)are systematically ***,advanced optimization strategies(including interface and defect engineering,heteroatom doping,edge engineering,surface morphology engineering,and construction of heterostructure)are introduced in detail to improve the inherent catalytic activity of self-supported ***,the challenges and prospects of developing more promising self-supported chalcogenide electrocatalysts are proposed.

关键词： self-supported chalcogenide oxygen evolution reaction(OER) interface and defect engineering heteroatom doping heterostructure

On the Interrelation between Spring Bihemispheric Circulations at Middle and High Latitudes

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Advances in Atmospheric Sciences 2019年第12期36卷 1371-1380页

作者： Chuhan LU Zhaoyong guan Key Laboratory of Meteorological Disaster Ministry of Education/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology

Bihemispheric atmospheric interaction and teleconnection allow us to deepen our understanding of large-scale climate and weather variability. This study uses 1979-2017 spring NCEP reanalysis to show that there is interrelation between bihemispheric circulations at the extratropics. This is regarded as a significant negative correlation between the Antarctic and the Arctic regional surface air pressure anomalies, which is induced by interhemispheric oscillation (IHO) of the atmospheric mass. The spatial pattern of IHO is characterized by antiphase extratropical airmass anomalies and geopotential height anomalies from the troposphere to stratosphere between the Southern and Northern Hemisphere. IHO is closely related to stronger bihemispheric low-frequency signals such as Antarctic Oscillation and Arctic Oscillation, thereby demonstrating that IHO can be interpreted as a tie in linking these two dominant extratropical circulations of both hemispheres. IHO is associated with a strong meridional teleconnection in zonal winds from the middle-high troposphere to the lower stratosphere, with the wind anomalies in the form of alternate positive-negative wavy bands extending from the Antarctic to Arctic region, which act as a possible approach to interactions between the bihemispheric atmospheric mass. It is argued that IHO-related omega angular momentum anomalies led by the extratropical atmosphere cause the meridional teleconnection of relative angular momenta, thereby giving rise to the zonal wind anomalies. The modeling of GFDL and UKMO as components of the CMIP5 project have been verified, achieving the related IHO structure shown in the present paper.

关键词： bihemispheric interaction extratropical atmosphere interhemispheric oscillation

Exploration on the stability conditions in bubble columns by noncooperative game theory

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Chinese Journal of Chemical Engineering 2022年第10期50卷 75-84页

作者： Jiachen Liu Xiaoping guan Ning Yang State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

The energy-minimization multiscale(EMMS)model,originally proposed for gas-solid fluidization,features a stability condition to close the simplified conservation *** was put forward to physically reflect the compromise of two dominant mechanisms,i.e.,the particle-dominated with minimal potential energy of particles,and the gas-dominated with the least resistance for gas to penetrate through the particle *** stability condition was then formulated as the minimization of the ratio of these two physical ***,the EMMS approach was later extended to the gas-liquid flow in bubble columns,termed dual-bubble-size *** considers the compromise of two dominant mechanisms,i.e.,the liquid-dominated regime with small bubbles,and the gas-dominated regime with large *** stability condition was then formulated as the minimization of the sum of these two physical ***,the two stability conditions were expressed in different manner,though gas-solid and gas-liquid systems bear some *** addition,both the conditions transform the original multiobjective variational problem into a single-objective *** mathematical formulation of stability condition remains therefore an open *** study utilizes noncooperative game theory and noninferior solutions to directly solve the multi-objective variational problem,aiming to explo re the different pathways of compromise of dominant *** results show that only keeping the single dominant mechanism cannot capture the jump change of gas holdup,which is associated with flow regime *** of dominant mechanisms,noninferior solutions and noncooperative game theory can predict the flow regime ***,the game between the two mechanisms makes the two-bubble structure degenerate and reduce to the single-bubble *** game of the three mechanisms restores the two-bubble *** exploration on the formulation of stability conditions may

关键词： Bubble column Flow regimes Mesoscale Noncooperative gametheory