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A Multi-Vehicle Cooperative Localization Method Based on Belief Propagation in Satellite Denied Environment

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Journal of Beijing Institute of Technology 2022年第5期31卷 464-472页

作者： jiaqi wang Lina wang School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China

The global navigation satellite system(GNSS)is currently being used extensively in the navigation system of ***,the GNSS signal will be faded or blocked in complex road environments,which will lead to a decrease in positioning *** to the higher-precision synchronization provided in the sixth generation(6G)network,the errors of ranging-based positioning technologies can be effectively *** the same time,the use of terahertz in 6G allows excellent resolution of range and angle,which offers unique opportunities for multi-vehicle cooperative localization in a GNSS denied *** paper introduces a multi-vehicle cooperative localization *** the proposed method,the location estimations of vehicles are derived by utilizing inertial measurement and then corrected by exchanging the beliefs with adjacent vehicles and roadside *** multi-vehicle cooperative localization problem is represented using a factor *** iterative algorithm based on belief propagation is applied to perform the inference over the factor *** results demonstrate that our proposed method can offer a considerable capability enhancement on localization accuracy.

关键词： cooperative localization belief propagation factor graph inertial navigation system internet of vehicles

Photodetection-induced relative timing jitter in synchronized time-lens source for coherent Raman scattering microscopy

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Journal of Innovative Optical Health Sciences 2017年第5期10卷 69-76页

作者： jiaqi wang Ping Qiu Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Optoelectronic Engineering Shenzhen University Shenzhen 518060 China College of Physics and Energy Shenzhen University Shenzhen 518060 China

Synchronized time lens source is a novel method to generate synchronized optical pulses to mode-locked lasers,and has found widespread applications in coberent Raman scattering *** timing jitter between the mode-locked laser and the synchronized time-lens source is a key parameter for evaluating the synchronization peformance of such synchronized laser ***,the origins of the relative timing jitter in such systens are not fully determined,which in turn prevents the experimental efforts to optimize the synchronization ***,we demonstrate,through theoretical modeling and mumerical simulation,that the photo-detction could be one physical origin of the relative timing *** with relative timing jitter due to the intrinsic timing jitter of the mode-locked laser is also demonstrated,revealing different qualitative and quantitative *** on the nature of this photo-detection-induced timing jitter,we further propose several strategies to reduce the relative timing *** thoretical results will provide guidelines for optimizing synchronization performance in experiments.

关键词： Synchronized time-lens source coherent Raman sca tering microscopy

Direct and rapid detection of serum amino acid and monoamine neurotransmitters to assist the diagnosis of panic disorder

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Science China Chemistry 2025年第1期 377-384页

作者： Shiwen Liu Xuerui Wan Meng Zhao jiaqi wang Weilan Wu Linlin You Yonggui Yuan Qian Xu Rong Gao Key Laboratory of Environmental Medicine Engineering Ministry of Education School of Public Health Southeast University Key Laboratory of Modern Toxicology of Ministry of Education Department of Hygienic Analysis and Detection School of Public HealthNanjing Medical University Department of Psychosomatics and Psychiatry Zhongda Hospital School of Medicine Southeast University

The measurement of amino acid and monoamine neurotransmitters（NTs） in serum plays a central role in the identification and monitoring of clinical panic disorder（PD）. However, the strong polarity and chemical heterogeneity of NTs make direct extraction and rapid detection extremely challenging. Herein, we developed a strategy that integrated solid phase extraction based on magnetic Fe3O4coated with polydopamine（Fe3O4@PDA） and direct analysis of mass spectrometry in real time（DART-MS） for quantification of 10 NTs. We systematically investigated the optimal conditions of this strategy to achieve good accuracy and precision. Compared with existing magnetic solid phase extraction methods for NTs detection in biological samples, this strategy could adsorb more targets while having similar adsorption efficiencies, and the total process time was reduced by an average of 69.42%. We rapidly determined the metabolic abnormality of 6 types of NTs in the serum of PD patients and demonstrated their diagnostic accuracy. In addition, an outstanding feature of PD in which tryptophan was more metabolized by the KYN pathway and the 5-hydroxytryptamine pathway was inhibited could be elucidated by this strategy. Our results highlighted the potential ability of Fe3O4@PDA coupled with DART-MS to assist in the clinical diagnosis of PD.

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Control of fine particulate nitrate during severe winter haze in“2+26”cities

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Journal of Environmental Sciences 2024年第2期136卷 261-269页

作者： Chuang Qin Xiao Fu Tao wang Jian Gao jiaqi wang Institute of Environment and Ecology Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Department of Civil and Environmental Engineering Hong Kong Polytechnic UniversityHong Kong 99907China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 10084China

The“2+26”cities,suffering the most severe winter haze pollution,have been the key region for air quality improvement in *** prominent nitrate pollution is one of the most challenging environmental issues in this region,necessitating development of an effective control ***,we use observations,and state-of-the-art model simulations with scenario analysis and process analysis to quantify the effectiveness of the future SO_(2)-NO_(X)-VOC-NH_(3) emission control on nitrate pollution mitigation in“2+26”*** on a serious winter haze episode,we find that limited NO_(X)emission reduction alone in the short-term period is a less effective choice than VOC or NH_3emission reduction alone to decrease nitrate concentrations,due to the accelerated NO_(X)-HNO_(3)conversion by atmospheric oxidants and the enhanced HNO_(3)to NO_(3)^(-)partition by ammonia,although deep NO_(X)emission reduction is essential in the long-term *** synergistic NH_(3) and VOC emission control is strongly recommended,which can counteract the adverse effects of nonlinear photochemistry and aerosol chemical feedback to decrease nitrate *** extra benefits will be reduced if the synergistic NH_(3) and VOC reduction is delayed,and thus reducing emission of multiple precursors is urgently required for the effective control of increasingly severe winter nitrate pollution in“2+26”cities.

关键词： Nitrate Winter haze pollution Emission reduction “2+26”cities

Modelling the formation and dissolution behavior of alumina agglomerate in the cryolite

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Particuology 2024年第3期86卷 211-222页

作者： jiaqi wang Mao Li Benjun Cheng Hesong Li School of Energy Science and Engineering Central South UniversityChangsha410083China

The presence of alumina agglomerates seriously affects the current efficiency of the aluminum electrolysis *** the dynamic dissolution process of agglomerates is essential to improve the current efficiency of aluminum electrolysis.A mathematical model is proposed to describe the different phenomena from the formation until complete dissolution of *** permeation and solidification processes of cryolite,a semi-analytical mathematical model is developed to formulate the formation,melting and dissolution processes of agglomerates,and the time duration for each stage is *** and heat mass transfer of agglomerates are explored based on the packing theory and mechanism of heat mass transfer in wet porous *** approach is applied to investigate the main factors affecting the dissolution stages and porosity of *** results show that the superheat has a great influence on the formation and melting stage,the diameter of agglomerates can reach 14.93 mm for 200 particles *** density decreases with the increase of agglomerated particle number,which varies in the range of 2.27-2.28 g/cm^(3).The average dissolution rate of agglomerates is about 1.83×10^(-5)-2.95×10^(-5) kg/s within the range of alumina concentration in this study.

关键词： Mathematical model Alumina agglomerate Porous media Packing theory Heatand mass transfer

On the existence and regularity of vector solutions for quasilinear systems with linear coupling

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Science China Mathematics 2019年第1期62卷 125-146页

作者： Yong Ao jiaqi wang Wenming Zou Department of Mathematical Sciences Tsinghua University

We study the following coupled system of quasilinear equations:Under some assumptions on the nonlinear terms f and g, we establish some results about the existence and regularitl of vector solutions for the p-Laplacian systems by using variational methods. In particular, we get two pairs of nontrivial solutions. We also study the different asymptotic behavior of solutions as the coupling parameter λ tends to zero.

关键词： p-Laplacian system least energy solutions Moser iteration variational methods

Urea transport and hydrolysis in the rumen: A review

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Animal Nutrition 2021年第4期7卷 989-996页

作者： Samson Hailemariam Shengguo Zhao Yue He jiaqi wang State Key Laboratory of Animal Nutrition Institute of Animal SciencesChinese Academy of Agricultural SciencesBeijing100193China Dilla University College of Agriculture and Natural ResourceDilla P.O.Box 419Ethiopia

Inefficient dietary nitrogen(N)conversion to microbial proteins,and the subsequent use by ruminants,is a major research focus across different *** bacterial ammonia(NH3)produced due to degradation or hydrolyses of N containing compounds,such as urea,leads to an inefficiency in a host’s ability to utilize *** is a non-protein N containing compound used by ruminants as an ammonia source,obtained from feed and endogenous *** is hydrolyzed by ureases from rumen bacteria to produce NH_(3) which is used for microbial protein ***,lack of information exists regarding urea hydrolysis in ruminal bacteria,and how urea gets to hydrolysis ***,this review describes research on sites of urea hydrolysis,urea transport routes towards these sites,the role and structure of urea transporters in rumen epithelium and bacteria,the composition of ruminal ureolytic bacteria,mechanisms behind urea hydrolysis by bacterial ureases,and factors influencing urea *** review explores the current knowledge on the structure and physiological role of urea transport and ureolytic bacteria,for the regulation of urea hydrolysis and recycling in ***,underlying mechanisms of urea transportation in rumen bacteria and their physiological importance are currently unknown,and therefore future research should be directed to this subject.

关键词： Urea transporter Urea Urea hydrolysis Ruminal bacteria

Numerical simulation on magnetic confinement characteristics of internal vortex electrostatic cyclone precipitator under different working voltages

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Particuology 2023年第3期74卷 156-163页

作者： Jianping Zhang jiaqi wang Peng Che Youqi wang Zhiyao Lu Zibing Qu School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghaiChina College of Energy and Mechanical Engineering Shanghai University of Electric PowerShanghaiChina Sino-German College University of Shanghai for Science and TechnologyShanghaiChina

Aiming at improving the capture performance of internal vortex electrostatic cyclone precipitator(ECP),a theoretical model with mechanics-electric-magnetic coupling was established,the collection efficiency of magnetic confinement ECP under different working voltages was simulated,and the influence of magnetic flux intensity on the removal performance of submicron particles was *** show that the number of particles escaped from the cyclone is greatly reduced after the introduction of magnetic field and electric field,indicating that charging effect and magnetic confinement are more conductive to trap submicron particles in the internal vortex *** lower the working voltage is,the worse the charging lifting effect is,but the stronger the magnetic confinement characteristics ***,the contributions of charging effect to collection efficiency and magnetic confinement characteristics are more obvious at a weaker magnetic flux *** research results can provide a practical new idea for the innovative design of ECP.

关键词： Magnetic confinement characteristics Working voltage Internal vortex ECP Submicron particles Capture performance

Siamese transformer with hierarchical concept embedding for fine-grained image recognition

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Science China(Information Sciences) 2023年第3期66卷 188-203页

作者： Yilin LYU Liping JING jiaqi wang Mingzhe GUO Xinyue wang Jian YU School of Computer and Information Technology Beijing Jiaotong University Beijing Key Lab of Traffic Data Analysis and Mining Beijing Jiaotong University Alibaba Group

Distinguishing the subtle differences among fine-grained images from subordinate concepts of a concept hierarchy is a challenging task. In this paper, we propose a Siamese transformer with hierarchical concept embedding(STr HCE), which contains two transformer subnetworks sharing all configurations,and each subnetwork is equipped with the hierarchical semantic information at different concept levels for fine-grained image embeddings. In particular, one subnetwork is for coarse-scale patches to learn the discriminative regions with the aid of the innate multi-head self-attention mechanism of the transformer. The other subnetwork is for finer-scale patches, which are adaptively sampled from the discriminative regions, to capture subtle yet discriminative visual cues and eliminate redundant information. STr HCE connects the two subnetworks through a score margin adjustor to enforce the most discriminative regions generating more confident predictions. Extensive experiments conducted on four commonly-used benchmark datasets, including CUB-200-2011, FGVC-Aircraft, Stanford Dogs, and NABirds, empirically demonstrate the superiority of the proposed STr HCE over state-of-the-art baselines.

关键词： fine-grained image recognition transformer hierarchical concept embedding adaptive sampling Siamese network