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Estimation of Vehicle Pose and Position with Monocular Camera at Urban Road Intersections

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Journal of Computer Science & Technology 2017年第6期32卷 1150-1161页

作者： jin-zhao yuan Hui Chen Bin zhao Yanyan Xu School of Information Science and Engineering Shandong University Jinan 250100 China Beijing Xuanlongding-xun Technology Co. Ltd. Beijing 100041 China Department of Civil and Environmental Engineering Massachusetts Institute of Technology Cambridge 02139 U.S.A.

With the rapid development of urban, the scale of the city is expanding day by day. The road environment is becoming more and more complicated. The vehicle ego-localization in complex road environment puts forward imperative requirements for intelligent driving technology. The reliable vehicle ego-localization, including the lane recognition and the vehicle position and attitude estimation, at the complex traffic intersection is significant for the intelligent driving of the vehicle. In this article, we focus on the complex road environment of the city, and propose a pose and position estimation method based on the road sign using only a monocular camera and a common GPS （global positioning system）. Associated with the multi-sensor cascade system, this method can be a stable and reliable alternative when the precision of multi-sensor cascade system decreases. The experimental results show that, within 100 meters distance to the road signs, the pose error is less than 2 degrees, and the position error is less than one meter, which can reach the lane-level positioning accuracy. Through the comparison with the Beidou high-precision positioning system L202, our method is more accurate for detecting which lane the vehicle is driving on.

关键词： vehicle pose and position estimation road sign detection homograph matrix road intersection urban envi-ronment

A strange phenomenon in XZ Andromedae: two Keplerian periods with a 1:3 ratio

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Research in Astronomy and Astrophysics 2019年第9期19卷 63-70页

作者： jin-zhao yuan Sheng-Bang Qian Department of Physics Shanxi Normal UniversityLinfen041004China Yunnan Observatories Chinese Academy of SciencesKunming650011China

Six mid-eclipse times of the eclipsing binary XZ And are obtained, which are analyzed together with others collected from the literature. Two sets of cyclic variations with periods of 33.43 and 100.4 yr are found if a double-Keplerian model is used to fit the data. The 1:3 ratio of the periods suggests that both cyclic variations arise from dynamic motions of two companions rather than magnetic activity of the eclipsing pair. According to the double-Keplerian model, the companions have masses of^1.32 M_⊙and^1.33 M_⊙, respectively. Comparing with the total mass of the eclipsing pair of 3.12 M_⊙, it is obvious that XZ And is a general N-body system. The strong gravitational perturbation between the two companions invalidates the double-Keplerian model. It is strange that two Keplerian periods with a 1:3 ratio are derived from the best fits with an 'inappropriate' model. This illogical, but interesting phenomenon also appears in two other Algol systems, suggesting that our discoveries deserve attention from astronomers.

关键词： binaries:close stars:individual:XZ Andromedae

Z Draconis with two companions in a 2:1 mean-motion resonance

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Research in Astronomy and Astrophysics 2016年第5期16卷 99-108页

作者： jin-zhao yuan Hakan Volkan Senavc? Sheng-Bang Qian Department of Physics Shanxi Normal University Department of Astronomy and Space Sciences Ankara University Faculty of Science Yunnan Observatories Chinese Academy of Sciences

All available mid-eclipse times of the eclipsing binary Z Draconis are analyzed, and three sets of cyclic variations with periods of 20.1, 29.96 and 59.88 yr are found. The low-amplitude variations with a period of 20.1 yr may be attributed to the unavoidable slight imperfection in the double-Keplerian model, which gives periods of 29.96 and 59.88 yr. Interestingly, the Z Draconis system is close to a 2：1 mean- motion resonance, or a 6：3：2 mean-motion resonance if the 20.1 yr period really exists. We also find that the best solutions tend to give the minimum eccentricities. Based on Kepler＇s third law, the outermost companion has a minimum mass of - 0.77 Mo, whereas the middle companion is an M dwarf star with a mass of - 0.40 MG, suggesting that Z Draconis is a general N-body system.

关键词： binaries: close -- stars: individual (Z Draconis) -- methods: numerical

First photometric study of the eclipsing binary PS Persei

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Research in Astronomy and Astrophysics 2011年第2期11卷 191-197页

作者： jin-zhao yuan Physics and Information Engineering Institute,Shanxi Normal University,Linfen 041004,China Physics and Information Engineering Institute Shanxi Normal University Linfen 041004 China

CCD photometric observations of the eclipsing binary PS Persei （PS Per） were obtained on two consecutive days in *** 2003 version of the WilsonDevinney code was used to analyze the first complete light curves in the V and R *** is found that PS Per is a short-period Algol-type binary with the less massive component completely filling its inner critical Roche *** mass ratio of q=0.518 and the orbital inclination of i=89.86° are *** addition,based on all available times of primary light minima,including two new ones,the orbital period has been improved.

关键词： stars: binaries: close -- stars: binaries: eclipsing -- stars: individual:PS Per

A Photometric Study of the Near Contact Binary UU Lyncis

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Chinese Journal of Astronomy and Astrophysics 2007年第2期7卷 251-257页

作者： Li-Ying Zhu Sheng-Bang Qian 1,2 Soonthomthum Boonrucksar Jia-JiaHe jin-zhao yuan National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming650011 United Laboratory of Optical Astronomy Chinese Academy of Sciences （ULOAC）. 100012 Beijing Graduate School of Chinese Academy of Sciences ＂ Beijing 100049 Department of Physics Faculty of Science Chiang Mai University Chiang Mai 50200 Thailand

The near-contact binary UU Lyn with an F3V-type primary was observed in 2005 and 2006. With the latest version of the Wilson-Devinney code, the photometric elements were computed. The results reveal that UU Lyn is a marginal contact system with a large temperature difference of about 1900 K between the primary and secondary components. All available eclipse times, including new ones, were used in the analysis. The results show that the orbital period of this system undergoes a continuous decrease at a rate of dP/dt = -1.84 × 10^-8 d yr^-1. With the period decrease, UU Lyn may evolve from the present shortperiod marginal contact system into a contact system with true thermal contact. This target might just be undergoing the cycles predicted by the theory of thermal relaxation oscillations （TRO）. It is an interesting example resembling BL And, GW Tau, ZZ Aur, KQ Gem, CN And and AD Cnc, that lie in the key evolutionary stage.

关键词： techniques photometric- binaries eclipsing - stars individual UU Lyncis

A Deep Learning Estimation Method for Temperature-Induced Girder End Displacements of Suspension Bridges

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Structural Durability & Health Monitoring 2025年第2期19卷 307-325页

作者： Yao jin yuan Ren Chong-yuan Guo Chong Li zhao-yuan Guo Xiang Xu School of Transportation Southeast UniversityNanjing210096China Department of Engineering Guangzhou Expressway Operation Management Co.Ltd.Guangzhou510000China Department of Engineering CCCC Highway Bridge National Engineering Research Center Co.Ltd.Beijing100088China Department of Engineering Jiangsu Provincial Transportation Engineering Construction BureauNanjing210004China

To improve the accuracy of thermal response estimation and overcome the limitations of the linear regression model and Artificial Neural Network(ANN)model,this study introduces a deep learning estimation method specifically based on the Long Short-Term Memory(LSTM)network,to predict temperature-induced girder end displacements of the Dasha Waterway Bridge,a suspension bridge in ***,to enhance data quality and select target sensors,preprocessing based on the sigma rule and nearest neighbor interpolation is applied to the raw ***,to eliminate the high-frequency components from the displacement signal,the wavelet transform is ***,the linear regression model and ANN model are established,whose results do not meet the requirements and fail to address the time lag effect between temperature and *** study proceeds to develop the LSTM network model and determine the optimal parameters through hyperparameter sensitivity ***,the results of the LSTM network model are discussed by a comparative analysis against the linear regression model and ANN model,which indicates a higher accuracy in predicting temperatureinduced girder end displacements and the ability to mitigate the time-lag *** be more specific,in comparison between the linear regression model and LSTM network,the mean square error decreases from 6.5937 to 1.6808 and R2 increases from 0.683 to 0.930,which corresponds to a 74.51%decrease in MSE and a 36.14%improvement in *** to ANN,with an MSE of 4.6371 and an R2 of 0.807,LSTM shows a decrease in MSE of 63.75%and an increase in R2 of 13.23%,demonstrating a significant enhancement in predictive performance.

关键词： Suspension bridges thermal response girder end displacement deep learning

Machine learning for online control of particle accelerators

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 94-104页

作者： Xiaolong Chen Zhijun Wang yuan He Hong zhao Chunguang Su Shuhui Liu Weilong Chen Xiaoying zhao Xin Qi Kunxiang Sun Chao jin Yimeng Chu Hongwei zhao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Advanced Energy Science and Technonlogy Guangdong Laboratory Huizhou 516000China Department of Physics Xiamen UniversityXiamen 361005China

Particle accelerators play a critical role in modern scientific ***,existing manual beam control methods heavily rely on experienced operators,leading to significant time consumption and potential challenges in managing next-generation accelerators characterized by higher beam current and stronger nonlinear *** this paper,we establish a dynamical foundation for designing the online adaptive controller of accelerators using machine *** provides a guarantee for dynamic controllability for a class of scientific instruments whose dynamics are described by spatial-temporal equations of motion but only part variables along the instruments under steady states are *** necessity of using historical time series of beam diagnostic data is *** strategies involve also employing a well-established virtual beamline of accelerators,by which various beam calibration scenarios that actual accelerators may encounter are *** the reinforcement learning algorithm is adopted to train the controller with the interaction to the virtual ***,the controller is seamlessly transitioned to real ion accelerators,enabling efficient online adaptive control and ***,the controller demonstrates significant robustness,effectively managing beams with diverse charge mass ratios without requiring *** a controller allows us to achieve the global control within the entire superconducting section of the China Accelerator Facility for Superheavy Elements.

关键词： nonlinear complex system adaptive control machine learning particle accelerator simulation to reality

Utilizing BP neural networks to accurately reconstruct the tritium depth profile in materials for BIXS

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Nuclear Science and Techniques 2025年第1期36卷 103-114页

作者： Chen zhao Wei jin Yan Shi Chang-An Chen Yi-Ying zhao Institute of Materials China Academy of Engineering PhysicsJiangyou 621908China

β-ray-induced X-ray spectroscopy(BIXS)is a promising method for tritium detection in solid materials because of its unique advantages,such as large detection depth,nondestructive testing capabilities,and low requirements for sample ***,high-accuracy reconstruction of the tritium depth profile remains a significant challenge for this *** this study,a novel reconstruction method based on a backpropagation(BP)neural network algorithm that demonstrates high accuracy,broad applicability,and robust noise resistance is *** average reconstruction error calculated using the BP network(8.0%)was much lower than that obtained using traditional numerical methods(26.5%).In addition,the BP method can accurately reconstruct BIX spectra of samples with an unknown range of tritium and exhibits wide applicability to spectra with various tritium ***,the BP network demonstrates superior accuracy and stability compared to numerical methods when reconstructing the spectra,with a relative uncertainty ranging from 0 to 10%.This study highlights the advantages of BP networks in accurately reconstructing the tritium depth profile from BIXS and promotes their further application in tritium detection.

关键词： β-ray-induced X-ray spectroscopy Tritium detection BP network Ridge regression Reconstruction problem

Molsidomine and N-omega-nitro-L-arginine methyl ester inhibit implantation and apoptosis in mouse endometrium

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Acta Pharmacologica Sinica 2003年第12期24卷 3-10页

作者： WEI Peng, yuan jin-Xiang, jin Xuan, HU zhao-yuan, LIU Yi-Xur State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080, China Institute of Zoology Chinese Academy of Sciences State Key Laboratory of Reproductive Biology 北京 100080

AIM: To investigate the possible effect of nitric oxide on receptivity and apoptosis of mouse endometrium and the possible pathway. METHODS: Female pregnant mice were treated with either molsidomine, a generator of nitric oxide (NO), or N-omega-nitro-L-arginine methyl ester (L-NAME), an inhibitor of NO synthase. The pregnancy rates of each group were calculated; 3’-end-labeling was used to detect DNA fragmention of apoptotic cells; immunohistochemistry, in situ hybridization, and Western blot were applied respectively to estimate expression levels of Fas/FasL proteins and mRNA. RESULTS: The pregnancy rate in the drug treated group was reduced in a dose-dependent manner; apoptosis, Fas protein and mRNA levels in the endometrium of drug treated mice were correlatively decreased during the peri-implantation period. CONCLUSION: The decreased pregnant rate in mice by abnormal levels of nitric oxide may be brought about by inhibiting the normally occurrence of apoptosis in the receptive endometrium.

关键词： nitric oxide apoptosis pregnancy rate endometrium