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Temporal evidence combination method for multi-sensor target recognition based on DS theory and IFS

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Journal of Systems Engineering and Electronics 2017年第6期28卷 1114-1125页

作者： ju wang Fuxian Liu Air and Missile Defense College Air Force Engineering University Xi’an 710051 China

In order to effectively deal with the conflict temporal evidences without affecting the sequential and dynamic characteristics in the multi-sensor target recognition(MSTR) system at the decision making level, this paper proposes a Dempster-Shafer(DS) theory and intuitionistic fuzzy set(IFS) based temporal evidence combination method(DSIFS-TECM). To realize the method,the relationship between DS theory and IFS is firstly analyzed. And then the intuitionistic fuzzy possibility degree of intuitionistic fuzzy value(IFPD-IFV) is defined, and a novel ranking method with isotonicity for IFV is proposed. Finally, a calculation method for relative reliability factor(RRF) is designed based on the proposed ranking method. As a proof of the method, numerical analysis and experimental simulation are performed. The results indicate DSIFS-TECM is capable of dealing with the conflict temporal evidences and sensitive to the changing of time. Furthermore, compared with the existing methods, DSIFS-TECM has stronger ability of anti-interference.

关键词： Dempster-Shafer(DS) theory intuitionistic fuzzy set(IFS) temporal evidence combination relative reliability factor

Vortex Rossby Waves in Asymmetric Basic Flow of Typhoons

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Advances in Atmospheric Sciences 2018年第5期35卷 531-539页

作者： Tianju wang Zhong ZHONG ju wang College of Meteorology and Oceanography National University of Defense Technology Jiangsu Collaborative Innovation Center for Climate Change Nanjing University

Wave ray theory is employed to study features of propagation pathways（rays） of vortex Rossby waves in typhoons with asymmetric basic flow, where the tangential asymmetric basic flow is constructed by superimposing the wavenumber-1 perturbation flow on the symmetric basic flow, and the radial basic flow is derived from the non-divergence equation. Results show that, in a certain distance, the influences of the asymmetry in the basic flow on group velocities and slopes of rays of vortex Rossby waves are mainly concentrated near the radius of maximum wind（RMW）, whereas it decreases outside the RMW. The distributions of radial and tangential group velocities of the vortex Rossby waves in the asymmetric basic flow are closely related to the azimuth location of the maximum speed of the asymmetric basic flow, and the importance of radial and tangential basic flow on the group velocities would change with radius. In addition, the stronger asymmetry in the basic flow always corresponds to faster outward energy propagation of vortex Rossby waves. In short, the group velocities, and thereby the wave energy propagation and vortex Rossby wave ray slope in typhoons, would be changed by the asymmetry of the basic flow.

关键词： asymmetric basic flow vortex Rossby waves group velocity propagation pathways wave ray

Narrow-band interference excision in spread-spectrum systems using new N-sigma algorithm based on fuzzy threshold

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Journal of Systems Engineering and Electronics 2009年第1期20卷 20-26页

作者： Feng Jining Wu Siliang wang ju Dept. of Electronic Engineering Beijing Inst. of Technology Beijing 100081 P. R. China Dept. of Electronic Engineering Hebei Normal Univ. Shijiazhuang 050031 P. R. China

The key to narrow-band interference excision in frequency domain is to determine the excision thresh- old in direct-sequence spread-spectrum （DS-SS） systems. The excision threshold is a non-linear function related to the number and the power of interference, and attempting to get the exact relation of threshold related to the number and the power of interference is almost impossible. The N-sigma algorithm determines the excision threshold using subsection function; however, the excision threshold determined by this method is not exact. A new method to determine the threshold of N-sigma algorithm is proposed. The new method modifies the scale factor N by use of the membership function. The threshold determined by this method is consecutive and smooth, and it is closer to the fact than that of the initial N-sigma algorithm. The GPS signal and single-tone （CW） interference （that is, typical narrow-band interference） are implemented in the simulation, and the results are presented to demonstrate the validity of the new algorithm.

关键词： direct-sequence spread-spectrum systems adaptive frequency domain interference suppression fuzzyfunction GPS signal.

Improved direct P code acquisition technique

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Journal of Systems Engineering and Electronics 2009年第5期20卷 948-953页

作者： Xu Ying wang ju Wu Siliang Academy of Opto-Electronics Chinese Academy of Science Beijing 100190 P. R. China School of Information Science and Technology Beijing Inst. of Technology Beijing 100081 P. R. China

P code direct acquisition is an important technology in satellite navigation system. As the P code has a long period, it is hard to directly acquire. The traditional average method can process multiple code phases in a time to shorten the acquisition time. But with the increase of average phase error of the input signal and the local code, the correlation signal-to-noise ratio （SNR） loss increases. To reduce the SNR loss, an improved average method is introduced. A new sequence is generated with a summation of phase shifting sequences to decrease correlation peak loss. Simulation results show that compared with direct average method, the improved average method effectively increases correlation SNR.

关键词： P code acquisition direct average algorithm improved average algorithm.

On area-specific underground research laboratory for geological disposal of high-level radioactive waste in China

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第2期6卷 99-104页

作者： ju wang Beijing Research Institute of Uranium Geology(BRIUG) China National Nuclear Corporation(CNNC)

Underground research laboratories （URLs）, including ＂generic URLs＂ and ＂site-specific URLs＂, are un- derground facilities in which characterisation, testing, technology development, and/or demonstration activities are carried out in support of the development of geological repositories for high-level radioactive waste （HLW） disposal. In addition to the generic URL and site-specific URL, a concept of ＂areaspecific URL＂, or the third type of URL, is proposed in this paper. It is referred to as the facility that is built at a site within an area that is considered as a potential area for HLW repository or built at a place near the future repository site, and may be regarded as a precursor to the development of a repository at the site. It acts as a ＂generic URL＂, but also acts as a ＂site-specific URL＂ to some extent. Considering the current situation in China, the most suitable option is to build an ＂area-specific URL＂ in Beishan area, the first priority region for China＇s high-level waste repository. With this strategy, the goal to build China＇s URL by 2020 mav be achieved, but the time left is limited.

关键词： Underground research laboratory (URL)Area-specific URL High-level radioactive waste (HLW)Geological disposal

Agglomeration Mechanism of Rich Hematite Sinter with Lowering SiO_2 Content

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 256-260页

作者： Duan, Dongping Gong, Yibo wang, ju Metallurgy School University of Science and Technology Beijing Beijing 100083 China High Technology and Research Development Center Ministry of Science and Technology Beijing 100862 China

The mini-sintering test was introduced. The experiments of specimens of rich hematite with lowering SiO2 content were carried out by the mini-sintering test. The strength and mechanism of agglomeration were studied mainly when silica content in sintered specimens was decreased gradually. The relationships between SiO2 volume and morphology of sinter were also investigated. It is considered that high grade sinter can be developed by raising sinter basicity so as to enhance complex calcium ferrite content or lowering sinter basicity so as to make Fe2O3 bonding for strength.

关键词： SiO Rich Agglomeration Mechanism of Rich Hematite Sinter with Lowering SiO2 Content

A Comparative Study of Fractional Order Models on State of Charge Estimation for Lithium Ion Batteries

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Chinese Journal of Mechanical Engineering 2020年第4期33卷 98-112页

作者： Jinpeng Tian Rui Xiong Weixiang Shen ju wang Department of Vehicle Engineering School of Mechanical EngineeringBeijing Institute of TechnologyBeijing 100081China Faculty of Science Engineering and TechnologySwinburne University of TechnologyHawthornVictoria 3122Australia

State of charge(SOC)estimation for lithium ion batteries plays a critical role in battery management systems for electric *** fractional order models(FOMs)which come from frequency-domain modelling have provided a distinct insight into SOC *** this article,we compare five state-of-the-art FOMs in terms of SOC *** this end,firstly,characterisation tests on lithium ion batteries are conducted,and the experimental results are used to identify FOM *** identification results show that increasing the complexity of FOMs cannot always improve *** model R(RQ)W shows superior identification accuracy than the other four ***,the SOC estimation based on a fractional order unscented Kalman filter is conducted to compare model accuracy and computational burden under different profiles,memory lengths,ambient temperatures,cells and voltage/current *** evaluation results reveal that the SOC estimation accuracy does not necessarily positively correlate to the complexity of *** more complex models can have better robustness against temperature variation,R(RQ),the simplest FOM,can overall provide satisfactory *** results on different cells demonstrate the generalisation ability of FOMs,and R(RQ)outperforms other ***,R(RQ)shows better robustness against truncation error and can maintain high accuracy even under the occurrence of current or voltage sensor drift.

关键词： Electric vehicle Lithium ion battery Fractional order model State of charge

Investigation and analysis of negative emotion in patients with diabetic retinopathy after vitrectomy

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World Journal of Psychiatry 2024年第10期14卷 1513-1520页

作者： Zhi-Heng ju Mei-ju wang Department of Ophthalmology The Third People’s Hospital of ChangzhouChangzhou 213001Jiangsu ProvinceChina

BACKGROUND As the incidence of diabetes continues to increase,the number of patients with diabetic retinopathy(DR)also increases each *** undergoing vitrectomy for DR,patients often experience negative emotional problems that negatively affect their *** To investigate negative feelings in patients with DR after vitrectomy and to explore related influencing *** A total of 146 individuals with DR who were accepted for treatment at The Third People’s Hospital of Changzhou from May 2021 to April 2023 were recruited to participate in this *** patients underwent *** self-rating anxiety scale(SAS)and self-rating depression scale(SDS)were used to assess the degree of anxiety and depression 2-3 days after the *** participants were divided into a healthy control group and a negative emotion *** patients’general demographic characteristics and blood glucose levels were *** regression analysis was used to analyze the factors influencing negative feelings ***’s correlation coefficient was used to analyze the association between SAS scores,SDS scores,and blood glucose *** The control group included 85 *** negative emotion group comprised 40 participants with anxiety,13 with depression,and eight with *** regression showed that being female(OR=3.090,95%CI:1.217-7.847),a family per capita monthly income of<5000 yuan(OR=0.337,95%CI:0.165-0.668),and a longer duration of diabetes(OR=2.068,95%CI:1.817-3.744)were risk factors for negative emotions in patients with DR after vitrectomy(P<0.05).The concentrations of fasting plasma glucose(FPG),2-hour postprandial glucose(2hPG),and glycated hemoglobin(HbA1c)in the negative emotion group exceeded those in the control group(P<0.05).SAS scores were positively associated with FPG(r=0.422),2hPG(r=0.334),and HbA1c(r=0.362;P<0.05).SDS scores were positively correlated with FPG(r=0.218)and 2hPG(r=0.218;P<0.05).CONCLUSION S

关键词： Diabetic retinopathy Vitrectomy Anxiety Depression Blood glucose levels Risk factors

Crystal structure of β-cyclodextrin-4-chlorobenzoic acid complex:Unusual C-Cl…π interaction between 4-chlorobenzoic acids in β-cyclodextrin dimer

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Chinese Chemical Letters 2011年第7期22卷 847-850页

作者： En ju wang Guang Ying Chen Hainan Provincial Key Laboratory of Tropical Pharmaceutical Herb Chemistry School of Chemistry & Chemical Engineering Hainan Normal University Haikou 571158 China

The inclusion complex of β-cyclodextrin （β-CD） with 4-chlorobenzoic acid was synthesized and its crystal structure was determined by single crystal X-ray diffraction under cryogenic condition. The complex contains two β-CDs, two 4-chlorobenzoic acids and twenty-nine water molecules in the asymmetric unit, and can be formulated as 2（C42H70O35）·2（CTH5O2Cl）·29（H2O）. In the crystal lattice, two β-CDs form a face-to-face dimer jointed together through hydrogen bonding between the secondary hydroxyl groups of β--CDs. Two 4-chlorobenzoic acid molecules which contact by C-Cl…π interactions are included in the β-CD dimer cavity. The β-CD dimers are arranged in brickwork-like pattern along the crystallographic a-axis. The effect of guest molecule length on the inclusion geometry was discussed by comparative study of some fl-CD complexes containing similar guests.

关键词： β-Cyclodextrin 4-Chlorobenzoic acid Inclusion complex Crystal structure C-Cl…π interaction