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Bright soliton dynamics for resonant nonlinear Schrödinger equation with generalized cubic-quintic nonlinearity

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CHINESE PHYSICS B 2024年第12期33卷 278-288页

作者： Bao, Keyu tang, xiaogang Wang, Ying Jiangsu Univ Sci & Technol Sch Sci Jiangsu 212100 Zhenjiang Peoples R China

For systems modeled by the resonant nonlinear Schr & ouml;dinger equation (RNLSE) with generalized cubic-quintic nonlinearity, we derive the bright soliton solution of the equation in (1+1) dimensions, using the modified F-expansion method along with the novel ansatz of F-base function. Furthermore, we extend the analytical study of soliton dynamics to higher (2+1) and (3+1) dimensions by using the self-similar method, and demonstrate the soliton behavior via graphical illustration. Moreover, we investigate the effect of the resonance term on bright soliton solution in (1+1) dimensions. Additionally, we consider the nonlinear equation models with perturbation terms and derive the bright soliton solutions for the one-dimensional (1D) to three-dimensional (3D) cases. The theoretical results derived can be used to guide the experimental studies and observations of bright solitons in systems described by RNLSE model.

关键词： soliton resonant nonlinear Schr & ouml dinger equation F-expansion method 42.65.Tg 42.81.Dp 02.30.Jr 42.50.Md

A Residual Frequency Offset Estimation Method Based on Range Migration Fitting

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Journal of Beijing Institute of Technology 2024年第2期33卷 103-110页

作者： Liting Zhang Hao Huan Ran Tao xiaogang tang School of Information and Electronics Beijing Institute of Technology School of Aerospace Information Space Engineering University

Recently, researchers have proposed an emitter localization method based on passive synthetic aperture. However, the unknown residual frequency offset(RFO) between the transmitter and the receiver causes the received Doppler signal to shift, which affects the localization accuracy. To solve this issue, this paper proposes a RFO estimation method based on range migration fitting. Due to the high frequency modulation slope of the linear frequency modulation(LFM)-modulation radar signal, it is not affected by RFO in range compression. Therefore, the azimuth time can be estimated by fitting the peak value position of the pulse compression in range ***, the matched filters are designed under different RFOs. When the zero-Doppler time obtained by the matched filters is consistent with the estimated azimuth time, the given RFO is the real RFO between the transceivers. The simulation results show that the estimation error of azimuth distance does not exceed 20 m when the received signal duration is not less than 3 s, the pulse repetition frequency(PRF) of the transmitter radar signal is not less than 1 k Hz, the range detection is not larger than 1 000 km, and the signal noise ratio(SNR) is not less than –5 d B.

关键词： range migration fitting (RMF) passive localization residual frequency offset (RFO)

Radio Frequency Fingerprint-Based Satellite TT&C Ground Station Identification Method

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Journal of Beijing Institute of Technology 2023年第1期32卷 1-12页

作者： xiaogang tang Junhao Feng Binquan Zhang Hao Huan School of Aerospace Information Space Engineering UniversityBeijing 101407China School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

This study presents a radio frequency(RF)fingerprint identification method combining a convolutional neural network(CNN)and gated recurrent unit(GRU)network to identify measurement and control *** proposed algorithm(CNN-GRU)uses a convolutional layer to extract the IQ-related learning timing features.A GRU network extracts timing features at a deeper level before outputting the final identification *** number of parameters and the algorithm’s complexity are reduced by optimizing the convolutional layer structure and replacing multiple fully-connected layers with gated cyclic *** experiments show that the algorithm achieves an average identification accuracy of 84.74% at a -10 dB to 20 dB signal-to-noise ratio(SNR)with fewer parameters and less computation than a network model with the same identification rate in a software radio dataset containing multiple USRP X310s from the same manufacturer,with fewer parameters and less computation than a network model with the same identification *** algorithm is used to identify measurement and control signals and ensure the security of the measurement and control link with theoretical and engineering applications.

关键词： measurement and control security radio frequency(RF)fingerprinting identity identification deep learning

Multi-objective robust secure beamforming for cognitive satellite and UAV networks

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Journal of Systems Engineering and Electronics 2021年第4期32卷 789-798页

作者： WANG Zining LIN Min tang xiaogang GUO Kefeng HUANG Shuo CHENG Ming School of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China School of Space Information Space Engineering UniversityBeijing 101407China Shanghai Aerospace Electronic Technology Institute Shanghai 201109China

A multi-objective optimization based robust beamforming(BF)scheme is proposed to realize secure transmission in a cognitive satellite and unmanned aerial vehicle(UAV)*** the satellite network coexists with the UAV network,we first consider both achievable secrecy rate maximization and total transmit power minimization,and formulate a multi-objective optimization problem(MOOP)using the weighted Tchebycheff ***,by supposing that only imperfect channel state information based on the angular information is available,we propose a method combining angular discretization with Taylor approximation to transform the non-convex objective function and constraints to the convex ***,we adopt semi-definite programming together with randomization technology to solve the original MOOP and obtain the BF weight ***,simulation results illustrate that the Pareto optimal trade-off can be achieved,and the superiority of our proposed scheme is confirmed by comparing with the existing BF schemes.

关键词： cognitive satellite and unmanned aerial vehicle network(CSUN) multi-objective optimization robust secure beamforming(BF) weighted Tchebycheff approach

QoS-Aware Power Allocation Scheme for Relay Satellite Networks

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Journal of Beijing Institute of Technology 2021年第1期30卷 82-90页

作者： Jin’ao Yu xiaogang tang Shibing Zhu Haopeng Sun Lunxin Zhong Guangyu Yang School Space Engineering UniversityBeijing 101416China School of Space Information Space Engineering UniversityBeijing 101416China

This paper investigated a QoS-aware power allocation for relay satellite *** the given QoS requirements,we analyzed the signal model of relay transmission and formulated the power minimization problem which is non-convex and difficult to *** find the optimal solution to the considered problem,we first analyzed the optimization problem and equivalently turn it into a convex optimization ***,we provided a Lagrangian dual-based method to obtain the closed-form of the power allocation and provided an iterative algorithm to the optimal ***,we also extended the results to the cooperative transmission ***,simulation results were provided to verify the superiority of the proposed algorithm.

关键词： power allocation relay satellite network quality of service cooperative transmission

The Impact of Government Supervision and Consumer Purchasing Behavior on Food Safety

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Journal of Agricultural Chemistry and Environment 2014年第4期3卷 7-12页

作者： Yuan Chen xiaogang tang Kangyu Chen Hui Liu School of Economics & Commerce Guangdong University of Technology Guangzhou China

This paper aims at the theoretical analysis to the impact of government supervision and consumer purchasing behavior on food quality security, so as to look for safety strategies and measures to strengthen and improve the level of food safety in China. Reputation mechanism is introduced and Bayesian approach is based on, in which government supervision as well as consumer purchasing behavior is taken as crucial factors to impact on the food quality security. As to the proposed quantitative indicators, government supervision includes exposure rate, fine and etc.;at the same time, consumer purchasing behavior includes consumer’s WTP for security food and consumer expectations to food safety. Taking China’s dairy industry as an example, it makes simulation by Netlog. The results show that consumer purchasing behavior alone has little effect on the dairy companies’ decision-making to be honest or counterfeiting enterprises. However, combination government supervision with purchasing behavior has great impact, and plays very good effects on food safety.

关键词： Food Safety Reputation Mechanism Government Supervision Customer’s Willingness to Pay

Microstructure and Wear/corrosion Resistance of Stainless Steel Laser-alloyed with Mn+W_(2)C, Mn+NiWC and Mn+SiC

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 283-294页

作者： ZHOU Rui DIAO xiaogang SUN Yixin School of Metallurgical Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600China CITIC Heavy Cast Iron Industry Co. Ltd.Luoyang 417039China

In-situ formed high Mn steel coating reinforced by carbides was formed by laser surface alloying(LSA).Laser alloyed layers on 1Cr18Ni9Ti steel with Mn+W_(2)C(specimen A),Mn+NiWC(specimen B)and Mn+SiC(specimen C)powders were fabricated to improve the wear and corrosion behavior of 1Cr18Ni9Ti steel blades in high speed *** evolution,phases,element distribution,microhardness,wear and corrosion behavior of the laser alloyed layers were *** indicated that high Mn steel matrix composites with undissolved W_(2)C,WC and other in-situ formed carbides were formed by LSA with Mn+W_(2)C and Mn+NiWC while SiC totally dissolved into the high Mn matrix when adding Mn+*** as the binding phase in Ni-WC powder decreased the crack sensitivity of the alloyed layer as compared with the addition of W_(2)C *** improvement in average microhardness was achieved in the matrix in specimen A,B and C,with the value of 615,602 and 277 HV_(0.5),while that of the substrate was 212 HV_(0.5).The increase of microhardness,wear and corrosion resistance is highly corelated to microstructure,formed phases,type and content of carbides,micro-hardness and toughness of the alloyed layers.

关键词： laser surface alloying stainless steel carbide type microstructure wear and corrosion resistance

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政治正义观的历史演进与当代价值

盐城工学院学报（社会科学版） 2015年第3期28卷 24-27页

作者：唐孝岗江苏省委党校江苏南京210004

政治正义观是政治哲学研究中的重要议题。古典政治正义观发展到今天,对于我国社会主义现代化建设仍具有时代价值。通过对政治正义观发展历史的梳理,以马克思主义的分析方法对当代政治正义的核心话题展开追问,探寻其对中国社会主义现代... 详细信息

政治正义观是政治哲学研究中的重要议题。古典政治正义观发展到今天,对于我国社会主义现代化建设仍具有时代价值。通过对政治正义观发展历史的梳理,以马克思主义的分析方法对当代政治正义的核心话题展开追问,探寻其对中国社会主义现代化建设的当代价值。

关键词：政治正义观马克思主义分析哲学

用阿奇霉素治疗小儿肺炎支原体感染的有效性和安全性

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当代医药论丛 2018年第9期16卷 19-20页

作者：唐小刚彭州市妇幼保健院四川成都611930

目的:分析用阿奇霉素治疗小儿肺炎支原体感染的有效性和安全性。方法:将2015年7月至2017年9月期间彭州市妇幼保健院收治的100例小儿肺炎支原体感染患儿按用药方法的不同分为观察组和对照组(50例/组)。在两组患儿住院期间,用红霉素对对... 详细信息

目的:分析用阿奇霉素治疗小儿肺炎支原体感染的有效性和安全性。方法:将2015年7月至2017年9月期间彭州市妇幼保健院收治的100例小儿肺炎支原体感染患儿按用药方法的不同分为观察组和对照组(50例/组)。在两组患儿住院期间,用红霉素对对照组患儿进行治疗,用阿奇霉素对观察组患儿进行治疗。治疗5 d后,对比两组患儿治疗的效果、临床症状消退的情况、进行肺炎支原体和肺炎衣原体检查的结果、用药不良反应的发生情况。结果:与对照组患儿相比,观察组患儿治疗的总有效率较高,治疗后其退热的时间、咳嗽症状消失的时间、肺部啰音消失的时间、肺部阴影消失的时间均较短,对其进行肺部支原体和肺部衣原体检查的阳性率均较低,其用药不良反应的总发生率较低,P<0.05。结论:用阿奇霉素治疗小儿肺炎支原体感染的有效性和安全性均较好,且可缩短患儿临床症状消退的时间,加快其康复的速度。

关键词：小儿肺炎支原体感染阿奇霉素红霉素