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Joint waveform selection and power allocation algorithm in manned/unmanned aerial vehicle hybrid swarm based on chance-constraint programming

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Journal of Systems Engineering and Electronics 2022年第3期33卷 551-562页

作者： ZhanG Yuanshi PAN Minghai LONG Weijun LI Hua han qinghua College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China Nanjing Research Institute of Electronics Technology Nanjing 210039China College of Artificial Intelligence Zaozhuang UniversityZaozhuang 277160China

In this paper, we propose a joint waveform selection and power allocation(JWSPA) strategy based on chance-constraint programming(CCP) for manned/unmanned aerial vehicle hybrid swarm(M/UAVHS) tracking a single target. Accordingly,the low probability of intercept(LPI) performance of system can be improved by collaboratively optimizing transmit power and waveform. For target radar cross section(RCS) prediction, we design a random RCS prediction model based on electromagnetic simulation(ES) of target. For waveform selection, we build a waveform library to adaptively manage the frequency modulation slope and pulse width of radar waveform. For power allocation,the CCP is employed to balance tracking accuracy and power resource. The Bayesian Cramér-Rao lower bound(BCRLB) is adopted as a criterion to measure target tracking accuracy. The hybrid intelli gent algorithms, in which the stochastic simulation is integrated into the genetic algorithm(GA), are used to solve the stochastic optimization problem. Simulation results demonstrate that the proposed JWSPA strategy can save more transmit power than the traditional fixed waveform scheme under the same target tracking accuracy.

关键词： multistatic radar system(MRS) target tracking manned/unmanned aerial vehicle hybrid swarm(M/UAVHS) power allocation waveform selection

Development of a double-layer shaking table for large-displacement high-frequency excitation

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Earthquake Engineering and Engineering Vibration 2022年第1期21卷 193-207页

作者： Pan Peng Guo Youming Kang Yingjie Wang Tao han qinghua Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationSanhe 065201China Department of Civil Engineering Tsinghua UniversityBeijing 100084China School of Civil Engineering Tianjin UniversityTianjin 300350China

It is difficult to conduct shaking table tests that require large-displacement high-frequency seismic excitation due to the limited capacity of existing electrohydraulic servo *** address this problem,a double-layer shaking table(DLST)is *** DLST has two layers of one table each(i.e.,an upper table and lower table)and aims at reproducing target seismic excitation on the upper *** original signal is separated into two signals(i.e.,a high-frequency signal and low-frequency signal)through a fast Fourier transform/inverse fast Fourier transform process,and these signals are applied to the two tables *** actuators connected to different tables only need to generate large-displacement low-frequency or small-displacement high-frequency *** three-variable control method is used to generate large-displacement but low-frequency motion of the lower table and high-frequency but small-displacement motion of the upper table relative to the table beneath.A series of simulations are carried out using MATLAB/*** simulation results suggest that the DLST can successfully generate large-displacement high-frequency *** control strategy in which the lower table tracks the low-frequency signal and the upper table tracks the original signal is recommended.

关键词： double-layer shaking table large-displacement high-frequency excitation electrohydraulic servo system three-variable control MATLAB/Simulink

Runtime support for type-safe and context-based behavior adaptation

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Frontiers of Computer Science 2014年第1期8卷 17-32页

作者： Changpeng ZHU Yinliang ZHAO Bo han qinghua ZENG Ying MA Department of Computer Science Xi'an Jiaotong University Xi'an 710049 China

Context-awareness is becoming critical for mo- bile and ubiquitous computing, where the application needs dynamically adapt its behavior to its execution environment. Context-oriented programming （COP） languages support dy- namic behavior adaptation, however, they do not support dy- namic layer addition. As a result, they provide little support for the runtime adaptation of application behavior in case that unpredictable execution environments are encountered. Furthermore, block-structured constructs for layer activation hardly support fine-grain adaptation and separate changes of contexts and execution of context-specific methods with dif- ficulty. In this paper, we propose a virtual machine （VM）- centric approach to address these issues. It incorporates ob- ject composition and delegation into the VM to implement layer activation, and extends existing VM services to sup- port dynamic layer addition. To ensure that our approach preserves the type safety properties of the program, we de- velop a calculus built on featherweight Java （FJ） to describe the approach, focus on type-checking issues, and prove type soundness of the calculus. We also present the implementa- tion and evaluation of our approach. The evaluation demon- strates that our approach has advantages over the compiler- based approach proposed by JCOP.

关键词： context-orientedprogramming object composi-tion delegation featherweight Java type system

Impacts of space-time-frequency synchronization errors onwide-band target echo characteristics of bistatic/multistatic radar

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Journal of Systems Engineering and Electronics 2016年第3期27卷 562-573页

作者： Minghai Pan qinghua han Shufeng Gong Weijun Long Haitao Wei Key Laboratory of Radar Imaging and Microwave Photonics College of Electronic and Information EngineeringNanjing University of Aeronautics and AstronauticsNanjing 211106China Nanjing Research Institute of Electronics Technology Nanjing 210039China State Key Laboratory of Satellite Navigation System and Equipment Technology Shijiazhuang 050081China

Bistatic/multistatic radar has great potential advantages over its monostatic counterpart. However, the separation of a transmitter and a receiver leads to difficulties in locating the target position accurately and guaranteeing space-timefrequency synchronization of the transmitter and the *** error model of space-time-frequency synchronization in a motion platform of bistatic/multistatic radar is studied. The relationship between the space synchronization error and the transmitter platform position, receiver platform position, moving state, and beam pointing error, is analyzed. The effect of space synchronization error on target echo power is studied. The target scattering characteristics are restructured by many separate scattering centers of the target in high frequency regions. Based on the scattering centers model of the radar target, this radar target echo model and the simulation method are discussed. The algorithm of bistatic/multistatic radar target echo accurately reflects the scattering characteristics of the radar target, pulse modulation speciality of radar transmitting signals, and spacetime-frequency synchronization error characteristics between the transmitter station and the receiver station. The simulation of bistatic radar is completed in computer, and the results of the simulation validate the feasibility of the method.

关键词： bistatic/multistatic radar space-time-frequency synchronization motion platform synchronization error radar target echo model

Gas decomposition and electrode degradation characteristics of a 20%C_(3)F_(7)CN and 80%CO_(2) gas mixture for high voltage accelerators

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High Voltage 2021年第5期6卷 750-759页

作者： Ibrahim Iddrissu qinghua han Lujia Chen Louis Maksoud Yannick Kieffel Department of Electrical and Electronic Engineering The University of ManchesterManchesterUK Materials Research Department General ElectricGrid Solutions SASVilleurbanneFrance

Sulphur hexafluoride(SF_(6))is a potent greenhouse gas used in high voltage *** a promising alternative to SF_(6),the C_(3)F_(7)CN/CO_(2)gas mixture and its by‐products are of great interest to ensure the safe operation of accelerators that will adopt any SF_(6)‐free *** work experimentally examines the electrical ageing characteristics of a 20%C_(3)F_(7)CN/80%CO_(2)gas mixture tested using spark gaps under a pressure of 7.2 bar(abs.).Gas samples were collected after 1000 DC breakdowns and analysed using gas chro-matography mass spectrometry(GC‐MS)with an estimated toxicity value of 54,459 ppmv,which indicates the aged mixture to be non‐*** investigation was conducted on the gas‐solid interface after 500 breakdowns for both SF_(6) and the 20%C_(3)F_(7)CN/80%CO_(2)gas *** electrodes were analysed using X‐ray photoelec-tron spectroscopy(XPS)and X‐ray diffraction(XRD)*** surface analysis revealed the formation of metal fluorides on the electrode surface tested using the 20%C_(3)F_(7)CN/80%CO_(2)mixture,whereas metal fluorides and sulphides were detected for electrodes tested with SF_(6).The findings provide a reference on the toxicity and gas‐solid interaction of the electrically aged 20%C_(3)F_(7)CN/80%CO_(2)gas mixture for potential retro‐fill application in high voltage accelerators.

关键词： mixture electrode characteristics

A BOOSTING APPROACH FOR INTRUSION DETECTION

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Journal of Electronics(China) 2007年第3期24卷 369-373页

作者： Zan Xin han Jiuqiang Zhang Junjie Zheng qinghua han Chongzhao Dept of Automation School of Electronics and Information Engineering Xi＇an Jiaotong University Xi＇an 710040 China

Intrusion detection can be essentially regarded as a classification problem,namely,dis-tinguishing normal profiles from intrusive behaviors. This paper introduces boosting classification algorithm into the area of intrusion detection to learn attack signatures. Decision tree algorithm is used as simple base learner of boosting algorithm. Furthermore,this paper employs the Principle Com-ponent Analysis (PCA) approach,an effective data reduction approach,to extract the key attribute set from the original high-dimensional network traffic data. KDD CUP 99 data set is used in these ex-periments to demonstrate that boosting algorithm can greatly improve the classification accuracy of weak learners by combining a number of simple “weak learners”. In our experiments,the error rate of training phase of boosting algorithm is reduced from 30.2% to 8% after 10 iterations. Besides,this paper also compares boosting algorithm with Support Vector Machine (SVM) algorithm and shows that the classification accuracy of boosting algorithm is little better than SVM algorithm’s. However,the generalization ability of SVM algorithm is better than boosting algorithm.

关键词： Network security Intrusion Detection System (IDS) Machine learning Boosting algo-rithm Decision tree Support Vector Machine (SVM)

Enhanced interfacial polarization of defective porous carbon confined CoP nanoparticles forming Mott-Schottky heterojunction for efficient electromagnetic wave absorption

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Nano Research 2023年第3期16卷 4160-4169页

作者： Baojun Wang Fangzhi Huang Hao Wu Zijie Xu Shipeng Wang qinghua han Fenghua Liu Shikuo Li Hui Zhang School of Materials Science and Engineering Anhui UniversityHefei 230601China School of Chemistry and Chemical Engineering Anhui UniversityHefei 230601China Ningbo Institute of Materials Technology and Engineering Chinese Academy of ScienceNingbo 315201China Key Laboratory of Structure and Functional Regulation of Hybrid Materials(Anhui University) Ministry of EducationHefei 230601China

Integrating heterogeneous interface through nanostructure design and interfacial modification is essential to realize strengthened interfacial polarization relaxation in electromagnetic wave ***,an in-depth comprehension of the interfacial polarization behavior at hetero-junction/interface is highly desired but remains a great ***,a Mott-Schottky heterojunction consisting of honeycomb-like porous N-doped carbon confined CoP nanoparticles(CoP@HNC)is designed to elevate the interfacial polarization ***,corresponding electron migration and redistribution between the heterointerface of defective carbon and CoP nanoparticles are *** significant difference in the work function on both sides of heterogeneous interface boosts the interfacial polarization in high frequency ***,the relevant spectroscopic characterizations demonstrate that electron spontaneously migrates from CoP to N-doped carbon at the heterointerface,thereby contributing to the accumulation of electron on defective carbon side and the distribution of hole on CoP ***,benefitting from the synergistic effects of three-dimensional porous conductive carbon skeleton,foreign N heteroatoms,special CoP nanoparticles,and the resultant CoP/N-doped carbon Mott-Schottky heterojunction,the CoP@HNC exhibits remarkable electromagnetic wave absorption performances with minimum reflection loss up to−60.8 dB and the maximum effective absorption bandwidth of 4.96 GHz,which is superior to most of recently reported transition metal phosphides microwave absorbing *** present work opens a new avenue for designing heterogeneous interface to realize strengthened microwave absorption capability and also reveals the in-depth influence of interface structure on electromagnetic wave absorption.

关键词： honeycomb-like structure Mott-Schottky heterojunction interfacial polarization electron transfer microwave absorption

Degradation of superhydrophobic aluminium overhead line conductor surfaces

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High Voltage 2024年第4期9卷 763-772页

作者： Xu Zhang Chorphaka Plaengpraphan Chengxing Lian Wenyuan Li qinghua han Simon M.Rowland Ian Cotton Qi Li School of Engineering University of WarwickCoventryUK State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina School of Engineering University of ManchesterManchesterUK School of Engineering Imperial College LondonLondonUK Electrical Engineering School Chongqing UniversityChongqingChina

It has been shown that noise emissions from HV overhead line conductors can be reduced under rain conditions by making their surfaces *** working environment makes ensuring the longevity of any treatment a major *** degradation of various superhydrophobic surfaces generated by applying a superhydrophobic coating and patterning microscale channels is assessed under an AC electric field(18 kV/cm)with continuous water *** examining the droplet distribution on the surfaces during the degradation and the surface roughness before and after degra-dation,the authors demonstrate that no water droplets were found on the microscale patterned surface,but droplets were formed on the coated surface after *** surface roughness reduction of the coated surface and microscale patterned surface was 29.8% and 11.3%,respectively,indicating that the microscale patterned surface has better durability than the superhydrophobic coating under the AC electric stress.

关键词： coating roughness surface

Pharmacologically targeting molecular motor promotes mitochondrial fission for anti-cancer

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Acta Pharmaceutica Sinica B 2021年第7期11卷 1853-1866页

作者： Yi Qian Meimei Zhao qinghua han Jingkang Wang Lixi Liao Heng Yang Dan Liu Pengfei Tu Hong Liang Kewu Zeng State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Proteomics Laboratory Medical and Healthy Analytical CenterPeking University Health Science CenterBeijing 100191China

Mitochondrial shape rapidly changes by dynamic balance of fusion and fission to adjust to constantly changing energy demands of cancer *** dynamics balance is exactly regulated by molecular motor consisted of myosin and actin cytoskeleton ***,targeting myosin eactin molecular motor is considered as a promising strategy for *** this study,we performed a proof-of-concept study with a natural-derived small-molecule J13 to test the feasibility of anti-cancer therapeutics via pharmacologically targeting molecular ***,we found J13 could directly target myosin-9(MYH9)eactin molecular motor to promote mitochondrial fission progression,and markedly inhibited cancer cells survival,proliferation and *** study revealed that J13 impaired MYH9 eactin interaction to inactivate molecular motor,and caused a cytoskeleton-dependent mitochondrial dynamics ***,stable isotope labeling with amino acids in cell culture(SILAC)technology-coupled with pulldown analysis identified HSPA9 as a crucial adaptor protein connecting MYH9 eactin molecular motor to mitochondrial *** together,we reported the first natural small-molecule directly targeting MYH9 eactin molecular motor for anti-cancer translational ***,our study also proved the conceptual practicability of pharmacologically disrupting mitochondrial fission/fusion dynamics in human cancer therapy.

关键词： Anti-cancer Liver hepatocellular carcinoma Mitochondrial fission Small molecule Target identification Molecular motor MYH9 HSPA9