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A high performance waveform and a new ranging method for the proximity detector

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Defence Technology（防务技术） 2020年第4期16卷 834-845页

作者： Qi-le Chen xin-hong hao Xiao-peng Yan Ping Li School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

Signal modulation is an essential design factor for proximity detectors and directly affects the system's potential *** order to achieve the advantages of chaotic codes bi-phase modulation(CCBPM)and linear frequency modulation(LFM) simultaneously,this paper designed a waveform which combined chaotic codes bi-phase modulation and linear frequency modulation(CCBPM-LFM) for proximity *** CCBPM-LFM waveform was analyzed in the aspect of time delay resolution(TDR) and Doppler tolerance(DT) based on ambiguity function(AF).Then,a ranging method,which we called instant correlation harmonic demodulation(ICHD),was presented for the detector using the CCBPM-LFM *** combining time domain instant correlation with harmonic demodulation,the ICHD solved the problem caused by combination modulation and made the most of the linear frequency modulation(LFM) harmonics and the correlation of chaotic ***,a prototype was implemented and ranging experiments were carried *** the theoretical analysis and experimental results,the proximity detector used the CCBPM-LFM waveform has an outstanding detection performance.

关键词： Proximity detectors Detection performance Combination modulation Chaotic codes bi-phase modulation Linear frequency modulation

Adaptive target and jamming recognition for the pulse doppler radar fuze based on a time-frequency joint feature and an online-updated naive bayesian classifier with minimal risk

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Defence Technology（防务技术） 2022年第3期18卷 457-466页

作者： Jian Dai xin-hong hao Ze Li Ping Li Xiao-peng Yan Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing100081China

This paper considers the problem of target and jamming recognition for the pulse Doppler radar fuze(PDRF).To solve the problem,the matched filter outputs of the PDRF under the action of target and jamming are ***,the frequency entropy and peak-to-peak ratio are extracted from the matched filter output of the PDRF,and the time-frequency joint feature is *** on the time-frequency joint feature,the naive Bayesian classifier(NBC)with minimal risk is established for target and jamming *** improve the adaptability of the proposed method in complex environments,an online update process that adaptively modifies the classifier in the duration of the work of the PDRF is *** experiments show that the PDRF can maintain high recognition accuracy when the signal-to-noise ratio(SNR)decreases and the jamming-to-signal ratio(JSR)***,the applicable analysis shows that he ONBCMR method has low computational complexity and can fully meet the real-time requirements of PDRF.

关键词： Pulse Doppler radar fuze(PDRF) Target and jamming recognition Time-frequency joint feature Online-update naive Bayesian classifier minimal risk(ONBCMR)

Repeater jamming suppression method for pulse Doppler fuze based on identity recognition and chaotic encryption

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Defence Technology（防务技术） 2021年第3期17卷 1002-1012页

作者： Jian Dai xin-hong hao Qiang Liu Xiao-peng Yan Ping Li Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China Ordnance Science Institute of China Beijing 100089China

Pulse Doppler(PD) fuze is widely used in current battlefield. However, with the threat of repeater jamming, especially digital radio frequency memory technology, the deficiency in the anti-repeater jamming of a traditional PD fuze increasingly emerges. Therefore, a repeater jamming suppression method for a PD fuze based on identity(ID) recognition and chaotic encryption is proposed. Every fuze has its own ID which is encrypted with different chaotic binary sequences in every pulse period of the transmitted signal. The thumbtack-shaped ambiguity function shows a good resolution and distance cutoff characteristic. The ability of anti-repeater jamming is emphatically analyzed, and the results at different signal-to-noise ratio(SNR) show a strong anti-repeater jamming ability and range resolution that the proposed method possesses. Furthermore, the anti-repeater jamming ability is influenced by processing gain, bit error rate(BER) and correlation function. The simulation result validates the theoretical analysis, it shows the proposed method can significantly improve the anti-repeater jamming ability of a PD fuze.

关键词： Pulse Doppler fuze ID Chaotic binary code Encryption Repeater jamming

A novel DOA estimation algorithm using directional antennas in cylindrical conformal arrays

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Defence Technology（防务技术） 2021年第3期17卷 1042-1051页

作者： Xiao-feng Gao Ping Li xin-hong hao Guo-lin Li Zhi-jie Kong Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing100081China China Academy of Launch Vehicle Technology Beijing100076China

In this paper, a novel direction of arrival(DOA) estimation algorithm using directional antennas in cylindrical conformal arrays(CCAs) is proposed. To eliminate the shadow effect, we divide the CCAs into several subarrays to obtain the complete output vector. Considering the anisotropic radiation pattern of a CCA, which cannot be separated from the manifold matrix, an improved interpolation method is investigated to transform the directional subarray into omnidirectional virtual nested arrays without non-orthogonal perturbation on the noise vector. Then, the cross-correlation matrix(CCM) of the subarrays is used to generate the consecutive co-arrays without redundant elements and eliminate the noise vector. Finally, the full-rank equivalent covariance matrix is constructed using the output of co-arrays,and the unitary estimation of the signal parameters via rotational invariance techniques(ESPRIT) is performed on the equivalent covariance matrix to estimate the DOAs with low computational complexity. Numerical simulations verify the superior performance of the proposed algorithm, especially under a low signal-to-noise ratio(SNR) environment.

关键词： Direction of arrival(DOA) Conformal antenna array Interpolation technique Nested array

Weak wide-band signal detection method based on small-scale periodic state of Duffing oscillator

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Chinese Physics B 2018年第3期27卷 205-215页

作者： Jian Hou Xiao-peng Yan Ping Li xin-hong hao Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical Engineering Beijing Institute of Technology Beijing 100081 China

The conventional Duffing oscillator weak signal detection method, which is based on a strong reference signal, has inherent deficiencies. To address these issues, the characteristics of the Duffing oscillator＇s phase trajectory in a small- scale periodic state are analyzed by introducing the theory of stopping oscillation system. Based on this approach, a novel Duffing oscillator weak wide-band signal detection method is proposed. In this novel method, the reference signal is discarded, and the to-be-detected signal is directly used as a driving force. By calculating the cosine function of a phase space angle, a single Duffing oscillator can be used for weak wide-band signal detection instead of an array of uncoupled Duffing oscillators. Simulation results indicate that, compared with the conventional Duffing oscillator detection method, this approach performs better in frequency detection intervals, and reduces the signal-to-noise ratio detection threshold, while improving the real-time performance of the system.

关键词： Duffing oscillator weak signal detection stopping oscillation system small-scale periodic state

AZD1775 synergizes with SLC7A11 inhibition to promote ferroptosis

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Science China Life Sciences 2025年第1期68卷 204-218页

作者： Chen Xiong hong Ling Yingdan Huang Hanzhi Dong Bangxiang Xie Qian hao Xiang Zhou Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences Fudan University Department of Oncology Shanghai Medical CollegeFudan University Department of Breast Surgery Fudan University Shanghai Cancer CenterFudan University Department of Oncology First Affiliated Hospital of Nanchang University Beijing Institute of Hepatology Beijing Youan HospitalCapital Medical University Beijing Engineering Research Center for Precision Medicine and Transformation of Hepatitis and Liver Cancer Key Laboratory of Breast Cancer in Shanghai Fudan University Shanghai Cancer CenterFudan University Shanghai Key Laboratory of Medical Epigenetics International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology)Institutes of Biomedical SciencesFudan University

Tumor suppressor p53-mediated cell cycle arrest and DNA damage repair may exert cytoprotective effects against cancer therapies, including WEE1 inhibition. Considering that p53 activation can also lead to multiple types of cell death, the role of this tumor suppressor in WEE1 inhibitor-based therapies remains disputed. In this study, we reported that nucleolar stress-mediated p53 activation enhanced the WEE1 inhibitor AZD1775-induced ferroptosis to suppress lung cancer growth. Our findings showed that AZD1775 promoted ferroptosis by blocking cystine uptake, an action similar to that of Erastin. Meanwhile, inhibition of WEE1 by the WEE1 inhibitors or si RNAs induced compensatory upregulation of SLC7A11, which conferred resistance to ferroptosis. Mechanistically, AZD1775 prevented the enrichment of H3K9me3, a histone marker of transcriptional repression, on the SLC7A11 promoter by repressing the expression of the histone methyltransferase SETDB1, thereby enhancing NRF2-mediated SLC7A11 transcription. This finding was also validated using the H3K9me3 inhibitor BRD4770. Remarkably, we found that the nucleolar stress-inducing agent Actinomycin D(Act. D) inhibited SLC7A11 expression by activating p53, thus augmenting AZD1775-induced ferroptosis. Moreover, the combination of AZD1775 and Act. D synergistically suppressed wild-type p53-harboring lung cancer cell growth both in vitro and in vivo. Altogether, our study demonstrates that AZD1775 promotes ferroptosis by targeting cystine uptake but also mediates the adaptive activation of SLC7A11 through the WEE1-SETDB1 cascade and NRF2-induced transcription, and inhibition of SLC7A11 by Act. D boosts the anti-tumor efficacy of AZD1775 by enhancing ferroptosis in cancers with wild-type p53.

关键词： p53 NRF2 SLC7A11 WEE1 AZD1775 ferroptosis nucleolar stress

A Mn-porphyrinic metal–organic framework immobilizing glucose oxidase for combined photodynamic/chemodynamic/starvation therapy

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Tungsten 2025年第1期7卷 183-194页

作者： xin-Ran Sun hao-Ming Yuan Guo-Da Zhang Chao Wang Shu-Juan Sun Peng-Fei Shi Shandong Provincial Key Laboratory of Detection Technology for Tumor Markers School of Chemistry and Chemical Engineering Linyi University

The combination of photodynamic therapy（PDT） and chemodynamic therapy（CDT） in tumor treatment has attracted considerable ***,tumor hypoxia and glutathione（GSH） overproduction in the tumor tissue restricted the progress of their ***,a Mn-porphyrinic metal-organic framework（Mn-TCPP） was constructed by the one-pot method and further used for immobilizing glucose oxidase（GOx） to obtain GOx@*** would rapidly exhaust endogenous glucose into hydrogen peroxide（H2O2） and gluconic acid,thus shutting off the energy supply of tumor cells for starvation ***-TCPP catalyzed H2O2to produce oxygen,regulating the hypoxic tumor microenvironment and in turn improving1O2generation under laser ***,Mn-TCPP can reduce reactive oxygen species consumption owing to the redox reaction between Mn3+and GSH,thus greatly enhancing ***,benefiting from GOx-mediated starvation therapy,Mn2+produced by Mn3+reduction can react with sufficient intracellular H2O2to generate ·OH with high cytotoxicity through a Fenton-like *** treatment by GOx@Mn-TCPP under laser irradiation in vitro,the cell viability of 4T1 and A549 tumor cells reached to 20%,reflecting GOx@Mn-TCPP could give full play to the advantages of PDT/CDT/starvation *** results in vivo demonstrated that GOx@Mn-TCPP mediated synergistic cascade therapy could significantly inhibit tumor growth and improve the therapeutic effect.

关键词： Chemodynamic therapy Immobilizing enzyme Metal–organic frameworks Photodynamic therapy Starvation therapy

Advances in Graphene‑Based Electrode for Triboelectric Nanogenerator

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Nano-Micro Letters 2025年第1期17卷 378-403页

作者： Bin Xie Yuanhui Guo Yun Chen hao Zhang Jiawei Xiao Maoxiang Hou Huilong Liu Li Ma xin Chen Chingping Wong State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006People’s Republic of China School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006People’s Republic of China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

With the continuous development of wearable electronics,wireless sensor networks and other micro-electronic devices,there is an increasingly urgent need for miniature,flexible and efficient nanopower generation *** nanogenerator(TENG)technology can convert small mechanical energy into electricity,which is expected to address this *** the core component of TENG,the choice of electrode materials significantly affects its *** metal electrode materials often suffer from problems such as durability,which limits the further application of ***,as a novel electrode material,shows excellent prospects for application in TENG owing to its unique structure and excellent electrical *** review systematically summarizes the recent research progress and application prospects of TENGs based on graphene *** precision processing methods of graphene electrodes are introduced,and the applications of graphene electrode-based TENGs in various scenarios as well as the enhancement of graphene electrodes for TENG performance are *** addition,the future development of graphene electrode-based TENGs is also prospectively discussed,aiming to promote the continuous advancement of graphene electrode-based TENGs.

关键词： Triboelectric nanogenerator Precision processing Graphene electrode Self-powered sensor

Constructing 2D bismuth-based heterostructure for highly efficient photocatalytic CO2 reduction

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Tungsten 2025年第1期7卷 71-79页

作者： Ruo-Hang Xu hao-Yu Jiang Dan-Dan Cui Kun-Rong Du hong-Run Zhang Sheng-Jie Xu Ya-Qi Li Zhi-Zhen Ren Liang Wang Wei-Chang hao Yi Du School of Physics and BUAA-UOW Joint Research Centre Beihang University Shenzhen Institute of Beihang University Centre for Catalysis and Clean Energy School of Environment and Science Griffith University

Reforming carbon dioxide（CO2） into fuels and valuable chemicals using solar energy holds significant potential for emission reduction and addressing energy supply *** recombination of photocarriers remains a major obstacle,however,to enhancing solar energy conversion efficiency in the photocatalytic reaction *** two-dimensional materials,constructing heterogeneous structures has emerged as an effective strategy to enhance the separation of photoexcited carriers by leveraging the internal electric field at the heterogeneous ***,we present a facile strategy for preparing Bi4NbO8Br/Bi2WO6plate-on-plate Z-scheme junctions with a strong internal electric field by in situ *** unique heterostructure facilitates efficient separation and transport of photoexcited charges by harnessing the internal electric field induced by chemical bonding at the lateral ***,the Bi4NbO8Br/Bi2WO6heterostructure exhibits enhanced CO2photoreduction properties,along with a CO yield rate of approximately 35 μmol·g-1·h-1under full light *** work offers novel insights into the synthesis of unique hetero structures intended to enhance the efficiency of photocatalytic CO2reduction.

关键词： Bi4NbO8Br/Bi2WO6 CO2 reduction Heterostructures Photocatalysts