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Guaranteed Cost Attitude Tracking Control for Uncertain Quadrotor Unmanned Aerial Vehicle Under Safety Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1447-1457页

作者： Qian ma Peng Jin Frank L.Lewis School of Automation Nanjing University of Science and TechnologyNanjing 210094China UTA Research Institute University of Texas at ArlingtonFort WorthTexas 76118 USA IEEE

In this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is ***,an augmented system is constructed by the tracking error system and reference *** transformation aims to convert the tracking control prob-lem into a stabilization control ***,control barrier function and disturbance attenuation function are designed to characterize the violations of safety constraints and tolerance of uncertain disturbances,and they are incorporated into the reward function as penalty *** on the modified reward function,the problem is simplified as the optimal regulation problem of the nominal augmented system,and a new Hamilton-Jacobi-Bellman equation is ***,critic-only rein-forcement learning algorithm with a concurrent learning tech-nique is employed to solve the Hamilton-Jacobi-Bellman equa-tion and obtain the optimal *** proposed algorithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety *** performance of the algorithm is evaluated by the numerical simulation.

关键词： Attitude tracking control quadrotor unmanned aerial vehicle(QUAV) reinforcement learning safety constraints uncertain disturbances.

Metallurgical performance evaluation of space-weathered Chang’e-5 lunar soil

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International Journal of Minerals,Metallurgy and materials 2024年第6期31卷 1241-1248页

作者： Chen Li Wenhui ma Yang Li Kuixian Wei Center for Lunar and Planetary Sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China

Space metallurgy is an interdisciplinary field that combines planetary space science and metallurgical *** involves systematic and theoretical engineering technology for utilizing planetary resources in ***,space metallurgy on the Moon is challenging because the lunar surface has experienced space weathering due to the lack of atmosphere and magnetic field,making the mi-crostructure of lunar soil differ from that of minerals on the *** this study,scanning electron microscopy and transmission electron microscopy analyses were performed on Chang’e-5 powder lunar soil *** microstructural characteristics of the lunar soil may drastically change its metallurgical *** main special structure of lunar soil minerals include the nanophase iron formed by the impact of micrometeorites,the amorphous layer caused by solar wind injection,and radiation tracks modified by high-energy particle rays inside mineral *** nanophase iron presents a wide distribution,which may have a great impact on the electromagnetic prop-erties of lunar *** ions injected by solar wind may promote the hydrogen reduction *** widely distributed amorph-ous layer and impact glass can promote the melting and diffusion process of lunar ***,although high-energy events on the lun-ar surface transform the lunar soil,they also increase the chemical activity of the lunar *** is a property that earth samples and tradi-tional simulated lunar soil *** application of space metallurgy requires comprehensive consideration of the unique physical and chemical properties of lunar soil.

关键词： space metallurgy Chang’e-5 lunar soil space weathering metallurgical performance

Further Results on Stability Analysis for Sampled-Data Systems via Refined Semi-Looped-Functional

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Journal of Systems Science & Complexity 2024年第1期37卷 318-328页

作者： SHENG Zhaoliang XU Shengyuan ma Qian ZHANG Baoyong School of Automation Nanjing University of Science and TechnologyNanjing 210094China

This paper investigates the stability problem for sampled-data systems by adopting a refined semi-looped-functional,which is with the following two ***,the new functional term is with a new integral vectorη0,which contains sampling information of the systems and associates two commonly used ***,the vectorη0 is combined into various zero equations for processing the functional,especially where a new equation is derived fromη*** on the refined functional,further stability results for sampled-data systems are *** the effectiveness of the results is numerically verified through two examples at the end.

关键词： Integral vector sampled-data systems semi-looped-functional stability analysis.

Enhanced properties of stone coal-based composite phase change materials for thermal energy storage

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International Journal of Minerals,Metallurgy and materials 2024年第1期31卷 206-215页

作者： Baoshan Xie Huan ma Chuanchang Li Jian Chen Key Laboratory of Renewable Energy Electric-Technology of Hunan Province School of Energy and Power EngineeringChangsha University of Science and TechnologyChangsha 410114China State Key Laboratory of Disaster Prevention and Reduction for Power Grid Changsha University of Science and TechnologyChangsha 410114China

Phase change materials (PCMs) can be incorporated with low-cost minerals to synthesize composites for thermal energy storage in building *** coal (SC) after vanadium extraction treatment shows potential for secondary utilization in composite *** prepared SC-based composite PCMs with SC as a matrix,stearic acid (SA) as a PCM,and expanded graphite (EG) as an *** combined roasting and acid leaching treatment of raw SC was conducted to understand the effect of vanadium extraction on promoting loading *** showed that the combined treatment of roasting at 900℃ and leaching increased the SC loading of the composite by 6.2%by improving the specific surface *** loading capacity and thermal conductivity of the composite obviously increased by 127%and 48.19%,respectively,due to the contribution of 3wt% *** data were supported by the high load of 66.69%and thermal conductivity of 0.59 W·m^(-1)·K-1of the designed *** obtained composite exhibited a phase change temperature of 52.17℃,melting latent heat of 121.5 J·g^(-1),and good chemical *** SC-based composite has prospects in building applications exploiting the secondary utilization of minerals.

关键词： thermal energy storage phase change material stone coal vanadium extraction secondary utilization

Effects of mixed aerosol on the path loss of NLOS UV communication system

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Optoelectronics Letters 2024年第9期20卷 549-559页

作者： ma Yuzhao ZHOU Jingyi Tianjin Key Laboratory for Advanced Signal Processing Civil Aviation University of ChinaTianjin 300300China College of Electronic Information and Automation Civil Aviation University of ChinaTianjin 300300China

Performance of non-line-of-sight(NLOS)ultraviolet(UV)communication is closely related with the communication range,system geometry and the atmosphere aerosol *** this paper,we investigate the path loss of the NLOS UV ... 详细信息

关键词： communication properties. NLOS

Key points and visible part fusion attention network for occluded pedestrian detection in traffic environments

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Optoelectronics Letters 2024年第7期20卷 430-436页

作者： LIU Peiyu ma Yixuan School of Software Engineering Beijing Jiaotong UniversityBeijing 100044China

Aiming at the problem of low detection accuracy of occluded pedestrian in traffic environments,this paper proposes a key points and visible part fusion network for occluded pedestrian *** proposed algorithm constructs two attention modules by introducing human key points and the bounding box of visible parts respectively,which suppresses the occluded parts in the channel features and spatial features of pedestrian features *** results on CityPersons and Caltech datasets demonstrate the effectiveness of the proposed *** missing rate(MR)is reduced to 40.78 on the Heavy subset of the CityPersons dataset and surpasses many outstanding methods.

关键词： methods. network visible

Diagnostic performance of dynamic contrast-enhanced magnetic resonance imaging parameters and serum tumor markers in rectal carcinoma prognosis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1796-1807页

作者： Ren-Qi Mu Jun-Wei Lv Cai-Yun ma Xiao-Hui ma Dong Xing Hou-Sheng ma Department of Radiology Yantai Mountain HospitalYantai 264001Shandong ProvinceChina Department of Radiology Yantai Yuhuangding HospitalYantai 264000Shandong ProvinceChina Department of Gynaecology Yantai Yuhuangding HospitalYantai 264000Shandong ProvinceChina The First Clinical Medical College Xinjiang Medical UniversityUrumqi 830011Xinjiang Uygur Autonomous RegionChina

BACKGROUND Rectal carcinoma(RC),one of the most common malignancies globally,presents an increasing incidence and mortality year by year,especially among young people,which seriously affects the prognosis and quality of life of *** present,dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)parameters and serum carbohydrate antigen 19-9(CA19-9)and CA125 Levels have been used in clinical practice to evaluate the T stage and differentiation of ***,the accuracy of these evaluation modalities still needs further *** study explores the application and value of these methods in evaluating the T stage and differentiation degree of *** To analyze the diagnostic performance of DCE-MRI parameters combined with serum tumor markers(TMs)in assessing pathological processes and prognosis of RC *** A retrospective analysis was performed on 104 RC patients treated at Yantai Yuhuangding Hospital from may 2018 to January *** were categorized into stages T1,T2,T3,and T4,depending on their T stage and differentiation *** addition,they were assigned to low(L group)and moderate-high differentiation(M+H group)groups based on their differentiation *** levels of DCE-MRI parameters and serum CA19-9 and CA125 in different groups of patients were *** addition,the value of DCE-MRI parameters[volume transfer constant(Ktrans),rate constant(Kep),and extravascular extracellular volume fraction(Ve)in assessing the differentiation and T staging of RC patients was ***,the usefulness of DCE-MRI parameters combined with serum CA19-9 and CA125 Levels in the evaluation of RC differentiation and T staging was *** Ktrans,Ve,CA19-9 and CA125 were higher in the high-stage group and L group than in the low-stage group and M+H Group,respectively(P<0.05).The areas under the curve(AUCs)of the Ktran and Ve parameters were 0.638 and 0.694 in the diagnosis of high and low stages,respectively,and 0.672 and 0

关键词： Rectal carcinoma Volume transfer constant Rate constant Extravascular extracellular volume fraction Serum carbohydrate antigen 19-9 Serum carbohydrate antigen 125

A design scheme for interference suppression based on CWBIM

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High Technology Letters 2024年第2期30卷 179-187页

作者：王蕴哲 ma Tianming JIANG Xiaoxiao ma Honglei School of Electrical and Electronic Engineering Shanghai University of Engineering ScienceShanghai 201620P.R.China

An interference suppression design scheme based on conjugate weighted butterfly interleaving mapping(CWBIM)is proposed for inter-carrier interference(ICI)and inter-subband interference(IBI)in the received signals of universal filtered multi-carrier(UFMC)*** applies an interleaving mapping operation to subtract the interference coefficients of adjacent terms in ICI and IBI twice,thereby achieving suppression effects similar to the self-cancellation(SC)algorithm while maintaining the original data transmission ***,conjugate and complex weighting operations can effectively suppress the impact of phase rotation errors in high-speed mobile channel environments,thereby further improving the bit error rate(BFR)performance of the system,Moreover,butterfly operation can effectively control the computational complexity of the interleaving mapping *** analysis and simulation results show that,compared with the PSC-UFMC algorithm,the CWBIM-UFMC scheme proposed in this paper can effectively suppress ICI and IBI in the received signal without compromising data transmission efficiency and reducing computational complexity,thereby achieving good BER performance of the system.

关键词： universal filtered multi-carrier(UFMC) inter-carrier interference(ICI) intersubband interference(IBI) butterfly interleaving mapping

Simulation of nuclear isomer production in laser-induced plasma

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matter and Radiation at Extremes 2024年第5期9卷 1-9页

作者： Zhiguo ma Yumiao Wang Yi Yang Youjing Wang Kai Zhao Yixin Li Changbo Fu Wanbing He Yugang ma Key Laboratory of Nuclear Physics and Ion-Beam Application(MoE) Institute of Modern PhysicsFudan UniversityShanghai 200433China

Nuclear isomers play essential roles in various fields,including stellar nucleosynthesis,nuclear clocks,nuclear batteries,clean nuclear energy,and-ray *** technological advances in high-intensity lasers have made it possible to excite or de-excite nuclear isomers using table-top laser *** a particle-in-cell code,we investigate the interaction of a laser with a nanowire array and calculate the production rates of the^(73m)Ge(E_(1)=13.3 keV)and^(107m)Ag(E_(1)=93.1 keV)***^(73m1)Ge,production by Coulomb excitation is found to contribute a peak efficiency of 1.0×10^(19) particles s^(−1)J^(−1),while nuclear excitation by electron capture(NEEC)contributes a peak of 1.65×10^(11)particles s^(−1)J^(−1).These results indicate a high isomeric production ratio,as well as demonstrating the potential for confirming the existence of NEEC,a long-expected but so far experimentally unobserved fundamental process.

关键词： process. isomers excitation