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g.aranteed 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,g.aranteed cost attitude tracking.con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is ***,an aug.ented 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 desig.ed 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 reg.lation problem of the nominal aug.ented system,and a new hamilton-Jacobi-Bellman equation is ***,critic-only rein-forcement learning.alg.rithm with a concurrent learning.tech-nique is employed to solve the hamilton-Jacobi-Bellman equa-tion and obtain the optimal *** proposed alg.rithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety *** performance of the alg.rithm is evaluated by the numerical simulation.

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

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 Jing.i Tianjin Key Laboratory for Advanced Sig.al Processing Civil Aviation University of ChinaTianjin 300300China Colleg. of Electronic information and Automation Civil Aviation University of ChinaTianjin 300300China

Performance of non-line-of-sig.t(NLOS)ultraviolet(UV)communication is closely related with the communication rang.,system g.ometry and the atmosphere aerosol *** this paper,we investig.te the path loss of the NLOS UV ... 详细信息

关键词： communication properties. NLOS

A review of vehicle detection methods based on computer vision

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Journal of Intelligent and Connected Vehicles

Journal of intellig.nt and Connected Vehicles 2024年第1期7卷 1-18页

作者： Chang.i ma Fansong.Xue School of Traffic and Transportation Lanzhou Jiaotong UniversityLanzhou 730070China Key Laboratory of railway industry on Plateau railway Transportation intellig.nt manag.ment and Control Lanzhou 730070China

With the increasing.number of vehicles,there has been an unprecedented pressure on the operation and maintenance of intellig.nt transportation systems and transportation *** order to achieve faster and more accurate identification of traffic vehicles,computer vision and deep learning.technolog. play a vital role and have made sig.ificant *** study summarizes the current research status,latest finding.,and future development trends of traditional detection alg.rithms and deep learning.based detection *** the detection alg.rithms based on deep learning.this study focuses on the representative convolutional neural network ***,it examines the two-stag. and one-stag. detection alg.rithms,which have been extensively utilized in the field of intellig.nt transportation *** to traditional detection alg.rithms,deep learning.based detection alg.rithms can achieve hig.er accuracy and *** sing.e-stag. detection alg.rithm is more efficient for real-time detection,while the two-stag. detection alg.rithm is more accurate than the sing.e-stag. detection *** the follow-up research,it is important to consider the balance between detection efficiency and detection ***,vehicle missed detection and false detection in complex scenes,such as bad weather and vehicle overlap,should be taken into *** will ensure better application of the research finding. in eng.neering.practice.

关键词： intellig.nt transportation system computer vision deep learning vehicle detection object detection alg.rithm

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 Eng.neering 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 alg.rithm 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

Diag.ostic performance of dynamic contrast-enhanced mag.etic resonance imag.ng.parameters and serum tumor markers in rectal carcinoma prog.osis

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World Journal of g.strointestinal Oncolog. 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 radiolog. Yantai Mountain HospitalYantai 264001Shandong ProvinceChina Department of radiolog. Yantai Yuhuangding HospitalYantai 264000Shandong ProvinceChina Department of g.naecolog. Yantai Yuhuangding HospitalYantai 264000Shandong ProvinceChina The First Clinical Medical Colleg. Xinjiang Medical UniversityUrumqi 830011Xinjiang Uygur Autonomous RegionChina

BACKg.OUND Rectal carcinoma(RC),one of the most common malig.ancies g.obally,presents an increasing.incidence and mortality year by year,especially among.young.people,which seriously affects the prog.osis and quality of life of *** present,dynamic contrast-enhanced mag.etic resonance imag.ng.DCE-MRi)parameters and serum carbohydrate antig.n 19-9(CA19-9)and CA125 Levels have been used in clinical practice to evaluate the T stag. 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 stag. and differentiation deg.ee of *** To analyze the diag.ostic performance of DCE-MRi parameters combined with serum tumor markers(TMs)in assessing.patholog.cal processes and prog.osis of RC *** A retrospective analysis was performed on 104 RC patients treated at Yantai Yuhuang.ing.Hospital from may 2018 to January *** were categ.rized into stag.s T1,T2,T3,and T4,depending.on their T stag. and differentiation *** addition,they were assig.ed to low(L g.oup)and moderate-hig. differentiation(M+H g.oup)g.oups based on their differentiation *** levels of DCE-MRi parameters and serum CA19-9 and CA125 in different g.oups 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 stag.ng.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 stag.ng.was *** Ktrans,Ve,CA19-9 and CA125 were hig.er in the hig.-stag. g.oup and L g.oup than in the low-stag. g.oup and M+H g.oup,respectively(Pran and Ve parameters were 0.638 and 0.694 in the diag.osis of hig. and low stag.s,respectively,and 0.672 and 0

关键词： Rectal carcinoma Volume transfer constant rate constant Extravascular extracellular volume fraction Serum carbohydrate antig.n 19-9 Serum carbohydrate antig.n 125

A desig. scheme for interference suppression based on CWBiM

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Hig. Technolog. Letters 2024年第2期30卷 179-187页

作者：王蕴哲 ma Tianming.JiANg.Xiaoxiao ma Hong.ei School of Electrical and Electronic Eng.neering Shanghai University of Engineering ScienceShanghai 201620P.R.China

An interference suppression desig. scheme based on conjug.te weig.ted butterfly interleaving.mapping.CWBiM)is proposed for inter-carrier interference(iCi)and inter-subband interference(iBi)in the received sig.als 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)alg.rithm while maintaining.the orig.nal data transmission ***,conjug.te and complex weig.ting.operations can effectively suppress the impact of phase rotation errors in hig.-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 alg.rithm,the CWBiM-UFMC scheme proposed in this paper can effectively suppress iCi and iBi in the received sig.al without compromising.data transmission efficiency and reducing.computational complexity,thereby achieving.g.od 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： Zhig.o ma Yumiao Wang.Yi Yang.Youjing.Wang.Kai Zhao Yixin Li Chang.o Fu Wanbing.He Yug.ng.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 energ.,and-ray *** technolog.cal advances in hig.-intensity lasers have made it possible to excite or de-excite nuclear isomers using.table-top laser *** a particle-in-cell code,we investig.te the interaction of a laser with a nanowire array and calculate the production rates of the^(73m)g.(E_(1)=13.3 keV)and^(107m)Ag.E_(1)=93.1 keV)***^(73m1)g.,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 hig. 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

g.owth,optical dispersion and mag.etic behavior of Dy^(3+) doped yttrium iron g.rnet crystals

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Journal of rare Earths 2024年第6期42卷 1110-1117,I0004页

作者： Yating.Fang.Hui Shen Yudie ma Shijie Liao Shuang.Xia Tian Tian Ding.Zhou Yunfeng.ma Jiayue Xu institute of Crystal g.owth School of Materials Science and EngineeringShanghai Institute of Technology National Eng.neering.Center of Electromag.etic radiation Control materials School of Electronic Science and EngineeringUniversity of Electronic Science and Technology of China

Y_(3)Fe_(5)O_(12)(Yig.crystals are hig.ly desirable for the fabrication of mid-infrared isolators with the rapid g.owth of optical communications,althoug. it is rather challeng.ng.to g.ow larg. size and hig.-quality sing.e ***^(3+)doping.is expected to improve the optical and mag.eto-optical prope ***,hig. quality Dy:Yig.crystals and the adjustment of Dy^(3+)on the structure and optical behavior of Yig.crystal remain unclear,impeding.its practical ***,a series of Y_(3-x)Dy_(x)Fe_(5)O_(12)(x=0,0.5,1.0,1.5,3)solid solution crystals was g.own by the flux-Bridg.5}n method and sing.e crystals up to 25 mm were *** the introduction of Dy^(3+),lattice parameters are g.0}dually enlarg.d from 1.2379 nm(Yig.to 1.2420 nm(Dyig..Typical Dy^(3+)absorption peaks are observed around 1070,1265 and 1670 *** refractive index decreases from 2.37(500 nm)to 2.10(2500 nm)for Yig.crystal,and it reduces from 2.47(500 nm)to 2.16(2500 nm)for Dyig.*** optical bandg.ps remain almost unchang.d for Dy:Yig.*** optical dispersion of the refractive indices was finely fitted by the Wemple and DiDomenico(WDD)and the Sellmeier models,*** the increase of Dy^(3+)content,the saturation mag.etization(Ms)decreases sig.ificantly from 23.62 emu/g.Yig.to 5.33 emu/g.Dyig..Small coercive field is persisted for this system,endowing.small external mag.etic *** results provide valuable references for the manipulation of rare earths on the properties of mag.etooptical crystals,which is beneficial to the desig. of hig.-performance g.rnet crystals for the application of optical switching.and non-reciprocal related devices.

关键词： mag.eto-optical crystal Yttrium iron g.rnet Dy^(3+)doping Crystal g.owth Optical dispersion rare earths

Unravelling.the nature of the active species as well as the Mn doping.effect over g.mma-Al_(2)O_(3) catalyst for eliminating.AsH_(3) and PH_(3)

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Journal of Environmental Sciences 2024年第2期136卷 213-225页

作者： Bowen Xu Jiaxin Qu Xueqian Wang.Lang.ang.Wang.Yu Pu Ping.Ning.Yibing.Xie Yixing.ma Qiang.ma Faculty of Environmental Science and Eng.neering Kunming University of Science and TechnologyKunming 650500China School of Architecture and Civil Eng.neering Chengdu UniversityChengdu 610106China

To investig.te the enhancing.effect of Mn on the performance of simultaneous catalytic oxidation of AsH_(3)and PH_(3)by CuO-Al_(2)O_(3)in a reducing.atmosphere under micro-oxyg.n conditions,Cu-Mn modifiedγ-Al_(2)O_(3)catalysts were *** characteristics of the catalysts showed that Mn reduced the crystallinity of the active CuO component,increased the number of oxyg.n vacancies and acidic sites on the catalyst surface,enhanced the mobility of surface oxyg.n,and the interaction between copper and mang.nese promoted the redox cycling.ability of the catalysts and improved their oxidation performance,which increased the conversion frequency(TOF)by 2.54×10^(-2)to 3.07×10^(-2)sec^(-1).On the other hand,the introduction of Mn reduced the production of phosphate and As_(2)O_(3)on the catalyst surface by30.96%and 44.9%,which reduced the coverag. and inerting.of the active sites by phosphate and As_(2)O_(3),resulting.in an 8 hr(6 hr)improvement in the stability of PH_(3)(AsH_(3))removal.

关键词： AsH_(3)-PH_(3)removal Oxyg.n activation Mn doping Stability enhancement