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Monocular 3D object detection with Pseudo-LiDAR confidence sampling and hierarchical geometric feature extraction in 6g network

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Digital Communications and Networks 2023年第4期9卷 827-835页

作者： Jianlong Zhang guangzu Fang Bin Wang Xiaobo zhou Qingqi Pei Chen Chen School of Electronic Engineering Xidian UniversityXi'an710071China School of Computer Science and Technology College of Intelligence and ComputingTianjin UniversityTianjin300000China School of Telecommunications Engineering Xidian UniversityXi'an710071China

The high bandwidth and low latency of 6g network technology enable the successful application of monocular 3D object detection on vehicle *** 3D-object-detection-based Pseudo-LiDAR is a low-cost,lowpower solution compared to LiDAR solutions in the field of autonomous ***,this technique has some problems,i.e.,(1)the poor quality of generated Pseudo-LiDAR point clouds resulting from the nonlinear error distribution of monocular depth estimation and(2)the weak representation capability of point cloud features due to the neglected global geometric structure features of point clouds existing in LiDAR-based 3D detection ***,we proposed a Pseudo-LiDAR confidence sampling strategy and a hierarchical geometric feature extraction module for monocular 3D object *** first designed a point cloud confidence sampling strategy based on a 3D gaussian distribution to assign small confidence to the points with great error in depth estimation and filter them out according to the ***,we present a hierarchical geometric feature extraction module by aggregating the local neighborhood features and a dual transformer to capture the global geometric features in the point ***,our detection framework is based on Point-Voxel-RCNN(PV-RCNN)with high-quality Pseudo-LiDAR and enriched geometric features as *** the experimental results,our method achieves satisfactory results in monocular 3D object detection.

关键词： Monocular 3D object detection Pseudo-LiDAR Confidence sampling Hierarchical geometric feature extraction

Backward automatic calibration for three-dimensional landslide models

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geoscience Frontiers 2021年第1期12卷 231-241页

作者： giacomo Titti giulia Bossi gordon g.D.zhou gianluca Marcato Alessandro Pasuto DICAM-UNIBO Department of CivilChemicalEnvironmental and Materials EngineeringAlma Mater Studiorum University of BolognaViale Risorgimento 2Bologna40136Italy IRPI-CNR Research Institute for Geo-Hydrological ProtectionNational Research CouncilC.so Stati Uniti4Padova35127Italy IMHE-CAS Key Laboratory of Mountain Hazards and Earth Surface Process/Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesBlock 4Renminnanlu RoadChengdu610041China

Back-analysis is broadly used for approaching geotechnical problems when monitoring data are available and information about the soils properties is of poor *** landslide stability assessment back-analysis calibration is usually carried out by time consuming trial-and-error *** paper presents a new automatic Decision Support System that supports the selection of the soil parameters for three-dimensional models of landslides based on monitoring *** method considering a pool of possible solutions,generated through permutation of soil parameters,selects the best ten configurations that are more congruent with the measured *** reduces the operator biases while on the other hand allows the operator to control each step of the *** final selection of the preferred solution among the ten best-fitting solutions is carried out by an *** operator control is necessary as he may include in the final decision process all the qualitative elements that cannot be included in a qualitative analysis but nevertheless characterize a landslide dynamic as a whole epistemological subject,for example on the base of geomorphological evidence.A landslide located in Northeast Italy has been selected as example for showing the system *** proposed method is straightforward,scalable and robust and could be useful for researchers and practitioners.

关键词： Automatic landslide modelling FLAC3D~(TM) Back-analysis Optimization Decision Support System

Different Warming Patterns of Tropical Pacific Sea Surface Temperature Projected by FgOALS-g2 and FgOALS-s2 under RCP8.5

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Atmospheric and Oceanic Science Letters 2015年第2期8卷 82-87页

作者： ZhaNg Li-Xia zhou Tian-Jun State Key Laboratory of Numerical Modeling for Atmospheric Sciences and geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology Joint Center for global Change Studies (JCgCS)

The different patterns of SST changes under the ＋8.5 W m 2 Representative Concentration Pathway （RCP8.5） projected by the latest two versions of the Flexible global Ocean-Atmosphere-Land System model （FgOALS-g2 and FgOALS-s2; grid-point version 2 and spectral version 2, respectively）, and the potential mecha- nisms for their formation are studied in this paper. The results show that, although both FgOALS-g2 and FgOALS-s2 project global warming patterns, FgOALS-g2 （FgOALS-s2） projects a La Nifia-like （an E1 Nifio-like） mean warming pattern with weakest （strongest） warming over the central （eastern） equatorial Pacific for 2081-2100 relative to 1986-2005 under RCP8.5. A mixed layer heat budget analysis shows that the projected tropical Pacific Ocean warming in both models is primarily caused by atmos- pheric forcing. The main differences in the heating terms contributing to the SST changes between the two models are seen in the downward longwave radiation and ocean forcing. The minimum SST warming over the equatorial Pacific in FgOALS-g2 is attributed to the local minimum heating of downward longwave radiation and maximum cooling of ocean forcing. In contrast, the maximum SST warming over the equatorial Pacific in FgOALS-s2 is due to the maximum warming of downward longwave radia- tion, and the contribution of ocean forcing is minor. The minimum SST warming over the equatorial Pacific in FgOALS-g2 emerges around the 2050s, before when the SST over the equatorial Pacific is warmer than that over the extra-equatorial Pacific. In FgOALS-s2, the SST dif- ference shows a continuous increasing trend for 2006- 2100. Further examination of the oceanic and atmospheric circulation changes is needed to reveal the process responsible for the longwave radiation and ocean forcing difference between the two models.

关键词： climate model SST projection heat budget

harmful effects of pyrethroid ester insecticide on the male reproductive system mainly through affecting testicular function and inflammatory markers

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BIOCELL 2020年第1期44卷 111-115页

作者： ha ABDEL MAKSOUD Mk MAHFOUZ Mi SOLIMAN Mohamed g ELhaRRIF M ABBASS Ma EL-BADRY Department of Biochemistry Benha UniversityBenhaEgypt Department of Basic Medical Sciences Shaqra UniversityShaqraaSaudi Arabia

Pyrethroid esters are widely used as insecticides worldwide. In this study, we aimed to evaluate the harmful effect of deltamethrin on the male reproductive system through the assessment of reproductive hormones, inflammatorymarkers, and testicular function. To achieve our aim, eighty male 7-9-week-old, Wistar rats were taken, weighed, and divided into four experimental groups. The first group was kept as a control group, and the other three groups were given deltamethrin orally at different concentrations (0.87, 8.7, and 17.4 mg/kg body weight) for nine weeks. The resultsindicated that deltamethrin administration associated with a significant decrease in reproductive hormones, especially FSH, LH, and significant elevation in the interleukin 2 (IL2), interleukin 6 (IL6), histamine, and cortisol levels. Also, thesignificance of inhibition of sperm motility and viability, decreased testis weights, sperm count, and fructose in semen were noted. These findings clarify the harmful effect of deltamethrin on the male reproductive system by producing a significant alteration in reproductive hormones, inflammatory markers as well as testicular function.

关键词： Deltamethrin Reproductive hormones Inflammatory markers

Effect of scanning strategy on grain structure and crystallographic texture of Inconel 718 processed by selective laser melting

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Journal of Materials Science & Technology 2018年第10期34卷 1799-1804页

作者： H.Y. Wan Z.J. zhou C.P. Li g.F. Chen g.P. Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China Materials & Manufacturing Qualification group Corporate Technology Siemens Ltd. Beijing 100102 China

Two types of scanning strategies were adopted to study the effect of scanning strategy on grain structure and crystallographic texture of selective laser melted （SLM） Inconel 718. The results show that bidirec-tional scanning without and with a 90°-rotation for every layer produced the bimodal grain structure and the directional columnar grain structure, respectively. Controlling the heat flux direction between the successive layers via scanning strategy enabled the formation of such different grain structures. Fur-thermore, when the 90°-rotation was applied, the competitive grain growth mechanism became more pronounced and the strong cube texture developed.

关键词： Selective laser melting Additive manufacturing Scanning strategy Texture grain structure

Significantly Enhanced Performance of g-C3N4/Bi2MoO6 Films for Photocatalytic Degradation of Pollutants Under Visible-light Irradiation

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Chemical Research in Chinese Universities 2016年第2期32卷 284-290页

作者： LIU Yujun zhou Feng ZhaN Su YANg Yifan YIN Yanfeng Transportation Equipment and Ocean Engineering College Dalian Maritime University Dalian 116026 P. R. China

The films of photocatalysts have been widely used in decomposition pollutants. In this study, the films were successfully prepared from Bi2MoO6 and g-C3N4/Bi2MoO6 by a simple method, respectively. The samples were characterized by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, Fourier transform infrared spectroscopy（FTIR）, photoluminescence（PL）, UV-Vis diffuse reflectance spectroscopy（DRS） and electrochemical experiments to investigate crystalline structure, morphology, composition and properties. The photocatalytic activity of the photocatalyst films for the pollutants was evaluated by degradation of methylene blue（MB） in aqueous solution under visible light irradiation. Experiments revealed that the film of g-C3Na/Bi2MoO6 exhibited higher photocatalytic ability compared to the single-component photocatalyst, and proved its stability. The superior catalytic performance can be attributed to the effective separation of electron-hole pairs and the reduced rate of recombination. This work is of great value for the preparation of photocatalysts films.

关键词： Film g-C3N4 Bi2MoO6 Photocatalyst

A dual-beam piezo-magneto-elastic wake-induced vibration energy harvesting system for high-performance wind energy harvesting

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Science China(Technological Sciences) 2024年第1期67卷 221-239页

作者： MA XiaoQing ZhaNg hang MARgIELEWICZ Jerzy gĄSKA Damian WOLSZCZAK Piotr LITAK grzegorz zhou ShengXi School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Research&Development Institute in Shenzhen Northwestern Polytechnical UniversityShenzhen 518057China Faculty of Transport and Aviation Engineering Silesian University of TechnologyKrasińskiego 8Katowice 40-019Poland Department of Automation Lublin University of TechnologyNadbystrzycka 36Lublin 20-618Poland

Wind-induced vibration energy harvesting has a great potential for utilizing wind energy to supply power for low-powered *** improve the working performance of energy harvesters effectively,a suitable structural design is *** paper proposes a dual-beam piezo-magneto-elastic wake-induced vibration energy harvesting system to enhance the functional performance of aeroelastic energy harvesters in environments with variable wind *** system contains two piezoelectric beams coupled by magnets(forming upstream and downstream energy harvesters),and each beam is attached with a foam cylinder.A corresponding dynamic model is provided,and output characteristics are obtained at different wind *** and experimental verification indicate that both upstream and downstream energy harvesters can realize efficient energy *** the wind speed exceeds a certain critical value,the amplitudes of the system’s displacement and voltage are *** wind speed threshold value is approximately 1.25 m/*** the wind speed and magnet spacing are 10.2 m/s and 20 mm,respectively,the output power of the system reaches 4.9×10^(−4)***,the wind speed threshold value of the proposed system can be adjusted by an equivalent nonlinear restoring force.

关键词： dual-beam structure piezoelectric energy harvester theoretical model nonlinear dynamics

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Debris flow impact on flexible barrier: effects of debrisbarrier stiffness and flow aspect ratio

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Journal of Mountain Science 2019年第7期16卷 1629-1645页

作者： SONg Dong-ri zhou gordon g.D CHOI Clarence Edward ZHENg Yun Key Laboratory of Mountain hazards and Earth Surface Process/Institute of Mountain hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China Department of Civil and Environmental Engineering Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina The HKUST Jockey Club Institute for Advanced Study Hong Kong SARChina

Conventionally,flexible barriers are rated based on their ability to resist a free-falling boulder with a particular input ***,there is still no well-accepted approach for evaluating performance of flexible barrier under debris flow *** this study,a large-nonlinear finite-element model was used to back-analyze centrifuge tests to discern the effects of impact material type,barrier stiffness,and flow aspect ratio(flow height to flow length)on the reaction force between the impacting medium and flexible *** show that,in contrast to flexible barriers for resisting rockfall,the normal impact force induced by the highly frictional and viscous debris is insensitive to barrier *** is because the elongated distributions of kinetic energy are mainly dissipated by the internal and boundary shearing,and only a small portion is forwarded to the ***,a new stiffness number is proposed to characterize the equivalent stiffness between a debris flow or a boulder,and a flexible *** the circumstance of an extremely elongated debris flow event,i.e.,low aspect ratio,the load on a barrier is dominated by the static component and thus not sensitive to the barrier stiffness.

关键词： Debris flow Flexible barrier Impact Stiffness Flow aspect ratio

Red Emission of Eu（lll） Complex Based on 1-（7-（ferf-butyl）-g-ethyl-gH- carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione Excited by Blue Light

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Chinese Journal of Chemical Physics 2012年第6期25卷 697-702,I0004页

作者： Sheng-gui Liu Wen-yi Su Rong-kai Pan Xiao-ping zhou School of Chemistry Science and Technology Zhanjiang Normal University Zhanjiang 524048 China

A new Eu（III） complex, EuL3（phen）, was synthesized, where L is the abbreviation of de- protonated 1-（7-（tert-butyl）-9-ethyl-gH-carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione （HL）, phen is the abbreviation of 1,10-phenanthroline. The Eu（III） complex was characterized by element analysis, IR, 1H NMR, UV-visible absorption spectroscopy, thermogravimetric anal- ysis （TgA）, and photoluminescence measurements （PL）. TgA shows that thermal stability of the complex is up to 325 ~C. PL measurement indicates that the Eu（III） complex exhibits intense red-emission and extends their excitation bands to visible region. LEDs device was successfully fabricated by precoating complex EuL3 （phen） onto 460 nm blue-emitting IngaN chip. The emission of device shows that the complex can act as red phosphor in combination with 460 nm blue-emitting chips. This europium complex based on 1-（7-（tert-butyl）-9- ethyl-9H-carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione is a kind of interesting red-emitting material excited by blue light, which could avoid the damage of excitation by UV light.

关键词： Carbazole fl-diketone Lanthanide complex Chemical synthesis Luminescence