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YOLO-Drone:A Scale-Aware Detector for Drone Vision

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Chinese Journal of Electronics 2024年第4期33卷 1034-1045页

作者： Yutong LI Miao MA Shichang LIU chao yao Longjiang GUO School of Computer Science Shaanxi Normal University Key Laboratory of Modern Teaching Technology Ministry of Education College of Computer Science Sichuan University

Object detection is an important task in drone vision. Since the number of objects and their scales always vary greatly in the drone-captured video, small object-oriented feature becomes the bottleneck of model performance, and most existing object detectors tend to underperform in drone-vision scenes. To solve these problems, we propose a novel detector named YOLO-Drone. In the proposed detector, the backbone of YOLO is firstly replaced with ConvNeXt, which is the state-of-the-art one to extract more discriminative features. Then, a novel scale-aware attention(SAA) module is designed in detection head to solve the large disparity scale problem. A scale-sensitive loss(SSL) is also introduced to put more emphasis on object scale to enhance the discriminative ability of the proposed detector. Experimental results on the latest VisDrone 2022 test-challenge dataset(detection track) show that our detector can achieve average precision(AP) of 39.43%, which is tied with the previous state-of-the-art, meanwhile,reducing 39.8% of the computational cost.

关键词： YOLO Costs Object oriented modeling Computational modeling Detectors Feature extraction Data models

RELATIONSHIP OF FIRST STEP HEIGHT,STEP SLOPE AND CAVITY IN X-SHAPED FLARING GATE PIERS

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Journal of Hydrodynamics 2007年第3期19卷 349-355页

作者： WANG Bo WU chao HU yao-hua MO Zheng-yu State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China.

The energy dissipation of X-shaped flaring gate piers ahead of a stepped spillway was adopted in the Suofengying Hydroplant. Under the circumstance that the first step is higher than others, at the step surface an aerated cavity occured behind piers. The interaction of the weir head, the elevation difference between crest and chamber outlet, the first step height, the slopes of weir end and step, and the size of cavity, was investigated, the expression was derived to characterize their relationship, and the corresponding curves were plotted. The comparison of the calculated and simulated results with the measured data was performed. When the slopes of step and weir end are equivalent, the relative height difference between the first and second steps becomes the main factor influencing the aerated cavity. These findings may be useful in practical applications.

关键词： X-shaped flaring gate pier first step height slope of weir end step slope size of cavity

Solid-liquid phase change materials microcapsules: Synthesis strategies,thermal storage and beyond

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Progress in Natural Science:Materials International 2024年第4期34卷 615-631页

作者： Yan Gao Huan Liu Haoguan Gui chao yao Guolin Zhang Fuxin Liang Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology School of Petrochemical Engineering Changzhou University Department of Chemical Engineering Tsinghua University Liaoning Provincial Key Laboratory for Green Synthesis and Preparative Chemistry of Advanced Materials Liaoning University

Thermal energy storage is crucial in the context of achieving carbon neutrality. Phase change latent heat stands out among various thermal storage methods due to the high energy density of phase change materials(PCMs).PCMs possess unique characteristics such as tunable thermal storage or/and release processes, constant phasetransition temperatures, and changes in physical state. However, solid-liquid PCMs cannot be directly utilized due to the liquid leakage in their melted state. The encapsulation of PCM microcapsules(PCMMs) is essential for overcoming limitations and optimizing functionalities of the PCMs. Encapsulation strategies play a key role in considering factors like morphology, structure, physicochemical properties, and specific applications. Furthermore, PCMMs can expand their potential applications by incorporating functional nano-materials within their shells or introducing specific components into their cores during the synthesis process. This review examines various encapsulation strategies for PCMMs, including physical, physicochemical, and chemical methods. Various applications of PCMMs are summarized and analyzed with regards to the characteristics of PCMs in thermal storage, temperature control, and state transformation. Furthermore, the reinforcement strategies or/and design considerations of PCMMs are crucial for meeting specific requirements, such as conventional latent heat storage,thermal protection, and thermal-triggered intelligent materials. Finally, it discusses current challenges, proposed solutions, and future research directions in the field of PCMMs, particularly Janus particle modified PCMMs.

关键词： Phase change materials Microcapsule Controllable synthesis Programmable mechanical behavior Controlled payload release

Effects of Aluminum Doping on the Microstructure and Electrical Properties of ZnO- Pr_6O_(11)-Co_3O_4-MnCO_3-Y_2O_3 Varistor Ceramics

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Journal of Wuhan University of Technology(Materials Science) 2014年第2期29卷 246-249页

作者：王茂华 ZHANG Bo LI Gang yao chao School of Chemistry and Chemical Engineering Changzhou University Jiangsu Province Key Laboratory of Fine Petrochemical Industry

Abstract： The effect of Al_2O_3 doping on the microstructure and electrical properties of the ZnO- Pr_6O11-CO_3O_4-MnCO_3-Y_2O_3 system was investigated in the range of 0.0-0. lmol%. The results reveal that Al_2O_3 doping has slight influence on the densification process. The microstructure of the ceramics comprises of ZnO phase, ZnAl_2O_4 spine phase and Pr-rich phases. The addition of Al_2O_3 greatly affects the electrical properties. The varistor voltage （E_1mA/cm^2） of ZPCMYAl samples decreases over a wide range from 5 530 V/cm to 1 844 V/cm with the increasing Al_2O_3 content. The nonlinear exponent（a） increases with the increasing Al_2O_3 content to 0.01mol%, whereas it is decreased by the further doping. The ZPCMYAI-based varistor ceramics with 0.01mol% Al_2O_3 exhibit the best electrical properties, with the nonlinear exponent （ct） attaining the highest value of 33.4 and the lowest leakage current of 2.7 μA. The capacitance-voltage （C-V） measurement shows that the donor density （Nd） at the grain boundaries increase from 1.58×10^18 to 3.15×10^18 cm^-3, the barrier height （Чb） increases from 1.60 to 2.36 eV, and the depletion layer width （t） decreases from 24.9 to 21.6 nm.

关键词： microstructure electrical properties Al_2O_3 doping varistors

A systematic evaluation of computational methods for predicting translated non-canonical ORFs from ribosome profiling data

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Journal of Genetics and Genomics 2024年第1期51卷 105-108页

作者： Tianyu Lei Yue Chang chao yao Hong Zhang College of Ecology Lanzhou UniversityLanzhouGansu 730000China Cuiying Honors College Lanzhou UniversityLanzhouGansu 730000China

Ribosome profiling(Ribo-Seg)enables genome-wide survey of translational activities at nucleotide resolution by enriching and sequencing ribosome-protected fragments(RPFs)in the cell(Ingolia et al.,2009).Based on the characteristic distribution of RPFs in Ribo-Seq,such as enrichment in open reading frames(ORFs)and three-nucleotide periodicity,many computational methods have been developed to detect translated ORFs from Ribo-Seq data(Wang et al.,2020a).

关键词： translated enable canonical

Review on effect of applied internal cooling source and vibration on metal solidification process

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Journal of Iron and Steel Research International 2023年第6期30卷 1059-1072页

作者： Yu-chao yao Miao Liu Zhong-qiu Liu Bao-kuan Li Yong Gan Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina China Iron&Steel Research Institute Group Co. Ltd.Beijing 100081China

Advancements in metallurgical technology have led to the emergence of high-performance requirements for metal materials,like high uniformity,high purity,and superfine *** has resulted in the development and application of internal cooling source(ICS),vibrational,and vibrational internal cooling source methods in metal solidification processes to afford products with refined crystal grains and large proportions of equiaxed *** methods have gradually been introduced into laboratories and some steel mills over the past few ***,there are few successful industrial applications of these methods,as there is no comprehensive understanding of their control theories and ***,the development,basic principles,and classifications of the three types of methods are summarized,and their impact on the solidification of molten metals and the morphology of solid products is *** addition,experimental and numerical simulation-based researches on each type of method are reviewed and their prospects for applications are briefly discussed to control metal ***,detailed future perspectives are provided on vibratory strip feeding,ICS,and pulsed magneto-oscillation ***,it will serve as a reference for future studies of the application of these and related methods in metal solidification processes.

关键词： Internal cooling source Vibration Solidification Strip feeding Grain refinement

Construction of spinel/biochar film/honeycomb monolithic catalyst for photothermal catalytic oxidation of VOCs

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 61-71页

作者： Xikai Lu Chunyan Zhang Meng Wu Wenjie Liu Bin Xue chao yao Xiazhang Li National-Local Joint Engineering Research Center of Biomass Refining and High-quality Utilization Changzhou UniversityChangzhou 213164China Department of Materials Science and Engineering University of DelawareDelaware CityDE 19716USA

Photothermal catalytic oxidation emerges as a promising method for the removal of volatile organic compounds(VOCs).Herein,via sol-gel impregnation method,spinel CuMn_(2)O_(4)was coated on attapulgite honeycombs with integrating biochar(BC)film as the second carrier,using chestnut shell as complexation *** mass ratios of CuMn_(2)O_(4)to chestnut shell was modulated to investigate the catalytic toluene degradation *** indicated that the monolithic CuMn_(2)O_(4)/BC/honeycomb catalyst demonstrated superior photothermal catalytic toluene degradation with a low T90(temperature at 90%degradation)of 263℃ when the mass ratio of CuMn_(2)O_(4)to biomass was 1:*** addition of BC film substantially increased the honeycomb's specific surface area and improved the photothermal conversion of spinel,leading to enhanced photothermal catalytic *** study presents a cost-effective strategy for eliminating industrial VOCs using clay-biomass based monolithic catalyst.

关键词： CuMn_(2)O_(4) biochar photothermal catalysis attapulgite honeycomb volatile organic compound

La1-xCexMnO3/attapulgite nanocomposites as catalysts for NO reduction with NH3 at low temperature

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Particuology 2016年第3期14卷 66-72页

作者： Xiazhang Li YU Yin chao yao Shixiang Zuo Xiaowang Lu Shiping Luo chaoying Ni fiangsu Key Laboratory of Advanced Catalytic Materials and Technology School of Petrochemical Engineering Changzhou University Changzhou 213164 China R&D Center of Xuyi Attapulgite Applied Technology Chinese Academy of Sciences Xuyi 211700 China W. M. Keck CenterforAdvanced Microscopy and Microanalysis University of Delaware Newark DE 19716 USA

A series of attapulgite （ATP） supported perovskite-type La1-xCexMnO3 ix=0-0.2） nanocomposites were prepared by a sol-gel method. The samples were characterized by X-ray diffraction, transmission elec- tron microscopy, Fourier-transform infrared spectroscopy, H2 temperature-programmed reduction, and temperature-programmed desorption of NH3. Their selective catalytic reduction of NO with NH3 was evaluated in the low-temperature range. The impact of the doping fraction of Ce4＋ on the NO conversion was investigated. The results indicated that the La1-xCexMnO3 nanoparticles with a size of ca. 15 nm were uniformly immobilized on the surface of ATP with a loading amount of 20wt%. The highest conversion rate of NO reached 98.6% when the doping fraction x was O.1, while the ATP support supplied a high surface areas facilitating the nanoparticles dispersion as well as the gas adsorption. Incorporation of an appropriate amount of Ce4＋ in the La3＋ site resulted in a high degree of reduction by the active perovskite species with enhanced catalytic activity.

关键词： Attapulgite Rare earth perovskite Nanocomposite Selective catalytic reduction NO conversion

Analytical Modeling of Dual Material Gate SOI MOSFET with Asymmetric Halo

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Journal of China University of Mining and Technology 2006年第3期16卷 308-311页

作者： LI Zun-chao JIANG yao-lin ZHANG Li-li School of Electrical and Communication Engineering Xi＇an Jiaotong University Xi＇an Shanxi 710049 China

A dual material gate silicon-on-insulator MOSFET with asymmetrical halo is presented to improve short channel effect and carder transport efficiency for the first time. The front gate consists of two metal gates with different work functions by making them contacting laterally, and the channel is more heavily doped near the source than in the rest. Using a three-region polynomial potential distribution and a universal boundary condition, a two-dimensional analytical model for the fully depleted silicon-on-insulator MOSFET is developed based on the explicit solution of two-dimensional Poisson＇s equation. The model includes the calculation of potential distribution along the channel and subthreshold current. The performance improvement of the novel silicon-on-insulator MOSFET is examined and compared with the traditional silicon-on-insulator MOSFET using the analytical model and two-dimensional device simulator MEDICI. It is found that the novel silicon-on-insulator MOSFET could not only suppress short channel effect, but also increase cartier transoort efficiency noticeably. The derived analytical model agrees well with MEDICI.

关键词： SOI MOSFET dual material gate subthreshold current surface potential