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基于改进YOLOv8的自动驾驶场景目标检测算法

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计算机工程与应用 2025年第1期61卷 131-141页

作者：杨磊陈艳菲李海鸣石教兴安培武汉工程大学光学信息与模式识别湖北省重点实验室武汉430205 武汉工程大学电气信息学院武汉430205 华中科技大学电子信息与通信学院武汉430074

针对自动驾驶场景遮挡目标和小目标检测困难问题,提出了FAN-YOLOv8n自动驾驶检测算法。设计了特征感受野融合模块(EFFVM),增强模型主干部分对局部特征的提取,提高模型对遮挡目标的检测能力;在模型头部增加了更浅特征层P2的检测头,提高... 详细信息

针对自动驾驶场景遮挡目标和小目标检测困难问题,提出了FAN-YOLOv8n自动驾驶检测算法。设计了特征感受野融合模块(EFFVM),增强模型主干部分对局部特征的提取,提高模型对遮挡目标的检测能力;在模型头部增加了更浅特征层P2的检测头,提高模型对于小目标的检测效果;在模型颈部设计了特征指导模块(FGM)来融合浅层和深层的特征信息,使得两层之间能够更好地进行特征交互,让模型更关注细粒特征。提出了特征层融合模块(FLFM),融合多尺度特征层并进行特征增强,使模型能够自适应不同尺度目标的检测。实验结果表明,在SODA10M数据集和部分BDD100K数据集上,改进模型的mAP0.5对比原始YOLOv8n模型提升了7个百分点和6.5个百分点,适用于实际自动驾驶检测任务。

关键词：自动驾驶 YOLOv8n 小目标遮挡目标

Optimizing 2D-metal contact in layered Tin-selenide via native oxide modulation

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Nano Research 2024年第4期17卷 3014-3020页

作者： Yue Zheng Qi you Zhentian Yin Jian Tang Ke Jiang Zihao Xie Henan li Cheng Han Yumeng shi International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060China College of Electronics and Information Engineering Shenzhen UniversityShenzhen 518060China

The discovery of two-dimensional(2D)semiconductor has opened up new avenues for the development of short-channel field-effect transistors(FETs)with desired electrical *** them,orthorhombic tin-selenide(SnSe)has garnered increasing attention due to its potential applications in a variety of electronic,optoelectronic,and thermoelectric ***,the realization of high-performance SnSe FETs with low contact resistance(Rc)remains a ***,we systematically investigate the contact of few-layer SnSe FETs through the modulation of native oxide on SnSe by using different *** is found that chromium(Cr)-contacted devices possess the best FET performance,such as electron mobility up to 606 cm^(2)/(V·s)at 78 K,current on/off ratio exceeding 1010,and saturation current of~550μA/μm,where a negligible Schottky barrier(SB)of~30 meV and a low contact resistance of~425Ωμm are achieved.X-ray photoelectron spectroscopy(XPS)and cross-sectional electron dispersive X-ray spectroscopy(EDX)results further reveal that the improved contact arises from the Cr-induced reduction of native oxide(SnOx)to Sn,which thins the tunneling barrier for efficient electron *** findings provide a deep insight into the 2D-metal contact of SnSe and pave the way for its applications in future nanoelectronics.

关键词： few-layer SnSe field-effect transistors(FETs) Cr contact native oxide contact resistance(Rc) Schottky barrier(SB)

GAMETOPHYTIC FACTOR 1,Involved in Pre-mRNA Splicing,Is Essential for Megagametogenesis and Embryogenesis in Arabidopsis

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Journal of Integrative Plant Biology 2009年第3期51卷 261-271页

作者： Man liu li Yuan Nai-you liu Dong-Qiao shi Jie liu Wei-Cai Yang Key Laboratory of Molecular and Developmental Biology National Center for Plant Gene Research Institute of Genetics and Developmental Biology the Chinese Academy of Sciences Beijing 100101 China Graduate University the Chinese Academy of Sciences Beijing 100049 China

RNA biogenesis is essential and vital for accurate expression of genes. It is obvious that cells cannot continue normal metabolism when RNA splicing is interfered with. sgt13018 is such a mutant, with partial loss of function of GAMETOPHYTIC FACTOR 1 （GFA1）; a gene likely involved in RNA biogenesis in Arabidopsis. The mutant is featured in the phenotype of diminished female gametophyte development at stage FG5 and is associated with the arrest of early embryo development in Arabidopsis. Bioinformatics data showed that homologs of gene GFA1 in yeast and human encode putative U5 snRNPspecific proteins required for pre-mRNA splicing. Furthermore, the result of yeast two-hybrid assay indicated that GFA1 physically interacted with AtBrr2 and AtPrp8, the putative U5 snRNP components, of Arabidopsis. This investigation suggests that GFA1 is involved in mRNA biogenesis through interaction with AtBrr2 and AtPrp8 and functions in megagametogenesis and embryogenesis in plant.

关键词： embryogenesis female gametophyte pre-mRNA splicing U5 snRNA complex.

Application of land use regression for estimating concentrations of major outdoor air pollutants in Jinan, China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第11期11卷 857-867页

作者： li CHEN shi-yong DU Zhi-peng BAI Shao-fei KONG Yan you Bin HAN Dao-wen HAN Zhi-yong li College of Environmental Science and Engineering Nankai University Tianjin 300071 China State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution and Control Tianjin 300071 China College of Urban and Environmental Science Tianjin Normal University Tianjin 300387 China Jinan Institute of Environmental Sciences Jinan 250014 China

SO2, NO2, and PM10 are the major outdoor air pollutants in China, and most of the cities in China have regulatory monitoring sites for these three air pollutants. In this study, we developed a land use regression (LUR) model using regulatory monitoring data to predict the spatial distribution of air pollutant concentrations in Jinan, China. Traffic, land use and census data, and meteorological and physical conditions were included as candidate independent variables, and were tabulated for buffers of varying radii. SO2, NO2, and PM10 concentrations were most highly correlated with the area of industrial land within a buffer of 0.5 km (R2=0.34), the distance from an expressway (R2=0.45), and the area of residential land within a buffer of 1.5 km (R2=0.25), respectively. Three multiple linear regression (MLR) equations were established based on the most significant variables (plied to an area with complex terrain. The buffer radii of independent variables for SO2, NO2, and PM10 were chosen to be 0.5, 2, and 1.5 km, respectively based on univariate models. Intercepts of MLR equations can reflect the background concentrations in a certain area, but in this study the intercept values seemed to be higher than background concentrations. Most of the cities in China have a network of regulatory monitoring sites. However, the number of sites has been limited by the level of financial support available. The results of this study could be helpful in promoting the application of LUR models for monitoring pollutants in Chinese cities.

关键词： Land use regression (LUR) Air pollution Background concentration Geographic information system (GIS)

Expression of regulating apoptosis gene and apoptosis index in primary liver cancer

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World Journal of Gastroenterology 2000年第5期6卷 721-724页

作者： Hong Yu Xu you lin Yang Xi li Guan Guang Song Ai Min Jiang li Jun shi Department of Digestion The First Hospital of Harbin Medical UniversityHarbin 150001China Department of Pathology The First Hospital of Harbin Medical UniversityHarbin 150001China

INTRODUCTIONProgramed cell death plays an important role in thegenesis of *** cancer genes canregulate ***,several proteins thatare structurally related to Bcl-2,an inhibitor ofapoptosis,have been ***,novel strategies... 详细信息

关键词： liver neoplasms apoptosis immunohistochemistry oncogenes tumor markers biological in situ hybridization

Myocarditis as an extraintestinal manifestation of ulcerative colitis:A case report and review of the literature

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World Journal of Clinical Cases 2022年第27期10卷 9750-9759页

作者： you-Yang Wang Wen shi Jian Wang Yue li Zhuang Tian Yang Jiao Department of General Internal Medicine Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Gastroenterology Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Radiology Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Cardiology and International Medical Service Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

BACKGROUND Although extraintestinal manifestations of inflammatory bowel disease(IBD) are well documented,myocarditis has only rarely been reported as an extraintestinal manifestation,and it can be *** various clinical presentations and causes of myocarditis in IBD patients complicate making a correct and timely *** SUMMARY Here we report a 15-year-old boy who presented with myocarditis as the initial presentation of a relapse of ulcerative *** reviewing the literature for cases of myocarditis complicating IBD,we found 21 other cases,allowing us to expand our understanding of the clinical presentation,diagnosis,management,and outcomes of this rare *** most frequent diagnostic clues for myocarditis in IBD patients are dyspnea,chest pain,tachycardia,raised cardiac biomarkers,and abnormalities on trans-thoracic ***,we discuss the etiology of myocarditis in IBD patients,which include an extraintestinal manifestation,the adverse effects of mesalamine and infliximab,selenium deficiency,and infection,to help provide a framework for diagnosis and *** Myocarditis as an extraintestinal manifestation of IBD can be ***-thoracic echocardiogram and cardiac magnetic resonance may assist its diagnosis.

关键词： Inflammatory bowel disease Myocarditis Ulcerative colitis Crohn’s disease Extraintestinal manifestation Case report

Automatic estimation of traveltime parameters in VTI mediausing similarity-weighted clustering

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Petroleum Science 2020年第2期17卷 363-375页

作者： shi-you liu Ying-Zhao Zhang Chao li Wan-Yuan Sun Gang Fang Guo-Chang liu Zhanjiang Branch China National Offshore Oil Corporation Ltd.Zhanjiang 524000GuangdongChina State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China Key Laboratory of Marine Hydrocarbon Resources and Environmental Geology Ministry of Land and ResourcesQingdao Institute of Marine GeologyChina Geological SurveyQingdao 266071ShandongChina

Compared with hyperbolic velocity estimation methods,nonhyperbolic methods(such as shifted hyperbola)are better choices for large offsets or vertical transverse isotropy(VTI)*** local seismic event slope contains subsurface information,they can be used to estimate zero-offset two-way traveltime and normal moveout *** traditional velocity estimation methods require a great deal of manual work and are also prone to human *** order to estimate the traveltime parameters for VTI media automatically,in this paper,we propose to use predictive painting and similarity-weighted clustering to obtain traveltime *** predictive painting is used to estimate zero-offset two-way traveltime,and the shifted-hyperbola traveltime equation is used to obtain velocity and anisotropy *** first map local slopes to zero-offset two-way traveltime and moveout-parameters domain and then use similarity-weightedk-means clustering to find the maximum likelihood anisotropy parameters of the main subsurface *** order to demonstrate that,we apply the similarity-weighted clustering method to synthetic and field data examples and the results are of higher accuracy when compared to the ones obtained using multiparameter semblance-based *** estimation error section,it can be seen that the estimation error of multiparameter semblance-based method is about 3-5 times that of the proposed method.

关键词： Nonhyperbolic moveout Predictive painting k-means clustering Seismic velocity analysis Vertical transverse isotropy

Effect of quenching condition on micro inhomogeneous structure of Al-Fe-Ce amorphous alloy

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中国有色金属学会会刊：英文版 2000年第3期10卷 414-417页

作者： ZHANG lin(张林) BIAN Xiu fang(边秀房) WU you shi(吴佑实) li Hui(李辉) Shandong Univ Technol Coll Mat Sci & Engn Jinan 250061 Peoples R China

The microstructures of liquid and amorphous Al 90 Fe 5Ce 5 alloys were studied by X ray diffraction (XRD), and the crystalline behavior of the amorphous alloy was also investigated by differential scanning calorimetry (DSC). The distinct pre peaks were found on the structure factors of the liquid and amorphous alloys. The quenching temperature affects the pre peak area, but does not affect its position. The reduction of quenching temperature decreases the crystallization temperature and the activation energy of the Al Fe Ce amorphous alloy. Quenched from 1 050 ℃, a novel structure with a fine dispersion of Al nanophase particles homogeneously distributed in the amorphous matrix was obtained. And the sensitivity of the Al Fe Ce amorphous alloy to the quenching temperature reflects the micro inhomogeneity of the melt.

关键词： Al Fe Ce amorphous alloys micro inhomogeneous structure quenching temperature

5-羟甲基糠醛在CuPd(111)上的加氢反应机理研究

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原子与分子物理学报 2025年第4期42卷 53-57页

作者：张兴云周广丽石云山东临沂大学化学化工学院临沂276000

采用密度泛函理论,利用包含零点能校正的PBE-D3方法研究了5-羟甲基糠醛在双金属催化剂CuPd(111)上表面的加氢还原反应,考虑了两种反应路径,第一种反应路径是侧链上的醛基氧首先发生加氢反应生成F-CHOH中间体,然后F-CHOH中间体继续加氢生... 详细信息

采用密度泛函理论,利用包含零点能校正的PBE-D3方法研究了5-羟甲基糠醛在双金属催化剂CuPd(111)上表面的加氢还原反应,考虑了两种反应路径,第一种反应路径是侧链上的醛基氧首先发生加氢反应生成F-CHOH中间体,然后F-CHOH中间体继续加氢生成2,5-二羟甲基呋喃;第二种反应路径是侧链上的醛基碳先加氢原还原生成F-CH_(2)O中间体,生成的F-CH_(2)O进一步加氢还原生成2,5-二羟甲基呋喃.计算了两种竞争反应路径的活化能垒和反应热,结果表明,5-羟甲基糠醛在CuPd(111)面加氢还原生成2,5-二羟甲基呋喃的最佳反应路径为:F-CHO→F-CHOH→F-CH_(2)OH.

关键词： 5-羟甲基糠醛活化能垒反应热

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