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基于目标检测和三维重建的弓网燃弧检测方法

城市轨道交通研究 2024年第S1期27卷 1-6,17页

作者：奚笑冬吴丽李世江上海地铁维护保障有限公司上海200235 中国科学院上海微系统与信息技术研究所上海200050

[目的]为提高弓网燃弧检测准确率,针对背景噪声和亮度变化的鲁棒性较弱,以及受到隧道光源、日光、接触线反光及其他异物干扰等问题,提出了一种基于目标检测和三维重建的弓网燃弧检测方法。[方法]首先,采用双目相机的图像获取模块对受电... 详细信息

[目的]为提高弓网燃弧检测准确率,针对背景噪声和亮度变化的鲁棒性较弱,以及受到隧道光源、日光、接触线反光及其他异物干扰等问题,提出了一种基于目标检测和三维重建的弓网燃弧检测方法。[方法]首先,采用双目相机的图像获取模块对受电弓和接触网进行拍摄,获取微秒级实时同步的两幅受电弓与接触网图像;其次,将经过预处理后的图像送入第一检测模块,即进行受电弓与接触网的接触区域以及受电弓与接触网接触点的目标检测;再次,将图像送入燃弧第二检测模块,实现双目图像中的燃弧目标检测;最后,对检测出双目图像中的燃弧进行三维重建,得到燃弧空间三维坐标,用于计算燃弧和受电弓与接触网的接触点的距离,并根据距离滤除错误结果。通过构建YOLOv5-3DR算法模型,对所研制双目立体视觉模块进行试验验证。[结果及结论]所提出的检测方法对复杂应用场景有更好的适应力,能够精准识别燃弧。采用所提出的方法能够极大提高弓网燃弧检测准确率。

关键词：城市轨道交通接触网受电弓燃弧检测目标检测三维重建

基于动态时间弯曲的地铁跨专业数据同步方法研究

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智慧轨道交通 2024年第4期61卷 32-36,41页

作者：李世江上海地铁维护保障有限公司上海200030

跨专业数据融合分析是打破地铁多部门协作数据壁垒、解决多系统联合仿真困难的重要途径,而跨专业数据同步则是数据融合分析的重要保证。为了实现地铁牵引变电站与车辆数据的时间同步,从波形相似性检测的角度提出了一种基于动态时间弯曲... 详细信息

跨专业数据融合分析是打破地铁多部门协作数据壁垒、解决多系统联合仿真困难的重要途径,而跨专业数据同步则是数据融合分析的重要保证。为了实现地铁牵引变电站与车辆数据的时间同步,从波形相似性检测的角度提出了一种基于动态时间弯曲的时间同步方法。通过将牵引变电站的电压波形数据与地铁车辆中的电压波形数据进行匹配分析,实现两者时间同步。结果表明该方法能够计算各个变电站与每一辆列车的时间偏移,具有较高的准确性和有效性,满足工程应用的需求。

关键词：地铁跨专业数据同步波形匹配动态时间弯曲

Can multi-modal neuroimaging evidence from hippocampus provide biomarkers for the progression of amnestic mild cognitive impairment?

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Neuroscience Bulletin 2015年第1期31卷 128-140页

作者： Jiu Chen Zhijun Zhang shijiang li Department of Neurology Affiliated ZhongDa HospitalNeuropsychiatric Institute and Medical School of Southeast University Department of Biophysics Medical College of Wisconsin

Impaired structure and function of the hippocampus is a valuable predictor of progression from amnestic mild cognitive impairment（a MCI） to Alzheimer＇s disease（AD）. As a part of the medial temporal lobe memory system,the hippocampus is one of the brain regions affected earliest by AD neuropathology,and shows progressive degeneration as a MCI progresses to AD. Currently,no validated biomarkers can precisely predict the conversion from a MCI to AD. Therefore,there is a great need of sensitive tools for the early detection of AD progression. In this review,we summarize the specifi c structural and functional changes in the hippocampus from recent a MCI studies using neurophysiological and neuroimaging data. We suggest that a combination of advanced multi-modal neuroimaging measures in discovering biomarkers will provide more precise and sensitive measures of hippocampal changes than using only one of them. These will potentially affect early diagnosis and disease-modifying treatments. We propose a new sequential and progressive framework in which the impairment spreads from the integrity of fibers to volume and then to function in hippocampal subregions. Meanwhile,this is likely to be accompanied by progressive impairment of behavioral and neuropsychological performance in the progression of a MCI to AD.

关键词： Alzheimer's disease amnestic mild cognitive impairment hippocampus episodic memory functional magnetic resonance imaging structural magnetic resonance imaging diffusion tensor imaging multi-modal MRI biomarker

Fast Estimation of Loader’s Shovel Load Volume by 3D Reconstruction of Material Piles

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Chinese Journal of Mechanical Engineering 2023年第5期36卷 187-205页

作者： Binyun Wu Shaojie Wang Haojing lin shijiang li liang Hou Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361102China Shenzhen Research Institute of Xiamen University Shenzhen 518057China

Fast and accurate measurement of the volume of earthmoving materials is of great signifcance for the real-time evaluation of loader operation efciency and the realization of autonomous operation. Existing methods for volume measurement, such as total station-based methods, cannot measure the volume in real time, while the bucket-based method also has the disadvantage of poor universality. In this study, a fast estimation method for a loader’s shovel load volume by 3D reconstruction of material piles is proposed. First, a dense stereo matching method (QORB–MAPM) was proposed by integrating the improved quadtree ORB algorithm (QORB) and the maximum a posteriori probability model (MAPM), which achieves fast matching of feature points and dense 3D reconstruction of material piles. Second, the 3D point cloud model of the material piles before and after shoveling was registered and segmented to obtain the 3D point cloud model of the shoveling area, and the Alpha-shape algorithm of Delaunay triangulation was used to estimate the volume of the 3D point cloud model. Finally, a shovel loading volume measurement experiment was conducted under loose-soil working conditions. The results show that the shovel loading volume estimation method (QORB–MAPM VE) proposed in this study has higher estimation accuracy and less calculation time in volume estimation and bucket fll factor estimation, and it has signifcant theoretical research and engineering application value.

关键词： Loader Volume estimation Binocular stereo vision 3D terrain reconstruction Point cloud registration and segmentation

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跟骨骨折急诊手术与择期手术的临床效果比较

足踝外科电子杂志 2024年第2期11卷 1-5页

作者：李师江李同春吴韦强山东省昌乐县人民医院手足外科山东潍坊262400

目的分析急诊手术与择期手术治疗跟骨骨折的临床效果。方法选取2012年7月至2021年7月于山东省昌乐县人民医院行跟骨骨折手术治疗的69例患者为研究对象,52例患者行急诊手术,17例患者行择期手术。对比急诊手术与择期手术的疗效。结果急诊... 详细信息

目的分析急诊手术与择期手术治疗跟骨骨折的临床效果。方法选取2012年7月至2021年7月于山东省昌乐县人民医院行跟骨骨折手术治疗的69例患者为研究对象,52例患者行急诊手术,17例患者行择期手术。对比急诊手术与择期手术的疗效。结果急诊手术在手术时间、住院天数及住院费用等方面优于择期手术(P0.05)。急诊手术与择期手术术后并发症发生率差异无统计学意义(P>0.05)。术前及术后3个月、6个月、12个月,急诊手术与择期手术视觉模拟评分法(visual analogue scale,VAS)评分及美国足踝外科协会(American Orthopedic Foot and Ankle Society,AOFAS)踝-后足功能评分比较,差异均无统计学意义(P>0.05)。结论伤后6 h内入院的跟骨骨折患者急诊行切开复位内固定术安全有效。

关键词：跟骨骨折急诊跟骨手术择期跟骨手术临床效果

2020年中国1 km格网土地利用程度数据集

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中国科学数据（中英文网络版） 2024年第2期9卷 272-279页

作者：张小桐张定祥汪秀莲彭晋福李亚南李士江中国国土勘测规划院北京100035 自然资源部土地科学数据中心北京100035

土地利用程度综合指数从土地利用方面定量地反映人类活动对生态环境的开发利用程度,是衡量区域土地利用深度和广度的重要指标。2020年中国1 km格网土地利用综合程度数据集是基于2020年度全国国土变更调查数据制作的30米栅格数据,基于土... 详细信息

土地利用程度综合指数从土地利用方面定量地反映人类活动对生态环境的开发利用程度,是衡量区域土地利用深度和广度的重要指标。2020年中国1 km格网土地利用综合程度数据集是基于2020年度全国国土变更调查数据制作的30米栅格数据,基于土地利用程度综合指数模型对全国土地利用程度进行定量评价和分析,将土地利用分为4级:未利用地、林草水用地、农业用地和城镇聚落用地,综合计算区域土地利用受到的人为干预程度;同时为了保证数据正确性和准确性,采用统一规范的数据处理方法、样本采集规则和质量控制体系,对数据成果进行质量控制。本数据集可用于国土空间规划、区域开发与发展评价、主体功能区评价、人地关系耦合分析等研究。

关键词：土地利用程度综合指数国土调查格网分级指数中国

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水稻配方施肥与施用新型肥料成效研究

耕作与栽培 2024年第4期44卷 75-77,80页

作者：周娜王晶琴李世江张文选张明刚绥阳县农业农村局贵州绥阳563300

为探索夏优的水稻大田生产科学施肥方法,采取随机区组试验设计,开展了水稻配方施肥、施用新型肥料(2种)、常规施肥的田间对比试验。研究表明,最佳方法是采用单质氮、磷、钾肥按配方组配施肥,既能增产,同时肥料成本相对较低,经济效益好,... 详细信息

为探索夏优的水稻大田生产科学施肥方法,采取随机区组试验设计,开展了水稻配方施肥、施用新型肥料(2种)、常规施肥的田间对比试验。研究表明,最佳方法是采用单质氮、磷、钾肥按配方组配施肥,既能增产,同时肥料成本相对较低,经济效益好,可采用的配方为10-5-8,其中磷肥普钙一次性施用于底肥;氮肥通常采用尿素,其中20%施于底肥、30%施为第一次追肥、50%施为第二次追肥;钾肥通常采用氯化钾,其中40%作底肥、60%作拔节期追肥;其次,采用新型肥料“鄂中牌长效缓释掺混肥料(24-8-10)”55 kg/667 m~2或“奥牌氯化钾型中氯复混肥料(20-7-8)”66 kg/667 m~2作底肥一次性施用。

关键词：水稻配方施肥新型肥料常规施肥

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The Glutamatergic Postrhinal Cortex–Ventrolateral Orbitofrontal Cortex Pathway Regulates Spatial Memory Retrieval

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Neuroscience Bulletin 2019年第3期35卷 447-460页

作者： Xinyang Qi Zhanhong Jeff Du lin Zhu Xuemei liu Hua Xu Zheng Zhou Cheng Zhong shijiang li liping Wang Zhijun Zhang Department of Neurology Affiliated ZhongDa HospitalInstitute of NeuropsychiatrySchool of MedicineSoutheast UniversityNanjing 210009China Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science Chinese Academy of Sciences (CAS) Center for Excellence in Brain Science and Intelligence Technologythe Brain Cognition and Brain Disease Institute for Collaboration Research of the Shenzhen Institutes of Advanced Technology at the CAS and the McGovern Institute at Massachusetts Institute of TechnologyShenzhen 518055China Department of Biophysics Medical College of WisconsinMilwaukeeWI53226USA

A deficit in spatial memory has been taken as an early predictor of Alzheimer’s disease(AD) or mild cognitive impairment(MCI). The uncinate fasciculus(UF) is a long-range white-matter tract that connects the anterior temporal lobe with the orbitofrontal cortex(OFC)in primates. Previous studies have shown that the UF impairment associated with spatial memory deficits may be an important pathological change in aging and AD, but its exact role in spatial memory is not well understood. The pathway arising from the postrhinal cortex(POR) and projecting to the ventrolateral orbitofrontal cortex(vlOFC)performs most of the functions of the UF in *** the literature suggests an association between spatial memory and the regions connected by the POR–vlOFC pathway, the function of the pathway in spatialmemory is relatively unknown. To further illuminate the function of the UF in spatial memory, we dissected the POR–vlOFC pathway in mice. We determined that the POR–vlOFC pathway is a glutamatergic structure, and that glutamatergic neurons in the POR regulate spatial memory retrieval. We also demonstrated that the POR–vlOFC pathway specifically transmits spatial information to participate in memory retrieval. These findings provide a deeper understanding of UF function and dysfunction related to disorders of memory, as in MCI and AD.

关键词： Spatial memory Postrhinal cortex Ventrolateral orbitofrontal cortex Mild cognitive impairment Alzheimer's disease

Genome wide investigation of Hsf gene family in Phoebe bournei:identification,evolution,and expression after abiotic stresses

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Journal of Forestry Research 2024年第5期35卷 201-215页

作者： Wenhai liao Xinghao Tang Jingshu li Qiumian Zheng Ting Wang Shengze Cheng Shiping Chen shijiang Cao Guangqiu Cao College of Forestry Fujian Agriculture and Forestry UniversityFuzhou 350002People’s Republic of China University Key Laboratory of Forest Stress Physiology Ecology and Molecular Biology of Fujian ProvinceFuzhou 350002People’s Republic of China Fujian Academy of Forestry Sciences Fuzhou 350002People’s Republic of China College of Plant Protection Fujian Agriculture and Forestry UniversityFuzhou 350002People’s Republic of China

Heat shock transcription factors(Hsfs)have important roles during plant growth and development and responses to abiotic *** identification and func-tion of Hsf genes have been thoroughly studied in various herbaceous plant species,but not woody species,especially Phoebe bournei,an endangered,unique species in *** this study,17 members of the Hsf gene family were identi-fied from *** using bioinformatic ***-netic analysis indicated that PbHsf genes were grouped into three subfamilies:A,B,and *** motifs,three-dimensional structure,and physicochemical properties of the PbHsf proteins were also *** structure of the PbHsf genes varied in the number of exons and ***-diction of cis-acting elements in the promoter region indi-cated that PbHsf genes are likely involved in responses to plant hormones and stresses.A collinearity analysis dem-onstrated that expansions of the PbHsf gene family mainly take place via segmental *** expression levels of PbHsf genes varied across different plant *** the basis of the expression profiles of five representative PbHsf genes during heat,cold,salt,and drought stress,PbHsf pro-teins seem to have multiple functions depending on the type of abiotic *** systematic,genome-wide investigation of PbHsf genes in *** and their expression patterns provides valuable insights and information for further func-tional dissection of Hsf proteins in this endangered,unique species.

关键词： Phoebe bournei Hsf gene family Evolutionary analysis Expression mechanism Abiotic stresses