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An improved method for edge detection based on neighbor distance for processing hemispheric photography

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Journal of Plant Ecology 2024年第2期17卷 134-145页

作者： Yasi Liu dayong Fan han Sun Xiangping Wang State Key Laboratory of Effcient Production of Forest Resources School of Ecology and Nature ConservationBeijing Forestry UniversityBeijing 100083China The Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing 100083China

Hemisphere photos are now widely applied to provide information about solar radiation dynamics,canopy structure and their contribution to biophysical processes,plant productivity and ecosystem *** present study aims to improve the original‘edge detection’method for binary classifcation between sky and canopy,which works not well for closed *** supposed such inaccuracy probably is due to the infuence of sky pixels on their neighbor canopy ***,we introduced a new term‘neighbor distance’,defned as the distance between pixels participated in the calculation of contrast at the edges between classifed canopy and sky,into the‘edge detection’*** showed that choosing a suitable neighbor distance for a photo with a specifc gap fraction can signifcantly improve the accuracy of the original‘edge detection’*** developed an ND-IS(Neighbor Distance-Iteration Selection)method that can automatically determine the threshold values of hemisphere photos with high accuracy and *** combines the modifed‘edge detection’method and an iterative selection method,with the aid of an empirical power function for the relationship between neighbor distance and manually verifed gap *** procedure worked well throughout a broad range of gap fractions(0.019-0.945)with different canopy compositions and structures,in fve forest biomes along a broad gradient of latitude and longitude across Eastern *** results highlight the necessity of integrating neighbor distance into the original‘edge detection’*** advantages and limitations of the method,and the application of the method in the feld were also discussed.

关键词： hemisphere photos ‘edge detection’method neighbor distance gap fraction forest

Effect of Initial Oxide Film on the Formation and Performance of Plasma Electrolytic Oxidation Coating on 7075 Aluminum Alloy

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Acta Metallurgica Sinica(English Letters) 2022年第9期35卷 1559-1571页

作者： Mingyu Zhu Yingwei Song Kaihui Dong dayong Shan En-Hou han Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China

In the early stage of plasma electrolytic oxidation(PEO),the quick formation of the initial oxide film on the surface of the aluminum substrate is necessary for the subsequent discharge spark ***,the compactness of the initial oxide film greatly affects the quality of the PEO coating,but the related mechanisms are not investigated in *** this paper,the status of the initial oxide film was adjusted by adding the(NaPO)into the based electrolyte,and then the effect of initial oxide film on the formation of the PEO coating was *** and chemical composition were analyzed by scanning electron microscope,transmission electron microscopy and X-ray photoelectron *** compactness of the initial oxide film was characterized by Mott-Schottky *** corrosion resistance was measured by electrochemical impedance *** results show that the addition of(NaPO)can promote the co-deposition of phosphide compound into the initial oxide film and improve the film compactness,which is beneficial for the more uniform spark discharge in the later *** a result,the addition of(NaPO)is helpful to obtain PEO coating with better performance.

关键词： Aluminum alloys Plasma electrolytic oxidation Initial oxide film Growth process Spark discharge Compactness

相同提取条件下野生大球盖菇羊肚菌马鞍菌多糖含量的比较研究

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农产品加工 2024年第5期 61-64页

作者：李文文努尔买买提韩大勇石越伊犁师范大学微生物资源保护与开发利用重点实验室新疆伊宁835000 伊犁师范大学生物与地理科学学院新疆伊宁835000

大球盖菇、羊肚菌、马鞍菌均为营养价值极高的野生食用菌,其食用菌多糖具有提高免疫力、降血糖、抗癌等功效,采用索氏提取去除脂肪,三氯乙酸去除蛋白,以蒸馏水作为对照,用苯酚硫酸法进行处理测吸光度,得到在相同条件下提取3种不同的菌... 详细信息

大球盖菇、羊肚菌、马鞍菌均为营养价值极高的野生食用菌,其食用菌多糖具有提高免疫力、降血糖、抗癌等功效,采用索氏提取去除脂肪,三氯乙酸去除蛋白,以蒸馏水作为对照,用苯酚硫酸法进行处理测吸光度,得到在相同条件下提取3种不同的菌种多糖时,大球盖菇的多糖含量最少,羊肚菌的多糖含量最高。

关键词：野生大球盖菇羊肚菌马鞍菌多糖含量测定

瘦素及其受体在真孕和假孕母犬下丘脑-垂体-性腺轴各组织中的表达

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甘肃农业大学学报 2021年第4期56卷 1-7,15页

作者：狄和双王利刚韩大勇蒋珊珊孙庆蘅江苏农牧科技职业学院江苏泰州225300

【目的】研究胚胎着床期瘦素(leptin)及其受体(OB-R)在真孕和假孕母犬下丘脑-垂体-性腺轴各组织中的表达差异.【方法】应用反转录聚合酶链反应(RT-PCR)和免疫组织化学的方法检测胚胎着床期真孕和假孕母犬下丘脑、垂体、卵巢、输卵管、... 详细信息

【目的】研究胚胎着床期瘦素(leptin)及其受体(OB-R)在真孕和假孕母犬下丘脑-垂体-性腺轴各组织中的表达差异.【方法】应用反转录聚合酶链反应(RT-PCR)和免疫组织化学的方法检测胚胎着床期真孕和假孕母犬下丘脑、垂体、卵巢、输卵管、子宫组织中瘦素及其受体的表达.【结果】瘦素在真孕和假孕母犬的下丘脑、垂体、卵巢、子宫中均有表达,在输卵管中表达阴性,瘦素受体在真孕和假孕母犬各组织中均有表达;瘦素及其受体在真孕母犬下丘脑、卵巢和子宫组织中的表达量显著高于假孕母犬(P0.05).【结论】瘦素及其受体对于犬的胚胎着床具有一定调节作用.

关键词：母犬瘦素受体假孕表达

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密级配橡胶沥青路面降噪技术原理与研究综述

长沙理工大学学报（自然科学版） 2024年第3期21卷 61-78,106页

作者：韩大勇王亮郭朋召鲁巍巍杨兴旺中电建路桥集团有限公司北京海淀区100089 长沙理工大学交通运输工程学院湖南长沙410114 河南金欧特实业集团股份有限公司河南许昌461000

密级配橡胶沥青路面是低噪声路面发展的新形式。为了推动低噪声路面的发展,阐述了轮胎/路面噪声的产生、增强机理及密级配橡胶沥青路面的降噪机理和降噪效果。首先介绍大孔隙和密级配两种类型降噪沥青路面及其降噪机理,然后对轮胎/路面... 详细信息

密级配橡胶沥青路面是低噪声路面发展的新形式。为了推动低噪声路面的发展,阐述了轮胎/路面噪声的产生、增强机理及密级配橡胶沥青路面的降噪机理和降噪效果。首先介绍大孔隙和密级配两种类型降噪沥青路面及其降噪机理,然后对轮胎/路面噪声的产生和增强机制进行论述,接着针对密级配降噪沥青路面降噪模式、胎路噪声的影响因素及检测方法进行重点评述,最后对密级配低噪声沥青路面的发展及优化方向进行展望。大多数低噪声沥青路面都偏向于开级配大孔隙类型,对密级配沥青路面的降噪机理及实现路径研究较少。开级配大孔隙沥青路面在孔隙堵塞时,其降噪效果急剧下降,并且堵塞的孔隙难以恢复,这制约了其广泛使用。而密级配橡胶沥青路面通常依靠自身丰富的表面纹理及橡胶颗粒的弹性实现吸声阻尼降噪,故不存在上述不足。密级配橡胶沥青路面虽在降噪效果方面不如开级配大孔隙路面,但因其优异的路用性能和持久稳定的降噪效果,已成为低噪声路面在实际工程应用中的重要选择。为了更好应用密级配橡胶降噪沥青路面,未来应重点研究影响其降噪效果的诸多重要因素,如橡胶颗粒的掺入方式、粒径和掺量等。

关键词：道路工程降噪路面沥青玛蹄脂碎石混合料(SMA) 密级配橡胶沥青路面降噪机理噪声检测

Product/metal ratio (PMR):A novel criterion for the evaluation of electrolytes on micro-arc oxidation (MAO) of Mg and its alloys

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Science China(Technological Sciences) 2011年第10期54卷 2795-2801页

作者： SONG LaiWen SONG YingWei Shan dayong ZHU GuoYi han EnHou State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Product/metal ratio (PMR) was introduced as a novel criterion for the evaluation of electrolytes on micro-arc oxidation (MAO) of Mg and its alloys. The criterion initially sprang from Pilling-Bedworth ratio (PBR), focused on the roles of electrolytes for the compactness of the fabricated coatings, and took attention on properties of reactants/products during MAO. Meanwhile, based on our experiments as well as the results from literatures, the effects of electrolyte additives on morphologies and com-positions of the fabricated MAO coatings of Mg alloys were exploited for verification and supplement of the initial criterion. In combination of the initial PMR criterion and experimental verification, PMR could be represented by special mode (PMRs=Voxide products/Valloy substrates) and general mode (PMRg= PMRs+ PMRd). The ideal PMRs should be between 1 and 2, while PMRd is related to the coating deposition during MAO. PMRd is a supplement to PMRs when the effect of the overlaying prop-erty (O) of the coatings and the effective deposition (D) of electrolyte composites are considered (PMRd=f(O, D). O is related to the melting point (MP) and boiling point (BP) of the MAO products. D is related to the effective reactions between alloy substrates and electrolytes during MAO.

关键词： micro-arc oxidation Mg alloys Pilling-Bedworth ratio product/metal ratio

基于宏基因组测序技术对绵羊呼吸道微生物群落的研究

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中国饲料 2022年第18期 31-34页

作者：刘海霞韩大勇闫伟朱爱文周明夏王步忠吴昊耿昕之江苏农牧科技职业学院江苏泰州225300 江苏西来原生态农业有限公司江苏泰州225328 江苏省阜宁县农业农村局江苏盐城224400

试验采用宏基因组测序技术对4例呼吸道症状发病绵羊(试验组)和4例健康绵羊(对照组)的鼻拭子样本进行高通量测序,分析不同样品间微生物菌群结构功能差异。结果发现,试验组物种注释上,厚壁菌门、变形菌门、拟杆菌门、放线菌门占主导地位;... 详细信息

试验采用宏基因组测序技术对4例呼吸道症状发病绵羊(试验组)和4例健康绵羊(对照组)的鼻拭子样本进行高通量测序,分析不同样品间微生物菌群结构功能差异。结果发现,试验组物种注释上,厚壁菌门、变形菌门、拟杆菌门、放线菌门占主导地位;功能注释上,信号传导、氨基酸代谢所含基因数量最多;抗性基因注释上,葡萄球菌和埃希氏杆菌属耐药基因分布最广存在于8个样品中,耐药基因novA、antibiotic、msbA、Mycobacterium、macB广泛存在于除了样品D1以外的其他样品中。发病绵羊呼吸道微生物菌群结构较为复杂,呼吸道菌群结构变化对绵羊机体发病影响显著。

关键词：绵羊宏基因组病原微生物高通量测序群落结构

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深穿开挖影响的覆土变形规律研究

施工技术 2020年第S01期49卷 102-105页

作者：韩大勇郭忠猛王亚东张硕王玉肖中电建路桥集团有限公司北京100048 北京市市政工程研究院北京100037 北京科技大学北京100083

城市地下工程的大量建设对周边覆土层势的稳定性势必产生不同程度的影响。以高精度探地雷达前期普查和多维度变形测量后期监测为研究手段,对某城市深穿开挖隧道周边覆土进行变形规律研究。雷达前期普查首先确定了2处监测区域中度疏松区... 详细信息

城市地下工程的大量建设对周边覆土层势的稳定性势必产生不同程度的影响。以高精度探地雷达前期普查和多维度变形测量后期监测为研究手段,对某城市深穿开挖隧道周边覆土进行变形规律研究。雷达前期普查首先确定了2处监测区域中度疏松区A和轻微疏松区C;后期监测数据显示,A,C区域x轴向变形规律明显,均面向开挖隧道,为整体变形,变形量随深度的增加而减小。y轴向变形无固定方向,且为分层错动;A区域变形深度范围为地下0~4m,2处各方向变形值最大为0.5mm,在安全范围内证明了支护结构的有效性。

关键词：深穿开挖雷达监测多维度变形监测规律研究

本科层次畜牧兽医专业职教课程体系构建探索与研究

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职业技术 2021年第12期20卷 7-13页

作者：闫伟李巨银刘海霞朱爱文韩大勇江苏农牧科技职业学院动物科技学院江苏泰州225300

本科层次职业教育对加快建设我国现代职业教育体系意义重大,江苏农牧科技职业学院在入选国家"双高计划"高水平学校的基础上申请合并转设为本科层次职业技术大学,积极探索构建本科层次畜牧兽医专业职教课程体系。文章在分析畜牧兽医专业... 详细信息

本科层次职业教育对加快建设我国现代职业教育体系意义重大,江苏农牧科技职业学院在入选国家"双高计划"高水平学校的基础上申请合并转设为本科层次职业技术大学,积极探索构建本科层次畜牧兽医专业职教课程体系。文章在分析畜牧兽医专业岗位发展及专业人才能力需求的基础上,提出构建能力("专业能力+综合能力+智慧信息能力")与特色课程("共享课程、模块课程和畜牧产业课程")匹配的主干课程体系,及"课程思政+创新创业素养"互融的配套课程体系,实现"1+X"证书、职业资格、技能等级培训与课程体系的融通,可以为后续本科层次畜牧兽医专业建设提供参考。

关键词：本科层次职业教育岗位能力课程体系