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Optimization design of fertilizer apparatus owned arc gears based on discrete element method

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International Journal of Agricultural and Biological Engineering 2021年第2期14卷 97-105页

作者： Guoqiang Dun Zhiyong Gao yuxuan liu Wenyi Ji Ning Mao Xingpeng Wu Wenhui liu College of Mechanical and Electrical Engineering Northeast Forestry UniversityHarbin 150040China College of Engineering and Technology Northeast Forestry UniversityHarbin 150040China College of Engineering Northeast Agricultural UniversityHarbin 150030China

To improve the uniformity of the flow when fertilizer apparatus discharges fertilizer,a kind of fertilizer apparatus owned arc gears was designed.Also,the design and working principle of its general structure and key components were analyzed theoretically.Aiming at exploring the influence of arc structural parameters to the performance of arc gears discharging fertilizer,DEM simulation was used in this study.Fertilizer apparatus owned arc gears was taken as the research object to analyze the influence of two key components including the arc radius of gears’concave-grooves and the minimal length between two mutual meshing gears.The variation coefficient of fertilizer discharging amount stability and the linear determined coefficient of fertilizer discharging amount in unit time as evaluation index were selected.Two factors and five levels quadratic rotation orthogonal experiment was applied,and Design-Expert 8.0 software was used to achieve data processing and analysis.The results of experiment indicated that the arc radius of gears’concave-grooves had significant effect on the linear determined coefficient of fertilizer discharging amount in unit time,and the minimal length between two mutual meshing gears had significant effect on the variation coefficient of fertilizer discharging amount stability.The optimum structural parameters were 8.54 mm as the arc radius of gears’concave-grooves and 5.22 mm as the minimal length between two mutual meshing gears.Upon this circumstance,the variation coefficient was 0.28 and determination coefficient was 0.9972.The optimum apparatus was selected to conduct the bench test and field simulation test.The results indicated that the variation coefficient is 0.27,and the linear determined coefficient of is 0.9980.The results of simulation experiment were anastomotic basically with the real result,which showed that DEM simulation technology was usable to the experiment of testing fertilizer discharging.The results of this research can provide a reference to the improving of perform

关键词： agricultural machinery fertilizer apparatus discrete element method experiment structure parameter fertilizing performance

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水蒸气对碘化铅薄膜作用的实验研究

化学工程 2024年第3期52卷 78-83页

作者：刘宇轩高文财许雄文肖圣宗华南理工大学电力学院广东广州510640 广州理工学院建筑工程学院广东广州510540 广东省能源高效清洁利用重点实验室广东广州510640

PSC(钙钛矿太阳能电池)被认为是具有潜力的第三代光伏电池,并具备取代硅电池的可能。然而,钙钛矿薄膜制备时难以控制的结晶过程阻碍着它的大规模生产和商业化进程。因此,提出两步法分步沉积碘化铅和甲基碘化铵薄膜,该方法的成膜质量很... 详细信息

PSC(钙钛矿太阳能电池)被认为是具有潜力的第三代光伏电池,并具备取代硅电池的可能。然而,钙钛矿薄膜制备时难以控制的结晶过程阻碍着它的大规模生产和商业化进程。因此,提出两步法分步沉积碘化铅和甲基碘化铵薄膜,该方法的成膜质量很大程度上取决于第一步沉积的碘化铅层薄膜形貌。为了研究高质量的碘化铅薄膜制备方法,观察高湿度环境下碘化铅薄膜的形貌变化,对比实验前后的碘化铅薄膜的晶体质量,发现水蒸气对碘化铅薄膜形貌具有调控作用。实验结果表明,水蒸气与碘化铅晶体之间存在某种化学作用,从而导致碘化铅的重结晶。在高湿度环境下,合适的作用时间可以改善碘化铅薄膜,为提升钙钛矿薄膜的质量提供思路。

关键词：纳米材料太阳能化学分析碘化铅水蒸气

基于多源数据视角下的厦门山海健康步道活力提升策略研究

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福建建筑 2024年第4期 14-20页

作者：宋雨璇刘静厦门理工学院福建厦门361024

以厦门山海健康步道为对象,对步道空间中服务设施、微博点评数据以及现场踏勘全景照片数据进行总结探索。通过微博点评数据、语义分析等技术手段,对步道内相关10类服务系统数据进行绩效评价。从人的行为活动出发,在步道中拍摄游客视角... 详细信息

以厦门山海健康步道为对象,对步道空间中服务设施、微博点评数据以及现场踏勘全景照片数据进行总结探索。通过微博点评数据、语义分析等技术手段,对步道内相关10类服务系统数据进行绩效评价。从人的行为活动出发,在步道中拍摄游客视角的全景照片,运用FCN软件对其进行客观要素的识别,从而对步道中客观指标测度及量化分析,探寻厦门山海步道空间活力特征及其与环境的内在机制,同时分析总结现有问题,为提高山海步道人群满意度与提升步道使用效能,提出相应的解决策略。

关键词：多源数据厦门山海健康步道活力提升策略

内在情感对癌症发生风险的影响:基于孟德尔随机化研究

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西安交通大学学报（医学版） 2024年第3期45卷 376-382页

作者：杜钦朱雨萱郭一泽许楠馨刘棣西安交通大学第二附属医院肿瘤科陕西西安710004

目的探究内在情感(幸福感、抑郁情绪、忧虑和内疚感)与癌症(结直肠癌、肝癌、甲状腺癌、肺癌、乳腺癌)的因果关系。方法采用两样本双向孟德尔随机化方法。所有数据基于全基因关联研究(GWAS)汇总数据。逆方差加权法(IVW)得到的结果作为... 详细信息

目的探究内在情感(幸福感、抑郁情绪、忧虑和内疚感)与癌症(结直肠癌、肝癌、甲状腺癌、肺癌、乳腺癌)的因果关系。方法采用两样本双向孟德尔随机化方法。所有数据基于全基因关联研究(GWAS)汇总数据。逆方差加权法(IVW)得到的结果作为主要结局指标,加权中值法(WM)、MR-Egger法作为补充结果,评价指标为比值比(OR),并进行敏感性分析。结果对于抑郁情绪,提示与肺癌(OR=1.005,95%CI:1.001~1.009,P=0.015)显著相关。对于忧虑,提示与乳腺癌(OR=1.199,95%CI:1.011~1.423,P=0.038)显著相关。对于内疚感,提示与甲状腺癌(OR=2.083,95%CI:1.080~4.017,P=0.029)显著相关。在去除MR-PRESSO检测到的所有潜在多效性SNPs后,忧虑与乳腺癌的关联无统计学差异(P=0.064),忧虑与结直肠癌显著相关(OR=0.739,95%CI:0.571~0.956,P=0.021)。癌症与内在情感之间的关联未发现存在因果关系。结论抑郁情绪与肺癌发生风险增加相关,内疚感与甲状腺癌发生风险增加相关,忧虑可能与结直肠癌发生风险降低相关。

关键词：两样本双向孟德尔随机化内在情感癌症全基因组关联研究因果效应

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Twin recrystallization mechanisms in a high strain rate compressed Mg-Zn alloy

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Journal of Magnesium and Alloys 2021年第2期9卷 499-504页

作者： yuxuan liu Yangxin Li Qingchun Zhu Huan Zhang Xixi Qi Jinhui Wang Peipeng Jin Xiaoqin Zeng National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite Shanghai Jiao Tong University200240 ShanghaiPR China Qinghai Provincial Engineering Research Center for High Performance Light Metal Alloys and Forming Qinghai UniversityXining 810016PR China

Static recrystallization of a high strain rate compressed Mg-1 Zn(wt.%)alloy was investigated using electron backscattered diffraction(EBSD).A novel 53°1010 structure was observed in the as-deformed alloy,which showed a{1012}-{1012}double twin relationship with the matrix.When the as-deformed alloy was annealed at 200°C,the{1011}compression twins and{1011}-{1012}double twins showed a higher priority to recrystallize.In addition,the coarse{1012}tension twins and their inner double twins were preferentially to recrystallize,while the lenticular tension twins had little impact on the recrystallization.Therefore,obtaining more compression twins or coarse twins instead of lenticular tension twins can be an effective approach to manipulate recrystallization process in deformed Mg alloys.

关键词： Magnesium alloy High strain rate deformation Recrystallization Twin

Shadow–highlight feature matching automatic small crater recognition using high-resolution digital orthophoto map from Chang’E Missions

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Acta Geochimica 2019年第4期38卷 541-554页

作者： Wei Zuo Chunlai Li Lingjie Yu Zhoubin Zhang Rongwu Wang Xingguo Zeng yuxuan liu Yaying Xiong Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China School of Textile Science and Engineering Xi'an Polytechnic UniversityXi'an 710048China College of Textiles Donghua UniversityShanghai 200051China

This paper introduces a new method of small lunar craters’ automatic identification, using digital orthophoto map(DOM) data. The core of the approach is the fact that the lunar exploration DOM data reveal contrasting highlight and shadow characteristics of small craters under sunlight irradiation. This research effort combines image processing and mathematical modeling. Overall it proposes a new planetary data processing approach, to segment and extract the highlight and shadow regions of small craters,using the image gray frequency(IGF) statistical method.IGF can also be applied to identify the coupling relationships between small craters’ shape and their relative features. This paper presents the highlight and shadow pair matching(HSPM) model which manages to perform highprecision automatic recognition of small lunar craters.Testing was performed using the DOM data of Chang’E-2(CE-2). The results have shown that the proposed method has a high level of successful detection rate. The proposed methodology that uses DOM data can complement the drawbacks of the digital elevation model(DEM) that has a relatively high false detection rate. A hybrid fusion model(FUM) that combines both DOM and DEM data, was carried out to simultaneously identify small, medium, and large-sized craters. It has been proven that the FUM generally shows stronger recognition ability compared to previous approaches and it can be adapted for high precision identification of craters on the whole lunar surface.The results meet the requirements for a reliable and accurate exploration of the Moon and the planets.

关键词： Moon Crater recognition Image processing Space exploration

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血液肿瘤患者经济毒性的研究进展

医学与哲学 2024年第5期45卷 74-77页

作者：杨慧武夫梅尹钰煊刘伟山东中医药大学附属医院血液科山东济南250014 济南市章丘区中医医院护理部山东济南250200 山东中医药大学护理学院山东济南250355

针对血液肿瘤患者经济毒性的概念、现状、影响因素(社会人口学、疾病与治疗和医疗保险等方面)、对健康结局的影响以及管理策略五个方面进行综述。对血液肿瘤患者经济毒性的相关信息进行总结,归纳经济毒性对血液肿瘤患者健康相关行为及... 详细信息

针对血液肿瘤患者经济毒性的概念、现状、影响因素(社会人口学、疾病与治疗和医疗保险等方面)、对健康结局的影响以及管理策略五个方面进行综述。对血液肿瘤患者经济毒性的相关信息进行总结,归纳经济毒性对血液肿瘤患者健康相关行为及治疗依从性的影响,提出应对血液肿瘤患者经济毒性的管理策略,采用多方联合,运用财务导航计划,全面评估患者经济毒性水平,为临床治疗决策提供依据。同时,为进一步干预研究提供依据,降低患者经济毒性水平,提高患者生活质量。

关键词：血液肿瘤经济毒性不良健康结局管理策略

计及精细化氢能利用的综合能源系统多时间尺度鲁棒优化策略

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电工技术学报 2024年第5期39卷 1419-1435页

作者：胡俊杰童宇轩刘雪涛王剑晓徐衍会新能源电力系统国家重点实验室(华北电力大学) 北京102206 大数据分析与应用技术国家工程实验室(北京大学) 北京100871

能源结构改革背景下,构建以氢能驱动、电-热为主体的综合能源系统(HEH-IES)具有重要意义。为提高含电氢耦合单元的IES运行灵活性,同时减小功率波动对系统的影响,提出含多元储能与综合需求响应的氢能精细化利用两阶段调度方法。首先,分... 详细信息

能源结构改革背景下,构建以氢能驱动、电-热为主体的综合能源系统(HEH-IES)具有重要意义。为提高含电氢耦合单元的IES运行灵活性,同时减小功率波动对系统的影响,提出含多元储能与综合需求响应的氢能精细化利用两阶段调度方法。首先,分析电制氢(P2H)两阶段运行过程与电氢耦合单元运行特性,对氢能的用能过程与设备进行精细化建模;其次,计及多元储能与综合需求响应提出了日前-日内两阶段多时间尺度优化策略,日前阶段充分考虑能源系统的不确定性,构建数据驱动的分布鲁棒优化(DRO)模型,日内阶段遵从日前计划,考虑多能流在灵活性调节时间尺度上的差异,通过多时间尺度的滚动优化降低功率波动的影响;最后,仿真算例证明了所提模型与策略对提升IES的运行灵活性具有积极作用。

关键词：综合能源系统氢能变载启停特性分布鲁棒优化灵活性多时间尺度

The effect of basal dislocation on {11■1} twin boundary evolution in a Mg-Gd-Y-Zr alloy

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Journal of Materials Science & Technology 2021年第22期81卷 212-218页

作者： Huan Zhang Yangxin Li yuxuan liu Qingchun Zhu Xixi Qi Gaoming Zhu Jinhui Wang Peipeng Jin Xiaoqin Zeng National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite Shanghai Jiao Tong UniversityShanghai200240PR China Qinghai Provincial Engineering Research Center for High Performance Light Metal Alloys and Forming Qinghai UniversityXining810016PR China

This study aims to understand the features of{11■1}twin boundaries in a high strain rate compressed Mg-10 Gd-3Y-0.4Zr using electron backscatter diffraction(EBSD)and transmission electron microscopy(TEM).Based on the Schmid factor calculations,the basal dislocations are easily activated within the{11■1}twin and suppressed in the surrounding matrix.The consequent basal dislocation-twin interaction during deformation can lead to the misorentiation deviation of{11■1}twin boundaries,accompanying with the formation of a step at the twin boundary.Such a{11■1}twin boundary evolution mechanism provides a new vision of twinning behavior in Mg alloys.

关键词： Mg alloys Plastic deformation Twinning Dislocation Misorientation