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茄子新品种早红茄2号的选育

中国瓜菜 2024年第9期37卷 179-182页

作者：李倩汪端华吴双花王鑫杨建国湖南省蔬菜研究所长沙410125

早红茄2号是以129D为母本、463D为父本选育而成的早熟紫红色果皮卵圆形茄子新品种。该品种长沙地区春秋播生育期160~180 d左右,植株生长势较强,株型半直立,株高约86 cm,株幅约80 cm;始花节位9~12节,隔2~3节1花;果实卵圆形,紫红色,光泽度... 详细信息

早红茄2号是以129D为母本、463D为父本选育而成的早熟紫红色果皮卵圆形茄子新品种。该品种长沙地区春秋播生育期160~180 d左右,植株生长势较强,株型半直立,株高约86 cm,株幅约80 cm;始花节位9~12节,隔2~3节1花;果实卵圆形,紫红色,光泽度好,果萼少刺;果长12 cm,果粗9 cm,单果质量350 g左右;果肉白色,肉质细嫩、味甜,667 m^(2)产量3500 kg左右;对茄子青枯病、黄萎病和绵疫病有较强的抗性,适合长江中下游地区大棚、露地早熟栽培和夏播秋茄栽培。2020年通过安徽省非主要农作物品种鉴定登记。

关键词：茄子新品种早红茄2号

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基于改进YOLO v8的煤中杂物检测研究

中国煤炭 2024年第4期50卷 115-125页

作者：王克凡王羽玲童建良杨建国国家煤加工与洁净化工程技术研究中心江苏省徐州市221116 中国矿业大学化工学院江苏省徐州市221116

针对选煤厂毛煤中夹杂的铁丝、编织袋、木头、网片等杂物会对智能干选设备运行及后续生产环节造成严重影响的问题,提出一种基于改进YOLO v8的手选胶带杂物识别方法。引入全局注意力机制,增强图像跨维度特征交互;引入加权双向特征金字塔... 详细信息

针对选煤厂毛煤中夹杂的铁丝、编织袋、木头、网片等杂物会对智能干选设备运行及后续生产环节造成严重影响的问题,提出一种基于改进YOLO v8的手选胶带杂物识别方法。引入全局注意力机制,增强图像跨维度特征交互;引入加权双向特征金字塔网络结构,通过自适应控制不同尺度特征图之间的融合,提高模型对杂物的多尺度检测能力。在此基础上,采用WIoU损失函数替换CIoU损失函数,改善模型训练过程中样本质量的平衡问题,以提高模型的性能。通过数据增强扩充煤中杂物数据集,依据实验验证改进YOLO v8的结果。实验结果表明,改进后的算法与原YOLO v8相比,对手选胶带煤中杂物的平均检测精度明显提高,为毛煤入选前的预先智能除杂奠定了基础。

关键词：煤炭除杂目标检测特征融合注意力机制损失函数

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两种直动式高速电磁阀数值模拟与动态响应对比分析

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内燃机工程 2024年第4期45卷 81-88页

作者：范玉陈聿章谢良涛杨建国武汉理工大学船海与能源动力工程学院武汉430063 船舶动力工程技术交通行业重点实验室武汉430063

针对直动式高速电磁阀动铁芯与阀芯加工、装配工艺要求高,一致性较差的问题,提出了一种动铁芯与阀芯可分离的结构,基于AMESim平台建立此款电磁阀电–磁–机–气多物理场耦合模型,考虑了动铁芯与阀芯撞击与分离的情况,并在试验台上进行... 详细信息

针对直动式高速电磁阀动铁芯与阀芯加工、装配工艺要求高,一致性较差的问题,提出了一种动铁芯与阀芯可分离的结构,基于AMESim平台建立此款电磁阀电–磁–机–气多物理场耦合模型,考虑了动铁芯与阀芯撞击与分离的情况,并在试验台上进行了验证。然后与另一种动铁芯与阀芯“绑定”的结构形式进行比较分析。结果表明:两种电磁阀在动态响应与影响动态响应的关键参数存在差别。在同等条件下,第一种结构形式的电磁阀动态响应整体略差,但是其对动铁芯–阀芯加工、装配工艺的要求较低。

关键词：直动式高速电磁阀数值模拟动态响应装配工艺

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弹幕不文明语言分布及对策研究

情报探索 2024年第8期 89-96页

作者：范娟娟杨建国北京华文学院培训部北京102206 北京语言大学首都国际文化研究基地北京100038

[目的/意义]随着弹幕文化的普及和大众化,对弹幕语言尤其是弹幕不文明语言的调查研究更显重要。弹幕不文明语言的相关研究结论,可以帮助加强对弹幕不文明语言行为的监控,更好地服务于网络舆情监测工作。[方法/过程]基于使用频率较高的... 详细信息

[目的/意义]随着弹幕文化的普及和大众化,对弹幕语言尤其是弹幕不文明语言的调查研究更显重要。弹幕不文明语言的相关研究结论,可以帮助加强对弹幕不文明语言行为的监控,更好地服务于网络舆情监测工作。[方法/过程]基于使用频率较高的不文明词语及其分布的1492个弹幕视频的相关变量,通过构建回归模型分析不文明词语分布的影响因素。[结果/结论]官方账号中的不文明词语总体使用和负向使用概率较高,娱乐、科技、知识、国创、生活主题中的不文明词语出现率较高,视频时长、传播参与度、传播深度对不文明词语分布具有显著的影响。

关键词：弹幕不文明语言分布视频发布者视频主题视频热度

Study on the long-distance target apperception techniques for underwater vehicles

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Journal of Systems Engineering and Electronics 2007年第3期18卷 484-490页

作者： yang Xudong Huang jianguo Zhang Qunfei Tang Qi Dept. of Electronics and Communication Engineering Coll. of Marine Engineering Northwestern Polytechnical Univ. Xi'an 710072 P. R. China

The limited physical size for autonomous underwater vehicles （AUV） or unmanned underwater vehicles （UUV） makes it difficult to acquire enough space gain for localizing long-distance targets. A new technique about long-distance target apperception with passive synthetic aperture array for underwater vehicles is presented. First, a synthetic aperture-processing algorithm based on the FFT transform in the beam space （BSSAP） is introduced. Then, the study on the flank array passive long-distance apperception techniques in the frequency scope of 11-18 kHz is implemented from the view of improving array gains, detection probability and augmenting detected range under a certain sea environment. The results show that the BSSAP algorithm can extend the aperture effectively and improve detection probability. Because of the augment of the transmission loss, the detected range has the trend of decline with the increase of frequency under the same target source level. The synthesized array could improve the space gain by nearly 7 dB and SNR is increased by about 5 dB. The detected range is enhanced to nearly 2 km under the condition of 108-118 dB of the target source level for AUV system in measurement interval of nearly 1 s.

关键词： long-distance apperception synthetic aperture processing array gain detection probability detectedrange.

Effect of Welding Technologies on Decreasing Welding Residual Stress of Francis Turbine Runner

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Journal of Materials Science & Technology 2010年第10期26卷 951-956页

作者： Shude Ji Liguo Zhang Xuesong Liu jianguo yang School of Aerospace Engineering Shenyang Aerospace University Shenyang 110034 China State Key laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China

On basis of the subsection welding and the local heating s reasonable technological parameters obtained by plane experiment,the welding residual stress field of some Francis turbine runner is regulated and *** the experimental plane with a thickness of 16 mm,the effect of subsection welding on decreasing welding residual stress of the prior welding section is obvious when the distance is less than 50 mm away from the end of latter welding *** the local heating,the best position,where the effect on decreasing the welding residual stress of plane is best,is 60 mm or so away from the edge of heating *** experimental results of runner show that the subsection welding can make the residual compressive stress engender in the blade dangerous area while the stress value is greatly influenced by the length of the welding section of blade *** local heating can further decrease the value of residual stress near blade outlet,while the local heating processed after heat treatment is better than that processed before heat treatment.

关键词： Blade Subsection welding Local heating Welding residual stress

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TP347H不锈钢焊接接头敏化特性分析

焊接学报 2024年第1期45卷 64-72,I0007页

作者：李乘安冯道臣章霖郑文健程茂鲁显京杨建国浙江工业大学杭州310014 一重集团大连核电石化有限公司大连116113 浙江省特种设备科学研究院杭州310020

为明确TP347H不锈钢焊接接头敏化特性,对焊接接头进行不同条件的敏化处理.结果表明,焊接接头热影响区敏化倾向严重,敏化过程中由于Nb原子在晶界上的结合能高于Cr原子,会先形成了粗大的初级铌碳化合物,后形成细小的二次铌碳化合物.在700... 详细信息

为明确TP347H不锈钢焊接接头敏化特性,对焊接接头进行不同条件的敏化处理.结果表明,焊接接头热影响区敏化倾向严重,敏化过程中由于Nb原子在晶界上的结合能高于Cr原子,会先形成了粗大的初级铌碳化合物,后形成细小的二次铌碳化合物.在700℃下保温时,焊接接头热影响区的敏化度呈现先提高后降低的趋势,当温度达到800℃及以上时,热处理不再提高接头热影响区的敏化度.与实际生产线上服役21000 h的F347H接头热影响区敏化特性对比,证实TP347H焊接接头650℃保温100 h即可达到敏化极限,其原因是Nb元素含量为C元素的数倍,大部分C元素与Nb元素结合形成NbC,而晶粒中扩散的C元素已与Cr元素充分结合,造成的敏化程度达到平衡状态.

关键词： TP347H不锈钢敏化焊接接头热处理耐蚀性

INFLUENCE OF BLADES' STRESS STATE ON FRANCIS TURBINE RUNNER'S INVALIDATION

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Chinese Journal of Mechanical Engineering 2006年第1期19卷 113-115页

作者： JI Shude FANG Hongyuan yang jianguo Astronautical Science and Technology Academy Shenyang Institute ofAeronautical EngineeringShenyang 110034 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001. China

Numerical simulation on Francis turbine runner＇s welding temperature field and welding stress field is carded out on the base of solving the problem of welding heat source＇s movement along any spatial routes and the problem of heat elimination between the complicated blade and air. The evolvement law of welding stress and the distribution of the stress field after welding are obtained. The results indicate that the peak value of the welding residual stress appears on the outlet edge of blade near the contact area between blade and band or blade and crown. Associated with the distribution of the runner＇s working stress, the invalidation reason of the Francis turbine runner is explained.

关键词： Runner Blade Stress field Invalidation

Influence of Ta on Microstructure and Abrasive Wear Resistance of Laser Clad NiCrSiB Coating

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Journal of Wuhan University of Technology(Materials Science) 2013年第3期28卷 437-443页

作者：余廷 DENG Qilin DONG Gang yang jianguo School of Mechanical and Electrical Engineering Nanchang University School of Mechanical Engineering Shanghai Jiaotong University School of Materials Science and Engineering Tongji University

A mixture of NiCrSiB alloy powder and tantalum （Ta） powder was used as laser clad material to improve abrasive wear resistance of the Ni-based coating. The microstructure and wear resistance of the coating were investigated. Addition of Ta element works to suppress the growth of coarse M7C3 carbide in the coating, resulting in a decrease in aspect ratio of coarse carbide. In the abrasive wear test, in situ synthesized TaC particles well bond with Ni-based matrix, and are hardly pull out from wear surface. Grooves on the worn surface of NiCrSiB coating are much deeper and sharper than those in the NiCrSiB＋Ta composite coating. Also, a weight loss of the composite coating is much lower than that of the NiCrSiB coating. The wear resistance of the laser clad Ni-based coating is enhanced to a much greater extent through the addition of Ta. This is attributed to the in situ synthesized hard TaC particles of nearly equiaxed shape, the Ni-based matrix strengthened by Ta and the decrease in aspect ratio of the coarse brittle carbides.

关键词： laser cladding Ni-based alloy wear resistance tantalum TaC particle reinforcement