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Design and experimental study of the end-effector for broccoli harvesting

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 137-144页

作者： xiong zhao Gangji Xu Pengfei Zhang Gaohong Yu Yadan Xu Faculty of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Key Laboratory of Transplanting Equipment and Technology of Zhejiang Province Hangzhou 310018China Hangzhou vocational&Technical College Hangzhou 310018China

The end-effector is an important part of the broccoli harvesting *** at the physical characteristics of a large broccoli head and thick stem,a spherical cutting tool broccoli harvesting end-effector was designed in this ***,the physical characteristics of broccoli were tested,and physical parameters such as the broccoli head diameter and stem diameter of broccoli were *** maximum cutting force of broccoli stems under different cutting angles was ***,according to the physical characteristics and harvesting process of broccoli,the end-effector was designed,and the mathematical model of kinematics and dynamics was *** on the results of dynamic analysis,the end-effector rod was optimized,and the unilateral width of the slider was 40 mm,the length of the connecting rod was 120 mm,and the length of the crank was 42 *** mechanism needed an external driving force of 140.54 N to cut the broccoli ***,a 32 mm cylinder with a load rate of 50%was selected as the power ***,the feasibility of the broccoli harvesting end-effector was verified by the harvesting *** showed that the overall harvesting success rate of the end-effector is 93.3%,and the smoothness rate of the stem section is 83.3%.The harvesting performance of the broccoli end-effector was *** lays a foundation for agricultural robots to harvest broccoli.

关键词： harvesting robot broccoli end-effector dynamic analysis mechanism optimization

Optimization design and experiment of the variable differential gear train planting mechanism

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INTERNATIONAL JOURNAL OF AGRICULTURAL AND BIOLOGICAL ENGINEERING 2024年第2期17卷 85-93页

作者： zhao, xiong Liu, Ziwei Jia, Yuanwu Ma, Xingxiao Zhang, Pengfei Chen, Jianneng Zhejiang Sci Tech Univ Sch Mech Engn Hangzhou 310018 Peoples R China Zhejiang Sci Tech Univ Fac Mech Engn & Automat Hangzhou 310018 Peoples R China Xi An Int Univ Engn Coll Xian 710077 Peoples R China Hangzhou Vocat & Tech Coll Hangzhou 310018 Peoples R China

In order to improve the adaptability of the planting mechanism for different plant spacings, a variable differential gear train planting mechanism based on precise pose and trajectory control was proposed by combining the open chain 2R rod group and the variable differential gear train. According to the pose requirements of receiving seedling point, transporting seedling point and planting point, three precise pose points of constrained planting trajectory were determined. Through the three-position motion generation structural synthesis method, combined with computer-aided optimization design software, a set of mechanism parameters that meet the planting requirements were optimized. Based on the optimized mechanism parameters, by only changing the coordinates of two trajectory shape control points, three planting trajectories with key point position information adapted to 300 mm, 400 mm and 500 mm plant spacing were obtained by interpolation, and three pairs of total transmission ratio of three groups of variable differential gear trains were calculated. When distributing the total transmission ratio of the mechanism, the fixed axis gear train and the differential gear train are combined. The fixed axis gear train included a pair of non-circular gear pairs and a pair of positive gear pairs, which were convenient for disassembly and assembly. The former drives the sun gear at variable speed, and the latter drives the planet carrier at uniform speed. Based on this structure, the transmission ratio of the positive gear pair is -1, and the transmission ratio of the differential gear train is 0.5. The sub-transmission ratio of the single-stage non-circular gear pair was calculated and the pitch curves of three pairs of noncircular gears were solved. Three pairs of non-circular gear pairs with different transmission ratios were replaced in turn and three sets of planting mechanisms were modeled in three dimensions. The virtual prototype motion simulation was completed by

关键词： plant spacing planting mechanism variable differential gear train precise pose trajectory control parameter optimization SEEDLING TRANSPLANTING MECHANISM

Design and experimental research on the sweet potato seedling transplanting mechanism of the planetary gear train with deformed elliptical gear transmission

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INTERNATIONAL JOURNAL OF AGRICULTURAL AND BIOLOGICAL ENGINEERING 2024年第3期17卷 91-99页

作者： Ye, Bingliang Ye, Yuxuan Zhou, Haili Yu, Gaohong zhao, xiong Deng, Bin Zhejiang Sci Tech Univ Fac Mech Engn Hangzhou 310018 Peoples R China Zhejiang Prov Key Lab Transplanting Equipment & Te Hangzhou 310018 Peoples R China Minist Agr & Rural Affairs Coconstruct Minist & Prov Key Lab Agr Equipment Hilly & Mountainous Areas So Hangzhou 310018 Peoples R China

Aiming at the lack of suitable machines for sweet potato seedling transplanting in China, and according to the agronomic requirements for the horizontal insertion method of sweet potato seedling, a new sweet potato seedling transplanting mechanism of planetary gear train was proposed based on the non-uniform transmission of deformed elliptical gear. The working principle of the transplanting mechanism was analyzed, and the kinematics modeling and analysis of the mechanism were carried out. The study established the numerical objectives of the transplanting mechanism and applied the theory of membership function to establish a mathematical model for the parameter-guided optimization design of the transplanting mechanism. The parameter-guided optimization design software was developed to obtain a set of optimal mechanism parameters that satisfied the motion trajectory of sweet potato transplanting and the posture of the transplanting arm. Based on the optimized parameters, the structure of the transplanting mechanism was designed, and a virtual prototype of the mechanism was created, whereby a virtual motion simulation of the transplanting mechanism was conducted to verify the correctness of the kinematics model and design of the mechanism. The high-speed photographic kinematics test of the mechanism prototype and sweet potato seedling transplanting tests were conducted to test the mechanism's kinematic characteristics and transplanting performance. The test results show that the test trajectory of the mechanism and test posture of the transplanting arm are almost consistent with the theoretical and simulation trajectory, meeting the agronomic requirements of the horizontal insertion method of sweet potato seedling; And when the rotary speed of the mechanism are 20 r/min and 30 r/min, the average success ratios of sweet potato seedlings transplanting are 90% and 82%, respectively, which prove the application feasibility of the mechanism in the practical machines.

关键词： sweet potato seedling transplanter transplanting mechanism deformed elliptical gear transmission kinematics analysis membership function optimization design PICK-UP MECHANISM OPTIMIZED DESIGN TESTS

Clinical outcome and prognostic factors of T4N0M0 colon cancer after R0 resection:A retrospective study

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1869-1877页

作者： Bang Liu zhao-xiong Zhang Xin-Yang Nie Wei-Lin Sun Yong-Jia Yan Wei-Hua Fu Department of General Surgery Tianjin Medical University General HospitalTianjin Medical UniversityTianjin 300052China

BACKGROUND Paradoxically,patients with T4N0M0(stage II,no lymph node metastasis)colon cancer have a worse prognosis than those with T2N1-2M0(stage III).However,no previous report has addressed this *** To screen prognostic risk factors for T4N0M0 colon cancer and construct a prognostic nomogram model for these *** Two hundred patients with T4N0M0 colon cancer were treated at Tianjin Medical University General Hospital between January 2017 and December 2021,of which 112 patients were assigned to the training cohort,and the remaining 88 patients were assigned to the validation *** between the training and validation groups were *** training cohort was subjected to multi-variate analysis to select prognostic risk factors for T4N0M0 colon cancer,followed by the construction of a nomogram *** The 3-year overall survival(OS)rates were 86.2%and 74.4%for the training and validation cohorts,***(P=0.000),T stage(P=0.001),right hemicolon(P=0.025),irregular review(P=0.040),and carbohydrate antigen 199(CA199)(P=0.011)were independent risk factors of OS in patients with T4N0M0 colon cancer.A nomogram model with good concordance and accuracy was *** Enterostomy,T stage,right hemicolon,irregular review,and CA199 were independent risk factors for OS in patients with T4N0M0 colon *** nomogram model exhibited good agreement and accuracy.

关键词： T4N0M0 colon cancer Prognosis Multivariate analysis Nomogram Colon cancer

Heavy ion energy influence on multiple-cell upsets in small sensitive volumes:from standard to high energies

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Nuclear Science and Techniques 2024年第5期35卷 109-121页

作者： Yang Jiao Li-Hua Mo Jin-Hu Yang Yu-Zhu Liu Ya-Nan Yin Liang Wang Qi-Yu Chen Xiao-Yu Yan Shi-Wei zhao Bo Li You-Mei Sun Pei-xiong zhao Jie Liu Institute of Modern Physics Chinese Academy of ScienceLanzhou 730000China University of Chinese Academy of Science Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China China Electronics Technology Group Corporation No.58 Research Institute Wuxi 214000China Beijing Microelectronics Technology Institute Beijing 100084China Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China Key Laboratory of Science and Technology on Silicon Devices Chinese Academy of SciencesBeijing 100029China

The 28 nm process has a high cost-performance ratio and has gradually become the standard for the field of radiation-hardened ***,owing to the minimum physical gate length of only 35 nm,the physical area of a standard 6T SRAM unit is approximately 0.16μm^(2),resulting in a significant enhancement of multi-cell charge-sharing ***-cell upsets(MCUs)have become the primary physical mechanism behind single-event upsets(SEUs)in advanced nanometer node *** range of ionization track effects increases with higher ion energies,and spacecraft in orbit primarily experience SEUs caused by high-energy ***,ground accelerator experiments have mainly obtained low-energy ion irradiation ***,the impact of ion energy on the SEU cross section,charge collection mechanisms,and MCU patterns and quantities in advanced nanometer devices remains *** this study,based on the experimental platform of the Heavy Ion Research Facility in Lanzhou,low-and high-energy heavy-ion beams were used to study the SEUs of 28 nm SRAM *** influence of ion energy on the charge collection processes of small-sensitive-volume devices,MCU patterns,and upset cross sections was obtained,and the applicable range of the inverse cosine law was *** findings of this study are an important guide for the accurate evaluation of SEUs in advanced nanometer devices and for the development of radiation-hardening techniques.

关键词： 28 nm static random access memory(SRAM) Energy effects Heavy ion Multiple-cell upset(MCU) Charge collection Inverse cosine law

弹性支承块轨道结构病害对钢轨竖向位移影响研究

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城市轨道交通研究 2024年第S1期27卷 37-41页

作者：赵雄上海地铁维护保障有限公司工务分公司上海200233

[目的]弹性支承块轨道结构因其具有较强的减振降噪特性,在城市轨道交通中被广泛应用。但弹性支承块轨道结构病害对钢轨竖向位移影响较大,需对其进行研究,以有效整治该类病害。[方法]弹性支承块轨道结构主要病害为支承块空吊和扣件失效... 详细信息

[目的]弹性支承块轨道结构因其具有较强的减振降噪特性,在城市轨道交通中被广泛应用。但弹性支承块轨道结构病害对钢轨竖向位移影响较大,需对其进行研究,以有效整治该类病害。[方法]弹性支承块轨道结构主要病害为支承块空吊和扣件失效。基于上海轨道交通8号线弹性支承块轨道结构,建立了弹性支承块轨道静力学模型,分析了无缝线路和有缝线路轨道在列车静荷载下支承块空吊、扣件失效对钢轨竖向位移的影响。[结果及结论]支承块空吊病害会对钢轨竖向位移产生较大影响。对于无缝线路,无支承块空吊病害时的钢轨竖向位移为1.441 mm;对于有缝线路,无支承块空吊病害时的钢轨竖向位移为1.530 mm。发生支承块空吊时,随着支承块空吊量的增加,钢轨竖向最大位移先增加后趋于稳定。在扣件完全失效情况下,钢轨竖向位移会随着失效扣件套数的增加而成倍增加,有缝线路钢轨竖向位移比无缝线路的大0.056~1.186 mm。扣件刚度折减越少,对其他位置钢轨竖向位移影响越小。

关键词：城市轨道交通轨道结构支承块空吊扣件失效钢轨竖向位移

马克思主义理论与中华优秀传统文化内核一致性初探——“第二个结合”的理论意义、内在逻辑与路径探索

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价格理论与实践 2024年第1期 11-16页

作者：李钢熊昭中国社会科学院工业经济研究所/中国社会科学院大学应用经济学院中国社会科学院大学应用经济学院

马克思主义和中华优秀传统文化存在众多相互融通之处:在哲学领域,马克思主义与中华优秀传统文化都将唯物论作为基本内核;农业是工业革命以前最重要的实体经济,中国传统经济思想秉承“重农抑商”观念,认为唯有从事具体的农业、手工业劳... 详细信息

马克思主义和中华优秀传统文化存在众多相互融通之处:在哲学领域,马克思主义与中华优秀传统文化都将唯物论作为基本内核;农业是工业革命以前最重要的实体经济,中国传统经济思想秉承“重农抑商”观念,认为唯有从事具体的农业、手工业劳动才能创造价值,这与马克思主义政治经济学理论基石劳动价值论相一致;科学社会主义和中华优秀传统文化在价值观上异曲同工,都体现了对普通民众的尊重与关照,坚定地站在人民一边。因此,发展马克思主义、推动马克思主义中国化和弘扬中华优秀传统文化可以在新时代中国特色社会主义现代化建设之中得以实现。

关键词：马克思主义中华优秀传统文化第二个结合

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先验中介分析及其应用

系统科学与数学 2024年第7期44卷 2122-2145页

作者：林存洁熊照李扬中国人民大学应用统计科学研究中心&统计学院北京100872

中介分析的主要目的是研究自变量是否通过中介变量来影响因变量.中介分析方法在社会科学和生物医学等领域获得了广泛的研究和应用,已经成为这些领域主流的研究方法.无论是单个中介变量还是多个中介变量的情形,已有许多学者进行了广泛的... 详细信息

中介分析的主要目的是研究自变量是否通过中介变量来影响因变量.中介分析方法在社会科学和生物医学等领域获得了广泛的研究和应用,已经成为这些领域主流的研究方法.无论是单个中介变量还是多个中介变量的情形,已有许多学者进行了广泛的研究,但值得注意的是,这些对中介分析的研究鲜有利用先验信息.在高维的情形下,合理地利用过往研究成果等先验信息,可以有效提升估计和检验的效果.针对这一问题,文章提出了基于先验信息的中介变量选择方法和假设检验方法.理论和数值分析结果表明,文章所提的方法在先验信息质量较好时性能优于现有的方法,在先验信息质量一般时表现出稳健性,性能与现有的方法相差不大.通过对功能基因组学数据集的分析,探索出DNA甲基化在童年创伤和皮质醇应激反应中的中介作用.

关键词：先验信息中介分析变量选择假设检验

鲸鱼算法优化CNN-BiGRU-ATTENTION的车辆换道意图识别模型

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重庆理工大学学报（自然科学） 2024年第6期38卷 73-80页

作者：朱孙科严健容熊开洋熊钊安邦重庆交通大学机电与车辆工程学院重庆400074

针对时空多样特征、超参数敏感性影响车辆行为意图识别精度的问题,提出一种改进的CNN-BiGRU-ATTENTION混合换道意图识别模型。采用目标车辆轨迹序列和与周围车辆互动特征作为模型输入进行训练,实现考虑车辆动态变化状态的意图识别预测;... 详细信息

针对时空多样特征、超参数敏感性影响车辆行为意图识别精度的问题,提出一种改进的CNN-BiGRU-ATTENTION混合换道意图识别模型。采用目标车辆轨迹序列和与周围车辆互动特征作为模型输入进行训练,实现考虑车辆动态变化状态的意图识别预测;使用鲸鱼优化算法对模型调整参数进行多目标寻优,降低模型调优难度;利用NGSIM数据集对模型进行评估校验。结果表明:所提出的WOA-CNN-BiGRU-ATTENTION模型与CNN-BiGRU-ATTENTION模型、Transformer模型相比,准确率分别提升了4.53%、0.97%,达到97.64%;WOA-CNN-BiGRU-ATTENTION模型在不同预判时间下的意图识别准确率最高,在换道前2.5 s的识别精度均能达到91%以上,证明模型具有较强的车辆换道意图识别性能。

关键词：自动驾驶换道意图识别鲸鱼算法双向门控循环单元注意力机制