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Perfect Pick系统订单拣选策略优化研究
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作者 马云峰 邓力 余佳祥 《物流科技》 2024年第22期1-7,共7页
作为电商仓库作业中耗时最长、成本最高的环节,订单拣选的作业效率一直是仓库管理中的关键问题。文章针对拣选策略选择问题,选择Perfect Pick系统的电商仓库作为背景,对单个拣选台进行研究,提出订单分批和订单排序两种拣选策略并进行对... 作为电商仓库作业中耗时最长、成本最高的环节,订单拣选的作业效率一直是仓库管理中的关键问题。文章针对拣选策略选择问题,选择Perfect Pick系统的电商仓库作为背景,对单个拣选台进行研究,提出订单分批和订单排序两种拣选策略并进行对比分析;以货箱搬运次数最少为目标,分别构建订单分批与订单排序两种拣选策略的整数规划模型,并设计贪婪算法进行求解。通过数值实验验证,订单排序策略在所有订单规模中均优于订单分批策略,根据仓库的订单规模,合理设置拣选台最大容量并选择合理的拣选策略,能够更好地提高拣选效率、优化仓库作业环节。 展开更多
关键词 Perfect pick系统 订单拣选 订单分批 订单排序
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A regression approach for seismic first-break picking
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作者 Huan Yuan San-Yi Yuan +2 位作者 Jie Wu Wen-Jing Sang Yu-He Zhao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1584-1596,共13页
The picking efficiency of seismic first breaks(FBs)has been greatly accelerated by deep learning(DL)technology.However,the picking accuracy and efficiency of DL methods still face huge challenges in low signal-to-nois... The picking efficiency of seismic first breaks(FBs)has been greatly accelerated by deep learning(DL)technology.However,the picking accuracy and efficiency of DL methods still face huge challenges in low signal-to-noise ratio(SNR)situations.To address this issue,we propose a regression approach to pick FBs based on bidirectional long short-term memory(Bi LSTM)neural network by learning the implicit Eikonal equation of 3D inhomogeneous media with rugged topography in the target region.We employ a regressive model that represents the relationships among the elevation of shots,offset and the elevation of receivers with their seismic traveltime to predict the unknown FBs,from common-shot gathers with sparsely distributed traces.Different from image segmentation methods which automatically extract image features and classify FBs from seismic data,the proposed method can learn the inner relationship between field geometry and FBs.In addition,the predicted results by the regressive model are continuous values of FBs rather than the discrete ones of the binary distribution.The picking results of synthetic data shows that the proposed method has low dependence on label data,and can obtain reliable and similar predicted results using two types of label data with large differences.The picking results of9380 shots for 3D seismic data generated by vibroseis indicate that the proposed method can still accurately predict FBs in low SNR data.The subsequent stacked profiles further illustrate the reliability and effectiveness of the proposed method.The results of model data and field seismic data demonstrate that the proposed regression method is a robust first-break picker with high potential for field application. 展开更多
关键词 First-break picking Low signal-to-noiseratio Regression BiLSTM TRAVELTIME Geometry Noisy seismic data
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Automatic velocity picking based on optimal key points tracking algorithm
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作者 Yong-Hao Wang Wen-Kai Lu +3 位作者 Song-Bai Jin Yang Li Yu-Xuan Li Xiao-Feng Gu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期903-917,共15页
Picking velocities from semblances manually is laborious and necessitates experience. Although various methods for automatic velocity picking have been developed, there remains a challenge in efficiently incorporating... Picking velocities from semblances manually is laborious and necessitates experience. Although various methods for automatic velocity picking have been developed, there remains a challenge in efficiently incorporating information from nearby gathers to ensure picked velocity aligns with seismic horizons while also improving picking accuracy. The conventional method of velocity picking from a semblance volume is computationally demanding, highlighting a need for a more efficient strategy. In this study, we introduce a novel method for automatic velocity picking based on multi-object tracking. This dynamic tracking process across different semblance panels can integrate information from nearby gathers effectively while maintaining computational efficiency. First, we employ accelerated density clustering on the velocity spectrum to discern cluster centers without the requirement for prior knowledge regarding the number of clusters. These cluster centers embody the maximum likelihood velocities of the main subsurface structures. Second, our proposed method tracks key points within the semblance volume. Kalman filter is adopted to adjust the tracking process, followed by interpolation on these tracked points to construct the final velocity model. Our synthetic data example demonstrates that our proposed algorithm can effectively rectify the picking errors of the clustering algorithm. We further compare the performances of the clustering method(CM), the proposed tracking method(TM), and the variational method(VM) on a field dataset from the Gulf of Mexico. The results attest that our method offers superior accuracy than CM, achieves comparable accuracy with VM, and benefits from a reduced computational cost. 展开更多
关键词 Velocity picking Multi-object tracking Density clustering Kalman filter
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First-Arrival Picking Method for Active Source Data with Ocean Bottom Seismometers Based on Spatial Waveform Variation Characteristics
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作者 LIU Hongwei XING Lei +3 位作者 ZHU Henghua ZHANG Jin ZHANG Jing LIU Huaishan 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期970-980,共11页
The precision and reliability of first-arrival picking are crucial for determining the accuracy of geological structure inversion using active source ocean bottom seismometer(OBS)refraction data.Traditional methods fo... The precision and reliability of first-arrival picking are crucial for determining the accuracy of geological structure inversion using active source ocean bottom seismometer(OBS)refraction data.Traditional methods for first-arrival picking based on sample points are characterized by theoretical errors,especially in low-sampling-frequency OBS data because the travel time of seismic waves is not an integer multiple of the sampling interval.In this paper,a first-arrival picking method that utilizes the spatial waveform variation characteristics of active source OBS data is presented.First,the distribution law of theoretical error is examined;adjacent traces exhibit variation characteristics in their waveforms.Second,a label cross-correlation superposition method for extracting highfrequency signals is presented to enhance the first-arrival picking precision.Results from synthetic and field data verify that the proposed approach is robust,successfully overcomes the limitations of low sampling frequency,and achieves precise outcomes that are comparable with those of high-sampling-frequency data. 展开更多
关键词 first-arrival picking spatial waveform variation label cross-correlation superposition method
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Niemann-Pick C1蛋白在埃博拉病毒感染中的作用及其靶向药物研究进展 被引量:1
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作者 吴海燕 陈国江 《中国药理学与毒理学杂志》 CAS 北大核心 2024年第2期153-160,共8页
埃博拉病毒属丝状病毒科,具有高传染性,能引起人类和灵长类动物出现严重出血热等症状,病死率高达90%。Niemann-Pick C1(NPC1)蛋白是埃博拉病毒感染过程中表达于宿主细胞内体膜上的一个重要受体,其与埃博拉病毒被组织蛋白酶裂解的糖蛋白(... 埃博拉病毒属丝状病毒科,具有高传染性,能引起人类和灵长类动物出现严重出血热等症状,病死率高达90%。Niemann-Pick C1(NPC1)蛋白是埃博拉病毒感染过程中表达于宿主细胞内体膜上的一个重要受体,其与埃博拉病毒被组织蛋白酶裂解的糖蛋白(GP)的相互作用是病毒感染宿主的关键环节,介导病毒囊膜与内体膜的融合,进而将病毒基因组释放到宿主细胞。近年来,将NPC1蛋白作为广谱抗丝状病毒药物靶点研发的小分子抑制剂、单克隆抗体和基因治疗药物均有突破性进展。本文介绍了NPC1的结构及其在埃博拉病毒感染中的作用,并对靶向NPC1的小分子抑制剂、单克隆抗体药物和基因治疗药物的研究现状进行总结。 展开更多
关键词 埃博拉病毒 Niemann-pick C1蛋白 小分子抑制剂 抗体 基因治疗
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Manual Order Picking Route Optimization in Distribution Warehouse of Chain Furniture Retail Enterprise
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作者 Yongzhen Zeng Junkun Wang +1 位作者 Ching-Kuei Kao King-Zoo Tang 《American Journal of Operations Research》 2024年第3期105-136,共32页
Due to the effects of the COVID-19 pandemic and the rise of online shopping, the offline sales of IKEA Fuzhou have been declining since 2020. Because the cost of distribution warehouse is a major expense for offline c... Due to the effects of the COVID-19 pandemic and the rise of online shopping, the offline sales of IKEA Fuzhou have been declining since 2020. Because the cost of distribution warehouse is a major expense for offline chain furniture retailers, and the picking process is a key activity in distribution warehouse operations. To reduce the cost of distribution warehouse and alleviate the survival pressure of the offline chain furniture retailers, this paper focuses on optimizing the picking route of the IKEA Fuzhou distribution warehouse. It starts by creating a two-dimensional coordinate system for the storage location of the distribution warehouse using the traditional S-type picking strategy to calculate the distance and time of the sorting route. Then, the problem of optimizing the picking route is then transformed into the travelling salesman problem (TSP), and picking route optimization model is developed using a genetic algorithm to analyze the sorting efficiency and picking route optimization. Results show that the order-picking route using the genetic algorithm strategy is significantly better than the traditional S-type picking strategy, which can improve overall sorting efficiency and operations, reduce costs, and increase efficiency. Thus, this establishes an implementation process for the order-picking path based on genetic algorithm optimization to improve overall sorting efficiency and operations, reduce costs, increase efficiency, and alleviate the survival pressure of pandemic-affected enterprises. 展开更多
关键词 S-Shaped picking Strategy picking Route Traveling Salesman Problem Genetic Algorithm
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Basic Research on the Burden of Dropping off and Picking up Children: Differences by Employment Type and Gender in the Tokyo Metropolitan Area
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作者 Jun Morio Koshi Isono +1 位作者 Masahiko Kikuchi Tetsuo Morita 《Journal of Transportation Technologies》 2024年第3期445-461,共17页
There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences i... There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences in child drop-off and pick-up by employment type and gender, utilizing the “Metropolitan Area Person Trip Survey,” which is a statistical data set. The study targeted households in which both spouses were between 30 and 49 years old, had children under the age of 6, and included the following three groups. 1) Dual-income Group 1 (both spouses employed/on contract/temporary);2) Dual-income Group 2 (husband employed/on contract/temporary, wife part-time);3) Full-time housewife group (husband employed, wife unemployed). The analysis revealed that a) wives are almost always responsible for dropping off and picking up their children;b) husbands drop off and pick up their children less frequently in dual-income households;and c) households with children raising within 10 to 30 km of Tokyo Station have longer commuting times and need to reduce the burden of dropping off and picking up their children. 展开更多
关键词 Drop-Off and pick-Up Employment Type GENDER Dual-Income Households Tokyo Metropolitan Area
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USTC-Pickers:a Unified Set of seismic phase pickers Transfer learned for China 被引量:9
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作者 Jun Zhu Zefeng Li Lihua Fang 《Earthquake Science》 2023年第2期95-112,共18页
Current popular deep learning seismic phase pickers like PhaseNet and EQTransformer suffer from performance drop in China.To mitigate this problem,we build a unified set of customized seismic phase pickers for differe... Current popular deep learning seismic phase pickers like PhaseNet and EQTransformer suffer from performance drop in China.To mitigate this problem,we build a unified set of customized seismic phase pickers for different levels of use in China.We first train a base picker with the recently released DiTing dataset using the same U-Net architecture as PhaseNet.This base picker significantly outperforms the original PhaseNet and is generally suitable for entire China.Then,using different subsets of the DiTing data,we fine-tune the base picker to better adapt to different regions.In total,we provide 5 pickers for major tectonic blocks in China,33 pickers for provincial-level administrative regions,and 2 special pickers for the Capital area and the China Seismic Experimental Site.These pickers show improved performance in respective regions which they are customized for.They can be either directly integrated into national or regional seismic network operation or used as base models for further refinement for specific datasets.We anticipate that this picker set will facilitate earthquake monitoring in China. 展开更多
关键词 phase picking transfer learning model customization
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Benchmark on the accuracy and efficiency of several neural network based phase pickers using datasets from China Seismic Network 被引量:4
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作者 Ziye Yu Weitao Wang Yini Chen 《Earthquake Science》 2023年第2期113-131,共19页
Seismic phase pickers based on deep neural networks have been extensively used recently,demonstrating their advantages on both performance and efficiency.However,these pickers are trained with and applied to different... Seismic phase pickers based on deep neural networks have been extensively used recently,demonstrating their advantages on both performance and efficiency.However,these pickers are trained with and applied to different data.A comprehensive benchmark based on a single dataset is therefore lacking.Here,using the recently released DiTing dataset,we analyzed performances of seven phase pickers with different network structures,the efficiencies are also evaluated using both CPU and GPU devices.Evaluations based on F1-scores reveal that the recurrent neural network(RNN)and EQTransformer exhibit the best performance,likely owing to their large receptive fields.Similar performances are observed among PhaseNet(UNet),UNet++,and the lightweight phase picking network(LPPN).However,the LPPN models are the most efficient.The RNN and EQTransformer have similar speeds,which are slower than those of the LPPN and PhaseNet.UNet++requires the most computational effort among the pickers.As all of the pickers perform well after being trained with a large-scale dataset,users may choose the one suitable for their applications.For beginners,we provide a tutorial on training and validating the pickers using the DiTing dataset.We also provide two sets of models trained using datasets with both 50 Hz and 100 Hz sampling rates for direct application by end-users.All of our models are open-source and publicly accessible. 展开更多
关键词 neural network deep learning seismic phase picking earthquake detection open-source science
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Pick-up strategies for and electrical characterization of ZnO nanowires with a SEM-based nanomanipulator 被引量:1
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作者 Mei Liu Lingdi Kong +5 位作者 Weilin Su Aristide Djoulde Kai Cheng Jinbo Chen Jinjun Rao Zhiming Wang 《Nanotechnology and Precision Engineering》 CAS CSCD 2023年第1期26-31,共6页
Because of their unique mechanical and electrical properties,zinc oxide(ZnO)nanowires are used widely in microscopic and nanoscopic devices and structures,but characterizing them remains challenging.In this paper,two ... Because of their unique mechanical and electrical properties,zinc oxide(ZnO)nanowires are used widely in microscopic and nanoscopic devices and structures,but characterizing them remains challenging.In this paper,two pick-up strategies are proposed for characterizing the electrical properties of ZnO nanowires using SEM equipped with a nanomanipulator.To pick up nanowires efficiently,direct sampling is compared with electrification fusing,and experiments show that direct sampling is more stable while electrification fusing is more efficient.ZnO nanowires have cut-off properties,and good Schottky contact with the tungsten probes was established.In piezoelectric experiments,the maximum piezoelectric voltage generated by an individual ZnO nanowire was 0.07 V,and its impedance decreased with increasing input signal frequency until it became stable.This work offers a technical reference for the pick-up and construction of nanomaterials and nanogeneration technology. 展开更多
关键词 ZnO nanowires nanomanipulator picking up strategy piezoelectric properties electrical characterization
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MMP15、PICK1基因在山羊睾丸中的表达研究
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作者 汪艳妃 张艳 +1 位作者 惠茂茂 陈祥 《山地农业生物学报》 2023年第4期18-25,共8页
MMP15、PICK1基因均是哺乳动物性腺组织中影响性腺生理功能正常发挥的重要影响因子,但它们在黔北麻羊睾丸组织中的表达规律尚不明晰。为研究黔北麻羊不同月龄的睾丸中MMP15、PICK1基因的表达情况,本试验以黔北麻羊为研究对象,通过qRT-PC... MMP15、PICK1基因均是哺乳动物性腺组织中影响性腺生理功能正常发挥的重要影响因子,但它们在黔北麻羊睾丸组织中的表达规律尚不明晰。为研究黔北麻羊不同月龄的睾丸中MMP15、PICK1基因的表达情况,本试验以黔北麻羊为研究对象,通过qRT-PCR技术分别检测MMP15与PICK1基因在1、3、6、9、12月龄的黔北麻羊睾丸中的表达水平并建立基因表达的标准曲线。结果显示:MMP15、PICK1基因在黔北麻羊不同月龄睾丸组织中均有表达;MMP15基因在黔北麻羊不同月龄睾丸中的表达量从高到低排列为:12月龄>1月龄>9月龄>3月龄>6月龄;12月龄与1月龄的表达差异不显著(P>0.05),二者表达量均极显著高于3月龄、6月龄、9月龄(P<0.01);9月龄表达显著高于3月龄(P<0.05),极显著高于6月龄(P<0.01);3月龄表达极显著高于6月龄(P<0.01)。PICK1基因在黔北麻羊不同月龄睾丸中的表达量从高到低排列分别是:3月龄>6月龄>12月龄>9月龄>1月龄;3、6月龄其表达量极显著高于9、12月龄(P<0.01);1月龄与其他几个月龄相比,其表达量均极显著低于其他月龄(P<0.01)。结合黔北麻羊的生理机能发育情况,黔北麻羊在6月龄时已经基本达到性成熟,所以此时睾丸内细胞活动增强,睾丸机能活跃。本次试验结果表明,黔北麻羊睾丸生精功能的正常发挥或与MMP15及PICK1基因的表达量有关。 展开更多
关键词 黔北麻羊 MMP15 pick1 相对表达量 睾丸
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Truncating PICK1 Variant Identified in Azoospermia Affected Mitochondrial Dysfunction in Knockout Mice
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作者 Yao-qiang DU Chong-yi SHU +11 位作者 Min ZHENG Wei-de XU Yue SUN Lu SHEN Chen ZHANG Yu-xin ZHANG Qian-ni WANG Kai-qiang LI Bing-yu CHEN Ke HAO Jian-xin LYU Zhen WANG 《Current Medical Science》 SCIE CAS 2023年第2期313-323,共11页
Objective The protein interacting with C kinase 1(PICK1)plays a critical role in vesicle trafficking,and its deficiency in sperm cells results in abnormal vesicle trafficking from Golgi to acrosome,which eventually di... Objective The protein interacting with C kinase 1(PICK1)plays a critical role in vesicle trafficking,and its deficiency in sperm cells results in abnormal vesicle trafficking from Golgi to acrosome,which eventually disrupts acrosome formation and leads to male infertility.Methods An azoospermia sample was filtered,and the laboratory detection and clinical phenotype indicated typical azoospermia in the patient.We sequenced all of the exons in the PICK1 gene and found that there was a novel homozygous variant in the PICK1 gene,c.364delA(p.Lys122SerfsX8),and this protein structure truncating variant seriously affected the biological function.Then we constructed a PICK1 knockout mouse model using clustered regularly interspaced short palindromic repeat cutting technology(CRISPRc).Results The sperm from PICK1 knockout mice showed acrosome and nucleus abnormalities,as well as dysfunctional mitochondrial sheath formation.Both the total sperm and motility sperm counts were decreased in the PICK1 knockout mice compared to wild-type mice.Moreover,the mitochondrial dysfunction was verified in the mice.These defects in the male PICK1 knockout mice may have eventually led to complete infertility.Conclusion The c.364delA novel variant in the PICK1 gene associated with clinical infertility,and pathogenic variants in the PICK1 may cause azoospermia or asthenospermia by impairing mitochondrial function in both mice and humans. 展开更多
关键词 pick1 AZOOSPERMIA truncating variant knockout mice mitochondrial dysfunction
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Niemann-Pick A/B Disease in a 13-Year-Old Child and Review of the Literature
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作者 Issam Taha Ilham Tadmori Moustapha Hida 《Open Journal of Pediatrics》 2023年第6期907-913,共7页
Niemann-Pick disease (NPD) refers to a group of patients who have varying degrees of lipid storage and foam cell infiltration in tissues, as well as overlapping clinical features, including hepatosplenomegaly, insuffi... Niemann-Pick disease (NPD) refers to a group of patients who have varying degrees of lipid storage and foam cell infiltration in tissues, as well as overlapping clinical features, including hepatosplenomegaly, insufficiency pulmonary and/or central nervous system (CNS). Thanks to the pioneering work of Roscoe Brady and colleagues, we now know that there are two distinct metabolic abnormalities that explain NPD. The first is due to the deficient activity of the acid sphingomyelinase enzyme (ASM;NPD “types A and B”), and the second is due to defective functioning in the transport of cholesterol (NPD “type C”). We report the case of a 13-year-old adolescent diagnosed with Niemann-Pick A/B disease. 展开更多
关键词 Nieman pick SPLENOMEGALY HEPATOMEGALY Enzymatic Test
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旋转剪切式青花椒采摘装置设计与试验 被引量:1
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作者 杨玲 张原 +5 位作者 何志远 李守太 蒲应俊 陈维汉 杨仕 杨明金 《农业工程学报》 EI CAS CSCD 北大核心 2024年第3期72-83,共12页
针对基于“下桩”采摘方法的青花椒采摘设备存在喂入困难、易堵塞而造成采摘效率低的问题,该研究设计了一种旋转剪切式青花椒采摘装置。首先基于花椒枝物理、力学特性确定旋转剪切式青花椒采摘过程包括花椒枝旋转驱动、花椒枝导向喂入... 针对基于“下桩”采摘方法的青花椒采摘设备存在喂入困难、易堵塞而造成采摘效率低的问题,该研究设计了一种旋转剪切式青花椒采摘装置。首先基于花椒枝物理、力学特性确定旋转剪切式青花椒采摘过程包括花椒枝旋转驱动、花椒枝导向喂入和剪切采摘,剪切采摘功能由往复式切割器实现。并设计双动刀往复式切割器及其传动机构,确定了剪切采摘装置的结构和运动参数。进一步地,运用ANSYS/LS-DYNA构建花椒枝剪切仿真模型,确定最优齿形参数为:刀齿切割角20°,刀齿刃角50°,刀齿厚度2.5 mm,该条件下峰值切割力为3.739 N。最后通过单因素试验确定了花椒枝喂入角度、花椒枝喂入速度、花椒枝旋转速度的取值范围分别为40°~60°、20~40 mm/s、20~40 r/min;并采用BoxBehnken设计法制定三因素二次回归正交组合试验方案,运用Design-Expert 12对试验结果进行方差分析和响应面分析,得到旋转剪切式青花椒采摘装置的最优工作参数为:花椒枝喂入角度55°,花椒枝喂入速度33.21 mm/s,花椒枝旋转速度30 r/min;通过试验验证得出在最优工作参数下,单人单枝喂入时青花椒平均采摘效率为10.95 kg/h,平均采净率为95.57%,平均伤果率为12.87%。研究结果可为青花椒采摘机的研发提供技术参考。 展开更多
关键词 农业机械 优化 有限元分析 青花椒采摘 下桩采摘法 剪切采摘装置
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PICK1参与调控芬太尼诱导的大鼠痛觉过敏机制的研究
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作者 金宇 《生物化工》 CAS 2023年第6期6-9,39,共5页
目的:探讨与蛋白激酶C相互作用的蛋白质1(PICK1)参与调控阿片类药物诱导的痛觉过敏(OIH)的分子机制。方法:颈部皮下注射枸橼酸芬太尼建立大鼠OIH模型,通过PCR实验检测Pick1在大鼠背根神经节(DRG)中表达水平;构建Pick1的过表达载体,包装p... 目的:探讨与蛋白激酶C相互作用的蛋白质1(PICK1)参与调控阿片类药物诱导的痛觉过敏(OIH)的分子机制。方法:颈部皮下注射枸橼酸芬太尼建立大鼠OIH模型,通过PCR实验检测Pick1在大鼠背根神经节(DRG)中表达水平;构建Pick1的过表达载体,包装pLV-Pick1重组慢病毒后对大鼠进行鞘内注射,电生理测定大鼠DRG神经元兴奋性变化,观察慢病毒注射前(T0)、慢病毒表达后(T1)和芬太尼给药后(T2)大鼠机械痛阈。结果:与Control组相比,OIH组大鼠的机械痛阈明显降低;Pick1在OIH大鼠DRG中表达量有明显下调;芬太尼孵育后DRG细胞的动作电位的阈电流明显降低,鞘内注射pLV-Pick1慢病毒的大鼠DRG细胞在芬太尼孵育后,阈电流相无显著下调。结论:在DRG水平上,Pick1可参与调控痛觉过敏,在DRG上干涉Pick1的表达,可以缓解芬太尼诱导的痛觉过敏。 展开更多
关键词 背根神经节 pick1 痛觉过敏 芬太尼
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丘陵果园自然环境下柑橘采摘机器人设计与试验 被引量:6
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作者 鲍秀兰 马志涛 +3 位作者 马萧杰 黎亦书 任梦涛 李善军 《农业机械学报》 EI CAS CSCD 北大核心 2024年第4期124-135,共12页
智慧果园是未来果园行业发展的趋势,智能化果实采摘是发展智慧果园的关键问题。为实现智能化果实采摘,本文搭建了一种适用于丘陵果园矮化栽培模式下的柑橘采摘机器人系统。针对丘陵果园垄间地面凹凸不平,存在地形倾斜角0°~20°... 智慧果园是未来果园行业发展的趋势,智能化果实采摘是发展智慧果园的关键问题。为实现智能化果实采摘,本文搭建了一种适用于丘陵果园矮化栽培模式下的柑橘采摘机器人系统。针对丘陵果园垄间地面凹凸不平,存在地形倾斜角0°~20°,设计了一种自适应调平平台保持机械臂基座水平;通过视觉系统获取多幅点云图像建立果树的三维点云模型,获取果实位置信息;为避免采摘时造成果实损伤,结合柑橘类水果的采摘特点,设计了一种剪切夹持一体化的末端执行器完成柑橘采摘。针对果园自然环境的主要扰动因素(风和光照)进行分级,设置10组对比试验,结果表明:在低光照或正常光照条件下,平均果实定位准确率为82.5%,末端执行器夹取成功率为87.5%,平均采摘时间最短为12.3 s/个;高光照条件下平均果实定位准确率为72%,末端执行器夹取成功率为80%,平均采摘时间最短为12.5 s/个。 展开更多
关键词 柑橘 采摘机器人 三维点云模型 自适应平台 末端执行器
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基于计算机视觉的采摘机器人作业优化研究 被引量:1
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作者 王新科 李凯 《农机化研究》 北大核心 2024年第8期235-239,共5页
为进一步提高我国采摘机器人智能化作业水平及采摘效率,基于计算机视觉应用技术展开优化研究。以采摘机器人结构组成为设计基点,运用视觉控制核心理念建立采摘机器人视觉识别处理与控制数学模型,实施相适应的采摘路径规划和系统采摘状... 为进一步提高我国采摘机器人智能化作业水平及采摘效率,基于计算机视觉应用技术展开优化研究。以采摘机器人结构组成为设计基点,运用视觉控制核心理念建立采摘机器人视觉识别处理与控制数学模型,实施相适应的采摘路径规划和系统采摘状态输出设计。同时,进行视觉采摘验证试验,结果表明:基于计算机视觉的采摘机器人系统优化正确可行,整机综合采摘效率可达94.61%,系统识别准确率与控制精度分别相对提升了6.12%和5.25%,机器人采摘成功率可提升至95.98%。因此,将计算机视觉处理技术有效应用至采摘机器人设计改进,对于类似农业采摘与收获装备开发研究可提供创新及借鉴思路,推广价值良好。 展开更多
关键词 采摘机器人 计算机视觉 视觉控制 识别准确率 采摘成功率
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基于碰撞特性的鲜食玉米摘穗装置对比试验 被引量:1
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作者 张红梅 陈博 +3 位作者 胡经营 李志杰 何勋 王万章 《河南农业大学学报》 CAS CSCD 北大核心 2024年第1期87-95,共9页
【目的】探究缓冲弹簧和柔性触穗表面两种摘穗机构在摘取果穗中的低损作用及机制。【方法】以传统玉米收获用板式摘穗机构和具有缓冲弹簧加柔性触穗表面的柔性摘穗机构为2种摘穗结构,以刚性触穗表面、柔性橡胶触穗表面、柔性发泡材料触... 【目的】探究缓冲弹簧和柔性触穗表面两种摘穗机构在摘取果穗中的低损作用及机制。【方法】以传统玉米收获用板式摘穗机构和具有缓冲弹簧加柔性触穗表面的柔性摘穗机构为2种摘穗结构,以刚性触穗表面、柔性橡胶触穗表面、柔性发泡材料触穗表面为3种触穗表面,得出6种摘穗机构,进行鲜食玉米果穗碰撞试验,采集和分析碰撞时间、碰撞加速度峰值,计算碰撞冲量,统计籽粒破碎率。【结果】柔性摘穗机构能够有效降低鲜食玉米果穗受到的碰撞时间,从而降低鲜食玉米果穗的籽粒破碎率。缓冲弹簧可缩短鲜食玉米果穗的碰撞时间,当柔性摘穗机构表面为柔性橡胶和柔性发泡材料时,碰撞时间分别比板式摘穗机构降低了66.2%、70.1%和70.1%。碰撞冲量分别降低了67.6%、77.9%和79.7%。籽粒破碎率降低了71.2%、51.3%和83.6%。对于柔性摘穗机构,鲜食玉米果穗与柔性橡胶、柔性发泡材料触穗表面的碰撞时间比刚性触穗表面分别延长了58.7%和63.2%。碰撞加速度峰值分别降低了62.5%和68.7%。碰撞冲量分别降低了42.4%和54.5%。籽粒破碎率分别降低了47.4%和68.4%。【结论】通过降低收获过程中鲜食玉米果穗受到的碰撞时间和碰撞加速度,从而有效降低了鲜食玉米果穗的籽粒破碎率,为鲜食玉米低损收获机的研制提供理论依据和设计参考。 展开更多
关键词 鲜食玉米 柔性摘穗 低损 碰撞试验
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分体刀具式名优茶采摘末端执行器设计与试验优化 被引量:3
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作者 陈建能 李杭 +3 位作者 刘林敏 贾江鸣 赵润茂 武传宇 《农业机械学报》 EI CAS CSCD 北大核心 2024年第1期39-46,195,共9页
针对名优茶机械化采摘过程中侧芽无法采摘的问题,根据顶芽、侧芽及茶梗的相关参数并结合茶园环境设计了一种末端执行器,利用分体式刀具的刀齿弯曲变形适应茶梗的干扰从而采摘侧芽。通过有限元仿真刀具切割侧芽得到采摘成功率的影响因素... 针对名优茶机械化采摘过程中侧芽无法采摘的问题,根据顶芽、侧芽及茶梗的相关参数并结合茶园环境设计了一种末端执行器,利用分体式刀具的刀齿弯曲变形适应茶梗的干扰从而采摘侧芽。通过有限元仿真刀具切割侧芽得到采摘成功率的影响因素为刀齿宽度、刀齿长度及刀具厚度;采用三因素三水平的中心组合设计与响应面分析法研究各因素对采摘成功率的交互影响;以采摘成功率为响应值建立二次回归模型,确定各因素对采摘成功率的影响显著性主次排序为:刀齿长度、刀齿宽度、刀具厚度。以采摘成功率为目标对各试验因素进行优化,得到优化后的刀齿宽度、刀具厚度、刀齿长度分别为2.6、0.9、20.0 mm。采用优化后的参数进行茶园采摘试验,结果表明,末端执行器能够有效完成茶叶采摘工作,顶芽、侧芽采摘成功率分别为93%、63%,试验值与预测值的相对误差小于5%,优化模型结果可靠。 展开更多
关键词 名优茶 采茶机器人 末端执行器 分体式刀具 侧芽
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采摘机器人机械手避障方法研究——基于遗传优化和模糊PID控制器 被引量:4
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作者 王娜 孟庆辉 魏宏飞 《农机化研究》 北大核心 2024年第4期203-206,共4页
为了提高采摘机器人机械手移动的自动化程度,使其在移动过程中有效避开障碍物,将基于PID控制器的避障系统引入到了机械手的设计上,并采用遗传算法和模糊算法对控制器进行了优化,提高了机械手移动的准确性和平稳性。模拟采摘机器人机械... 为了提高采摘机器人机械手移动的自动化程度,使其在移动过程中有效避开障碍物,将基于PID控制器的避障系统引入到了机械手的设计上,并采用遗传算法和模糊算法对控制器进行了优化,提高了机械手移动的准确性和平稳性。模拟采摘机器人机械手的作业环境,对机械手的避障功能进行了测试,结果表明:机械手可以成功躲避障碍物,且采用遗传和模糊算法优化的机械手具有更高的移动平稳性,对于提高果实采摘效率和质量具有重要的作用。 展开更多
关键词 采摘机械手 避障系统 遗传算法 模糊算法 PID控制器
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