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老树新花:2026 Moto Guzzi V100 Mandello S
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作者 方云飞 《摩托车》 2026年第1期54-59,共6页
作为拥有百年历史的经典品牌,摩托·古兹拥有与众不同的审美理念和技术特点,其中最具代表性、最有识别度的,就是90°夹角的横置V2发动机,左右缸如同张开双翅的烈火雄鹰,搭载骑手飞向自由空间。站在新百年的起点上,2024年摩托... 作为拥有百年历史的经典品牌,摩托·古兹拥有与众不同的审美理念和技术特点,其中最具代表性、最有识别度的,就是90°夹角的横置V2发动机,左右缸如同张开双翅的烈火雄鹰,搭载骑手飞向自由空间。站在新百年的起点上,2024年摩托·古兹迈出了革命步伐,推出了他们的首台搭载水冷发动机的V100Mandello。但是,这只雄鹰并没有止步于此,又推出了更加先进的V100Mandello S,加持更多的技术能量,让自由之旅澎湃着风火激情! 展开更多
关键词 v100 Mandello s Moto Guzzi
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Evaluation of NLLoc positioning method and seismogenic structure analysis of Luanzhou M_(S)4.3 earthquake
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作者 Zhang Yang Wang Xiao-Shan +3 位作者 Chen Ting Lv Guo-Jun Yu Hai-lin Chen Jun-lin 《Applied Geophysics》 2025年第3期729-738,894,895,共12页
NLLoc is a nonlinear search positioning method.In this study,we use simulated arrival time data to quantitatively evaluate the NLLoc method from three aspects:arrival time picking accuracy,station distribution,and vel... NLLoc is a nonlinear search positioning method.In this study,we use simulated arrival time data to quantitatively evaluate the NLLoc method from three aspects:arrival time picking accuracy,station distribution,and velocity model.The results show that the NLLoc method exhibits high positioning accuracy and stability in terms of arrival time picking accuracy and station distribution;however,it is sensitive to the velocity model.The positioning accuracy is higher when the velocity model is smaller than the true velocity.We combined absolute and relative positioning methods.First,we use the NLLoc method for absolute positioning of seismic data and then the double difference positioning method for relative positioning to obtain a more accurate relocation result.Furthermore,we used the combined method to locate the earthquake sequence after collecting dense seismic array data on the Luanzhou M_(S)4.3 earthquake that occurred on April 16,2021,in Hebei Province.By fitting the fault plane with the relocated earthquake sequences,the results show that the strike and dip angles of the seismogenic fault of the Luanzhou M_(S)4.3 earthquake are 208.5°and 85.6°,respectively.This indicates a high-dip angle fault with North-North-East strike and North-West dip directions.Furthermore,we infer that the seismogenic fault of the Luanzhou M_(S)4.3 earthquake is the Lulong fault. 展开更多
关键词 NLLoc method Combined multiple positioning methods Luanzhou M_(s)4.3 earthquake seismogenic structure Lulong fault
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An Automatic Damage Detection Method Based on Adaptive Theory-Assisted Reinforcement Learning
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作者 Chengwen Zhang Qing Chun Yijie Lin 《Engineering》 2025年第7期188-202,共15页
Current damage detection methods based on model updating and sensitivity Jacobian matrixes show a low convergence ratio and computational efficiency for online calculations.The aim of this paper is to construct a real... Current damage detection methods based on model updating and sensitivity Jacobian matrixes show a low convergence ratio and computational efficiency for online calculations.The aim of this paper is to construct a real-time automated damage detection method by developing a theory-assisted adaptive mutiagent twin delayed deep deterministic(TA2-MATD3)policy gradient algorithm.First,the theoretical framework of reinforcement-learning-driven damage detection is established.To address the disadvantages of traditional mutiagent twin delayed deep deterministic(MATD3)method,the theory-assisted mechanism and the adaptive experience playback mechanism are introduced.Moreover,a historical residential house built in 1889 was taken as an example,using its 12-month structural health monitoring data.TA2-MATD3 was compared with existing damage detection methods in terms of the convergence ratio,online computing efficiency,and damage detection accuracy.The results show that the computational efficiency of TA2-MATD3 is approximately 117–160 times that of the traditional methods.The convergence ratio of damage detection on the training set is approximately 97%,and that on the test set is in the range of 86.2%–91.9%.In addition,the main apparent damages found in the field survey were identified by TA2-MATD3.The results indicate that the proposed method can significantly improve the online computing efficiency and damage detection accuracy.This research can provide novel perspectives for the use of reinforcement learning methods to conduct damage detection in online structural health monitoring. 展开更多
关键词 Reinforcement learning Theory-assisted Damage detection Newton’s method Model updating Architectural heritage
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Study on the Effects of Umbilical Acupuncture’s“Wind-Thunder Interaction Method”on Neuro-Vascular Regulatory Peptide Groups in SCH Patients with Liver Stagnation and Spleen Deficiency
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作者 Yongfeng Li Jialin Cheng +2 位作者 Hairong Wang Bihai Zhou Jianguo Mao 《Journal of Clinical and Nursing Research》 2025年第11期249-255,共7页
Objective:To evaluate the therapeutic efficacy of the umbilical acupuncture’s“Wind-Thunder Interaction Method”in treating schizophrenia(SCH)patients with liver stagnation and spleen deficiency.Methods:A total of 12... Objective:To evaluate the therapeutic efficacy of the umbilical acupuncture’s“Wind-Thunder Interaction Method”in treating schizophrenia(SCH)patients with liver stagnation and spleen deficiency.Methods:A total of 120 SCH patients with liver stagnation and spleen deficiency were selected and evenly divided by ball drawing.The umbilical acupuncture group received the“Wind-Thunder Interaction Method”,while the Western medicine group received pure Western medicine treatment.The outcomes were compared in terms of efficacy and other indicators.Results:The umbilical acupuncture group showed a higher total effective rate,a decrease in disease symptom scores,lower scores on the side effect rating scale,improved cognitive function scores,and excellent laboratory indicators,with p<0.05 between the groups.Conclusion:The“Wind-Thunder Interaction Method”of umbilical acupuncture demonstrated a relatively high effectiveness in treating SCH patients with liver stagnation and spleen deficiency,alleviating symptoms,reducing side effects,improving cognitive function,and facilitating the recovery of neuro-vascular regulatory peptide groups. 展开更多
关键词 Umbilical acupuncture’s“Wind-Thunder interaction method sCH Liver stagnation and spleen deficiency Neuro-vascular regulatory peptide groups
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A Self-Sacrifice Template Method to Produce FeS Encapsulated into N,S Co-Doped Carbon for Improved Lithium Storage Performance
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作者 Xu Liu Lan-Yun Yang +7 位作者 Li-Ting Zeng Yun Peng Chen-Xi Xu Lei Li Jia-Le Sun Yang-Yang Chen Liang Chen Zhao-Hui Hou 《Acta Metallurgica Sinica(English Letters)》 2025年第9期1637-1644,共8页
The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile ... The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile self-sacrifice template method is developed to prepare FeS encapsulated into N,S co-doped carbon(FeS/NSC)composite using melamine-cyanuric acid(MCA)supermolecule as a multifunctional template precursor.The function of MCA supermolecule for material synthesis is explored,revealing its special function as a dispersant,dopant and pore-forming agent.Furthermore,the effect of Fe source dosage on the morphology,structure and composition of the final products is explored.The resultant FeS/NSC-0.1(where 0.1 represents the mass of added Fe source)exhibits the most optimal proportion,characterized by a good dispersion status of FeS within the NSC matrix,effective N,S co-doping and ample porosity.Benefiting from these merits,the FeS/NSC-0.1 anode demonstrates significantly improved cycling stability and rate capability when compared to the counterparts.Undoubtedly,this work offers a universal method to produce advanced transition metal sulfide/carbon composite electrodes for energy storage and conversion systems. 展开更多
关键词 Lithium-ion batteries Lithium storage performance self-sacrifice template method Melamine-cyanuric acid(MCA)supermolecule Fes encapsulated into N s co-doped carbon(Fes/NsC)composite
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基于轻量化YOLO v5s-MCA的番茄成熟度检测方法 被引量:6
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作者 奚小波 丁杰源 +5 位作者 翁小祥 王昱 韩连杰 邹赟涵 唐子昊 张瑞宏 《农业机械学报》 北大核心 2025年第3期383-391,436,共10页
针对自然环境下番茄识别易受复杂背景干扰、相邻果实成熟度相似难以检测等问题,本文提出了一种轻量化YOLO v5s-MCA番茄成熟度识别模型,划分成熟期、转熟期、转色期和未熟期4个成熟度等级。该模型在YOLO v5s基础上使用MobileNetV3网络,... 针对自然环境下番茄识别易受复杂背景干扰、相邻果实成熟度相似难以检测等问题,本文提出了一种轻量化YOLO v5s-MCA番茄成熟度识别模型,划分成熟期、转熟期、转色期和未熟期4个成熟度等级。该模型在YOLO v5s基础上使用MobileNetV3网络,减少了模型参数量;在主干网络和颈部网络引入坐标注意力机制(Coordinate attention,CA),提高了模型对番茄特征表达能力;将颈部网络替换为加权双向特征金字塔网络BiFPN,强化了模型特征融合性能并提高了模型识别准确率;将颈部网络中的标准卷积模块改进为GSConv卷积,减轻了模型复杂度并提高了对目标信息的获取能力。试验结果表明,YOLO v5s-MCA模型参数量仅为2.33×10^(6),计算量仅为4.1×10^(9),模型内存占用量仅为4.83 MB,其精准度和平均精度均值分别达到92.8%和95.1%,相对YOLO v5s基础模型分别提升3.4、4.4个百分点。对比YOLO v3s、YOLO v5s、YOLO v5n、YOLO v7、YOLO v8n及YOLO v10n等6种模型,YOLO v5s-MCA模型轻量化效果与检测性能最优。 展开更多
关键词 番茄 成熟度检测 图像识别 YOLO v5s 轻量化
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Clinical application and research of Shao's “three-acupoint and five-needling method” 被引量:1
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作者 张奥 严兴科 刘安国 《World Journal of Acupuncture-Moxibustion》 CSCD 2017年第1期74-80,共7页
Professor SHAO Jing-ming has obtained more significant effect during the clinical practice in treatment of wheezing diseases by adopting "three-acupoint and five-needling method" created by himself, and the effect h... Professor SHAO Jing-ming has obtained more significant effect during the clinical practice in treatment of wheezing diseases by adopting "three-acupoint and five-needling method" created by himself, and the effect has been widely recognized by doctors and patients. After decades of development, Shao's "three-acupoint and five-needling method" has become a therapy with complete theoretical system and a large number of clinical research achievements, and its application scope has been expanded. In this paper, the achievements of Shao's "three-acupoint and five-needling method" during clinical studies in the early, middle and current development stages and related problems were reviewed comprehensively. 展开更多
关键词 three-acupoint andmethod wheezing diseases clinicain the same wayfive-needling method shao's needlingobservation different diseases be treated
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基于改进YOLO v5s算法的红枣缺陷检测与分拣方法
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作者 史鹏涛 田政伟 +1 位作者 李晓泽 危康乐 《江苏农业科学》 北大核心 2025年第5期83-88,共6页
针对当前生产活动中缺陷红枣的人工识别与分拣劳动强度大、效率低、分拣效果不理想的问题,设计一款基于机器视觉的红枣缺陷检测与分拣设备。首先建立多品种、多照明环境下的红枣缺陷检测样本图库,通过高斯滤波等数据增强技术增强了图像... 针对当前生产活动中缺陷红枣的人工识别与分拣劳动强度大、效率低、分拣效果不理想的问题,设计一款基于机器视觉的红枣缺陷检测与分拣设备。首先建立多品种、多照明环境下的红枣缺陷检测样本图库,通过高斯滤波等数据增强技术增强了图像表面特征,并利用图库分析了红枣缺陷形貌和图像特征。然后针对训练后的YOLO v5s模型检测效果不理想的问题,分别通过引入锚框尺寸优化和添加预测头、引入注意力分配机制和学习率自适应等方法对网络进行了改进与优化,优化后模型训练效果准确率提高7百分点,对红枣缺陷检测的效果有明显增强,与当前热门的检测网络YOLO v3、YOLO v4和YOLO v4-tiny模型对比,YOLO v5s模型平均精度均值分别高7.4、2.3、5.7百分点。试验结果表明,改进后的红枣缺陷检测网络能够有效实现红枣缺陷识别,平均检测准确率达到85.3%,其中黄河滩枣检测准确率可达到87.5%,与分拣设备配合使用能够较好地完成红枣缺陷识别与分拣任务。本研究设计的缺陷检测与分拣平台能够为相关农产品的智能化检测与自动分拣装备的设计与研发提供借鉴和参考。 展开更多
关键词 缺陷检测 机器视觉 自动分拣 YOLO v5s 红枣
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基于改进YOLO v5s的叶菜病虫害检测算法研究
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作者 贺洪江 刘毅祥 王双友 《江苏农业科学》 北大核心 2025年第5期244-250,共7页
叶菜病虫害的早期识别是提高叶菜产量和质量的重要保障,为提高常见叶菜病虫的检测精度,针对实际生产中的复杂环境,以YOLO v5s为基准模型,提出一种改进的FV-YOLO v5s模型。首先,在主干网络中融合CA注意力机制模块与C3特征提取模块,形成了... 叶菜病虫害的早期识别是提高叶菜产量和质量的重要保障,为提高常见叶菜病虫的检测精度,针对实际生产中的复杂环境,以YOLO v5s为基准模型,提出一种改进的FV-YOLO v5s模型。首先,在主干网络中融合CA注意力机制模块与C3特征提取模块,形成了C3CA模块以增强叶菜病虫害的特征提取能力。接着在颈部网络中使用Slim-neck范式设计,高效提取图像中小尺寸目标的特征,增强特征融合的效率。最后用WIoU损失对原损失函数CIoU进行替换,更快地达到收敛状态并提升模型检测性能。结果表明,新模型的精度、召回率和平均精度均值分别达到了92.2%、91.5%、94.8%。改进后的模型FV-YOLO v5s对比原YOLO v5s模型算法,精度、召回率、平均精度均值分别提高2.7、1.4、1.8百分点,优于现有的识别网络,包括YOLO v7、YOLO v8、Faster R-CNN等模型。FV-YOLO v5s模型适用于现代农业生产环境,有助于快速识别和检测叶菜病虫害,且该研究为智慧农业中的叶菜高品质和高产量提供了依据,从而最大限度地减少经济损失。 展开更多
关键词 叶菜病虫害 YOLO v5s CA注意力机制 slim-neck WIoU损失函数
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Comparative Analysis of Improving Effects of 12 Maize Populations with Improved S_1 Selection Method
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作者 孙峰成 冯勇 +6 位作者 付增娟 苏二虎 张来厚 赵瑞霞 刘志雄 石海波 李美娜 《Agricultural Science & Technology》 CAS 2014年第10期1687-1692,1713,共7页
ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of... ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of grains per row and 100-grain weight were the three important component traits of maize yield. The highest genetic increment was found in Mengqun 2, fol owed by Mengqun 4, Mengqun 1 and other 7 maize populations. Negative genetic increment was shown in Mengqun 3 and 3 introduced foreign maize populations. Some changes were shown in spikes, plant traits and genetic diversity of maize populations. Based on our results, we concluded that Mengqun 2, Mengqun 4, Zhongzong 7, Mengqun C and Mengqun A could be directly used for the line breeding by selfing for their higher genetic increment of yield and better improvement effects of other agricultural traits. Compared with these 5 populations, the improvement potential of other maize populations was limited for their lower genetic increment. 展开更多
关键词 lmproved s1 selection method Maize population Genetic gain Comparative analysis
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跨媒介叙事视域下V.S.奈保尔《抵达之谜》中的“如画”书写
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作者 刘须明 《外国语言文学》 2025年第4期74-83,135,共11页
“如画”书写具有明显的跨媒介叙事特征。“如画”书写在文本中创造出栩栩如生的画面来激发读者的想象力,以获得一种特别的审美体验。“如画”强调人的视觉行为,折射人对自然的认识和对如画景观中人的思考。奈保尔的《抵达之谜》以一种... “如画”书写具有明显的跨媒介叙事特征。“如画”书写在文本中创造出栩栩如生的画面来激发读者的想象力,以获得一种特别的审美体验。“如画”强调人的视觉行为,折射人对自然的认识和对如画景观中人的思考。奈保尔的《抵达之谜》以一种近距离的“凝视”方式,对英国南部乡村景观进行如画式书写,用冷静和客观的笔触,揭橥英帝国殖民主义的衰亡本质。如画景观与人物内心的情感互动、与殖民身份以及社会变迁紧密关联,形成了奈保尔式的如画书写特征。 展开更多
关键词 如画书写 跨媒介叙事:v.s.奈保尔 《抵达之谜》
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基于改进YOLOv8s的花色布疵点检测算法 被引量:1
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作者 王跃坤 徐洋 +2 位作者 余智祺 解国升 盛晓伟 《棉纺织技术》 2025年第2期41-48,共8页
针对花色布背景图案复杂、部分疵点目标小、与背景分离难度大,及其带来的自动化实时检测挑战等问题,提出一种基于改进YOLOv8s的花色布疵点检测算法。为增强网络检测疵点小目标的能力,引入BiFPN(Bi⁃directional Feature Pyramid)特征融... 针对花色布背景图案复杂、部分疵点目标小、与背景分离难度大,及其带来的自动化实时检测挑战等问题,提出一种基于改进YOLOv8s的花色布疵点检测算法。为增强网络检测疵点小目标的能力,引入BiFPN(Bi⁃directional Feature Pyramid)特征融合网络,充分融合语义信息和位置信息,增强算法区分疵点和背景的能力;同时,注意到疵点小目标中低质量样本对检测结果的影响,引入WIoU v3损失函数,抑制训练过程中低质量样本产生的有害梯度;最后,引入FasterBlock模型改进原始模型neck中的C2f模块,降低模型整体的参数量。结果表明:改进后的YOLOv8s模型在整个数据集的mAP@0.5∶0.95上可达59.6%,比原YOLOv8s模型提高了2.8个百分点;小目标的APs@0.5∶0.95可达45.1%,比原YOLOv8s模型提高了8.3个百分点;改进后模型参数量为10.557 M,检测速度可达131.6帧/s。认为:改进的YOLOv8s有效提升了沾污、花毛等小目标的检测效果。 展开更多
关键词 花色布 疵点检测 YOLOv8s BiFPN FasterBlock WIoU v3损失函数
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Effect of synthesis methods on activity of V2O5/CeO2/WO3-TiO2 catalyst for selective catalytic reduction of NOx with NH3 被引量:17
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作者 沈美庆 徐丽丽 +4 位作者 王建强 李晨旭 王务林 王军 翟燕萍 《Journal of Rare Earths》 SCIE EI CAS CSCD 2016年第3期259-267,共9页
The effect of synthesis methods on the activity of V/Ce/WTi catalysts was investigated for the selective catalytic reduction(SCR) of NO_x by NH_3. V/Ce/WTi-DP(deposition precipitation) catalyst showed excellent NH... The effect of synthesis methods on the activity of V/Ce/WTi catalysts was investigated for the selective catalytic reduction(SCR) of NO_x by NH_3. V/Ce/WTi-DP(deposition precipitation) catalyst showed excellent NH_3-SCR performance, especially the better medium-temperature activity and the less N_2O formation than V/Ce/WTi-IMP(impregnation). These catalysts were characterized by X-ray diffraction(XRD), Brumauer-Emmett-Teller(BET), X-ray photoelectron spectroscopy(XPS), temperature-programmed reduction(H_2-TPR), and in situ DRIFTS techniques. The XPS and H_2-TPR results revealed that V/Ce/WTi-DP exhibited more surface Ce species, higher level of Oα and higher reducibility of Ce species. Reflected by in situ DRIFTS results, the deposition precipitation method(DP) contributed to a greater amount of weakly adsorbed NO_2, monodentate nitrate and NH_3 species with better reactive activity. Meanwhile, the cis-N_2O_2^(2-) species, an intermediate for N_2O formation, was very limited. As a result, these advantages brought about the superior SCR activity and N_2 selectivity for V/Ce/WTi-DP. 展开更多
关键词 v/WTi Ce-modified synthesis method Ce species NH3-sCR rare earths
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Study on Characteristics of 3-D Translating-Pulsating Source Green Function of Deep-Water Havelock Form and Its Fast Integration Method 被引量:20
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作者 许勇 董文才 《China Ocean Engineering》 SCIE EI 2011年第3期365-380,共16页
The singularities, oscillatory performances and the contributing factors to the 3-'D translating-pulsating source Green function of deep-water Havelock form which consists of a local disturbance part and a far-field ... The singularities, oscillatory performances and the contributing factors to the 3-'D translating-pulsating source Green function of deep-water Havelock form which consists of a local disturbance part and a far-field wave-like part, are analyzed systematically. Relative numerical integral methods about the two parts are presented in this paper. An improved method based on LOBATTO rule is used to eliminate singularities caused respectively by infinite discontinuity and jump discontinuous node from the local disturbance part function, which makes the improvement of calculation efficiency and accuracy possible. And variable substitution is applied to remove the singularity existing at the end of the integral interval of the far-field wave-like part function. Two auxiliary techniques such as valid interval calculation and local refinement of integral steps technique in narrow zones near false singularities are applied so as to avoid unnecessary integration of invalid interval and improve integral accordance. Numerical test results have proved the efficiency and accuracy in these integral methods that thus can be applied to calculate hydrodynamic performance of floating structures moving in waves. 展开更多
关键词 translating-pulsating source Green's function singularity highly oscillatory function integration method
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基于改进YOLO v5s的水下小目标检测算法
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作者 梁衡 刘儒一 +1 位作者 张典 宋廷强 《青岛科技大学学报(自然科学版)》 2025年第2期122-131,共10页
针对目前水下图像存在图像模糊以及小目标聚集导致水下小目标识别精度低的情况,提出一种基于改进YOLO v5s的水下小目标检测算法。在主干特征提取网络中嵌入卷积注意力模块,强化小目标信息,提高网络模型的特征提取能力。设计了一种改进... 针对目前水下图像存在图像模糊以及小目标聚集导致水下小目标识别精度低的情况,提出一种基于改进YOLO v5s的水下小目标检测算法。在主干特征提取网络中嵌入卷积注意力模块,强化小目标信息,提高网络模型的特征提取能力。设计了一种改进的C3模块C3Swin,在原始C3模块中加入Swin Transformer结构,在不同滑动窗口间进行信息交互,增强了全局信息的提取能力。对原始YOLO v5s的检测层进行重构,增加小目标检测层,提升小目标的检测精度。改进损失函数,使用α-iou对原损失函数进行优化,提升预测框的回归精度。实验结果表明,在URPC水下目标检测数据集中,本工作提出的算法平均精度均值(mAP)为86.9%,相较于原模型提升了2.9%,检测速度为62.7 Hz,优于主流算法,在保证检测速度的同时提升了检测精度。 展开更多
关键词 水下小目标检测 YOLO v5s 卷积注意力模块 swin Transformer α-iou
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基于改进轻量化YOLOv5s的万寿菊识别方法
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作者 李欣 徐博 +3 位作者 张雷 于浩 贾英新 刘子剑 《计算机测量与控制》 2025年第6期185-192,199,共9页
针对传统识别网络结构冗余且普适性低,导致推理过程复杂、效能低下,难以满足密集生长的万寿菊检测需求的问题,提出了一种改进的轻量化YOLOv5s万寿菊识别方法,并通过适宜的数据集增强技术为识别方法提供可靠的数据支撑;该方法采用Shuffle... 针对传统识别网络结构冗余且普适性低,导致推理过程复杂、效能低下,难以满足密集生长的万寿菊检测需求的问题,提出了一种改进的轻量化YOLOv5s万寿菊识别方法,并通过适宜的数据集增强技术为识别方法提供可靠的数据支撑;该方法采用ShuffleNet V2替代CSPDarknet53作为主干网络,并引入SimAM注意力机制,以减小网络规模并提升密集目标检测效能;颈部网络采用Slim-neck结构,结合GSConv和VoV-GSCSP模块提升密集目标的特征提取效率;训练过程中,使用WIoU误差函数并通过Soft-NMS动态调整边界框,以增强网络的泛化能力;算例分析及产地实测结果表明,所改进的轻量化YOLOv5s网络的平均精度均值较现有常用模型提高了3%,参数量减少了6.44 MB,每秒浮点运算次数减少了14.70 G,模型体积减少了12.24 MB,每秒帧数增加了47.19帧,且网络鲁棒性强,极大地降低了其应用与推广成本。 展开更多
关键词 万寿菊识别 轻量化模型 改进YOLOv5s模型 shuffleNet v2 注意力机制
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Measuring Recreational Value of World Heritage Sites Based on Contingent Valuation Method:A Case Study of Jiuzhaigou 被引量:9
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作者 DONG Xuewang ZHANG Jie +2 位作者 ZHI Ruizhi ZHONG Shi'en LI Min 《Chinese Geographical Science》 SCIE CSCD 2011年第1期119-128,共10页
World heritage possesses various kinds of use value and non-use value. Measuring the recreational value of world heritage sites is a key issue in the heritage tourism. This paper employs Contingent Valuation Method (C... World heritage possesses various kinds of use value and non-use value. Measuring the recreational value of world heritage sites is a key issue in the heritage tourism. This paper employs Contingent Valuation Method (CVM), which is an evaluation instrument on the basis of tourists′ attitude and preference, to measure the recreational value of Jiuzhaigou, one of the World Natural Heritage sites in China, and analyzes the biases in the survey. The results show that: 1) In 2009, Jiuzhaigou′s recreational value was 3.46×108 yuan (RMB), and the per capita Willingness to Pay (WTP) was 137.31 yuan by CVM. Compared with the results of other methods, this result is significantly low. 2) Among the factors that influence Jiuzhaigou tourists′ WTP, psychological perception factors have the greatest effect while demographic and socio-economic characteristics have a small effect on WTP. 3) The virtuality in CVM creates biases both from CVM itself and in the procedures that CVM was implemented. The former includes hypothetical bias, information bias, protest response bias, and strategic bias; and the latter includes the questionnaire design, population and sample definition, sampling and data processing. The paper analyses those biases and illustrates their potential in-fluences on the accuracy of CVM measurement. 4) Although there are various defects in CVM measurement, it is still an effective valuation method. 展开更多
关键词 Contingent valuation method (CvM) Willingness to Pay (WTP) tourist's attitude tourist's preference world heritage recreational value BIAs Jiuzhalgou
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A Family of Fifth-order Iterative Methods for Solving Nonlinear Equations 被引量:4
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作者 Liu Tian-Bao Cai Hua Li Yong 《Communications in Mathematical Research》 CSCD 2013年第3期255-260,共6页
In this paper, we present and analyze a family of fifth-order iterative methods free from second derivative for solving nonlinear equations. It is established that the family of iterative methods has convergence order... In this paper, we present and analyze a family of fifth-order iterative methods free from second derivative for solving nonlinear equations. It is established that the family of iterative methods has convergence order five. Numerical examples show that the new methods are comparable with the well known existing methods and give better results in many aspects. 展开更多
关键词 Newton's method iterative method nonlinear equation order of convergence
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A DIAGONAL SPLIT-CELL MODEL FOR THE OVERLAPPING YEE FDTD METHOD 被引量:3
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作者 Jinjie Liu Moysey Brio Jerome V. Moloney 《Acta Mathematica Scientia》 SCIE CSCD 2009年第6期1670-1676,共7页
In this paper, we present a nonorthogonal overlapping Yee method for solv- ing Maxwell's equations using the diagonal split-cell model. When material interface is presented, the diagonal split-cell model does not req... In this paper, we present a nonorthogonal overlapping Yee method for solv- ing Maxwell's equations using the diagonal split-cell model. When material interface is presented, the diagonal split-cell model does not require permittivity averaging so that better accuracy can be achieved. Our numerical results on optical force computation show that the standard FDTD method converges linearly, while the proposed method achieves quadratic convergence and better accuracy. 展开更多
关键词 FDTD method Overlapping Yee method Maxwell's equations Optical force
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Function Combined Method for Design Innovation of Children's Bike 被引量:4
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作者 WU Xiaoli QIU Tingting CHEN Huijuan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第2期242-247,共6页
As children mature, bike products for children in the market develop at the same time, and the conditions are frequently updated. Certain problems occur when using a bike, such as cycle overlapping, repeating function... As children mature, bike products for children in the market develop at the same time, and the conditions are frequently updated. Certain problems occur when using a bike, such as cycle overlapping, repeating function, and short life cycle, which go against the principles of energy conservation and the environmental protection intensive design concept. In this paper, a rational multi-function method of design through functional superposition, transformation, and technical implementation is proposed. An organic combination of frog-style scooter and children’s tricycle is developed using the multi-function method. From the ergonomic perspective, the paper elaborates on the body size of children aged 5 to 12 and effectively extracts data for a multi-function children’s bike, which can be used for gliding and riding. By inverting the body, parts can be interchanged between the handles and the pedals of the bike. Finally, the paper provides a detailed analysis of the components and structural design, body material, and processing technology of the bike. The study of Industrial Product Innovation Design provides an effective design method to solve the bicycle problems, extends the function problems, improves the product market situation, and enhances the energy saving feature while implementing intensive product development effectively at the same time. 展开更多
关键词 children’s bike function combined method ERGONOMICs function transformed
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