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On Naturalism in Stephen Crane's The Open Boat
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作者 王秀红 陈贝贝 《海外英语》 2014年第17期212-217,共6页
Stephen Crane is one of the greatest figures in the history of American literature and his novella The Open Boat is widely known by people all over the world as a representative work of Naturalism. This paper aims at ... Stephen Crane is one of the greatest figures in the history of American literature and his novella The Open Boat is widely known by people all over the world as a representative work of Naturalism. This paper aims at exploring Naturalism in Stephen Crane's The Open Boat,which will guide the readers to understand American Naturalism accurately and thoroughly. It firstly introduces the author and his novel The Open Boat. Secondly,it progressively dissects Naturalism. It not only analyses the general characteristics of Naturalism with details in The Open Boat,but also interprets the distinguishing features of American Naturalism so that readers can better understand the features of American Naturalism. Through textual perusal,it further studies the unique characteristics of Stephen Crane's Naturalism and lays particular emphasis on Crane's special concern on the awakening of humanity. It is hoped that this thesis can help readers get an in-depth comprehension of Naturalism and gain some inspiration from TheOpenBoat. 展开更多
关键词 NATURALISM Stephen CRANE the OPEN boat
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On the Writing Style of The Open Boat
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作者 张静 《英语广场(学术研究)》 2012年第9期28-29,共2页
The Open Boat is one of the best realistic stories written by Stephen Crane,an early American naturalist and impressionist writer who dramatically presents the subtle relation between man and nature as well as that of... The Open Boat is one of the best realistic stories written by Stephen Crane,an early American naturalist and impressionist writer who dramatically presents the subtle relation between man and nature as well as that of man and society.His personal experience on the sea has an enormous impact on the story.This paper tries to carry out a detailed examination of the story in the light of writing style in order to explore his unique style and the beauty of the story. 展开更多
关键词 Stephen CRANE The OPEN boat WRITING STYLE
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Dynamic Analysis of High-Speed Boat Motion Simulator by a Novel 3-DoF Parallel Mechanism with Prismatic Actuators Based on Seakeeping Trial 被引量:3
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作者 Ali Pirouzfar Javad Enferadi Masoud Dehghan 《Journal of Marine Science and Application》 CSCD 2018年第2期178-191,共14页
In this study,we focused on a novel parallel mechanism for utilizing the motion simulator of a high-speed boat(HSB).First,we expressed the real behavior of the HSB based on a seakeeping trial.For this purpose,we recor... In this study,we focused on a novel parallel mechanism for utilizing the motion simulator of a high-speed boat(HSB).First,we expressed the real behavior of the HSB based on a seakeeping trial.For this purpose,we recorded the motion parameters of the HSB by gyroscope and accelerometer sensors,while using a special data acquisition technique.Additionally,a Chebychev highpass filter was applied as a noise filter to the accelerometer sensor.Then,a novel 3 degrees of freedom(DoF)parallel mechanism(1T2R)with prismatic actuators is proposed and analyses were performed on its inverse kinematics,velocity,and acceleration.Finally,the inverse dynamic analysis is presented by the principle of virtual work,and the validation of the analytical equations was compared by the ADAMS simulation software package.Additionally,according to the recorded experimental data of the HSB,the feasibility of the proposed novel parallel mechanism motion simulator of the HSB,as well as the necessity of using of the washout filters,was explored. 展开更多
关键词 MOTION simulators Parallel mechanism HIGH-SPEED boat SEAKEEPING TRIAL INVERSE dynamics Virtualwork
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Quantifying cold front induced water transport of a bay with in situ observations using manned and unmanned boats 被引量:2
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作者 WEEKS Eddie ROBINSON Mark E LI Chunyan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第11期1-7,共7页
The generation of high-resolution data is increasingly important in understanding the complexities of coastal ocean and developing sound management strategies, especially in view of the long-term impact of severe weat... The generation of high-resolution data is increasingly important in understanding the complexities of coastal ocean and developing sound management strategies, especially in view of the long-term impact of severe weather systems. The impact of severe weather systems, when integrated over time, can be significant when compared with tidal oscillations. This paper presents a study of water transport out of Vermilion Bay in response to a short, intense event associated with a passing atmospheric cold front, and reports the application of an Acoustic Doppler Current Profiler (ADCP) mounted on an Automated Surface Craft (ASC), known as the auto-boat or unmanned boat, developed in our lab at the Louisiana State University, to generate high resolution data accurately at a fraction of the cost of a manned boat. In our study, we used a manned boat and an unmanned boat, each for over 24 h to cover an entire diurnal tidal cycle, to measure flow velocity profiles to calculate the total transport. A stationary ADCP was deployed in the Southwest Pass of the Vermilion Bay from May 2009 to April 2012, providing data almost continuously (with only one major gap), with a 717-day record of water transport between the northern Gulf of Mexico and Vermilion Bay, and demonstrates the importance of the pass in water transport. 展开更多
关键词 cold fronts unmanned boat Vermillion Bay Acoustic Doppler Current Profiler surveys regression on transport
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THE STRONG DRAGON BOAT RACE PRECIPITATION OF GUANGDONG IN 2008 AND QUASI-10-DAY OSCILLATION 被引量:2
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作者 谷德军 张维 《Journal of Tropical Meteorology》 SCIE 2012年第3期349-359,共11页
Guangdong suffered from the most serious precipitation of its corresponding time during the dragon-boat race of 2008 since 1951.The relationship between the strong dragon-boat precipitation in 2008 and atmospheric low... Guangdong suffered from the most serious precipitation of its corresponding time during the dragon-boat race of 2008 since 1951.The relationship between the strong dragon-boat precipitation in 2008 and atmospheric low-frequency oscillation was analyzed with the methods of wavelet analysis,correlation and Lanczos filter.Results showed that the daily rainfall exhibits a significant 7 to 12-day quasi-periodic oscillation(namely quasi-10-day oscillation) during the precipitation,the daily 500 hPa height over Guangdong exhibits a significant 8 to 13-day quasi-periodic oscillation,and the daily 850 hPa zonal wind averaged over the north of the South China Sea presents a significant quasi-12-day periodic oscillation.The Guangdong rainfall during the annually first rainy season is most closely correlated with monsoon over the north of South China Sea,and less closely with an upper-level trough at 500 hPa affecting Guangdong.Strong monsoon surges induced two heavy rainfall processes in 2008.The monsoon surges joined with a westward-propagating quasi-10-day oscillation that originated from the central Pacific and was enhanced in a strong convective region east of the Philippines and a northward-propagating monsoon that originated from the southern South China Sea was enhanced.With composite analysis of typical phases,the common evolution characteristics of atmospheric circulation of the two heavy rainfall processes were analyzed for different phases.These features can be used as reference for medium prediction of heavy rainfall processes in Guangdong. 展开更多
关键词 dragon-boat festival precipitation upper-level trough at 500 hPa monsoon over the north of South China Sea low-frequency oscillation
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LIFT-BOAT及其稳性特点
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作者 姜芸芸 何炎平 《中国海洋平台》 2006年第6期4-7,共4页
lift-boat是一种海洋开发中应用广泛的海洋建筑物,由于外形与功能的特殊性,使其稳性也有特殊点。在介绍lift-boat的同时,对其稳性特点进行了研究。
关键词 Lift—boat 完整稳性 破损稳性
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Improving the Use of Robotic Welding of Aluminum Boats through Modularization 被引量:1
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作者 Paul Kah Esa Hiltunen Jukka Martikainen 《Engineering(科研)》 2014年第1期42-49,共8页
The level of automation in the manufacture of recreational aluminum boats is very low. Robotized welding is rarely utilized, although it is commonly considered as the most effective way to reduce costs and increase co... The level of automation in the manufacture of recreational aluminum boats is very low. Robotized welding is rarely utilized, although it is commonly considered as the most effective way to reduce costs and increase competitiveness. A reason for the under-exploitation of robotics can be found in the construction of aluminum boats;boat models and their detailed structures are almost without exception individual pieces. A new stiffener structure for an aluminum recreational boat hull is developed in this work. Construction of the stiffener as a module allows exploitation of the advantages of modularization. The number of different parts is reduced and the structure simplified improves the applicability of robotic welding and provides benefits accruing from mass production. The same module can be used in several boat models. The modularity also makes it possible to use the same advanced robot welding fixture for a variety of boat models. 展开更多
关键词 MODULARIZATION MODULARITY DFMA Design for Manufacture and ASSEMBLY ALUMINUM WELDING Robotic WELDING Sub-Assembly boat
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Archetypal Analysis of The Open Boat
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作者 朱娟 《海外英语》 2013年第10X期196-197,227,共3页
The Open Boat is written by Stephen Crane according to his own experience of encountering a shipwreck. This short novel is not only a legend, but also a complex of the author's thinking of life and human and a fab... The Open Boat is written by Stephen Crane according to his own experience of encountering a shipwreck. This short novel is not only a legend, but also a complex of the author's thinking of life and human and a fable of men's lives. It is full of symbols and metaphors. To interpret the meaning of this novel, this paper is engaged to have an archetypal analysis of this short story. 展开更多
关键词 The OPEN boat Stephen CRANE Archetypal CRITICISM
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Comparison of the Naturalism in Sister Carrie and The Open Boat
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作者 孙雪莹 《海外英语》 2015年第10期181-181,共1页
Theodore Dreiser's Sister Carrie and Stephen Crane's The Open Boat are American naturalistic works in the 19 th centu-ry.The two novels reveal the writers' awareness of the American people's social sit... Theodore Dreiser's Sister Carrie and Stephen Crane's The Open Boat are American naturalistic works in the 19 th centu-ry.The two novels reveal the writers' awareness of the American people's social situation.This paper will analyze Sister Carrie andThe Open Boat from the point of naturalism. 展开更多
关键词 AMERICAN NATURALISM SISTER CARRIE The Open boat
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2022年华南极端“龙舟水”与大气环流及海温异常的关系 被引量:1
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作者 伍红雨 吴遥 郑璟 《大气科学学报》 CSCD 北大核心 2024年第3期450-459,共10页
利用华南192个国家气象观测站逐日降水资料,NCEP/NCAR大气环流再分析资料,NOAA月平均海表温度资料(ERSST V5)及向外长波辐射(OLR)资料,采用相关、合成分析的方法研究了2022年华南“龙舟水”异常与大气环流及海温异常的关系。结果表明,2... 利用华南192个国家气象观测站逐日降水资料,NCEP/NCAR大气环流再分析资料,NOAA月平均海表温度资料(ERSST V5)及向外长波辐射(OLR)资料,采用相关、合成分析的方法研究了2022年华南“龙舟水”异常与大气环流及海温异常的关系。结果表明,2022年“龙舟水”期间,东亚大槽、东北冷涡偏强,南下冷空气偏强,同时西太平洋副热带高压和南支槽均偏强,在华南存在明显的水汽辐合。2022年发生的拉尼娜事件,大气环流对其有明显响应,Walker环流增强,华南对流明显加强,菲律宾以东存在异常反气旋环流,副高加强导致其西北侧的西南风加强,向华南水汽输送显著增强,同时华南存在显著的上升运动。大气环流和海温的异常导致2022年华南极端“龙舟水”。 展开更多
关键词 极端“龙舟水” 华南 大气环流 海温
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基于FIA*-APF算法的蟹塘投饵船动态路径规划 被引量:1
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作者 孙月平 方正 +4 位作者 袁必康 孙杰 孟祥汶 汪彦彤 赵德安 《农业工程学报》 EI CAS CSCD 北大核心 2024年第9期137-145,共9页
为了提高无人投饵船在含障碍物河蟹养殖池塘自主巡航的作业效率和安全性,该研究提出基于改进A*算法与人工势场法相融合(fusion of improved A*and artificial potential field,FIA*-APF)的蟹塘投饵船动态路径规划算法。首先引入动态加... 为了提高无人投饵船在含障碍物河蟹养殖池塘自主巡航的作业效率和安全性,该研究提出基于改进A*算法与人工势场法相融合(fusion of improved A*and artificial potential field,FIA*-APF)的蟹塘投饵船动态路径规划算法。首先引入动态加权因子优化A*算法评价函数;其次加入转折惩罚函数并删除冗余点,接着利用B样条曲线对全局路径进行平滑处理;最后将改进A*算法得到的全局路径作为改进人工势场法中的引力路径,生成投饵船自主巡航高效路径。根据养殖池塘创建静态和动态2种仿真环境,分别对传统人工势场法(traditional artificial potential field,TAPF)、基于A*和人工势场法的融合算法(the A*and artificial potential field,TA*-APF)和FIA*-APF算法的性能进行20次测试。仿真试验结果表明:2种环境下,FIA*-APF算法的平均规划时间是TAPF算法的17.23%,是TA*-APF算法的51.96%,平均指令节点数量比TAPF算法减少50.64%,比TA*-APF算法减少65.03%,平均路径长度比TA*-APF算法减少2.82%。蟹塘试验结果表明:FIA*-APF算法的规划时间为TAPF算法的38.16%,为TA*-APF的62.42%,路径长度比TAPF算法减少29.13%,比TA*-APF减少10.15%;另外,TAPF和TA*-APF算法规划路径上大于60°的转角分别是FIA*-APF算法的3.28和2.62倍,大于100°的转角分别是FIA*-APF算法的3.73和1.67倍,该研究算法规划的路径更高效平滑。研究结果可为无人投饵船自主导航提供参考。 展开更多
关键词 无人投饵船 算法 导航 路径规划 A*算法 人工势场法 动态避障
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On the Theme of The Open Boat
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作者 Lu Yaozhong (Department of Basic Courses, Lanzhou Railway Institute, Lanzhou, 730070, China) 《兰州大学学报(社会科学版)》 CSSCI 北大核心 2000年第S1期67-69,共3页
The Open Boat is one of the best realistic stories written by stephen crane, an early American naturalist writes. At dramatically presnets the subtle, delicate relation between man and nature, cranes ideas of th... The Open Boat is one of the best realistic stories written by stephen crane, an early American naturalist writes. At dramatically presnets the subtle, delicate relation between man and nature, cranes ideas of the essence of man and nature are revelaed thorugh his analysis of the situation and experience of the protagonist. 展开更多
关键词 Stephen crane The Open boat nature
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近62 a华南“龙舟水”气候特征及变化 被引量:1
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作者 伍红雨 郭尧 吴遥 《暴雨灾害》 2024年第1期84-92,共9页
每年端午节前后龙舟竞渡之时,是华南前汛期降水最多、最为集中的时段,容易引发严重洪涝灾害,并对早稻生产造成严重影响,称之为“龙舟水”。对华南“龙舟水”期间暴雨过程的频次和强度进行研究是当前防灾减灾的迫切需求。利用1961—2022... 每年端午节前后龙舟竞渡之时,是华南前汛期降水最多、最为集中的时段,容易引发严重洪涝灾害,并对早稻生产造成严重影响,称之为“龙舟水”。对华南“龙舟水”期间暴雨过程的频次和强度进行研究是当前防灾减灾的迫切需求。利用1961—2022年华南192个国家气象观测站逐日降水资料,采用EOF、线性趋势、M-K突变等方法,分析了华南“龙舟水”期间降水量的时空特征及变化;构建了一个表征华南“龙舟水”暴雨过程的综合强度指数,由此分析华南近62 a“龙舟水”期间暴雨过程频次、强度以及“龙舟水”强度年景指数的特征和变化。结果表明,华南“龙舟水”一致性变化是其最主要的特点。1961—2022年“龙舟水”期间,华南共出现229次暴雨过程,平均每年3.7次。近62 a来华南区域平均“龙舟水”降水量和暴雨过程频次变化趋势不显著,但“龙舟水”强度年景指数以1.2·(10 a)^(-1)的速率显著上升。评估得到近62 a华南“龙舟水”最强暴雨过程出现在2022年6月4—21日,华南“龙舟水”强年有4 a,分别出现在2022年、2020年、2008年和2006年。 展开更多
关键词 龙舟水 暴雨过程 综合强度指数 气候特征 华南
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A Study on the Transformation of the Chinese Dragon Boat Festival in Japan
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作者 Qiu Lijun Zhang Qiuyue 《Contemporary Social Sciences》 2019年第2期21-32,共12页
The Japanese Dragon Boat Festival originates from China. It was first carried to Japan in the 7 th century, gradually developed into Men's Day after more than one thousand years of transformation from routine roya... The Japanese Dragon Boat Festival originates from China. It was first carried to Japan in the 7 th century, gradually developed into Men's Day after more than one thousand years of transformation from routine royal activities and female sacrificial activities, and finally converted into Children's Day today. The Japanese reform of the Chinese Dragon Boat Festival range from the types of celebrations to its meaning with regard to native customs and habits. Although the Japanese government modified and complemented the festival in various historical stages, forming a Dragon Boat Festival with Japanese characteristics, the Japanese Dragon Boat Festival is still heavily loaded with Chinese cultural elements. 展开更多
关键词 Japanese DRAGON boat FESTIVAL FARMING culture women Men's DAY Children's DAY
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Study on Band Gap Characteristics of Boat-Shaped Phononic Crystal
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作者 Jia Xu Yabing Li Youdi Kuang 《Journal of Applied Mathematics and Physics》 2022年第12期3693-3699,共7页
In this paper, we analyze the two-dimensional Boat-shaped structure based on the finite element method. We calculated its energy band structure and vibration transmission properties and found that the structure has ba... In this paper, we analyze the two-dimensional Boat-shaped structure based on the finite element method. We calculated its energy band structure and vibration transmission properties and found that the structure has band gaps at both high and low frequencies. Compared with common traditional two- dimensional phononic crystals, the boat-shaped phononic crystal has the advantage of larger bandgap design and modulation parameter space due to their structural complexity. In order to obtain better bandgap characteristics, we studied the influence of four key parameters, such as the rod length and the angle between the rods, on the bandgap. The results show that: for low frequency band gaps, the width of the band gap can be effectively changed by changing the size of the angle between the rods while rod length greatly affects the bandgap position;for high band gaps, the length of rods has a large effect on the band gap position. These laws have guiding significance for the bandgap regulation of boat-shaped phononic crystal. 展开更多
关键词 Phononic Crystal Band Gap boat-Shaped Finite Element Simulation
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Internal conflicts of Emily Dickinson—A study of the images of boat and sea in Dickinson's poems
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作者 万海艳 《海外英语》 2014年第13期184-185,187,共3页
The peculiar images,the boat and the sea,often recur in the poems of Emily Dickinson,the great American poet,which well reflect her internal conflicts,the conflicts between being an autonomous woman and being a passio... The peculiar images,the boat and the sea,often recur in the poems of Emily Dickinson,the great American poet,which well reflect her internal conflicts,the conflicts between being an autonomous woman and being a passionate yet submissive woman.In her poems,the sea is a symbol of the male-dominated society or an individual man.While the little boat is the epitome of Dickinson:sometimes it wants to be strong-willed and clear of its destination,sometimes it just wants to moor in the sea and enjoy the calmness.The paper tends to reveal the psychological struggle of Emily Dickinson and show the whole image of her as an individual through the analysis of the images of boat and sea in Dickinson’s poems. 展开更多
关键词 image boat SEA INTERNAL conflicts EMILY Dickson
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用于龙舟训练的仿生柔性触觉传感器
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作者 廖勇胜 程月 +3 位作者 李荣军 谭晶 于源 焦志伟 《塑料》 CAS CSCD 北大核心 2024年第4期40-44,60,共6页
为了提高龙舟比赛运动员的训练效果,开发了可用于身体运动识别及压力监测的仿生纤毛柔性触觉传感器。柔性触觉传感器采用了经典的基底-传感层-封装层式“三明治”结构,柔性硅胶基底采用旋涂法制备,传感层为利用Langmuir⁃Blodgett方法得... 为了提高龙舟比赛运动员的训练效果,开发了可用于身体运动识别及压力监测的仿生纤毛柔性触觉传感器。柔性触觉传感器采用了经典的基底-传感层-封装层式“三明治”结构,柔性硅胶基底采用旋涂法制备,传感层为利用Langmuir⁃Blodgett方法得到的大面积碳纳米管传感薄膜,纤毛栽种于传感层,最后封装得到具有仿生纤毛的触觉传感器。由传感器的SEM照片可知,层与层之间的结合特性较好,采用自制的往复测试平台,对传感器进行了测试。传感器耐用性最高可达5500次,最大阻值差可达300%,对于不同方向力的刺激有识别特性,可清晰识别人体的脉搏信号,对未来龙舟训练智能装备开发中的动作识别、力量监测等功能具有较大现实意义。 展开更多
关键词 龙舟训练 柔性触觉传感器 仿生纤毛 碳纳米管 方向力识别
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云南小凉山地区端午药市的民族药用植物资源研究
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作者 徐天才 陈翠 +4 位作者 康平德 戚淑威 孙恒 袁慧娟 杨少华 《中国野生植物资源》 CSCD 2024年第6期123-130,共8页
目的:了解云南小凉山地区端午药市药用植物交易现状,发掘民族医药传统知识。方法:采用民族植物学等方法对云南小凉山地区端午药市进行调查,完成包括基原名、药用部位、用途和用法等内容的药用植物编目。结果:经过整理和鉴定,云南小凉山... 目的:了解云南小凉山地区端午药市药用植物交易现状,发掘民族医药传统知识。方法:采用民族植物学等方法对云南小凉山地区端午药市进行调查,完成包括基原名、药用部位、用途和用法等内容的药用植物编目。结果:经过整理和鉴定,云南小凉山地区端午药市药用植物有153种,隶属72科,123属,被《中国药典》收录49种,作为保健品使用的药材共28种,药食同源的植物共29种。药材药用部位有8类[根类(根或块根或根茎)、全草类或全株类、果类、鳞茎、花类、子实体类、油类、叶类],其中以根类入药最多,占总种数的47.7%。药材主要用于益气补血、益肾强筋、键脾和胃、调节免疫、祛风除湿、活血祛瘀、温里散寒、温经止痛、抗炎、镇痛及清热解毒等功效。药材使用方法以水煎服为主,其次是多种配伍炖肉,煎汤熏洗或沐浴,捣烂外敷,泡酒涂擦。药材治疗疾病用于治疗消化系统最多(56种,36.6%),其次是治疗肌肉骨骼系统与结缔组织疾病(54种,35.3%)。结论:云南小凉山地区端午药市药用植物种类丰富多样,被用于药用、食用和保健品,药用独具民族特色,成为发掘新药源、新用途的潜在资源。 展开更多
关键词 民族植物 药食同源植物 端午节 小凉山地区 云南省
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基于改进YOLOv8n-seg的蟹塘水草区域分割与定位方法
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作者 孙月平 刘勇 +3 位作者 郭佩璇 李自强 孟祥汶 赵德安 《农业工程学报》 EI CAS CSCD 北大核心 2024年第17期224-233,共10页
目前蟹塘内水草清理以人工作业为主,劳动强度大,作业效率低,自动水草清理船能大幅降低劳动强度,提高作业效率,而确定蟹塘水草分布是规划水草清理船高效作业路径的关键基础。针对无人机采集的蟹塘水草图像中水草与岸边植被相似性高、难... 目前蟹塘内水草清理以人工作业为主,劳动强度大,作业效率低,自动水草清理船能大幅降低劳动强度,提高作业效率,而确定蟹塘水草分布是规划水草清理船高效作业路径的关键基础。针对无人机采集的蟹塘水草图像中水草与岸边植被相似性高、难以准确区分等问题,该研究提出一种基于改进YOLOv8n-seg的蟹塘水草区域分割与定位方法。改进模型从降低模型大小和提高召回率的角度出发,首先基于RT-DETR(real-timedetectiontransformer)的HGNetv2(hierarchical graph network)轻量化网络结构重设主干特征提取网络,缩减模型体积;其次以Efficient Rep轻量化结构为基准重构颈部网络,在降低参数量的同时增强模型的多尺度特征融合能力;接着在特征提取层引入SegNext注意力机制,加强模型对蟹塘水草区域的敏感度。为了消除模型在识别过程中产生的冗余区域,进一步提高分割精度,采用二值化处理对分割结果进行优化,并结合图像处理算法对水草区域进行面积筛选;经过坐标转换后得到精确水草轮廓经纬度坐标。试验结果表明:改进模型对蟹塘水草具有良好的区分度和分割效果,其参数量和计算量分别为1.49 M和8.4 GFLOPs,召回率和平均精度均值分别为91.5%和95.6%,与原YOLOv8n-seg模型相比,模型体积减小了49.7%,分割速度提升了32.3%。在坐标转换试验中,水草定位精度平均误差为0.22 m,验证了改进模型能够满足蟹塘水草区域分割与定位要求。研究结果为后续水草清理船自动作业路径规划研究提供参考。 展开更多
关键词 蟹塘 水草清理船 图像分割 YOLOv8n-seg 坐标转换 路径规划
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船式拖拉机直线工作参数优选研究
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作者 张超 黑晓涛 +1 位作者 瞿兆杰 张道德 《农机化研究》 北大核心 2024年第4期242-252,共11页
为提高船式拖拉机驱动性能,以单轮叶为研究对象,结合离散元法搭建了仿真模型与土槽试验平台,分析单轮叶与土壤的直线作业机理。验证仿真模型的有效性后,从单轮叶与土壤作业过程出发,对单轮叶直线作业过程受力进行了分析,发现单轮叶推进... 为提高船式拖拉机驱动性能,以单轮叶为研究对象,结合离散元法搭建了仿真模型与土槽试验平台,分析单轮叶与土壤的直线作业机理。验证仿真模型的有效性后,从单轮叶与土壤作业过程出发,对单轮叶直线作业过程受力进行了分析,发现单轮叶推进力和支撑力均随着转过角度的增加呈现先增加后降低的趋势变化。以单轮叶推进力和扭矩作为评价指标,探究单轮叶工作参数对驱动性能的影响规律,通过多因素法得到最佳的工作参数组合。研究结果表明:最优工作参数组合为入土角度11°、入土深度147mm、前进速度1.6m/s,此时轮叶推进力为172.51N、扭矩为69.82N·m,优化后的单轮叶推进力提高了40.82N,扭矩下降了34.77N·m。土槽试验表明:优化后的单轮叶损耗功率降低明显,驱动性能得到了有效提高,结果为船式拖拉机工作参数选择提供了理论依据。 展开更多
关键词 船式拖拉机 驱动性能 离散元法 单轮叶
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