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Distributional and behavioral responses of the wintering Oriental Storks to drought in China’s largest freshwater lake
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作者 Fucheng Yang Mingqin Shao Jianying Wang 《Avian Research》 SCIE CSCD 2024年第2期187-195,共9页
Extreme droughts are increasing in frequency and severity globally as a result of climate change.Developing understanding of species’responses to drought is crucial for their conservation,especially in regions experi... Extreme droughts are increasing in frequency and severity globally as a result of climate change.Developing understanding of species’responses to drought is crucial for their conservation,especially in regions experi-encing increased aridity.Although numerous studies have investigated birds’responses to drought,the emphasis has primarily been on landbirds.Drought can significantly alter the wetland environments that waterbirds inhabit,but the response of waterbirds to drought remains understudied.In this study,we surveyed the distri-bution and behavior of Oriental Storks(Ciconia boyciana)in Poyang Lake,which is the largest freshwater lake in China.Results indicate that drought-induced catchment areas at the lowest water level limited the total popu-lation size of Oriental Storks in the sub-lakes.Sub-lakes with large catchment areas at the lowest water level demonstrated a capacity to support a larger population of wintering Oriental Storks.Over time,Oriental Storks exhibited a gradual concentration in Changhu Lake,characterized by larger catchments,after resource depletion in sub-lakes with smaller catchments.Additionally,the duration of Oriental Storks’vigilance and moving be-haviors decreased significantly compared with that observed before the drought.After the drought,Oriental Storks increased their foraging efforts,as evidenced by increased presence in deeper water and reaching their heads and necks into deeper water to forage,higher search rates,but lower foraging rates.In accordance with area-restricted search theory,reductions in habitat quality resulting from drought,including extensive fish die-offs,forced Oriental Storks to increase their foraging efforts.Sustaining a specific water area in sub-lakes during droughts can preserve resource availability,which is crucial for the conservation of Oriental Storks.Imple-menting measures such as water level control and micro-modification of lake bottoms in sub-lakes might mitigate the impact of drought on the piscivorous Oriental Storks. 展开更多
关键词 Climate change Extreme drought Foraging behavior oriental stork Poyang lake
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Oriental Reed Warblers do not abandon Common Cuckoo chicks during prolonged nestling periods
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作者 Hanlin Yan Huahua Zhao +3 位作者 Haixia Luo Longwu Wang Laikun Ma Wei Liang 《Avian Research》 SCIE CSCD 2024年第3期369-373,共5页
The Oriental Reed Warbler(Acrocephalus orientalis)is one of the most commonly used hosts for the parasitic Common Cuckoo(Cuculus canorus).However,as hosts that feed unrelated parasitic nestlings may suffer extra repro... The Oriental Reed Warbler(Acrocephalus orientalis)is one of the most commonly used hosts for the parasitic Common Cuckoo(Cuculus canorus).However,as hosts that feed unrelated parasitic nestlings may suffer extra reproductive costs,they may be less willing to care for nestlings that have prolonged nestling periods.To test this hypothesis,the duration of feeding by Oriental Reed Warblers under natural conditions for their own nestlings was compared with the duration of feeding under natural conditions for Common Cuckoo nestlings and for artificially prolonged cuckoo nestlings.The results showed that Oriental Reed Warblers did not starve,drive away,or desert any of the nestlings in the experiment,and neither parent was left alone.Our experimental study indicates that both Oriental Reed Warbler parents were willing to care for nestlings with a prolonged nestling period(up to 30 days,twice the average duration time that the Oriental Reed Warblers fed their own chicks in natural conditions).However,further experiments and observations are required in other host bird species to examine whether both parents or one of the parents may exhibit the behavior of abandoning nestlings with a prolonged nestling period. 展开更多
关键词 Brood parasitism Common Cuckoo Deserted nestling oriental Reed Warbler Prolonged nestling period
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The Mechanism of Heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel
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作者 GAO Qian LI Jun +3 位作者 WANG Xianhui CAO Laifu GONG Jian LI Bo 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期275-282,共8页
Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the... Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically calculated.The effect of precipitate ripening on the Goss texture and magnetic property was investigated.Data indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate increased.Secondary recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}<227>oriented grains growing abnormally and a magnetic induction intensity of 1.90T.Furthermore,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture.However,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 T.At a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this study.The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties. 展开更多
关键词 high temperature annealing heating rate secondary recrystallization grain oriented silicon steel
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Research Progress of Occurrence and Comprehensive Control of Oriental Fruit Fly [Bactrocera dorsalis (Hendel)] 被引量:3
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作者 陈景芸 蔡平 +1 位作者 张国彪 孙振军 《Plant Diseases and Pests》 CAS 2011年第5期42-47,共6页
The paper summarizes the research progress of occurrence and comprehensive control of oriental fruit fly in the following aspects : biological and ecological characteristics, assessment of the risk and suitability, d... The paper summarizes the research progress of occurrence and comprehensive control of oriental fruit fly in the following aspects : biological and ecological characteristics, assessment of the risk and suitability, dynamic monitoring and control index, and comprehensive control methods. 展开更多
关键词 oriental fruit fly OCCURRENCE Comprehensive control China
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Analysis on Suitable Distribution Area of Oriental Fruit Fly (Bactrocera dorsalis) Based on GARP Ecological Niche Model
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作者 刘建宏 熊小真 +2 位作者 杨丽英 熊忠平 潘涌智 《Plant Diseases and Pests》 CAS 2010年第6期34-38,共5页
[Objective] The paper was to provide the scientific basis for effective monitoring and early warning on oriental fruit fly in Jiangxi Province.[Method] Using the distribution data and environmental factor data of orie... [Objective] The paper was to provide the scientific basis for effective monitoring and early warning on oriental fruit fly in Jiangxi Province.[Method] Using the distribution data and environmental factor data of oriental fruit fly,the potential distribution area of oriental fruit fly in Jiangxi Province was predicted by GARP ecological niche model.[Result]The total suitable area for oriental fruit fly in Jiangxi province was over two thirds of the whole province.Most areas in southern Jiangxi basin ranged from 24° to 26° N were the high suitable area for oriental fruit fly,where the annual average temperature was 19-20℃.Part areas in north Ganzhou and small areas in southwest Ji'an,Wuzhou,Yingtan,southeast Shangrao ranged from 26° to 27° N were the moderate suitable areas for oriental fruit fly,where the annual average temperature was 18-19℃.The low suitable area was ranged from 26° to 30° N including Binhu,Ganjiang River,Wuhe,Yuanshui area and Southwestern Mountain of Jiangxi Province,where the annual average temperature was 17-18℃.Northeast and northwest areas in Jiangxi Province and coastal areas along the Yangtze River was predicted to be non-suitable area for oriental fruit fly,where the annual average temperature was 16-17℃.[Conclusion] The results showed that the actual distribution of oriental fruit fly basically was consistent with the distribution predicted by GARP. 展开更多
关键词 oriental fruit fly GARP Potential distribution area JIANGXI
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Study on Integrated Control against Oriental Fruit Fly[Bactrocera dorsalis(Hendel)] in Guava Orchard
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作者 雷艳梅 廖冬晴 +1 位作者 黄树长 谢荔元 《Plant Diseases and Pests》 CAS 2011年第2期47-50,共4页
[ Objective ] The paper was to explore the damage, occurrence pattern and integrated control methods of oriental fruit fly [ Bactrocera dorsalis ( Hen- del) ] in Nanning region of Guangxi Province. [ Method ] Using ... [ Objective ] The paper was to explore the damage, occurrence pattern and integrated control methods of oriental fruit fly [ Bactrocera dorsalis ( Hen- del) ] in Nanning region of Guangxi Province. [ Method ] Using fixed system survey method, with fruit fly attractants as the materials, the occurrence dynamic of oriental fruit fly adult in guava orchard was investigated. The control effects of the methods such as fruit fly attractants, fruit bagging, cleaning park to pick up fallen fruit and timely spraying pesticide against the pest were also studied. [ Result] Oriental fruit fly had two damage peak periods in Nanning region of Guangxi Prov- ince (May to June, August to September). Through the integrated control measures of trapping agent for male flies, timely spraying, fruit bagging and cleaning park to pick up fallen fruit, the population density in guava orchard dropped significantly. The fruit damage rates of guava in research base were only 6.67% -7.33% during the peak period of oriental fruit fly in June 2008, while they were 90.53% -98.00% in control area, obtaining good control effect against the pest. [ Con- dttalon ] The method used in the study preliminarily restored the yield losses of guava, which also provided basis for the preparation of overall strategy against orien- tal fruit fly in the region. 展开更多
关键词 GUAVA oriental fruit fly Integrated control
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Brood parasitism on the Yellow-rumped Flycatcher (Ficedula zanthopygia) by the Oriental Cuckoo (Cuculus optatus) in an artificial nestbox in Beijing 被引量:1
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作者 邓文洪 《Chinese Birds》 CSCD 2013年第2期187-188,共2页
The artificial nestbox on an Asian White Birch (Betula platyphylla) (1360 m in elevation) was used by a pair of Yellow-rumped Flycatcher (Ficedula zanthopygia) in Beijing, and five eggs were found in the nest in 2005.... The artificial nestbox on an Asian White Birch (Betula platyphylla) (1360 m in elevation) was used by a pair of Yellow-rumped Flycatcher (Ficedula zanthopygia) in Beijing, and five eggs were found in the nest in 2005. One was much larger and was identified as the Oriental Cuckoo’s (Cuculus optatus) egg. 展开更多
关键词 nestbox oriental Cuckoo Yellow-rumped Flycatcher
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Population Quantity Variations of Oriental Fruit Fly (Bactrocera dorsalis Hendel) on the Basis of Stepwise Regression Analysis
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作者 张丽莲 杨林楠 杨仕生 《Plant Diseases and Pests》 CAS 2010年第2期32-34,共3页
[Objective] The research aimed to study the significant influence factors of the population variations of oriental fruit fly. [Method] Using stepwise regression analysis, the population variations law of oriental frui... [Objective] The research aimed to study the significant influence factors of the population variations of oriental fruit fly. [Method] Using stepwise regression analysis, the population variations law of oriental fruit fly in Jianshui County of Yunnan province and the meteorological factors that caused its occurrence were analyzed. And the regression model was built. Finally, the regression model was tested on the basis of the data in Jianshui County of Yunnan Province during 2004-2006.[Result] The main meteorological factors that influenced the occurrence of oriental fruit fly were relative humidity, the lowest monthly temperature and rainfall. [Conclusion] This study will provide certain reference for the prediction researches on the time, quantity and occurrence peak of oriental fruit fly. 展开更多
关键词 oriental fruit fly Stepwise regression analysis Meteorological factors
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Control Study of Parasitic Pyemotes sp.against Oriental Fruit Moth(Grapholitha molesta Bussck)
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作者 周巍 钟汉东 +3 位作者 黄和平 董立坤 欧克芳 李传仁 《Plant Diseases and Pests》 CAS 2011年第1期31-34,共4页
[ Objective] The paper was to study the parasitic ability and field control effect of Pyemotes sp. against oriental fruit moth (Grapholitha molesta Bussck) which caused damage on Photinia. [ Method] The indoor infec... [ Objective] The paper was to study the parasitic ability and field control effect of Pyemotes sp. against oriental fruit moth (Grapholitha molesta Bussck) which caused damage on Photinia. [ Method] The indoor infection test and field control test of Pyemotes sp. against oriental fruit moth was carried out. The parasitic ability and activity characteristic of Pyemotes sp. were observed, and the effect of environmental factors such as humidity and temperature on the para- sitic ability of Pyemotes sp. was studied. [Result] Pyemotes sp. had good control effect on oriental fruit moth under the proper conditions; the host searching abili- ties of Pyemotes sp. were different at different temperature and humidity conditions, humidity had large impact on the activity of Pyemotes sp., while temperature had large impact on the individual activity. [ Conclusion] The result showed that Pyemotes sp. had effective control effort on oriental fruit moth. 展开更多
关键词 Pyemotes sp. Biological control oriental fruit moth
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Breeding of a New Cucumber F_1 Hybrid ‘Oriental Show’
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作者 吴小波 周海霞 +1 位作者 郭竞 李芳霞 《Agricultural Science & Technology》 CAS 2016年第12期2809-2810,2814,共3页
‘Oriental Show’ is a generation of new cucumber variety, with the superi-or inbred line ‘101’ as the female parent and inbred line ‘102’ as the male par-ent. The growth vigor tends to be strong and the first fem... ‘Oriental Show’ is a generation of new cucumber variety, with the superi-or inbred line ‘101’ as the female parent and inbred line ‘102’ as the male par-ent. The growth vigor tends to be strong and the first female blossom produces on the 4th or the 5th internode. Fruit is 34 cm long and 32 cm in transverse diameter. Per fruit weighs about 230 g. lt is dark green, densely covered with thorns. lt tastes crisp, containing 167.7 mg/kg Vc, and it is resistant to downy mildew, pow-dery mildew and bacterial angular leaf spot disease. lt is yielding and tolerant to low temperature and weak luminance. The yield can be as high as over 112 443.778 kg/hm^2, and ‘Oriental Show’ is suitable to be cultivated in greenhouses in early spring or solar greenhouses in north China or Henan province. 展开更多
关键词 CUCUMBER oriental Show' - F -hybrid-
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Control Effects of Several Technical Measures on Overwintering Generation of Oriental Fruit Moth in Peach Orchard
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作者 王越辉 白瑞霞 +3 位作者 马之胜 贾云云 李海山 马铭泽 《Agricultural Science & Technology》 CAS 2016年第5期1177-1180,共4页
Peeling trunk,binding insect-attracting belt,cleaning orchard and soil-covering under the crown were the control methods on overwintering generation of oriental fruit moth.However,they had not been applied widely on t... Peeling trunk,binding insect-attracting belt,cleaning orchard and soil-covering under the crown were the control methods on overwintering generation of oriental fruit moth.However,they had not been applied widely on the production because of the lack of systematic quantitative evaluation.Aiming at this fact,the control effects of these technical measures were studied in peach with different ripening period.The results showed that peeling trunk was the best with the control effect of88.64%.The control effect of binding insect-attracting belt of grass bundle was74.13%,which was the most economical and efficient.Covering with soil layer of 3cm under the crown during the middle ten days of March could holdback the adult getting out from soil.Cleaning deadwood could clean out the overwintering larvae on the ground. 展开更多
关键词 Peach orchard oriental fruit moth Overwintering generation Control method
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Effect of Phytohormones on Adventitious Bud Differentiation from Bulb Scales of Oriental Lily Test-tube Plantlets
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作者 王菲彬 王斐 +1 位作者 管玲玲 胡凤荣 《Agricultural Science & Technology》 CAS 2013年第10期1365-1368,1382,共5页
[Objective] The purpose of this study is to investigate the effects of differ- ent phytohormones on the adventitious bud differentiation of oriental lily. [Method] The bulb scales of the test-tube plantlets of Tiber, ... [Objective] The purpose of this study is to investigate the effects of differ- ent phytohormones on the adventitious bud differentiation of oriental lily. [Method] The bulb scales of the test-tube plantlets of Tiber, Rodina and Constanta were cul- tured in media supplemented with different cytokinin and auxin at different concen- tration, and then the adventitious buds in each treatment were calculated. [Result] Cytokinins had different influence on the adventitious bud differentiation of the three oriental lily cultivars. Among them, 6-BA had the best effect to induce the adventi- tious bud differentiation from bulb scales of Tiber and Rodina, but there was some difference in the optimal concentration. KT had the best effect to induce the adven- titious bud differentiation of Constanta. The auxins had little influence on the quality of the adventitious bud of the three oriental lily cultivars, but caused some difference in differentiation coefficients. [Conclusion] The most suitable media for the adventi- tious bud differentiation from bulb scales in vitro of Tiber, Rodina and Constanta were MS+0.2 mg/L 6-BA+0.2 mg/L 2,4-D, MS+I.0 mg/L 6-BA+0.2 mg/L IAA, MS+ 1.0 mg/L KT+0.5 mg/L 2,4-D, respectively. 展开更多
关键词 oriental lily Bulb scales of test-tube plantlets PHYTOHORMONE Tissue culture
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山斑鸠Streptopelia orientalis在西藏拉萨市郊的繁殖生态 被引量:2
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作者 普布 巴桑 +1 位作者 拉多 次仁 《西藏大学学报(社会科学版)》 2008年第6期26-31,共6页
山斑鸠在拉萨地区是一种夏候鸟,每年的4月初开始迁入拉萨。它们在人工林、沙棘林和高山灌丛营巢和夜宿,以林间空地、农田、河滩以及荒地为主要的取食地。巢置于较高的树木或郁闭度大的树上,4月底开始筑巢,营巢期一般为6-8d左右;巢平均... 山斑鸠在拉萨地区是一种夏候鸟,每年的4月初开始迁入拉萨。它们在人工林、沙棘林和高山灌丛营巢和夜宿,以林间空地、农田、河滩以及荒地为主要的取食地。巢置于较高的树木或郁闭度大的树上,4月底开始筑巢,营巢期一般为6-8d左右;巢平均大小为21.85(16-27)cm×3.07(2-4)cm,离地高为350(200-527)cm,巢重为54.3g(52-64)。5月初产卵,日产一枚,平均窝卵数为2枚(21巢),卵平均重量为10.36g(8.5-12),平均大小为33.27(27-37)×22.6(23-26)mm。孵化期为16-17d,13巢的统计平均孵化率仅为60%。育雏期为16-18d,离巢率为56%。雌雄鸟均参加孵卵和育雏。人为干扰和不良的天气是影响巢成功率的主要因子。 展开更多
关键词 山斑鸠 繁殖生态 拉萨市郊
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An Analysis of the Performance of Orientalism in A Passage to India and the Exorcization of Orientalism in Maxine Hong Kingston's Works
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作者 王雪莲 《英语广场(学术研究)》 2011年第Z4期24-25,共2页
This thesis tries to study two novels:firstly,the performance of Orientalism in the novel A Passage to India;secondly the Exorcization of Orientalism in the novel the Woman Warrior written by Maxine Hong Kingston.
关键词 orientalISM A PASSAGE to INDIA Exorcization of orientalISM the WOMAN Worrior
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A Provisional Species Checklist of the Oriental Orthogoninae (Coleoptera:Caraboidea)
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作者 田明义 THIERRY Deuve 《Entomotaxonomia》 CSCD 北大核心 2010年第B08期137-148,共12页
A provisional species checklist of the Oriental subfamily Orthogoninae is provided. Orthogonius dupuisi Tian et Deuve, 2006 (from Indonesia) is treated as a junior homonym of O. dupuisi Basilewsky, 1948 (from Rhode... A provisional species checklist of the Oriental subfamily Orthogoninae is provided. Orthogonius dupuisi Tian et Deuve, 2006 (from Indonesia) is treated as a junior homonym of O. dupuisi Basilewsky, 1948 (from Rhodesia), and therefore O. dupuisianus n. nom. is proposed. Actenocus punctatus Tian et Deuve, 2006 is confirmed as a good species, rather than a junior synonym of Orthogonius crassicrus Chaudoir, 1871 proposed by Kirschenhofer (2010). 展开更多
关键词 COLEOPTERA Caraboidea Orthogoninae CHECKLIST oriental HOMONYMY
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一种改进Oriented RepPoints的遥感图像有向目标检测
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作者 谢国波 张家源 +1 位作者 林志毅 廖文康 《小型微型计算机系统》 CSCD 北大核心 2024年第11期2725-2731,共7页
为解决Oriented RepPoints算法在遥感图像有向目标检测中因遥感图像背景干扰信息较多和目标尺度大小不一所导致的检测精度不高、易漏检误检等问题,提出一种改进Oriented RepPoints的遥感图像有向目标检测方法MA-RPDet(Mixed Attention R... 为解决Oriented RepPoints算法在遥感图像有向目标检测中因遥感图像背景干扰信息较多和目标尺度大小不一所导致的检测精度不高、易漏检误检等问题,提出一种改进Oriented RepPoints的遥感图像有向目标检测方法MA-RPDet(Mixed Attention RepPoints Detector).首先,采用了PVTv2作为主干网络,该网络利用线性空间缩减自注意力机制提取出更具局部连续性的特征图,并保持与卷积运算类似的线性复杂度.其次,在特征融合阶段设计了串联性混合注意力模块,进一步强化了重要特征,促进了多尺度特征的高效交互.最后,引入平滑GIoU损失函数对模型学习策略进行优化,提高了检测精度.在两个遥感图像目标检测数据集DOTA和HRSC2016上的实验结果表明,所提方法的检测精度mAP分别达到了77.19%和90.3%,均高于其他对比算法,证明了本文方法的有效性. 展开更多
关键词 遥感图像 有向目标检测 oriented RepPoints 注意力机制 损失函数
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Oriental一词慎用为好
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作者 周立华 《语言教育》 2002年第7期31-31,共1页
《英语知识》2002年第4期p.17“话说Orient(东方)”一文中提到Oriental一词在欧洲人心目中有相当的位置,似乎含有褒义而2002的4月27日《参考消息》时事纵横栏目在“美官方文件将禁用歧视亚裔人词汇”一文中,特别指出:“Oriental这个词... 《英语知识》2002年第4期p.17“话说Orient(东方)”一文中提到Oriental一词在欧洲人心目中有相当的位置,似乎含有褒义而2002的4月27日《参考消息》时事纵横栏目在“美官方文件将禁用歧视亚裔人词汇”一文中,特别指出:“Oriental这个词从历史意义上讲含贬义。出生于香港,目前在华盛顿大学任种族研究问题教授的康妮·苏说:“他们可以叫我们easterner(东方人)。我们不介意这个词。但‘Oriental’这个词让我们感到自已低人一等,感到自己是外来人口。” 展开更多
关键词 《参考消息》 官方文件 文中 oriental 康妮 华盛顿大学 美臀 沈说 州议会
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Manifestations of Orientalism in The Joy Luck Club 被引量:1
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作者 周超波 张月佳 邴婷婷 《海外英语》 2013年第11X期231-232,共2页
Amy Tan is a renowned Chinese American writer who has won prestigious awards and also received various criticism from home and abroad. Her first novel The Joy Luck Club has won her several prestigious literary awards.... Amy Tan is a renowned Chinese American writer who has won prestigious awards and also received various criticism from home and abroad. Her first novel The Joy Luck Club has won her several prestigious literary awards. However, the limitation of Orientalism is also manifested in the novel, which leads to much criticism. It is believed that the novel is popular because the binary distinction between the East and the West satisfies the ideological needs of the white-dominated society. This thesis is trying to interpret The Joy Luck Club from the perspective of Orientalism. 展开更多
关键词 Amy TAN orientalISM The JOY LUCK CLUB Other
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Co-Treatment of EFF and 1-MCP for Enhancing the Shelf-Life and Aroma Volatile Compounds of Oriental Sweet Melons(Cucumis melo var.makuwa Makino) 被引量:11
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作者 BAI Xiao-hang TENG Lu-hua +1 位作者 Lü De-qing QI Hong-yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第1期217-227,共11页
Compared to other melon types, oriental sweet melon (Cucumis melo var. makuwa Makino) is quite a different species with a shorter shelf-life due to its typical climacteric behavior and thin pericarp. The purpose of ... Compared to other melon types, oriental sweet melon (Cucumis melo var. makuwa Makino) is quite a different species with a shorter shelf-life due to its typical climacteric behavior and thin pericarp. The purpose of this experiment is to explore the effects of co- treatment of enhanced freshness formulation (EFF) and 1-methylcyclopropene (1-MCP) on physiological changes and the content of aroma volatile compounds introduced by them of two oriental sweet melon cultivars (Yumeiren and Tianbao) during storage. The melons were stored in incubators with temperature of 15~C and a relative humidity of 85% for 24 d during which fruit quality and related physiological index were measured. Compared to the control, both treatments delayed fruit weight loss rate and kept the fruit firmness, water content and soluble solids content. Ascorbate peroxidase (APX) and phenylalanine ammonia lyase (PAL) activities showed fluctuations in treated melons, while lipoxygenase (LOX) activity (P〈0.01) and malondialdehyde (MDA) content (P〈0.05) decreased compared to control. During the early stage of storage, alcohols and aldehydes were the main volatile compounds, and esters gradually increased during storage. Of all the esters, acetic esters were the main components, followed by oxalic acid esters and other esters. The total content of aroma volatile compounds, esters, alcohols and aldehydes of co-treated melons were all higher than those of 1-MCP treated and control melons. In addition, the aroma volatile peak of co-treated melons occurred later than that of 1-MCP treated and control melons. In summary, co-treatment of EFF and 1-MCP was more beneficial than 1-MCP treatment to delay ripening and senescence, maintain fruit quality, enhance shelf-life and improve levels of aroma volatile compounds. 展开更多
关键词 oriental sweet melon enhanced freshness formulation l-methylcyclopropene aroma volatile compounds shelf-life
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基于改进Oriented R-CNN的旋转框麦穗检测与计数模型 被引量:1
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作者 于俊伟 陈威威 +2 位作者 郭园森 母亚双 樊超 《农业工程学报》 EI CAS CSCD 北大核心 2024年第6期248-257,共10页
为对干扰、遮挡等复杂的田野环境中麦穗进行精准定位与计数,该研究提出了一种改进的Oriented R-CNN麦穗旋转框检测与计数方法,首先在主干网络中引入跨阶段局部空间金字塔(spatial pyramid pooling cross stage partial networks,SPPCSPC... 为对干扰、遮挡等复杂的田野环境中麦穗进行精准定位与计数,该研究提出了一种改进的Oriented R-CNN麦穗旋转框检测与计数方法,首先在主干网络中引入跨阶段局部空间金字塔(spatial pyramid pooling cross stage partial networks,SPPCSPC)模块扩大模型感受野,增强网络感知能力;其次,在颈网络中结合路径聚合网络(PANet,path aggregation network)和混合注意力机制(E2CBAM,efficient two convolutional block attention module),丰富特征图包含的特征信息;最后采用柔性非极大值抑制算法(Soft-NMS,soft-non maximum suppression)优化预测框筛选过程。试验结果显示,改进的模型对复杂环境中的麦穗检测效果良好。相较原模型,平均精确度均值mAP提高了2.02个百分点,与主流的旋转目标检测模型Gliding vertex、R3det、Rotated Faster R-CNN、S2anet和Rotated Retinanet相比,mAP分别提高了4.99、2.49、3.94、2.25和4.12个百分点。该研究方法利用旋转框准确定位麦穗位置,使得框内背景区域面积大幅度减少,为实际观察麦穗生长状况和统计数量提供了一种有效的方法。 展开更多
关键词 图像识别 作物 注意力机制 麦穗 oriented R-CNN
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