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Black swans as sentinel species for the emergence of clade 2.3.4.4b highly pathogenic avian influenza(H5N1)in Shanghai,China,2024
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作者 Yuting Xu Shihai Wu +10 位作者 Lei Ji Jie Hu Jin Wang Ke Li Yue Yuan Gaojian Li Guangjian Zhu Panyu Hua Qiuhong Miao Hongxuan He Guimei He 《Virologica Sinica》 2025年第5期853-855,共3页
Dear Editor,Since 2024,the clade 2.3.4.4b highly pathogenic avian influenza(HPAI)H5N1 viruses have been identified in dairy cattle in the United States,raising global concerns about public health(Neumann and Kawaoka,2... Dear Editor,Since 2024,the clade 2.3.4.4b highly pathogenic avian influenza(HPAI)H5N1 viruses have been identified in dairy cattle in the United States,raising global concerns about public health(Neumann and Kawaoka,2024).As of December 18,2024,the U.S.Centers for Disease Control and Prevention(CDC)has reported over 61 confirmed cases of H5N1 infection in humans,predominantly associated with exposure to infected poultry or dairy cattle(U.S.Centers for Disease Control and Prevention,2024).Notably,the circulating 2.3.4.4b H5N1 clade has demonstrated continuous evolution in both wild and domestic birds globally,with expanding mammalian host tropism that now includes swine,cats,red foxes,harbor seals,and skunks(Peacock et al.,2024).These viruses have not only incurred substantial economic impacts but also posed dual threats to human health and ecological stability particularly during co-infections with other viruses(Abolnik,2024;Wang and Wang,2023). 展开更多
关键词 black swans clade b dairy cattle avian influenza H N sentinel species infected poultry dairy cattle uscenters
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Aggressive behavioural interactions between swans(Cygnus spp.)and other waterbirds during winter:a webcam-based study 被引量:1
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作者 Kevin A.Wood Phoebe Ham +2 位作者 Jake Scales Eleanor Wyeth Paul E.Rose 《Avian Research》 CSCD 2020年第3期310-325,共16页
Background:Our understanding of any impacts of swans on other waterbirds(including other swans),and potential effects on waterbird community structure,remain limited by a paucity of fundamental behavioural and ecologi... Background:Our understanding of any impacts of swans on other waterbirds(including other swans),and potential effects on waterbird community structure,remain limited by a paucity of fundamental behavioural and ecological data,including which species swans interact aggressively with and how frequently such interactions occur.Methods:Behavioural observations of aggression by swans and other waterbirds in winters 2018/2019 and 2019/2020,were carried out via live-streaming webcams at two wintering sites in the UK.All occurrence sampling was used to identify all aggressive interactions between conspecific or heterospecifics individuals,whilst focal observations were used to record the total time spent by swans on aggressive interactions with other swans.Binomial tests were then used to assess whether the proportion of intraspecific aggressive interactions of each species differed from 0.5(which would indicate equal numbers of intraspecific and interspecific interactions).Zero-inflated generalized linear mixed effects models(ZIGLMMs)were used to assess between-individual variation in the total time spent by swans on aggressive interactions with other swans.Results:All three swan species were most frequently aggressive towards,and received most aggression from,their conspecifics.Our 10-min focal observations showed that Whooper(Cygnus cygnus)and Bewick’s Swans(C.columbianus bewickii)spent 13.8±4.7 s(means±95%CI)and 1.4±0.3 s,respectively,on aggression with other swans.These durations were equivalent to 2.3%and 0.2%of the Whooper and Bewick’s Swan time-activity budgets,respectively.Model selection indicated that the time spent in aggressive interactions with other swans was best-explained by the number of other swans present for Whooper Swans,and an interactive effect of time of day and winter of observation for Bewick’s Swans.However,the relationship between swan numbers and Whooper Swan aggression times was not strong(R2=19.3%).Conclusions:Whilst swans do exhibit some aggression towards smaller waterbirds,the majority of aggression by swans is directed towards other swans.Aggression focused on conspecifics likely reflects greater overlap in resource use,and hence higher potential for competition,between individuals of the same species.Our study provides an example of how questions relating to avian behaviour can be addressed using methods of remote data collection such as live-streaming webcams. 展开更多
关键词 AGGRESSION Agonistic behaviour Bewick’s swans Intraspecific versus interspecific competition Remote data collection WATERFOWL Whooper swans
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Swans与惠威的合作
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《电声技术》 北大核心 2004年第9期76-77,共2页
关键词 swans公司 惠威公司 音箱 发展策略
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Swans经典产品
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《音响世界》 2004年第7期49-52,共4页
关键词 swans公司 扬声器 产品介绍 GEMINI TAURUS ALLURE
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超级扬声器,超级梦系统--Frank Hale先生畅谈惠威旗舰Swans 2.2
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《音响世界》 2003年第4期16-19,共4页
采用等磁场带式科技的惠威旗舰Swans 2.2,无可争议地成为了惠威在CES、T.H.E Show两个知名大展上最靓声的明星产品,而旗舰Swans2.2则由以惠威高级设计师--Frank Hale先生为主的设计小组开发的。作为国际电声界著名的设计大师,Frank H... 采用等磁场带式科技的惠威旗舰Swans 2.2,无可争议地成为了惠威在CES、T.H.E Show两个知名大展上最靓声的明星产品,而旗舰Swans2.2则由以惠威高级设计师--Frank Hale先生为主的设计小组开发的。作为国际电声界著名的设计大师,Frank Hale先生也亲自主持设计了如M1、M4000HT、豪庭一号等惠威的经典产品。那么,大师眼中的旗舰Swans2.2又如何呢?为此,我们对他进行了采访。以下是记者同Frank Hale先生关于旗舰Swans 2.2的谈话记录: 展开更多
关键词 惠威公司 超级扬声器 swans2.2 音箱设计 单元结构 摆位设置
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还原音乐厅 惠威旗舰SWANS 2.2落地式音箱
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作者 伍海 《视听技术》 2003年第2期26-28,共3页
能够充分地再现和还原出音乐厅现场的听感,百分之百地模拟出录音时的所有声音和音场效果,相信是每个音响音乐爱好者们的终极目标。然而,要做到这一点真的太难,首先最重要的一点就是:普通的书架箱或中等大小的落地箱,由于其物理局限,再... 能够充分地再现和还原出音乐厅现场的听感,百分之百地模拟出录音时的所有声音和音场效果,相信是每个音响音乐爱好者们的终极目标。然而,要做到这一点真的太难,首先最重要的一点就是:普通的书架箱或中等大小的落地箱,由于其物理局限,再现不出现场那种高、宽、深的音场、庞大的动态和足够大的音压级。因此,采用大型落地式音箱,用输出功率强大的功放推动,就成为达到这一目标的必由之路了。 国内著名音箱及喇叭单元制作商惠威的旗舰Swans系列音箱就是以这一考量进行设计制造的产品,已推出的旗舰2号和3号箱体高度均接近或超过2m,采用多组单元并联工作,带式高音单元或中音单元,配合有源超低音箱体,其中旗舰2号更采用了准双极结构的单元设置。庞大的动态、真实的音场、充足的音压,成为了大型听音室、大厅、会议室器材的首选对象。 展开更多
关键词 惠威公司 技术规格 swans2.2 落地式 音箱
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杜希天鹅Swans MS4
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《现代音响技术》 1999年第3期46-46,共1页
关键词 扬声器系统 swans MS4 等磁场带式 R2C
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听Frank Hale先生讲Swans(天鹅)的故事
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《音响世界》 2004年第7期46-48,共3页
与Frank Hale先生相识是在CES大展上,在此之前,对Swans的印象只是来自台湾、香港及美国的一些音响刊物的介绍及广告上,虽然也听过几对Swans的音箱,只是觉得声音不错,似乎印象并不深刻,这在上世纪90年代实在是很正常的事。因为对... 与Frank Hale先生相识是在CES大展上,在此之前,对Swans的印象只是来自台湾、香港及美国的一些音响刊物的介绍及广告上,虽然也听过几对Swans的音箱,只是觉得声音不错,似乎印象并不深刻,这在上世纪90年代实在是很正常的事。因为对中国大陆而言,那是发烧音响最活跃、市场又最富激情及商业活动最繁盛的时期。 展开更多
关键词 swans公司 扬声器 发展历程 惠威集团
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惠威Swans 2.2音箱
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《现代音响技术》 2003年第5期11-11,共1页
关键词 惠威公司 swans2.2 音箱 等磁场带式高音
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惠威Swans2.2音箱
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作者 秦观 《现代音响技术》 2003年第7期17-17,共1页
关键词 惠威公司 swans2.2 音箱 多单元线性声源排列结构 等磁场带式技术
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Migration routes and differences in migration strategies of Whooper Swans between spring and autumn 被引量:1
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作者 Ji-Yeon Lee Hyung-Kyu Nam +10 位作者 Jin-Young Park Seung-Gu Kang Nyambayar Batbayar Dong-Won Kim Jae-Woong Hwang Otgonbayar Tsend Tseveenmyadag Natsagdorj Jugdernamjil Nergui Tuvshintugs Sukhbaatar Wee-Haeng Hur Jeong-Chil Yoo 《Avian Research》 SCIE CSCD 2023年第3期345-353,共9页
Long-distance migratory birds travel more rapidly in spring than in autumn,as they face temporal breeding constraints.However,several species travel slower in spring owing to environmental influences,such as food avai... Long-distance migratory birds travel more rapidly in spring than in autumn,as they face temporal breeding constraints.However,several species travel slower in spring owing to environmental influences,such as food availability and wind conditions.GPS trackers were attached to 17 Whooper Swans(Cygnus cygnus) inhabiting northeastern Mongolia,to determine their migration routes and stopover sites in spring and autumn.Differences between spring and autumn migrations,migration-influencing parameters,and the effect of spring stopover site temperatures were analyzed.Six swans completed perfect tours between their wintering and breeding sites,and these data were used for analysis.Spring migration lasted 57 days,with 49.2 days spent at 3.7 stopover sites.Autumn migration lasted 21.5 days,with 17.5 days spent at 1.0 stopover sites.Thus,the swans traveled more rapidly in autumn than in spring.Migration distance,number of stopovers,migration speed,and straightness were important migration determinants in both spring and autumn.Migration distance,stopover duration,number of stopovers,daily travel speed,travel duration,and migration speed differed significantly between spring and autumn.During spring migration,the temperature at the current stopover sites and that at the future stopover sites displayed significant variations(t=1585.8,df=631.6,p <0.001).These findings are critical for the conservation and management of Whooper Swans and their key habitats in East Asian regions,and the data are anticipated to make a particularly significant contribution toward developing detailed management plans for the conservation of their key habitats. 展开更多
关键词 Key stopover sites Migration characteristics Migration route Migration strategy Tracking Whooper Swan
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The Status and Conservation of Whooper Swans (Cygnus cygnus) in China 被引量:1
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作者 袁力 李晓民 +4 位作者 于洪贤 郭丽滨 张太忠 高庆军 曾代华 《Journal of Forestry Research》 SCIE CAS CSCD 1997年第4期235-239,共5页
There are five Species of swan in the world. Three of them were recorded in China. They are whooper swan(Cygnus cygnus ). whistling swan (Cygnus columbianus ) and mute swan (Cygnus olor). Among them. whooper swan is t... There are five Species of swan in the world. Three of them were recorded in China. They are whooper swan(Cygnus cygnus ). whistling swan (Cygnus columbianus ) and mute swan (Cygnus olor). Among them. whooper swan is themost famous in China. Whooper swan is a resident bird in China. They breed in Xinjiang Ugyur Autonomous Region. InnerMongol Autonomous Region, Hcilongiiang Province. etc.. and winter in Qinghai. Shandong. Henan Provincc. etc.. and thelower reaches of the Changjiang River. The total number in China is about 5.000 in breeding grounds and 15.000 in winter-ing grounds. Higher number Were found in 1960s. Because of the changes in environment and hunting, of picking up eggsand of catching nestlings. their population is being reduced rapidly. They are in danger now. In order to protect the whooperswans. some protection measuresmust be taken. such as strcngthening public education and scientitic research- establishinga base of raising and breeding; deieloping intcrnational cooperation. strengthening the construction of natural reserves in thebreeding and wintering grounds. Up to the cnd of 1993. 34 natural reserves have been established in China. 展开更多
关键词 Whooper SWAN CYGNUS CYGNUS STATUS CONSERVATION China
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基于SWAN模型的波浪能发电站选址研究
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作者 孙单勋 杨智聪 +3 位作者 王卓恒 綦晓 邓慧 欧阳建友 《太阳能学报》 北大核心 2026年第1期730-737,共8页
针对现有波浪能电站选址策略单一的问题,提出一种基于SWAN数值模拟模型和平准化度电成本模型的新型波浪能电站选址策略,并应用研究区域的实际数据验证了该方法的可行性;为了进一步解决波浪能电站并网后可能对电网造成的不稳定性问题,采... 针对现有波浪能电站选址策略单一的问题,提出一种基于SWAN数值模拟模型和平准化度电成本模型的新型波浪能电站选址策略,并应用研究区域的实际数据验证了该方法的可行性;为了进一步解决波浪能电站并网后可能对电网造成的不稳定性问题,采用BiTCN-BiGRU-Attention组合神经网络对最佳选址点的发电功率进行短期预测,可提高波浪能电站后期运营的稳定性。结果表明,该选址策略可为波浪能电站的合理选址与稳定运行提供科学依据。 展开更多
关键词 波浪能 神经网络 预测 平准化度电成本 SWAN模型 电站选址
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基于嵌套Copula的台风-浪-流三维联合概率建模
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作者 戴靠山 程浩 +1 位作者 张元博 盛超 《东南大学学报(自然科学版)》 北大核心 2026年第1期30-39,共10页
针对台风风速、显著浪高和海流速度相关特性及其联合概率建模研究不足的问题,提出了一种基于阿基米德型嵌套Copula的台风-浪-流三维联合概率建模方法,并验证其在多元极值联合建模中的适用性与准确性。以我国珠三角海域2个典型近海场地为... 针对台风风速、显著浪高和海流速度相关特性及其联合概率建模研究不足的问题,提出了一种基于阿基米德型嵌套Copula的台风-浪-流三维联合概率建模方法,并验证其在多元极值联合建模中的适用性与准确性。以我国珠三角海域2个典型近海场地为例,构建了SWAN+ADCIRC的物理耦合数值模型,获取了1988—2023年极值样本数据。结果表明,台风平均风速、显著浪高与海表面平均流速之间存在较强的相关性,台风平均风速与显著浪高的年最大值线性相关系数最大可达0.9605。台风-浪-流极值依赖结构及其最优嵌套Copula模型具有显著的场地特异性,且环境等值面形状随场地变化明显。环境等值面上不同变量最大值的伴随值具有敏感性,其中海表面平均流速的变异性最强,可达40%。 展开更多
关键词 台风-浪-流 SWAN+ADCIRC 嵌套Copula 联合概率建模 环境等值面
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最美丽的声音——惠威旗舰Swans 2.2的心语
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作者 李政 《中关村》 2003年第8期59-59,共1页
中国之声惠威总裁、加拿大籍华商姚洪波自创业以来,在 Hi—Fi(高保真)扬声器、音响设计行业不觉中已是十余年。和他交谈怎么玩音响,怎样听声音的表现,他用一点点夸张的国语,夹杂着西方人的手势,一脸的痴迷与陶醉。也许正是这种执着才能... 中国之声惠威总裁、加拿大籍华商姚洪波自创业以来,在 Hi—Fi(高保真)扬声器、音响设计行业不觉中已是十余年。和他交谈怎么玩音响,怎样听声音的表现,他用一点点夸张的国语,夹杂着西方人的手势,一脸的痴迷与陶醉。也许正是这种执着才能保证惠威的一个个产品神话,才能解释惠威旗舰 Swans 2. 展开更多
关键词 高音 swans 2.2 带式 音箱 扬声器箱 低音单元
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THE GREAT ANNIHILATOR The unlikely resurgence of Swans
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作者 ANDREW CHIN 《城市漫步(上海版、英文)》 2015年第2期42-43,共2页
"When I decided to invigorate Swans,I had a few colors and palettes in my mind.It's more musical in a traditional sense than in the past,"explains Swans founder and sole constant Martin Gira.Emerging out... "When I decided to invigorate Swans,I had a few colors and palettes in my mind.It's more musical in a traditional sense than in the past,"explains Swans founder and sole constant Martin Gira.Emerging out of the vibrant East Village scene of early 1980s New York that spawned filmmaker Jim Jarmusch and artists like Tony Oursler and John Fekner,Swans is lumped with the so-called“no wave”movement that produced noisy luminaries like Sonic Youth and Glenn Branca responding to the commer-cialization of the city'S original punk scene. 展开更多
关键词 swans SCENE SURGE
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SWAN和WWⅢ海浪模型在南大西洋至几内亚湾的适用性研究
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作者 徐福敏 邢添 彭敬贤 《中国港湾建设》 2025年第7期1-7,共7页
本研究旨在探讨常用海浪模型在南大西洋至几内亚湾海域的适用性及其对海浪要素模拟的特性,对SWAN(Simulating Waves Nearshore)和WWⅢ(WAVEWATCH Ⅲ)模型在南大西洋和几内亚湾海域海浪的模拟结果进行对比分析。2种模型对目标海域进行嵌... 本研究旨在探讨常用海浪模型在南大西洋至几内亚湾海域的适用性及其对海浪要素模拟的特性,对SWAN(Simulating Waves Nearshore)和WWⅢ(WAVEWATCH Ⅲ)模型在南大西洋和几内亚湾海域海浪的模拟结果进行对比分析。2种模型对目标海域进行嵌套模拟和验证,得到南大西洋典型时刻海浪有效波高、平均波周期和峰周期分布。研究表明WWⅢ和SWAN模型均能较好模拟南大西洋至几内亚湾海域海浪。细致对比表明WWⅢ、SWAN分别更适用于南大西洋、几内亚湾海域的海浪模拟;在南大西洋WWⅢ和SWAN模型模拟海浪要素的峰周期差异最大,平均波周期次之,有效波高差异最小;WWⅢ和SWAN模型模拟的差异源于其差分格式和洒水效应GSE(Garden-sprinkler effect)。 展开更多
关键词 SWAN WWⅢ 有效波高 平均波周期 峰周期 南大西洋 几内亚湾
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Reconciling Bergmann's rule throughout the annual cycle in two congeneric large-bodied migratory waterbirds
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作者 Dehai Gu Yanbo Xie +8 位作者 Tetsuo Shimada Hiroyoshi Higuchi Diana Solovyeva Inga Bysykatova-Harmey Yanlei Liu Junjian Zhang Qingshan Zhao Lei Cao Anthony D.Fox 《Avian Research》 2025年第3期433-440,共8页
Bergmann's rule predicts that the larger of two homeotherm species differing only in size would occur at higher latitudes, or in cooler climates than the smaller, because of relative thermoregulatory costs in rela... Bergmann's rule predicts that the larger of two homeotherm species differing only in size would occur at higher latitudes, or in cooler climates than the smaller, because of relative thermoregulatory costs in relation to body mass/surface area ratio. Individual tracking data from two congeneric long-distance migratory northern nesting swan species, Tundra Cygnus columbianus (TS, n = 99) and Whooper Swans C. cygnus (WS, 61–71% larger mass than TS, n = 47) were used to determine their summering and wintering latitudes along similar migration routes and common staging areas along the same flyway. We hypothesised that throughout Arctic and Boreal breeding areas (10℃ in July), summer ambient temperatures mainly exceed the Lower Critical Temperatures (LCT, c. 1℃) for both swan species, so the duration of the snow-free summer period will favour smaller body size at highest latitudes, since this constrains the time available to lay, incubate eggs and raise cygnets to fledging. We hypothesised that in contrast, in winter, both species occur in temperatures near to freezing (−3℃ in January), below their respective LCT, so differential thermoregulation demands would constrain TS to winter south of WS. Tracking of individuals showed for the first time that while smaller TS summered significantly north of WS, WS wintered significantly north of TS, with limited overlap in both seasons. We conclude that differences in relative summer distribution of these two closely related migratory herbivores are not to do with latitude per se but are constrained by the time both species require to raise their young to fledging during the short northern summer, when thermoregulation costs are unlikely limiting. In winter, both swan species occur within a climate envelop at or below their respective LCT and smaller TS occurred consistently south of the range of the tracked WS, as predicted by Bergmann's rule. 展开更多
关键词 Bergmann's rule Breeding latitude Migratory swans Snow-free period Tundra Swan Whooper Swan Win tering latitude
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南大西洋至几内亚湾海浪的精细数值模拟研究
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作者 邢添 徐福敏 郑金海 《海洋工程》 北大核心 2025年第1期158-165,共8页
几内亚湾海域沿岸频繁遭受海浪袭击,研究南大西洋至几内亚湾海域海浪特征及传播特性对西非港口、航道及海岸工程建设意义重大。对SWAN(Simulating Waves Nearshore)和WWIII(WAVEWATCH III)模型在模拟大尺度大西洋和小尺度几内亚湾海域... 几内亚湾海域沿岸频繁遭受海浪袭击,研究南大西洋至几内亚湾海域海浪特征及传播特性对西非港口、航道及海岸工程建设意义重大。对SWAN(Simulating Waves Nearshore)和WWIII(WAVEWATCH III)模型在模拟大尺度大西洋和小尺度几内亚湾海域海浪的行为进行比较,发现WWIII-SWAN双层嵌套模型更适合南大西洋至几内亚湾海域海浪模拟。基于该双层嵌套模型进行2021年7月1日至8月31日自南大西洋至几内亚湾海域的海浪模拟,得到南大西洋典型海浪时刻海浪有效波高分布和峰周期分布。研究表明咆哮西风带高强度海浪沿西南方向传播至包括几内亚湾的西非沿岸,有效波高从10 m以上减少到4 m以内,峰周期自西南向东北方向呈明显分层且逐渐增加。南大西洋至几内亚湾的海浪二维谱能量分布也表明南大西洋海浪自西南向东北传播过程中涌浪占据主导,西非沿岸尤其是几内亚湾大部分时间处于14 s以上长周期涌浪作用中。 展开更多
关键词 南大西洋 几内亚湾 SWAN模型 WWIII模型 WWIII-SWAN双层嵌套模型 海浪 涌浪
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黄东海海域台风浪特征分析
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作者 邱梓欣 程天宇 +2 位作者 高郭平 陈洁 龙逢鑫 《应用海洋学学报》 北大核心 2025年第3期493-504,共12页
紧邻长江口的黄东海海域航线密集,航运繁忙,热带气旋(tropical cyclone,TC)产生的极端海浪显著威胁船舶航行安全。本研究利用1949—2022年影响黄东海海域的TC最佳路径数据集提取风场数据,并驱动SWAN(Simulating WAves Nearshore)海浪模... 紧邻长江口的黄东海海域航线密集,航运繁忙,热带气旋(tropical cyclone,TC)产生的极端海浪显著威胁船舶航行安全。本研究利用1949—2022年影响黄东海海域的TC最佳路径数据集提取风场数据,并驱动SWAN(Simulating WAves Nearshore)海浪模式,获得TC影响下的海浪数据,分析历史台风浪的发生强度、频次和空间分布等特征,探讨不同TC移动速度下的海浪不对称分布特征及危险性海浪的主要可能成因。结果表明,TC影响下,研究海域的海浪强度和出现频率呈现显著的空间差异性,海浪危险等级呈现由东南向西北海域递减的分布特征,极端台风浪的主导波向为SE向。研究海域内,东南部外海海域属于海浪高危险区,30°N以南近海海域的海浪危险等级相对高于30°N以北的近海海域。台风浪呈现明显的不对称分布,右前侧象限的有效波高值更大、波长更长、波周期更长,同时,移动速度介于>3.0~7.0 m/s的中速移动TC引起的海浪场不对称性最明显。 展开更多
关键词 热带气旋 SWAN海浪模式 极端海浪 波要素不对称分布 黄东海海域
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