Methods in Oceanography最新文献_第9页

New autonomous multiple codend opening/closing control system for a midwater frame trawl 新型自主多码启闭中水框架拖网控制系统

Methods in Oceanography Pub Date : 2012-09-01 DOI: 10.1016/j.mio.2012.09.001

Yoshioki Oozeki , Fuxiang Hu , Chiaki Tomatsu , Hideki Noro , Hiroshi Kubota , Hiroya Sugisaki , Chiyuki Sassa , Akinori Takasuka , Tadashi Tokai

{"title":"New autonomous multiple codend opening/closing control system for a midwater frame trawl","authors":"Yoshioki Oozeki , Fuxiang Hu , Chiaki Tomatsu , Hideki Noro , Hiroshi Kubota , Hiroya Sugisaki , Chiyuki Sassa , Akinori Takasuka , Tadashi Tokai","doi":"10.1016/j.mio.2012.09.001","DOIUrl":"10.1016/j.mio.2012.09.001","url":null,"abstract":"<div><p>A new autonomous multiple codend opening/closing system was constructed to be attached to a midwater trawl net, and the layer discrimination ability of this new system attached to the Matsuda–Oozeki–Hu Trawl (MOHT, mouth area 5 m2) was demonstrated through comparison with the Multiple layer Opening/Closing MOHT (MOC–MOHT), which was equipped with a mouth opening/closing net control system. The new multiple codend opening/closing system was 1.28 m high and 0.75 m wide and has five pyramid-shaped codend nets, with an autonomous control mechanism identical to the MOC–MOHT. Field comparison between the new system and MOC–MOHT demonstrated the accurate layer discrimination ability of the new system and the new codend opening/closing system sufficiently allowed for avoidance of contamination of specimens before the codend frame, after improvement of the main net shape with the cylindrical part before the codend frame. The new autonomous codend opening/closing system attached to MOHT (COC–MOHT) is a reliable multi-layer sampling gear, and the new system itself has the potential of transforming a traditional midwater trawl to an effective multi-layer sampling system, by adding the modification of the net shape before the codend.</p></div>","PeriodicalId":100922,"journal":{"name":"Methods in Oceanography","volume":"3 ","pages":"Pages 14-24"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.mio.2012.09.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73660176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Real time visualization of thermohaline finestructure using Seismic Offset Groups 利用地震偏移组实现热盐精细结构的实时可视化

Methods in Oceanography Pub Date : 2012-09-01 DOI: 10.1016/j.mio.2012.07.003

G.G. Buffett , J.L. Pelegrí , J. de la Puente , R. Carbonell

{"title":"Real time visualization of thermohaline finestructure using Seismic Offset Groups","authors":"G.G. Buffett , J.L. Pelegrí , J. de la Puente , R. Carbonell","doi":"10.1016/j.mio.2012.07.003","DOIUrl":"10.1016/j.mio.2012.07.003","url":null,"abstract":"<div><p>Seismic oceanography is based on the passage of a regularly repeating acoustic impulsive source and an acquisition streamer along the surface of the ocean, and on summing together all signals reflected from temperature and salinity<span> interfaces in the ocean (where there are acoustic impedance contrasts). Due to the inherent redundancy of the method, random noise is attenuated, while signal is preserved; however, if the original signal-to-noise ratio is large enough, one need not use data from the entire streamer to create a 2D profile. A processing scheme is here devised to obtain consecutive images, known as stacks, of the structure of the water column. The scheme, named Seismic Offset Groups (SOG), consists in splitting the data from the whole streamer at a given geographical position into data produced by different streamer subsets. The method is illustrated by partitioning data from a 5-km long streamer into 7 offset groups separated by 3.5 min in time, thereby imaging the same seafloor-referenced location over a period of 21 min. As the streamer passes over a fixed geographical point, motions within the water column are observed. Each stack, created with a subset of the complete streamer, can therefore be considered an image of the water column at a particular time step (animation frame). In this way each image shows a different thermohaline fabric and the animation allows us to visualize internal ocean motions.</span></p></div>","PeriodicalId":100922,"journal":{"name":"Methods in Oceanography","volume":"3 ","pages":"Pages 1-13"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.mio.2012.07.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85564079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Welcome to Methods in Oceanography 欢迎来到海洋学方法

Methods in Oceanography Pub Date : 2012-04-01 DOI: 10.1016/j.mio.2012.07.001

Jules S. Jaffe (Editor in Chief)

引用次数: 0

Steps towards autonomy: From current measurements to underwater vehicles 迈向自主的步骤:从目前的测量到水下航行器

Methods in Oceanography Pub Date : 2012-04-01 DOI: 10.1016/j.mio.2012.05.001

Gwyn Griffiths

引用次数: 6

Assessing biases in computing size spectra of automatically classified zooplankton from imaging systems: A case study with the ZooScan integrated system 从成像系统中评估自动分类浮游动物大小光谱的计算偏差:ZooScan集成系统的案例研究

Methods in Oceanography Pub Date : 2012-04-01 DOI: 10.1016/j.mio.2012.06.001

Pieter Vandromme , Lars Stemmann , Carmen Garcìa-Comas , Léo Berline , Xiaoxia Sun , Gaby Gorsky

{"title":"Assessing biases in computing size spectra of automatically classified zooplankton from imaging systems: A case study with the ZooScan integrated system","authors":"Pieter Vandromme , Lars Stemmann , Carmen Garcìa-Comas , Léo Berline , Xiaoxia Sun , Gaby Gorsky","doi":"10.1016/j.mio.2012.06.001","DOIUrl":"10.1016/j.mio.2012.06.001","url":null,"abstract":"<div><p><span>Body size constrains prey–predator interactions and physiology, therefore plankton size spectra have been appointed as synthetic descriptors of plankton community structure and functioning. Recently developed imaging systems and supervised classification tools provide size measurements of any object </span><em>in situ</em><span> or in net samples and automatically classify them into previously defined categories. But because the nature of objects detected by these imaging systems is diverse, from non-living detritus<span> to organisms of different plankton taxa, and because the steps in the analysis could introduce specific biases, a careful analysis of such plankton size spectra is needed before going deeper into ecological considerations. Using a WP2 net time series, we propose a general framework to analyze and validate zooplankton size spectra collected with nets and analyzed with the ZooScan integrated system that includes supervised classification. Size spectra were controlled, at each step of the procedure, to assess the modification of their shape due to several possible biases: (i) the effect of objects touching each other during the image acquisition, (ii) the error of the automatic classification differing among size classes and (iii) the choice of model to estimate body biovolume.</span></span></p></div>","PeriodicalId":100922,"journal":{"name":"Methods in Oceanography","volume":"1 ","pages":"Pages 3-21"},"PeriodicalIF":0.0,"publicationDate":"2012-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.mio.2012.06.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80435346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 53

30 years of advances in active bioacoustics: A personal perspective 主动生物声学的30年进展:个人观点

Methods in Oceanography Pub Date : 2012-04-01 DOI: 10.1016/j.mio.2012.07.002

Timothy K. Stanton

引用次数: 41