中国会展最新文献_第8页

On the role of modeling in passive synthetic aperture processing 论建模在被动合成孔径处理中的作用

中国会展 Pub Date : 2000-09-11 DOI: 10.1109/OCEANS.2000.881227

E. Sullivan

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引用次数: 5

A possible relationship between waveguide properties and bandwidth utilization in humpback whales 座头鲸波导特性与带宽利用之间的可能关系

中国会展 Pub Date : 2000-09-11 DOI: 10.1109/OCEANS.2000.882192

Eduardo Mercado, Z. Michalopoulou, L. N. Frazer

引用次数: 7

DREDGEMAP: a GIS-based dredging model system DREDGEMAP:一个基于gis的疏浚模型系统

中国会展 Pub Date : 2000-09-11 DOI: 10.1109/OCEANS.2000.882221

E. Howlett, C. Galagan, J. Clausner, B. Johnson

引用次数: 1

A new sampler for monitoring fluid and chemical fluxes in hydrologically active submarine environments 一种在水文活跃的海底环境中监测流体和化学通量的新型采样器

中国会展 Pub Date : 2000-09-11 DOI: 10.1109/OCEANS.2000.881242

M. Kastner, H. Jannasch, Y. Weinstein, J. Martin

引用次数: 5

AUV positioning using bathymetry matching 利用测深匹配进行水下航行器定位

中国会展 Pub Date : 2000-09-11 DOI: 10.1109/OCEANS.2000.882248

R. Beckman, A. Martinez, B. Bourgeois

{"title":"AUV positioning using bathymetry matching","authors":"R. Beckman, A. Martinez, B. Bourgeois","doi":"10.1109/OCEANS.2000.882248","DOIUrl":"https://doi.org/10.1109/OCEANS.2000.882248","url":null,"abstract":"A research concern in AUV positioning is the constraint of INS error growth; approaches to this include surfacing for GPS fixes, terrain matching methods and acoustic transponder systems. The paper presents a positioning technique for AUV's that exploits existing bathymetric data in an operation area. Unlike many terrain matching approaches, which do positioning using distinct ocean bottom features, this method generates a position estimate by comparing the in-situ measured depth at the position of the AUV with available bathymetry data in the immediate area. This builds on contemporary AUV INS/VL navigation systems by incorporating a maximum likelihood estimate of position. Particular emphasis is placed on the design of the maximum likelihood estimator module which produces point-wise position estimates and typically contains a large error component with many outliers. This estimate is merged with the output of the AUV's INS/VL system which constrains the INS drift. Further position accuracy and faster convergence to the correct position can be achieved by incorporating a single slant range measurement from the AUV to a fixed location. The slant range is used as external constraint on both the INS and the MLE. The paper describes the implementation of this approach and the results of simulation studies.","PeriodicalId":68534,"journal":{"name":"中国会展","volume":"1 1","pages":"2123-2127 vol.3"},"PeriodicalIF":0.0,"publicationDate":"2000-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79921159","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: 14

An evolution of an information technology architecture for oceanography 海洋学信息技术体系结构的演变

中国会展 Pub Date : 2000-09-11 DOI: 10.1109/OCEANS.2000.881746

J. Lever, L. Bernard, I. Moore, W.J. Moseley, R. J. Starek

引用次数: 0

Subsurface classification of high-resolution seismic data with multivariate statistical techniques: case study from the Strait of Georgia 基于多元统计技术的高分辨率地震资料地下分类:以乔治亚海峡为例

中国会展 Pub Date : 2000-09-11 DOI: 10.1109/OCEANS.2000.882182

S. Bloomer, D. Mosher, W. Collins, J. M. Preston, A. Rosenberger

{"title":"Subsurface classification of high-resolution seismic data with multivariate statistical techniques: case study from the Strait of Georgia","authors":"S. Bloomer, D. Mosher, W. Collins, J. M. Preston, A. Rosenberger","doi":"10.1109/OCEANS.2000.882182","DOIUrl":"https://doi.org/10.1109/OCEANS.2000.882182","url":null,"abstract":"The use of multivariate statistics on the features of echo sounder returns has empirically and repeatedly been shown to be successful in classifying bottom types. The features are derived from the shape and the spectral character of the first echo. They, and other aspects of the data processing, have been optimized for sounder frequencies for which surface scattering dominates over that from volume inhomogeneities. Many engineering applications, such as dredging, the laying of submarine pipelines and cables, the siting of drill and production platforms, and the building of bridges and dams require knowledge of the subsurface. With the development of high-resolution digital seismic systems such as chirp sonars and the IKB SEISTEC/sup TM/ system in the last decade, mapping of the subsurface in shallow water has become cost-effective. This paper describes results from applying these statistical techniques to normal-incidence high-resolution seismic reflection data in which the surface scattering is far less significant, with the hope that these methods will be an adjunct to, and perhaps eventual replacement for, manual expert classification decisions.","PeriodicalId":68534,"journal":{"name":"中国会展","volume":"30 1","pages":"1677-1683 vol.3"},"PeriodicalIF":0.0,"publicationDate":"2000-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83583149","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

Marine seafloor sediment profiling and classification in the Arctic Ocean 北冰洋海底沉积物剖面和分类

中国会展 Pub Date : 2000-09-11 DOI: 10.1109/OCEANS.2000.882215

T. Opishinski, D. Caulfield

{"title":"Marine seafloor sediment profiling and classification in the Arctic Ocean","authors":"T. Opishinski, D. Caulfield","doi":"10.1109/OCEANS.2000.882215","DOIUrl":"https://doi.org/10.1109/OCEANS.2000.882215","url":null,"abstract":"Ocean Data Equipment Corporation redesigned their FM Chirp sub-bottom profiler, the Bathy 2000P, for operation aboard a US Navy Sturgeon-class nuclear powered submarine. Normally operated from a surface vessel, the Bathy 2000P was customized to meet specifications provided by scientists from Lamont-Doherty Earth Observatory of Columbia University for use as an Arctic research tool. An overview of the system design criteria is given that details the difficulties posed by operation aboard a submarine surveying in the Arctic and how the system was tailored to meet the scientific objectives for operation in a complex environment. Successful operation of the Bathy 2000P during two annual Submarine Science Ice Expeditions (SCICEX) has provided seafloor and sediment sonar data previously unavailable to the scientific community. High-resolution acoustic images of the Arctic marine sub-bottom and topographic contours are presented and corroborate the use of a submarine as a platform for acoustic acquisition of geophysical data. Additional processed data, generated using a unique suite of algorithms to derive spectral and absorption loss characteristics are presented. These techniques illustrate the possibility of extending our geophysical knowledge through sediment characterization of the Arctic basin without the need for extended physical sampling.","PeriodicalId":68534,"journal":{"name":"中国会展","volume":"35 1","pages":"1901-1906 vol.3"},"PeriodicalIF":0.0,"publicationDate":"2000-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91237777","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: 0

Bonded flexible pipe 粘接挠性管

中国会展 Pub Date : 2000-09-11 DOI: 10.1109/OCEANS.2000.881801

V. Northcutt

{"title":"Bonded flexible pipe","authors":"V. Northcutt","doi":"10.1109/OCEANS.2000.881801","DOIUrl":"https://doi.org/10.1109/OCEANS.2000.881801","url":null,"abstract":"This paper presents an overview of bonded flexible pipe improvements primarily driven by environmental safety as applied to offshore development using mobile production systems. Bonded pipe is a flexible pipe where the steel reinforcement is integrated and bonded to a vulcanized elastomeric material. Textile material is included in the structure to obtain additional structural reinforcement or to separate elastomeric layers. The applications addressed by this paper are sweet service production, including well stream product and stabilized crude export. Production products include gas, water and injection chemicals. The bonded flexible pipe is used as static flowline and dynamic risers and loading and discharge marine hose. A new application for bonded flexible pipe that did not require much in the way of new technological development is offshore mobile production systems. Until 1989 there had been very little new development in bonded flexible pipe but with the introduction of offshore mobile production systems (MOPS) this changed. The mobile offshore production systems considered is the MOPS used on the Gombe Beta Field, Gabon, West Africa and the MOPS used on the Tchatamba Field, also offshore Gabon, West Africa. The MOPS is accepted in the oil industry as a means to collect reservoir data through extended well tests, to provide early cash flow from major fields and to produce marginal fields. The author focuses on bonded flexible risers, bonded flexible pipelines and bonded floating export hose that comprise the three critical bonded flexible pipe applications. All three are used to convey crude between the production unit, storage tanker and export tanker.","PeriodicalId":68534,"journal":{"name":"中国会展","volume":"354 1","pages":"1407-1412 vol.2"},"PeriodicalIF":0.0,"publicationDate":"2000-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77834434","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

Marine cathodic protection-historical trends and recent accomplishments 海洋阴极保护的历史趋势和最新成就

中国会展 Pub Date : 2000-09-11 DOI: 10.1109/OCEANS.2000.882199

W. Hartt

引用次数: 1