Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600)最新文献_第7页

Identification of underwater vehicle dynamics with neural networks 基于神经网络的水下航行器动力学辨识

Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600) Pub Date : 2004-11-09 DOI: 10.1109/OCEANS.2004.1405750

P. Van de Ven, C. Flanagan, D. Toal

{"title":"Identification of underwater vehicle dynamics with neural networks","authors":"P. Van de Ven, C. Flanagan, D. Toal","doi":"10.1109/OCEANS.2004.1405750","DOIUrl":"https://doi.org/10.1109/OCEANS.2004.1405750","url":null,"abstract":"In this paper modeling of underwater vehicle dynamics using neural networks is investigated. Extensive knowledge is available on the behaviour of underwater vehicles. However, it may prove disadvantageous to use an off line established model of the dynamics due to the varying nature of the underwater environment. Neural networks offer interesting possibilities as they can be used to update the model of the underwater craft during deployment. The literature mainly reports on neural networks used in parallel to the whole system model. The system is thus regarded as a black box and the neural network is required to obtain the desired behaviour without any a priori knowledge. This can result in training problems due to e.g. the inclusion of time delays, necessity of larger (training) data sets and the necessity of larger networks. Rather than using one neural network to approximate a functional representing the whole dynamics, it is proposed to use several neural networks to represent certain model parameters. In this way better use of the model structure, of which detailed information is available, can be made. Some of the parameters, notably the damping parameters, are inherently varying, as they are a function of the velocity. Furthermore, at best only empirical models are available to model the damping. It may thus prove advantageous to approximate the damping using neural networks. The advantages of the proposed 'divide and conquer' approach will be demonstrated","PeriodicalId":390971,"journal":{"name":"Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130404766","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: 9

Wave theory analysis for pulse propagated near sound channel axis in deep water 深水声道轴附近脉冲传播的波动理论分析

Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600) Pub Date : 2004-11-09 DOI: 10.1109/OCEANS.2004.1406475

J. Naoi, H. Saito, H. Fujimori, T. Tsuchiya, T. Kikuchi

{"title":"Wave theory analysis for pulse propagated near sound channel axis in deep water","authors":"J. Naoi, H. Saito, H. Fujimori, T. Tsuchiya, T. Kikuchi","doi":"10.1109/OCEANS.2004.1406475","DOIUrl":"https://doi.org/10.1109/OCEANS.2004.1406475","url":null,"abstract":"The conventional ocean acoustic tomography have analyzed by the ray theory. The rays propagating near the SOFAR (SOund Fixing and Ranging) axis have the slowest wave speed and tend to be over-lapped with each other, so that they become a pulse with large amplitude. But it is difficult to use the last pulse for the final analysis, because it could not be discriminated separately in time domain. In this paper, the last pulse propagating near the axis is analyzed in the time domain by the wave theory. First, the variations of the amplitude of the last pulse are obtained as a function of the propagation range. As a result, it is shown that the last pulse is built by a few waves propagating within the SOFAR channel. Next, the propagation depth range of the waves that contribute to the last pulse is determined by the comparison of the peak amplitude variation obtained by the parabolic equation method and those filtered mode pulse. Lastly, the pattern of the peak amplitude of the last pulse is shown. The vertical distributions may be measured by a vertical hydrophone array. It is thought that these results are greatly useful to the future analysis of the ocean acoustic tomography","PeriodicalId":390971,"journal":{"name":"Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130453404","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

Concept and features of natural gas hydrate pellet carriers 天然气水合物颗粒载体的概念及特点

Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600) Pub Date : 2004-11-09 DOI: 10.1109/OCEANS.2004.1405666

S. Ota, H. Kawano, K. Hirai, M. Kamei

{"title":"Concept and features of natural gas hydrate pellet carriers","authors":"S. Ota, H. Kawano, K. Hirai, M. Kamei","doi":"10.1109/OCEANS.2004.1405666","DOIUrl":"https://doi.org/10.1109/OCEANS.2004.1405666","url":null,"abstract":"Gas hydrate is a material which contains molecules of gases in the structure like cages formed by molecules of water. Natural gas hydrate (NGH) is in equilibrium state at around 193 K under atmospheric pressure and NGH is expected to be stowed and transported at higher temperature due to its special property so-called \"Self-Preservation Effect\". NGH may be used as more economical medium for transporting natural gas than LNG temperature of which is around 110 K, because NGH can be transported under self-preservation condition. Furthermore, it is considered that natural gas hydrate pellet (NGHP) is more promising medium than powdery NGH taking into account filling efficiency in a cargo space and the high self-preservation property of pellets. Mitsui Engineering and Shipbuilding Co., Ltd., the National Maritime Research Institute and Osaka University carried out the collaborative three-year research project on the sea-borne transportation of NGHPs with the financial support of the Japan Railway Construction, Transport and Technology Agency. In this research project, it was experimentally confirmed that Methane Hydrate Pellets (MHPs), which are supposed to have similar properties to those of NGHPs, can be stowed and transported at around 253 K in view of self preservation property. The authors were in charge of conceptual design of \"NGHP carriers\", i.e., specialized bulk carries having gas-tight and insulated cargo spaces, including the identification of safety measures for such ships. The conceptual design was carried out under the philosophy of \"Zero Emission of Natural Gas\" to prevent greenhouse effect due to natural gas. In this paper, we present the concept and some features of NGHP carriers such as necessity of special safety measures, in particular for preventing of explosion, and cargo handling systems, in particular for unloading of NGHPs.","PeriodicalId":390971,"journal":{"name":"Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128024698","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: 4

Basic study on the sign for the visually impaired person in a beach institution 海滨机构视障人士标志的基础研究

Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600) Pub Date : 2004-11-09 DOI: 10.1109/OCEANS.2004.1406390

S. Yukio, K. Takeo, Y. Kazukiyo, S. Kimiyasu

{"title":"Basic study on the sign for the visually impaired person in a beach institution","authors":"S. Yukio, K. Takeo, Y. Kazukiyo, S. Kimiyasu","doi":"10.1109/OCEANS.2004.1406390","DOIUrl":"https://doi.org/10.1109/OCEANS.2004.1406390","url":null,"abstract":"In recent Japan, signs have been introduced, particularly for transport facilities but also in such public spaces as commercial facilities and streets, to improve mobility. However, not many signs have been introduced for the visually disabled and hardly any such signs are provided at beaches. Under this study, knowledge on easily recognisable signs by the visually disabled was obtained and desirable audible signs were investigated to identify easily recognisable signs for such people at beach facilities. A questionnaire survey and an interview survey were conducted to clarify the feelings towards beaches among the visually disabled, the state of sign installation at beach facilities, the assessment results of existing signs and the inconvenience felt by the visually disabled. Additional surveys were also conducted on the degree of understanding of audible signs used in public spaces and on the images of sounds heard at beaches. These surveys found that the recognition of sounds is related to information on the place. At beaches where such place information is scarce, sounds inducing images of a beach were found to be one factor for easily recognisable audible signs","PeriodicalId":390971,"journal":{"name":"Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129001730","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

A design of 2-DOF gripper circuit for deep-sea objects 深海物体二自由度抓取电路设计

Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600) Pub Date : 2004-11-09 DOI: 10.1109/OCEANS.2004.1406327

R. Gad, G. Naik, N. Aralgedad

引用次数: 6

Evaluation of the calibration method using iterative spline interpolation for array shape estimation 评价了用迭代样条插值校准阵列形状估计的方法

Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600) Pub Date : 2004-11-09 DOI: 10.1109/OCEANS.2004.1405468

Hee-Young Park, D. Youn, Chungyong Lee, H. Kang, Ki-Man Kim, Kyeong-Cheol Dho

引用次数: 5

Study on corrosion degradation of wire ropes in sea water 钢丝绳在海水中的腐蚀降解研究

Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600) Pub Date : 2004-11-09 DOI: 10.1109/OCEANS.2004.1406437

T. Moriya, S. Hara, K. Yamakawa, K. Hayasaki, S. Okahata, R. Kanbe

{"title":"Study on corrosion degradation of wire ropes in sea water","authors":"T. Moriya, S. Hara, K. Yamakawa, K. Hayasaki, S. Okahata, R. Kanbe","doi":"10.1109/OCEANS.2004.1406437","DOIUrl":"https://doi.org/10.1109/OCEANS.2004.1406437","url":null,"abstract":"Wire ropes used in marine environment have a great degradation due to corrosion. Accurate inspection methods for corrosion of wire ropes are necessary to ensure their safety. However, technical background data of corrosion is quite few at present, and is not sufficient for wire rope inspection. Collecting the technical data is important to establish and ensure the offshore structure's maintenance technology including wire rope inspection. A laboratory test of wire ropes degradation was carried out with seawater tanks for 5 years since 1994 to 1999. 14 kinds of ropes were used for the experiment. Further, an exposure test in real sea area was also carried out for 11 months in 1997 to acquire degradation data in dry zone above sea level, in ebb zone, and in the seawater zone. Eight kinds of ropes and 3 kinds of wires were used for the exposure test. During the test period, we examined the ropes for several times on the following characteristics. (1) appearance of ropes and strands, (2) cross section of each wire layers, (3) properties of wire: diameter, tensile strength, number of torsion, (4) mass of coating. The changes of characteristic values were approximated in the curve to eliminate fluctuation errors. We calculated the most suitable characteristics values when the experiment was finished and converted into normalized values divided by initial values. Corrosion degradation of some kinds of wire ropes was evaluated with normalized characteristics values, and appearance of their surface and their cross section.","PeriodicalId":390971,"journal":{"name":"Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600)","volume":"PP 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126440322","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: 3

Construction of automatic fishery investigation system using GPS and RFID 基于GPS和RFID的渔业自动调查系统的构建

Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600) Pub Date : 2004-11-09 DOI: 10.1109/OCEANS.2004.1402957

K. Uchida, Y. Miyamoto, T. Kakihara, N. Arai

引用次数: 2

Extreme events in ocean currents through depth in the vicinity of the Iceland-Scotland Ridge 冰岛-苏格兰海脊附近洋流深度的极端事件

Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600) Pub Date : 2004-11-09 DOI: 10.1109/OCEANS.2004.1406517

Cristina Carollo, Ivan Astin

{"title":"Extreme events in ocean currents through depth in the vicinity of the Iceland-Scotland Ridge","authors":"Cristina Carollo, Ivan Astin","doi":"10.1109/OCEANS.2004.1406517","DOIUrl":"https://doi.org/10.1109/OCEANS.2004.1406517","url":null,"abstract":"This study analyses the vertical structure of extreme currents for three sections in the vicinity of the Iceland-Scotland Ridge. The variation of speed and direction with depth of observational currents from the Variability of Exchanges in the Northern Seas (VEINS) project is studied. Currents have been divided into (1) the mean residual flow, (2) tidal current and (3) nontidal surge residuals to assess their relative importance in contributing to extremes. The results show considerable variation in the relative magnitude of the different components as function of both depth and location, which raises a number of fundamental questions concerning the structure of extreme currents and dominance of component effects. It is found that in these locations the amplitude and direction of extreme currents are dominated by the nontidal component in deep water, whereas tidal currents and surges are dominant near the surface and in shallow-water regions. In the section north of the Faroes the mean residual flow is equal to or larger than surge effects in near-surface measurements, where the direction of extreme currents is eastward for all the deployments; away from the sea-surface extremes have a southward-preferred direction. Here, the Faroe Current (FC) and the Iceland-Faroe Front (IFF) probably influence extremes. In the Faroe-Bank Channel current speed shows larger values in bottom measurements where the mean residual flow is dominant; in near-surface measurements the surge is dominant; extremes are found at bearings near 315/spl deg/, particularly below 500 m. In the Faroe-Shetland Channel tide is generally larger than the surge and mean residual flow, particularly in the deployments on the Faroe side of the channel; the preferred direction is southward.","PeriodicalId":390971,"journal":{"name":"Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121505825","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: 1

Cordage Institute rope test methods, standards, and guidelines 绳索协会绳索测试方法、标准和指南

Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600) Pub Date : 2004-11-09 DOI: 10.1109/OCEANS.2004.1406433

J. Flory, E. Huntley, D. Richards, G. Foster

{"title":"Cordage Institute rope test methods, standards, and guidelines","authors":"J. Flory, E. Huntley, D. Richards, G. Foster","doi":"10.1109/OCEANS.2004.1406433","DOIUrl":"https://doi.org/10.1109/OCEANS.2004.1406433","url":null,"abstract":"The Cordage Institute (CI) is an international association of fiber rope manufacturers, users, and suppliers. Its technical committee develops rope test methods, rope performance standards, guidelines and other related documents. This paper discusses some of the CI test methods, standards and guidelines, especially those of interest in marine and industrial use. It compares them with corresponding publications by other standards-setting organizations. The CI test method for fiber rope covers size, weight, and strength tests for conventional ropes and also dry and wet uncycled and cycled strength and change-in length tests. These latter tests are intended for marine ropes and other ropes for engineered systems. The CI yarn abrasion test demonstrates the durability of yarns in ropes which experience cyclic tension fatigue and bend fatigue. It is referenced in standards published by OCIMF, API and ABS for ropes used in marine mooring systems. CI publishes performance standards for twelve common types of synthetic fiber rope as well as for high-performance and specialty rope types. It publishes reference tables giving properties of conventional and high-modulus fiber yarns. It recently published a comprehensive Fiber Rope Inspection Guide","PeriodicalId":390971,"journal":{"name":"Oceans '04 MTS/IEEE Techno-Ocean '04 (IEEE Cat. No.04CH37600)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122541430","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