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1.
J. E. Matthews 《Geo-Marine Letters》1982,2(3-4):215-217
Pulsed ultrasonic techniques for the measurement of sound speed are reliable and well documented. Extension of these techniques
to the measurement of shear wave velocities in marine sediments, generally was unsuccessful. Recently developed shear wave
transducers, based upon piezoelectric benders operated at sonic frequencies, provide significantly improved transducer-sample
mechanical coupling. This improved coupling allows the application of pulsed techniques to the measurement of shear wave velocities
in marine sediments, and the rapid determination of sediment dynamic elastic properties. Two types of bender-based shear wave
transducer and preliminary data are described: 1) a probe configuration for box core samples, and 2) a modification to the
Hamilton Frame Velocimeter for cut samples. 相似文献
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A seabed instrument called Lancelot has been developed to measure pore pressure characteristics within potentially unstable marine sediment deposits, in any water depth. An estimate of the coefficient of consolidation can be obtained from the sediment pore pressure dissipation response that occurs following penetration into the seabed. This data can be used to calculate the coefficient of hydraulic conductivity, which is useful in analyzing the seepage velocity of pore fluids moving within the sediment mass. Pore-water pressures in excess of the normal hydrostatic profile are detected and used in static and dynamic liquefaction analyses, with a view toward understanding the origin of unusual seabed features such as pockmarks, as well as short-term instability caused by wave loading. An example of static liquefaction due to seepage stress is given for sites in and adjacent to the well-known 1929 Grand Banks debris flow, along with an example of incomplete liquefaction caused by dynamic wave loading within Miramichi Inner Harbor, New Brunswick. The adoption of in situ measurement techniques is shown to produce data of a quality not normally obtainable from recovered core samples, due to pressure relief and sampling disturbance effects. 相似文献
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信息技术的快速发展,带动海洋数据快速积累,海洋已经进入大数据时代。海洋大数据即是在当前大数据时代背景下,大数据技术在海洋领域的科学实践,具有大体量(Volume)、多样性(Variety)、快速流转(Velocity)和高价值(Value)的"4V"特征,是在大数据的理论指导和技术支撑下的价值实现,也是实施海洋强国战略、开发海洋资源、拉动海洋经济、维护国家海洋权益的重要基础。本文讨论了海洋大数据的内涵和外延,从数据特征、数据种类的角度对海洋大数据进行了全面的定义;并详细介绍了海洋大数据的应用领域;进一步阐述了海洋大数据平台建设的关键技术问题及其在海洋大数据服务平台实例中的应用;从数据共享、数据管理和数据安全的角度,探讨了海洋大数据面临的挑战和机遇;最后对未来海洋大数据的发展趋势和方向进行了展望。 相似文献
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海洋声场环境研究需要对不同深度的海洋声学环境要素进行同步测量,而感应耦合数据传输技术可实现多个单通道水声测量仪之间的同步采集和记录。文中阐述了感应耦合数据传输技术的特点及其在海洋声学环境同步测量中的应用,介绍了一种利用感应耦合数据传输技术实现数据同步测量的声学浮标系统,详细描述了系统的方案设计、结构组成及感应耦合部分的关键技术。实验水池测试表明,该系统工作稳定可靠,数据同步性好,具有良好的应用前景。 相似文献
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《Oceanic Engineering, IEEE Journal of》1978,3(4):117-119
Ocean measurement systems for the 1980's will require improved capabilities to sample and measure specific ocean parameters. With the increasing costs of ocean operations, these systems must be designed and produced to yield a higher degree of performance and reliability than has been previously available. Also, new capabilities will be required as program emphasis shifts to the continental shelves and margins where the understanding of coastal processes, energy development and production, ocean waste disposal, and improved water quality are of increasing social and economic importance. Some of the requirements for improved marine measurement systems and how they can be achieved are discussed below. 相似文献
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《Ocean & Coastal Management》2006,49(3-4):133-146
The need to rapidly and accurately identify areas for protection and conservation in the marine environment has been highlighted as of critical importance. Managers require timely and cost-effective techniques to obtain biodiversity information at appropriate scales and resolutions aligned with management objectives and stakeholders requirements. In this paper, a two-stage, multi-level data collection framework is presented that will aid managers to focus on what marine biodiversity collection techniques will meet their individual jurisdictional needs.The framework begins with an integrated planning process (objective setting, stakeholder identification, and sensitivity and gap analyses), that leads to a hierarchical approach for selecting biodiversity assessment techniques that will gather required marine biodiversity data. Complexity of scale and resolution increases as one progress's through the hierarchical levels of Stage II. The utility of using a hierarchical framework is that it surmounts the problem that no single technique can quantify all biological attributes necessary for management outcomes. Also, the user enters the framework at a hierarchical level that meets their requirements thus removing the collection of redundant data. Ultimately, the rapid assessment framework is based on the efficient and sufficient assessment of marine biodiversity. 相似文献
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深海极端波浪环境为浮式海洋平台作业时最为关键的海洋动力环境之一。在其作用下,深海浮式平台的运动、气隙以及结构响应等均为近年来的研究热点。然而,在深海环境中,入射波浪环境往往通过X波段雷达进行测量,仅能获得波浪的短时统计值,极大限制了实海域浮动平台动力响应的研究。目前,尚无成熟的方法能够对海洋浮式平台所处海域的入射波时序进行实时测量。针对深远海半潜式平台的波浪时序随船测量问题,结合平台气隙响应与运动响应数据建立基于深层神经网络的波浪非线性解耦模型,准确估计辐射、绕射波浪以及其非线性成分对时序波浪场的影响。研究显示,基于深度神经网络的波浪时序测量技术可以实现从气隙响应到入射波信息的反推,利用该方法计算得到的波浪时序具有较高的精度。 相似文献
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单波束测深仪是现代海洋和内河水下地形测量中使用最为频繁的测量仪器。硬件设备固有特性和水下复杂的特殊环境,易导致单波束测深仪在实际使用中产生各类型的粗差。单波束采集时按照每条测线进行处理,在数据处理上往往存在不同船只、不同测线难以一体化处理的问题。文中针对水深值粗差的特点,设计了单波束数据采集和处理一体化方法,在区域处理单波束数据的基础上,提出一种顾及地形的单波束水深测量数据多测线粗差检测方法,并针对上海周边实测区域对单波束测深数据采集和处理进行全方位的验证,结果表明应用本方法不但提升了数据精度和数据处理可靠性,而且大幅提高了作业效率。 相似文献
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国产深海准实时传输潜标系统设计 总被引：2，自引：2，他引：0
基于海洋环境安全保障、海洋环境预报和海洋科学研究的需要,开展国产深海准实时传输潜标系统的设计,重点进行锚泊系统水动力分析、观测设备工作同步性、准实时通讯系统安全可靠和系统低功耗等整体技术设计;开展轻型感应耦合传输缆制作、大深度感应耦合传输和智能收放通讯等数据实时通讯技术的研究;进行适用于准实时传输潜标系统的多种类国产设备的稳定性和可靠性优化、规模化集成和系统化的应用示范,形成半潜升降式准实时通讯潜标与浮子式准实时通讯潜标各1套。所设计的准实时传输潜标系统集成了1台抗污染CTD、19台感应耦合CTD、8台感应耦合T、4台感应耦合传输的ADCP、2台单点海流计和6台感应耦合数据传输仪,并配有2套声学释放器;潜标系统本体设计含有3个水下流线型浮体、1套通讯浮子、1套准实时卫星通讯装置（半潜式水下绞车或海面浮子）和1套锚泊缆系,可实现深达2 000 mm的剖面温盐深和海流等海洋要素的高频率、多要素、多层次的长期连续观测和数据准实时传输,以便对科学问题解决和海洋环境安全保障等提供及时的数据支撑。 相似文献
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随着全球气候变化加剧,海洋灾害发生的可能性变得越来越大,为了减少海洋灾害造成的损害后果,以及能够在共同面对海洋灾害风险中承担起大国责任,我国需要建立完善的国内海洋防灾救灾体系与灾害防御国际合作机制。通过阐述海洋灾害防御的国际合作模式,分析当前我国参与的国际合作以及其中存在的问题,进而对如何完善我国海洋灾害防御国际合作机制以及构建具有中国特色的海洋灾害风险管理体制进行探讨,以期得到稳定的海洋环境,更好地构建海洋命运共同体与人类命运共同体。 相似文献
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塑料垃圾通过各种途径进入海洋,海洋塑料污染已成为全球性环境问题。本文系统总结了国内外塑料污染的研究历程与现状,发现直接或者间接来源的微塑料在环境中广泛积累,呈全球化分布趋势;重点探讨了我国微塑料的来源、分布以及污染形势和生态影响,发现我国微塑料污染形势严峻,覆盖范围广泛,甚至涉及食品安全领域。塑料的生物降解是受到高度关注的研究领域,本文通过对微塑料的生物降解途径的归纳,总结了塑料降解的过程、生物种类以及相关的降解酶等,以期为海洋微塑料污染的治理提供启示。目前微塑料污染已经引起世界各国的广泛关注,但对海洋环境中微塑料的鉴定以及污染物消除技术等研究极少,迫切需要开展相关研究工作。 相似文献
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Marine mining may disturb the natural marine environment-solids, fluids, or organisms-by removal of materials, addition of foreign material, in-place mixing of existing material, or removal and subsequent replacement of material. Measuring the scope of such disturbances, of course, requires knowing the environmental conditions both before and after mining. Scientists disagree on what constitutes an adequate knowledge of baseline (premining) conditions, and instrumentation and techniques for measuring are not yet satisfactory. A wide range of instrumentation is necessary to measure the many physical, chemical, and biological factors involved. Some measurements must span enough time to encompass natural cyclic changes, but such long-term measurements are hampered by the lack of reliable submersible instrumentation. Inadequacy of measurement capability, for technical or economic reasons or both, is particularly evident regarding dispersion of fine solids and dissolved chemicals in mid-water and benthic layers and, to a lesser extent, in the surface layer of seawater. Especially difficult to measure or predict is the biological effect of mining. The most significant changes may be induced subsequent to the mining operation and may be some distance from it. Secondary effects resulting from these changes may not be obvious, but it is important that they be identified so that predictions can be made for other operations. Planned experiments to improve capability for prediction of effects should reduce the variety of measurement required. Many investigators fail to recognize the value of existing data banks, which consequently receive insufficient institutional financial support. 相似文献
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It is becoming increasingly evident that many users of measured marine data are reluctant to use data acquired by others. This reluctance is based on the feeling that the transfer function characteristics of the instrument system used for the measurements are inadequately defined for the environment in which the measurements were made. It has been estimated that in excess of 50 percent of the marine data presently archived are useless because their quality ("goodness") is unknown. It is far too costly in resources and time on both a national and international basis to continue acquiring data whose questionable credibility severely limits their spectrum of applicability. This paper addresses those key elements that relate to the quantification of data and should be considered when planning and developing a measurement program for the ocean environment. 相似文献
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《Marine Policy》2014
Marine planning presents considerable new challenges and opportunities for those responsible for managing the marine environment. In the UK, the Marine and Coastal Access Act (2009) provides a statutory framework for marine planning and has created a new administration responsible for its implementation. If marine planning is to be effective and achieve its stated goals it will require a pool of trained individuals who will be responsible for or will participate in marine planning. Based on data gathered during the development and delivery of an intensive professional course and a masters level programme, this paper explores the key elements of education and training required by marine planners. These include a knowledge of planning processes and national and international laws and conventions; an understanding of how marine plans can integrate with existing terrestrial and coastal plans and other management requirements; and an understanding of the marine and maritime environment, including the human activities and natural features. It concludes with a discussion of the different roles individuals may play in the planning process and thus their different training needs. 相似文献
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海洋数据的多源性、多态性和多样性以及数据量庞大等特点决定了其不同于其它数据,如何更加合理有效地存储和管理海洋数据,为海洋综合管理信息系统和＂数字海洋＂原型系统建设提供有力的数据支撑,是一个紧迫需要解决的问题。本文对各类海洋资源、海洋环境、海洋经济、海洋管理等数据进行统一的体系规划,构建统一标准的海洋数据体系框架,以实现国家、省（市）等各级海洋数据的有效管理,满足＂数字海洋＂海洋信息基础平台建设需要。 相似文献
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我国海洋监测浮标技术及监测网现状及发展 总被引：5，自引：1，他引：4
海洋资料浮标可以在各种复杂的海洋环境中提供长期、连续、实时、可靠的海洋观测数据,是海洋监测技术中最可靠、最有效、最重要的手段之一。本文概述了海洋资料浮标的分类、主要理论及技术体系;总结了近年来国内海洋资料浮标发展的典型技术突破;介绍了我国目前海洋监测网的构成、应用情况,并对比了我国海洋资料浮标与国际先进国家的技术水平差距,在此基础上,结合我国当前面临的形势及需求,展望了海洋资料浮标及监测网技术的发展趋势。 相似文献
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《Ocean & Coastal Management》2007,50(5-6):329-351
Concerns about marine protected area (MPA) ecological and social effectiveness have led to a growing interest in conducting management evaluations. The variety of stakeholder interests and needs calls into question the typical notion of MPA ‘success’ and suggests that managers need a practical set of techniques to measure performance and evaluate trade-offs. This study explores how success can be analyzed from the compilation of differing stakeholder viewpoints. Qualitative data was collected through interviews with stakeholders to explore the state of an Italian MPA, selection of performance indicators to evaluate the MPA, and whether it can be deemed a success according to those indicators. The results show that stakeholder groups hold significantly different preferences for biological, economic and socio-cultural performance indicators in judging MPA performance. The elicitation of stakeholder preferences here is an important first step in understanding the criteria through which stakeholders view MPA management. 相似文献