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A comprehensive strength monitoring system used on a fixed jacket platform is presented inthis paper.The long-term monitoring of W-11-4A platform achieved.Structural responses(strain andacceleration)at selected locations,as well as associated environmental parameters,have been obtained.The emphasis of the paper is placed on the system design,and the instrumentation and operationmethodology employed in the monitoring of the structural responses.The performance of the system andthe characteristic results obtained during its 13-month operation are also summarized. 相似文献
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本文总结了针对涠11-4平台一年多时间的应变和加速度监测数据的处理分析工作,详细介绍了所用的数据处理方法,给出了应变数据的统计结果及长期分布规律。通过对应变和加速度信号进行频谱分析,揭示了平台在多种环境条件下的振动特性。 相似文献
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INTRODUCTIONA~q~tityofmudsandSandsbIDughtbyinfluentriverssUSpendin~talseawater.ThemudsandSands,affectedbythetidesandc~ts,areconstantlymoving,tranSportinganddealting,andcancauseseriousinfluencesonharhars,channelsandwaterconservancies,coaStalandOffshae... 相似文献
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Joon-Sang An 《Marine Georesources & Geotechnology》2013,31(4):517-523
ABSTRACTAn evaluation of the stability of subsea tunnels during operation is very important considering the risks involved with subsea tunnels. Although a large volume of monitoring information can be obtained, back analysis has been performed based on the internal displacement. In this study, the efficiency of an estimation of the safety of an operating subsea tunnel has been improved by implementing the back analysis algorithm based on various monitoring information. The differential evolution algorithm was adopted for back analysis of an operating subsea tunnel. The differential evolution algorithm was improved to accommodate the multiple target variables for back analysis, such as the elastic modulus, cohesion, friction angle of the ground, and the time-dependent elastic modulus of concrete lining. In addition, the elastic modulus of the concrete lining and the properties of reinforced ground can be evaluated with the proposed algorithm using a range of monitoring data, such as the internal displacement and stress acting on the lining. In summary, back analysis with a differential evolution algorithm can be used to evaluate the stability of an operating subsea tunnel. 相似文献
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In the course of monitoring and evaluating fish population in the seas, sonar systems have proved a practical and efficient measurement approach. The results obtained, however, from the use of sonar for monitoring fish migration in rivers have been somewhat disappointing-the most troublesome problems being the inability to recognize invalid targets. It has been proposed [1] that a high-resolution Doppler sonar which recognizes a valid target on the basis of its Doppler signature would be a solution to this problem. This paper examines the feasibility of such a target identification scheme. In particular, an examination is made of the nature of returns to be expected from a fish, and of interference sources-principally surface reverberation. From this it is concluded that the Doppler approach is indeed feasible, but that the use of a high-resolution pulsed system capable of separating multiple targets is only possible in a channel width of a few meters. 相似文献
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Kuh Kim Yun Bae Kim Jong Jin Park SungHyun Nam Kyung-Ae Park Kyung-Il Chang 《Ocean Science Journal》2005,40(1):25-44
Long-term, continuous, and real-time ocean monitoring has been undertaken in order to evaluate various oceanographic phenomena
and processes in the East/Japan Sea. Recent technical advances combined with our concerted efforts have allowed us to establish
a real-time monitoring system and to accumulate considerable knowledge on what has been taking place in water properties,
current systems, and circulation in the East Sea. We have obtained information on volume transport across the Korea Strait
through cable voltage measurements and continuous temperature and salinity profile data from ARGO floats placed throughout
entire East Sea since 1997. These ARGO float data have been utilized to estimate deep current, inertial kinetic energy, and
changes in water mass, especially in the northern East Sea. We have also developed the East Sea Real-time Ocean Buoy (ESROB)
in coastal regions and made continual improvements till it has evolved into the most up-to-date and effective monitoring system
as a result of remarkable technical progress in data communication systems. Atmospheric and oceanic measurements by ESROB
have contributed to the recognition of coastal wind variability, current fluctuations, and internal waves near and off the
eastern coast of Korea. Long-term current meter moorings have been in operation since 1996 between Ulleungdo and Dokdo to
monitor the interbasin deep water exchanges between the Japanese and Ulleung Basins. In addition, remotely sensed satellite
data could facilitate the investigation of atmospheric and oceanic surface conditions such as sea surface temperature (SST),
sea surface height, near-surface winds, oceanic color, surface roughness, and so on. These satellite data revealed surface
frontal structures with a fairly good spatial resolution, seasonal cycle of SST, atmospheric wind forcing, geostrophic current
anomalies, and biogeochemical processes associated with physical forcing and processes. Since the East Sea has been recognized
as a natural laboratory for global oceanic changes and a clue to abrupt climate change, we aim at constructing a 4-D continuous
real-time monitoring system, over a decade at least, using the most advanced techniques to understand a variety of oceanic
processes in the East Sea. 相似文献
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声学悬浮泥沙观测系统的研制和应用 总被引:15,自引:4,他引:11
为观测水中悬浮泥沙的浓度剖面、监测水中污染物及研究近岸海区泥沙的迁移和沉积,研制了声学悬浮泥沙观测系统(ASSM).总结了设计时主要技术参数的确定及解决关键技术的方法。应用此系统观测长江口悬浮泥沙,得到典型悬浮泥沙浓度剖面。 相似文献
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垂向二维潮流数值模型及其在长江口北槽的应用 总被引:1,自引:0,他引:1
应用变网格有限元方法,采用任意四边形等参单元,离散横向积分的Navier—Stokes方程,建立河口潮流垂向二维数学模型。应用此模型,对长江口北槽水域两个观测站的潮流水位、流速垂线分布和整个北槽潮流流速纵向分布进行了模拟。潮流水位、流速垂线分布的模拟值分别与观测站的实测值可以较为吻合,证明了本文模型的实用有效。模拟得到的涨急、落急时刻整个北槽潮流流速纵向分布给出了定性的结果。 相似文献
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This paper summarizes the results of perennial combined satellite monitoring of the Black Sea conducted in order to detect sea-surface oil and oil-product pollution, as well as biogenic and anthropogenic surfactant films. A joint analysis of data obtained by various remote sensing techniques has been performed. The large amount of data has resulted in generalizations and reliable statistics on the spatial and temporal variability of different film manifestations in radar images of the sea surface. Regions most severely polluted by petroleum products have been identified. A hypothesis is suggested linking the surface manifestations of certain types of polluting films with natural gas and oil seeps and mud volcanism in the Black Sea. Improvements in the reliability of interpreting satellite data are discussed. 相似文献
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武汉市地下管线外业普查的数据监理 总被引:1,自引:0,他引:1
在进行地下管线普查时,为了保证外业成果数据的正确,并最大限度减少监理工作量,探索和研制了数据监理系统,基本上实现了属性数据监理的自动完成和图形数据的辅助监理。 相似文献
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A. V. Zimin I. E. Kozlov O. A. Atadzhanova B. Chapron 《Izvestiya Atmospheric and Oceanic Physics》2016,52(9):951-960
Widespread short-period internal wave (SPIW) activity in the White Sea has been revealed for the first time based on long-term (2009–2013) monitoring performed using satellite and in situ observations, and the statistical characteristics of these waves have been obtained. Two main regions where short-period waves constantly exist have been identified: the shelf area near the frontal zone at the boundary between the Basin and the Gorlo Strait and the shallow shelf area where the depths are about 30–50 m near Solovetskie Islands. Intense internal waves (IIWs), which are substantially nonlinear and are related to specific phases of a barotropic tide, are regularly observed near frontal zones. The wave height can reach half the sea depth and the wave periods vary from 7 to 18 min. 相似文献
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《Ocean & Coastal Management》1999,42(5):399-418
Seafood tissue monitoring in Santa Monica Bay, CA, for regulatory compliance has provided information about contamination around major wastewater outfalls, but has not been useful in health management. It has not always focused on species caught by sport fishing, or on key sport fishing areas. Separate programs were uncoordinated, using distinct sampling patterns to collect different species. Most importantly, monitoring was not designed to feed information into a formal health management process. The Santa Monica Bay Restoration Project oversaw the development of a regionally coordinated monitoring program. It stressed that monitoring should support risk-based health management decision making by California EPA. This led to fundamental changes in the existing compliance-based monitoring design. We describe these and examine the features of the management system that both allowed for and supported an unusual degree of change in long-standing compliance monitoring programs. 相似文献
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A computer-based system that processes hydrophone and beam noise data from a towed horizontal line array sonar has been developed. The system also produces various displays that can be used to help assess the functionality of the sonar and to identify faults that cause degraded performance. The system-and various statistics used for characterizing or quantifying a given aspect of the sonar's performance are discussed. The results are presented in visual formats to aid in rapid assessment and quantification of the sonar's performance. Examples obtained from the system during recent towed array ambient noise measurement exercises are given to illustrate its utility for real-time performance monitoring and its capability for providing clues to aid in fault localization 相似文献
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The use of lysosomal stability in the mussel, Mytilus galloprovincialis, as a potential biomarker of environmental contamination has been evaluated along the Portuguese coast. To this end, the neutral red retention (NRR) time was measured in mussel haemocytes gathered from nine different locations reflecting different degrees of anthropogenic contamination. Mussels collected in the vicinity of industrial and urban areas showed the lowest lysosomal stability. Additionally, no significant seasonal variability (winter-spring/summer) for NRR time was observed. In order to further support the usefulness of this method as an integrated tool for monitoring marine coastal environments, we compared the levels of xenobiotics in mussel tissues with the obtained NRR values. The results highlighted a consistent pattern, with the lowest lysosomal stability intimately correlated with the higher contaminant concentrations. In summary, this integrated approach further demonstrated that the NRR assay can provide useful and objective indications of the real health status of organisms subjected to different stress agents, being a valid option for environmental monitoring. 相似文献
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A simple underwater video system has been developed for simultaneously imaging sediment suspension and monitoring bed profiles under waves and combined wave-current flows. This consists of a diode-laser-generated light plane and a black-and-white underwater video camera. The laser light illuminates suspended material in section and also provides a bed profile at the bottom. Orthogonal laser/camera pairs are used to obtain both cross-shore and alongshore views. During deployments, the system has been augmented by acoustic backscatter devices for measurement of sediment concentration. As with all video techniques, visibility is a limiting factor, but where turbidity is low to moderate, the results are encouraging. Results on cross-shore and alongshore bed elevation variations and suspension event stales obtained with the video/laser system are presented for two experiments: one at the National Research Council Wave Research Flume in Ottawa, Canada, and the other in the field at Queensland Beach, N.S., Canada, 相似文献
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Ship berthing and mooring monitoring system by using pneumatic-type fenders has been proposed. This system consists of present berth monitoring system including a mooring line load monitoring system, and a fender load monitoring system. The fender loads such as fender deflection and reaction force are calculated by measuring inner air pressure of the pneumatic fenders, which have unique characteristics in performance. Furthermore both loads for the mooring lines and the fenders can be used to estimate moored ship motions simultaneously. Total ship monitoring system at jetty can be achieved and contributes safe ship berthing and mooring. 相似文献
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Time-series InSAR analysis(e.g., permanent scatterers(PSInSAR)) has been proven as an effective technology in monitoring ground deformation over urban areas. However, it is a big challenge to apply this technology in coastal regions due to the lack of man-made targets. An distributed scatterers interferometric synthetic aperture radar(DSInSAR) is developed to solve the problem of insufficient samples and low reliability in monitoring coastal lowland subsidence, by applying a spatially adaptive filter and an eigendecomposition algorithm to estimating the optimal phase of statistically homogeneous distributed scatterers(DSs). Twenty-four scenes of COSMO-Sky Med images acquired between 2013 and 2015 are used to retrieve the land subsidence over the Shangyu District on south coast of the Hangzhou Bay, Zhejiang Province, China. The spatial pattern of the land subsidence obtained by the PS-InSAR and the DSInSAR coincides with each other, but the density of the DSs is three point five times higher than the permanent scatterers(PSs). Validated by precise levelling data over the same period, the DSInSAR method achieves an accuracy of ±5.0 mm/a which is superior to the PS-InSAR with±5.5 mm/a. The land subsidence in the Shangyu District is mainly distributed in the urban areas, industrial towns and land reclamation zones, with a maximum subsidence rate –30.2 mm/a. The analysis of geological data, field investigation and historical reclamation data indicates that human activities and natural compaction of reclamation material are major causes of the detected land subsidence. The results demonstrate that the DSInSAR method has a great potential in monitoring the coastal lowland subsidence and can be used to further investigate subsidence-related environmental issues in coastal regions. 相似文献
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《Ocean & Coastal Management》2007,50(5-6):392-410
Project monitoring is now a standard requirement in natural resource management programs, bringing opportunities for greater accountability, adaptive management and social learning. While considerable effort has gone into designing appropriate monitoring frameworks and indicators for marine and coastal management, there has been less sharing of the mechanics of approaches that maximise collaboration and learning by multiple stakeholders. This paper outlines the project monitoring approach developed in the Pacific Islands International Waters Project (IWP), a project funded by the Global Environment Facility (GEF) involving 14 Pacific Island Countries. We find that a monitoring approach based on indicators to assess supportive processes, behavioural change and human–environmental conditions is useful for monitoring the long- and short-term impacts associated with integrated coastal management programs. Giving project staff the lead in indicator development has supported more strategic project planning and improved the relevance and value of the indicators developed. However, successful implementation of monitoring programs calls for ongoing collaboration, technical support and capacity building amongst key stakeholders. 相似文献