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荷兰船用设备商协会(HME)成员公司介绍Alewijnse Marine Systems
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《船舶工程》 CSCD 北大核心 2007年第2期37-37,共1页
Alewijnse Marine Systems是一家拥有悠久传统的航运技术集团公司。400多个技能娴熟的职工保证了我们每年100多艘船的起帆。作为充填线系统的综合者,我们在全球范围内提供技术服务、革新的电气工程和ICT解决方案。在明确了解客户需求... Alewijnse Marine Systems是一家拥有悠久传统的航运技术集团公司。400多个技能娴熟的职工保证了我们每年100多艘船的起帆。作为充填线系统的综合者,我们在全球范围内提供技术服务、革新的电气工程和ICT解决方案。在明确了解客户需求、船级社规范和技术可能性的基础上,我们为每一项工程提供最好的解决方案:我们掌握着专业知识! 展开更多
关键词 systemS marine 公司介绍 船用 设备商 协会 荷兰 航运技术
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Vibration Control of A Flexible Marine Riser System Subject to Input Dead Zone and Extraneous Disturbances 被引量:1
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作者 ZHOU Li WANG Guo-rong WAN Min 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期271-284,共14页
An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control... An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control precision.Specifically,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each subsystem.Three direction interference observers are designed to track the timevarying boundary disturbance.On this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead zone.In addition,the stability of the closed-loop system is proven by Lyapunov stability theory.All the system states are bounded,and the vibration offset of the riser converges to a small area of the initial position.Finally,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller. 展开更多
关键词 adaptive backstepping control disturbance observer flexible marine riser input dead zone vibration control
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Control of Earth system evolution on the formation and enrichment of marine ultra-deep petroleum in China
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作者 ZHANG Shuichang WANG Huajian +3 位作者 SU Jin WANG Xiaomei HE Kun LIU Yuke 《Petroleum Exploration and Development》 SCIE 2024年第4期870-885,共16页
Taking the Paleozoic of the Sichuan and Tarim basins in China as example,the controlling effects of the Earth system evolution and multi-spherical interactions on the formation and enrichment of marine ultra-deep petr... Taking the Paleozoic of the Sichuan and Tarim basins in China as example,the controlling effects of the Earth system evolution and multi-spherical interactions on the formation and enrichment of marine ultra-deep petroleum in China have been elaborated.By discussing the development of“source-reservoir-seal”controlled by the breakup and assembly of supercontinents and regional tectonic movements,and the mechanisms of petroleum generation and accumulation controlled by temperature-pressure system and fault conduit system,Both the South China and Tarim blocks passed through the intertropical convergence zone(ITCZ)of the low-latitude Hadley Cell twice during their drifts,and formed hydrocarbon source rocks with high quality.It is proposed that deep tectonic activities and surface climate evolution jointly controlled the types and stratigraphic positions of ultra-deep hydrocarbon source rocks,reservoirs,and seals in the Sichuan and Tarim basins,forming multiple petroleum systems in the Ediacaran-Cambrian,Cambrian-Ordovician,Cambrian-Permian and Permian-Triassic strata.The matching degree of source-reservoir-seal,the type of organic matter in source rocks,the deep thermal regime of basin,and the burial-uplift process across tectonic periods collectively control the entire process from the generation to the accumulation of oil and gas.Three types of oil and gas enrichment models are formed,including near-source accumulation in platform marginal zones,distant-source accumulation in high-energy beaches through faults,and three-dimensional accumulation in strike-slip fault zones,which ultimately result in the multi-layered natural gas enrichment in ultra-deep layers of the Sichuan Basin and co-enrichment of oil and gas in the ultra-deep layers of the Tarim Basin. 展开更多
关键词 evolution of Earth system multi-spherical interaction Paleozoic marine ultra-deep petroleum Tarim Basin Sichuan Basin
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Temporal variations of food web in a marine bay ecosystem based on LIM-MCMC model
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作者 Pengcheng Li Hu Zhang +4 位作者 Chongliang Zhang Binduo Xu Yupeng Ji Yiping Ren Ying Xue 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第8期79-88,共10页
Climate change has led to significant fluctuations in marine ecosystems,including alterations in the structure and function of food webs and ecosystem status.Coastal ecosystems are critical to the functioning of the e... Climate change has led to significant fluctuations in marine ecosystems,including alterations in the structure and function of food webs and ecosystem status.Coastal ecosystems are critical to the functioning of the earth’s lifesupporting systems.However,temporal variations in most of these ecosystems have remained unclear so far.In this study,we employed a linear inverse model with Markov Chain Monte Carlo(LIM-MCMC)combined with ecological network analysis to reveal the temporal variations of the food web in Haizhou Bay of China.Food webs were constructed based on diet composition data in this ecosystem during the year of 2011 and 2018.Results indicated that there were obvious temporal variations in the composition of food webs in autumn of 2011 and 2018.The number of prey and predators for most species in food web decreased in 2018 compared with 2011,especially for Trichiurus lepturus,zooplankton,Amblychaeturichthys hexanema,and Loligo sp.Ecological network analysis showed that the complexity of food web structure could be reflected by comprehensive analysis of compartmentalized indicators.Haizhou Bay ecosystem was more mature and stable in 2011,while the ecosystem’s self-sustainability and recovery from disturbances were accelerated from 2011 to 2018.These findings contribute to our understanding of the dynamics of marine ecosystems and highlight the importance of comprehensive analysis of marine food webs.This work provides a framework for assessing and comparing temporal variations in marine ecosystems,which provides essential information and scientific guidance for the Ecosystem-based Fisheries Management. 展开更多
关键词 LIM-MCMC ecological network analysis marine ecosystem food web
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A Pre-Selection-Based Ant Colony System for Integrated Resources Scheduling Problem at Marine Container Terminal
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作者 Rong Wang Xinxin Xu +2 位作者 Zijia Wang Fei Ji Nankun Mu 《Computers, Materials & Continua》 SCIE EI 2024年第8期2363-2385,共23页
Marine container terminal(MCT)plays a key role in the marine intelligent transportation system and international logistics system.However,the efficiency of resource scheduling significantly influences the operation pe... Marine container terminal(MCT)plays a key role in the marine intelligent transportation system and international logistics system.However,the efficiency of resource scheduling significantly influences the operation performance of MCT.To solve the practical resource scheduling problem(RSP)in MCT efficiently,this paper has contributions to both the problem model and the algorithm design.Firstly,in the problem model,different from most of the existing studies that only consider scheduling part of the resources in MCT,we propose a unified mathematical model for formulating an integrated RSP.The new integrated RSP model allocates and schedules multiple MCT resources simultaneously by taking the total cost minimization as the objective.Secondly,in the algorithm design,a pre-selection-based ant colony system(PACS)approach is proposed based on graphic structure solution representation and a pre-selection strategy.On the one hand,as the RSP can be formulated as the shortest path problem on the directed complete graph,the graphic structure is proposed to represent the solution encoding to consider multiple constraints and multiple factors of the RSP,which effectively avoids the generation of infeasible solutions.On the other hand,the pre-selection strategy aims to reduce the computational burden of PACS and to fast obtain a higher-quality solution.To evaluate the performance of the proposed novel PACS in solving the new integrated RSP model,a set of test cases with different sizes is conducted.Experimental results and comparisons show the effectiveness and efficiency of the PACS algorithm,which can significantly outperform other state-of-the-art algorithms. 展开更多
关键词 Resource scheduling problem(RSP) ant colony system(ACS) marine container terminal(MCT) pre-selection strategy
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An emergency decision support system for the marine pollution 被引量:1
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作者 宋军 郭俊如 +7 位作者 牟林 刘玉龙 李琰 袁泽轶 李欢 高佳 王国松 姚志刚 《Marine Science Bulletin》 CAS 2015年第2期56-67,共12页
The paper introduces the research progress in an emergency decision support system for marine pollution (EDSS) in China seas and elaborates on the possible role of the Neutron Activation Analysis (NAA) method ther... The paper introduces the research progress in an emergency decision support system for marine pollution (EDSS) in China seas and elaborates on the possible role of the Neutron Activation Analysis (NAA) method therein. To deal with the increasingly grave situation of offshore pollution, the EDSS for China seas has been researching and developing. Based on the prediction and analysis of the ocean three-dimensional current field, this system makes an inference on the possible path of diffusion and influencing area of marine pollutants and possible location of pollution source, and in combination with the environmentally sensitive information related to the technical integration of GIS, it puts forward the decision, making support for minimizing the hazard caused by pollutants. This system has been operationalized and running for many years on the Bohai and Huanghai seas' Marine Pollutants Prediction and Early-Warning, and it has achieved successful experience for many times in the emergencies of China's coastal pollution accidents. At present, the environmental guarantee system directed against heavy metals and radioactive pollutants is in the experimental stage. As the NAA method is especially applicable to the detection of part of heavy metals and radioactive substances, it is of very important practical value for the new system to realize the monitoring, prediction and early-warning of ocean heavy metals and radioactive pollutants. 展开更多
关键词 marine pollution Neutron Activation Analysis ocean modeling
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Research on the Testing Methods of Instrumental System in the Marine Magnetic Survey 被引量:1
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作者 边刚 刘雁春 +2 位作者 于波 肖付民 卞光浪 《Marine Science Bulletin》 CAS 2007年第2期1-11,共11页
Testing methods of instrumental system in the marine magnetic survey have been studied in this paper, and the feasibility of each method has been testified by the observed data. The conclusion shows that the method br... Testing methods of instrumental system in the marine magnetic survey have been studied in this paper, and the feasibility of each method has been testified by the observed data. The conclusion shows that the method brought out can effectively eliminate the systematic error caused by the instrumental system, and greatly improve the surveying precision and the reliability of the survey results. 展开更多
关键词 marine magnetic survey instrumental system testing method
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Spatio-temporal Evolution of Marine Fishery Industry Ecosystem Vulnerability in the Bohai Rim Region 被引量:5
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作者 LI Bo JIN Xiaoming 《Chinese Geographical Science》 SCIE CSCD 2019年第6期1052-1064,共13页
The building of the ocean power strategy and the implementation of the blue agriculture plan urgently need to strengthen the sustainable development of marine fishery.Taking vulnerability as the starting point, this p... The building of the ocean power strategy and the implementation of the blue agriculture plan urgently need to strengthen the sustainable development of marine fishery.Taking vulnerability as the starting point, this paper constructs the vulnerability index system of marine fishery industry ecosystem from the aspects of sensitivity and response capacity, and combines the entropy method with the Topsis to comprehensively analyze the spatio-temporal evolution characteristics of vulnerability of marine fishery industry ecosystem in the Bohai Rim Region from 2001 to 2015.The results show that: 1) In the time dimension, from 2001 to 2015, the vulnerability of the marine fishery industry ecosystem in the Bohai Rim Region shows a fluctuant and degressive trend;2) In the spatial dimension, the spatial distribution of the marine fishery industry ecosystem vulnerability in the Bohai Rim Region presents the gradient characteristics which shows high vulnerability in the east and low vulnerability in the west.According to the evolution track of the system’s vulnerability level, the vulnerability of the marine fishery industry ecosystem is divided into ‘declining’ and ‘stable’ types of evolutionary structures;3) The development of marine fishery in the Bohai Rim Region needs to be derived from the marine fishery’s ecological environment and the industrial development mode and structure, which can improve the marine environment remediation efforts, optimize the marine fishery industry structure, vigorously focus on pelagic fishery, and enhance the introduction of marine fishery’s science and technology talents, etc.Then, the marine fishery’s development in the Bohai Rim Region will be moving in the green, circular and sustainable direction. 展开更多
关键词 marine FISHERY marine INDUSTRY ecosystem vulnerability SPATIO-TEMPORAL EVOLUTION Bohai RIM Region
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Basic theory and key technologies for marine geographic information system 被引量:8
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作者 SU Fenzhen YANG Xiaomei +2 位作者 XU Jun ZHANG Tianyu LUO Jiancheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第2期80-86,共7页
Marine geographic information system (MGIS) has great ability to deal with the spatio-temporal problems and has potential superiority when it is applied to oceanography. Using the feature extraction of oceanic pheno... Marine geographic information system (MGIS) has great ability to deal with the spatio-temporal problems and has potential superiority when it is applied to oceanography. Using the feature extraction of oceanic phenomena as a case study, the functions of the MGIS are analyzed, and thus the position of MGIS in the oceanography is defined. Comparing the requirement of MGIS with that of the traditional GIS which has been developed in the terrestrial applications in the past four decades, the frame for the functions of MGIS is constructed. According to the established MGIS, some key technologies are discussed in detail with emphasis on the specialities which can distinguish the MGIS from the traditional GIS. 展开更多
关键词 marine geographic information system remote sensing function structure data mining
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Studies on the role of marine bacteria in the upwelling ecosystem——Ⅰ.Bacterial biomass in the upwelling regions 被引量:14
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作者 Zheng Tianling, Cai Lizhe and Jiang Xianquan Environmental Science Research Center, Xiamen University, Xiamen 361005, China Department of Oceanography, Xiamen University, Xiamen 361005, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1993年第2期261-272,共12页
-Six cruises were carried out off the south bank of Fujian - Taiwan during the period of December 21, 1987 to November 15, 1988 to estimate the contribution of bacterial biomass carbon (BBC) to the totai particulate o... -Six cruises were carried out off the south bank of Fujian - Taiwan during the period of December 21, 1987 to November 15, 1988 to estimate the contribution of bacterial biomass carbon (BBC) to the totai particulate organic pools using epifluorescent microscopic technique. The results show that the standing crop of bacteria fluctuated from 0. 95 to 66. 60 mg /m3 (dry weight). Upwelling phenomena appeared in the region around Nanpeng Island in summer while in the region of Waixie in all seasons. The average value of BBC was 27. 60(±6. 08)mg/m3and 21. 32 (±2. 34) mg/m3 respectively. The seasonal and spatial distribution is discussed in relation to environmental factors as well as upwelling phenomena. The role of bacteria in the flow of material and energy in the upwelling ecosystem is emphasized. 展开更多
关键词 marine bacteria upwelling ecosystem
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Complete Modeling for Systems of a Marine Diesel Engine 被引量:6
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作者 Hassan Moussa Nahim Rafic Younes +1 位作者 Chadi Nohra Mustapha Ouladsine 《Journal of Marine Science and Application》 CSCD 2015年第1期93-104,共12页
This paper presents a simulator model of a marine diesel engine based on physical, semi-physical, mathematical and thermodynamic equations, which allows fast predictive simulations The whole engine system is divided i... This paper presents a simulator model of a marine diesel engine based on physical, semi-physical, mathematical and thermodynamic equations, which allows fast predictive simulations The whole engine system is divided into several functional blocks: cooling, lubrication, air, injection, combustion and emissions. The sub-models and dynamic characteristics of individual blocks are established according to engine working principles equations and experimental data collected from a marine diesel engine test bench for SIMB Company under the reference 6M26SRP1. The overall engine system dynamics is expressed as a set of simultaneous algebraic and differential equations using sub-blocks and S-Functions of Matlab/Simulink. The simulation of this model, implemented on Matlab/Simulink has been validated and can be used to obtain engine performance, pressure, temperature, efficiency, heat release, crank angle, fuel rate, emissions at different sub-blocks. The simulator will be used, in future work, to study the engine performance in faulty conditions, and can be used to assist marine engineers in fault diagnosis and estimation (FDI) as well as designers to predict the behavior of the cooling system, lubrication system, injection system, combustion, emissions, in order to optimize the dimensions of different components. This program is a platform for fault simulator, to investigate the impact on sub-blocks engine's output of changing values for faults parameters such as: faulty fuel injector, leaky cylinder, worn fuel pump, broken piston rings, a dirty turbocharger, dirty air filter, dirty air cooler, air leakage, water leakage, oil leakage and contamination, fouling of heat exchanger, pumps wear, failure of injectors (and many others). 展开更多
关键词 marine diesel engine engine system cooling system lubrication system air system injection system combustion system emissions system fault diagnosis and estimation (FDI)
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River-gulf system--the major location of marine source rock formation 被引量:7
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作者 Deng Yunhua 《Petroleum Science》 SCIE CAS CSCD 2012年第3期281-289,共9页
Petroleum was generated from sedimentary rocks. The world's oldest oil source rock so far was found in Proterozoic rocks. Since then, 73% to 81% of the earth's surface has been covered with sedimentary rocks. Howeve... Petroleum was generated from sedimentary rocks. The world's oldest oil source rock so far was found in Proterozoic rocks. Since then, 73% to 81% of the earth's surface has been covered with sedimentary rocks. However, only quite a limited area is rich in oil and gas. It is found that source rocks have controlled oil and gas distribution, and they are mainly formed in two systems: (1) river-lake systems and (2) river-gulf systems. Phytoplankton is an important source of kerogen, the blooming of which is strongly dependent on nutrients. Rivers are the major nutrient provider for basins. Rivers around lakes and an undercompensation (where the sedimentation rate is less than the rate of basin subsidence) environment provide favorable conditions for phytoplankton blooming in lakes. Gulfs are usually located at the estuary of big rivers, characterized by restricted current circulation and exchange with the open sea, which benefit maintaining the nutrient density, phytoplankton levels and organic matter preservation. The river-gulf system is the most favorable place for marine source rock development. Most of the world famous marine petroleum-rich provinces are developed from river-gulf systems in geological history, such as the Persian Gulf Basin, Siberian Basin, Caspian Basin, North Sea, Sirte Basin, Nigerian Basin, Kwanza Basin, Gulf of Mexico, Maracaibo Basin and the Eastern Venezuelan Basin. 展开更多
关键词 Nutrient supply river-gulf system marine source rock oil-bearing basin
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Methods of Studying Petroleum Systems in Residual Basins-A Case Study of Mesozoic and Palaeozoic MarineBasins in Southern China 被引量:5
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作者 ZHAO Zongju, ZHU Yan, YANG Shufeng, WANG Genghai,XU Yunjun, FENG Jialiang and DENG Hongying Department of Geoscience, Zhejiang University, Hangzhou 310027, Zhejiang Hangzhou Institute of Petroleum Geology, Hangzhou 310023, Zhejiang Zhou Jian Fei Zhenbi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2002年第2期205-220,共16页
Through an integrated study of Mesozoic and Palaeozoic petroleum geology insouthern China and a summing-up of the results of exploration, the authors tentatively put forward aset of methods of studying petroleum syste... Through an integrated study of Mesozoic and Palaeozoic petroleum geology insouthern China and a summing-up of the results of exploration, the authors tentatively put forward aset of methods of studying petroleum systems in modified residual basins or superposed basins. Itscore idea is to put emphasis on the study of the dynamic evolution of petroleum systems. Thetempo-spatial evolution, hydrocarbon-generating processes and hydrocarbon-generating intensities andamounts of resources in different geological stages of chief source rocks are mainly deducedbackward by 3-D basin modelling. The regularities of formation and destruction of oil and gasaccumulations are summarized by analyzing the fossil and existing oil and gas accumulations, thedirection of migration is studied by palaeo-structural analysis, and the dynamic evolution ofPalaeozoic and Mesozoic petroleum systems in southern China is studied according to stages of majortectonic movements. The authors suggest that the realistic exploration targets of Palaeozoic andMesozoic petroleum systems in southern China are secondary and hydrocarbon-regeneration petroleumsystems, while the existing primary petroleum systems are rare. They propose that the favourableareas for exploration of Palaeozoic and Mesozoic petroleum systems in southern China are the frontarea of the Daba Mountains and the steep anticlinal zone on the western side of the Shizhusynclinorium in northeastern Sichuan, the Funin-Yancheng-Hai'an-Xinghua-Baoying area in the northernJiangsu basin, the Qianjiang-Xiantao-Paizhou-Chacan 1 well area in the southern part of the Chenhuarea of the Jianghan basin, the South Poyang basin in Jiangxi and the North subbasin of the Chuxiongbasin. This view has been supported by the discovery of the Zhujiadun gas field in the Yanchengsubbasin of the northern Jiangsu basin and the Kaixiantaixi oil-bearing structure in the southernpart of the Chenhu area of the Jianghan basin. 展开更多
关键词 residual basin superposed basin petroleum system marine basin southern China
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Development of in-situ Marine Sediment Geo-Acoustic Measurement System with Real-Time and Multi Frequencies (the Second Generation) 被引量:7
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作者 陶春辉 邓显明 +6 位作者 李红星 周建平 金肖兵 傅顺声 Wlkens R. H 顾春华 何拥华 《China Ocean Engineering》 SCIE EI 2009年第4期769-778,共10页
Compared with the laboratory acoustic measurement of sediment samples, the in-situ acoustic measurement in marine sediment is considered more accurate and rehable, because it covers all of the surrounding environment ... Compared with the laboratory acoustic measurement of sediment samples, the in-situ acoustic measurement in marine sediment is considered more accurate and rehable, because it covers all of the surrounding environment factors and avoids the disturbance during the course of sampling and transporting of sediment samples. A new multi-frequency in-situ geoacoustic measurement system (MFIS^AMS) has been developed. The system can provide acoustic vdocity (compressional wave) and attenuation profiles of the uppermost 4 - 8 m sediment in the seafloor. It consists of 8 channels with 12 frequencies (multi-frequencies) and 0.5 - 2 MHz sampling rates. The data collected can be transmiuted in real-time. Associated with inclinometer and altimeter, it can provide the data for depth emendation. Acoustic velocity and attenuation data have been obtained from two in-situ experiments conducted in the Hangzhou Bay. 展开更多
关键词 marine sediment in-situ acoustic measurement acoustic velocity and attenuation
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Marine Engineering Geological Exploration Information System(MEGEIS):A GIS-based Application to Marine Resources Exploitation 被引量:3
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作者 SU Tianyun LIU Baohua +2 位作者 ZHAI Shikui LIANG Ruicai ZHENG Yanpeng 《Journal of Ocean University of China》 SCIE CAS 2007年第3期226-230,共5页
Based on the ArcGIS geographic information system and the ORACLE database management system,this paper reports our studies on the technology of Marine Engineering Geological Exploration Information System(MEGEIS). By ... Based on the ArcGIS geographic information system and the ORACLE database management system,this paper reports our studies on the technology of Marine Engineering Geological Exploration Information System(MEGEIS). By analyzing system structure,designing function modules and discussing data management,this paper systematically proposes a framework of technol-ogy to integrate,manage,and analyze the seabed information comprehensively. Then,the technology is applied to the design and development of the Bohai Sea Oilfield Paradigm Area Information System. The system can not only meet the practical demands of marine resources exploration and exploitation in the Bohai Sea oilfield,but also serve as a preparatory work in theory and technology for the realization of the 'Digital Seabed'. 展开更多
关键词 geographic information system (GIS) Digital Oilfield marine resources exploitation Digital Seabed marine Engineering Geological Exploration Information system (MEGEIS)
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Geological evolution of offshore pollution and its long-term potential impacts on marine ecosystems 被引量:3
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作者 Qixing Zhou Simin Wang +5 位作者 Jiaqi Liu Xiangang Hu Yuxia Liu Yuqing He Xuan He Xiaotong Wu 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第5期75-88,共14页
Populations and metropolitan centers are accumulated in coastal areas around the world.In view of the fact that they are geographically adjacent to coasts and intense anthropogenic activities,increasing global offshor... Populations and metropolitan centers are accumulated in coastal areas around the world.In view of the fact that they are geographically adjacent to coasts and intense anthropogenic activities,increasing global offshore pollution has been an important worldwide concern over the past several decades and has become a very serious problem that needs to be addressed urgently.Due to offshore pollution,various geological disasters occur in high frequency,including intensified erosion and salinization of coastal soils,frequent geological collapses and landslides and increasing seismic activities.Moreover,offshore pollution shows increasingly serious impacts on the topography and geomorphology of offshore and coastal areas,including coastal degradation,retreating coastlines and estuary delta erosion.Offshore sedimentation processes are strongly influenced by the pH changes of terrestrial discharges,and sedimentary dynamics have become extremely acute and complex due to offshore pollution.The seabed topography and hydrodynamic environment determine the fate and transport of pollutants entering offshore regions.Coastal estuaries,port basins and lagoons that have relatively moderate ocean currents and winds are more likely to accumulate pollutants.Offshore regions and undersea canyons can be used as conduits for transporting pollutants from the continent to the seabed.It is particularly noteworthy that the spatial/temporal distribution of species,community structures,and ecological functions in offshore areas have undergone unprecedented changes in recent decades.Due to increasing offshore pollution,the stable succession and development trend of marine ecosystems has been broken.It is thus important to identify and regulate the quantity,composition and transportation of pollutants in offshore regions and their behavior in marine ecosystems.In particular,crucial actions for stabilizing marine ecosystems,including increasing species and biodiversity,should be implemented to enhance their anti-interference capabilities.This review provides an overview of the current situation of offshore pollution,as well as major trends of pollutant fate and transportation from continent to marine ecosystems,transformation of pollutants in sediments,and their bioaccumulation and diffusion.This study retrospectively reviews the long-term geological evolution of offshore pollution from the perspective of marine geology,and analyses their long-term potential impacts on marine ecosystems.Due to ecological risks associated with pollutants released from offshore sediments,more research on the influence of global offshore pollution based on marine geology is undoubtedly needed. 展开更多
关键词 Global offshore pollution Geological evolution SEDIMENTATION marine ecosystem Coastal area
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Sensitivity and Uncertainty Analysis of Regional Marine Ecosystem Services Value 被引量:3
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作者 SHI Honghua ZHENG Wei +1 位作者 WANG Zongling DING Dewen 《Journal of Ocean University of China》 SCIE CAS 2009年第2期150-154,共5页
Marine ecosystem services are the benefits which people obtain from the marine ecosystem,including provisioning services,regulating services,cultural services and supporting services. The human species,while buffered ... Marine ecosystem services are the benefits which people obtain from the marine ecosystem,including provisioning services,regulating services,cultural services and supporting services. The human species,while buffered against environmental changes by culture and technology,is fundamentally dependent on the flow of ecosystem services. Marine ecosystem services become increasingly valuable as the terrestrial resources become scarce. The value of marine ecosystem services is the monetary flow of ecosystem services on specific temporal and spatial scales,which often changes due to the variation of the goods prices,yields and the status of marine exploitation. Sensitivity analysis is to study the relationship between the value of marine ecosystem services and the main factors which affect it. Uncertainty analysis based on varying prices,yields and status of marine exploitation was carried out. Through uncertainty analysis,a more credible value range instead of a fixed value of marine ecosystem services was obtained in this study. Moreover,sensitivity analysis of the marine ecosystem services value revealed the relative importance of different factors. 展开更多
关键词 marine ecosystem ecosystem services value sensitivity analysis uncertainty analysis
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Fault Detection and Diagnosis of a Gearbox in Marine Propulsion Systems Using Bispectrum Analysis and Artificial Neural Networks 被引量:3
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作者 李志雄 严新平 +2 位作者 袁成清 赵江滨 彭中笑 《Journal of Marine Science and Application》 2011年第1期17-24,共8页
A marine propulsion system is a very complicated system composed of many mechanical components.As a result,the vibration signal of a gearbox in the system is strongly coupled with the vibration signatures of other com... A marine propulsion system is a very complicated system composed of many mechanical components.As a result,the vibration signal of a gearbox in the system is strongly coupled with the vibration signatures of other components including a diesel engine and main shaft.It is therefore imperative to assess the coupling effect on diagnostic reliability in the process of gear fault diagnosis.For this reason,a fault detection and diagnosis method based on bispectrum analysis and artificial neural networks (ANNs) was proposed for the gearbox with consideration given to the impact of the other components in marine propulsion systems.To monitor the gear conditions,the bispectrum analysis was first employed to detect gear faults.The amplitude-frequency plots containing gear characteristic signals were then attained based on the bispectrum technique,which could be regarded as an index actualizing forepart gear faults diagnosis.Both the back propagation neural network (BPNN) and the radial-basis function neural network (RBFNN) were applied to identify the states of the gearbox.The numeric and experimental test results show the bispectral patterns of varying gear fault severities are different so that distinct fault features of the vibrant signal of a marine gearbox can be extracted effectively using the bispectrum,and the ANN classification method has achieved high detection accuracy.Hence,the proposed diagnostic techniques have the capability of diagnosing marine gear faults in the earlier phases,and thus have application importance. 展开更多
关键词 marine propulsion system fault diagnosis vibration analysis BISPECTRUM artificial neural networks Article
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Adjoint Assimilation in Marine Ecosystem Models and an Example of Application 被引量:2
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作者 XUQing LIUYuguang LüXianqing 《Journal of Ocean University of China》 SCIE CAS 2005年第1期14-20,共7页
This paper aims at a review of the work carried out to date on the adjoint assimilation of data in marine ecosys-tem models since 1995. The structure and feature of the adjoint assimilation in marine ecosystem models ... This paper aims at a review of the work carried out to date on the adjoint assimilation of data in marine ecosys-tem models since 1995. The structure and feature of the adjoint assimilation in marine ecosystem models are also introduced. To illustrate the application of the adjoint technique and its merits, a 4-variable ecosystem model coupled with a 3-D physical model is established for the Bohai Sea and the Yellow Sea. The chlorophyll concentration data derived from the SeaWiFS o-cean colour data are assimilated in the model with the technique. Some results are briefly presented. 展开更多
关键词 MODEL marine ecosystem adjoint assimilation cost function
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Looking for a Chinese solution to global problems:The situation and countermeasures of marine plastic waste and microplastics pollution governance system in China 被引量:2
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作者 Yue Yang Ling Chen Lan Xue 《Chinese Journal of Population,Resources and Environment》 2021年第4期352-357,共6页
As one of the top ten environmental problems to be solved in the world,marine plastic waste and microplastic pollution seriously affect the health of marine ecosystems and the sustainable development of Marine economi... As one of the top ten environmental problems to be solved in the world,marine plastic waste and microplastic pollution seriously affect the health of marine ecosystems and the sustainable development of Marine economies.It is necessary to promote the establishment of a scientific and systematic Marine plastic waste and microplastic pollution control system and take strong measures to fundamentally curb and reverse the trend of marine pollution intensification in China.This paper first explains the practical significance of marine plastic waste and microplastic pollution control from three aspects:the sustainable development of the blue economy,the structural upgrading of the pan-plastic industry,and the improvement of public health awareness.Secondly,the particularity of marine plastic waste and microplastic pollution control system is summarized from three aspects of formation mechanism,migration path and damage performance.Then,it identifies domestic and international governance strategies and action plans from the perspectives of mechanism,subject,object,and measures,summarizes existing problems in the existing marine plastic waste and microplastic pollution control system,and gives directions for future improvement.Finally,some countermeasures and suggestions are put forward to accelerate the construction of China’s marine plastic waste and microplastic pollution control system,including the formation of a cross sectoral integrated land and sea control system,a full life cycle waste management process,a multi-participation model for marine ecological and environmental governance,and a global marine pollution prevention and control system. 展开更多
关键词 Global governance marine plastic waste Microplastic pollution Land and marine development in a coordinated way Governance system
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