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Simulation of Horizontal-Two-Dimension Focused Waves Using A Two-Layer Boussinesq-Type Model

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China Ocean Engineering 2023年第5期37卷 725-737页

作者： ZOU Wen-feng WANG Ping LIU Zhong-bo FANG Ke-zhao SUN Jia-wen ZHANG Ning-chuan Key Laboratory of coastal and offshore engineering Dalian University of TechnologyDalian 116024China State Environmental Protection Key Laboratory of marine Ecosystem Restoration National Marine Environmental Monitoring CenterDalian 116023China Dalian Maritime University College of Transportation EngineeringDalian 116024China

Accurate simulation of the horizontal-two-dimension(H2D)focused wave group in deep water requires high accuracy of a numerical *** two-layer Boussinesq-type model(Liu and Fang,2016;Liu et al.,2018)with the highest spatial derivative of 2 has high accuracy in both linear and nonlinear *** on the further development of the velocity equations(Liu et al.,2023),the H2D numerical model for water waves is established with the prediction-correction-iteration model in the finite difference method,and a composite fourth-order Adams-Bashforth-Moulton scheme is used for time *** wave generation method proposed by Hsiao et al.(2005)is applied and calibrated in this H2D *** numerical calculations lead to the following three main conclusions:First,compared with the analytical solution of Stokes linear waves,the calculated velocity profiles show higher accuracy by using the improved velocity ***,the simulations of the focused multidirectional wave group are carried out,and good agreements are found,demonstrating that the present H2D numerical model shows high accuracy in simulating focused multidirectional wave groups,and the effectiveness of the improved velocity formulas is also ***,the velocity profiles throughout the computational domain at the time of maximum wave crest are ***,the FFT method is used to obtain the amplitude with different frequencies for several locations,and the changes of the wavelet energy spectrum at different locations are presented for several cases.

关键词： focused wave horizontal-two-dimension model finite difference method nonlinear property

Reliability indexes for multi-AUV cooperative systems

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Journal of Systems Engineering and Electronics 2017年第1期28卷 179-186页

作者： Qingwei Liang Tianyuan Sun Dongdong Wang College of marine Science and technology Northwestern Polytechnical UniversityXi’an 710072China The 32th Research Institute of China Electronic technology group Corporation Shanghai 200233China

With the development of multi-autonomous underwater vehicle (AUV) cooperative systems, the evaluation of their reliability is becoming more and more important. Aimed at the characteristics of the system, three reliability indexes-standard entropy of rank distribution, all-terminal reliability and standard natural connectivity are determined in this paper. Topology structure and underwater acoustic communication are considered. The calculation methods of the three reliability indexes are proposed, and the characteristics of these indexes are analyzed. The reliability indexes of two multi-AUV cooperative systems are obtained as examples. Results show that these three indexes reflect different aspects of reliability for multi-AUV cooperative systems. This paper provides some methods to evaluate the reliability of multi-AUV cooperative systems, which is of practical value. © 1990-2011 Beijing Institute of Aerospace Information.

关键词： Cooperative communication offshore pipelines Reliability Underwater acoustics

Time-varying reliability indexes for multi-AUV cooperative system

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Journal of Systems Engineering and Electronics 2017年第2期28卷 401-406页

作者： Qingwei Liang Tianyuan Sun Dongdong Wang College of marine Science and technology Northwestern Polytechnical University Xi’an 710072 China The 32nd Research Institute of China Electronic technology group Corporation Shanghai 200233 China

With the development of multi-autonomous underwater vehicle (AUV) cooperative systems, the evaluation of their reliability is becoming more and more important. Since AUVs are always in motion, the reliability of the system is not stationary, but it varies with time. This paper studies the time-varying reliability evaluation indexes for multi-AUV cooperative systems. Aimed at elucidating the characteristics of the system, by considering the motion of the AUVs, two time dependent reliability evaluation indexes, natural connectivity and all-terminal reliability of the basic reliability indexes, are determined with the graph theory. Then the time-varying reliability of multi-AUV cooperative systems is evaluated combining with an actual example. This paper provides a method to evaluate the time-varying reliability of multi-AUV cooperative systems. © 2017 Beijing Institute of Aerospace Information.

关键词： Graph theory offshore pipelines Reliability Reliability theory

An Installation System of Deepwater Risers by An S-Lay Vessel

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China Ocean Engineering 2011年第1期25卷 139-148页

作者：段梦兰王懿 Segen ESTEFEN 何宁李丽娜陈邦敏 School of Naval Architecture and marine Engineering Dalian University of Technology offshore Oil/Gas Research Center China University of Petroleum COPPE Federal University of Rio de Janeiro Design Division CNOOC Engineering

Along with the consumption increase of the petroleum products, more countries have transferred their attentions to the offshore fields, especially the deepwater oil and gas reserves. For deepwater exploitation, the risers must be installed to act as the conduits connecting surface platforms to subsea facilities. In this paper, the typical risers sorted by different classes are introduced, and the correspondent installation methods are presented. By investigating the recent projects performed in the deepwater hot spots, and combining the challenges of HYSY20 l for riser installation, a lifting device developed for assisting riser installation is proposed and detailed to satisfy the installation of deepwater risers in the LW3-1 Gas Field of 1500 m in the South China Sea. Tests on both the functions and performances of such a new system exhibit the satisfaction of meeting all challenging requirements of HYSY201 for application to riser installation in waters up to a depth of 3000 m in the South China Sea.

关键词： deepwater riser riser installation lifting device LW3-1 Gas Field South China Sea

Application of a collaborative modelling and strategic fuzzy decision support system for selecting appropriate resilience strategies for seaport operations

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Journal of Traffic and Transportation Engineering(English Edition) 2014年第3期1卷 159-179页

作者： Andrew John Zaili Yang Ramin Riahi Jin Wang Department of marine and offshore Engineering School of Engineering Technology and Maritime OperationsLiverpool John Moores UniversityLiverpoolMersey sideUK

The selection of an appropriate resilience investment strategy to optimize the operational efficiency of a seaport is a challenging task given that many criteria need to be considered and modelled under an uncertain environment. The design of such a complex decision system consists of many subjective and imprecise parameters contained in different quantitative and qualitative forms. This paper proposes a fuzzy multi-attribute decision making methodology for the selection of an appropriate resilience investment strategy in a succinct and straightforward manner. The decision support model allows for a collaborative modelling of the system by multiple analysts in a group decision making process. Fuzzy analytical hierarchy process （FAHP） was utilized to analyse the complex structure of the system to obtain the weights of all the criteria while fuzzy technique for order of preference by similarity to ideal solution （TOPSIS） was employed to facilitate the ranking process of the resilience strategies. Given that it is often financially difficult to invest in all the resilience strategies, it is envisaged that the proposed approach could provide decision makers with a flexible and transparent tool for selecting appropriate resilience strategies aimed at increasing the resilience of seaport operations.

关键词： seaport resilience FAHP TOPSIS decision making

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集装箱船双燃料发动机投资的环境与经济评价

哈尔滨工程大学学报（英文版） 2023年第4期22卷 823-836页

作者： Çağlar Karatuğ Emir Ejder Mina Tadros Yasin Arslanoğlu Istanbul Technical University Maritime Faculty34940TuzlaIstanbulTurkey marine Offshore and Subsea Technology GroupMechanical Engineering and Marine TechnologySchool of EngineeringNewcastle UniversityNewcastle Upon TyneNE17RUUK Department of Naval Architecture and marine Engineering Faculty of EngineeringAlexandria UniversityAlexandria 21544Egypt

In this study,environmental and economic examinations of Liquefied Natural Gas(LNG)investments are conducted.A year-long noon report data is received from a container ship and LNG conversion is *** from both the fuel expenses and the amount of the emissions are calculated and *** eliminate the fuel consumption uncertainties in future operation periods of the stated ship,different scenarios that simulate various fuel consumption statuses are created and analyzed within the Monte Carlo Simulation ***,calculations are made with two different time prices,*** and half year *** a result of the analyses,LNG can provide high environmental benefits since it reduces 99%for SOx,95%for PM10,95%for PM2.5,41%for CO_(2),and 82%for NOx,*** is also determined that LNG investment is highly sensitive to fuel *** addition,the LNG usage can be beneficial for maritime companies in terms of marine policies such as paying carbon tax based on the expanding European Union Emission Trade System to maritime ***,it needs supportive carbon reduction method to comply with the maritime decarbonization *** study has great importance in that the economic analysis way presented is able to adapt any alternative fuel system conversion for the maritime industry.

关键词： Dual-fuel engine Monte Carlo simulation Emission reduction Maritime transportation Economic analysis Environmental analysis

Effect of Carbonation and Drying-Wetting Cycles on Chloride Diffusion Behavior of Coral Aggregate Seawater Concrete

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Journal of Ocean University of China 2022年第1期21卷 113-123页

作者： DA Bo LI Yipeng YU Hongfa MA Haiyan CHEN Haoyu DOU Xuemei WU Zhangyu College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Department of Civil and Airport Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Coastal Disaster and Defence of Ministry of Education Hohai UniversityNanjing 210098China Nantong Institute of marine and offshore Engineering Hohai UniversityNantong 226300China CCCC Infrastructure Maintenance group Company Limited Beijing 100010China

Based on seawater immersion,drying-wetting cycles,carbonation and drying-wetting cycles for coral aggregate sea-water concrete(CASC)with different strength grades,the effect of carbonation and drying-wetting cycles on chloride diffusion be-havior of CASC is *** results show that the free surface chloride concentration(Cs),free chloride diffusion coefficient(Df)and time-dependent index(m)of CASC in the drying-wetting cycles is obviously higher than that in seawater *** Df and m of CASC of carbonation and drying-wetting cycles is higher than that in the drying-wetting *** increases the Df and m of CASC,which is against CASC to resist chloride *** corrosion possibility of CASC structures in different ex-posed areas is as follows:splash zone(carbonation and drying-wetting cycles)>tidal zone(drying-wetting cycles)>underwater zone(seawater immersion).Besides,the chloride diffusion rate of C65-CASC is 17.8%-63.4%higher than that of C65-ordinary aggre-gate concrete(OAC)in seawater immersion(underwater zone).Therefore,anti-corrosion measures should be adopted to improve the service life of CASC structure in the oceanic environment.

关键词： coral aggregate seawater concrete chloride diffusion seawater immersion drying-wetting cycles carbonation and drying-wetting cycles

Evolution of the Pearl River and its Implication for East Asian Continental Landscape Reversion

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Acta Geologica Sinica(English Edition) 2021年第1期95卷 66-76页

作者： ZHANG Hao CUI Yuchi QIAO Peijun ZHAO Meng XIANG Xuhong State Key Laboratory of marine Geology Tongji UniversityShanghai 200092China Earth Dynamics Research group the Institute for Geoscience Research(TIGeR)School of Earth and Planetary SciencesCurtin UniversityGPO Box U1987Australia Tianjin Branch of China National offshore Oil Corporation Tianjin 300459China Shenzhen Branch of China National offshore Oil Corporation Ltd. Shenzhen 518054China

As the link connecting the South China Continent and the northern South China Sea(SCS),the Pearl River is the focus of sedimentology and petroleum geology *** evolutionary process and controlling factors are of great significance in revealing the East Asian continental landscape reorganization during the Late *** on published data,’source-to-sink’provenance analyses allow systematic deliberation on the birth and evolutionary history of the Pearl *** to the Oligocene/Miocene boundary,an abrupt shift in the sedimentary composition indicates significant westward and northward expansion of the river’s watershed area,followed by the establishment of a near-modern fluvial *** sedimentary change generally concurred with a series of regional geological events,including the onset of the Yangtze throughflow,large-scale development of the loess plateau,and formation of the northwestern arid zone and Asian Monsoon *** major changes in the geology-climate-ecoenvironment system are in close response to the process of the Cenozoic Xizang(Tibetan)Plateau ***,the East Asian continental landscape and most of midCenozoic drainage systems underwent critical reversion into east-tilting,or east-flowing networks.

关键词： Oligocene–Miocene landscape reversion source to sink provenance analyses East Asian continental landforms Pearl River South China

Evaluation of the submarine debris-flow hazard risks to planned subsea pipeline systems: a case study in the Qiongdongnan Basin, South China Sea

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Acta Oceanologica Sinica 2023年第5期42卷 139-153页

作者： Mingquan Huang Xuesheng Qian Jingping Xu Xuecheng Li School of Environment Harbin Institute of TechnologyHarbin 150001China Department of Ocean Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Southern marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China China offshore Fugro Geosolutions(Shenzhen)Corporation Limited Shenzhen 518067China

The ever-increasing deepwater oil and gas development in the Qiongdongnan Basin,South China Sea has initiated the need to evaluate submarine debris-flow hazard risks to seafloor *** paper presents a case study on evaluating the debris-flow hazard risks to the planned pipeline systems in this *** used a numerical model to perform simulations to support this quantitative ***,one relict failure interpreted across the development site was *** back-analysis modeling was used to validate the applicability of the rheological ***,this model was applied to forecast the runout behaviors of future debris flows originating from the unstable upslope regions considered to be the most critical to the pipeline systems surrounding the Manifolds A and *** model results showed that the potential debris-flow hazard risks rely on the location of structures and the selection of rheological *** the Manifold B and connected pipeline systems,because of their remote distances away from unstable canyon flanks,the potential debris flows impose few ***,the pipeline systems around the Manifold A are exposed to significant hazard risks from future debris flows with selected rheological *** results are beneficial for the design of a more resilient pipeline route in consideration of future debris-flow hazard risks.

关键词： submarine debris flow pipeline manifold hazard evaluation route optimization Qiongdongnan Basin