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再分析风场资料已广泛应用于我国舟山群岛海域可再生能源评估、海洋灾害预防决策以及港口运维和船舶运输等涉海发展领域,然而不同业务机构所提供的再分析数据在舟山近海的性能表现不一,严重阻碍了此类数据的有效应用。基于2018年全年单点浮标观测资料,综合评价了舟山群岛近海面(10 m)风场的长期变化趋势,并利用误差分析和风玫瑰图等统计工具对6种主流海表风场再分析资料,包括:ECMWF第五代全球大气再分析数据(the 5th generation ECMWF atmospheric reanalysis,ERA5)、NECP第二版全球高分辨率再分析数据(climate forecast system version 2,CFSv2)、美国宇航局物理海洋学分布存档中心的多卫星融合资料(cross-calibrated multi-platform,CCMP)、日本55年再分析数据(Japanese 55-year reanalysis,JRA-55)、第二版现代研究与应用回顾性分析数据(modern-era retrospective analysis for research and applications version 2,MERRA-2)和ECMWF哥白尼大气监测服务再分析数据(the Copernicus Atmosphere Monitoring Service,CAMS)在时间变化特征上进行了对比与评估。研究表明:在综合性能方面,ERA5对风场的再现能力最优,其次为JRA-55;在要素可信度方面,ERA5对风速的再现情况相对较优,而CFSv2的风向再现情况较好;风场产品在不同季节的模拟能力有所差异;不同风场产品在不同风速区间的重构能力也有所不同;在全年风向分布方面,各再分析资料都存在显著的东向偏差。研究结果为不同应用场景下风场资料的选取提供评估依据,并为进一步开发适用于舟山群岛近海的高精度长周期风场数据产品奠定基础。 相似文献
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水下井口系统环空金属密封总成设计是水下油气装备国产化核心技术之一。前期国内相关研究人员已在密封设计、密封机理等方面形成共识,但密封性能评价的全面性和准确性依旧存在不足。鉴于此,提出考虑高低温影响的金属密封总成性能评价方法,构建了“有限元分析+室内测试+无损探伤”的评价流程。评价结果显示:温度是金属密封设计及性能评价过程中不可忽略的重要影响因素;设计温度范围内,该金属密封总成的密封性能及主体结构强度满足设计要求,但仍不同程度地受到温度变化影响;相对于常规方法,该评价方法更加全面准确,可为该领域其它密封设计提供借鉴和参考。 相似文献
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《Ocean & Coastal Management》1999,42(9):767-789
The experience of 19 donor agencies and international organizations with evaluation of ICM initiatives is surveyed to analyze the differences in the evaluative purposes and methodologies and their relevance to a “learning-based approach” to ICM. We group evaluation into three broad categories: performance evaluation, management capacity assessment and outcomes evaluation. Performance evaluations address the quality of project implementation, and the degree to which project goals are achieved. Management capacity assessments are conducted to determine the adequacy of management structures and governance processes as these relate to generally accepted international standards and experience. Outcome assessments evaluate the impacts of a coastal management initiative upon coastal resources and the associated human society(s). The survey show that most donor evaluations emphasize performance evaluation, but usually combine elements of all three types. There is strong interest among international donors investing in coastal management in learning from and advancing coastal management practice. If donors are to maximize leaning and commit to an adaptive approach to ICM they will need to modify the manner in which project monitoring and evaluations are conducted, analyzed and distributed. A number of modifications to current approaches to evaluation are suggested in the paper. 相似文献
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海洋环境参数监测传感器的性能是海洋环境监测参数数据质量的保障。文章以常用的海水温度、电导率、浊度和叶绿素传感器为评估对象,利用同一台仪器连续多年的校准数据实现传感器的稳定性评价。当漂移系数在1附近时,表明传感器性能稳定,当漂移系数大于或小于1时,表明传感器测量值发生漂移;由历年校准数据计算的漂移系数可实现各传感器校准周期内数据的修正,修正前各传感器的测量误差大且呈单向增量变化,修正后的误差降至传感器最大允许误差且呈正态分布。利用历史计量数据建立的传感器性能评价模型可为用户提供长期的传感器稳定性评价,有利于提升海洋环境监测传感器的性能和数据的准确性,拓展计量数据的服务能力。 相似文献
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Evaluation of a regional climate model using in situ temperature observations over the Balkan Peninsula 总被引：1，自引：0，他引：1
By E. KOSTOPOULOU K. TOLIKA I. TEGOULIAS C. GIANNAKOPOULOS S. SOMOT C. ANAGNOSTOPOULOU P. MAHERAS 《地球，A辑:动力气象学与海洋学》2009,61(3):357-370
Climate model data provide large, dense coverage and long time-series, characteristics that are advantageous in the study of climate. However, it is not recommended that such data be used in any region without prior evaluation of their reliability based on comparisons with in situ observations. In this study, the accuracy of maximum and minimum temperature data from the ALADIN-Climate regional climate model (with a 25-km horizontal resolution driven at the lateral boundaries by the ERA-40 reanalysis) have been assessed for 53 stations across the Balkan Peninsula. The model temperatures corresponding to each station were extracted from their nearest land grids. The model data were first compared with observations and subsequently examined for their ability to identify extreme temperature events. In general, the model was found to be quite accurate in describing the seasonal cycle, as well as simulating the spatial distribution of temperature. Simulations were more realistic for stations along coastlines, highlighting the constraints of the topographic forcing in the simulations. Assessing the performance of the model to determine extremes (warm and cold spells), it was found to be better at detecting cold spells and has a tendency toward overestimating the frequency of occurrence of warm spells, particularly in summer. 相似文献
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二次生烃机理在中下扬子高演化烃源岩评价中的应用 总被引：1，自引：0，他引：1
在野外地质观察、油气地球化学和样品分析的基础上,通过总结二次生烃特征和生烃机理,将其应用到中下扬子区海相高演化烃源岩生烃潜力的评价。模拟实验结果表明,二次生烃具有明显的迟缓现象,也仍具有相对的生烃高峰,二次生烃量与一次生烃量的总和小于连续热演化的生烃量,这些特征都与一次生烃的演化程度密切相关,初始演化程度成为评价高演化烃源岩二次生烃潜力的关键因素。中下扬子区中—古生界发育的6套烃源岩中,下二叠统、下志留统和下寒武统烃源岩具有较强的生烃能力,是主要的烃源层。下古生界烃源岩进入生烃时间较早,在强烈的构造运动背景下,生成的油气难以保存;上古生界烃源岩热演化程度相对较低,燕山—喜山期的再次沉降地区成为二次生烃的供源区。因此,下古生界台地相区和上古生界烃源岩具有一定的二次生烃潜力。 相似文献
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Ma Peisun Ma Lie Lu Shunshou Associate Professor Shanghai Jiaotong University Shanghai Graduate Shanghai Jiaotong University Shanghai Engineer Shanghai Jiaotong University Shanghai 《中国海洋工程》1991,(4)
To fulfil the need of development of offshore oil floating production system, the performance of turret assembly in an inboard turret mooring system has been investigated in the paper. By means of systematic evaluation, the optimal structure of the turret for single-point mooring systems has been determined. Through model tests of a turret mooring system, several groups of data such as forces, moments and displacements under different environmental conditions have been obtained. Stresses and strains of the turret structure have been calculated by means of the finite element method corresponding to the situation in the model experiment. The study shows that the selected turret structure and the designed turret assembly are technically feasible. 相似文献
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青藏高原中东部夏季降水主要表现为东北和东南反位相变化的双极型特征。采用经验正交函数(empirical orthogonal function,EOF)分解方法,系统性地评估参与第五次耦合模式比较计划 (Coupled Model Intercomparison Project Phase 5,CMIP5)历史模拟试验的 47 个模式对青藏高原中东部夏季降水双极型变化特征的模拟能力。结果表明,大多数模式基本可以反映青藏高原中东部夏季降水东北部和东南部反位相的变化特征。模式间 EOF 分析结果表明在35°N 以南的东西向模拟偏差是 CMIP5 模式模拟降水空间型态的主要偏差,且大多数模式对时间系数的模拟效果差于空间型态。文中定义了一个综合评估指标 Snew 来定量描述模式对空间型态、时间系数以及方差贡献的综合模拟效果。由定量评估结果来看,MIROC-ESM、HadGEM2-CC 和 ACCESS1-0 (FIO-ESM、 HadGEM2-AO 和 MIROC-ESM-CHEM)模式对观测降水的 EOF1(EOF2)模态的综合模拟能力相对较好,而 GISS 系列模式、CESM1-CAM5 和 MPI-ESM-LR (CMCC-CESM、MPI-ESM-MR 和 GFDL- CM3)模式对观测降水的 EOF1(EOF2)模态的综合模拟效果较差。由 EOF1 和 EOF2 的综合评估结果来看,MIROC-ESM-CHEM模式对观测降水的 EOF1 和 EOF2 模态的综合模拟效果最好。 相似文献
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Reliable performance is the key requirement for instruments used in offshore moored buoys for cyclone monitoring, as under performance of the sensors can have a serious impact on the societal protection, and in addition, lead to costly repair and reinstallations. The instrument selection and application practices are based on the experiences of the global scientific community, and their performances are monitored based on IEC61508 standards. Reliability modeling based on experiences in the operation and maintenance of moored surface buoys for approximately two decades has identified that the sensor suite used for cyclone monitoring has a Mean Time Between Failure of 0.6 years, which is the basis of the implemented reliability centered maintenance strategies. As this is the first attempt to study the performance of such moored buoy instruments which have cumulatively clocked more than 7.3 million demanding offshore instrument-hours, the data presented shall serve as input for the offshore environmental instrument system design. 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
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由于自然因素和人类活动的影响等原因,世界很多海滩经受着侵蚀和破坏。而利用人工养护工程来保护和恢复海滩具有养护效果较明显、干滩面积明显增加以及不破坏环境景观的优点,目前得到越来越多国家的认可。国外由于养滩历史较久,养滩工程后的监测和质量评价不仅开展得早,而且已经成为工程的一个重要部分。评价指标已经比较完善,甚至有些国家已经将养滩效果评价列入法规框架之中。我国的海滩养护工程在十几年前才开始,虽然工程量逐年增长,但是对海滩养护工程施工后的工程监测和工程评价却较少涉及。本文对美国、荷兰、英国、丹麦以及我国等国家的海滩养护工程的工程评价工作进行总结,从而提出适用于我国工程特点的养滩工程质量评价因子和方法。 相似文献
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Experimental model tests were conducted to predict the performance of two sets of metal and plastic bi-directional tidal turbine rotors. This test programme aims to provide reliable and accurate measurement data as references for developers, designers and researchers on both model and full scale. The data set presented in this paper makes available the detailed geometry and motion parameters that are valuable for numerical tools validation. A rotor testing apparatus that was built using an off-the-shelf K&R propeller dynamometer, its configuration, testing set-up, calibration of the apparatus and data acquisition are described. Comparison analysis between the metal and plastic rotors hydrodynamic performance in terms of torque, drag and derived power and drag coefficients are also presented. The results show a substantial decrease in maximum power performance for the plastic rotors – about 40% decrease at a tip speed ratio of around 3.0, compared with rigid metal rotors. The plastic rotors have also a much higher cut-in speed. It showed that materials for rotor models with low rigidity such as polyamide (nylon) produced by selective laser sintering (SLS) systems may substantially under-predict power generation capacity. As a result, they are considered unsuitable for rotor model performance evaluation. 相似文献
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The energy efficiency of ocean-going vessels can be increased through various operational considerations, such as improved cargo arrangements and weather routing. The first step toward the goal of maximizing the energy efficiency is to analyze how the ship's powering performance changes under different operational settings and weather conditions. However, existing analytical models and empirical methods have limitations in reliably estimating the powering performance of full-scale ships in real operating conditions. In this study, machine learning techniques are employed to estimate the powering performance of a full-scale ship by constructing regression models using the ship's operational data. In order to minimize the risk of overfitting in the regression process, domain knowledge based on physical principles is combined into the regression models. Also, the uncertainty of the estimated performance is evaluated with consideration of the environmental uncertainties. The obtained regression models can be used to predict the ship speed and engine power under different operational settings and weather conditions. 相似文献
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