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961.
Long-term data sets are discussed for three locations – a southern North Sea location, where sea states are typically dominated by wind-sea conditions, a Northwest Shelf of Australia location, where sea states are often a mix of wind-sea and swell conditions, and a Guinea Gulf location offshore Nigeria, where sea states are dominated by swell. Various types of sea state statistics that have application to availability studies are presented; but databases of these type that also include wind and current data can also be used to estimate response parameters, which can give a more direct assessment of availability, and some example statistics of these are also given. Finally, the availability of offloading an FLNG barge to carrier is evaluated for each of the data sets, for specific operability criteria. Two types of operability criteria are used in the availability evaluations, and the results compared. 相似文献
962.
963.
In the context of a deep geological repository of high-level radioactive wastes, the French National Radioactive Waste Management Agency (Andra) has conducted an extensive characterization of the Callovo-Oxfordian argillaceous rock and surrounding formations in the Eastern Paris Basin. As part of this project, an accurate 3D seismic derived geological model is needed. The paper shows the procedure used for building the 3D seismic constrained geological model in depth by combining time-to-depth conversion of seismic horizons, consistent seismic velocity model and elastic impedance in time. It also shows how the 3D model is used for mechanical and hydrogeological studies. The 3D seismic field data example illustrates the potential of the proposed depth conversion procedure for estimating density and velocity distributions, which are consistent with the depth conversion of seismic horizons using the Bayesian Kriging method. The geological model shows good agreement with well log data obtained from a reference well, located closest to the 3D seismic survey area.Modeling of the mechanical parameters such as shear modulus, Young modulus, bulk modulus indicates low variability of parameters confirming the homogeneity of the target formation (Callovo-Oxfordian claystone). 3D modeling of a permeability index (Ik-Seis) computed from seismic attributes (instantaneous frequency, envelope, elastic impedance) and validated at the reference well shows promising potential for supporting hydrogeological simulation and decision making related to safety issues. 相似文献
964.
Back analysis is a powerful tool to determine geomechanical parameters. In this article, a practical approach that employs the response surface method and MS Excel solver for back analysis is presented. The least square support vector machine (LSSVM)-based response surface is utilized to represent the nonlinear relationship between the geomechanical parameters and the monitored information and Excel solver is used to search the geomechanical parameters based on the monitoring information. We analyze the robustness and search ability of the proposed approach. On the other hand, two numerical cases on a circular tunnel and a slope are used to verify the proposed approach. Results clearly indicate that LSSVM-based response surface is effectively able to be used to identify the geomechanical parameters from the monitoring displacements. 相似文献
965.
The maximum internal tangential stress is a critical parameter for the design of the PDC (polycrystalline diamond compact) die that has been widely applied to offshore oil drilling. A new simple equation for the calculation of the stress is developed, and verified by the test data from Kingdream Corp. of China, the largest bit Company in China. An opti- mum method for the design of the PDC die is presented and demonstrated in detail, and software for the design and FEM analysis of the die is developed on the basis of the method. This software has been used in oil industry in recent years. 相似文献
966.
967.
Study of the growth of southern black and white monkfish stocks 总被引:1,自引:0,他引:1
968.
广东新丰江水库表层水体CO2分压及其影响因素 总被引:1,自引:1,他引:1
于2012年7月和2013年1月定点采集新丰江水库表层水样,测定水样的理化及生物学参数,计算水体中二氧化碳分压(p(CO_2))大小并分析其时空变化,探讨新丰江水库p(CO_2)的影响因素及其CO_2源/汇机制.结果表明:丰水期p(CO_2)变化范围为16~3545μatm,均值为999μatm,从水库上游到坝前p(CO_2)逐渐升高;枯水期p(CO_2)变化范围为399~1355μatm,均值为756μatm,从水库上游到坝前p(CO_2)呈下降趋势.丰水期p(CO_2)受温度影响较小,与营养盐(NO-3、DSi)浓度呈正相关,与叶绿素a(Chl.a)、溶解有机碳(DOC)浓度呈负相关,与溶解无机碳(DIC)浓度没有明显相关性;枯水期p(CO_2)受温度影响也较小,受碳酸盐体系的影响,与NO-3、DSi、Chl.a、DIC浓度呈正相关,与DOC浓度没有明显相关性.新丰江水库相对于大气来说是一个通量值偏低的CO_2源. 相似文献
969.
970.
Yu Hongming Hu Yanxin Engineering Faculty China University of Geosciences Wuhan 《中国地质大学学报(英文版)》2001,12(2)
INTRODUCTIONTheYujiapengtunnel,animportantpartofJuguiroadinZiguioftheThreeGorges,locatedonthesouthernbeachoftheYangtzeRiver,isveryimportanttotheThreeGorgesproject,totheeconomicdevelopmentofthisareaandfinallytothemigrationproject.Thistunnel,about 2kmlong ,… 相似文献