The breaking of wind-generated waves is an important phenomenon in the ocean, having close relation to many aspects of the ocean, such as air-sea interaction, ocean wave dynamics, oceanic remote sensing and ocean engi...The breaking of wind-generated waves is an important phenomenon in the ocean, having close relation to many aspects of the ocean, such as air-sea interaction, ocean wave dynamics, oceanic remote sensing and ocean engineering. The first problem encountered in both its theoretical study and practical measurement is how to detect the breaking of waves.展开更多
This study explores the arrivals of water pipeline break failures. The aim is to assist the facility manager in the decision making process. Based on characteristics of the data set ranging from 2011 to 2014, two step...This study explores the arrivals of water pipeline break failures. The aim is to assist the facility manager in the decision making process. Based on characteristics of the data set ranging from 2011 to 2014, two steps of analysis were presented in the paper. This first step is the analysis of partially complete data set (2011 data). The 2-sample KS test is adopted to check the similarity between this data set and the entire data set with no underlying distribution implied. In order to conduct the reliability analysis, the Weibull distribution is adopted to evaluate the data. For annual data set, the 2-parameter Weibull distribution fits data sets pretty well. The shape parameters are a little greater than 1, indicating a slightly increasing arrival rate of such failures. For the entire data set, the 3-parameter Weibull tends to fit the data better than the 2-parameter Weibull. The shape parameter is well above 1, indicating an increasing arrival rate of the failures. To eliminate the impact of missing points for the 2011 data set, data from 2012 to 2014 were also considered as a new set, the Weibull distribution generated a decent fitting. The shape parameter is a little greater than 1. Therefore, there is a slightly increasing arrival rate of those pipeline failures. Results from this study provide decision makers valuable information in terms of whether additional efforts shall be made to enhance the system’s performance in order to reduce the failure rate.展开更多
The wave loads acting on a breakwater resting on seabed include not only the wave force from the wave field around the structure but also the wave-induced seepage pressure acting on the base of breakwater.The latter i...The wave loads acting on a breakwater resting on seabed include not only the wave force from the wave field around the structure but also the wave-induced seepage pressure acting on the base of breakwater.The latter is also a circumstance load which can not be neglected in engineering design.This paper presents a closed-form analytical solution of wave-induced seep- age pressure acting on the base of breakwater resting on an infinite-depth porous elastic seabed. Based on the Biot's consolidation theory,the soil deformation and the compressibility of pore wa- ter are considered.The water wave pressure on sea bottom is determined by the linear water wave theory.The numerical results of uplifting force and moment caused by the wave-induced seepage pressure are given and the influences of soil deformation and pore water compressibility on the calculation results are discussed.展开更多
文摘The breaking of wind-generated waves is an important phenomenon in the ocean, having close relation to many aspects of the ocean, such as air-sea interaction, ocean wave dynamics, oceanic remote sensing and ocean engineering. The first problem encountered in both its theoretical study and practical measurement is how to detect the breaking of waves.
文摘This study explores the arrivals of water pipeline break failures. The aim is to assist the facility manager in the decision making process. Based on characteristics of the data set ranging from 2011 to 2014, two steps of analysis were presented in the paper. This first step is the analysis of partially complete data set (2011 data). The 2-sample KS test is adopted to check the similarity between this data set and the entire data set with no underlying distribution implied. In order to conduct the reliability analysis, the Weibull distribution is adopted to evaluate the data. For annual data set, the 2-parameter Weibull distribution fits data sets pretty well. The shape parameters are a little greater than 1, indicating a slightly increasing arrival rate of such failures. For the entire data set, the 3-parameter Weibull tends to fit the data better than the 2-parameter Weibull. The shape parameter is well above 1, indicating an increasing arrival rate of the failures. To eliminate the impact of missing points for the 2011 data set, data from 2012 to 2014 were also considered as a new set, the Weibull distribution generated a decent fitting. The shape parameter is a little greater than 1. Therefore, there is a slightly increasing arrival rate of those pipeline failures. Results from this study provide decision makers valuable information in terms of whether additional efforts shall be made to enhance the system’s performance in order to reduce the failure rate.
文摘The wave loads acting on a breakwater resting on seabed include not only the wave force from the wave field around the structure but also the wave-induced seepage pressure acting on the base of breakwater.The latter is also a circumstance load which can not be neglected in engineering design.This paper presents a closed-form analytical solution of wave-induced seep- age pressure acting on the base of breakwater resting on an infinite-depth porous elastic seabed. Based on the Biot's consolidation theory,the soil deformation and the compressibility of pore wa- ter are considered.The water wave pressure on sea bottom is determined by the linear water wave theory.The numerical results of uplifting force and moment caused by the wave-induced seepage pressure are given and the influences of soil deformation and pore water compressibility on the calculation results are discussed.