Ice-Induced Fatigue Analysis by Spectral Approach for Offshore Jacket Platforms with Ice-Breaking Cones

The spectral methods and ice-induced fatigue analysis are discussed based on Miner's linear cumulative fatigue hypothesis and S-N curve data.According to the long-term data of full-scale tests on the platforms in the Bohai Sea,the ice force spectrum of conical structures and the fatigue environmental model are established.Moreover,the finite element model of JZ20-2MSW platform,an example of ice-induced fatigue analysis,is built with ANSYS software.The mode analysis and dynamic analysis in frequency domain under all kinds of ice fatigue work conditions are carried on,and the fatigue life of the structure is estimated in detail.The methods in this paper can be helpful in ice-induced fatigue analysis of ice-resistant platforms.     

A Time-Domain Coupled Model for Nonlinear Wave Forces on A Fixed Box-Shaped Ship in A Harbor

A 2-D time-domain numerical coupled model is developed to obtain an efficient method for nonlinear wave forces on a fixed box-shaped ship in a harbor.The domain is divided into an inner domain and an outer domain.The inner domain is the area beneath the ship and the flow is described by the simplified Euler equations.The other area is the outer domain and the flow is defined by the higher-order Boussinesq equations in order to consider the nonlinearity of the wave motions.Along the interface boundaries between the inner domain and the outer domain,the volume flux is assumed to be continuous and the wave pressures are equal.Relevant physical experiment is conducted to validate the present model.It is shown that the numerical results agree with the experimental data.Compared with the coupled model with the flow in the inner domain governed by the Laplace equation,the present coupled model is more efficient and its solution procedure is more simple,which is particularly useful for the study on the effect of the nonlinear wave forces on a fixed box-shaped ship in a large harbor.     

研学旅行中培育地理实践力素养的策略研究

研学旅行立足于真实情境,促进学生合作、自我发展、参与体验与创造,是"地理实践力"核心素养得以习得的重要载体之一。本文初步探究了地理实践力的内涵、研学旅行对地理实践力的体现,并尝试提出了研学旅行中培育地理实践力素养的具体策略。     

课堂教学中地理实践力培养存在的问题及优化建议

地理实践力是地理核心素养的重要组成部分,是地理课堂教学中核心素养培养的薄弱环节。本文针对高中地理课堂中中学生地理实践力培养存在的问题进行探究,并从教学目标、教学内容、教学方法、教学评价等方面对地理实践力的培养提出优化建议,以期为广大教师地理教学提供借鉴与参考。     

面向地理实践力培养的Sun Surveyor手机软件的应用研究——以“地球的运动”为例

信息技术的应用和发展对改变学生的学和教师的教具有重要作用。从地理实践力的培养要求出发,以"观察、使用工具和实践想法"三个角度为切入点,借助Sun Surveyor并结合地球运动进行案例设计。希望能为地理教师运用信息技术进行教学提供思路,以期更好地落实地理实践力的培养。     

基于地理实践力培养的研学课程实践——以“嘉陵明珠 合碚研行”研学旅行课程为例

为了提高地理研学旅行的实效性,特别参照《普通高中地理课程标准(2017年版)》,聚焦重庆市普通高中学生地理实践力的培养和应用。依托嘉陵江干流重庆合川北碚段丰富的地理资源,从课程设计、课程实施、课程评价、课程反思等方面,尝试将地理研学旅行课程化。通过记录并分析本课程的具体实施过程,对其进行认真反思,提出应从前置性学习、师资搭配、课程容量等方面,优化地理研学旅行课程的设计和实施。