Buckling response of offshore pipelines under combined tension, bending, and external pressure

The buckle and collapse of offshore pipeline subjected to combined actions of tension, bending, and external pressure during deepwater installation has drawn a great deal of attention. Extended from the model initially proposed by Kyriakides and his co-workers, a 2D theoretical model which can successfully account for the case of simultaneous tension, bending, and external pressure is further developed. To confirm the accuracy of this theoretical method, numerical simulations are conducted using a 3D finite element model within the framework of ABAQUS. Excellent agreement between the results validates the effectiveness of this theoretical method. The model is then used to study the effects of several important factors such as load path, material properties, and diameter-to-thickness ratio, etc., on buckling behaviors of the pipes. Based upon parametric studies, a few significant conclusions are drawn, which aims to provide the design guidelines for deepwater pipeline with solid theoretical basis.     

网真课堂交互技术研究

网真课堂可以为网络上的异地师生实时呈现出本地课堂与远程课堂融合的情景,进行即时提问和解答等实时交互的教学活动。为了充分发挥网真课堂的优势,更好地服务于教学,提高网络教学质量,在面向网真课堂平台实际应用的设计和开发过程中,结合网络教学中各种情况的需要,增加应用视频合成、虚拟现实、体感交互、智能Agent等技术,总结提出了八大类网真课堂交互技术,兼顾了特殊情况的应用,有利于促进网络教学的反思和改进。     

以人文教育为基点,加强英语专业的文化课程设置的改革

长久以来,"学以致用"的教育理念指导着英语专业的教学与课程设置一直围绕着"听、说、读、写、译"而展开,教育者培养了一代又一代"工具型"、"适用型"人才,英语专业教育理念丧失了本来的人文性。文章就本专业目前在专业理念与课程设置中存在的问题,对山东与上海部分高校进行了调查、对比与分析,对英语专业的课程设置提出具体改革建议。     

制造业强国崛起与现代职业教育体系建设——日本的经验及启示

第二次世界大战战败后,日本迅速发展成为世界第二大经济体,关键在于制造业领域的长足进步.而日本制造业强国的崛起,与该国现代职业教育体系的建设是密不可分的.日本制造业强国崛起过程中,注重职业教育体系的市场适应性、层次多样性和开放性.这些典型的经验对我国从制造业大国向制造业强国的转变有很好的启示作用.     

Past/forward policy-making: transforming Chinese engineering education since the Reform and Opening-up

Although engineering education has played important roles in China’s growing power and influence on the world stage, engineering education policy since the Reform and Opening-up in the late 1970s has not been well documented in current English-language scholarship. Informed by historical and sociological studies of education, engineering and engineering education, this paper attempts to address this scholarly gap by relating contemporary Chinese engineering education policy-making to its broader historical, cultural and ideological contexts. Based on analysis of policy documents and reports released by the Chinese government and engineering schools, and drawing on prior scholarship of Chinese (engineering) education policy, this paper employs the concept of ‘past/forward’ as an analytic lens to interpret and understand four major areas of engineering education policy change in contemporary China: institutional reform, disciplines and majors, training objectives, and curriculum reform.     

规范性外交与欧盟气候外交政策

文章首先通过外交行为的目标、手段及影响三个方面来界定规范性外交,即规范性外交是什么的问题,接下来,分析规范性外交的内在推动力,即利益和规范在规范(或价值)为主导的政策象限中战略考量如何与规范互动.文章第二部分选取了欧盟气候外交政策作为案例,分析其目标、手段和影响维度,认为可持续发展和多边主义规范为欧盟的规范性外交提供了一个象限维度,在该象限维度中,权力政治与理性利益将穿插其中,共同影响欧盟环境外交政策.     

习近平关于教育重要论述的理论逻辑与实践逻辑

习近平关于教育的重要论述作为马克思主义教育理论中国化的最新成果,是理论逻辑与实践逻辑的统一体。就理论逻辑而言,它有宏观微观相结合、层次分明的结构逻辑,又有历史继承与时代创新相结合、承继鲜明的关系逻辑;就实践逻辑而言,它以发现问题、分析问题、解决问题为演进,形成了问题导向的实践纲领。     

Modelling and optimal control of a time-delayed switched system in fed-batch process

The main control goal of the fed-batch process is to maximize the yield of target product as well as to minimize the operation costs simultaneously. Considering the existence of time delay and the switching nature in the fed-batch process, a time-delayed switched system is proposed to formulate the 1,3-propanediol (1,3-PD) production process. Some important properties of the system are also discussed. Taking the switching instants and the terminal time as the control variables, a free terminal time delayed optimal control problem is then presented. Using a time-scaling transformation and parameterizing the switching instants into new parameters, an equivalently optimal control problem is investigated. A numerical solution method is developed to seek the optimal control strategy by the smoothing approximation method and the gradient of the cost functional together with that of the constraints. Numerical results show that the mass of target product per unit time at the terminal time is increased considerably.     

基于项目驱动的DACUM模型Java课程开发建设研究

Java语言是目前流行的一种网络编程语言,但是涉及的知识点多,入门难,高职学生基础较薄弱,学习主动性不太高,容易遇难而退。针对这一问题本文说明了项目驱动教学的重要性,根据DA-CUM模型分析介绍了项目驱动的java课程教学模式,从课程设计、课程群建设、考核方式改革、教学资源建设等方面讨论了项目驱动的DACUM模型Java课程建设应解决的相关问题,给出了贯穿式项目教学的教学设计方案,基于DACUM模型分析设置了java课程群建设相关的java、java高级编程、jsp等系列课程,具体分析并提出了项目驱动的DACUM模型《JAVA编程基础》考核方案。通过实践表明,本文所提出的基于项目驱动的DACUM高职java课程开发与建设,能够有效的加强高职院校对于java课程的教学,具有很强的拓展性,适用性很好。     

相遇信息估算概率的机会网络路由协议

在分析现有机会网络转发策略的基础上,根据Prophet和Spray and wait协议的特点提出一种相遇信息估算转发概率的机会网络路由协议(BPAS),BPAS以节点相遇的频率、相遇的连通时长和断连时长作为参量引入转发概率的计算,消息转发给转发概率大的节点,使得消息朝更靠近目的节点方向发送。仿真结果表明,BPAS协议与Epidemic协议、Prophet协议和Spray and wait协议相比,能获得更高的消息交付率和更低的通信开销,消息总转发次数更少。实验证明BPAS协议能适应于节点密度较大的机会网络环境。