冰区海上石油钢结构的安全可靠性分析

冰区海上钢结构与冰的相互作用,远较海浪为甚.冰激振动引起的交变应力,将会使海上石油钢结构发生疲劳与断裂玻坏.因此,冰区设计新结构物或是对服役期间海上钢结构的安全评估,均需进行疲劳及断裂的安全可靠性分析.文章分别从强度与应力两个方面,给出了海上结构用钢在低温及冰载作用下的强度试验及其结果和概率分布;提出了冰区海上的疲劳环境、疲劳工况新概念;推出了冰区海上疲劳环境中等效应力幅的计算方法;进行了冰区海上石油钢结构的疲劳与断裂失效的可靠性分析.     

冰区平台动态疲劳可靠性更新研究

提出考虑腐蚀缺陷的冰区平台动态疲劳可靠性模型,并基于Bayes理论研究检测与维修对平台动态疲劳可靠性更新。以疲劳寿命为控制量,确定基于断裂力学方法的冰区平台动态疲劳可靠性功能函数;分析腐蚀对平台动态疲劳可靠性的影响,建立考虑疲劳与腐蚀交互作用的冰区平台动态可靠性模型;基于Bayes理论对腐蚀预测模型进行修正,通过修正腐蚀模型实现对平台动态疲劳可靠性更新。最后以渤海一平台为例,采用所建立的模型对其动态疲劳可靠性进行分析,并根据检测与维修资料进行更新,结果表明由于疲劳和腐蚀的作用,平台可靠性随着服役时间的增长迅速下降,检测与维修均对平台动态疲劳可靠性有较大影响。     

海洋平台冰激疲劳时域精细评估

为了评估冰区平台在服役期内的安全可靠性,给出了平台冰激疲劳时域精细评估的详细流程。根据海冰漂移方向、冰速和冰厚的概率分布特征,确立冰激振动分析的24个疲劳予工况。考虑平台桩柱的不同结构型式和冰-结构耦合作用．分别采用简化冰力函数模型和Sodhi改进模型对平台中锥体结构和直立桩柱结构进行冰激动态响应分析;建立管节点精细有限元模型计算热点应力集中系数,从而得到管节点的疲劳应力时程,并利用雨流计数法进行统计．计算整个疲劳环境的等效应力幅以及相应的循环次数,最后利用Miner线性累积损伤准则计算疲劳损失和疲劳寿命。结果表明：4根钭撑杆上的支管冰激疲劳损伤最大,应作为今后检测的重点部位。     

液压举升装置在海上平台侧钻作业的可行性研究

为解决海上无修井机平台、低配修井机平台及靠泊受限平台的侧钻作业难题，针对液压举升装置在海上平台进行侧钻作业的可行性进行了分析。通过对渤海油田海上平台使用修井机进行侧钻作业的井统计分析，发现典型340K液压举升装置的作业能力能够满足修井机单一井眼侧钻90%以上已钻井对设备能力的需求；通过对设备的抗风载能力进行计算，发现在最大风力载荷、最大举升载荷及最大作业扭矩综合工况下，设备的强度及变形量都能满足标准要求，结果表明液压举升装置可应用于海上平台进行侧钻作业。     

海上平台监控系统分析研究

油气作为国家的战略资源,在国民经济中占有重要的地位。我国浅海大陆架拥有丰富的石油天然气资源,这部分资源尚处于初期开发阶段。新建海上采油平台采用无人值守的采油模式,该模式拥有国内外其它海上油田采油模式所不可比拟的优点。本文着重讲述了无人值守采油平台无线监控方案的论证及研究,并对设计开发的系统进行了描述,最后分析了该系统的可靠性。     

基于模糊理论的输电线路覆冰状态评估模型研究

架空输电线路的覆冰情况对电力系统的安全稳定运行带来了巨大危害,为了能准确评估输电线路覆冰状态,文章根据影响覆冰的多种条件和不确定性,提出了以输电线路在线监测系统为基础,综合分析环境温度、环境湿度、风速及覆冰厚度各种状态评估特征量,创建了基于模糊原理的输电线路覆冰状态评估方法。再根据经验和试验数据确定了模糊隶属度函数,建立了各状态评估的模糊推理规则库。最后结合现场监测试验结果能较好地评估当前输电线路和覆冰的综合状态,评估结果合理并对架空输电线路运行维护有指导意义。     

海上采油平台溢油风险分析及防控建议

针对海上采油平台溢油风险源众多、溢油事故防控重点不明确的现状,在以前溢油风险分析成果的基础上,对海上采油平台采油工艺进行理论分析和实地调研,确定出海上采油平台的溢油高风险设备设施及导致溢油事故的具体原因。并针对开排罐、火炬分液罐、舷外管线、输油软管断裂、海管泄漏造成溢油事故的风险提出防控措施,以提高海上采油平台溢油防控水平,进一步降低海上采油平台溢油事故风险。     

海上油气田输气海管防水合物冻堵探究

海洋石油开采是一项高风险、高投入、高回报的行业。采油平台作为海上油气资源开采的一线载体,承担着日常生产的重要任务。科学合理的对油田生产设备进行管理与维护,是日常工作的重中之重。文章结合海上采油平台一线生产实际,对如何加强输气海管的管理做进一步的探讨和分析。     

输气管道内腐蚀缺陷剩余强度评估方法分析

输气管道内腐蚀缺陷剩余强度的计算问题,归根结底是一个腐蚀管道力学失效问题。对含有内腐蚀缺陷的输气管道进行剩余强度计算是对整条管道进行安全评估极其重要的一环,对保证管道的安全平稳运行有着不可替代的作用。在对比分析几种常用管道剩余强度评估方法的基础之上,采用剩余强度评价保守性最好的DNV RP-F101标准为依托,编制输气管道内腐蚀缺陷剩余强度评估计算程序,工程实例证明了该评估程序的实用性和有效性。     

基于极值载荷的平台寿命模型

基于现役平台安全评估的需要,提出了基于极值载荷的平台寿命模型来描述结构承载能力与环境载荷的交互作用。给出了确定性模型与可靠性模型两种计算模型,并导出了相应的计算表达式。     

Divergent patterns of engagement in Internet standardization: Japan,Korea and China

This article analyzes the engagement of Japanese, Korean and Chinese participants in the development of Internet standards at IETF on the basis of four quantitative metrics: attendance, patenting, authorship and leadership. The results are strikingly divergent. Japanese involvement in Internet standardization began early and Japan was, for many years, second only to the U.S. in terms of IETF participation. Though Japanese participation has declined since the early 2000s, Japan remains a major contributor to IETF standardization. Korean involvement in IETF has always been significant, but below the levels of Japan and major European countries. Korean participation in IETF has also declined over the past decade, and has been dominated by one firm, Samsung. Though meaningful Chinese involvement in IETF did not begin until the mid-2000s, it has rapidly expanded in recent years. Today, China is a major player in numerous areas of Internet standardization in terms of three metrics (participation, patenting and leadership), and is rapidly gaining in terms of document authorship as well. Most of China׳s recent IETF involvement can be attributed to Huawei, though other Chinese firms have recently begun to increase their participation in the organization. Thus, contrary to some views that China׳s engagement with standardization is primarily one of indigenous innovation and “catching up”, China׳s experience with IETF demonstrates deliberate and effective engagement with a major Western standards-development organization on its own terms.     

增强Linux系统安全性的措施

L inux系统的安全取决于系统管理员如何来管理它。本文探讨了一系列可以增强安全性的技巧与策略 ,包括 :系统安装原则、BIOS安全、口令安全策略、设计帐户自动注销功能、文件系统和日志安全策略、使用 SSH及 TCP-WRAPPERS,隐藏系统信息、删除所有特殊帐户、关闭控制台程序、限制系统中的 SUID/ SGID程序等。本文最后向 L inux系统管理员提出了一些安全管理方面的建议     

快速成形技术的应用及热点分析

基于快速成形技术的原理,展示了快速成形技术在快速模具制造、金属零件直接成形、反求工程等领域的广泛应用,总结了快速成形制造技术研究的热点,即研发新材料和新设备、提高成形精度、建立RPM的反求工程系统、建立成形技术的统一标准和扩大成形技术的应用领域。     

Whose Image is it Anyway?: Some Considerations of the Curricular Importance of Subject Image in Secondary School Design and Technology Education

This paper explores the idea that a sense of school subject image is a necessary feature of curriculum management and a potent force for change. The discussion centres on the view that all school subjects have an image and that if those intimately involved with the subject do not control the image then someone else does! In such circumstances the image is the product of past encounters and old euphemisms and is unlikely to hold the changed realities.The UK developments in Design and Technology education (the term Design and Technology is used to denote the school subject defined under this heading by the UK National Curriculum, 1995) have created something of an image problem which has interesting international parallels. Some of these problems are due to clearly discernible internal tensions and an ambiguous relationship with other subject areas.Through greater attention to subject image internal controversies might be acknowledged and resolved, relationships with other subject areas can be more meaningfully understood and practitioners can be helped to make sense of curriculum change.     

CIS与现代企业管理美学

概括性介绍了 ＣＩＳ（Ｃｏｒｐｏｒａｔｅ Ｉｄｅｎｔｉｔｙ Ｓｙｓｔｅｍ）的三大基本组成，并阐述了它与现代企业管理密不可分的相互联系及所处的举足轻重的地位，指出导入ＣＩＳ是现代企业谋求发展的重要手段。     

HSE走进中国石油

企业管理水平的好坏直接影响着企业的经济效益,运用HSE管理能提高企业管理水平,HSE管理模式将健康,安全,环境三者视为一个有机的整体。HSE管理认为人的安全是第一位的,人是创造财富的原动力,是企业的最大财产,HSE管理体系强调的是“蝴蝶效应”。     

Material power and normative conflict in global and local agrifood governance: The lessons of ‘Golden Rice’ in India

This special section aims to investigate the interaction of global and local forces in shaping agrifood governance. It starts from the recognition that a multitude of actors and norms shape today’s agrifood system. The resulting opaqueness of the systems makes it extremely difficult to understand and explain processes and outcomes of agrifood governance. Given the sustainability challenges facing the agrifood system, improvements in our understanding of what the interaction of global and local actors and norms means on the ground are urgently needed, however. The section, therefore, analyses agrifood governance in India across a selected group of cases. It does so by employing a systematic framework emphasizing the material and ideational dimensions of power and their interaction. The section has chosen India as the setting in which to analyze this interaction due to the crucial role the food demand and supply of this rising power plays in today’s agrifood system. This article provides the special sections’ analytical framework, which uses the interplay of material and ideational dimensions of power as a focal lens. In addition, the article applies this framework to an empirical study of the political conflict around GMO foods in India, specifically the case of ‘Golden Rice’.     

Diffusion and usage of public e-services in Europe: An assessment of country level indicators and drivers

We analyze the state of the art of indicators on e-government, e-health, e-procurement and e-participation. We survey the main methodological properties of these indicators, and highlight their heuristic potential. Further, we address empirically the issue of the explanation of the availability scores, i.e. how the supply of the various e-services in each country is affected by political, institutional and socio-economic differences, and is followed by actual usage. The econometric analysis uncovers the importance of broadband penetration and higher education as drivers for most of the types of e-services and users (citizens and businesses). Moreover, a corruption-free and agile public sector proves to be an important pre-condition for more effective supply and usage. Despite data limitations and the complexity of the underlying diffusion phenomena, our study is the first truly longitudinal contribution aimed at disentangling the common drivers of such an important phenomenon – the e-services availability and usage across European countries. As such, this work appears useful to inform the policy debate and practice, in a phase characterized by a prospective reorientation of the public e-services provision and policy agenda.     

一种高精度的频率标准比对系统

频率标准源可以提供精确的标准频率,在测定频率标准源的各项性能指标时,要求测试系统必须具有很高的比对精度。所设计的频率标准比对系统采取多级倍频 混频方式使频率偏差逐级扩大后再测量,从而避免了直接进行高次倍频的困难,提高了测量精度,可以对高精度的频率标准的准确度、长短期频率稳定度进行快速测量,是一种高精度时畴参数测量系统。     

蒸汽热量计量应用的探析

研究了石油化工企业的燕汽计量情况,着重对蒸汽热量计量的合理性进行了分析,阐述了蒸汽热量计量的依据及计算方法,以及蒸气热量计量对节能降耗的重要意义.