共查询到20条相似文献，搜索用时 57 毫秒
1.
随着工业发展的高速进行,我国内陆石油资源日渐枯竭,多数石油相关的下游企业高度依赖进口。我国有着丰富的海洋石油矿藏,海洋油气资源的开发直接关系到相关产业的进一步发展,影响着我国能源、经济安全的稳定。随着海洋石油作业从大陆架逐渐向着深海延伸,海洋石油钻井平台作为海洋石油资源开发的主要设备,钻探平台技术和设备升级势在必行。本文将对我国现有石油钻井平台技术和设备与国外先进技术进行比较,为未来我国石油钻井平台技术和设备的发展提供一些可供参考的意见和建议。 相似文献
2.
自升式移动海洋石油平台的拖航是海洋石油作业中比较普遍的作业之一,拖航作业要考虑的安全因素很多,通过对拖航过程中每个步骤存在的风险进行分析、控制,制定拖航计划和应急措施,从而更好地组织拖航作业的安全、有序进行。 相似文献
3.
为了确保海洋平台在设计使用寿命期内能够安全可靠的进行油气资源的钻采工作,钢结构平台制造过程中的质量管理和质量控制就显得格外重要.本文理论联系实际,对海洋石油工程运用钢结构平台质量管理问题进行了探究. 相似文献
4.
5.
6.
随着我国国民经济的快速发展,石油的需求量在逐渐增加,全球的油气储量呈快速递减趋势,陆地的石油储存量有限,而拥有全球面积70％的海洋拥有着大量的油气资源,由此人们加快了对海洋石油的开采.在海洋石油开采中海上石油平台电力系统是海洋石油开采作业中的一个重要组成部分,它为整个资源开采过程提供必需的能源和动力.通过对电力系统的全面监控和有效的管理方能保证电力系统的安全运行,保证海上石油的顺利开采.发电机是电力系统中最重要的电力设备,发电机的安全运行影响着整个电力系统,因此合理的继电保护装置不仅能够保证各种继电设备的有机协调并发挥其作用,还能够提高电力系统的安全可靠性,降低因电力系统引发的损失. 相似文献
7.
8.
海洋石油开发环境的恶劣、大浪、海流、潮汐等因素容易造成海底管线破损和管线的提前老化腐蚀,再者海洋平台附近施工作业船只来往比较密集,容易发生钩挂碰砸等事故,造成原油泄漏极易威胁海洋环境。本文主要分析目前海上平台海底管道的施工对海洋造成哪些影响,及生产过程中可能对海洋环境造成污染的事件进行分析,针对发生的高风险情况,提供减少或避免事故发生的建议。 相似文献
9.
10.
11.
A research group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol-a chemical found in the skins of red grapes in red wine-can improve the sensitivity of mice to the hormone insulin according to a report in the October issue of Cell Metabolism.…… 《中国科学院院刊(英文版)》2008,22(1):14-15
Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said. 相似文献
12.
《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
13.
Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
14.
《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
15.
A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
16.
Active biological molecules functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery disease diagnosis therapy new nanodevice construction.…… 《中国科学院院刊(英文版)》2008,22(1):22-22
Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction. 相似文献
17.
Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
18.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
19.
Leah A. Lievrouw 《The Information Society》2000,16(2):155-159
This essay focuses on universal service and the Internet as means to support social and political participation. The emphasis on access to telecommunications systems in conventional approaches to universal service is contrasted with access to content. A model of the information environment is described that accounts for the roles of content and conduit, both of which are necessary conditions to achieve true access. A method is outlined for employing information indicators to observe or measure the information environment. 相似文献
20.
Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献