Abstract. This paper consists of a review of the important contributions of four COST (European Co-operation in Science and Technology) Actions in the period 1991–2009 to terrestrial ionospheric research, with applications in modern communication and navigation systems. Within this context, new ionospheric studies were initiated, leading to the development of a number of models, algorithms for prediction, forecasting, and real-time specification, as well as numerical programs. These were successfully implemented in different collaborative projects within EU instruments, promoting co-operation between scientists and researchers across Europe. A further outcome was to bring together more than a hundred researchers from around 40 scientific institutions, agencies, and academia in about 25 countries worldwide. They collaborated with enthusiasm in research, as briefly described in this paper, forming a lively ionospheric community and presenting a strong intellectual response to the rapidly growing contemporary challenge of space weather research.

中文翻译：

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在两千年之间的过渡中，COST行动在统一欧洲电离层社区中的作用

摘要。本文包括对1991-2009年间的四个COST（欧洲科学技术合作）行动对地面电离层研究的重要贡献及其在现代通信和导航系统中的应用的回顾。在此背景下，开始了新的电离层研究，从而导致开发了许多模型，预测，预报和实时规范算法以及数值程序。这些措施已成功地在欧盟文书内的不同合作项目中实施，从而促进了欧洲科学家与研究人员之间的合作。进一步的成果是将来自全球约25个国家/地区的40多家科研机构，机构和学术界的100多名研究人员聚集在一起。