• Journal of the Korean earth science society
• /
• v.32 no.1
• /
• pp.84-98
• /
• 2011

The study investigated the linguistic characteristics of middle school students' writing on the themes of earth science through analysis of its genre and register. Data for analysis included $7^{th}$ grade and $9^{th}$ grade students' writings about 'global warming' and 'classification of rocks'. The results of this study include: First, many students were not accustomed to writing in genre, especially exposition genre. Second, in terms of ideational meaning, the material verbs representing action or doing were more dominant than relational verbs that are related to the attribute or definition of things, and additional logical relations were predominant. Third, regarding interpersonal meaning, agents, emotions, subjective opinions appeared in the writings and students did not express their ideas conclusively and revealed feelings of doubt and uncertainty about their knowledge. Fourth, as for textual meaning, most students listed fragments of information using additional conjunctions in simple structures and were not accustomed to writing texts with organizing structures, logical patterns, cohesion, and coherence. From these results, we argued that the scientific writings should be emphasized in science learning that aims to foster scientific literacy. In addition, we discussed the necessity of improving science teachers' perceptions on scientific writing as well as setting up a specific plan in the national curriculum.

• Journal of Space Technology and Applications
• /
• v.3 no.2
• /
• pp.118-143
• /
• 2023

Space is becoming more commercialized. Despite of its delayed start-up, space activities in Korea are attracting more nation-wide supports from both investors and government. May 25, 2023, KSLV II, also called Nuri, successfully transported, and inserted seven satellites to a sun-synchronous orbit of 550 km altitude. However, Starlink has over 4,000 satellites around this altitude for its commercial activities. Hence, it is necessary for us to constantly monitor the collision risks of these satellites against resident space objects including Starlink. Here we report a quantitative research output regarding the conjunctions, particularly between the Nuri satellites and Starlink. Our calculation shows that, on average, three times everyday, the Nuri satellites encounter Starlink within 1 km distance with the probability of collision higher than 1.0E-5. A comparative study with KOMPSAT-5, also called Arirang-5, shows that its distance of closest approach distribution significantly differs from those of Nuri satellites. We also report a quantitative analysis of collision-avoiding maneuver cost of Starlink satellites and a strategy for Korea, being a delayed starter, to speed up to position itself in the space leading countries. We used the AstroOne program for analyses and compared its output with that of Socrates Plus of Celestrak. The two line element data was used for computation.