간행물
한국지구과학회지 KCI 등재 The Journal of The Korean Earth Science Society
- 발행기관 한국지구과학회
- 자료유형 학술지
- 간기 격월간
- ISSN 1225-6692 (Print)2287-4518 (Online)
- 수록기간 1979 ~ 2024
- 주제분류 자연과학 > 지구과학 자연과학 분류의 다른 간행물
- 십진분류KDC 450DDC 550
권호리스트/논문검색
제34권 제5호 (2013년 9월) 7건
1.
2013.09
구독 인증기관 무료, 개인회원 유료
Socheong island is a unique island containing Precambrian stromatolites in South Korea. Most of Socheong stromatolites are domes and columns, occurring as 10 cm to 1 m thick stromatolite beds. Lower parts of the stromatolite beds are predominantly composed of domes, but columns increase toward the upper level of stromatolite beds. In many of the stromatolite beds, inclined columns are easily identifiable, which is generally considered as a result of heliotropism. From general lithology, sedimentary structures, inclined angles and distributional pattern, and structural deformation of sedimentary rocks of Socheong island, the inclination of Socheong stromatolites could be better interpreted as a secondary structural deformation probably after formation of stromatolite columns, rather than as a result of heliotropism. However, at this moment, we do not clearly reject heliotropism interpretation for inclined columns of Socheong stromatolites. This is because the original position of stromatolite columns could have been lost if structural deformation had affected the whole sedimentary rocks of Socheong island.
4,300원
2.
2013.09
구독 인증기관 무료, 개인회원 유료
Spherical harmonics power spectrum of the geopotential field of Gaussian-bell type on the sphere was investigated using integral formula that is associated with Legendre polynomials. The geopotential field of Gaussian-bell type is defined as a function of sine of angular distance from the bell's center in order to guarantee the continuity on the global domain. Since the integral-formula associated with the Legendre polynomials was represented with infinite series of polynomial, an estimation method was developed to make the procedure computationally efficient while preserving the accuracy. The spherical harmonics power spectrum was shown to vary significantly depending on the scale parameter of the Gaussian bell. Due to the accurate procedure of the new method, the power (degree variance) spanning over orders that were far higher than machine roundoff was well explored. When the scale parameter (or width) of the Gaussian bell is large, the spectrum drops sharply with the total wavenumber. On the other hand, in case of small scale parameter the spectrum tends to be flat, showing very slow decaying with the total wavenumber. The accuracy of the new method was compared with theoretical values for various scale parameters. The new method was found advantageous over discrete numerical methods, such as Gaussian quadrature and Fourier method, in that it can produce the power spectrum with accuracy and computational efficiency for all range of total wavenumber. The results of present study help to determine the allowable maximum scale parameter of the geopotential field when a Gaussian-bell type is adopted as a localized function.
4,000원
3.
2013.09
구독 인증기관 무료, 개인회원 유료
Since 1984, the author has been studying the Daedong flora and has collected a large number of fossil plants from the Amisan Formation of Nampo Group distributed in Chungnam Coal-Field. One of the fossil plants was bennettitalean male flower, which was collected in 1986. The author described it as Weltrichia sp. The occurrence of Weltrichia sp. is the first record in the Early Mesozoic Daedong flora of Korea.
4,000원
4.
2013.09
구독 인증기관 무료, 개인회원 유료
This study presents the global star formation efficiency (SFE) of 272 local star-forming galaxies based on the HI gas mass, stellar mass, star formation rate (SFR), and morphology. The SFE increases as the stellar mass increases while the specific SFR decreases. The SFE is enhanced for galaxies with large Há equivalent widths, which is primarily due to the large SFR, not due to the large available amount of gas. The SFE is also enhanced by a factor of ~2 for merging systems compared to the normal spirals, showing that the merger-induced high pressure and density environment are crucial for the active star formation. Based on the SFR scaling relation, I present a SFR calibration formula using the HI gas mass.
4,000원
5.
2013.09
구독 인증기관 무료, 개인회원 유료
We performed a BVR photometric survey for the entire Small Magellanic Cloud (~26 deg 2 ) with a mosaic system, Wide Field Imager (WFI), covering three seasons: September and October 2001 and November 2002. Through the usual data reduction procedures, we present ~0.73 million catalogue stars brighter than 19 magnitude in B amongst a total of ~1.3 million and compare them with published astrometry and photometry results. We found that the average differences between our and the published data are ~0.7 arcsec in astrometry and 0.065, 0.054, and 0.163 in B, V, and R, respectively, in photometry. In addition, using the 2dF spectroscopic data from Evans et al. (2004), we determined the color excesses in (B-V) and (V-R) to be 0.086±0.156, and 0.065±0.112, respectively, while for the distance modulus, we obtained 18.55±1.05.
4,500원
6.
2013.09
구독 인증기관 무료, 개인회원 유료
In this commentary, I examined the implications of Existentialism for science teaching and teacher education. Existentialist thoughts and premises can be used to explore the human element in an educational system. Before emphasizing the pragmatic and technical aspects of teaching, we need to rethink why we teach and recognize our learners as unique beings in a continual process of becoming. By incorporating the existential perspective into curriculums and pedagogies of science education, we can help learners to make their existences and experiences meaningful. This paper consists of three parts. In the first part, I drew on relevant aspects of Existentialism and its implications on the views of the learner. In the second part, I examined the competency-based curriculum in light of Existentialism. Existentialism aims, in part, to develop an educated person who possesses a clear sense of personal identity, a critical attitude, and the inclination to be a life-long learner, and so on. These characteristics are consistent with the implications developed from the competency-based curriculum. In the third part, I explored pedagogical activities consistent with existentialist thinking the ultimate goal of which is to create authentic individuals who can take responsibility for being humans. In the conclusion, I discussed how existentialist ways of thinking and teaching call for the science teacher's reflective practices, where the teacher needs to integrate personal and professional knowledge as the situation demands.
4,000원
7.
2013.09
구독 인증기관 무료, 개인회원 유료
The purpose of this study was to investigate the difference of teachers' interaction with their students when teaching science in New York (NY) and in Korea. As part of the 2011 Korean International Teacher Fellows (KITF), supported by the Ministry of Education, Science and Technology (MEST) and the National Institute for International Education Development (NIIED), Korean science teachers observed, for six months, New York's science classes in terms of how teachers interact with their students and how students learn science during science instruction. The participants were 10 science teachers in five middle and high schools that taught Physics, Chemistry, Biology, Earth Science, and Environment Science in NY. The National Board for Professional Teaching Standards (NBPTS, 2003) and Instruction as Interaction (Cohen et al., 2003) were used as an instrument to identify each teacher's teaching and classroom interaction. Several characteristics of science classes in NY were revealed, which are different from Korean science classes. First, science teachers in NY dominantly put more focus on their subject of teaching during science interaction while, Korean science teachers not only teach science but also do counseling to students as a homeroom teacher. Second, science teachers in NY acknowledged the students' individuality and have positive experiences of professional development supported by their school and district more than Korean science teachers do. Third, science teachers in NY sometimes showed limited knowledge about the concepts of science and lack of collaboration with other science teachers. This characteristics may prevent the school from strengthening its subject program and keeping equity across the grade levels and courses.
4,800원
