This study investigates how EFL learner error patterns and frequencies differ in writing depending on students' language proficiency levels. A total of 152 Korean EFL students' essays were examined. The writing samples were first scored holistically on an impressionistic basis; then, based on the scores, the samples were grouped into low- and high-proficiency groups. The study identified 13 errors based on prevalence and significance. The study calculated the frequency of each error type committed by each group and compared the results using t-tests. A survey of English teachers was also conducted (N=32) to rate the gravity of each error and to compare the error gravity produced by each group. The result showed that low-proficiency group produced errors much more frequently, and the errors were more serious ones with high error gravity. The errors committed by the high-proficiency group were usually complex ones and occurred in more complicated contexts. The study also found that the errors with less gravity occurred more frequently in both groups and that they tended to be more persistent. The study indicated that although the students were aware of significance of errors, correcting the errors was beyond their current English capability.

We present two large cosmological N-body simulations, called Horizon Run 2 (HR2) and Horizon Run 3 (HR3), made using 60003 = 216 billions and 72103 = 374 billion particles, spanning a volume of (7.200 h-1Gpc)3 and (10.815 h-1Gpc)3, respectively. These simulations improve on our previous Horizon Run 1 (HR1) up to a factor of 4.4 in volume, and range from 2600 to over 8800 times the volume of the Millennium Run. In addition, they achieve a considerably finer mass resolution, down to 1.25 X 1011h-1M⊙, allowing to resolve galaxy-size halos with mean particle separations of 1.2h-1Mpc and 1.5h-1Mpc, respectively. We have measured the power spectrum, correlation function, mass function and basic halo properties with percent level accuracy, and verified that they correctly reproduce the CDM theoretical expectations, in excellent agreement with linear perturbation theory. Our unprecedentedly large-volume N-body simulations can be used for a variety of studies in cosmology and astrophysics, ranging from large-scale structure topology, baryon acoustic oscillations, dark energy and the characterization of the expansion history of the Universe, till galaxy formation science - in connection with the new SDSS-III. To this end, we made a total of 35 all-sky mock surveys along the past light cone out to z = 0.7 (8 from the HR2 and 27 from the HR3), to simulate the BOSS geometry. The simulations and mock surveys are already publicly available at http://astro.kias.re.kr/Horizon-Run23/.

This study investigates how wikis can promote EFL student writing by providing a real audience and authentic purposes for writing. The activity described in this paper is writing a narrative story on a wiki. Thirty-eight college students participated in this activity. During the activity the students constructed and negotiated meaning collaboratively. They posted a total of 153 versions and made 530 changes over four weeks. This study identifies the students' idiosyncratic writing and editing patterns that appeared on the wiki in the dimension of level, type, and purpose. The study employs both qualitative and quantitative data analysis for a more robust data analysis and triangulation of the data. The final product of the students' writing on the wiki exhibited that peer editing was effective in enhancing the quality of writing. While students viewed writing as a solitary and private activity in many EFL writing classrooms, the students in this study perceived writing as a social and communicative activity when engaged in the wiki writing activity.

This qualitative study explores how a holistic approach to writing across language skills can promote EFL student writing in terms of linguistic, cognitive, metacognitive, and affective factors. As an alternative to current writing methods that narrowly focus on the surface structure of language, this study shows how a technology-incorporated EFL writing project, conducted by Korean college students, integrated various activities across different language skills to support student writing globally and holistically. Beyond the traditional view of writing as a product and the current view of writing as a process, activities presented in this paper also embraced social factors of writing. This paper investigates the following three research questions: 1) how can an integrated curriculum facilitate student writing? 2) How can L1 writing assist L2 writing? 3) How can technology promote student view of writing as a social act? The result of this study indicated that the students’ writings greatly improved in both form and content during this project. The successful outcome of the Dokdo project will provide a new insight on EFL writing to writing teachers.