• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.11
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• pp.1176-1181
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• 2004

In high-capacity disk drives with ever-growing track density, the allowable level of position error signal(PES) is becoming smaller and smaller. In order to achieve the high TPI(track per inch) disk drive, it is necessary to improve the writing accuracy during the servo track writing(STW) Process through the reduction of track mis-registration sources. Among the main contributors of the non-repeatable runout(NRRO) PES, the disk vibration and the head-stack assembly vibration is considered to be one of the most significant factors. Also the most contributors of repeatable runout(RRO) come from the contributors of NRRO which is written-in at the time of STW process. In this paper, the effect of NRRO on servo written-in RRO is Investigated by experimentally, and the experimental result shows that the written-in RRO can be effectively reduced through a STW process under low dense medium condition such as semi-vacuum.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.6
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• pp.79-86
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• 1999

We propose a new photorefractive demultiplexer(DMUX) for WDM communicaytion system using a wavelength selectivity and demultiplexing properties of a volume holographic grating filters formed in $LinbO_3$ crystal doped with 0.015wt.% Fe. The wavelength selectivity properties of the filter are analyzed and experimentally investigated as a function of the following parameters : the crossing angle of the two writing beams, the reading-beam angle and writing-beam size. In addition, applying these wavelength selectivity properties and the multiplexing technique for recording multiple-exposure filters with equal diffraction efficiency, some preliminary experimental results are presented for use as DMUX.

• Journal of the Korean Chemical Society
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• v.56 no.4
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• pp.500-508
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• 2012

The purpose of this study was to investigate the impact of multimodal representation-based lesson on embeddedness of multimodal representation in high school students' writing. The participants in this study were two groups of second-year science-track students (74 students) at an academic high school in a metropolitan city. One group (41 students) was assigned to the experimental group, the other group (33 students) was assigned to the comparative group. Data analysis showed that the students of the experimental group were better at utilizing and embedding multimodal representations. Thus, the conclusion was drawn that multimodal representation-based lesson had an effect on high school students' embeddedness of multimodal representation.

• Journal of English Language & Literature
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• v.56 no.6
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• pp.1119-1133
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• 2010

This paper explores Myung Mi Kim's poetics of the archive in Commons. Commons begins with a gesture that critiques a prior act of archivization: "Here, this speck and this speck that you missed." As the poems accrue in the book, Commons demonstrates the desire to record those experiences that have been neglected by the architects of traditional archives while at the same time interrogating the very logic of the archive. Crucial to that interrogation is the poetic form. Kim's attempt to archive silences and gaps leads to a radical experiment with form and language. It reformulates the archive as an open system amenable to interruption, extension, and revision. I examine in detail the techniques that contribute to her poetics of the archive, a poetics that draws the readers out of the narrow confines of their personal experiences and their political identities. By juxtaposing Kim's poems with her statements of poetics given as interviews, this paper connects the project of Commons to Kim's larger concern with open form and experimental writing. I argue that the "difficulty" of her poetry should be reinterpreted as a demand that her text makes on the readers to broaden their terms of engagement. The linguistic experiment of Commons provides an occasion to rethink the habitual ways in which time is experienced, national histories are written, and literary works are consumed.

• Journal of The Korean Association For Science Education
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• v.33 no.7
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• pp.1259-1272
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• 2013

The purpose of this study was to investigate the effects of Science Writing Heuristic (SWH) laboratory class on the creative thinking and critical thinking of middle school students. Science writing heuristic programs were developed based on SWH strategies developed by Keys et al (1999). This study was conducted on 63 students from two classes as the comparative group and 63 students from two other classes as the experimental group. The cognitive level of the group as a homogeneous group was similar, and the program was applied to a total of 18 periods based on nine topics from March to July 2011. Evaluation instruments used in pre-test and post-test were the creative and critical thinking tests. To consider the score for creative and critical thinking. the SPSS 20.0 program was used. The study made use of technical statistics and ANCOVA. The result of this study showed that creative problem solving skills were improved by SWH in laboratory class. Therefore, persistent presentation of SWH teaching strategies and developing various experiment topics are required.

• Korean Journal of Cognitive Science
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• v.3 no.2
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• pp.271-289
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• 1992

In this paper,a cursive on-line Hangul recognition system which permits cursive writing between graphemes is presented.In general,the recognition of cursive Hangul writing has a difficulty of graheme segmentation and a complexity in matching procedure due to the increasing number of character candidates.To manage efficiently these problems,we propose a double segmentation method.Based on this segmentation,a recognition algorithm based on the line segment matching is proposed.Through the experimental result,it is show that the proposed recognition method is suitable for the cursive Hangul writings.

• Journal of Korean Elementary Science Education
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• v.24 no.5
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• pp.487-494
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• 2005

The purpose of study was to introduce and propagate the children's verses as the teaching/learning strategies in science education far elementary students and teachers. 238 pre-service teachers, 140 in-service teachers and 602 elementary students wrote the own verses and read colleague's verses with respect to science. In this situation, the writing was considered as creation and the reading was reception and appreciation for the verses. When they wrote the verses, the themes were not restricted except that they were related to science. Mostly, the subjects were something about science concepts, scientific phenomena or experimental instruments, etc. In addition, this study investigated the merits and demerits of the reading/writing activities of children's verses as the teaching/learning strategies in science classroom.

• English Language & Literature Teaching
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• v.15 no.2
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• pp.151-168
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• 2009

The present study investigates the impact of trained peer feedback on the quantity and quality of revisions made by EFL students at a low-intermediate level. Peer review training was carried out in experimental group through four in-class training sessions and four peer dyad-instructor conferences after class. Students' $1^{st}$ drafts with written peer feedback and revised drafts prior to and post training were collected and analyzed. Results reveal that after training the students produced more revisions in response to their peer comments (96% of total revisions) and those revisions were counted as enhanced in quality (93% of peer-triggered revisions). In contrast, the results of paired t-test within control group indicate that there was no significant difference between two data collected from week 3 and week 16 (t = -.57, df =19, p = .577 at p < .05). The findings suggest that training as an ongoing process of teacher intervention contributes to effectiveness of the peer feedback activity. The study provides pedagogical implications for how to structure and implement peer review training for the sake of its direct strength in an EFL writing class.

• Korean Journal of Optics and Photonics
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• v.8 no.3
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• pp.241-244
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• 1997

A speckle pattern from an optical fiber is used for a reference beam in writing and reading a volume hologram. The photorefractive volume hologram with this scheme shows good spatial selectivity for spatial(shift) multiplexing because the speckle pattern in writing and reading a hologram looses correlation with a small spatial shift. This scheme has the insensitivity to axial movement. The data storage system with this scheme will have a high storage density and a good stability in operation. We theoretically analyze the diffracted beam from a volume hologram recorded with the speckle pattern from the optical fiber. Experimental results are presented and compared with numerical analysis.

• Journal of The Korean Association For Science Education
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• v.31 no.2
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• pp.198-209
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• 2011

In this study, pre-service science teachers' reflective thinking in their journal writing was investigated. To do this, the authors used pre-service science teachers' journal writing abilities, wherein they not only reported data and result formally, but also wrote their feelings and reflections about an inquiry-based physics experiment they performed. Pre-service science teachers' writings were decomposed into sentences and each sentence was analyzed into a framework with 4 dimensions: knowledge, procedure, orientation and attitude. Reflective thinking in knowledge dimension included reflection on what they know before the experiment, what they still do not know and what they learned from the experiment. Reflective thinking in procedure dimension included recalls of experiences about general experimental procedures and specific experimental skill. Reflective thinking in orientation dimension included their views about the nature of science and science teaching and learning, and reflective thinking in attitude dimension consisted of interests, motives and values about the experiment they performed. While there were some variations in frequency distribution of reflective thinking by the topic of experiments, pre-service science teachers' reflective thinking in journal writings revealed their metacognition on their knowledge and learning, epistemological belief about science and science learning, and affective domain related to experiment. This study can infer that such kind of writing with 'their own language' in an informal way followed by formal 'scientific' reports in a scientific experiment has a significance not only as a mediator representing reflective thinking but also as an instructional activity to facilitate reflective thinking in science learning and teaching.