• Journal of The Korean Association For Science Education
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• v.21 no.5
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• pp.822-840
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• 2001

This article presents a theoretical model for conceptual change that relates cognitive conflict and the role of context. The model assumes that students derive alternative conceptions from everyday contexts while scientific concepts presume an idealized context, and hence, that the source of cognitive conflict results from the difference between the two contexts. Test results and analysis of the model are presented by applying it in a class studying the inertial motion of bodies. The subjects are 37 seventh grade boys.

• Journal of The Korean Association For Science Education
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• v.16 no.4
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• pp.340-350
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• 1996

Knowledge is composed through the interaction between the concept structure already held by students and their experience, and learning can be said to be the active process of solving the cognitive conflict caused by this interaction. Therefore, this study consists in showing the effective learning method and finding out the elements which the teacher has to own, through examining several forms of pre-conception or mis-conception of the inertia, the force-equilibrium, the action and reaction, the heat, and the electric current, and then finding out their solution and studying student's change in science concepts. For this study, the types of concept on the five above-mentioned materials which students have were examined through the concept-classifying question paper, and the classes to which the class mode for the change of concepts applied, were practised in each different classroom by each different instructor - a professor, a scientist, a teacher, and two students, respectively. And the effect of the teaching strategy based on these classes, and each different instructor' influence on the change of concept in students. were examined. The result of my study is as follows; 1. Students have various types of pre-conception which are different from science concept, and these types of pre-conception tend to last even after learning in class. 2. The thoughts on the correct science concept of the high school third-grade students who learned the physics in the traditional teaching method, and the second grade students who don't learn the physics yet, were nearly equal those of the second grade students by receiving the physics class through the cognitive conflict course were greatly changed especially that students showed the distinct change on mechanics and electric current. 3. Students didn't show the remarkable change of the science concept on the five materials in the four kinds of experimental classes by each different instructor but in the part of mechanics, there was the distinct change between the class by professor and those by the students. This was due to the difference of the authority and the attitude of the concept demonstrator. 1) The authority, the kind attitude, and the responsibility of the expert played an important role in the correct concept-formation of mechanics part - especially in the case of the mis-conception caused by the intuitive belief. 2) In the class by instructor with the democratic teaching method, the change of concept took place more easily, because in his class students could discuss the subject freely, so that they might experience the thought course to give them the confidence on the science concept.

• Proceedings of the Korean Society of Computer Information Conference
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• 2014.07a
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• pp.399-400
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• 2014

컴퓨터 프로그래밍 수업의 특성상 교수자가 평소 학습자들의 학습 수준 및 학습 이해도를 파악하는 것은 다음 수업을 준비하는데 있어서 매우 중요하다. 학습자들의 평소 학습 이해도를 파악하는 방법으로 형성평가가 가장 많이 이용되는데, 동일한 과목에도 형성평가 방법은 매우 다양할 수 있다. 본 연구에서는 다년간 컴퓨터 프로그래밍 수업에 적용해본 다양한 형태의 형성평가 방법들이 학습자들의 성적 변화에 어떤 영향을 미치는가를 분석해보았다. 그 결과 형성평가 수행 시기는 중간고사나 기말고사처럼 큰 시험을 앞둔 1~2주전과 같이 학습자들이 학습에 대한 필요성을 절실히 느낄 때 실시하는 것이 성적 상승에 더 긍정적인 영향을 주었고 평가방법으로는 프로그래밍 수업을 특성상 퀴즈와 프로그래밍 평가를 함께 실시하는 것이 성적 상승에 좋은 영향을 미쳤다.

• ETRI Journal
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• v.29 no.5
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• pp.688-690
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• 2007

This letter presents a filter for a car navigation system integrating a low-grade inertial measurements unit (IMU) and a global positioning system receiver. The filter is designed according to the state variables to be estimated and the usable measurements. The usable measurements change from case to case, and the estimative state variables also change due to the measurements; therefore, multiple models must be used for real environmental maneuvers. In this letter, four models for land navigation are chosen and switched by rearranging the system matrix and resetting the error covariance matrices.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.4
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• pp.42-47
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• 2003

Analysis of the elements affecting short circulation in highly integrated paper mills and identification of the interactions among these elements are very important tasks to prevent operational perturbations such as web breaks. In the present work a dynamic model for the short circulation is developed to analyze tuning methods for the outputs to follow set points during grade change operations. Steady state operation data are used to investigate dynamic characteristics of responses for input changes.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.13 no.1
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• pp.19-35
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• 2009

Objectives : In the study on the waveform analysis of radial artery pulse diagnosis, we need to establish fundamentals of contemporary pulse diagnosis research. To achieve certain experimental basis on traditional pulse diagnosis, we have to research the differences of pulse waveform according to pressure (in 5 level) and position (Chon, Gwan, Cheok in radial artery). As a first step, in present thesis, we tried to find the differences of pulse waveform according to pressure. Methods and Results : In this research, we analyzed seven parameters of the waveform at five levels of pressure. The parameters are E(so called 'energy', a representative of pulse strength), h1(height of percussion wave) and h2(height of subincisura). The results were as follows. 1. When we analyzed the change of the waveform according to pressure in the left Gwan, E, hl, h2 and A differed between 1st and 2nd grade, between 1st and 3rd grade, between 1st and 4th grade, between 1st and 5th grade, between 2nd and 3rd grade, between 2nd and 5th grade, between 3rd and 5th grade and between 4th and 5th grade in 95% confidence interval. 2. And t2, t4 differed between 1st and 2nd grade, between 1st and 5th grade, between 2nd and 4th grade, between 2nd and 4th grade, between 2nd and 5th grade, between 3rd and 4th grade, between 3rd and 5th grade and between 4th and 5th grade in 95% confidence interval. 3. W differed between 1st and 3rd grade, between 1st and 4th grade, between 2nd and 3rd grade, between 2nd and 4th grade, between 2nd and 5th grade, between 3rd and 4th grade, between 3rd and 5th grade, and between 4th and 5th grade in 95% confidence interval. 4. And h2/h1 differed between 1st and 4th grade, between 1st and 5th grade, between 2nd and 4th grade, between 2nd and 5th grade, between 3rd and 4th grade & between 3rd and 5th grade in 95% confidence interval. 5. There were differences between 1st and 2nd grade & between 2nd and 5th grade in the case of t4/t2 in 95% confidence interval. And there were differences between 1st and 5th grade, between 3rd and 4th grade, between 3rd and 5th grade & between 4th and 5th grade in the case of W/A in 95% confidence interval. And were differences between 1st and 2nd grade, between 2nd and 3rd grade, between 2nd and 4th grade, between 3rd and 4th grade, between 3rd and 5th grade & between 4th and 5th grade in the case of A/E in 95% confidence interval. Conclusions : As mentioned above, we conclude that the waveform analysis according to five grade pressure in the left Gwan shows the difference of waveform in each grade pressure.

• BMB Reports
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• v.46 no.5
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• pp.244-251
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• 2013

Lignocellulosic materials are commonly used in bio-$H_2$ production for the sustainable energy resource development as they are abundant, cheap, renewable and highly biodegradable. In the process of the bio-$H_2$ production, the pretreated lignocellulosic materials are firstly converted to monosaccharides by enzymolysis and then to $H_2$ by fermentation. Since the structures of lignocellulosic materials are rather complex, the hydrolysates vary with the used materials. Even using the same lignocellulosic materials, the hydrolysates also change with different pretreatment methods. It has been shown that the appropriate hydrolysate compositions can dramatically improve the biological activities and bio-$H_2$ production performances. Over the past decades, hydrolysis with respect to different lignocellulosic materials and pretreatments has been widely investigated. Besides, effects of the hydrolysates on the biohydrogen yields have also been examined. In this review, recent studies on hydrolysis as well as their effects on the biohydrogen production performance are summarized.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.5
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• pp.61-79
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• 2018

The purpose of this study is to investigate the flora of Sohyeoncheon which is planned for ecological restoration and river maintenance from upstream to downstream, and also to collect the ecological data to cope with the change of the ecosystem of Sohyeoncheon. The numbers of vascular plants were summarized as 336 taxa including 82 families, 233 genera, 298 species, 1 subspecies, 33 varieties and 4 forms. The rare plants were 3 taxa including Aristolochia contorta Bunge, Prunus yedoensis Matsum.(planting) and Koelreuteria paniculata Laxmann. The Korean endemic plants were 4 taxa including Populus tomentiglandulosa T.B.Lee(planting), Lespedeza maritima Nakai, Forsythia koreana (Rehder) Nakai(planting) and Weigela subsessilis (Nakai) L.H.Bailey. The specific plants by floristic region were 15 taxa including 1 taxon of grade V, grade IV and grade II each, 4 taxa of grade III and 8 taxa of grade I. The naturalized plants were 60 taxa and the invasive alien plants were 3 taxa. The results of analysis by vertical structures showed that naturalized plants included 31 taxa of upstream, 53 taxa of midstream and 38 taxa of downstream. An analysis of crossing structures showed that 2 taxa of water channel, 3 taxa of low waterside, 41 taxa of high waterside and 48 taxa of bank.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.3
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• pp.71-91
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• 2016

The purpose of this study is to offer the raw data for conservation of natural resources by surveying the flora distributed in Juwangsan National Park. The numbers of flora were summarized as 575 taxa; 99 families, 333 genera, 507 species, 4 subspecies, 56 varieties and 8 forms. The threatened species was Eleutherococcus senticosus, and the rare plants were 17 taxa; Anaphalis sinica, Jeffersonia dubia, Hylotelephium ussuriense, Berchemia berchemiaefolia and so forth. The Korean endemic plants were 13 taxa; Salix pseudolasiogyne, Carpinus laxiflora, Pseudostellaria coreana, Thalictrum actaefolium var. brevistylum, Corydalis albipetala and so forth. The specific plants by floristic region were 69 taxa; 31 taxa of grade I, 16 taxa of grade II, 8 taxa of grade III, 7 taxa of grade IV and 7 taxa of grade V. The naturalized plants were 27 taxa; Fallopia dumetorum, Rumex crispus, Chenopoidum album, Amaranthus patulus, Lepidium apetalum and so forth, and the invasive alien plants were Ambrosia artemisiifolia and Aster pilosus. The target plants adaptable to climate change were 18 taxa; Anemone reflexa, Eranthis stellata, Hylomecon vernalis, Lathyrus vaniotii and so forth. The plants with approval for delivering oversea were 31 taxa; Dianthus longicalyx, Thalictrum ichangense, Spiraea blumei, Glycine soja and so forth.

• Journal of Korean Clinical Nursing Research
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• v.16 no.1
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• pp.95-105
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• 2010

Purpose: The purpose of this study was to examine the difference between direct and indirect nursing activity times according to the grade of nursing management fee. Methods: The subjects of this study were 324 working nurses at the time of 3rd grade and 319 working nurses at the 2nd grade of nursing management fee in one university hospital. Nursing activity time was measured in April and May, and in September and October of 2008 for comparison. The data were analyzed by SPSS win using frequency and t-test. Results: Direct nursing care activity time per one patient was significantly higher at 2nd grade than 3rd grade in day shift (t=-2.55, p=.012). Direct nursing care workload per one nurse was significantly lower at 2nd grade than 3rd grade in evening shift (t=2.21, p=.030), whereas indirect nursing care workload was lower at 2nd level in night shift (t=2.43 p=.016). Conclusion: The findings from this study showed that higher nurse-to-patient ratio can provide greater amount of direct nursing care activity for the patient. Also, it decreased workload of nurses. The higher nurse-to-patient ratio will be beneficial for promoting quality of nursing care as well as decreasing nurse's heavy workload.