• Journal of the Korean Institute of Educational Facilities
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• v.10 no.3
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• pp.27-36
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• 2003

This paper aims to analyse facilities and characteristics of management for 21 model schools' open education system. So, we analyzed the class management and the methods of open education, teacher's mind, the shape and form of study group and we investigated teachers' satisfaction rate about the physical space. As a result, it is considered that the change for structure of learning space unit is needed because of the limitation in standard class size by the rule for construction. Considering the decrease of real using space by the space of learning materials or learning furniture, it should enlarge the structure of learning space unit or decrease the number of students. And to use multipurpose space practically as a place of study, it need that the multiple support of study program for teachers by government, support in course of study, giving training opportunity to teachers, distribution of personal management.

• Restorative Dentistry and Endodontics
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• v.18 no.2
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• pp.413-422
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• 1993

The purpose of this study was to evaluate the adaptation of light cured glass ionomer cement and composite resin using all- etch technique to tooth structure. In this study, class V cavities were prepared on the buccal surfaces of 10 extracted human premolar teeth with cementum margin and teeth were randomly assigned 2 groups of 5 teeth each. The cavities of glass ionomer cement group were filled with the light cured glass ionomer cement(Fuji II LC) and the cavities of composite resin group were filled with the light cured composite resion(P - 50) using all- etch technique with All- Bond 2. The restored teeth were stored in 100 % relative humidity at $37^{\circ}C$ for 48 hours. And then, the roots of the teeth were removed with the tapered fissure bur and the remaining crowns were sectioned occlusogingivally through the center of restorations. Adaptation at tooth - restoration interface were assessed occlusally, gingivally, and axially by scanning electron microscope. The results were as follows : 1. The adaptation to enamel walls of composite resin restorations using All - Bond 2 showed better than glass ionomer restorations. 2. The adaptation to gingival and axial walls of glass ionomer restorations showed better than composite resin restorations using All - Bond 2. 3. In both groups, occlusal margins of restorations showed better adaptation than gingival margins of restorations.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.9
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• pp.771-780
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• 2012

Naro-science satellite which will be launched by KSLV-1 has been successfully developed. Naro-science satellite is a 100kg-class small size science satellite whose structure is composed of one of a typical light and high strength aluminum honeycomb sandwich panel. In this research, dynamic responses of the satellite with respect to the design requirements were investigated by means of real experiments and numerical finite element analyses. The core technologies of the structure design and analysis about fracture and safety has been obtained through a wide range of analyses and tests. The results obtained in this study can be significantly utilized for the next generation satellite development.

• Journal of Environmental Science International
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• v.21 no.3
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• pp.313-326
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• 2012

Three embankments, namely Changpo, Bokkil and Guil, in Chunggye Bay were investigated to assess the influence of environmental changes to phytoplankton size structure, distribution of species and standing crops. Three stations was sampled near at each embankment in Nov. 2006, Feb. 2007, May 2007 and Aug. Phytoplankton were classified into net-size (>20${\mu}m$) and nano-size (<20${\mu}m$). In summer, the freshwater discharge seemed to have influence in the decrease of salinity and in the increase of turbidity, ammonium and phosphorus concentrations. Chl a concentration and phytoplankton abundance in Feb. 2007 were observed to be generally higher in all stations compared to other periods. Net-size phytoplankton was observed to be higher in Feb. 2007 and May 2007 compared to nano-sized phytoplankton. However, there was shift in phytoplankton composition in Nov. 2006 and Aug. 2007. Phytoplankton under seven class (Bacillariophyceae, Chlorophyceae, Chrysophyceae, Cryptophyceae, Cyanophyceae, Dinophyceae, Euglenophyceae) was identified during the study period. It was found out that the major phytoplankton class was Bacillariophyceae. Phytoplankton was more diverse in autumn compared to any other season. Cyanophyceae was increased in summer. In rainy season, change in physical factors (salinity, transparency) seemed to have more influence on phytoplankton growth compared to inorganic nutrients.

• Restorative Dentistry and Endodontics
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• v.42 no.3
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• pp.240-252
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• 2017

The restoration of endodontic tooth is always a challenge for the clinician, not only due to excessive loss of tooth structure but also invasion of the biological width due to large decayed lesions. In this paper, the 7 most common clinical scenarios in molars with class II lesions ever deeper were examined. This includes both the type of restoration (direct or indirect) and the management of the cavity margin, such as the need for deep margin elevation (DME) or crown lengthening. It is necessary to have the DME when the healthy tooth remnant is in the sulcus or at the epithelium level. For caries that reaches the connective tissue or the bone crest, crown lengthening is required. Endocrowns are a good treatment option in the endodontically treated tooth when the loss of structure is advanced.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.810-812
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• 2008

Previously study on structural design of the main wing of the twenty-seat class WIG(Wing in Ground Effect) craft. In the final design, three spars construction was selected for safety in the critical flight load, and the Carbon-Epoxy material was selected for lightness and structural stability. In this study, the forced vibration analysis was performed on the composite main wing structure of the twenty-seat class WIG craft with two-stroke pusher type reciprocating engine. The vibration analysis based on the finite element method was performed using a commercial FEM code, MSC/NASTRAN. Excitations for the frequency response analysis were assumed as the H-mode(horizontal mode), the V-mode(vertical mode) and the X-mode(twisted mode) which are typical main vibration modes of engine. And excitations for the transient response analysis were assumed as the L-mode(longitudinal mode) with the oscillating propeller thrust which occurs in operation. According to the result of forced vibration analysis, structural design was modified to reduce the vibrations.

• Journal of Korean Elementary Science Education
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• v.38 no.3
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• pp.387-394
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• 2019

The purpose of this study was to investigate the effects of writing science diary on science learning motivation, science academic achievement and ecological sensitivity of elementary students. Teaching unit was focused on 'The structure and function of plants' in 6th grade science text book. The subjects of study were 51 students of two classes. One class of 25 students, experimental group, wrote science diaries as homework. While the other class of 26 students, comparative group, performed homeworks with fill-in-the-blank worksheets. The results of this study can be summarized as follows: First, writing science diary had a meaningful effect on improvement of science learning motivation. Second, writing science diary had a meaningful effect on improvement of science academic achievement. Third, writing science diary had a meaningful effect on improvement of ecological sensitivity. And we could find that students had a favorable impression and high satisfaction level about writing science diary from the questionnaire.

• Journal of the Korean Society of Costume
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• v.35
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• pp.343-366
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• 1997

Most of the recently-exhumed excavat-ed costume is the garment for the dead which is one of the costume of funeral rite Investigating the birth and death years of the dead reveals that the excavated cos-tume was mostly used in the 16th and 17th centuries, . The study on the change of clothes in-cludes two aspects; one is manifestication of the structure of clothes and the other is elucidation of the constructure of clothes through examining constructure compo-nents and constructure compo-nents and construction method. This study investigates the costume of the midddle years of the Chosun dynasty in these aspects by examining the excavated Costume of 16th and 17th centries and Ryesu. This study also aims to assist to comprehend the constructure of costume by comparing actual excavated clothes with chronological standards through in-specting diverse clothes in a specified pe-riod. The construction of the clothes of the middle years of the Chosun dynasty is different depending on the purpose of theclothes and the principle of sewing is set up on the bases of mentality and body That is the Costume stands for the individual social and men-tal world of the people at that time since the external construction of the clothes represents their social rank and the inter-nal construction of sewing symbolizes their mentality. The characteristics features of the clothes of the middle years of the Chosun dy-nasty coexistence of diverse sorts and patterns indicates a change in clothes. This suggests that the clothes of a partic-ular class last and change in role corre-sponding to formation lasting and extinc-tion of the class. Thus diversityof the sort of general costume advancement of pattern and the change of clothes de-pending on the change of the class signify that the middle years of the Chosun- dy nasty is a period in which the general costume is actively developed and a turn-ing point for transforming the traditional clothes into new ones, . In other words the middle years of the Chosun dynasty is characterized as an era during which a castume native to Korea is formed with respect to the structure and constructure of clothes.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.37-47
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• 2013

Recently, lots of research results on program comparison have been reported since the code theft become frequent as the increase of code mobility. This paper proposes a plagiarism detection method using class structures. The proposed method constructs a graph representing the referential relationship between the member variables and the methods. This relationship is shown as a bipartite graph and the test for graph isomorphism is applied on the set of graphs to measure the similarity of the programs. In order to measure the effectiveness of this method, an experiment was conducted on the test set, the set of Java source codes submitted as solutions for the programming assignments in Object-Oriented Programming course of Pusan National University in 2012. In order to evaluate the accuracy of the proposed method, the F-measure is compared to those of JPlag and Stigmata. According to the experimental result, the F-measure of the proposed method is higher than those of JPlag and Stigmata by 0.17 and 0.34, respectively.

• Journal of the Korean Mathematical Society
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• v.46 no.2
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• pp.363-447
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• 2009

The author previously defined the spectral invariants, denoted by $\rho(H;\;a)$, of a Hamiltonian function H as the mini-max value of the action functional ${\cal{A}}_H$ over the Novikov Floer cycles in the Floer homology class dual to the quantum cohomology class a. The spectrality axiom of the invariant $\rho(H;\;a)$ states that the mini-max value is a critical value of the action functional ${\cal{A}}_H$. The main purpose of the present paper is to prove this axiom for nondegenerate Hamiltonian functions in irrational symplectic manifolds (M, $\omega$). We also prove that the spectral invariant function ${\rho}_a$ : $H\;{\mapsto}\;\rho(H;\;a)$ can be pushed down to a continuous function defined on the universal (${\acute{e}}tale$) covering space $\widetilde{HAM}$(M, $\omega$) of the group Ham((M, $\omega$) of Hamiltonian diffeomorphisms on general (M, $\omega$). For a certain generic homotopy, which we call a Cerf homotopy ${\cal{H}}\;=\;\{H^s\}_{0{\leq}s{\leq}1}$ of Hamiltonians, the function ${\rho}_a\;{\circ}\;{\cal{H}}$ : $s\;{\mapsto}\;{\rho}(H^s;\;a)$ is piecewise smooth away from a countable subset of [0, 1] for each non-zero quantum cohomology class a. The proof of this nondegenerate spectrality relies on several new ingredients in the chain level Floer theory, which have their own independent interest: a structure theorem on the Cerf bifurcation diagram of the critical values of the action functionals associated to a generic one-parameter family of Hamiltonian functions, a general structure theorem and the handle sliding lemma of Novikov Floer cycles over such a family and a family version of new transversality statements involving the Floer chain map, and many others. We call this chain level Floer theory as a whole the Floer mini-max theory.