• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.1
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• pp.43-52
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• 2006

Topical fluoride application for children is a widely peformed procedure in the field of pediatric dentistry to prevent dental caries. However, it is recently recognized as having some unwanted effects on several esthetic restorative materials as it roughens the surface of the restorative materials. The aim of this study was to evaluate the surface changes in composite resins to topical fluoride. Composite resins(Z $250^{(R)}$, Ultraseal $XT^{(R)}$ Filtek $flow^{(R)}$ $Revolution^{(R)}$, $Denfil^{(R)}$) in topical fluoride agents were immersed and their surface roughness, weight loss and SEM were evaluated. The results were as follows : 1. The 4 minutes-immersion groups showed more roughened surface than 1 minute-immersion groups and the control groups showed the smoothest surface among all the materials, and there was statistically significant difference except the revolution between the groups. 2. There was no significant difference between the 1 minute-immersion groups and 4 minutes-immersion groups in weight loss. 3. The experimental group treated with topical fluoride gel showed the generally mere roughened surface than control group in the SEM findings.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.2
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• pp.219-227
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• 2001

Little is known about processing mechanism of pain sensation of the oral cavity at the 1st synapse of trigeminal sensory nuclei. Serial ultrathin sections of tooth pulp afferent terminals, identified by the transganglionic transport of 1% wheatgerm agglutinin conjugated horseradish peroxidase, were investigated with electron microscope. Quantitative ultrastructural analysis was performed on digitizing tablet connected to Macintoshi personal computer (software; NIH Image 1.60, NIH, Bethesda, MD). Labeled boutons could be classified into two types by the shapes of containing vesicles : S bouton, which contained mainly spherical vesicles (Dia. 45-55 nm) and few large dense cored vesicles (Dia, 80-120nm), and LDCV bouton, which contained spherical vesicles as well as large number of large dense cored vesicles. Most of the parameters on the ultrastructural characteristic and synaptic organization of labeled boutons were similar between S and LDCV boutons, except shapes of containing vesicles. Majority of the labeled boutons showed simple synaptic arrangement. The labeled boutons were frequency presynaptic to dendritic spine, and to a lesser extent, dendritic shaft. They rarely synapsed with soma and adjacent proximal dendrite. A small proportion of labeled boutons made synaptic contacts with presynaptic, pleomorphic vesicles containing endings and synaptic triad. Morphometric parameters of labeled boutons including volume and surface area, total apposed area, mitochondrial volume, active zone area, vesicle number and density showed wide variation and these were not significantly different between S and LDCV boutons. The present study revealed characteristic features on ultrastructure and synaptic connection of pulpal afferents which may involved in transmission of oral pain sensation.

• Journal of The Korean Association For Science Education
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• v.23 no.5
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• pp.544-560
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• 2003

The purposes of this study were (1) to investigate the characteristics of the exhibits at three representative science centers or museums in Seoul, and (2) to analyse students' perceptions about the most and the least favorite exhibits selected by students as visitors. Three science centers investigated were Seoul National Science Museum, Seoul Education & Science Research Institute, LG Science Hall. The subjects for students' perception survey were 290 middle school students who visited the three science centers. The investigation of the exhibits showed that the goals, the contents, the visitors' viewing and manipulating activity types, and the explanation types of the exhibits depended on the purposes and the target visitors of each science center. Students' responses indicated that they most favored hands-on exhibit. And students preferred the exhibits that had new and comprehensible contents and the were related to what they had learned in school. Students said that they felt that science was exciting and that they came to experience what they did not do in school. Students said that reading or hearing given explanations was helpful to understand the exhibits, but about 20% of the students responded that they did not read explanation on panels at all. Students also said that guide's oral explanations were more understandable than written explanations on panels. Some of the students commented that having to wait for access because of crowds or because of the resetting time required for hands-on activities was inconvenience.

• The Korean Journal of Air & Space Law and Policy
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• v.25 no.1
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• pp.159-203
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• 2010

Together with the development of space science outer space law has become one of the most rapidly developing branches of international law. This reflects a general realization that these new activities must be subject to reasonable legal regulation if they are to serve the peaceful purposes of mankind without undue confusion and disorder. The exploration and use of outer space introduces many novel opportunities and dilemmas, and inspired insights are needed in the development of this new resource. In particular, the settlement of space law disputes is a relatively new discussion in international law. However, the significance of the settlement of space law disputes was acknowledged in various colloquia organized by legal academicians and practitioners around the world. Analysis of the dispute settlement provisions in space agreements plainly reveals the degree to which States persist to be mistrustful of any impingement to their sovereignty. They are reluctant to submit disputes to adjudication and binding arbitration, particularly when these provisions are negotiated between States which have dissimilar political, economic and social interests and demography. However, there is a slow but clear shift in this attitude as States realize the contemporary political, economic and technical pressures necessitating the lifting of the veil of State sovereignty. The development of an effective mechanism for the settlement of disputes arising in relation to the development of the exploration and exploitation of outer space has been the subject of global study by highly qualified publicists and international institutions. The 1972 Liability Convention is the space treaty with the most elaborate provisions for dispute settlement. However, it fails to ensure binding decisions. In this point, the 1998 Taipei Final Draft Convention may be a useful instrument for further consideration on whether an independent sectorialized dispute settlement mechanism should be established. Considering these circumstances it seemed essential to take legislative action to implement a system as comprehensive as the relevant legal framework are in the Law of the Sea and International Criminal Law mechanisms for dispute settlement and conflict avoidance from outer space activities.

• Journal of Digital Contents Society
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• v.13 no.2
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• pp.225-233
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• 2012

The 3D stereoscopic image contents have been emerging as the blue chip of the contents market of the next generation since the . However, all the 3D contents created commercially in the country have failed to enter box office. It is because the quality of Korean 3D contents is much lower than that of overseas contents and also current 3D post production process is based on 2D. Considering all these facts, the 3D editing process has connection with the quality of contents. The current 3D editing processes of the production case of are using the way that edits with the system on basis of 2D, followed by checking with 3D display system and modifying, if there are any problems. In order to improve those conditions, I suggest that the 3D editing process contain more objectivity by visualizing the depth data applied in some composition work such as Disparity map, Depth map, and the current 3D editing process. The proposed process has been used in the music drama , comparing with those of the film . The 3D values could be checked among cuts which have been changed a lot since those of , while the 3D value of drew an equal result in general. Since the current process is based on an artist's subjective sense of 3D, it could be changed according to the condition and state of the artist. Furthermore, it is impossible for us to predict the positive range, so it is apprehended that the cubic effect of space might be perverted by showing each different 3D value according to cuts in the same space or a limited space. On the other hand, the objective 3D editing by applying the visualization of depth data can adjust itself to the cubic effect of the same space and the whole content equally, which will enrich the 3D contents. It will even be able to solve some problems such as distortion of cubic effect and visual fatigue, etc.

• Fashion & Textile Research Journal
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• v.1 no.3
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• pp.252-258
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• 1999

The aims of this study is to classify the lower somatotype of adult women and appearance analysis on the shape of flare skirts by using the image processing. Also We have made skirts in order to analyze the various types of appearance of flare skirts by using the image processing. The subjects for our wear test lower somatotype, who were controlled in their waist, abdomen and hip shapes. The flare skirts used for wear test were 112 types(combinated 14 fabric type and 8 lower somatotype). The effect of lower somatotype on the shape of flare skirts was determined by the horizontally hem line section shape and the silhouette of flare skirts with image processing. The data were analyzed by using analysis of variance and Turkey, Duncan multiple range test. The results obtained are summarized as follows: It is shown that the fabric weight elongation differs in fabrics properties, in direction of textures. The shape horizontal section of flare skirt hem line has differed with the number of nodes, wave-height of nodes and breadth of silhouette by fabrics properties and lower somatotype. It is noticed that the breadth of flare skirts by the silhouette has high correlation with the drape ability of fabrics and lower somatotype. Results for our flare skirts show changes in amplitude and mean with fabrics, somatotype. Therefore we can say that gray-level histograms are correlated with changes in appearance, differences in drape spacing and related fabric properties and their somatotype.

• Journal of Oral Medicine and Pain
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• v.30 no.1
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• pp.87-106
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• 2005

In order to evaluate the mechanism of transmission as well as processing of sensory information originating from low-threshold mechanoreceptor in oral and maxillofacial region at primary synaptic region of trigeminal nervous system, vibrissa afferent fibers of adult cat were labeled with intra-axonal HRP injection. Serial sections containing labeled boutons were obtained from the piece of trigeminal interpolar nucleus. Under electron microscope, total 30 labeled boutons were observed, and ultrastructural characteristics, frequency of occurence, synaptic organizations of vibrissa afferent terminals were analysed. The results were as follows: 1. Labeled boutons contained clear, spherical synaptic vesicles with diameter of 45$\sim$55nm. They formed asymmetrical synapse with dendrites showing definite postsynaptic density, larger synaptic cleft, multiple synaptic structures at various regions. With unlabeled axon terminals(p-ending) containing polymorphic synaptic vesicles, they formed symmetrical synapse showing indefinite postsynaptic density and narrower synaptic area. 2. Each labeled bouton formed 1 to 15 synapses, the average of 4.77$\pm$3.37 contacts per labeled bouton, with adjacent neuronal profiles. Relatively complex synaptic organization, which formed synapses with more than 5 neuronal profiles, was observed in a large number(46.7%, n=14) of labeled boutons. 3. Axo-somatic synapse was not observed. The number of axo-dendritic synapse was 1.83$\pm$1.37 per labeled bouton. Majority(85.0%) of axo-dendritic synapses were formed with dendritic shafts, nonprimary dendrites(n=47, 1.57$\pm$1.38/1 bouton), however, synapses formed with primary dendrites(n=6, 0.20$\pm$0.41/1 bouton) or dendritic spines(n=2, 0.07$\pm$0.25/1 bouton) were rare. 4. 76.7%(n=23) of labeled boutons formed axo-axonic synapse (2.93$\pm$2.36/1 bouton) with p-endings containing pleomorphic vesicles. Synaptic triad, in which p-endings formed synapses with labeled boutons and dendrites adjacent to the labeled boutons simultaneoulsy, were also observed in 60.0%(n=18) of labeled boutons. From the above results, vibrissa afferent terminals of adult cat showed distinctive synaptic organization in the trigeminal interpolar nucleus, thus, suggests their correlation with the function of the trigeminal interpolaris nucleus, which participates in processing of complex sensory information such as two-point discrimination and motivational-affective action. Further studies on physiologic functions such as quantitative analysis on ultrastructures of afferent terminals and nerve transmitters participating in presynaptic inhibition are required.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.3 no.1
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• pp.26-45
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• 1992

This study presents the behavioral and cognitive changes by administration of methylphenidate(MPH) and imipramine(IMI) for the treatment of attention-deficit hyperactivity disorder(ADHD) in $5_{1/2}{\sim}12$ years old children referred to child psychiatric clinics. Behavioral changes are assessed with parent's and teacher's ratings. Drug effects on attention. short-term memory, and impulsivity are evaluated with psychological tests in laboratory. The changes were assessed twice in a 8-week periods. The data were analyzed seperately for 15 subjects each drug using repeated measured analysis of variance(ANOVA). The findings indicates that behavioral and cognitive impairments are improved by both drugs, but impulsivity is not. And MPH is superior to IMI on the improvement of attentional problem ; especially the findings indicates important differences between simple task and complex. perceptual-search task. These data confirm the effectiveness of MPH for treatment of ADHD, also raise questions regarding assessment method of attention and impulsivity as fell as importance of impulsivity in ADHD.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.14 no.1
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• pp.12-25
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• 2003

Objectives：As increasing number of new antidepressants have been being introduced in clinical practice, pharmacological understanding has been broadened. These changes mandate new information and theories to be incorporated into the treatment process of children with depressive disorders. In light of newly coming knowledge, this review intended to recapitulate the characteristics of new antidepressants and to consider the pivotal issues to develope guidelines for the treatment of depression in childhood and adolescence. Methods：Searching the Pub-Med online database for the articles with the key words of 'new', 'antidepressants' and 'children' ninety-seven headings of review articles were obtained. The author selected the articles of pertinent subjects in terms of either treatment guideline or psychopharmacology of new antidepressants. When required, articles about the clinical effectiveness of individual antidepressants were separatedly searched. In addition, the safety information of new antidepressants was acquired by browsing the official sites of the United States Food and Drugs Administration and Department of Health and Human Services. Results：1) For the clinical course, treatment phase, and treatment outcome, the reviews or treatment guidelines adopted the information from adult treatment guidelines. 2) Systematic and critical reviews unambiguously concluded that selective serotonin reuptake inhibitors(SSRIs) excelled tricyclic antidepressants( TCAs) for both efficacy and side effect profiles, and were recommend for the first-line choice for the treatment of children with depressive disorders. 3) New antidepressants generally lacked treatment experiences and randomized controlled clinical trials. 4) SSRIs and other new antidepressants, when used together, might result in pharmacokinetic and/or pharmacodynamic drug-to-drug interaction. 5) The difference of the clinical effectiveness of antidepressants between children and adults should be addressed from developmental aspects, which required further evidence. Conclusion：Treatment guidelines for the pharmacological treatment of childhood and adolescence depression could be constructed on the basis of clinical trial findings and practical experiences. Treatment guidelines are to best serve as the frame of reference for a clinician to make reasonable decisions for a particular therapeutic situation. In order to fulfill this role, guidelines should be updated as soon as new research data become available.

• Journal of the Korean Magnetics Society
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• v.15 no.6
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• pp.315-319
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• 2005

To obtain low switching field ($H_{SW}$) we introduced amorphous ferromagnetic $Co_{70.5}Fe_{4,5}Si_{15}B_{10}$ single and synthetic antiferromagnet (SAF) free layers in magnetic tunnel junctions (MTJs). The switching characteristics for MTJs with structures $Si/SiO_2/Ta$ 45/Ru 9.5/IrMn 10/CoFe 7/AlOx/CoFeSiB 7 or CoFeSiB (t)/Ru 1.0/CoFeSiB (7-t)/Ru 60 (in nm) were investigated and compared to MTJs with $Co_{75}Fe_{25}$ and $Ni_{80}Fe_{20}$ free layers. CoFeSiB showed a lower saturation magnetization of $560 emu/cm^3$ and a higher anisotropy constant of $2800\;erg/cm^3$ than CoFe and NiFe, respectively. An exchange coupling energy ($J_{ex}$) of $-0.003erg/cm^2$ was observed by inserting a 1.0 nm Ru layer in between CoFeSiB layers. In the CoFeSiB single and SAF free layer MTJs, it was frond that the size dependence of the $H_{SW}$ originated from the lower $J_{ex}$ experimentally and by micromagnetic simulation based on the Landau-Lisfschitz-Gilbert equation. The CoFeSiB SAF structures showed lower $H_{SW}$ than that of NiFe, CoFe and CoFeSiB single structures. The CoFeSiB SAF structures were proved to be beneficial far the switching characteristics such as reducing the coercivity and increasing the sensitivity in micrometer to submicrometer-sized elements.