• The korean journal of orthodontics
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• v.27 no.2
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• pp.197-208
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• 1997

Class III malocclusion patients can be approached with many different types of treatment methods, and thus, each patient's problems must be accurately evaluated to allow selection of the best possible treatment method. Cephalometric analysis is an essential part of diagnosis and treatment planning of orthodontic patients, and it would certainly be helpful if reliable cephalometric guidelines could be set. The author divided 482 Class III malocclusion patients(253 males and 229 females) into fourgroups according to different types of treatment methods they have received to correct imbalance between upper and lower jaws: 1) orthopedic appliance (face mask & RPE), 2) camouflage treatment with fixed appliance, 3) surgical-orthodontic treatment, 4) cross-bite correction with removable plates/ functional appliance. Cephalometric values at the time of first clinical examination were compare among the four groups. Cephalometric analysis indicates the following results: 1)the amounts of antero-posterior and vertical skeletal discrepancies and dental compensation were greatest in surgery group 2) SNB, Wits, distance from Nasion Perpendicular Plane to point a facial angle, facial convexity, and APDI were greater in orthopedic appliance group than fixed appliance(camouflage) group, but there was no statistical difference 3) removable plates/ functional appliance group showed least amounts of skeletal discrepancies and dental compensation with statistical significance.

• Journal of the Korean Applied Science and Technology
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• v.32 no.2
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• pp.215-225
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• 2015

Recently, the importance of energy saving and alternative energy is significantly increasing due to energy depletion and the phase change material (PCM) research for saving energy is also actively investigating. In this research, the membrane emulsification using SPG membrane was used to make various microencapsulated phase change material (MPCM) particles which were comprised of $Rubitherms^{(R)}$ (RT-21 and RT-24) core and silica coating. We investigated the pressure of the dispersion phase, the concentration of surfactant, and the ratio of $Rubitherm^{(R)}$ and silica to prepare various MPCM particles. The DSC and TGA were used to examine the heat stability and latent heat properties. Also, PSA, SEM, and optical microscopy were used to confirm the size of $Rubitherm^{(R)}$ particles and the thickness of silica shell. The average of particle size was $7-8{\mu}m$. And, FT-IR was also used to enforce the qualitative analysis. Finally, the MPCM particles obtained from membrane emulsification showed monodispersed size distribution and the heat stability and latent heat were kept up to 80% compared to pure $Rubitherm^{(R)}$. So, it can be effectively used for wallpaper, buildings and interior products for energy saving as PCMs.

• Journal of Life Science
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• v.30 no.1
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• pp.88-95
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• 2020

Using a random arbitrarily primed polymerase chain reaction, messenger RNA expression levels were assessed after exposure to 10% (v/v) toluene for 8 hr in solvent-tolerant Pseudomonas sp. BCNU 106. Among the 100 up-expressed products, 50 complementary DNA fragments were confirmed to express repeatedly; these were cloned and then sequenced. Blast analysis revealed that toluene stimulated an adaptive increase in the gene expression level in association with transcriptions such as LysR family of transcriptional regulators and RNA polymerase factor sigma-32. The expression of catalase and Mn2+/Fe2+ transporter genes functionally associated with inorganic ion transport and metabolism increased, and the increased expression of type IV pilus assembly PilZ and multi-sensor signal transduction histidine kinase genes, functionally categorized into signal transduction and mechanisms, was also demonstrated under toluene stress. The gene expression level of beta-hexosaminidase in association with carbohydrate transport and metabolism increased, and those of DNA polymerase III subunit epsilon, DNA-3-methyladenine glycosylase II, DEAD/DEAH box helicase domain-containing protein, and ABC transporter also increased after exposure to toluene in DNA replication, recombination, and repair, and even in defense mechanism. In particular, the RNAs corresponding to the ABC transporter, Mn2+/Fe2+ transporter, and the β-hexosaminidase gene were confirmed to be markedly induced in the presence of 10% toluene. Thus, defense mechanism, cellular ion homeostasis, and biofilm formation were shown as essential for toluene tolerance in Pseudomonas sp. BCNU 106.

• Journal of the Korea Institute of Building Construction
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• v.17 no.2
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• pp.157-166
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• 2017

In general, carbonation and chlorine ions are the most harmful causes of deterioration of concrete structures. Recently, a method has been developed to control the corrosion of rebar in concrete containing chloride by impregnating a Surface coating material with a inhibitor. In this study, accelerated carbonation and differential thermogravimetric analysis (TG-DTA) and CASS tests were carried out to evaluate the characteristics of Surface coatings containing Organic Corrosion inhibitors which are excellent in corrosion inhibition and fix degradation causes $CO_2$ and $Cl^-$. As a result of the experiment, TG-DTA analysis and accelerated carbonation showed that $CO_2$ was directly reacted with amine derivative in concrete by the incorporation of Organic Corrosion inhibitor. In other words, $CO_2$ was immobilized and carbonation inhibition effect was confirmed. In addition, in the CASS test, the specimen coated with the Surface coating material containing the Organic Corrosion inhibitor with $Cl^-$ fixing property showed no corrosion until the 28th day and had excellent performance in preventing corrosion of a rebar by the chloride ion.

• Journal of the Korean Geographical Society
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• v.43 no.6
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• pp.791-807
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• 2008

The purpose of this study is to analyze landform characteristics and geomorphic processes in Dokdo seamount. For geomorphic analysis, bathymetry data were collected by multi-beam echosounder and the seismic survey was also conducted. Through the detailed analysis of depth, slope, aspect and erosional landform, Dokdo Seamount is characterized by a flat or gently sloping top of $2^{\circ}$ or less and seamount slope with $14{\sim}40^{\circ}$ gradient. There are protrusion of landform around the Dokdo on top of the Dokdo seamount. It is inferred that the features are formed by collapsed debris deposits or remained bedrocks by differential erosion in the past. The massmovement topography including slump and slide is shown on seamount slope with $14{\sim}40^{\circ}$ gradient. In addition, gullies with various length are developed on the Dokdo seamount slope. Slope erosional processes occur more actively along the submarine gullies on the Dokdo seamount. It is inferred that the massmovement processes on the slope of Dokdo seamount are related to earthquake activities and evolution of submarine volcano. Consequently, slope of the Dokdo seamount has retreated by erosional processes of mass-movement and submarine gullies.

• Korean Journal of Social Welfare
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• v.64 no.2
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• pp.273-298
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• 2012

This study is targeted to understand the giving of time and money among citizens in Seoul. It explores predictors of different combinations of giving behaviors: only volunteering, only donating, doing both, and neither. In exploring predictors, it also considers the effects of intensity in giving with differential measurement of general participation and regular participation. For the analysis, this study utilizes Seoul Welfare Panel Survey Data in 2008 and 2010 and employes a multi-nominal logistic regression model with selection of citizens' demographic factors, pro-social attitude factors, and psycho-social factors on these four type of giving behaviors. The findings show that previous giving experiences(+) and religious activities(+) have statistically significant effects on both selective and combined giving behavior. Gender(woman), income(+), education(+) have statistically significant effects on giving behaviors(only donating and doing both) related with donation. In the case of employment state, unemployment is significantly related to volunteering while employment is significantly related to donating. Finally, happiness(+) has significantly positive effect on intensive giving such as regular giving rather than general giving. This analysis has made a start in a new area of inquiry attempting to explain different giving behaviors with broadening and promoting understanding on giving behaviors. Moreover, it raises several implications for future research and strategic practice for resource mobilization of NPOs.

• The Journal of Engineering Geology
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• v.24 no.3
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• pp.373-381
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• 2014

It is difficult to predict the magnitude of a rockfall with respect to the shape, volume, and weight of the rock mass, as a rockfall exhibits erratic behavior that depends on the slope geometry, such as the height and dip of the slope. In this study, a field survey was conducted on the slopes of Ulleung-Do, South Korea, where rockfalls frequently occur along coastal roads, to classify the mode of rockfalls and estimate their magnitude. This study also analyzed the effects of rockfall behavior on roads by applying a simulation technique. Agglomerate and trachytic rocks distributed across the study area produce rockfalls in a differential weathering rockfall mode and a toppling rockfall mode. In terms of rockfall weight, trachytic rockfalls were 2-3 times heavier than agglomerate rockfalls. An analysis of rockfall behavior from the simulation indicates that the impact energy on the road exceeded the absorbing energy of a standard rockfall protection fence; however, the rockfall was secured when a ring-net was applied.

• Applied Chemistry for Engineering
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• v.26 no.5
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• pp.538-542
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• 2015

In this work, effects of the blend composition composed of 0, 10, 20, 30 and 40 wt% of nylon 6 to epoxy (diglycidylether of bisphenol-A, DGEBA) resin were investigated in terms of cure kinetics and thermal stability by differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA). As the content of the nylon 6 increased, the maximum exothermic temperature ($T_{max}$) and the value of cure activation energy ($E_a$) decreased. The maximum exothermic temperature of the blending samples decreased with increasing in nylon 6 content, resulting in the decrease in curing activation energy of them due to the rapid curing reaction with epoxy resin in this system. From TGA analysis results of the DGEBA/nylon 6, the thermal stability based on the thermal stability index ($A^*{\cdot}K^*$) and integral procedure decomposition temperature (IPDT) increased with increase in the nylon 6 content. This was because of the combination of DGEBA and nylon 6 having good heat resistance, resulting in improving thermal stability of the DGEBA/nylon 6.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.20 no.1
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• pp.24-28
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• 2020

Type III Glycogen storage disease (Type III GSD, OMIM#232400) is a genetic metabolic disorder in which undigested glycogen accumulates in the organs due to lack of glycogen debranching enzyme caused by AGL mutation. The clinical symptoms of type III GSD include hepatomegaly, delayed growth, hypoglycemia and muscle weakness. These clinical symptoms are similar to those of other types of GSD, making it difficult to distinguish clinically. The authors report a case of type III GSD diagnosed by gene panel sequencing. A 11-month old male patient was presented with hepatomegaly. In liver biopsy, glycogen was accumulated in hepatocytes, suggesting GSDs. For differential diagnosis of types of GSD, gene panel sequencing for GSDs was performed. As a result, two novel pathogenic compound heterozygous variants: c.311_312del (p.His104Argfs*15) and c.3314+1G>A in AGL were detected and the patient was diagnosed as type III GSD. After diagnosis, he started dietary treatment with cornstarch, and has been free from complications. After two years, two same variants were also identified in the chorionic villous sampling of the pregnant mother, and the fetus was diagnosed as type III GSD. Gene panel sequencing is useful for diagnosis of disease which is indistinguishable by clinically and has high genetic heterogeneity, such as GSD. After diagnosis, familial genetic analysis can provide adequate genetic counseling and rapid diagnosis.

• Communications of Mathematical Education
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• v.29 no.3
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• pp.423-439
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• 2015

This study examines the relationship between prior learning experience, the high school records, mathematics grade in the KSAT(Korean Scholastic Aptitude Test) and mathematics achievement, GPA(grade point average) of college freshmen. It analyses how much mathematics capacities in the time of high school affect mathematics achievement of college freshmen. This study surveyed 193 freshmen, attending in a college of science and engineering, taking the 'basic differential and integral calculus' lecture, which was opened for the first semester of 2014 in the A university. The data processing was fulfilled by means of technical statistics, correlation analysis, difference test, ANOVA, ex post facto test, and regression analysis. The outcomes of this survey are followings: Firstly, over 90 percent of college freshmen underwent prior learning of mathematics when they attended high school. Secondly, their perception of effectiveness for prior learning is founded to be meaningfully lower than their perception of its needfulness. Thirdly, while there is higher positive correlation between mathematics achievement and GPA in the college, there is little correlation between high school records and GPA in the college. Also, there is little correlation between mathematics grade in the KSAT and mathematics achievement in the college. Fourthly, the accomplishments in the high school(The high school records, mathematics grade in the KSAT) and the efforts, satisfaction, necessity, etc. for prior learning had little effect on academic achievement in college mathematics. Based on these results, this study makes some suggestions for developing academical achievement in college mathematics.