• The Journal of the Petrological Society of Korea
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• v.10 no.1
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• pp.1-12
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• 2001

A small of carbonate rocks and spatially-associated ultramafic rocks uniquely occur in the ulsan iron-serpentine mine of the sourtheastern Kyungsang basin. The study of field geology, core drilling data and stable isotope analysis suggest that the carbonate rocks are carbonatite formed from the melt reflecting intrusive natures. Based on this study, the geology of the Ulsan iron-serpentinite mining area consists of Cretaceous sedimentary, volcanic, granitic ultramafic and carbonate rocks in ascending order. The carbonate and ultramafic rocks show concentric and ellipsoidal shapes at the outcrop and a funnel shape in the cross sectional view. Carbon and oxygen stable isotope analysis show a bimodal pattern rather than a typical mantle pattern, which may indicate that the melt was a secondary melt generated within the crus not in the mantle directly. The uprising of ultramafic melts would have melted lime-contained rocks forming a secondary carbonate melt in the upper crus. Then, the intrusion of the ultramafic melts would have melted lime-contained rocks forming a secondary carbonate melt in the upper crust. Then, the intrusion of the ultramafic melt was followed by the intrusion of the carbonate melt along deep-seated fractures. Well-developed major fractures in this area, fluid inclusion characteristics of the carbonate rocks, the spatial relation between the ultramafic and carbonate rocks and stable isotope data support interpreting the Ulsan carbonate rocks as carbonatite.

• Corrosion Science and Technology
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• v.11 no.1
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• pp.1-8
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• 2012

The development of martensitic grades which can be processed in continuous galvanizing lines requires the reduction of the oxides formed on the steel during the hot dip process. This reduction mechanism was investigated in detail by means of High Resolution Transmission Electron Microscopy (HR-TEM) of cross-sectional samples. Annealing of a martensitic steel in a 10% $H_2+N_2$ atmosphere with the dew point of $-35^{\circ}C$ resulted in the formation of a thin $_{C-X}MnO.SiO_{2}$ (x>1) oxide film and amorphous $_{a-X}MnO.SiO_{2}$ oxide particles on the surface. During the hot dip galvanizing in Zn-0.13%Al, the thin $_{C-X}MnO.SiO_{2}$ (x>1) oxide film was reduced by the Al. The $_{a-X}MnO.SiO_{2}$ (x<0.9) and $a-SiO_{2}$ oxides however remained embedded in the Zn coating close to the steel/coating interface. No $Fe_{2}Al_{5-X}Zn_{X}$ inhibition layer formation was observed. During hot dip galvanizing in Zn-0.20%Al, the $_{C-X}MnO.SiO_{2}$ (x>1) oxide film was also reduced and the amorphous $_{a-X}MnO.SiO_{2}$ and $a-SiO_{2}$ particles were embedded in the $Fe_{2}Al_{5-X}Zn_{X}$ inhibition layer formed at the steel/coating interface during hot dipping. The results clearly show that Al in the liquid Zn bath can reduce the crystalline $_{C-X}MnO.SiO_{2}$ (x>1) oxides but not the amorphous $_{a-X}MnO.SiO_{2}$ (x<0.9) and $a-SiO_{2}$ oxides. These oxides remain embedded in the Zn layer or in the inhibition layer, making it possible to apply a Zn or Zn-alloy coating on martensitic steel by hot dipping. The hot dipping process was also found to deteriorate the mechanical properties, independently of the Zn bath composition.

• Journal of dental hygiene science
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• v.15 no.3
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• pp.340-347
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• 2015

The purpose of this study is to analyze the factors of oral function associated with number of present teeth (NT) in Korean elderly adults. The research was designed as cross-sectional study using the data of the 4th Korea National Health and Nutritional Examination Survey, and the samples were selected by stratified clusters sampling. The subjects aged 55 to 84 years were 4,780 that joined the oral examination survey and questionnaires. The respective variables reflecting socioeconomic status, subjective health status and oral function factor were analyzed and their distributional differences were confirmed by complex sampling logistic regression analysis. Multivariable liner regression models considering covariates were applied to explain the associations between the number of present teeth and other variables. Gender, educated level, illegal dental treatment, self-rated oral health and oral functional factors, including chewing behavior and speaking behavior, were associated with the number of present teeth (p<0.05). Subjects with better self-rated oral health had more NT than those with worse. Subjects with worse speaking behaviors had less NT than those with better. Interventions aiming to enhance oral health in elderly adults should consider socioeconomic, demographic, and oral functional factors.

• Korean Journal of Acupuncture
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• v.35 no.3
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• pp.130-138
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• 2018

Objectives : The purpose of this study is to explore patients' perceptions that deserve attention when designing core questions for a clinical practice guideline of Korean medicine(KM) for degenerative lumbar spinal stenosis (LSS). Methods : Patients who had been admitted to Pusan National Korean Medicine Hospital from November 1, 2015 to October 31, 2016 were invited to the survey. Patients were eligible if they were both clinically and radiologically confirmed as degenerative LSS. The structured questionnaire was distributed by mail and outpatient visits. Questions included types of experienced Korean/Western medical interventions for LSS, their perceived effectiveness on symptoms, the necessity for studies of KM for degenerative LSS, the types of KM interventions to be investigated and the types of outcome measures after treatments. Data were descriptively analysed. Results : Twenty of thirty-one invited participants responded to the questionnaire. Acupuncture and herbal medicine were the most frequently used KM interventions. Eighteen respondents reported that KM treatments were helpful for their improvement. Sixteen patients who mentioned that research on KM is needed chose acupuncture as the top priority(88%) among KM interventions. The most important outcomes in the view of nineteen respondents included functional recovery (68%) and pain relief (53%). Thirteen respondents (65%) replied that both short-term and long-term outcome were important for them. Conclusions : Our findings may have limited validity due to the small number of respondents and the potential selection and information bias. Further qualitative studies and large-scale surveys to comprehensively identify patients' views are warranted.

• Journal of Life Science
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• v.15 no.3 s.70
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• pp.352-358
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• 2005

The purpose of this study was to examine the effect of various exercise intensity on Resting Metabolic Rate (RMR), excess post exercise energy expenditure (EPEE), and thyroid hormonal changes in trained (TR) and untrained (UT) people. The subject of the present study were divided into two groups and four periods: trained (TR; n=6) and untrained (UT; n=6) group. And the periods were divided as follows; Resting (R), Maximal (M), High intensity (H), and Low intensity (L). The percent body fat and RMR of all subjects were measured at every periods. The RMR was measured early in the morning following a 12-hour fast using MMX3B gas analyzer and blood sample were collected from the anticubital vein to investigate thyroid hormonal (T3, T4, Free T3, Free T4, & TSH) changes. All the RMR values were expressed as absolute value/BSA $(kcal/d/m^2)$. And We also analyzed mean energy expenditure for 30 minutes during and after different intensity exercise. There was significant difference in RMR among different intensity of exercise. in TR (p < .05) not in the UT group. however, there was no significant different percent body fat in TR and in UT group. In the energy expenditure, there was significant different between TR and UT in HEE (high intensity exercise energy expenditure), LEE (low intensity exercise energy expenditure), HEEPE (high intensity exercise energy expenditure post exercise) & LEEPE (low intensity exercise expenditure post exercise). In the hormonal level, there was significant different in T4 level in the TR group at H period and in T4, Free T3, & Free T4 levels in TR group at L period, however there was no significant different in the UT group. The present cross-sectional study was design to investigate the relationship between exercise intensity and RMR. The focus of this investigation was to compare RMR in aerobically trained (TR) and untrained (VI). The relationship among RMR, exercise intensity and percent body fat would best be investigated using MMX3B and body composition analyzer. Each subject completed measurement of percent body fat, RMR, hormone in the period of maximal oxygen uptake exercise (M), high intensity exercise (H), and low intensity exercise (L). From the results, Low intensity of exercise (L), there was a trend for an increased RMR (kcal/day) in the TR not for the UT. This is best explained not by the reduced percent body fat but by the highly induced energy expenditure (during exercise and post exercise energy expenditure) and increased T4, Free T3, and Free T4 hormonal levels in the low intensity exercise for the TR group.

• Korean Journal of Human Ecology
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• v.5 no.2
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• pp.55-74
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• 2002

This study, observing each respectively packaged Kongdduk during 12-day storing period and comparing it with unpackaged Kongdduk, through a cross-sectional view of its fiber and temperament, through a sensory evaluation rheometer measurement of rheological change depending on storing period and packaging type and through the organic acid content, micro-organic change, and retrogressive process. The results are as follows: 1. Kongdduk made of bean oil shows better chewiness, cohesiveness, and moistness than Kongdduk made of bean flour while Kongdduk made of bean flour shows better rheological properties as to roasted nutty taste or roasted nutty order. 2. The test of the cutted loaves of Kongdduk shows that adding oil of proper proportion to the dough of steamed rice cake in accordance with the amount of rice flour has a good influence on rheological properties of softness. 3. Rice cakes were prepared by addition of yellow soybean flour or peanut flour and packaged with CMP or VP, and their physical characteristics were monitored by sensory evaluation and mechanical measurement while storing for 6 days. For VP samples, yellow soybean rice cake showed little changes in cohesiveness, moistness and chewiness for 6 days of storage, while pure rice cake and peanut rice cake showed an increase in strength and hardness from the 4th day of storage. In case of CMP, yellow soybean rice cake hardly showed a difference in cohesiveness, moistness and chewiness for 6 days, while pure rice cake and peanut rice cake showed a significant difference from the 4th day in sensory evaluation. 4. For rheometer measurement, yellow soybean rice cake with CMP or VP showed little changes in strength or hardness for 6 days, while peanut rice cake and pure rice cake showed a drastic decrease in cohesiveness, from the End day and adhesiveness from the 4th day of storage. As there was no remarkable difference or deterioration for 6 days of storage in yellow soybean rice cake between CMP and VP, the ingredients of rice cakeappeared to be more important than the type of packaging in terms of quality deterioration of rice cake. 5. As the storing period passed by, organic acid is detected less at CMP-packaged Knngdduk than at wrapped. and its increasing speed proves to be slower as well. 6. The one wrapped with plyethylene film began to get moldy from pure rice cake or Kongdduk (rice cake mixed with yellow soybean or peanut) after 6 days, and more and more modly after 9 daysor after 12 days, but the CMP-packaged ones didn't get modly until 12 days or more. 7. CMP-packaged Kongdduk showed higher enthalpy of retrogradation than PE-wrapped one. As storing Period Passed by, Kongdduk,s enthalpy grew high. That is to say, it shows that Kongdduk got retrograded.

• Fire Science and Engineering
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• v.33 no.4
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• pp.112-120
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• 2019

Benzene is a class 4 hazardous material according to the Act on the Safety Control of Hazardous Substances. This study qualitatively evaluated the damage size of a "toxic" accident and "pool fire" accidents based on benzene in a virtual scenario of a fire and leakage accident during unloading at a port facility. The KORA program was used as an evaluation method, which is supported as a universal program by the National Institute of Chemical Safety. The range of damage effects of a benzene-induced fire and leakage accident was predicted. In the case of toxic damage range, the accident's damage effect range for the "worst case scenario" was reduced by up to 5.11% with a decrease in the size of the leakage hole. In the case of the leakage time, the damage effect range increased to 145.12% with a 10 min leakage time compared to that of a 5 min leakage time and went up to 20 min (212.29%) with a 20 min leakage time. In the case of pool-fire-induced damage, the damage effect range by radiant heat in the "worst case scenario" was 228.8 m in radius from the center of the handling facility. In the "alternative scenario," the damage effect range by radiant heat was reduced by up to 8.26% compared to that in the "worst case scenario" since the size of the leakage hole was decreased by reducing the cross-sectional area of the pipe.

• Journal of Korea Water Resources Association
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• v.48 no.10
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• pp.807-816
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• 2015

In general, the water stage-discharge relationship curve is established based on the assumptions of linearity and homoscedasticity. However, the relationship between the water stage and discharge is affected from geomorphological factors, which violates the basic assumptions of the water stage-discharge relationship curve. In order to reduce the error due to the violations, the curve is divided into several sections based on the manager's judgement considering change of cross-sectional shape. In this research, the objective-splitting criteria of the curve is proposed based on the measured data without the subjective decision. First, it is assumed that the coefficient of variation follows the normal distribution. Then, if the newly calculated coefficient of variation is outside of the 95% confidential interval, the curve is divided. Namely, the groups is divided by the characteristics of the coefficient of variation and the reasonable criteria is provided for establishing a multi-segmented rating curve. To validate the proposed method, it was applied to the data generated by three artificial power functions. In addition, to confirm the applicability of the proposed method, it is applied to the water stage and discharge data of the Muju water stage gauging station and Sangegyo water stage gauging station. As a result, it is found that the automatically divided rating curve improves the accuracy and extrapolation accuracy of the rating curve. Finally, through the residual analysis using Shapiro-Wilk normality test, it is confirmed that the residual of water stage-discharge relationship curve tends to follow the normal distribution.

• Korean Journal of Materials Research
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• v.11 no.5
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• pp.405-412
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• 2001

Corrosion tests were carried out in $360^{\circ}C$ water and $360^{\circ}C$ 70ppm LiOH solution to investigate the corrosion behavior of new zirconium alloys (Zr-0.4Nb-0.8Sn-xFeCrMn, Zr-0.2Nb-1.1Sn-xFeCrMn, Zr-1.0Nb-xFeCu). Microstructures of tested alloys were analyzed by optical microscope and TEM. The cross-sectional surface and crystalline structure of the oxide layer were analyzed by SEM and XRD. From the results of corrosion test, all the alloys showed higher corrosion rates in $360^{\circ}C$ 70ppm LiOH aqueous solution thats in $360^{\circ}C$ water. Especially, high Nb-containing alloy exhibited the acceleration of corrosion rate in LiOH solution. The low Nb- and Sn-added alloys showed better corrosion resistance than the Sn- free high Nb alloy. from the effect of final annealing on the corrosion, it was observed that the partially recrystallized alloys showed better corrosion resistance than fully recrystallized alloys. This would be related to the size and distribution of the second phase particles.

• Journal of Korean Society for Geospatial Information Science
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• v.11 no.2 s.25
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• pp.17-28
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• 2003

Since 1970s, Seoul Metropolitan Area has been growing in physical and demographic aspect. A number of new urban fringes, New City, had been particularly developed from the early of 1990s. To examine the urban growth, the population density maps are generally used to the efficient urban management tool. The density maps from political boundaries, however, were traditionally used to estimate an urban concentration, there is problems to apply directly to urban management decision making due to (i) the abrupt changes between boundaries and (ii) the inclusion of green areas and forests in these areas. The mass-preserving interpolation method, the Pycnophylactic interpolation, could provide more realistic density maps. In addition, the classified urban areas from satellite images corresponding years would turn out to be more reliable results since populations were only applied to urbanized areas. Even though the Pyconophylactic method makes the density larger, it would be useful to produce a general urban growth trend at large scale. Consequently, four different density maps are compared and reviewed for this study, and the cross-sectional analysis provided to glimpse of population density around the city center.