• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.3
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• pp.224-235
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• 2014

Changes in the interactions among incident ocean water waves, coastal debris (marine debris), and the back vegetation zone line on a natural sandy beach on the island of Jinu-do in the Nakdong river estuary were investigated. The study involved a cross-sectional field survey of the beach, numerical modeling of incident ocean water waves, field observations of the distribution of coastal debris, and vegetation zone line tracking using GPS. The conclusions of this study can be summarized as follows: (1) The ground level of the swash zone (sandy beach) on Jinu-do is rising, and the vegetation zone line, which is the boundary of the coastal sand dunes, shows a tendency to move forward toward the open sea. The vegetation zone line is developing particularly strongly in the offshore direction in areas where the ground level is elevated by more than 1.5 m. (2) The spatial distributions of incident waves differed due to variations in the water depth at the front of the beach, and the wave run-up in the swash zone also displayed complex spatial variations. With a large wave run-up, coastal debris may reach the vegetation zone line, but if the run-up is smaller, coastal debris is more likely to deposit in the form of an independent island on the beach. The deposited coastal debris can then become a factor determining which vegetation zone line advances or retreats. Finally, based on the results of this investigation, a schematic concept of the mechanisms of interaction between the coastal debris and the coastal vegetation zone line due to wave action was derived.

• Journal of Navigation and Port Research
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• v.30 no.8 s.114
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• pp.649-655
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• 2006

Waves progressing into the coastal area can be amplified, swashed and overtopped by a wave overtopping control structure, and it converts the kinetic energy of the waves to the potential energy with a hydraulic head above the mean sea level by conserving the overflow in a reservoir. Then the potential energy in the form of hydraulic head can be converted to electric power utilizing extremely low-head hydraulic turbine. This study aims to find the most optimal shape of wave overtopping structure which maximizes overtopping volume rate of sea water. Laboratory experiments for the performance evaluation of wave overtopping control structures were carried out in three dimensional wave tank, and the three dimensional structure models with planar wave concentration shapes(B/b) were manufactured into five classes, which were optimized by cross sectional parameters of the structure, ie, length of ramp(l), gradient of inclined ramp($cot{\phi}$) and freeboard height of the wave overtopping structure($h_e$) proposed by Shin and Hong(2005). The wave overtopping discharges were investigated with 20 incident wave conditions and wave directions of $0^{\circ},\;15^{\circ},\;30^{\circ}$.

• Korean Journal of Community Nutrition
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• v.20 no.2
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• pp.129-140
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• 2015

Objectives: We examined the association between the adherence to dietary guidelines for breast cancer survivors and health-related quality of life in a cross-sectional study of Korean breast cancer survivors. Methods: A total of 157 women aged 21 to 79 years who had been diagnosed with stage I to III breast cancers according to the American Joint Committee on Cancer (AJCC) and had breast cancer surgery at least 6 months before the baseline were included. We used a Korean version of the Core 30 (C30) and Breast cancer 23 (BR23) module of the European Organization for Research and Treatment Cancer Quality of Life Questionnaire (EORTC-QLQ), both of which have been validated for Koreans. Participants were asked about their adherence to dietary guidelines for breast cancer survivors, suggested by the Korean breast cancer society, using a 5-point Likert scale. We summed dietary guideline adherence scores for each participant and calculated the least squares means of health-related quality of life according to dietary guideline adherence scores using the generalized linear model. Results: Breast cancer survivors who had higher adherence to dietary guidelines for breast cancer survivors had lower constipation scores than those with lower adherence (p for trend=0.01). When we stratified by the stage at diagnosis, this association was limited to those who had been diagnosed with stage II or III breast cancers. Also, sexual functioning scores increased significantly with increasing adherence scores of dietary guidelines among those with stage II or III breast cancers (p for trend < 0.001). However, among those who had been diagnosed with stage I, higher scores of dietary guidelines were associated with higher scores of pain (p for trend=0.03) and breast symptoms (p for trend=0.05). Conclusions: Our study suggested that the health-related quality of life levels of breast cancer survivors are associated with the adherence to dietary guidelines and may differ by the stage of the breast cancer.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.4
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• pp.277-285
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• 2019

This study was conducted to understand the growth characteristics of Picea jezoensis that was one of representative subalpine species in Korea, in the light of the effects of wind and micro-topography in its habitats on Mt. Deogyu, Korea. The prevailing wind directions were southwest and west at the study sites. We randomly selected P. jezoensis (height ≥ 1.5 m) on windward, intermediate, and leeward slopes and measured diameter at breast height (DBH), height, crown length by 8 directions in upper, middle and lower sectors of the crown. We examined the micro-topography of P. jezoensis stood on and classified it into 3 types: type 1 was mounded and fully exposed to surrounding environments without neighboring trees; type 2 was somewhat wind-protected by surrounding rocks, but no neighboring vegetation; type 3 was on gentle slope or flat where P. jezoensis grew with neighboring trees or shrubs. The ratios of height to DBH, and estimated crown growth to actual crown growth (hereafter crown growth ratio) were compared among the three types of micro-topography on windward, intermediate and leeward sites. The height growth per DBH and crown growth ratio in the upper and middle crowns were the smallest on the windward site, and the highest on the leeward site (p < 0.01). The crown growth ratio on type 1 on the windward site was only 46% of that on type 3 on the leeward site. Although on the same windward slope, trees on type 1 had more deformed crown shapes than that on Type 3, showing asymmetric crown cross-sectional areas. Wind and micro-topography played critical roles on the crown growth of P. jezoensis.

• Korean Journal of Clinical Laboratory Science
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• v.50 no.2
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• pp.155-163
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• 2018

Bilirubin has an anti-inflammatory effect as an endogenous antioxidant and has been reported to be inversely correlated with hypertension, diabetes, metabolic syndrome, and insulin resistance. On the other hand, there is a lack of research evaluating the association between bilirubin and metabolic syndrome compared to liver-specific indicators. This study examined the association between the total bilirubin and metabolic syndrome prevalence in Korean adults who underwent health screening compared to ALT and GGT. This cross sectional study included 22,568 adult males and females aged 20 years or older who underwent a health examination at the General Hospital of Gyeonggi Province from March 2015 to February 2018. Metabolic syndrome was diagnosed based on the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) guidelines. In both genders, the metabolic syndrome diagnosed group had higher liver enzymes, and the total bilirubin and direct bilirubin were lower than those without the metabolic syndrome risk factors. The serum total bilirubin showed a weak inverse correlation with abdominal obesity (r=-0.066 vs r=-0.055) and triglyceride (r=-0.127 vs r=-0.136) in both males and females, which is weaker than ALT and GGT The data were statistically significant. In addition, total bilirubin as well as ALT and GGT in both men and women were not predictors of the likelihood of developing metabolic syndrome.

• Journal of The Korean Association For Science Education
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• v.35 no.5
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• pp.919-929
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• 2015

This study aims to develop a modeling-based learning program about geologic structures and to reveal the relationship between the argumentation patterns and levels of students' mental models. Participants included 126 second grade high school students in four sessions of modeling-based learning regarding continental drift, oceanic ridges, transform faults, and characteristics of faults. A modeling-based learning program was implemented in two classes of the experimental group, and teacher-centered traditional classes were carried out for the other students in the comparison group. Science achievement scores and the distribution of students' mental models in experimental and comparison groups were quantitatively compared. The video-taped transcripts of five teams' argumentation were qualitatively analyzed based on the analytic framework developed in the study. The analytic framework for coding students' argumentation in the modeling-based learning was composed of five components of TAP and the corresponding components containing alternative concepts. The results suggest that the frequencies of causal two-dimensional model and cubic model were high in the experimental group, while the frequencies of simple two-dimensional model and simple cross sectional model were high in the comparison group. The higher the frequency of claims, an argumentation pattern was proven successful, and the level of mental model was higher. After the rebuttal was suggested, students observed the model again and claimed again according to new data. Therefore, the model could be confirmed as having a positive impact on students' argumentation process.

• The Journal of the Korean dental association
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• v.52 no.12
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• pp.744-752
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• 2014

There are many causes of oral mucosal diseases, so accordingly, there are various treatments available. The most commonly used agents include adrenocortical hormones, antifungals, antivirals, antibacterials, and immunosuppressants. However, it must also be noted that improving oral hygiene and nutrition, and reducing stress are effective in symptom relief. Furthermore, patients with existing diseases of the oral mucosa should avoid behavior that may cause an increase in pain. Unfortunately, many patients are unaware of the activities that may lead to increased pain and therefore do not avoid these activities. The aim of this study was to investigate and analyze the behavior of patients with oral mucosal disease with regard to activities that led to increase pain. This cross-sectional study was performed on a sample of patients with oral mucosal disease selected from the Oral Medicine Clinic of the Pusan National Hospital during March to August 2013. These patients were randomly selected. From a total of 479 patients, 116 patients with mucosal disease were selected and 73 fully completed questionnaires were included in the analysis. Data were collected by using self-completed questionnaires. The results were as follows: Mean score of Question 13 (Not smoking) is $2.47{\pm}1.11$. Mean score of Question 11 (Not drinking alcohol or not using mouthwash containing alcohol) is $2.22{\pm}1.15$. The other questions resulted in scores lower than 1.5. The answers to the questions were scored according to the following assigned numerical values: not keeping = score of 0; little keeping = score of 1; often keeping = score of 2; always keeping = score of 3. In conclusion, patients with oral mucosal diseases unknowingly engage in activities that result in an increase in pain. Therefore, they need to be educated about how to behave to protect oral mucosal lesion.

• The Journal of the Korean dental association
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• v.55 no.6
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• pp.413-422
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• 2017

Purpose: The aim of this study was to confirm the validity of the $Cariview^{TM}$, test in adults by assessing correlations between $Cariview^{TM}$, scores and caries experience using a quantitative light-induced fluorescence (QLF) technique. Methods: This retrospective cross-sectional study included 111 patients aged 19-64 years who visited a dental clinic in Seoul from 2015 to 2016, and underwent the $Cariview^{TM}$, test and had their teeth photographed with the Qraycam. Plaque was scraped with sterilized cotton swabs, and then placed in a culture medium and incubated at $37^{\circ}C$ for 48 h. Finally, the degree of color change was evaluated, and scored on a 0-100 point scale. Caries experience index included not only cavitated lesions but also early caries that were detected on white and fluorescence images. Participants were divided into low, moderate and high caries risk groups according to the $Cariview^{TM}$, score, and caries experience was compared between risk groups using ANCOVA. Spearman correlation coefficients were calculated to analyze the associations between $Cariview^{TM}$, scores and caries indices. Result: The mean age of the participants was 40 years, and the mean $Cariview^{TM}$, score was $53.6{\pm}20.7$. The WDMFT and the DMFT indices significantly increased with caries risk, and this increase was significantly different between the low- and high-risk groups. The $Cariview^{TM}$, test scores were significantly correlated with the WDMFT (r = 0.28, P = 0.003) and DMFT (r = 0.29, P = 0.002) indices. Conclusion: The $Cariview^{TM}$, test could be a clinically useful and simple method for assessing caries risk in adults.

• Korean Journal of Optics and Photonics
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• v.30 no.6
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• pp.243-248
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• 2019

The respiratory tract is an essential part of the respiratory system involved in the process of respiration. However, if stenosis occurs, it interferes with breathing and can even lead to death. Asthma is a typical example of a reversible cause of airway narrowing, and the number of patients suffering from acute exacerbation is steadily increasing. Therefore, it is important to detect airway narrowing early and prevent the patient's condition from worsening. Optical coherence tomography (OCT), which has high resolution, is suitable for observing the microstructure of tissues. In this study we developed an endoscopic OCT system. We combined a 1300-nm OCT system with a servo motor, which can rotate at a high speed. A catheter was pulled back using a linear stage while imaging with 360° rotation by the motor. The motor was selected considering various requirements, such as torque, rotational speed, and gear ratio of pulleys. An ex vivo rabbit tracheal model was used as a sample, and the sample and catheter were immobilized by acrylic structures. The OCT images provided information about the structures of the mucosa and submucosa. The difference between normal and stenosed parts in the trachea was confirmed by OCT. Furthermore, through a three-dimensional (3-D) reconstruction process, it was possible to identify and diagnose the stenosis in the 3-D image of the airway, as well as the cross-sectional image. This study would be useful not only for diagnosing airway stenosis, but also for realizing 3-D imaging.

• 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.