• Restorative Dentistry and Endodontics
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• v.26 no.1
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• pp.86-94
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• 2001

기존의 광중합기는 높은 광강도를 제공함으로써 광중합 복합레진을 최대한 단축된 시간내의 중합을 목표로 하였다. 이러한 높은 광강도는 복합레진의 중합깊이, 중합률면에서는 우수하나 중합 반응속도가 빠름으로 인해 중합시 응력 발생이 높아진다는 일련의 보고가 있다. 최근에는 광중합 속도를 늦춤으로써 변연적합도 및 중합시 응력 발생을 낮추는 새로운 중합방법들이 제시되고 있다. 이에 본 실험에서는 광조사 강도의 변화가 광중합 복합레진의 중합반응 과정에 미치는 영향 및 중합된 복합레진의 중합률에 대한 영향을 분석하고자 하였다. 5개의 혼합형 광중합 복합레진 (Z-100, Spectrum, Z-250, Clearfil AP-X, P-60)을 사용하였으며 중합시 적용된 광조사 강도에 따라 6개의 실험군으로 정의하였다. 실험군과 이에 따른 광조사 방법은 다음과 같다. 1군은 110mW/$\textrm{cm}^2$로 40초 중합, 2군 210mW/$\textrm{cm}^2$로 40초 중합, 3군 410mW/$\textrm{cm}^2$로 40초 중합, 4군 620mW/$\textrm{cm}^2$로 40초 중합, 5군 110mW/$\textrm{cm}^2$로 10초 중합 후 1분 뒤 620mW/$\textrm{cm}^2$로 30초 중합, 6군 210mW/$\textrm{cm}^2$로 10초 중합 후 1분 뒤 410mW/$\textrm{cm}^2$로 30초 중합하였다. 광중합시 중합 반응 양상에 관한 분석은 시차주사 열계량기를 이용하여 37$^{\circ}C$ 항온상태에서 10분간의 열흐름곡선을 기록하였다. 기록된 열흐름곡선에서 중합 반응시 나타나는 중합열 및 최대 중합열에 이르는 시간을 기록하여 중합반응 속도를 측정하였다. 중합된 복합레진의 중합률은 Fourier Transform Infrared Spectrometer(FTIR)를 이용하였으며 2mm 두께의 복합레진 하방에서의 중합률을 측정하였다. 측정된 결과는 ANOVA 및 Student-Newman-Keuls 방법을 이용하여 유의성을 검증하였다. 실험결과 다음과 같은 결론을 얻었다. 1. 광중합 복합레진 중합시 광조사 강도가 증가할수록 중합열은 증가하였으나 통계적 유의성은 보이지 않았다 (p>0.05). 2. 최대 중합열에 이르는 시간은 광조사 강도가 증가할수록 단축되었다. 이단계 중합방법을 사용한 경우 중합반응 속도를 감소시킬 수 있음을 보였다. 3. 광조사 강도가 증가할수록 중합률은 증가하였다. 이단계 중합방법을 사용한 경우 연속적인 고광강도를 사용한 경우와 유사한 높은 중합률을 보였다. 4. 중합률면에서 광중합복합레진의 중합시 400mW/$\textrm{cm}^2$ 이상의 광강도가 필요한 것으로 나타났다.

• Journal of the Korean association of regional geographers
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• v.13 no.2
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• pp.220-233
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• 2007

In the context of region reconceptualized as a learning framework, using the Seoul region as an example, this paper focused on the debate and the condition of regional social studies curriculum in elementary schools, It means that regionalization of curriculum is the decentralization of power to develop and manage curriculum In that case, region is understood to he a resource used to connect the subject matter to children's experience, Furthermore, region is interpreted as Heimat, community and world around, Heimat is intended to be understood, loved and belonged to, Community is the resource for learning and the space of communication, participation and action, World around is the typical example to be searched, compared and explained by the concept and theory. On the base of the regionalization debate and the classification of learning a region, I analysed the local textbook, Social Studies Inquiry: Life in Seoul and suggested the framework of learning a region. In this paper, I tried to pick out the spatial demension of Seoul. It is classified into the space of experience, participation and inquiry, In conclusion, the region-specific materials and approach laying stress on the issue and topic in the geographical context of the region will determine that a proper regionalization occurs through not only methods hut also content.

• Journal of Conservation Science
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• v.28 no.4
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• pp.395-401
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• 2012

To investigate bioactive materials for development of natural conservative agent on organic cultural heritage, essential oil from Asarum sieboldii was screened for antifungal and insecticidal activity against 4 wood rotting fungi and adult of Lasioderma serricorne. Antifungal activity of essential oil was tested by using paper disc soaking method. Antifungal activity expressed as $IC_{50}$ value showed $1.50{\sim}2.84{\mu}l/disc$ range and the most significant antifungal activity was observed in Lentinus lepideus. The insecticidal activity of essential oil was examined by topical application method against L. serricorne adults. 50% and 100% of essential oil gave 98.3% and 100% mortality for 24 hours, respectively. The major components of the essential oil were methyl eugenol (56.32%), eucarvone (11.53%), safrole (5.79%), ${\delta}$-3-carene (2.09%), which were identified by gas chromatography-mass spectrometry. From these results, essential oil from A. sieboldii could be useful for conservation of organic cultural heritage against biological deterioration by insect and wood rotting fungi.

• The Journal of Engineering Geology
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• v.16 no.4 s.50
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• pp.337-349
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• 2006

Seven hundred and fifty one fractures of the rhyolitic tuffaceous rock masses were mapped using 6 scanlines placed on rock slope exposures that were within 8.02 km of Busan-Ulsan highway. These data were analyzed to find the number of fracture sets that exist in the rock slopes and the probability distributions of orientation, spacing, trace length and fracture size in 3-D for each of the fracture sets. All the fracture set orientation distributions exhibit high variability. The Fisher distributions were found to be unsuitable to represent the statistical distribution of orientation for most of the fracture sets. The probability distributions, gamma, exponential and lognormal were found to be highly suitable to represent the distribution of spacing and semi-trace length of fracture sets. In obtain-ing these distributions, corrections were applied for sampling biases associated with spacing and trace length. The generated fracture system in 3-D was used to make predictions of fracture traces for each fracture set on 2-D win-dows. Developed stochastic 3-D fracture network for the rock mass was validated by comparing statistical proper-ties of the observed fracture traces on scanlines with the predicted fracture traces on the scanlines. This exercise fumed out to be successful.

• Science of Emotion and Sensibility
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• v.15 no.1
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• pp.87-96
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• 2012

This paper proposes a Image retrieval system that searches the closest images to the user's emotional need and displays images with higher ratings of color harmony from Moon-Spencer's Color Harmony Theory first. Once an emotional adjective is placed, the system searches for images with colors that contain more elements derived from Aesthetic Measure results and displays in such order. In order to test reliability of the proposed emotion retrieval method based on Moon-Spencer's Color Harmony Theory, this study compared the order of Aesthetic Measure results with the user satisfaction ratings using 200 sample images. The analysis demonstrated that the participants' average satisfaction on 15 emotion adjectives selected for the study was 5.0 on a 7-point Likert scale. Correlation analyses were performed to test the consistency the orders between Aesthetic Measure values and user satisfaction ratings. Positive correlations above R=.5 were observed in all 14 emotion words except "Clear". These findings prove the potential of the proposed emotion retrieval system based on Moon-Spencer's Color Harmony Theory to effectively reflect user emotion in such visual stimulus search as image database.

• Korean Journal of Community Nutrition
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• v.19 no.5
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• pp.436-447
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• 2014

Objectives: The purpose of this study was to investigate the health food consumption patterns and their relationship to dietary behavior in middle-aged women (45-60 years). Methods: The exclusive face-to-face interviews by well-trained interviewers guaranteed a scientific data collection and the quality of survey data of 731 women. Subjects were divided into two groups according to the intake of the health foods, 'Intake' group (${\geq}3.2$, n = 488) and 'Non-intake' group (n = 243). Data were analyzed using the SPSS 20.0 program. Results: The average age of the subjects was 49.8 years and 66.8% of subjects were taking the health foods. Vitamins and minerals were consumed by the subjects. The major reason for intake of health foods was that they provide nutrient supplements may prevent diseases. More than 70% of the subjects reported checking nutrition information, ingredients, recommended daily intakes, instructions, when they bought the health foods. The average dietary life score of the intake group was significantly higher (p < 0.05) than that of the non-intake group. In analysis of exploratory factors of dietary life, the intake group showed significantly higher score (p < 0.001) in 'moderation of food intake' among the 4 exploratory factors. Conclusions: These results showed that women who took health foods had better dietary behavior than others suggesting a positive relation between the dietary behavior and the health food consumption. Therefore, we suggest that developing guidelines and then educating women about those guidelines could improve the ability of choosing health foods appropriately for their own benefit.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.1
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• pp.45-56
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• 2007

Direct estimation of the pollutant load(PL) should be carried out by the data filling in the missing intervals using an appropriate method because it is impossible in which the flow discharge(water quantity) or water quality(WQ) time-series data set have the missing intervals. In this study, the several methods estimating the water quality in the missing periods are suggested and the WQ and pollutants load change patterns are compared and evaluated based on the reproducible degree of the available data change patterns. The most appropriate method is finally suggested and the contribution factor deciding the influence degree and the PL characteristics of the river estuary is also suggested. Based on the PL estimation results using the several methods, the interpolation method considering the fluctuation of the available WQ data is shown to be most efficient. The PL patterns of the Han river estuary is classified as the discharge-dominated type. The data filling process is inevitable and the WQ estimation using the efficient and effective method should be carried out in order to estimate reasonable PL.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.6 s.165
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• pp.923-932
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• 2007

This research examines current viewpoints on modesty and immodesty in dress from a cross-cultural perspective. The purposes of this study was to explore the concept of modesty and to find out sub-variables of modesty, and the similarities and differences of modesty between two cultures. This qualitative interview study of 58 female college students in America and 36 in Korea examines attitudes about modesty. The data collection was performed in America and Korea simultaneously in Feb. 2004. According to the results of this study, the concept of modesty had 4 sub-variables such as covering up, appropriateness, drawing attention from others, and conservativeness. Both American and Korean students mentioned that time and place are closely related with modesty and that modesty was related with gender. Also cultural differences were existed.

• The Journal of the Korea Contents Association
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• v.17 no.9
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• pp.203-211
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• 2017

The purpose of this study was to determine the association of some adult dental fear and depression, and stress. Among the patients who came to the dental clinic for periodontal treatment, 68 patients who agreed to participate in the study and who met the selection criteria were included. Dental fear, depression symptom questionnaire, salivary cortisol, which can objectively evaluate blood pressure, pulse, and stress. The results of the analysis showed that depressive symptom was related to 'delayed treatment promise', 'cancellation of treatment appointment', 'increased muscle tension', 'rapid breathing when entering dentistry', 'fear when waiting in the waiting room', 'fear when you smell the hospital', 'fear when looking at the dental clinic', 'fear when seeing the anesthetic needle', 'fear when tooth whistle was heard', 'fear when teeth were removed', and 'total fear of dentistry'(p<0.05). Stress symptoms were higher in 'having sweated in the dentist', 'faster pulse', 'fear of entering the dentist' and 'total fear of the dentist'(p<0.05). Based on these results, it is necessary to study the effective methods to control the depressive symptoms and stress of patients who visit dental clinics, and it seems that continuous management is needed to prepare methods such as relaxation therapy for dental fear patients.

• Economic and Environmental Geology
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• v.29 no.6
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• pp.699-712
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• 1996

Field scale experiments using an automated 144-channel TDR system were conducted which monitored the movement of solute through unsaturated loamy soils. The experiments were carried out on two different field plots of 0.54 ha to study the vertical movement of solute plume created by applying a square pulse of $CaCl_2$ as a tracer. The residence concentration was monitored at 24 locations on a transect and 5 depths per location by horizontally-positioning 50 cm long triple wire TDR probes to study the heterogeneity of solute travel times and the governing transport concept at field scale. This paper describes details of experimental methodology and calibration aspects of the TDR system. Three different calibration methods for estimation of solute concentration from TDR-measured bulk soil electrical conductivity were used for each field site. Data analysis of mean breakthrough curves (BTCs) and parameters estimated using the convection-dispersion model (CDE) and the convective-lognormal transfer function model (CLT) reveals that the automated TDR system is a viable technique to study the field scale solute transport providing a normal distribution of resident concentration in a high resolution of time series, and that calibration method does not significantly affect both the shape of BTC and the parameters related to the peak travel time. Among the calibration methods, the simple linear model (SLM), a modified version of Rhoades' model, appears to be promising in the calibration of horizontally-positioned TDR probes at field condition.