• Restorative Dentistry and Endodontics
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• v.36 no.4
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• pp.290-299
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• 2011

Objectives: The usage of fluoride varnish for a moderate to low caries-risk group has not been well validated. This study aimed to evaluate the preventive and therapeutic efficacies of fluoride varnish on the initiated root caries. Materials and Methods: Ten premolars were sectioned into quarters, further divided into two windows, one of which was painted with Fluor Protector (1,000 ppm fluoride, Ivoclar Vivadent). An initial lesion with a well-preserved surface layer was produced by pH cycling. Scanned line analysis using energy dispersive spectrometry determined the weight percentages of Ca and P in the demineralized layer. Scanning Electron microscopy and confocal laser scanning microscopy (CLSM) evaluated the varnish-applied root surfaces. Results: The mean lesion depth (SD) was 12.3 (2.6) ${\mu}m$ (single cycling) and 19.6 (3.8) ${\mu}m$ (double cycling). Double cycling extended the lesion depth, but induced no more mineral loss than single cycling (p < 0.05). The mean weight percentages of Ca and P between groups with and without varnish were not significantly different (p < 0.05). A CLSM showed varnish remained within 15 ${\mu}m$ of the surface layer. Conclusions: When a mild acid challenge initiated root tissue demineralization, the application of low-concentration fluoride varnish did not influence the lesion depth or the mineral composition of the subsurface lesion.

• Journal of Korean Society of Transportation
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• v.24 no.5 s.91
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• pp.35-44
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• 2006

Acceleration and deceleration curves have been used for design purposes worldwide. The curve in design level has been regarded as an single deterministic curve to be used for design of climb lanes. It should be noted that the curve was originally made using ideal driving truck and that the curve is applied during design based on the assumption of no difference between ideal and real driving conditions. However. observations show that aged vehicles and lazy behavioring drivers nay make lower performance of vehicles than the ideal performance. The present paper provides the results of truck speeds at climbing lanes then probabilistic variation of acceleration and deceleration corves. For these purposes. a study about identification of vehicle makers, and weights for trucks at freeway toll gates and then observation of vehicle-following speed were performed. The 85%ile results obtained were compared with the deterministic performance curves of 180, 200, and 220 Ib/hp. It was identified that the performance of 85%ile results obtained from vehicle-following-speed observations were lower than one from deterministic performance curves. From these results, it may be concluded that at the beginning Point of climbing lanes additional $16.19{\sim}67.94m$ is necessary and that at the end point of climbing lanes $53.12{\sim}103.24m$ of extension is necessary.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.2
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• pp.190-199
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• 2019

$Carbopol^{(R)}$ 907 used as surface protecting agent in White's method is the one of the artificial caries lesion producing solution was discontinuing of production. New surface protecting material to substitute of $Carbopol^{(R)}$ 907 was required. The author prepared an artificial caries lesion producing solution as follows White's method with $Carbopol^{(R)}$ 907 and also another artificial caries lesion producing solution with $Carbopol^{(R)}$ $2050^{(R)}$. 96 flattened and polished enamel samples were immersed in a demineralizing solution of 0.1 mol/L lactic acid, 0.2% carboxyvinylpolymer and 50% saturated hydroxyapatite for 1, 2, 3, 4, 5, 6, 7, 9, 11, 15, 18 and 20 days. All samples from each group were subjected to polarized microscopy observed and image analysis for measuring the lesion depth. From the review of polarized images, the artificial caries lesion producing solution using $Carbopol^{(R)}$ 907 and $Carbopol^{(R)}$ 2050 can produced an artificial caries that was very similar to natural caries characters. From the regression analysis of the lesion depth produced by the artificial caries lesion producing solution using $Carbopol^{(R)}$ 907 and $Carbopol^{(R)}$ 2050, $Carbopol^{(R)}$ 2050 estimate as Y = 9.8X + 8.0 and $Carbopol^{(R)}$ 907 was Y = 8.4X - 0.4. R square value of $Carbopol^{(R)}$ 2050 and $Carbopol^{(R)}$ 907 was 0.965 and 0.945 respectively. The rate of demineralization by the artificial caries lesion producing solution using $Carbopol^{(R)}$ 2050 was faster than that of $Carbopol^{(R)}$ 907. And R square value of $Carbopol^{(R)}$ 2050 and $Carbopol^{(R)}$ 907 were very high and it means that the lesion depth was very high coefficient to demineralization period.

• Korean Journal of Heritage: History & Science
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• v.55 no.2
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• pp.168-184
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• 2022

This paper examined the construction techniques of the earthen fortifications in the Hanseong Period of Baekje Kingdom, which has been researched most frequently among the Three Kingdoms. The construction processes of the Earthen Fortifications were reviewed and dividing into 'selection of location and construction of the base', 'construction of the wall', and 'finish, extension and repair'. The results show that various techniques were mobilized for building these earthen fortifications. Techniques which were adequate for the topography were utilized for reinforcing the base, and several other techniques were used for constructing the wall. In particular, techniques for wall construction may be clearly divided into those of the fill(盛土) and panchuk(版築) techniques. The fill method has been assumed since the 2000s to have been more efficient than the panchuk technique. This method never uses the structure of the panchuk technique and is characterized by a complex soil layer line, an alternate fill, use of 'earth mound(土堤)'/'clay clod(土塊)', and junctions of oval fill units. The fill method allows us to understand active technological sharing and application among the embankment structures in the period of the Three Kingdoms. The panchuk technique is used to construct a wall using a stamped earthen structure. This technique is divided into types B1 and B2 according to the height, scale, and extension method of the structure. Type B1 precedes B2, which was introduced in the late Hanseong Period. Staring with the Pungnap Earthen Fortification in Seoul, the panchuk technique seems to have spread throughout South Korea. The techniques of the fill and panchuk techniques coexisted at the time when they appeared, but panchuk earthen fortifications gradually dominated. Both techniques have completely different methods for the soil layers, and they have opposite orders of construction. Accordingly, it is assumed that both have different technical systems. The construction techniques of the earthen fortifications began from the Hanseong Period of Baekje Kingdom and were handed down and developed until the Woongjin-Sabi Periods. In the process, it seems that there existed active interactions with other nations. Recently, since studies of the earthen fortifications have been increasing mainly in the southern areas, it is expected that comparative analysis with neighboring countries will be done intensively.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.5
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• pp.902-910
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• 2015

This study evaluated the qualitative properties of burdock (Arctium lappa L) peels as food material. Proximate composition, sweetness, pH, total acidity, mineral, fatty acid, free sugar, and organic acid contents of preprocessed burdock were measured. Crude ash, protein, fat, and total dietary fiber contents of non-peeled treated lotus roots were higher than those of peeled treated lotus roots (p<0.05). $^{\circ}Bx$, pH, and total acidity were not different in the peeling process. Redness and yellowness of lotus roots were reduced by the peeling process, whereas lightness increased (p<0.05). The mineral contents of Ca, K, Fe, and P were higher in non-peeled lotus roots, whereas non-peeled treated lotus root showed higher K contents (p<0.05). Maltose content was not significantly different, whereas fructose, sucrose and maltose contents were significantly different. Total organic acid contents were higher in non-peeled lotus roots (p<0.01). However total free amino acid contents were higher in peeled lotus roots (p<0.01).

• Journal of the Korea Concrete Institute
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• v.18 no.2 s.92
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• pp.161-168
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• 2006

An experimental investigation was conducted to examine the hysteretic behaviors of ultra-high strength concrete tied columns. The purpose of this study is to investigate the safety of ultra-high strength concrete columns with 100 MPa compressive strength for the requirement of ACI provisions. Eight 1/3 scaled columns were fabricated to simulate an 1/2 story of actual structural members with the cross section $300{\times}300mm$ and the aspect ratio 4. The main variables are axial load ratio, configurations and volumetric ratios of transverse reinforcement. The results show that the deformability of columns are affected by the configurations and volumetric ratios of transverse reinforcement. Especially, it has been found that the behavior of columns are affected by axial load ratio rather than the amounts and the configurations of transverse reinforcement. Consequently, to secure the ductile behavior of 100 MPa ultra-high strength concrete columns, ACI provisions for the requirement of transverse steel may considered axial load level and the details of transverse reinforcement.

• Korean Journal of Community Nutrition
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• v.12 no.1
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• pp.40-49
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• 2007

This study was done to investigate the health-related habits, dietary intakes and serum lipid levels in overweight and obese women by body mass index(BMI). Subjects were 137 pre-menopausal women aged 19 to 49 years. They were divided by 3 groups, overweight($23{\leqq}BMI<25$), obese($25{\leqq}BMI<30$) and morbidly obese($BMI{\geq}30$) according to their BMI. Body composition was determined by bioelectrical impedance analysis(BIA) method. Dietary intakes were examined by 3-day record method and nutrient intakes were analyzed by the Computer Aided Nutritional analysis program for professionals(CAN-pro 3.1). Serum lipid levels were measured using automatic biochemical analyzer(Selectra E). The average age, height weight and BMI of subjects were 31.7 years old, 159.3cm, 69.4kg, and $27.4kg/m^2$, respectively. Their average consumption of energy were 1712kca1 and 86.4% of estimated energy requirement(EER). Their mom ratio of carbohydrate:protein:fat was 55.2:14.6:30.2. Particularly, the fat consumption of subjects tended to be elevated with increasing BMI. There was no significant difference in nutrient intakes among 3 groups. But the mom intakes of Ca, Fe, vitamin C and Na of all the subjects were 70.1%, 81.2%, 75.7% of recommended intake(RI) and 258.9% of adequate intake(AI), respectively, The intakes of vegetables and seaweeds were significantly higher in morbidly obese group while the intake of fruits was higher in overweight group compared to the other groups. Serum lipid analysis showed that there were no significant differences in the levels of total cholesterol, triglyceride and LDL-cholesterol among the groups. But the serum HDL-cholesterol level of the overweight group was significantly higher than that of the other groups. LDL-/HDL-cholesterol ratio and AI index were significantly higher in the morbidly obese group compared to the other groups. In addition, The systolic blood pressure of morbidly obese group was significantly higher compared to the other groups. Overall data suggest that morbidly obese women have to more concern about reducing systolic blood pressure and nm lipid levels by decreasing their fat consumption and salt intakes as well as loosing body fat. In addition, all the subjects participated in this study have to be careful about their meals and health-related behaviors in order to prevent obesity-related chronic diseases.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.1
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• pp.11-19
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• 2017

The purpose of the study was to investigate the distribution of primary fused teeth and identify the correlation between primary fused teeth and their effect on permanent dentition. 2575 children between the age of 4 and 6 in Kyungpook National University Hospital from January 2009 to August 2015 were investigated. A total of 84 children (46 boys and 38 girls) had fused teeth. 14 of these children had two fused teeth. Prevalence of caries involvement was in 65% of maxilla and 6% of mandible. Prevalence of permanent successors missing was 86.3% in the cases involving maxillary central and lateral incisor, 70% in mandibular lateral incisor and cuspid, 11.7% in mandibular central and lateral incisor. 27 of 84 children (32.1%) had supernumerary teeth. The highest prevalence rate is seen in the cases involving maxillary central and lateral incisor. Delayed permanent tooth eruption was only observed in the maxilla because of developing supernumerary tooth. Early diagnosis of fused tooth in the primary dentition can allow the dentist to make treatment plan at the appropriate time in accordance with the tooth arrangement and tooth development.

• Korean Journal of Food Science and Technology
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• v.15 no.1
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• pp.19-26
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• 1983

A study was designed to investigate the sorption characteristics of binary mixtures of NaCl and sucrose or glucose stored at various relative humidities ranging from 46% to 92%. At low relative humidity below RH 65%, the sorption equilibrium was easily achieved, whereas at higher relative humidity values over 73%, all of the mixtures tended to cintinously absorb moisture with increase in storage time. A linear equation of log $({\frac{dw}{dt}})$ = a log(t) + log(b) was found to be valid between the sorption rate and storage time with respect to storage humidities. In sucrose-NaCl mixture, the slope showed a increasing tendency as the percentage of NaCl increased in the mixture, while that of glucose-NaCl mixture failed to show a definite trend. Plateaus were obtained when the amount of water absorbed was plotted on the X axis and the percent composition of mixture on the Y axis at different storage time. The shape of plateau was varied with respect to the kind of sugar-NaCl mixture, composition of the mixture and relative humidities. A linearity was found between log(1-Aw) and the amount of water absorbed over the Aw range 0.73-0.92 and the slope was affected by the kind and composition of sugar-NaCl mixtures.

• Proceedings of the Korean DIstribution Association Conference
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• 2001.11b
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• pp.145-163
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• 2001

최근 인터넷 상거래가 급속히 확산되면서 기업의 경쟁이 실물세계와 가상세계에서 발생하는 현상이 전개되고 있다. 즉, 유통경로의 측면에서 볼 때 기존의 물리적 세계에 존재하는 전통적인(오프라인) 유통경로와 사이버공간에 존재하는 가상(온라인) 유통경로가 서로 경쟁하는 형국이 벌어지고 있는 것이다. 유통경로간 경쟁의 중심부에는 고객이 자리잡고 있다. 어떤 경로든 소비자의 욕구를 정확히 파악하고, 이들에게 최상의 유통서비스를 제공하는 경로는 생존·번영할 수 있을 것이다. 사실 현재 진행되고 있는 논의들과 현상들을 볼 때, 어느 한 유통경로가 다른 유통경로를 완전히 대체하는 제로섬 게임의 양상은 나타나고 있지 않다. 즉, 상당기간 두 유통경로는 상호 병존할 것으로 보인다. 본 연구는 이러한 점에 초점을 맞추어 이들 두 경로가 자신들만의 차별화된 경쟁우위를 가지고 생존할 수 있는 마케팅전략을 구상하기 위해 시도되었다. 이러한 전략을 제시하기 위해서는 우선 이들 두 경로상에서 소비자의 구매(쇼핑)행동은 어떻게 다른가에 대한 비교연구가 선행되어야 할 것이다. 본 연구는 온라인 유통경로와 오프라인 유통경로에서 소비자 구매행동의 차이를 비교분석 하는데 그 목적을 두고 있다. 특히 제품유형별로 온라인과 오프라인에서 구매속성중요도가 어떻게 달라지는가를 확인. 검증해 보기 위해 시도되었다. 캐주얼의류, 여행상품, 음악CD를 가지고 인터넷 사용자 500명을 대상으로 온라인조사를 실시한 결과, 온라인과 오프라인에서 구매속성 중요도에는 유의한 차이가 나타났다. 이 결과를 토대로 오프라인 매장과 온라인 매장이 어떻게 차별화해야 하는가에 대한 시사점을 제시하였다.통계적인 차이가 있었다(P<0.05). 계육내 CLAisomer는 1, 2, 3% 급여구에서 각각 12.23, 18.74, 25.67 mg/g으로 처리구간에 현저한 차이를 보였다(P<0.05). 본 연구의 결과 CLA의 급여는 SBO와 CT에 비하여 증체량을 개선하고 혈중HDL을 높여주는 경향을 보였지만 ND항체가는 개선되지 못하였다.으며, 그 효과는 농도에 의존적이었다, 고콜레스테롤 투여군(HC)의 분변 중 총 지질과 중성지방 농도는 정상대조군(C)에 비해 다소 높았고, 총 콜레스테롤의 경우는 유의적으로 높게 나타났다. 그러나 뽕잎첨가군(HC5M과 HC10M)의 총 지질, 중성지방 및 콜레스테롤 농도는 콜레스테롤 투여군(HC)에 비해 분변으로 배설량이 증가하는 현상을 보였다. 이상의 결과를 살펴보면 뽕잎 분말은 고콜레스테롤식이를 섭취하는 경우 혈청과 간장의 지질수준은 떨어뜨리고, 분변중 지질배설량을 상승시키는 효과가 현저한 것으로 보인다.둘째. 1990년대 한국과 미국 패션시장의 가격과 품질간의 상관계수의 범위는 제품군별. 산업범주별 로 상이한 분포를 보이고 있었다. 패션제품군별로 보 면, 한국의 경우는 가장 높은 '여행용가방(r = 0.707)' 에서 가장 낮은 '자외선 차단화장품(r = -0.58)'까지, 그리고 미국 패션제품군의 상관계수의 범위는 '팬티 스타킹'의 0.820에서 '남성용 런닝슈즈'의 -0.472까지의 분포를 나타냈다. 마지막으로, 제품의 가격과 품질에 대한 정보를 소비자가 알 경우 얻을 수 있는 소비자의 구매이득 을 추산한 결과 패션제품시장에서 완전한 품질정보를 가지고 있다고 가정한 '현명한 사람'은, 최고가격의 제품만을