• International Journal of Oral Biology
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• v.46 no.4
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• pp.184-189
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• 2021

When luting indirect restorations with dual-cure resin cement (DCRC), excess cement can be easily removed by performing tack cure of DCRC for a few seconds. The purpose of this study was to evaluate whether different tack cure times affect polymerization shrinkage (PS) of the selected DCRC. One dual-cure resin cement (G-CEM LinkAce, GC) was used for measuring PS in light-cure (LC group), self-cure (SC group), and two tack-cure modes. In the first tack-cure subgroup, tack cure was performed for 1, 2, 3, and 5 seconds, followed by light cure after 2 minutes of remnant removal time in each case (TC-LC groups). In the other tack-cure subgroup, tack cure was performed for the same lengths of time, but followed by self-cure in each case (TC-SC groups). PS was measured by a modified bonded disc method for 1,800 seconds. One-way analysis of variance followed by Duncan's post hoc test was used to determine any statistically significant differences among the test groups (α = 0.05). When the DCRC was self-cured after tack cure, PS was significantly lower than when it was only self-cured (p < 0.05); however, tack cure time did not affect PS (p > 0.05). When the DCRC was light-cured, PS was not affected by tack cure or tack cure time (p > 0.05). Therefore, tack cure within 5 seconds did not negatively affect the final PS when the DCRC was light-cured after cement remnant removal.

• Korean Journal of Environmental Agriculture
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• v.42 no.2
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• pp.131-138
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• 2023

The biological half-life and dissipation rate of azoxystrobin in crown daisy were calculated to establish the pre-harvest residue limits (PHRLs). The pesticide residues were calculated after washing with five different processes to propose an effective process in the household and conducted a risk assessment to confirm dietary safety. Azoxystrobin was sprayed according to the critical good agricultural practices (cGAP) in two different field trials, and the samples were harvested 7 times. The limit of quantitation was 0.02 mg/kg, and the mean recoveries of azoxystrobin were within the range of 70~120% with below 20% coefficient variation at the concentration of 0.02 and 0.2 mg/kg . The biological half-lives were 7.4 and 4.7 days, and the dissipation rate constants were 0.0872 and 0.1217 in fields 1 and 2, respectively. The average removal rates were 58.13~78.13% by the different washing processes, and there were significant differences between the washing processes (one-way ANOVA analysis and post-hoc Duncan test, p-value<0.05). The residues of azoxystrobin in crown daisy were safe levels from farm to fork after application with the critical good agricultural practice (cGAP) registered in Korea.

• The korean journal of orthodontics
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• v.32 no.6 s.95
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• pp.401-411
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• 2002

Precise bracket positioning is essential in modem orthodontics. However, there can be alterations in the vertical position of a bracket due to several reasons. The purpose of this study was to evaluate the effect of variations in the vertical bracket position on the crown inclination in Korean patients with normal occlusion. From a larger group of what was considered to be normal occlusions obtained from the Department of Orthodontics, College of Dentistry, Seoul National University, each of the final 10 subjects (6 males and 4 females, with an average age of 22.3 yews) was selected. The dental models of each of the subjects were scanned three-dimensionally by a laser scanner, and measurements drawn from these were made on the scanned dental casts of the subjects were input into the computer program. From this the occlusal plane and the bracket plane were determined. The tooth plane was then constructed to measure the crown inclination on the bracket plane of each tooth. From a practical standpoint, information was obtained on the extent to which the torque of a tooth would be changed as the bracket position was to be moved vertically (in ${\pm}0.5mm,\;{\pm}1.0mm,\;{\pm}1.5mm$) from its ideal position. A one way analysis of the variance (ANOVA) was used to compare each group of the different vertical distances from the bracket plane on a specific tooth. Duncan's multiple comparison test was then performed. There were statistically significant differences in the crown inclination among the groups of different vertical distances for the upper central incisor, upper lateral incisor, upper canine, upper first and second molars, lower first and second premolars, and lower first and second molars (p<0.05). On the upper anterior teeth, upper molars, lower premolars and lower molars, the resultant torque values due to the vertical displacement of the bracket were different depending on the direction of the displacement, occlusal or gingival. This study implies that the torque of these teeth should be handled carefully during the orthodontic treatment. In circumstances in which the bracket must be positioned more gingivally or occlusally due to various reasons, it would be useful to provide the chart of torque alteration of each tooth referred to in this study with its specified bracket prescription.

• Korean Journal of Food Science and Technology
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• v.5 no.1
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• pp.16-24
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• 1973

Breads were made from composite flours based on domestic resources and their quality was assessed to obtain the following results. 1) When barley bread was made according to the formula for standard wheat bread, its specific loaf volume (SLV) was quite low (1.3 at 100% addition of water) in comparison with 3.3 for wheat bread. Addition of 10% defatted soy flour increased its SLV to 1.7 (at 100% water). Among various flour-improving additives, the use of 1.5% GMS + 0.5% CSL gave best results (SLV: 2.0 at 100% water). Admixture of wheat flour with the composite flour based on barley was most effective. Replacement of barley flour with 25% wheat flour gave SLV of 2.8 (at 90% water) and that with 50% wheat flour gave SLV of 3.2 (at 90% water), comparable to standard wheat bread with respect to loaf volume, color and texture. 2) Sweet potato bread had the characteristics of turning black-brown on baking. Use of 20% defatted soy flour and GMS + CSL gave higher SLV (1.9 at 100% water). Addition of wheat flour at 25% or 50% level to the composite flour based on sweet potato flour gave SLV of 2.3 and 2.6, respectively, at 90% water and its color and texture were improved 3) Potato flour was different from sweet potato flour in baking, the effect of GMS + CSL being quite low. Bread from corn flour was different from barley flour bread and defatted rice bran was not suitable for bread-making. 4) Bread was made from following composite flours based on naked barley and sweet potato flours along with the use of proper additives: (a) naked barley flour + defatted soy flour + wheat flour (45 : 10 : 45) (b) naked barley flour + defatted soy flour + wheat flour (67 : 10 : 23) (c) naked barley flour + defatted soy flour (90 : 10) (d) sweet potato flour + defatted soy flour + wheat flour (40 : 20 : 40) (e) sweet potato flour + defatted soy flour (60 : 20 : 20) Sensory evaluation of above breads in comparison with standard wheat bread (So) gave the following decreasing order of scores, So>(a)>(b)>(c)>(e)>(d) and Duncan's multiple range test showed that bread (a) was not different from standard wheat bread significantly at 5% level, in overall evaluation including color, texture, taste and flavor.

• Korean Journal of Applied Biomechanics
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• v.17 no.2
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• pp.177-185
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• 2007

Even though there were no clear definitions of the short game and short game distance, short game capability is crucial for a good golf score. Generally, chip shot and pitch shot are regarded as two principal components of the short game. Chip shot is a short, low trajectory shot played to the green or from trouble back into play. Pitch shot is a high trajectory shot of short length. Biomechanical studies were conducted usually to analyze full swing and putting motions. The purpose of the study was to reveal the kinematical differences between professional golfers' 30 yard $53^{\circ}wedge$ chip shot and $56^{\circ}wedge$ pitch shot motions. Fifteen male professional golfers were recruited for the study. Kinematical data were collected by the 60 Hz three-dimensional motion analysis system. Statistical comparisons were made by paired t-test, ANOVA, and Duncan of the SPSS 12.0K with the $\alpha$ value of .05. Results show that both the left hand and the ball were placed left of the center of the left and right foot at address. The left hand position of the chip shot was significantly left side of that of the pitch shot. But the ball position of the pitch shot was significantly right side of that of the chip shot. All body segments aligned to the left of the target line, open, at address. Except shoulder, there were no significant pelvis, knee, and feet alignment differences between chip shot and pitch shot. These differences at address seem for the ball height control. Pitch shot swing motions(the shoulder and pelvis rotation and the club head travel distance) were significantly bigger than those of the chip shot. Club head velocity of the pitch shot was significantly faster than that of the chip shot at the moment of impact. This was for the same shot length control with different lofted clubs. Swing motion differences seem mainly caused by the same shot length control with different ball height control.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.10-10
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• 2001

본 연구는 정자의 기능검사와 체외수정을 실시하여 수정능력과 수태율의 예측을 위한 이들간의 상관관계를 알아보기 위하여 AI 중인 8두의 종모돈을 가지고 시도되었다. 정자의 기능검사로서 첨체상태는 spermac stain을 이용하여 관찰하였고 정자원형질막의 온전성(integrity) 검사로는 hypo-osmotic test(HOST)를 실시하였다. 그리고 정자의 첨체효소인 acrosin activity를 측정하였다. 체외수정율은 체외성숙 난포란과 실시하였다. 8마리 종모돈의 첨체형태의 정상비율은 처리전 64.7-81.9%, 처리후 21.8~48.1%로 개체간의 유의성이 있었다. Acrosin activity는 처리전 3.70-4.57 mIU/$10^{6}$ 정자, 처리후 3.23~5.53 mIU/$10^{6}$ 정자였으며 처리전 개체에서만 유의성이 있었다. HOST는 처리전 26.5~54.5%, 처리후 20.2~50.0%로서 처리전후간의 차이는 없었지만 개체간의 유의차는 있었다. 체외수정율의 범위는 61.6~8l% 였고 6일 후 배발달율(배반포율)은 11~22%로 개체간의 유의성이 있었다. Spearman ranking correlation에서 체외수정율은 첨체상태검사와는 0.45, HOST와는 0.43로서 유의성이 인정되지 않았다. 또한 수태율은 첨체상태검사와 0.89, acrosin activity와 0.86, HOST와 0.86, 체외수정과 0.51로서 유의적으로 높은 상관관계를 나타내었다. 본 결과에서 종모돈의 기능검사와 체외수정결과로 개체간의 수정능력의 차이를 알 수 있었으나 수정란의 발달율이나 수태율을 예측할 수 있을 만큼의 상관성은 얻지 못했다. 정자검사에 있어서 일반성상 검사외에 정자기능 검사의 추가 실시가 종모돈 정자의 정확한 수정능력을 예측하는데 필요할 것이다.llus kawachii등으로 담금하여 제조한 술 시료 11종류를 대상으로 하여 쓴맛, 미묘한 맛, 떫은 맛, 신맛, 좋은 맛의 정도를 5단계로 나누어 관능검사를 실시한 다음 자료를 Duncan's multiple range test로 분석한 결과 전체적으로 좋은 맛에 대한 기호도는 Aspergillus sp. SH-607 시료와 Aspergillus sp. SH-412, Rhizopus sp. SH-606, Aspergillus sp. SH-613, Rhizopus sp. SH-654, Aspergillus sp. SH-696 Aspergillus kawachii 시료가 유의성 있게 좋은 맛을 나타내 기호도가 높았으며 맛과 기호도가 가장 좋았던 것은 Aspergillus sp. SH-607 시료로 나타났다.\varepsilon}}$는 268.20 $m^2$/day, $T_{ηη}$는 28.75 $m^2$/day이고 주 텐서방향은 N7.55$^{\circ}$E이며 BH-5호공에서의 $T_{{\varepsilon}{\varepsilon}}$는 168.40 $m^2$/day, $T_{ηη}$는 66.80 $m^2$/day이고 주 텐서방향은 N76.59$^{\circ}$E로 나타났다. 이처럼 연구지역에서의 각각의 공에 대한 투수량계수텐서는 서로 다르게 나타났으며 이에 따른 주 텐서방향도 서로 다름을 알 수 있다.. Targeting a 10% recycling rate for municipal waste in 2001. EPA plans to research and develop new recycling techniques, expand t

• The Journal of Advanced Prosthodontics
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• v.9 no.5
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• pp.341-349
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• 2017

PURPOSE. This study evaluated the accuracies of different bite registration techniques for implant-fixed prostheses using three dimensional file analysis. MATERIALS AND METHODS. Implant fixtures were placed on the mandibular right second premolar, and the first and second molar in a polyurethane model. Aluwax (A), Pattern Resin (P), and Blu-Mousse (B) were used as the bite registration materials on the healing abutments (H) or temporary abutments (T). The groups were classified into HA, HP, HB, TA, TP, and TB according to each combination. The group using the bite impression coping was the BC group; impression taking and bite registration were performed simultaneously. After impression and bite taking, the scan bodies were connected to the lab analogs of the casts. These casts were scanned using a model scanner. The distances between two reference points in three-dimensional files were measured in each group. One-way ANOVA and Duncan's test were used at the 5% significance level. RESULTS. The smallest distance discrepancy was observed in the TB group using the temporary abutments. The Blu-Mousse and HP groups showed the largest distance discrepancy. The TB and BC groups showed a lower distance discrepancy than the HP group (P=.001), and there was no significant difference between the groups using the temporary abutments and healing abutments (P>.05). CONCLUSION. Although this study has limitations as an in-vitro investigation, the groups using the temporary abutments to hold the Blu-Mousse record and bite impression coping showed greater accuracy than the group using the healing abutments to hold the pattern resin record.

• The Journal of Advanced Prosthodontics
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• v.9 no.4
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• pp.315-320
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• 2017

PURPOSE. The aim of this investigation was to analyze the dimensions of clinical crowns and to classify the crown and the gingival type in the anterior teeth in Korean young adults. MATERIALS AND METHODS. Casts were obtained from 50 subjects ranging in age from 24 to 32. Measurements of length and width were made on the casts using a pair of digital calipers on the entire dentition. Crown thickness and papilla height were also measured and MDW/CL (mesiodistal width to clinical length) and CW/CL (cervical width to clinical length) ratios of the maxillary anterior teeth were calculated. The K-clustering method was used for CW/CL to classify the anterior tooth shape into three groups (tapered, ovoid, and square), and one-way analysis of variance and Duncan's post-hoc comparison were used to evaluate statistical significance between the groups. Pearson's correlation analysis was performed between tooth shape and papillary height (PH) to demonstrate the correlation between tooth shape and gingival morphological characteristics. RESULTS. The average length of the maxillary central incisors was 9.89 mm; the mesio-distal width was 8.54 mm; and the ratio of width/length was 0.86 in Korean young adults. The average bucco-palatal thickness of the central incisor was 3.14 mm at the incisal 1/3 aspect. Ovoid type was the most common tooth shape (48%), followed by square type (29%) and taper type (23%) in the central incisors of Korean young adults. Tooth shape and gingival type were correlated with each other. CONCLUSION. New reference data were established for tooth size in Korean young adults and the data show several patterns of tooth shape and gingival type. Clinicians should diagnose and treat based on these characteristics for better results in the Korean population.

• Journal of Global Scholars of Marketing Science
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• v.15 no.1
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• pp.41-60
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• 2005

The purposes of this study were 1)to examine the conceptual structure of purchasing motives and information seeking of beauty service, 2)to find out the effects of purchasing motives on information seeking, and 3)to investigate the differences of purchasing motives and information seeking according to the demographic variables. The questionnaire was developed based on pretest and previous studies, and completed by 331 female consumers living in Seoul and Busan. Data were analyzed by factor analysis, Cronbach's a, regression analysis, Pearson's correlation, ANOVA, and Duncan test. The results are as follows; First, factor analysis showed that the purchasing motives of beauty services consisted of five factors, such as Fashionableness, Impulse purchase, Special event, Mood & Recreation, and Practical purchasing needs. And the information seeking for beauty services consisted of four factors, such as Mass media, Opinions of neighbors, Experience & Observation, and Sales hook. Second, mass media was effected by fashionableness, impulse purchase, special event, and mood & recreation. Experience & Observation was effected by fashionableness, special event, and mood & recreation. Sales hook was effected by fashionableness, and impulse purchase. Third, the dimensions of purchasing motives and information seeking of beauty service were significantly different according to age, marriage or unmarried, and duties.

• Restorative Dentistry and Endodontics
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• v.29 no.4
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• pp.386-398
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• 2004

Objectives: The purpose of this study was to observe the reaction kinetics and the degree of polymerization of composite resins when cured by different light sources and to evaluate the effectiveness of the blue Light Emitting Diode Light Curing Units (LED LCUs) compared with conventional halogen LCUs. Materials and Methods: First, thermal analysis was performed by a differential scanning calorimeter (DSC). The LED LCU (Elipar Freelight, $320{\;}mW/\textrm{cm}^2$) and the conventional halogen LCU (XL3000, $400{\;}mV/\textrm{cm}^2$) were used in this study for curing three composite resins (SureFil, Z-250 and AEliteFLO). Second. the degree of conversion was obtained in the composite resins cured according to the above curing mode with a FTIR. Third, the measurements of depth of cure were carried out in accordance with ISO 4049 standards. Statistical analysis was performed by two-way ANOVA test at 95% levels of confidence and Duncan's procedure for multiple comparisons. Results: The heat of cure was not statistically different among the LCUs (p > 0.05). The composites cured by the LED (Exp) LCUs were statistically more slowly polymerized than by the halogen LCU and the LED (Std) LCU (p < 0.05). The composite resin groups cured by the LED (Exp) LCUs had significantly greater degree of conversion value than by the halogen LCU and the LED (Std) LCU (p =0.0002). The composite resin groups cured by the LED (Std) LCUs showed significantly greater depth of cure value than by the halogen LCU and the LED (Exp) LCU (p < 0.05).