• Journal of the Korean Dietetic Association
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• v.15 no.3
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• pp.278-285
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• 2009

The purpose of this pilot study was to examine the feasibility of using digital pictures to assess individuals' nutrient intakes from school lunch. The subjects for the study were 29 male students and 40 female students from two classes in a middle school located in Daejeon Metropolitan City, Korea. The school lunch service was self-operated and the students were allowed to portion the foods by themselves. The teacher in charge of each class took digital pictures of every student's lunch plate that was tagged with an i.d. number, before and after eating for two consecutive days. The researchers estimated the amount of food, which an individual actually consumed by comparing pre- and post-pictures of their plate with reference food pictures for better visual estimation of the food amounts. Individual energy and nutrient intakes were calculated using CAN-Pro (ver 3.0) using the food intake data visually estimated from the digital pictures and school lunch recipes. The teachers in charge reported that about 10~15 additional minutes were needed to take the pictures used for the study and this additional time did not place much burden on the service process during the lunch period. The results showed that the students' actual energy and nutrient intakes from the same school lunch menus were quite varied as the serving portions were not regulated and left-overs were not prohibited. This pilot study suggests that examination of individual nutrient intake using digital picture is a feasible method in the context of school lunch service.

• Journal of Periodontal and Implant Science
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• v.41 no.5
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• pp.253-258
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• 2011

Purpose: Immediate implantation presents challenges regarding site healing, osseointegration, and obtaining complete soft-tissue coverage of the extraction socket, especially in the posterior area. This last issue is addressed herein using the double-membrane (collagen membrane+high-density polytetrafluoroethylene [dPTFE] membrane) technique in two clinical cases of posterior immediate implant placement. Methods: An implant was placed immediately after atraumatically extracting the maxillary posterior tooth. The gap between the coronal portion of the fixture and the adjacent bony walls was filled with allograft material. In addition, a collagen membrane (lower) and dPTFE membrane (upper) were placed in a layer-by-layer manner to enable the closure of the extraction socket without a primary flap closure, thus facilitating the preservation of keratinized mucosa. The upper dPTFE membrane was left exposed for 4 weeks, after which the membrane was gently removed using forceps without flap elevation. Results: There was considerable plaque deposition on the outer surface of the dPTFE membrane but not on the inner surface. Moreover, scanning electron microscopy of the removed membrane revealed only a small amount of bacteria on the inner surface of the membrane. The peri-implant tissue was favorable both clinically and radiographically after a conventional dental-implant healing period. Conclusions: Secondary closure of the extraction socket and immediate guided bone regeneration using the double-membrane technique may produce a good clinical outcome after immediate placement of a dental implant in the posterior area.

• Journal of Korean Society for Atmospheric Environment
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• v.17 no.E3
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• pp.91-99
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• 2001

Plasma reactor was used to generate a high potential difference between two surfaces of concentric pyrex tubes by electrical current. The annular gap of the reactor was calculated by trial and error from the breakdown voltage equation and set at 0.45 cm. The overall objective of this research was to know the effects of the frequency, humidity, and residence time on the formation of nitrogen oxides in a plasma reactor. The primary voltage varied from 50 to 90 volts and the frequency was varied in increments of 10 Hz from 60 to 650 Hz at the primary voltage of 90. The increase in the secondary voltage was not linear but exponential at high frequencies. At a maximum concentration of about 745 ppm, the frequency and secondary voltage was 600 Hz and 4,200 volts, respectively. All tests for the effects of humidity on NO$_{x}$ production were performed at the optimal setting of 90 colts and 600 Hz frequency. Since the NO$_{x}$ production was not an one dimensional phenomenon, competing reactions were assumed to occur in the discharge chamber. The sharp peak concentration of 1,810 ppm was observed at 38% of relative humidity, The enhanced production was choked off, and the production rate rapidly dropped to 3 ppm at above 40% of relative humidity. It is assumed that the corona attacks the most vulnerable molecules in the reaction chamber before attacking other more lightly bonded molecules, possibly at humidities above 38% and the optimized 90 volt setting. Thus, there was not enough energy left after attacking all water molecules to decompose an appreciable amount of $N_2$. If nitrogen breakdown does not occur, then oxides of nitrogen are not likely to be produced.ced.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.5
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• pp.589-596
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• 2021

In this study, the optimum gating system was designed, and the two zinc alloy worm gears were manufactured in single process by applying a symmetrical gating system with 2 runners. The SRG ratio is set to 1 : 0.9 : 0.6, and the cross-sectional shapes such as sprue, runner and gate are designed. In order to determine whether the design of the gating system is appropriate, casting analysis was carried out. It takes 4.380 s to charge the casting 100%, 0.55 to 0.6 m/s at the gates and solidification begins after the casting is fully charged. The amount of air entrapment is 2% in the left gear and 6% in the right gear. Hot spots occurred in the center hole of the gear, and pores were found to occur around the upper part of the hole. Therefore, the design of the casting method is suitable for worm gears. CT analysis showed that all parts of worm gear were distributed with fine pores and some coarse pores were distributed around the central hole of worm gear. The yield strength and tensile strength were 220 MPa, 285 MPa, and the elongation rate was 8%. Vickers hardness is 82 HV.

• The korean journal of orthodontics
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• v.51 no.3
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• pp.157-165
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• 2021

Objective: This study aimed to identify the clinical effectiveness of two different penetration depths of micro-osteoperforations (MOPs) on the rate of orthodontic tooth movement. Methods: Twenty-four patients requiring the removal of the upper first premolar teeth were selected and randomly divided into two groups. The control group participants did not undergo MOPs. Participants in the experimental group underwent three MOPs each at 4-mm (MOP-4) and 7-mm (MOP-7) depths, which were randomly and equally performed to either the left or right side distal to the canine. The retraction amount was measured on three-dimensional digital models on the 28th day of retraction. MOP-related pain was measured using a visual analog scale (VAS). Between-group statistical differences in the VAS scores were determined using an independent t-test and those in canine retraction were determined using analysis of variance and post-hoc Tukey test. Results: No significant difference was found between the MOP-4 (1.22 ± 0.29 mm/month) and MOP-7 (1.29 ± 0.31 mm/month) groups in terms of the canine retraction rate. Moreover, both the groups demonstrated a significantly higher canine movement than the control group (0.88 ± 0.19 mm/month). MOPs did not significantly affect the mesialization of the posterior teeth (p > 0.05). Moreover, the pain scores in the MOP-4 and MOP-7 groups were similar and showed no statistically significant difference. Conclusions: Three MOPs with a depth of 4 mm can be performed as an effective method to increase the rate of tooth movement. However, three MOPs with depths of 4-7 mm does not additionally enhance tooth movement.

• The korean journal of orthodontics
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• v.30 no.1 s.78
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• pp.9-17
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• 2000

This study was performed to compare and analyze the mode of tooth movement according to the timing of orthodontic force application alter extraction. The upper right and left third incisors were carefully extracted at three-week interval in lout adult dogs. Both canines were used as an anchorage for the bodily movement of the upper second incisors. Orthodontic forte of 100 gm was simultaneously applied at one week after extraction on one side and four weeks after extraction on the other side using NiTi closed coil spring. While orthodontic force was applied for twelve weeks, the amount of tooth movement was measured at every second week with digital calipers. The animals were sacrificed at twelve weeks and histologic examination was executed to reveal any difference between both sides. The results were obtained as follows. 1. The tooth movement was likely to be faster in lout-week side 4han one-week side for the first two weeks while faster in one-week side during next two weeks 2. The rate of tooth movement was fastest during four to six weeks period, then decreased gradually. 3. The total amount of tooth movement was likely to be larger in one-week side compared to four-week side. 4. Any damage to tooth and periodontal tissue could not be seen in the histologic section of one-week side. These results suggest that earlier application of orthodontic force is better than later after extraction In terms of the rate of tooth movement.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.5
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• pp.512-520
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• 2017

This study was carried out to develop concentrate of residual jujube flesh around the seed as a thickening agent of Bulgogi sauce. Quality characteristics and sensory test of Bulgogi sauces added with jujube concentrate (30%, 35%, 40%, 45%, 50%) were evaluated in comparison with control sauce containing xanthan gum as a thickening agent. Moisture content of Bulgogi sauce added with 30% jujube concentrate was the highest (74.59%). As content of jujube concentrate increased, moisture contents in Bulgogi sauces significantly decreased. Sugar content of control sauce ($30.82^{\circ}Bx$), was lowest among the sauces. As content of jujube concentrate increased, Sugar content of sauces significantly increased ($33.00{\sim}34.38^{\circ}Bx$). Salinity (%) was highest in control sauce (1.38%), and there was no difference in salinity among the sauces depending on the amount of jujube concentrate. Viscosity was highest in sauce added with 50% jujube concentrate (43.33 cP) and lowest in sauce with 30% jujube concentrate (13.20 cP). As content of jujube concentrate increased, viscosity tended to increase significantly. Spreadability was highest in sauce added with 30% jujube concentrate (8.88 cm). As the amount of jujube concentrate increased, spreadability of sauce tended to decrease significantly. Color value was different according to the contents of jujube concentrate in sauces. L-, a-, and b-values of control sauce were highest at 40.19, 1.5, and 24.57, respectively. The results of the sensory test for Bulgogi sauce showed that overall preference was significantly highest in sauce added with 35% jujube concentrate. Moreover, sauce added with 35% jujube concentrate was preferred the most in terms of appearance, taste, and fluidity. Meanwhile, the results of the differentiation test showed a significant difference in color intensity, jujube flavor and taste, sweet taste, and salty taste. However, no significant difference was observed in fluidity. The results of the preference test for Bulgogi seasoned with sauces added with jujube concentrate showed that overall preference and flavor, taste, and texture preference were highest in Bulgogi seasoned with sauce added with 35% jujube concentrate. However, no significant difference was observed in preference towards appearance among the samples.

• Journal of Sensor Science and Technology
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• v.26 no.1
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• pp.15-23
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• 2017

In this study, bioelectrical impedance analysis, which has been used to assess an alteration in intracellular fluid (ICF) of the body, was applied to detect intravenous infiltration. The experimental results are described as follows. Firstly, when infiltration occurred, the resistance gradually decreased with time and frequency i.e., the resistance decreased with increasing time, proportional to the amount of infiltrated intravenous (IV) solution. At each frequency, the resistance gradually decreased with time, indicating the IV solution (also blood) accumulated in the extracellular fluid (ECF) (including interstitial fluid). Secondly, the resistance ratio started to increase at infiltration, showing the highest value after 1.4 min of infiltration, and gradually decreased thereafter. Thirdly, the impedance ($Z_C$) of cell membrane decreased significantly (especially at 50 kHz) during infiltration and gradually decreased thereafter. Fourthly, Cole-Cole plot indicated that the positions of (R, $X_C$) shifted toward left owing to infiltration, reflecting the IV solution accumulated in the ECF. The resistance ($R_0$) at zero frequency decreased continuously over time, indicating that it is a vital impedance parameter capable of detecting early infiltration during IV infusion. Finally, the mechanism of the current flowing through the ECF, cell membrane, and ICF in the subcutaneous tissues was analyzed as a function of time before and after infiltration, using an equivalent circuit model of the human cell. In conclusion, it was confirmed that the infiltration could be detected early using these impedance parameters during the infusion of IV solution.

• Quality Improvement in Health Care
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• v.19 no.2
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• pp.80-88
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• 2013

Objectives: With the increase in the number of people who are marginalized in receiving medical services, the role of Seoul National University Hospital as a public hospital is being emphasized. However, many patients are either experiencing delays in receiving medical services or simply being left out as a result of the inaccessibility to the department of social work on part of both the patients and the medical staff. Methods: In order to increase consultation from other departments and the accessibility to the department of social work for the socially marginalized group through early consultation from other departments, the following steps were taken. First, an orientation program for novice medical residents led by clinical social worker was introduced/implemented. Second, posters and brochures on various financial aids programs were produced and distributed. Third, a system of early screening was built/constructed, and once a week rounds and early screening meeting were executed/carried out. Result: The department of social work's rate of consultation from other departments increased by 4.4% compared to last year, while it showed 61% increase for those wards that had an early screening meeting. In addition, the average time of consultation from other departments was reduced by 3.1 days, securing sufficient amount of time for clinical social work services, both in terms of quality and quantity. Conclusion: It is believed that the various promotional activities, along with the strengthening of accessibility to clinical social work services and early consultation on part of social disadvantaged/marginalized group, would undoubtedly help provide quality services to patients and increase their level of satisfaction. In this way, the wards can effectively reduce the number of unnecessary hospital stay days while the hospital can prevent the accumulation of outstanding bills/fees as well as contribute to the publicness of hospitals. The promotion of clinical social work programs in various ways are crucial to ensuring the satisfaction of patients and hospital staff.

• The korean journal of orthodontics
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• v.50 no.2
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• pp.75-85
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• 2020

Objective: The aim of this study was to evaluate changes in the nasal soft tissues, including movements of landmarks, changes in linear distances, and volumetric changes, using three-dimensional (3D) stereophotogrammetry after microimplant-assisted rapid palatal expansion (MARPE) in adult patients. Methods: Facial data were scanned using a white light scanner before and after MARPE in 30 patients. In total, 7 mm of expansion was achieved over a 4-week expansion period. We determined 10 soft tissue landmarks using reverse engineering software and measured 3D vector changes at those points. In addition, we calculated the distances between points to determine changes in the width of the nasal soft tissues. The volumetric change in the nose was also measured. Results: All landmarks except pronasale and subnasale showed statistically significant movement on the x-axis. Pronasale, subnasale, alar right, and alar left showed significant movement on the y-axis, while all landmarks except subnasale showed significant movement on the z-axis. The alar base width, alar width, and alar curvature width increased by 1.214, 0.932, and 0.987 mm, respectively. The average volumetric change was 993.33 ㎣, and the amount of increase relative to the average initial volume was 2.96%. Conclusions: The majority of soft tissue landmarks around the nasal region show significant positional changes after MARPE in adults. The nose tends to widen and move forward and downward. The post-treatment nasal volume may also exhibit a significant increase relative to the initial volume. Clinicians should thoroughly explain the anticipated changes to patients before MARPE initiation.