• Journal of the Korean Geotechnical Society
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• v.25 no.12
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• pp.13-25
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• 2009

In this paper, a numerical procedure of probabilistic slope stability analysis that considers the spatial variability of soil properties is presented. The procedure extends the deterministic analysis based on the limit equilibrium method of slices to a probabilistic approach that accounts for the uncertainties and spatial variation of the soil parameters. Making no a priori assumptions about the critical failure surface like the Random Finite Element Method (RFEM), the approach saves the amount of solution time required to perform the analysis. Two-dimensional random fields are generated based on a Karhunen-Lo$\grave{e}$ve expansion in a fashion consistent with a specified marginal distribution function and an autocorrelation function. A Monte Carlo simulation is then used to determine the statistical response based on the random fields. A series of analyses were performed to verify the application potential of the proposed method and to study the effects of uncertainty caused by the spatial heterogeneity on the stability of slope. The results show that the proposed method can efficiently consider the various failure mechanisms caused by the spatial variability of soil property in the probabilistic slope stability assessment.

• Restorative Dentistry and Endodontics
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• v.46 no.4
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• pp.59.1-59.14
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• 2021

Objectives: This study compared the Biodentine, MTA Repair HP, and Bio-C Repair bioceramics in terms of bond strength to dentin, failure mode, and compression. Materials and Methods: Fifty-four slices obtained from the cervical third of 18 single-rooted human mandibular premolars were randomly distributed (n = 18). After insertion of the bioceramic materials, the push-out test was performed. The failure mode was analyzed using stereomicroscopy. Another set of cylindrically-shaped bioceramic samples (n = 10) was prepared for compressive strength testing. The normality of data distribution was analyzed using the Shapiro-Wilk test. The Kruskal-Wallis and Friedman tests were used for the push-out test data, while compressive strength was analyzed with analysis of variance and the Tukey test, considering a significance level of 0.05. Results: Biodentine presented a higher median bond strength value (14.79 MPa) than MTA Repair HP (8.84 MPa) and Bio-C Repair (3.48 MPa), with a significant difference only between Biodentine and Bio-C Repair. In the Biodentine group, the most frequent failure mode was mixed (61%), while in the MTA Repair HP and Bio-C Repair groups, it was adhesive (94% and 72%, respectively). Biodentine showed greater resistance to compression (29.59 ± 8.47 MPa) than MTA Repair HP (18.68 ± 7.40 MPa) and Bio-C Repair (19.96 ± 3.96 MPa) (p < 0.05). Conclusions: Biodentine showed greater compressive strength than MTA Repair HP and Bio-C Repair, and greater bond strength than Bio-C Repair. The most frequent failure mode of Biodentine was mixed, while that of MTA Repair HP and Bio-C Repair was adhesive.

• Restorative Dentistry and Endodontics
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• v.46 no.2
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• pp.22.1-22.12
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• 2021

Objectives: This study evaluated and compared the effects of radiation therapy on the dislocation resistance of AH Plus and BioRoot RCS applied to dentin and the sealer-dentin interface. Materials and Methods: Thirty single-rooted teeth were randomly assigned to 2 groups (n = 15 each): AH Plus (Dentsply DeTrey) and BioRoot RCS (Septodont). Each group was subdivided into control and experimental groups. The experimental group was subjected to a total radiation dose of 60 Gy. The root canals of all samples were cleaned, shaped, and obturated using the single-cone technique. Dentin slices (1 mm) were sectioned from each root third for the push-out test and scanning electron microscopy (SEM) was done to examine the sealer-dentin interface. The failure mode was determined using stereomicroscopy. Bond strength data were analyzed by the independent t-test, 1-way analysis of variance, and the Tukey post hoc test (α = 0.05). Results: Significantly lower bond strength was observed in irradiated teeth than non-irradiated teeth in the AH Plus group (p < 0.05). The BioRoot RCS group showed no significant reduction in bond strength after irradiation (p > 0.05) and showed a higher post-irradiation bond strength (209.92 ± 172.26 MPa) than the AH Plus group. SEM revealed slightly larger gap-containing regions in irradiated specimens from both groups. Conclusions: The dislocation resistance of BioRoot RCS was not significantly changed by irradiation and was higher than that of AH Plus. BioRoot RCS may be the sealer of choice for root canal treatment in patients undergoing radiation therapy.

• Journal of the Korean Society of Food Culture
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• v.24 no.4
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• pp.366-375
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• 2009

This study examined the changes of side dishes in "Eumsikdimibang", "Gyuhapchongseo", "Chosunmusangsinsikyorijebub" over time. As food ingredients, seaweed, red pepper, salted fish, Korean hot pepper paste have been used in "Gyuhapchongseo". The use of cattle by parts, saltwater fish, Chinese cabbage, powdered red pepper, garlic have increased in"Chosunmusangsinsikyorijebub". Cooking techniques, such as the use of wheat flour, a double boiler by the use of steam, and boiling and then roasting cuisine were mostly used in"Eumsikdimibang", but reduced in"Gyuhapchongseo". In "Gyuhapchongseo", the cooking methods are primarily aimed at a positive visual effect, and slices of dried meat seasoned with spices have increased. In"Chosunmusangsinsikyorijebub", various Tang (Guk), the taste of food changed by controlling the gravy content (Gigimi, Chigye, Chorim), meat mixing oil, vegetable and mushroom together to cook and boiling down the main food ingredients to soak the seasoning were increased. Dog-meat steamed dish using the intestine of dog in "Eumsikdimibang" was changed to small intestine of cattle steamed dish in "Gyuhapchongseo". And seasoned dog meat with choncho in "Eumsikdimibang" influenced on beef tail soup with Korean hot pepper paste in "Gyuhapchongseo", and Yookgyejang soup using Korean hot pepper paste in"Chosunmusangsinsikyorijebub". In steamed young chicken, the stuffing such as soybean paste, choncho, welsh onion, leek and flour in "Eumsikdimibang" was changed to minced beef, welsh onion, dropwort and Shiitake mushroom in"Gyuhapchongseo". The steamed young chicken in "Chosunmusangsinsikyorijebub" with stuffing was added to chicken soup using glutinous rice, and ginseng powder. Now, the chicken soup was changed to Samgyetang with glutinous rice, and ginseng. In "Chosunmusangsinsikyorijebub", various vegetable dishes were cooked with beef.

• Journal of the Korean Society of Food Culture
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• v.25 no.4
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• pp.428-455
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• 2010

Radish kimchi is a typical side-dish in Korean traditional food and is a way of keeping vegetables for a extended period using fermentation. This study examined the classification, usage, eating history, variety, and recipes of Korean radish kimchi through ancient and modern era literature. The Korean radish kimchi were categorized into six groups: kkakttugi, seokbakji (or nabakkimchi), dongchimi, jjanji, jangachi, and jangkwa. According to the record, the eating history of radish kimchi comes from before the age of the Three Kingdom period. Radish was preserved in salt, vinegar, soybean paste or lees of fermented liquor in the early times. This pickled radish was not supposed to be watery. Radish kimchi was divided into watery kimchi (dongchimi) during the period of United Silla and the Koryo Dynasty. Kimchi was mixed with Chinese cabbage to make seokbakji or nabakkimchi. Up to the early Chosun Dynasty, the key ingredient of kimchi was radish. After the middle of the Chosun Dynasty, kimchi was mixed with red pepper powder, salted fish, soybean sauce, and various ingredients. There were many kinds of radish kimchi during the late Chosun Dynasty. In the 11 Korean recipe books published within the past 100 years, there are nine kinds of kkakttugi, three kinds of seokbakji, four kinds of dongchimi, three kinds of jjanji, nine kinds of jangachi, and five kinds of jangkwa. Kkakttugi (cubed, sliced or julienne radish) was pickled with salt, red pepper powder, garlic, green onion, oyster, sugar, salted fish, and more. Seokbakji and nabakkimchi were not as salty, so they could not be preserved as long. Dongchimi (watery radish kimchi without red pepper powder) was made of radish, water, salt, 18 side ingredients, 13 condiments, and seven garnishes. Jjanji was pickled to be very salty and was eaten during summer. Jangachi can be used as a regular side dish and is made of radish or dried radish slices pickled or seasoned with salt, soy sauce, vinegar, soybean paste, lees of fermented liquor, and spices. Jangkwa is used as a stir-fry method and has been segregated from jangachi relatively recently.

• Journal of the Korean Society of Food Culture
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• v.22 no.2
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• pp.225-234
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• 2007

This study was performed to investigate the preference and perception on fruits especially, focusing on apples and pears served in elementary school lunch programs. The subjects of this study were 1,106 students (504 female and 595 male students)from seven elementary schools in Seoul. The survey was conducted by using self-administered questionnaire from July 10 to July 20, 2006. Based on the frequency analysis results, 45% of respondents ate fruits every day and 42% had fruits 2-3 times per week. Approximately, 53% of respondents indicated their usual time to eat fruits was after dinner and secondly 27% had fruits between lunch and dinner. Majority of respondents chose a watermelon as the most preferred fruits and the first chosen among nine fruits (apple, pear, madarin, strawberry, cherry tomato, watermelon, grape, melon, and peach). Cherry tomato was found as the least preferred fruits by 30% of students, however cherry tomato was most frequently offered fruits in elementary school lunch menu. About 50% students were satisfied with the served fruits in their school lunch program. In addition, most students said that they would have fruits more frequently in their lunch menu. However, one fifth of students addressed that they were not satisfied with the fruits in school lunch program because of kinds of fruits, freshness of fruits, taste of fruits, and quantity of fruits. Almost 71% of students preferred apples. Seventy three percents of students preferred eating apples without peel and 78% of students ate apples as slices of apples. In addition, 61% of students indicated their preference of apple salads. Many students responded they did not eat apples and pears frequently since they do not have a chance to eat them. The implications to increase the chance to eat fruits and promote elementary children's fruits consumption were discussed.

• Restorative Dentistry and Endodontics
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• v.48 no.3
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• pp.28.1-28.13
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• 2023

Objectives: This study aimed to investigate the effect of the application method of 2% chlorhexidine (CHX) and its influence on the adhesion of fiberglass posts cemented with a self-adhesive resin cement. Materials and Methods: Sixty human mandibular premolars were endodontically treated and divided into 5 groups (n = 12), according to the canal irrigant and its application method: 2 groups with conventional syringe irrigation (CSI)-2.5% sodium hypochlorite (NaOCl) (control) and 2% CHX- and 3 groups with 2% CHX irrigation/activation-by passive ultrasonic irrigation (PUI), Easy Clean file, and XP-Endo Finisher file. Two roots per group were evaluated for smear layer (SL) removal by scanning electron microscopy. For other roots, fiber posts were luted using a self-adhesive resin cement. The roots were sectioned into 6 slices for push-out bond strength (BS) (7/group) and nanoleakage (NL) (3/group). Data from SL removal were submitted to Kruskal-Wallis and Student-Newman-Keuls tests (α = 0.05). Data from BS and NL were evaluated by 2-way analysis of variance and Tukey's test (α = 0.05). Results: For SL removal and BS, the CHX irrigation/activation promoted better values than CSI with CHX (p < 0.05), but it was not significantly different from CSI with NaOCl (p > 0.05). For NL, the lowest values were obtained by the chlorhexidine irrigation/activation groups (p < 0.05). Conclusions: Active 2% CHX irrigation can be used to improve the post space cleaning and adhesion before fiber post cementation with self-adhesive resin cements.

• Journal of the Korean Society of Radiology
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• v.18 no.1
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• pp.21-26
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• 2024

The one of the famous deep learning models for object detection task is you only look once version 5 (YOLOv5) framework based on the one stage architecture. In addition, YOLOv5 model indicated high performance for accurate lesion detection using the bottleneck CSP layer and skip connection function. The purpose of this study was to evaluate the performance of YOLOv5 framework according to various hyperparameters in position emission tomogrpahy (PET) phantom images. The dataset was obtained from QIN PET segmentation challenge in 500 slices. We set the bounding box to generate ground truth dataset using labelImg software. The hyperparameters for network train were applied by changing optimization function (SDG, Adam, and AdamW), activation function (SiLU, LeakyRelu, Mish, and Hardwish), and YOLOv5 model size (nano, small, large, and xlarge). The intersection over union (IOU) method was used for performance evaluation. As a results, the condition of outstanding performance is to apply AdamW, Hardwish, and nano size for optimization function, activation function and model version, respectively. In conclusion, we confirmed the usefulness of YOLOv5 network for object detection performance in nuclear medicine images.

• Journal of Periodontal and Implant Science
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• v.53 no.6
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• pp.453-466
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• 2023

Purpose: This study aimed to quantify alveolar bone morphology, demonstrate the relationship between tooth angulation and alveolar bone thickness, and introduce a new classification for anterior mandibular teeth related to immediate implant placement (IIP). Methods: Cone-beam computed tomography (CBCT) images of 211 anterior mandibular teeth were analyzed in sagittal slices to measure the thickness of the facial alveolar bone crest (FAB1) and apex (FAB2), and the lingual alveolar bone crest (LAB1) and apex (LAB2). Tooth angulation was classified as 1°-10°, 11°-20°, and >20° according to the tooth's long axis and alveolar bone wall. Spearman correlation coefficients were used to evaluate correlations between the variables. Results: FAB1 and LAB1 were predominantly thin (<1 mm) (84.4% and 73.4%, respectively), with the lateral incisors being thinnest. At the apical level, FAB2 and LAB2 were thick in 99.5% and 99.1% of cases, respectively. Significant differences were documented in FAB2 (P=0.004), LAB1 (P=0.001), and LAB2 (P=0.001) of all mandibular teeth. At all apical levels of the inspected teeth, a significant negative correlation existed between TA and FAB2. Meanwhile, TA showed a significant positive correlation with LAB2 of the lateral incisors and canines. These patterns were then divided into class I (thick facial and lingual alveolar bone), class II (facially inclined teeth) with subtype A (1°-10°) and subtype B (11°-20°), and class III (lingually inclined teeth) with subtype A (1°-10°) and subtype B (11°-20°). Conclusions: Mandibular anterior teeth have predominantly thin facial and lingual crests, making the lingual bone apical thickness crucial for IIP. Although anchorage can be obtained from lingual bone, tooth angulation and tooth types had an impact on IIP planning. Hence, the new classification based on TA and alveolar bone wall may enable rational clinical planning for IIP treatment.

• Hip & pelvis
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• v.34 no.1
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• pp.18-24
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• 2022

Purpose: The aim of this study was to determine whether there is a correlation between the type and stability of intertrochanteric fractures caused by low-energy trauma and gluteus muscle volume. Materials and Methods: A total of 205 elderly (>65 years) patients with intertrochanteric fractures caused by low-energy trauma treated from January 2018 to December 2020 were included in this study. The mean age of patients was 81.24 years (range, 65-100 years). Fractures were classified according to the Jensen modification of the Evans classification. The cross-sectional area of the contralateral gluteus muscle (minimus, medius, and maximus) was measured in preoperative axial computed tomography slices. An analysis and comparison of age, body mass index (BMI), weight, height, and the gluteus muscle area in each fracture type group was performed. Results: In the uni-variable analysis, statistically significant taller height was observed in patients in the stable intertrochanteric fracture (modified Evans 1 and 2) group compared with those in the unstable intertrochanteric fracture (modified Evans 3, 4, and 5) group (P<0.05). In addition, significantly higher BMI-adjusted gluteus muscle area (gluteus muscle area/BMI) was observed for the stable intertrochanteric fracture group compared with the unstable intertrochanteric fracture group except for the BMI-adjusted gluteus minimus area (P=0.112). In multivariable analysis, only the BMI-adjusted gluteus maximus (P=0.042) and total gluteus areas (P=0.035) were significantly higher in the stable group. Conclusion: Gluteal muscularity around the hip, especially the gluteus maximus, had a significant effect on the stability of intertrochanteric fractures.