• The korean journal of orthodontics
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• v.47 no.3
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• pp.207-212
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• 2017

The popularity of clear overlay retainers (CORs) has increased recently because of their advantages such as better esthetics, cost effectiveness, easy fabrication, and good compliance. However, a deficiency in posterior occlusal settling is a reported limitation of CORs. The aim of this study was to evaluate the posterior occlusal contact changes in a new type of clear orthodontic retainer called Oral-treaper (OTP), which consists of three layers and has stronger mechanical characteristics than do conventional retainers. Three patients who completed fixed orthodontic treatment received OTP as a removable retainer. Cast models were fabricated after the removal of fixed appliances (T1) and after 4 to 11 months of using the retainers (T2). We evaluated all the cast models to compare the post-orthodontic settling pattern during the use of the OTPs. The depth of occlusal contacts was evaluated using color maps. The OTP did not prevent vertical settling in all patients but resulted in an improvement in posterior occlusal contact points.

• Genomics & Informatics
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• v.8 no.2
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• pp.81-85
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• 2010

The aim of the study was to investigate pig reference families, generated from Korean native pigs (KNP) that were crossed with Yorkshire (YS) breeds, which were used to evaluate genetic markers to select breeding animals with superior pork quality. A set of five candidate genes (PRKAG3, MC4R, CAST, ESR, and PRLR ) was analyzed for association with pork quality traits. PRKAG3 (I199V) SNP genotypes were significantly associated with muscle moisture, protein, and fat contents. The MC4R D298N polymorphism was significantly associated with meat tenderness and color traits. The CAST polymorphism was significantly associated with muscle moisture and crude protein traits. These three genes have been associated with pork quality traits in other pig populations, and some of our results are consistent with earlier studies. In addition, two reproductive candidate genes (ESR and PRLR ) did not have significant associations. These results suggest that further study is warranted to investigate and develop more DNA markers associated with pork quality in our KNP-crossed pig families.

• The Journal of Advanced Prosthodontics
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• v.15 no.3
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• pp.145-154
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• 2023

PURPOSE. The objective of this study was to investigate how internal structures influence the overall and marginal accuracy of full arch preparations fabricated through additive manufacturing in different printing systems. MATERIALS AND METHODS. A full-arch preparation digital model was set up with three internal designs, including solid, hollow, and grid. These were printed using three different resin printers with nine models in each group. After scanning, each data was imported into the 3D data processing software together with the master cast, aligned and trimmed, and then put into the 3D data analysis software again to compare the overall and marginal deviation whose results are expressed using root mean square values and color maps. To evaluate the trueness of the resin model, the test data and reference data were compared, and the precision was evaluated by comparing the test data sets. Color maps were observed for qualitative analysis. Data were statistically analyzed by one-way analysis of variance and Bonferroni method was used for post hoc comparison (α = .05). RESULTS. The influence of different internal structures on the accuracy of 3D printed resin models varied significantly (P < .05). Solid and grid models showed better accuracy, while the hollow model exhibited poor accuracy. The color maps show that the resin models have a tendency to shrink inwards. CONCLUSION. The internal structure design influences the accuracy of the 3D printing model, and the effect varies in different printing systems. Irrespective of the kind of printing system, the printing accuracy of hollow model was observed to be worse than those of solid and grid models.

• The Journal of Korean Academy of Prosthodontics
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• v.40 no.3
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• pp.287-295
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• 2002

Statement of Problem. Endodontically treated teeth frequently required posts and cores to provide retention and resistance form for crowns. In spite of excellent mechanical properties of metal post and core, its metallic color can be detected through all ceramic restorations occasionally. To solve esthetic problems of metal post and core zirconia post system has been introduced recently. Purpose. The purpose of this study was to examine the fracture strength and mode of resin root analogs restored with zirconia, gold and titanium posts with resin, ceramic and metal cores after cementation with metal crowns. Materials and methods. To avoid the morphological variations of natural teeth, 40 root analogs were fabricated with composite resin. Forty resin root analogs were randomly assigned to four groups according to post and core materials: Group A: cast gold post and core and complete cast crowns, as control. Group B: titanium posts (Parapost, Coltent/Whaledent Inc., NJ, USA) and composite resin cores. Group C: zirconia posts (Cosmopost, Ivoclar AG, Schaan/Liechtenstein) and composite resin cores Group D: zirconia posts and heat-pressed ceramic cores (IPS Empress Cosmo Ingots, Ivoclar AG) After thermocycling ($5^{\circ}C{\sim}55^{\circ}C$, 30 sec.), cyclic loading was applied at 3mm below the incisal edge on the palatal surfaces at an angle of 135 degree to the long axis (2Hz, 50N, 50000cycles). Fracture strength was measured by universal testing machine (Instron, High Wycombe, UK) and fracture pattern of restored resin root analogs was also evaluated. Results and conclusion. Within the limitations of this study following results were drawn. 1. Resin root analogs restored with zirconia posts and composite resins demonstrated lowest fracture strength among tested groups. 2. There was no significant difference in the fracture strength between zirconia posts and heat pressed glass ceramic cores and cast gold posts and cores 3. The fracture strength of resin root analogs restored with titanium posts and composite resin cores was lower than that of gold posts and cores. 4. The deep oblique fracture lines were dominantly observed in root analogs restored with cast gold post and core and zirconia post and heat-pressed ceramic core groups.

• Journal of the Korea Computer Graphics Society
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• v.2 no.1
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• pp.1-6
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• 1996

In ray tracing of 3D volume data, the color of each pixel in the image is typically obtained by accumulating the contributions of sample points on the ray cast from the pixel point. This accumulation is most naturally represented by integration. In most methods, however, it is done by numerical summation because analytical solution to the integration are hard to find. This paper shows that a semi-analytical solution can be obtained for a typical ray tracing of volume data. Tentative conclusions about the significance and usefulness of our approach are presented based on our experiments.

• Journal of the Korean Society of Costume
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• v.58 no.10
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• pp.123-134
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• 2008

The purpose of this study is to examine the postmodern characteristics in global fashion advertising. This analysis of postmodern print campaign strategies will increase the understanding of global fashion consumer and assist in establishing global advertising strategies for domestic fashion brands. 2006 A/W and 2007 S/S magazine campaigns for 190 fashion luxury brands were are collected, which were uploaded on the WGSN website. All advertising campaigns were analyzed in terms of postmodern features by four fashion professionals. As a result, major findings are as follows; First, advertising model stereotype was deconstructed. Besides young celebrities, ad models such as real people and old or childish celebrities were cast. Second, expression technique was deconstructed. Chromatic harmony was broadened to include black and white advertising, additive and subtractive color mixing. Innovative layout techniques such as collage were used. And also narrative structure was deconstructed. Third, diverse issues such as environmental message, globalization, fantasy, feminism, everyday life were expressed as advertisement appeals.

• Journal of Environmental Science International
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• v.11 no.11
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• pp.1183-1187
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• 2002

Existing retaining walls are usually made from only one cast form and any damage must be promptly repaired. However, when a part of a retaining wall is repaired, a gap can be created between the repaired and existing parts, along with an unpleasing visual effect. As such, the whole structure is often reconstructed, rather than repairing one part, resulting in construction waste and possible contamination of the environment. Accordingly, the current study proposes a construction method for a retaining wall that uses separate blocks to downsize of quantity of construction waste. In addition, by changing the color or modifying the block cover a more environmentally friendly retaining wall construction method is achieved.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.35-40
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• 2003

Immense quantities of coal combustion by-products are produced every year, and only a small fraction of them are currently utilized. The purpose of this study is to investigate reused techniques of coal to highly economic growth and expansion of country base industry. So, in this study, artificial aggregate was developed to recycle coal ash by non-sintering technique and crush method. And characteristic of developed artificial aggregate was examined. Also, noise barriers using developed artificial aggregate was made by link of development of ECO-construction product and is preparing sound absorption and transmission loss experiment. Result of study was showed that artificial aggregate was more proper to use a noise barriers and this is expected to satisfy sound absorption standard in this study. So, if shape and color considering surround and design technology is studied continuously, it can be expected to make ECO-precast product as well as maximize waste recycling.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.533-536
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• 1997

In this paper, we visualized 3-dimensional volume of heart using volume method by thresholding in EBT slices data. Volume rendering is the method that acquire the color by casting a pixel ray to volume data. The gray level of heart region is so high that we decide heart region by thresholding method. When a pixel ray is cast to volume data, the region that is higher than threshold value becomes heart region. We effectively rendered the heart volume and showed the 3-dimensional heart volume.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.423-428
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• 1999

Potato starches were hydroxypropylated with 2.5, 5.0, 7.5, and 10.0% propylene oxide(PO) to improve mechanical properties of starch polyethylene film. Starch polyethylene cast films were prepared that contained 5% or 10% of the hydroxypropylated potato starch. Mechanical properties of these films were measured and compared to those of the films containing native potato starch. DS(degree of substitution) increased proportionally as propylene oxide concentration increased. Relative crystallinity in X ray diffraction patterns was decreased and starch granule observed by scanning electron micro scopy was destroyed by severe hydroxypropylation. In color properties of films, b value was not significantly different in the films but 5% starch polyethylene films with 2.5 PO starch showed the lowest L and a value. Tensile strength and strain energy of the films except the film containing 10.0 PO starch were higher than those of the containing native starch.