• The Journal of Korean Academy of Prosthodontics
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• v.45 no.4
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• pp.522-533
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• 2007

Statement of problem: Despite of the recent development of the titanium casting system methods, the casting defects such as imperfect casting and internal porosity were frequently observed. Purpose: The purposes of this study were to compare and measure the castability, microhardness, and surface reaction between Grade 2 pure titanium and Ti-6Al-4V by casting these alloys from the different sprue design conditions. Material and methods: Depending on the sprue designs and titanium alloys, 42 ready-made wax patterns were used. By analyzing the remodeling of the cast, internal porosity, microhardness, and titanium surface layer of SEM, there were several results we observed. Results: 1. The measured castability of titanium were categorized in the ascending order: individual sprue group, runner bar group, and single group. This data are based on the statistically signigicant differences. 2. The castability of titanium has not showed the statistically significant differences among the alloys. However, CP-Ti groups were superior to Ti-6Al-4V groups by showing the noticeable castability. 3. The surface layers of the castings of all groups have showed $5{\mu}m$ titanium oxide layers irrespective of sprue designs and titanium alloys. Conclusion: From the above study results, by fabricating the restorations from the centrifugal casting machine direct sprue designs revealed better castability. As we increased the number of sprues in the wax pattern, it revealed better castability. The castability of pure titanium rather than that of Ti-6Al-4V was remarkable. To fabricate the complex forms of the restorations, further researches on the efficient sprue designs and titanium alloys must be made.

• Archives of Craniofacial Surgery
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• v.21 no.4
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• pp.237-243
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• 2020

Background: The scalp is an important functional and aesthetic structure that protects the cranial bone. Due to its inelastic characteristics, soft-tissue defects of the scalp make reconstruction surgery difficult. This study aims to provide an improved scalp reconstruction decision making algorithm for surgeons. Methods: This study examined patients who underwent scalp reconstruction within the last 10 years. The study evaluated several factors that surgeons use to select a given reconstruction method such as etiology, defect location, size, depth, and complications. An algorithmic approach was then suggested based on an analysis of these factors. Results: Ninety-four patients were selected in total and 98 cases, including revision surgery, were performed for scalp reconstruction. Scalp reconstruction was performed by primary closure (36.73%), skin graft (27.55%), local flap (17.34%), pedicled regional flap (15.30%), and free flap (3.06%). The ratio of primary closure to more complex procedure on loose scalps (51.11%) was significantly higher than on tight scalps (24.52%) (p=0.011). The choice of scalp reconstruction method was affected significantly by the defect size (R=0.479, p<0.001) and depth (p<0.001). There were five major complications which were three cases of flap necrosis and two cases of skin necrosis. Hematoma was the most common of the 29 minor complications reported, followed by skin necrosis. Conclusion: There are multiple factors affecting the choice of scalp reconstruction method. We suggest an algorithm based on 10 years of experience that will help surgeons establish successful surgical management for their patients.

• Korean Journal of Construction Engineering and Management
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• v.11 no.2
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• pp.25-34
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• 2010

The building construction projects include a variety of risk factors due to uncertainties. To succeed in the projects, it is important how risks are managed. Risk management is composed of identification, analysis and response. Especially, the risk analysis is important to objectively calculate significance of risk factors. This paper evaluates a method to find priorities of risks using the AHP(Analytic Hierarchy Process). The method has some defects; (1) the consistency becomes weak as the number of pair-wise compared risks is large, and (2) the input and output procedures are complex when risks are added to or removed from a risk database. Thus the paper adopts the PROMETHEE(Preference Ranking Organization METHod Enrichment Evaluations) analysis process which is able to overcome the limitation of the AHP restricted to 9 risk factors. The PROMETHEE makes the procedure of risk analysis simple, when the risk factors pull out and put in the risk database. The purpose of this study is to provide process of risk analysis to use the PROMETHEE.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.8
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• pp.1358-1364
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• 2002

Presently, Multimedia data are increasing suddenly in broadcasting and internet fields. For retrieval of still images in multimedia database, content-based image retrieval system is implemented in this paper that user can retrieve similar objects from image database after choosing a wanted query region of object. As to extract color features from query image, we transform color to HSV with proposed method that similarity is obtained it through histogram intersection with database images after making histogram. Also, query image is transformed to gray image and induced to wavelet transformation by which spatial gray distribution and texture features are extracted using banded autocorrelogram and GLCM before having similarity values. And final similarity values is determined by adding two similarity values. In that, weight value is applied to each similarity value. We make up for defects by taking color image features but also gray image features from query image. Elevations of recall and precision are verified in experiment results.

• The Journal of Information Technology
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• v.4 no.2
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• pp.129-136
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• 2001

Most of the acoustic microscopes have been constructed acoustic image by simply measuring the amplitude of the reflected signal from the specimen. This method fails to produce images of good quality because the change in amplitude is not sensitive enough to specimen with fine variation. In this paper, we have been constructed the acoustic microscope system which has been able to measure simultaneously the amplitude and phase of the reflected ultrasonic signal. And also we have been constructed the amplitude and phase images for the 500 won coin as a sample and the alumium spacimen with internal round defect, and compared and analyzed these images. In expermental result, the phase image have shown better sensitive than the amplitude image and given better contrast for the micro height variation of specimen. It will be expected that the phase image can be used as an additional bit of information to improve ambiguituities in amplitude image on nondestructive testing for specimen with fine variation.

• Proceedings of the Korea Contents Association Conference
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• 2010.05a
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• pp.37-39
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• 2010

China's online games have been developed a decade, the online game development is very fast. The last monitoring from "gameScan$^{TM}$" shows that there are 6 local manufacturing MMORPG games in the top 20 in march 2010 of china.Through research top 4 MMORPG games, their graphic content is too similar. All of them are the subject of Chinese Martial-Arts and Chinese Mythology, the graphic design elements all from China's traditional culture. This phenomenon will be two defects, the first if the design follow the trend, it can reduce the risk of failure, but it'll lack of competitiveness also. The second is it can meet the needs of Chinese culture for the game players in china, but the complex Chinese mythology and the culture of Martial-Arts are not easy to be accepted for foreigners. There are many European and American games failed in China, because of the differences cultural, the Game players can't understand the history, religion and culture. so, we can get some experience from the successful game cases of Korea and Japan. Use of common cultural elements combined with some Chinese traditional culture to create a new fantasy world. And try some now contents about future or science fiction.

• Archives of Plastic Surgery
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• v.33 no.3
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• pp.359-366
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• 2006

Acquired facial deformities following cancrum oris sequelae manifested variably according to the nature of tissue necrosis. In cases that tissue loss extends over a wide area of the face, or the tissue nature is different due to congenital facial cleft, it is difficult to reconstruct with a single operation. As cancrum oris has virtually disappeared from our country, clinical report of reconstruction is also rare. We report 5 cases of facial deformities following cancrum oris sequelae. Since 1988, five adult patients(4 female and 1 male) were treated by authors. These patients, with an age ranged from 47 to 58 years, all suffered from acquired facial cleft such as facial mutilation, asymmetry. The stages of operation were from 1 to maximum of 5 operations. All surgeries achieved satisfactory results after a long-term follow-up. But one surgery in the case of palatal mucosal flap for the coverage of reconstructed maxilla alveolar bone resulted tissue sloughness, followed by osteomyelitis. Those were debrided and discarded. In conclusion, all sites of deformities were positioned around one of the oral commissures. In their past medical history, they have been suffering from measles, typhoid fever and unknown febrile illness. We diagnosed the acquired facial deformity following cancrum oris sequelae. The reconstruction of acquired facial deformity following cancrum oris sequelae were difficult due to extensive multiple tissue defects. Therefore multiple staged operations were inevitable. The authors reconstructed 5 cases of simple and complex form of facial deformity with minimum staged operations. All patients were satisfied functionally and cosmetically.

• Archives of Plastic Surgery
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• v.40 no.6
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• pp.721-727
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• 2013

Background One of the main concerns in orbital blowout fracture repair is a narrow operation field, due mainly to the innate complex three dimensions of the orbit; however, a deep location and extensive area of the fracture and soft tissue edema can also cause concern. Swelling of the orbital contents progresses as the operation continues. Mannitol has been used empirically in glaucoma, cerebral hemorrhage, and orbital compartment syndrome for decompression. The authors adopted mannitol for the control of intraorbital edema and pressure in orbital blowout fracture repair. Methods This prospective study included 108 consecutive patients who were treated for a pure blowout fracture from January 2007 to October 2012. For group I, mannitol was administered during the operation. Under general anesthesia, all patients underwent surgery by open reduction and insertion of an absorbable mesh implant. The authors compared postoperative complications, the reoperation rate, operation time, and surgical field improvement between the two groups. Results In patients who received intraoperative administration of mannitol, the reoperation rate and operation time were decreased; however, the difference was not statistically significant. The total postoperative complication rates did not differ. Panel assessment for the intraoperative surgical field video recordings showed significantly improved vision in group I. Conclusions For six years, mannitol proved itself an effective, reliable, and safe adjunctive drug in the repair of orbital blowout fractures. With its rapid onset and short duration of action, mannitol could be one of the best methods for obtaining a wider surgical field in blowout fracture defects.

• BMB Reports
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• v.50 no.6
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• pp.308-317
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• 2017

Bone morphogenetic protein type 2 receptor (BMPR2) is one of the transforming growth $factor-{\beta}$ ($TGF-{\beta}$) superfamily receptors, performing diverse roles during embryonic development, vasculogenesis, and osteogenesis. Human BMPR2 consists of 1,038 amino acids, and contains functionally conserved extracellular, transmembrane, kinase, and C-terminal cytoplasmic domains. Bone morphogenetic proteins (BMPs) engage the tetrameric complex, composed of BMPR2 and its corresponding type 1 receptors, which initiates SMAD proteins-mediated signal transduction leading to the expression of target genes implicated in the development or differentiation of the embryo, organs and bones. In particular, genetic alterations of BMPR2 gene are associated with several clinical disorders, including representative pulmonary arterial hypertension, cancers, and metabolic diseases, thus demonstrating the physiological importance of BMPR2. In this mini review, we summarize recent findings regarding the molecular basis of BMPR2 functions in BMP signaling, and the versatile roles of BMPR2. In addition, various aspects of experimentally validated pathogenic mutations of BMPR2 and the linked human diseases will also be discussed, which are important in clinical settings for diagnostics and treatment.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5213-5217
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• 2013

Transporter associated with antigen presenting (TAP) 1 and TAP2 genes are localized in the major histocompatability complex (MHC) class II region and form a heterodimer playing a key role in endogenous pathways for antigen presentation. Defects of these genes have been reported to be common in different types of cancer. Polymorphisms identified in these loci have also been investigated and reported to be associated with several autoimmune disorders, viral infections and neoplasms. In the present study, for the first time, the allele and genotype frequencies of TAP1-333, TAP2-565, TAP2-651 and TAP2-665 were determined in patients with hematological malignancies (HM) using a PCR-RFLP method and compared with the frequencies in the control group. Our results suggested an association of TAP1-333 polymorphism with multiple myeloma-MM and TAP2-565 polymorphism with chronic lymphoid leukemia-CLL. In addition, it could be concluded that the TAP2-665 GG genotype might be a risk factor for all types of hematological malignancies included in this study.