• Journal of Electrical Engineering and Technology
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• v.7 no.5
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• pp.765-771
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• 2012

$SF_6$ gas has been used as arc quenching and insulating medium for high and extra high voltage switching devices due to its high dielectric strength, its excellent arc-quenching capabilities, its high chemical stability and non toxicity. Despite of its significant contributions, the gas was classified as one of the greenhouse gas in the Kyoto Protocol. Thus, many researches are conducted to find out the replacement materials and to develop the $SF_6$ gas useless electrical equipment. This paper describes experiments on the temperature change-related breakdown characteristics of $SF_6$ gas ($SF_6$) and $SF_6$ liquid ($LSF_6$) in a model GIS(Gas-Insulated Switchgear) chamber in order to show the possibility of more stable and safe usages of $SF_6$ gas. The breakdown characteristics are classified into three stages, namely the gas stage of $SF_6$ according to Paschen's law, the coexisting stage of $SF_6$ gas with liquid in considerable deviation at lower temperature, and the stage of $LSF_6$ and remaining air. The result shows that the ability of the $LSF_6$ insulation is higher than the high-pressurized $SF_6$. Moreover, it reveals that the breakdown characteristics of $LSF_6$ are produced by bubble-formed $LSF_6$ evaporation and bubbles caused by high electric emission and the corona. In addition, the property of dielectric breakdown of $LSF_6$ is determined by electrode form, electrode arrangement, bubble formation and movement, arc extinguishing capacity of the media, difficulty in corona formation, and the distance between electrodes. The bubble formation and flow separation phenomena were identified for $LSF_6$. It provides fundamental data not only for $SF_6$ gas useless equipment but also for electric insulation design of high-temperature superconductor and cryogenic equipment machinery, which will be developed in future studies.

• Journal of radiological science and technology
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• v.2 no.1
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• pp.71-83
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• 1979

Not only the insulating oil used for extra high voltage and high capacity transformer has a lot of possibilites of a corona discharge in oil, but the oil is easily degraded by a response of light oxidization. This study is either to classfy, with priority given to a transformer oil produced in Korea belonging to, the insulating oil No. 2, the sample irradiated the ultraviolet rays, treated a corona discharge in oil by a high voltage DC source and done nothing, or to measure the characteristics of breakdown, V-i, I-t and electrode material. The obtained results can be summarized as followings: (1) Unless the sample is contacted with the air, on the process to irradiate the ultraviolet rays, the sample less influence on the changes of the electric characteristics. At the same time, if the sample is contacted with the air and irradiated the ultraviolet rays, the sample shows a remarkable changes of the electric characteristics, and a declined breakdown strength. This tells us that the influence of the light irradiation must be considered as a primary factor of degrading the insulating oil. (2) In the oil treated by a corona discharge, breakdown voltage is declined more than in the oil not to be treated with it. This means that the degradation of the insulating oil is getting increased by a corona discharge in oil. (3) It shows that the increase of conducting current has little to do with breakdown voltage. (4) The conducting current depending on the electrode materials can be put in order by value as Al>Cu>Fe. This is due to the differences of the work function of each metals, and an chemical reaction with the insulating oil. These result can be a great help in verifying the degradation progress of the insulating oil and furnish a new technical information to the manufacturers of the insulating oil and electrical equipment designers and operators. Besides, this study would be helpful to improve the electrical characteristics of the insulating oil produced in Korea.

• Korean Institute of Interior Design Journal
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• v.24 no.1
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• pp.43-53
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• 2015

As part of alternative of elderly problems in the future super-aging society, this study aims to extract an improvement plan of interior environment design of Seoul-type day care centers to expand in future by observing day care centers as medical and healing environments, from the perspective of user experience. For this study, after selecting major activity areas of representative cases of Seoul-type day care centers, user behaviors in the space were observed and 4 seniors of baby-boom generation who are potential uses were chosen as personas by reflecting characteristics of healthy elderly, physical aging, mental aging and infirm elderly, from the perspective of user experience. Based on previous studies on healing environments, these characteristics and demands of personas were classified into environmental aspects, physical aspects and mental aspects to extract an improvement plan. The study results are as follows. First, interior environment design reflecting persona characteristics helps the elderly adapt to the environment and provides a comfortable environment like home for stability, treatment and recovery of memory. Second, interior environment design reflecting persona characteristics helps psychological healing through light entering the large windows and natural environment elements. Third, for interior environment design reflecting persona characteristics, finish materials with bright and soft colors should be used to change the images of facilities positively. Fourth, spatial composition should be remedied through division of space and built-in furniture depending on the needs of users for loitering of extra time and programs.

• Journal of the Korean Society of Clothing and Textiles
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• v.39 no.6
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• pp.852-866
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• 2015

This study analyzes the form of sleeve heads, which is an important internal element that affects the appearance of jacket sleeves. It characterized sleeve head forms by investigating angles, materials, and a combination of formations for 50 sleeve heads. It conducted an appearance evaluation by comparing and analyzing the results. This paper develops a sleeve head appropriately for sleeve construction. The study results are as follows. First, the product was divided into three parts: based on, force receiving, and sleeve cap parts. There were four types of man's sleeve head: straight, arc, and curve A and B types. The woman's sleeve head had two types: straight and curve B type. Second, the feature of each type of sleeve head was analyzed. A straight type emphasized the based on part. An arc type highlighted the force receiving part while the based on part decreased. The sleeve cap part, force receiving part, and based on part were emphasized in the arc type sleeve head. Third, as a result of the appearance evaluation, each type was rank as straight type < arc type ${\leq}$ curve A < curve B. The straight type did not get positive results as it had extra ease when the sleeve head was attached to a Jacket Sleeve. The arc type was evaluated poorly due to an inappropriate sleeve cap composition. The curve type received an excellent overall outcome as it fit into the sleeve cap part well and highlighted the force receiving part in order to minimize front and back wrinkles. Therefore, the curve type made the resemblance of the jacket appearance perfect and closest to the sleeve pattern.

• Archives of design research
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• v.18 no.2 s.60
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• pp.255-264
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• 2005

The development of personal computers and the Internet led to changes of instructor-student and student-student relationships in design education. New resources of design education with proper materials and tools have to be offered for teaching and learning. The purpose of this research is to develop Basic Graphic Tools(BGTs) on screen that help students to practice the design principles, and to evaluate the BGTs' usability to enhance the credibility of extra tools for online design learning. The BGTs has to be developed to minimize the gap between the online and traditional classroom settings and to maximize the diverse advantage of lecture content driven from technology. Students were given certain design requirements to explore BGTs and a learning guide/performance test after the lecture to evaluate the tools. The test was performed under the e-learning program serviced by C college. This research has presented some encouraging results and raises questions toward future work: how do BGTs impact the feasibility of an online design lecture.

• Analytical Science and Technology
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• v.24 no.4
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• pp.282-289
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• 2011

Rapid screening method for the determination of the emissions of pollutants from vehicle interior parts and materials have been developed as ISO 12219-2 which is using bag and based on a static condition. The method was not controlled humidity in the test bag, so it is not suitable test method for formaldehyde emission test which is highly related to humidity condition. In this study, possibility of control humidity in the static test bag by adding extra water and the effect of humidity condition for formaldehyde emissions have been investigated. The relative humidity in the test bag was affected not only amount of water added also material of test bag and test specimen. The emission intensity of formaldehyde was increased according to increasing relative humidity in test bag. But excessively supplied water was condensed on the inner surface of test bag and surface of sample specimen that were sorption formaldehyde and were reduced its emission intensity.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.31-37
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• 2013

Background: Throughout Indonesia, thyroid cancer is one of the ten commonest malignancies, with papillary thyroid carcinoma (PTC) in our hospital accounting for about 60% of all thyroid nodules. Although fine needle aspiration biopsy (FNAB) is the most reliable diagnostic tool, some nodules are diagnosed as indeterminate and second surgery is common for PTC. The aim of this study was to establish the diagnostic value and feasibility of testing the BRAF T1799A mutation on FNA specimens for improving PTC diagnosis. Materials and Methods: This prospective study enrolled 95 patients with thyroid nodules and future surgery planned. Results of mutational status were compared with surgical pathology diagnosis. Results: Of the 70 cases included in the final analysis, 62.8% were PTC and the prevalence of BRAF mutation was 38.6%. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for BRAF mutation analysis were 36%, 100%, 100% and 48%, respectively. With other data findings, nodules with "onset less than 5 year" and "hard consistency" were proven as diagnostic determinants for BRAF mutation with a probability of 62.5%. This mutation was also a significant risk factor for extra-capsular extension. Conclusions: Molecular analysis of the BRAF T1799A mutation in FNAB specimens has high specificity and positive predictive value for PTC. It could be used in the selective patients with clinical characteristics to facilitate PTC diagnosis and for guidance regarding extent of thyroidectomy.

• The Journal of Advanced Prosthodontics
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• v.9 no.5
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• pp.381-386
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• 2017

PURPOSE. To integrate extra-oral facial scanning information with CAD/CAM complete dentures to immediately rehabilitate terminal dentition. MATERIALS AND METHODS. Ten patients with terminal dentition scheduled for total extraction and immediate denture placement were recruited for this study. The patients were submitted to a facial scanning procedure using the in-office PritiMirror scanner with bite registration records in-situ. Definitive stone cast models and bite records were subsequently submitted to a lab scanning procedure using the lab scanner (iSeries DWOS; Dental Wings). The scanned models were used to create a virtual teeth setup of a complete denture. Using the intra-oral bite records as a reference, the virtual setup was incorporated in the facial scan thereby facilitating a virtual clinical evaluation (teeth try-in) phase. After applying necessary adjustments, the virtual setup was submitted to a CAM procedure where a 5-axis industrial milling machine (M7 CNC; Darton AG General) was used to fabricate a full-milled PMMA immediate provisional prosthesis. RESULTS. Total extractions were performed, the dentures were immediately inserted, and subjective clinical fit was evaluated. The immediate provisional prostheses were inserted and clinical fit, occlusion/articulation, and esthetics were subjectively assessed; the results were deemed satisfactory. All provisional prostheses remained three months in function with no notable technical complications. CONCLUSION. Ten patients with terminal dentition were treated using a complete digital approach to fabricate complete dentures using CAD/CAM technology. The proposed technique has the potential to accelerate the rehabilitation procedure starting from immediate denture to final implant-supported prosthesis leading to more predictable functional and aesthetics outcomes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.41 no.5
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• pp.246-250
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• 2015

Objectives: This study investigated patients with oral and maxillofacial lacerations who visited the emergency room over a three-year period in an effort to determine the optimal treatment for these injuries. Materials and Methods: This study examined 1,742 patients with oral and maxillofacial lacerations with 2,014 different laceration locations who visited the emergency room of Pusan National University Hospital (Busan, Korea) over three years, from January 2011 to December 2013. Patients were classified by sex, age, visit day, cause of injury, injury site, and the presence or absence of soft tissue and tooth injuries. Results: The male to female ratio was 2.50:1. Patients under 10 years old were seen most frequently. Most emergency room visits were on weekends. Among intra-oral lacerations, the lip area was the most vulnerable site; among extra-oral lacerations, the chin area was most frequently injured. The most frequent etiology was a slip down. Most lacerations occurred without bone fracture or tooth damage. Conclusion: Laceration may differ in large part as compared with the fracture. Therefore, it is necessary to continue collecting data on oral and maxillofacial lacerations to establish optimal emergency room diagnosis and treatment strategies.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7271-7275
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• 2014

Background: The aim of the present study was to evaluate the presentation, clinical course and outcome between children and young adults with differentiated thyroid cancer (DTC) treated in our hospital. Materials and Methods: The medical records of 145 patients with DTC who underwent surgery followed by radioiodine and thyroid hormone (TSH) suppression were retrospectively reviewed. The follow up was between January 2006 and June 2012. These patients consisted of 38 children (age${\leq}18y$) and 107 young adult patients (age${\leq}30y$). The clinical characteristics and outcome were analyzed and compared, and the progression-free survival (PFS) was evaluated using the Kaplan-Meier method. Results: At initial diagnosis, a greater degree of extra thyroidal extension was found in children than adults patients (p<0.001). However, there was no significant difference between the two groups with regard to the tumor size and the presence of lymph node or distant metastasis (p=0.172, p=0.050 and p=0.068, respectively). The extent of surgery and the cumulative or mean dose of radioiodine were similar in both groups. During the follow up, the overall survival rate was 100% for both groups, and the PFS rate was similar in children and in young adults group (log rank test, ${\chi}^2$=0.126, p=0.723). Conclusions: In comparison to the young adult patients, DTC in children presents with more aggressive behavior, but outcomes are similar between the two groups after the intensive management of surgery followed by radioiodine and TSH suppression therapy.