• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.308-309
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• 2015

선형 이온빔 적용 플라즈마 표면처리 기술 및 코팅 공정을 통해서 고경도 투명 박막 형성 연구를 수행하였다. 플라즈마 전처리를 통해서 박막과 기판 사이의 밀착력을 향상시키고, advanced linear PECVD와 advaced plasma source를 적용하여 SiOxNy계의 박막을 형성하였다. 그 결과 투과도 92 % 이상, 표면 경도 6.3~6.9 GPa 이상의 고경도 투명 박막을 개발하였다. 본 연구 공정을 바탕으로 고경도의 투명 보호 필름 및 투명 디스플레이에 응용이 가능할 것으로 기대된다.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.4
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• pp.333-337
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• 2014

The purpose of this study is to develop a process technology to produce high hardness concentrated seawater removing chloride ions but containing useful minerals such as magnesium and calcium in the seawater desalination process. In order to make high hardness concentrated seawater, evaporation system is mostly used recently. Because evaporation system requires a large amount of energy consumption, in this study, it was aimed to produce high hardness concentrated seawater using membrane filtration requiring less energy. Nano filtration membranes were used for the experiments, and different types of high hardness concentrated seawater was produced depending on the membranes' specification, the number of times being concentrated, and pressure. As a result, at between 15bar and 20 bar in pressure, in between the second and the third times of concentration, the experiment result showed the best economic efficiency. By the experiment, production of high hardness concentrated seawater seemed to have a good economic feasibility.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.4
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• pp.301-312
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• 2022

In an extensive oral rehabilitation, determining a proper occlusal vertical dimension is a critical step and the starting point for successful treatment. Since changing the occlusal vertical dimension could be time-consuming, financially challenging, and physically demanding for both clinicians and patients, multi-faceted analysis and careful consideration are essential in the diagnosis and further treatment process. The purpose of this narrative review is to discuss the occlusal vertical dimension and its current issues, and to summarize previous methods of evaluating occlusal vertical dimension to propose clinical guidance for determining a viable occlusal vertical dimension for full-mouth rehabilitation.

• The korean journal of orthodontics
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• v.31 no.2 s.85
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• pp.187-197
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• 2001

The change of the vertical dimension is of fundamental importance to the orthodontist. However, the choice between the two methods of treatment, extraction versus nonextraction, is not clear. It is not verified that the extraction method decreases vertical dimension, or nonextraction methods result in an increase in vertical dimension. The purpose of this study was to evaluate the changes of vertical dimension of face after the orthodontic treatment with standard edgewise technique, and to compare them in relation to facial types and bicuspid extraction. The subjects consisted of 165 orthodontic patients (77 of adolescents, 88 of adults), and was divided into vertical nonextraction (VN) group, vertical extraction (VE) group, horizontal nonextraction (HN) group, horizontal extraction (HE) group. Pre-and Post-treatment cephalograms were taken with standard method, traced, and digitized for each subject. The comparison of the measurements were statistically executed with Student's t-test. The results were as follows : 1. The facial height and molar height were increased after orthodontic treatment in the all groups. 2. No significant difference was found in the facial height change between the vertical and horizontal groups. 3. No significant difference was found in the facial height change between the extraction and nonextraction groups. 4. As the upper molars were extruded in adolescents group and lower molars were extruded in adults group, lower anterior facial height (LAFH) was increased. 5. None of the pretreatment variables correlates to the change of lower anterior facial height (LAFH).

• The korean journal of orthodontics
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• v.29 no.3 s.74
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• pp.339-347
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• 1999

The purpose of this study was to investigate the variations of the skeletal and dentoalveolar dimensions in relation to vertical facial patterns. Lateral cephalogram of 200 cases (100 cases of male and 100 cases of female, average age of which was 23.2 years) were traced and some measurements of skeletal and dentoalveolar dimensions were measured. The ratio of UAFH/LAFH was employed to classify the samples into groups of excess and short lower anterior facial height. And the comparison between two groups were taken statistacally. The following results were obtained. 1. The dentoalveolar height, lower anterior facial height, lower genial angle, and FMA in the excess-lower-anterior-facial-height group were significantly larger than those in short-lower-anterior-facial-height group. 2. The dentoalveolar height, facial height, ramus height, and Jarabak ratio in the male subjects were significantly larger than those in the female subjects. 3. The UAFH/LAFH ratio showed a significant correlation to upper, lower facial height, AUDH, PUDH, ALDH, PLDH, Lower gonial angle, FMA, and $Bj\"{o}rk's$ Sum.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2001.03a
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• pp.132-138
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• 2001

홍콩 HMRT(Hongkong Mass Railway Tunnel) 지하철 공사현장에서는 터널굴착시 나타난 고경사절리로 인해 상당한 여굴이 발생하였다. 이에 대한 원인을 규명하기 위하여 각 터널별로 발생한 여굴의 양과 위치 등을 조사하고 이를 입찰설계단계에서 이루어진 시추공조사와 굴착단계에서의 막장검측에 의한 지질조건과 서로 비교, 분석하였다. 터널굴착에서 발생하는 여굴은 막장의 고경사 절리의 분포와 방향에 의해 영향을 받았으며, 암반조건 RQD, Q'와도 밀접한 관계를 가지는 것으로 나타났다. 본 현장의 분석에 따르면 터널설계시 고경사절리의 존재여부 및 분포, 방향성 등을 면밀히 조사하고 해석하여 사전에 여굴의 발생 가능성을 확인하는 것이 필요하다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.92.1-92.1
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• 2017

고경도 질화막 합성과 밀착력 향상을 위한 기판 청정 기술은 밀접한 상관관계가 있다. 음극 진공 아크 증발원을 이용하여 기판 청정을 실시하였으며, 기판 전압이 증가함에 따라 기판 청정 효과가 증가하였으나, 그 역효과 또한 확인할 수 있었다. 특히 기판 전압 인가부의 전극 접촉부 위치에 따라 청정 형상이 크게 영향을 받음을 확인하였다. 기판 청정 후 고경도 질화막을 형성시켜 100N 이상의 밀착력 확인하였다.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.1
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• pp.56-63
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• 2018

Severe dental attrition causes pathological changes of the tooth, collapsed occlusion, and functional and aesthetic complications and can also result in a decrease in occlusal vertical dimension. Before increasing the vertical dimension with full-mouth rehabilitation, it is important to determine the amount of vertical dimension through accurate diagnosis. In this case, a 77 year old elderly male patient on anticoagulant medication with generalized attrition and fracture of teeth was treated with full-mouth rehabilitation in order to recover vertical dimension and aesthetics. Accurate clinical and radiographic examination, diagnostic, wax-up, and occlusal vertical dimension evaluation were step by step performed considering pre-medical history and old age. Patient adaptability was evaluated using an occlusal splint and interim restoration. After 3 months of stabilization with interim restoration, definitive prostheses were fabricated. Satisfactory functional and esthetic outcomes are observed after 6 months of follow up.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.4
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• pp.315-323
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• 2014

Excessive teeth abrasion causes pathologic changes of oral environment and masticatory system due to decrease in occlusal vertical dimension. When establishing new occlusal plane and recovering vertical dimension, accurate diagnosis and analysis are essential. In this case, after appropriate centric relation in elevated vertical dimension was taken using Gothic arch tracer, full mouth rehabilitation was performed. A 70-year-old male patient had the chief complaint that he could not eat due to teeth wear. He showed generalized teeth wear and decreased vertical dimension. Elevation of vertical dimension was planned by model analysis. According to increased vertical dimension, centric relation was recorded using Gothic arch tracer and temporary prostheses were applied. Appropriate occlusion was established by temporary prostheses for 4 months. Final prostheses were fabricated using vertical dimension adapted by temporary prostheses. Through this procedure, satisfactory outcomes were achieved both in functional and esthetic aspects.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.1
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• pp.103-108
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• 2006

Loss of permanent molar by multiple dental caries traumatic influence or hereditable disease can cause loss of the vertical dimension in children. However traditionally reconstructive treatment to restore vertical dimension in children has been provided by using simple methods such as celluloid crown form and stainless steel crown. The presented case report describes an alternative treatment modality of vertical dimension by using removalbe appliance This appliance is made with average of facial height and maximal clenching force by using T-scan.