• 지질공학
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• 제15권3호
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• pp.257-268
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• 2005

일반적으로 현지 암반은 강도의 변화가 심 한 다양한 불연속면들을 포함하여 불균질하고 불연속성 을 나타낸다. 절리, 단층, 균열, 층리와 같은 불연속면들은 암반의 강도와 변형특성을 좌우하는 중요한 요인이다. 결과적으로, 지하공동의 안정성은 무결암의 역학적 특성뿐만 아니 라, 공동의 기하학적 형상과 관련하여 불연속면들의 공간적 분포와 역학적 특성에 크게 영 향을 받는다. 따라서 지하심부의 응력 조건에서의 공동설계를 위해서는 불연속 암반의 거동에 대한 정확한 이해가 필수적이다. 암반역 학 분야의 발전에 의하여 등방성 암반에서 의지 하공동 설계를 위한 기준이 제시되고 있으나, 불연속성 암반의 변형 거동은 불명확성 이 여전히 존재한다. 본 연구에서는 연속체절 리모델을 적용하여 불연속성 암반내의 지하공동 주변의 소성영역의 크기, 응력분포 및 변형거동에 대하여 매개변수의 변화에 따른 영향을 고찰하였다. Mohr-Coulomb 파괴 이론에 의한 탄소성 유한차분법을 적용하였으며, 비조합 유동법칙과 완전소성 물질거 동을 가정하였다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제18권2호
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• pp.298-307
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• 1996

Osteochondroma is a common benign tumor of the axial skeleton, especially the distal metaphysis of the femur and the proximal metaphysis of the tibia, however, is occurred rarely on the facial skeleton. Development of the tumor is most frequently seen in the second or third decades of life. Typically, it arises directly from the cortex of the underlying bone, without any intervening zone of abnormal osseous tissue, and is covered by a cap composed of cartilage undergoing calcification. In case of osteochondroma of the mandibular condyle, its clinical features are occulusal change, facial asymmetry, headache, pain and click on temporomandibular joint, mouth opening limitation, and jaw deviation to involved site. This is a case report of a 13-year old woman who had mouth opening limitation and severe temporomandibular joint pain. We obtained successful results with surgical removal of the osteochondroma on the mandibular condyle.

• Structural Engineering and Mechanics
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• 제74권2호
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• pp.243-254
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• 2020

Devastating RC structural failures in the past have identified that the behavior of beam-column joints is more critical and significantly governs the global structural response under seismic loading. The congestion of reinforcement at the beam-column joints with other constructional difficulties has escalated the attention required for strengthening RC beam-column joints. In this context, numerous studies have been carried out in the past, which mainly focused on jacketing the joints with different materials. However, there is no comparative study of different approaches used to strengthen RC beam-column joints, from efficiency and cost perspective. This paper presents a detailed investigation carried out to study the various strengthening schemes of exterior RC beam-column joints, viz., steel fiber reinforcement, carbon fiber reinforced polymer (CFRP) strengthening, steel haunch strengthening, and confining joint reinforcement. The effectiveness of each scheme was evaluated experimentally. These specimens were tested under horizontal loading that produced opening moments on the joints and their behavior was studied with emphasis on strength, displacement ductility, stiffness, and failure mechanism. Special attention was given to the study of crack-width.

• Journal of Oral Medicine and Pain
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• 제24권4호
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• pp.455-466
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• 1999

The purpose of this study was to investigate the magnitude of mandibular rotational torque movements in subjects with TMJ sounds, and to analyse correlation between quantitative characteristics of TMJ sounds and mandibular rotational torque movement. Twenty dental college students with TMJ clicking and twenty students without any TMD signs and symptoms were examined by mean of SonoPak and Rotate program of BioPAK system(Bioresearch Inc. MilWaukee, wisconsin, USA) in this study. Mandibular rotational torque movements were recorded and analysed during maximum mouth opening, protrusion, and lateral excursion in frontal and horizontal planes. The obtained results were as follows: 1. On maximum mouth opening, mandibular rotational angle and distance of clicking group were significantly greater than those of control group in frontal plane. (P<0.05). 2. During maximum mouth opening closing, maximum mandibular rotational angle and distance of clicking group were significantly greater than those of control group in frontal plane. (P<0.01). 3. On protrusion, mandibular rotational angle and distance of clickin group were significantly greater than those of control group in horizontal plane. (P<0.05). 4. On lateral excursion, there was no significant difference in mandibular rotational angle and distance between clicking group and control group in frontal and horizontal planes. 5. There were significant correlations between peak amplitude of TMJ sounds and maximum mandibular rotational distance during maximum mouth opening (r=-.481) and mandibular rotational distance on maximum mouth opening (r=-.455) in horizontal plane. 6. There were significant correlations between Above 300/(0-300)Hz ratio of TMJ sounds and mandibular rotational angle (r=-.499) and distance (r=-.457) on maximum mouth opening in frontal plane.

• 대한구순구개열학회지
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• 제7권2호
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• pp.133-139
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• 2004

Congenital bilateral idiopathic hyperplasia of the coronoid processes presents with limited mouth-opening without visible maxillofacial deformity or temporomandibular joint dysfunction / disorder. According to Blanchard et al and McLoughlin et al, it was lnitially described in 1853 by Langenbeck, and the first cases were reported by Holmes in 1956. Since then, there have been regular reports of a certain number of cases. In 1995, McLoughlin et al recorded 79 published cases of bilateral hyperplasia of the coronoid processes. Among them, Fabie et al have found only 3 published cases relating to children younger than 8 years, and have presented the first case of objectively diagnosed restricted mouth opening from birth by pediatricians. Authors have experienced 2 child patients with mouth opening limitation who was diagnosed congenital bilateral idiopathic hyperplasia of the coronoid processes without any other TNJ morphology in Dept of Oral and Maxillofacial surgery, Seoul National University Dental Hospital in 2004. Coronoidectomy was performed and postoperative active mouth opening exercise is indicated. Authors report 2 cases of congenital bilateial idiopathic hypeiplasia of the coronoid processes with literature liview.

• Journal of Oral Medicine and Pain
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• 제22권1호
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• pp.167-181
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• 1997

The aim of this study was to investigate the relationship between velocity and factors which could affect the velocity of mandibular movement. For this study, 30 dental students without any masticatory signs and symptoms and 90 patients with temporomandibular disorders(TMD) were selected as the control group and the patients group, respectively. After determining Angle's classification and lateral guidance pattern of occlusion, clinical examination for TMD was perfomed. Velocity and distance of mandibular movements were recorded with BioEGN, reproducibility index of lateral excursions was evaluated by Pantronic(PRI) and BioEGN (BERI) activity in masticatory and cervical muscles were measured with BioEMG, and occlusal contact time and cross-arch unbalance(Total left-right statistics, TLR) on clenching were recorded with T-scan, respectively. The results of this study were as follows : 1. Velocity in the patients was faster than that in the controls in most mandibular movements, but on wide opening and closing movement, result was reverse. 2. Velocity on closing movements were faster than that on opening movements in the control group and a similar tendency was also shown in the patients group. 3. Patients with muscle disorders showed a tendency to have the highest value of velocity of all diagnostic subgroups, while patients with degenerative joint diseases showed a tendency to have the lowest value. 4. Patients with canine guidance showed a tendency to have the highest value of velocity in three subgroups by lateral guidance pattern, while patients with group function showed a tendency to have the lowest value. 5. BERI had a positive correlation with opening velocity on lateral excursion, while TLR had a negative correlation with opening velocity on swallowing. 6. EMG activity on clenching in masticatory muscles had negative correlation with opening velocity on border movements, and on swollowing, while the activity in rest correlated positively with opening velocity on border movements. 7. There were positive correlation between the velocity and the distance in long components of mandibular trajectory.

• International journal of advanced smart convergence
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• 제10권1호
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• pp.117-124
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• 2021

Based on a result of we research and analysis of this study, it was analyzed that the average annual cremators number using E-Haneul Funeral Information System among the five public cremation facilities in Jeollabukdo was 9,713 in total before the opening of public creation facilities in Jeongeup City (2013-2015), while the number was 12,159 after the opening of public cremation facilities in Jeongeup City (2016-2019); the number was increased by 2,446, compared to the opening period (2013-2015), with a large increase rate of 25.2%. In addition, the average annual cremation rate before the opening of public cremation facilities in Jeongeup City (from 2013 to 2015) was 71.6%, but the average annual cremation rate during the period after the opening (from 2016 to 2019) was 81.5%, which was a large increase rate of 9.9% compared to period before the opening of the facilities. Based on research results above, we have presented policy suggestions in order to increase the efficiency of operation and management of public cremation facilities by local governments as follows. First, in order to prepare for the increase in demand for cremation due to the increase in cremators number, a policy promotion for the expansion of "public cremation facilities" should be carried out as soon as possible, focusing on local governments whose supply has reached the limit. Second, in order to support the expansion and construction of public cremation facilities, the government subsidy rate and government subsidy at the level of current 70%, provided by the central government, should be further expanded. Third, overcoming theNIMBY conflict overlocation for public cremation facilities, theutilization rate should be enhanced, through the joint construction and facility operation of the public cremation facilities between local governments, and the ef iciency of the project implementation should be improved through the jointsharing of the facility operation cost.

• International journal of advanced smart convergence
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• 제11권4호
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• pp.193-205
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• 2022

Based on the results of this study, we presented the following policy recommendations to improve the efficiency of operation and management of public cremation facilities. First, we findings the cremation number of all public cremation facilities in Gyeonggi-do increased from 39,918 people before the opening of public cremation facilities in Hwaseong to 55,642 people after the opening, showing a high rate of increase of 15,724 people(39.4%). Therefore, in order to increase the cremation ratio, the policy of expanding the supply of public cremation facilities should be actively pursued. Second, in this study we compared to before the opening of public cremation facilities in Hwaseong City, the ratio of cremation number the jurisdiction area of all public cremation facilities in Gyeonggi-do using the E-Haneul Funeral Information System increased by 19.0% from 35.9% to 54.9% after the opening, whereas it was analyzed that the outside of the jurisdiction area decreased by 19.0% from 64.1% to 45.1%. Therefore, in order to improve the convenience of citizens using the jurisdiction area, priority should be given to the promotion of policies for the establishment of public cremation facilities by local governments that do not have public cremation facilities. Third, through we research it is analyzed that the cremation ratio of the jurisdiction area of the public cremation facilities in Hwaseong City, which was jointly installed by six local governments located in Gyeonggi-do, was 92.4%, indicating that the ratio proportion of cremation number in the area is very high. Therefore, in order to improve the efficiency of the operation of public cremation facilities, the promotion of policies for joint installation and operation of public cremation facilities should be encouraged.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제40권4호
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• pp.155-159
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• 2014

Objectives: The purpose of this article is to evaluate factors influencing prognosis of arthrocentesis in patients with temporomandibular joint (TMJ) disorder. Materials and Methods: The subjects included 145 patients treated with arthrocentesis at the Dental Center of Ajou University Hospital from 2011 to 2013 for the purpose of recovering mouth opening limitation (MOL) and pain relief. Prognosis of arthrocentesis was evaluated 1 month after the operation. Improvement on MOL was defined as an increase from below 30 mm (MOL ${\leq}30mm$) to above 40 mm (MOL ${\geq}40mm$), and pain relief was defined as when a group with TMJ pain with a visual analog scale (VAS) score of 4 or more (VAS ${\geq}4$) decreased to a score of 3 or more. The success of arthrocentesis was determined when either mouth opening improved or pain relief was fulfilled. To determine the factors influencing the success of arthrocentesis, the patients were classified by age, gender, diagnosis group (the anterior disc displacement without reduction group, the anterior disc displacement with reduction group, or other TMJ disorders group), time of onset and oral habits (clenching, bruxism) to investigate the correlations between these factors and prognosis. Results: One hundred twenty out of 145 patients who underwent arthrocentesis (83.4%) were found to be successful. Among the influencing factors mentioned above, age, diagnosis and time of onset had no statistically significant correlation with the success of arthrocentesis. However, a group of patients in their fifties showed a lower success rate (ANOVA P=0.053) and the success rate of the group with oral habits was 71% (Pearson's chi-square test P=0.035). Conclusion: From this study, we find that factors influencing the success of arthrocentesis include age and oral habits. We also conclude that arthrocentesis is effective in treating mouth opening symptoms and for pain relief.

• 대한치과보철학회지
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• 제45권1호
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• pp.119-130
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• 2007

Statement of problem: A few dry lubricants were applied to abutment screws for the improvement of joint stability. Purpose: The purpose of this study was to evaluate the surface change and fit of TiN-Coated abutment screw through the examination of tested screws in the field emission scanning electron microscope(FE-SEM;Netherland, Phillips co., model:XL 30 SFEG) after repeated closing and opening. Materials and method: Titanium(3i/implant Innovations Inc, USA) and Gold-Tite abutment screws(3i/implant Innovations Inc, USA) were selected for Group A and C respectively. TiN coated titanium abutment screws were also divided into two groups, Group B and D. Abutment screws of each group and the fit of abutment screw/implant fixture/abutment were observed on FE-SEM after repeated closing and opening test respectively. Results: 1. The abutment screws of TiN coated groups(Group B and D) showed more remarkable wear resistance in the threads of the screw than those of the other group(Group A and C). 2. There were more severe wear and defect of TiN coating in Group D tightened to 32 Ncm than Group B to 20 Ncm. 3. There was no difference in the fit of abutment screw/fixture/abutment among four groups, Group A, Group B, Group C and Group D. Conclusion: Under the conditions of this study, it is suggested that TiN coating of abutment screw be clinically acceptable and be expected to reduce the risk of abutment screw loosening. TiN coating of abutment screw showed good resistance against wear and the adequate fit of abutment screw/implant fixture/abutment.