• 대한치과교정학회지
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• 제12권1호
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• pp.7-14
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• 1982

In this study, effects of cyclophosphamide on the growth of the mandibular condyle head were investigated with Spraque-Dawley rats of the 28 days of age. Rats were devided into four groups. Three were used as experimental groups, and one as control. Each rat in experimental group was injected intraperitoneally with cyclophosphamide repeatedly three times, 20mg/kg for the first group, 40mg/kg for the second, and 60mg/kg for the third each time. Rats in control group were injected with physiological saline in the same method. Rats in each group were sacrificed at 5, 10, and 15 days following the last injection. The specimens were stained with H-E, toluidine blue, PAS, and alcian blue. The results were as follows; 1. In experimental group, with increasing the injection doses, the thickness of the condylar cartilage from the transitional zone to the hypertrophic zone became thinner than in control group. 2. Weaker metachromasia to toluidine blue and less positive reaction to PAS were seen. 3. In primary marrow cavity the fewer trabecular was formed, The direction of trabecular formation became obscuerer, and the lower density of bone was resulted in.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제17권3호
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• pp.214-219
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• 1995

Free grafting of oral mucosa for minor oral reconstruction was first described by Propper in ridge extension surgery. Situation calling for mucosal grafting procedures may relate to periodontal surgery, minor and major preprosthetic surgery, implant surgery, reconstruction in deformity cases after trauma, congenital cleft, gross atrophy and ablative tumor surgery. In the cases of 9 patients with mucosal defect of intraoral or orbital cavity after wide excision of tumor, preprosthetic surgery, and orbitoplasty, full-thickness mucosal graft were used to close a large defect. Four patients received buccal mucosal graft for preprosthetic surgery or orbitoplasty, one patient had benign tumor and the others had malignant tumors located on the palate or upper alveolus. Buccal mucosal graft donor site morbidity and trismus were minimal and healing of surgical defect was satisfactory. So we present the case with review of literatures.

• 대한기관식도과학회:학술대회논문집
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• 대한기관식도과학회 1981년도 제15차 학술대회연제순서 및 초록
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• pp.12.4-12
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• 1981

비강 및 부비동에 발생하는 반전성유두종은 극히 드문 양성종양으로 1854년 Ward가 처음으로 보고하였으며 이후 여러학자들에 의하여 본증이 논의되어왔으나 우리나라에서는 그 보고례가 몇례 없었다. 비강 및 부비동에 발생하는 반전성유두종은 진성종양으로 비용과 현저히 다르며 제거후에도 재발하는 경우가 많고 드물긴 하지만 악성으로 변하는 경우가 있다. 일단 반전성유두종으로 밝혀지게 되면 가능한 한 광범위하게 제거해줘야되며 계속적인 추적조사가 필요하다. 최근 저자들은 비출혈, 비폐색, 취각장애, 두통을 주소로 내원한 64세된 여자환자에서 좌측 상악등에 압박괴사를 초래한 반전성유두종 1례를 치험하였기에 문헌고찰과 아울러 보고하는 바이다.

• 한국표면공학회지
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• 제48권3호
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• pp.105-109
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• 2015

We studied emission characteristics of blue fluorescent multi-tandem OLEDs using $Al/MoO_x$ as charge generation layer(CGL). Threshold voltage for 2, 3, 4, and 5 units tandem OLEDs was 8, 11, 14 and 18 V, respectively. The threshold voltage in multi-tandem OLEDs was lower than multiple of 4 V for the single OLED. Maximum current efficiency and maximum quantum efficiency of single OLED were 7.6 cd/A and 5.5%. Maximum current efficiency for 2, 3, 4, and 5 units tandem OLEDs was 22.6, 31.4, 41.2, and 46.6 cd/A, respectively. Maximum quantum efficiency for 2, 3, 4, and 5 units tandem OLEDs was 11.8, 15.8, 21.8, and 25.6%, respectively. The maximum current efficiency and maximum quantum efficiency in multi-tandem OLEDs were higher than multiple of those for the single OLED. The intensity for 508 nm peak was changed and the peak wavelength was red shift by increase of tandem unit in electroluminescent emission spectra. These phenomena can be caused by micro-cavity effect with increasing of organic layer thickness.

• 한국의류학회지
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• 제15권4호
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• pp.373-380
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• 1991

In the previous paper, we already discussed about the factor effected upon the initial maximum value of heat flux ($q_{max}$). Thermal conductivity, thermal transmittance and surface air cavity of wool fabrics were examind and their correlation to the $q_{max}$ was also studied In this study, the other factor was examined which had on effect upon the qmaf of an objective measure of warm/cool feeling. It was studied that the qmax correlated to the surface sturucture parameters (compression, friction, smoothness, roughness, thickness and weight). It was concerned to the degree of warm/cool feeling when we touched hand on fabrics. We selected twenty sorts of pure wool woven fabrics for men's fall-winter cloth (all Wool). The conclusions are as follow; 1. There was a good correlation between the $q_{max}$ and the compression property. 2. The surface structure parameters, smoothness and roughness, made various effects on the $q_{max}$, when the samples touched on a thin copper plate. So, there was not a certain correla-tion to the $q_{max}$.

• 한국자동차공학회논문집
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• 제6권6호
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• pp.24-30
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• 1998

A directly coupled Boundary Element and Finite Element Model was applied to the dynamic analysis of a coupled acoustic silencer with vibratory wall. In this cupled BEM-FEM muffler model, the BEM model was used to discretize the acoustic cavity and the FEM model was used to discretize the vibratory wall structure. Then the BEM model was coupled with the FEM model. The results of the coupled BEM-FEM model for the dynamic analysis of the simple expansion type reactive muffler configurations with flexible walls were verified by comparing the predicted results to analytical solutions. In order to investigate the effects of the muffler's structural flexibility on its transmission loss(TL) characteristics, the results of the coupled BEM-FEM model in conjunction with the four-pole parameter theory were utilized. The muffler's TL characteristics using the BEM-FEM coupled model with flexible walls as compared to other muffler configurations was studied. Finally the muffler's TL values with respect to different wall's thickness are predicted and compared.

• 소성∙가공
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• 제7권6호
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• pp.554-561
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• 1998

This paper describes a research work of developing a computer-aided design of lead frame semicon-ductor with piercing operation which is very precise for progressive working. An approach to the sys-tem is based on to knowledge-based rules. Knowledge for the system is formulated from plasticity theories experimental results and the empirical knowledge of field experts. This system has been writ-ten using AutoLISP to AutoCAD on a personal computer and is composed of three main modules which are input and shape treatment production feasibility check and strip-layout module. Based on the knowledge-based rules the system is designed by considering several factors such as material and thickness of product complexities of blank geometry and punch profile, and availability of press. Also strip-layout drawing generated by piercing operation according to punch profiles considered V-notch dimple. pad chamfer spank cavity punch camber and cross bow of lead frame is displayed in graphic forms. This system can be used by a novice who may not have any knowledge of tool design and will invrease efficiencies to the designer in this field.

• 대한기계학회논문집B
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• 제20권3호
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• pp.1083-1095
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• 1996

Shock wave/boundary layer interaction frequently causes the shock wave to oscillate violently and thus the global flow field to unstabilize. In order to stabilize the shock wave system in the diffuser of a supersonic wind tunnel, the present study attempted to control the shock oscillations by using a passive control. A porous wall with the porosity of 19.6% was mounted on a shallow cavity. Experiment was made by means of schlieren optical observation and wall pressure measurements. The flow Mach number just upstream the shock system and Reynolds number based on the turbulent boundary layer thickness were 2.1 and 1.8 * 10$\^$6/, respectively. The results show that the present passive control method on the shock wave/boundary layer interaction in the supersonic diffuser can significantly suppress the oscillations of shock system, especially when the shock system locates at the porous wall.

• 대한두개안면성형외과학회지
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• 제12권1호
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• pp.37-42
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• 2011

Purpose: Cancer arising from the external auditory canal is a rare disease. A lesion that seems harmless in someway, can be lethal when inadequately excised, the tumor may infiltrate nerves, the parotid and auditory tissues before re-invading the skin. Wide resection of the lesion surrounding the structure and reconstruction with an adequate plan is crucial for the treatment of this disease. Methods: Two patients with external auditory canal cancer were treated with muscle flaps and skin grafts. Lateral temporal bone resection (LTBR) was performed for complete resection of the cancer. The defect cavity was obliterated with highly vascularized tissue using pedicled sternocleidomastoid muscle, and temporalis muscle individually, combined with full thickness skin graft for covering the skin defect of the ear. Results: Clear resection margin was obtained, and both patients showed disease free survival during the follow up. There was no complications of hematoma, infection, flap loss, or wound problem in both patients. Both patient received radiation therapy, there was no osteoradionecrosis or any other complication related to radiation therapy. Conclusion: Utilizing pedicled muscle flaps for managing defects after wide resection of the external auditory canal cancer is an effective method for managing this difficult disease.

• 한국방사선학회논문지
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• 제6권5호
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• pp.365-371
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• 2012

암환자의 방사선 치료기술은 3D-CRT, IMRT, Tomotherapy로 발전해 가고 있으며 이 3가지의 치료법은 임상에서 가장 많이 쓰이는 방사선 치료기술이다. 본 연구에서는 3D-CRT, IMRT(Linac Based) 그리고 Tomotherapy 치료시 정상조직과 종양조직의 선량분포를 비교해 보고자 한다. 실험방법으로는 조직 등가물질로 이루어진 인체모형팬톰 (Anthropomorphic Phantom)을 대상으로 CT simulation을 실시(Slice Thickness : 3mm)하여 획득된 영상에 GTV를 비인두 부위로 정하고 PTV는 GTV에 2mm정도의 영역을 포함시켜 치료계획용 장비(ADAC-Pinnacle3. Tomotherapy Hi-Art System)으로 전송한다. 치료계획은 PTV의 처방선량을 7020 cGy로 설정한 후 PTV에 부여되는 선량값과 정상조직인 이하선, 구강, 척수에 흡수되는 선량값을 산출하였다. 실험결과 PTV에 분포된 선량값은 Tomotherapy, Linac Based - IMRT, 3D-CRT가 각각 6923 cGy, 6901 cGy, 6718 cGy의 선량분포를 보여 종양조직 처방선량값인 7020 cGy의 95%이상 부여되어 종양제어측면(TCP)에 부합하였으며 정상조직(이하선, 구강, 척수)은 각각 1966 cGy (Tomotherapy), 2405 cGy(IMRT), 2468 cGy(3D-CRT)[이하선], 2991 cGy(Tomotherapy), 3062 cGy(IMRT), 3684 cGy(3D-CRT)[구강], 1768 cGy(Tomotherapy), 2151 cGy(IMRT), 4031 cGy(3D-CRT)[척수]의 선량이 분포되었으며 이는 정상조직 합병증발생율(NTCP)의 선량을 넘지 않았다. 모든 치료기법에서 종양조직과 정상조직이 선량분포측면에 부합하였다. 3D-CRT의 치료법이 선량분포 면에서 가장 양호하지 않았지만 종양조직제어율(TCP)과 정상조직합병증율(NTCP)을 고려해 볼 때 기준치를 벗어나지 않는 선량이 분포 되었다. 상대적으로 선량분포가 우수한 Tomotherapy, IMRT는 오랜 치료시간 때문에 폐쇄공포증환자나 호흡불량 환자가 치료받는데 어려울 수 있다. 특히 토모테라피의 경우 치료 전에 고에너지 컴퓨터 단층촬영을 매일 실시하기 때문에 불필요한 방사선 피폭을 초래할 수 있다. 결론적으로 Tomotherapy가 선량분포에서 가장 우수한 치료기법으로 평가되었으며, IMRT, 3D-CRT의 순으로 방사선치료의 적합성을 보였다. 하지만 실제 치료시 환자의 상태에 따라 제한적으로 3차원 입체조형치료를 시행하여도 무방하다고 사료된다.