• Journal of Pharmaceutical Investigation
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• 제26권3호
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• pp.155-168
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• 1996

The active site of cyclooxygenase was modeled by complementary receptor-cavity mapping procedure using 3D structures of the non-steroidal antiinflammatory drugs (NSAIDs). A total of 50 NSAIDs were chosen as data ligands which compete the same site on the enzyme. Partial atomic charges were estimated, and the energetic differences for various conformations were calculated so as to meet the need for a most efficient overlapping of the probably-equivalent functional groups of the ligand molecules. The structure activity relationships of the NSAIDs, if available, were fully considered throughout the modeling. The overall shape of the model obtained is similar to a boot-without-bottom. Most of inner surface of the cavity appeared as hydrophobic; two polar counterparts except the carboxyl-binding position were found. By this model, some clear explanations could be given on the experimental observations which were not satisfiably understood yet.

• 대한두경부종양학회지
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• 제10권2호
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• pp.163-170
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• 1994

Segmental mandibulectomy causes severe functional disability and cosmetic problem. Many methods of reconstruction have been used but none of these procedures provides the ideal solution. There has been increased interest in the possibility of preserving a portion of the mandible and still carrying out a adequate tumor resection. We experienced four cases of marginal with sagittal mandibulectomy in patients with floor of mouth. buccal. and soft palate carcinoma, and sagittal mandibulectomy in 8 patients with tonsillar carcinoma and a case of marginal mandibulectomy in tonsillar cancer patient. In all cases mandible facing the tumor were successfully resected and repair of the mandible. postoperative facial contour were satisfactory. We think. that these sagittal procedures are oncologically sound in its removal of tumor. biomechanically secure and maximize postoperative rehabilitation while maintaining the normal contour of the face.

• Geomechanics and Engineering
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• 제6권3호
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• pp.213-233
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• 2014

The present paper is dealing with the investigation of the stress field around the infinitely long cylindrical cavity, of a circular cross section, contained in the transversally isotropic elastic continuum. Investigation is based upon the determination of the stress function that satisfies the biharmonic equation, for the given boundary conditions and for rotationaly symmetric loading. The solution of the partial differential equation of the problem is given in the form of infinite series of Bessel's functions. Determination of the stress-strain field around cavities is a common requirement for estimation of safety of underground rock excavations.

• 소성∙가공
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• 제7권6호
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• pp.610-619
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• 1998

The superplastic blow forming technology has advantages of cost reduction and low material consumption. compared to the conventional sheet metal forming technology due to the capability of precisely forming with high elongation and low flow stress. however it has a disadvantage that its partial thickness distribution is non-uniform. A processing technology like diaphragm forming has been developed even though it is difficult to prepare materials for superplastic blow forming. in this study a hemisphere forming of sheet before superplastic forming. It was found that the rotary forming material was less in quantity of cavitation at pole than that of hemisphere part that was superplastic formed without rotary forming treatment. Also discussed are the critical strain which is closely related to cavity shape and size.

• 대한기계학회논문집
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• 제16권6호
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• pp.1179-1194
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• 1992

본 연구에서는 이 기존의 방법들을 개선하여 비균일격자계에서도 사용할 수 있는 비선형 함수관계를 제시하며, 이 방법과 기존의 해법들을 비교할 때 실제 유동장 에서의 해의 정확도 차이, 전산비용의 경제성등은 어느정도 인지를 밝히고, 또 개선된 해법이 앞서 제시한 좀 더 복잡한 유동장에서도 성공적으로 적용 가능한지의 여부를 판단하는 것을 그 목적으로 한다.

• 한국광학회지
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• 제10권4호
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• pp.311-317
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• 1999

다이오드 레이저 펌핑 Nd:YAG 레이저를 평면 반일체 고리형 공진기를 이용하여 1064 nm 파장에서 단방향, 단일 모드로 발진시켰다. 실험에 사용된 반일체 고리형 공진기는 자기장 내에 놓여진 Nd:YAG 레이저 활성매질, 결정 석영판, 출력경으로 구성되어 전체적으로 광 다이오드로서 작용한다. 이에 대한 고유편광 이론 연구가 수행되었으며, 고유편광 모드에 대한 광손실이 계산되었다. 1.2 W, 809 nm 다이오드 레이저로 펌핑하여 155 mW의 단일 모드 출력을 얻었으며, 이때의 기울기 효율은 17%이었다. 동일한 두 레이저 시스템이 제작되었는데, 그 출력들의 맥놀이 주파수 스펙트럼으로부터 100 kHz 이하의 레이저 선폭을 갖는 것으로 측정되었고, 2 GHz 이상의 영역에서 연속적인 주파수 튜닝이 관측되었다.

• Journal of Electrical Engineering and Technology
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• 제10권5호
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• pp.2089-2098
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• 2015

With the continuous development in insulation of electrical equipment design, the reliability of the system has been enhanced. However, in the manufacturing process and during operation under continues stresses introduce local defects, such as voids between interfaces that can responsible to occurrence of partial discharge (PD), electric field distortion and accumulation of charges. These defects may lead to localize corrosion and material degradation of insulation system, and a serious threat to the equipment. A model of three layers of PI film with air gap is presented to understand the influence of interface and voids on exploitation conditions such as strong electrical field, PD activity and charge movement. The analytical analysis, and experimental results are good agreement and show that the lose contact between interfaces accumulate more residual charges and in consequences increase the electric field intensity and accelerates internal discharges. These residual charges are trapped charges, injected by the electrodes has often same polarity, so the electric field in cavities increases significantly and thus partial discharge inception voltage (PDIV) decreases. Contrary, number of PD discharge quantity increases due to interface. Interfacial polarization effect has opposite impact on electric field and PDIV as compare to void.

• Journal of Chest Surgery
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• 제45권3호
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• pp.177-182
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• 2012

Background: Tuberculous abscess of the chest wall is a very rare disease. Few articles have reported on it and those that have enrolled few patients. To determine the characteristics of this disease and to suggest an optimal treatment strategy, we reviewed patients treated by surgical management. Materials and Methods: Between October 1981 and December 2009, 68 patients treated by surgical management for a tuberculous abscess of the chest wall were reviewed retrospectively. Results: Of 33 men and 35 women, 31 patients had a current or previous history of tuberculosis. The main complaints were chest pain, a palpable mass, pus discharge, and coughing. A preoperative bacteriologic diagnosis was performed in 12 patients. Abscess excision was performed in 54 cases, abscess cavity excision and partial rib resection in 13, and abscess excision and partial sternum and clavicle excision in 1 case. Postoperative wound infection was noted in 16 patients and a secondary operation was performed in 1 patient. Recurrence occurred in 5 patients (7.35%). Reoperation with abscess excision and partial rib resection was performed in all of the 5 cases. Conclusion: Complete excision of the abscess and primary closure of the wound with obliteration of space would decrease postoperative complications. Anti-tuberculosis medication may reduce the chance of recurrence.

• 한국결정성장학회지
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• 제31권3호
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• pp.127-136
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• 2021

This paper is dedicated to numerical simulation for diffusion-advective convection in a square cavity during physical vapor transport of Hg₂Br₂. Flow characteristics of the temperature difference between the source and crystal regions, 50℃ (300℃ → 250℃), partial pressures of component argon of 20 Torr and 100 Torr are investigated and presented as velocity vectors and streamlines, isotherms and iso-mass concentrations contours. Moreover, alterations of average Nusselt and average Sherwood numbers with (a) the source and crystal regions, (b) the pressures of component argon of 20 Torr and 100 Torr are analyzed and addressed in details. Both average Nusselt and average Sherwood numbers are seen to decrease with the increasing values of the partial pressures of component argon. Also, it is found that for the two different partial pressures of component argon, average Nusselt numbers at the source region are greater than at the crystal region, and inversely, average Sherwood numbers at the crystal region are greater than the source region by a factor of 3.

• 대한두경부종양학회지
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• 제17권2호
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• pp.179-184
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• 2001

Objective: The role of chemotherapy in locally advanced head and neck cancer has been established in nasopharynx and larynx as definitive therapy and organ preserving therapy, respectively. Oral cavity cancers are relatively uncommon and local recurrence is the main cause of treatment failure. We planned this retrospective study to evaluate the role of neoadjuvant chemotherapy in locally advanced oral cavity cancer patients. Materials and Methods: From 1988 March to 2001 February, locally advanced, previously untreated oral cavity cancer patients who received neoadjuvant chemotherapy were examined. Chemotherapy had been done in the following patients: Histologically proven squamous cell or poorly differentiated carcinoma, stage 3 or 4, and performance state 0-2 patients. Chemotherapy regimen consisted of cisplatin and infusional 5-fluorouracil. Response was evaluated after 2 cycles and in case of no response, definitive local therapy was done; otherwise 3 cycles was done before local treatment. Results: 48 patients were treated and 47 patients were evaluable for responses. Complete response rate was 6.4%(3/47) and partial response 80.0%(38/47), scoring overall response rate of 87.2%. Median time to progression was 27.0 months (95% CI : 0-58months) and overall 5 year survival was 54.8%. 5-year disease-free survival in the patients in remission after local treatment was 51.9%. In multivariate analysis, contributing factor to the survival were response to neoadjuvant chemotherapy and local treatment modalities. Extensive surgery was done in 10 patients and 25 patents (52.1%) was followed up with preserved function. With median follow-up of 57.0 months, 19 recurrences were detected, most of which were local or regional type. Conclusion: Neoadjuvant chemotherapy followed by local treatment in oral cavity cancer showed high response rate and was thought to be effective therapeutic approach especially in view of organ preservation.