• The Journal of Korean Academy of Prosthodontics
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• v.61 no.1
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• pp.1-17
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• 2023

Purpose. The purpose of this study was to examine the correlation between the finish line designs and the marginal adaptation of nonprecious metal alloy coping produced by different digital manufacturing methods. Materials and methods. Nonprecious metal alloy copings were made respectively from each master model with three different methods; SLS, milling and casting by computer aided design and computer aided manufacturing (CAD-CAM). Twelve copings were made by each method resulting in 72 copings in total. The measurement was conducted at 40 determined reference points along the circumferential margin with the confocal laser scanning microscope at magnification ×150. Results. Mean values of marginal gap of laser sintered copings were 11.8 ± 7.4 ㎛ for deep chamfer margin and 6.3 ± 3.5 ㎛ for rounded shoulder margin and the difference between them was statistically significant (P < .0001). Mean values of marginal gap of casted copings were 18.8 ± 20.2 ㎛ for deep chamfer margin and 33 ± 20.5 ㎛ for rounded shoulder margin and the difference between them was significant (P = .0004). Conclusion. Within the limitation of this study, the following conclusions were drawn. 1. The variation of finish line design influences the marginal adaptation of laser sintered metal coping and casted metal coping. 2. Laser sintered copings with rounded shoulder margin had better marginal fit than deep chamfer margin. 3. Casted copings with deep chamfer margin had better marginal fit than rounded shoulder margin. 4. According to the manufacturing method, SLS system showed the best marginal fit among three different methods. Casting and milling method followed that in order.

• Journal of Electrical Engineering and Technology
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• v.2 no.4
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• pp.494-499
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• 2007

In this paper, we have investigated how transmission network constraints can be modeled in an electricity market equilibrium model. Under Cournot competition assumption, a game model is set up considering transmission line capacity constraints. Based on locational marginal pricing principle, market clearing is formulated as a total consumers# benefit maximization problem, and then converted to a conventional optimal power flow (OPF) formulation with a linearized transmission model. Using market clearing formulation, best response analysis is formulated and, finally, Nash equilibrium is formulated. In order for illustration, a numerical study for a four node system with two generating firms and two loads are presented.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.1
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• pp.41-47
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• 2007

Transmission Loss Factor (TLF) is one of the key factors affecting transmission pricing which should capture the intrinsic characteristics of competitive electricity markets and be amenable to the agreement of the market participants. This paper proposes a practical methodology which enhances the utility and applicability of TLF which is vulnerable to the choice of slack bus, computation methodologies, and incremental generation (or incremental load). The proposed methodology is demonstrated with a case study.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.113-114
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• 2007

For restructure of korean power system, we needs research and development concerning RTP and Revenue Reconciliation. In these Implementations the real-time prices are updated at half-hourly or hourly intervals and in no case are the prices spatially differentiated. The implemented rates are based upon marginal generating costs with markups to account for system transmission and distribution costs or other revenue reconciliation needs. This paper analyzes how great is the impact of alternative price markup methods on measures of social welfare and customer responses. A case study and energy sales are also presented.

• The Journal of the Korean bone and joint tumor society
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• v.1 no.2
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• pp.194-199
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• 1995

To evaluate the role of post-operative irradiation in reducing local recurrence after surgical treatment of liposarcoma, 19 patients who were treated between July 1988 and June 1994 at Department of Orthopedic Surgery, Catholic University were studied retrospectively. The average follow up was 31 months. 1. There were 14 males and 5 females and an average age was 51 years old. 2. Thirteen cases were in extremities and buttock, 3 in neck, 2 in retroperitoneum and 1 in back. 3. Histologic types were 16 cases of myxoid type and 3 cases of well differentiated type. 4. Ten cases were achieved with wide margin and 9 with inadequate(intralesional or marginal) margin. 5. There were no local recurrence in 10 cases with wide margin, whereas 6(67%) local recurrences in 9 cases with inadequate margin. 6. Among 6 cases of local recurrence, 5 cases had been treated with post-operative irradiation. In conclusion, post-operative irradiation for inadequate margin(intralesional or marginal margin) was not sufficient to reducing local recurrence.

• Tuberculosis and Respiratory Diseases
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• v.63 no.2
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• pp.194-199
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• 2007

BALT(bronchial associated lymphoid tissue) lymphomas are a distinct subgroup of low-grade B-cell extranodal non-Hodgkin's lymphoma, which are classified as a marginal-zone lymphomas. The majority of the patients are asymptomatic or their pulmonary lesions is often discovered incidentally on a routine chest radiograph. A 50-year-old man was admitted for an the evaluation of cough, dyspnea and fever. His chest CT showed ground glass appearance with interlobular septal thickening in both lower lobes, right middle lobe and left lingular division. He had been initially diagnosed with lipoid pneumonia and was kept under observation. However, his chest lesion showed continuous progression and a video-associated thoracoscopy was performed His pulmonary lesion was confirmed histologically to be a BALT(bronchial associated lymphoid tissue) lymphoma. We report a case of a BALT lymphoma, which was initially misdiagnosed as lipoid pneumonia.

• Archives of Plastic Surgery
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• v.34 no.2
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• pp.261-264
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• 2007

Purpose: Extranodal marginal zone B cell lymphoma of MALT type represents approximately 8% of non-Hodgkin's lymphomas and this lymphoma is present in extranodal sites. Although the presentation of this lymphomain in stomach is usually associated with H. pylori infection in 95% of cases, MALT lymphoma found in soft tissue has been reported very rarely in the field of plastic surgery. We report a case of MALT lymphoma in the submandibular gland without any involvement of other organs such as the stomach. Methods: A 49-year-old man complained of a huge neck mass sized about $10{\times}12cm$. It started about 2 years ago and grew rapidly for the late 6 months. It was of hard nature with erythematous skin overlying it. Under the diagnosis of possible malignant lymphoma or sarcoma, radical resection was performed and the defect was reconstructed using transverse rectus abdominis musculocutaneous free flap. Results: The mass was well demarcated from the normal tissue, $11{\times}10.5{\times}10cm$ in size and whitish-gray color. Immunohistochemical analysis demonstrated that the tumor cells were LCA(+), CD20(+), CD3(-) and CD5(-). The tumor was diagnosed as extranodal marginal zone B cell lymphoma. The patient was treated with prophylactic radiation therapy after surgery, there was no complication for 1 year. Conclusion: We reported that very rare form of MALT lymphoma in 49-year-old male patient was experienced with clinical characteristics, histologic features and references.

• Tuberculosis and Respiratory Diseases
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• v.61 no.2
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• pp.171-177
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• 2006

Extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) is usually indolent. Although it was reported recently that about 20-30% cases of MALT lymphoma presented with a disseminated disease at diagnosis, it was described as a disease localized at diagnosis and remaining stable for a prolonged period. However, only a few cases of MALT lymphoma involved the lung and gastrointestinal tract all at once. We report a case of a 73-year-old man with disseminated MALT lymphoma. He presented with non-productive cough, initial chest radiograph showed a nodule in the right lower lobe. The diagnosis of stage IV MALT lymphoma was made by CT scan, video-assisted thoracoscopic excisional biopy, gastrofiberscopic biopsy and bone marrow biopsy. The lymphoma involved the lung, stomach and bone marrow at the time of diagnosis. Because he refused chemotherapy, he discharged after Helicobacter pylori eradication without chemotherapy. Regular follow-up examination did not show any evidence of disease progression over 22 months.

• Korean Journal of Head & Neck Oncology
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• v.31 no.1
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• pp.34-38
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• 2015

Progressive transformation of germinal centers(PTGC) is a rare benign lymph node enlargement characterized by chronic lymphadenopathy and the presence of germinal centers with fused and expanded mantles within a lymph node that are 3-5 times the size of a typical reactive follicle. Although PTGC is reported in 3.5-10% of chronic lymphadenopathy, head and neck surgeons do not often experience this condition and its clinical implications. Althoug PTGC is benign disease, it could not be excluded the association with other malignant lymphoid diseases. Therefore, periodic follow up of PTGC patient could be required. We report two cases at this study ; a 16 years old man who visited out-patient clinic due to palpable mass of right cervical area, several months ago, and a 35 years old man who visited out-patient clinic for evaluating right cervical mass. Both of two patients were diagnosed with PTGC. In this study, we focus on the clinic-pathologic features of this uncommon disease along with other literature reviews.

• The Journal of the Korean bone and joint tumor society
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• v.13 no.1
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• pp.55-59
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• 2007

Synovial chondroma is an uncommon benign lesion characterized by metaplastic cartilage formation within the synovial connective tissue, usually intraarticular, commonly affects the knee, hip and elbow. We would like to present the case of a 65-year-old man suffering from synovial chondroma of the right elbow responsible for radial nerve entrapment neuropathy. This is a case of synovial chondroma of the right elbow in an 65-year-old man presenting with pain and restricted joint movement of the right elbow, loss of extension and sensation of the right thumb and wrist. Plain radiographs showed narrowing of elbow joint space, bony spur on the edge of the joint, and radio-opaque sclerotic change of subchondral area. MRI revealed $16{\times}12$ mm sized round mass on the radial head, homogenous low signal on T1WI, heterogenous high and low signal on T2WI. The patient underwent marginal excision of the mass, compressing the radial nerve. Diagnosis was confirmed by histologic examination.