• Maxillofacial Plastic and Reconstructive Surgery
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• v.12 no.1
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• pp.135-141
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• 1990

Malignant Melanoma refers to a malignant neoplasm of melanocytes. Primary malignant melanoma of oral cavity is rare. Most frequent site of primary oral malignant melanoma are palate & gingiva. We have experienced 2 cases of malignant melanoma of the mouth. In one case, we performed wide surgical excision which was followed by chemotherapy with DTIC. In the other case, performed wide surgical excision only. There is no evidence of recurrence or of metastasis of the lesions 22 months, 12 months after operation, respectively.

• Journal of Electrical Engineering and Technology
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• v.3 no.3
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• pp.391-400
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• 2008

Multi-pulse topology of converters using elementary six-pulse GTO - VSC (gate turn off based voltage source converter) operated under fundamental frequency switching (FFS) control is widely adopted in high power rating static synchronous compensators (STATCOM). Practically, a 48-pulse ($6{\times}8$ pulse) configuration is used with the phase angle control algorithm employing proportional and integral (PI) control methodology. These kinds of controllers, for example the ${\pm}80MVAR$ compensator at Inuyama switching station, KEPCO, Japan, employs two stages of magnetics viz. intermediate transformers (as many as VSCs) and a main coupling transformer to minimize harmonics distortion in the line and to achieve a desired operational efficiency. The magnetic circuit needs altogether nine transformers of which eight are phase shifting transformers (PST) used in the intermediate stage, each rating equal to or more than one eighth of the compensator rating, and the other one is the main coupling transformer having a power rating equal to that of the compensator. In this paper, a two-level 48-pulse ${\pm}100MVAR$ STATCOM is proposed where eight, six-pulse GTO-VSC are employed and magnetics is simplified to single-stage using four transformers of which three are PSTs and the other is a normal transformer. Thus, it reduces the magnetics to half of the value needed in the commercially available compensator. By adopting the simple PI-controllers, the model is simulated in a MATLAB environment by SimPowerSystems toolbox for voltage regulation in the transmission system. The simulation results show that the THD levels in line voltage and current are well below the limiting values specified in the IEEE Std 519-1992 for harmonic control in electrical power systems. The controller performance is observed reasonably well during capacitive and inductive modes of operation.

• Archives of Craniofacial Surgery
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• v.12 no.2
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• pp.102-106
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• 2011

Purpose: It is accepted universally that correction of the cleft lip nasal deformity requires multiple stages of surgery. Following primary lip repair in infancy or early childhood, secondary surgery to improve the deformity of the lip and nose is frequently necessary. A suitable surgical procedure to correct the accompanying deformity, such as cleft palate and alveolus, must be carried out at an appropriate age. In developing countries, it is common for patients with cleft lip nasal deformity to present severe secondary deformities in adolescence, because of poor follow-up and inappropriate surgery. Methods: The first patient was a 12 year old Mongolian boy. He presented prominent lip scar, short lip, wide columella, asymmetric nostril, palatal fistula, cleft alveolus, and velopharyngeal incompetence. He underwent cheilorhinoplasty, transpositional flap, alveoloplasty by iliac bone graft, and sphincter pharyngoplasty. On follow-up, a bilateral maxillary hypoplasia and a class III malocclusion developed. He underwent LeFort I osteotomy and maxillary advancement at the age of 16 years. The second patient was an 18 year old Eastern Russian girl. She presented with a deviated nose, right alar base depression, short lip, protrusion on vermilion, large palatal fistula, and severe VPI due to short palate. She underwent the combined procedure of cheilorhinoplasty, corrective rhinoplasty, tongue flap for palatal fistula, and superiorly based pharyngeal flap. And the tongue flap was detached at postoperative 3 weeks. Results: The overall results have been extremely pleasing and satisfactory to patients. There were no postoperative complications. Conclusion: We discovered the one stage operation for radical correction was sufficient procedure to provide excellent clinical outcomes in patients with severe cleft lip nose deformity.

• Journal of the Korea Convergence Society
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• v.12 no.6
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• pp.1-8
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• 2021

The purpose of this study is to study the interaction structure of a smart farm for controlled environment horticulture. As a research method, interaction factors were analyzed by defining the growth stages of humans, plants, and plants, which are the subjects of interaction during the production, distribution, sales and consumption stages of smart farms. Additionally, on-site survey was used to differentiate between one-time, short-term, and long-term, depending on the behavior and operation of the interacting entity and time. As a result, the research came up to a finding that 1) Human and Plant are based on interactions of 'one-time, short-term' 2) Plant and Smart Farm as 'short-term' 3) Smart Farm and Human as 'short-term and long-term'. For this reason, this study is meaningful in deriving the relationship between the subjects and the interaction elements in the production stage of the smart farm and presenting a new interaction structure model by structuring them.

• The Journal of the Society of Stroke on Korean Medicine
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• v.9 no.1
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• pp.14-18
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• 2008

Objectives : This study was done to investigate the relationship of differentiation of the patten identification in stroke patients between acute and convalescent stage. Methods : In the time of period Apr. 1st 2007 to Sep. 29th 2008, 903 patients with stroke admitted in the department of Internal Medicine of Kyungwon University Oriental Medical Hospital, Kyunghee University Oriental Medical Hospital, Dongguk University Oriental Medical Hospital were included. Patients were hospitalized within a month after the onset of stroke. Stroke patients were interviewed by doctors who studied standard operation procedures. A questionnaire was completed by a question-and-answer form between patients and doctors after explanation details to patients and the agreement of patients. Results : The frequency of fire-heat patten was the highest in acute stage of stroke and the one of deficiency of Yin group was the highest in convalescent stage of stroke. This result doesn't have statistical significance. (p<0.05) Conclusions : In this study, we found the relationship of differentiation of the patten identification in stroke patients between acute and convalescent stage. Further, we have concluded that this difference should be considered in the management for stroke patients.

• Radiation Oncology Journal
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• v.12 no.3
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• pp.369-376
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• 1994

This is a retrospective analysis of 64 patients who was treated with postoperative radiation therapy after radical hysterectomy and bilateral pelvic lymphadenectomy (53 patients) or total abdominal hysterectomy(11 patients) for uterine cervix cancer between May 1980 and September 1991 at the Department of Radiation Oncology, Kyung Hee University Hospital. Most patients were FIGO IB (31 Patients) and IIA (25 patients), and median period of follow-up was 5.1 years. Of these patients,24 received adjuvant whole pelvis irradiation of 6000 cGy and 40 received 5000-5500 cGy whole pelvis irradiation and/or intracavitary radiation (7 Patients). The actuarial overall and relapse free 5 year survival rate were $71.0\%$, $68.3\%$ respectively. The survival rates by stage were $79.1\%$ in stage I, and $61.2\%$ in stage II. Treatment failure was noted in 18 of 64 patients ($28.1\%$), Iocoregional failure in 8 ($12.5\%$), distant metastasis in 8 ($12.5\%$), paraaortic node metastasis in 1 and one patient and concurrent locoregional and distant metastasis. The univariate analysis of prognostic factors affecting to overall survival rate represented lymph node status, the number and site of metastatic lymph node, parametrial invasion, the thichness of cervical wall invasion, and size of cancer mass. Histology, vessel invasion, endometrial extension, hemoglobin level. resection margin status, age, radiation dose were not significant prognostic factors. Complication relating to operation and postoperative radiation were variable according to radiation therapy method: 6000 cGy RT group 8/24($33.3\%$), 5000-5500 cGy+ICR 3/7 ($42.9\%$), 5000-5500 cGy external RT only group 3/33 ($9.1\%$). In conclusion, the results suggest that postoperative radiotherapy is necessary in high risk patients for locoregional control and improving survival rate, and higher dose does not improve results but only increases complication.

• Journal of IKEEE
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• v.23 no.3
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• pp.994-1002
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• 2019

In this paper, we propose the development of a power conversion system for electric power take-off (e-PTO) of agricultural electric vehicles. Most e-PTOs use commercial power $220V_{AC}$. A bidirectional power conversion system having a two-stage structure consisting of a DC-DC converter and a DC-AC inverter for supplying a high output voltage using a low battery voltage of an agricultural electric vehicle is suitable. we propose a power conversion system consisting of the one-stage dual active bridge (DAB) converter and the two-stage bidirectional full bridge inverter. In addition, we propose a soft start algorithm for reducing the inrush current generated by the link capacitor charging during the initial operation. A 3kW prototype system and its corresponding algorithms have been implemented to verify its effectiveness through experiments.

• Journal of Korean Foot and Ankle Society
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• v.8 no.1
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• pp.76-80
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• 2004

Purpose: We assessed the results of open treatment of anterior impingement syndrome of the ankle in elite level soccer players and concomitant injuries were idenfied. Materials and Methods: We retrospectively reviewed twenty one elite level soccer players diagnosed with anterior impingement syndrome who underwent open debridement between January 1997 and January 2002. All were men and the mean age at the operation was 21 years (range 16 to 27). The mean follow-up duration was 31 months (13 to 71). Concomitant abnormalities were idenfied through physical examination, bone scan and MRI. On a preoperative lateral radiograph, patients were classified according to McDermott's stage. Anteromedial or anterolateral approach was used at the operation and osteophyte was removed with osteotome and rongeur. When chronic ankle instability was accompanying, we performed Modified Brostrom-Gould procedure and for osteochondral lesion, multiple drilling was applied. The Ogilvie-Harris scoring system was used as a clinical scale to evaluate pain, swelling, stiffness and limitation of activity. The results were scored as excellent (15 to 16 points), good (13 to 14) and otherwise unsatisfactory. The time to return to full activity including sports activity was determined. Results: Eighteen of twenty one patients had an excellent outcome. Three patients were graded unsatisfactory and two of them abandoned their career due to the persistence of residual pain. Concomitant abnormalities were found including twelve cases of chronic ankle instability, three cases of osteochondral lesion and two cases of flexor hallucis longus tendinitis. Conclusion: Open debridement was successfully applied to the elite level soccer player with anterior impingement syndrome of the ankle. Considerable coexistence of other abnormalities such as chronic ankle instability may encourage us to consider additional operative procedure.

• Archives of Plastic Surgery
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• v.32 no.2
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• pp.199-204
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• 2005

The nose is the most prominent area of the face, therefore susceptible to trauma and skin cancer. When small sized defect is in nasal tip, it results in disturbance of the facial harmony even if replantation, composite graft, skin graft or median forehead flap has been used for the reconstruction. So it is needed that the best method reconstruction is performed according to the degree of defect or deformity. And at the same time the physiology and anatomy of nose were clarified and its aesthetic subunits were employed. How can we cover the about 3 cm sized nasal defect in nasal tip with cartilage exposure? At first, we can think forehead island flap is most appropriate. We performed 7 cases of the forehead island flap for reconstruction of the defect in nasal tip(4 cases: cancer, 3 cases: trauma) from March, 2001 to August, 2004. This result was satisfactory in the point of texture, color, donor scar, and there were no complication such as wound disruption, infection, flap atrophy, and hematoma. The advantages of forehead island flap are: 1) No injury of deep vessel and nerve, 2) control of shape and volume, 3) Short operation time, 4) primary closure of donor site, 5) one stage operation. Also, forehead island flap can cover the defect in nose where skin graft and local flap can not cover. But, operator always must take care for flap congestion and donor site scar. We thought forehead island flap is one of the best option of reconstruction of nasal tip defect.

• Archives of Plastic Surgery
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• v.40 no.4
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• pp.353-358
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• 2013

Background Robots have allowed head and neck surgeons to extirpate oropharyngeal tumors safely without the need for lip-split incision or mandibulotomy. Using robots in oropharyngeal reconstruction is new but essential for oropharyngeal defects that result from robotic tumor excision. We report our experience with robotic free-flap reconstruction of head and neck defects to exemplify the necessity for robotic reconstruction. Methods We investigated head and neck cancer patients who underwent ablation surgery and free-flap reconstruction by robot. Between July 1, 2011 and March 31, 2012, 5 cases were performed and patient demographics, location of tumor, pathologic stage, reconstruction methods, flap size, recipient vessel, necessary pedicle length, and operation time were investigated. Results Among five free-flap reconstructions, four were radial forearm free flaps and one was an anterolateral thigh free-flap. Four flaps used the superior thyroid artery and one flap used a facial artery as the recipient vessel. The average pedicle length was 8.8 cm. Flap insetting and microanastomosis were achieved using a specially manufactured robotic instrument. The total operation time was 1,041.0 minutes (range, 814 to 1,132 minutes), and complications including flap necrosis, hematoma, and wound dehiscence did not occur. Conclusions This study demonstrates the clinically applicable use of robots in oropharyngeal reconstruction, especially using a free flap. A robot can assist the operator in insetting the flap at a deep portion of the oropharynx without the need to perform a traditional mandibulotomy. Robot-assisted reconstruction may substitute for existing surgical methods and is accepted as the most up-to-date method.