• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1383-1388
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• 2010

The latest generation of tram is low-floor design, various nations in europe and japan have developed battery driven hybrid trams that combine battery and wiring. Battery driven tram system is achieved by contactless power supply system, thus system is needed high efficiency, high power and low weight traction motor for maximization of energy efficiency. Research from abroad is still in induction motor(IM) application, and it is not meet the efficiency and the power per unit volume in IPMSM. In this paper, we design compare IM and IPMSM to apply battery driven tram, and then compare these motors. To design the motor, we estimate the loading condition at first. Loading condition includes rolling resistance, air-drag resistance, and slope resistance. Based on the loading condition by estimation, we determine the power and compute rated voltage and rated current. In this paper, voltage is limited by battery voltage level. As a result, volume about IM is 1.98 times bigger than IPMSM under same condition. Even though IPMSM is bigger than IM in power density per volume, we consider more factors for actual application because there are demagnetization of permanent magnet in IPMSM and so on by external environment conditions.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.2303-2308
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• 2010

We studied the cost-volume supply characteristic of public transportation systems focused on Bi-modal Tram in the main cities to analyze the applicability and status for the new transit system Bi-modal Tram as public transportation system. The operation cost considering the characteristic of vehicle, facilities, operation and average cost for respective public transportation system and the time cost considering the travel and transfer time are defined to the social cost, and the cost-volume supply curve is based on this social cost. The cost-volume supply characteristic between public transportation modes in the city is determined on the basis of cost-volume supply curve. Through the comparison between cost-volume supply characteristic of main transportation systems, it is analyzed about the relation between public transportation systems in the city and the characteristic for proper service provision. The application of Bi-modal Tram in the city is concluded that it is effective to reduce the social cost on the existing public transportation system.

• Archives of Plastic Surgery
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• v.33 no.4
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• pp.469-473
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• 2006

Purpose: The transverse rectus abdominis myocutaneous(TRAM) flap has become a reliable method for autogenous breast reconstruction. However, dissection of the tendinous intersections of rectus abdominis is technically difficult. The tendinous intersection has significant vascularity within its fascial layers raising in importance of technique in elevation. If tendinous intersections are damaged during the elevation of the rectus muscle, circulation to TRAM flap can be endangered. The purpose of this study is to evaluate the number of tendinous intersections and to predict anatomical position of the tendinous intersections. Methods: We dissected 182 consecutive TRAM flaps and measured the distance between xiphoid process and each tendinous intersection and evaluated the statistic correlation among the distance, patient's height and position of umbilicus. Results: In this study, in 30.7% of patients, two tendinous intersections were observed in one rectus abdominis muscle, in 67.7% three tendinous intersections, and in 1.6% four tendinous intersections, respectively. But there was no correlation between patient's height and the distance between xiphoid process and each tendinous intersection. Conclusion: It still remains difficult to predict the position of tendinous intersections just by topography before the dissection. Careful and meticulous dissection of the tendinous intersections is still required.

• Journal of the Korean Society for Railway
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• v.10 no.4
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• pp.444-450
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• 2007

The bi-modal tram guided by the magnetic guidance system has two car-bodies and three axles. Each axle of the vehicle has an independent suspension to lower the floor of the car and improve ride quality. The turning radius of the vehicle may increase as a consequence of the long wheel base. Therefore, the vehicle is equipped with the All-Wheel-Steering(AWS) system for safe driving on a curved road. Front and rear axles should be steered in opposite directions, which means a negative mode, to minimize the turning radius. On the other hand, they also should be steered in the same direction, which means a positive mode, for the stopping mode. Moreover, only the front axle is steered for stability of the vehicle upon high-speed driving. In summary, steering angles and directions of the each axle should be changed according to the driving environment and steering mode. This paper proposes an appropriate AWS control algorithm for stable driving of the bi-modal tram. Furthermore, a multi-body model of the vehicle is simulated to verify the suitability of the algorithm. This model can also analyze the different dynamic characteristics between 2WS and AWS.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1799-1804
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• 2009

Bimodal Tram is spotlighted for alternative public transportation system which have punctualness, efficiency, and convenience running between capacity of bus and light rail transit. It have the advantage of automatic operation system when it runs at exclusive right-of-way as like as railway, runs as same as a bus at road concurrently. However, concrete construction plan is not established since the law as well as government subsidy are not defined. For activating bimodal tram construction, this paper analyzed as below. 1) understanding obstacles of activating construction through current status of local governments' bimodal tram promotion plan, 2) finding essential elements for legislation through transportation mode characteristics comparison and system rules analysis, 3) related foreign law analysis.

• Archives of Plastic Surgery
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• v.38 no.4
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• pp.539-542
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• 2011

Purpose: Despite the increasing number of patients with HIV (human immunodeficiency virus) infection, surgical experience with these patients remains limited in aesthetic and reconstructive surgery. The authors performed breast reconsruction with free TRAM (Transverse Rectus Abdominis Muculocutaneous) flap in HIV infected patient firstly in Korea. Methods: A 53-years-old female with HIV positive underwent delayed breast reconstruction with free TRAM flap and 6 months lateral nipple reconstruction was performed. All procedures were performed according to the HIV infection control guidelines provided by the Korea Centers for Disease Control and Prevention. Results: There were no complications such as infection, hematoma and flap loss and symmetry of breast was achieved. Conclusion: When the operation is performed in line with the guidelines of HIV infection control, breast reconstruction with free flap is possible and can obtain successful results.

• Archives of Plastic Surgery
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• v.47 no.1
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• pp.88-91
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• 2020

Cutaneous squamous cell carcinoma (SCC) is the second most common skin malignancy. This report describes the case of an unusual extensive SCC involving the whole hemiface, which required reconstruction with a combination of a dual vascular free transverse rectus abdominis muscle (TRAM) flap and a skin graft. A 79-year-old woman visited our hospital with multiple large ulcerated erythematous patches on her right hemiface, including the parieto-temporal scalp, bulbar and palpebral conjunctiva, cheek, and lip. A preliminary multifocal biopsy was performed in order to determine the resection margin, and the lesion was resected en bloc. Orbital exenteration was also performed. A free TRAM flap was harvested with preserved bilateral pedicles and was anastomosed with a single superior thyroidal vessel. The entire TRAM flap survived. The final pathological examination of the resected specimen confirmed that there was no regional nodal metastasis, perineural invasion, or lymphovascular involvement. The patient was observed for 6 months, and there was no evidence of local recurrence. Usage of a TRAM flap is appropriate for hemifacial reconstruction because the skin of the abdomen matches the color and pliability of the face. Furthermore, we found that the independent attachment of two extra-flap anastomoses to a single recipient vessel can safely result in survival of the flap.

• Archives of Plastic Surgery
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• v.33 no.6
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• pp.737-741
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• 2006

Purpose: This study was to evaluate the expression pattern of CD 18(leukocyte adhesion glycoprotein) in ischemia-reperfusion injury of TRAM flap of rats. Through this study, we can obtain more information about ischemia-reperfusion injury. We want to develop specific medicine to improve the survival rate of TRAM flap in the future. Methods: A TRAM flap supplied by a single pedicle superior epigastric artery and vein was elevated on 60 Sprauge-Dawley rats. The rats were divide into 6 groups (each group n=10); Group O: sham, no ischemia-reperfusion injury, Group I: 2 hour reperfusion after 4 hour ischemia, Group II: 4 hour reperfusion after 4 hour ischemia, Group III: 8 hour reperfusion after 4 hour ischemia, Group IV: 12 hour reperfusion after 4 hour ischemia, and Group V: 24 hour reperfusion after 4 hour ischemia. This study consisted of gross examination for flap survival and flow cytometry study of CD18 on neutrophils. Results: The gross measurement of the flap showed different survival rate in group I(71%), II(68%), III(37%), IV(34%) and V(34%). All experimental groups showed an increase in the expression of CD18 compared to group O. The expression of CD18 was rapidly increased in ascending order in group I, II and III. But, the expression of CD18 was maintained in group IV and V. Conclusion: The results can be implemented in the study to develop drugs which are capable of reducing ischemia-reperfusion injury in microsurgical breast reconstruction.

• Archives of Plastic Surgery
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• v.36 no.6
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• pp.761-766
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• 2009

Purpose: Secondary breast reconstruction is defined as a whole reconstructive procedure to correct complications and to improve the aesthetics when a patient is dissatisfied with her initial reconstruction. We would like to present these particular procedures on previously failed breast reconstruction with analysis of unsatisfactory results. Methods: From June 2002 to August 2008, we performed secondary breast reconstructions for 10 patients with failed breasts. Six patients with implant failure underwent secondary breast reconstructions using free TRAM flaps after the removal of implants. Two patients with partial loss of pedicled TRAM flaps underwent secondary breast reconstruction using Latissimus Dorsi flaps. Two patients with 1 total loss of free TRAM flap and 1 extensive fat necrosis underwent secondary breast reconstruction using implants. Results: The average age of the patients were 36.4 years (26 ~ 47 years). All flaps survived completely and had relatively good aesthetic results in free TRAM cases. There was breast asymmetry in one patient using cohesive gell implants in total loss of previously free TRAM patient, which was corrected by exchanging the implants and placing dermofat grafts. Conclusion: Secondary breast reconstruction differs from primary procedures in several aspects; there are changes in the anatomy and tissue environment of the breasts, and various limitations in choosing reconstruction methods. In addition, the patients may be uncomfortable with previous complication. It is important to consider various factors before deciding to undergo a secondary breast reconstruction carefully with informed consent.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1828-1838
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• 2009

This study will analyze what is favorable of urban structure in order to introduce new transit system like bi-modal tram. As a reasonable transport mode in a city, the bi-modal tram needs to be considered with respect to the space structural pattern and city growth process. The result of this study may provide the basic resource that helps transport decision makers to decide how to introduce bi-modal tram by considering the urban structural characteristics. Also, the results that analyzed a functional characteristic of a bi-modal tram with a effective urban polices will be informative for practical use.