• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.113-117
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• 2006

This paper Is for development of cooling module in order to maintain heat and water balance in fuel cell vehicle. Thermal management system for fuel cell is disadvantage because the temperature of coolant is lower than that of ICE and heat duty of radiator is higher. By CFD simulation, cool ing module was developed for water balance of system. Hot chamber test and hot area/high altitude test on cool ing module was completed.

• 대한두경부종양학회지
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• 제27권2호
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• pp.240-242
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• 2011

Branchiogenic carcinoma is extremely rare and is defined as a malignant degeneration within the confines of epithelial remnants derived from the embryonal branchial apparatus. Two major diagnostic criteria are histologic proof of transitional area from normal cyst epithelium to invasive squamous cell carcinoma and absence of an identifiable primary carcinoma elsewhere. A 62-year old woman visited our department complaining of a non-tender, movable mass in left upper lateral neck. After a complete mass excision, histopathologic diagnosis of the surgical specimen was branchiogenic squamous cell carcinoma. I report a case of branchiogenic carcinoma with literature review.

• 대한두경부종양학회지
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• 제29권1호
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• pp.14-17
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• 2013

Giant cell reparative granuloma(GCRG) is a non-neoplastic rapidly expanding and locally destructive tumor that occurs almost exclusively within the mandible and maxilla. A 58-year-old man, complained of a mass on the left infra-auricular area starting 2 months ago. The radiologic finding suggests a mass that originate from mandible, pathology diagnosed the lesion as a giant cell reparative granuloma. The tumor was surgically excised without complications. We report the case with a review of literature.

• Journal of Korean Neurosurgical Society
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• 제37권6호
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• pp.462-465
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• 2005

We report a case of a 67-year-old woman with giant cell tumor of the temporal bone. A 67-year-old woman presented with localized tenderness, swelling, sensory dysesthesia, dizziness, and headache over the left temporal bone. She was neurologically intact except left hearing impairment, with a nonmobile, tender, palpable mass over the left temporal area. A brain computed tomography(CT) scans showed a relatively well defined heterogenous soft tissue mass with multiple intratumoral cyst and radiolucent, osteolytic lesions involving the left temporal bone. The patient underwent a left frontotemporal craniotomy and zygoma osteotomy with total mass removal. Permanent histopathologic sections revealed a giant cell tumor. She remains well clinically and without tumor recurrence at 2 years after total resection.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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• pp.249-252
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• 1997

Electroluminescence(EL) devices based on organic thin layers have attracted lot of interests because of their possible application as large-area display-emitting display. One of the problems of such devices is lifetime of the cell, where the degradation of the cell is partially due to the crystalliyzation of organic layers. In large part, this problem can be solved by using a multilayer device structure prepared by vapor deposition technique. In this study, blue light-emitting multilayer organic electroluminescence devices were fabricated vsing Poly (9-vinylcarbaEole) (PVK) and 2- (4-tert-butylphenyl)-5-(4$^{#}$-bis-phenyl) 1,3,4-oxadiazole (PBO) as hole trasport and electron transport material, respectively, where trim(8-hyd roxyquinolinate) aluminum (Al $q_3$) was used as a luminescenct material. A cell structure of glass sub- strate/indume-tin-oxide(ITO)/PCK/Al $q_3$/PBD/Mg:In was employed. Blue emission peak at 510nm was observed with this cell structure.e.

• 한국통신학회논문지
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• 제21권12호
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• pp.3154-3164
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• 1996

A major concern in a cellular mobile communication system is how to efficiently utilize the limited amount of frequencies. Various channel assignment methods and traffic sharing schemes have been proposed to improve system performance. However, these approaches suffer from complicated software and hardware requirements due to increased amount of traffic control In this paper, we propose a new method for improving system performance by controlling the powers of the set-up and voice channels of each cell site. We first show that the average number of blocked calls in a system is minimized when the traffic reates are made identical for all cell sites in a system. This result, together with the relationship between the channel powers and the service area, is used to determine the appropriate channel powers of each cell site. We also determine the upper limit on the channel power of each cell site considering co-channel interference and numerically show that the proposed method is effective in reducing the number of blocked calls without an excessive increase in the amount of system control.

• 한국수소및신에너지학회논문집
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• 제19권6호
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• pp.467-473
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• 2008

This study is to investigate the influence of catalyst loading quantity on the direct methanol fuel cell (DMFC) performance. In this paper, Pt-Ru and Pt-black loading as the catalyst were varied from 1 to $4mg/cm^2$ at the anode and cathode, respectively. The experiment was conducted with single fuel cell consisted of $5cm^2$ effective electrode area, serpentine type flow pattern and Nafion 117 membrane. Also, AC impedance and methanol crossover current were measured to investigate the performance loss precisely. As a result, the performance of fuel cell was significantly increased with the increase of cathode catalyst loading. However, the performance did not increase further above a certain Pt-Ru catalyst loading as the increase of anode catalyst loading.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.264-269
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• 2000

As a part of the ongoing effort towards commercial application of high-temperature fuel cell power generation systems, we have recently built a pilot-scale molten carbonate fuel cell power plant and tested it. The stack test system is composed of diverse peripheral units such as reformer, pre-heater, water purifier, electrical loader, gas supplier, and recycling systems. The stack itself was made of 40cells of $6000cm^2$ area each. The stack showed an output higher than 25kW power and a reliable performance at atmospheric operation. A pressurized performance was also tested, and it turned out the cell performance increased though a few cells have shown a symptom of gas crossover. The pressurized operation characteristics could be analyzed with numerical computation results of a stack model.

• 대한두경부종양학회지
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• 제25권2호
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• pp.156-159
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• 2009

Squamous cell carcinoma, which is a common primary head and neck malignant neoplasm that is usually restricted to the mucosal surfaces of the upper aerodigestive tract and skin, is very unusual in the major salivary gland. Among them, few cases are regarded as primary carcinomas. In this article, we present two cases of squamous cell carcinoma in the parotid gland, who first presented with painful mass on infraauricular area.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.33-36
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• 2008

Cell degradation when anode channels are blocked during cold start up was tested and measured. Proton exchange membrane fuel cell (PEMFC) stacks with several configurations of channel blockages were operated and decay in performance was analyzed. When only channels near hydrogen inlet were blocked, performance was rarely changed. In contrast, significant cell reversal occurred and considerable amount of $CO_2$ was produced when all channels near inlet and outlet were blocked. In the case, it was also observed that performance was severely decreased in the area where hydrogen was not supplied sufficiently.