• Journal of the Korean Geotechnical Society
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• v.29 no.1
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• pp.13-22
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• 2013

This paper presents the results of a numerical investigation into the behavior of retaining wall subject to cycles of wetting and drying due to rainfall. The stress-pore pressure coupled finite element modeling strategy was first established for stimulating the wall behavior. A series of finite element analyses were then performed on a range of conditions including different rainfall and backfill conditions. The results indicated that the rainfall intensity was the primary influencing factor for the wall behavior. Also revealed was that the pre-rainfall condition determines the magnitudes and the distribution of matric suction which in fact has a significant impact on the behavior of wall during a major rainfall. This result demonstrates the importance of incorporating the pre-rainfall condition for numerical modeling of walls during heavy rainfall. Practical implications of the findings from this study are discussed in great detail.

• Journal of Chest Surgery
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• v.35 no.10
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• pp.750-754
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• 2002

Primary cardiac tumors are rare and about 20~25% of primary cardiac tumors are malignant. Moreover, primary malignant mesenchymoma of the heart is extremely rare. Recently, we have experienced two cases of cardiac malignant mesenchymoma. In the first case, malignant mesenchymoma which was originated from the posterior wall of the left atrium obstructing the mitral orifice was revealed pathologically in a 61-year-old woman with mitral regurgitation. The mass, which was 2.7$\times$3.7cm in size on the posterior wall of left atrium, was extended to the posteromedial commissure and annulus of the mitral valve. The mass was resected partially without excision of the left atrial free wall. She was discharged after 30 days without any problems and she received chemotherapy and followed up for 19months. The second case was a 4$\times$5cm in size, friable, yellow-whitish multilobulated mass in the left atrium which was originated from the left lower pulmonary vein. Multiple minor tumor nodules were found in the wall of the left atrium and the posterior leaflet of mitral valve. Partial mass excision and mitral valve replacement were performed.

• Journal of Chest Surgery
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• v.8 no.2
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• pp.159-168
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• 1975

We have experienced 61 cases of Clinically diagnosed tuberculous peripleural abscess which was surgically treated at St. Mary's Hospital of Catholic Medical College from Mar. 1963 to Feb. 1974. Out of them, 52 cases of pathologically confirmed tuberculous peripleural abscess were reviewed and its pathogenesis, treatment and so called "rib caries" were discussed. In the past, they have been described as a variety of the names, such as rib caries, cold abscess of the chest wall, pericostal abscess, lymphadenitis tuberculosa of the chest wall, chronic draining sinuses of the chest wall and other descriptive terms. Although it has been said that the tuberculous abscess on the chest wall developed as a secondary disease from so called "rib caries" but now it has been clear that this abscess occurred not from tuberculosis of the rib but from tuberculous lesion developed between end-othoracic fascia and parietal pleura usually following pulmonary tuberculosis and/or tuberculous pleurisy and the involvement of rib or ribs are secondary one from peripleural abscess, as we confirmed. Therefore we advocate that the nomination, rib caries, should not be used unless there is a primary tuberculous lesion on ribs. The results were as follows: 1. The highest age group of tuberculous peripleural abscess was ranged from the first to third decade (78%) 2. The location of tuberculous peripleural abscess on the chest wall were as follows, 31 cases on the anterior, 19 cases on lateral and 2 cases on the posterior. 3. On x-ray examination, abnormal findings including parenchymal tuberculous lesion and pleural changes were seen is 38 cases. 4. There was no destructive change of periosteum and rib in 23 cases of tuberculous peripleural abseess during operation. However the periosteal denudation and/or rib destruction were found in 29 cases. 5. The all cases of tuberculous peri pleural abscess developed from between endothoraclc fascia and parietal pleura, as we confirmed. With antituberculous therapy, operation should be radical by wide incision on the lesion including thorough curettage with proper drainage of Iiquified caseating materials and appropriate rib resection, if necessary.tion, if necessary.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.237.1-237.1
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• 2010

Recent developments such as concern over global warming, depletion of fossil fuels and increase in energy demands by the increasing world population has eventually lead to mass production of electricity using renewable sources. Ocean contains energy in form of thermal energy and mechanical energy: thermal energy from solar radiation and mechanical energy from the waves and tides. The current paper looks at generating power using waves. The primary objective of the present study is to maximize the primary energy conversion (first stage conversion) of the base model by making some design changes. The model entire consisted of a numerical wave tank and the turbine section. The turbine section had three components; front guide nozzle, augmentation channel and the rear chamber. The augmentation channel further consisted of a front nozzle, rear nozzle and an internal fluid region representing the turbine housing. Different front guide nozzle configuration and rear chamber design were studied. As mentioned, a numerical wave tank was utilized to generate waves of desired properties and later the turbine section was integrated. The waves in the numerical wave tank were generated by a piston type wave maker which was located at the wave tank inlet. The inlet which was modeled as a plate wall which moved sinusoidally with the general function, $x=asin{\omega}t$. In addition to primary energy conversion, observation of flow characteristics, pressure and the velocity in the augmentation channel, rear chamber as well as the front guide nozzle are presented in the paper. The analysis was performed using the commercial code of the ANSYS-CFX. The base model recorded water power of 29.9 W. After making the changes, the best model obtained water power of 37.1 W which represents an increase of approximately 24% in water power and primary energy conversion.

• Journal of Chest Surgery
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• v.46 no.2
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• pp.159-161
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• 2013

Synovial sarcoma is a malignant soft tissue tumor that most commonly occurs in the extremities of young and middle-aged adults, in the vicinity of large joints. Although synovial sarcoma is frequently associated with joints, it may arise in unexpected sites, such as the mediastinum, heart, lung, pleura, or chest wall. Primary synovial sarcoma of the pleura is rare. To date, nearly 36 cases of primary synovial sarcoma of the pleura have been reported since Gaertner et al. published the first case in 1996. The oncologic characteristics, treatment, and prognosis for pleural synovial sarcomas are not well defined because of a paucity of data. However, a multimodal approach, including surgical resection, chemotherapy, and radiotherapy, has generally been suggested. We report the outcome of one patient with primary pleural synovial sarcoma treated with radical resection and adjuvant treatment.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.3
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• pp.217-225
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• 2008

A new micro reformer system consisted of a micro reformer, a microcombustor and a micro evaporator was studied experimentally and computationally. In order to satisfy the primary requirements for designing the microcombustor integrated with a micro evaporator, i.e. stable burning in a small confinement and maximum heat transfer through a wall, the present microcombustor is simply cylindrical to be easily fabricated but two-staged (expanding downstream) to feasibly control ignition and stable burning. Results show that the aspect ratio and wall thickness of the microcombustor substantially affect ignition and thermal characteristics. For the optimized design conditions, a premixed microflame was easily ignited in the expanded second stage combustor, moved into the smaller first stage combustor, and finally stabilized therein. A micro reformer system integrated with a modified microcombustor based on the optimized design condition was fabricated. For a typical operating condition, the designed micro reformer system produced 22.3 sccm hydrogen (3.61 W in LHV) in an overall efficiency of 12%.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.353-356
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• 2010

A computational study on the enhancement of parallel supersonic-subsonic mixing wakes is conducted and compared with available experimental data. The first aim of the present work is to show a direct comparison between numerical predictions and equivalent experimental data for the baseline case. The Pitot pressure distribution data are in good agreement between computation and experiment, and the results show that Menter's SST model with the compressibility correction gives the best performance. Further we investigate the effects of primary parameters such as the position of the cavity, and the arrangement of the cavity at the given flow condition.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.466-471
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• 2004

In gas turbines, excess air for combustion is available and therefore lean premixed combustion is the most promising approach to the significant reduction of thermal NOx emissions. At lean conditions, however, flame stability is inherently worse and hence combustion tends to be incomplete. Efforts have been devoted toward extending the operating range of complete combustion at leaner conditions. One of them is the lean-lean two-stage combustion where lean to ultra-lean secondary mixtures are mixed with the hot burned gas from the primary stage. Conventional flame combustion or flameless reaction are initiated depending on the conditions of the secondary zone. In the first part of the present study, the effects of fuel injection on the emissions and flame stability were investigated for a single tubular flame, In the second part, the emissions and flame stability were studied for a two-stage combustor with secondary mixture injected through the tangential slots on a cylindrical combustor wall. The effects of the ratio of air flow rates to the primary and secondary zones on the emissions and combustion characteristics were investigate.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2008.05a
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• pp.155-158
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• 2008

Today, apartment is the primary housing type in Korea. In the past, there were many apartment floor plans in the same design way. There have been changes to complex and luxury plans in these days because people want to fit their own needs and wants to the plans. The primary purpose of this study is to analyze interior design trend of medium-large size apartment after year 2000. For that, this study used 7 different construction companies, 13 apartment complexes and 30 unit plan cases which were on sale from April 2007 to April 2008 in Seoul and the Metropolitan area. The results of analysis are as follows: First, most cases had 4LDK and 2bathroom with a dress-room. Second, characteristics of the interior design showed that the variety finish materials used in the units. For wall finish materials, wallpapers were used in mostly regardless in different areas. For floor finish materials, stone and tile were used in similar ratio in the entrance area whereas wood floor mostly was used in living room and kitchen areas. This study shows some significant characteristics of today's apartment even it has some limitations because of small amount of survey cases. More detailed and deeper study will be done continuously.

• Imaging Science in Dentistry
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• v.32 no.3
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• pp.181-185
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• 2002

The melanotic neuroectodermal tumor of infancy is a rare neoplasm arising in the first year of life. A 33-day-old female infant had an enlarged alveolar ridge on the right anterior maxilla. Intraoral examination revealed a nonulcerative swelling at the site. An intraoral radiograph showed an ill-defined radiolucency on the right anterior maxilla and displacement of primary incisors from their alveolar sockets. CT scans revealed an expansion of the surrounding bone and partial destruction of the anterior wall of the premaxilla. Histopathologic examination showed the cytoplasm of neuroblastic cells and eosinophilic, epithelioid cells frequently contained a dark brown granular pigment that stained positively to vimentin and HMB45, focally positive to NSE and cytokeratin. Four weeks after the operation, CT scans showed a rapidly growing soft tissue mass occupying right maxillary sinus encroaching to the orbit and nasal cavity. The final diagnosis was made as a malignant melanotic neuroectodermal tumor of infancy.