• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.1
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• pp.18-30
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• 1999

A heat transfer analysis for the two-dimensional (2-D) steady state using finite difference method (FDM) is performed to predict the thermal behavior of the primary first-wall (FW) system of fusion reactor under various geometric and thermo-hydraulic conditions, such as the beryllium (Be) armor thickness, pitch of cooling tube, and coolant velocity. The FW consists of authentic steel (type 316 stainless steel solution annealed) for cooling tubes, Cu for cooling tubes embedding material, and Be for a protective armor, based on the International Thermonuclear Experiment Reactor (ITER) report. The present 2-D analysis, the control volume discretized with hybrid grid (rectangular grid and polar grid) and Gauss-Seidel iteration method are adapted to solve the governing equations. In the present study, geometric and thermo-hydraulic parameters are optimized with consideration of several limitations. Consequently, it is suggested that the adequate pitch of cooling tube is 22-32mm, the beryllium armor thickness is 10-12mm, and that the coolant velocity is 4.5m/s-6m/s for $100^{\circ}C$ of inlet coolant temperature. The cooling tube should locate near beryllium armor. But, it would be better for locating the center of Cu wall, considering problems of material and manufacturing. Also, 2-D analysis neglecting the axial temperature distribution of cooling tube is appropriate, regarding the discretization error in axial direction.

• Journal of Chest Surgery
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• v.11 no.4
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• pp.451-455
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• 1978

Rhabdomyosarcoma is relatively rare in general pediatric population. Furthermore, the primary site in the thorax is one of the least sites. Because most patient, when first seen, are extensively advanced and bad in prognosis, an adequate work-up prior to any definitive therapy must be undertaken. Author experienced 2 cases of embryonal rhabdomyosarcoma originating from chest wall. Both 2 cases are included in Group III [Rhabdomyosarcoma-Intergroup Protocol Grouping], one case is treated with radical surgery and radiation therapy, and the other case is treated with radiation therapy and chemotherapy. So author present 2 cases of embryonal rhabdomyosarcoma with reference.

• Clinical and Experimental Pediatrics
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• v.51 no.1
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• pp.98-101
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• 2008

Leiomyosarcoma is an uncommon soft tissue sarcoma of mesenchymal cell origin, which shows smooth muscle differentiation. Leiomyosarcoma is seldom found in the pediatric population, and accounts for fewer than 2% of all soft tissue sarcomas. Leiomyosarcoma of the chest wall is extremely rare in children. We report here a case of an 8-year-old boy with a primary leiomyosarcoma that was incidentally found as a rib mass. The patient underwent a complete resection for a suspected osteochondroma diagnosed by a three-dimensional chest computed tomography examination. Pathological findings of the mass revealed intersecting fascicles of spindle cells showing cigar-shaped nuclei, inconspicuous nuclear pleomorphism and occasional mitotic figures in the background of a suspected osteochondroma of the rib. This report documents the first description of a leiomyosarcoma possibly arising in an osteochondroma of the rib in a child.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.617-621
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• 2003

The purpose of this paper is to analyze piping failure trend of safety pipings In domestic nuclear power plants. First, database for the piping failure was constructed with 105 data fields. The database includes plant population data, event data, and service history data. 7 kinds of piping failures in domestic NPPs were investigated. Among the 7 cases, detailed root causes were investigated for 3 cases. The first one is pipe wall thinning in main feedwater pipings of Westinghouse 3 loop type plants. The root cause of the wall thinning was flow accelerated corrosion near welding area. The next one is leak event in chemical and volume control system(CVCS) due to vibration. Some cracks occurred in socket welding area. The events showed that the integrity or socket weld is very vulnerable to vibration. The last one is also a leak event in primary sampling line in Korean standard reactor due to thermal fatigue. Although the structural integrity was not maintained by the events, there was no effect on nuclear safety in the above 3 piping failure eases.

• Tuberculosis and Respiratory Diseases
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• v.46 no.2
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• pp.273-280
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• 1999

This is a report of gastric metastases secondary from a primary small cell carcinoma of the lung in two men. Blood-borne metastatic involvement of the stomach by cancer is a rare entity. According to the reports in the literature the prevalence of metastasis to the stomach occurs in 0.4% and the most common cell type of the primary lung carcinoma is large cell type(3.7%) followed by adenocarcinoma(2.4%), small cell carcinoma(1.7%) and squamous cell carcinoma(0.7%). The most common tumors that spread to the stomach through the blood stream are malignant melanoma, breast carcinoma and lung carcinoma. Most of the gastrointestinal tract metastases had no specific symptoms because of its submucosal involvement. The prognosis was poor and the mean survival period from the onset of symptoms was 49 days. The first patient was a 56-year-old man who had primary lung carcinoma with brain metastasis. Gastroscopic findings showed two elevated mass lesions in the anterior wall of the mid body with central ulcer and the posterior wall of the fundus with intact surface mucosa. Pathologic examination of stomach tissue revealed small cell type tumor cells infiltrate in the stomach wall segmentally without destruction of the glands. The second patient was a 67-year-old man who had no other evidence of the distant metastasis. Gastroscopic findings showed a huge, oval shaped, ulcerofungating mass with deep penetrating central ulcer coated with dirty exudate in the anterior wall from mid to upper body of the stomach, and thickened elevated rugal folds in the posterior wall of the fundus. Pathologic examination of stomach tissues revealed the small cell type tumor cells showing small smudged nucleus infiltrate into the mucosa of the stomach and the architecture of mucosa intact. We report the two cases of metastatic gastric cancer from the primary small cell lung carcinoma with the literature review.

• Geotechnical Engineering
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• v.4 no.1
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• pp.7-16
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• 1988

The safety factor has been used widely and uniquely at present to check the safety of the structure . However, probability of failure would be logically attempted to check the reliability of the structure in future Coulomb's theory or Rankine's theory has been applied in practice to retaining earth structure in spite of the fact that the lateral earth pressure, which is the primary factor in the determination of wall structure, depends on the modes of wall movement . This study is concentrated on the two modes of , wall movement (active case rotation about bottom(AB) , active case rotation about top(AT)) of the overturning'failure of vertical wall with horizontal sand backfill . The static active earth pressure is determined by applying each of Coulomb's theory, Dubrova's redistribution theory and Chang's method The earthquake active earth pressure is determined by adding Seed and Whitman's earthquake pressure to the static earth pressure , On the condition that design variables are fixed with each of the above earth pressure, reliability is analyzed using the recently developed method of AFOSM (Advanced First Order Second Moment)

• Journal of Plant Biology
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• v.35 no.3
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• pp.211-217
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• 1992

In order to elucidate the formation of reaction tissues during the transition from primary to secondary growth, the developmental anatomy was conducted in the first internode of Acer sacchan'num seedling in horizontal position. During the transition from primary to secondary growth, tension wood(gelatinous fiber) was gradually developed on the upper side only, And the tension wood formation in the upper side of the horizontal first internode proceeds acropetally from base to apical portion. Some of the anatomical features of tension wood start to be in the primary vascular tissue and a typical tension wood show during the secondary growth, Therefore, the procambium seems to respond to the gravity as well as vascular cambium. For this reason, both procambium and vascular cambium has to regard as the same meristem, On the other hand, the upper side vessels were longer than those of the lower side in the horizontal first internode. The lateral-wall pitting of vessel elements, however, showed no differences between upper and lower sides which have alternate type. The width and height of rayon the upper side of horizontal first internode was larger as compared with the lower side.r side.

• Journal of the Korean Geotechnical Society
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• v.29 no.1
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• pp.81-92
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• 2013

This paper presents the results of a numerical investigation into the behavior of retaining wall subject to cycles of freezing and thawing due to seasonal temperature change. The thermo-hydro-mechanical coupled finite element modeling strategy was first established to simulate the wall behavior. A series of finite element analyses were then performed on a range of conditions representing seasonal temperature change characteristics. The results indicated that the average freezing temperature and the number of cycles of freezing and thawing were the primary influencing factors for the wall behavior. Also revealed was that the duration of freezing period does not significantly affect the wall displacement and the lateral earth pressure, and that the earth pressure on the wall does not significantly change due to the freezing and thawing action suggesting that the increase in the wall displacement during the freezing and thawing action may be attributed to degradation of backfill due to the freezing and thawing action.

• Journal of Trauma and Injury
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• v.25 no.4
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• pp.172-177
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• 2012

Purpose: After damage control surgery, abdominal wall closure may be impossible due to increased intra-abdominal pressure (IAP), and primary closure may induce abdominal compartment syndrome. The purpose of this study was to investigate changes in the IAP and the feasibility of abdominal wall closure using artificial mesh. Methods: From July 2010 to July 2011, 8 patients with intra-abdominal hypertension underwent abdominal wall closure using artificial mesh. Medical data such as demographics, diagnosis, operation, IAP, postoperative complications, mortality and length of hospital stays were collected and reviewed, retrospectively. One patient was excluded because of inadequate measurement of the IAP. Results: Seven patients, 4 males and 3 females, were enrolled, and the mean age was 54.1 years old. Causes of operations were six traumatic abdominal injuries and one intra-abdominal infection. The IAP was reduced from $21.9{\pm}6.6mmHg$ before opening the abdomen to $15.1{\pm}7.1mmHg$ after fascial closure. Fascial closure was done on $14.9{\pm}17.5$ days after the first operation. The mean lengths of the hospital and the intensive care unit (ICU) stays were 49.6 days and 29.7 days respectively. Operations were performed $3.1{\pm}1.5$ times in all patients. Two patients expired, and one was transferred in a moribund state. Three patients suffered from complications, such as retroperitoneal abscesses, enterocutaneous fistulas, and bleeding that was related to the negative pressure wound therapy. Conclusion: After abdominal wall closure using artificial mesh, intra-abdominal pressure was well controlled, and abdominal compartment syndrome does not occur. When the abdominal wall in patients who have intra-abdominal hypertension is closed, artificial mesh may be useful for maintaining a lower abdominal pressure. However, when negative pressure wound therapy is used, the possibility of serious complications must be kept in mind.

• Applied Microscopy
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• v.23 no.1
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• pp.91-108
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• 1993

The relationship of cartilage canals to initial osteogenesis of primary ossification center of developing vertebrae in human fetuses ranging from 50mm to 260mm in crown rump length was studied by light and electron microscopy. The cartiage canals of the thoracic vertebrae were first observed at 60mm fetus. Cartilage canals were identified as vascular channels arising from perichondrium surfaces. A number of cartilage canals were observed around the primary center of ossification at 80mm fetus. At 120mm fetus, cartilage canals of the bodies of vertebra were increased. Eventually the canals were eroded from the main medullary cavity and remained at only peripheral regions of growth cartilage. Superficial, intermediate, and deep canals were identified by the characteristics of cartilage cells. Fibroblasts, undifferentiated mesenchymal cells, and vacuolated macrophages were observed adjacent to the matrix of resting cartilage cells in the superficial canal. Fibroblasts and mesenchymal cells were densely packed at the tip of canal, giving an epithelial appearance to the clustered cell in the intermediate canal. Vacuolated macrophages were in contact with matrix of hypertrophied cartilage. The thick-walled vessels in the intermediate and deep canals consisted of typical endothelial cells, but in the newly formed vessels contained mesenchymal cells and fibroblasts incorporated into the vessel wall. During lengthening of cartilage canal, the matrix of cartilage cells were invaded by newly formed capillaries and vacuolated macrophages. At the deep canal, the lateral wall of the canal terminated in matrix containing calcified cartilage. The mesenchymal cells began to differentiate into osteoblasts adjacent to the calcified matrix. The results indicate that the connective tissue cells within the cartilage canals proliferate and differentiate into osteoblasts at the site of primary ossification center.