• Journal of Korean Society for Geospatial Information Science
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• v.16 no.1
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• pp.83-93
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• 2008

The topographic effect is one of the most important component in the solution of the geodetic boundary value problem (geodetic BVP). Therefore, topographic effect should be considered properly for developing the precise geoid model, especially for the area where contains many mountains like Korea. The selection of gravity reduction method in the context of the precise geoid determination depends on the magnitude of its indirect effect, the smoothness and magnitude of the reduced gravity anomalies, and their related geophysical interpretation. In this study, Korean digital elevation model with 100m resolution was constructed and topographic effect was calculated by three reduction methods as like Helmert condensation method and RTM method and Airy-isostatic reduction method. Through the analysis of computation results, we can find that RTM reduction method is the best optimal method and the results shows that gravity anomaly and indirect effect of geoidal height are $0.660{\pm}13.009mGal$, $-0.004{\pm}0.131m$ respectively and it is the most gentle slow of the three methods. Through this study, it was found that the RTM method is better suitable for calculating topographic effect precisely in context of precise geoid determination in Korea than other reduction methods.

• Tuberculosis and Respiratory Diseases
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• v.43 no.5
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• pp.805-811
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• 1996

Congenital cystic adenomatoid malformation of the Lung(CCAM) is characterized by anomalous fetal development of terminal respiratory structures, resulting in an adenomatoid proliferation of bronchiolar elements and cystic formation. CCAM was first described and differentiated from other cystic lung disease in the English literature by Ch'in and Tang in 1949. CCAN is a rare, potentially lethal form of congenital pulmonary cystic disease and the salient features of lesion are an irregular network of terminal respiratory bronchiole-like structures and macrocysts variably lined by pseudostratified ciliated columnar epithelium and simple cuboidal epithelium. Adult presentation of CCAM of the lung is so rare that only 9 cases have been reported in the literature of date. The pathogenesis of CCAM remains disputed and reseachers have variously proposed that the lesion represents a developmental anomaly, hamartoma, or a fonn of pulmonary dysplasia. Van Dijk and Wagenvoort divided CCAM into three subtypes : cystic, intermediated, and solid. These correspond to types I, II, and III of Stocker. In adults, the evaluation of cystic or multi cystic lung disease requires consideration of a differential diagnosis including the acquired lesions of lung abscess, cavitary neoplasm or inflammatory mass, bullous disease, bronchiectasis, and postionflammatory pneumatocele. Congenital lesions such as sequestration, bronchopulmonary-foregut anomalies, and bronchogenic cyst are also encounted. The definitive treatment for CCAM is complele removal of the involved lobe. Panial lobectomy leads to multiple complications, including severe post-operative infection. We report a case of CCAM in a 14-year-old female presentated with a pneumothorax and large bullae, who was treated by surgical remove of the involved lobe.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.4
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• pp.343-352
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• 2019

Abnormal orofacial functions such as lip incompetency in the period of growth and development can cause morphological anomalies of the craniofacial complex. Therefore, it is crucial to make an early diagnosis based on the evaluation of the myofunctional conditions, and to make appropriate treatment plans. The objectives of this study were to quantitatively evaluate the standard lip closing force (LCF) of each age in the elementary school children, and to evaluate the relationships between LCF and affecting factors. The sample consisted of 765 children who were 7 - 12 years old in Jeonju city. Clinical examination about occlusal conditions and lip competency, and LCF measurement were performed by a single examiner. LCF was measured three times for each children with the LCF measuring device. The LCF was correlated positively with age in both sexes. The distribution of LCF groups was correlated significantly with Angle's classes and lip competency (p = 0.016, 0.004). The proportion of children with high LCFs was greater in the "competent lip" group, whereas the proportion of those with low LCFs was greater in the "incompetent lip" group.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.6
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• pp.699-710
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• 2009

If a country has her geoid model, it could be determine accurate orthometric height because the geoid model could provide continuous equi-gravity potential surface. And it is possible to improve the coordinates accuracy of national control points through geodetic network adjustment considering geoidal heights. This study aims to find the best way to develop geoid model in Philippines which have similar topographic conditions as like Malaysia and Indonesia in Eastsouth asia. So, in this study, it is surveyed the general theories of geoid determination and development cases of geoid model in Asia and it is computed that the geoidal heights and gravity anomalies by spherical harmonic analysis using EGM2008, the latest earth geopotential model. The results show that first, the development of gravimetric geoid model based on airborne gravimetry is needed and second, about 200 GPS surveying data at national benchmark is needed. It is concluded that it is the most reasonable way to develop the hybrid geoid model through fitting geometric geoid by GPS/leveling data to gravimetric geoid. Also, it is proposed that four band spherical Fast fourier transformation(FFT) method for evaluation of Stokes integration and remove and restore technique using EGM2008 and SRTM for calculation of gravimetric geoid model and least square collocation algorithm for calculation of hybrid geoid model.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.2 no.2
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• pp.178-184
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• 1999

Purpose: The aims of this study were to evaluate the clinical manifestations and prognosis of the syndromic and nonsyndromic intrahepatic bile duct paucity (IHBDP). Methods: We studied histology of 42 infants with neonatal cholestasis. Fourteen patients were diagnosed as IHBDP. We evaluated the clinical manifestations, courses and prognosis retrospectively. Results: Underlying disease of the 42 infants with neonatal cholestasis were biliary atresia in 23, intrahepatic bile duct paucity in 14 (Alagille syndrome in 4 and nonsyndromic IHBDP in 10), neonatal hepatitis in 5 infants. The mean ratio of the bile ducts per portal tract was 0.087 (range: 0~0.5). The manifestations in 4 patients with Alagille syndrome demonstrated as follows: characteristic face in 3, chronic cholestasis in 4, posterior embryotoxon in 2, vertebral anomalies in 2, peripheral pulmonary stenosis in 2. One of 4 patients of Alagille syndrome improved cholestasis and the other 3 patients were remained their cholestasis and growth retardation. All patients of the nonsyndromic IHBDP were idiopathic. Seven out of 8 patients of nonsyndromic IHBDP showed improvement of cholestasis, and one patient received liver transplantation due to cirrhosis. Conclusion: This study suggested that IHBDP should be considered in the differential diagnosis of neonatal cholestasis. The outcome of idiopathic IHBDP was better than predicted.

• Clinical and Experimental Pediatrics
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• v.46 no.2
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• pp.154-161
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• 2003

Purpose : The prognosis of patients with corrected transposition of the great arteries(C-TGA) is variably affected by associated intracardiac defects, systemic right ventricular function, tricuspid valve competence, and conduction disturbances. This study aims to evaluate the importance of those factors at mid-term follow-up. Methods : Medical records of 94 patients(males 58, females 36; mean age at last follow-up, $12{\pm}9$ years; mean follow-up duration, $9{\pm}6.4$ years) diagnosed between January 1980 and May 2002 at Seoul National University Children's Hospital were studied retrospectively. Results : Among 94 patients, operations were performed in 72 patients(classic operations in 55; double switch operations in 17). Among prognostic factors including associated intracardiac anomalies(at least moderately severe tricuspid insufficiency(TI), ventricular septal defect, pulmonary stenosis and pulmonary atresia), intracardiac operation and complete atrioventricular block, TI was the only significant factor for death(P=0.001), and in turn, Ebstein anomaly and high grade atrioventricular block predicted TI. 20-year survival without TI was 77%, but only 35% with TI(P=0.0002); excluding perioperative death, the 20-year survival rates with and without TI were 48% and 87% respectively(P=0.008). There was no statistical difference in 20-year survival rate or association with TI between classic and double switch operation. Conclusion : TI was the major prognostic factor for C-TGA and was associated with Ebstein anomaly and high grade atrioventricular block at mid-term follow-up. Long-term follow-up is required to evaluate other factors, including double switch operations and associated intracardiac defects more exactly.

• Journal of Chest Surgery
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• v.36 no.3
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• pp.136-141
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• 2003

We assessed the intermediate-term result of tricuspid annuloplasty (TAP) for tricuspid valve regurgitation (TR) associated with congenital heart disease in adults. Risk factors for residual TR were also analysed. Material and Method: From August 1989 to June 2001, seventy three adult patients, 51 females and 22 males, underwent TAP for TR associated with various congenital heart disease. Their age ranged from 46 years to 73 years (mean:43). Associated heart anomalies were atrial septal defect (55), ventricular septal defect (6), partial anomalous pulmonary venous return (4) and others (8). Preoperative and post-operative TR velocities were 3.25 m/sec and 2.56 m/sec respectively, and the types of TAP were De Vega in 43, Kay in 18 and Ring annuloplasty in 12. Postoperative follow-up duration was 2,347 patient-month (mean: 32.6 months), and 134 two-dimensional echocardiographic examinations were done during this period. Residual TR greater than III/IV was considered as TAP failure. Result: TAP failure was observed in 7 patients (9.6%), and one patient among them underwent tricuspid valve replacement. Risk factors for TAP failure were diagnosis other than atrial septal defect (p=0.001), preoperative (p=0.038) and postoperative (p=0.028) high TR velocity. There was no statistical significance in terms of TAP methods. Conclusion: Careful evaluation of valve morphology and aggressive surgical intervention are mandatory for the repair of TR with preoperative or residual RV pressure overload.

• Clinical and Experimental Pediatrics
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• v.45 no.10
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• pp.1213-1218
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• 2002

Purpose : Hydronephrosis constitutes a great portion of fetal anomalies screened by prenatal sonogram. The present authors made an attempt to access its natural courses through follow up neonatal hydronephrosis diagnosed by prenatal sonogram. Methods : The study was composed of 23 neonates(36 renal units) who were diagnosed with hydronephrosis through prenatal sonogram screening and confirmed 3-7 days after birth with sonographic evaluation at Kyung Hee University Hospital. The neonates were closely monitored for 12-24 months with renal sonogram, diuretic renogram, intravenous pyelography(IVP) and voiding cystoureterography(VCUG). Results : The underlying diseases were composed of 16 cases(44%) of functional abnormalities, 14 cases(39%) of ureteropelvic junction(UPJ) obstruction, three cases(8%) of vesicoureteral reflux (VUR) and on case each of multicystic dysplastic kidney, UPJ obstruction with ureteral stenosis and ureterovesical junction(UVJ) obstruction with VUR. The degree of hydronephrosis was divided into three classes according to its severity. In 30 renal units with UPJ obstruction and functional abnormalities, 26(87%) showed mild hydronephrosis, while four(13%) were moderate. During the follow up period, six cases(20%) showed natural resolution of hydronephrosis, 15 cases(50%) showed improvement while two cases(7%) were aggravated with improvement only after surgery of the underlying disease. The cases which showed natural resolution were all mild hydronephrosis at diagnosis and the cases which underwent surgery due to continuous aggravation were mild one case and moderate one case. Conclusion : Those with cases of mild hydronephrosis show rapid natural improvement. On the other hand, in some cases, follow up monitoring reveal aggravation of the situation, emphasizing the necessity for thorough follow up for a long period of time.

• Journal of the Korean earth science society
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• v.43 no.1
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• pp.128-139
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• 2022

This study aimed to investigate the tectonic setting of the volcanic edifice at Mt. Baekdu by analyzing petrochemical characteristics of Holocene felsic volcanic rocks distributed in the Baekdusan stratovolcano edifice and summit of the Cheonji caldera rim, as well as Pleistocene mafic rocks of the Gaema lava plateau and Changbaishan shield volcano edifice. During the early eruption phases, mafic eruption materials, with composition ranging from alkali basalt to trachybasalt, or from subalkaline (tholeiitic) basalt to basaltic andesite formed the Gaema lava plateau and Changbaishan shield volcanic edifice, whereas the Baekdusan stratovolcano edifice and Holocene tephra deposits near the summit of the Cheonji caldera comprises trachytic and rhyolitic compositions. Analysis results revealed bimodal compositions with a lack of 54-62 SiO₂, between the felsic and mafic volcanic rocks. This suggested that magmatic processes occurred at the locations of extensional tectonic settings in the crust. Mafic volcanic rocks were plotted in the field of within-plate volcanic zones or between within-plate alkaline and tholeiite zones on the tectonic discrimination diagram, and it was in good agreement with the results of the TAS diagram. Felsic volcanic rocks were plotted in the field of within-plate granite tectonic settings on discrimination diagrams of granitic rocks. None of the results were plotted in the field of arc islands or continental margin arcs. The primitive mantle-normalized spider diagram did not show negative (-) anomalies of Nb and Ti, which are distinctive characteristics of subduction-related volcanic rocks, but exhibited similar patterns of ocean island basalt. Trace element compositions showed no evidence of, magmatic processes related to subduction zones, indicating that the magmatic processes forming the Baekdusan volcanic field occurred in an intraplate environment. The distribution of shallow earthquakes in this region supports the results. The volcanic rocks of the Baekdusan volcanic field are interpreted as the result of intraplate volcanism originating from the upwelling of mantle material during the Cenozoic era.