• Journal of Chest Surgery
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• v.29 no.9
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• pp.951-958
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• 1996

Bet een November 1991 and December 1993, twelve patients (Male: 2, Female: 10) who had mitral valve disease without primary pulmonary disease underwent mitral valve replacement. The pulmonary function test (PFT) was performed preoperatively and postoperatively (mean, 9 months after operation). Mitral valve replacement was indicated for mitral stenosis in 9 patients and for mitral insufficiency in 3 patients. Preoperative WHh functional class were 111 in 11 patients and class rV in 1 patient. Postoperatively, ten patients (83 %) were classified into NYHA functional class 1. There was a significant decrease in cardiothoracic ratio (CTR) postoperatively (p< 0.05). The pulmonary function before operation was low compared with predicted values in vital capacity (VC) and forced mid-expiratory flow (FEF 25∼75 %). The FEF 25%-75% and maximal voluntary ventilation (MW) were low compared with predicted values postoperatively. There was no significant difference in the pulmonary function before an after op- eration. Twelve patients were divided into 2 groups according to the early postoperative NYHA functional class. In class I group, the postoperative pulmonary function was significantly improved in 6 parameters (RV, FRC, TLC, FEVI , FEVI /FVC, and FEF 25∼75%), but in class ll group, there was no significant change in the pulmonary function after operation.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.71.3-71.3
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• 2015

Deep UBVI and $H{\alpha}$ photometry of the ${\eta}$ Carina nebula, one of the brightest nebulae on the sky, was obtained with the CTIO 4m telescope and MOSAIC II CCD Camera to determine the initial mass function down to low-mass (~1 M¤) stars. We modified the spatial variation coefficients in transformation relations of the MOSAIC II CCD. From the cross-identification of optical sources with previous surveys in X-ray, near-infrared, and mid-infrared, a clear PMS sequence is revealed in the optical color-magnitude diagrams down to V=23 mag. Our previous SSO 1m UBVI data for Trumpler 14 (Tr 14) and Trumpler 16 (Tr 16) region, and additional SSO 1m UBVI data for Trumpler 15 (Tr 15) region were combined with the CTIO 4m data to re-examine the reddening law and distance of the young open clusters in the ${\eta}$ Carina nebula. From the new photometric data for Tr 15 region, we report that RV[=AV/E(B-V)], the total-to-selective extinction ratio, decreases from southern part of the nebula (Tr 14 and Tr 16) to northern part (Tr 15) in our field of view.

• Journal of Chest Surgery
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• v.34 no.11
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• pp.854-857
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• 2001

Double-outlet left ventricle(DOLV) is a rare congenital cardiac malformation, defined as the origin of both the aorta and the pulmonary artery being entirely or predominantly above the morphologically left ventricle, which is difficult to diagnose accurately. A 3-year old male was admitted for cyanosis and dyspnea. At the age of 2 months, he had undergone pulmonary artery banding and coarctoplasty. He was diagnosed as DOLV with subaortic ventricular septal defect(VSD). Biventricular repair was achieved by patch closure of VSD, primary closure of PFO, and pulmonary trunk translocation from left ventricle to right ventricle. The advantages of this procedure using native tissue for right ventricular outflow tract reconstruction are growth potential and preserved valve function, which contribute to a decreased likelihood of reoperation related to the right ventricular dysfunction related to pulmonary insufficiency.

• Journal of Chest Surgery
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• v.24 no.2
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• pp.153-160
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• 1991

Tetralogy of Fallot was repaired by a transatrial-transpulmonary approach in 91 of 250 patients treated surgically [including redo operations] between April 1986 and December 1989. Their age ranged from 6 months to 14 years [mean 39.7 months]. Associated cardiovascular anomalies were right aortic arch [n=22], ASD [n=12], PDA [n=5], persistent left SVC [n=5], and others [n=6]. PA index was measured pre-operatively since 1987 to estimate pulmonary artery size and safe total correction[mean 289$\pm$110mm2/BSA]. Eight patients received previous shunt take down procedure concomitantly. Pulmonary arteriotomy was extended through small pulmonary annulus to a minimal distance upon the right ventricular infundibulum and transannular patch was applied in 38 patients [41.3%], in 31 of them monocuspid patch was utilized. pRV/LV was measured at operation room in 77 patients [mean 0.58$\pm$0.36]. Operative mortality was 6.6% [6/91]. The causes of death were low cardiac output [n=5], arrhythmia[n=1] and respiratory failure [n=1]. At follow-up between 12 months and 57 months [mean 30.8 months] most patients were in New York Heart Association class I without cardiac medication. There was no late death, but reoperations were required in 3 patients to relieve residual right ventricular outflow obstruction. Thus successful repair of tetralogy of Fallot can be accomplished in most patients including infants by transatrial-transpulmonary approach and the better result can be anticipated with respect to postoperative right ventricular function and arrhythmia than the conventional transventricular approach.

• Journal of Chest Surgery
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• v.29 no.1
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• pp.86-89
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• 1996

This is a report of successful conversion arterial switch operation for failed Sunning procedure in transposition of the great arteries(TGA) with ventricular septal defect(VSD). A 15 month-male patient was admitted due to intractable congestive heart failure after Sunning operation was done at the age of 8 months. Angiography revealed marked dysfunction of the morphologic right ventricle with tricuspid regurgitation and residual VSD. The pulmonary ventricle 1 systemic ventricle pressure ratio' of 75/85 at catheter study enabled us to do the take down of denning repair, patch closure of VSD and arterial switch without pulmonary artery banding. After the operation, the baby showed good growth with normal ventricular function.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1997.10a
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• pp.111-114
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• 1997

Usually, Evolutionary Algorithms are considered more efficient for optimal system design, However, the performance of the system is determined by fitness function and system environment. In this paper, in order to overcome the limitation of the performance by this factor, we propose a co-evolutionary method that two populations constantly interact and coevolve. In this paper, we apply coevolution to neural network's evolving. So, one population is composed of the structure of neural networks and other population is composed of training patterns. The structure of neural networks evolve to optimal structure and, at the same time, training patterns coevolve to feature patterns. This method prevent the system from the limitation of the performance by random design of neural network structure and inadequate selection of training patterns. In this time neural networks are trained by evolution strategies that are able to apply to the unsupervised learning. And in the coding of neural networks, we propose the method to maintain nonredundancy and character preservingness that are essential factor of genetic coding. We show the validity and the effectiveness of the proposed scheme by applying it to the visual servoing of RV-M2 robot manipulators.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.63.3-63.3
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• 2019

Nearby young moving groups (NYMGs hereafter) are gravitationally unbound loose young stellar associations located within 100 pc of the Sun. Since NYMGs are crucial laboratories for studying low-mass stars and planets, intensive searches for NYMG members have been performed. For identification of NYMG members, various strategies and methods have been applied. As a result, the reliability of the members in terms of membership is not uniform, which means that a careful membership re-assessment is required. In this study, I developed a NYMG membership probability calculation tool based on Bayesian inference (Bayesian Assessment of Moving Groups: BAMG). For the development of the BAMG tool, I constructed ellipsoidal models for nine NYMGs via iterative and self-consistent processes. Using BAMG, memberships of claimed members in the literature (N~2000) were evaluated, and 35 per cent of members were confirmed as bona fide members of NYMGs. Based on the deficiency of low-mass members appeared in mass function using these bona fide members, low mass members from Gaia DR2 are identified. About 2000 new M dwarf and brown dwarf candidate members were identified. Memberships of ~70 members with RV from Gaia were confirmed, and the additional ~20 members were confirmed via spectroscopic observation. Not relying on previous knowledge about the existence of nine NYMGs, unsupervised machine learning analyses were applied to NYMG members. K-means and Agglomerative Clustering algorithms result in similar trends of grouping. As a result, six previously known groups (TWA, beta-Pic, Carina, Argus, AB Doradus, and Volans-Carina) were rediscovered. Three the other known groups are recognized as well; however, they are combined into two new separate groups (ThOr+Columba and TucHor+Columba).

• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.471-482
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• 1996

Early recognition of coalescence in pneumoconiotic lesions is important because such coalescence is associated with the respiratory symptoms and deterioration of lung function. This complicated form of pneumoconiosis also has worse prognosis than does simple pneumoconiosis. High resolution computerized tomography(HRCT) provides significant additional information on the stage of the pneumoconiosis because it easily detects coalescence of nodules and emphysema that may not be apparent on the simple radiograph. The purpose of this study is to clarify the role of HRCT in detection of large opacity and the relationship of change between the coalescence of nodules or emphysema and lung function in dust exposed workers. 1. There was good correlation between the HRCT grade of pneumoconiosis and ILO category of profusion. 5(9.09%) in 55 study population had confluent nodule extending eve, two o, more cuts on HRCT. HRCT could identify the pneumoconiotic nodules which was not found by simple radiogrphy in 6 workers with category 0/0. 2. No significant difference was observed coalescence of nodules and emphysema by dust type. 3. There was no significant difference in pulmonary function according to ILO and HRCT classification. 4. HRCT could detect the significant reduction in $FEV_1,\;FEV_1/FVC$, PEFR, $FEF_{25},\;FEF_{50},\;and\;FEF_{75}$ and remarkable increase in RV and TLC in study persons with emphysema compared with non-emphysema group. 5. Emphysema was found more often in nodules-coalescence group than small opacity group by HRCT. We found that HRCT could easily detect areas of coalescence and complicated emphysema compared to plain chest X-ray. Also our data suggest that it is primarily the degree of emphysema rather than the degree of pneumoconiosis that determines the level of pulmonary function.

• Tuberculosis and Respiratory Diseases
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• v.43 no.3
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• pp.367-376
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• 1996

Background : The diagnosis of emphysema during life is based on a combination of clinical, functional, and radiographic findings, but this combination is relatively insensitive and nonspecific. The development of rapid, high-resolution third and fourth generation CT scanners has enabled us to resolve pulmonary parenchymal abnormalities with great precision. We compared the chest HRCT findings to the pulmonary function test and arterial blood gas analysis in pulmonary emphysema patients to test the ability of HRCT to quantify the degree of pulmonary emphysema. Methods : From october 1994 to october 1995, the study group consisted of 20 subjects in whom HRCT of the thorax and pulmonary function studies had been obtained at St. Mary's hospital. The analysis was from scans at preselected anatomic levels and incorporated both lungs. On each HRCT slice the lung parenchyma was assessed for two aspects of emphysema: severity and extent. The five levels were graded and scored separately for the left and right lung giving a total of 10 lung fields. A combination of severity and extent gave the degree of emphysema. We compared the HRCT quantitation of emphysema, pulmonary function tests, ABGA, CBC, and patients characteristics(age, sex, height, weight, smoking amounts etc.) in 20 patients. Results : 1) There was a significant inverse correlation between HRCT scores for emphysema and percentage predicted values of DLco(r = -0.68, p < 0.05), DLco/VA(r = -0.49, p < 0.05), FEV1(r = -0.53, p < 0.05), and FVC(r = -0.47, p < 0.05). 2) There was a significant correlation between the HRCT scores and percentage predicted values of TLC(r = 0.50, p < 0.05), RV(r = 0.64, p < 0.05). 3) There was a significant inverse correlation between the HRCT scores and PaO2(r = -0.48, p < 0.05) and significant correlation with D(A-a)O2(r = -0.48, p < 0.05) but no significant correlation between the HRCT scores and PaCO2. 4) There was no significant correlation between the HRCT scores and age, sex, height, weight, smoking amounts in patients, hemoglobin, hematocrit, and wbc counts. Conclusion : High-Resolution CT provides a useful method for early detection and quantitating emphysema in life and correlates significantly with pulmonary function tests and arterial blood gas analysis.

• Smart Structures and Systems
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• v.16 no.2
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• pp.243-262
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• 2015

Optimal sensor placement (OSP) is a critical issue in construction and implementation of a sophisticated structural health monitoring (SHM) system. The uncertainties in the identified structural parameters based on the measured data may dramatically reduce the reliability of the condition evaluation results. In this paper, the information entropy, which provides an uncertainty metric for the identified structural parameters, is adopted as the performance measure for a sensor configuration, and the OSP problem is formulated as the multi-objective optimization problem of extracting the Pareto optimal sensor configurations that simultaneously minimize the appropriately defined information entropy indices. The nondirective movement glowworm swarm optimization (NMGSO) algorithm (based on the basic glowworm swarm optimization (GSO) algorithm) is proposed for identifying the effective Pareto optimal sensor configurations. The one-dimensional binary coding system is introduced to code the glowworms instead of the real vector coding method. The Hamming distance is employed to describe the divergence of different glowworms. The luciferin level of the glowworm is defined as a function of the rank value (RV) and the crowding distance (CD), which are deduced by non-dominated sorting. In addition, nondirective movement is developed to relocate the glowworms. A numerical simulation of a long-span suspension bridge is performed to demonstrate the effectiveness of the NMGSO algorithm. The results indicate that the NMGSO algorithm is capable of capturing the Pareto optimal sensor configurations with high accuracy and efficiency.