• Journal of Chest Surgery
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• v.24 no.3
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• pp.310-321
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• 1991

Between April 1986 and September 1990, 34 patients with a single or dominant right ventricle underwent modified Fontan procedure for definite palliation in Seoul National University Children`s Hospital. Their age at operation ranged from 8 months to 14 years [Mean 5.5 years]. The ventricular chamber was solitary and of indeterminate trabecular pattern in 6 patients. 28 patients had posteriorly located rudimentary chamber, all of which were trabecular pouches having no communication with outlet septum. The patterns of atrioventricular connection were common inlet[9], double inlet [11], left atrioventricular valve atresia [12] and right atrioventricular valve atresia with L-loop [2]. Pulmonary outflow tracts were atretic in 7 patients and stenotic in 26 patients. Major associated anomalies included anomalous systemic venous drainage [15], dextrocardia [12] and total anomalous pulmonary venous connection[3]. Shunt operations were previously performed in 13 patients and pulmonary artery banding and atrial septectomy in 1 patients. Surgery included intraatrial baffling in 26 patients, bidirectional cavopulmonary shunt in 13 patients, atrioventricular valve obliteration in 3 patients and atrioventricular valve replacement in 3 patients. Central venous pressure measured postoperatively at intensive care unit ranged from 18cm H2O to 28cm H2O [mean 23.2cm H2O]. Hospital mortality was 35.3% [12/34], all died out of low output syndrome. Suspected causes of low output syndrome include ventricular dysfunction [8], hypoplastic or tortuous pulmonary artery [2] and elevated pulmonary vascular resistance [2]. 19 patients had 31 major complications including low output syndrome [18], arrhythmia [4], acute renal failure [3] and respiratory failure [3]. Mortality rate was significantly higher in the groups receiving intraatrial baffling and AV valve replacement respectively [p<0.05]. 20 patients were followed up postoperatively with the mean follow-up period 15.0$\pm$11.6 months. There were no late death and follow-up catheterization was performed in 10 patients. Mean right atrial pressure was 15.4$\pm$6.8mmHg and ventricular contraction was reasonable in all but one case. Thus, Fontan principle can be applied successfully to all the patients with complex cardiac anomaly of single ventricle variety and better results can be anticipated with judicious selection of patient and improvement of postoperative care.

• Journal of Chest Surgery
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• v.23 no.6
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• pp.1118-1127
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• 1990

Arterial switch operation for repair of nineteen cases of transposition of the great arteries associated with ventricular septal defect and three cases with double outlet right ventricle with subpulmonary ventricular septal defect[Taussig-Bing type DORV] was performed from November 1987 to September 1990 at the Seoul National University Children`s Hospital. Sixteen of them were under six months of age, and three were under one year of age with body weight ranged from three to fourteen kilograms. Preoperative cardiac catheterization was done in eighteen patients, in which the pressure of the left ventricle was greater than 70% of the right ventricle in all but one. Patent ductus was associated in thirteen cases[68.4%] of TGA+VSD, and atrial septal defect or patent oval foramen was in sixteen cases. Four atrial septostomy, one modified Blalock- Taussig shunt, one pulmonary artery banding, one coarctoplasty using subclavian arterial flap, were perfomed before arterial switch operation. There were five hospital deaths, all in the. patients with transposition of the great arteries with ventricular septal defect[overall mortality rate 22.7%]. Lecompte Maneuver was used in all patients, and in all patient the U-shaped flap of coronary arteries were transposed to V-shaped cleavage created in the neoaorta. Arterial defect in the neopulmonary artery was covered with 0.0625% Glutaraldehyde fixed autogenous pericardium There have been no late deaths, Postoperative cardiac catheterization and angiocardiogram in four patients has revealed no stenosis in the neopulmonary artery or neoaorta with reasonable P[RV/LV], Anatomic correction for transposition and double outlet right ventricle with subpulmonary ventricular septal defect would seem to be a good operative alternative to intraatrial switch procedures, with the advantage of incorporating the left ventricle to systemic circulation.

• Journal of Korean Society of Transportation
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• v.17 no.3
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• pp.31-46
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• 1999

In the middle of motorization, the traffic problems become serious social problems in Korea. The walking environment is not only a topic which restores the community spirit of a city or society but also a lever which renovates the future space of the city environment-friendly. Thus, the Purpose of this study is to suggest the new criteria of walkway level of service adopting the concepts of safety. convenience, comfort, environment, security, and continuity in addition to present pedestrian flow rate, and to provide basic data for walkway plan in Korea. In order to analyze the adequacy of the present walkway level of service criteria, the walkways of which service levels were A, C, E according to USHCM were selected as study walkways, and an interview surrey was conducted to compare the three service levels with those that pedestrians evaluate actually. Also, another interview survey was conducted to analyze the service conditions and satisfaction level at the walkways of high service levels(A and B). For the establishment of more reasonable walkway level of service criteria. the survey of pedestrian\`s consciousness for walkway service was conducted. Based on the survey results, the new criteria for the evaluation of walkway service were selected and the six levels of service for each criterion was analyzed: so the comprehensive criteria of walkway level of service were suggested.

• Journal of the Earthquake Engineering Society of Korea
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• v.14 no.2
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• pp.27-36
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• 2010

It is well known that the shear strength of an RC column subjected to a lateral force decreases with the increase of the displacement ductility of column. This decreasing rate of shear strength is quite dependent on the initial shear strength. Therefore, the evaluation of the initial shear strength is important to predict the shear strength with reasonable accuracy. The shear behavior is complex because many parameters, such as the sectional shape, aspect ratio, axial force, longitudinal bars and ductility, are mutually interactive. In this study, the initial shear strength has been investigated by experiments varying parameters such as the aspect ratios, void ratios, ratio of longitudinal bars and sectional types. A new empirical equation for the initial shear strength, considering the ratio of the longitudinal bars, has been proposed and its validity has been assessed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.1
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• pp.21-28
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• 2016

A typical heat exchanger, found in many industrial sites, is made up of a large number of unitary cells, which causes difficulties when carrying out full-scale three-dimensional numerical simulations of the heat exchanger to analyze the aero-thermal performance. In the present study, a three-dimensional numerical study using a porous media model was carried out to evaluate the performance of the heat exchanger modelled in two different ways : full-scale and simplified. The pressure drop in the air side and gas side along with the overall heat transfer rate were calculated using a porous media model and the results were then compared to results obtained with a one-dimensional flow network model. The comparison between the results for two different geometries obtained using a porous media model and a one-dimensional flow network model shows good agreement between the simplified geometry and the one-dimensional flow network model. The full-scale geometry shows reasonable differences caused by the geometry such as sudden expansion and contraction.

• 한국HCI학회:학술대회논문집
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• 2007.02a
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• pp.667-674
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• 2007

Facial expressions provide significant clues about one's emotional state; however, it always has been a great challenge for machine to recognize facial expressions effectively and reliably. In this paper, we report a method of feature-based adaptive motion energy analysis for recognizing facial expression. Our method optimizes the information gain heuristics of ID3 tree and introduces new approaches on (1) facial feature representation, (2) facial feature extraction, and (3) facial feature classification. We use minimal reasonable facial features, suggested by the information gain heuristics of ID3 tree, to represent the geometric face model. For the feature extraction, our method proceeds as follows. Features are first detected and then carefully "selected." Feature "selection" is finding the features with high variability for differentiating features with high variability from the ones with low variability, to effectively estimate the feature's motion pattern. For each facial feature, motion analysis is performed adaptively. That is, each facial feature's motion pattern (from the neutral face to the expressed face) is estimated based on its variability. After the feature extraction is done, the facial expression is classified using the ID3 tree (which is built from the 1728 possible facial expressions) and the test images from the JAFFE database. The proposed method excels and overcomes the problems aroused by previous methods. First of all, it is simple but effective. Our method effectively and reliably estimates the expressive facial features by differentiating features with high variability from the ones with low variability. Second, it is fast by avoiding complicated or time-consuming computations. Rather, it exploits few selected expressive features' motion energy values (acquired from intensity-based threshold). Lastly, our method gives reliable recognition rates with overall recognition rate of 77%. The effectiveness of the proposed method will be demonstrated from the experimental results.

• Journal of Environmental Health Sciences
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• v.35 no.2
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• pp.78-85
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• 2009

In this study, the hazard rate of the indoor environment of Children's Educational Facilities in Seoul was conducted, in order to determine how the indoor environments of these facilities, where infants and children spend the most time of their away from home day, can effect their health. The way of measurement and analysis were done according to the Indoor Air Quality Standard Method, and the Risk Assessment was accomplished with several significant ways - Hazard Identification, Exposure Assessment, Dose-response Assessment, Risk Characterization, which are deighed by National Research Council (NRC). On each exposure factors, documentary and questionary research such as Epidemiological study and Toxicological study were conducted. The result of the CTE (Central tendency exposure) of Formaldehyde and Benzene by Monte-Carlo simulation was $6.79{\times}10^{-6}$, $2.50{\times}10^{-7}$ which in the case of Formaldehyde exceeded the permitted standard ($10^{-6}$) of the US EPA. The RME(Reasonable maximum exposure) was $7.31{\times}10^{-5}$, $2.65{\times}10^{-6}$ which did not exceed $10^{-4}$, the maximum permitted standards in the US EPA.

• Tuberculosis and Respiratory Diseases
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• v.71 no.4
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• pp.249-253
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• 2011

Background: Mycobacterial infection is a problem throughout the world along with the increase of immunocompromised patients. For this reason, there have been many methods for faster and more accurate diagnosis. In this study, we evaluated several laboratory methods for mycobacterial infection. Methods: From January to December 2009, 635 specimens were cultured with mycobacteria growth indicator tube (MGIT) and Ogawa media. Polymerase chain reaction (PCR) was performed with the AdvanSure tuberculosis (TB)/non-tuberculosis mycobacterium (NTM) real-time PCR Kit (LG Life Sciences, Seoul, Korea). The 69 samples showing positive culture results were identified with the AdvanSure Mycobacteria Genotyping Chip Kit (LG Life Science, Seoul, Korea). Results: Sixty-nine (10.9%) out of 635 samples showed positive results for mycobacterial culture. Among the 635 samples, 64 were positive in MGIT, but only 42 were positive in Ogawa media. Of the 635 samples, 607 (95.6%) showed the same results between MGIT and Ogawa and the results of 579 (95.4%) were also consistent with the TB/NTM real-time PCR results. However, in the case of NTM, only one (1/24, 4.2%) was positive in PCR. In the Mycobacteria genotyping chip analysis, the most frequently identified NTM species in descending order were M. avium, M. intracellulare, M. chelonae and M. abscessus. Conclusion: Culturing with a combination of MGIT and Ogawa is recommended to increase the recovery rate of mycobacteria. Although PCR missed a reasonable number of NTM, it is faster and usually gives results that concur with those from the culture. The appropriate combination of diagnostic methods with clinical correlation are necessary.

• Journal of Arbitration Studies
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• v.29 no.4
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• pp.165-186
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• 2019

The parties are jointly and severally liable to pay to the arbitrators such reasonable fees and expenses (if any) as are appropriate in the circumstances. Any party may apply to the court (upon notice to the other parties and to the arbitrators) which may order that the amount of the arbitrators' fees and expenses shall be considered and adjusted by such means and upon such terms as it may direct. Arbitrators' fees and expenses are calculated on the basis of informal time fees determined by the arbitrators themselves, and the fees and expenses also vary greatly depending on the nature of the case. Obviously, when appointing a member of the LMAA as an arbitrator, it is rare to negotiate the fees and expenses with the arbitrator and to make specific arrangements for the fees and expenses. And it is common for between an arbitrator and a party to have an arbitrator agreement only in accordance with LMAA Terms. And it is common for between an arbitrator and a party to have an arbitrator agreement only in accordance with LMAA Terms. The purpose of this study analyzes the structure of arbitrators' fees and expenses under the UK Arbitration Act and LMAA Terms 2017. The contents can be divided into the relationship between the arbitrator and the parties (the claim of fees, the type of fees) and the relationship between the parties(the burden rate of arbitrators' fees). In this regard, this study suggests the implications after comparatively analyzing the UK Arbitration Act and the LMAA Terms 2017.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.7
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• pp.13-23
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• 2009

In this paper, the network performance of a turbo coded optical code division multiple access (CDMA) system with cross-layer, which is between physical and network layers, concept is analyzed and simulated. We consider physical and MAC layers in a cross-layer concept. An intensity-modulated/direct-detection (IM/DD) optical system employing pulse position modulation (PPM) is considered. In order to increase the system performance, turbo codes composed of parallel concatenated convolutional codes (PCCCs) is utilized. The network performance is evaluated in terms of bit error probability (BEP). From the simulation results, it is demonstrated that turbo coding offers considerable coding gain with reasonable encoding and decoding complexity. Also, it is confirmed that the performance of such an optical CDMA network can be substantially improved by increasing e interleaver length and e number of iterations in e decoding process. The results of this paper can be applied to implement the indoor optical wireless LANs.