• Journal of the Korean Society for Aviation and Aeronautics
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• v.31 no.2
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• pp.89-94
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• 2023

Recently, domestic small airport development plans are being promoted centering on islands, and among them, Baengnyeong Island Airport is located very close to North Korea due to its geographical characteristics. In particular, since it is located in the P-518, which is prohibited airspace, it is essential to configure the arrival/departure flight procedure route similarly to the current ship in terms of securing flight safety. Therefore, in this study, a plan for airport location and facility scale was proposed by focusing on the runway operated for the purpose of aircraft operation through consultations with the Ministry of National Defense. It was proposed to meet the standards of the Airport Facility Act as an airport dedicated to domestic flights for airside facilities such as runway length and direction, target aircraft, landing pad, apron, runway and taxiway width appropriate for the topographical characteristics of Baengnyeong Island. As a result, the flight procedure is generally established as a two-way visual flight, but the 10-way arrival/departure procedure was planned to be changed to an instrument (non-precision) according to the specificity of the region. In addition, a flight procedure was established and presented for safe and systematic operation by reflecting the changes in airport facility size (landing pad, runway end safety area, etc.) following the change in instrument flight procedure in the visual flight procedure.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.1
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• pp.137-147
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• 2017

Wartime warship damage rate indicates how much damage of friend warships shall have occurred during naval battles accomplished under specific war operational plans. The wartime damage rate analysis provides the baseline of wartime resources requirements. If wartime damage rate is overestimated, the national finance will get to negative effects because of exceeding the budget for inventory, operation, and maintenance of resources. Otherwise, if wartime damage rate is underestimated, the national defense will lose in the war because of lack of critical resources. In this respect, it is important to estimate the wartime damage rate accurately and reasonably. This paper proposes a systematic procedure to estimate the wartime warship damage rate. The procedure consists of five steps; force analysis, operation plan analysis, input variable definition, simulation modeling, and output analysis. Since the combat simulation model is regarded as the main tool to estimate damage rate, the procedure is focused on the development of model and experiments using the model. A case study with virtual data is performed to demonstrate the effectiveness of the developed procedure.

• Journal of Chest Surgery
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• v.51 no.1
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• pp.53-56
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• 2018

Patients with double-inlet left ventricle usually have a small ascending aorta. In the Norwood procedure, which involves a staged operation, a neoaorta is constructed with a homograft, and the pulmonary artery plays a role in the systemic circulation. Dilatation or aneurysmal changes can occur over time due to the exposure of the neoaorta to systemic pressure, which may induce adverse effects on adj acent structures. We report a rare case of surgical repair for neoaortic root dilataiton with aortic regurgitation, compressing the left pulmohary artery, in a patient who underwent the Norwood procedure.

• Journal of Chest Surgery
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• v.8 no.1
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• pp.9-12
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• 1975

Four patients with postpneumonectomy empyema were treated successfully by modification of Clagett`procedure. Their primary diseases were chronic bronchiectasis, empyema with bronchopleural fisula, pulmonary tuberculosis, and pyohemothorax. The time interval between 1st and 2nd operation was 26.5 months in average. The pleural space was irrigated with various kinds of antiseptic solutions for 23.3 days in average and debrided, filled with antibiotic saline solution. After the procedure, patients had no recurrences of empyema and discharged from hospital after brief days. (averages: 15.5 days)

• Journal of Korean Society of Transportation
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• v.25 no.6
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• pp.129-140
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• 2007

The planning procedure of a transit operation consists of design, operation, and evaluation according to the research characteristics. There are some review studies on the operation and evaluation procedure, but the research on the design procedure has not yet been organized systematically. In this study, the research on transit system design was reviewed and the model structure and its solution method were arranged. The decision variables of the design procedure are network structure, line spacing or position, stop spacing, dispatching headway, and fleet size. In the analytical research on design procedure, system total cost is generally used as the objective function. System total cost is comprised of user cost, which is the sum of user access, waiting, and travel cost, and operating cost. Total cost of the transit system, used as the objective function, has the unique minimum because it is differentiable. There is a certain decision variable that makes the derivative of the objective function equal to zero and the second derivative of the objective function is positive. Therefore the decision variable that makes the first derivative of the objective function zero is the optimum that minimizes the objective function, and each of the cost components of the objective function become the same. This study is expected to help understanding about the research on the design procedure of transit operation planning and to help be a catalyst for relevant research.

• Journal of Positioning, Navigation, and Timing
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• v.11 no.1
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• pp.51-58
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• 2022

Korea Augmentation Satellite System (KASS) is a Satellite Based Augmentation System (SBAS) system under development in South Korea and aims to provide air navigation services after 2023. In order to provide reliable service, detailed design for the operation of this system is required. This paper proposes a detailed operation-based designs based on mission, architecture, operation definition of the system. For the stable operation of the system, an operation organization was designed and operation activities were classified in consideration of the architecture and function of the system. Detailed operation procedures were designed according to this classification and operation procedures related to the command and configuration of subsystem were verified on the Integration, Verification and Qualification (IVQ) platform for integrated testing and verification. The proposed operation concepts and procedures will be continuously confirmed and verified during verification, qualification and service preparation, and will be updated event after official KASS service.

• Clinics in Shoulder and Elbow
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• v.26 no.4
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• pp.445-454
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• 2023

The Latarjet procedure is a surgical procedure that can effectively restore glenohumeral stability, especially in patients with anterior shoulder instability and glenoid bone loss. Many studies have shown comparable clinical outcomes between patients undergoing the arthroscopic Latarjet procedure and those undergoing traditional open methods or other glenohumeral joint stabilization procedures. However, the arthroscopic Latarjet procedure is a challenging technique due to the unfamiliar portal placements, proximity of neurovascular structures, and serious postoperative complications. The arthroscopic Latarjet procedure has not yet been widely applied, and a clear understanding of the anatomical structure and the precise methods is required prior to operation performance. Satisfactory clinical outcomes can be achieved by thorough preoperative planning and proper implant fixation methods.

• Water Engineering Research
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• v.3 no.1
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• pp.57-62
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• 2002

This research is intended to integrate long-term operation rules and real time operation policy for conservation & flood control in a reservoir. The familiar Yield model has been modified and used to provide long-term rule curves. The model employs linear programming technique under given physical conditions, i.e., total capacity, dead storage, spillways, outlet capacity and their respective elevations to find required and desired minimum storage fur different demands. To investigate the system behavior resulting from the above-mentioned operating policy, i.e., the rule curves, the simulation model was used. Results of the simulation model show that the results of the optimization model are indeed valid. After confirmation of the above mentioned rule curves by the simulation models, gate operation procedure was merged with the long term operation rules to determine the optimum reservoir operating policy. In the gate operation procedure, operating policy in downstream flood plain, i.e., determination of damaging and non-damaging discharges in flood plain, peak floods, which could be routed by reservoir, are determined. Also outflow hydrograph and variations of water surface levels for two known hydrographs are determined. To examine efficiency of the above-mentioned models and their ability in determining the optimum operation policy, Esteghlal reservoir in Iran was analyzed as a case study. A numerical model fur the solution of two-dimensional dam break problems using fractional step method is developed on unstructured grid. The model is based on second-order Weighted Averaged Flux(WAF) scheme with HLLC approximate Riemann solver. To control the nonphysical oscillations associated with second-order accuracy, TVD scheme with SUPERBEE limiter is used. The developed model is verified by comparing the computational solutions with analytic solutions in idealized test cases. Very good agreements have been achieved in the verifications.

• Advances in pediatric surgery
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• v.10 no.1
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• pp.1-8
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• 2004

A re-pull-through operation for Hirschsprung's disease is performed when the primary operation has failed because of the remnant or acquired aganglionosis, anastomotic stricture and/or fistula. The purpose of this study is to review our experience of the re-pull-through procedure for Hirschsprung's disease. From May 1978 to July 2003, 26 patients who underwent re-pull-through operations at the Department of Pediatric Surgery, Seoul National University Children's Hospital, were studied retrospectively by means of chart review as well as telephone interview. The mean age at primary operation and re-operation were llmonths (2 months - 10 years) and 43 months (1 year - 23 years 3 months), respectively. Initial operation for Hirschsprung's disease was Duhamel's procedure in 17, Swenson's in 6 and Soave's 3. Causes of failure of primary operation were remains of secondary aganglionic segment (n=23), vascular arcade injury (n= 1), rectoperineal fistula (n=2, due to mesenteric torsion and poor blood supply), Mean interval between the primary operation and the re-operation was 34 months (6 months-22 years). Reoperation methods were Soave's in 12, Duhamel's in 8, APSP (abdomino-posterosagittal pull-through procedure) in 5, and Swenson's in 1 case. In 2 cases of repeated rectoperineal fistula or rectourethral fistula, re-APSP were performed 3 times, respectively. A total of 29 re-pull-through operations were performed. Postoperative complications were wound infection (n=1), adhesive ileus (n=1), rectoperineal fistula (n=3), rectourethral fistula (n=2), and death due to pulmonary embolism (n=1). Mean follow up period of reoperation was 78 months (1 month-23years). In current state, 2 patients have an ileostomy because of repeated rectoperineal fistula and rectourethral fistula. Of the remaining 23 patients, 21(91 %) are totally continent with or without minimal soiling. Reoperation for Hirschsprung's disease was effective and safe for the patients complicated to the initial pull-through operation.

• Journal of Periodontal and Implant Science
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• v.8 no.1
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• pp.26-26
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• 1978