• Nuclear Engineering and Technology
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• 제44권4호
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• pp.379-386
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• 2012

A symptom-based procedure with a critical safety function monitoring system has been established to reduce the operator's diagnosis and cognitive burden since the Three-Mile Island (TMI) accident. However, it has been reported that a symptom-based procedure also requires an operator's cognitive efforts to cope with off-normal events. This can be caused by mismatches between a static model, an emergency operating procedure (EOP), and a dynamic process, the nature of an ongoing situation. The purpose of this study is to share the evidence of mismatches that may result in an excessive cognitive burden in conducting EOPs. For this purpose, we analyzed simulated emergency operation records and observed some operator behaviors during the EOP operation: continuous steps, improper description, parameter check at a fixed time, decision by information previously obtained, execution complexity, operation by the operator's knowledge, notes and cautions, and a foldout page. Since observations in this study are comparable to the results of an existing study, it is expected that the operational behaviors observed in this study are generic features of operators who have to cope with a dynamic situation using a static procedure.

• 한국항공운항학회지
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• 제25권4호
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• pp.170-176
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• 2017

In recent years, Unmanned Aerial Vehicles (UAVs) were actively developed in various fields. In development process of UAVs, flight test is performed to ensure that minimum safety requirements and technical requirements are met. By constructing flight test infrastructure such as takeoff and landing facilities, operation procedure, and equipments, flight test can be performed effectively. In this paper, operation procedures of civil UAV's flight test are proposed. The procedures proposed are composed by two main steps: first, planning and permitting procedure of flight test. Secondly, execution and control procedure of flight test.

• Journal of Chest Surgery
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• 제23권5호
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• pp.936-943
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• 1990

The Fontan operation for tricuspid atresia was first performed in 1968[Fontan and Baudet 1971] and several technical modifications of procedure were developed. We have experienced a case of modified Fontan operation for tricuspid atresia type Ic who was 5 years old female. She had previous palliative procedure \ulcornerpulmonary artery banding due to excessively increased pulmonary blood flow. The modified Fontan operation was right atrium to right ventricle connection with valve-bearing conduit. The result was good and the patient was discharged 20 days after operation.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.501-504
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• 2005

In general, most incomplete communication link setup between satellite and ground station right after separation from launcher come from less accurate orbital vector ground station uses to track the satellite because only predicted orbital state vector is available during first few orbits. This paper describes the developed procedure for successful initial acquisition for KOMPSAT-2 using scanning functions ofK13 antenna system with predicted orbital information. Azimuth scan, raster scan, spiral scan functions were tested with KOMPSA Tl under intentionally degraded orbital information for antenna operation. Through tests, spiral scan function was decided to be best search scan among 3 scans. Developed procedure can assure the successful acquisition only if azimuth offset and time offset value are within +/-2deg and +/-30sec, respectively.

• Journal of Chest Surgery
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• 제26권5호
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• pp.422-426
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• 1993

We report three cases of children who underwent definitive conversion to the Fontan circulation using a new surgical technique, Extracardiac Epicardial Lateral Tunnel. This new procedure allows the operation to be performed as a totally extracardiac operation [especially in ventricular dysfunction] and allows it to be performed in a very small atrium and in cases with unsuitable pulmonary venous drainage.Our data suggest that this procedure may achieve satisfactory hemodynamics of the total cavopulmonary connection.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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• pp.253-256
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• 2001

This paper describes a high speed MAC(Media Access Control) function chip for IEEE 802.11 MAC layer protocol. The MAC chip has control registers and interrupt scheme for interface with CPU and deals with transmission/reception of data as a unit of frame. The developed MAC chip is composed of protocol control block, transmission block, and reception block which supports the BCF function in IEEE 802.11 specification. The test suite which is adopted in order to verify operation of the MAC chip includes various functions, such as RTS-CTS frame exchange procedure, correct IFS(Inter Frame Space)timing, access procedure, random backoff procedure, retransmission procedure, fragmented frame transmission/reception procedure, duplicate reception frame detection, NAV(Network Allocation Vector), reception error processing, broadcast frame transmission/reception procedure, beacon frame transmission/reception procedure, and transmission/reception FIEO operation. By using this technique, it is possible to reduce the load of CPU and firmware size in high speed wireless LAN system.

• 산업공학
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• 제21권1호
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• pp.75-84
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• 2008

It is a difficult task for decision makers(DMs) to choose an appropriate release plan which balances the conflicts between water storage and hydro-electric energy generation in a multi-reservoir operation problem. In this study, we proposed a DEA-based ranking procedure by which the DM can rank the potential alternatives and select the best solution among the Pareto-optimal solutions. The proposed procedure can resolve the problem of mix inefficiency that may cause errors in measuring the efficiency of alternatives. We applied the proposed procedure to the multi-reservoir operation problem for the Geum-River basin and could choose the best efficient solution from the Pareto-set which were generated by the Coordinated Multi-Reservoir Operating Model.

• 대한후두음성언어의학회지
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• 제14권1호
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• pp.10-15
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• 2003

Background and Objectives : Ankyloglossia, commonly known as tongue-tie, is the result of a short, fibrous lingual frenulum or highly attached geioglossus muscle. This condition may cause sucking and swallowing problems, articulation disorders, interference with the tongue's cleansing action, increased the potential for caries, and inability to lick the lips, play a wind instrument, and 'french kiss' Treatment is surgical procedure. In the most cases, horizontal sectioning and mucosal suture(the conventional procedure) is preferred, but in some cases, the Z-plastic procedure is effective. This study is aimed to compare the result of the two procedures. Materials and Methods : Twenty tongue-tie patients underwent operation. Ten patients were treated with the Z-plastic procedure and ten patients were treated with the conventional method randomly. We checked preoperative mobile tongue length, postoperative mobile tongue length, operation time and postoperative wound states. Results : Among the 20 cases of tongue-tie, 2 cases are excepted due to pre-operative state, thus we compared 18 cases of tongue-tie patients. There is no statistically significant difference between the two procedures except in operation time. The Z-plastic procedure apparently needs a little more operating time. Conclusion : Patients treated with the Z-plastic procedures appeared to have better outcomes, but the data shows no statistical significance except in operating time. Consequently, the Z-plastic procedure is indicated in a limited amount of cases.

• Journal of Chest Surgery
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• 제42권1호
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• pp.9-13
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• 2009

서론: 좌심형성부전증후군은 사망률이 높은 질환이다. 이번 연구는 노우드(Norwood) 수술을 거쳐 최종적으로 폰탄 수술을 시행한 좌심형성부전증후군 환자에서 외과적 치료 및 폰탄 수술 후 결과를 알아 보기 위한 것이다. 대상 및 방법: 1997년 10월부터 2005년 5월까지 좌심형성부전증후군으로 노우드 수술을 시행한 21명의 환자 중 최종적으로 폰탄(Fontan) 수술을 시행한 6명의 환자를(M : F=4 : 2) 대상으로 역행적 조사를 하였다. 노우드 수술 시 평균 나이는 $17.3{\pm}10.8$일(9~36일)이었고, 양방향성 글렌수술은 $8.9{\pm}7.1$개월(4.6~23.3개월), 그리고 폰탄 수술은 $32.4{\pm}9.8$개월(20.9~43.9개월)에 시행하였다. 한 명의 환자에서 삼첨판 역류가 보여, 2차 수술 시 판막 성형술을 시행하였다. 모든 환자에서 고어텍스 도관을 이용한 심장외 폰탄 수술(20 mm 2명, 18 mm 4명)을 하였으며 1명에서 개방창(fenestration)을 두었다. 결과: 노우드 수술 사망률은 30% (7/21)이며, 4명의 중간단계사망이 있어, 10명만이 양방향성 글렌수술을 시행 하였다. 10명의 환자 중 1명의 만기 사망과 1명의 외래 관찰 누락이 있었으며, 6명의 환자는 현재 폰탄 수술을 시행한 후 외래 관찰 중이고, 2명은 폰탄 수술을 위해 대기 중이다. 폰탄 수술 후에는 1명에서 출혈로 재수술을 한 이외의 합병증은 없었다. 모든 환자가 정상 동성 리듬을 보였다. 수술 후 시행한 초음파에서 모든 환자에서 좋은 심실기능을 관찰할 수 있었으며, 삼첨판 역류는 2명에서만 Grade I으로 관찰되었다. 환자들은 현재 평균 $19.6{\pm}14.9$개월(1.5~39.1개월)간 외래 관찰 중이며, 현재 모든 환자에서 항 혈소판제(아스피린) 및 심장약을 투약하고 있으며, 모두 NYHA functional class I의 상태이다. 결론: 좌심형성부전증후군으로 Norwood 술식을 거쳐 최종적으로 폰탄 수술을 시행한 환자에서 1차 수술 후 높은 사망률을 보임에도 불구하고 만족할만한 혈류역학과 임상상태를 확인할 수 있었고, 단계적 수술 교정법은 이 질환에서, 보다 적극적으로 고려되어야 된다고 사료된다.

• Journal of Chest Surgery
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• 제29권1호
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• pp.86-89
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• 1996

심실중격 결손을 동반한 대 혈관전위 에서 심방교체술(denning Procedure)후에 동맥전환술로 성공적인 치료를 했기에 보고하는 바이다 15개월 남아는 생후 8개월에 심방교체술(Senning operation)을 받은 이후에 심부전의 악화로 입원하였다. 혈관조영술상 우심부전, 삼천판막 폐쇄부전 및 잔류 심실중격 결손이 있었고, 심도자 검사에서 폐동맥심실/(LV/RV) 압력비는 75185여서 Senning (심방교체술)을 해체하고, 심실중격 결손은 포편 (patch)봉합하였으며, 폐동맥 밴딩하지않고 동맥전환술을 시행하였다. 수술후 심실기능이 정상으로 회복되었고 잘지내고 있다.