• Nuclear Engineering and Technology
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• v.44 no.4
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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.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.4
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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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• v.23 no.5
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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.

• Proceedings of the KSRS Conference
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• 2005.10a
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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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• v.26 no.5
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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.

• Proceedings of the IEEK Conference
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• 2001.06a
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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.

• IE interfaces
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• v.21 no.1
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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.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.14 no.1
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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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• v.42 no.1
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• pp.9-13
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• 2009

Background: Hypoplastic left heart syndrome is uniformly fatal if this condition is not properly treated. We reviewed the surgical results of treating hypoplastic left heart syndrome, and we evaluated the hemodynamics and functional status of these patients after they underwent a Fontan operation. Material and Method: To assess the surgical results, we retrospectively reviewed the medical records of 6 (M/F=4/2) patients who underwent a staged operation, including a Norwood procedure, a bidirectional Glenn procedure and a Fontan procedure between October 1997 to May 2005. The mean age of the patients was $17.3{\pm}10.8$ days (range: 9~36 days) at the $1^{st}$ staged operation, $8.9{\pm}7.1$ months (4.6~23.3 months) at the $2^{nd}$ staged operation (the Bidirectional Glenn procedure) and $32.4{\pm}9.8$ months at the final staged operation (the Fontan procedure). During the $2^{nd}$ staged operation, one of the patients received tricuspid valve repair due to regurgitation. All the patients underwent an extracardiac Fontan procedure using Gore-Tex conduit (20 mm: 2 patients, 18 mm: 4 patients) and one of them required fenestration. Result: 21 patients underwented a Norwood procedure. There were 7 early deaths and 4 interstage deaths. Bidirectional cavopulmonary shunt was performed in 10 patients and the Fontan procedure was done in 6 (mortality: 1 patient, Flow up loss: 1 patient, Awaiting a Fontan procedure: 2 patients). After the Fontan procedure, there was no complication except for one case of post operative bleedings. All the patients had good ventricular function and 2 had grade I tricuspid regurgitation, as noted on their echocardiography. The average follow up period after the Fontan procedure was $19.6{\pm}14.9$ months (range: 1.5~39.1 month). All the patients had normal sinus rhythm and they were put on aspirin and cardiac medication. During follow up period, all the patients had a good functional status (NYHA functional class I). Conclusion: All the patients who suffered with hypoplastic left heart syndrome and who underwent a Fontan procedure achieved a good hemodynamic and functional status, even though there was a relatively high operative mortality rate after stage I Norwood palliation. Therefore, thise staged operation should be strongly recommended as an important surgical strategy for treating hypoplastic left heart syndrome.

• 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.