• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.363-365
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• 1991

This paper presents a method for feeder reconfiguration in order to operate distribution systems efficiently using heuristic rules. The reconfiguration method presented here not only eliminates various abnormal states but also achieves minimum power loss and optimum load balance of the distribution feeders under normal operating condition transfering loads from one feeder to anoter applying the experiences of the experts. To implement the method effectively, a best-first tree searching strategy based on heuristics is used to evaluate the various load transfer alternatives. The development of a rule-based system aimed at the reduction of the search space is presented as a means of implementing the best-first searching strategy. The results of the computer simulation of the above procedure are as follows; 1) achieving minimum power loss of the distribution feeder adopting the optimum load transfer alternative. 2) Enhencing system reliability and achieving load balance through rational allocation of the feeder loads.

• Journal of Chest Surgery
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• 제18권2호
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• pp.320-326
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• 1985

Pulmonary sequestration occurs when some disturbance produces a cystic mass of nonfunctioning lung tissue which lacks normal communication with the tracheobronchial tree. Between 1971 and 1985, pulmonary sequestration was diagnosed in 11 patients, ranging age from 3 to 29 years. All sequestration were intralobar type. Definitive diagnosis can only be obtained by aortography and/or surgical exploration in 10 cases. The other one was confirmed by pathologic examination postoperatively. The presenting complaints were mostly recurrent local pulmonary infection, but in 2 cases mediastinal mass with respiratory symptoms was presented, and cardiac murmur was only finding in one case. Preoperative diagnostic procedure revealed 3 associated anomalies which were funnel chest, right aortic arch, and pulmonic stenosis with vascular ring. Operative treatment for sequestration was lobectomy in 10 cases, and a segmentectomy in one. There was no operative mortality, but 3 complications [empyema, B-P fistula, post-op bleeding] which were controlled by subsequent operations or conservative measure. Aortography is strongly advocated not only for its diagnostic value, but for its preoperative localization of the aberrant vessels that are the major concern to the surgeon.

• 산업공학
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• 제17권2호
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• pp.200-207
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• 2004

Because the designed workflow may contain potential errors which may result in deadlocks, livelocks and so on, it is important to analyze the correctness of a workflow definition before it is put into the run time environment. Proposed in this paper is a transformation procedure of an UML activity diagram into a Petri net for the analysis of a workflow. By combining the strengths of easy-to-use functionality of an activity diagram and the analysis power of a Petri net, workflow analysts in the enterprise can model and analyze various kinds of workflow definition more easily and accurately.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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• pp.111-115
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• 1997

There exists a interface among the different kinds of materials in the solid insulating ones, which effects on the insulating capability heavily. The insulating construction has been developed for each usages and take themselves into several sorts. The conjunction between CV cables have the electrical weakness of solidity and solid interface, so they were focused at the long distance-line. To this background, it is very important to get the information on the interface influencing on the insulating capability of cable and to observe its procedure. In this paper, the interface was made artificially to research the effect owing to the toughness of interface, which results in the aging and treeing proceeding was observed. The polyethylen, as is generally using for the cable, was taken in this research.

• Journal of Ship and Ocean Technology
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• 제4권4호
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• pp.19-33
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• 2000

For the prevention of marine accidents based on human factor, the risk assessment analysis procedure is proposed which consists of (1) the structural analysis of marine accident, (2) the estimation of incidence probability based on the Fault Tree analysis, (3) the prediction of ef-fectiveness to reduced the accident risk by suitable countermeasures in the specified functional system, and (4) the risk assessment by means of minimizing of the total cost expectation and the background risk. As a practical example, the risk assessment analysis for preventing is investigated using the proposed method.

• 전자공학회논문지A
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• 제33A권10호
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• pp.48-60
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• 1996

This paper focuses on the necessities of interworking and dervation of the requirements of interworking system for interworking between 64 Kbps based N-ISDN (narrowband ISDN) and B-ISDN(broadband ISDN). Furthermore, the design and the implementation of IWF (interworking function) are presentd. We analyze two ISDN signalling systems, and propose the architecture of interworking system. And then we make the baisc call procedure model between N-ISDN and B-ISDN, and verify the dynamic behaviors through the reachability tree of petri net. IWF is designed and implemented for transforming the differences between the two signalling systems. The operational confirmity of th eimplemented program was confirmed by the local test method. The performance of IWF was evaluated throguh the simulation language SLAM-II. As the result of evaluation shows, we confirm that the processing delay is maintained within 3 ms under the utilization 0.9.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 1998년도 추계종합학술대회
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• pp.450-455
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• 1998

This paper proposes an enhanced transport protocol for multipeer communications. It is assumed that there exists a transport connection owner that takes the roles of the establishment, management and termination of a transport connection. The proposed protocol classifies the data transfer type into simplex, duplex and N-plex multicasts and provides several transport services to support various requirements in group communications. The general operations and reliability controls of each transfer type are different from one another and carried out by a shared control tree. The QoS negotiation is performed during the creation phase. The notification of negotiated values is followed by an acknowledgment procedure for confirmation. The four-way handshake is introduced. After negotiation, such a resource reservation protocol as RSVP can reserve system and network resources according to the arbitrated values. This paper suggests a conceptual model of the transport layer and its protocol behaviors over the IP multicast and RSVP network.

• Journal of Dental Anesthesia and Pain Medicine
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• 제18권4호
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• pp.267-270
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• 2018

As a safety measure, dentures are routinely removed before surgery. Aspiration of a denture could be catastrophic, with medicolegal implications. Foreign body aspiration is uncommon in adults; however, aspirations may remain asymptomatic and undiagnosed for long periods of time. We report an adult male who presented with a cough for more than 6 months. On radiography, a foreign body was found migrating within the tracheobronchial tree from one mainstem bronchus to the other, at different time points. The foreign body was later found to be a portion of his denture. The aspiration may have occurred at the time of a surgical procedure.

• International Journal of Contents
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• 제2권1호
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• pp.34-38
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• 2006

In this paper, an overview of anti-collision algorithm for RFID system of a standard EPC Class1 protocol is presented, and the binslotted dynamic search algorithm (BDS) based upon the slotted ALOHA and binary tree procedure is proposed and analyzed. Also, the performance is evaluated as comparing the BDS algorithm with the standard bin-slotted algorithm (BSA) through the simulation program. The performance of the proposed BDS algorithm is improved by dynamically identifying the collided-bit position and the collided bins stored in the stack of the reader. As the results, the number of request command that a reader send to tags in the reader s interrogation zone and the total recognition time are decreased to 59% as compared with BSA algorithm. Therefore, the tag identification performance is fairly improved by resolving a collision problem using the proposed BDS algorithm.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2002년도 춘계공동학술대회
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• pp.877-884
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• 2002

This paper deals with a multi-stage TSK fuzzy modeling method by using Genetic Programming (GP). Based on the time sequence of sampling data the best structural change points of complex systems are detemined by using GP, and also the moving window is simultaneously introduced to overcome the excessive amount of calculation during the generating procedure of GP tree. Therefore, a multi-stage TSK fuzzy model that attempts to represent a complex problem by decomposing it into multi-stage sub-problems is addressed and its learning algorithm is proposed based on the Radial Basis Function (RBF) network. This approach allows us to determine the model structure and parameters by stages so that the problems ran be simplified.