• Journal of information and communication convergence engineering
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• v.12 no.1
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• pp.53-59
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• 2014

Motion estimation is a core part of most video compression systems since it directly affects the output video quality and the encoding time. The full search (FS) technique gives the highest visual quality but has the problem of a significant computational load. To solve this problem, we present in this paper a modified median (MMED) operation and advanced search strategies for fast motion estimation. The proposed MMED operation includes a temporally co-located motion vector (MV) to select an appropriate initial candidate. Moreover, we introduce a search procedure that reduces the number of thresholds and simplifies the early termination conditions for the determination of a final MV. The experimental results show that the proposed approach achieves substantial speedup compared with the conventional methods including the motion vector field adaptive search technique (MVFAST) and predictive MVFAST (PMVFAST). The proposed algorithm also improves the PSNR values by increasing the correlation between the MVs, compared with the FS method.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1998.11a
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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 Applied Reliability
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• v.15 no.3
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• pp.170-175
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• 2015

Reliability demonstration tests (RDT's) are widely employed in design verification and process validation stages of industry. New mixed attribute-variable RDT plans that compromise demerits of the corresponding zero and zero or one failure plans which are common in practice are developed for the exponential distribution. The proposed mixed plans are compared with the typical RDT plans in terms of probability of acceptance and expected test termination time. A numerical example is provided to illustrate the mixed plans and a procedure to extend these plans to the Weibull distribution with known shape parameter is also presented.

• Journal of Cerebrovascular and Endovascular Neurosurgery
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• v.25 no.1
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• pp.13-18
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• 2023

Objective: Mechanical thrombectomy (MT) is an effective treatment for patients suffering from acute ischemic stroke secondary to large vessel occlusion. However, recanalization failure rates of interventions were about 20% in literature studies. We report our experience of unsuccessful MT with a focus on technical reasons. Methods: From December 2010 to June 2021, six hundred eight patients with acute ischemic stroke due to large artery occlusion received MT using a stent retriever with or without an aspiration catheter in our institution. We divided the reasons for failure into six categories. We analyzed the reasons for failure by dividing our experience time into 3 periods. Results: A total of 608 cases of thrombectomy for large vessel occlusion were identified in the study period. The successful recanalization rate was 90.4%. In most of the cases (20/57, 35%), the thrombus persisted despite several passes, and the second most common cause was termination of the procedure even after partial recanalization (10/57, 18%). Similar proportions of in-stent occlusion, distal embolization, and termination due to vessel rupture were observed. On analysis of three periods, the successful recanalization rate improved over time. Conclusions: MT fails due to various reasons, and intracranial artery stenosis is the main cause of MT failure. With the development of rescue techniques, the failure rate has gradually decreased. Further development of new devices and techniques could improve the recanalization rates.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.2C
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• pp.160-169
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• 2002

An ATM-PON (Passive Optical Network) system consists of an OLT (Optical Line Termination), multiple ONUs (Optical Network Units) and the optical fiber which has a PON (Passive Optical Network)configuration with a passive optical splitter. To avoid cell collisions on the upstream transmission, an elaborate procedure called as ranging is needed when a new ONU is installed. The ONU can send upstream cells according to the grant provided by the OLT after the procedure. To prevent collisions being generated by the variation of several factors, OLT must performs continuously the cell phase monitoring. It means that the OLT predicts the expected arrival time, monitors the actual arrival time for all upstream cells and calculates the error between the times. Accordingly, TC (Transmission Convergence) chip in the OLT needs a predictor which predicts the time that the cell will arrive for the current grant. In this paper, we implement the predictor by using shift registers of which the length is equivalent to the equalized round trip delay. As each register consists of 8 bit, OLT can identify which ONU sends what type of cell (ranging cell, user cell, idle cell, and mini-slot). Also, TC chip is designed to calculate the effective bandwidth for all ONUs by using the function of predictor. With the time simulation and the measurement of an implemented optical board, we verify the operation of the predictor.

• Korean Security Journal
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• no.13
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• pp.47-70
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• 2007

The criminal procedure is based upon two ideal values, or 'speedy trial and economy of litigation' and 'finding truth and guarantee of human rights', which are conflicting each other. The so called summary trial system, a simplified procedure through which a judge handles clearly obvious and minor offences in a quick and efficient manner, has its essential purpose of termination lawsuits promptly and freeing suspects or defendants from criminal procedure at the earliest possible moment. But its excessive emphasis on this purport is very likely to result in insufficient examination and inadequate protection of suspects' or defendants' rights. Therefore, the summary trial system needs a variety of safeguards to prevent these feasible - but undesirable - effects. From this point of view, we should objectively review the current summary trial system. The main object of this study is to investigate what problems the system has both in institution and in practice, and to suggest legal measures, including the abolition of it, to improve the simplified procedure. In conclusion, the summary trial system should be maintained because it has still more merits than faults. And these defects will be able to be overcome by reform measures ; for example, the introduction of the right to opt between the summary procedure and the formal trial, the abolition of detention and so on.

• The Korean Journal of Franchise Management
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• v.8 no.3
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• pp.29-37
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• 2017

Purpose - In recent years, research has been conducted on the conflict resolution strategies of the franchise headquarters and the franchisees, but there is a lack of research on the factors of conflict due to the intrinsic structure, such as interdependence or hierarchical relationship, and behavioral analysis to reduce the conflict. In this study, we analyze the relationship between satisfaction and trust formed in the process and result of the business, and the result of action to dissolution intention. Research design, data, methodology - For these purposes, the author developed the proposed model and several hypotheses. In this model, conflict resolution strategies consist of five dimensions such as avoiding, forcing, cooperating, obliging, and compromising strategy. And, this model proposed that onflict resolution strategies are antecedents of procedure quality, behaviour quality and dissolution intention are consequences of conflict resolution strategies. The data were collected from April 1 to April 15, 2013. Because this study examined franchise industries from the franchisee perspective, we contacted franchisee store owner and managers located in Seoul and Gyeonggi Province. Interviewers trained contacted a total of 483 franchisees, and 400 franchisees responded. Out of 400 respondents, 2 respondents were deleted due to missing information. Thus, a total of 398 franchisee were used for this study. he data were analyzed using frequency analysis, confirmatory factor analysis, correlation analysis, and structural equational modeling with SPSS 24.0 and Amos 23.0 statistical program. Results - The findings can be summarized as follows: First, franchisor conflict resolution activities have significant effects on procedure quality. Second, procedure quality has a significant effect on behavior quality. Finally, behavior quality has a significant effect on dissolution intention. Conclusions - In this study, we investigated the relationship between conflict resolution behavior, procedural quality, behavior quality and dissolution intention. As a result, the franchisers should strive to resolve conflicts not only in solving simple problems with franchisees, but also in a longer term perspective. We also found that the procedural aspects of resolving conflicts should not be ignored. If the trust and satisfaction of each other increase during the process of resolving the conflict, it will positively affect the satisfaction and trust in resolving the conflict. This is also because it serves to lower the intention of termination. However, there is a limitation that it is targeted only to the restaurant franchise, and it is necessary to study the conflict resolution behavior depending on the type of conflict.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.38 no.4
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• pp.307-315
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• 1989

In this paper, we have analyzed the temperature variation trend of a slab on between the process of reheating furnace and the termination of roughing mill process during hot rolling process. 1) cooling by radiation and convection current in the air, 2) plastic deformation heat, 3) cooling by descaling water, 4) cooling by contact with rolling rolls and/or transmitting rolls. For the analysis, the factors have been adopted as the problems of the rolling process to be solved such that we have established an application technique in relation to the determination of boundary conditions on the slab surface. We have presented a procedure for an analysis of the cooling phenomenon treated as a problem of two-dimensional transient heat flow using finite difference equation and suggested techniques of implementing sequentialized rolling tasks in correlation with the procedure. From the result of simulation, it is shown that the difference between calculation value and measurement value is within the range of the industrial measurement error. Also, it is proved that the assumptions, conditions, and properties used in the computer simulation is appropriate by showing that the pattern of a drop in temperature at each rolling event is in accord with real circumstances.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.361-361
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• 2009

KEPCO High Temperature Superconducting (HTS) cable system rated with $3\Phi$, 22.9kV, 1250A was laid in 2006, and the long term test is in progress. The HTS cable system with the cooling system has been operated below cryogenic temperature. That environment exposes the system to the thermo-mechanical stress due to the significant temperature difference, and the cooling system has moving parts for the forced circulation of the coolant. Therefore the HTS cable system experiences thermal fatigue and moving part such as liquid nitrogen pump need a regular replacement every 5000 hours Building the assessment criterion, the maintenance procedure was established and regular preventive maintenance was done; improvement of the termination structure and the replacement of the bearing of liquid nitrogen pump. Following the proper process, the reliability assessment test including He leakage detection and the stability of flow rate was performed. This paper describes the process and result of the first regular maintenance of KEPCO HTS cable system

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.10
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• pp.1183-1192
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• 1988

In this paper, we describe heuristic information-added morphological dictionary and connection table, and automatic MUNJEUL separation process on the basis of least cost method for efficient morphological analysis. It is simplified the composition of connection and inflective word information by mutually interconnect conjugation table with connection tables. As a result, the applicability of system is increased. Translation dictionary consists of analysis and generation part and, increase the applicability by describing frequently using termination phrase which is extracted statistically as idiom and the procedure directly on the dictionary for the efficiency of analysis process and more natural generation of translation sentence.