• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.528-531
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• 2004

This paper presents the design and implementation of a QoS based IrDA in mobile phones. The IrDA standards have arised from the need to connect various mobile devices together. But currently, we have a difficult to connecting various mobile devices together. The difficult thing is to adjust the minimum turn around time. The minimum turn around time in IrDA deals with the time needed for a receiver circuit to recover following saturation by transmissions from the same device (turn around latency). This parameter corresponds to the required time delay between the last byte of the last frames sent by a station and the point at which it is ready the first byte of a frame from another station. This parameter comes into play when the link is turned around and is negotiated independency for each station. We solve this matter by using the Dynamic Adjustment Algorithm (DAA). The dynamic adjustment algorithm adjusts the minimum turn around time according to the numbers of devices. We apply our direct adjustment algorithm to our QoS based IrDA in mobile phones and show the improved performance of connection with various mobile phones together.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.5
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• pp.473-478
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• 2016

In this paper, the MIS(: Metal-Insulator-Semiconductor) Capacitor with the nitrided-oxide by RTP are fabricated to investigate the carrier trap parameters due to avalanche electron injection. Two times turn-around phenomenon of the flatband voltage shift generated by the avalanche injection are observed. This shows that electron trapping occurs in the oxide film at the first stage. As the electron injection increases, the first turn-around occures due to a positive charge in the oxide layer. After further injection, the curves turns around once again by electron captured. Based on the experimental results, the carrier trapping model for system having multi-traps is proposed and is fitting with experimental data in order to determine trap parameter of nitrided-oxide.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.792-798
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• 2008

Supply chain management (SCM) has been drawn increasing attention in industries and academia. The attention is mainly due to a need to integrate the multiple activities in a process network from the overall perspective under the constantly varying economic environment. While many researchers have been addressing various issues of SCM, there is not much research explicitly handling the overall dynamics of supply chain entities from PSE literature. In this two-part series paper, it is investigated how the overall supply chain processing times vary in response to the variation of individual entities using Monte Carlo simulation. Instead of figuring out the operation levels of individual entities, the overall operation time called TAT(Turn-Around-Time) is proposed as a performance indicator. An example of 7 entity-supply chain is presented to illustrate the proposed methodology.

• Nuclear Engineering and Technology
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• v.24 no.3
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• pp.297-310
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• 1992

FLECHT SEASET unblocked forced reflood tests are assessed using Apollo version of RELAP5/MOD3 5M5. The main purpose of the study is to examine the code predictability under forced reflood conditions having different initial power levels and flooding rates. Among various test matrices, the assessment calculations are performed for the test numbers 31701 31302, 31203, 31805, 34524, 31021, 34006 and 35807 These have been selected because they have similar initial conditions but different initial peak rod powers or flooding rates. In addition, various sensitivity calculations are performed for test number 31203 on the improved models of RELAP5/MOD3. Those are for the effect of Counter Current Flow Limit (CCFL) option at the outlet junction of the test section, for the effect of grid modelling on the interfacial drag calculations as well as on the heat structure calculations, and for the effect of nodalization and the time step size. The results of sensitivity studies show that the improved models of RELAP5/MOD3 enhance the code predictability. The assessment results show that the RELAP5/MOD3 has a tendency to underpredict the turn around temperature and the turn around time. But RELAP5/MOD3 silghtly overpredicts the turn around temperature for high flooding rate. The results also show that the calculated quenching by RELAP5/MOD3 is delayed with the increase of the rod power or the decrease of the flooding rate.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.8
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• pp.1356-1361
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• 2008

A switched reluctance generator(SRG) has simple magnetic structure, and needs simple power electronic driving circuit. But, a SRG are no windings or permanent magnets on the rotor, and there are concentrated windings placed around each salient pole on the stator. Because of the characteristics of time-sharing excitation, the control of SRG is very flexible. And there are several parameters for controlling SRG, such as switch turn-on angle, switch turn-off angle, and exciting voltage and controlling mode, all these will affect the generation greatly. A SRG has positive torque at increasing inductance region and negative torque at decreasing inductance region. In this paper, we studied characteristics about the switch turn-on and off angles according to switch method for constant output voltage of the fixed speed SRG. It is the acoustic noise and torque ripple characteristics. Characteristics for a switch angle and method are presented by experiment using a 50W SRG with 12/8 poles.

• Electrical & Electronic Materials
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• v.6 no.2
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• pp.115-120
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• 1993

본 연구에서는 dry oxide와 wet oxide로 MOS capacitor를 제작하여 avalanche 전자주입 실험으로 산화막의 캐리어 트랩핑특성을 조사하였다. dry oxide에서는 avalanche 전자주입 시 전자 trapping이 주도적으로 일어났다. wet oxide에서는 주입 초기에 전자 trapping이 주도적이다가 hole trapping이 주도적으로 바뀌게 되는 turn-around 현상이 일어났다. 주입시간이 길어지면 다시 전자 trapping이 주도적으로 되는 또 한번의 turn-around 현상이 일어났다. 산화막의 트랩 parameter를 결정하기 위해 실험결과를 기초로 하여 종류가 다른 여러 트랩을 가지는 계에 대한 캐리어 트랩핑 이론식을 세워서 실험결과와 curve-fitting한 결과 실험치와 잘 일치하는 곡선을 얻었다.

• Trans-
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• v.10
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• pp.1-13
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• 2021

If virtual reality is well known through the medias, it seems that a few visual concepts are clearly related to VR. We try to think about it and introduce to a philosophy of VR techniques. So, from techniques and media techno-powers promotional campaigns, we aim to areal technology, it means an objective reflection on the VR techniques. To do so, we study the representations of VR in films. And we conclude that a negative image is the most common representation, related, often, to an Orwellian vision of the future world. In the second part, we study some VR films, and especially some made by famous film directors (Iñárritu, Bigelow). 'Head-turn' and 'Walk-around' films are commented to check their limits. Finally, we consider that for the moment, VR remains only a new space to screen films (into VR platforms connected to the Internet).

• Proceedings of the Korea Society of Costume Conference
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• 2001.10a
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• pp.81-81
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• 2001

• Korea Journal of Hospital Management
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• v.19 no.3
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• pp.1-10
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• 2014

The purpose of this study was to present base data for an efficient management of medical expenses at the hospital management by doing grasp of status of medical expenses from seamen's insurance by voluntary agreements. A Object of study is analyzing the data of medical expenses occurred from the total number of 2,699(inpatients 507, outpatients 2,192)cases who were covered by seamen's insurance at a general hospital which is located in Pusan Metropolitan City during 48 months from January 1, 2009 to Dec 31, 2012. The main results of this study are as follows: accrual medical expenses are the ship management companies member of P&I insurance is the most highest but share of receivables are the Korean ocean-going companies member of P&I insurance is the most highest, therefore, Korean ocean-going companies focus strictly than the payments from accounts receivable management should be considered to reduce the occurrence and concerning the turn around period of medical receivables are 4 months to 6 months during a research period. Therefore, it will be needed for managers of hospitals to prepare differentiated management based on the characteristics of each in insurer and to have recovery strategies of uncollected medical expenses.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.2
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• pp.143-150
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• 2007

Ring and cylinder bore wear may not be a problem in most current automotive engines. However, a small change in ring face and cylinder bore diameter can significantly affect the lubrication characteristics and ring axial motion. This in turn can cause to change inter-ring pressure, blow-by and oil consumption in an engine. Therefore, by predicting the wear of piston ring face and cylinder bore altogether, the changed ring end gap and the changed volume of gas reservoir can be calculated. Then the excessive oil consumption can be predicted. Here, the oil amount through top ring gap into combustion chamber is estimated as engine oil consumption. Furthermore, the wear theories of ring and cylinder bore are included. The changed oil consumption caused by the new end gap and the new volume of oil reservoir around second land, can be calculated at some engine running interval. Meanwhile, the wear amount and oil consumption occurred during engine durability cycle are compared with the calculated values. The wear data of rings and cylinder bore are obtained from three engines after engine durability test. The calculated wear data of each part are turn out to be around the band of averaged test values or a little below. It is shown that the important factor regarding oil consumption increasement is the wear of ring face.