• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.1B
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• pp.86-100
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• 2004

To provide the end-to-end service differentiation for assured services, the random early demotion and promotion (REDP) marker in the edge router at each domain boundary monitors the aggregate flow of the incoming in-profile packets and demotes in-profile packets or promotes the previously demoted in-profile packets at the aggregate flow level according to the negotiated interdomain service level agreement (SLA). The REDP marker achieves UDP fairness in demoting and promoting packets through random and early marking decisions on packets. But, TCP fairness of the REDP marker is not obvious as for UDP sources. In this paper, to improve TCP fairness of the REDP marker, we propose a modified REDP marker where we combine a dropper, meters and a token filling rate configuration component with the REDP marker. To make packet transmission rates of TCP flows more fair, at the aggregate flow level the combined dropper drops incoming excessive in-profile packets randomly with a constant probability when the token level in the leaky bucket stays in demotion region without incoming demoted in-profile packets. Considering the case where the token level cannot stay in demotion region without the prior demotion, we propose a token filling rate configuration method using traffic meters. By using the token filling rate configuration method, the modified REDP marker newly configures a token filling rate which is less than the negotiated rate determined by interdomain SLA and larger than the current input aggregate in-profile traffic rate. Then, with the newly configured token filling rate, the token level in the modified REDP marker can stay in demotion region pertinently fir the operation of the dropper to improve TCP fairness. We experiment with the modified REDP marker using ns2 simulator fur TCP sources at the general case where the token level cannot stay in demotion region without the prior demotion at the negotiated rate set as the bottleneck link bandwidth. The simulation results demonstrate that through the combined dropper with the newly configured token filling rate, the modified REDP marker also increases both aggregate in-profile throughput and link utilization in addition to TCP fairness improvement compared to the REDP marker.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.14 no.2
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• pp.122-129
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• 2014

Effective information gathering and retrieval of the most relevant web documents on the topic of interest is difficult due to the large amount of information that exists in various formats. Current information gathering and retrieval techniques are unable to exploit semantic knowledge within documents in the "big data" environment; therefore, they cannot provide precise answers to specific questions. Existing commercial big data analytic platforms are restricted to a single data type; moreover, different big data analytic platforms are effective at processing different data types. Therefore, the development of a common big data platform that is suitable for efficiently processing various data types is needed. Furthermore, users often possess more than one intelligent device. It is therefore important to find an efficient preference profile construction approach to record the user context and personalized applications. In this way, user needs can be tailored according to the user's dynamic interests by tracking all devices owned by the user.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.801-803
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• 2004

The current drive in an MOSFET is limited by the intrinsic channel resistance. All the other parasitic elements in a device structure playa significant role and degrade the device performance. These other resistances need to be less than $10{\%}-20{\%}$ of the channel resistance. To achieve the requirements, we should investigate the methodology of separation and quantification of those resistances. In this paper, we developed the extraction method of resistances using calibrated TCAD simulation. The resistance of the extension region is also partially determined by the formation of a surface accumulation region that forms under the gate in the tail region of the extension profile. This resistance is strongly affected by the abruptness of the extension profile because the steeper the profile is, the shorter this accumulation region will be.

• Proceedings of the KIPE Conference
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• 2003.07a
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• pp.247-250
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• 2003

The current paper presents the design and implementation of a low-profile dc-to-dc converter developed as a power supply for the sustain driving: circuit inside large-area wall-mount ac PDP application systems. Details on the design and implementation of a 500 W prototype dc-to-dc converter, miniaturized within a 230 mm$\times$ 130 mm area with a thickness of 25 mm while still achieving a 95 $\%$ conversion efficiency, are presented to demonstrate the feasibility and application potentials of the proposed low-profile dc -to-dc converters.

• Transactions of Materials Processing
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• v.25 no.1
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• pp.61-66
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• 2016

In the current study, we present a new model for the prediction of the strip profile and the residual stresses. This new approach is an analytical model that predicts the residual stresses from the effect of post-deformation. Since the residual stress cannot exceed the yield strength of the material, post-yielding may possibly occur in the post-deformation zone prior to the strip reaching the steady-state zone. The prediction accuracy of the proposed model is examined through comparison with the predictions from 3-D finite element (FE) simulations.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.333-336
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• 2003

The current paper presents the design and implementation of a low-profile dc-to-dc converter developed as a power supply for the sustain driving circuit inside large-area wall-mount ac PDP application systems. Details on the design and implementation of a 500 W prototype dc-to-dc converter, miniaturized within a 230 $mm{\times}130$ mm area with a thickness of 25 mm while still achieving a 95 % conversion efficiency, are presented to demonstrate the feasibility and application potentials of the proposed low-profile dc-to-dc converter.

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.2
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• pp.49-53
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• 2005

The current drive in a MOSFET is limited by the intrinsic channel resistance. All other parasitic elements in a device structure perform significant functions leading to degradation in the device performance. These other resistances must be less than 10$\%$-20$\%$ of the channel resistance. To meet the necessary requirements, the methodology of separation and quantification of those resistances should be investigated. In this paper, we developed an extraction method for the resistances using calibrated TCAD simulation. The resistance of the extension region is also partially determined by the formation of a surface accumulation region that gathers below the gate in the tail region of the extension profile. This resistance is strongly affected by the abruptness of the extension profile because the steeper the profile is, the shorter this accumulation region will be.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.8
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• pp.84-90
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• 2010

In focused ion beam (FIB) fabrication processes the ion beam intensity with Gaussian profile has a drawback for high resolution machining. In this paper, the fabrication method to modify the beam profile at substrate using silt mask is proposed to increase the machining resolution at high current. Slit mask is utilized to block the part of beam and transmit only high intensity portion. A nano manipulator is utilized to handle the silt mask. Geometrical analysis on fabricated profile through silt mask was conducted. By utilizing proposed method, improvement of machining resolution was achieved.

• Journal of Power System Engineering
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• v.14 no.3
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• pp.64-70
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• 2010

In this study, designing of precise linear transferring device which can be applied to industrial machine and robot industry has been introduced. The direction of power flow and output feature are similar to current Rack-Pinion type. However, unlimited length extensity via rack modulizing, and securing high velocity transportation have been realized by applying Pin-Pinion Gear type at the operation part. The analysis has been calculated to obtain the Pin-Pinion Gear's optimized tooth profile. As a result of research, it is impossible to control precisely even overlap at the teeth of involute and sprocket. Because they have peculiar gearing structure. Therefore, modified cycloid tooth has been proposed to perform high velocity, precise control without backlash.

• Journal of Welding and Joining
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• v.17 no.6
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• pp.46-52
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• 1999

The auxiliary gas-shielded MAG (AMAG) process, which was devised to provide an argon-rich shielding environment using small amount of argon gas, was investigated experimentally to figure out its effects on metal transfer and weld quality. Proper conditions for the AMAG process including the argon gas ratio, position and direction of the auxiliary nozzle were determined experimentally. Performance of the AMAG process was compared with that of the double gas-shielded MAG(DMAG) and MAG processes by monitoring the bead profile, current and voltage waveforms. The AMAG process was found to provide better bead profile, more stable arc and wider operating range of spray transfer mode compared with the DMAG process. In general, performance of the AMAG process using the argon ratio of 30% was comparable to that of the MAG process using 80% argon and 20% CO₂ gas.