• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.453-454
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• 2008

Modern VLSI designs get increasingly complex and time-to-market constraints get tighter. Using high level languages is one of the most promising solutions for improving design productivity by raising the level of abstraction. In high level synthesis process, most important step is scheduling. In this paper, we propose fast and efficient scheduling method under timing constraint based on list scheduling. Experimental results on well known data path intensive designs show fast execution times (less than 0.5 sec) and similar results when compared to optimal solutions [1].

• IEIE Transactions on Smart Processing and Computing
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• v.2 no.1
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• pp.1-10
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• 2013

In JPEG2000, the Cohen-Daubechies-Feauveau (CDF) 9/7-tap wavelet filter is implemented using the conventional lifting scheme. On the other hand, this wavelet filter has two problems: the filter coefficients remain complex, and the conventional lifting scheme does not consider the image edges in the coding process. This paper proposes an effective lifting scheme to solve these problems. For this purpose, optimal 9/7-tap wavelet filters were designed in two steps. In the first step, the appropriate filter coefficients were selected. In the second step, a median operator was employed to consider the image edges. The experimental results with the median lifting scheme and the combination of filter optimization with the median lifting show that the proposed methods outperform the well-known CDF 9/7-tap wavelet filter of JPEG2000 on the edge-dominant images.

• 유체기계공업학회:학술대회논문집
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• 2000.12a
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• pp.187-192
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• 2000

The effects of diffuser shapes on the flowfields of a small-size turbo-compressor have been investigated by numerically and experimentally. It is important to optimal design of each elements for developing the small-size turbo-compressor Typical range of rotating speed of a small-size turbo-compressor is 40,000-70,000rpm. Numerical analyses are conducted to the rectangular and conical shapes of diffusers. Three-dimensional, steady, viscous governing equations are solved by SIMPLE algorithm. To prove the numerical results, experimental studies for the measurements of static pressure and temperature at the inlet and outlet boundaries are performed. Comparisons of these results are executed, and reasonable agreements are acquired.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.103.3-103
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• 2001

Recently Electro active polymer has been discussed in various researches as new actuators replacing the human muscles. Since they have confronted a limitation of more advanced application with traditional actuator. IPMC (Ion exchange Polymer Metal Composite) is one of candidate materials for new actuators. In this paper, we propose a new approach and design principle for the IPMC polymer actuator to conquer the weaknesses of IPMC that is intrinsic weak structural stiffness and low trust forces. In the first we performs some experimental works about how the basic specific characteristics of IPMC vary and what the optimal operating conditions are. And we have applied IPMC as active cilium for realization of annelida motion like ...

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.161.5-161
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• 2001

Robots are required to assist our activities in daily life. In this paper, we focus on arm movement to catch moving object as one of important tasks frequently performed by human. We propose an algorithm which enables a robot to perform human-like arm motion to catch a moving object. First we analyze human hand trajectories and velocity profiles to catch an object. From the experimental results, we extract some characteristics in the process of approaching and following a moving object and confirm that these are necessary to realize human-like motion. We then adopt an instantaneous optimal control method which evaluates the error and energy cost at each sampling step, and design two time-varying weight matrices to introduce human characteristic into robot motion. The matrix concerning the error is defined as a time-increasing ...

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1153-1156
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• 2003

In this paper, we present a reducing power consumption of a scheduling for module selection under the time constraint. Traditional high-level synthesis do not allow reuse of complex, realistic datapath component during the task of scheduling. On the other hand, the proposed scheduling of reducing power consumption is able to approach a productivity of the design the low power to reuse which given a library of user-defined datapath component and to share of resource sharing on the switching activity in a shared resource. Also, we are obtainable the optimal the scheduling result in experimental results of our approach various HLS benchmark environment using chaining and multi-cycling in the scheduling techniques..

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.5
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• pp.149-157
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• 1994

This paper Presents an algorithm for synthesis of sequential statements described at RT level VHDL. The proposed algorithm transforms sequential statements in VHDL into data-flow description consisting of concurrent statements by local and global dependency analysis and output dependency elimination. Transformation into concurrent statements makes it possible to reduce the cost of the synthesized hardwares, thus to get optimal synthesis results that will befit the designer 's intention. This algorithm has been implemented on VSYN and experimental results show that more compact gate-level hardwares are generated compared with Power View system from ViewLogic and Design Analyzer from Synopsys.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.10a
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• pp.78-82
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• 2004

The co-cured joint has been widely used in joining process of composite structures due to its simple and easy manufacturing process. In this paper, the effect of stacking sequence of the carbon epoxy prepreg, bonding length and thickness of the aluminum plate on the static tensile load capability of the co-cured aluminum-composite double lap joint were experimentally investigated. From experimental results, the optimum EA ratios with respect to stacking sequence and bonding length of the co-cured joint were obtained, which may be useful for the joining of hybrid structures.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.7
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• pp.1003-1011
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• 2009

This study aims at precise control of oil outlet temperature in the oil cooler system of machine tools for enhancement of working speed and processing accuracy. PID control logic is adopted to obtain desired oil outlet temperature of the oil cooler system with hot-gas bypass method. We showed that the gains of PID controller could be easily determined by using gain tuning methods to get the gain of PID controller without any mathematical model. We also investigated various gain tuning methods to design the gains of PID and compared each control performance for selecting the optimal tuning method on the hot gas bypass method through experiments. Moreover, we confirmed excellent control performance with proposed PI controller gain even though disturbances were abruptly added to the experimental system.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.1
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• pp.12-18
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• 2008

This paper describes two run-to-run controllers, a nonlinear multiple exponential-weight moving-average (NMEWMA) controller and a dynamic model-tuning minimum-variance (DMTMV) controller, for photolithography processes. The relationships between the input recipes (exposure dose and focus) and output variables (critical dimensions) were formed using an experimental design method, and the photolithography process model was built using a multiple regression analysis. Both the NMEWMA and DMTMV controllers could update the process model and obtain the optimal recipes for the next run. Quantified improvements were obtained from simulations and real photolithography processes.