• Journal of the Institute of Electronics Engineers of Korea SC
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• v.49 no.4
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• pp.17-22
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• 2012

Convolution filtering methods have been widely applied to various digital signal processing fields for image blurring, sharpening, edge detection, and noise reduction, etc. According to their application purpose, the filter mask size or shape and the mask value are selected in advance, and the designed filter is applied to input image for the convolution processing. In this paper, we proposed an image processing acceleration method for the convolution processing by using two-dimensional Look-up table (LUT) and overlap-region buffering technique. First, based on the fixed convolution mask value, the multiplication operation between 8 or 10 bit pixel values of the input image and the filter mask values is performed a priori, and the results memorized in LUT are referred during the convolution process. Second, based on symmetric structural characteristics of the convolution filters, inherent duplicated operation region is analysed, and the saved operation results in one step before in the predefined memory buffer is recalled and reused in current operation step. Through this buffering, unnecessary repeated filter operation on the same regions is minimized in sequential manner. As the proposed algorithms minimize the computational amount needed for the convolution operation, they work well under the operation environments utilizing embedded systems with limited computational resources or the environments of utilizing general personnel computers. A series of experiments under various situations verifies the effectiveness and usefulness of the proposed methods.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.4
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• pp.430-439
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• 2011

In this paper, we design a digital predistortion(DPD) for linearity enhancement of RF power amplifier operating in 900 MHz band. We verify improvement of linearity by comparing the proposed DPD using tanh as a nonlinear indexing function and the DPD using linear indexing function based on signal amplitude. The digital predistortion is realized by look-up table(LUT) method, and the Saleh model is employed for power amplifier modeling, then a commercial power amplifier module is used for measurement. The LUT has 256 tables, and the NLMS(Normalized Least Mean Square) algorithm was utilized for an adaptive algorithm for estimation. As a result, we improve the ACLR(Adjacent Channel Leakage Ratio) by around 15 dB.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.4 s.175
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• pp.848-857
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• 2000

A pick-and-place operation in 3-dimensional environment is basic operation for human and multi-purpose manipulators. However, there may be a difficult problem for such manipulators. Especially, if the object cannot be moved with a single grasp, regrasping, which can be a time-consuming process, should be carried out. Regrasping, given initial and final pose of the target object, is a construction of sequential transition of object poses that are compatible with two poses in the point of grasp configuration. This paper presents a novel approach for solving regrasp problem. The approach consists of a preprocessing and a planning stage. Preprocessing, which is done only once for a given robot, generates a look-up table which has information of kinematically feasible task space of end-effector through all the workspace. Then, using the table planning automatically determines possible intermediate location, pose and regrasp sequence leading from the pick-up to put-down grasp. Experiments show that the presented is complete in the total workspace. The regrasp planner was combined with existing path.

• Journal of the Korean Graphic Arts Communication Society
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• v.18 no.1
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• pp.35-45
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• 2000

Recently, as the prepress mainstream is changed to the digital workflow, various digital proofing systems such as high price dye sublimation printers and low price ink jet printers are widely used in printing industry. However, most of the digital proofing devices have lower resolution than analog proofing systems and differ with actual color presses in the color gamuts. Therefore, proper color compensations are needed for digital color proofing in order to match colors between the proofs and the press sheets. This study shows the application method of Look-up Table to the digital color proofer of Rainbow, the analog proofer of Matchprint-II, and an actual offset press is effective on the color compensations.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.828-831
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• 1997

One of the most important design factor for the image tracker is the speed of the data processing which allows real-time operation of the system and provides reasonably accurate performance at the same time. Use of powerful DSP alone does not guarantee to meet such requirement. In this paper, a simple efficient algorithm for real-time multi-target image tracking is suggested. The suggested method is based on a recursive centroiding technique and color table look-up. This method has been successfully implemented in a image processing system for Micro-Robot Soccer Tournament(MIROSOT). This tracker can track positions of a ball, 3 enemies, and 3 agents at the same time. The experimental results show that the processing time for each frame of image is less than 7ms, which is well within the 60Hz sampling interval for real-time operation.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.3
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• pp.391-397
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• 2018

This paper proposes a interpolation error compensation method for PMSM torque control. In PMSM torque control, two dimensions look-up table(2D-LUT) is used for current reference generation due to its stable and robust torque control performance. However, the stored data in 2D-LUT is discreet, it is impossible to store all over the operation range. To reduce the reference generation error in this region, the 2D-Interpolation method is conventionally used, however, this method still remains the error affected by the number of stored data. Besides, in the case stored by fixed unit, this error is increased in field weakening region because of the small number of stored data. In this paper, analyzing the cause of this interpolation error, and compensating the method to reduce this error. Proposed method is verified by the simulation and experiment.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.596-700
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• 1998

Nowadays, with increasing many vehicles on restricted roads, the conventional traffic light creates prove startup-delaytime and end-lag-time. The conventional traffic light loses the function of optimal cycle. And so, 30∼45% of conventional traffic cycle is not matched to the present traffic cycle. In this paper proposes electrosensitive traffic light using fuzzy look up table method which will reduce the average vehicle waiting time and improve average vehicle speed. Computer simulation results prove that reducing the average vehicle waiting time which proposed considering passing vehicle length for optimal traffic cycle is better than fixed signal method which doesn't consider vehicle length.

• Journal of Broadcast Engineering
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• v.14 no.4
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• pp.501-508
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• 2009

This paper proposes an efficient transform-domain noise reduction scheme in an H.264 video encoder, where the generalized Wiener filtering is performed in a quantization process by multiplying each transform block with its adaptive multiplication factor. In practice, the computational complexity of the proposed scheme is negligible by replacing the multiplication operation with a simple look-up table method. Also, experimental results show that the proposed scheme provides outstanding noise reduction performance in an H.264 video encoder.

• Proceedings of the Korean Printing Society Conference
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• 2000.12b
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• pp.17-28
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• 2000

Recently, as the prepress mainstream is changed to the digital workflow, various digital proofing systems such as high price dye sublimation printers and low price ink jet printers are widely used in printing industry. However, most of the digital proofing devices have lower resolutions than analog proofing systems and differ with actual color presses in the color gamuts. Therefore, proper color compensations are needed for digital color proofing in order to match color between the proofs and the press sheets. In this paper, we used 3-dimensional look-up table(LUT) and tetrahedral interpolation method for the color space conversion between the device independent color space(CIEXYZ or Lab) and the device dependent color space(CMY) to reduce the color differences between the original copy and digital color proofs and the press sheets.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.852-856
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• 2005

This paper proposes a new design of the ECG simulator with high resolution by using small amount of memories based on discrete least square estimation equations instead of reading the stored data inside the look-up table. The experimental results have shown that the ECG simulator using discrete least square estimation equations can display the bipolar limb leads ECG signals with low PRD (percent root-mean-square difference) while taking the less amount of memories than the previous method which used the look-up table to store ECG data for ECG simulation.