• Proceedings of the KIPE Conference
• /
• 2013.07a
• /
• pp.108-109
• /
• 2013

본 논문에서는 PMSM 제어를 위한 Look-up Table 사용시 적용되는 인터폴레이션 개선기법에 대하여 설명한다. PMSM은 약계자 영역에서 속도 증가에 따라 전류제한원의 영향에 의해 q축 전류가 감소하는 운전을 하게 된다. 기존의 PMSM 약계자 영역에서는 Look-up Table을 이용한 제어시 d,q축 전류 데이터 부족에 의해 선형 인터폴레이션 구간이 늘어나기 때문에 지령과 실제 전류에 오차가 발생하게 된다. 본 논문에서는 약계자 영역에서 q축 전류 보상기를 통해 선형 인터폴레이션에 의해 발생하는 오차를 보상하는 전류제어 방법에 대하여 제안한다.

• Journal of Information Display
• /
• v.2 no.2
• /
• pp.32-38
• /
• 2001

PDP(plasma display panel) represents the gray levels by the pulse number modulation technique that results in undesirable dynamic false contours on moving images. This paper proposes a LUT(Look-up table) based error diffusion algorithm for reduction of the dynamic false contours. A quantitative measure of the dynamic false contours is defined first. The measure of the dynamic false contours is calculated through simulation of every gray level combination of two consecutive frames. Based on the calculated measures, a modified gray level for a pair of gray levels of two consecutive frames is chosen to reduce the dynamic false contours. The chosen gray levels serve as contents of a gray level conversion LUT. Given a pair of gray levels of two consecutive frames, the gray level of current frame is modified based on the gray level conversion LUT. The new gray level is displayed on PDP. An error diffusion algorithm is, then, applied to compensate for the differences in the gray levels.

• Journal of Aerospace System Engineering
• /
• v.9 no.4
• /
• pp.49-54
• /
• 2015

Accurate aerodynamic data is required for the flight simulation or control logic design of aircraft. The aerodynamic look-up table has been used widely to provide aerodynamic forces and moments for given flight conditions. In this paper, we replace the aerodynamic look-up table with real-time aerodynamic model which calculates aerodynamic forces and moments of quasi-steady flow directly for given flight conditions and control surface deflections. Flight simulations are conducted for the low-speed small UAV using real-time aerodynamic model, and responses of the UAV are predicted successfully for inputs of control surfaces.

• Journal of the Korean Institute of Telematics and Electronics B
• /
• v.29B no.9
• /
• pp.76-87
• /
• 1992

A novel self-organizing fuzzy plus PD control algorithm is proposed, where the proposed controller consists of a typical fuzzy reasoning part and self organizing part in which both on-line and off-line algorithms are employed to modify the Look-Up Table(LUT) for the fuzzy control rules and to decide how much fuzzy rules are to be modifid after evaluating the control performance, respectively. And the fuzzy controller is replaced by a PD controller in a prespecified region nearby the set point for good settling actions, where gain parameters are determined by fuzzy rules based on the magnitude of error velocity at the instant when the output penetrates into the prespecified region. To show the effectiveness of the proposed controller, extensive computer simulation results as well as experimental results are illustrated for an inverted pendulum system.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 1993.06a
• /
• pp.834-837
• /
• 1993

This paper describes the implementation of an autonomous fuzzy logic controller. The controller is endowed with basic control principles and learning constructs which enable it to autonomously modify its control policy based on system performance. The controller lies dormant when system response is satisfactory but if rapidly initiates adaptation in real time when adverse performance is observed. The autonomous fuzzy controller is implemented on an Intel MCS-51 series micro-controller board using an inexpensive 8-bit Intel 8031 processor. The 11.06 MHz micro-controller operates at a rate exceeding 200 "global" look-up table reinforcements per second. This is important when developing practical on-line adaptive controllers for fast systems. It is also significant because an initial controller look-up table could be incorrect or non-existent. The relatively high learning rate enables the controller to learn to control a system even while it is controlling it.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.25 no.2
• /
• pp.330-333
• /
• 2021

In a CNN for image classification, a SoftMax layer is usually placed at the end. The exponentinal and logarithmic operations in the SoftMax layer are not adequate to be implemented in an accelerator circuit. The operations are usually implemented with look-up tables, and the exponential operation can be implemented in an iterative method. This paper proposes a successive approximation method to calculate a logarithm to remove a very large look-up table. By substituing the large table with two very small tables, the circuit can be reduced much. The experimental results show that the 85% area reduction can be reached with a small error degradation.

• The Research Journal of the Costume Culture
• /
• v.6 no.4
• /
• pp.13-25
• /
• 1998

This study focuses on the visual effects of various neckline-haristyle combinations on the perception of face image and type. The study employed a model with oval face and examined 35 combinations made up of five necklines and seven hairstyles. Looking at various face images depending upon different necklines, in case of round, V, boat square, and high necklines, long wave hair and medium wave hair produced a feminine image of marked individuality; long straight hair that covers the forehead and medium straight hair gave an image of charm and purity as well as an image of neatness; and long straight hair short cut hair showed an intellectual image. Regarding the perceptual type of face depending upon the different necklines of round, V, square, and high, the long straight hair covering the forehead and medium wave hair had the effect of an optical illusion that made the face look short and round; and short cut hair made the face line look distinct and the face look oval and slender.

• Proceedings of the KSRS Conference
• /
• 2007.10a
• /
• pp.526-529
• /
• 2007

Due to its inherent feature of high-resolution satellite, there is strong need in some specific area to minimize the processing time required to get a standard image on hand from downlink signal acquisition. However, in general image processing system, it takes considerable time to get image data up to certain level from raw data acquisition because the huge amount of data is dealt sequentially as input data. This paper introduces the high-speed image processing system which generates the image data only for the area selected by user. To achieve the high speed performance, this system includes Quick Look Image display function with sampling, ROI selection function, Image Line Index function, and Distributed processing function. The developed RPS was applied to KOMPSAT-2 320Mbps downlink channel and its effectiveness was successfully demonstrated. This feature to provide the image product very quickly is expected to promote the application of high resolution satellite image.

• Communications of the Korean Institute of Information Scientists and Engineers
• /
• v.29 no.12
• /
• pp.75-82
• /
• 2011

• Journal of Korean Orthopaedic Sports Medicine
• /
• v.9 no.1
• /
• pp.28-34
• /
• 2010

Purpose: The aim of this study was to evaluate short-term clinical results and second-look arthroscopic findings after double-bundle anterior cruciate ligament (DB ACL) reconstruction. Materials and Methods: Forty-nine patients, who were followed up for at least 24 months after DB ACL reconstruction, were included. Clinical results, such as, Lysholm knee and Tegner activity scores, and manual laxity and instrumented anterior laxity test results were evaluated. In fifteen patients (15 knees), second-look arthroscopy with staple removal was performed. At second-look arthroscopy, the authors assessed about reconstructed ACL rupture, subjective graft tension and extent of synovial coverage. Results: Lysholm knee scores significantly improved from 67.4 preoperatively to 96.1 at last follow-up (p<0.01). Tegner activity scale improved from 2.0 to 6.1. The Lachman test, at last follow-up, showed normal laxity in 39 (of 49) patients, and the pivot-shift test showed normal laxity in 36 (of 49) patients. Mean side-to-side differences improved significantly from 10.8 mm to 3.3 mm (p<0.01). Second-look arthroscopic findings showed that all patients had a normal or a near normal anteromedial bundle. However, 8 patients (53.3%) were found to have partial or complete posterolateral bundle rupture. Conclusion: Even though double-bundle ACL reconstruction was clinically effective means of restoring knee rotational and anteroposterior stabilities, there were some ruptured posterolateral bundles observed in cases under arthroscopy after double-bundle ACL reconstruction.