• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.10
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• pp.909-919
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• 2014

License plate (LP) detection is the most imperative part of an automatic LP recognition (LPR) system. Typical LPR contains two steps, namely LP detection (LPD) and character recognition. In this paper, we propose an efficient Vehicle-to-LP detection framework which combines with an adaptive GMM (Gaussian Mixture Model) and a cascade of boosted classifiers to make a faster vehicle LP detector. To develop a background model by using a GMM is possible in the circumstance of a fixed camera and extracts the motions using background subtraction. Firstly, an adaptive GMM is used to find the region of interest (ROI) on which motion detectors are running to detect the vehicle area as blobs ROIs. Secondly, a cascade of boosted classifiers is executed on the blobs ROIs to detect a LP. The experimental results on our test video with the resolution of $720{\times}576$ show that the LPD rate of the proposed system is 99.14% and the average computational time is approximately 42ms.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.76.2-76
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• 2002

Because of the wheeled mobile robot is modeled by nonlinear system framework and controlled by nonlinear algorithms or fuzzy algorithms, the treatment of wheeled mobile robot is very complecate and conservative. In this paper, a new model of two wheeled mobile robot, which is a type of linear system and treated easily, is presented. And we will show that the control algorithms based on the linear system theory is well work to the wheeled mobile robot by simulation and experiment.

• Journal of Space Technology and Applications
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• v.3 no.2
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• pp.144-153
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• 2023

The existing military satellite communication system was based on geostationary satellites equipped with special communication payloads against enemy's jamming and signal reception. With the advent of new weapon systems such as unmanned systems, the need for low-orbit satellite-based communication system is increasing. This paper introduces various waveform technologies suitable for cube satellite-based communication system and the operational concept of a future military nanosatellite communication system.

• Journal of Information Processing Systems
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• v.12 no.4
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• pp.661-680
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• 2016

The vehicle license plate recognition (VLPR) system analyzes and monitors the speed of vehicles, theft of vehicles, the violation of traffic rules, illegal parking, etc., on the motorway. The VLPR consists of three major parts: license plate detection (LPD), license plate character segmentation (LPCS), and license plate character recognition (LPCR). This paper presents an efficient method for the LPCS and LPCR of Korean vehicle license plates (LPs). LP tilt adjustment is a very important process in LPCS. Radon transformation is used to correct the tilt adjustment of LP. The global threshold segmentation method is used for segmented LP characters from two different types of Korean LPs, which are a single row LP (SRLP) and double row LP (DRLP). The cross-correlation matching method is used for LPCR. Our experimental results show that the proposed methods for LPCS and LPCR can be easily implemented, and they achieved 99.35% and 99.85% segmentation and recognition accuracy rates, respectively for Korean LPs.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.3
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• pp.400-405
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• 1998

본 논문에서는 한국형 원자력 발전소의 기준모델인 영광 3,4호기 운전원 훈련용 시뮬레이터의 모델링 절차와 ABB-CE 원전의 독특한 계통인 CPC/COLSS (Core protection Calculator/Core Operating Limit Supervisory System) 계통에 대한 모델링을 전개허고 있다. CPC/COLSS는 원자로를 포함하는 냉각재계통(NSSS)과 핵연료의 건전성을 보장하기위한 계통으로서 감시및 보호 과정에서의 계산을 디지털화시킴으로서 정확성과 함께 원자로의 안정성을 향상시킨 특색있는 계통이다. 따라서 영광 3,4호기 시뮬레이터에서는 CPC/COLSS 계통에 대한 정확한 모델링을 하여 시험을 통해 성능및 기능에 대한 검증을 마침으로서 CPC/COLSS 시뮬레이션 모델 개발이 성공적으로 되었고 영광 3,4호기 운전 특성에 맞는 시뮬레이터를 개발하였다.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05a
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• pp.303-308
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• 1996

영광 3,4호기 노심보호연산기(CPC)와 노심감시계통(COLSS)의 운전성 시험은 실시간 (on-line)으로 측정된 노심보호연산기 및 노심감시계통의 결과들(DNBR, LPD, DNBR 출력제한치, LHR 출력제한치)을 노심보호 연산기 및 노심 감시계통 각각의 시뮬레이터 시스템(CEDIPS/CPC FORTRAN, COLSS FORTRAN)의 계산 결과와 비교하여 그 타당성을 검증하는 것이다. 그러나 기존의 노심보호연산기 및 노심감시계통의 운전성 시험자료 취득 방법은 관측(CPC)과 상세 보고서(COLSS)에 의한 것으로 정확한 자료 취득에 어려움이 있고 많은 시간이 소요되며 또한 자료 취득시 실수유발 가능성이 높다. 따라서 본 연구에서는 발전소 전산계통(Plant Computer System)으로부터 발전소 운전 상황을 순간적으로 기록한 자료(Snapshot)를 취하여 노심보호 연산기 및 노심감시계통 운전성 시험에 필요한 자료를 자동으로 얻는 방법을 고안하였다. 또한 발전소 Snapshot으로부터 필요한 자료를 자동으로 얻어내기 위하여 컴퓨터 프로그램(CODAP)도 개발하였다. 본 연구에서 고안된 방법은 영광 3호기 1주기 CPC/COLSS 운전성 시험에서 검증이 되어 영광4호기 1주기에 적용하였고, 이후의 후속기에도 적용할 예정이다.

• Nuclear Engineering and Technology
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• v.27 no.6
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• pp.877-887
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• 1995

YGN 3 is the first nuclear power plant to use the Core Protection Calculator (CPC) as the core protection system and the Core Operating Limit Supervisory System (COLSS) as the core monitor-ing system in Korea. The CPC is designed to provide on-line calculations of Departure from Nucleate Boiling Ratio (DNBR) and Local Power Density (LPD) and to initiate reactor trip if the core conditions exceed the DNBR or LPD design limit. The COLSS is designed to assist the operator in implementing the Limiting Conditions for Operation (LCOs) in Technical Specifications for DNBR/Linear Heat Rate (LHR) margin, azimuthal tilt, and axial shape index and to provide alarm when the LCOs are reached. During YGN 3 initial startup testing, extensive CPC/COLSS related tests ore peformed to ver-ify the CPC/COLSS performance and to obtain optimum CPC/COLSS calibration constants at var, -ious core conditions. Most of test results met their specific acceptance criteria. In the case of missing the acceptance criteria, the test results ore analyzed, evaluated, and justified. Through the analysis and evaluation of each of the CPC/COLSS related test results, it can be concluded that the CPC/COLSS are successfully Implemented as designed at YGN 3.

• Laser Solutions
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• v.18 no.3
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• pp.1-5
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• 2015

A 3D printer based on laser powder deposition (LPD), also known as DED (direct energy deposition), has been developed for fabricating metal parts. The printer uses a ytterbium fiber laser (1070nm, 1kW) and is equipped with an Ar purge chamber, a three-dimensional translation stage and a powder feeding system composed of a powder chamber and delivery nozzles. To demonstrate the performance of the printer, a tapered cylinder of 320mm in height has been fabricated successfully using Ti-6Al-4V powders. The process parameters including the laser output power, the scan speed, and the powder feeding rate have been optimized. A 3D printed test specimen shows mechanical properties (yield strength, ultimate tensile strength, and elongation) exceeding the criteria to employed in a variety of Ti alloy applications.

• Journal of the Korean Society of Systems Engineering
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• v.17 no.2
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• pp.49-60
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• 2021

The Core Protection Calculator System (CPCS) is vital for plant safety as it ensures the required Specified Acceptance Fuel Design Limit (SAFDL) are not exceeded. The CPCS generates trip signals when Departure from Nucleate Boiling Ratio (DNBR) and Local Power Density (LPD) exceeds their predetermined setpoints. These setpoints are established based on the operating margin from the analysis that produces the SAFDL values. The goal of this research is to create a simplified CPCS that optimizes operating margin for I-SMRs. Because the I-SMR is compact in design, instrumentation placement is a challenge, as it is with Ex-core detectors and RCP instrumentation. The proposed CPCS addresses the issue of power flux measurement with In-Core Instrumentation (ICI), while flow measurement is handled with differential pressure transmitters between Steam Generators (SG). Simplification of CPCS is based on a Look-Up-Table (LUT) for determining the CEA groups' position. However, simplification brings approximations that result in a loss of operational margin, which necessitates compensation. Appropriate compensation is performed based on the result of analysis. FPGAs (Field Programmable Gate Arrays) are presented as a way to compensate for the inadequacies of current systems by providing faster execution speeds and a lower Common Cause Failure rate (CCF).

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.12
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• pp.1114-1125
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• 2013

License Plate Detection (LPD) is a key component in automatic license plate recognition system. Despite the success of License Plate Recognition (LPR) methods in the past decades, the problem is quite a challenge due to the diversity of plate formats and multiform outdoor illumination conditions during image acquisition. This paper aims at automatical detection of car license plates via image processing techniques. In this paper, we proposed a real-time and robust method for license plate detection using Heuristic Energy Map(HEM). In the vehicle image, the region of license plate contains many components or edges. We obtain the edge energy values of an image by using the box filter and search for the license plate region with high energy values. Using this energy value information or Heuristic Energy Map(HEM), we can easily detect the license plate region from vehicle image with a very high possibilities. The proposed method consists two main steps: Region of Interest (ROI) Detection and License Plate Detection. This method has better performance in speed and accuracy than the most of existing methods used for license plate detection. The proposed method can detect a license plate within 130 milliseconds and its detection rate is 99.2% on a 3.10-GHz Intel Core i3-2100(with 4.00 GB of RAM) personal computer.