• 제어로봇시스템학회논문지
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• 제12권6호
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• pp.568-572
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• 2006

This paper presents the device of recognizing image of the studded paving blocks, transmitting, the information by vibration to a visually handicapped person. Usually the blind uses the walking stick to recognize the studded paving block. This research uses a PCA (Principal Component Analysis) based image processing approach for recognizing the paving blocks. We classify the studded paving blocks into 5 classes, that is, vertical line block, right-declined line block, left-declined line block, dotted block and flat block. The 8 images for each of 5 classes are captured for each block by 112*120 pixels, then the eigenvectors are obtained in magnitude order of eigenvectors by using principal component analysis. The principal components for images can be calculated using projection of transformation matrix composed of eigenvectors. The classification has been executed using Euclidean's distance, so the block having minimum distance with a image is chosen as matched one. The result of classification is transmitted to the blind by electric vibration signals with different magnitudes and frequencies.

• 정보보호학회논문지
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• 제18권2호
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• pp.85-96
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• 2008

실행코드의 변조와 역분석(reverse engineering)을 방지하기 위한 대표적인 방법은 실행코드를 암호화하는 것이다. 본 논문에서는 키 체인(key chaining) 방식의 블록암호화 기법을 이용하여 응용프로그램을 암호화하는 방법을 제안한다. 키체인 방식의 블록암호화 기법은 키가 블록의 내부에 은닉되어 있고 각 블록의 키가 서로 다르다는 장점을 갖지만, 제어이동을 필요로 하는 프로그램에 적용하기에는 적합하지 않다고 알려져 있다. 본 논문에서는 실행코드에서의 제어이동 명령어에 대해서도 키체인 방식을 효과적으로 적용할 수 있도록 블록을 변형시키거나 중복시키는 방법을 제시하고, MIPS 명령어집합을 이용하여 가능성을 분석한다.

• Advances in pediatric surgery
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• 제20권1호
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• pp.7-11
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• 2014

The present study compared the postoperative analgesic effects of ilioinguinal and iliohypogastric nerve block with infiltration of local anesthetics (bupivacaine) into the wound in children after inguinal hernia repair. Ninety children below 7 years old who were scheduled elective inguinal hernia repair were randomly allocated into one of three groups. The patients in nerve block (NB) group, ilioinguinal and iliohypogastric nerve block was done with 0.5 mL/kg of 0.25% bupivacaine. The patients in infiltration of local anesthetics (LI) group, 0.5 mL/kg of 0.25% bupivacaine was infiltrated into the wound after surgery. The patients in control group were allocated as a Control group. Postoperative pain was assessed at 1, 3, 5, and 24 hours after operation with FLACC scale and additional analgesic consumption were counted. The three groups were not significantly different in age, sex, body weight, and duration of operation. Pain scores at 1 hour and 3 hours after operation were significantly higher in Control group than in NB group and LI group (p<0.01), whereas there were no difference between NB group and LI group. The rescue analgesics administration was significantly higher in Control group (n=11) than in NB group (n=6) and LI group (n=7) (p<0.05). There were 2 cases of transient femoral nerve palsy in NB group. Both of ilioinguinal and iliohypogastric nerve block and infiltration of local anesthetics into the wound provided effective postoperative analgesia in early postoperative period following inguinal hernia repair in children. But no difference between the two methods. Technically, infiltration of local anesthetics into the wound was easier and safer than ilioinguinal and iliohypogastric nerve block.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.109-112
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• 1997

In this note, we investigate a noniterative design method of an observer-based robust H$\_$2/ controller in the presence of structured real parameter uncertainty by applying Riccati approach based on the guaranteed cost function. Motivated by the numerical difficulty of the problem, we try to develop a simple design method named as block-diagonal approach, which can be solved by the LMIs method. By assuming the block-diagonal structure of Riccati solution, the original problem can be derived into two sequentially decoupled optimization problems as LQG control problem. The proposed method seems to be numerically efficient in obtaining a feasible compensator.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.2169-2170
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• 2011

This paper presents about the analysis on cost factor reduction using the life cycle cost model for motor block in the KTX-1. Until now, most life cycle cost of the system as a whole that has been studied. but in case of railway industry part, LCC studies are needed on the subsystem like a propulsion control system because subsystems are developed continuously localization. Therefore, In this paper presents cost breakdown structure for life cycle cost (LCC) estimation for localization development of propulsion control system (Motor Block) in high speed railway vehicle (KTX-1). Also to analysis LCC on motor block, it was analyzed physical breakdown structure (PBS) and preventive cost on propulsion control system in view of maintenance cost. Based on this, we describe life cycle cost on motor block of KTX-1.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.34.1-34
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• 2001

We deal with robust control problem for singularly perturbed linear systems with norm-bounded structured uncertainty under state constraints. We assume that the norm-bounded uncertainty is composed of repeated scalar-block and full-block forms. In the structured uncertainty, repeated scalar block forms account for uncertain physical parameter value and full-block forms may be some unknown nonlinear dynamics. In order deal with uncertainty and state constraints, we use LMI(Linear Matrix Inequality). The original problem is decomposed into two well behaved reduced order problems. Shinc two LMI problems are completely independent, each solution can be computed simultaneously and work in parallel.

• 한국철도학회논문집
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• 제14권6호
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• pp.575-583
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• 2011

철도 지선 구간의 유지보수 비용을 최소화하기 위해 ICT 기반 차상제어시스템을 개발 중이다. 이 시스템은 기존의 열차제어방식과 달리 선로 주변 신호기와 고정폐색장치를 없애고 이동폐색방식을 적용하며 차상에서 선로전환기와 건널목을 제어하는 방식이다. 본 논문의 목적은 ICT 기반 차상제어시스템 개발 이전에 고려해야 할 주요 운영 이슈 사항을 분석하며 주요 대상은 열차운행준비, 운전 편의성, 관제역할, 폐색방식, 그리고 운영비용을 고려하였다. 열차 출발 전에 기관사가 DMI를 통해 입력하여야 할 입력데이터를 정의하였고 관련 업무 프로세스를 UML 도구를 활용하여 설계하였다. 기관사의 운전 편의성 측면에서는 역 진입 시의 제동시점 지원 필요성과 기관사의 원활한 운전 훈련을 위한 운전시뮬레이터가 필요하다. 기관사가 선로전환기와 건널목을 직접 제어하는 업무절차를 UML 도구로 설계하였다. 기존 운영 방식과의 차이를 확인하기 위해 고정폐색방식과 이동폐색방식 간에 비교 분석하였으며, 비용 측면에서는 기존방식과 ICT 방식의 신호설비에 따른 유지보수 비용 이점을 제시하였다.

• 전자공학회논문지C
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• 제35C권11호
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• pp.21-30
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• 1998

본 논문에서는 FPGA를 이용하여 산업용 구동장치로 널리 사용되고 있는 유도 전동기의 디지털 전류 제어시스템을 구현하였다. 이를 위해 VHDL을 이용하여 FPGA를 설계하였으며 이 FPGA는 PWM 발생부, PWM 보호부, 회전속도 검출부, 프로그램 폭주 방지부, 인터럽트 발생부, 디코더 로직부, 신호 지연 발생부 및 디지털 입·출력부로 각각 구성되어있다. 본 FPGA의 설계시 고속처리의 문제점을 해결하기 위해 클럭전용핀을 활용하였으며 또한 40 MHz에서도 동작할 수 있는 삼각파를 만들기 위해 업다운 카운터와 래치부를 병렬 처리함으로써 고속화하였다. 특히 삼각파와 각종 레지스터를 비교 연산할 때 많은 팬아웃 문제에 따른 게이트 지연(gate delay) 요소를 줄이기 위해 병렬 카운터를 두어 고속화를 실현하였다. 아울러 삼각파의 진폭과 주파수 및 PWM 파형의 데드 타임 등을 소프트웨어적으로 가변 하도록 하였다. 이와 같은 기능들을 FPGA로 구현하기 위하여 퀵로직(Quick Logic)사의 pASIC 2 SpDE와 Synplify-Lite 합성툴을 이용하여 로직을 합성하였다. 또한 Verilog HDL 환경에서 최악의 상황들(worst cases)에 대한 최종 시뮬레이션이 성공적으로 수행되었다. 아울러 구현된 FPGA를 84핀 PLCC 형태의 FPGA로 프로그래밍 한 후 3상 유도전동기의 디지털 전류 제어 시스템에 적용하였다. 이를 위해 DSP(TMS320C31-40 MHz)와 FPGA, A/D 변환기 및 전류 변환기(Hall CT) 등을 이용하여 3상 유도 전동기의 디지털 전류 제어 시스템을 구성하였으며, 디지털 전류 제어의 효용성을 실험을 통해 확인하였다.

• Transactions on Control, Automation and Systems Engineering
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• 제4권3호
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• pp.205-211
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• 2002

Unknown inputs observer(UIO) which is achieved by the coordinate transformation method has the differential of system outputs in the observer and the equation for unknown inputs estimation. Generally, the differential of system outputs in the observer can be eliminated by defining a new variable. But it brings about the partition of the observer into two subsystems and need of an additional differential of system outputs still remained to estimate the unknown inputs. Therefore, the block pulse function expansions and its differential operation which is a newly derived in this paper are presented to alleviate such problems from an algebraic form.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2008년도 춘계학술대회 논문집
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• pp.249-251
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• 2008

In Factory Automation(FA) used by Programmable Logic Controller(PLC), Ladder Diagram(LD) is the most widely utilized and plays an important role in industrial control system. But recently, the study about Sequential Function Chart(SFC) is performed actively. When we program by SFC, generally, we design one routine from start to end. This method is difficult to design block control system, and we often make mistakes. In this paper, we propose the method that we design block control system and we analysis the difference of the method used this paper from conventional method.