• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1993년도 추계학술대회 논문집
• /
• pp.550-555
• /
• 1993

The aim of this paper is to present the development of visual seam tracking system equipped with visual range finder. The visual range finder, which consists of a CCD camera and a diode laser system with line generating optics, developed to recognize the types of weld joints and detect the location of weld joints. In practical applications, however, images of the weld joints are often degraded due to spatters, are flares, surface specularity, and welding smoke. To overcome the problem, this paper proposes a syntactic approach which is a class of artificial intelligence techniques. In the approach, the type of weld joint is inferred based upon the production rules which are linguiques grammars consisting of a set of line and junction primitives of laser strip image projected on weld joint. The production rules eliminate several noisy primitives to create new primitives through the merging process of primitives. After the recognition of weld joint, arc welding is started and the location of weld joints is repeatedly detected using a spring model-based template matching in which the template model is a by-product of the recognition process of weld joint. To show the effectiveness of the proposed approach a series of experiments-identification and robotic tracking-are conducted for four different types of weld joints.

• 한국통신학회논문지
• /
• 제16권2호
• /
• pp.180-195
• /
• 1991

본 논문은 한글 문자 패턴을 인식하기 위하여 쉐이프 패턴을 대상으로 한글의 구조적 정보를 이용한 새로운인식 방법에 대해서 연구하였다. 먼저, 입력된 데이타에 대하여 문자의 위치를 알기 위하여 문자 영역의 블럭화를 행하였고, 둘째로 한글의 무게 중심을 이용한 종모음의 유무를 결정하고, 횡모음과 짧은 기둥의 위치와 길이 조사 및 종정의 존재 여부를 조사하여 한글이 가지는 6가지의 기본 구조로 형식 분류를 하였으며, 마지막으로 분류된 형식에 따라 각각의 자소에 대해 유크리드 기리(Uclid distance)에 의한 탬플레이트 매칭(template matching)을 실행하여 인식을 행하였다. 본 연구는 실험을 통하여 총 2350자의 문자에 대하여 98.3%의 형식 분류율과 95.2%의 한글 인식율을 얻었다.

• 한국멀티미디어학회논문지
• /
• 제19권11호
• /
• pp.1837-1851
• /
• 2016

Newspaper reader mobile applications using text-to-speech (TTS) function enable blind people to read newspaper contents. But, tables cannot be easily read by the reader program because most of the tables are stored as images in the contents. Even though we try to use OCR (Optical character reader) programs to recognize letters from the table images, it cannot be simply applied to the table reading function because the table structure is unknown to the readers. Therefore, identification of exact location of each table cell that contains the text of the table is required beforehand. In this paper, we propose an efficient image processing algorithm to recognize all the cells in tables by identifying columns and rows in table images. From the cell location data provided by the table column and row identification algorithm, we can generate table structure information and table reading scenarios. Our experimental results with table images found commonly in newspapers show that our cell identification approach has 100% accuracy for simple black and white table images and about 99.7% accuracy for colored and complicated tables.

• Journal of Computing Science and Engineering
• /
• 제5권3호
• /
• pp.161-166
• /
• 2011

We present a fast algorithm for Korean text extraction and segmentation from subway signboards using smart phone sensors in order to minimize computational time and memory usage. The algorithm can be used as preprocessing steps for optical character recognition (OCR): binarization, text location, and segmentation. An image of a signboard captured by smart phone camera while holding smart phone by an arbitrary angle is rotated by the detected angle, as if the image was taken by holding a smart phone horizontally. Binarization is only performed once on the subset of connected components instead of the whole image area, resulting in a large reduction in computational time. Text location is guided by user's marker-line placed over the region of interest in binarized image via smart phone touch screen. Then, text segmentation utilizes the data of connected components received in the binarization step, and cuts the string into individual images for designated characters. The resulting data could be used as OCR input, hence solving the most difficult part of OCR on text area included in natural scene images. The experimental results showed that the binarization algorithm of our method is 3.5 and 3.7 times faster than Niblack and Sauvola adaptive-thresholding algorithms, respectively. In addition, our method achieved better quality than other methods.

• 한국통신학회논문지
• /
• 제31권3C
• /
• pp.293-301
• /
• 2006

본 논문에서는 Ubi-Home에서의 지능적 멀티미디어 스트리밍을 지원하는 콘텐츠 보호 및 관리 시스템(UHSMS-DRM: Ubi-Home Smart Multimedia Streaming-Digital Right Management)을 설계 및 구현하였다. 제안 시스템은 Ubi-Home에서 디지털 콘텐츠의 저작권 보호 및 관리를 위한 유연한 유통 플랫폼을 제공하며, PC, STB, PDA, Portable device 등 다양한 디바이스의 인증을 통해 정당한 사용자에게 Multimedia Steaming Service를 제공한다. 그리고, 도메인 인증개념을 적용하여 Ubi-Home의 모든 디바이스에 대한 라이센스 관리의 효율성을 높인다. 또한, Ubi-Home에서 intelligent Service를 위해 사용자의 위치를 인지하기 위한 알고리즘을 제안 및 적용한다.

• 대한전기학회논문지
• /
• 제40권8호
• /
• pp.731-740
• /
• 1991

This paper presents a knowledge based system to solve reactive power/voltage control problem in a power system. The methods to reduce inference time are proposed in inferring the solution of problem in the knowledge base which consists of heuristic rules and inowledge of experts. A set of indices drawn from the heuristic knowledge on the power system is utilized to make up for the defect of existing knowledge based systems which determine both the location and the amount of reactive power compensation devices. The concept of set of indices developed in this paper makes it possible to infer the amount of reactive power source only since the bus order list representing priority for the location of reactive power compensator to be switched on can be determined in advance. From the fact that there exists a relationship between the system voltage pattern and the reactive power pattern in operation, the pattern recognition technique is introduced to reduce the inference time in solving the severe voltage problem. To demonstrate the usefulness of the proposed knowledge based system, the IEEE 30 bus system is chosen as a sample system. The results of case study are also presented.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2005년도 추계학술대회 논문집 전력기술부문
• /
• pp.283-285
• /
• 2005

This paper presents a new two-terminal numerical algorithm for fault location estimation and for faults recognition using the synchronized phasor in time-domain. The proposed algorithm is also based on the synchronized voltage and current phasor measured from the PMUs(Phasor Measurement Units) installed at both ends of the transmission lines. Also the arc voltage wave shape is modeled numerically on the basis of a great number of arc voltage records obtained by transient recorder. From the calculated arc voltage amplitude it can make a decision whether the fault is permanent or transient. In this paper the algorithm is given and estimated using DFT(Discrete Fourier Transform) and the LES(Least Error Squares Method). The algorithm uses a very short data window and enables fast fault detection and classification for real-time transmission line protection. To test the validity of the proposed algorithm, the Electro-Magnetic Transient Program(EMTP/ATP) and MATLAB is used.

• 대한기계학회논문집A
• /
• 제39권6호
• /
• pp.603-610
• /
• 2015

본 논문에서는 기울기 센서와 고도계 센서로 구성된 다중모드 센서를 통하여 일정 공간내의 거주자의 자세 및 행동 패턴을 수집, 분석하여 거주자의 위치를 추론함으로써, 현재 거주자가 위치한 공간을 인지하는 시스템을 제안한다. 여기에서 제안된 센서 시스템의 하드웨어 구성과 소프트웨어 알고리즘에 대하여 설명하고, 다중모드 센서를 통하여 획득한 데이터로부터 거주자의 자세 및 행동을 분석한 후에 거주자가 존재하는 공간을 추론하는 프로세스에 대하여 설명한다. 마지막으로 거주자의 자세 및 행동 분석과 공간인지 기능을 검증하기 위하여 실제 환경 실험을 통하여 본 논문에서 제안한 시스템의 효용성과 타당성을 검토한다.

• Journal of Multimedia Information System
• /
• 제7권1호
• /
• pp.11-16
• /
• 2020

Deep Learning has become the most important technology in the field of artificial intelligence machine learning, with its high performance overwhelming existing methods in various applications. In this paper, an interactive window service based on object recognition technology is proposed. The main goal is to implement an object recognition technology using this deep learning technology to remove the existing eye tracking technology, which requires users to wear eye tracking devices themselves, and to implement an eye tracking technology that uses only usual cameras to track users' eye. We design an interactive system based on efficient eye detection and pupil tracking method that can verify the user's eye movement. To estimate the view-direction of user's eye, we initialize to make the reference (origin) coordinate. Then the view direction is estimated from the extracted eye pupils from the origin coordinate. Also, we propose a blink detection technique based on the eye apply ratio (EAR). With the extracted view direction and eye action, we provide some augmented information of interest without the existing complex and expensive eye-tracking systems with various service topics and situations. For verification, the user guiding service is implemented as a proto-type model with the school map to inform the location information of the desired location or building.

• 한국정보통신학회논문지
• /
• 제15권8호
• /
• pp.1813-1819
• /
• 2011

본 연구에서 제안하는 위치인식시스템은 전파의 위상 및 크기를 이용하여 거리를 구하고 여기서 구한 거리 정보를 보다 정확하게 측정하기 위해서 비젼에 의한 영상 히스토그램 기법을 이용하여 보완하는 기술이다. 제안하는 기술은 거리측정용 무선송수신기로부터 송수신된 900Mhz대 RF 신호로부터 중간주파수인 450Khz의 아날로그 데이터를 디지털신호처리를 통하여 얻어내며, 여기서 얻어진 거리 정보에다 비젼에 의해 얻어진 거리를 상호 보완하여 보다 정확한 거리 정보를 획득한다. 측정된 거리의 평가를 위해서 실제거리와 측정된 거리를 비교 분석하고, 또한 평균처리 및 진폭특성을 통한 측정오차 개선 방법과 기존의 RF 신호만 이용하는 경우와 비교 검토한다.