• Journal of Broadcast Engineering
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• v.13 no.5
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• pp.565-573
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• 2008

This paper proposes noise reduction methods to improve the channel estimation performance in Equalization On-Channel Repeater (E-OCR) for Terrestrial-Digital Multimedia Broadcasting (T-DMB) system. In the E-OCR for T-DMB system, the channel estimation is performed by the pilot signal extraction and the channel coefficient estimation. Since the performance of the channel estimation highly depends on the estimated channel coefficients whose accuracy is associated with the received signal-to-noise ratio (SNR), it is important to reduce noise existing at the estimated channel coefficients. To reduce such noise components, various noise reduction methods of the estimated channel coefficients based on the M -point weighted moving average are proposed. Computer simulations show that the proposed methods improve the estimation performance by more than 2 to 3 dB in terms of the symbol error rate after equalization.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2008.11a
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• pp.23-26
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• 2008

본 논문에서는 T-DMB 시스템의 단일 주파수 망 구성을 위해 궤환신호 제거기를 가지는 등화형 OCR (Equalization On-Channel Repeater, E-OCR)을 제안한다. 제안된 OCR은 송/수신 안테나의 충분치 못한 분리도로 인해 야기된 궤환신호를 궤환간섭 제거기를 통해 제거하여 송신출력을 높일 뿐만 아니라, 송신기와 중계기 사이의 다중경로 신호를 등화기를 통해 제거하여 우수한 출력신호 품질을 보장한다. 또한, 본 논문에서는 전산실험을 통해 제안된 OCR의 성능을 살펴보고 실험실 테스트를 통해 실제 구현된 OCR의 성능을 검증한다.

• The KIPS Transactions:PartD
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• v.17D no.1
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• pp.59-66
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• 2010

Traditional OCR engines are designed to the scanned documents in calibrated environment. Three dimensional perspective distortion and smooth distortion in images are critical problems caused by un-calibrated devices, e.g. image from smart phones. To meet the growing demand of character recognition of texts embedded in the photos acquired from the non-calibrated hand-held devices, we address the problem in three categorical aspects: rotational invariant method of text region extraction, scale invariant method of text line segmentation, and three dimensional perspective mapping. With the integration of the methods, we developed an OCR for camera-captured images.

• KIEE International Transactions on Power Engineering
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• v.5A no.4
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• pp.357-365
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• 2005

This research investigates the influences of distributed generations (DG), which are interconnected to the bus by the dedicated lines, on the overcurrent relays (OCR) of the neighboring distribution feeders and also proposes a novel method to reduce the negative effects on the feeder protection. Due to the grid connected DG, the entire short-circuit capacity of the distribution networks increases, which may raise the current of the distribution feeder during normal operations as well as fault conditions. In particular, during the switching period for loop operation, the current level of the distribution feeder can be larger than the pickup value for the fault of the feeder's OCR, thereby causing the OCR to perform a mal-operation. This paper proposes the adaptive setting algorithm for the OCR of the distribution feeders having the neighboring dedicated feeders for the DG to prevent the mal-operations of the OCR under normal conditions. The proposed method changes the pickup value of the OCR by adapting the power output of the DG monitored at the relaying point in the distribution network. We tested the proposed method with the actual distribution network model of the Hoenggye substation at the Korea Electric Power Co., which is composed of five feeders supplying the power to network loads and two dedicated feeders for the wind turbine generators. The simulation results demonstrate that the proposed adaptive protection method could enhance the conventional OCR of the distribution feeders with the neighboring dedicated lines for the DG.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11a
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• pp.85-88
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• 2002

e-book은 책을 종이가 아닌 전자형태로 출판하는 것이다. 이러한 e-book 은 기존의 책들과는 달리 다양한 서비스를 제공할 수 있으며 가격이나 책의 재고관리와 같은 경제적인 부분에서도 소비자나 출판사입장에서 상당한 이득을 기대 할 수 있다. 일반적으로 e-book 은 OCR(문자 인식기)을 사용하여 생성되는데 OCR 의 문자인식률은 일반적으로 95%정도이며 인식된 텍스트 문서에 대한 교정이 필요하다. 그러나 기존의 워드 프로세서들은 간단한 수준의 교정기능만이 제공되고 있다. 본 논문에서는 교정을 보다 효율적으로 수행할 수 있는 교정 편집기를 설계하고, 구현한다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.38-38
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• 2009

Characteristics of the photonic bandgaps (PBGs) in two-dimensional photonic crystals (2D PCs) with a hexagonal lattice have theoretically studied using a finite difference time domain (FDTD) simulation. In this research, we propose a concept of optical coverage ratio (OCR) as a new structural parameter to determine the PBGs for E-polarized light. The OCR is an optically compensated filling factor. It is possible to normalize the PBGs of 2D PCs by introducing the OCR.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.1
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• pp.61-66
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• 2009

Characteristics of the photonic bandgaps (PEGs) in two-dimensional photonic crystals (2D PCs) with a square lattice have theoretically studied using a finite difference time domain (FDTD) simulation. In this paper, we propose a concept of optical coverage ratio (OCR) as a new structural parameter to determine the PEGs for E-polarized light. The OCR is an optically compensated filling factor. It is possible to normalize the PEGs of 2D PCs by introducing the OCR.

• Journal of the Korean Society for information Management
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• v.9 no.1
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• pp.131-164
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• 1992

In this study. a technical report management system using optical technology is described in detail. This management system is designed for both bibliographic (character) and full-text (image) information. Several optical filing systems already on the Korean market are scrutinized and compared with standard functions in order to build a more efficient management system for technical reports which can be easily integrated into existing KRISS library automation system. For that purpose, up-to-date technologies (i.e., digital image PI-ocessing (DIP), MARC standards, and optical character recognition (OCR), etc.) are applied to this system.

• Journal of the Semiconductor & Display Technology
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• v.22 no.4
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• pp.154-160
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• 2023

Recently, with the activation of eBook services, books are being published simultaneously as physical books and digitized eBooks. Paper books are more expensive than e-books due to printing and distribution costs, so demand for relatively inexpensive e-books is increasing. There are cases where previously published physical books cannot be digitized due to the circumstances of the publisher or author, so there is a movement among individual users to digitize books that have been published for a long time. However, existing research has only studied the advancement of the pre-processing process that can improve text recognition before applying OCR technology, and there are limitations to digitization depending on the condition of the book. Therefore, support for book digitization services depending on the condition of the physical book is needed. need. In this paper, we propose a method to support digitalization services according to the status of physical books held by book owners. Create images by scanning books and extract text information from the images through OCR. We propose a method to recover text that cannot be extracted depending on the state of the book using BERT, a natural language processing deep learning model. As a result, it was confirmed that the recovery method using BERT is superior when compared to RNN, which is widely used in recommendation technology.

• Journal of the Korea Society of Computer and Information
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• v.29 no.5
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• pp.31-38
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• 2024

In this paper, we propose an ASAP(AI-driven Service for Advertisement Production) application that provides a generative AI-based automatic advertising image production service. This application utilizes GPT-3.5 Turbo Instruct to generate suitable background mood and promotional copy based on user-entered keywords. It utilizes OpenAI's DALL·E 3 model and Stability AI's SDXL model to generate background images and text images based on these inputs. Furthermore, OCR technology is employed to improve the accuracy of text images, and all generated outputs are synthesized to create the final advertisement. Additionally, using the PILLOW and OpenCV libraries, text boxes are implemented to insert details such as phone numbers and business hours at the edges of promotional materials. This application offers small business owners who face difficulties in advertising production a simple and cost-effective solution.