• Title/Summary/Keyword: QR method

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A SOUND-QR Authentication Method for an Electronic Attendance System (전자출결시스템을 위한 SOUND-QR 인증 방안)

  • Kang, Jung-Hun;Sim, Hyeon-Seok;Seo, Seung-Hyun
    • Proceedings of the Korea Information Processing Society Conference
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    • 2022.05a
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    • pp.326-327
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    • 2022
  • 현행 전자출결 시스템은 강의실이 아닌 곳에서 지정된 숫자만 제공되면, 정당하지 않은 방법으로도 출석을 진행할 수 있다. 이런 맹점을 개선하기 위해 본 논문에서는 인증용 데이터를 텍스트가 아닌 음성 데이터를 이용한다. 본 논문에서 제안하는 SOUND-QR 인증 시스템은 음원을 전달할 때 특정 데이터가 포함된 음원을 잡음과 왜곡 환경에 강한 오디오로 변환하고 이러한 음원을 각 기기에서 입출력시 발생하는 특성 차이를 인증에 활용함으로써 현장에 있는 기기에서만 출결이 인정되도록 한다.

Vibration Analysis of a Bogie Using Linearized Dynamic Equations of a Multibody System (다물체계의 선형 동역학식을 이용한 대차의 진동 해석)

  • Kang, Juseok
    • Journal of the Korean Society for Railway
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    • v.17 no.5
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    • pp.321-327
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    • 2014
  • In this paper, linear dynamic equations are derived from nonlinear dynamic equations of constrained multibody systems using the QR decomposition method. The derived linear equations are applied to a railway vehicle bogie. The vibration characteristics of the railway vehicle are investigated by calculating the natural mode and transfer function of the bogie frame in relation to rail-roughness input. The main modes of the bogie were found below 35Hz, and the local modes above 198Hz. The magnitude of the vertical transfer function varied with the forward velocity due to vertical and pitch modes, which were influenced by the forward velocity. The magnitude of the lateral transfer function was negligibly small, and the mode in the longitudinal direction was excited for longitudinal transfer function regardless of the forward velocity.

Efficient m-step Generalization of Iterative Methods

  • Kim, Sun-Kyung
    • Journal of Korea Society of Industrial Information Systems
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    • v.11 no.5
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    • pp.163-169
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    • 2006
  • In order to use parallel computers in specific applications, algorithms need to be developed and mapped onto parallel computer architectures. Main memory access for shared memory system or global communication in message passing system deteriorate the computation speed. In this paper, it is found that the m-step generalization of the block Lanczos method enhances parallel properties by forming in simultaneous search direction vector blocks. QR factorization, which lowers the speed on parallel computers, is not necessary in the m-step block Lanczos method. The m-step method has the minimized synchronization points, which resulted in the minimized global communications and main memory access compared to the standard methods.

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A Study on Colored LED Tag Recognition Method based on 8MP CMOS Sensor (8MP CMOS센서기반 Colored LED Tag 인식 기법에 대한 연구)

  • Lee, Min-Woo;Jeong, Sun-Ho;Yang, Seung-Youn;Shin, Jae-Kwon;Kim, Jin-Tae;Lee, Jung-Hoon;Cha, Jae-Sang
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.1435-1435
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    • 2015
  • 광고 및 홍보의 마케팅 수단의 일환으로써 점포별로 QR코드를 사용하는 사례가 급격히 늘고 있다. 정보도트의 일종인 QR코드의 경우는 스마트폰과 더불어 홍보수단의 일환으로 활용되는 사례가 증가하고 있는 반면 QR코드는 정보를 표현할 수 있는 디자인의 범위가 좁고, 전송할 수 있는 Data의 용량이 적으며, 어두운 환경에서의 인식률이 저하되는 단점이 있다. 이에 기존의 QR코드 보다 다양한 디자인이 가능하고 대용량의 Data 전송이 가능한 컬러코드가 대두되고 있다. 컬러코드란 4가지 색상(빨강, 파랑, 초록, 검정)을 이용한 매트릭스 형태의 코드로 각종 디지털 정보를 저장하는 새로운 개념의 데이터 표현 기술이며, 이는 각 컬러에 디지털 정보를 매핑(mapping)하여 콘텐츠나 URL 등의 실제 정보들을 제공하는 역할을 하도록 설계되어 있다. 8MP CMOS센서기반 Colored LED Patch 인식 기법은 VLC에 포함되는 하나의 기술로서 차세대 조명 및 정보 디스플레이 장치로 각광을 받고 있는 반도체 조명 기술인 광원 정보 인식 기법이다. 따라서, 본 논문에서는 8MP CMOS센서 기반 컬러코드 LED Patch 인식 기법에 대해 제안하였다. 8MP CMOS 센서를 이용한 Colored LED Patch 인식 기법 중 하나로서 위치 정보 서비스 등 다양한 정보 획득이 가능하도록 연구하였으며, 동영상, 웹사이트 링크 등 여러 형식에 적용이 가능하도록 하였다. 본 연구에서 사용되는 8MP CMOS센서를 기반 Colored LED Patch 인식 기법을 통해 컬러코드는 코드 플랫폼으로 연결되어 콘텐츠의 위치를 파악하고 이용자에게 콘텐츠 및 정보가 전송된다. 이는 QR코드보다 높은 인식률로 빠르고 편리하게 정보를 제공할 수 있었다. 본 논문에서는 상기 제안 기술을 통하여 LED Patch의 높은 주목성과 가시성을 확보하여 보다 효과적인 광고 및 홍보의 시인성을 확보할 수 있다. 향후 본 제안기술을 통하여 사회 안전망을 위한 위치 및 정보 서비스 제공이 가능하며, 효과적인 광고 효과를 도출할 수 있을 것으로 사료된다.

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A Study of Connection of Facility DB for People with Disability to Smartphone for Location and Voice Recognition and QR Code Recognition and to Navigation (위치 음성인식 QR코드가 인식된 스마트폰과 네비게이션에 대한 장애인 편의시설 DB 연결)

  • Yang, Sung-Yong;Park, Dea-Woo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.177-180
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    • 2013
  • The number of people with a disability registered in the Korea's Ministry of Health and Welfare is more than 2.5 million in 2010, and approximately 2.51 million as of late 2012. In consideration of potential disabilities led by aging which is in fast progress in Korea, the number of people with a disability will further increase. It is necessary to study the method of enabling people with a disability to easily access facilities and of using facilities for people with a disability, in order to comply with the Disability Discrimination Act (DDA) which is enforced in Korea. In this study, a smartphone recently used more and more is used to develop a smartphone which can recognize locations, voice and the QR code for enabling people with a disability to recognize them. The developed smartphone for people with a disability is connected to a database established as a facility for people with a disability, and to the navigation system in the wheelchair accessible call taxis, to enable the disability database to be used. This study will contribute to observing the Disability Discrimination Act of Korea, and improving the national welfare system by enhancing the disability care services.

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A 2-Dimensional Barcode Detection Algorithm based on Block Contrast and Projection (블록 명암대비와 프로젝션에 기반한 2차원 바코드 검출 알고리즘)

  • Choi, Young-Kyu
    • The KIPS Transactions:PartB
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    • v.15B no.4
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    • pp.259-268
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    • 2008
  • In an effort to increase the data capacity of one-dimensional symbology, 2D barcodes have been proposed a decade ago. In this paper, we present an effective 2D barcode detection algorithm from gray-level images, especially for the handheld 2D barcode recognition system. To locate the symbol inside the image, a criteria based on the block contrast is adopted, and a gray-scale projection with sub-pixel operation is utilized to segment the symbol precisely from the region of interest(ROI). Finally, the segmented ROI is normalized using the inverse perspective transformation for the following decoding processes. We also introduce the post-processing steps for decoding the QR-code. The proposed method ensures high performances under various lighting/printing conditions and strong perspective deformations. Experiments shows that our method is very robust and efficient in detecting the code area for the various types of 2D barcodes in real time.

Study on time-varying herd behavior in individual stocks (개별 주가에 반영된 시변 무리행동 연구)

  • Park, Beum-Jo
    • Journal of the Korean Data and Information Science Society
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    • v.22 no.3
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    • pp.423-436
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    • 2011
  • Many of the theoretical studies have considered herd behavior as a source of the volatility in financial markets, but there have been few empirical studies on the dynamic herding due to the technical difficulty of detecting herd behavior with time-series data. In this context, this paper proposes a new method for measuring time-varying herd behavior based on QR-GARCH model. Using daily data of KOSPI stocks, this paper provides some empirical evidence for strong and volatile herding among traders of stocks of medium firms, and shows that time-varying herd behavior in traders of some stocks has persistent autocorrelation.

Electronic Attendance System Using Smart Device and High Frequency Signal

  • Myoungbeom Chung
    • Journal of the Korea Society of Computer and Information
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    • v.28 no.11
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    • pp.103-111
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    • 2023
  • Recently, many universities have used various electronic attendance systems such as NFC, QR code, Sound-QR, Bluetooth BLE authentication, and face recognition to process attendance. However, existing methods have various problems such as attendance errors due to deformation of authentication signals, mis-recognition attendance from outside the classroom, and difficulty to process seat absence during class. Therefore, this study proposes a high-frequency signal-based electronic attendance system to solve these problems and manage more accurate electronic attendance. As the high-frequency signal replaces the BLE signal, and the transmission range of the signal is limited to the classroom, and the signal value can be immediately changed if a change of the signal is needed. To verify the performance of the proposed system, we conducted a comparative experiment with the Bluetooth based electronic attendance system, and as a result, the proposed method showed high accuracy. Thus, the proposed method will be a useful service that can be immediately used in smart device-based electronic attendance system.

A Study on the Efficient m-step Parallel Generalization

  • Kim, Sun-Kyung
    • Proceedings of the Korea Society of Information Technology Applications Conference
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    • 2005.11a
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    • pp.13-16
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    • 2005
  • It would be desirable to have methods for specific problems, which have low communication costs compared to the computation costs, and in specific applications, algorithms need to be developed and mapped onto parallel computer architectures. Main memory access for shared memory system or global communication in message passing system deteriorate the computation speed. In this paper, it is found that the m-step generalization of the block Lanczos method enhances parallel properties by forming m simultaneous search direction vector blocks. QR factorization, which lowers the speed on parallel computers, is not necessary in the m-step block Lanczos method. The m-step method has the minimized synchronization points, which resulted in the minimized global communications compared to the standard methods.

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A Basic Study of the application of Implicitly Restarted Arnoldi Method to the Small Signal Stability of Large Power Systems (Implicitly Restarted Arnoldi Method를 이용한 대형전력계통 소신호안정도 적용 기초 연구)

  • Kim, D.J.;Moon, Y.H.
    • Proceedings of the KIEE Conference
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    • 2005.07a
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    • pp.393-395
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    • 2005
  • This paper describes implicitly restarted Arnoldi method (IRAM), which is a technique for combining the implicitly shifted QR mechanism with a k-step Arnoldi factorization to obtain a truncated form of the implicitly shifted QR-iteration. IRAM avoids numerical difficulties and storage problems normally associated with Arnoldi. This paper deals with the basic algorithms of IRAM as an intial research phase for developing the full featured eigenvalue analysis program for large power system up to 30,000 states.

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