• Smart Structures and Systems
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• v.24 no.5
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• pp.649-657
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• 2019

Recently, an advanced video deflectometer based on the principle of off-axis digital image correlation was presented and advocated for remote and real-time deflection monitoring of large engineering structures. In engineering practice, measurement accuracy is one of the most important technical indicators of the video deflectometer. However, it has been observed in many outdoor experiments that data drift often presents in the measured deflection-time curves, which is caused by the instability of imaging system and the unavoidable influences of ambient interferences (e.g., ambient light changes, ambient temperature variations as well as ambient vibrations) in non-laboratory conditions. The non-ideal unstable imaging conditions seriously deteriorate the measurement accuracy of the video deflectometer. In this work, to perform high-accuracy deflection monitoring, potential sources for the drift error are analyzed, and a drift error model is established by considering these error sources. Based on this model, a simple, easy-to-implement yet effective reference point compensation method is proposed for real-time removal of the drift error in measured deflections. The practicality and effectiveness of the proposed method are demonstrated by in-situ deflection monitoring of railway and highway bridges.

• Journal of KIISE:Computing Practices and Letters
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• v.7 no.6
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• pp.661-683
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• 2001

There is a rapid increase in the use of digital video information in recent years, it becomes more important to manage video databases efficiently. The development of high speed data network and digital techniques has emerged new multimedia applications such as internet broadcasting, Video On Demand(VOD) combined with video data processing and computer. Video database should be construct for searching fast, efficient video be extract the accurate feature information of video with more massive and more complex characteristics. Video database are essential differences between video databases and traditional databases. These differences lead to interesting new issues in searching of video, data modeling. So, cause us to consider new generation method of database, efficient retrieval method of video. In this paper, We propose the construction and generation method of the video database based on contents which is able to accumulate the meaningful structure of video and the prior production information. And by the proposed the construction and generation method of the video database implemented the video database which can produce the new contents for the internet broadcasting centralized on the video database. For this production, We proposed the video indexing method which integrates the annotation-based retrieval and the content-based retrieval in order to extract and retrieval the feature information of the video data using the relationship between the meaningful structure and the prior production information on the process of the video parsing and extracting the representative key frame. We can improve the performance of the video contents retrieval, because the integrated video indexing method is using the content-based metadata type represented in the low level of video and the annotation-based metadata type impressed in the high level which is difficult to extract the feature information of the video at he same time.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.2 s.302
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• pp.59-68
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• 2005

The amount of digitalized contents has been rapidly increased, but the main distribution channel of them is Internet which is easily accessible. Therefore 'security' necessarily arises as one of the most important issues and the method of protecting contents becomes a major research topic as much as data coding techniques. In recent years, many developers have studied on techniques that allow only authorized person to access contents. Among them the scrambling method is one of well-known security techniques. In this paper, we propose a simple and effective digital video scrambling method which utilizes the intra block properties of a recent video coding technique, H.264. Since intra prediction modes are adopted in H.264 standard, it is easy to scramble a video sequence with modification of the intra prediction modes. In addition to its simplicity, the proposed method does not increase bit rate after scrambling. The inter blocks are also distorted by scrambling intra blocks only. This paper introduces a new digital video scrambling method and verifies its effectiveness through simulation.

• Journal of Broadcast Engineering
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• v.16 no.3
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• pp.542-551
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• 2011

Recently an extension to DMB-AF (Digital Multimedia Broadcasting Application Format) standard was proposed in [1] without sufficient validation for industrial application due to incomplete implementation. The extended DMB-AF can include stereoscopic video and stereoscopic images for interactive service data, i.e., MPEG-4 BIFS data, in addition to the existing 2D video and 2D images for BIFS services. The contents in the extended DMB-AF can provide a temporal mixture of 2D/3D video presentations possibly with or without 2D/3D images for BIFS services. In this paper we developed DMB-AF player software that can play the extended DMB-AF files and authored several test files for its verification. As a result, we introduced a new method for indicating dependencies of 3D media tracks to improve the extension in [1] and validated the extended DMB-AF with the improvement.

• Journal of Digital Convergence
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• v.17 no.7
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• pp.207-214
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• 2019

This study was designed to find effective CPR education methods by comparing and analyzing the quality of Field-Focus Type (FFT) CPR using SimPad and the quality of Video Self-lnstruction(VSI) CPR for the learners. The data collection were conducted from November 28, 2018 to December 5, 2018, on 64 first graders who completed CPR lectures at universities located in G metropolitan city, and analyzed using the SPSS ver. 23.0. The results of the study, Field Focus Type (FFT) CPR showed higher quality of Video Self-lnstruction (VSI) CPR in areas such as CPR total score, chest compressions score, chest compressions dept, chest compressions rate, chest compression velocity, total ventilation score, and Total number of ventilation than that of the subjects. Therefore, using Field Focus Type CPR (FFT) education law was found to improve the quality of cardiopulmonary resuscitation compared to the existing Video Self-lnstruction CPR (VSI) education method, and it is believed that it can be used as a basic data for cardiopulmonary resuscitation education in the future.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.98.2-98
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• 2001

It is necessary to have enough transmission capacity for advanced internet techniques and various digital home appliances networking. Home appliances interface IEEE1394 technique has much wealthy transmission skill. IEEE1394 is using home appliances through various information form image and voice change data real time print out. In this paper, AVC CTS technology and IEEE1394 technology are introduced. Digital Video Camera includes compression format using DV. System composition control is consisted of protocols like IEC-61883 and AV/C command set standard.

• Journal of KIISE
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• v.45 no.3
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• pp.311-320
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• 2018

Recently, the use of digital audio and video as proof in criminal and all kinds of litigation is increasing, and scientific investigation using digital forensic technique is developing. With the development of computing and file editing technologies, anyone can simply manipulate video files, and the number of cases of manipulating digital data is increasing. As a result, the integrity of the evidence and the reliability of the evidence Is required. In this paper, we propose a technique for extracting the Electrical Network Frequency (ENF) through a grid of power grids according to the geographical environment for power supply, and then performing signal processing for peak detection using QIFFT. Through the detection algorithm using the standard deviation, it was confirmed that the video file was falsified with 73% accuracy and the forgery point was found.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2005.11a
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• pp.249-254
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• 2005

본 논문은 디지털 방송 프로그램 진행 중 비디오의 특정 시점에 동기화된 특정 객체의 위치정보를 표현하는 data stream을 생성하고, 그 시점에 해당 위치 정보를 해석하는 해석기에 관한 것이다. 현재의 상용 스트림 생성기는 디지털 방송 표준에서 권고하는 스트림 이벤트의 발생 시각과 셋톱박스에서 디코딩 시에 사용할 참조값을 적절하게 생성하지 못하고 있다. 또한, 셋톱박스에서 동작하는 애플리케이션(Xlet) 역시 STC(System Time Clock), PCR(Program Clock Reference), NPT(Normal Play Time) 등의 시간값을 적절하게 읽어내지 못하고 있다. 더욱이, 현재의 디지털 방송 표준에서는 영상 내 특정 객체를 위해 정보를 제공하는 데에는 한계가 있다. 따라서, 본 논문에서는 다양한 연동형 디지털 방송 프로그램 제작을 위해 비디오의 특정 시점에 동기화된 객체의 위치정보를 표현하는 data stream을 생성하는 방법과, 동기화된 데이터를 처리하는 애플리케이션에 대해서 설명한다.

• Journal of Broadcast Engineering
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• v.9 no.4 s.25
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• pp.411-423
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• 2004

In Korea, Eureka-147 DAB (Digital Audio Broadcasting) temporarily decided as the standard system for digital audio broadcasting was evolved into DMB (Digital Multimedia Broadcasting) to complement the technical vulnerability in mobile reception of terrestrial DTV. According to introducing video service in T-DMB (Terrestrial DMB), 'Terrestrial DMB Experimental Broadcasting for Video Service', a national project of the MIC (Ministry of Information and Communication), was done for verifying the possibility of video service via T-DMB. The main objective of the project is computing the effective field strength and coverage for making a plan to build T-DMB broadcasting network and developing transmitting and receiving equipment. In case of digital broadcasting, it is absolutely essential to measure BER (Bit Error Rate) and electric field strength in order to evaluate coverage and quality of received signal. In this paper, we implement an integrated mobile measurement system for T-DMB. For this purpose, we propose efficient data structure and algorithm for BER measurement. By adding GPS (Global Positioning System) and electric field strength measurement parts into BER measurement part, we complete the integrated mobile measurement system, and then verify it by experiments and field tests. The developed system was used in a national project, 'Terrestrial DMB Experimental Broadcasting for Video Service' and measurement results will be used as fundamental data for building T-DMB broadcasting network.

• Proceedings of the KOSOMBE Conference
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• v.1996 no.11
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• pp.304-306
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• 1996

Endoscopy has become a crucial diagnostic and theraputic procedure in clinical areas. Over the past three years, we have developed a computerized system to record and store clinical data pertaining to endoscopic surgery of laparascopic cholesystectomy, peviscopic endometriosis, and surgical arthroscopy. In this study, we are developed computer system, which is composed of frame grabber, sound board, VCR control board, LAN card and EDMS(endoscopic data management software). Also, computer system has controled over peripheral instruments as a color video printer, video cassette recorder, and endoscopic input/output signals(image and doctor's speech). Also, we are developed one body system of camels control unit including an endoscopic miniature camera and light source. Our system offer unsurpassed image quality in terms of resolution and color fidelity. Digital endoscopic data management system is based on open architecture and a set of widely available industry standards, namely: windows 3.1 as a operating system, TCP/IP as a network protocol and a time sequence based database that handles both an image and drctor's speech synchronized with endoscopic image.