• Title/Summary/Keyword: Video communications

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A Study on PON-based Mobile Backhaul Using Network Coding (네트워크 코딩을 이용한 PON기반 무선백홀 연구)

  • Jung, Bokrae
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.2
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    • pp.275-280
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    • 2013
  • With rapidly growing mobile wireless services, the existing copper-based mobile backhaul technologies suffer from reaching the capacity limits. PON technologies is drawing attention as a key solution to replace the existing mobile backhaul technologies due to not only providing innovative network capacity but also cost-effective maintenance caused by the bandwidth gain from optical fibers. With a PON-based mobile backhaul, broadband wireless multimedia services such as a video conference and IPTV can be seamlessly provided. In this paper, we first introduce overview of the PON-based mobile backhaul technology. For a example of practical integration, three types of EPON-WiMAX integrated architectures are proposed and comparatively analyzed in term of costs and network performance. Then, applicable plan and anticipated effects are presented when applying network coding on the PON-based mobile backhaul to improve the performance of delivering multicast traffic.

Development of the EPG Provider System based on DAB (DAB 기반의 EPG Provider 시스템 개발)

  • Jin Hyun-Joon;Park Nho-Kyung;Hwang Woon-Jae
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.41 no.12
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    • pp.51-60
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    • 2004
  • DAB(Digital Audio Broadcasting) is a new media service that can provide CD quality audio, various data service, interactive and high quality mobile communications through popular media such as terrestrial broadcasting, satellite, cable TV, and internet. In this paper, a new EPG(Electronic Program Guide) application model is proposed. The model is based on DAB and combines a DAB receiver and PCs so that it can take advantages of using various multimedia services and plenty of internet contents. The developed EPSD(EPG Provider System on DAB) has Web-based Server/Client structure and povides EPG functionalities to client PCs over internet. Therefore, the DAB receiver can be smaller and cheaper, and can develop abundant data services on internet. It can also provide high quality video services and be expected to become an important component in future home network systems.

Analysis of HEMP Coupling Signal for a Coaxial Cable with Braided Shields (Braided Shield를 가진 동축 케이블의 HEMP 결합 신호 해석)

  • Lee, Jin-Ho;Cho, Jea-Hoon;Kim, Eung-Jo
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.22 no.8
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    • pp.790-796
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    • 2011
  • The system which is exposed in the impact range of High-altitude Electromagnetic Pulse(HEMP) may get serious damage because HEMP has a very large electric field value, a very fast rise-time, and so on. Electromagnetic analysis should be performed for signals coupled to the opening or cables of the system prior to derive the system design specifications in order to protect the system against HEMP adequately. In this paper, we analyzed the HEMP coupled signals for the coaxial cable which is generally used to transmit and receive video or RF signals and compared the coupled signal of the one wire with that of the inner conductor of a coaxial cable to confirm the decreased effect of HEMP by the shield. The coaxial cable is analyzed by the external and internal region of the shield separately. For the external region of the coaxial cable, general scattered equation was applied to calculate currents on the surface of the shield and for internal region of the coaxial cable, chain matrix algorithm is used. To verify this paper the analyzed results were compared the results of the existing paper and the two results have good agreements.

Cancer Care Management through a Mobile Phone Health Approach: Key Considerations

  • Mohammadzadeh, Niloofar;Safdari, Reza;Rahimi, Azin
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.9
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    • pp.4961-4964
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    • 2013
  • Greater use of mobile phone devices seems inevitable because the health industry and cancer care are facing challenges such as resource constraints, rising care costs, the need for immediate access to healthcare data of types such as audio video texts for early detection and treatment of patients and increasing remote aids in telemedicine. Physicians, in order to study the causes of cancer, detect cancer earlier, act in prevention measures, determine the effectiveness of treatment and specify the reasons for the treatment ineffectiveness, need to access accurate, comprehensive and timely cancer data. Mobile devices provide opportunities and can play an important role in consulting, diagnosis, treatment, and quick access to health information. There easy carriage make them perfect tools for healthcare providers in cancer care management. Key factors in cancer care management systems through a mobile phone health approach must be considered such as human resources, confidentiality and privacy, legal and ethical issues, appropriate ICT and provider infrastructure and costs in general aspects and interoperability, human relationships, types of mobile devices and telecommunication related points in specific aspects. The successful implementation of mobile-based systems in cancer care management will constantly face many challenges. Hence, in applying mobile cancer care, involvement of users and considering their needs in all phases of project, providing adequate bandwidth, preparation of standard tools that provide maximum mobility and flexibility for users, decreasing obstacles to interrupt network communications, and using suitable communication protocols are essential. It is obvious that identifying and reducing barriers and strengthening the positive points will have a significant role in appropriate planning and promoting the achievements of mobile cancer care systems. The aim of this article is to explain key points which should be considered in designing appropriate mobile health systems in cancer care as an approach for improving cancer care management.

A Study on the 3-D Stereoscopic Video Techniques Using Motion Typography (모션 타이포그래피를 이용한 3차원 입체영상 제작방법에 관한 연구)

  • Lee, Jun-Sang;Park, Sung-Dae;Kim, Chee-Yong;Han, Soo-Whan
    • Journal of Korea Multimedia Society
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    • v.14 no.8
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    • pp.1070-1081
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    • 2011
  • Among visual communications methods through new media, the typography becomes a key role in information transfer areas with the development of motion graphics. Recently, the researches on stereoscopic image productions have been carried out actively to increase the reality of created images, and the various new approaches for the production of stereoscopic images have been investigated. However, it is obvious that the researches using motion typography have not been studied sufficiently. Thus in this study, the stereoscopic images for moving typography are suggested and produced by using three experimental studies -- the experiments using text movement, camera movement, and finally, editing and composition. In the experiments, from the stereoscopic motion typography produced by our proposed methods, the various visual effects have been obtained, and the visual communication with high reality has been achieved.

An Orthogonal Approximate DCT for Fast Image Compression (고속 영상 압축을 위한 근사 이산 코사인 변환)

  • Kim, Seehyun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.10
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    • pp.2403-2408
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    • 2015
  • For image data the discrete cosine transform (DCT) has comparable energy compaction capability to Karhunen-Loeve transform (KLT) which is optimal. Hence DCT has been widely accepted in various image and video compression standard such as JPEG, MPEG-2, and MPEG-4. Recently some approximate DCT's have been reported, which can be computed much faster than the original DCT because their coefficients are either zero or the power of 2. Although the level of energy compaction is slightly degraded, the approximate DCT's can be utilized in real time implementation of image or visual compression applications. In this paper, an approximate 8-point DCT which contains 17 non-zero power-of-2 coefficients and high energy compaction capability comparable to DCT is proposed. Transform coding experiments with several images show that the proposed transform outperforms the published works.

An Efficient Algorithm of Network Bandwidth Allocations for Multimedia Services (멀티미디어 서비스를 위한 효율적인 대역폭 할당)

  • 김정택;고인선
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.11C
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    • pp.1112-1123
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    • 2002
  • Providing a multimedia service requires efficient network bandwidth allocation scheduling. Typically, transmission of information with bursty characteristics, such as a video data stream, utilizes some type of smoothing technique that reduces the transmission rate fluctuation. While capable of a drastic reduction in the peak transmission rate, even the optimum smoothing algorithm proposed to date, however, is rather inadequate for multi-stream applications that share network bandwidth since such an algorithm has been designed and applied toward handling each independent stream. In this paper, we proposed an efficient bandwidth allocation algorithm that addresses these shortcomings. The proposed bandwidth allocation algorithm is divided into two steps, a static bandwidth allocation and a dynamic bandwidth allocation. In the former case, the peak rate reduction is achieved by maintaining the accumulated data in the user buffer at a high level, whereas the concept of real demand factor is employed to meet the needs of multi-stream bandwidth allocation in the latter case, Finally, the proposed algorithm's performance was verified with ExSpect 6.41, a Petri net simulation tool.

A Study on Implementation of the Fast Motion Estimation (고속 움직임 예측기 구현에 관한 연구)

  • Kim, Jin-Yean;Park, Sang-Bong;Jin, Hyun-Jun;Park, Nho-Kyung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.1C
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    • pp.69-77
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    • 2002
  • Sine digital signal processing for motion pictures requires huge amount of data computation to store, manipulate and transmit, more effective data compression is necessary. Therefore, the ITU-T recommended H.26x as data compression standards for digital motion pictures. The data compression method that eliminates time redundancies by motion estimation using relationship between picture frames has been widely used. Most video conding systems employ block matching algorithm for the motion estimation and compensation, and the algorithm is based on the minimun value of cast functions. Therefore, fast search algorithm rather than full search algorithm is more effective in real time low data rates encodings such as H.26x. In this paper, motion estimation employing the Nearest-Neighbors algorithm is designed to reduce search time using FPGA, coded in VHDL, and simulated and verified using Xilink Foundation.

Fast Mode Decision Algorithm Using Efficient Block Skip Techniques for H.264 P Slices (효율적인 블록 스킵 기술들을 이용한 H.264에서의 고속 모드 결정 알고리즘)

  • Jo, Young-Sub;Jeong, Je-Chang
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.2C
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    • pp.193-202
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    • 2010
  • In this paper, we propose a fast algorithm that can reduce the complexity for inter mode decision of the H.264 encoder. The main idea consists of two techniques. The first one is the technique early terminating mode decision process. We focused on the skip and $16{\times}16$ mode because these modes occupies the largest portion in most of sequences. The second one is the technique skipping unnecessary $8{\times}8$ modes. The time consumption caused by the $8{\times}8$ mode is very considerable. Therefore if we can extract the unnecessary $8{\times}8$ mode calculation well, a large amount of time can be saved in total encoding process. The experimental results show that the proposed algorithm can achieve up to 43% speed up ratio with insignificant PSNR loss. The increase of total bits encoded is also not noticeable.

Design and Implementation of Hand-Held Inspection Device for High Performance Mobile TFT LCD/OLED Module (고성능 모바일 TFT LCD/OLED 모듈을 위한 헨드헬드 검사장비 설계 및 구현)

  • Moon, Seung-Jin;Kim, Hong-Kyu
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.6B
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    • pp.630-640
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    • 2009
  • The thesis suggests hand-held equipment to overhaul for mobile TFT LCD/OLED module of high-performance. The established module equipment to overhaul could distinguish outputting video data to module for distinguishing flicker, but it is impossible with low system. In this thesis, supporting system could check the various supplement functions from bringing equipment to overhaul without changing design of FPGA or H/W the module various size for equipment to overhaul for module of high-performance coincidently. The system includes hand-held equipment to overhaul, test software embedded and software a base personal computer and have designed to output, save, and certify all contents of module test of hand-held equipment to overhaul to interface universal serial bus. Setting up 9 items that represent for efficient verification of the proposed system have been possible confirmation with TFT LCD/OLED module of high-performance, establishment scan time, creation gamma, changing register, supporting interface, and multi inch modules.