• Title/Summary/Keyword: Video communication

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e-Learning Contents Development as Social Negotiation Perspective: A Case Study of Program Development for the Public Sector Officials' Case Management (사회적 협상 관점의 e-Learning 콘텐츠 개발: 사례관리 담당 공무원을 위한 프로그램 개발 사례연구)

  • Kim, In-Sook;Jin, Sun-Mee
    • The Journal of the Korea Contents Association
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    • v.11 no.7
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    • pp.519-527
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    • 2011
  • The e-Learning program is a multimedia data program consisting of texts, images, animation, audio and video. The development of an e-Learning program requires time and is a complex process, requiring cooperation and open-communication between all parties involved, particularly in the event of a problem. This study will analyze the e-Learning contents development process from the Social Negotiation Perspective. An appropriate process for the development of the program and effective decision-making guidelines for those parties involved will be recommended. Participants' viewpoints regarding program development and guidelines were studied qualitatively, while the evaluation of developed content employed both qualitative and quantitative research. The study found the following results. First, the development of an e-Learning program requires a clear goal and purpose. Second, the target group must be clearly identified. Third, all parties involved must share in the development process and its outcomes. Fourth, the party requesting the program must allocate the appropriate time and budget for the development group. Finally, the project requires a strong, capable leadership for effective decision-making.

Design and Implementation of Buffer Cache for EXT3NS File System (EXT3NS 파일 시스템을 위한 버퍼 캐시의 설계 및 구현)

  • Sohn, Sung-Hoon;Jung, Sung-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.12
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    • pp.2202-2211
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    • 2006
  • EXT3NS is a special-purpose file system for large scale multimedia streaming servers. It is built on top of streaming acceleration hardware device called Network-Storage card. The EXT3NS file system significantly improves streaming performance by eliminating memory-to-memory copy operations, i.e. sending video/audio from disk directly to network interface with no main memory buffering. In this paper, we design and implement a buffer cache mechanism, called PMEMCACHE, for EXT3NS file system. We also propose a buffer cache replacement method called ONS for the buffer cache mechanism. The ONS algorithm outperforms other existing buffer replacement algorithms in distributed multimedia streaming environment. In EXT3NS with PMEMCACHE, operation is 33MB/sec and random read operation is 2.4MB/sec. Also, the buffer replacement ONS algorithm shows better performance by 600KB/sec than other buffer cache replacement policies. As a result PMEMCACHE and an ONS can greatly improve the performance of multimedia steaming server which should supportmultiple client requests at the same time.

Application-Services, "Islands" utilizing web-picture (웹 영상을 활용한 "섬"앱 서비스에 관한 연구)

  • Kwon, Oh-Tae;Kang, Hyo-Soon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.12
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    • pp.2712-2716
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    • 2011
  • The development of mobile phone is growing everyday according to the change of our age. Most of all, the birth of smart phone has gotten lots of attentions. The Smart Phone has not only nalogue functions for calling and receiving but also has many multiple-service functions satisfying the contemporary digital needs. Due to the smart phone, people could access to various and plenty information simply by touching it. It was Sep. 2011 that the number of smart phone users began to be more than 15,000,000. That number stands for the turning point of digital revolution. In Korea, both of "Omnia" from Samsung and "i-phone" from Apple came into the market near the end of 2009. That time was so called the full-scale first smart-phone war, and thinking of the time, it could be named as the explosive growth of smart phones. We can predict that the smart phone will influence the real life of human beings not only the mobile phone market. In this way, the smart phone has come deeply into our life day by day. For instance, more people can be able to get the informations of their trip for their leisure and free weekends through the smart phone. Thus, our study, began with the theme of "Korean islands trip", will start in the relationship with the Application-Services, "Islands" utilizing web-pictures.

A New Secure Multicast Protocol in Micro-Mobility Environments using Secure Group Key (마이크로 모빌리티 환경에서 보안 그룹키를 이용한 안전한 멀티캐스트 프로토콜)

  • Kang, Ho-Seok;Shim, Young-Chul
    • The KIPS Transactions:PartC
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    • v.15C no.6
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    • pp.573-586
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    • 2008
  • The improved performance and miniaturization of computer and the improvement of wireless communication technology have enabled the emergence of many high quality services. Among them multicast services are receiving much attention and their usage is increasing due to the increase of Internet multimedia services such as video conference, multimedia stream, internet TV, etc. Security plays an important role in mobile multicast services. In this paper, we proposed a secure multicast protocol for a hierarchical micro-mobility environment. The proposed secure multicast protocol provides security services such as authentication, access control, confidentiality and integrity using mechanisms including symmetric/asymmetric key crypto-algorithms and capabilities. To provide forward/backward secrecy and scalability, we used sub-group keys based on the hierarchical micro-mobility environment. With this security services, it is possible to guard against all kinds of security attacks performed by illegal mobile nodes. Attacks executed by internal nodes can be thwarted except those attacks which delete packet or cause network resources to be wasted. We used simulator to measure the performance of proposed protocol. As a result, the simulation showed that effect of these security mechanisms on the multicast protocol was not too high.

Self-Diagnosing Disease Classification System for Oriental Medical Science with Refined Fuzzy ART Algorithm (Refined Fuzzy ART 알고리즘을 이용한 한방 자가 질병 분류 시스템)

  • Kim, Kwang-Baek
    • The Journal of the Korea Contents Association
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    • v.9 no.7
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    • pp.1-8
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    • 2009
  • In this paper, we propose a home medical system that integrates a self-diagnosing disease classification system and a tele-consulting system by communication technology. The proposed disease classification system supports to self-diagnose the health condition based on oriental medical science using fuzzy neural network algorithm. The prepared database includes 72 different diseases and their associated symptoms based on a famous medical science book "Dong-eui-bo-gam". The proposed system extracts three most prospective diseases from user's symptoms by analyzing disease database with fuzzy neural network technology. Technically, user's symptoms are used as an input vector and the clustering algorithm based upon a fuzzy neural network is performed. The degree of fuzzy membership is computed for each probable cluster and the system infers the three most prospective diseases with their degree of membership. Such information should be sent to medical doctors via our tele-consulting system module. Finally a user can take an appropriate consultation via video images by a medical doctor. Oriental medical doctors verified the accuracy of disease diagnosing ability and the efficacy of overall system's plausibility in the real world.

China's Post '80s and '90s Generation and Selective Reception of Foreign Popular Culture: The Case of Beijing (중국 80-90후(后)와 외국 대중문화의 선택적 수용: 베이징 사례)

  • Ahn, Jungah
    • The Journal of the Korea Contents Association
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    • v.14 no.6
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    • pp.34-43
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    • 2014
  • Young Chinese audience can select and watch TV dramas, movies and entertainment programs from many different nations, such as Korea, America, Japan, England, Thailand, India, and so on, through multiple channels, such as online video sites - iQiyi, Youku, LeTV, PPTV, and many others - which were induced by changes in media environment. Various genres of Korean popular culture have recently become popular in China, but this phenomenon differs from the early Korean Wave. During the earlier period (from 1997 to the early 2000s) of the Korean Wave, soap operas were popular among middle-aged women, but now various other genres, such as K-pop, entertainment programs, etc., are also popular in China. The purpose of this study is to explore how young Chinese audiences use foreign pop culture, including their preferred genres, reasons for preferring these genres, and the relationship between the preferred pop culture and national image in Korean, American, and Japanese pop culture were analyzed. According to the study results, similarities and differences between preferred genres and the reasons for preferring these genres, and also a close correlation between preferred pop culture and national image were found. These findings will be fundamental for supporting the continual development of the Korean Wave in China.

Study On The Signal Radar Plan Position Indicator Scope Of The Data Expressed Scanning System Implemented As An Sticking Image On LCD Display (Plan Position Indicator Scope 주사방식의 Radar 영상신호를 LCD Display에 잔상영상으로 데이터 표출 구현에 관한 연구)

  • Shin, Hyun Jong;Yu, Hyeung Keun
    • Journal of Satellite, Information and Communications
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    • v.10 no.3
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    • pp.94-101
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    • 2015
  • The display device is an important video information communication system device to connect between human and device. it transfers the information as characters, shapes, images and pattern to enable recognizing by eyes. Theres absolutely needs some key functions and role to quickly display informations. It can analyse a information through a PPI Scope of a cathode-ray tube(CRT) displays information which can perform a role. this research proposed a radar device to display informations as received signal. The radar display researches can apply to fixed function graphics pipeline algorithms of the large capacity type through a vertical blanking interval and buffer swap of display unit. Also, it can be possible to apply to performed algorithms to FPGA logic without high-performance graphics processing unit GPU through synchronization which can implement a display system. In this paper, we improved the affordability and reliability through proposed research. 이So, we have studied the radar display unit which can change a flat display from radar display of CRT radar display.

An Efficient Broadcasting Channel Assignment Scheme for Mobile VOD Services (모바일 VOD 서비스를 위한 브로드캐스팅 채널할당 기법)

  • Choi, Young
    • Journal of Korea Multimedia Society
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    • v.11 no.5
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    • pp.685-691
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    • 2008
  • Recently with the rapid evolution of the mobile computing and communication technologies, mobile VOD service becomes increasingly important for wireless mobile users. The VOD service is being widely used in various areas of application, such as education, entertainment and business, because it provides users convenience in easily having access to video information at any time in any places. However, in reality, the mobile system has many difficulties in providing the smooth VOD service owing to frequent transfers and cutoffs of clients. The importance of a technique to transmit broadcasting is being stressed as a method for providing stabler mobile VOD service to a large number of clients. This paper is aimed at showing how to reduce demands for server bandwidth and delay of earlier service through performance analysis by suggesting an effective VOD broadcasting transmission technique through channel division in the mobile atmosphere. Many researches have been made about regular broadcasting techniques in particular. This study divides the methods used for assigning channels which have been decided by the size of segments into a group of regular channels and assistant channels using wireless gap-fillers to provide effective VOD services to a large number of clients at the mobile environment using small bandwidth resources. The regular channels transfer regular streams, while assistant channels repeatedly transfer the first segment to reduce early service delay time to receive regular streams. In this way, the study suggests a technique to reduce server bandwidth demand and early service delay time. Through the proposed technique, the server bandwidth demand could be reduced by more than 30 percent and the study continuously shows reduced early service delay time through conducting performance analysis.

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A Network-adaptive Context Extraction Method for JPEG2000 Using Tree-Structure of Coefficients from DWT (DWT 계수의 트리구조를 이용한 네트워크-적응적 JPEG2000 컨텍스트 추출방법)

  • Choi Hyun-Jun;Seo Young-Ho;Kim Dong-Wook
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.9C
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    • pp.939-948
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    • 2005
  • In EBCOT, the context extraction process takes excessive calculation time and this paper proposed a method to reduce this calculation time. That is, if a coefficient is less than a pre-defined threshold value the coefficient and its descendents skip the context extraction process. There is a trade-off relationship between the calculation time and the image quality or the amount of output data such that as this threshold value increases, the calculation time and the amount of output data decreases, but the image degradation increases. Therefore, by deciding this threshold value according to the network environments or conditions, it is possible to establish a network-adaptive context extraction method. The experimental results showed that the range of the threshold values for acceptable image quality(better than 30dB) is from 0 to 4. The experimental results showed that in this range the Resulting reduction rate in calculation time was from $3\%\;to\;64\%$ in average, the reduction rate in output data was from $32\%$ to $73\%$ in average, which means that large reduction in calculation time and output data can be obtained with a cost of an acceptable image quality degradation. Therefore, the proposed method is expected to be used efficiently in the application area such as the real-time image/video data communication in wireless environments, etc.

Peer-to-Peer Transfer Scheme for Multimedia Partial Stream using Client Initiated with Prefetching (멀티미디어 데이터를 위한 피어-투-피어 전송모델)

  • 신광식;윤완오;정진하;최상방
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.7B
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    • pp.598-612
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    • 2004
  • Client requests have increased with the improvement of network resources at client side, whereas network resources at server side could not keep pace with the increased client request. Therefore, it is primary factor of the Qos that efficiently utilize network resources at server side. In this paper, we proposed a new model that peer-to-peer transfer scheme for partial multimedia stream based on CIWP which it decrease server network bandwidth by utilizing client disk resources saves additional server network resources. Especially, adapting Threshold_Based Multicast scheme guarantees to do that data transfer within clients never exceed service time of previous peer by restriction of which data size transferring from previous peer less than data size transferring from server. Peer-to-peer transfer within clients is limited in same group classified as ISPs. Our analytical result shows that proposed scheme reduces appling network resources at server side as utilizing additional client disk resource. furthermore, we perform various simulation study demonstrating the performance gain through comparing delay time and proportion of waiting requesters. As a result, when we compared to Threshold_Based Multicast scheme, the proposed scheme reduces server network bandwidth by 35%.