• Title/Summary/Keyword: Multi-user

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User-created multi-view video generation with portable camera in mobile environment (모바일 환경의 이동형 카메라를 이용한 사용자 저작 다시점 동영상의 제안)

  • Sung, Bo Kyung;Park, Jun Hyoung;Yeo, Ji Hye;Ko, Il Ju
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.1
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    • pp.157-170
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    • 2012
  • Recently, user-created video shows high increasing in production and consumption. Among these, videos records an identical subject in limited space with multi-view are coming out. Occurring main reason of this kind of video is popularization of portable camera and mobile web environment. Multi-view has studied in visually representation technique fields for point of view. Definition of multi-view has been expanded and applied to various contents authoring lately. To make user-created videos into multi-view contents can be a kind of suggestion as a user experience for new form of video consumption. In this paper, we show the possibility to make user-created videos into multi-view video content through analyzing multi-view video contents even there exist attribute differentiations. To understanding definition and attribution of multi-view classified and analyzed existing multi-view contents. To solve time axis arranging problem occurred in multi-view processing proposed audio matching method. Audio matching method organize feature extracting and comparing. To extract features is proposed MFCC that is most universally used. Comparing is proposed n by n. We proposed multi-view video contents that can consume arranged user-created video by user selection.

Multi user interference cancellation in satellite to ground uplink system Based on improved WPIC algorithm

  • Qingyang, Guan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.11
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    • pp.5497-5512
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    • 2016
  • An improved optimal weights based on parallel interference cancellation algorithm has been proposed to cancel for interference induced by multi-user access satellite to ground uplink system. Due to differences in elevation relative motion between the user and the satellite, as well as access between users, resulting in multi-user access interference (Multi-user Access Interference, MUI), which significantly degrade system performance when multi-user access. By steepest gradient method, it obtained based on the MMSE criterion, parallel interference cancellation adjust optimal weights to obtain the maximum SINR. Compared to traditional parallel interference cancellation (Parallel Interference Cancellation, PIC) algorithm or serial interference cancellation ( Successive interference Cancellation, SIC), the accuracy of which is not high and too many complex iterations, we establish the multi-user access to the satellite to ground up link system to demonstrate that the improved WPIC algorithm could be provided with high accuracy and relatively low number of iterations.

인터넷 웹기반 가상강의 홈페이지 자동개설 툴킷의 구현

  • 곽재홍;김정헌;최재원
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 1999.11a
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    • pp.372-378
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    • 1999
  • The main purpose of this paper is a study on the automatically implementing a Multi user server education system and homepage via web browser from toolkit embedded Multi user server unix server Perl programming language and c language was used to make this toolkit. With using window based web browsers, the user can make they own classroom homepage. In this paper, we propose the single user server version and Multi user server version of this toolkit. With use of ftp, the Multi user server version of this toolkit can make homepage to other unix server workstation

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Joint Transmitter and Receiver Design Based on SPPLNR for Multi-user MIMO Channel with Channel Estimation Error (채널 추정 오차가 있는 다중사용자 다중안테나 채널에서 신호 대 포스트-프로세싱 리키지 및 잡음비 기반 송신기와 수신기 결합 설계)

  • Seo, Dong-Joon;Lee, Pan-Hyung;Lee, Jae-Hong
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.46 no.2
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    • pp.53-59
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    • 2009
  • In multi-user MIMO systems, a base station transmits multiple data to multi-user simultaneously in order to improve performance and bandwidth efficiency. When the base station transmits multiple data to multi-user simultaneously, multi-user interference occurs severely. In this paper, we define a post-processing leakage as the total power leaked from desired user to all other users after combining at the output of each user. Using concept of the post-processing leakage, we also define a performance metric, the so called signal-to-post-processing-leakage-plus-noise ratio (SPPLNR). Assuming that the receiver is the minimum mean square error (MMSE) receiver, we propose an iterative SPPLNR-based beamforming that determines beamforming vectors and combining vectors by using an iterative method. The proposed scheme does not impose a condition on the relation between the number of transmit antennas for the base station and the number of receive antennas for users. Simulation results show that the proposed scheme outperforms a beamforming scheme perfectly eliminating the multi-user interference when channel estimation error exists.

An Extended Multi-Server-Based User Authentication and Key Agreement Scheme with User Anonymity

  • Li, Chun-Ta;Lee, Cheng-Chi;Weng, Chi-Yao;Fan, Chun-I
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.1
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    • pp.119-131
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    • 2013
  • With the explosive growth of computer networks, many remote service providing servers and multi-server network architecture are provided and it is extremely inconvenient for users to remember numerous different identities and passwords. Therefore, it is important to provide a mechanism for a remote user to use single identity and password to access multi-server network architecture without repetitive registration and various multi-server authentication schemes have been proposed in recent years. Recently, Tsaur et al. proposed an efficient and secure smart card based user authentication and key agreement scheme for multi-server environments. They claimed that their scheme satisfies all of the requirements needed for achieving secure password authentication in multi-server environments and gives the formal proof on the execution of the proposed authenticated key agreement scheme. However, we find that Tsaur et al.'s scheme is still vulnerable to impersonation attack and many logged-in users' attack. We propose an extended scheme that not only removes the aforementioned weaknesses on their scheme but also achieves user anonymity for hiding login user's real identity. Compared with other previous related schemes, our proposed scheme keeps the efficiency and security and is more suitable for the practical applications.

Energy Efficient Transmit and Receive Strategy for Green Communications: K users extension

  • Oh, Changyoon
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.10
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    • pp.37-42
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    • 2016
  • We investigate multi user joint rate scheduling and power allocation problem for a delay sensitive CDMA systems. First, we characterize the existing two user joint rate scheduling and power allocation. We then extend the problem to the case of the multi user systems. In general, there is no simple optimum solution for the multi user scheduling problem. To that end, we propose a sub optimum solution, termed 'virtual user approach'. We show the performance of the virtual user approach to verify the benefit of complexity.

Performance Analysis of Multi-channel Joint Detection for CDMA in Multi-path Fading Channel (다중경로 페이딩 채널에서의 CDMA 다중채널 결합 검출 방식의 성능 분석)

  • 황용선;이종훈;김동구
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.8A
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    • pp.1099-1106
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    • 1999
  • In this paper, the bit error ratio(BER) performance of multi-carrier CDMA system in multi-user/multi-path environment is analytically derived, and effect of interferences due to multi-user, multi-carrier, multi-path is analyzed. A multi-carrier/multi-user/multi-path joint detection scheme incorporating a decorrelating detector is proposed, and its performance as well as the enhancement of noise due to decorrelating process are analyzed. BER of the proposed joint detection scheme is only slightly degraded compared to the ideal case of single user environment.

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A Research of User Experience on Multi-Modal Interactive Digital Art

  • Qianqian Jiang;Jeanhun Chung
    • International Journal of Internet, Broadcasting and Communication
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    • v.16 no.1
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    • pp.80-85
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    • 2024
  • The concept of single-modal digital art originated in the 20th century and has evolved through three key stages. Over time, digital art has transformed into multi-modal interaction, representing a new era in art forms. Based on multi-modal theory, this paper aims to explore the characteristics of interactive digital art in innovative art forms and its impact on user experience. Through an analysis of practical application of multi-modal interactive digital art, this study summarises the impact of creative models of digital art on the physical and mental aspects of user experience. In creating audio-visual-based art, multi-modal digital art should seamlessly incorporate sensory elements and leverage computer image processing technology. Focusing on user perception, emotional expression, and cultural communication, it strives to establish an immersive environment with user experience at its core. Future research, particularly with emerging technologies like Artificial Intelligence(AR) and Virtual Reality(VR), should not merely prioritize technology but aim for meaningful interaction. Through multi-modal interaction, digital art is poised to continually innovate, offering new possibilities and expanding the realm of interactive digital art.

An User Selection Scheme Enhancing Cell Capacity for Multi-user MIMO Channel Environment (다중 사용자 MIMO 채널 환경에서 셀 용량을 증가시키는 사용자 선택 기법)

  • Chung, Jae-Ho;Choi, Seung-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.1C
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    • pp.22-27
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    • 2011
  • This paper proposes an efficient user selection algorithm that provides a maximum 셀 용량 based Multi-user MIMO system based on zero-forcing criterion. The proposed scheme forms a primary group of users whose channel power exceeds a predetermined threshold. Through computer simulations, we have found that the proposed method outperforms the conventional scheme yielding a sum rate that is 0.33 bps/Hz higher when the total numbers of users and transmit antennas in the cell are 100 and 4, respectively.

Dynamic Feedback Selection Scheme for User Scheduling in Multi-user MIMO Systems (다중 사용자 MIMO 시스템의 사용자 스케쥴링을 위한 동적 피드백 선택 기법)

  • Kim, I-Cheon;Kang, Chung G.
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.4
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    • pp.646-652
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    • 2015
  • In this paper, the system-level performance is evaluated for the feedback scheme on the pre-coding matrix index (PMI) and channel quality indication (CQI), which are required for user selection in the multi-user MIMO system. Our analysis demonstrates that the number of users, the number of selected users, and codebook size are the key factors that govern the performance of the best companion grouping (BCG)-based user scheduling. Accordingly, we have confirmed that the probability of forming the co-scheduled user group is determined by these factors, which implies that the number of PMI's and codebook size can be dynamically determined so as to maximize the average system throughput as the number of users varies in the cell.