• Title/Summary/Keyword: Journal of Communication

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Performance Analysis of Hybrid SIMO-RF/FSO Communication System with Fixed Gain AF Relay

  • Shi, Wenxiao;Kang, Kai;Wang, Zhuo;Liu, Wei
    • Current Optics and Photonics
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    • v.3 no.5
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    • pp.365-373
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    • 2019
  • This paper investigates the performance of a hybrid single input multiple output radio frequency/free-space optics (SIMO-RF/FSO) communication system. Each SIMO-RF link is modeled as an independent and identically distributed (i.i.d.) Rayleigh distribution, while the FSO link follows a generalized $M{\acute{a}}laga$ (M) distribution. Considering the fixed gain amplify-and-forward (AF) relay and misalignment errors, novel expressions for the outage probability (OP), average bit error rate (ABER) and average capacity are derived. Numerical results show that atmospheric turbulence and misalignment errors can seriously impair the system performance, and the hybrid RF/FSO communication system using SIMO-RF links can greatly improve system performance. We also analyze system performance under different types of modulation schemes. Numerical results are verified by Monte Carlo simulations.

Implementation of a Fragmentation Method for Flow Control in Underwater Multi-media Communication (수중 다중 매체 통신의 흐름제어를 위한 단편화 기법 구현)

  • You, Dongsun;Shin, DongHyun;Lim, Seungsoo;Jeon, Seonghyun;Kim, Changhwa
    • Journal of Korea Multimedia Society
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    • v.23 no.7
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    • pp.819-829
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    • 2020
  • Underwater communication is necessarily useful for various application domains such as saving of human lives from underwater disasters, marine resource exploration, underwater military fields, underwater environment or ecosystem monitoring, fish farm monitoring and management, etc. Even though the acoustic wave has been the main underwater communication media until now, several media such as optical waves, VLF/ELF waves, magnetic fields, and infrared rays also began to be treated as possible media for underwater communication. If these underwater communicate-possible media are used mixing together, the underwater communication can be much more reliable and efficient through complementing the disadvantages of each communication media with advantages of other communication media. In fact, mixing and using multi-media for underwater communication requires the data flow control in the connection process of different media due to their communication speed gaps and bandwidth differences, and, specially, in the flow control, the appropriate message fragmentation technique is required inevitably. For this reason, this paper presents a fragmentation framework and technique necessary to the flow control in the underwater multi-media communication. In addition, through its implementation and experiments, this paper shows the feasibility on the realization of the multi-media based underwater communication.

The Analysis of Effects of LED Panel Position and Lighting Angle on Communication Channel Quality in Indoor Visible Light Communication Systems (살내 가시광 무선 통신 시스템에서 LED 패널 위치 및 발광 각도가 통신 채널 품질에 미치는 영향 분석)

  • Do, Tronghop;Hwang, Jun-Ho;Yoo, Myung-Sik
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.9B
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    • pp.1108-1116
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    • 2011
  • The visible light communication system that transmits data by controlling light emission of LED and receives data through photo detecter is considered as one of the strong candidates of the next generation wireless communication systems. The visible light communication provides both lighting and wireless communication wherever the LED lamps are installed. Due to the feature of visible light communication system, the communication is possible within the area that LED light reaches, and the communication quality depends on the light intensity received at the receiver. In this paper, we analyze the effects of LED panel position and lighting angel on communication channel quality in visible light communication systems. Through computer simulations, we prove that position of LED panel and light angle have a great impact on illuminance and SNR of the visible light communication systems.

A Study on the Activation Plan for the Communication Space of the Library According to Librarians' Perception Survey (도서관의 소통적 공간에 대한 사서 인식조사에 따른 활성화 방안 연구)

  • Noh, Younghee;Kim, Yoon-Jeong
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.31 no.4
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    • pp.5-27
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    • 2020
  • This study, as primary research that examines the communication characteristics of the library and the perception of librarians in order to make public libraries a communication space, surveyed the perception of librarians in public libraries and made an attempt to devise activation measures for the communication spaces of the library. As a result, the communication characteristics of the library were derived to be locality, community spirit, and interactivity. In addition, the perception survey found that librarians have positive remarks about the communication spaces of the library. As it shows a high degree of awareness, the library should focus on ways to revitalize communication. First, the direction of communication must be set in order to fulfill library's new role in communication and exchange. Second, it is desirable for the library to free itself from being a quiet space and recreate it as a space for communication. Third, the library needs to exchange and connect with organizations, groups, and gatherings of the community. Fourth, it seems necessary for the library to provide support for the users' independent and voluntary communication and operation of the community.

A Study on the Development Direction in Korea Marine Communication (우리나라의 해상통신의 발전방향에 관한 연구)

  • Shin, Hyun-Shik
    • The Journal of the Korea institute of electronic communication sciences
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    • v.3 no.3
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    • pp.143-152
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    • 2008
  • This thesis is what accident in sea have been produced as lost themselves life and property about 600~700times at every years. Therefore this was induced to experiment on a national basis that the role of communication of ship is to move from lose themselves life and property.

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Algorithms, Processes, and Services for Future ICT

  • Jeong, Young-Sik;Park, Jong Hyuk
    • Journal of Information Processing Systems
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    • v.16 no.6
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    • pp.1231-1237
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    • 2020
  • In recent years, future information and communication technology (ICT) has influenced and changed our lives. Without various ICT-based applications, we would have difficulty in securely storing, efficiently processing, and conveniently communicating information. In the future, ICT will play a very important role in the convergence of computing, communication, and all other computational sciences and application. ICT will also influence various fields including communication, science, engineering, industry, business, law, politics, culture, and medicine. In this paper, we investigate the latest algorithms, processes, and services in future fields.

A Study on Short-Range Wireless Communication System Development Using LED Based on Power Line Communication (전력선통신기반 LED를 이용한 단거리 무선통신 시스템 개발에 관한 연구)

  • Yun, Ji-Hun;Kim, Yong-Kab
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.3 no.1
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    • pp.19-23
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    • 2010
  • This study is to develop power line communication and short-range wireless communication system using LED. I will create optical receiver and transmitter using LED and optical sensor and connectors for display device and communication in receiver and transmitter were created. Experiment method is to signal and waveform through oscilloscope date from optical sensor after chosen a highly efficient LED. In addition, reception and transmitter of smoothly data using visible light communication program were checked. I will compliment problems through this experiment and constantly study, improve on power loss.

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A Kernel-Level Communication Module for Linux Clusters (리눅스 클러스터를 위한 커널 수준 통신 모듈)

  • 박동식;박성용;양지훈
    • Journal of KIISE:Computing Practices and Letters
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    • v.9 no.3
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    • pp.289-300
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    • 2003
  • Traditional kernel-level communication systems for clusters are dependent upon computing platforms. Futhermore, they are not easy to use and do not provide various functions for clusters. This paper presents an architecture and various implementation issues of a kernel-level communication system, KCCM(Kernel level Cluster Communication Module), for linux cluster. The KCCM provides asynchronous communication services as well as standard synchronous communication services using send and receive. The KCCM also automatically detects and recovers connection failures at runtime. This allows programmers to use KCCM when they build mission critical applications over TCP-based connection-oriented communication environments. Having developed using standard socket interfaces, it can be easily ported to various platforms. The experimental results show that the KCCM provides good performance for asynchronous communication patterns.

Distribution in Coworking Space: Exploring Brand Experience and Brand Image on Brand Equity through Brand Loyalty

  • Adzra Athira ARIEF;Indah PUSPITARINI;Farell Giovan ABRAHAMS;Ricardo INDRA;La MANI
    • Journal of Distribution Science
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    • v.22 no.7
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    • pp.13-22
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    • 2024
  • Purpose: This research is a quantitative study aimed at determining the influence of brand experience and brand image on brand equity through brand loyalty in the distribution in Coworking Space industry. Research design, data and methodology: The analytical method employed in this research is Partial Least Squares Structural Equation Modeling (PLS-SEM). The study utilizes a quantitative approach, with data collected through online questionnaires distributed via Google Forms among Coworking Space users. A total of 68 respondents represent the research population.. The data was analyzed using PLS-SEM to examine the relationships between the variables under investigation. Results: The research findings indicate that brand experience significantly affects both brand loyalty and brand equity. Similarly, brand image significantly influences both brand loyalty and brand equity. Additionally, brand loyalty has a significant impact on brand equity Conclusions: The research findings indicate that brand experience has a significant effect on brand loyalty and brand equity. Brand image significantly affects both brand loyalty and brand equity.Additionally, brand loyalty significantly influences brand equity.

The Communication study of The Tactical Communication Curriculum for Petty Officer in Community college (전문대학 부사관과의 전술적 의사소통을 통한 말하기 교육방안 연구)

  • Yu, Yong-tae
    • Convergence Security Journal
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    • v.17 no.4
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    • pp.53-62
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    • 2017
  • The goal of this study is to seek an educational method that bring major improvements of the tactical communication through setting a definition on the tactical communication and developing ways of the communication methods to petty officer majoring students in community college level. The study is formed a concept of the tactical communication based on the tactical soften influence and, set up three steps; Goal - Act - Achieving the purpose. The study clarifies that the tactical communication is formed by repeating three steps of 'Recognition - Understanding - Regarding - Act.' To suggest an efficient way of the tactical communication by reducing the repeating communication steps, the study proposes 'OODA loop' communication. The curriculum of Petty officer major students has three steps, Change - Apply - Present steps, with using the concept of 'OODA loop.' The curriculum method offers a way of improvement state on interpersonal and problem-solving abilities. This education method presents variety developed OODA loop situations to minimize the act step on conversing informations through objective perspective and helping faster decision making process.