• Title/Summary/Keyword: Multi-channel implementation

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A Study on Methods for Utilizing Digital Room in Public Library (공공도서관 디지털자료실 활성화 방안 연구)

  • Moon, Sung-Been;Kim, Pan-Jun;Lee, Mi-Kyeung
    • Journal of the Korean Society for information Management
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    • v.26 no.1
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    • pp.321-350
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    • 2009
  • The purpose of this study is to find methods for utilizing digital room in public library and its efficient operation by analyzing the status quo of the digital rooms in public libraries, which had been built nation-widely about 5 years ago. It is found that it is urgent to supplement and improve the infrastructure of them. It is also required to build multi-functional digital rooms and an integrated operational system for digital rooms. Implementation of an integrated operational system, first of all, for applicable sections of digital room may be the best alternative. The multi-functional digital rooms can be built, which, in addition to its traditional function, can include a variety of original information resources and function of information creation using application programs, as well as functions such as education, information services, online/offline community creation, and activating information sharing. In the future, the digital rooms in public libraries must play a significant role as online/offline spaces, which are not the places for use and access to internet information resource, but for information/knowledge sharing and collaborative activities. It also must provide a communication channel between librarians and users as well as among users themselves.

A Dual-Mode 2.4-GHz CMOS Transceiver for High-Rate Bluetooth Systems

  • Hyun, Seok-Bong;Tak, Geum-Young;Kim, Sun-Hee;Kim, Byung-Jo;Ko, Jin-Ho;Park, Seong-Su
    • ETRI Journal
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    • v.26 no.3
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    • pp.229-240
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    • 2004
  • This paper reports on our development of a dual-mode transceiver for a CMOS high-rate Bluetooth system-onchip solution. The transceiver includes most of the radio building blocks such as an active complex filter, a Gaussian frequency shift keying (GFSK) demodulator, a variable gain amplifier (VGA), a dc offset cancellation circuit, a quadrature local oscillator (LO) generator, and an RF front-end. It is designed for both the normal-rate Bluetooth with an instantaneous bit rate of 1 Mb/s and the high-rate Bluetooth of up to 12 Mb/s. The receiver employs a dualconversion combined with a baseband dual-path architecture for resolving many problems such as flicker noise, dc offset, and power consumption of the dual-mode system. The transceiver requires none of the external image-rejection and intermediate frequency (IF) channel filters by using an LO of 1.6 GHz and the fifth order onchip filters. The chip is fabricated on a $6.5-mm^{2}$ die using a standard $0.25-{\mu}m$ CMOS technology. Experimental results show an in-band image-rejection ratio of 40 dB, an IIP3 of -5 dBm, and a sensitivity of -77 dBm for the Bluetooth mode when the losses from the external components are compensated. It consumes 42 mA in receive ${\pi}/4-diffrential$ quadrature phase-shift keying $({\pi}/4-DQPSK)$ mode of 8 Mb/s, 35 mA in receive GFSK mode of 1 Mb/s, and 32 mA in transmit mode from a 2.5-V supply. These results indicate that the architecture and circuits are adaptable to the implementation of a low-cost, multi-mode, high-speed wireless personal area network.

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A Study on the $20^{th}$-century Korean Art History: Focusing on the 1960s-70s Art (20세기 한국미술사 연구를 위한 소고: 1960-70년대 미술을 중심으로)

  • Park, Choon Ho
    • The Journal of Art Theory & Practice
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    • no.16
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    • pp.7-40
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    • 2013
  • Historian Eric J. Hobsbawm once said "the task that historians have is to analyze the meanings of the past within the context of society and to track the changes and implementation." It would not be too far of a stretch to apply Hobsbawm's quote to art historian since art history, although quite specific, is still history. In addition, Hobsbaum also asserted that, "a mold called the past continuously forms the present or at least thought to be." It is my recognition that the major westernization of the last century took place under the Japanese colonization which served as the channel to usher in western art; however, the current 20thcentury Korean art history fails to recognize that the mold of the past, namely western art in this case, has formed the modern art of the present. Based on this recognition, attention was given to what lacked in the analysis of the current 20th-century Korean art history in terms of "Informel" which was identified as the turning point towards "modern art" in the Korean art history as well as the following "experimental art." My belief is that the art history of Korea has to be reassessed from, a socio-cultural perspective as well as adopting multi-level and diachronic understanding. However, the existing Korean art, especially the one between the end of 1950s to the 1970s was based on the perspective of "severance"; thus, raising the needs for the starting point of a new perspective. It is my conviction that meta perspective on writing is most essential in order to lay a solid basis for the Korean art scene to have a productive discussion. I feel the utmost necessity to reinterpret the typified history analysis and criticism which stemmed from the trauma under the Japanese colonization. The most urgent task is to avoid academic closeness and to share the research. Painting is an individual expression of the artist, but the act of expression is not free from the cultural and societal influence to which the artist belongs.

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Implementation of Adaptive Feedback Cancellation Algorithm for Multichannel Digital Hearing Aid (다채널 디지털 보청기에 적용 가능한 Adaptive Feedback Cancellation 알고리즘 구현)

  • Jeon, Shin-Hyuk;Ji, You-Na;Park, Young-Cheol
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.10 no.1
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    • pp.102-110
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    • 2017
  • In this paper, we have implemented an real-time adaptive feedback cancellation(AFC) algorithm that can be applied to multi-channel digital hearing aid. Multichannel digital hearing aid typically use the FFT filterbank based Wide Dynamic Range Compression(WDRC) algorithm to compensate for hearing loss. The implemented real-time acoustic feedback cancellation algorithm has one integrated structure using the same FFT filter bank with WDRC, which can be beneficial in terms of computation affecting the hearing aid battery life. In addition, when the AFC fails to operate due to nonlinear input and output, the reduction gain is applied to improve robustness in practical environment. The implemented algorithm can be further improved by adding various signal processing algorithm such as speech enhancement.

Conceptual Design on the ISDN Service Node for Multi-party Connection Services -Part II. A Study on the Control Procedures for the Service Node - (ISDN에서의 다자간 접속 서비스 제공을 위한 서비스노드의 개념적 설계 - 제2부 : 서비스노드 제어절차에 관한 연구 -)

  • 옥승수;강민석;조규섭;박병철
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.2
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    • pp.242-253
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    • 1994
  • For the implementation of a Service Node, which is proposed in the companion paper to provide multiparty conference type sevices in the ISDN, we define some technical aspects such as connection control, service control procedure and control messages in this paper. Additional connection control procedures for the multiparty connections are annexed to the CCITT Rec. Q.931 and Q.764 for the ISDN subscriber and common channel interoffice signaling. A new set of service control procedures is also established according to the necessary service control functions. The messages for these procedures are formatted using user-to-user signaling parts of Q.931 and Q.763 messages not to affect on the existing signaling system. Some technical requirements of subscriber terminal for the multiparty services are also deduced.

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Rate-Aware Two-Way Relaying for Low-Cost Ship-to-Ship Communications (저비용 선박간 통신을 위한 전송률 인지 양방향 릴레이 기법)

  • Wang, Jinsoo;Kim, Sun Yong;Jeong, Min-A;Lee, Seong Ro;Kim, Yun Hee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39C no.8
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    • pp.651-659
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    • 2014
  • In this paper, we consider a two way relay network for ship-to-ship communications in a fleet, where two communicating ships exchange the information with the help of a multi-antenna relay ship. For the network, we propose a rate-aware three-phase analog network coding to improve the reliability of the information exchange with asymmetric rates. The proposed scheme allows low-complex implementation of the relay without channel estimation by generating an improved analog network coded signal with the orthogonally received signals from two ships by using only the received signal power at each antenna. In addition, the proposed scheme reduces outages in the data exchange at asymmetric rates by adopting a rate-aware relay power allocation, which is confirmed by evaluating the outage performance via simulation.

Resource Allocation in Spectrum Sharing ad-hoc Cognitive Radio Networks Based on Game Theory: An Overview

  • Abdul-Ghafoor, Omar B.;Ismail, Mahamod;Nordin, Rosdiadee;El-Saleh, Ayman Abd
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.12
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    • pp.2957-2986
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    • 2013
  • The traditional approach of fixed spectrum allocation to licensed networks has resulted in spectrum underutilisation. Cognitive radio technology is envisioned as a promising solution that can be used to resolve the ineffectiveness of the fixed spectrum allocation policy by accessing the underutilised spectrum of existing technologies opportunistically. The implementation of cognitive radio networks (CRNs) faces distinct challenges due to the fact that two systems (i.e., cognitive radio (CR) and primary users (PUs)) with conflicting interests interact with each other. Specially, in self-organised systems such as ad-hoc CRNs (AHCRNs), the coordination of spectrum access introduces challenges to researchers due to rapid utilisation changes in the available spectrum, as well as the multi-hop nature of ad-hoc networks, which creates additional challenges in the analysis of resource allocation (e.g., power control, channel and rate allocation). Instead, game theory has been adopted as a powerful mathematical tool in analysing and modelling the interaction processes of AHCRNs. In this survey, we first review the most fundamental concepts and architectures of CRNs and AHCRNs. We then introduce the concepts of game theory, utility function, Nash equilibrium and pricing techniques. Finally, we survey the recent literature on the game theoretic analysis of AHCRNs, highlighting its applicability to the physical layer PHY, the MAC layer and the network layer.

The Application and Integration of an Improvement Technique for Layers of NETCONF (NETCONF 계층에 대한 개선 기법 적용 및 통합)

  • Lee, YangMin;Lee, JaeKee
    • Journal of KIISE
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    • v.43 no.2
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    • pp.256-268
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    • 2016
  • Modern networks consisting of various heterogeneous equipment are often installed in a distributed manner. Thus the NETCONF standard was established to manage networks centrally and efficiently. In this paper, we present a method that integrates each NETCONF layer into a single system based on the results of previous studies. In the RPC Layer, an asynchronous communication channel and parallel processes are possible using multi-threading. In the Operation Layer, operational efficiency is increased by using a data group with dependencies between the equipment configuration data and by improving the data structure, enabling efficiently processing of XML queries even with multiple managers. The data modeling techniques and grouping methods in the Content Layer are presented in detail for interoperability between the Operation Layer and the Content Layer. Finally, the GUI program was implemented and its implementation is reported. We performed an experiment comparing the improved NETCONF with the standard NETCONF to measure factors, such as query processing ratio, query processing speed, and CPU utilization. The improved NETCONF demonstrated excellent query processing ratio and query processing speed, whereas the standard NETCONF had excellent CPU utilization.

A Study on the IUU Governance System of Regional Fishery Management Organization and Major State (국제 지역 수산 관리 기구와 주요 국가의 IUU 통제제도 연구)

  • Park, Min-Gyu
    • The Journal of Fisheries Business Administration
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    • v.41 no.3
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    • pp.103-127
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    • 2010
  • The FAO reports that IUU fishing activities have widespread economic, social, and management consequences, including depriving legitimate fishers of harvest opportunities. It affects all fisheries from small scale to industrial. It also affects the ability of governments to support sustainable livelihoods for fishers and, more broadly, to achieve food security. The complexity of IUU requires various measures to combat IUU fishing such as adoption of IUU vessel lists; stronger port State controls; improved monitoring, control and surveillance (MCS); implementation of market-related measures to help ensure compliance; and capacity-building assistance. Trade and market measures reduce opportunities for IUU fishing activities by precluding or impeding access to markets for IUU product in a manner consistent with international law. ICCAT, CCAMLR, and IATTC, have put in place trade tracking programs or catch documentation schemes, and WCPFC is considering such a program. Vessel lists assist enforcement authorities in determining which vessels are or are not authorized to be fishing or conducting fishing support activities in specified areas. A number of RFMOs maintain records of IUU vessels: CCAMLR, IATTC, ICCAT, NAFO, NASCO, NPAFC, WCPFC. Section 608 of the US MSRA calling on the Secretary of Commerce, in consultation with the Secretary of State, and in cooperation with relevant regional fishery management councils and any relevant advisory committees, to take actions to improve the effectiveness of international fishery management organizations in conserving and managing stocks under their jurisdiction. EU IUU Regulation entered into force on 1 January 2010, was intended to regulate the highly complex multi-channel fisheries supply system of the European Community (EC) in an effort to improve global fisheries sustainability.

Implementation and Performance Analysis of Multi-GNSS Signal Collection System using Single USRP

  • Park, Kwi Woo;Choi, Yun Sub;Lee, Min Joon;Lee, Sang Jeong;Park, Chansik
    • Journal of Positioning, Navigation, and Timing
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    • v.5 no.1
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    • pp.11-20
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    • 2016
  • In this paper, a system that can collect GPS L1 C/A, GLONASS G1, and BDS B1I signals with single front-end receiver was implemented using a universal software radio peripheral (USRP) and its performance was verified. To acquire the global navigation satellite system signals, hardware was configured using USRP, antenna, external low-noise amplifier, and external oscillator. In addition, a value of optimum local oscillator frequency was selected to sample signals from three systems with L1-band with a low sampling rate as much as possible. The comparison result of C/N0 between the signal collection system using the proposed method and commercial receiver using double front-end showed that the proposed system had 0.7 ~ 0.8dB higher than that of commercial receiver for GPS L1 C/A signals and 1 ~ 2 dB lower than that of commercial receiver for GLONASS G1 and BDS B1I. Through the above results, it was verified that signals collected using the three systems with a single USRP had no significant error with that of commercial receiver. In the future, it is expected that the proposed system will be combined with software-defined radio (SDR) and advanced to a receiver that has a re-configuration channel.