• Title/Summary/Keyword: broadcasting system

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A PAPR Reduction Technique by the Partial Transmit Reduction Sequences (부분 전송 감소열에 의한 첨두대 평균 전력비 저감 기법)

  • Han Tae-Young;Yoo Young-Dae;Choi Jung-Hun;Kwon Young-Soo;Kim Nam
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.17 no.6 s.109
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    • pp.562-573
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    • 2006
  • It is required to reduce the peak-to-average power ratio(PAPR) in an orthogonal frequency division multiplexing system or a multicarrier system. And it is needed to eliminate the transmission of the side information in the Partial Transmit Sequences. So, in this paper, a new technique is proposed, where the subcarriers used for the multiple signal representation are only utilized for the reduction of PAPR to eliminate the burden of transmitting the side information. That is, it is proposed by taking the modified minimization criteria of partial transmit sequences scheme instead of using the convex optimization or the fast algorithm of tone reservation(TR) technique As the result of simulation, the PAPR reduction capability of the proposed method is improved by 3.2 dB dB, 3.4 dB, 3.6 dB with M=2, 4, 8(M is the number of partition in the so-called partial transmit reduction sequences(PTRS)), when the iteration number of fast algorithm of TR is 10 and the data rate loss is 5 %. But it is degraded in the capability of PAPR reduction by 3.4 dB, 3.1 dB, 2.2 dB, comparing to the TR when the data rate loss is 20 %. Therefore, the proposed method is outperformed the TR technique with respect to the complexity and PAPR reduction capability when M=2.

Korean Public Relations Trend and Social Acceptance in 1960s (1960년대 한국의 PR 상황 및 사회적 수용에 대한 연구)

  • Chae, Myung-Jin;Seon, Hye-Jin
    • Korean journal of communication and information
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    • v.35
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    • pp.292-328
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    • 2006
  • This study examined Korean Public Relations trend and social acceptance in 1960s. It centers on the acceptance conditions of PR concept, corporate PR and governmental PR. It analyzed PR recognition and practical activities of the general corporations, financial institutions and public corporations in dealing with corporate PR. It also analyzed Korean governmental PR through examining the structure of governmental PR system, PR activities in rural communities and the police. In those days, PR concept had been misused to no small degree and not been accepted correctly that the necessity to let people know PR in its proper meaning was raised. Laying emphasis upon the technical side, corporate PR activities had centered on publicity. Especially, at that time, the banks, the insurance companies and the public corporations had perceived the importance of PR and implemented a set of PR activities. It can be said that a special feature in government PR in 1960s lies in the expansion of the public information system and reinforcement of PR policies. Also, PR in rural communities had been doing to give information relating to agriculture technique and to improve the living conditions of the farm area. The importance of PR in police had been on the side of promoting relations with people and improving treatment of the people by policeman.

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An Analysis of Optimal Sequences for the Detection of Wake-up Signal in Disaster-preventing Broadcast (재난방송용 대기모드 해제신호 검출을 위한 최적 부호 성능 분석)

  • Park, Hae Yong;Jo, Bonggyun;Kim, Heung Mook;Han, Dong Seog
    • Journal of Broadcast Engineering
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    • v.19 no.4
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    • pp.491-501
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    • 2014
  • Recently, the need for disaster-preventing broadcast has increased gradually to cope with natural disaster like earthquake and tsunami causing enormous losses of both life and property. In disaster-preventing broadcast system, the wake-up signal is used to alert user terminal and switch the current state of channel to the emergency channel, which is for the fast and efficient delivery of emergency information. In this paper, we propose the detection method of wake-up signal for disaster-preventing broadcast systems. The wake-up signals for disaster-preventing broadcast should have a good auto-correlation property in low power and narrow-band conditions that does not affect the existing digital television (DTV) system. The suitability of the m-sequence and complementary code (CC) is analyzed for wake-up signals according to signal to noise ratio. A wake-up signal is proposed by combining the direct sequence spread spectrum (DSSS) technique and pseudo noise (PN) sequences such as Barker and Walsh-Hadamard codes. By using the proposed method, a higher detecting performance can be achieved by the spreading gain compared to the single long m-sequence and the Golay code.

Effects of Consumer Awareness of Organic Agricultural Products on Repurchase Intention (유기농산물 소비자인식이 재구매의사에 미치는 영향)

  • Seo, Yong-Sil;Seo, Yoon-Jeong;Lee, Jin-Hong;Lee, Byung-Oh
    • Journal of Distribution Science
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    • v.13 no.11
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    • pp.59-67
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    • 2015
  • Purpose - The number of consumers adopting a lifestyle of health and sustainability has recently increased with the rise of trends in healthy living. The size of the organic agricultural product market has also increased given that these consumers prefer consuming environmentally friendly products that promote family health. However, awareness of organic agricultural products remains insufficient because of the characteristics of the Korean organic agriculture system, which only focuses on food safety inspection. The object of this research is to suggest a policy approach to increase understanding and to expand the purchasing of organic agricultural products by analyzing the influence of customer recognition of such products on their willingness to repurchase. Research design, data, and methodology - This study used binomial logistic regression analysis with the aim of explaining the effects of consumers' socio-demographic characteristics, their awareness of the equivalence arrangement for organic food and of the abolishment of low-pesticide agricultural product certification, and their viewing of negative broadcasts about organic agricultural products on their repurchase intention of such products. A questionnaire survey was conducted with 655 respondents who were in their 20s, lived either in Seoul or in its metropolitan area, and had purchased organic agricultural products. Result - From the results of the analysis, the majority of the respondents recognized organic agricultural products, but they found their prices to be expensive. The majority of the respondents were also aware of the certification system and the reliability of organic agricultural products. However, the results indicate that efforts need to be made to recover consumer trust as many respondents stated that their trust levels in these products were low. In general, those purchasing organic agricultural products were satisfied, but those answering "very satisfied" were not in the majority. Binomial logistic regression analysis results revealed that repurchase intention decreased as consumers viewed a greater number of negative broadcasts about these products. On the other hand, repurchase intention increased as they became more aware of the abolishment of low-pesticide certification. Repurchase intention also increased as income increased, as the number of family members decreased, and when a consumer was a member of a consumer organization. In addition, the older the consumers were who watched the TV programs, the smaller the number of family members that were aware of the abolishment of low-pesticide agricultural product certification and, the higher the income of the consumers aware of organic equivalence arrangement, the greater their repurchase intention. Conclusion - External stimuli, such as negative TV programs on organic agricultural products and the abolishment of the low-pesticide agricultural product certification, relevant social issues and systems, influence consumer repurchase intention. To that end, positive environmental and ecological broadcasting about organic agricultural products would contribute to an increase in purchasing. Additionally, this could be used for promotion and marketing plans as the results indicate that trust in organic agricultural products would cause a positive repurchasing effect.

Analysis of Diversion Rate using Expressway Traffic Data(FTMS, TCS): Focusing on Maesong~Balan IC at Seohaean Expressway (고속도로 교통데이터(FTMS, TCS)를 이용한 경로전환율 분석: 서해안고속도로 매송~발안 구간을 중심으로)

  • Ko, Han-Geom;Choi, Yoon-Hyuk;Oh, Young-Tae;Choi, Kee-Choo
    • Journal of Korean Society of Transportation
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    • v.30 no.3
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    • pp.31-41
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    • 2012
  • Due to growing interests in the distribution of traffic volume through information dissemination such as VMS and traffic broadcasting system, the research on the driver's reaction and effect of the traffic report has continued. In this study, we propose a methodology, which estimates the traffic volume of diversion and the consequential diversion rate using FTMS data and TCS data, and the estimation is based on the analysis of the national highway and IC, in which real-time FTMS and TCS data are established. We also calculate the diversion rate of actual targeted sections and analyze the changes in time and spatial diversion rate. In this study, we define a deviation (considering a deviation due to dynamic properties of traffic conditions) found when the outflow traffic volume is temporarily higher than the average outflow traffic volume on a relevant time slot after providing traffic information. The diverting volume is considered to be caused by the traffic information, and the study determines the ratio of traffic volume on highways to that of route diversion as the diversion rate. The analysis on changes in the diversion rate in accordance with the time flow, the initial change in the diversion rate on upstream IC that first acquires the report on the traffic congestion is significant. After that, the change in the diversion rate on upstream IC affects the route diversion on downstream IC with spatial and time flow, and this again leads the change in upstream IC. Thereby, we confirmed that there is a feedback-control circulation system in the route diversion.

A New Upper Layer Decoding Algorithm for a Hybrid Satellite and Terrestrial Delivery System (혼합된 위성 및 지상 전송 시스템에서 새로운 상위 계층 복호 알고리즘)

  • Kim, Min-Hyuk;Park, Tae-Doo;Kim, Nam-Soo;Kim, Chul-Seung;Jung, Ji-Won;Chun, Seung-Young
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.20 no.9
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    • pp.835-842
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    • 2009
  • DVB-SSP is a new broadcasting system for hybrid satellite communications, which supports mobile handheld systems and fixed terrestrial systems. However, a critical factor must be considered in upper layer decoding which including erasure Reed-Solomon error correction combined with cyclic redundancy check. If there is only one bit error in an IP packet, the entire IP packet is considered as unreliable bytes, even if it contains correct bytes. IF, for example, there is one real byte error, in an If packet of 512 bytes, 511 correct bytes are erased from the frame. Therefore, this paper proposed two kinds of upper layer decoding methods; LLR-based decoding and hybrid decoding. By means of simulation we show that the performance of the proposed decoding algorithm is superior to that of the conventional one.

A Concept of Media-Environment and Its Policy Implications: Focusing on the Policy Discussions Concerning the Public Interest Idea (미디어 환경개념의 정책적 함의: 공익성 관련 논의를 중심으로)

  • Kim, Pyung-Ho
    • Korean journal of communication and information
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    • v.43
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    • pp.152-172
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    • 2008
  • The convergence of media poses serious challenges to technologies, industries and policy makers. At the core of the challenges lies a socially and culturally problematic condition of 'media unlimited.' Under the circumstances, the idea of public interest of the media seems to lose its intervening leverage as it flounders in countering 'the media torrent' rushing from the exponential growth of ICTs that overwhelms contemporary life and society. It is an urgent task for the critical community to blaze fresh new thoughts about the idea to intervene in the current age of media excess. Beyond the conventional content-conduit-centered perspective on the media, this study suggests a media-environment concept based on media ecology as an engaging leverage to replenish the public interest idea. The environmental approach to the media means literally to conceptualize the media as environment--a cultural eco-system. This study explores the potential of ecological approach in enriching the conceptual terrain of policy discussions and policy-making processes concerning the public interest idea that hopefully enlightens all the media actors concerned.

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A Study on Enhancing VMS Services by FM Car Radio (차량 내 FM라디오를 이용한 VMS서비스 개선 연구)

  • Park, Bum-Jin;Moon, Byeong-Sup
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.9 no.6
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    • pp.22-32
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    • 2010
  • Increasingly advanced Information Technology (IT) has changed the operator so as to create more diversified and advanced traffic information demand. To deal with the changing demand in private sector, a concept of on-demand traffic information has been rapidly introduced. However VMS, a product of the first generation of ITS, which was designed to provide the unspecified individuals during driving the car with the basic level of traffic information by the public failed to actively change itself in such a changing pattern. This study was intended to describe the VMS system (tentatively, FM-VMS) which was further developed to accommodate the needs favoring the sophisticated PDA with the public role of providing the unspecified individuals with the equal information. FM-VMS introduced in this study is the device designed to transmit the voice and message to the drivers through the radio information device mounted on a car. A core technology is, unlike FM-DARC and RDS, the Water Making technology which directly inserts the digital signal into FM frequency in use. It's been currently used for broadcasting and security purpose. A detection rate as a result of testing FM-VMS system using Water Making technology was 90% or more in voice and message within 20m from test VMS. When a public-developed VMS information could be transmitted using FM frequency to the relatively vulnerable users (vulnerable to traffic information) in voice on a real-time basis to provide the regional traffic information, and furthermore, VMS message could be received through radio liquid using FM frequency only, it would obviously bring about the innovation in ITS as well as pave the way for creating the new added value down the road.

Design of Digitalized SECAM Video Encoder with Modified Anti-cloche filter and SECAM Video Decoder with BPF and Error-free Square Root (개선된 Anti-cloche Filter와 BPF 그리고 오차가 없는 제곱근기를 사용한 SECAM Encoder와 Decoder의 설계)

  • Ha, Joo-Young;Kim, Joo-Hyun;Kang, Bong-Soon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.3
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    • pp.511-516
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    • 2006
  • In this raper, we propose the Sequentiel Couleur Avec Memoire or Sequential Color with Memory (SECAM) video encoder system using modified anti-cloche filters and the SECAM video decoder system using a band pass filter (BPF) and an error-free square root. The SECAM encoder requires an anti-cloche filter recommended by International Telecommunication Union-Recommendation (ITU-R) Broadcasting service Television (BT) 470. However, the design of the anti-cloche filter is difficult because the frequency response of the anti-cloche filter is very sharp around rejection-frequency area. So, we convert the filter into a hish pass filter (HPF) by shifting the rejection frequency of 4.286MHz to 0Hz frequency. The design of HPF becomes very easy, compared to that of the anti-cloche filter. The proposed decoder also uses an error-free square root, two differentiators and trigonometric functions to extract color-component information of Db and Dr accurately from frequency modulation (FM) signals in SECAM systems. Also, the BPF in decoder it used for removing color noise in chrominance and dividing CVBS into chrominance and luminance. The proposed systems are experimentally demonstrated with Altera FPGA APEX20KE EP20K1000EBC652-3 device and TV sets.

Multimedia Network Teaching System based on SMIL (SMIL을 기반으로 한 멀티미디어 네트워크 교육시스템)

  • Yu, Lei;Cao, Ke-Rang;Bang, Jin-Suk;Cho, Tae-Beom;Jung, Hoe-Kyung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.10a
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    • pp.524-527
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    • 2008
  • Recently, digital and the Internet are widespread out of the world, and multimedia processing technology and the development of information and communication technology in education using the Internet as the demand is rapidly increasing. Also, we tan easily use informations with less restrictions of time and space. however, several kinds of audio, media to integrate multimedia data, such as the proliferation of demands for representation. Therefore, in 1998, W3C presented an international standard, SMIL in order to solve multimedia object representation and synchronization problems. By using SMIL, various multimedia elements can be integrated as a multimedia document with proper view in a spate and time. Using this SMIL document, we can create new internet radio broadcasting service that delivers not noly audio data but also various text, image and video. In this paper, with the system, teachers can easily create multimedia courseware and living broadcast their torture on network, students can receive audio-video information of the teacher, screen displays of the teachers computer. Moreover students can communicate with teacher simultaneously by text editor windows. Students can also order courseware after class.

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