• 제목/요약/키워드: media coverage

검색결과 243건 처리시간 0.025초

MIMO Spatial Multiplexing에서 안테나별 송신신호의 PAPR 감소 기법 (PAPR Reduction in MIMO Spatial Multiplexing for transmission antennas)

  • 배재휘;이광순;안충현
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2011년도 하계학술대회
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    • pp.466-469
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    • 2011
  • 최근 무선전송에서 SISO(single input singe output) 시스템의 전송률이 샤논 한계(Shannon limit)에 근접함에 따라, 이것을 극복하여 더 높은 데이터 전송률을 얻기 위해 MIMO(multiple input multiple output) 시스템에 대한 연구가 활발하게 이루어지고 있다. 현재 진행 중인 DVB-NGH 시스템 표준화에도 전송률 개선을 위해 MIMO SM(Spatial Multiplexing) 기술에 대해 고려하고 있으며, 방송 시스템 내 송수신 안테나들 간 상관(correlation)이 발생하는 경우에 성능 개선을 위해 Precoding과 MIMO SM을 결합한 $2{\times}2$ 구조의 MIMO SM 방법이 제안되었다. 이 방법은 두 개의 송신안테나에 모두 16QAM 신호가 전송되는 경우와 두 송신안테나에 각각 16QAM, QPSK 신호가 전송되는 경우를 포함하고 있다. 이때 고출력 증폭기(high power amplifier) 전단에서 두 송신 안테나에 서로 다른 변조가 적용되는 경우에 PAPR(peak-to-average power ratio)이 달라서 고출력 증폭기 출력단의 송신전력 차이로 인해 각 신호의 방송권역(coverage)이 같지 않은 문제가 발생한다. 본 논문은 이러한 문제를 극복하기 위해 $2{\times}2$ MIMO SM 방식에서 송신 안테나별로 신호의 변조방식이 서로 다른 경우에 송신신호의 PAPR을 같게 하여 증폭기 출력단에서 각 송신신호의 전력이 동일하게 할 수 있는 방법을 제안한다. 제안한 방법은 수신기의 복잡도를 증가시키지 않으면서 두 송신 신호의 방송권역을 동일하게 한다.

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코드 기반 기법을 이용한 디지털 회로의 스캔 테스트 데이터와 전력단축 (Reduction of Test Data and Power in Scan Testing for Digital Circuits using the Code-based Technique)

  • 허용민;신재흥
    • 전자공학회논문지 IE
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    • 제45권3호
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    • pp.5-12
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    • 2008
  • 디지털 논리회로의 테스트 데이터와 전력소비를 단축시킬 수 있는 효율적인 테스트 방법을 제안한다. 제안 하는 테스트 방법은 테스트장비내의 테스트 데이터 저장 공간을 줄이는 하이브리드 run-length 인코딩 벙법에 기초하고, 수정된 Bus-invert 코딩 방법과 스캔 셀 설계를 제안하여, 스캔 동작시의 개선된 전력 단축효과를 가져온다. ISCAS'89 벤치마크 회로의 실험결과 고장 검출율의 저하 없이 평균 전력은 96.7%, 피크전력은 84%의 단축을 보이며 테스트 데이터는 기존 방법보다 78.2%의 압축을 갖는다.

East Asian Trade Flows of Cultural Goods: A Gravity Model Approach

  • Yu, Shasha;Park, Eui Burm
    • 아태비즈니스연구
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    • 제2권1호
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    • pp.49-73
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    • 2011
  • With the market evaluation of economic globalization exchanges between different cultures, cultural trade has been developing at an accelerated speed, and also playing an important role in East Asian intra-regional trade. In this research the author used gravity trade model to explain the causal relationship between dependent variable trade flows and several independent variables applying with five categories cultural goods which classified in HS codes. Firstly for cultural heritage trade flow, the results indicated that economic masses of bilateral countries have no significant influences on it; GDP per capita of host country and adjacency factor with partner country have significant negative influences on it; Internet coverage ratio has improved cultural heritages exchanges in East Asian regions. Secondly for printed matter cultural goods trade flow, the distance factor has significant negative influence but common language has significant positive influence on it. Thirdly for recorded media cultural goods, only economic masses and GDP per capita of bilateral countries can improved their trade flows. Fourthly for visual arts cultural products trade flows, almost all variables we tested have significant influences on it. Fifthly for cinema photography cultural goods trade flow, the influenced factor are same with cultural heritage products except they have strong positive interaction relationship with economic masses and common language. At last, the paper figured out some important and potential sectors for cultural goods trade in East Asia and gave some suggestions to government and cultural goods product enterprises.

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An Efficient Power Control Algorithm for Satellite Communications Systems with ATC

  • Kim, Byung-Gi;Ryoo, Sang-Jin;Hwang, In-Tae
    • Journal of information and communication convergence engineering
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    • 제6권2호
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    • pp.129-133
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    • 2008
  • In this paper, modified power control algorithms are proposed for a satellite mobile communications system with ATC (ancillary terrestrial component). In order to increase system capacity and reduce the transmitting power of the user's equipment, we propose the modified power control scheme consisting of the modified closed-loop and open-loop power control. The modified CLPC (closed-loop power control) algorithm, combining the delay compensation algorithms and pilot diversity, is mainly applied to the ATC link in urban areas because it is more suitable to the short RTD (round-trip delay). In the case of rural areas where ATCs are not deployed or a signal is not received from ATCs, combining monitoring transmitting power equipment and OLPC (open-loop power control) algorithms using an efficient pilot diversity is mainly applied to the link between the user's equipment and the satellite. Two power control algorithms are applied equally to the boundary areas where two kinds of signals are received in order to ensure coverage continuity. The simulation results show that the modified power control scheme has good performance compared to conventional power control schemes in a GEO (geostationary earth orbit) satellite system with ATC.

Self-adaptive testing to determine sample size for flash memory solutions

  • Byun, Chul-Hoon;Jeon, Chang-Kyun;Lee, Taek;In, Hoh Peter
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권6호
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    • pp.2139-2151
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    • 2014
  • Embedded system testing, especially long-term reliability testing, of flash memory solutions such as embedded multi-media card, secure digital card and solid-state drive involves strategic decision making related to test sample size to achieve high test coverage. The test sample size is the number of flash memory devices used in a test. Earlier, there were physical limitations on the testing period and the number of test devices that could be used. Hence, decisions regarding the sample size depended on the experience of human testers owing to the absence of well-defined standards. Moreover, a lack of understanding of the importance of the sample size resulted in field defects due to unexpected user scenarios. In worst cases, users finally detected these defects after several years. In this paper, we propose that a large number of potential field defects can be detected if an adequately large test sample size is used to target weak features during long-term reliability testing of flash memory solutions. In general, a larger test sample size yields better results. However, owing to the limited availability of physical resources, there is a limit on the test sample size that can be used. In this paper, we address this problem by proposing a self-adaptive reliability testing scheme to decide the sample size for effective long-term reliability testing.

ATSC2.0 8-VSB/MH 융합형 3DTV 서비스 커버리지 측정 및 분석기 개발에 관한 연구 (Development of ATSC2.0 8-VSB/MH Hybrid 3DTV Service Coverage Measuring and Analyzing Equipment)

  • 김성훈;정경훈
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송∙미디어공학회 2016년도 추계학술대회
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    • pp.31-32
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    • 2016
  • 본 논문은 ATSC2.0 기반 8-VSB/MH 융합형 3DTV (A/104 Part 5 Service Compatible 3DTV using Main and Mobile Hybrid Delivery, A/104 part 5) 방식의 서비스 커버리지 및 음영지역을 예측할 수 있는 측정 및 분석시스템 개발에 대하여 기술 한다. ATSC2.0 기반 고정/이동 방송시스템은 8-VSB 로 전송되는 고정 TV 방송서비스(좌영상 전송)와 ATSC-MH 로 전송되는 in-band 모바일 방송서비스(우영상 전송)를 모두 수신하여 좌/우영상의 재생 및 동기화를 통해 융합형 3D 영상을 복원하게 된다. 따라서 융합형 3DTV 수신기는 고정 및 모바일 방송신호를 모두 수신하여야 융합형 3D 영상복원을 할 수 있으며, 방송사 입장에서 서비스 커버리지 측정을 하기위해서는 8-VSB 및 ATSC-MH 신호의 수신여부를 모두 측정하여야 한다. 본 논문에서는 이와 같은 RF 수신전계강도 파라미터 및 GPS 정보등을 실시간으로 모니터링하여, 시스템 사용자에가 융합형 3DTV 서비스 커버리지 측정 및 분석을 통해 서비스를 위한 RF 방송망 셀 구성 및 음영지역을 예측할 수 있는 ATSC2.0 융합형 3DTV 서비스 커버리지 분석기 구현에 대한 내용을 기술한다.

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CEO의 이미지가 브랜드 가치에 미치는 영향 (The Study on Identify components of CEO image Influence in Brand's value)

  • 김미경
    • 패션비즈니스
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    • 제12권1호
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    • pp.129-146
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    • 2008
  • The purpose of this study is to identify components of CEO image and to examine predictors to affect company's market value. To explore the social construction of the CEO Image depicted in the popular business newspaper, the Wall Street Journal and daily newspaper of Korea, was analyzed. Then, the reconstructed image of the CEO was compared with the firm's stock price change to see their relationship, if any. This paper focused on the case of Carly Fiorina as previous chief of Hewlett-Packard, who was the Fortune's ranking of the 50 most powerful women in business is presented. The period for the analysis was five years and eight months from her inauguration(July, 1999) to the release(February, 2005). The results, four predictors such as nature, management ability, leadership style, appearance character had statistically significant relationship with both company's market value and the image of CEO. In addition to revealed that media coverage of Carly Filoina was commensurate with the financial performance, particularly stock price change of the Hewlett-Packard. In general, the best image of the CEO is highly transcends to the image of the company as well. Therefore it is need to manage effectively components of CEO image to enhance brand image and its brand value, which are further expected to enhance company's market value.

Prioritizing the Preferences of Iranian Cancer Patients Regarding Acquisition of Health Information: Strategy for Patient Education

  • Zadeh, Jamileh Mahdi;Fard, Farahnaz Ghahreman;Madani, Raihaneh;Iravani, Homa;Kahouei, Mehdi
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권6호
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    • pp.2983-2988
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    • 2016
  • Recognizing cancer patients' preferences to obtain health information can help improve and reform the methods of communicating and providing proper services and consequently lead to effective patient education. The present cross-sectional study to prioritize the preferences of cancer patients regarding the acquisition of health informationwas conducted on cancer patients referred to hospitals affiliated to Semnan University of Medical Sciences in 2015. An anonymous self-administered questionnaire was developed. In the field of side effects of medications, 50 (46.7%) reported knowing about weight change, in the area of achieving relative health, 62(57.9%) announced awareness about diet, and 45 (42.1%) reported physical complications as a first regarding information needs. In the area of obtaining information, 50 (46.7%) tended to take their information through means outside of the hospital setting. These results can help with design of clinical information systems, as they inform the most relevant and useful coverage designed for cancer patients. Providing useful information through healthcare providers, the media and clinical information systems can act as a major source of social support for cancer patients.

WHO의 게임 이용 장애 질병 코드화 이후 언론의 게임 보도에 대한 내용 분석 (Content Analysis of News Coverage on Games after the Inclusion of Gaming Disorder in ICD-11)

  • 이숙정;육은희
    • 한국게임학회 논문지
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    • 제21권3호
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    • pp.91-106
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    • 2021
  • 본 연구는 게임 이용 장애 질병 코드화라는 맥락에서 게임에 대한 언론 보도의 특징을 살펴보고자 했다. 이를 위해 2019년 5월부터 2020년 8월까지 국내 5개의 종합일간지에 보도된 게임 기사 694건을 분석했다. 그 결과, 게임 산업에 대한 보도의 비율이 매우 높았으나 주로 산업 동향·기업사 경영 현황에 관한 보도였다. 정책 보도는 규제 정책이 압도적으로 많았고 특히 중독 관련 정책 보도가 주를 이뤘다. WHO의 질병 코드화를 찬성하는 의견만 다룬 보도는 매우 적었고 반대하는 의견만 다루는 보도와 찬반 의견을 모두 다루는 보도량이 비슷한 비율을 보였다. 반대 근거로는 산업계와 학계의 관점이 반영돼 있었다. 이용 효과 보도는 매우 낮은 비율을 보였으나 게임을 극단적인 범죄·일탈행위의 원인으로 보도하는 기존 관행을 그대로 따르고 있음을 알 수 있었다.

Roles of Malaysian Online Newspapers in the Construction of Public Opinion on Rare Earth Risks

  • Hasan, Nik Norma Nik;Dauda, Sharafa
    • Asian Journal for Public Opinion Research
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    • 제8권4호
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    • pp.432-452
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    • 2020
  • This study explored the representation of risks from the controversial Lynas rare earth refining as a risk event by five Malaysian online mainstream and alternative newspapers using qualitative content analysis. The aim is to uncover the role of the news media in the social amplification and attenuation of risks within the literature evidence as those roles are still uncertain. Content analysis is used to explore the online newspapers' roles guided by the Social Amplification of Risk Framework (SARF). The representations typified environmental, financial, health, occupational, property, radioactive, and technological risks and established connections between four risk types (environmental, financial, radioactive, and health risks). Radioactive risk was repeatedly associated with other risks, suggesting that the volume and information flow focused on radioactive risk as a key ingredient for amplification. This connection shows that the nature of the relationship between risks is multidimensional, contradicting the unidirectional type found in previous studies. Alternative online newspapers amplified and attenuated more risks, thus, providing more diverse coverage than mainstream sources. Consequently, this study provides evidence that risk representation from rare earth refining in a digital news environment is multidimensional and intensified or weakened in a multi-layered pattern. The stakeholders are engaged in a contestation by positioning their narratives to oppose or support their interests, which are amplified or attenuated by the online newspapers as social amplification stations.