• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.2A
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• pp.83-94
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• 2012

Various wireless communication devices or network such as WRAN and WLAN will coexist in the TVWS(TV White Space). Because of this coexistence, the wireless devices which use the TVWS have to avoid interfering to not only licensed TV receiver and wireless microphone but also homogeneous or heterogeneous TVBD(TV Band Device)s. In this paper, we propose two frequency sharing methods for the coexistence of WLAN and WRAN in terms of interference reduction and throughput enhancement in both homogeneous and heterogeneous networks. One is the WRAN spectrum etiquette to provide more wide bandwidth for WLAN users and the other is the WLAN frequency selection methods to improve the throughput performance. The simulation results have confirmed the throughput improvement of the proposed methods. Moreover, the proposed methods is also applicable to improve the throughput performance and reduce interference of similar systems working in a cognitive manner.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1149-1152
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• 2005

The frequency of inverters for driving multi-lamp backlights for LCD TV was synchronized to reduce noise from lamps and noise generated from PWM dimming.

• ETRI Journal
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• v.37 no.6
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• pp.1077-1086
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• 2015

This paper presents a general-purpose design scheme of a filter bank (FB)-based radio frequency (RF) transceiver that operates across the entire ultra-high frequency (UHF) TV band from 470 MHz to 698 MHz and complies with the TV white space (TVWS) regulatory requirements. To this end, an intermediate frequency (IF) band-pass filter (BPF) with a sharp skirt characteristic is considered as a solution for handling the incoming signals from a baseband modem. Specifically, an FB-based BPF structure with four ceramic resonator filters that effectively rejects unwanted signals is proposed to extract a desired signal in the TV band. Achievable data rates of a cognitive radio system (CRS) employing the proposed FB-based RF transceiver at the application layer are investigated in both wired and wireless environments. The service coverage of the CRS network is measured according to several modulation and coding schemes (MCSs) of the CRS. The results show that the coverage of a wireless network in a nearly open area can be extended by more than 9.3 km in the TVWS. Experimental results also confirm that the proposed FB-based RF transceiver is adequate for utilization in TVWS applications.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.1235-1238
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• 1998

In television stereo system, to produce the sound image for spatial impression is too difficult because of the narrow distence between two speakers. A method of widening the sound image using precedence effect was introduced but it didn't work effectively in low frequency band. In this paper, we propose a new method to produce an expanded sound image in full band of audio requency in band sound is expanded by phase shifting method and a higher frequency band sound is expanded by reflection. In simulation and experiment, the proposed system guarantees useful effect of sound image expansion in television stereo system.

• Journal of Advanced Navigation Technology
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• v.13 no.1
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• pp.54-61
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• 2009

In this paper, Switching to digital TV broadcasting and mobile operators license expiration period of the frequency, time and 700MHz, 800MHz and 900MHz frequency band plan for the redistribution is actively being discussed. Redistribution policy direction of these frequency 800MHz (bandwidth 10MHz) integrated command frequency for wireless networks(i.e TETRA) is expected to be considered a redistribution. These Integrated Wireless Network Infrastructure configurations at the time and data communication capabilities of the system unwilling TETRA Release 2 standard for the system is presented. This system is analyzed that Release 1 of the existing system takes up more than 6 times the increase of frequency bands. Therefore, integration of the frequency band assigned to the command of a wireless network with the introduction of advanced systems will not be able to do. In this paper to the digital TV transition, and the policy based on analysis of trends in the 700MHz band for the integration of wireless networks, provides policy direction for the allocation plan.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.2
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• pp.576-588
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• 2015

This study analyzed the influences of elementary students' usage of smartphone, computer and TV on academic attitude. Of the subjects residing in the U city to target of 10 elementary schools from the fourth grade to sixth grade, 865 students were sampled. This research made a frequency analysis and reliability analysis of the obtained date using SPSS 21.0 program were used. Research results are as follows. First, in the smartphone, computer and TV usage status of elementary school, smartphone, computer and TV were used the high frequency with which almost every commonly used, was found to be necessary to take advantage of the time to less than one hour a day, mostly alone, it has been found that a lot of online games, videos and SNS. Second, the use of smartphone, computer and TV were showed a significant effect on all sub-variables of open, self-concept, initiative, responsibility, learning enthusiasm, future orientation, creativity, self-assessment.

• Human Ecology Research
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• v.53 no.4
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• pp.341-350
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• 2015

This study explored the determinant variables influence of Chinese consumers' purchase intention towards products featured in Korean TV dramas vis-$\grave{a}$-vis product placement (PPL). We invited 248 Chinese adult consumers who had watched Korean TV dramas in last twelve months to participate in this survey. Data analyses were conducted by Cronbach's ${\alpha}$ reliability test, confirmatory factor analysis, t -test, analysis of variance and hierarchical multiple regression with SPSS ver. 21.0 and AMOS ver. 21.0. We chose PPL effects, product quality perceptions, and product trust as main independent variables. The empirical analysis results demonstrate that female (versus male) and frequency of (or longer time) watching dramas resulted in higher perceived consumer PPL effects, product quality, trust and purchase intention. The positive effects of the product quality and product trust on purchase intentions were confirmed. There are additional mediation effects of product quality perceptions and trust on the relationship between consumer demographic characteristics (gender), TV drama watching conditions (frequency and time) and purchase intention. This research can help Korean corporations produce effective advertising by indicating how PPL affects Chinese consumer consumption behavior. The results are useful for the Chinese government and consumer organizations to improve the domestic consumption environment by developing effective TV drama PPL policies.

• Journal of the Korea Society of Computer and Information
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• v.20 no.8
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• pp.7-13
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• 2015

Recently, there are serviced user customized advertisement of various type using smart device. Representative services are advertisement service using light of smart TV screen or audible sound of smart TV to transmit advertisement information. However, those services have to do a specific action of smart device user for advertisement information or need audible audio information of TV contents. To overcome those weakness, therefore, we propose an advertisement method using inaudible sound of speaker based on smart device. This method supports the transfer of advertising content to the smart device user with no additional action or TV audio signal required to access that content. The proposed method used two high frequencies among 18kHz ~ 22kHz of audible frequency range which smart TV can send out. And it generates those frequencies synthesized with audio of TV contents as trigger signal which can send advertisements to smart device. Next, smart device analysis the trigger signal and request advertisement contents related to the signal to server. After then, smart device can show the downloaded contents to user. Because the proposed method uses the high frequencies of sound signals via the inner speaker of the smart device, its main advantage is that it does not affect the audio signal of TV content. To evaluate the efficacy of the proposed method, we developed an application to implement it and subsequently carried out an advertisement transmission experiment. The success rate of the transmission experiment was approximately 97%. Based on this result, we believe the proposed method will be a useful technique in introducing a customized user advertising service.

• The Journal of the Korea Contents Association
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• v.21 no.9
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• pp.284-298
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• 2021

In addition to awareness building, TV media creates search behavior for the brand and the search result may link to a brand homepage and/or an e-commerce site. This study analyzed the impact of TV advertisements on a search volume at NAVER, a leading Korean search platform, in order to verify the impact of TV advertisements on brand-related search behavior. Results are as follows. TV advertisement exposure was significantly related to the amount of Korean search, English search, and total search. In addition, changes in TV advertising exposure also had a significant static influence on changes in search volume. The increase in the number of brand search was different by industries that carried out TV advertisements, and it was verified that the frequency of English searches increased faster than the frequency of Korean search as the exposure of TV advertisements increased. Therefore, domestic TV advertising volume has been verified to affect NAVER search volume, and the advertising industry and brand search language that conducted TV advertisements have been verified to be moderating variables. TV advertisements can be interpreted to cause brand search behavior in English even though it is not a native language for Koreans.

• Journal of Families and Better Life
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• v.21 no.2
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• pp.61-74
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• 2003

Recently, the number of consumers who buy various goods using the shopping channels on cable TV has increased. The objectives of this study are to examine the propensity of consumers to make an impulse purchase through cable TV, and to investigate the factors that influence consumers' impulse purchase. The following was found in this study: (1) The propensity of consumers to make impulse purchases on cable TV is somewhat low, Among sub-areas of impulse purchase, the propensity to make impulse purchase by suggestion is the highest. (2) Among the variables that affect consumers' impulse purchase on cable TV, the most influential variable is the psychological factor, followed by the frequency of shopping on cable TV, positive testimony from consumers who have used the product, and the amount of time spent in watching shopping channels on cable TV, in that order.