• Journal of Broadcast Engineering
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• v.13 no.3
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• pp.350-364
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• 2008

Single frequency network (SFN) design based on the Advanced Television Systems Committee (ATSC) specification, a terrestrial digital television (DTV) system, normally causes a interference problem, among signals from multiple transmitters or repeaters. To solve this, the ATSC recommended practice (RP) introduces a transmitter identification (TxID) signal embedded in a signal from each transmitter or repeater. A TxID signal analyzer is then used to detect the TxID signal, and following the analysis results, a SFN design can be adjusted. This paper discusses the generation and usages of Kasami sequence, is used the TxID signal. The configuration of the TxID signal analyzer to efficiently detect TxID signal is proposed and the results of theoretical performance analysis are provided. Moreover, computer simulation and laboratory test results are provided to evaluate the performance of TxID signal analyzer and the theoretical performance analysis.

• Smart Media Journal
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• v.4 no.1
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• pp.33-38
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• 2015

In this paper, we propose the methods not only to eliminate ELF(Extremely Low Frequency) EMI(Electro-Magnetic Interference) noice for extending recognition distance, but also to utilize the the PLN for detecting starting instance of a hand gesture using electric potential sensor. First, we measure strength of electric field generated in the smart devices such as TV and phone, and minimize EMI through efficient arrangement of the sensors. Meanwhile, we utilize the 60 Hz PLN to extract the starting point of hand gesture. Thereafter, we eliminate the PLN generated in the smart device and circuit of sensors. And then, we shield the sensors from an electric noise generated from devices. Finally, through analyzing the frequency components according to the gesture of target, we use the low pass filter and the Kalman filter for elimination of remaining electric noise. We analyze and evaluate the proposed ELF-band EMI eliminating method for non-contact remote sensing of the EPS(Electric Potential Sensor). Combined with a detecting technique of gesture starting point, the recognition distance for gestures has been proven to be extended to more than 3m, which is critical for real application.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.63-64
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• 2013

In this paper, a design method for a dual dipole antenna for an operation in the frequency band of 470-806 MHz for indoor digital TV (DTV) is studied. The proposed antenna is composed of two planar dipoles connected by parallel strip line, and the antenna is fed by a microstrip line. By employing different lengths of dipoles, a broadband characteristics is obtained, and the antenna is size-reduced by bending both ends of the longer dipole. The effects of each parameters on the antenna performance are examined by simulation, and the parameters are optimized for the DTV use. A prototype antenna with optimized parameters for the indoor DTV use is fabricated on an FR4 substrate and tested experimentally. The experimental results show that the frequency band for a VSWR < 2 ranges 458-864 MHz (61.4%, bandwidth 406 MHz, 1.89:1), and it corresponds fairly well with the simulated band 448-868 MHz (63.8%, bandwidth 420 MHz, 1.94:1).

• Journal of Nutrition and Health
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• v.36 no.5
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• pp.508-514
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• 2003

The purpose of this study was to analyze information about food and nutrition presented through the television broadcast media, with the aim of finding out the optimal communication method for supplying the general public with accurate information. To perform this study, a total of sixteen monitoring people were recruited and trained before and during the study. Five domestic TV channels were selected to be monitored, and the total monitoring period was six months. For maximum efficiency, the monitoring people were assigned to 8 teams. The results of the present study can be summarized as follows : First, the total reported cases of information about food and nutrition were 237, of which about 30% were judged appropriate and 70％ as inappropriate. Second, classifying each case by program type, information programs made up the highest portion at 82 cases (34.6%), cooking programs accounted for 76 cases (32.1%), news programs for 40 cases (16.9%), and entertainment programs for 7 cases (3.0%). The analysis showed that the greatest amount of incorrect information was found in dramas, followed by entertainment, information, cooking and news programs. Third, classifying each case by theme of contents monitored, meal preparation and cookery made up the highest portion at 86 cases (36.3%), foods accounted for 67 cases (28.3%), disease and diet-therapy for 40 cases (16.9%), eating habits for 31 cases (13.1%), and diet and fitness for 13 cases (5.5%). Incorrect information was conveyed most often on the themes of food habits, foods, disease and diet-therapy, cookery, and diet and fitness. Fourth, classifying each case by channel, Cable TV had the highest frequency at 72 cases (30.4%), MBC had 51 cases (21.5%), SBS had 43 cases (18.1%), KBS1 had 41 cases (17.3%) and KBS2 had 30 cases (12.7%). In conclusion, systematic monitoring should be continued to reduce the frequency of incorrect information being broadcast and to help ensure that accurate information is conveyed to the general public. Moreover, there should be a system of cooperation to provide information to help broadcast production teams establish a strategic program. Finally, it is essential to organize an advisory team by promoting links between the mass media and specialists in the field, and to develop an educational program on nutrition to help ensure the communication of accurate information on food and nutrition. (Korean J Nutrition 36(5): 508∼514, 2003)

• The Journal of the Korea Contents Association
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• v.21 no.1
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• pp.75-91
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• 2021

In this study, most of the previous researches on the analysis of apology are limited to comparative study of apology in different countries from the perspective of cross-cultural communication and analysis of apology in daily life. Therefore, by introducing pragmatics on apology strategy and cultural interpretation theories, this study tried to analyze apology and apology strategies in the seventh season of American TV series Desperate Housewives. Specifically speaking, based on Trosborg's classification of apology strategies, this study sorted out, classified and counted apology strategies in the seventh season of Desperate Housewives, and then 200 apology strategies were randomly selected and analyzed in detail. The statistical results showed that 'expression of apology' strategy was used at the highest frequency of 64.0%, followed by 'explanation or account' and 'minimizing the degree of offence'; 'Acknowledgement of responsibility', 'offer of repair' strategy, 'expressing concern for hearer' and 'promise of forbearance' were used relatively less frequently. The results can be interpreted by America's high individualism, low power distance and low-context culture having great influence on the frequency of American apology strategy. This study can increase understanding of apology and culture, reduce offence in communication with Americans, and make cross-cultural communication smooth, and meanwhile it is expected to enrich the research scope of TV drama art by analyzing language in TV drama art.

• Journal of Broadcast Engineering
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• v.16 no.6
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• pp.927-940
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• 2011

In this paper, we improve a time-domain channel estimation algorithm with multi-input multi-output (MIMO) systems for the next-generation digital television (DTV). The conventional algorithm use orthogonal codes for separating channels from the time-domain orthogonal frequency division multiplexing (OFDM) symbols. However. it has the disadvantage of reduced data-rate because of many pilots. The improved algorithm shows better performance than the conventional one even with reduced number of pilots. The improved algorithm is evaluated by computer simulations.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.12
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• pp.2505-2510
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• 2011

In this paper, we consider to obtain the criteria for maximal power of interfering transmitter according to distance between WiBro and WLAN in TVWS. We analyze this criteria as a parameter for co-use when hetero systems share the same frequency channels. In order to make an analysis of relationship between distance and power of two systems, we take into consideration on two cases. First, WiBro is an interfering transmitter and WLAN is a victim receiver. Second, WLAN is an interfering transmitter and WiBro is a victim receiver. Analyzed coexistence results under various co-use scenarios may be widely applied into the technique developed to get the coexisting condition for wireless devices using many communication protocols in same frequency.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.1 no.1
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• pp.23-31
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• 1976

When Television signal of VHF and UHF channel is retransmitted at the relay system with 6MHz Bandwidth including video and aural signals, the image is often affected with the unnatural changes of output amplitude frequency response within ttle region of dual sideband near to the carrier frequency. These phenomena are caused by the unnecessary lower sideband due to the spurious emission at the local oscillator, the nonlinear distortion in the linear amplifier, the intermoudulation distortion with the components of neighboring signal, the AM-PM conversion, and the envelope delay distortion. From the output characteristics, considering above results, the chief cause is caused by nonlinear response and has an effect on the bias states. Finally, it is confirmed that the effects on neighboring signal appear high in case of Down conversion than Up conversion and obtained the method for reducing the effects on the system.

• International Journal of Industrial Entomology and Biomaterials
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• v.11 no.1
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• pp.75-78
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• 2005

Inheritance of cocoon and shell weight characters in silkworm crosses between sex-limited at larva stage lines, including three (NIG$_{1}$ $\times$ TV$_{3/2}$ ,NIG$_{1}$ $\times$ TBV$_{2/24}$ and NIG$_{1}$ $\times$ B$_{2/6}$ ) from Japanese type and three (NIG$_{2}$ $\times$ B$_{2/6}$ ,TV$_{3/2}$ $\times$ NIG$_{1}$ and NIG$_{2}$ $\times$ TBV$_{2/24}$ ) from Chinese type was studied at Regional Centre for Scientific­Applied Service - Vratza during the period of 2000 ­2002. Inheritance of tested characters in F I was deter­mined through genetic parameters, additiveness (a), dominance (d) and their ratio (d/a). Degree and frequency of transgressions in F$_{2}$ were calculated also. Over dominance (d/a(>) 1) with bigger contribution of the parent with higher value was determined at inheritance tested characters. Transgressions obtained at cocoon and shell weight characters were positive and varied in wide limits. The productivity of parent's lines had defined the variability of genetic parameters for degree and frequency of transgressions. Combination of positive transgressions at cocoon and shell weight characters in F2 hybrid populations from sex-limited at larva stage allow us to select individuals with high productive potential for further use in selection programs.

• Journal of Broadcast Engineering
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• v.7 no.3
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• pp.271-276
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• 2002

It is very important to find errors in broadcasted streams because it can help us to find where errors occur. Broadcasted streams may have errors in the RF(radio frequency) or baseband domain. It is very important to fix these errors because it can help to stabilize set-top boxes, provide stable receiving, and give comfortable environments to watch TV. Since 2001, major terrestrial broadcasters in Korea started the DTV broadcasting in Kwan-Ak over Seoul area. In this paper, we provide some analysis on errors in MPEG-based TS streams, PSIP packets, and RF area which may occur in DTV systems and compare this result with that of USA.