• KSII Transactions on Internet and Information Systems (TIIS)
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• 제4권4호
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• pp.475-490
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• 2010

Cognitive Radio is an advanced enabling technology for the efficient utilization of vacant spectrum due to its ability to sense the spectrum environment. It is important to determine accurate spectrum utilization of the primary system in a cognitive radio environment. In order to define the spectrum utilization state, many CR systems use what is known as the quiet period (QP) method. However, even when using a QP, interference can occur. This causes reduced system throughput and contrary to the basic condition of cognitive radio. In order to reduce the interference time, a frequency-hopping algorithm is proposed here. Additionally, to complement the loss of throughput in the FH, a HMM-based channel prediction algorithm and a channel allocation algorithm is proposed. Simulations were conducted while varying several parameters. The findings show that the proposed algorithm outperforms conventional channel allocation algorithms.

• Journal of Nutrition and Health
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• 제35권1호
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• pp.115-123
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• 2002

This study was carried out to investigate the utilization status of internet dietary information by gender(boys: 363, girls: 366) in adolescent(middle & high school students). The results were summarized as follows. The internet using frequency of 6-7times per week had 45.0% of subjects and the using time of internet per a time was shown mainly'<2hours(68.5%)'. The main place for internet use was home(79.0%) and favorite search engine was 'Yahoo'(45.7%) and 'Daum'(19.3%). As main purpose using internet were mentioned 'social intercourse'(45.0%) and data search'(24.8%). The organization that offer to reliable internet information was educational institution'(49.4%). The problems in using information site were 'poor information'(26.4%), 'slow connection speed'(22.6%), and 'don't arouse interest'(18.8%). The search experience about dietary information had only 27.9% of subjects and search purpose was 'for homework'(33.3%) and 'for health'(32.0). The satisfaction degree of dietary information was not high. The connection motive to dietary information was mainly 'by site navigation casualty'(55.7%). Only 7.7% of subjects had experience of nutrition counseling using internet, and the motive of nutrition counseling was also 'by site navigation causally'(55.8%). The purpose of counseling was 'for diet'(41.5%) and 'for health problem'(30.2%), and the satisfaction degree of counseling result was very low. As the ask of improvement for counseling site were pointed out 'poor in answer content'(44.8%) and 'lazy answer'(31.0%). The subjects wanted to get the dietary information about 'growth in status'(41.4%), 'diet related skin beauty'(14.6%), the update period less 1 month, and the way of 'free board'(32.3%), 'game'(21.1%) and 'animation'(19.3%) as offer tool. The results of this study showed that although the internet using percent and frequency of subjects was high, they used dietary information very seldom and they are dissatisfied with internet nutritional information. Therefore, the information donor should consider which dietary information was needed and what is the optimal tool for adolescent.

• 한국생활과학회지
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• 제20권2호
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• pp.339-351
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• 2011

The purpose of this study was to inquire into how children's internet addiction is affected by home environments, computing environments, parental marital conflicts, parenting attitudes and parental monitoring and control as perceived by children. The study was conducted on 579 sixth graders at elementary schools located in Daejeon City. The data was analyzed by frequency, percentage, $X^2$, one way ANOVA, and scheffe analysis using the SPSS 18.0 version program. The results were as follows: first, out of 579 students, 5.0% were classified as at high-risk for addiction; 22.8% as at potential-risk; 72.2% as normal. Second, in the high-risk group, boys accounted for a higher percentage compared to girl students. Mothers' academic backgrounds and fathers' occupations affected the children's internet addiction. Third, the high-risk group tended to use the internet in internet cafes, to use it before going to elementary school, to use it for at least 4 hours once, and to use it to play games. Fourth, the high-risk group perceived parents marital conflicts as more frequent and more severer, as compared to other groups. Fifth, while the high-risk group perceived parenting attitudes as negative, the normal group perceived them as positive. Sixth, the potential-risk group and the normal group perceived parental monitoring and control as more frequent, as compared to the high-risk group.

• 대한가정학회지
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• 제40권12호
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• pp.85-108
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• 2002

The objectives of this study were to investigate the trend of the attitude and the behavior about consumer's internet premium advertisement and its application and the factors which influence on the attitude and the behavior about consumer's premium advertisement and its application; the demographic variables, internet communication-environment variables and variables in relation to consumer's premium advertisement application. For these purpose, the data collected two way: internet survey and questionnaire survey. The data used in this study included people who have looked an internet Premium Advertisement more than once during internet use. Major findings were as following: (1) The attitude of internet premium advertisement and its application could be described as the mean 34.16 md 24.61 separately(3.11 and 2.73 point on 5.00 points scale). The behavior of application about internet premium advertisement was measured as a behavior of application whether or not; application 18.7% and unapplication 81.3%. (2) The attitude of application about internet premium advertisement was significantly different according to age, joining frequency on internet, past experience of winning a premium, purchasing information search, interesting connection on the internet, the risk about the money loss and negative evaluation of other persons, the economical values of premiums, winning possibility, and preferable premiums. The behavior of application about internet premium advertisement, the behavior of application whether or not was significantly different according to sex, age, school career, a circuit speed, a period of using, joining frequency and a using place, past experience of winning a premium, purchasing information search, interesting connection on the internet, the risk about the negative evaluation of other persons, the economical values of premiums, winning possibility, and preferable premiums. (3) When looking at the influence of variables about the attitude of application about internet premium advertisement, the most influence variables was the past experience of winning a premium, and next was winning possibility, sex, the interest about the premiums which made the consumer want to apply, the economical values of premiums, the purpose of purchase information search and the using time. The explanation of those variables were 22.6%. As the result of the Logistic analysis, it was found that the frequency of the internet connection, the past experience of winning premiums, the risk about the outflow of credit information, interesting premiums, and premium advertisement were the most important variables to affect the possibility of the behavior of application about internet premium advertisement critically.

• 인터넷정보학회논문지
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• 제19권5호
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• pp.115-122
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• 2018

This study examined the relationship between SNS use and individual psychological well-being on Instagram. In particular, this study sorted three types of perceived social support-informational, companionship, and self-esteem-to investigate how they influenced individual life satisfaction and loneliness. Results from a survey of 174 college students showed that: (1) frequency of Instagram use was a significant predictor of all three types of perceived social support; (2) status updates had positive effects on perceived self-esteem support, while posting photos was a significant predictor of perceived companionship support; (3) browsing others' profiles was a significant negative predictor of perceived self-esteem support and finally (4) perceived companionship social support had a positive effect on life satisfaction, whereas self-esteem social support had a negative effect on loneliness. These findings imply that Instagram users obtain specific types of social support depending on which activities they engage in and that different types of social support have different effects on well-being.

• 가정과삶의질연구
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• 제20권4호
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• pp.135-148
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• 2002

The main purpose of this research was to explore the factors that encourage people to use the cyber counseling in resolving difficulties in their lives. Another purpose of this research was to investigate whether cyber counseling really helps people feel better. For this study, a structured survey questionnaire was distributed both on- and off-line, and 429 respondents returned completed survey forms. The major statistical methods used for data analysis were frequency, factor analysis, 1-test and ANOVA. The results of this study revealed that variables such as gender, age, occupation, internet skills, time of internet use, personality, and the awareness of cyber counseling made a difference in people's use of cyber counseling whenever they felt they needed it. However, cyber counseling seemed to fail to increase feelings of well being in people's lives. The implications of these findings are discussed in this article.

• 정보교육학회논문지
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• 제10권1호
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• pp.47-57
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• 2006

10대 학생들의 인터넷 사용이 증가하고, 인터넷이 그들의 일상생활에서 중요한 영역을 차지하게 됨에 따라서 인터넷 중독에 대한 우려의 목소리가 커지고 있다. 본 연구는 학생들을 대상으로 사용할 수 있도록 국내에서 개발된 '인터넷 중독 자가진단 척도'를 사용하여 10대 학생들의 인터넷 중독 실태를 분석하고, 초등학생의 중독 수준과 중 고등학생의 중독 수준을 비교하였다. 또한 인터넷 중독에 영향을 주는 요인에 대해서 알아보고자 '인구학적 배경', '인터넷 사용 경험', '가족 관련 특성', '사회적 활동' 등과 같은 4가지 영역에서 18가지의 요인들을 선정하여, 각 요인별로 학생들의 인터넷 중독 수준에 따라서 유의미한 차이가 있는지를 분석하였다. 전국 규모로 1,155명의 초등학생과 1,882명의 중 고등학생들을 대상으로 2005년 7월에 인터넷 중독의 실태에 대한 설문조사를 실시한 결과, 초등학생의 5.0%에 해당하는 학생들이 고위험 사용자군으로 그리고 19.7%의 학생들이 잠재적위험 사용자군으로 분류되었다. 또한 초등학생의 중독률이 중 고등학생의 중독률보다 통계적으로 유의미하게 더 높은 것으로 나타났다. 한편 초등학생의 경우에 성, 하루 인터넷 사용 시간, 사용 목적, 부모 관계 만족도, 부모의 인터넷 사용 간섭, 가족 대화 시간, 학교 생활만족도 등에 대해 중독 수준 집단 간에 유의미한 차이가 나타나 주요 영향 요인으로 발견되었다.

• 한국도서관정보학회지
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• 제39권1호
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• pp.33-50
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• 2008

본 연구의 목적은 의사들이 환자 치료와 학술적인 연구를 하기 위해 요구하는 정보를 효율적으로 제공하는데 그 목적이 있다. 2007년 12월 3일부터 12월 21일까지 3주 동안 의사 177명을 대상으로 조사하였으며 이용자들의 정보요구와 이용행위로 정보수집방법과 정보원, 그리고 도서관 이용정도와 만족도를 평가하였다. 의사들은 최근의 연구동향을 알고자 할 때와 환자 치료를 위해 정보를 가장 많이 필요로 하는 것으로 나타났다. 의사들이 그들의 정보요구를 충족시키기 위해 선호하는 정보수집방법은 인터넷 검색으로 그 이유는 정보접근의 편이성과 정확성, 최신성인 것으로 나타났다. 의사들은 정보가 필요할 때 주로 도서관을 이용하여 필요한 정보를 얻는 경향이 있으나 대체적으로 보아 도서관 이용빈도수는 매우 적은 것으로 나타났다.

• 한국생활과학회지
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• 제11권4호
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• pp.335-346
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• 2002

The purpose of this study was to investigate how much adolescents use the internet and how much they are addicted to the internet, and to examine the relative effect of the personal and family related variables on the internet addiction. Data was collected through a questionnaire survey given to 420 students of middle school in Kwangju province. The data were analyzed by frequency, percentage, stepwise multi-regression analysis, Cronbach's $\alpha$, and Pearson's correlations coefficient. The major findings obtained from this study were as follows: 1. The proportion of internet addiction of adolescents was 9.1%. 2. Parent's control, positive family emotion and self-efficacy were proved to be the most significant variables. The internet addiction increased as the score of parent's control got higher, and the scores of the positive family emotion and the self-efficacy lower. 3. Because the positive family emotion was found to be a very important factor in determining internet addiction, this research proposes that the further family life education program should be developed to facilitate the normal family functioning in relations with preventing internet addiction.

• 대한가정학회지
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• 제44권5호
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• pp.79-87
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• 2006

The purpose of this study is to analyze whether service quality and perceived risk have an effect on purchase intention and satisfaction of the fashion merchandise in internet shopping malls. To this end, a survey was conducted from June 20 to July 30 in 2005, among married women aged in their 20s and 30s, on their purchase experience of fashion merchandise from internet shopping malls. The survey was conducted over the internet with 306 subjects. The statistical analysis methods were frequency analysis, reliability analysis, factor analysis, and multiple regression analysis. First, the service quality factors were determined to be reliability, responsibility, ease of transaction, order convenience, and site characteristics. Perceived risk factors were determined to be merchandise risk, information exposure risk, social psychological risk, and function risk. Second, service quality factors of responsibility, ease of transaction, order convenience, site characteristics and perceived risk factor of social psychological risk had an effect on internet purchase intention of the fashion merchandise. Greater site use convenience, lower price, simpler ordering, and lower social psychological risk were all positively correlated with higher internet purchase intention of fashion merchandise. Third, nice quality factors and social psychological risk had an effect on satisfaction degree in internet shopping.