• 응용통계연구
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• 제29권5호
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• pp.907-920
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• 2016

본 논문의 목표는 분위수 자기회귀모형을 활용하여 시계열 자료에서 특이치를 발견하는 알고리즘을 제안하고, 기존의 방법들과 그 성능을 비교하여 실제 주가 조작 사례에 적용해 보는 것이다. 지금까지의 특이치 발견 연구는 대부분 일반적인 데이터 형태에서만 있어왔기 때문에 시계열 데이터에서의 연구는 미미한 편이다. 또한 모수적인 방법에만 제한되었는데, 모수적 모형은 복잡할 뿐만 아니라 소요되는 분석 시간도 길기 때문에 편리하지 않다. 따라서 본 연구에서는 분위수 자기회귀모형을 활용한 특이치 발견 알고리즘을 새롭게 제시하고, 다양한 경우의 모의실험을 통해 기존 알고리즘과 비교하도록 한다. 특히 시계열 자료에서의 특이치 발견은 주가 조작을 적발하는 데에 유용하게 활용될 수 있다. 시간에 따라 관측되던 주가가 갑자기 그 동안의 흐름에서 벗어나 특이치로 발견되었다면 혹시 인위적인 개입으로 조작된 것은 아닌지 의심해 볼 수 있기 때문이다. 따라서 실제 주가 조작 사례에 적용해 봄으로써 얼마나 빠른 시일 내에 주가 조작을 적발해 낼 수 있는지 살펴보았다.

• 자원ㆍ환경경제연구
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• 제24권1호
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• pp.225-249
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• 2015

우리나라 전력시장에서도 보다 선진화된 요금체계가 도입되어야 한다는 관점에서 가정부문에서의 선택적 전력요금제 도입이 논의되고 있다. 본 연구에서는 고정요금제, 실시간 요금제(RTP), 계시별 요금제(TOU)를 도입하였을 때의 효과를 분석하기 위해 행위자기반모형을 구축하였다. 시간대별 전력소비 유형이 다른 행위자를 설정하였으며, 전력수요와 전력가격을 연동시키기 위해 발전부문도 모형에 도입하였다. 분석 결과, 소비자 유형이 피크부하 때 덜 사용하는 경우에는 실시간 요금제인 RTP나 TOU를 택했을 때의 비용절감 효과가 컸으며, 특히 스마트 계량기 등을 이용하여 전력사용 시간을 최적화할 수 있는 경우에는 그 편익이 더욱 증가한 것으로 나타나 향후 스마트 전력소비를 위한 인프라 구축이 필요함을 알 수 있다.

• 자원ㆍ환경경제연구
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• 제20권2호
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• pp.229-254
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• 2011

본 논문은 LMDI(Log Mean Divisia Index) 방법론을 이용하여 국내 제조업의 온실가스 배출에 대한 요인분해분석을 하였다. 국내 제조업의 온실가스 배출에 대한 요인분해는 크게 생산효과, 구조효과, 집약도효과, 에너지믹스효과, 배출계수효과 등 다섯 가지 요인으로 분해하였다. 1991년~2007년까지 국내 제조업의 온실가스 배출변화 요인을 분석한 결과를 보면 국내 제조업의 온실가스 배출은 대부분 생산효과에 의해서 증가하였다. 구조효과와 집약도는 온실가스 배출을 줄이는 역할을 하였으며, 구조효과보다는 집약도효과가 더 많이 온실가스 배출을 감소시키는 방향으로 작용하였다. 그리고 에너지믹스효과와 배출계수효과는 다른 효과들에 비해서 그 비중이 작지만 온실가스 배출 증감에 영향을 미치고 있다. 에너지믹스효과는 온실가스 배출 증가 요인으로 배출계수효과는 감소요인으로 작용하였다. 한편 시계열로 에너지 소비를 요인분해 해 본 결과 1998년 IMF 체제를 전후로 온실가스 패턴에 변화가 일어났다. IMF 체제 이후로 구조효과와 집약도효과에 의한 온실가스 감축이 IMF 체제 이전보다 더욱 두드러진 것이 특징이다. 2001년 이후 진행된 신고유가 시대를 맞이해서는 구조효과와 집약도효과가 더욱 촉진되었다.

• 대한지역사회영양학회지
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• 제12권5호
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• pp.534-544
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• 2007

This study was carried out to investigate the fast food consumption patterns classified by age in Busan. The survey was conducted from October 15 to November 15, 2006 by questionnaires and data analyzed by SPSS program. The results are summarized as follows: Forty one point five percent of the elementary group, 40.5% of the high school group, 24.1% of the 30's, 35.0% of the 40's and 18.1% of the 50's took fast foods over once a week. Seventy two point five percent of the elementary group, 61.5% of the high school group, 16.8% of the 30's group, 10.0% of the 40's, and 14.6% of the 50's preferred fast foods. There was a significant difference in the basis for selecting menus among the groups. The most important basis for selecting menus was 'price' in the elementary group and the high school group, but was 'preference' in the adult groups. As their age increased, they spend more money for fast food. Forty six percent of the elementary group and 49.5% of the high school group, 32.1% of the 30's, 36.5% of the 40's, 34.7% of the 50's thought that fast food can substitute for a meal. The age affected significantly the substitutability for the meal of the fast food (p < 0.001). In the high school group, the ratio of skipping breakfast is higher than in the other age groups. Dietary attitude has direct effects on the preference of the fast foods. Nutrition knowledge, degree of unbalanced diet and obesity rate have direct and indirect effects which were mediated by dietary attitude. Nutrition knowledge showed the greatest total causal effect in relation to the preference of the fast foods. Therefore, nutrition education for the subjects is needed to encourage them to choose more nutritious food and have healthier dietary pattern.

• 한국의류학회지
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• 제30권1호
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• pp.20-30
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• 2006

The purposes of this study were to investigate demographic profiles between the consumer group under high time pressure(HTP) and the group under low time pressure(LTP) during the shopping, to examine the level of association between the fashion information sources and time pressure variable, to determine the difference in clothing benefits sought between HTP and LTP, and to determine the difference in purchase criteria. We distributed questionnaires to 600 women aged in 20-65. The reliable 562 questionnaires were used for a statistical analysis. Data analyses were conducted with SPSS program on t-test, cluster analysis, factor analysis, and Chi square test. We obtained the following results: There was a significant association between demographic variables such as age, occupation, education, residence area, & family cycle and time pressure variable. Fashion information sources were classified into 4 factors. HTP searched information on fashion products using more various sources than LTP did. There was also a significant difference between HTP and LTP in clothing benefit sought. Four clothing benefit factors such as trendy/social position, economic value, protection/comfort, and makeup of body shape were sought more by HTP than by LTP. In addition, HTP considered significantly more purchase criteria such as color/pattern, comfort, quality, suitability, material, sewing finishing, coordination, price, brand, easy care, and country of origin than LTP.

• 한국식품영양학회지
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• 제25권2호
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• pp.299-307
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• 2012

In this study, Kimchi usage was examined by nationwide consumers. 1,000 consumers between 20~60 years olds from 15 cities/province based on an administrative district participated in this questionnaire, which were one-on one interviews from September 23th to October 14th, 2009. 76.1% of the customers prepared Kimchi by them self, 26.9% customers received Kimchi from relatives and, 13.1% purchase Kimchi from the market. In addition, the rate of preparing Kimchi by themselves increased with age(p<0.05). 4~6 cabbage heads(34.5%) was the most preferred quantity for preparing Kimchi at a time, which was followed by more than 10 heads(25.2%) and 2~3 heads(22.9%). Chinese cabbage Kimchi was the most preferred type for purchase. 49.1% of customers purchased Kimchi at the supermarket and warehouse market and the origin of the ingredients, taste and-, price of Kimchi were considered important factors. The satisfactory scores of selling Kimchi were variety 3.60, taste 3.11, freshness of main ingredient 3.10, hygiene 2.86, -appropriate salt usage 2.99 and-, the origin of ingredients 2.94. There were significant difference between gender in taste and hygiene of selling Kimchi (p<0.05). In conclusion, to provide more appropriate Kimchi based on changes in Kimchi usage and consumption patterns at home and in the community, new types of Kimchi should be developed.

• 한국전자파학회논문지
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• 제25권1호
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• pp.39-46
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• 2014

본 논문에서는 On-Board Broadband 특성을 갖는 2.4 GHz Inverted-L 안테나를 제안하였다. 안테나는 시스템 보드에 Inverted-L 안테나를 설계하였으며, 공통 모드와 차동 모드를 형성하도록 스터브를 설계하여 안테나의 리액턴스를 조정하여 대역폭을 개선하였다. 시스템 크기는 $80mm{\times}60mm$이고, 안테나 영역은 $30mm{\times}60mm$로 제한하였으며, 기판은 두께가 0.8 mm이고, 유전율이 4.4인 FR4를 사용하였다. 실험 결과, 대역폭은 17.2~24.1 %이고, 이득은 3.01~4.71 dB이며, 방사 패턴은 전방향 특성의 결과를 얻었다. 본 논문의 결과를 적용함으로써 휴대 단말기의 가격경쟁력과 생산효율을 향상시킬 수 있다.

• 동아시아식생활학회지
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• 제21권3호
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• pp.429-437
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• 2011

This study evaluated on the purchasing patterns for bakery products and the effects of brand image on consumers' purchasing power while living in the Seoul area. The questionnaires developed for this study were distributed to 400 males and females aged 20 and older. A total of 385 questionnaires were used for analysis (96.0%) and the statistical analysis, descriptive analysis, and $x^2$-test were completed using SPSS (version 14.0) software. When purchasing bakery products, 'taste' (59.7%) was most important followed by 'shape and size' (13.2%), 'ingredients' (11.7%), 'price' (7.5%), 'expiration date' (5.2%). 'origin of ingredients' (2.1%), and 'packaging' (0.5%). Subject showed significant differences in their purchase of bakery products based on characteristics including 'age' (p<0.05), 'occupation' (p<0.01), 'type of family' (p<0.01), and 'income' (p<0.1) The most influential factor in purchasing bakery products was 'material' (score=3.73), followed by 'name value' (score=3.56). Brand image of bakery had an effect on bakery products as 'present' (score=3.83), 'sanitation' (score=3.58). And, the most high respondent in basis of deciding brand image consumer's was 'clean and nice interior'(53.1%), followed by 'high quality ingredients and packaging'(23.7%).

• 복식문화연구
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• 제17권2호
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• pp.255-269
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• 2009

The purpose of this study was to understand the internet fashion shopping behavior of men in their 20s, and to develop the internet shopping website with situation-based clothing coordination services for male comsumer in their 20s. The study was implemented through a normative descriptive survey method using a questionnaire. The survey was conducted in April and May 2006, and the sample group consisted of 280 men in their 20s from Busan and the provinces of Gyeongnam and Gyeongbuk. The data was analyzed by following statistical methods: frequency analysis, one-way-ANOV A, and Scheffe's test. The results are as follow: first, regarding internet the usage trend of male consumers in their 20s, it was shown that they usually spent more than 15 minutes and less than 30 minutes for internet shopping the price range from their experiences of clothing purchases was relatively high for they bought jackets or suits was relatively high. Second, an analysis on men's pattern of clothing purchase showed that many respondents purchase single items such as shirts or pants online. Third, in terms of their experiences of online purchase of coordinated clothes, 69% said "none." Yet, they showed positive assessment to a question whether they are willing to purchase clothes by using a situation-based coordination service or a 1:1 online coordination services. Fourth, the relationship between consumers' reactions to online situation-based clothing coordination services and respondents' demographic characteristics showed statistically significant different results in terms of occupation.

• 복식문화연구
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• 제16권3호
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• pp.444-460
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• 2008

The purposes of this study were to investigate life style and various clothing purchasing behaviors of female consumers, and to analyze the differences of life style and clothing purchasing behaviors by 3 age groups(adolescence, middle age, and senescence). The subjects were 750 adult women aged from twenties to sixties who live in Daejeon and Chungnam province. The research method is a survey and research instruments consisted of life style questionnaire, clothing purchasing behaviors questionnaires, and demographic attribution. Data were analyzed by factor analysis, variance analysis, Duncan's multiple range test and $X^2$ test, using SPSS program. The research results are follows. First, 6 factors were emerged in life style(appearance-oriented, achieve-oriented, social life-oriented, economic- oriented, equality of sexes-oriented, and leisure- oriented). Second, 5 factors were emerged in shopping orientation(resonable shopping, conspicuous shopping, voluptuous shopping, devoted shopping, and convenient shopping). Third, clothing purchasing behaviors of adult women showed many differences by age groups. Adolescence women considered more criterion including design, price, and color or pattern, purchased their clothing by psychological reason such as fashion change, and used internet as important source of clothing, whereas senescence women purchased by physical reason such as body size change and functional trouble, used friend and sales person as important source of clothing, and purchased clothing at department store and old style market.