• 정보과학회 컴퓨팅의 실제 논문지
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• 제22권10호
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• pp.513-520
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• 2016

IoT 기기가 대중들에게 보급화 됨에 따라서 임베디드 시스템의 성능뿐만 아니라 소모하는 에너지에 관한 문제가 중요하게 대두되고 있다. 이는 특히 휴대용 임베디드 기기에서 더 중요한데, 휴대용 임베디드 기기들은 각 디바이스들이 가지고 있는 배터리를 통하여 전원을 얻기 때문에 얼마나 효율적으로 잘 사용하는지가 곧 시스템의 사용시간으로 귀결되기 때문이다. 본 논문에서는 임베디드 리눅스 시스템에서의 에너지 소모량을 줄이기 위하여 디바이스의 frequency를 조절해주는 주파수 변경 프레임 워크를 통하여 최고의 에너지 효율을 갖는 메모리 frequency를 찾고, 메모리 총 사용량을 통한 새로운 디바이스 주파수 변경 기법을 제안한다. 실험을 통해 본 논문에서 제안하는 정책은 이전의 정책과 비교하여 최악의 경우에도 나쁜 에너지 효율을 보이지 않으며 최대 18%의 에너지 감소율을 보였다.

• 토지주택연구
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• 제3권3호
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• pp.263-270
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• 2012

정부는 2009년부터 녹색뉴딜사업의 일환으로 국토 에너지 수자원 건물 등의 각종 기본정보를 체계적으로 일원화시키고 통합 DB를 구축하는 녹색국가 정보인프라 사업을 추진 중에 있다. 이와 관련하여 건물부문의 에너지 절약과 온실가스 저감 대책 마련에 효율적으로 대응하기 위한 수단으로, 건물단위의 에너지 소비량 관리를 기본 골자로 하는 건물에너지 통합관리시스템 구축을 진행 중에 있다. 본 시스템의 활용성을 증대시키기 위해서는 기존의 에너지 정책 및 제도와의 관계를 명확히 하고 상호보완적인 요소를 도출하는 것이 요구되며 이는 통합관리시스템의 구축방향성과도 밀접한 관계를 가진다. 따라서 본 연구에서는 장기적 측면에서 국가 건물에너지 통합관리시스템의 효과적인 활용방안을 도모하기 위하여 현재 진행중인 관련 정책 ,제도 및 통계자료 등과의 연계성을 도출하고, 통합관리시스템의 구축방안 및 방향성을 도모하고자 한다. 구체적으로는 온실가스 관련 정책, 녹색 건축물 보급 확대 방안 및 통계자료 등의 사례를 분석하고 통합관리시스템을 통한 해당 정책 및 제도의 개선점을 개선, 보완할 수 있는 방안을 제시함으로서 통합관리시스템의 구축과 운영방안 수립의 당위성을 재고시키며 향후 녹색뉴딜 사업의 육성을 도모하고자 한다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2011년도 춘계학술대회
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• pp.382-385
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• 2011

최근 유비쿼터스 컴퓨팅의 핵심 기술인 센서 네트워크 기술이 각광을 받으면서 다양한 종류의 센서 노드로 구성된 센서 네트워크에 대한 연구가 활발히 진행되고 있다. 센서 네트워크에서 센서 노드를 디자인할 때 중요한 고려사항 중 하나가 제한된 자원을 가진 센서 네트워크에서 주어진 에너지 소모를 최소화 하여서 네트워크 수명을 연장하는 것이다. 본 논문에서는 센서 노드의 에너지 소모를 줄이기 위해 2계층 클러스터 구조를 사용한 라우팅 프로토콜을 제안한다. 1계층에서는 기존의 LEACH 기반 라우팅 프로토콜을 그대로 사용하며, 2계층에서 효율적인 사용을 위해 데이터의 값의 비교판단으로 송신 여부를 결정함으로서 불필요한 에너지 소모를 줄일 수 있다.

• 한국자동차공학회논문집
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• 제20권6호
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• pp.46-51
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• 2012

Fuel Cell Hybrid Vehicles (FCHVs) have become a major topic of interest in the automotive industry owing to recent energy supply and environmental problems. Several types of power management strategies have been developed to improve the fuel economy of FCHVs including optimal control strategy based on optimal control theory, rule-based strategy, and equivalent consumption minimization strategy (ECMS). The ECMS is applied in this study. This strategy is based on the heuristic concept that the usage of the electric energy can be exchanged to equivalent fuel consumption. This strategy is known as one of the promising solutions for real-time control of hybrid vehicles. The ECMS for an FCHV is introduced in this paper as well as the equivalent fuel consumption parameter. The relationship between the battery final state of charge (SOC) and the fuel consumption while changing the equivalent fuel consumption parameter is obtained for three different driving cycles. The function of the equivalent fuel consumption parameter is also discussed.

• 한국식생활문화학회지
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• 제16권3호
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• pp.195-202
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• 2001

This study was performed to investigate the pattern of health food usage of the adults by food lifestyles pattern in contemporary Seoul. This study views health food consumption as a cultural practice in which people produce (and reproduce) diverse social relationships and cultural meanings. It also identifies food lifestyles and health food usage pattern of Korean adult in Seoul. This topics were discussed based on field research data collected by nutritional survey with questionnaire. To identify the relationships between pattern of health food and food lifestyles, 503 men and 437 women aged 18 to 65 years were divided into 5 groups of food lifestyles : Health Eaters, In-a-Dither, Traditional Eaters, Conscientious and People on the Go. As a substantial percentage of the subjects were used some kinds of nutrients supplement. The higher the age and family income were, the higher the percentage of health food usage was. There was the significant difference between sexes in usuage of health food. Health food usage was higher in the food lifestyle pattern of Health Eater than other food lifestyles.

• 한국지역사회생활과학회지
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• 제27권3호
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• pp.371-385
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• 2016

This study was carried out to provide basic data for the promotion of the educational and social relations of adult learners and the effective way to use the smartphone. To accomplish this, we studied the influence of the degree of smartphone usage on the educational and social relations of college students in the area of Kyung-In and the mediator effect of smartphone addiction. According to this study, the research results were as follows: Firstly, the degree of smartphone usage did not directly affect family relationships, but highly affected smartphone addiction; smartphone addiction had both a negative effect on family relationships and a negative mediator effect between the degree of smartphone usage and family relationships. Secondly, smartphone addiction negatively affected the relationships with the opposite sex, whereas the degree of smartphone usage did not; however, there was a negative mediator effect between the time of using the smartphone and relations between the sexes. Thirdly, smartphone addiction negatively affected relationship with friends, whereas the degree of smartphone usage did not; there was no mediator effect between the time of using the smartphone and relationship with friends. Fourthly, smartphone addiction negatively affected the relationship with professors, whereas the degree of smartphone usage did not; there was no mediator effect between the time of using the smartphone and relationship with professors. The implications of these results are discussed.

• 한국작물학회지
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• 제62권3호
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• pp.157-165
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• 2017

Being a staple food for more than half of the population of the world and South Korea, rice is an important crop. For the past 20 years, global paddy rice cultivation area and production have shown an annual growth of 0.46% and 1.61%, respectively. Global rice consumption for food and processing has increased by 1.37% and 3.68%, respectively. Due to the main reason for such increasing human population, it is expected that from 439 million tons in 2010, additional 116 million tons will be needed in 2035. Global rice imports and exports have doubled in the last 20 years. However, in spite of such increment, global rice exports in 2013 were 8.4% of the total production. It is thought that rice protection policies in the producing countries are the main reason for such small scale of rice trading. In the past 5 years, India recorded the largest growth rate in rice exports (51.4%), whereas China showed the largest growth rate in imports (61.0%). For global utilization of milled rice during the same period, approximately 79.4% was used as food, 7.2% as animal feeds, and 1.4% for processing. Regionally, Asia has shown a similar pattern to the global rice usage, whereas utilization for processing in America, for food in Africa, and for animal feed in Europe was relatively higher than the global rice usage. Korea's cultivation area and production since the last 5 years, are 0.5% and 0.8% of those of the world, respectively. Its annual rice export is approximately 3,000 tons, which is 0.01% of the global rice export. Korea's rice utilization is high for food and low for feed and for processing relative to global rice utilization. Therefore, a review must be conducted to increase Korea's utilization of rice for processing and for feed production.

• Human Ecology Research
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• 제56권6호
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• pp.555-571
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• 2018

This study identified the characteristics of fashion rental service users as well as analyzed their purchase decision-making processes. A qualitative investigation was conducted through in-depth interviews with 13 women in their 20s-30s who have experienced renting fashion items due to a high interest in fashion. The results of the study are summarized as follows. The need recognition stage analyzed ventilation by mass media, SNS impact, curiosity, saving shopping time and money, awareness of situational necessity, and creation of various styles. The information search stage analyzed how users obtained information from 2 different sources of nonmarketer-dominated sources and marketer-dominated sources. The pre-purchase stage analyzed the evaluation of alternatives in which study participants used 2 evaluation criteria for fashion rental services and fashion rental items. The purchase stage analyzed how participants wait and select desired items (when receiving the notification of rentable items) or select alternative products. The consumption stage examined the usage frequency and usage method. The study divided the post-consumption evaluation stage into 2 categories for evaluation: personal feelings and service. The post-consumption behavior stage analyzed how participants displayed WOM, eWOM and purchase rental product behavior. Clothing shopping orientation of study participants is displayed in 5 dimensions of brand-seeking propensity, individuality-seeking propensity, economic efficiency-seeking propensity, rationality-seeking propensity, and pleasure-seeking propensity. This study identified three main characteristics in the study participants: interest in the fashion, favorable attitude toward used fashion items, consciousness of others.

• Journal of Biosystems Engineering
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• 제10권1호
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• pp.69-75
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• 1985

배합사료생산(配合飼料生産)에 소요(所要)되는 운전비용(運轉費用)을 추정(推定)하기 위(爲)하여 소요(所要)에너지, 소요노동력(所要努動力), 유지(維持) 및 수리비(修理費)를 분석(分析)하여 공장규모(工場規模) 및 사료생산종류(飼料生産種類)에 따른 수학적모형을 개발(開發)하였다. 에너지비용(費用)은 전기비용(電氣費用)과 연료비용(燃料費用)으로 구분(區分)하였으며 소요노동력(所要努動力)은 생산노동력(生産努動力), 관리자노동력(管理者努動力) 그리고 유지(維持) 및 수리노동력(修理努動力)으로 구분(區分)하였다.

• 대한간호학회지
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• 제54권2호
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• pp.193-210
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• 2024

Purpose: The objective of this study was to develop a predictive model for the sexual experiences of adolescents using the random forest method and to identify the "variable importance." Methods: The study utilized data from the 2019 to 2021 Korea Youth Risk Behavior Web-based Survey, which included 86,595 man and 80,504 woman participants. The number of independent variables stood at 44. SPSS was used to conduct Rao-Scott χ² tests and complex sample t-tests. Modeling was performed using the random forest algorithm in Python. Performance evaluation of each model included assessments of precision, recall, F1-score, receiver operating characteristics curve, and area under the curve calculations derived from the confusion matrix. Results: The prevalence of sexual experiences initially decreased during the COVID-19 pandemic, but later increased. "Variable importance" for predicting sexual experiences, ranked in the top six, included week and weekday sedentary time and internet usage time, followed by ease of cigarette purchase, age at first alcohol consumption, smoking initiation, breakfast consumption, and difficulty purchasing alcohol. Conclusion: Education and support programs for promoting adolescent sexual health, based on the top-ranking important variables, should be integrated with health behavior intervention programs addressing internet usage, smoking, and alcohol consumption. We recommend active utilization of the random forest analysis method to develop high-performance predictive models for effective disease prevention, treatment, and nursing care.