• 인터넷정보학회논문지
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• 제6권5호
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• pp.143-154
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• 2005

본 논문은 무선 엑세스 포인트를 기반으로 사용자가 광고 컨텐츠 수신을 통해 무선 네트워크 접속 서비스를 받을 수 있는 인터넷 접근형 광고 시스템에서 신뢰적 멀티캐스트 전송에 관한 것이다. 본 논문에서는 무선 LAN 환경에서 신뢰성 있는 멀티캐스트를 위해 네트워크 상태에 따라 이동단말기의 전송량을 조절하는 응용 계층 멀티캐스트 프로토콜을 제안한다. 인터넷 광고란 상품 또는 서비스의 판매나 인지도를 높이기 위하여 인터넷의 운용 프로그램이나 서비스 등을 광고 매체로 제공하는 광고 메시지를 통칭한다. 기존의 인터넷 광고 시스템들은 대부분 유선 환경의 불특정 다수를 대상으로 광고를 하며, 사용자의 웹브라우저를 광고 표현 매체로 하기 때문에 임의로 접근하는 사이트에 따라 노출 빈도가 매우 달라지는 수동적인 방법이다. 더욱이 사용자가 광고를 보아야 하는 필연적인 이유가 없으므로 광고가 사용자들에게 얼마나 효과적으로 노출될 수 있느냐 하는 문제점을 가지고 있다. 본 논문에 따른 인터넷 광고 시스템을 사용할 때, 사용자들은 무선 인터넷을 무료로 이용하고 광고주들은 사용자들에게 타겟 마케팅을 위한 지역적(현장성), 시간적(즉시성), 카테고리별(개인성) 타겟 광고를 하며, 네트워크 인프라 소유자는 기존 네트워크 인프라의 변경을 최소화하여 저비용으로 인터넷 광고 시스템을 운영할 수 있다.

• Environmental Analysis Health and Toxicology
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• 제30권
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• pp.15.1-15.11
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• 2015

Objectives There has been a growing concern about the possible carcinogenic effects of the electromagnetic radiofrequency fields emitted from mobile phones. The purpose of this study was to investigate the association between mobile phone use and the development of gliomas in Korea. Methods Our study methods were based on the International Interphone study that aimed to evaluate possible adverse effects of mobile phone use. This study included 285 histologically-confirmed Korean patients 15 to 69 years of age, with gliomas diagnosed between 2002 and 2007 in 9 hospitals. The 285 individually matched controls were healthy individuals that had their medical check-up in the same hospitals. Unconditional logistic regression was used to calculate the adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for use of mobile phones. Results For the entire group, no significant relationship was investigated between gliomas and regular use of mobile phones, types of mobile phones, lifetime years of use, monthly service fee, and the other exposure indices. Analyses restricted to self-respondents showed similar results. For ipsilateral users, whose the body side for usual mobile phone use match the location of glioma, the aORs (95% CIs) for lifetime years of use and cumulative hours of use were 1.25 (0.55 to 2.88) and 1.77 (0.32 to 1.84), respectively. However, the contralateral users showed slightly lower risk than ipsilateral users. Conclusions Our results do not support the hypothesis that the use of mobile phones increases the risk of glioma; however, we found a non-significant increase in risk among ipsilateral users. These findings suggest further evaluation for glioma risk among longterm mobile phone users.

• Advances in Energy Research
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• 제5권2호
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• pp.107-128
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• 2017

Energy is a major component of almost all economic, production, and service activities, and rapid population growth, urbanization and industrialization have led to ever growing demand for energy. Limited energy resources and increasingly evident environmental effects of fossil fuel consumption has led to a growing awareness about the importance of further use of renewable energy sources in the countries energy portfolio. Renewable hydrogen production is a convenient method for storage of unstable renewable energy sources such as wind and solar energy for use in other place or time. In this study, suitability of 25 cities located in Iran's western region for renewable hydrogen production are evaluated by multi-criteria decision making techniques including TOPSIS, VIKOR, ELECTRE, SAW, Fuzzy TOPSIS, and also hybrid ranking techniques. The choice of suitable location for the centralized renewable hydrogen production is associated with various technical, economic, social, geographic, and political criteria. This paper describes the criteria affecting the hydrogen production potential in the study region. Determined criteria are weighted with Shannon entropy method, and Angstrom model and wind power model are used to estimate respectively the solar and wind energy production potential in each city and each month. Assuming the use of proton exchange membrane electrolyzer for hydrogen production, the renewable hydrogen production potential of each city is then estimated based on the obtained wind and solar energy generation potentials. The rankings obtained with MCDMs show that Kermanshah is the best option for renewable hydrogen production, and evaluation of renewable hydrogen production capacities show that Gilangharb has the highest capacity among the studied cities.

• 로봇학회논문지
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• 제2권1호
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• pp.40-47
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• 2007

Recently, with the development of service robots and with the new concept of ubiquitous world, the position estimation of mobile objects has been raised to an important problem. As pre-liminary research results, some of the localization schemes are introduced, which provide the absolute location of the moving objects subjected to large errors. To implement a precise and convenient localization system, a new absolute position estimation method for a mobile robot in indoor environment is proposed in this paper. Design and implementation of the localization system comes from the usage of active beacon systems (based upon RFID technology). The active beacon system is composed of an RFID receiver and an ultra-sonic transmitter: 1. The RFID receiver gets the synchronization signal from the mobile robot and 2. The ultra-sonic transmitter sends out the traveling signal to be used for measuring the distance. Position of a mobile robot in a three dimensional space can be calculated basically from the distance information from three beacons and the absolute position information of the beacons themselves. Since it is not easy to install the beacons at a specific position precisely, there exists a large localization error and the installation time takes long. To overcome these problems, and provide a precise and convenient localization system, a new auto calibration algorithm is developed in this paper. Also the extended Kalman filter has been adopted for improving the localization accuracy during the mobile robot navigation. The localization accuracy improvement through the proposed auto calibration algorithm and the extended Kalman filter has been demonstrated by the real experiments.

• 한국정보통신학회논문지
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• 제21권11호
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• pp.2043-2051
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• 2017

최근 빅데이터 분야의 높아진 관심과 더불어 빅데이터의 처리를 통한 응용 분야에 대한 관심도 높아지고 있다. 개인의 감성을 파악할 수 있는 오피니언마이닝은 사용자 개인 맞춤 서비스 제공 분야에서 많이 이용되고 있는 빅데이터 처리 기법이다. 이를 바탕으로 본 논문에서는 사용자들의 장소에 대한 텍스트 형태의 리뷰를 오피니언마이닝 기법으로 처리하고 k-means 클러스터링 작업을 통해 사용자의 감성을 분석하였다. 클러스터링 작업으로 분류된 비슷한 범주의 감성을 가진 사용자들끼리 동일한 수치 값을 부여한다. 부여된 수치 값으로 협업 필터링 추천 시스템을 이용해 선호도를 예측하고 예측 값이 높은 장소 순으로 지도위에 마커와 함께 내용을 표시하여 사용자에게 추천내용을 보여줄 수 있는 방안을 제안하였다.

• 농촌계획
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• 제23권2호
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• pp.55-65
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• 2017

This study is to estimate the circuity factors which can be used to assess for public facilities accessibility and analyze traffic in the area. We set the range of the administrative districts by Si Gun Gu unit and Eup Myeon Dong unit (more subdivided unit than Si Gun Gu unit). The average circuity factor in Si Gun Gu unit is 1.364 (maximum 2.953 and minimum 1.711). The region indicated the highest value of circuity factor is wando-gun in jeollanam-do, which area consists of 4 island and is connected to the bridges. Having to use the bridges for using public facilities hinders its accessibility. In the case of Eup Myeon Dong unit, the average circuity factor is 1.353 (maximum 2.950 and minimum 1.154). The region indicated the highest value of circuity factor is buksan-myeon in chuncheon-si, Gangwon-do. This region also has to use bridges for using public facilities because there is the largest lake, called Soyangho. This circuity factor is used to analyze the location of public facilities and assess vulnerability of accessibility. And also the factor can be applied to some policies, such as rural public service planning based on spatial big data.

• 한국전자거래학회지
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• 제17권3호
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• pp.1-14
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• 2012

전자 정보 기술이 발전함에 따라, 스마트폰의 계산 능력은 더욱 막강해지고 저장장치의 용량은 더욱 거대해지고 있다. 이에 따라, 유용한 새로운 스마트폰 서비스가 많이 등장하고 있는데, 상황인지 서비스와 모바일 증강 현실이 근래에 가장 많이 연구되고 있는 대표적인 주제이다. 이러한 새로운 서비스에서 스마트폰에 장착된 카메라로 촬영한 사진 속의 개체를 인지하는 것은 매우 중요한 역할을 수행한다. 그래서 사진을 인지하는 연구가 많이 출판되었는데, 대부분은 처리 시간이 매우 긴 이미지 인지 기술 기반이다. 이와 반대로, 본 논문은 스마트폰의 센서로부터 수집한 데이터와 전자지도를 이용하여 사진 속의 개체를 인지하는 매우 빠르고 효율적인 방법을 제안한다. 제안하는 방법은 스마트폰이 제공하는 현재 위치와 방향각으로 카메라의 시선을 구하고, 카메라 시선과 교차하는 전자지도의 요소들을 찾는다. 그리고 교차하는 요소들을 조사하여 사진 속의 개체를 인지한다.

• 가족자원경영과 정책
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• 제22권3호
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• pp.61-76
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• 2018

The demand and supply of programs of parenthood programs for fathers are increasing with changes in the image of male parents. Under this backdrop, a necessary requirement is to analyze the current status of father programs that are spearheaded by governments and the satisfaction with them to determine if they actually meet the needs of fathers. This study conducted such an examination for the fatherhood programs that were provided as a mandatory public service by the Healthy Family & Multicultural Family Support Center in 2017. To this end, the research analyzed performance and satisfaction data on 776 projects, including 1293 programs that were required for provision in 101 integrated centers nationwide. The results showed that satisfaction with fatherhood programs differed according to the project area, the location of a center, the period of implementation, the methods of proceeding, the participation unit (whether an entire family or an individual family member), the number of participants, and the number of sessions. Overall, the level of satisfaction was higher in "fathers meetings" (under the community domain) than "support for the father role" (under the family relationship domain). In relation to implementation period, satisfaction with the programs was high in the 4th quarter of implementation. Satisfaction with the programs was also higher for culturally based initiatives than education-oriented programs. Satisfaction was higher when the participation unit was the family than when such unit was the individual. The smaller the number of participants, the higher the satisfaction level. Finally, the number of sessions was deemed satisfactory when it was completed in more than four sessions. This study is meaningful in that it provides the basis of effective use of the government budget by analyzing the status and satisfaction of the fatherhood programs, which have been implemented since the integration of the Healthy Families & Multicultural Family Support Center.

• 한국인터넷방송통신학회논문지
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• 제17권6호
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• pp.137-143
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• 2017

횡단보도와 교차로에서 시각 장애인을 위한 보행 안전시설은 부족하다. 시각 장애인을 위해 인도에 점자 블록이 설치되고 교차로에 RF 원격 제어 시스템으로 제어되는 신호등과 음향 신호기가 설치되어 있다. RF 원격 제어 시스템은 하나의 주파수를 사용하여 교차로에서 인접한 신호등과 음향 발생기들을 동시에 동작시키는 문제가 있다. 본 논문은 비콘을 사용하여 교차로에 설치된 시각 장애인을 위한 신호등과 음향 신호기를 식별하고 진행 방향의 신호등과 음향 신호기를 적외선 통신으로 동작시키는 스마트 지팡이를 개발하였다. 본 논문에서 개발한 스마트 지팡이는 블루투스 통신을 통해 모바일 앱과 연동하여 시각 장애인을 위한 보행자 내비게이션을 제공 할 수 있다.

• 통상정보연구
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• 제11권2호
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• pp.343-367
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• 2009

This research is about global investment for managing the important position, what Korea is doing in World's main market. Considering there are some differences between developed countries' model and developing countries' model in doing direct overseas investment, they target to get political agreement and develop the new invest plan and strategy by understanding changes of Korean manufacturing companies in direct overseas investment between 2000 and 2007 and analyzing the change of yearly investment motivation factors and determining factors for investment. The result from this result let us know that company should develop their own idea for their competitive advantage by doing direct overseas investment with the existing theory which convinces the need of competitive advantage for investing overseas. I set actual model and analyze results from it with the considering that it is so important to get knowledge and information for globalizing companies to invest overseas and companies, which want to be world leading ones for their field through innovation and changes, need to have more active strategy. And, the overseas investment, which was already done in other countries, 1. Review its realities and tendency in terms of investing countries, investing industries, and its scale. 2. Set up an actual model, based on strategic combination of investing location select and determination of Korean manufacturing companies and yearly investing factor-effect analysis. 3. Analyze how the situational factors have influenced and what factors would be considered for direct overseas investment. From the analyzing result, even though it is fairly true that raising wage and getting resources, avoiding customs, and developing alternating industries for export had influenced at the beginning, overseas investing companies' policy will be influenced by the results from studying marketing-pursuit type, which emphasizes to manage trade income and outgo, keeping the balance in the black, ensuring raw materials, local producing and manufacturing by using low-wage people for local sale, and situation for changing investing tendency as service industry.