Green Growth Strategies for Food, Agriculture, Forestry, and Fisheries

Oh Kyung-Tae(오경태) 한국농촌경제연구원 2010 한국농촌경제연구원 연구자료 Vol.- No.-

다중 대역 송신을 위한 디지털 사전 왜곡 기법을 이용한 비선형 전력 증폭기의 고조파 신호 선형화

오경태(Kyungtae Oh),구현철(Hyunchul Ku),김동수(Dongsu Kim),한철구(Cheol-Koo Hahn) 한국전자파학회 2008 한국전자파학회논문지 Vol.19 No.12

본 논문에서는 입력 복소 포락선 신호와 m차 고조파 대역의 출력 복소 포락선 신호 사이의 비선형성 관계를 이론적으로 분석하고, 이를 모델링하기 위하여 AM/AMm, AM/PMm을 정의하였다. 제안된 모델을 측정 데이터로부터 추출하는 방안을 제안하였고, InGaP 전력 증폭기에 대하여 기본 주파수 대역과 3차 고조파 대역에서의 신호를 측정하여 제안된 모델 및 기법의 유효성을 검증하였다. 또한, 제안된 고조파 신호 대역에 대한 모델을 기반으로 고조파 대역 신호의 선형화를 위한 디지털 사전 왜곡 기법을 제안하였다. 디지털 사전 왜곡기에서 비선형 역함수 구현을 위해 수치 해석적인 방법과 Look-Up Table(LUT) 방식을 이용하였다. 고조파 신호 선형화를 위한 디지털 사전 왜곡기를 포함하는 송신기를 구현하고 16-QAM과 64-QAM의 입력 신호에 대해서 3차 고조파 출력신호의 스펙트럼과 I/Q 신호 성상도를 측정하였다. 고조파 대역에서 비선형 왜곡에 의해서 의미 없는 신호는 제안된 기법으로 구성된 송신기에 의해 선형화되었으며, 그 결과 각 신호에 대한 Error-Vector Magnitudes(EVM)이 6.4 %와 6.5 %로 측정되었다. 제안된 기법은 향후 SDR과 CR 등의 차세대 다중 대역 송신 시스템에 적용될 수 있을 것으로 사료된다. In this paper, a nonlinear relationship between an input complex envelope and an output complex envelope of m-th harmonic zone is theoretically analyzed, and AM/AMm and AM/PMm are defined. A scheme to extract these characteristics from measured in-phase and quadrature-phase data is suggested. The proposed analysis is verified with a fundamental-fundamental and fundamental-third harmonic measurements for a InGaP power amplifier(PA). Based on the harmonic-band nonlinear analysis and extraction scheme, a new technique to send a signal in m-th harmonic band with a harmonic signal Linearization Digital Predistortion(DPD) scheme is presented. A numerical analysis and a Look-Up Table(LUT) based DPD algorithms to linearize output signal on m-th harmonic zone are developed. For a 16- and a 64-QAM input signals, a DPD for third harmonic signal linearization is implemented, and output spectrum and signal constellation are measured. The wholly distorted signals are linearized, and thus the measured Error Vector Magnitudes (EVM) are 6.4 % and 6.5 % respectively. The results show that a proposed scheme linearizes a nonlinearly distorted harmonic band signals. The proposed nonlinear analysis and predistortion scheme can be applied to multiband transmitter in next generation software defined radio(SDR)/cognitive radio(CR) wireless system.

농림수산식품 『녹색성장 추진전략』

오경태(Oh Kyung-Tae) 한국농촌경제연구원 2010 한국농촌경제연구원 연구자료 Vol.- No.-

신발산업의 네트워크형성요인,관계몰입 및 조직유효성 간의 구조관계에 관한 연구

오경태(Oh, Kyung Tae),천종기(Cheon, Jong Ki),서정기(Seo, Jung Gi),신용존(Shin, Yong John) 한국인적자원관리학회 2010 인적자원관리연구 Vol.17 No.1

본 연구는 신발산업의 네트워킹과 관련하여 네트워크조직의 의의,네트워크조직의 형성과 관련된 이론,네트워크조직의 관계몰입 그리고 네트워크조직 유효성 동을 고찰하고 그 메커니즘에 대한 실증적 검증을 시도함으로써 네트워크조직 형성의 영향요인과 관계몰입,그리고 조직유효성의 구조적 관계에 있어서 각각의 변수가 서로 어떠한 영향을 미치는지 검토하였다. 실종분석결과 네트워크조직 형성 영향요인으로서의 신뢰,정보공유,경쟁,그리고 상호의존성은 네트워크 관계몰입에 정의 영향을 미치는 것으로 실증되었고,나아가 네트워크 관계몰입은 관계만족도와 관계지속성의 네트워크 조직유효성에 정의 영향을 미치는 것으로 나타났다. Currently, Many footwear companies in Busan have chosen the cooperation relationship through the network organization as a way to survive in dynamic changing business environment. This situation needs to understand the meaning or significance of network organization, main theories with construction of network, many studies concerning relationship quality and effectiveness of network orgarnization. The research problem of this study are two issues about how do which factors constructing network organization effect on the relationship commitments of it, and how do those commitments effect on the effectiveness of it. Therefore, the primary purpose of this study is to verify empirically the mechanism of the network organization in Korean footwear industry, focused on relationship among firms participating in the network.According to this research model, the following hypotheses are able to be developed for the statistical tests: Hypothesis 1: The influencing factors of constructing network organization would have an effect on positively the relationship commitment of network organization in footwear industry Hypothesis 2: The relationship commitment of network organization would have an effect on positively the effectiveness of network organization in footwear industry. The result of statistical analysis shows the basis to be able to adopt hypothesis 1 and 2 by the structural equation modeling. It is clear therefore the analytic result shows considerable statistical significance. The result of test in hypothesis 1 shows that when trust, information sharing between participated firms, circumstances of market competition, and interdependence with partner firm at influencing factors of constructing network are higher, relationship commitment of network organization would be higher. However it shows that the factor of market transaction cost does not effect on relationship commitment. The result of test in hypothesis 2 shows that when the relationship commitment is higher, relationship satisfaction and continuance of network organization would be higher. This means the relationship commitment leads positive effect on effectiveness of network organization.

Class E 기법을 이용한 소나용 고효율 전력증폭기 분석 및 설계

이영섭(Y. S. Lee),오경태(K. T. Oh),구현철(H. C. Ku),목형수(H. S. Mok),허정(J. Hur),이강윤(K. Y. Lee) 전력전자학회 2007 전력전자학술대회 논문집 Vol.- No.-

본 논문에서는 소나용 고출력 전력증폭기의 효율을 향상시키기 위하여 Class E 설계 기법을 분석하고 소나 시스템의 송신기에 적용하였다. Class E 기법에 기반하여 전력소자를 스위칭 모드로 동작시켜서 Zero Voltage Switching(ZVS)이 발생하도록 회로를 설계함으로써 전력 소자의 전력 손실을 최소화하고 전력 증폭기의 효율을 최대화하여 주었다. 설계된 Class E 기법의 전력 증폭기의 동작 및 타당성을 시뮬레이션을 통하여 검증하였다.

조사논문 : 한국인의 쇠고기 소비패턴 -거주 국가에 따른 비교분석-

이종인 ( Jong In Lee ),( Zhi Feng Gao ),오경태 ( Kyung Tae Oh ),오송련 ( Song Lian Wu ),신동민 ( Dong Min Shin ),이정숙 ( Jeong Suk Lee ),최종산 ( Jong San Choi ),김희걸 ( Xi Jie Jin ) 한국축산경영학회,농업정책학회(구 한국축산경영학회) 2014 농업경영정책연구 Vol.41 No.4

Koreans prefer Korea beef to imported beef. The volume of imported beef is being increased in Korea. Consumers preference may be changed when they consume the imported beef more. The purposes of this study are to analyze the changes of the Koreans`` preference and perception to Korean beef and imported beef. Koreans who are living in Korea prefer Korean beef to imported beef. However, Koreans who are living in U.S.A. may prefer U.S. beef or keep neutral between the two kinds of beefs. Questionnaire were given to Koreans who were living in Korea and U.S.A. from January to April in 2014. SPSS 18.0 was used for the analyses. T-test was used for comparative analysis by living country about beef and multiple regression analysis was used for analyzing impacts of age and period of reside in United States to quality evaluation about Korean beef and U.S. beef. In the result, Korean consumers had differences in all perception variables about U.S. beef by living country, but hadn``t in Korean beef. And Korean consumers living in Korea and United States evaluated that Korean beef had better quality than U.S. beef. Finally, only period of reside in United States had positive impacts to perception of U.S. beef quality. Korean beef should try to keep high quality and image. Government need to active support and intensive control beef traceability system and origin labeling. Imported beef market may be expanded in the future. So prepare countermeasure for low-grade Korean beef about increasing of the imported beef in Korean market.

연구논문 : 해외시장 공략을 위한 국내업체, 관련기관, 정부와의 연동전략

송경수 ( Kyung Soo Song ),박흥주 ( Heung Ju Park ),오경태 ( Kyung Tae Oh ) 한국인적자원관리학회 2003 인적자원관리연구 Vol.6 No.-

동물복지형 달걀에 대한 광고매체의 효율성 분석

오상집(Sang Jip Ohh),정윤필(Yun-Pil Jung),오경태(Kyung-Tae Oh),홍승지(Seung-Jee Hong),이종인(Jong-In Lee) 충남대학교 농업과학연구소 2012 농업과학연구 Vol.39 No.3

The object of this study is to establish proper consumer-oriented advertisement strategies of animal welfare egg. Data were collected by consumer survey on November 4th, 2011 at Hanaromart in Chunchon area. SAS 9.1 and Excel 2007 were used as statistical package and ranked logit model was used to analyze the data. From the results of the study the following advertisement strategies were suggested for animal welfare egg considering the effects of advertisement media. First, internet based media were most preferred. For effectively using the internet based media the message should be succinctly and clearly transferred to consumers. Therefore if phrases and pictures emphasizing the difference between animal welfare egg and general egg were used, then positive effects could be attained from consumers in a short period. Second, advertisement media should be used differently based upon the consumers" income level. In the case of consumers under three million won income level the advertisement in the purchasing site was most effective regarding the advertisement effects. Therefore if the advertisement showing the breeding surroundings between animal welfare egg and general egg was used, positive effects could be attained. For consumers over three million won income level the homepage of egg producers was most effective in advertisement. So if more accurate information were distributed to consumers visiting the homepage and high quality egg were sold via the homepage, positive effects could be attained.