• Journal of Animal Science and Technology
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• 제63권2호
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• pp.339-353
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• 2021

This study aimed to assess the causality of different climate variables on the production of whole crop maize (Zea mays L.; WCM) in the central inland region of the Korea. Furthermore, the effect of these climate variables was also determined by looking at direct and indirect pathways during the stages before and after silking. The WCM metadata (n = 640) were collected from the Rural Development Administration's reports of new variety adaptability from 1985-2011 (27 years). The climate data was collected based on year and location from the Korean Meteorology Administration's weather information system. Causality, in this study, was defined by various cause-and-effect relationships between climatic factors, such as temperature, rainfall amount, sunshine duration, wind speed and relative humidity in the seeding to silking stage and the silking to harvesting stage. All climate variables except wind speed were different before and after the silking stage, which indicates the silking occurred during the period when the Korean season changed from spring to summer. Therefore, the structure of causality was constructed by taking account of the climate variables that were divided by the silking stage. In particular, the indirect effect of rainfall through the appropriate temperature range was different before and after the silking stage. The damage caused by heat-humidity was having effect before the silking stage while the damage caused by night-heat was not affecting WCM production. There was a large variation in soil surface temperature and rainfall before and after the silking stage. Over 350 mm of rainfall affected dry matter yield (DMY) when soil surface temperatures were less than 22℃ before the silking stage. Over 900 mm of rainfall also affected DMY when soil surface temperatures were over 27℃ after the silking stage. For the longitudinal effects of soil surface temperature and rainfall amount, less than 22℃ soil surface temperature and over 300 mm of rainfall before the silking stage affected yield through over 26℃ soil surface temperature and less than 900 mm rainfall after the silking stage, respectively.

• 문화기술의 융합
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• 제9권3호
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• pp.281-286
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• 2023

본 연구는 서울, 서울 강남, 서울 강북을 대상으로 주택 매매가격과 전세가격의 인과관계를 분석하였다. 시간불변 그랜져 인과성 검정을 통해 분석한 결과, 서울과 강북 지역에서는 매매가격과 전세가격이 양방향 인과성이 있는 것으로 분석된 반면, 강남은 양방향으로 인과성이 없는 것으로 분석되었다. 반면, 시간가변 그랜저 인과성 검정을 통해 분석한 결과에서는 서울, 강남, 강북 지역 모두 1993년 이후 전기간 동안 주택 전세가격은 매매가격에 그랜저 인과관계가 있는 것으로 분석된 반면, 전세가격에 대한 매매가격의 그랜저 인과성이 발견된 빈도는 그 역에 비해 적었다. 특징적인 것은 강남 지역은 2010년 이후 전세가격이 매매가격에 대해 지속적으로 그랜저 인과하는 것으로 분석되었다는 것이다. 이와 같은 분석 결과는 매매시장과 전세시장이 양방향으로 강한 영향을 주고받는 구조에서 전세시장에 대한 유동성 공급 확대는 주택시장 전반에 걸쳐 변동성을 확대할 수 있음을 시사한다.

• 한국간호교육학회지
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• 제14권2호
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• pp.224-231
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• 2008

Purpose: The purpose of this study was to analyze the types of the causal perception of preterm labor. Method: The research design was a Q-Methodological Approach. Thirty four selected Q-statements from 32 participants were classified into a shape of normal distribution using a 9 point scale. The collected data was analyzed using a QUANL PC program. Result: Three types of causal perception for research subjects were identified. Type I is negligence of causality; Type II is recognition of causality by preceding factors. Type III is recognition of causality by psychological stress. Conclusion: This study found that there are differences in perceiving causes of preterm labor. Therefore, it is necessary to develop a tailored nursing intervention depending on these types.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 춘계학술대회논문집
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• pp.855-860
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• 2005

For the accurate measurement of acoustic properties of a surface, efforts have been made to reduce errors caused by external disturbance. If the reflection coefficient is considered as a transfer function between reflected wave and incident wave, causality is required between them and the reflection coefficient should be of minimum phase. In this thesis, the minimum phase condition is applied to measure correct reflection coefficient. The reflection coefficient is approximated as a rational function in the Z domain by minimizing the sum square error. Then the minimum phase reflection coefficient is reconstructed using the distribution of poles and zeros of the reflection coefficient model. The incident wave, the reflected wave and the impulse response function of causality are recalculated from the minimum phase reflection coefficient for further applications.

• The Journal of Asian Finance, Economics and Business
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• 제1권1호
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• pp.5-14
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• 2014

This paper empirically examines the short-run and long-run causal relationship between stock market prices and exchange rates in Chinese stock markets using monthly data from January 2002 to December 2012 retrieved from the National Bureau of Statistics of the People's Republic of China. Unit root, cointegration tests, vector error correction estimates, block exogeneity Wald tests, impulse responses, variance decomposition techniques and structural break tests are employed. This study found 1) long-run causality from exchange rates to stock prices in Chinese stock markets and 2) short-run causality from Japanese yen and Korean won exchange rates to stock prices in the Shanghai Stock Exchange strongly prevails while in the Shenzhen Stock Exchange weakly prevails. The impact of the global financial crisis from 2007 to 2009 on Chinese stock markets was insignificant.

• 조명전기설비학회논문지
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• 제30권3호
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• pp.39-45
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• 2016

In these days global energy policy is changed from "supply" to "demand". In this regards, there are needs to analysis on effect of policy such as energy efficiency strategy, electricity rates. This study examines the relationship between energy consumption reduced by new energy policy and GDP growth for each industrial sector for Korea from 1970 to 2013. With respect to the direction of causality, energy use of 1th industry like agriculture and mining leads to GDP growth. On the other hand, GDP growth of 2nd industry, manufacturing, leads to energy use. And there is bidirectional causality in 3rd industry, service sector. These findings imply that the government policies aimed at reducing electricity consumptions and increasing energy efficiency should be progressed cautiously depend on status of each industry condition.

• 기술혁신학회지
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• 제7권2호
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• pp.257-281
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• 2004

In this paper we： (1) analyze the relationship among public R＆D investment, private R＆D investment, and GDP by employing the Clangor causality test; (2) examine if there is any country-specific pattern in the relationship by testing the cases of Korea, the U.S. and Japan. We found some common results for the above countries as follows： (i) GDP causes Public R＆D, not vice versa; (ii) Private R＆D causes GDP; and (iii) Public R＆D does not cause Private R＆D. For the bivariate model of GDP and total R＆D, the results show the existence of one-way causality running from total R＆D to GDP f3r both U.S. and Japan. We also found bidirectional causal relationship between GDP and total R＆D for Korea, which could be interpreted as a typical pattern for newly industrialized countries.

• 인터넷정보학회논문지
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• 제5권6호
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• pp.67-77
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• 2004

본 논문은 인과성 모델에 기반 한 멀티미디어 동적 저작시스템을 구현하였다. 사용자가 원하는 시나리오를 직관적이고 자연스럽게 프로그램 하도록 2가지 명세를 정의하였다. 인과성을 바탕으로 한 시간 명세는 프리젠테이션에 참여하는 미디어 객체간의 시간관계를 정의한 것이며, 두 번째 명세는 스크린상에 실행되는 미디어들의 상대적인 위치 관계를 토대로 정의한 공간 명세이다. 이 두 가지 사양을 토대로 프리젠테이션 시스템을 구성하였다. 본 시스템의 구성은 멀티미디어 전자문서 생성 과정을 반영한 것이며 그 단계로는 1차원 스트링 리스트 생성 단계, 시간 및 공간 트리 생성 단계, 복합 트리 생성 단계로 구성 처리하였다.

• Journal of Korea Trade
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• 제23권2호
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• pp.34-45
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• 2019

Purpose - This study investigates the lead-lag relations between the prices of major commodities imported into Korea and corresponding shipping freight rates. This paper aims to provide implications for cross-market causal relations between related economic segments. Design/Methodology - For economic long-run equilibrium between commodity prices and freights, a Johansen (1988) cointegration test is employed first. Then, Granger (1987) causality tests are performed under the vector error correction model (VECM) framework. Findings - The results indicate that the direction of causality varies by raw materials, which is attributable to different economic mechanisms in the corresponding shipping transportation sectors. In addition, the significance of causality becomes blurred during the post-2008 period. Practical Implication - Corporate managers in commodity trading, steelmaking, power generation, and oil refinery sectors can take advantage of the findings in this study as identifying leading economic indicators can be helpful for decision making in both short- and long-term strategies. Originality/value - This study is the first attempt to analyze the inter-relations between commodity prices and corresponding freight rates focusing on raw material imports of Korea.

• 한국유기농업학회지
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• 제26권4호
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• pp.571-583
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• 2018

The purpose of this study is to explore the dynamic properties of causality and asymmetric price transmission in the distributional channel of the tomato market in Korea. Using the wholesale and retail price series of the tomato market, we obtain the following results. First, the price transmission mechanism reveals the causal relationship channeling from the wholesale price to the retail price. Second, we find an asymmetric price transmission from the analysis using the threshold partial adjustment model. The retail price responds strongly when the wholesale price increases. On the other hand, the retail price shows sluggish adjustment when the wholesale price decreases.