• KOREAN POULTRY JOURNAL
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• v.30 no.7 s.345
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• pp.92-95
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• 1998

• Cement
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• s.1
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• pp.55-59
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• 1963

• KDI Journal of Economic Policy
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• v.12 no.4
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• pp.47-69
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• 1990

Using an aggregator model, we look into the possibilities for substitution between Korea's exports, imports, domestic sales and domestic inputs (particularly labor), and substitution between disaggregated export and import components. Our approach heavily draws on an economy-wide GNP function that is similar to Samuelson's, modeling trade functions as derived from an integrated production system. Under the condition of homotheticity and weak separability, the GNP function would facilitate consistent aggregation that retains certain properties of the production structure. It would also be useful for a two-stage optimization process that enables us to obtain not only the net output price elasticities of the first-level aggregator functions, but also those of the second-level individual components of exports and imports. For the implementation of the model, we apply the Symmetric Generalized McFadden (SGM) function developed by Diewert and Wales to both stages of estimation. The first stage of the estimation procedure is to estimate the unit quantity equations of the second-level exports and imports that comprise four components each. The parameter estimates obtained in the first stage are utilized in the derivation of instrumental variables for the aggregate export and import prices being employed in the upper model. In the second stage, the net output supply equations derived from the GNP function are used in the estimation of the price elasticities of the first-level variables: exports, imports, domestic sales and labor. With these estimates in hand, we can come up with various elasticities of both the net output supply functions and the individual components of exports and imports. At the aggregate level (first-level), exports appear to be substitutable with domestic sales, while labor is complementary with imports. An increase in the price of exports would reduce the amount of the domestic sales supply, and a decrease in the wage rate would boost the demand for imports. On the other hand, labor and imports are complementary with exports and domestic sales in the input-output structure. At the disaggregate level (second-level), the price elasticities of the export and import components obtained indicate that both substitution and complement possibilities exist between them. Although these elasticities are interesting in their own right, they would be more usefully applied as inputs to the computational general equilibrium model.

• Environmental and Resource Economics Review
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• v.8 no.1
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• pp.95-129
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• 1998

한국은 1990년대에 들어서면서 자본이동을 자유화함에 따라 환율의 급격한 변동을 경험하고 있으며 이로 인하여 원유수입가격(原油輸入價格)의 변동을 경험하고 있다. 본 연구는 이러한 원유수입가격의 변동이 수출입에 주는 효과를 분석하기 위하여 1990년부터 1996년까지의 수요 중심의 월별 거시모형을 구축하여 국제원유가격변동으로 인한 원유수입가격 변동효과와 환율 변동으로 인한 원유수입가격 변동효과를 분석하였다. 분석 결과에 의하면 수출의 경우 국제원유가격 상승시는 단기에 -0.06% 감소하다가 그 효과가 없어지는 데 비해, 환율 상승시는 단기에 -1.84% 감소하다가 장기에 0.36%까지 증가하는 J-curve 현상을 보이고 있다. 원유수입(原油輸入)의 경우 국제원유가격 상승시는 원유(原油)가 비경쟁적 수입이므로 단기에 3.91% 증가하여 장기까지 그 수준을 유지하며, 환율 상승시는 수출과 산업생산의 영향으로 단기에 -7.5%까지 감소하다가 점차 증가하여 장기에는 0.39%까지 증가하는 추세를 보이고 있다. 원유외수입(原油外輸入)의 경우도 국제원유가격 상승시에는 장기에 -0.35% 감소하나 환율 상승시에는 수출과 산업생산의 영향으로 단기에 -4.60%까지 감소하고 장기에는 -0.15% 감소하고 있다. 결국 원유를 포함한 수출입은 국제원유가격 상승시보다 환율 변동시 더 큰 변동을 보이고 있음을 알 수 있다.

• Annual Conference of KIPS
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• 2020.11a
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• pp.953-955
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• 2020

공컨테이너(Empty Container)는 적컨테이너(Full Container)와 달리, 화물이 적재되지 않은 비어있는 컨테이너로 공컨테이너 재고는 수출에 비해 수입이 많은 항만에서, 수요는 수입에 비해 수출이 많은 항만에서 발생한다. 그러나 수입과 수출은 기간, 지역에 따라 유동적이기 때문에 수요와 재고량 예측에 어려움이 있는데, 본 연구에서는 자기회귀누적이동평균(ARIMA)과 머신러닝 기법을 활용하여 이를 예측하는 방법을 제시한다. 본 연구에 활용된 데이터와 프로그램 소스코드는 Kaggle 에 공개되어 있다.

• Monthly Korean Chicken
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• v.6 no.10 s.64
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• pp.2-7
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• 2000

정부, 닭고기 수출지원 검토 - ND, 마이코플라즈마 백신지원등 내년도 양계방역예산 크게 확대 - 한국가금학회 추계산학협동 심포지움 개최 - 농업 기자재 부가세 영세율 적용 3년간 연장 - 일본, 올해 닭고기 수요 1백 74만 7천톤으로 전망 - 브라질, 올해 상반기 닭고기 수출량 증가 - 북한에서 가축과 사료원료의 현황 - 닭고기 수입에 따른 피해액 연간 6백40억원 - 중국산 닭고기 수입 계속 늘어

• Journal of Energy Engineering
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• v.8
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• pp.74-85
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• 1999

우리 나라는 1970년대에 두 차례에 걸친 석유 파동을 겪으면서 에너지 정책의 중점 방향을 에너지 수요 관리와 안정적 에너지 공급 기반 조성 등으로 삼았다. 특히 에너지의 안정적 공급을 위하여 에너지원의 다원화, 수입선 다변화, 그리고 해외자원 개발 등이 추진되었다. 이러한 에너지 정책의 일환으로 천연가스의 도입이 적극 추진되어, 1983년 8월 한국가스공사가 설립되었으며, 1986년 10월 국내 최초로 액화천연가스(LNG)가 수입되고 다음달부터 공급되기 시작하였다. (중략)

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.1
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• pp.1-13
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• 2019

With commercial apps popular in EU, MaaS has been emerging around the globe as a new approach to worsening urban traffic problems. In contrast, it is still mainstay in Korea simply discussing the concept and necessities of MaaS, rather than seeking for real-world solutions for the commercialization. The purpose of this research is to analyze the demand-side i1mpacts of travel time and cost changes according to MaaS adoption, and to see its commercial feasibility in Korea. The 2010 KTDB traveler's nationwide OD data is used to estimate the level of fare discount for balancing the mode shift and fare revenue changes followed by MaaS implementation. The analysis results show that MaaS leads to the increase of public transport ridership as a result of the diminishing travel cost and time, and that the time saving works more positively for ridership increase. Also, the optimum level of fare discount is estimated 2.56% without damaging the revenue. This finding reveals that MaaS impact is superior to the other single-sided public transport inventive measures since it can affect both travel cost and time reduction at the same time.

• Economic and Environmental Geology
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• v.41 no.5
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• pp.509-516
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• 2008

For analyzing resources demand appropriately, corresponding demand data is essential. But it is hard to get the suitable data of each resource demand, because every resources has various type as refined and many kind of alloyed. That reason makes many analyses to employ the data of refined metals as the representative quantity. But those refined metals are factors for producing final goods so those in domestic market are not always meant for producing domestic end goods. Thus in this paper, the domestic demands of refined copper, lead and zinc are analyzed empirically with 'intensity of use' and foreign countries' income variable applied model for recovering the data availability.

• Environmental and Resource Economics Review
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• v.18 no.3
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• pp.495-521
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• 2009

This paper measures welfare losses from beef consumption reduction, which might be resulted from psychological anxiety about potential outbreak of BSE (commonly known as "bad cow dieses") risks after announcement of resuming US-beef imports in April of 2008. Unlike the previous literature of utilizing the contingent valuation method or experimental market approach, this study estimated quality-differentiated consumer demand functions using the information of self-reported beef consumption quantity, individually constructed price indices of beef, and subjective perception of BSE risks. The empirical results based on a survey sample of 360 residents in Jeon Ju city were consistent with the anticipation from economic theory, in terms of coefficients of own prices, substitute prices and income variables. The announcement of resuming US-beef imports did not make significant differences in the sign and sizes of the main economic variables. However, the subjective perception variable about BSE risks had negative significant impacts on beef demand functions after the announcement but not significant before the announcement. The welfare losses in a form of equivalent variation (EV) corresponding to the increases in concerns about BSE risks were measured to be about 30 thousand won per household.