• 한국토양비료학회지
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• 제9권3호
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• pp.117-132
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• 1976

Fertilizer has been played greately on the agricultural development as well as food production and agriculture has also promoted the development of fertilizer industry. There were, however, many difficulties between supply and demand of fertilizer throughout the decade. In this regard, this paper is involved with present situation and prospect of commercial fertilizers, in view of domestic and international scheme on resources, production, and demand within the limited information. Brief history of commercial fertilizer in Korea has outlined for the introduction and fertilizer consumption per unit area also discussed.

• 에너지공학
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• 제1권1호
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• pp.102-110
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• 1992

The determination of production level of the domestic anthracite coal is an important issue in the national energy strategy. It is also closely related to the energy mix scenarios in the future. The objective of the paper is to discuss and analyze the options of expanding anthracite coal demand in the utility sector. The observed options are including; (1) New pulverized system of the 200 and 500 MW level, (2) Atmospheric Fluidized Bed Combustion (AFBC), and (3) Pressurized Fluidized Bed Combustion (PFBC). Special emphasis is placed on the considerations in estimating the effects on the electric system costs and government subsidies when the options are introduced in the utility sector.

• 항공우주시스템공학회지
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• 제8권3호
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• pp.34-40
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• 2014

Since the global economic crisis in year 2008, the world civil helicopter market has been growing recently. According to the market outlook in the next decade, the demand of civil helicopter will be driven by the demand of Private & Corporate, Oil & Gas, Off-shore and EMS(Emergency Medical Service) usages. On the other side, the demand of military market will be driven by the modification and upgrading for life extension or performance enhancement than the new helicopter development for replacing old models. To summarize these situations, the demand of MRO(Maintenance, Repair & Overhaul) market has also been on the rise because of the demand due to above several usages in civil side and the life-extension in military side. Through the MRO market analysis for characteristics, developmental trends and a supply chain, this paper describes that the potential of MRO business is considerably large as a propulsive power of domestic helicopter industry. And also, it proposes the construction direction of MRO network because the domestic industry must make the developmental awareness and reliability a stepping-stone towards own helicopter.

• 대한교통학회지
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• 제26권1호
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• pp.51-63
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• 2008

제주-내륙 간 국내선 항공여객수요는 여가통행의 대표적인 시계열 특성인 1년을 주기로 증감을 반복하는 전형적인 계절변동 패턴을 보인다. 본 연구는 10년(1996${\sim}$2005) 동안의 제주-내륙 간 월별 시계열 총량자료를 이용하여 단순시계열모형과 부분조정모형 및 이들 모형별 탄력성(소득, 운임)을 추정하였다. 탄력성 추정결과 단순시계열모형의 경우 소득탄력성은 탄력적(1.55), 운임탄력성은 비탄력적(-0.49${\sim}$-0.59)으로 추정되었다. 부분조정모형의 경우 소득탄력성은 단기에는 비탄력적(0.51), 장기에는 탄력적(1.88)으로 추정되었으며, 운임탄력성은 장 단기 모두 비탄력적으로 추정되었으나, 단기(성수기:-0.13, 비수기:-0.20)보다는 장기(성수기:-0.48, 비수기:-0.72)가 보다 더 탄력적으로 추정되었다.

• 자원ㆍ환경경제연구
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• 제31권1호
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• pp.85-112
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• 2022

우리나라의 미세먼지 및 초미세먼지 농도에 대하여 전국 및 지역별 패널 분위회귀분석을 진행하여, 국내 및 중국 요인의 영향력을 분석하였다. 2015년 5월 1일부터 2020년 12월 31일까지 일별 분석을 진행하였으며, 국내 요인으로는 전력수요 및 교통량을, 중국 측 요인으로는 베이징 등 3개 도시의 미세먼지 및 초미세먼지 농도와 서풍의 교차항을 이용하여 패널 분석을 진행하였다. 국내 미세먼지 농도가 높고 낮을 때 국내 요인의 영향력이 다르게 나타났다. 미세먼지 농도가 낮을 때, 전국분석에서 국내 화력발전의 대리변수인 전력수요량은 초미세먼지에 양(+)의 영향력을 미쳤다. 지역별 분석결과, 수도권 및 충청도 지역에서만 전력수요량이 미세먼지 및 초미세먼지에 유의한 영향을 미치는 것으로 나타났다. 반면, 미세먼지 농도가 높을 때, 전력수요량은 미세먼지 및 초미세먼지 농도를 모두 유의하게 상승시키는 것으로 나타났다. 초미세먼지의 경우 그 추정치가 더 높게 나타났다. 반면, 중국 요인의 경우 미세먼지 및 초미세먼지 농도와 관계없이 우리나라에 항시 양(+)의 영향을 미침을 확인하였다. 향후 국내 초미세먼지 문제를 해결하기 위해서는 4계절 항시 국제적 협력이 필요하며, 국내 화력발전으로 인한 초미세먼지 발생분에 대한 감축이 현재보다 강화되어야 함을 확인할 수 있다.

• 수산경영론집
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• 제44권3호
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• pp.47-60
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• 2013

A study on the seamen's demand - supply has been focused on early 1990s, and never studied yet since 2007. Because previous studies related to the seamen are very different in conditions the environments around the fishery recently. It is serious problem that the number of domestic semen are decreasing continually. To depend on foreign seamen because of lacking of domestic seamen should be linked closely with the fishing industry environment in our country. Therefore, this study is limited to domestic seamen. Lacking recent domestic seamen, it is the most likely to rise imbalance between demand - supply in the future. Through medium and long term its analysis based on data, we are willing to discover various political subjects for seamen's welfare, the training of manpower, education, etc. To solve these issues, it can be made institutional changes as follows ; First, it is necessary policy-making related the deteriorating employment situation based on its analysis of medium and long term for seamen. Second, it is necessary to overcome a dual system for its management for seamen. Third, it is necessary to improve problems of statistics data for fishery and build a statistical system for seamen. Also, it will be improved a insurance system under 5 ton and strengthen the function for Korean seamen welfare and employment center and must be urgently countermeasures for the minimal unemployment rate through a content development and management of home page. Finally, it will be supplied reliably seamen to improve a practice system for apprentices according to the international regulations(STCW-F) for fishery students.

• Journal of Biosystems Engineering
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• 제38권4호
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• pp.248-254
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• 2013

Purpose: This study was performed in order to obtain basic data for policy development and R&D to sharpen competitiveness in domestic agricultural machinery industry by analyzing the recent status of demand and supply for tractor, rice transplanter(riding type), and combine. Methods: Basic data from 199,275 units of tractor, rice transplanter (riding type), and combine was offered by the National Agricultural Cooperative Federation and Korea Agricultural Machinery Industry Cooperative. Those agricultural machines were supplied by the government's loan support from 2003 to 2012. Results: Recent supply of tractor is only 13,000 units or so per annum, thereby being stagnated. Rice transplanter and combine in 2012 corresponded to 3,810 units and 2,490 units, respectively. The domestic market share of the imported agricultural machinery accounted for 60.0% in tractor, 99.5% in saddle rice transplanter, and 80.9% in combine, thereby having been sharply increased 33.1%p, 42.0%p and 53.6%p compared to the ones in 2003. Life spans of tractor, combine and saddle rice transplanter are 3.7, 3.7 and 4.2 years, respectively. Among the discontinued models, the one less than 300 units supplied was occupied up to 70~85%. Conclusions: The domestic demand and the export expansion are needed through developing a model of agricultural machinery of having competitiveness to domestically activate agricultural machinery industry.

• 한국수소및신에너지학회논문집
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• 제17권1호
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• pp.90-97
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• 2006

Hydrogen is used as a chemical feedstock in several important industrial processes, including oil refineries and petro-chemical production. But, nowadays hydrogen is focused as energy carrier on the rising of problems such as exhaustion of fossil fuel and environmental pollution. Thermochemical hydrogen production by nuclear energy has potential to efficiently produce large quantities of hydrogen without producing greenhouse gases, and research of nuclear hydrogen, therefore, has been worked with goal to demonstrate commercial production in 2020. The oil refineries and petro-chemical plant are very large, centralized producers and users of industrial hydrogen, and high-potential early market for hydrogen produced by nuclear energy. Therefore, it is essential to investigate and analyze for state of domestic hydrogen market focused on industrial users. Hydrogen market of petro-chemical industry as demand site was investigated and worked for demand forecast of hydrogen in 2020. Also we suggested possible supply plans of nuclear hydrogen considered regional characteristics and then it can be provided basis for determination of optimal capacity of nuclear hydrogen plant in 2020.

• 대한안전경영과학회지
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• 제9권1호
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• pp.175-186
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• 2007

The employment permit system for foreigners, which stresses introduction of foreign work force in a legal manner rather than in the position of being trainees, is anticipated to efficiently improve introduction and the overall management system of foreign work force and related difficulties such as illegal alien problems, absurdity on sending laborers overseas. In this paper, a prospective model of supply and demand of work force has been developed basing on various categories of industries and patterns about nationally practical foreign employees to look over efficient supply and demand of work force suiting employment of foreigner among foreign work force policies. To propose the prospective model, we have derived industry- and pattern-related matrixes of foreign laborers basing on Inter-Industry Analysis Method put forth by Professor Leontiyef in 1930, and through the derived matrix assessed repercussions concerning overall domestic industries and foreigner types and decided yearly weight; the capacity of supply and demand of foreign laborers can be compared through proposed statistical estimation and government estimation by combining the determined weight with yearly incomes of foreign laborers. This paper has thoroughly considered the particularity of our employment permit system for foreigners and applied the Weibull distribution and incorporated the dependence of foreign laborers during the limited period of 3 years to the industry relation analysis, ultimately proposing an efficient supply and demand method about domestic foreign work force.

• 대한교통학회지
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• 제35권2호
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• pp.91-104
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• 2017

본 연구에서는 통합모형인 GCAM을 활용한 국내수송부문을 모델링에 대해 논의한다. GCAM은 IPCC 5차 보고서 평가에도 활용된, 국제적으로 널리 쓰이는 모형이다. 그럼에도 불구하고 이를 국내수송부문에 그대로 적용하는 데 상당한 문제가 있다. 첫째, GCAM의 기준년도(2010년) 수송 서비스수요가 국가통계와 일치하지 않다는 점. 둘째, 수송부문 시뮬레이션 결과가 관련 부문별 서비스수요의 과거추이를 제대로 반영하고 못하고 있다는 점이다. GCAM을 활용한 국내 수송부문 모델링에서 가장 중요하게 영향을 미치는 수송서비스수요 항등식을 상세히 점검함으로써, 기준년도의 서비스수요를 국가통계와 일치시키도록 노력하였다. 또 GCAM의 시뮬레이션 결과가 과거 통계추이를 제대로 반영할 수 있도록 기존모형을 점검, 수정하였다. 점검 및 수정결과, 기존 GCAM의 시뮬레이션 결과와 어떤 부분에서 문제가 있는지, 또 수송부문별 과거 서비스 수요의 추이가 어떻게 제대로 반영되고 있는지를 상세히 보고하였다. 본 연구는 향후 수송부문의 정책, 기술평가 및 온실가스저감 대책 마련 등을 위한 시나리오 분석의 기본분석도구로 유용하게 쓰일 수 있을 것으로 보인다.