• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.5
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• pp.637-645
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• 2019

Global warming and a new energy policy request the energy saving and pollutant emission control in municipal level. Previous studies focus on transportation in the Seoul metropolitan area which can easily meet the policy goal by reducing it. This study expands the area of urban energy planning to the industries and land use which takes up most of energy use of the city. We empirically study the Busan metropolitan area's 5 years natural gas and electricity consumption data by the industries and land use. Results show that energy usage significantly depends on not only population but also urbanizing intensity and industrial category. This paper address that the policy maker need to pay attention on energy usage pattern of each sectors during the planning.

• Journal of the Economic Geographical Society of Korea
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• v.25 no.2
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• pp.203-218
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• 2022

The global value chain, as a major feature of the contemporary global economic system, has been mainly led by developed countries. Whereas developing countries have taken the relatively low value-added activities and this made geographical imbalances in value distribution. This imbalance in value distribution, however, began to gradually alleviated. Related to this phenomenon, the purpose of this research is to analyze the factors affecting factors. Focused on the method of upgrading the industry in the global value chain, the impact on the acquisition of value-added in developing countries was analyzed among the various factors to achieve the research purpose. Panel analysis was conducted on all industries, food and tobacco industries, textile and clothing industries, computer and electornics industries, and automobile industries of the OECD Value-Added Trade Data (TiVA). As a result of the analysis, it was confirmed that in all industries, value-added acquisition in developing countries was improved by increased total production, high value-added product production and participation in early stage. The analysis results by detailed industry showed slightly different patterns depending on the characteristics of each industry.

• Environmental and Resource Economics Review
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• v.23 no.3
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• pp.515-551
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• 2014

Recently, there has been a debate as to whether bioethanol should replace some portion of gasoline for fuels in South Korea, as energy security as well as climate change issues are rising as a significant national agenda. However, a considerable amount of subsidy will be required to compensate for the higher price of bioethanol-blended gasoline. In this context, government subsidy will obtain justification only when the positive social gains from consuming bioethanol for fuels can exceed the negative social costs. Through a nation-wide choice experimental survey, we examine if South Koreans have a positive value as well as non-linear preferences on substituting bioethanol for gasoline. The results reveal that the willingness to pay for purely domestic bioethanol-blended gasoline within 10% is about 52 KRW; Koreans have concave preferences on the blending ratio of bioethanol to gasoline. The turning point of the blending ratio of bioethanol was 6.5%. Also, we found inverse U-shaped curve between income and bioethanol choice probability and the turning point of the income was calculated as 250~299million KRW. Politically conservative propensity advocates uses of bioethanol blended gasoline, but awareness on bioethanol or more weights on environmental conservation have significantly negative effects on the choice of bioethanol. However, the design of the survey questionnaire is incompatible with the RFS of Korea and assumes orthogonality among the following four interrelated attributes: (i) domestic or offshore procurement of feedstocks in the case of domestic production, (ii) domestic production or import of bioethanol, (iii) the blending ratios, and (iv) the retail price increases. In addition, the results of model estimation and of model selection test are not definite. Hence, the results in this study should not be directly applied to the design of the specifics of the Korean RFS. Hence, the results in this study require cautions in applying to the design of the Korean RFS policy.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.81-81
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• 2013

반도체, LCD, MEMs 등 미세 전자소자의 제작과 깊은 관련이 있는 IT 산업은 자동차 산업과 함께 세계 경제를 이끌고 있는 핵심 산업이며, 그 발전 가능성이 크다고 할 수 있다. 이 중 반도체, LCD 공정 기술에 관해서 대한민국은 세계를 선도하여 시장을 이끌어 나가고 있는 실정이다. 이들의 공정기술은 주로 높은 수율(yield)을 기반으로 한 대량 생산 기술에 초점이 맞추어져 있기 때문에, 현재와 같은 첨예한 가격 경쟁력이 요구되는 시대에서 공정 기술 개발을 통해 수율을 최대한으로 이끌어 내는 것이 현재 반도체를 비롯한 미세소자 산업이 직면하고 있는 하나의 중대한 과제라 할 수 있다. 특히 반도체공정에 있어 발전을 거듭하여 현재 20 nm 수준의 선폭을 갖는 소자들의 양산이 계획 있는데 이와 같은 나노미터급 선폭을 갖는 소자 양산과 관련된 CD (critical dimension)의 감소는 공차의 감소를 유발시키고 있으며, 패널의 양산에 있어서 생산 효율 증가를 위한 기판 크기의 대형화가 이루어지고 있다. 또한, 소자의 집적도를 높이기 위하여 높은 종횡비(aspect ratio)를 요구하는 공정이 일반화됨에 따라 단일 웨이퍼 내에서의 공정의 균일도(With in wafer uniformity, WIWU) 및 공정이 진행되는 시간에 따른 균일도(Wafer to wafer uniformity)의 변화 양상에 대한 파악을 통한 공정 진단에 대한 요구가 급증하고 있는 현실이다. 반도체 및 LCD 공정에 있어서 공정 균일도의 감시 및 향상을 위하여 박막, 증착, 식각의 주요 공정에 널리 사용되고 있는 플라즈마의 균일도(uniformity)를 파악하고 실시간으로 감시하는 것이 반드시 필요하며, 플라즈마의 균일도를 파악한다는 것은 플라즈마의 기판 상의 공간적 분포(radial direction)를 확인하여 보는 것을 의미한다. 현재까지 플라즈마의 공간적 분포를 진단하는 대표적인 방법으로는 랭뮤어 탐침(Langmuir Probe), 레이저 유도 형광법(Laser Induced Fluorescence, LIF) 그리고 광섬유를 이용한 발광분광법(Optical Emission Spectroscopy, OES)등이 있으나 랭뮤어 탐침은 플라즈마 본연의 상태에서 섭동(pertubation) 현상에 의한 교란, 이온에너지 측정의 한계로 인하여 공정의 실시간 감시에 적합하지 않으며, 레이저 유도 형광법은 측정 물질의 제한성 때문에 플라즈마 내부에 존재하는 다양한 종의 거동을 살필 수 없다는 단점 및 장치의 설치와 정렬(alignment)이 상대적으로 어려워 산업 현장에서 사용하기에 한계가 있다. 본 연구에서는 최소 50 cm에서 최대 400 cm까지 플라즈마 내 측정 거리에서 최대 20 mm 공간 분해가 가능한 광 수광 시스템 및 플라즈마 공정에서의 라디칼의 상태 변화를 분광학적 비접촉 방법으로 계측할 수 있는 발광 분광 분석기를 접목하여 플라즈마 챔버 내의 라디칼 공간 분포를 계측할 수 있는 진단 센서를 고안하고 이를 실 공정에 적용하여 보았다. 플라즈마 증착 및 식각 공정에서 형성된 박막의 두께 및 식각률과 공간 분해발광 분석법을 통하여 계측된 결과와의 매우 높은 상관관계를 확인하였다.

• The Journal of the Korea Contents Association
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• v.22 no.3
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• pp.354-360
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• 2022

Metabolic disease is a disease with a prevalence of 26% in Korean, and has three of the five states of abdominal obesity, hypertension, hunger glycemic disorder, high neutral fat, and low HDL cholesterol at the same time. This paper links the consumer panel data of the Rural Development Agency(RDA) and the medical care data of the National Health Insurance Service(NHIS) to generate a classification model that can be divided into a metabolic disease group and a control group through food consumption characteristics, and attempts to compare the differences. Many existing domestic and foreign studies related to metabolic diseases and food consumption characteristics are disease correlation studies of specific food groups and specific ingredients, and this paper is logistic considering all food groups included in the general diet. We created a classification model using regression, a decision tree-based classification model, and a classification model using XGBoost. Of the three models, the high-precision model is the XGBoost classification model, but the accuracy was not high at less than 0.7. As a future study, it is necessary to extend the observation period for food consumption in the patient group to more than 5 years and to study the metabolic disease classification model after converting the food consumed into nutritional characteristics.