• Korean Journal of Agricultural Science
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• v.47 no.1
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• pp.29-41
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• 2020

Biodiesel is a clean energy resource that can replace diesel as fuel, which can be used without any structural changes to the engine. Vegetable oil accounts for 95 percent of the raw materials used to produce biodiesel. Thus, many problems can arise, such as rising prices of food resources and an imbalance between supply and demand. Most of the previous studies using waste cooking oil used waste cooking oil from a single material. However, the waste cooking oil that is actually collected is a mixture of various types of waste cooking oil. Therefore, in this study, biodiesel produced with mixed waste cooking oil was supplied to an agricultural single-cylinder diesel engine to assess its potential as an alternative fuel. Based on the results, the brake specific fuel consumption (BSFC) increased compared to diesel, and the axis power decreased to between 70 and 99% compared to the diesel. For emissions, NO_x and CO₂ were increased, but CO and HC were decreased by up to 1 to 7% and 16 to 48%, respectively, compared to diesel. The emission characteristics of the mixed waste cooking oil biodiesel used in this study were shown to be similar to those of conventional vegetable biodiesel, confirming its potential as a fuel for mixed waste cooking oil biodiesel.

• Korean System Dynamics Review
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• v.5 no.1
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• pp.49-71
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• 2004

Demand-side Management can be defined as'any utility activity aimed at modifying customers' use of energy to produce desired changes in the utility's load shape'. Customers benefit by being able to control energy costs and improve quality of life and become more productive. Utilities benefit from DSM's value as a resource that enhances asset utilization and reduces both fuel costs and environmental emissions. The scope of DSM includes load management through rate schedules and conservation by improving energy effciency and using electricity consumption effectively. This paper study the DSM resource evaluation and customer behavior analysis todesign the DSM Program plan in response to customer needs. We develop basic system dynamics model to analysis the customer behavior based on a survey research. The DSM Program participants in the Hi- efficiency Inverter, Electric motor and efficient lighting applicancies operating by Conservation program 2002 become the survey objects. DSM resource evaluation evaluate firstt the distribution potentialities of each machine and then forecast the degree of diffusion. We apply the system dynamic approach to simulate the dynamic DSM market situation at the domestic beginning. This model will give the energy Planner the opportunity to create different scenarios for DSM program planning. Also it will lead to increased understanding of the dynamic DSM market

• Journal of Navigation and Port Research
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• v.38 no.6
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• pp.567-575
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• 2014

In recent times, an obvious strategy in liner shipping markets that has come to the fore is slow steaming. Nowadays, most liner shipping companies have decelerated the voyage speed to 15-18 knots on major routes, and some leading liner shipping companies have a plan to reduce it to below 15 knots. Slow steaming is helpful in reducing the operating cost and the amount of greenhouse-gas emissions on a single vessel with lower fuel consumption. However, it also creates various negative effects such as the opportunity cost, additional fixed costs and an in-transit inventory cost on a loop. Hence, the net operating cost on a loop is changing dynamically due to the changes of voyage speed based on various slow steaming effects. The aim of this study is to analyze the slow steaming effects in the liner shipping, and to find the best voyage speed that minimizes the operating cost on a loop. Moreover, this study suggests the recommendable strategy for liner shipping companies. To achieve the aim of this study, a simulation model has been designed using System Dynamics.

• Environmental Engineering Research
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• v.17 no.1
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• pp.27-34
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• 2012

This paper deals with the evaluation of environmental impact of rail and road transport in South Korea. A framework of energy input-output analysis is employed to estimate the total energy consumption and $CO_2$ emission in acquiring and using a life cycle of passenger and freight transport activity. The reliability of $CO_2$ emission based on uncertainty values is assessed by means of a Monte Carlo simulation. The results show that on a passenger-kilometers basis, passenger roads have life cycle emissions about 1.5 times those of rail, while that ratio is ten times greater when the scope of evaluation regards the tailpipe. In the case of freight transport, on a million ton-kilometers basis, the value for road mode is estimated to be about three times compared to those of rail mode. The results also show that the main contribution of $CO_2$ emission for road transport is the operation stage, accounting for 70%; however, the main contribution for rail transport is the construction and supply chain stage, accounting for over 50% emission.

• Journal of Energy Engineering
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• v.25 no.3
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• pp.149-156
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• 2016

This paper surveyed and analyzed cases of DB development overseas to set the range of DB to be developed for analyzing energy-saving policies in the domestic transportation sector. The foregoing prerequisites were used to establish system for classification in the broad scale under which system for classification in detail indicators that suit one in the broader indicators was set based on analysis of domestic / overseas cases to determine DB development range in the transportation sector required to analysis domestic energy-saving policies. Accordingly, six items subject to the broadest classification were determined, i.e. energy consumption, energy basic unit, emissions of greenhouse gas, economic indicators, transportation volume / transportation records and basic automobile data. Large classification and sub-items determined by surveying expert opinions were set and proposed as DB classification indicators.

• Journal of Environmental Policy
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• v.6 no.2
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• pp.27-45
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• 2007

This paper presents a method for developing the performance assessment of energy conservation and efficiency based on baseline and target adjustment approach. Energy consumption is related with output level and production structure. This paper suggests improvement for target establishment and performance assessment with regard to real output level in target year. Numerical illustrations of baseline and target adjustment method are shown different compared with the general assessment results. This study will contribute to applying the conformity assessment and Greenhouse Gas Emissions verification system.

• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.295-296
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• 2015

We presented the methods calculating the reduction efficiency of nitrogen oxide for the low $NO_x$ burner as the pollution prevention facilities. The standard $NO_x$ concentration was used on the emission factor of LNG, $3.7g/m^3$. The $NO_x$ reduction efficiency based on the $NO_x$ concentration was presented and the relationships between the $NO_x$ concentration and the emission factor or the specific heat emission factor were derived. These results could be accurately reflected on calculating the amount of the nitrogen oxide emissions. In addition, according to the arrangement of the low $NO_x$ burners the methods of applying their $NO_x$ reduction efficiency were proposed. The $NO_x$ reduction efficiency for the facilities consisting of the low $NO_x$ burners and the non-low $NO_x$ burners could be estimated with information about the reduction efficiency of each low $NO_x$ burners, the fuel consumption rate, and the heating value of fuel.

• International Journal of Advanced Culture Technology
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• v.7 no.2
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• pp.144-150
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• 2019

Recently, an increasing number of urban farmers are growing fresh vegetables and fruits themselves using urban garden or weekend farms. In other words, this is called urban agriculture. After the Industrial Revolution in the 18th century, the agricultural society changed from an agricultural society to an industrial society, and the population began to flock to the cities. With the continued increase of urban population, countries with abundant capital were able to control the distribution structure of food supplies and trade agreements among countries. Since energy consumption and carbon dioxide emissions caused by agricultural product movements have emerged as the main culprits of global warming, and our table is threatened by safety due to food supply that has no genetic modification or knowledge of the cultivation process, urban agriculture is already taking hold in the West. In other words, as agriculture met cities, its role grew. Each region actively conducts agricultural activities for raising poultry as well as growing vegetables and fruits by using flower beds of detached houses in the city center, rooftops of high and low buildings, or school playgrounds and small tributaries of land. The purpose of this study is to analyze and understand the significance and type of urban agriculture and to examine the cases of domestic and foreign urban agriculture based on this and to seek the developing direction of urban agriculture, which is gradually increasing. Tired of growing competition and rapid change, urbanites are seeking health and relaxation and are planning to present development measures for urban farming and conduct follow-up research to ensure safe food.

• Journal of Climate Change Research
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• v.5 no.3
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• pp.219-230
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• 2014

In this study, greenhouse gas emission of magnesium industry was estimated and the reduction potential of the greenhouse gas emission was evaluated with reduction technologies. Default value of IPCC guideline was used to calculate the greenhouse gas emission and $SF_6$ alternatives were considered in reduction potential. Import of magnesium ingot was 22,806 ton in 2013, which will be expected to increase to 81,700 ton with 20% rate in 2020. Magnesium ingot was consumed to produce magnesium alloy in diecasting process. Recently, commercial production of crown magnesium and magensium plate began. Based on ingot consumption, $CO_2$ emission of domestic magnesium industry was estimated to 504,000 ton, which is about 0.79% of domestic industrial emissions. Reduction potential of diecasting process was estimated to 489,320 ton by changing SF6 to alternative gases such as HFC-134a, Novec-612. Emission factor of Tier 3 level should be developed to enhance the accuracy of greeenhouse gas emission of magnesium industry.

• Journal of the Korean Wood Science and Technology
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• v.44 no.3
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• pp.449-456
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• 2016

This study was aimed to quantify the amount of carbon dioxide emissions and to suggest suitable plans which consider the carbon emission reduction in the manufacturing process of the domestic structural glued laminated timber. Field investigation on two glued laminated timber manufacturers was conducted to find out material flow input values such as raw materials, transportation, manufacturing process, and energy consumption during manufacturing process. Based on the collected data and the relevant literatures about life cycle inventory (LCI), the amount of carbon dioxide emission per unit volume was quantified. Results show that the carbon dioxide emissions for sawing, drying and laminating process are 31.0, 109.0, 94.2 kg $CO_2eq./m^3$, respectively. These results show 13% lesser amount of total carbon dioxide emissions compared with the imported glued laminated timber in Korea. Furthermore, it was decreased about 37% when the fossil fuel would be replaced with biomass fuel in drying process. Findings from this study is effectively used as the basic data on the life cycle assessment of wooden building.