• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.5
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• pp.59-65
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• 2014

Diesel engines have the superior combustion efficiency and fuel economy that they are widely used for industry, heavyduty vehicles, etc. However, its exhaust emissions have become the major concerns due to their environmental impacts. Moreover, the depletion of fossil fuels is the main issue. Therefore, it is important to look for alternative sources of energy. Bio-diesel is one of the ideal energy which has proved to be ecofriendly for more than fossil fuels. The experimental tests analysed the engine performance and emission characteristics of a diesel engine using diesel and biodiesel blended of BD25, BD45 and BD65, in order to study the use of clean fuel to meet the increasingly stringent emission regulations. The engine performance was examined by using engine dynamometer while an exhaust gas analyzer was used to examine the emission characteristics. The effect of biodiesel on engine performance were lower to diesel through comparing their HP and torque but fuel consumption was slightly increased because of biodiesel has lower heating value and higher density than diesel. However, due to the better lubricity, the brake thermal efficiency of biodiesel was higher than diesel. The emission characteristics were strongly affected by the blending ratio of diesel and biodiesel. The results showed that the smoke opacity, hydrocarbons (HC) and carbon monoxide (CO) emissions decreased while the nitrogen oxides (NOX) slightly increased.

• Journal of Soil and Groundwater Environment
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• v.20 no.6
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• pp.103-110
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• 2015

Nitro-aromatic Compounds (NACs) of explosives are structurally non-degradable materials that have an adverse effect to humans and ecosystems in case of emissions in natural due to the strong toxicity. In this study, batch test in the laboratory-scale has been conducted to find some process parameters of alkaline hydrolysis by considering the characteristics of NACs which are unstable in a base status and field application evaluation have been performed on the batch test results. Based on the experimental results of both laboratory and pilot-scale test, the optimum conditions of parameters for the alkaline hydrolysis of soils contaminated with explosives were pH 12.5, above the solid-liquid ratio 1 : 3, above the room temperature and 30 minute reaction time. In these four process parameters, the most important influencing factor was pH, and the condition of above pH 12.0 was necessary for high contaminated soils (more than 60 mg/kg). In the case of above pH 12.5, the efficiency of alkaline hydrolysis was very high regardless of the concentrations of contaminated soils. At pH 11.5, the removal efficiency of TNT was increased from 76.5% to 97.5% when the temperature in reactor was elevated from room temperature to 80℃. This result shows that it is possible to operate the alkaline hydrolysis at even pH 11.5 due to increased reaction rate depending on temperature adjustment. The results found in above experiments will be able to be used in alkaline hydrolysis for process improvement considering the economy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.163-170
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• 2016

Regulations for the exhaust gas of diesel vehicles are being strengthened every year. Recently, diesel emission regulations for HC, CO, NOx, and particulate matter (PM) have been subject to very strict standards. In the future, the regulation of PM is expected to become stricter. Accordingly, diesel particulate filters (DPFs) have been applied to most diesel vehicles for PM reduction. With increasing engine mileage, ash and soot from the engine exhaust gas accumulate inside the DPF. This accumulation can damage the DPF or degrade engine performance. Therefore, efficient cleaning of the DPF is critical for the maintenance of the engine. If the DPF is well managed through regular cleaning, it can improve the power and fuel economy of the engine and reduce maintenance costs. Therefore, this study was performed to develop a high-efficiency cleaning method for DPFs and an apparatus that can more effectively clean out the accumulated ash and soot.

• Journal of Biosystems Engineering
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• v.36 no.5
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• pp.303-313
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• 2011

This study was conducted to investigate the effects of axle weight distribution and inflation pressure of tire on the fuel economy of tractors as well as operational range of tractor engine in terms of engine speed and power when a 4WD tractor of 38.2 kW rated power at 2500 rpm is used for plowing and flooded-field rotavating in paddy fields. (1) Plowing operation required an average engine power of 9.6~13.5 kW which equals 25~35% of rated PTO power. Engine speed ranged from 1,320.4 to 1,737.4 rpm, work velocity from 3.4 to 4.8 km/h, and fuel consumption from 3.2 to 4.2 L/h, respectively. (2) Flooded-field rotavating required an average engine power of 11.5~18.5 kW which equals 30~48.4% of rated PTO power. Out of this 6.2~12.2 kW was used for PTO power. Engine speed ranged from 1,557 to 2,067 rpm, work velocity from 2.5~5.4 km/h and fuel consumption from 3.2~5.5 L/h, respectively. (3) Axle weight distribution, inflation pressure of tire and moisture content of soil did not affect significantly the specific volumetric fuel consumption but affected significantly the fuel consumption per unit area of operation. Fuel savings amounted to 65% in plowing operation and 20% in flooded-field rotavating when the axle weight distribution and inflation pressure of tire were optimally adjusted. (4) Optimal adjustment of axle weight distribution and inflation pressure of tire are expected to save fuel consumption by 10~65% per unit area of operation in plowing and 10~20% in flooded-field rotavating.

• The Journal of the Korea Contents Association
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• v.20 no.5
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• pp.595-608
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• 2020

In order to derive site selection planning factors in reforming aging industrial complex into urban high-tech industrial complex, this study selected key planning factors based on the problems of creating the urban high-tech industrial complex, innovation system theory, and external effect theory. And combined with Delphi research, the final planning factors were selected. As a result of the study, total 19 final factors were derived from 4 areas which includes efficiency planning factor utilizing the advantages of old industrial complex regeneration to maximize the efficiency of the project, corporate demand factor via increasing pre-sale rate and strengthening competitiveness, human resource planning factor by maintaining work force of the tenant to utilize and promote accumulated knowledge, and cooperative relationship building factor by enhancing connectivity with neighboring areas. These planning factors will help revitalizing the local economy through the resolution of regional conflicts caused by low distribution rates and development imbalances, which have emerged as problems in the creation of urban high-tech industrial complexes.

• International Commerce and Information Review
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• v.11 no.2
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• pp.173-201
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• 2009

As a result of overemphasizing the goods sector in trade structure, Korea does not meet properly the global trend which has the key role of 'trade in services' as the service economy have been expanded. Hereafter, it is easily forecasted that trade in services will be one of the main factors for Korea's competitiveness and engine of growth. Nevertheless, because Korea does not equip the concreteness of governance for trade in services, it is possible that the efficiency deterioration of trade volume, confusion of Korea's trade policy, conflict among trading countries, and discordance between the interested parties may be occurred. This paper analyzes the governance system of Korea for trade in services in order to enhance the competitiveness reflecting the importance of trade in services and to draw some strategies for remodeling the service governance system. It is expected to raise the efficiency of Korea's trade policy by constructing the systematic governance for trade in services, and to remove lots of latent risks during global transactions by improving the imbalance between manufacturing and service part for the development of trade in services in Korea. Analysis revealed itself the result that Korea is weak enough to can not identify the governance system about trade in services. Except 'Extent of Services' article of the Foreign Trade Act, Korea has not prepared the governance system for trade in services so that governance system have been scattered overly or decentralized. Problems about trade in services are not limited to enterprise's side, but extended to all the players including government agency whole, academic world and research institute. Therefore, the governance of trade in services should be strengthened and systematized by making the model law for trade in services(provisional name : Master Law for Trade in Services or Promotion Law for Trade in Services) by formatting type of fundamental law or separate legislation. If the bill legislation does not meet the conditions, the Foreign Trade Act should be totally reformed to Omnibus Trade Act concept including trade in services.

• Asia-Pacific Journal of Business
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• v.9 no.2
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• pp.75-103
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• 2018

The tax system in Korea is the so-called one-item-one-tax law which has separate tax law for each taxation according to tax law. The common and procedural aspects of these tax laws are the same or similar, but they are separately prescribed by the National Tax Basic Act and the Local Tax Act. These legal systems complicate the tax law and increase the cost of tax cooperation, resulting in tax inefficiency. In this study, the National Tax Act and the laws of the Local Tax Act are integrated and presented. It is proposed that the common provisions should be integrated into a single law and the unique matters should be defined in each of the National Tax Basic Act and Local Tax Basic Act, by comparing and analyzing the provisions of the National Tax Basic Act and the Local Tax Basic Act. The integration of the common elements of the National Tax Basic Act and the Local Tax Act is expected to improve tax efficiency by reducing tax complexity and tax cooperation costs. In addition, the National Tax Act and the Local Tax Act are expected to maintain the characteristics of the National Tax Basic Act and the Local Tax Act when they are specified in the National Tax Basic Act and the Local Tax Basic Act. This study is expected to be a research that can reduce tax inefficiency and help convenience of taxpayer and tax administration.

• Journal of the Society of Naval Architects of Korea
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• v.50 no.3
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• pp.145-152
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• 2013

Recently, with oil price jumping and environmental issues, Green ship is paid deep attention to by ship owner, operator, builder, class and government. Fuel efficiency and reduction of $CO_2$ emissions are expected to have a strong influence on the design and operation of merchant ships. Many ship owners and operators are seeking the more economic method by the best operating route and the application of reliable and effective energy saving devices. With the Energy Efficiency Design Index (EEDI) in 2013 attention will more than ever be focused at achieving maximum fuel economy in the hydrodynamic design of hull forms, their appendages and propellers. IMO requirements for $CO_2$ emission for ships will now be implemented for vessels ordered from 1st January 2013. So far, a lot of new idea and patents have been proposed, tested, claimed and applied for various kinds of ship type. This paper shows numerical and experimental work related to a study on a energy saving devices particularly for fuller ship such as merchant vessel of Tanker and Bulker. From the bare hull wake measurements, typical upper/lower asymmetry of hull wake at the propeller disk was found. The pre-swirl duct have been designed and reviewed to recover the loss of propeller running in that condition. The general function of the pre-swirl duct was set to work against this asymmetry of wake and generate pre-swirled flow into the propeller against the propeller rotating direction.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.11
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• pp.963-970
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• 2016

This research deals with design and performance validation of eco-pedals that generate tactile pedal force to guide fuel saving driving behavior. For eco-pedal control logic, allowable fuel consumption at given driving speed is calculated based on pre-defined "allowable acceleration", and if the actual fuel consumption exceeds the allowable fuel consumption, then pedal force is activated. Pedal force should be recognizable to driver while not causing unpleasantness, and should not interfere with normal operation of pedal. Reaction forces that increase pedal stiffness abruptly, such as step and ramp shape, turn out to be not suitable due to pedal overshoot after release of reaction force. With this regards, vibration type reaction force is adopted, and its optimal frequency, magnitude and duration is determined through subjective evaluation with consideration to effect to fuel efficiency. Though highway and city driving test, it is demonstrated that fuel efficiency increase of 13% for highway and 15% for city is achieved.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.433-440
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• 2013

The Ministry of Land, Infrastructure and Transport was developed the Construction CALS system for improvement of the construction economy. Construction CALS system is consist by Construction Portal System, Construction Management System, Construction Authorization and Permission System, Compensation Management System, Facility Maintenance Management System and has utilized at construction site of more than 900. Ministry of Land, Infrastructure and Transport and related researcher was proposed method of various function improvements for usability of the system. However, the proposed method was expanded the problems like increase of system management cost and development cost with decrease of data process rate. The problem was increases because has added of only service function without modify of software structure to the system on each different platform base. One of the methods for solving problems is to apply the e-Government framework and then integrated the different platform. The purpose of this paper is analyse of the applicability and efficiency of e-Government framework to the construction CALS system. For that was analyzed the e-Government standard framework and the developments case. And then was verified about the adaption possibility and efficiency by use the Function Point tool.