• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.331-336
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• 2003

The advanced spent fuel conditioning process(ACP) was proposed to reduce considerably the overall volume and radioactivity for effective management of the PWR spent fuel in respects on safety and economy. The ACP is under research and development, and have scheduled to perform hot test for demonstration of the ACP after several years. For hot test, hot cell facility of ${\alpha}{\gamma}$ type possess conservative safety is required essentially. A existing hot cell of ${\beta}{\gamma}$ type will be refurbished to minimize construction expenditures of hot cell facility. In this study, the design requirements are established, and the process detail work flow was analysed for the optimum arrangement to ensure effective process operation in hot cell. And also, the basic and detail design of hot cell facility and process and safety analysis was peformed to secure conservative safety of hot cell facility and process.

• Journal of Digital Convergence
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• v.17 no.11
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• pp.207-213
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• 2019

The fuel-cut coast-down driving mode is activated when the acceleration pedal is released with transmission gear engaged, and it's a default function for electronic-controlled engine of vehicles. The fuel economy becomes better because fuel injection stops during fuel-cut driving mode. A fuel-cut detection method is suggested in the study and it's based on the speed, acceleration and road gradient data from GPS sensor. It detects fuel-cut driving mode by comparing calculated acceleration and realtime acceleration value. The one is estimated with driving resistance in the condition of fuel-cut driving and the other is from GPS sensor. The detection accuracy is about 80% when the method is verified with road driving data. The result is estimated with 9,600 data set of vehicle speed, acceleration, fuel consumption and road gradient from test driving on the road of 12km during 16 minutes, and the road slope is rather high. It's easy to detect fuel-cut without injector signal obtained by connecting wire. The detection error is from the fact that the variation range of speed, acceleration and road gradient data, used for road resistance force, is larger than the value of fuel consumption data.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.457-467
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• 2020

Increasing environmental concerns have prompted countries around the world to tighten regulations on greenhouse gases and fuel efficiency. Research is being done using advanced driver assistance systems to improve fuel economy and for the convenience of drivers. Research on systems such as adaptive cruise control (ACC), LKAS, and AEB is active. The purpose of ACC is to control the longitudinal speed and distance of the vehicle and minimize the driver's load, which is considered useful for accident prevention. From this point of view, research has used a mathematical method of safety evaluation as a function of distances and scenarios while considering domestic road environments. A vehicle is tested with a simulation in a proposed scenario. The purpose of the analysis is to verify the functional safety of ACC by comparing the theoretical calculations using theoretical equations, the relative distances in the simulation, and an actual vehicle test. These methods are expected to enable many companies to use scenarios, formulas, and simulations as safety verification methods in the development of ACC.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.7
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• pp.1-7
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• 2014

A variable displacement vane pump is possible to improve the fuel economy by varying the pump capacity with a vane mechanism according to the engine operating speed range and reducing its driving torque. In general the experimental evaluation of the vane pump for the transmission has been performed mainly not with the vehicle or dynamometer test rig but with component test rig due to the implementation and safety problems. In this paper, in order to evaluate the performance of the developed vane pump as well as the compatibility with other rotary and hydraulic components of the target transmission, the transmission dynamometer based test rig is implemented where the developed pump is built into it and then the variable pump capacity and effect of power reduction are investigated experimentally.

• Applied Chemistry for Engineering
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• v.31 no.3
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• pp.338-340
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• 2020

Sericite is used as a raw material for ceramics and paints, and recently it is widely used as adsorbents to remove heavy metals in wastewater. A new air filter containing sericite was developed using the principle of which components contained in the sericite react with moisture in the air to release oxygen. We tested whether the newly developed air filter actually improves fuel efficiency when mounted on a diesel vehicle. When the diesel vehicle used in the test was warmed up, the fuel efficiency increased by 10~17% compared to when an existing air filter was installed. However, the effect of the developed air filter on the amount of emissions (HC, CO, NOx) has not been investigated, and further research is required for the diesel vehicle emissions.

• Journal of the Korean Society of Industry Convergence
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• v.20 no.2
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• pp.105-113
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• 2017

Recently the direct injection diesel engine is the most efficient one available for road vehicles, so this fundamental advantage suggests the compression injection diesel engine are a wise choice for future development efforts. The compression ignition diesel engine, with its bigger compression ratios if compared to the SI engine, offers a higher thermodynamic efficiency, also additionally the diesel engine with its less pumping losses due to the throttled intake charge as in a SI engine has higher fuel economy. But the largest obstacle to the success of this engine is meeting emission standards for Nitric oxides and particulate matter while maintain fuel consumption advantage over currently available engines. Thus its use should be largely promoted, however, diesel engine emits more Nitric oxides and particulate matter than other competing one. There has been a trade-off between PM and NOx, so efforts to reduce NOx have increased PM and vice versa, but trap change this situation and better possibility emerge for treating NOx emission with engine related means, such as injection timing, equivalence ratio, charge composition, and engine speed. The common rail direct injection system is able to adjust the fuel injection timing in a compression ignition engine, so this electronically controlled injection system can reduce the formation of NOx gas without increase in soot. In this study it is designed and used the engine test bed which is installed with turbocharge and intercooler. In addition to equipped using CRDI by controlling injection timing with mapping modulator, it has been tested and analyzed the engine performance, combustion characteristics, and exhaust emission as operating parameters.

• Journal of the Korea Society of Computer and Information
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• v.27 no.9
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• pp.13-20
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• 2022

It's proposed and analyzed ML(Machine Learning) models to predict vehicle FC(Fuel Consumption) in real-time. The test driving was done for a car to measure vehicle speed, acceleration, road gradient and FC for training dataset. The various ML models were trained with feature data of speed, acceleration and road-gradient for target FC. There are two kind of ML models and one is regression type of linear regression and k-nearest neighbors regression and the other is classification type of k-nearest neighbors classifier, logistic regression, decision tree, random forest and gradient boosting in the study. The prediction accuracy is low in range of 0.5 ~ 0.6 for real-time FC and the classification type is more accurate than the regression ones. The prediction error for total FC has very low value of about 0.2 ~ 2.0% and regression models are more accurate than classification ones. It's for the coefficient of determination (R²) of accuracy score distributing predicted values along mean of targets as the coefficient decreases. Therefore regression models are good for total FC and classification ones are proper for real-time FC prediction.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.3
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• pp.93-101
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• 2018

FDM is one of the popular 3D printing technologies because of an inexpensive extrusion machine and multi-material printing. FDM can use thermoplastics such as ABS and PLA. The 3D-printed ABS parts fabricated by FDM are attractive in the automotive industry because of their weight. A 10% reduction in weight can increase the fuel economy by approximately 7%. To use 3D-printed ABS parts as automotive parts, we should evaluate the 3D-printed parts in terms of automotive reliability. In this study, 3D-printed ABS samples were evaluated using Ono's rotary bending fatigue test. We obtained an S-N curve for the 3D-printed ABS specimen from the finite-element analysis. The S-N curve can be useful in early-stage design decisions for 3D-printed ABS parts.

• Journal of Environmental Health Sciences
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• v.17 no.1
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• pp.13-19
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• 1991

Interest in the studies of diesel exhaust emission has been increasing by the expected increase in the use of diesel powered automobiles out of concideration of fuel economy. It was well known that diesel exhaust emission was mutagenic in the bioassay as Ames test. The authors tried to find out the cytogenetic effect of diesel exhaust emission by the operational condition of engine such as speed and load. For the investigation of those effects, 66 male mice of ICR strain were used. The benzene-ethanol extracts of diesel exhaust emission were injected intra peritoneum 25rng/kg and 50mg/kg respectively. To evaluate the cytogenetic effect, mouse bone marrow micronucleus test was carried out. The frequency of micronucleus was different among the various groups according to the operational conditions of engine. The frequency of micronucleus in idling group was the highest of all the groups the subgroup of 50mg/kg showed the rate of 1.30%, 25rng/kg subgroup 0.55%. And the group of 2000rpm with 50% load showed the lowest rate of micronucleus appearance as 0.20% and 0.15%. In general, the frequency of micronucleus was shown higher in propotion to load and was shown inversely proportional to speed.

• Journal of the Korea Safety Management & Science
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• v.10 no.2
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• pp.1-13
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• 2008

This Study is to analyze the characteristics of arson fire under fire dynamics to protect people and property from arson fire which has been radically increased with the development of the Korean economy. Assembly and merchandise purposes such as theater, retail, and exhibition has been performed as the arson fire study. The experiment for this study is based on the analysis of the characteristic for its own combustion process and smoke spread when arson fire occurs. This study presents the analysis through comparing the condition of setting fire using liquid fuel such as thinner on purpose to the condition of setting fire naturally depending on each occupancy.