• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.593-594
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• 2010

• Proceedings of the Korea Society of Design Studies Conference
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• 2005.05a
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• pp.56-57
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• 2005

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.5
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• pp.54-59
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• 2011

Reliable starting capability of a gas turbine engine calls the engine industry's attention recently. So far the gas turbine engine performance researches have focused on the range between idle to Max rpm, but recent attention on the starting has brought interests in the range of "Sub-dile". As component characteristic maps are essential for the starting research, various kinds of studies have been doing and proposing ways to expand the existing maps toward sub-idle range. In this paper, previous studies were discussed and a new method suggested and validated.

• Journal of ILASS-Korea
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• v.23 no.3
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• pp.128-135
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• 2018

In this study, the following conclusions could be obtained from the analysis of emissions contribution rates and features for contaminated emissions by 13,456 gasoline vehicles passed in the vehicle load test (ASM-idle) under the inspection year 2013 to 2017. It was confirmed that the contamination of the CO, HC, NOx by the displacement is reduced on over 3L engine. As a result of comparing the exhaust gas in the low speed idle mode and the AS2525 mode, the exhaust gas in the low speed idle mode was measured high. It is estimated that if ISG function is applied, emissions from idle condition will be reduced. NOx emissions were reduced when the engine power was above 200HP. It has been confirmed that the amount of exhaust emissions are significantly reduced for vehicles manufactured after 2004. As a result of analyzing the exhaust gas according to the season, it is judged that there is a correlation between HC and NOx according to the ambient temperature. The concentration of exhaust emission in vehicles with high accumulated distance increases, which is considered to be the result of aging of the vehicle.

• Korean Institute of Interior Design Journal
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• v.20 no.3
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• pp.59-68
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• 2011

As society alters and building ages, many industrial facilities lost their function and abandoned in central city areas, and sometimes creating many problems. However, many European countries successfully transformed those urban decay to vivid cultural hub. The purpose of this study was to analyze a concept and methods of converting idle industrial facilities to successful cultural spaces. A case study of Tate Modern, Baltic Center for Contemporary Art, and Ruhr Museum was conducted using literature review, site visit, and interview methods. Findings indicated that converting historically significant idle industrial facilities to cultural center had not only reused abandoned site but also helped regenerating adjacent urban areas. This article demonstrates the key factors of successful conversion strategies as convenience, participation, placeness, historicity, and accessibly; and thus an effort to actively enhance the strategic factors were demanded in future conversion projects. A continuous studies on exploring extensive cases in various perspectives are required for further generalization in future studies.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.1
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• pp.71-76
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• 2014

This Research focuses on how to maximize fuel economy improvement of I.S.G. while keeping 12V system. With 12V system the maximum gain of fuel economy with I.S.G. is known to be about 3~5% in FTP-75 mode because engine stop is only conducted in standstill idle. But in this study deceleration engine stop (engine speed is zero) has been tried additionally and the optimum condition for deceleration engine stop was found to maximize fuel economy improvement in practical point of view, the result of which is about 8.8% in FTP-75.

• Journal of Satellite, Information and Communications
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• v.11 no.4
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• pp.52-57
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• 2016

The backscatter signals are very weak so they can be easily interfered by signal interferences and channels. In this paper, we propose a two-level classification algorithm for backscatter communications which chooses the idle frequency channel based on cognitive radio systems. The two-level classification algorithm provides an optimal idle frequency channel by obtaining informations about idle frequencies, fading of the channels, and the channels' usage state by primary users. Our simulation results show the improvement of BER and received power performance in backscatter communications by using the proposed algorithm, and the improvement of the algorithm's performance in backscatter communications.

• KIEAE Journal
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• v.16 no.1
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• pp.103-110
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• 2016

Purpose: This study suggests the multi-purposed emotional space that is one of the alternatives to reuse idle spaces in the city. Because human who is living in modern society begins pursue new contents and leisurely life all the time and live toward the period of high emotion with personal characteristics, architectural industry also need to change its planning and design to satisfy contemporary man and to adjust rapid social mobility. Method: For this study, the buildings where are located near Asia Cultural Complex (ACC) and leaved as idle spaces now that is used for important facilities are used to apply the multi-purposed emotional Space. Essential methodology and terminology were examined to estimate and construct the multi-purposed emotional space. Result: The multi-purposed emotional space provides that people aggressively request subjects to satisfy their emotional attractiveness as well as comforts and pleasures beyond the functional basic requirements in space. On the other words, it can be regarded as limited context to physical space responsive to social and environmental changes for the surrounding, and may maximize user experiences. Since emotions tend to be abstract and subjective while architectural space has pretty physical properties, this study attempts to integrate contrastive properties between emotional and architectural spaces to make a real object.

• Tribology and Lubricants
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• v.29 no.2
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• pp.111-116
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• 2013

This paper describes the adherence phenomenon, including the tribological characteristics, of a low-pressure fuel pump in a diesel engine for an excavator. Most fuel pumps of a diesel-engine excavator are of the fixed-quantity-gear type and have low pressure. However, the developed pumps develop problems in the pumping system owing to performance instability. Cavitation, which is the main obstacle to stable driving in the pump, occurs between an idle gear and the housing to produce a serious adherence problem. The present study not only examined how to suppress cavitation in a pump but also developed a simple method to improve pump performance through the early creation of a lubrication film with a phosphoric acid coating on the surface of the idle gear. The results showed that the coating successfully prevents breakage of the idle gear due to adherence.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.359-364
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• 2007

Spray characteristics of the APU gas turbine engine were investigated. In order to understand blow out phenomena of the APU engine, we performed fuel spray test. In the test, four operating conditions such as sea level idle, sea level max power, 20,000 feet idle, 20,000 feet max power were used as spray experimental conditions. PDPA(phase Doppler Particle Analyzer) was used for measuring the particle diameter and velocity. Also spray visualization was performed by using ND-YAG sheet laser beam. From the test result, in the case of 20,000 feet idle condition, SMD is about 100 ${\mu}m$ and maximum particle velocity is about 10 m/s. For the flame stability, spray quality should be improved at 20,000 feet idle condition.