• 한국대기환경학회지
• /
• 제14권5호
• /
• pp.443-454
• /
• 1998

Pt-V catalytic converter was installed on a heavy duty diesel engine and the characteristics of the emission reduction were tested using a engine dynamometer at various operating conditions. The emission reduction performance of Pt-V catalyst was also compared with that of a commercialized Pt catalyst currently being used in some of the heavy duty diesel engines in advanced countries. The effects of Pt-V and Pt catalysts on regulated and unregulated emissions were investigated using a 0.05 weight percent sulfur content fuel with an engine dynamometer Experiments for gaseous emissions (CO, HC and aldehyde) as well as particulate emissions (TPM, SOF and sulfate) have been conducted at several operating conditions such as T-7 mode, D-13 mode and S-13 mode before and after installing the Pt-V and Pt catalysts in the exhaust system. The emission reduction performance of Pt catalyst with respect to CO, HC, SOF, PAHs and aldehyde was found to be a little higher than that of Pt-V catalyst, but the Pt catalyst showed innate disadvantage of causing an increase of PM due to the sulfate formation via high SO2 conversion at high exhaust temperature, especially above 45$0^{\circ}C$.

• 한국자동차공학회논문집
• /
• 제21권1호
• /
• pp.61-67
• /
• 2013

In this paper, it was studied how the critical speed which could occur hot judder due to disk temperature. Through the dynamometer experiment, we measured the critical velocity and surface temperature when the hot judder occur on the disk break. Also with the critical velocity theory equation and the temperature change graph of factors which used in the equation, we was induced experiment equation including theory equation and experiment values. And it has compared with the method which approach as linea. From this, we predicted the change of critical speed which could occur hot judder due to disk temperature. In addition, critical speed graph has compared with actual driving speed and disc temperature at a vehicle test. Therefore it was estimate to possibility of arising hot judder.

• 한국대기환경학회지
• /
• 제22권3호
• /
• pp.383-391
• /
• 2006

In Korea, the major source of serious air pollution is motor vehicles. Air pollution from vehicles has been annually increased. Then the government will try to control the vehicle emission by applying the effective emission management policy for the manufactured and in-used car. It is necessary to correctly calculate the emission factor for successful propulsion of the vehicle emission control policy. In this study, correlation analysis of exhaust emissions from vehicles between CVS-75 mode and Korea mode was conducted. A total of 25 light-duty buses were tested on the chassis dynamometer system in order to measure CO, HC, NOx PM and fuel efficiency (F.E.). For the test modes, 10 different Korea modes and CVS-75 mode were used. As the result of correlation analysis between those modes, most of the correlation coefficients were higher than 0.90. On the basis of high correlation between those modes, correction factors by driving conditions were estimated. Through the results of this study, we obtained essential basic data to correct difference from those modes.

• 한국분무공학회지
• /
• 제17권3호
• /
• pp.152-157
• /
• 2012

This investigation decribes the effect of the combustion and emission characteristics of HCNG engine according to the high purity hydrogen contents. The HCNG fuel was made by the mixture with a high purity hydrogen ($H_2$) and a natural gas. The test vehicle was applied to the bi-fuel (Gasoline and CNG) system and this system was modified from the fuel supply and fuel tank. In addition, the three premixed HCNG fuels with mixed rate of 10, 20 and 30% of hydrogen were used to maintain the safety. In order to analyze the combustion characteristics of HCNG and CNG, the fuel was injected in the combustor with constant volume. The exhaust emission from light duty vehicle with bi-fuel system was analyzed by a chassis dynamometer and emission analyzer. From these results, the reduction rate of NOx emission increased in the HCNG fuel and emission amount of THC and CO shows a similar level with CNG fuel. This study can be utilized the basic data for the development of a new business plans related with HCNG engines.

• 한국수소및신에너지학회논문집
• /
• 제29권5호
• /
• pp.497-502
• /
• 2018

In Korea, passenger car and van using LPG fuel including taxi constantly increased due to the high cost of fuel. Recently, the emission standard has continuously tightened in the world. In this investigation was conducted the greenhouse gas emission characteristics of LPG vehicles according to the displacement and weight. Exhaust emission characteristics of 13 test LPG vehicles from about 1.0 L to 3.0 L displacements were measured and analyzed by using chassis dynamometer and emission analyzer. It is revealed that the greenhouse gas emission was showed the increasing tendency as the displacement and curb weight increased. Also, greenhouse gas emission of SC03 driving cycle has highest value and that of HWFET driving cycle shows the lowest value.

• Wind and Structures
• /
• 제28권3호
• /
• pp.155-170
• /
• 2019

This paper presents a novel test method for the galloping of iced conductor using wind generated by a moving vehicle which can produce relative wind field. The theoretical formula of transiting test is developed based on theoretical derivation and field test. The test devices of transiting test method for aerodynamic coefficient and galloping of an iced conductor are designed and assembled, respectively. The test method is then used to measure the aerodynamic coefficient and galloping of iced conductor which has been performed in the relevant literatures. Experimental results reveal that the theoretical formula of transiting test method for aerodynamic coefficient of iced conductor is accurate. Moreover, the driving wind speed measured by Pitot tube pressure sensors, as well as the lift and drag forces measured by dynamometer in the transiting test are stable and accurate. Vehicle vibration slightly influences the aerodynamic coefficients of the transiting test during driving in ideal conditions. Results of transiting test show that the tendencies of the aerodynamic coefficient curve are generally consistent with those of the wind tunnel tests in related studies. Meanwhile, the galloping is fairly consistent with that obtained through the wind tunnel test in the related literature. These studies validate the feasibility and effectiveness of the transiting test method. The present study on the transiting test method provides a novel testing method for research on the wind-resistance of iced conductor.

• 전기학회논문지P
• /
• 제63권3호
• /
• pp.143-148
• /
• 2014

This paper proposes a novel efficiency measurement method without dynamometer. In case of small motor, the measurement of efficiency is not easy because the percentage of mechanical loss is comparably huge and the mechanical loss is not easy to be measured. In this paper, the authors proposes a method which can measure the efficiency with two test motors. This method can be useful to engineers who study small electrical motors.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2006년도 추계학술대회 논문집
• /
• pp.197-198
• /
• 2006

• 대한정형외과스포츠의학회지
• /
• 제7권2호
• /
• pp.95-121
• /
• 2008

목적: 전방 십자 인대 재건술 후 임상적 결과 판정에 있어 IKDC 주관적 점수의 유용성을 알아보고자 하였다. 대상 및 방법: 전방 십자 인대 재건술을 시행 받은 24명의 환자를 대상으로 하였으며 이 중 12명은 자가 슬괵건, 12명은 아킬레스 동종건을 이용하였다. 주관적 평가 항목은 Lysholm 점수, IKDC 주관적 점수, Knee Outcome Survey (KOS) 점수 및 Tegner 활동도를 이용하였고, 정적 불안정 검사, Biodex 근력 평가 검사, 외발 뛰기 검사 등을 객관적 판정 검사로 시행하였다. 환자의 최종 결과 판정을 위해 Carioca test, Shuttle run test 및 Co-contraction test 등의 삼종 기능성 수행 검사를 시행하였고 각각의 검사 항목을 기능성 수행 검사와 비교하여 상관 관계를 도출하였다. 결과: IKDC 주관적 점수, 외발 뛰기 검사 중 한번 뛰기 및 저속에서의 대퇴 사두근의 근력 검사에서 기능성 수행 검사와 유의한 상관 관계를 보였다. 결론: IKDC 주관적 점수는 전방 십자 인대 재건술 후 주관적 결과 판정 뿐만 아니라 기능적 상태를 알 수 있는 유용한 검사로 사료된다.

• 전기학회논문지
• /
• 제61권12호
• /
• pp.1807-1812
• /
• 2012

In this paper, the d, q-axis inductance of IPMSM(Interior Permanent Magnet Synchronous Motor) was calculated by the FEA(Finite Element Analysis). And the CVCT(Current Vector Control Test) was performed, and compared with FEA. Therefore the inductance experiment according to the variation of the current phase angle was performed. However, the error was generated in the fundamental wave detection of the voltage and current waveform. So, error has largely effect on the result of computation, it has to note specially. In addition, by using the calculated inductance, the torque calculation was performed and this result was compared through the dynamometer experiment.