• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.6
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• pp.1-8
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• 2000

A new method of knock detection in SI engines, using a change of ion concentration in the combustion chamber, was developed. In order to measure in-cylinder ionization current, ionization probes were installed at spark plug and cylinder head of production engine. It was found that the electric current generated by ionized gas in core burned gas region of knocking cycle is between 2 and 10 times larger than that of normal cycle, because the burned gas temperature which is the dominant parameter of a change of ion concentration increases. However, a change of ionization current in boundary region of burned gas is relatively weak. Hence a change of ion concentration in core burned gas region can be used for knock detection.

• Journal of the Korean Society of Industry Convergence
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• v.2 no.2
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• pp.155-163
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• 1999

In this study, single cylinder engines with different tumble ratio were made to find out in-cylinder fluid motion and flame propagation. Tumble ratio derived from the steady state flow rig test. Flame propagation speed was obtained using cylinder head gasket ionization probe and the piston ionization probe. And the combustion pressure in cylinder was measured to analyze the combustion characteristics. In case of high tumble engine, BSFC and BSHC were decreased and BSNOx was increased at part load test. Also BMEP and combustion peak pressure was increased at full load test. Tumble flow motion had an great effects on initial burning period rather than main burning period in part load test.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.5
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• pp.511-517
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• 2019

Two type pistons which had different configuration were made to find out the effects on combustion and flame propagation. Flame propagation speed was obtained by use of the cylinder head gasket ionization probe. Ionization Probe voltage output and flame propagation speed were increased according to the air fuel mixture ratio increase. Exhaust direction flame propagation speed was fastest in combustion chamber and next was front direction, rear direction and intake direction cause of tumbling motion in cylinder. In case of remove the valve pocket in piston, average flame propagation speed changed slowly and spark timing was advanced. Also emission was decreased.

• 한국연소학회:학술대회논문집
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• 2002.11a
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• pp.223-229
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• 2002

Spark plug ionization signal could be useful in an internal combustion engine as a feedback signal for combustion diagnostics such as misfire detection, knocking detection and lambda control, but the signal has high level of cyclic fluctuation in an internal combustion engine due to residual gas, pressure, temperature, mixture composition in the spark gap. Because of this reason it is very difficult to apply ion signal to commercial engine control. In this Study, a correlation between A/F and spark plug ionization signal was studied in a constant volume chamber. Constant volume chamber with gas phase fuel(Propane) has homogeneous fuel composition , no mixture flow, same pressure and temperature on each test. The results show that mean chemi-ion signal has the highest correlation with A/F and intial pressure change has on effect on the thermal-ion signal and not on chemi-ion signal.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.5
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• pp.191-198
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• 1998

In this study, the effects of water vapor in inlet air, spark advance and fuel type in the spark ignition engine were investigated through the experiments of combustion and flame arriving pattern analysis using ionization probe. The results of flame propagation experiment using ionization probe show that the flame which ignited from spark plug located at the center of the combustion chamber propagated faster in exhaust side than in intake side due to the mixture flow motion inducted into combustion chamber from intake tumble port at all conditions. And as the partial vapor pressure increased, the flame propagation became slower in all direction. Especially effects were greater for intake side than the exhaust side.

• Journal of the Semiconductor & Display Technology
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• v.13 no.4
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• pp.1-5
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• 2014

The plasma density distribution in between the electrode and lateral wall of a narrow gap CCP was investigated. The plasma density distribution was obtained using single Langmuir probe, having two peaks of density distribution at the center of electrode and at the peripheral area of electrodes. The plasma density distribution was compared with the RF fluctuation of plasma potential taken from capacitive probe. Ionization reactions obtained from numerical analysis using CFD-$ACE^+$ fluid model based code. The peaks in two region for plasma density and voltage fluctuation have similar spatial distribution according to input power. It was found that plasma density distribution between the electrode and the lateral wall is closely related with the local ionization.

• Archives of Pharmacal Research
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• v.7 no.1
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• pp.23-31
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• 1984

An improved mass spectrometric method for multicomponent analysis of metabolites in urine, well-suited for clinical biochemistry, is described. The method involves solvent elution of the metabolites from an adsorbent and the concentration of the eluate on a microadsorption column. This is administered by a direct inlet probe into the ionizing source of field ionization mass spectrometry (FIMS), which yield a molecular weight profile of the metabolites. The procedure provides rapidly (within one hour) reproducible profiles from a small volume of urine. The optimization of the sampling technique and the reproducibility are discussed.

• Journal of Astronomy and Space Sciences
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• v.39 no.3
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• pp.117-126
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• 2022

The Ionospheric Anomaly Monitoring by Magnetometer And Plasma-probe (IAMMAP) is one of the scientific instruments for the Compact Advanced Satellite 500-3 (CAS 500-3) which is planned to be launched by Korean Space Launch Vehicle in 2024. The main scientific objective of IAMMAP is to understand the complicated correlation between the equatorial electro-jet (EEJ) and the equatorial ionization anomaly (EIA) which play important roles in the dynamics of the ionospheric plasma in the dayside equator region. IAMMAP consists of an impedance probe (IP) for precise plasma measurement and magnetometers for EEJ current estimation. The designated sun-synchronous orbit along the quasi-meridional plane makes the instrument suitable for studying the EIA and EEJ. The newly-devised IP is expected to obtain the electron density of the ionosphere with unprecedented precision by measuring the upper-hybrid frequency (f_UHR) of the ionospheric plasma, which is not affected by the satellite geometry, the spacecraft potential, or contamination unlike conventional Langmuir probes. A set of temperature-tolerant precision fluxgate magnetometers, called Adaptive In-phase MAGnetometer, is employed also for studying the complicated current system in the ionosphere and magnetosphere, which is particularly related with the EEJ caused by the potential difference along the zonal direction.

• Mass Spectrometry Letters
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• v.3 no.2
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• pp.29-38
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• 2012

A new approach of volatile compounds analysis is proposed using a linear ion trap Orbitrap mass spectrometer coupled with gas chromatography through an atmospheric pressure photoionization interface. In the proposed GC-HRMS/MS approach, direct chemical composition analysis is made for the precursor ions in high resolution MS spectra and the structural identifications were made through the database search of high quality MS/MS spectra. Successful analysis of a complex perfume sample was demonstrated and compared with GC-EI-Q and GC-EI-TOF. The current approach is complementary to conventional GC-EI-MS analysis and can identify low abundance co-eluting compounds. Toluene co-sprayed as a dopant through API probe significantly enhanced ionization of certain compounds and reduced oxidation during the ionization.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.11a
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• pp.192-193
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• 2012

2차 플라즈마를 사용하지 않고도 스퍼터링된 입자의 높은 이온화율을 얻을 수 있는 고전력 마그네트론 스퍼터링 기술은 최대 $MW/cm^2$의 높은 투입 전력을 이용하지만 타겟 재료의 높은 열전도 요구때문에 실제로 사용할 수 있는 재료가 Cu를 비롯한 몇가지 금속에 제한된다. 수 백 $kW/cm^2$의 중간 전력 밀도를 가질 수 있도록 펄스를 다중 부분 세트로 제어하는 modulated pulse plasma 시스템을 구축하고 전자 온도, 밀도를 고속으로 계측할 수 있는 삼중 프로브와 고증폭 CCD를 이용하여 공정 진단을 한 결과 전자 온도는 최고 15.9 eV, 전자 밀도는 $4.25{\times}10^{12}{\sharp}/cm^3$였으며 weak ionization 조건과 strong ionization 조건에서 Ar I (811.5 nm)의 방출광 세기가 6배 증가하는 것으로 분석되었다.