• Journal of the korean Society of Automotive Engineers
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• v.10 no.3
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• pp.45-50
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• 1988

The measurement system of the pressure in engine cylinder is developed with the aids of the microcomputer, A/D converter and simple electrical circuits. The experiment is performed in 4 cycle single cylinder Gasoline engine. When data for the pressure progress is sampled, clock signal or signal from the crank angle is used as trigger. The variation of the pressure during the cycles can be well obtained experimentally. So, the informations which are necessary in the combustion analysis, i.e. expansion pressure, indicated mean effective pressure, the magnitude and time of the maximum pressure ignition time, the rate of pressure rise and heat release and combustion rates can be obtained by the calculation using experimental data. Also, the informations about the after-burning process, the existence of the detonation waves and end time of combustion can be investigated from this study.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2002.05a
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• pp.70-73
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• 2002

Using a simple compression test, the viscosity measurement experiment is carried out with the grain-refined Al-Si alloy(A356). The measured rheological data are expressed with power-law(Ostwald-de Waele) model and using commercial package, MAGMAsoft, coefficients of Ostwald-de Waele model and Carreau-Yasuda model are calculated. To verify the viscosity data, the die is designed to be applicable to the semi-solid die casting of automotive component and filling test is carried out. The filling test and the simulation result are compared and in good agreement. Hereafter, these data are considered to be usefully allied other product in the semi-solid die casting.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.303-306
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• 2008

This study proposes an essential process of type certificate, which is load comparison for proving the calculated design load. The load measurement was carried out according to IEC 61400-13 standard and the load calculation was performed with same condition using FLEX 5 code. For more accurate load simulation, the controller parameter of original model at the design stage was modified to site optimized value and some node points are added to coincidence with measurement. The load comparison was performed with various wind parameter, turbulence intensity and wind shear. As a result, simulated loads ware good agreed with the measured load. Therefore, the calculated design loads according to IEC 61400-1 standard were proved to valid.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.6
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• pp.790-794
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• 2004

The study is about practical use of the computer program developed to obtain more efficient and accurate photographic measurement of body. Measuring measurements automatically using this program, the observational errors can be reduced considerably, so that the accuracy of photographic measurement are improved. The program has several functions as follow; First, free rotation of body by horizontal and perpendicular control of photo data. Second, recognition of body outline of photo data and automatic measuring of 45 basic items as well as freehand measuring of height, width, depth, angle. Third, obtaining database of photographic measurements of each subject without additional process such as data input.

• Journal of Sensor Science and Technology
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• v.18 no.6
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• pp.441-448
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• 2009

Magnesia partially stabilized zirconia(Mg-PSZ) solid electrolytes for an improvement of thermal shock resistance, which is suitable for the measurement of oxygen activity in a molten steel, were prepared by post-thermal aging treatment. The steelmaking oxygen sensor elements were formed by an injection molding method, sintered at $1650^{\circ}C$, and then thermal aged ranged from 1250 to $1400^{\circ}C$. Sintered density and porosity were decreased as increasing the magnesia content in a zirconia-magnesia solid solution. Fractions of cubic phase to the synthesized Mg-PSZ solid electrolytes were ranged from 13.13 to 79.54.% after post-thermal aging treatment. Very dense microstructure without voids in the grains was obtained by the post-thermal aging process. Fine tetragonal phase crystallites precipitated on the cubic surface during post-thermal aging up to $1300^{\circ}C$ improve a thermal shock resistance and reappearance of electro motive force(EMF) curve.

• Proceedings of the KIEE Conference
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• 1998.07b
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• pp.426-428
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• 1998

In this paper we describe a real time signal processing technique for the code correletion short range measurement sensor. Code correlation values are acquired via simple RC charging circuits within several tens of microsecond. Because the range measuring process is very fast and simple, the proposed technique is applicable to common near range targets as well as fast moving targets in real time. Some experimental results show the validity and usefulness of the proposed method.

• Proceedings of the KIEE Conference
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• 1997.07b
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• pp.462-464
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• 1997

In this paper we propose a new RF range measurement method. Using two codes which have different chip rate, we transmit one code toward the direction of targets and calculate the distance by comparing it with the other untransmitted reference code. Because the measuring process is fully digitalized, the stability, resolution, flexibility, and compactness of the system are good. Some experimental results are provided to show the validity and the performance of the proposed method.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.2
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• pp.182-187
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• 1988

Hot carrier induced device degradation characteristics under DC bias stress have been investigated in n-MOSFETs with channel length of 1.2,1.8 um, and compared with those of LDD structure device with same channel length. Based on these results, the device lifetime in normal operating bias(Vgs=Vds=5V) is evaluated. The lifetimes of conventional and LDD n-MOSFET with channel length of 1.2 um are estimated about for 17 days and for 12 years, respectively. The degradation rate of LDD n-MOSFET under the same stress is the lowest at n-region implnatation dose of 2.5E15 cm-\ulcorner while the substrate current is the lowest at the dose of 1E13cm-\ulcorner Thses results show that the device degradation characteristics are basic measurement parameter to find optimum process conditions in LDD devices and evaluate a reliability of sub-micron device.

• Journal of the Korean Society for Railway
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• v.6 no.4
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• pp.232-238
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• 2003

A health monitoring system becomes a very useful tool to obtain information on long term behavior of the important railway structures such as very long span and special type bridges. It can be also used to give a warning signal to the maintenance engineer when the structure shows abnormal behavior. However, due to long term use and temperature changes, the health monitoring system needs to be calibrated periodically. In this study, calibration and gauge factor readjustment process made for the health monitoring system installed in the railroad bridges and tunnel are reviewed and a few findings are updated. Future work will be concentrated on the long-term analysis of the measurement data and on the database structures so that the assessment of the structure is possible

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.2242-2249
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• 2008

A severe problem in VE study of a project is to reduce value due to loss of performance, caused by focusing on cost reduction. Also a lack of understanding performance concept, no trial VE workshop as well as cost saving-based policy have not satisfied customer needs. A efficient VE job plan for especially large scale railroad construction project is proposed in this study. This study developed a more objective performance evaluation system for value engineering study of mega projects and suggested a systematic process of performance quantitative analysis for value improvement. The proposed performance measurement method would be very useful for better communication and consensus between decision makers and VE team.