• 응용통계연구
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• 제20권1호
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• pp.117-132
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• 2007

두 평정자가 있는 이차원 분류표에서 우연에 의한 합치 비율을 보정한 Cohen의 합치도($\kappa$)는 문제점이 있는 측도로 알려져 있다. $\kappa$는 평정자의 분류 비율(주변확률)에 매우 민감하고, 합치도로서의 조건도 만족하지 못한다. 그러나 $\kappa$를 비롯한 기존 합치도들은 주변확률이 0.5에 가까울 때 안정되며 비슷한 값을 갖는다. 본 연구에서는 이차원 분류표의 불균형적 주변분포를 보정함으로써 $\kappa$의 역설을 해결하는 새로운 합치도 H를 제안한다. 또한 예제를 통해 기존의 합치도들과 제안된 합치도를 비교한다.

• Communications for Statistical Applications and Methods
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• 제16권5호
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• pp.753-762
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• 2009

평정자간 일치 정도를 나타내는 측도로 주로 사용되는 k의 문제점을 해결하기 위해 박미희와 박용규(2007)는 $2{\times}2$ 분할표에서 새로운 합치도 H를 제안하였다. 본 연구에서는 이를 확장하여 $m{\times}m$ 분할표에 대한 합치도 H와 그 분산을 구한다. 또한 k의 역설과 주변분포와의 관계를 증명하고, $3{\times}3$ 분할표 예제를 이용하여 기존의 합치도들과 비교한다.

• Journal of Astronomy and Space Sciences
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• 제15권1호
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• pp.27-38
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• 1998

We discussed four different methods - the single, double and triple Gaussian fits, and the intensity weighted centroid fit - which extract rotation curves from several emis-sion lines(i.e. [OII], $H{\beta}$, [OIII], and $H{\alpha}$) of spiral galaxies. Spatial extents and the shapes of rotation curves derived through various methods applying to each emission lines of a sample galaxy UGC 11635 are all in a good agreement with one another. Linewidths of $H{\beta}$ and $H{\alpha}$ measure from rotation profiles are in a good agreement with $H{\alpha}$ linewidth of Courteau (1992). however, linewidths of [OII] seems to be much broader than $H{\alpha}$, and the profile of [OIII] does not follow the profile of $H{\alpha}$.

• 응용통계연구
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• 제22권5호
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• pp.1073-1084
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• 2009

두 평정자가 R개의 순서형 반응 범주로 각 개체를 분류한 $R{\times}R$ 분할표에 대해, 불합치의 정도를 가중치로 부여한 가중 합치도 $H_{\omega}$를 제안하고, 최대 우도추정량 및 분산을 유도하였다. 또한 $2{\times}2$ 분할표에서 Feinstein과 Cicchetti(1990)가 제기한 마지막 역설을 새롭게 정의하고 증명하였으며, ${\kappa}$의 새로운 역설을 제기하고, ${\kappa}$와 주변분포의 전반적인 관계를 정리하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.843-846
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• 2002

Unlike ordinary train, the HST(High Speed Train) is operated at a very high speed, which may cause pressure transient problems when the HST is passing through a station. In the present study, the wind pressure caused by the passing HST was measured in the Cheonan HST station and compared with the numerical simulations. For the measurement, the HST was passing through the station at speeds of 240 km/h north bound and 150 km/h south bound. MEMS based differential pressure transducers are used to measure pressure variation at various locations in the station. It is shown from the results that measured data are in good agreement with CFD simulation with moving mesh technique for the train movement. With the present validation of CFD simulation, the CFD simulation may effectively aid the design of future HST station.

• 한국분무공학회지
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• 제3권4호
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• pp.35-42
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• 1998

Laser Raman scattering method has been applied to measure equivalence ratio of methane/air and propane/air mixture in constant volume combustion chamber. We used high power KrF excimer laser$(\lambda=248nm)$ and a high gain ICCD camera to capture low intensity Raman signal. Raman shifts and Ram cross-sections of $H_2,\;O_2,\;N_2,\;CO_2,\;CH_4\;and\;C_3H_8$ were measured precisely. Our results showed an excellent agreement with other groups. Mole fraction measurement of $O_2\;and\;N_2$ from air showed that $O_2\;:\;N_2$ = 0.206 : 0.794. We used constant volume combustion chamber and gas injector which is operated at $5\sim10barg$. Methane and propane are used as a fuel. 50 Raman signal are obtained and ensemble averaged for measurement of equivalence ratio. Our measured results showed that the equivalence ratio of fuel/air mixture is reasonable at ${\pm}5%$ error range.

• 소성∙가공
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• 제24권4호
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• pp.293-298
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• 2015

A safety vent is crucial to protect its user from unpredictable explosions caused by increasing internal pressure of the lithium-ion batteries. In order to prevent the explosion of the battery, a safety vent rupture is required when the internal pressure reaches a critical value. In conventional manufacturing, the cap plate and the safety vent are fabricated separately and subsequently welded to each other. In the current study, a manufacturing process including a backward extrusion and coining process is suggested to produce an integral safety vent which also has the benefit of increasing production efficiency. FE simulations were conducted to predict the rupture pressure and to design the safety vent using a ductile fracture criterion and the element deletion method. The critical value, C, in the ductile fracture criterion was obtained from uniaxial tensile tests with an annealed sheet of 1050-H14 aluminum alloy. Rupture tests were preformed to measure the rupture pressure of the safety vent. The results met the required rupture pressure within 8.5±0.5 kgf/cm². The simulation results were compared with experimental results, which showed that the predicted rupture pressures are in good agreement with experimentally measured ones with a maximum error of only 3.9%.

• 한국분무공학회지
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• 제2권4호
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• pp.7-14
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• 1997

Laser Raman scattering method has been applied to measure equivalence ratio of methane/air mixture in injected spray. We used high power KrF excimer laser$(\lambda=248nm)$ and a high gain ICCD camera to capture low intensity signal. Raman shifts and Raman scattering cross -sections of $H_2,\;O_2,\;N_2,\;CO_2,\;CH_4\;and\;C_3H_8$ are measured precisely. Our results show an excellent agreement with those of other groups. Mole fraction measurement of $O_2\;and\;N_2$ from air shows that $O_2:N_2=0.206:0.794$. We used gas injector which was operated at 1 bar. Methane is used as a fuel. Spray region is $10mm\times37mm$ and this region is divided into 80 points. In Raman signals are obtained and ensemble averaged for each point. 3-d and contour plot of distribution of equuivalence ratio is presented. Our measured results show that the equivalence ratio of methane/air mixture in methane-rich region is reasonable. However, more study is necessary for methane-lean region because background noise level is almost same as Raman intensity of methane.

• Macromolecular Research
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• 제17권10호
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• pp.763-769
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• 2009

A chromatographic method is used to measure interactions between dissimilar proteins in aqueous electrolyte solutions as a function of ionic strength, salt type, and pH. One protein is immobilized on the surface of the stationary phase, and the other is dissolved in electrolyte solution conditions flowing over that surface. The relative retention of proteins reflects the mean interactions between immobile and mobile proteins. The osmotic cross second virial coefficient calculated by assuming a proposed potential function shows that the interactions of unfavorable proteins depend on solution conditions, and the proposed model shows good agreement with the experimental data of the given systems.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1993년도 추계학술발표회 초록집
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• pp.31-36
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• 1993

Three different methods were employed to measure the degree of aerial oxidation in coal and the resulting oxidation/weathering indices were applied to obtain kinetic parameters of aerial oxidation processes, The index (i.e., slurry pH, Free Swelling Index, weight gain) values were subjected to kinetic analysis based on power-law Arrhenius type reaction model. The results show that activation energy of the aerial oxidation in 20-29$0^{\circ}C$ is in the range of 12-16 ㎉/㏖ and the agreement among three techniques is remarkable. The first order kinetic model is suitable in describing low temperature aerial oxidation process, except in the FSI case where the zero order expression is the best one.