• Journal of The Korean Astronomical Society
• /
• v.20 no.2
• /
• pp.49-62
• /
• 1987

Using the detailed two-dimensional surface photometry of 39 galaxies, the observed profiles are decomposed into spheroid, disk and bar components simultaneously. From the analyses of decomposition parameters, the correlations among the three components are investigated to find the global property of barred galaxies. And the lens and ring components, and spiral arm patterns are also examined with Hubble type and decomposition parameters.

• Journal of Korean Society for Quality Management
• /
• v.26 no.1
• /
• pp.172-191
• /
• 1998

In this paper, dimension tolerance design for components is studied. Three cost factors are considered: machining cost, rework cost, and loss related to product quality which is affected by the tolerances of components. We propose a procedure to determine the optimal tolerances of components and a, pp.y the procedure to design the tolerances of fine motion stage in semicoduct machine. We compare the proposed procedure with the existing model for determining tolerance economically.

• Korean Journal of Pharmacognosy
• /
• v.1 no.1
• /
• pp.35-37
• /
• 1970

The methanol extract of two kinds of liquorice on Korean market was examined for basic components by a general alkaloid extraction method. The hydrochloride of the components gave all positive reactions to five coloration and precipitation tests. Four coloration tests on the thin-layer chromatograms of the free bases showed three to five spots which are considered to be basic.

• Structural Engineering and Mechanics
• /
• v.64 no.2
• /
• pp.213-223
• /
• 2017

Bridges are lifeline and integral components of transportation system that are susceptible to seismic actions, their vulnerability assessment is essential for seismic risk assessment and mitigation. The vulnerability assessment of bridges common in Pakistan is very important as it is seismically very active region and the available code for the seismic design of bridges is obsolete. This research presents seismic vulnerability assessment of three real case simply supported multi-span reinforced concrete bridges commonly found in northern Pakistan, having one, two and three bents with circular piers. The vulnerability assessment is carried through the non-linear dynamic time history analyses for the derivation of fragility curves. Finite element based numerical models of the bridges were developed in MIDAS CIVIL (2015) and analyzed through with non-linear dynamic and incremental dynamic analyses, using a suite of bridge-specific natural spectrum compatible ground motion records. Seismic responses of shear key, bearing pad, expansion joint and pier components of each bridges were recorded during analysis and retrieved for performance based analysis. Fragility curves were developed for the bearing pads, shear key, expansion joint and pier of the bridges that first reach ultimate limit state. Dynamic analysis and the derived fragility curves show that ultimate limit state of bearing pads, shear keys and expansion joints of the bridges exceed first, followed by the piers ultimate limit state for all the three bridges. Mean collapse capacities computed for all the components indicated that bearing pads, expansion joints, and shear keys exceed the ultimate limit state at lowest seismic intensities.

• International Journal of Reliability and Applications
• /
• v.11 no.2
• /
• pp.89-106
• /
• 2010

This paper deals with the reliability and availability characteristics of three different series system configurations with warm standby components and a repairable service station. The failure time of the primary and warm standby are assumed to be exponentially distributed with parameters ${\lambda}$ and ${\alpha}$ respectively. The repair time distribution of each server is also exponentially distributed with parameter ${\mu}$. The breakdown time and the repair time of the service station are also assumed exponentially distributed with parameters ${\gamma}$ and ${\beta}$ respectively. We derive the reliability dependent on time, availability dependent on time, the mean time to failure, $MTTF_i$, and the steady-state availability $A_i$(${\infty}$) for three configurations and perform comparisons. Comparisons are made for specific values of distribution parameters and of the cost of the components. The three configurations are ranked based on: $MTTF_i$, $A_i$(${\infty}$), and $C_i/B_i$ where $B_i$ is either $MTTF_i$ or $A_i$(${\infty}$).

• Journal of The Korean Association For Science Education
• /
• v.36 no.5
• /
• pp.769-781
• /
• 2016

This study investigated the interactions among the PCK components of pre-service secondary chemistry teachers considered in the processes of making written test items individually and in small groups. The processes of making written test items individually for 8 pre-service teachers was studied through the think-aloud method. The analysis of the results revealed that the 'assessment in science education' of the five PCK components was most frequently used in making test items. 'Curriculum for science education,' 'subject matter knowledge,' and 'students' were also frequently used although fewer than the previous component. However, 'instructional strategies and instruction for science education' was hardly used. The integrations between two or three components with various types were frequently found. However, integrations among four to five components were not found. The processes of making written test items in two small groups consisting of four pre-service teachers were observed. The analysis of the results revealed that the PCK components used in small groups were similar to those in the individual processes. However, 'curriculum for science education' was less frequently used, and the numbers of subcategories used at a relatively high frequency increased from other four components in small groups. In the aspects of integration, the proportion of the integrations between two components decreased and that for three components increased compared with those in the individual processes. The integrations among four or five components were also newly found. However, the integrations of 'curriculum for science education' with the other components were less frequently found. The integrations of 'instructional strategies and instruction for science education' with other components were still hardly found.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.11 no.2
• /
• pp.172-183
• /
• 2006

This paper analyzes instantaneous power compensation theory through comparing p-q theory and cross-vector theory which were proposed by Akagi and Nabae respectively in three-phase four-wire systems. The two compensation theories are identical when there is no zero-sequence voltage component in three-phase three-wire systems, However, when the zero-sequence voltage and/or current components exist in three-phase four-wire systems, the two compensation theories we different in definition on instantaneous real power and instantaneous imaginary power. Based on the analysis, this paper presents instantaneous power compensation method that can eliminate neutral current completely without using energy storage element when the zero-sequence current and voltage components exist in three-phase four-wire systems.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.21 no.2
• /
• pp.75-94
• /
• 2019

The Joseon Tongsinsa Festival has been held annually in May in Busan. It reenacts the procession of the Joseon Tongsinsa that the Joseon Government delegated to Japan four times in the 18th century. In the most important situation during the meandering period, three envoys (Jeongsa, Busa, Jongsagwan) who led the Joseon Tongsinsa, wore Jobok, but at the Joseon Tongsinsa Festival, the three envoys are wearing Jobok, which are not historically accurate. The Jobok called Geumgwan Jobok and were comprised of Yanggwan, Eui, Sang, Jungdan, Peasul, Su, Pumdae, Daedae, Paeok, Hall, Mal, and Hwa. These were ranked from first class to ninth class by personal ornamentation such as Yanggwan, Su, Pumdae, Paeok. So, this study is focused on ascertaining the Jobok of the 18th century for the three envoys who were ranked third grade. This study is based on literature, artifacts, and portraits that can depict the 18th century Jobok including all components. It was based on The 7th Korean Human Body Survey Final Report (2015) in order to produce all components of the Jobok of the modern males in their 50s who are playing the role of the three envoys in the Joseon Tongsinsa Festival.

• Journal of the Korean Society of Tobacco Science
• /
• v.20 no.1
• /
• pp.115-123
• /
• 1998

The semi-volatile fraction of cigarette mainstream smoke contains the most important aroma and taste that enhance smoke flavor. The components in mainstream smoke were analysed for commercially available cigarettes. To compare the semi-volatile components delivered from mainstream smoke of domestic cigarette with imported cigarette, we analyzed three types of filter cigarettes such as cellulose acetate mono filter, carbon dual filter and slim filter cigarette. Mainstream smoke was collected with a combination of Cambridge filter pad and liquid trap containing a small amount of acetone cooled by dry ice-methanol. We have identified 43 components from mainstream smoke by GC and GC/MS and found that benzene, toluene, 4-hydroxy-4-methyl-2-pentanone, 5-methyl-2-furaldehyde, acetic acids nicotine and triacetin were the main peaks in mainstream smoke. Also we have compared the relative amounts of semi-volatile compounds delivered from the domestic and imported cigarettes with three different filters. From the results of this study, the relative amounts of limonene, acetic acid, 5-methyl-Lfuraldehyde delivered from the imported cigarettes were generally higher than those of the domestic one's.

• Journal of Korean Society for Atmospheric Environment
• /
• v.10 no.E
• /
• pp.343-356
• /
• 1994

In this study, a statistical investigation was carried out for the evaluation of any relationship between polycyclic aromatic hydrocarbons (PAHss) associated with ambient aerosols and other air quality parameters under varying meteorological conditions. Daily measurements for PAHs and air quality/meteorological parameters were selected from a data-base constructed by a comprehensive air monitoring in London during 1985-1987. Correlation coefficients were calculated to examine any significant relationship between the PAHs and other individual variables. Statistical analysis was further Performed for the air quality/meteorological data set using a principal component analysis to derive important factors inherent in the interactions among the variables. A total of six components were identified, representing vehicle emission, photochemical activity/volatilization, space heating, atmospheric humidity, atmospheric stability, and wet deposition. It was found from a stepwise multiple regression analysis that the vehicle emission component is overall the most important factor contributing to the variability of PAHs concentrations at the monitoring site. The photochemical activity/volatilzation component appeared to be also an important factor particularly for the lower molecular weight PAHs. In general, the space heating component was found to be next important factor, while the contributions of other three components to the variance of each PAHs did not appear to be as much important as the first three components in most cases. However, a consistency for these components in their negative correlations with PAHs data was found, indicating their roles in the depletion of PAHs concentrations in the urban atmosphere.