• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.77-78
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• 2015

Laminar burning velocities have been predicted by constant volume combustion chamber, counter flow burner and others. In this study, the measured flame propagation velocities in an assembled annular stepwise diverging tube were plotted with respect to equivalence ratio, length scale, and velocity scale. Three dimensional approach to understand the flame propagation velocity including laminar burning velocity is investigated, and the surface provides the correlation among quenching distance, propagation velocity, and equivalence ratio.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.4
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• pp.1064-1071
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• 1994

There are three active radicals which become to the scale of flame diagnostics at the flame front. They are OH, CH and $C_2$ radical. For this, optical measurement system which could monitor simultaneously the luminous waves of three radicals, was constructed. These were analyzed statistically into the cross correlation, coherence and phase. Through such an statistical treatment, combustion characteristics was investigated at the primary zone of gas turbine combustor. The local equivalence ratio was predicted with the ratio of luminuous intensity between CH and $C_2$ radical. This result was matched up to the equivalence ratio calculated from gas composition within 5% error. In general, equivalence ratio was said to be 1.0 at flame front, but it could be increased up to about 1.2 depending on the degree of swirl intensity in case of changing properly the air amount of primary zone.

• Journal of the Korean Home Economics Association
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• v.35 no.2
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• pp.333-344
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• 1997

The purpose of this study was to investigate new method to incorporate demographic variables into demand models through modifying the theory in an attempt to capture interactions between individuals within a household. The method which utilizes household equivalence scale was very attractive in the sense that it provide less restrictive implications for the behavior model, and thus, the estimated expenditure elasticities might be more realistic because demographic variables are more elaborately controlled. the household equivalence scaled was developed using Lagrange Interpolation Polynomials. Then the empirical model with household equivalence scale was derived based on the model of Deaton and Muellbauer. For its empirical utilization, Consumer Expenditure survey(CES) conducted by the bureau of Labor Statistics(BLS) was used.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.5
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• pp.367-373
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• 2008

A series of fire experiments has been conducted to provide an improved understanding of the fire structure of under-ventilated compartment fires. A comprehensive and quantitative assessment of gaseous species from the fire was made in the upper layer of fire in a 40 % reduced scale ISO 9705 fire compartment. The global equivalence ratio (GER) concept was used to characterize the fire behavior for various fire sizes, fuel types and ventilation conditions. The oxygen concentration in the upper layer reached to zero near the global equivalence ratio of $0.4{\sim}0.6$ while the carbon monoxide concentration increases with increasing the global equivalence ratio. Classification parameters of ISO19706 were also compared with the reduced scale experimental data for under ventilation fire.

• Journal of Korean Academy of Nursing Administration
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• v.13 no.4
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• pp.509-515
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• 2007

Purpose: The purpose of this study was to translate and validate the Korean version of Hall's Professional Inventory(HPI) scale to assess levels of professionalism among Korean registered nurses. Method: The 25 item HPI scale was translated and content review was done by translation panel. After the content review, a bilingual nursing scholar performed the back-translation into English. A semantic equivalence test was conducted with 5 American nursing professors. A pilot study was conducted with a sample of 164 registered nurses in Korea to test the validity and reliability of the translated HPI. Result: The content equivalence for translated version of HPI was validated by a translation panel. The finding of the semantic equivalence test of back-translated version was 72.8%. The Cronbach's alpha for the Korean version of HPI was .820. Conclusions: This study provides information about the issues of translating an instrument such as the HPI. The Korean version of the HPI is a valid and reliable instrument and can have psychometric properties equivalent to those of the original HPI. The translated version could be used for assessing levels of professionalism for other health care professionalism as well as nurses.

• Journal of the Korean Society of Combustion
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• v.15 no.3
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• pp.32-39
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• 2010

An experimental study was conducted to investigate the relationship between global equivalence ratio(GER) and fire characteristics in an ISO 9705 room. Heptane fuel was burned with different fuel flow rates and doorway widths in order to force the room to be placed in different GER conditions. It was observed that after the onset of under-ventilated fire conditions, temperature and unburned fuel components such as CO and soot increased with increasing heat release rate (HRR), regardless of the doorway width. From the analysis of local mixture fraction, it was reconfirmed that the inclusion of soot production in the product composition was very important to predict accurately the chemical conditions inside the compartment, particularly for the under-ventilated fire conditions. In addition, the local equivalence ratio (LER) was directly proportional to the GER with a unit gradient regardless of doorway width when the soot production was included in the chemical products. This finding provided an important potential that the GER could be used to correlate the local thermal and chemical environment measured at the upper layer of a full-scale enclosure when soot was included.

• Journal of Mechanical Science and Technology
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• v.18 no.8
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• pp.1479-1489
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• 2004

The effect of fluctuation of Equivalence Ratio (ER) in a turbulent reactive field has been studied in order to check the global combustion characteristics induced by the local fluctuation. When the flow is premixed on a large scale, closer examination on a small scale reveals that local fluctuations of ER exist in an imperfectly premixed mixture, and that these fluctuations must be considered to correctly estimate the mean reaction rate. The fluctuation effect is analyzed with DNS by considering the joint PDF of reactive scalar and ER, followed by modeling study where an extension of stochastic mixing models accounting for the ER fluctuation is reviewed and tested. It was found that models prediction capability as well as its potential is in favor to this case accounting the local ER fluctuation. However, the effect of local fluctuation did not show any notable changes on the mean global characteristics of combustion when statistical independence between the reactive scalar and ER field is imposed, though it greatly influenced the joint PDF distribution. The importance of taking into account the statistical dependency between ER and combustible at the initial phase is demonstrated by testing the modeled reaction rate.

• Physical Therapy Korea
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• v.22 no.4
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• pp.51-61
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• 2015

The purpose of this study were to translate the Fullerton Advanced Balance (FAB) scale into Korean and to verify the content validity by utilizing a back-translation method with a view to assessing balance function and the risk of falling in a clinical research setting. This research was conducted in six steps. First, three Korean physical therapists translated the FAB scale into Korean. Second, two bilingual professors of physical therapy and a physical therapist evaluated translation conformity of Korean-translated FAB scale. In the third and fourth steps, twelve physical therapists evaluated the degree of translation comprehension, and a translator back-translated the Korean FAB scale into the original language. Fifth, a bilingual professor of physical therapy and two native speakers evaluated the technical and conceptual equivalence between the original and translation versions. In this process, inappropriate translated items were revised using recommended substitute words or sentences, and all items were evaluated on the basis of three points or more on a rating scale in terms of translation comprehension, and the technical and conceptual equivalence of the back-translation. In the sixth and last step, the translation verification committee completed the final Korean version. The above process indicated that the content validity of the Korean-translated FAB scale was established by means of systematic translation methods, and it can therefore be used to assess balance function and the risk of falls in a clinical research setting.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1146-1151
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• 2004

Measurements of OH chemiluminescence in an atmospheric pressure, laboratory-scale dump combustor at equivalence ratios ranging from 0.63 to 0.89 were reported. The signal from the first electronically excited state of OH to ground state was detected through a band-pass filter with an ICCD. The objectives of this study are two: One is to see the effects of equivalence ratio on global heat release rate and local Rayleigh index distribution. To get the local Rayleigh index distribution, the line-of-sight images were inverted by tomographic method, such as Abel de-convolution. Another aim is to investigate the validity of using OH chemiluminescence acquired with an ICCD as a qualitative measure of local heat release. For constant inlet velocity and temperature, the overall intensities of OH emission acquired at different equivalence ratio showed periodic and higher value at high equivalence ratio. OH intensity averaged over one period of pressure increased exponentially with equivalence ratio. Local Rayleigh index distribution clearly showed the region of amplifying or damping the combustion instability as equivalence ratio increased. It could provide an information/insights on active control such as secondary fuel injection. Finally, local heat release rate derived from reconstructed OH images were presented for typical locations.

• Journal of the Korean Society for information Management
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• v.21 no.2
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• pp.1-21
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• 2004

For the guarantee of retrieval ratio, thesaurus's maintenance for descriptors are necessary. To maintain the optimum scale of thesaurus, new terms and existing terms should be structured to the equivalence relationship. Therefore, equivalence relationships are needed to new standard. This study proposes new standard of the equivalence relationships, which is more specified for better guarantee of retrieval ratios. The relationships have seven facets. These six facets will be used as new knowledge-base, which could be reestablished between the descriptors.