• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.4
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• pp.618-624
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• 1998

This study was conducted to standardize ingredient ratios of wooung kimchi. The ingredient ratios of model wooung kimchiwere determined by the survey in Pusan and Kyungnam province and using the literatures including cooking books. Several kinds of wooung kimchi were prepared by adjusting the ingredient ratios fo the model wooung kimchi within standard deviation. The wooung kimchi with different ingredient ratios were fermented for 6 days at 15$^{\circ}C$. The chemical, microbial and sensory properties of the wooung kimchi were investigated. There was little change in pH but the counts of lactic acid bacteria were decreased, as the ratio of pickled anchovy juice became high. The wooung kimchi adding 9.4% pickled anchovy juice obtained high score in appearance and overall acceptability. The counts of lactic acid bacteria were increased in wooung kimchi adding 5% red pepper powder, and there was obtained better result in appearance, texture and overall acceptability than the other groups. The activity, reducing sugar and counts of lactic acid bacteria were increased, as the ratio of glutinous rice paste became high. The wooung kimchi including 6% glutinous rice paste showed the highest score in overall acceptability. The fermentation process of wooung kimchi accelerated, as the ratio of garlic became high. The wooung kimchi adding 3% garlic showed good appearance and acceptability. In addition to these, the addition of 1.3% ginger ehhanced the appearance, texture and overall acceptability fermented anchovy juice, 5.0% red pepper powder, 6.0% glutinous rice paste, 3.0% crushed garlic and 1.3% crushed ginger.

• Journal of ILASS-Korea
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• v.22 no.1
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• pp.13-21
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• 2017

The fog screen is a device projecting the media to the aerosol flow field. As major parameters to generate dense and steady fog screen, shear stress, optical blockage ratio and SMD were obtained result through experiment. The micro droplet was generated by the piezo oscillation element, and the aerosol flow mixed with an air flow was sprayed into the vertical direction from the top of the fog screen through the 280 mm slot. For produce a dense, uniform fog screen, the shear effect, optical blockage ratio and SMD between aerosol and air curtain were measured. The minimum and maximum shear stress conditions were selected and it was confirmed that the optical transmission deviation of the aerosol flow field was small when the aerosol and air curtain flow rates were changed. When the aerosol and air curtain flow power were 18 V (1.51 m/s) and 24 V (2.55 m/s), respectively, under the condition of the minimum shear stress and laminar flow, the optical blockage ratios with the spray length were small, and it produced a most stable and high density uniform fog screen by injecting a constant of $10{\mu}m$ or less.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.2
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• pp.39-48
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• 2003

This paper present a summary of the results of statistical study of the ductility factor which is key component of response modification factor(R). To compute the ductility factor, a group of 1,860 ground motions recorded from various earthquake was considered. Based on the local site conditions at the recording station, ground motions were classified into four groups according to average shear wave velocity. Inleastic spectrum were computed for elastic perfectly plastic SDOF systems undergoing different level of inelastic deformation and period. Ductility factors were calculated by deviding elastic response spectrum by inelastic response spectrum. The influence f displacement ductility ratio, site condition, magnitude and epicentral distance on ductility factors were studied. The coefficient of variation was computed to evaluated the dispersion of ductility factors as the defined ratio of the standard deviation to the mean.

• Bulletin of the Society of Naval Architects of Korea
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• v.11 no.2
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• pp.1-6
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• 1974

The three-dimensional correction factor of the added mass of finite-length elliptic cylinders in vertical vibration in a free surface was calculated. This problem has already been dealt by T. Kumai[5] to contribute to analytical prediction of the three-dimensional correction factor for the added mass in vertical vibration of ships. In Kumai's work, the body boundary condition involved in the appropriate boundary value problem was approximately treated in the course of obtaining the solution. In this work, obtaining the solution derived from mathematically exact treatment of the body boundary condition, the author recalculated the three-dimensional correction factor for length-beam ratio $4{\sim}8$, beam-draught ratio $2.00{\sim}4.50$ and number of nodes from 2 to 7. And the numerical results were compared with both Kumai's results and the author's experimental data for two and three-noded vibrations of the cylinder of beam-draught ratio 2.40 The comparison of the numerical results shows that the author's are always higher than the Kumai's as expected. And the comparison of the numerical results with experimental data shows that the Kumai's numerical results have less deviation in case of two-noded vibration, and that, in case of three-noded vibration, the author's numerical results are in fairly good correspondence.

• Journal of Korean Association for Spatial Structures
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• v.18 no.1
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• pp.77-84
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• 2018

The identification of damping ratios in buildings is a well-known problem and appears to be of important and crucial interest in the safety and serviceability design. When compared to an estimation of the stiffness, i.e. natural frequency, and mass, the damping ratio is the most difficult quantity to determine. Many previous studies have examined the characteristics of damping ratios from ambient vibration, but the measurement time is roughly within 2 hours. In this paper, characteristics of damping ratios and natural frequencies of 4 story RC building were investigated using long-term ambient vibration. Free vibrations were obtained using random decrement technique, and damping ratios were evaluated by the envelop function, continuous wavelet transform, and logarithmic decrement. It was found that although the natural frequencies show little variations with time, the damping ratios show some variations with time and the largest variations found in the damping ratios obtained from the continuous wavelet transform. The damping ratios from the envelop function showed the smallest mean and standard deviation. And the probability distribution of damping ratios seems to follow the logarithmic normal distribution.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.768-773
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• 2004

When a gas expands through a convergent nozzle in which the ratio of the ambient to the stagnation pressures is higher than that of the critical one, the issuing jet from the nozzle is underexpanded. If a flat plate is placed normal to the jet at a certain distance from the nozzle, a detached shock wave is formed at a region between the nozzle exit and the plate. In general, supersonic moist air jet technologies with nonequilibrium condensation are very often applied to industrial manufacturing processes. In spite of the importance in major characteristics of the supersonic moist air jets impinging to a solid body, its qualitative characteristics can not even know. In the present study, the effect of the nonequilibrium condensation on the underexpanded moist air jet impinging on a vertical flat plate is investigated experimentally. Flow visualization and impact pressure measurement are performed for various relative humidities and flat plate positions. The obtained results show the plate shock and Mach disk are dependent on the nozzle pressure ratio and the relative humidity, but for a given nozzle pressure ratio, the diameters of the plate shock and Mach disk depend on the stagnation relative humidity. The impact pressure deviation from the flow of without condensation is large, as the relative stagnation humidity increases.

• The Mathematical Education
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• v.51 no.4
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• pp.395-413
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• 2012

National Assessment of Educational Achievement(NAEA) is important standard reference to become the basic data for confirming the effect of the curriculum administrated and the educational policies put in force presently and preparing the new curriculum and educational policies. In this paper, we looked into the mean and standard deviation of the calibrated score of whole group and male/female students, the correct answer ratio of each performance level and the correct answer ratio of each content domain, etc. in the results of NAEA at 6th elementary school. The analytic objects are 2010 and 2011 NAEA that are changed into complete enumeration survey and the standard reference prepared on the basis of the new calibrated score is applied to. And we analysed and compared correct answer ratio of the each content domain and each item to conform the difference between male and female students. On the basis of the these informations, we investigated that here is what kind of characteristics and trends to the whole group and what kind of suggestions to the teaching-learning. And we were going to provide the information of the needs to understand which content of mathematics is needed and which thinking methods are needed.

• Journal of the Korean Society of Clothing and Textiles
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• v.43 no.5
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• pp.768-777
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• 2019

This study established a lower garment sizing system for elderly men over 65 years of age based on 535 males selected from the 5th Korean Anthropometric survey. The results are as follows. Most elderly men body measurements were smaller for adult males (except for the waist area); however, abdominal obesity has changed to body type. The standard deviation was applied around the average values of waist circumference and hip circumference for the suggestion of a lower garment sizing system for elderly men. The interval between the designation was ${\pm}2.5cm$ with an average waist circumference of 86 cm and ${\pm}2cm$ with an average hip circumference of 92 cm. A total of 13 designation sections were established in consideration of the cover ratio and cover efficiency. The cover ratio in the 13 nominal sections was 77.2%. The segmental distribution rate presented in the results will also be useful for production planning in specific sizes and enable rational production.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.118-118
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• 2020

This study investigates the change of flow characteristics over 10 Asian river basins in the past 30 years (1976-2005). The variation is estimated from The Soil and Water Assessment Tool (SWAT) model outputs based on reanalysis data which was bias-corrected for Asian monsoon reagion. The model was firstly calibrated and validated using observed data for daily streamflow. Four statistical criteria were applied to evaluate the model performance, including Coefficient of determination (R2), Nash - Sutcliffe model efficiency coeffi cient (NSE), Root mean square error-observations standard deviation ratio (RSR), and Percentage Bias (PBIAS). Then parameters of the model were applied for the historical period 1976-2005. The estimates show a temporal non-considerable increasing rate of daily streamflow in most of the basins over the past 30 years. The difference of monthly discharge becomes more significant during the months in the wet season (June to September) in all basins. The seasonal runoff shows significant difference in Summer and Autumn, when the rainfall intensity is higher. The line showing averaged runoff/rainfall ratio in all basins is sharp, presenting high variation of seasonal runoff/rainfall ratio from season to season.

• Journal of Science Education
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• v.36 no.2
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• pp.394-407
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• 2012

This study analyzed the result of the National Assessment of Educational Achievement (NAEA) in a Grade 9 Science class. The study first found that the ratio of below basic achievement was 8.1 percent. This means that a large number of middle school students have not reached basic scientific literacy. Second, the ratio of male students in the below basic level was 10.4 percent, which was double the ratio of female students at 5.5 percent. Third, according to the analysis of achievement by gender, female students outperformed male students. In addition, the female students' standard deviation was smaller than that of the male students, and their scaled scores were distributed nearer the average than that of the male students. Furthermore, analysis of achievement by content domains indicated that females outperformed in all content domains including motion and energy, materials, life, and earth sciences. Showing a similar tendency in the behavior domains, females outperformed males in all behavior domains except the understanding domain. Last, for achievement by living area, students living in the middle and small cities showed the highest scaled score, 196.81. Whereas the average scaled score of the students living in the big cities was 196.15; that of the students living in rural areas was 194.86. With respect to the standard deviation, big cities had the largest, 33.73. That of middle and small cities was 33.70, and of rural areas was 32.92. Although students in cities showed higher achievement in science compared to students in rural areas, they had a bigger gap in academic achievement.