• Korean Journal of Food Science and Technology
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• v.15 no.1
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• pp.56-61
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• 1983

Direct production of biomass from starch using amylolytic yeast, Sporobolomyces holsaticus FRI Y-5 was studied with varying the ratios between carbon and other nutrient sources in the medium. It was investigated under condition of constant C/P and C/S ratio to influence the initial concentration of starch $(S_o)$ and C/N ratio on its growth which is described as the specific growth rate $({\mu})$, cell yield (Y), the maximum concentration of cell $(X_m)$, and productivity (P). They were very dependent on both $S_o$ and C/N ratio. The form of the relationship between and ${\mu}$ and $S_o$ was observed to be similar to saturation kinetics at C/N = 100 but presented substrate inhibition at other C/N ratios. As $S_o$ was changed from 22.5 to 90 g/l, Y was observed to vary with C/N ratios but seemed to decrease as a wholes. $X_m$ was linearly related to $S_o$ at more than C/N = 50 but at less than C/N = 10 substrate inhibition was presented. P increased suddenly to $S_o$ = 45 g/l and then changed decreasingly at less than C/N = 50, but at more than C/N = 100 it changed increasingly. The effect of C/P ratio and C/S ratio on the yeast growth was also investigated at constant $S_o$ and C/N ratio. ${\mu}$ was dependent on C/P and C/S ratios, but Y, independent on them. But $X_m$ was reliant upon C/P ratio but not upon C/S ratio.

• Korean Journal of Applied Biomechanics
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• v.29 no.4
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• pp.213-217
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• 2019

Objective: The purpose of this study was to investigate the ratio of carrie's and run's distance in golf running approach using 52° and 48° wedges. Method: 2 women's professional golfers from the LKPGA were given the running approach in the 5 m, 10 m, 15 m respectively. The variables were analyzed through a golf analyzer and actual measurement. Results: If you send 5 m with 52° and 48° wedges, the ball run about 5 m, 10 m respectively, if you carry 10 m with 52° and 48° wedges, the ball run about 10 m, 13 m respectively. And if you carry 15 m with 52° and 48° wedges, the ball run about 13 m, 15 m respectively. Conclusion: Based on the results, if you are confident in distance, if you choose the club properly and if you are confident, if you try to send the correct distance to the hole cup, then you will have a more confident approach, which will lead to better results.

• Journal of the Korean Institute of Gas
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• v.24 no.3
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• pp.20-26
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• 2020

In this study, experimental study was conducted to examine the influence of explosion pressure and flame propagation velocity of methane-air mixtures due to the obstacles placed in the explosion space. We used the quantified parameter named barrier ratio in order to generalize the effect of explosion pressure and flame propagation velocity in the closed explosion space with obstacles. From experimental observations, the explosion pressure and flame propagation velocity regardless of the number of obstacles increased with barrier ratio. In the same methane concentration of 10% methane, the flame propagation velocity without obstacle (barrier ratio = 0) was 3.46 m/s but 24.24 m/s (increase about 7 times) with 3 obstacle and barrier ratio of 0.98. In the same barrier ratio, explosion pressure and flame propagation velocity increased sharply with increasing of the number of obstacles.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.11
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• pp.923-932
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• 2006

In this paper, reentering ratio and cooling capacity of individual cooling towers arrayed on a building roof were studied by a numerical method. The number of 16 cooling towers were divided into 4 banks. It was considered the summer prevailing wind characteristics as west wind and south wind of 5 m/s. It was also considered the roofwall types as the curtainwall and the louverwall that had the outdoor air intake louver in the curtainwall. In this case, the louver was suggested as the solution that could prevent reentering phenomenon due to recirculation and interference of the discharge air. In the case of the curtainwall, the averaged reentering ratio are predicted 13.3% and 24.4% for the west and south wind of 5 m/s, respectively. In the case of the louverwall, the averaged reentering ratio are predicted 2.5% and 9.7% for the west and south wind of 5 m/s, respectively. Therefore, the louverwall is a appropriate solution for reducing the reentering phenomenon.

• Current Research on Agriculture and Life Sciences
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• v.31 no.4
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• pp.233-239
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• 2013

Understanding the temporal variability of agricultural parameters derived from historical climate data is important for planning in agriculture. Therefore, this study assessed the magnitude and recent trends of the transpiration ratio defined as the crop water use per harvested yield for the period from 1980 to 2010. The crop water use was estimated using the Food and Agriculture Organization's Crop Wat model for eight administrative provinces in Korea. The temporal trends and spatial uncertainty were explored using the Mann-Kendall and Theil Sen's methods. The regional average rice yield was $6.31t\;ha^{-1}$(range 5.9 to $6.9t\;ha^{-1}$). The results showed that the rice yield in Korea increased by $26kg\;ha^{-1}yr^{-1}$. Overall, the regional average transpiration ratio was $1,298m^3t^{-1}$ (range 1,162 to $1,470m^3t^{-1}$). From 1980 to 2010, the transpiration ratio decreased by $8.2m^3t^{-1}$ (range 2.7 to $14.4m^3t^{-1}$), largely as a result of the increasing yield. The statistical approach to historical data used in this study also provides a basis for simulating the future transpiration ratio.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.1
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• pp.81-85
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• 1996

Microwave dielectric properties of 0.15(B $a_{x}$S $r_{0.05}$)O-0.15(S $m_{2}$(1-y)N $d_{2y}$) $O_{3}$-0.7Ti $o_{2}$(x=o.9~0.1[mol.], y=6[m/o]) ceramics were investigated with BaO compositional ratio. Sintered density and resistivity of specimens were independent on the BaO compositional ratio. In the specimen with x=0.975[mol.], dielectric constant, quality factor and temperature coefficient of resonant frequency had good values of 76.52, 3001(at 3[GHz]) and +0.71[ppm/.ceg. C], respectively. By comparing with the stoichiometric compositions of 78.14, 2938(at 3[GHz])+14.19[ppm/.ceg. C], dielectric constant and quality factor showed similar properties, but the temperature coefficient of resonant frequency was highly improved. (author). refs., figs., tabs.s.s.

• Korean Journal of Community Nutrition
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• v.27 no.4
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• pp.321-340
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• 2022

Objectives: This study established a practical direction for the prevention and management of metabolic syndrome by evaluating the health status, nutrition intake level, and diet quality according to metabolic syndrome and related drug treatment in Korean adults. Methods: The data from the 2017 KNHANES (Korea National Health and Nutrition Examination Survey) was analyzed. The analysis included 2,978 adults, classified into the normal, metabolic syndrome (MetS), metabolic syndrome with medicines (MetS-M), and without medicines (MetS-noM) groups. The nutrient intake, NAR (nutrient adequacy ratio), INQ (index of nutritional quality), and DDS (dietary diversity score) were analyzed. Results: The mean BMI was significantly higher in the MetS group than in the normal group for all subjects. Subjects of the MetS group tended to consume less energy and major nutrients, while males aged 50 ~ 64 and all females showed less intake of nutrients in the MetS-M group. The energy intake ratio was within 55 ~ 65 : 7~ 20 : 15 ~ 30 of KDRI (Korean Dietary Recommended Intake), but the carbohydrate energy ratio of all subjects aged 50 to 64 was over 65%. The NAR of the major nutrients was lower in the MetS-M group, the average INQ was around 0.8, especially the INQ of calcium and vitamin A was less than 1, and the total DDS score was less than 4 points. Conclusions: This study confirmed that the nutrient intake and diet quality differed among subjects diagnosed with metabolic syndrome and managed with medical care. The intakes of energy and many nutrients, the quality of diets, and the diversity of food groups in the MetS-M group were lower than in the normal group. Therefore, these will be an important basis for establishing a specific direction of diet education for preventing and managing metabolic syndrome according to gender, age, metabolic syndrome, and drug treatment.

• Geophysics and Geophysical Exploration
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• v.16 no.3
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• pp.109-118
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• 2013

On and near the 23-m high earthen Cheongcheon dam in Boryeong City, Korea, short seismic refraction and surface-wave profiles were conducted using a 5-kg sledgehammer. From vertical and horizontal components of the seismic waves, near-surface P-wave velocities (${\nu}_p$) and S-wave velocities (${\nu}_s$) were derived by inverting first-arrival refraction times and dispersion curves of Rayleigh waves. Average ${\nu}_p$ and ${\nu}_s$ for the Jurassic sedimentary basement were determined to be 1650 and 950 m/s at a depth of 30 m directly beneath the dam and 1650 m/s and 940 m/s at a depth of 10 m at the toe of the dam, respectively. The dynamic Poisson's ratio for these strata were therefore in the range of 0.24 to 0.25, which is consistent with ratios for consolidated sedimentary strata. Near a 45-m borehole 152 m downstream from the dam crest, an SH tomogram indicates a refraction boundary with an average ${\nu}_s$ of 870 m/s at depths of 10 ~ 12 m. At this site, the overburden comprises the upper layer with relatively constant ${\nu}_p$ and ${\nu}_s$ around 500 and 200 m/s, respectively, and the lower layer in which both ${\nu}_p$ and ${\nu}_s$ increase with depth almost linearly. The dynamic Poisson's ratios for the overburden were in the range of 0.30 to 0.43.

• Nuclear Engineering and Technology
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• v.51 no.2
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• pp.384-393
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• 2019

An experimental validation of a nuclear forensics methodology for the source reactor-type discrimination of separated weapons-useable plutonium is presented. The methodology uses measured values of intra-element isotope ratios of plutonium and fission product contaminants. MCNP radiation transport codes were used for various reactor core modeling and fuel burnup simulations. A reactor-dependent library of intra-element isotope ratio values as a function of burnup and time since irradiation was created from the simulation results. The experimental validation of the methodology was achieved by performing two low-burnup experimental irradiations, resulting in distinct fuel samples containing sub-milligram quantities of weapons-useable plutonium. The irradiated samples were subjected to gamma and mass spectrometry to measure several intra-element isotope ratios. For each reactor in the library, a maximum likelihood calculation was utilized to compare the measured and simulated intra-element isotope ratio values, producing a likelihood value which is proportional to the probability of observing the measured ratio values, given a particular reactor in the library. The measured intra-element isotope ratio values of both irradiated samples and its comparison with the simulation predictions using maximum likelihood analyses are presented. The analyses validate the nuclear forensics methodology developed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.1050-1053
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• 2002

This paper presents metal structure that is fabricated using UV-LIGA process with PMER N-CA3000. In order to fabricate metal structure with high aspect ratio, the systematic optimization method was adopted and then the structure of $36{\mu}m$ thick mold with aspect ratio 7:1 (trench) and $32{\mu}m$ thick nickel structure was obtained. This structure is applied to the fabrication of optical switch.