• Journal of the Korea Institute of Building Construction
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• v.12 no.2
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• pp.194-202
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• 2012

This paper predicts the cementing efficiency of fly-ash(FA) based on mortar test considering binder-water ratio and FA replacement ratio as experimental variables. The cementing efficiency prediction model proposed by statistical analysis enables us to estimate the value according to the binder-water ratio and FA replacement ratio of matrix. When FA replacement ratio is the same, the lower the binder-water ratio, the higher the estimated cementing efficiency. There are significant differences in the values according to binder-water ratio at FA replacement ratios of 15% or less, but there are almost no differences when FA replacement ratio is more than 15%. As the binder-water ratio increases, the variations in the values according to FA replacement ratio are great at FA replacement ratios of 15% or less. As the FA replacement ratios increase, the values increase for FA replacement ratios of 15% or less, but decrease for more than 15%. The values range from -0.71 to 1.24 at binder-water ratio of 1.67-2.86 and FA replacement ratio of 0-70%. The RMSE of the 28-day compressive strength predicted by modified water-cement ratio is 2.2 MPa. The values can be trusted, as there is good agreement between predicted strength and experimental strength.

• Journal of KSNVE
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• v.7 no.6
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• pp.1039-1048
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• 1997

This paper describes the effects of dual dynamic vibration absorbers attached to a primary vibration system with damping. The efficiency of dual dynamic vibration absorbers was investigated with the height of amplitude ratio at the resonance frequency ratio of the damped vibration system according to mass ratio, natural frequency ratio and damping ratio. The variation of amplitude ratio related to frequency ratio of primary vibration system is verified experimentally and theoretically according to dual dynamic vibration systems using computer program designed to find mutual relationship between two absorbers.

• Korean Journal of Organic Agriculture
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• v.28 no.1
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• pp.59-68
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• 2020

This study analyzed and suggested management situations and improving issues on a consumer cooperatives which has supplied environmentally friendly agricultural products from the year 2002. Indices of management analysis are stability ratio, activity ratio and profitability ratio. Management Stability ratio indices are debt ratio, net worth ratio, fixed ratio and current ratio. Management activity ratio ones include fixed assets turnover and net worth turnover. And profitability ratio is showed through return on investment, net return on sales and return on equity. In order to analyze these indices, financial statements after the closing entires are used each year.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.4 s.117
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• pp.105-115
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• 2006

Biotope Area Ratio ($BFF; BiotopFl{\"{a}}chenFaktor$) was developed in Berlin, Germany in 1990s and introduced to Korea in 1999. It is the ratio of the uncovered soil areas which have the natural circulating capability compared to whole development areas. This study seeks for alternative ways to increase Biotope Area Ratio of residential areas in the metropolitan areas of Korea by investigation on new housing developments. The study investigates four new towns including Seoul Eunpyung new town, Yongin Kusung district, Goyang Pungdong and Juyeopdong districts and Hwasung Dongtan district. The Biotope Area Ratio of study sites is between 23.51 % and 40.69%. This result is not relevant to land use conditions, such as the building-ta-land ratio, natural ground green area ratio. This ratio satisfies the minimum requirements of City of Seoul, except 2 sites. Considering that the study sites are relatively low density land use areas compared to Seoul's average, thus, a higher standards is necessary for new town housing complexes. Because Biotope Area Ratio includes artificial ground green area ratio, Biotope Area Ratio is possible can be increased with decreased natural ground green area ratio. And so, when Biotope Area Ratio is applied to new town development, it must go side by side with a definite natural ground green area ratio.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.3 s.168
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• pp.86-92
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• 2005

In this paper a forward-backward can extrusion process are analyzed by using rigid-plastic FEM simulation. FEM simulation is conducted to investigate forming characteristics such as deformation modes fur different process parameters. Design parameters such as thickness ratio, punch angle, friction factor and diameter ratio are selected to study the effect of them on the pattern of material flow. The analysis is focused mainly on the influences of the design factors on deformation pattern in terms of forming load, extruded length ratio and volume ratio. It is known for the simulation that the forming load, the length ratio and the volume ratio increase as the thickness ratio (TR), the wall thickness in forward direction to that in backward direction, decreases. The various punch angles have slight influence on the forming load. length ratio and volume ratio. However friction factor have little effect on the forming characteristics such as the forming load, volume ratio and so on. In addition the forming load increases as diameter ratio (DR), the outer diameter of a can in forward direction to that in backward direction, increases. Furthermore the extruded length ratio is lowest with a certain value of DR=0.85 among diameter ratios. Pressure distribution exerted on the die-material interface is illustrated schematically.

• The Korean Journal of Health Service Management
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• v.6 no.4
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• pp.111-120
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• 2012

This research analyzes on the factors and difference of the management performance in general hospital. In details, we provide that personnel expenses, materials costs and administrative expenses have impact on management performance in general hospital and these factors have differences by region and sickbed size. The meaningful results of this study as follow. In the first, personnel expenses ratio influence management performance but materials costs ratio and administrative expenses ratio are only partially impact for the management performance. Secondly, in the management performance by region, there are no significant differences between the two groups of the big city and small and medium-sized cities. In personnel expenses ratio, materials costs ratio and administrative expenses ratio, The materials costs ratio is significant difference but ersonne expenses ratio and administrative expenses ratio have no significant difference. Finally, there's no significant difference between the hospital size and management performance. But this study provide that there is partially a difference between personnel expenses ratio, materials costs ratio and administrative expenses ratio and the hospital size.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.2
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• pp.223-231
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• 2004

In most previous studies, the assessment of accommodative convergence to accommodative stimulus (AC/A) ratio was commonly made by measuring gradient AC/A ratio. This study deals with the proximal convergence/accommodation(PC/A)ratio measured by comparing values of the gradient AC/A ratio and the calculated AC/A ratio to prevail the clinical use of the AC/A ratio. Visual acuities of All 124 subjects had been corrected to at least 1.0 with either eye through their habitual refractive correction and the MEM dynamic retinoscopy was performed to estimate their accommodative response. And then the PC/A ratio was calculated by making use of the calculated AC/A ratio and the gradient AC/A ratio. This study showed that the difference between the mean calculated AC/A ratio and the mean gradient AC/A ratio in subgroups may be attributable to proximal convergence. Consequently, further studies on proximity cues including the PC/A ratio could be helpful to prevail the clinical use of the AC/A ratio.

• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.2
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• pp.53-60
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• 2011

This study was conducted to investigate the effect of hydropower factors (watershed, gross head), operation ratio and unit electricity cost on the benefit-cost ratio (B/C ratio) of small hydropower using agricultural reservoirs. The equation of B/C ratio was expressed as a function of watershed area, gross head, operation ratio and unit electricity cost. The benefit increased with watershed area, gross head and unit electricity cost, while the cost increased with watershed area and gross head but decreased with operation ratio. The B/C ratio increased with watershed area, gross head, operation ratio and unit electricity cost. While the effect of gross head on the B/C ratio decreased with watershed area, the effect of operation ratio and unit electricity cost on the B/C ratio increased with watershed area. The operation ratio is an important factor to affect the B/C ratio and therefore we need to develop hydropower for the heightened dams to expect high operation ratio due to continuous water release. The unit electricity cost is also an important factor to affect the B/C ratio and the B/C ratio was always below 1 unless unit electricity cost is over 60 Won/kWh under given conditions. The reservoirs with economic feasibility for small hydropower development were three in 21 when the equation of B/C ratio was appled to the study reservoirs. The results can be used to choose the appropriate reservoir with economic feasibility for development of small hydropower.

• Journal of the Korean Society of Safety
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• v.15 no.4
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• pp.123-126
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• 2000

This study shows consolidation properties resulted from the experiment made on changes by load increment ratio and consolidation duration of standard consolidation test using deposit soil of Chungju Dam. Though the comparison and analysis of the result turned out that void ratio by load increment ratio was unchanged greatly, the result was inclined as followes : the smaller load increment ratio is, the bigger void ratio is, while the bigger load increment ratio is the bigger settlement is. Also coefficient of consolidation is increased in inverse ratio to load increment ratio. Coefficient of permeability is increased in proportion to load increment ratio, it is not fixed changes by consolidation duration, however. Degree of consolidation is increased to load increment ratio.

• Journal of the Korea Society of Computer and Information
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• v.4 no.3
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• pp.114-120
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• 1999

This Paper is analyzing the Financial Ratio of Business in Korea under the IMF Regulations. In this Paper, First. the change condition of the Financial Ratio of Business in Korea before and after IMF. Second, Whether the Performance and Financial State of Business in Korea are right or not is examined by comparing the Financial Ratio of Business in Korea with Standard Financial Ratio. Finally, The Problems of the Financial Ratio of Business under the IMF Regulations are found, so the Ideas which can improve the problems are suggested, The Financial Ratio is analyzed by Stability Ratio. Profitability Ratio, Activity Ratio. Growth Ratio and Productivity Ratio.