• Journal of the Korean Society of Combustion
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• v.16 no.1
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• pp.1-7
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• 2011

340 MWe circulating fluidized bed (CFB) boiler in Yeosu power station is under construction. The circulating fluidized bed boiler in the Yeosu power plant has a number of differences from other domestic boilers in terms of scale and design. Evaluation of design parameters of the Yeosu CFB boiler should be required because the direct application of existing technology is limited. In this study, design characteristics of the Yeosu CFB boiler was summarized. And thermogravimetric analysis was conducted with comparing other rank coals. Watersteam side heat absorption, flue gas temperature and heat transfer coefficient were calculated by heat and mass balance. Design parameters for the Yeosu CFB boiler were discussed along with typical value in the CFB design range.

• Korea Journal of Hospital Management
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• v.17 no.4
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• pp.87-115
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• 2012

This research classified hospital specialization strategy types through cluster analysis, analyzed fitness of hospital specialization strategy types for external environment or organizational structure, and examined relation between hospital specialization strategy types and organizational performance. This research surveyed 1,437 hospitals which have more than 30 patient's bed and practice national health service in Korea. Specifically, this research divided into two part : external fit - analysis of relation between external environment and specialization strategy, internal fit-analysis of relation between organizational structure factors and specialization strategy. also, as the organizational performance for achieving specialization strategic purpose, not only the productivity, efficiency, profit but also the medical quality was considered. In case of external fit, many hospitals chose integration type if there are a lot of competitive hospitals and regional population. Particularly, if there are many competitive hospitals, concentration type is chosen. In contrast, if there are many doctors in the region, differentiation type is chosen. In case of internal fit, according to organization type and patient's bed number, hospitals chose different types. If it is a general hospital and has a few bed number, generalization or concentration type is chosen. Tertiary hospital or the hospital with many patient's bed chose differentiation type. According to the number of specialists, if there are a few specialists, generalization or concentration type is chosen. If there are many specialists, differentiation type has high fitness for the hospital. In relation to strategy types and organizational performance, differentiation type has best result. Differentiation type has a good result in 7 items out of 11.

• Water for future
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• v.26 no.4
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• pp.107-115
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• 1993

The results of laboratory experiments on the clear-water local scour of cohesionless bed sediment at three types of the pier shape are presented. Based on the experimental data, the relative equilibrium depth of local scour is related to the pier shape, the geometric standard deviation of the bed material, the velocity ratio and the pier Froude number. The relative local scour depths were smallest ant the round-nosed pier and remarkably reduced at the non-uniform bed sediment, comparing with those at the uniform bed material. The effect of sediment grading on the local scour reduction was discussed and compared with Raudkivi and Ettema's experiments.

• Journal of the Korean Society of Combustion
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• v.3 no.1
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• pp.41-48
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• 1998

A numerical study on combustion in a fluidized bed is based on three dimensional mixing and dispersion phenomena in the bed owing to the bubble growth in the vertical direction. As fluidizing velocities increase, bubble diameters increase, which activates the fuel dispersion in the bed. The combustion rates, however, reduce due to the decrease of gas exchange rates between bubble and emulsion phases. Fuel distributions in the bed are dependent on fluidizing velocities, equivalence ratios, fuel particle diameters, fuel feeding points, and the number of fuel feeders.

• Journal of The Korea Institute of Healthcare Architecture
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• v.22 no.4
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• pp.67-77
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• 2016

Purpose: This paper aimis to analyze the characteristics of ward plan of Korean hospital architecture constructed in each periods and identify the change since 1945. Methods: Literature review was conducted while ward plans for analysis were sellected. And then the important points of ward design were analyzed in each periods. Results: The important points of ward design - type of corridor in ward plan, number of beds per nursing unit, location of nurse station, organization of multi-bed rooms, location of patient toilet, number of day room, concentration and separation of elevator halls for patient and general- were analyzed and the characteristics of change were identified in each periods. Implications: This paper could be a basic data for arranging the history of hospital architecture in Korea.

• Journal of Ginseng Research
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• v.19 no.3
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• pp.287-290
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• 1995

This study was conducted to elucidate the effect of physical properties of soil in nursery bed with different densities on growth of ginseng seedling. Stem length, leaf length and leaf width of ginseng seedling showed the decreasing tendency with increasing the hardness of the nursery soil. Fresh root weight per seedling and number of available seedlings were increased significantly with decrease of the soil hardness. For solid, liquid phases, bulk density and hardness of soil, negative correlations were shown in stem length, leaf length, leaf width, root weight per seeding, and number t of available seedlings. On the other hand, gas phase, air permeability and porosity of soil had positive correlations with stem length, leaf length, leaf width, root weight per seedling and number of available seedlings. Key words Yang-Jik nursery, ginseng seedling, soil physical properties.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.4
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• pp.123-129
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• 1993

Because the existing scour prediction formulas for plunge pools of pipe culverts and spillways give a wide range of predicted scour depths, it is difficult to estimate actual scour depths. A review of literature showed that wide range of predicted values was caused mostly by lack of thorough analysis of the scour mechanism. In this study, the effects of the parameters govering scour were examined, and the scour potentials were measured. The major variables govering scour were the velocity and size of jet impinging into the plunge pool, the submerged weight of bed material, the ratio of jet size to bed material size, the tail watr depth of the plunge pool, and the angle of jet impact on water surface. The ratio of jet size to bed material size to bed material size was found to be another significant parameter affecting scour for larger bed materials. A densimetric Froude nember of the bed material in incipient motion was formulated. This number represented the scour potential of the jet at the point where the bed material was tested.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.6
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• pp.1395-1404
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• 1994

Transverse bed slope in bend is a subject of scientific investigation since it provides the necessary information for channel design and protection of hydraulic structures (bank, bridge, etc), and study of river morphology. In this paper, selected models were examined and compared for the value of prediction of the transverse bed slope in curved alluvial channels(project area), by using field data, and fitting model was proposed. All models that related the local transverse bed slope to mean flow characteristics were alike in the sense that they predicted the local transverse bed slope to be proportional to the ratio between depth and radius of curvature. The difference among the models was related with the factor of proportionality, K. Also, measured transverse bed slope was correlated to mean velocity, maximum depth, and density Froude number in channel bend. In this paper selected models were compared for the prediction of the transverse bed slope using Odgaard's experiment (obtained in Sacramento River bend), so Odgaard89 model was closely related with real transverse bed slope.

• Korean Journal of Environment and Ecology
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• v.22 no.1
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• pp.43-58
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• 2008

For this study, which was conducted in the summer from $2004\sim2007$, 10 small and medium sized streams in Korea were selected(Munsan and Gokreung Stream in the Han River watershed, Mi, Ssanggye and Nam Stream in the Nakdong River watershed, Gapeong and Jojong Stream in the Bukhan River watershed, Cheongmi, Yanghwa and Bokha Stream in the Namhan River watershed), and plant surveys were performed using the belt transect method on the most natural 1km sections of each stream in order to clarify the natural environment condition of the plants in each stream. In the results of the plant survey, the total number of plant species recorded was 296. After selecting 121 species of those surveyed plant in order of frequency, an RDA(Redundancy Analysis) and a Pearson Correlation Analysis were performed to determine the correlation between the selected plant species and environmental factors( such as distance from channel, size of bed material, number of bars, altitude, bed slope, width of channel, and measured data of water quality) of the study sites. There was no significant correlation between the 121 plant species and altitude, bed slope, and number of bars at the research sites, but the correlation of plant species with size of bed material, width of channel, electrical conductivity, and phosphate$(PO_4-P)$ concentration was from very high to moderate. Also, the spectrum of these plant species reflects the actual environmental conditions so the method used in the study seems to be correct, but owing to the range of diversity, the results of the study seem to be difficult to extend to other streams. Nevertheless, it is expected that this data can be used as a basic material for researching plants by stream characteristics or in selecting plant species for streams.

• Geomechanics and Engineering
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• v.36 no.2
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• pp.121-130
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• 2024

Many foundation projects are built on red-bed soft rocks, and the damage evolution of this kind of rocks affects the safety of these projects. At present, there is insufficient research on the damage evolution of red-bed soft rocks, especially the progressive process from mesoscopic texture change to macroscopic elastoplastic deformation. Therefore, based on the dual-porosity characteristics of pores and fissures in soft rock, we adopted a cellular automata model to simulate the propagation of these voids in soft rocks under an external load. Further, we established a macro-mesoscopic damage model of red-bed soft rocks, and its reliability was verified by tests. The results indicate that the relationship between the number and voids size conformed to a quartic polynomial, whereas the relationship between the damage variable and damage porosity conformed to a logistic curve. The damage porosity was affected by dual-porosity parameters such as the fractal dimension of pores and fissures. We verified the reliability of the model by comparing the test results with an established damage model. Our research results described the progressive process from mesoscopic texture change to macroscopic elastoplastic deformation and provided a theoretical basis for the damage evolution of these rocks.