• Korean Journal of Medicinal Crop Science
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• v.9 no.4
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• pp.251-258
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• 2001

Medicinal plant extracts including Rubus coreanus, Sanguisorba officinalis, Eriobotrya japonica, Prunus mume, Crataegus pinnatifida, Rosa leavaigate Prunus persica, Prunus japonica var. nakaii and Spiraea blumei were prepared for the test of antibacterial activity. Tryptic soy broth (TSB) containing $0{\sim}10mg/ml$ of medicinal plant extracts was inoculated with $10^6$ cells/ml of Staphylococcus aureus and incubated at $35^{\circ}C$ for 24 hours. The plate counting method and clear zone test were used to test inhibitory effect of the extracts. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was derived from the survival curves of S. aureus. The order of antibacterial activities of medicinal plant extracts on the S. aureus was Rubus coreanus > Sanguisorba officinalis > Eriobotrya japonica > Prunus mume > Crataegus pinnatfida. Minimum inhibitory concentration of Sanguisorba ofEcmalis on the Staphylococcus aureus was 2.5mg/ml and minimum bactericidal concentration of Rubus coreanus was 1.0%. Inhibition zone of Rubus coreanus, Sanguisorba officinalis, Eriobotrya japonica, Prunus mume, and Crataegus pinnatifida was 16.5mm, 14.3mm 11.0mm, 14.0mm and 12.7mm, respectively. The morphology of S. aureus cells treated with medicinal plant extracts showed damage of cell wall and cytoplasmic membrane. Severely damaged cells of S. aureus lost electron dense material and cytoplasm. This result suggests that medicinal plant extracts can be used as an effective natural antibacterial agent in food.

• Journal of Pharmacopuncture
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• v.12 no.3
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• pp.41-47
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• 2009

Objectives : This experimental study was performed to investigate the efficacy of Fel Ursi, Bovis Calculus & Moschus pharmacopuncture solution manufactured with freezing dryness method to use eye drop. Methods : After administering Fel Ursi, Bovis Calculus & Moschus pharmacopuncture solution on bacterial species(Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) which cause Keratitis, MIC(Minimum Inhibition Concentration) and the size of inhibition zone were measured. Anti-bacterial potency was also measured using the size of inhibition zone. Results : There was no response to MIC on bacterial species(Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) after Fel Ursi, Bovis Calculus & Moschus pharmacopuncture solution was medicated. Conclusions : The present study suggests that Fel Ursi, Bovis Calculus & Moschus pharmacopuncture solution dosen't have anti-bacterial effects on bacterial species(Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) which cause Keratitis. These study result recommends that more research on other herbal medicines of eye drop for Keratitis are required.

• The Korean Journal of Community Living Science
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• v.24 no.1
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• pp.27-36
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• 2013

This study was performed to investigate the antimicrobial effect against food-borne pathogens of Sanguisorbae officinalis L. ethanol extract. The antimicrobial activity of the ethanol extract was determined using a paper disc-diffusion method and the diameter of the clear zone was measured. The diameters of the clear zone in the presence of 10 mg of the ethanol extract were the maximum against Staphylococcus aureus among the tested 4 gram-positive bacteria and Pseudomonas aeruginosa among the tested 7 gram-negative bacteria. Analysis of the minimum inhibition concentrations (MIC) showed that the ethanol extract exhibited a similar efficacy as sorbic acid, well-known chemical preservatives. The growth inhibitory effects of the ethanol extract in the concentrations of 250, 500, 1,000 and 2,000 mg/L on food-borne pathogens were determined against Staphylococcus aureus, Bacillus subtilis, Salmonella Typhimurium and Pseudomonas aeruginosa. The growth of the microorganisms was significantly (p<0.05) inhibited by the ethanol extract in the concentrations higher than 250 mg/L. Thus, the results of the present study demonstrate that the ethanol extract exhibits antimicrobial effects against food-borne pathogens, suggesting that Sanguisorbae officinalis L. could be used as natural antibacterial agent in food.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.1
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• pp.1-12
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• 2021

In the design of a tunnel boring machine (TBM), the excavation efficiency of the equipment depends on the design of the cutter head, which is directly in contact with the ground. Especially, the allocation of disc cutter is crucial issue. Disc cutters can be divided into center cutter zone, inner cutter zone and transition cutter zone depending on where they are placed. Many studies have been conducted to identify optimal cutting conditions for face cutters. However, research to determine the optimal cutting conditions for the transition cutter has been relatively incomplete. In this study, to identify the optimal cutting conditions for the transition cutter, numerical analysis using discrete element method was performed, and the specific energy curve according to the angle between the transition cutters was drawn to find out the optimum cutting conditions. The results show that the angle between the transition cutters showing minimum specific energy in the transition cutter zone is 9°. Transition cutter zone was divided into three sections according to the slope angle of the transition cutter. It is also found that, the greater the slope angle of the transition cutter. This finding shows good agreement with the present design of transition cutter zone.

• Journal of Korean Society of Transportation
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• v.26 no.2
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• pp.57-67
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• 2008

Loading zone is necessary to central business district(CBD) due to freight trucks coming into inner city. Currently truck drivers in metropolitan area are forced to illegally park their freight trucks on the roads close to the business facilities because there is no or few loading zones available in the CBD. This situation would bring into traffic congestion and even might block local roads in the CBD. This study reviews the existing improvement plans in city logistics, and examines delivery characteristics related to freight trucks and drivers in Seomyeon, the central downtown of Busan. Also it conducts a location planning for on-street loading/unloading bay using a technical method for arranging loading space. This research estimated the number of parking and stop bays for truck's operation using queueing theory based on truck-service rate and arrival rate, and found locations with the minimum resistance function values for freight movement in arranging on-street loading/unloading bays.

• Journal of the Korean Society for Precision Engineering
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• v.2 no.3
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• pp.59-69
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• 1985

The purpose of this paper is to investigate the variations of out-of- roundness due to its assessment methods for the practical workpieces. Experiments were carried out with the test specimens having the typical roundness profile. The roundness measuring system which has the autocentripetal functions and the automatic centering table unit was used. From the experimental results, it was found that the ratio of LSC to MZC values varied with the shape of roundness profiles, and the rate of variation for out-of-roundness was increased logarithmically with the increment of undulations by the effect of filter. Therefore, it is suggested that the least squares center method should be useful with the sufficient accuracy except for some special cases in the roundness profiles, and the condition of filter has considerable influence upon the out-of-roundness to be measured.

• Fibers and Polymers
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• v.3 no.3
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• pp.120-127
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• 2002

Ever since the ideal forming theory has been developed for process design purposes, application has been limited to sheet forming and, for bulk forming, to two-dimensional steady flow. Here, application for the non-steady case was made under the plane-strain condition. In the ideal flow, material elements deform fellowing the minimum plastic work path (or mostly proportional true strain path) so that the ideal plane-strain flow can be effectively described using the two-dimensional orthogonal convective coordinate system. Besides kinematics, schemes to optimize preform shapes for a prescribed final part shape and also to define the evolution of shapes and frictionless boundary tractions were developed. Discussions include numerical calculations made for a real automotive part under forging.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4156-4162
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• 2013

This study was peformed to determine optimum induction heating conditions for a round bar of crankshaft. Four induction heating conditions were proposed and evaluated, employing numerical method, based on electromagnetic and sequential heat transfer analyses, resulting in optimum induction heating conditions which are finally proposed based on peak temperatures at heating zone and minimum temperature gradient through thickness of a round bar after 1 hour induction heating.

• The Korean Journal of Ecology
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• v.28 no.6
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• pp.395-404
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• 2005

A project has recently begun to reintroduce endangered Asiatic black bears to the Jirisan National Park. However, information on home range that is necessary to maintain the Minimum Viable Population (MVP) of those bears does not exist. Based on point data of two bears that were released for trial in Jirisan in 2001, we identified the movement pattern of bears and estimated their home ranges with two different methods Finally, the possibility of conserving the MVP of bears was evaluated by comparing the location and size of the home range with habitats which have been found to be suitable for bears. The frequency of bears' appearance reduced drastically as road densities of both paved roads and legal trails increased. The midpoint of home ranges of the two bears was 376.85 $km^2$ and 50.76 $km^2$ based on 100% MCP (Minimum Convex Polygon) and 95% AK (Adaptive Kernel Home Range Method), respectively, with an overlapped area of 126.0 $km^2$ and 3.99 $km^2$ each. The core areas of their home ranges are located not in the no-entry zone, where major trails were open to the public - despite being designated as no -entry zone - but in areas where most trails were closed to the public. A discrepancy between core areas of home ranges and potentially suitable habitats suggests the effects of vehicles and tracking people through roads within the park. Thus, for the success of in situ conservation of endangered bears, well-planned management of habitats is needed to protect bears and to ensure the home ranges to support the MVP.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.842-845
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• 2005

A method for the numerical simulation of two-dimensional free-surface flow resulting from the propagation of regular gravity waves over topography with arbitrary bottom shape is presented. The method is based on the numerical solution of the Euler equations subject to the fully nonlinear free-surface boundary conditions and the appropriate bottom, inflow and outflow conditions using a hybrid finite-differences and spectral-method scheme. The formulation includes a boundary-fitted transformation, and is suitable for extension to incorporate large-eddy simulation (LES) and large-wave simulation (LWS) terms for turbulence and breaking wave modeling, respectively. Results are presented for the simulation of the free-surface flow over two different bottom topographies, with constant slope values of 1:10 and 1:20, two different inflow wave lengths and two different inflow wave heights. An absorption outflow zone is utilized and the results indicate minimum wave reflection from the outflow boundary. Over the bottom slope, lengths of waves in the linear regime are modified according to linear theory dispersion, while wave heights remain more or less unchanged. For waves in the nonlinear regime, wave lengths are becoming shorter, while the free surface elevation deviates from its initial sinusoidal shape.