• Proceedings of the KSR Conference
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• 2009.05b
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• pp.201-206
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• 2009

In the testing stage of HEMU-400X(next Korean high speed train) developing project, maximum speed(400km/h) tests will be conducted. On present and near future conditions of the overhead contact lines, 400km/h is over the design speed criteria. The predictions of current collection performance including the percentage loss of contact(arcs level) parameter through dynamic interaction simulation of HEMU-400X maximum speed test run are described in this paper. Various simulations are conducted at the condition of two different contact wire tensions to draw the proper contact wire increasing values in the 400km/h test line under the available contact wire tension supporting condition of that line.

• Journal of Environmental Health Sciences
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• v.23 no.1
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• pp.18-27
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• 1997

The isolation, morphological study and growth characteristics of the algae were investigated from Lake Chuam. The isolated algae were applied the Agal Growth Potential test. The method of isolation and purification of the algae were used to Agar plating(AP), nutrient enrichment(NE), dilution(DI) and micro capillary technique(MC). Total isolated algae were 21 species. They were composed of Cyanophyceae, Dinophyceae, Bacillariophyceae, Euglenophyceae and Chlorophyceae. The numbers of algal strain by isolation technique were highest in dilution(21 species), and those of the rests were showed in order of NE > MC > AP. The sizes of isolated Selenastrum and Scenedesmus were $1.8\pm 1.4 \mu m$, $3.3\pm 0.9 \mu m$ in diameter and $6.4\pm 2.3 \mu m$, $13.6\pm 1.9 \mu m$ in length respectively. The morphology of isolated algae and NIES-collection strain was very similar each other, but the size was smaller isolated algae than that of NIES-collection. The optimum culture condition of isolated Selenastrum and Scenedesmus was about 30$\circ$C(25$\circ$C-35$\circ$C) in temperature and the maximum growth was appeared between 7,000 lux and 8,000 lux in the light intensity. The comparison of $\mu$(specific growth rate) on the concentration of nutrients such as nitrate and phosphate, isolated Selenastrum was appeared maximum it at 1.0 mg $NO_3-N/l$ but NIES-collection strain was showed 95% of maximum it at same nitrate concentration. Maximum g of isolated algae and NIES-collection strain in Scenedesmus onto nitrate concentration were very similar with the result of selenastrum. The specific growth rates of isolated algae and NIES-collection strain on the gradient concentration of phosphate were showed 0.72/day and 0.70/day at 0.02 mg $PO_4-P/l$ in Selenastrum but those of Scenedesmus were appeared 0.61/day and 0.57/day at same concentration $PO_4-P$.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.3
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• pp.272-280
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• 2011

A novel particle removal system for air handling unit (AHU) of subway station was evaluated experimentally. The novel system was designed in order to minimize the maintenance cost by applying axial-flow cyclones. The system consists of multiple cyclone units and dust trap. Based on our previous numerical study, it was found to be effective for removal $1\sim10{\mu}m$ sized dust particles. In this study, we manufactured the mock-up model and evaluated the model experimentally. Liquid and solid test particles were generated for evaluating collection efficiency of the system and the pressure drop was monitored. The collection efficiency was varied from 41.2% to 85.9% with increasing the sizes of particle from 1 to $6.5{\mu}m$ by particle count ratio of inlet and outlet. The pressure drop was maintained constant less than $20mmH_2O$. In addition, the collection efficiency was estimated by total mass for solid test particles. It was found that the collection efficiency was 65.7% by particle mass ratio of inlet and outlet. It shows that present system can replace current pre-filters used in subway HVAC system for removing particulate matters with minimal operational cost.

• Journal of Microbiology
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• v.34 no.3
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• pp.225-228
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• 1996

The cellular fatty acid methyl esters (FAMEs) analysis data obtained for clusters defined at a Euclidian distance of 17.5, in the classification of lactic acid bacteria isolated from kimchi, described by Lee et al. (4), was used for the identification of 79 Leuconostoc isolates. The test strains were isolated using a selective isolation medium specific for the genus Leuconostoc. These strains were then characterized according to their fatty acid profiles. The results show that all seventy nine test strains were identified to the known Leuconostoc clusters B, C, and D. Cluster B had the highest relative amount of the saturated fatty acid 16 : 0. The saturated fatty acid 16 : 0 and summed feature 9 were found as a major components in cluster C, which had a higher level of summed feature 9 than cluster B. Cluster D is characterized by the highest relative amount of the unsaturated fatty acid 18 : 1 w9c. It is suggested that FAMEs analysis can be successfully applied in the identification of lactic acid bacteria isolated from kimchi.

• Korean Journal of Medicinal Crop Science
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• v.26 no.3
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• pp.214-219
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• 2018

Background: This study was carried out to determine the best time for collecting ginseng berries without reducing the ginsenoside-Re content of ginseng roots, which are used as food, medicine, or cosmetic materials. Methods and Results: The test variety of ginseng used in this study was is Chunpung, which was collected from a 4-year-old ginseng field. Ginseng berries were collected at 7, 14, 21, 28, 35, 42, 49, and 56 days after flowering. The number of berry bunches per $1.62m^2$ ranged from 43.4 to 61.4, while the weight of berries per $1.62m^2$ was the greatest when they were collected 49 days after flowering. The root fresh weight per $1.62m^2$ was increased by 0.21 - 1.00 kg compared with that before the test, but root weight gain was decreased as the berry collection time was delayed. Total ginsenoside content of 4-year-old ginseng was the highest when berries were collected 7 days after flowering, while the ginsenoside-Re contents was the highest when collection was done 14 days after flowering. Conclusions: The most suitable period for ginseng berry collection was proposed to be from 14 to 21 days after flowering, as this is when the content of ginsenoside-Re, which is useful as a medicinal or cosmetic material, is still high and the ginseng root has not yet decreased in weight.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.4732-4737
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• 2011

A standing grinder with a vacuum dust collection, which works grinding a surface and collecting dust occurred simultaneously, is needed to clean the surface before painting, or to remove a weld bead burr in the industrial field. In recent it trends to be compact and potable with high grinding and dust collection power, and low noise. As increasing these grinding and dust collection power, the noise and weight of standing grinder occurs an important problem. To solve these problem, an efficient cyclone separator was designed and developed by Ansys-CFX analysis and experiments. A weight of the developed grinder part was 5.9kg, which can be easily handled on standing by workers. and a noise level of the developed prototype was measured 69.9 dB(A).

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.20 no.2
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• pp.31-44
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• 2009

The conspectus, based on a set number of subject descriptors derived essentially from LC subject classifications, provides a consistent framework within which libraries could report subject intensity. While library collection development has been benefitted by using this conspectus, its effectiveness in this digital era is under controversy. The purpose of this study is to survey the concepts and the various types of conspectus in library collection development and to test the applicability of a revised conspectus model to electronic resource management in libraries. For this, the focus was especially put on investigating the characteristics of electronic resources as considered the collection depth usually identified in collection development policies. Previous research has been also surveyed to consolidate their outcomes in order to design a matrix model of conspectus, which put the characteristics, persistence, and collection level in consideration in oder for the design of the conspectus model.

• Journal of the Korean Society for Library and Information Science
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• v.15
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• pp.175-195
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• 1988

Use studies of library collections have been conducted as a method of evaluating collections in a library. The main purpose of use studies is to evaluate the quality of a library collection in terms of extent and mode of its use. In addition to use studies, both quantitative and qualitative methods could be utilized in order to evaluate a library collection. However, the quantitative and qualitative collection evaluation methods are more concerned with the collection itself than with its use. Use studies have been conducted in large academic libraries for the following specific purposes: 1) They attempt to identify little used portion of collections that can be retired less accessible and less expensive storage area. 2) They try to identify core collections to satisfy some degree of circulation demands in the near future. 3) They try to identify use patterns of selected subject areas or type of books that can be used to adjusting collection development practices or fund allocations. 4) They try to assess the document delivery capability of a library to improve their availability. A number of methodologies employed for these specific purposes fall into four major categories; 1) circulation analysis method, 2) last circulation method, 3) relative use method, and 4) document delivery test. Each method is briefly reviewed with its limitations.

• Journal of the Korean Society of Safety
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• v.17 no.4
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• pp.25-30
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• 2002

This paper demonstrates the effects of dust electrical resistivity on electrostatic precipitability. The effects of gas temperature, velocity and humidity on the collection efficency were considered by used of coal fly ashes from fluidized bed combustion boiler. The experiments for collection efficiency were carried out in the pilot plant. The ashes which have non-spherical geometry and high electrical resistivity were used. Electrical resistivity is an important property for the collection efficiency in the electrostatic precipitators. Fly ash resistivity as a function of temperature up $350{\circ}C$ and water concentration(up to 15%) has been experimentally investigated using the resistivity test equipment consisted of the movable electrode, dust cup, and furnace. As the resistivity of fly ash in the operating temperature($150{\circ}C$) of an electrostatic precipitator was measured higher than $1010{\Omega}{\cdot}$cm, flue gas conditioning in the electrostatic precipitator to reduce the resistivity of fly ash is required.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.6
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• pp.975-980
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• 2017

Overhead catenary system of electric railway has overlap sections which devide and tighten trolley wire supplying electric power to train, where current collection performances may become worse according to railway speed-up. Current collection tests conducted at 400 km/h test-bed section of Honam high-speed railway show that balanced line arrangement at overlap section is needed to secure current collection without arc generation between trolley wire and train current collection device. This paper proposes a design procedure of the overlap section to allow for tension increase and uplift of the trolley wires according to railway speed-up. By applying the proposed procedure to the overhead catenary system of Honam high-speed railway, it is suggested that the minimum span length should be 33.2 m for railway speed-up to 350 km/h and 43.7 m for speed-up to 400 km/h.