• Journal of Radiation Industry
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• v.11 no.3
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• pp.157-165
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• 2017

In this paper, we calculate the light photons collection efficiency of large-volume plastic scintillation detector mainly used for radiation portal monitor (RPM). A Monte Carlo light photon transport code, DETECT2000, were used to quantitatively evaluate light collection efficiency of plastic scintillation detector. DETECT2000 calculated the placement of light collection efficiency based on the energy spectrum. We calculated the light collection efficiency relative to the position of the energy spectrum that proportional to the placement of the source. The $850{\times}285{\times}65mm^3$ size of polyvinyl toluene (PVT) scintillator was used for measurements. Through DETECT2000 simulation, the light collection efficiency of $5{\times}5$ arrays were calculated and verification was performed by comparing with experimentally measured. And then, the corrected MCNP simulation by applying the light collection efficiency in $21{\times}13$ arrays was compared and analyzed. Comparing the Monte Carlo simulation with measured results, it shows an average difference of 10.1% in $5{\times}5$ arrays. Particularly, about twice of the difference was found in the edge of first column, which coupled with PMT. In whole $5{\times}5$ array, the overall ratio was the same except for the first column. And then comparing the energy spectra of the $21{\times}13$ array with and without the light collection efficiency, it shows a difference of 6.69% in Compton edge area. The DETECT2000 based light collection efficiency simulation showed well agreement with the point source experiment. And comparing with measured energy spectra, we could compare the differences according to whether or not the light collection efficiency was applied. As a results, it is possible to increase the accuracy and reliability of Monte Carlo simulation results by pre-calculating the light collection efficiency according to the PVT geometry by using the DETECT2000.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.16 no.2
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• pp.203-224
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• 2005

The purpose of this study is to provide guidelines of library collection development policies statements. As a case study, 5 national and 2 public libraries are selected and analyzed by using 10 elements, which were drawn from existing studies, for examining collection development policy statements. The results show several suggestions which may help the people who is interested in preparing collection development policy statements.

• Journal of Korean Society of Archives and Records Management
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• v.5 no.1
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• pp.23-46
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• 2005

This study examines the collection policy of University Archives. The establishment of collection policy enables university archives to concentrate in which memories of university to remain and provide as archives. Accordingly, this study, making a model of university archives in early sage of establishment, intends to investigate the collection policy for collecting archives in university. The first chapter defines the fields and categories of collection of archives. In order to define the collection categories, it outlines the history of the university and set up the fields and categories for documentation. In the second chapter, this study examines about the factors which forms the document of the collection policy, such as a missions statement, a guide to collection, and a guide to acceptance by items. Then, this study, applying items mentioned above, suggests a plan for a collection policy. The model presented in this study may not represent the model of collection policy in the university archives. However, it is meaningful as a study of collection policy and has purpose and significance in making a stepping stone for more developmental collection policy.

• The Korean Journal of Archival Studies
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• no.48
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• pp.5-44
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• 2016

This paper examines the characteristics of the May 18th (5 18) Gwangju Democratization Movement archives to suggest a collection development strategy for the May 18th archives collection network. Individual public and civilian archives collecting the May 18th archives separately should form a cooperative collection network based on documentation strategy. Most of all, May 18th archives are human rights records and should be understood and collected as human rights records. International principles support the collection of the May 18th archives as human rights archives by prohibiting destruction of relevant temporary records and encouraging the victims' right to access to their records. As the May 18th archives were mostly produced by many multiple agencies, this multi-provenance and diversity of the records necessitate the building of an archives portal for the records registries and online search. To document the undocumented past and the victims, the collection network should focus on oral history project as a major part of its collection development strategy. Finally, the May 18th archives collection network should build a cooperative relations with the unwilling public agencies which have the archives holdings. Therefore, the collection development strategy should include advocacy and awareness activities for promoting cooperation from these public agencies and public archives, and the people in general.

• Journal of Korean Library and Information Science Society
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• v.44 no.1
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• pp.409-432
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• 2013

The purpose of this study is to examine 5 writing guidelines of reference collection development policy(RCDP) and to identify major elements of RCDP through the comparison and analysis of 24 RCDP in academic libraries in the U.S. As a result of this study, a total of 9 elements(5 core elements and 4 selective elements) were identified. Five core elements were (1) introduction, (2) scope, size, and level, (3) format, (4) types, and (5) management(i.e., selection, weeding, evaluation, and responsibilities) of reference collection. The results of this study would be helpful to those academic libraries which are planning to write RCDP in academic libraries in the near future.

• Nuclear Engineering and Technology
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• v.41 no.5
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• pp.723-728
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• 2009

The response property of the CZT detector ($5{\times}5{\times}5\;mm^3$), widely used in photon spectroscopy, was evaluated by considering the charge collection efficiency, which depends on the interaction position of incident radiation, A quantitative analysis of the energy spectra obtained from the CZT detector was also performed to investigate the tail effect at the low energy side of the full energy peak. The collection efficiency of electrons and holes to the two electrodes (i.e., cathode and anode) was calculated from the Hecht equation, and radiation transport analysis was performed by two Monte Carlo codes, Geant4 and MCNPX. The radiation source was assumed to be 59.5 keV gamma rays emitted from a $^{241}Am$ source into the cathode surface of this detector, and the detector was assumed to be biased to 500 V between the two electrodes. Through the comparison of the results between the Geant4 calculation considering the charge collection efficiency and the ideal case from MCNPX, an pronounced difference of 4 keV was found in the full energy peak position. The tail effect at the low energy side of the full energy peak was confirmed to be caused by the collection efficiency of electrons and holes. In more detail, it was shown that the tail height caused by the charge collection efficiency went up to 1000 times the pulse height in the same energy bin at the calculation without considering the charge collection efficiency. It is, therefore, apparent that research considering the charge collection efficiency is necessary in order to properly analyze the characteristics of CZT detectors.

• Korean Journal of Microbiology
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• v.55 no.3
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• pp.296-299
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• 2019

The genus of Bacteroides has been isolated from vertebrate animal feces. Bacteroides sp. KGMB 02408 was isolated from fecal samples obtained from a healthy Korean. The wholegenome sequence of Bacteroides sp. KGMB 02408 was analyzed using the PacBio Sequel platform. The genome comprises a 5,771,427 bp chromosome with a G + C content of 39.50%, 5,005 total genes, 18 rRNA genes, and 74 tRNA genes. Furthermore, we found that strain KGMB 02408 had some genes for oxidoreductases and menaquinone biosynthesis in its genome based on the result of genome analysis.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.1
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• pp.66-72
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• 2004

In this study, quantity and quality of collected rainwater by sand, gravel, soil, lawn and concrete surface, as collection materials were investigated and Rainwater Collection Prediction Model was developed to predict the amount of collected rainwater. The quantity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 1,067L(93.2%), 1,006L(87.8%), 902L(78.8%), 800L(69.9%), 788.5L(68.8%) for 8 months period, respectively. The average turbidity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 3.2NTU, 2.2NTU, 1.9NTU, 1.7NTU, 1.5NTU for 8 months period, respectively. For sand collection material, predicted amount by the Model and actual collected amount were 931.5L and 902L, which were very closed. For gravel collection material, predicted amount by Model and actual collected amount were 1,028.21. and 1,006L, which were very closed. To simulate the optimal rainwater storage volume, the rainfall and evaporation data in Dae-jeon city were used. For sand collection system with 30m2 area, the maximum storage volume was $17m^3$ and 62% of the year was secured for use of 240L/day.

• Journal of the Korean Society of Visualization
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• v.18 no.3
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• pp.77-83
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• 2020

A uniflow cyclone has simple structure with a single channel in one direction. The one directional particle removal enables the uniflow cyclone to have compact size and low pressure drop. However, it has low collection efficiency compared to conventional cyclones. In this study, the effect of primary geometry on the performance of a uniflow cyclone with swirl vane is numerically investigated for the design of high performance uniflow cyclone. It is found that as the vortex finder diameter is increased, the pressure drop and the collection efficiency are decreased. Also, the same trend is predicted when the vortex finder height is increased. The best collection efficiency is predicted to be obtained when the vortex finder height is equal to the diameter of a cyclone. Reducing the body height by half will increase the pressure drop by 41%. When the body height is decreased, the collection efficiency is first increased and then decreased. The best collection efficiency is obtained when the body height is 4~5 times the cyclone diameter. Overall, the particle collection efficiency is highest when the Dν/D is equal to 0.3. But, the pressure drop is as high as 1592 Pa. Considering both collection efficiency and pressure drop, the best design is when Dν/D, Hν/D, and Hb/D are equal to 0.5, 1, and 5, respectively.

• Korean Journal of Remote Sensing
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• v.30 no.5
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• pp.571-586
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• 2014

Moderate Resolution Imaging Spectroradiometer (MODIS) provides air temperature (Tair) and dew point temperature (Tdew) profiles at a spatial resolution of 5 km. New Collection 6 (C006) MODIS07_L2 atmospheric profile product has been produced since 2012. The Collection 6 algorithm has several modifications from the previous Collection 5 (C005) algorithm. This study evaluated reliabilities of two alternative datasets of surface-level Tair and Tdew derived from C005 and C006 Aqua MODIS07_L2 (MYD07_L2) products using ground measured temperatures from 77 National Weather Stations (NWS). Saturated and actual vapor pressures were calculated using MYD07_L2 Tair and Tdew. The C006 Tair showed lower mean error (ME, -0.76 K) and root mean square error (RMSE, 3.34 K) than the C005 Tair (ME = -1.89 K, RMSE = 4.06 K). In contrasts, ME and RMSE of C006 Tdew were higher than those (ME = -0.39 K, RMSE = 5.65 K) of C005 product. Application of ambient lapse rate for Tair showed appreciable improvements of estimation accuracy for both of C005 and C006, though this modification slightly increased errors in C006 Tdew. The C006 products provided better estimation of vapor pressure datasets than the C005-derived vapor pressure. Our results indicate that, except for Tdew, C006 MYD07_L2 product showed better reliability for the region of South Korea than the C005 products.