• Mycobiology
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• v.51 no.5
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• pp.288-299
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• 2023

Aspergillus is one of the largest and diverse genera of fungi with huge economical, biotechnological, and social significance. Taxonomically, Aspergillus is divided into six subgenera comprising 27 sections. In this study, 235 strains of Aspergillus subgenus Circumdati (section: Candidi, Circumdati, Flavi, Flavipedes, Nigri, and Terrei) preserved at the Korean Agricultural Culture Collection (KACC) were analyzed and re-identified using a combined dataset of partial b-tubulin (BenA), Calmodulin (CaM) gene sequences and morphological data. We confirmed nineteen species to be priorly reported in Korea (A. neotritici, A. terreus, A. floccosus, A. allahabadii, A. steynii, A. westerdijkiae, A. ochraceus, A. ostianus, A. sclerotiorum, A. luchuensis, A. tubingensis, A. niger, A. welwitschiae, A. japonicus, A. nomius, A. tamarii, A. parasiticus, A. flavi, and A. oryzae). Among the studied strains, three species (A. subalbidus, A. iizukae, and A. uvarum), previously unreported or not officially documented, were discovered in Korea, to the best of our knowledge. We have given a detailed description of the characteristic features of the three species, which remain uncharted in Korea.

• Advances in environmental research
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• v.5 no.3
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• pp.201-211
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• 2016

Laboratory tests were conducted to evaluate the performance of waste rubber shreds in leachate collection layer of engineered landfills. The study found that waste rubber shreds layer in combination with a gravel layer can be of potential use in landfill drainage system. To study the performance, conventional gravel along with waste rubber shreds were used in different combinations (with total layer thickness = 500 mm) as leachate collection media. For the laboratory study poly vinyl chloride (PVC) pipes were used. The size range of waste rubber shreds used were 25 mm to 75 mm in length and width = 10 to 20 mm. The gravel size used in the leachate collection media is 10 mm to 20 mm size. Performance study of 7 Test Cols. with different combinations of waste rubber shreds and gravel bed thickness were studied to find out the best combination. The study found that the Test Col.-3 having waste rubber shreds thickness = 200 mm and gravel layer thickness = 300 mm gave the best results in terms of percentage removal in various physicochemical parameters present in the leachate. Further to find the best size rubber shreds three more Test Cols - 8, 9 and 10 were constructed having the rubber shreds and gravel layer ratio same as that of Test Col.-3 but having rubber shreds width = 10 mm, 15 mm and 20 mm respectively. Based on the results obtained using Test Cols. 8, 9 and 10 the study found that smaller size rubber shreds gave bests results in terms of improvement in various leachate parameters.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.3
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• pp.217-226
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• 2009

This study was carried out to investigate the effects of collection time on the physical characteristics, Nutritive value, digestibility and palatability in rice straw. Collection time of rice straw after the rice harvest was allocated into nine treatments: T1 (10 days), T2 (25 days), T3 (40 days), T4 (55 days), T5 (70 days), T6 (85 days), T7 (100 days), T8 (115 days) and T9 (130 days). The results are summarized as follow: Plant length, leaf length and green degree were decreased with prolonging collection time. Mold distribution and dry matter loss were increased with prolonging collection time. Crude protein and crude fat were decreased with prolonging collection time, crude fiber were increased with prolonging collection time. But crude ash showed multifarious. In situ dry matter digestibility was decreased with prolonging collection time. Palatability of Hanwoo, Holstein and deer was decreased with prolonging collection time. The results of this study indicate that good rice straw collection time would be recommendable during the from 10 days to 40 days after rice straw harvest.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.1
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• pp.84-89
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• 1997

Recentely, a compact and small size air-cleaning Electrostatic Precipitator(ESP) is needed to develop for air conditioning devices. From Deutsch formula for ESP efficiency, collection efficiency is affected not only the structure of collection section but also the charge rate of dust. In terms of collection area, the most useful type is a scroll type ESP. In this work, we investigated experimentally aptimum design factor of scroll type ESP by application of Taguchi method. And we developed the scroll type ESP by using optimal condition of control factor.

• 연구논문집
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• s.34
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• pp.21-28
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• 2004

In this study, we report an investigation for the charging and collection of aerosol nanoparticles in an electrostatic precipitator (ESP) according to particle charging and diffusion effects. The competition between charging probability and diffusion effect determines the collection efficiency of nanoparticles in the ESP. In conclusion, collection efficiency continuously decreased with the reduction in the particle size. This indicates that poor partial charging effect of nanoparticles is more dominant than their diffusion effect in the ESP for the nanoparticles in the particle size range of 4-20 nm. Theoretical calculations using a unipolar diffusion charing theory were in good agreement with the experimental data for the nanoparticles less than 20 nm in diameter.

• Advances in Computational Design
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• v.5 no.3
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• pp.261-276
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• 2020

The reasonable layout of vacuum cleaner can effectively improve the collection efficiency of iron filings generated in the process of steel production. Therefore, in this study, the CFD-DEM coupling model and two-fluid model are used to calculate the iron filings collection efficiency of vacuum cleaner with different inclination/cross-sectional area, pressure drop and inlet angle. The results are as follows: The CFD-DEM coupling method can truly reflect the motion mode of iron filings in pneumatic conveying. Considering the instability and the decline of the growth rate of iron filings collection efficiency caused by high pressure drop, the layout of 75° inclination is suggested, and the optimal pressure drop is 100Pa. The optimal simulation results based on two-fluid model show that when the inlet angle and pressure drop are in the range of 45°~65° and 70Pa~100Pa, larger mass flow rate of iron filings can be obtained. It is hoped that the simulation results can offer some suggestion to the layout of vacuum cleaner in the rolling mill.

• Particle and aerosol research
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• v.8 no.1
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• pp.1-8
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• 2012

In this study, the collection efficiency of inertial impactors was numerically simulated by employing the statistical Lagrangian particle tracking(SLPT) model. The SLPT model was proven to be correct in predicting the impactor collection efficiency, when the numerically obtained collection efficiencies were compared with the experimental data of Marple et al.(1987) at normal pressure level and the experimental data of $Marjam{\ddot{a}}ki$ et al.(2000) at low pressure level. Based on the validation results, balloon-borne impactors with the cut-off sizes of $1{\mu}m$, $2.5{\mu}m$, and $10{\mu}m$ were designed. Then, the sampling flowrates of the inertial impactors, required to keep the cut-off sizes constant at different pressures and temperatures, were estimated according to the altitude.

• International Journal of Safety
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• v.4 no.1
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• pp.18-22
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• 2005

A model was proposed for investigating the particle removal from suspension with particles of different sizes by deep-bed filtration, and the collection efficiency was predicted by computer simulation. Deposited particles on the pore surface may act as additional collector and reduce the pore size, which contribute to the improved collection efficiency with increase of deposition. Computer experiments for suspension of particles of three sizes and its equivalent size of mono particles were carried out and compared. The collection efficiency of suspension with poly-dispersed particles shows higher efficiency than that of suspension with mono-dispersed particles. Also the collection efficiency of smell particle of mixture is higher that that of same uniform size particles.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.2
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• pp.179-190
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• 2000

The main object of this study was to investigate experimentally the characteristics of electrostatic cyclone-bag filter with upper tangential inlet in order to overcome the low collection efficiency for the submicron particle and high pressure drop which were main problems of general fabric bag filters. The experiment was carried out for the analysis of collection efficiency and pressure drop of electrostatic cyclone-bag filter comparing to those of fabric bag filter with various experimental parameters such as the inlet velocity(filtration velocity) and applied voltage etc. In the results the upper tangential inlet type showed higher collection efficiency for submicron particles below 2 ${\mu}{\textrm}{m}$ in diameter than that of center inlet and over 99.9% for overall collection efficiency. Pressure drop reduction ratios were shown as 40-50% for the applied voltage 0kV by centrifugal force and 70-90% for 20k V by the centrifuga and electrostatic force with the tangential inlet velocity (12-21m/s)

• Journal of Information Management
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• v.24 no.3
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• pp.57-72
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• 1993

The purpose of this study is to investigate the present status of foreign academic journal collection in Korea and to explore the problem. In order to survey the current situation, the data from "Union Catalogue of Foreign Journals:Science & Technology, 1992" database constructed by Korea Institute of Industry and Technology Information has been analyzed. Major problems are poor collections, collection overlap, and lack of resource sharing.