• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.1
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• pp.67-75
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• 2005

The size and main ingredient of hot particulate generated during the nuclide experiment in hot cells of nuclear facilities were 0.5300 $\mu$m and UO$\_2$. A cyclone filter equipment which consists of a cyclone and Bag/HEPA filter was devised to remove hot particulate generated during the nuclide experiment in hot cells of nuclear facilities. The experimental conditions to maximize the collection efficiency of hot particulate were suggested through experiments done with the cyclone filter equipment. With the large size of simulated particulate, the collection efficiency of the particulate was high. When the size of simulated particulate was more than 5 $\mu$m, the collection efficiency of the particulate was more than $80\%$ and when the size of simulated particulate was less than 1.0 urn, the collection efficiency decreased by less than $70\%$. If the inflow velocity of simulated particulate was increased, the collection efficiency of the particulate was also increased. When the inflow velocity of simulated particulate was more than 12m/sec, the collection efficiency was higher than $70\%$, but after 17 m/sec inflow velocity, no change observed. The collection efficiency of the simulated particulate can be enhanced with the length of vortex finder inside the chamber. With the length of vortex finder, 7.2cm, the observed collection efficiency of the particulate was the maximum. Moreover, when the sub-cone was attached under the cyclone, the collection efficiency of cyclone increased $2\%$. It was found that effect by attachment of sub-cone was not serious.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.1
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• pp.143-148
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• 2012

This study evaluated the quality characteristics of white birch (Betula platyphylla var. japonica) sap with different collection times. The changes of browning index, turbidity, pH, total acidity, organic acid, free sugar, crude protein, crude ash, and mineral content were investigated. The browning index and turbidity increased from 0.076 to 0.222 and from 0.048 to 0.138, respectively, with increasing collection time. The pH decreased from 6.09 to 4.72, while total acidity increased with increasing collection time. Citric and malic acids were detected and malic acid increased with increasing collection time. Glucose and fructose as free sugars were detected and their contents were 0.364~0.433% and 0.497~0.664%, respectively. Crude protein and crude ash contents remarkably increased from 3.40 to 32.37 mg% and from 0.01% to 0.04%, respectively, with increasing collection time. Cu, Fe, Ca, Mg, Mn, and K were detected, and increased with increasing collection time. Particularly, K increased remarkably from 5.25 to 37.27 mg/L over time. These results indicate that the optimum processing method to improve the quality of white birch sap is necessary, because the quality of sap decreased as collection time increased, but nutritional value increased.

• Journal of Digital Convergence
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• v.9 no.5
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• pp.31-43
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• 2011

Since the R&D Program for Small and Medium-sized Enterprises started in 1997 as a part of Small and Medium Business Administration, many companies succeeded to carry out the tasks and were charged royalty fees from the government aid program in return. However, some of them were unable to pay a royalty because of their poor financial positions. Failure to pay a royalty also led to adding administrative duties including debt collection and imposing a penalty of participation restriction for other R&D programs. To solve the problems incurred by a failure of royalty collection, a divided payment using a surety insurance was introduced in 2009. That is, the R&D program recipients who were charged royalties issue surety insurance policies and submit them to a collection agency with a plan of divided payment. In this study, we estimate the main benefits of introducing surety insurance for royalty collection. First, we analyze royalty collection results from recipients supported by the R&D program from 1997 to 2006. By doing so, we calculate the main parameters that will be used for estimating the 2011 collection results. Next, besides estimating the quantitative effect, which summarizes an increase of royalty collection via surety insurance, we also analyze various qualitative effects such as simplification of the collection process and expansion of opportunities for participation in R&D programs.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.3
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• pp.297-306
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• 2003

Works were focused on back pressure characteristics of ceramic fiber filter on DPF (Diesel Particulate Filter) system and experiments were performed to select appropriate filter which can filter particulates. Filters were installed on metal -support tube which has openings for exhaust gas flow. Ceramic fiber filters with high specific surface area and adequate high temperature strength are commercially available for filtration of diesel particulates and in -situ hot regeneration. Thus, ceramic blanket and ceramic board which are used as insulating media were applied to filter and filtration apparatus was installed on exhaust gas line connected to 2.0 L diesel engine. Alternating filter structure to adapt DPF system, collection efficiency test of diesel particulates was measured. In case of ceramic blanket, pressure drop was low, caused by the destruction of soft structures. Also, particulate collection efficiency was decreased depending on loading time. In case of ceramic board, structure design was altered to reduce back pressure on DPF system. Structure design was altered to induce Z-flow by making 10 mm and 5 mm holes on the surface of media. Alteration of 5 mm hole showed that media have low back pressure but particulate collection efficiency was 77%, while 10 mm hole showed that of 90%.

• Journal of Microbiology and Biotechnology
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• v.24 no.12
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• pp.1606-1608
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• 2014

During an investigation of the fungal diversity of Korean soils, four Penicillium strains could not be assigned to any described species. The strains formed monoverticillate conidiophores with occasionally a divaricate branch. The conidia were smooth or finely rough-walled, globose to broadly ellipsoidal and $2.5-3.5{\times}2.0-3.0{\mu}m$ size. Their taxonomic novelty was determined using partial ${\beta}$-tubulin gene sequences and the ribosomal internal transcribed spacer region. The phylogenetic analysis showed that the isolates belonged to section Lanata-Divaricata and were most closely related to Penicillium raperi. Phenotypically, the strains differed from P. raperi in having longer and thicker stipes and thicker phialides. Strain KACC $47721^T$ from bamboo field soil was designated as the type strain of the new species, and the species was named Penicillium koreense sp. nov., as it was isolated from various regions 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.

• Advances in environmental research
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• v.5 no.4
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• pp.237-249
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• 2016

The management of municipal solid waste (MSW) is essential for every community; and, it is currently a major challenge in Nigeria. This paper provides an overview of the current MSW management trends in Nigeria and proposes new sustainable MSW management systems. Across Nigerian cities, MSW management is characterized by inefficient collection and transportation to disposal sites. Collection services do not reach some unplanned areas and slums due to poor street network. Even some planned areas are not reached by collection services. The informal sector contributes to waste collection, resource recovery and recycling; however, their activities are not recognized by the governments. Markets exist for recovered materials but more efforts need to be geared towards intensive recovery of materials and expansion of these markets. Despite the high proportion of putrescible matter in MSW, the only form of treatment commonly used currently is open burning for volume reduction. The high organic fraction presents a great opportunity for composting and anaerobic digestion. Ultimate disposal is currently done in open dumpsites. This needs to be upgraded to engineered landfills that are properly sited and adequately operated by well trained personnel. There is an emerging waste stream of concern, electronic-waste (e-waste), that requires urgent sustainable management as e-waste are currently co-disposed with other waste streams or burnt in the open posing detrimental health impacts.

• Journal of Microbiology and Biotechnology
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• v.24 no.3
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• pp.334-336
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• 2014

A new species named Aspergillus cumulatus sp. nov. is described in Aspergillus section Aspergillus (Eurotium state). The type strain (KACC $47316^T$) of this species was isolated from rice straw used in meju fermentations in Korea, and other strains were isolated from the air in a meju fermentation room. The species is characterized by growth at a wide range of water activities and the formation of aerial hyphae on malt extract 60% sucrose agar (ME60S) that resemble a cumulus cloud. Furthermore, A. cumulatus produces yellow ascomata containing small lenticular ascospores (5.1-5.7 ${\mu}m$) with a wide furrow, low equatorial crests, and tuberculate convex surface. The species is phylogenetically distinct from the other reported Aspergillus section Aspergillus species based on multilocus sequence typing using rDNA-ITS, ${\beta}$-tubulin, calmodulin, and RNA polymerase II genes.

• Particle and aerosol research
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• v.19 no.3
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• pp.89-100
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• 2023

In our previous study, a wire-plate type electrostatic precipitator (ESP) was developed to collect bioaerosols of 100 nm size. In the study, various flow rates (40 ~ 100 L/min) and applied voltages (3 ~ 10 kV) were tested for experiment. In this study, numerical analysis was performed for the ESP of the previous study with the same flow rates and applied voltages, but with varying the size of bioaerosols to 0.04 ~ 2.5 ㎛. Overall, the numerical analysis results well predicted the experimental data. Bioaerosols of 0.1 ~ 0.5 ㎛ showed the minimum collection efficiency for all conditions because of low charge number. The effect of the ionic wind generated by the corona discharge was calculated. However, the ionic wind did not affect much the collection efficiency. The aerosol collection in the ESP of this study was due to the electrostatic force generated by particle charge in the electric field. This numerical study on the ESP can be used for the design and optimization of higher flow rate (> 100 L/min) ESP.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.5
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• pp.428-432
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• 2012

In the waste collection system, living waste is collected through the piping network. There are many confluent pipes in a piping network. These confluent pipes were often clogged up with waste. The optimal configuration of the confluent pipes has been defined by the design guide. However, nobody know how this design guide were determined. Therefore, in this paper, we found the design data for the confluent pipe configuration in order to avoid the waste clogging in a piping network. The distance between connected point on the confluent pipes should be longer than the previous design guide.