• Korean Journal of Plant Tissue Culture
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• v.28 no.3
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• pp.153-157
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• 2001

Protoplasts were isolated from hypocotyls, cotyledons, and young leaves of Chinese cabbage grown under in vitro environmental condition. An enzyme mixture of 1% Cellulysin and 0.5% Macerozyme in combination with 0.4 M mannitol was most effective condition for protoplast isolation. The highest yield of protoplasts, 7.6$\times$10$^{5}$ protoplast/g of fresh weight, was obtained from the treatment of leaves for 12~16 hours at 27~28$^{\circ}C$ with shaking at 30 rpm. The most suitable medium for an initial cell division was K8p basal medium supplemented with 5 mg/L 2,4-D and 2 mg/L kinetin. Within 7~10 days, protoplasts derived from hypocotyl and cotyledon tissues formed cell colonies. When the cells were grown at the size of 8~10 cells, they were embedded into semi-solid medium containing 0.2% agarose. Calli derived from protoplast culture were transferred to the 100 different types of plant regeneration media, but no completely regenerated plants from inbred lines of Chinese cabbage used for this study wore obtained, though frequent rooting took place in several media tested.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.423-431
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• 2014

Supply of rural community sewage treatment plant (RCSTP) is need for protect of water quality like water source and development of agriculture areas. In this study conducted analysis on characteristics of RCSTP sewage and treatment efficiency of installed treatment process using operation results of RCSTP in an-dong area. high organic matter and nutrient were contained in RCSTP sewage of an-dong than urban area. RCSTP treatment process in an-dong was shown stable treatment efficiency. But nutrient treatment efficiency was shown more sensitive result about SRT and F/M ratio than organic matter treatment efficiency. And RCSTP treatment process in an-dong was shown higher treatment efficiency than other treatment proces like $A^2/O$, SBR and media. Thus, this process is effective treatment process for application of RCSTP.

• KIISE Transactions on Computing Practices
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• v.21 no.10
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• pp.639-644
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• 2015

The capacity of flash-based storage such as Solid State Drive(SSD) and embedded Multi Media Card(eMMC) is ever-increasing because of the needs from the end-users. However, if a flash-based storage crashes, such as during power failure, the flash translation layer(FTL) is responsible for the crash recovery based on the entire flash memory. The recovery time increases as the capacity of the flash-based storages increases. We propose O1FTL with O(1) crash recovery time that is independent of the flash capacity. O1FTL adopts the working area technique suggested for the flash file system and evaluates the design on a real hardware platform. The results show that O1FTL achieves a crash recovery time that is independent of the capacity and the overhead, in terms of I/O performance, and achieves a low P/E cycle.

• Smart Media Journal
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• v.6 no.3
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• pp.15-20
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• 2017

Recently, the automotive industry has been studied about driver assistance systems for helping drivers to drive their cars easily by integrating them with the IT technology. This study suggests a method of detecting lanes, robust to road condition changes and applicable to lane departure warning and autonomous vehicles mode. The proposed method uses the method of detecting candidate areas by using the Gaussian filter and by determining the Otsu threshold value and edge. Moreover, the proposed method uses lane gradient and width information through the Hough transform to detect lanes. The method uses road lane information detected before to detect dashed lines as well as solid lines, calculates routes in which the lanes will be located in the next frame to draw virtual lanes. The proposed algorithm was identified to be able to detect lanes in both dashed- and solid-line situations, and implement real-time processing where applied to Raspberry Pi 2 which is open source hardware.

• 한국균학회소식:학술대회논문집
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• 2015.11a
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• pp.16-16
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• 2015

Ectomycorrhizal (ECM) mushrooms play a major role in plant growth promotion through symbiotic association with roots of forest trees. They also provide an economically important food resource to us and therefore they have been studied for their artificial cultivation for decades in Korea. We have secured bio-resources of ECM mushrooms from Korean forests and performed their physiological studies. To investigate the cultural characteristics, the fungi were cultured under different conditions (medium, temperature, pH of the medium, inorganic nitrogen source). More than 90% of total 160 strains grew on three solid media (potato dextrose agar, PDA; sabouraud dextrose agar, SDA; modified Melin-Norkrans medium, MMN). The rate of mycelial growth on malt extract agar (MEA) was lower than those of three media (PDA, SDA, MMN). None of the Tricholomataceae strains grew on MEA. Many strains of ECM mushrooms were able to grow at the temperature range of $15{\sim}25^{\circ}C$ on PDA, while they showed poor growth at $10^{\circ}C$ or $30^{\circ}C$. In particular, the growth rates of both Gomphaceae and Tricholomataceae were significantly lower at $10^{\circ}C$ than at $30^{\circ}C$. The optimal pH of many strains was pH 5.0 when they cultured in potato dextrose broth (PDB). Fifty-seven percent of tested strains grew well on medium containing ammonium source than nitrate source. Many strains of Tricholomataceae showed a notable growth on ammonium medium than nitrate medium. Twenty-three percent of strains preferred nitrate source than ammonium source for their mycelial growth. The production and activity of two enzymes (cellulase and laccase) by ECM fungi were also assayed on the enzyme screening media containing CMC or ABTS. Each strains exhibited different levels of enzymatic activities as well as enzyme production. The number of laccase-producing strains was less than that of cellulase-producing strains. We found that 77% of tested strains produced both cellulase and laccase, whereas 2% of strains did not produce any enzymes. The morphological characteristics of mycelial colony were also examined on four different solid media. Yellow was a dominant color in mycelial colony and followed by white and brown on all culture media. ECM mushrooms formed mycelial colonies with a single or multiple colors within a culture medium depending on the strains and culture media. The most common shape of mycelial colony was a circular form on all media tested. Other families except for Amanitaceae formed an irregular colony on MMN than PDA. All strains of Tricholomataceae did not form a filamentous colony on all media. The pigmentation of culture media by mycelial colonies was observed in more than 50% of strains tested on both PDA and SDA. The degree of pigmentation on PDA or SDA was higher than MMN and brown color was dominant than yellow color. The production of exudates from mycelial colony was higher on PDA than MMN. Brown exudates were mainly produced by many strains on PDA or SDA, whereas transparent exudates were mainly produced by strains on MMN. We observed the mycelial colonies with a single or multiple textures in just one culture plate. Wrinkled or uneven colony surfaces were remarkably observed in many strains on PDA or SDA, while an even colony surface was observed in many strains on MMN. Sixty percent of Tricholomaceae strains formed wrinkled surface on PDA. However, they did not form any wrinkle on MMN plate. Cottony texture was observed in mycelia colonies of many strains. Velvety texture was often observed in the mycelial colonies on SDA than PDA and accounted for 60% of Suillaceae strains on SDA.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.2
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• pp.73-80
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• 2009

Biofilters use porous solid media to support microorganisms and allow access to the contaminants in the airflow. The characteristics of media used in biofilters vary greatly, and therefore it is important to select the appropriate media in order to obtain a large enough surface attachment area and uniform pore. This study was performed to compare hydrogen sulfide ($H_2S$) removal efficiencies of three biofilter media; coconut fiber, ceramic, and polyurethane. The biofilter packed with coconut fiber showed stable removal activity when inlet loading was changeable, and was restored rapidly when the moisture content decreased. However, the coconut fiber suffered from low durability. To cope with this problem a media of fibrinous polypropylene was developed to strengthen the durability of the coconut fiber. Biofilter column experiments using the fibrinous polypropylene media demonstrated over 99% of removal efficiencies at pH as low as 3 and 6 seconds of EBRT (empty bed gas residence time). Due to its superior physical characteristics, it is expected that the $H_2S$ treatment performance will increase when the new fibrinous polypropylne media is applied in commercial biofilter systems.

• Journal of the Korean Geotechnical Society
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• v.30 no.2
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• pp.77-85
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• 2014

The paper presents comparison between numerical and experimental results to verify finite element algorithm of air diffusion in three-phase porous media. The theory of two-phase flow in partially saturated soil is a fundamental study to predict the safety for $CO_2$ sequestration. Geotechnical engineering problems exposed to atmospheric pressure generally assume that air pressure is equal to zero in three-phase porous media, but the geotechnical engineering problem at a depth of about over 1 km needs to be considered in connection with deformable solid skeleton due to air pressure. Therefore, the objective of this study is to validate the numerical algorithm by comparing with results obtained from measurement of air diffusion and dissipation through drainage test.

• Ecology and Resilient Infrastructure
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• v.3 no.1
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• pp.70-75
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• 2016

The purpose of this study was to develop water-purification vegetation mats consisting of the eco-friendly materials and to validate their water purification capabilities with the objective of reducing nonpoint pollution into streams. The developed vegetation mats are made of coconut fiber shell and filling consisted of zeolite, diatomaceous earth or a mixture of calcinated foam media. The bench scale assessment of the water purification capability of the three filling materials showed that the removal efficiencies of suspended solid (SS), total nitrogen (T-N) and total phosphorus (T-P) were higher in the foam media than in zeolite or diatomaceous earth. From the results of the field experiment, the removal efficiencies of the vegetation mats filled with the foam media were 60.1% in SS, 32.2% in T-N and 20.2% in T-P. Therefore the vegetation mats filled with the foam media calcinated from zeolite and diatomaceous earth should have higher efficiencies in controlling the nonpoint source pollutions in streams.

• Environmental Analysis Health and Toxicology
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• v.14 no.4
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• pp.145-153
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• 1999

Effects of various concentrations of copper in solid fibrous form and methylglyoxal (MG) on phosphorus uptake and growth change of green algae Scenedesmus obliquus were studied. There was significant differences among cultures treated with various concentrations of copper and MG in growth of algae with parameters of cell numbers, photosynthetic rate and cellular morphology, and phosphorus uptake by cell. When the copper in media is treated with 25 mg or 50 mg per 100 ml of Bristol solution, the mean cell number of algae was 15.642${\times}$10$\^$6/ cells$.$ml$\^$-1/ and 12.986${\times}$10$\^$6/ cells$.$ml$\^$-1/, respectively, while those of algae in culture without copper was 18.486${\times}$10$\^$6/ cells$.$ml$\^$-1/. The mean cell area of 2450 ${\mu}$m$^2$, 1894 ${\mu}$m$^2$and 1697 ${\mu}$m$^2$in basic media, basic media with 25 mg of copper and basic media with 50 mg of copper was showed the inhibitory effect of copper on algal growth. The algal growth was stimulated by MG when the culture was treated with 25 mg of copper or without copper, while it was inhibited when the culture was treated with 50 mg of copper. It was considered that there was significant interaction between copper and MG on algal growth. The phosphorus concentration in algal medium treated with 25 mg or 50 mg of copper was 29.435 ppm and 26.224 ppm, respectively, while those of algae in culture without copper was 52.8 ppm, which shows that the application of copper in algal medium can prevent the availability of phosphorus to algal cell.

• Korean Journal of Food Science and Technology
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• v.25 no.3
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• pp.210-213
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• 1993

The purpose of this research was to investigate fluidization characteristics of three solid particles, correlations between voidage and superficial velocity. The inside diameter of a column did not affect the fraction void-superficial velocity relationship for fluidization systems which was obtained as follows: $\frac{u}{u_t}={\varepsilon}^{3.703}----Sea\;Sand$ $\frac{u}{u_t}={\varepsilon}^{3.5665}----long\;Exchange$ $\frac{u}{u_t}={\varepsilon}^{4.066}----GAC$ And the sphericial type media is good for fluidized systems as it maintains low voidage. Actually, if biofilm attached to media (bioparticle), the density became lower in fluidized bed biofilm reactor. Therefore, as the density of media become higher, it is easy to maintain fluidized beds.