• Environmental Engineering Research
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• v.17 no.4
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• pp.191-196
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• 2012

Analysis of hydrological safety as well as the determination of many substance concentrations are necessary when bioreactor systems are introduced to landfill operations. Therefore, hydrological and substance balance model was developed since it can be applied to various bioreactor landfill operation systems. For the final evaluation of the model's effectiveness, four different methods of injections (leachate alone, leachate and organic waste water, leachate and reverse osmosis concentrate, and all the above three combination) was applied to 1st landfill site of Sudokwon landfill. As a result, the water content of the hypothetical cases for four different systematic bioreactors is projected to be increased up to 35.5% in next 10 years, and this indicated that there will be no problems in meeting the hydrological safety. Also, the final $Cl^-$ concentration after 10-yr time period was projected to be between from minimum 126 to maximum 3,238 mg/L, which could be still a decrease from the original value of 3,278 mg/L. According to the proposed model, whether the substance concentration becomes increased or decreased largely depends on the ratio of initial quantity of inner landfill leachate and the rate of injection.

• Microbiology and Biotechnology Letters
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• v.38 no.2
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• pp.198-206
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• 2010

The aim of this work was to investigate the synergically bactericidal effects and cellular responses of tea polyphenols (TPP) and imipenem on imipenem-resistant Pseudomonas aeruginosa. Imipenem-resistant Ps. aeruginosa was isolated from patient in hospital. The bactericidal effects of TPP and imipenem were evaluated on the basis of its minimum inhibitory concentrations (MIC). The combined use of TPP and imipenem resulted in 16-fold and 8-fold reductions in the MICs of imipenem for the imipenem-susceptible and imipenem-resistant Ps. aeruginosa, respectively. The bactericidal effects of the imipenem and TPP against the Ps. aeruginosa was evaluated using the time-kill assay. The synergetic effects of the combinations of TPP and imipenem against Ps. aeruginosa were confirmed. Western blot using anti-DnaK and anti-GroEL monoclonal antibodies was performed to investigate the expression of stress shock proteins (SSPs) in imipenem-susceptible and imipenem-resistant strains exposed to TPP. The amount of SSPs were induced as the exposure time increased and decreased. The molecular weights of DnaK and GroEL were 70 kDa and 60 kDa, respectively. SDS-PAGE with silver staining revealed that the amount of lipopolysaccharides (LPS) increased or decreased in the strain treated to different concentrations and exposing periods of TPP. Scanning electron microscopic analysis demonstrated the presence of umblicated and wrinkled surfaces for cells treated with TPP or imipenem.

• Journal of Korean Society of Transportation
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• v.30 no.5
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• pp.11-21
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• 2012

As a strategy to enhance traffic management, roundabouts come to the fore recently to decrease traffic accidents, streamline traffic flows, and expedite the realization of green transportation. As local governments introduced roundabouts, new road sign standards have to be established because the existing road sign regulations cannot be applied to roundabouts. Prior to trying to make suitable specification of sub-destination signs in roundabouts, regulations of other countries were examined and modified. The legend and location was calculated so that drivers could turn in time. Two specifications were determined by simulation experiments. As a result, drivers could read signs at right side better than at traffic island, and turn in time at 15cm legend size. Consequently, we proposed the minimum specifications and optimal locations of sub-destination signs.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.37-37
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• 2018

We use two different methods for laboratory propagation from seed of lady's slipper orchid(Cypripedium macranthos Sw.); immature seed which also called green capsule or fully mature seed about 120~130 days from pollination. In green capsule culture, the seed pods should be collected within precisely right time. The right time of seed collection could be diverse under the wether conditions or nutritional factors of the plants. In fully matured seed culture, the more complicated procedures are needed to break the dormancy of the seed; thermal or chemical treatment. The seedlings in this study were easily germinated from immature seeds in Harvais medium; 53 days after pollination(DAP) in Cypripedium pubescens, DAP 65 in C. parviflorum and C. macranthos. The germinated seedlings were transplanted to hormone free media immediately to avoid abnormal growth of seedlings. When the seedlings have roots with a minimum length of around 2-3cm and have visible dormant buds, the seedlings were removed from the flask and stored in refrigerator for vernalization. To examine the correlation of seedlings and maternal plants, the 125 seedlings of C. macranthos were transplanted in the soil bed at a distance of 20-100 cm from mother plants on April 20. The survival rate of seedlings were 92% in 20 cm distance from the ripe plants, and 56 % in 100 cm distance. The seedlings which were transplanted near mother plants showed vigorous growth in plant height, leaf width, and especially dormant buds. Considering the existence of mycorrhiza which is a symbiotic association between a fungus and the roots of a orchid vascular, the various fungus from mother plants could affect the growth of the seedlings. These results indicate the possibility of high and stable production and practical industrialization of endangered lady's slipper orchids.

• Restorative Dentistry and Endodontics
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• v.38 no.4
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• pp.241-247
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• 2013

Objectives: The aim of this study was to determine the effect of epigallocatechin gallate (EGCG) on the shear bond strength of composite resin to bleached enamel. Materials and Methods: Ninety enamel surfaces of maxillary incisors were randomly divided into 9 groups as follows: G1: control (no bleaching); G2: bleaching; G3: bleaching and storage for seven days; G4 - 6: bleaching and application of 600, 800 and 1,000 ${\mu}mol$ of EGCG-containing solution for 10 minutes, respectively; G7 - 9: bleaching and application of 600, 800 and 1,000 ${\mu}mol$ of EGCG-containing solution for 20 minutes, respectively. The specimens were bleached with 30% hydrogen peroxide gel and a composite resin cylinder was bonded on each specimen using a bonding agent. Shear bond strength of the samples were measured in MPa. Data was analyzed using the two-way ANOVA and Tukey HSD tests (${\alpha}$ = 0.05). Results: The maximum and minimum mean shear bond strength values were observed in G1 and G2, respectively. Time and concentration of EGCG showed no significant effects on bond strength of the groups (p > 0.05). Multiple comparison of groups did not reveal any significant differences between the groups except for G2 and all the other groups (p < 0.05). Conclusions: There is a significant decrease in bond strength of composite resin to enamel immediately after bleaching. A delay of one week before bonding and the use of EGCG increased bond strength of composite resin to bleached enamel.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.3
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• pp.163-168
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• 2001

"Hwasan 103" is a new cold-tolerant Italian ryegrass(Lo1ium multiflorum L.) variety developed by theNational Livestock Research Institute(NLR1) in 1999. To develop a cold-tolerant variety of Italianryegrass(Lo1ium multiflorum L.), cold-tolerant clones survived under - 13 - - 14$^{\circ}$C of minimum average airtemperature(MAAT) in January were selected at Hwachun, Kwangwon Province in 1995. Five clones ofselected clones were polycrossed for seed production by NLRI, RDA in 1996."Hwasan 103" was diploid variety, green in leaf color and broad in flag leaf width. Also it hassemi-prostrate and medium growth habit in late autumn and in early spring, respectively. "Hwasan 103" wasexcellent in lodging tolerance at harvesting time. First heading date of "Hwasan 103" was 14th May, it wassimilar to that of Marshall. Expecially, "Hwasan 103" survived about 50-70% under - 10- - 12'C ofMAAT in January, so it could be cold-tolerant variety that can be safely cultivated in regions higher than -9$^{\circ}$C of MAAT in January. Compared with Marshall "Hwasan 103" showed 3% higher fresh yield (57.8MTper ha) and it showed 2% higher dry matter yield (11.OMT per ha). Higher IVDMD and TDN and lowerADF and NDF were observed in "Hwasan 103" than those of Florida 80 and Marshall in Forage quality.(Key words : Italian ryegrass, Cold tolerance, New variety "Hwasan 103")all in Forage quality.(Key words : Italian ryegrass, Cold tolerance, New variety "Hwasan 103")n 103&")ot;)

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.3
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• pp.157-162
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• 2001

"Hwasan 102" is a new cold-tolerant Italian ryegrass(Lo1ium rnultiflorum L.) variety developed by theNational Livestock Research Institute(NLRI) in 1999. Having cold tolerance in Italian ryegrass is an importantfor enlargement of cultivation area and increase of productivity in Korea. To develop the cold-tolerant varietyof Italian ryegrass, cold-tolerant clones survived under - 13- - 14$^{\circ}$C of minimum average air temperature(MAAT) in January were selected at Dun Nae, Kwangwon Province in 1993. Five of selected clones werepolycrossed for seed production by NLRI, RDA, in 1995."Hwasan 102" was tetraploid variety, dark green in leaf color and broad in flag leaf width. Also it hassemi-prostrate and medium growth habit in late autumn and in early spring, respectively. "Hwasan 102" withlow plant height at harvesting time was excellent in lodging tolerance. First heading date of "Hwasan 102"was 19th May, it was similar to that of Marshall. Expecially, "Hwasan 102" survived about 60% under - 10- - 12$^{\circ}$C of MAAT in January, so it could be cold-tolerant variety that can be safely cultivated in regionshigher than -9'C of MAAT in January. Compared with Marshall, "Hwasan 102" showed 8% higher freshyield (59.2MT per ha) but it showed 2% lower dry matter yield (9.6MT per ha). Higher IVDMD and TDNand lower ADF and NDF were observed in "Hwasan 102" than those of Florida 80 and Marshall in Foragequality.(Key words : Italian ryegrass, Cold tolerance, New variety "Hwasan 102")rshall in Foragequality.(Key words : Italian ryegrass, Cold tolerance, New variety "Hwasan 102")san 102&")ot;)

• KEPCO Journal on Electric Power and Energy
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• v.2 no.4
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• pp.577-582
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• 2016

This Study focused on the development of SMPS (Switching Mode Power Supply) to supply the constant votage and current nevertheless LED fluorescent Light generated the electric noise (with Harmonics) and Inrush current at instant time of turn-on and off. Recently, according to the Green policy in government, the LED fluorescent Lighter showed the rapidly increasing tend as indoor and outdoor Lighter. But, because of costs, LED fluorescent Light not considered and neglected the following items; power factor, efficiency, Harmonics and Inrush current. So, we are developed the SMPS about 3 key issues as follows: 1st, power factor and efficiency is 85%. 2nd, the switching noisy by harmonic is minimized. 3rd, the Inrush current at turn on and off time is reduced the minimum 0.3 A after $100{\mu}sec$ on turnon time. The proposed SMPS adjusted by LNK 409 driver (included the high frequency modulation function). Although, the developed SMPS maintained the about 85% of power factor and efficiency. but, the SMPS must be generated low heat by the variation of minute load current at switching timing. To improve the above weak point, the developed SMPS have the feedback monitoring circuit between input side and output side to maintain the power factor and efficiency. Also, we are studied the time-constant of control circuit to output the constant voltage and current nevertheless the load disturbance of LED lighting. The LED fluorescent Light of 46W is checked the above items.

• Korean Journal of Remote Sensing
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• v.35 no.5_2
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• pp.819-829
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• 2019

In the disaster of collapse, an immediate response is needed to prevent the damage from worsening, and damage area calculation, response and recovery plan should be established. This requires accurate detection of the damage affected area. This study performed the detection of the damaged area by using UAV which can respond quickly and in real-time to detect the collapse accident. The study area was selected as B-05 housing redevelopment area in Jung-gu, Ulsan, where the demolition of houses and apartments in progress as the redevelopment project began. This area resembles a collapsed state of the building, which clear changes before and after the demolition. UAV images were acquired on May 17 and July 9, 2019, respectively. The changing area was considered as the damaged area before and after the collapse of the building, and the changing area was detected using CVA (Change Vector Analysis) the Representative Change Detection Technique, and SLIC (Simple Linear Iterative Clustering) based superpixel algorithm. In order to accurately perform the detection of the damaged area, the uninterested area (vegetation) was firstly removed using ExG (Excess Green), Among the objects that were detected by change, objects that had been falsely detected by area were finally removed by calculating the minimum area. As a result, the accuracy of the detection of damaged areas was 95.39%. In the future, it is expected to be used for various data such as response and recovery measures for collapse accidents and damage calculation.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.1
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• pp.54-59
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• 2009

It was difficult for the existing rotary kiln to fabricate the fine aggregates under 3 mm due to the sticking phenomenon between specimens. In this study, the vertical type fluidizing furnace was designed and manufactured by which the lightweight fine aggregates of specific gravity $1.1{\sim}1.7$, water absorption $11{\sim}19%$ could be fabricated from the green body of clay: stone sludge: spent bleaching clay = 60 : 30 : 10 (wt%) without sticking-together happening. The minimum sintering temperature for bloating of aggregates was $1130^{\circ}C$. The specimens sintered over $1140^{\circ}C$ showed the typical bloating characteristics of lightweight aggregates and an inner layer was discovered due to widened cracks on a surface. But the crack on a surface did not propagate into a black core area so had no effect on a water absorption of aggregates. The sintering temperature made the thickness of shell and the black core area thin and expanded respectively but the sintering time did not affect the microsturcture of aggregates. The water absorption of aggregates decreased with increasing temperature owing to increased amount of liquid formed on a surface. Also sintering time affected a lot on a water absorption because it takes a time to form a liquid, which change the open pores to closed pores by blocking.