• Journal of Korean Society of Steel Construction
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• v.25 no.6
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• pp.601-612
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• 2013

In the present study, details of the TSC beam-to-PSRC column connection for low and middle seismic zones were developed. For ease construction, the top and bottom flanges of the steel section of the TSC beam were discontinuous at the joint face on purpose, while the web passes through the joint. Thus, tensile resistance of the top and bottom flanges is not considered in the calculation of nominal strength of the connection. Cyclic loading tests on two interior connections and an exterior connection were performed to verify the seismic performance. The test parameter for two interior connections was the depth of the TSC beams: 600 and 700 mm including the slab depth. The test results showed that the nominal strength of the connections predicted by KBC 2009 correlated well with the test results. The connection specimens exhibited relatively good deformation and energy dissipation capacities, greater than the requirements for the ordinary and intermediate moment frames. Ultimately, the connection specimens were failed at the story drift ratios of 3.0 to 4.0 % due to local buckling and tensile fracture of the web of the TSC beam passing through the joint. By modifying the existing provisions of ASCE, the joint shear strength of the TSC beam-PSRC column connection was evaluated.

• Korean Journal of Environmental Biology
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• v.24 no.4
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• pp.359-367
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• 2006

The vascular plants of this site were identified as 641 taxa through field investigation; 101 families, 340 genera, 547 species, 80 varieties, 12 forms, 1 subspecies and 1 hybrid. Based on the Rare plants of the Forest Service and Korea Forest Research Institute, 9 taxa were listed except implanted species; Loranthus tanakae, Aristolochia manshuriensis, Aristolochia contorta, Viola albida, Cypripedium macranthum, Schpolia japonioa, Acanthopanax chiisanensis, Rhododendron micranthum. Based on the Korean endemic plants, 18 taxa were listed; Salix purpurea var, japonica, Asarum sieboldii var. mandshuricum for. misnadrum, Persicaria lapathifolia for. alba, Pseudostellaria sylvatica, Aconitum pseudolaeve var. erectum, Corydalis maculata, Corydazis albipetala, Corydalis grandicazyx, Cardamine amaraeiormis, Chrysosplenium barbatum, Filipendula glaberrima, Lespedeza x tomentella, Acanthopanax chiisanensis, Melampyrum setaceum var. nakaianum, Weigela subsessilis, Adenophora triphylla var. hirsute, Cirsium setidens, Saussurea pseudogracilis. Specific plant species by floral region were total 81 taxa (12.6%); Prunus yedoensis in class V, 13 taxa (Thuja orientalis, Cimicifuga heracleiiolia, Sedum middendorffianutn, Rhododendron micranthum, etc.) in class IV, 17 taxa (Equisetum palustre, Aceriphyllum rossii, Angelica gigas, Cirsium setidens, etc.) in class III, 15 taxa (Heloniopsis orientalis, Lychnis cognata, Saxifraga oblongifolia, Viola orientalis, etc.) in class II, 35 taxa (Hosta capitata, Cimicifuga simplex, Chrysosplenium flagelliferum, Campanula punctata, etc.) in class I. So, the naturalized plants were listed 53 taxa and the naturalization index was 8.2%, urbanization index was 20.7%.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.69-69
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• 2018

벼룩이울타리(Arenaria juncea M.Bieb.)는 청열, 양혈, 허로기열, 골증, 수심작열, 도한 등의 약효가 있으며, 백색의 꽃이 취산화서로 아름답게 개화하여 조경소재로 이용가치가 높다. 본 연구는 벼룩이울타리의 육묘기술 개발을 위하여 2017년 6월 2일부터 7월 31일까지 8주간 수행하였다. 실험의 대조구는 200구 트레이에 원예상토를 충진하고 종자를 셀 당 3립씩 파종하여 무차광 조건에서 육묘하였으며, hyponex $500mg{\cdot}L^{-1}$를 2회 추비하였다. 토양 실험은 원예상토[$300-200-200mg{\cdot}L^{-1}$(N-P-K)]와 피트모스:펄라이트(3:1), 코코피트:펄라이트(3:1) 혼용토를 이용하였으며, 원예상토를 제외한 모든 토양은 0-0-0, 300-200-200, $600-400-400mg{\cdot}L^{-1}$의 비료를 첨가하였다. 종자는 셀당 1, 3, 5립을 파종하였고, 추비는 hyponex (6.5-6-19)를 0, 500, $1000mg{\cdot}L^{-1}$로 4, 6주차에 총 2회 잎이 충분히 젖을 정도로 살포하였다. 차광은 0, 55, 75%로 설정되었다. 벼룩이울타리 육묘의 결과, 토양 종류별로는 원예상토에서 초장이 가장 길었으며, 다음으로 피트모스 혼용토의 순이었다. 피트모스 혼용토에서 육묘한 유묘의 초장은 비료를 첨가하지 않은 처리구에서 길어지는 경향을 보였다. 경직경과 근장은 원예상토 단용구와 코코피트 혼용토가 피트모스 혼용토에 비해 양호하였다. 엽수는 상토(26.1 ea)에서 가장 많았고 다음으로 비료 코코피트 혼용토 $600-400-400mg{\cdot}L^{-1}$(22.9 ea)의 순이었다. 셀 당 파종립수를 달리하여 육묘한 결과, 초장은 파종립수가 적을수록 길었으며, 경직경과 엽수는 처리에 따른 유의적인 차이를 확인할 수 없었다. 추비 처리별로 전반적인 생육은 큰 차이는 보이지 않았으나, 경직경은 처리농도가 낮을수록 두꺼워지는 경향이었다. 엽수는 hyponex 처리시 무처리구에 비해 증가하는 경향을 보였으며, $500mg{\cdot}L^{-1}$ 처리구에서 가장 많았다. 차광정도에 처리에 따른 생육은 차광률이 높을수록 생육이 억제되는 경향이었다. 초장, 엽수 및 근장은 무차광에서 차광처리구에 비해 우수하였다. 경직경은 무차광구와 50% 차광구가 70% 차광구에 비해 증가하였다. 지상부, 지하부의 생 건체중도 무차광에서 가장 무거웠으며, 차광률이 증가할수록 감소하였다.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.56-56
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• 2018

가는잎향유는 우리나라에 자생하는 고유종으로 꽃이 아름답고 향이 좋아 관상 및 약용으로 사용되나, 무분별하게 남획되기도 하여 자원의 보호가 요구되는 실정이다. 이에 본 연구는 가는 잎향유의 종 유지 및 재배방법 확립을 위하여 종자를 이용한 육묘조건을 조사하였다. 연구 내용은 파종용기, 파종립수, 토양종류, 추비농도 및 차광정도 등을 각 처리별로 2017년 6월 2일부터 7월 31일까지 약 8주간 수행되었다. 가는잎향유의 종자를 162, 200, 288구 트레이 및 사각분에 파종한 처리 중, 162구 트레이 처리구에서 엽면적과 지하부 생체중이 가장 넓거나 무거웠으며, 파종립수는 한 cell당 2립 처리구에서 초장이 안정적이고 엽면적이 넓었다. 파종용 상토로는 피트모스:펄라이트(3:1) 처리구가 코코피트:펄라이트(3:1) 처리구보다 생육에 효과적이었으며, 비료는 혼용토에 $300-200-200mg{\cdot}L^{-1}$(N-P-K)를 혼합한 처리구에서 발아율, 마디수, 엽록소 지수 등이 우수하였다. 재배관리는 추비는 hyponex를 농도별로 시비하였으나, 무처리구보다 생육에 효과적이지는 않았다. 또한, 재배시 차광처리를 하지 않는 것이 가는잎향유의 실생육묘에 유리하였다. 따라서, 가는잎향유의 육묘를 위해서는 피트모스:펄라이트(3:1) 혼용토에 비료를 $300-200-200mg{\cdot}L^{-1}$를 첨가한 토양을 162구 트레이에 충진하여, 한 cell에 2립씩 파종하고 무차광 조건에서 재배하며, 추비는 처리하지 않는 것이 생육에 가장 효과적일 것으로 생각된다.

• Korean Journal of Materials Research
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• v.10 no.1
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• pp.55-61
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• 2000

The sintering characteristics of PVA-Al(III) complex added $UO_2$ pellet and AlOOH added $UO_2$pellet were compared. The major phase of PVA-Al(III) complex and AlOOH decomposed at $1000^{\circ}C$ in $H_2$atmosphere was $\theta-Al_2O_3$. Compared with the apparent density of pure $UO_2$, that of AlOOH added $UO_2$ powder was higher but that of PVA-Al(III) complex was lower. the densification of AlOOH added $UO_2$ pellet was initiated at about $800^{\circ}C$, the densification of PVA-Al(III) complex added $UO_2$ pellet was initiated at about $900^{\circ}C$ respectively. In a view of pore size distribution, the PVA-Al(III) complex added $UO_2$ pellet appeared as monomodal type, whereas the AlOOH added $UO_2$ pellet appeared as bimodal type. The grain size of AlOOH added $UO_2$ pellet was about $13\mu\textrm{m}$ but the grain size of PVA-Al(III) complex added $UO_2$ pellet was increased up to about $36\mu\textrm{m}$.

• Journal of the Korean Ceramic Society
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• v.41 no.4
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• pp.284-288
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• 2004

To improve mechanical properties of $Al_2$O$_3$/ZrO$_2$composites have been controlled dispersion of ultra low size ZrO$_2$ particles in $Al_2$O$_3$ ceramics by polymeric precursor method (Pechini process). In case of coprecipitation or mechanical mixing of ZrO$_2$ powders with $Al_2$O$_3$, homogeneous dispersion and controlling the ZrO$_2$ size were relatively difficult due to high sintering temperature. So the polyesterization process of Zr/Y(NO$_3$)$_3$-citric acid solution in ethylene glycol with the commercial sub-micron sized o(-alumina powder (Sumitomo AES-11(0.4 ${\mu}{\textrm}{m}$)) was adopted in order to obtain homogeneous dispersion of ZrO$_2$ in A1203. By this partial polyesterization process, the homogeneous dispersion of relatively low sized ZrO$_2$in $Al_2$O$_3$/ZrO$_2$composites was achieved at 1450∼1$600^{\circ}C$ of sintering temperature range and their mechanical properties were measured.

• Asian Journal of Turfgrass Science
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• v.19 no.2
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• pp.85-94
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• 2005

A fungal isolate was newly collected from Zoysiagrass 'Anyang-Joongji' in small circular patches on a fairway ofa golf course in Korea, which seriously occurred during the early summer period of 2005. The isolate presented on PDAmedium, named Scz1, was closely identical to Sclerotinia homoeocarpa, a casual fungus of dollar spot disease, in cool season turf grasses such as creeping bentgrass. Hereby, this study was accomplished to characterize the isolate and compare it with the fungus, named Scb1, isolated from dollar spot-infected creeping bentgrass (Agrostis palustris Huds. cv Penncross). On PDAmedium, individual mycelial appearance of three isolates was very similar except for the pigment. Mycelial pigments of Scz1 and Scz2 (another analogous isolate collected) were light pinkish on the reverse side of PDA medium but that of Scb1 was dark brownish. In a microscopic study, three isolates were barely distinguishable in the appearance of mycelia. As expected, in the temperaturesensitivity assay, all pathogens were very delicate to $32^{circ}C$ above but not to $30^{circ}C$ below, in which was explained to be one of typical characteristics in S. homoeocarpa. In an artificial inoculation assay, disease symptoms including leaf spots in Zoysiagrass were appeared within 6-7 days after inoculation through the hand inoculation method with the isolate-infested soil. Then the fungus was re-identified from the infected leaf tissues. Interestingly, inoculation of isolate Scz1 gave rise to distinct symptoms in only Zoysiagrass but not in creeping bentgrass 'Penncross' and Kentucky bluegrass 'Midnight'. The observation might be involved in host specific pathogenecity of S. homoeocarpa Scz1 to Zoysiagrass. In a chemical sensitivity assay for the isolate, Scz1, showed a high mycelial inhibition against two fungicides, iprodione and propiconazole. All results described above suggest that S. homoeocarpa Scz1 is a primary pathogen of Zoysia dollar spot disease.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.3
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• pp.7-12
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• 2018

The effects of Ru deposition temperature and post-annealing conditions on the interfacial adhesion energies of atomic layer deposited (ALD) Ru diffusion barrier layer and Cu thin films for the advanced Cu interconnects applications were systematically investigated. The initial interfacial adhesion energies were 8.55, 9.37, $8.96J/m^2$ for the sample deposited at 225, 270, and $310^{\circ}C$, respectively, which are closely related to the similar microstructures and resistivities of Ru films for ALD Ru deposition temperature variations. And the interfacial adhesion energies showed the relatively stable high values over $7.59J/m^2$ until 250h during post-annealing at $200^{\circ}C$, while dramatically decreased to $1.40J/m^2$ after 500 h. The X-ray photoelectron spectroscopy Cu 2p peak separation analysis showed that there exists good correlation between the interfacial adhesion energy and the interfacial CuO formation. Therefore, ALD Ru seems to be a promising diffusion barrier candidate with reliable interfacial reliability for advanced Cu interconnects.

• Journal of the Korean Magnetics Society
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• v.6 no.4
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• pp.242-250
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• 1996

The effects of annealing in magnetic field after deposition on electromagnetic properties of $Ni_{81}Fe_{19}$ thin($400\;{\AA}$) films prepared by RF-magnetron sputtering were investigated in terms of microstructure and surface morphology. The coercivity of the films was decreased below $300^{\circ}C$ due to stress relief and recrystallization, while increased at $400^{\circ}C$ due to grain growth and increasing the surface roughness. And then, $4{\pi}M_{s}$, was almost independent of annealing temperatures. Increasing the annealing temperature. the electrical resistivity of films was decreased from $37\;{\mu}{\Omega}cm$ to $24\;{\mu}{\Omega}cm$, the magnetoresistance was nearly a constant of about $0.6\;{\mu}{\Omega}cm$, and the MR ratio was increased from 1.5 % to 3.1 %. Therefore, It was shown that increasing the magnetoresistive ratio was mainly affected by decreasing the electrical resistivity. Considering the practical application of the films for magnetoresistive heads, optimal annealing conditions was obtained after one hour annealing at $300^{\circ}C$ in 400 Oe unidirectional magnetic field.

• Korean Journal of Plant Resources
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• v.27 no.5
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• pp.534-539
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• 2014

This study was carried out to establish seed propagation method of Hydrangea petiolaris Siebold & Zucc., one of the specific and protected plant species for the floral region. Seed size ranged $1.36{\times}0.84mm$, weight of thousand seeds was $2.3{\pm}0.02mg$. Observation of seed morphology characters showed wrinkled surface and elliptical shape, indicating amber color and fine seeds. Moisture contents of seeds, increased rapidly by water-soaking treatment, recording maximum moisture contents (31.9%) after 48 hours. Percent germination of seeds was higher under the light than dark condition. Seed germination was the best at $25^{\circ}C$ under the light condition (78.0%) among temperature and light conditions treated. Percent germination, germination energy and $T_{50}$ was greatly improved by soaking in $GA_3$ solutions for 48 hours. Especially, $100{\sim}500mg{\cdot}L^{-1}$ $GA_3$ treatment resulted in the highest germination rate as 90.0% and above.