• Korean Journal of Environmental Biology
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• v.25 no.4
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• pp.363-369
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• 2007

To understand property of distribution restricted at northern slope of Corylopsis coreana, we investigated process of sedentary formation from seed germination to seedling and its micrometeorological factors in Cheongsogol, Suncheon in Korea. The germination tests were carried out in-situ and manipulated condition, respectively. Air and soil temperatures, relative humidity, soil water contents and PPFD were measured in southern and northern slopes for four seasons. The seeds did not shown difference in germination to azimuth slope. However, seedling in the northern slope should have taken advantage on the sedentary stage of seedlings because there was low temperature and high humidity during the spring. At the southern slope, the seedlings seemed to have a disadvantage on high temperature and low humidity in spring season. Accordingly, the formation of Corylopsis coreana population is influenced by microclimatic factors, especially in low temperature and high humidity at the sedentary stage of the germinated seedlings.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.2
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• pp.249-263
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• 2017

The expansion behavior of inflatable steel pipe rockbolt shows geometric nonlinearity due to its ${\Omega}-shaped$ section. Previous studies on the anchoring behavior of inflatable steel pipe rockbolt were mainly performed using theoretical method. However, those studies oversimplified the actual behavior by assuming isotropic expansion of inflatable steel pipe rockbolt. In this study, the anchoring behavior of the inflatable steel pipe rockbolt were investigated by the numerical method considering the irregularity of pipe expansion and other influencing factors. The expansion of inflatable steel pipe rockbolt, the contact stress distribution and the change of the average contact stress and the contact area during installation were analyzed. The contact stresses were developed differently depending on the constitutive behavior of rocks. Small contact stresses occurred in steel pipes installed in elasto-plastic rock compared to steel pipes installed in elastic rock. Also, the anchoring behaviors of the inflatable steel pipe rockbolt were different according to the stiffness of the rock. The steel pipe was completely unfolded in the case of the stiffness smaller than 0.5 GPa, but it was not fully unfolded in the case of the stiffness larger than 0.5 GPa for the given analysis condition. When the steel pipe is completely unfolded, the contact stress increases as the rock stiffness increases. However, the contact stress decreases as the rock stiffness increases when the steel pipe is not fully expanded.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.12
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• pp.21-26
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• 2018

For evaluating equations of bursting force in different codes, comparative study of the formulas was conducted. Because the equations does not consider variables such as shape of anchorages and duct, a relation between the bursting forces and the variables has to be analyzed. In this paper, the bursting forces equation was proposed by finite element analysis. As evaluation through comparison of the proposed equation with the previous ones and an experiment, it was figured out that bursting force computed by the proposed equation could be used for design of reinforcement in the anchorage zone.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.810-817
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• 2015

This study was conducted to evaluate the pressure treatment characteristics of yellow poplar skin timber with ACQ-2, CUAZ-3, and CuHDO-1. The effect of moisture content (MC) on treatability was investigated, and fixation characteristics of copper-based preservatives were also evaluated. Sapwood of yellow poplar, which was dried below 50 percent MC, was fully penetrated with preservatives, and minimum requirement of preservative retention for the hazard class H3 was achieved. Through measuring retention gradient in yellow poplar sapwood, it was confirmed that minimum requirement of preservative retention for the hazard class H3 was achieved in the assay zone from the surface to 15 mm-depth when the specimens were dried below 30 percent MC. Yellow poplar heartwood did not meet the minimum requirement of penetration and retention for the hazard class H3 over the range of pretreatment MCs tested. The fixation rate of copper was much faster under drying condition compared with nondrying condition; more than 90% of copper were fixed in 3 weeks at $21^{\circ}C$ under drying conditions.

• 보일러설비
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• s.194
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• pp.112-115
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• 2010

보통 이사를 할 때면 이삿짐 싸기, 각종 관리비, 공과금 납부 등 눈 코 뜰새 없이 바쁘다. 하지만 가장 먼저 챙겨야 할 가스안전에 대해서는 정착 잊어버리기 쉽다. 이사가 많아지는 따뜻한 봄철 가족과 가스안전 모두 꼼꼼히 챙길 수 있는 가스안전 상식에 대해 알아보자.

• 한국유가공학회:학술대회논문집
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• 2001.05a
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• pp.37-47
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• 2001

• Nuclear industry
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• v.3 no.4 s.14
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• pp.75-81
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• 1983

현재 일본의 원자력발전규모는 전발전설비의 약 $12\%$를 점유하고 있으며 그 태반이 경수로이다. 따라서 경수로를 정착시키고 안정된 운전을 유지하는 것이 원자력발전에 부과된 앞으로의 과제이다. 이 글은 이들 현황과 문제에 대한 일본 '원자력공업'지 7월호에 수록된 내용을 전재한 것이다.

• Journal of the Korea Concrete Institute
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• v.19 no.3
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• pp.323-331
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• 2007

The development length equations of the GFRP rebars are suggested based on the pullout tests performed in this study. A total of 48 pullout and modified pullout tests were completed. Test variables included embedment length (L=10, 15, 20, and $30d_b$), vertical and horizontal installation of the rebars, height of the rebars (H=100 and 300 mm), and cover thickness $(C=2{\sim}5d_b)$. D13 GFRP rebars domestically developed were used in the experimental program. The average of the bond strength of all vertically installed GFRP rebars was 6.39 MPa with a 5% fractile of 4.63 MPa. A basic development length equation was derived that resulted in an equation equivalent to the one proposed in the ACI 440.1R-03. Careful reevaluation of the bond strength using the modified pullout test indicated that a modification of the design equation was necessary so that the basic development length increases by 11%. The top bar effect of the horizontally installed rebars as well as the effect of the cover thickness were determined and included in the set of suggested equations. Since the current equations were derived from testing rebars embedded in relatively low strength concrete $(f_{ck}=20{\sim}24MPa)$, they result in conservative development lengths when applied to bars embedded in higher strength concretes.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.1
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• pp.61-66
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• 2000

An experiment was conducted to evaluate the effects of seed coating on germination and early growth of tall fescue (Festuca arundinacea Schr.), orchardgrass (Dactylis glomerata L.), and alfalfa (Medicago sativa L.) over sown on unploughed hilly and forested areas. Establishment and early growth of coated tall fescue and orchardgrass on unploughed hilly area were not significantly influenced by seed coating. Establishment and early growth of coated alfalfa on unploughed hilly area were higher than non-coated and showed 4.7% and 4.0 g/m2, respectively. Establishment of coated tall fescue (11.8%) on forested area were higher than noncoated (0.3%), but ealy growth of tall fescue was not significantly influences by seed coating. Establishment of over sown orchardgrass on forested area was not significantly affected by seed coating, but early growth of coated seed (18.7%) was better than that of non-coated (0.3%). Establishment of coated alfalfa on forested area were higher than those of non-coated. Results of this study indicate that the establishment and early growth of over sown tall fescue, orchardgrass, and alfalfa could be improved by seed coating.

• Korean Journal of Veterinary Research
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• v.18 no.1
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• pp.51-60
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• 1978

돼지의 전염성위축성비염(傳染性萎縮性鼻炎)의 주요한 병원균(病原菌)이라고 생각되는 Bordetella bronchiseptica(이하(以下)B균(菌)) 자연감염돈분리유내균주(自然感染豚分離由來菌株)를 사용하여 mouse 비강내정착성(鼻腔內定着性)에 관(對)한 사균면역(死菌免疫)의 효과(效果)를 검토하고자, 먼저 상변리(相變異)에 따르는 균(菌)의 독역(毒力)과 감염방어성(感染防禦性)을 비교함과 동시에, I 상균불활화예방액(相菌不活化豫防液)의 면역원성(免疫原性)에 관(對)한 기초적인 검토를 실시하였고, 이에 계속하여 생균비강내접종(生菌鼻腔內接種)에 따르는 균(菌)의 정착성(定着性)과 혈중응집(血中凝集) 항체(抗體)의 경시적(經時的)인 추이(推移)를 검토하였다. 얻어진 성적을 요약하면 다음과 같다. 1. B균(菌) I 상균(相菌)(W-1029주(株))의 독역(毒力)은 III 상균(相菌)(H-969주(株))에 비하여 독역(毒力)이 강하였으며, I 상균(相菌)은 감염방어성(感染防禦性)을 보유하고 있었으나 III 상균(相菌)은 감염방어성(感染防禦性)이 전혀 없었다. 2. B균(菌) I 상균사균면역(相菌死菌免疫)에 있어서 formalin과 merthiolate 처리(處理) 및 불활화온도(不活化溫度)($0^{\circ}C$및 $37^{\circ}C$)간(間)에는 현저한 면역원성(免疫原性)의 차이는 인정할 수 없었다. 3. 사균면역(死菌免疫)을 실시한 mouse 군(群)에 생균(生菌)의 경비접종(經鼻接種)에 의하여 경시적(經時的)으로 균(菌)의 호흡기도내(呼吸氣道內)의 정착성(定着性)과 혈중응집항체가(血中凝集抗體價)의 추이(推移)를 보았던 바, 비면역대조군(非免疫對照群)에 비하여 면역군(免疫群)은 현저한 면역효과(免疫效果)를 나타내었으나, 면역군(免疫群)에서 간헐적(間歇的)인 배균(排菌)이 상당기간에 걸쳐 인정되었으며 또한 응집항체가(凝集抗體價)의 상승에 따르는 비강내정착균(鼻腔內定着菌)의 완전소실(完全消失)은 다소 곤난함이 인정되었다. 이상(以上)의 성적(成積)으로 B균사균항원(菌死菌抗原)을 사용하여 고도(高度)의 면역(免疫)을 시킴으로서 비강내(鼻腔內)에 있어서의 B균(菌)의 정착(定着)을 조지(阻止)할 수 있는 가능성(可能性)이 시사(示唆)되나 항체가(抗體價)의 상승(上昇)에 따르는 균(菌)이 비강내(鼻腔內)에서 완전 소실(消失)이 다소 곤난한 점은 본균(本菌)과 호흡기도점막감염(呼吸器道粘膜感染)의 실태(實態)를 시사(示唆)하는 것으로 보아진다.