• Title/Summary/Keyword: Research Forest

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Visitor Behavior and Importance-Satisfaction Analysis in Provincial Wando-arboretum (도립 완도수목원 방문객의 이용행태 및 중요도-만족도 분석)

  • Kim, Min-Hee;Jin, Seung-Hyun;Park, Jong-Suk;Ahn, Young-Sang;An, Ki-Wan
    • Journal of Forest and Environmental Science
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    • v.28 no.1
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    • pp.37-45
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    • 2012
  • A study surveyed to visitor's user behavior and importance-satisfaction in the Provicial Wando-arboretum. As the results of the research, Most of the visitors are 40s and 50s and live in Jeonnam Region, Gwang-ju. The purpose of their visit was recreation, leisure or experience of a warm-temperate forest. Also the mean of importance was 3.94 and the mean of satisfaction was 3.51 in the Wando-arboretum. It appeared necessary for items of program development, homepage management and amenities including public toilet. The research results are expected to suggest efficient management measures. And expects with the research result that will be the possibility of raising the qualitative satisfaction of the visitor.

Effect of Environmental Pre-treatment on Expression of Blister Rust Resistance in Pinus monticola (oral)

  • Woo, K.S.;Kim, Y.J.;Mcdonald, G.I.;Fins, L.
    • Proceedings of the Korean Society of Plant Pathology Conference
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    • 2003.10a
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    • pp.112.2-112
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    • 2003
  • Levels of blister rust infection (from Cronartium ribicola) varied in western white pine(Pinus monticola Dougl.) seedlings grown in two nurseries in northern Idaho. This observation suggested the potential importance of environmental components operating on the blister rust pathosystem. In an experiment designed to test the influence of environmental conditions at two nurseries, seedlings of a single genetic source were unintentionally held in cold storage for 6 months longer at one nursery than at the other. Subsequently, these seedlings, which had been growing under nursery conditions for 7 months or 1 month, were inoculated with blister rust spores on September 9th, 1999. Infection efficiency measured on the seedlings with only 1 month of growth was 70X greater than on the seedlings that had 7 months for their new growth to mature. Results from this nursery test and infection levels of northern Idaho resistant selections in mild climates suggest that expression of genes related to rust resistance in western white pine can be manipulated by regulation of phonology. If so, several new molecular tools may be employed to enhance our understanding of environmental regulation of genes for blister rust resistance.

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Structural Performance Evaluation on Stress-Laminated Timber Bridge Deck Using Finite Element Analysis (유한요소해석을 이용한 응력적층 바닥판의 구조성능평가)

  • Shin, Yukyung;Eom, Chang-Deuk;Lee, Sang-Joon
    • Journal of the Korean Wood Science and Technology
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    • v.42 no.1
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    • pp.20-26
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    • 2014
  • This paper represented the finite element analysis to estimate structural performance of stress-laminated deck, which is determined by deflection, stress, and aging characteristics of tensioning. After loading, the deflected shape showed plate behavior because pre-stressing make frictional force between each member. Compared between initial post-tension and the results, pre-stressing forces were decreased with deck deflection. This is because deflection occurred in the deck so that pre-stressing decreased due to load reduction. However, material plasticity was not considered so that advanced researches should be performed.

Experimental Study on Reinforcement Effects of Soil Shear Strength by Nylon Net(Substitute Materials Simulating a Root System) -Analysis using Simple Shear Tester under Soil Suction Control - (Nylon Net(대체근계)의 토질강도보강효과에 대한 실험적 연구 - 토양수분제어하의 단순전단시험에 의한 해석 -)

  • Lee, Chang-Woo;Youn, Ho-Joong;Jeong, Yongho
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.9 no.3
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    • pp.76-81
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    • 2006
  • The reinforcement of soil shear strength by nylon net as substitute materials simulating a fine root system was evaluated by soil strength parameters(apparent cohesion(c) and internal friction angle(tan${\phi}$), using simple shear tester which clearly depicts shear deformation and controls soil suction. And the results of shear test by using bamboo as a substitute materials simulating a main root system and using nylon net as a substitute materials simulating a fine root system were compared. The reinforcement of soil strength by nylon net are expressed by apparent cohesion more than internal friction angle. In addition the increment of apparent cohesion by nylon net reached a peak in suction 60 $cmH_2O$. Different from with bamboo, the possibility of the change on internal friction angle(tan${\phi}$) caused by the soil water condition was shown in shear strain 20% condition. These results show that the mechanism of reinforcement by substitute materials simulating root system may be different in the condition of various soil water content.

Thermal Behavior of Hwangto and Wood Flour Reinforced High Density Polyethylene (HDPE) Composites

  • Lee, Sun-Young;Doh, Geum-Hyun;Kang, In-Aeh
    • Journal of the Korean Wood Science and Technology
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    • v.34 no.5
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    • pp.59-66
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    • 2006
  • The thermal properties of wood flour, Hwangto, and maleated polyethylene (MAPE) reinforced HDPE composites were investigated in this study. The thermal behavior of reinforced wood polymer composites was characterized by means of thermogravimetric (TGA) and differential scanning calorimetric (DSC) analyses. Hwangto and MAPE were used as an inorganic filler and a coupling agent, respectively. According to TGA analysis, the increase of wood flour level increased the thermal degradation of composites in the early stage, but decreased in the late stage. On the other hand, Hwangto reinforced composites showed the higher thermal stability than virgin HDPE, from the determination of differential peak temperature ($DT_p$). Decomposition temperature of wood flour and/or Hwangto reinforced composites increased with increase of heating rate. From DSC analysis, melting temperature of reinforced composites little bit increased with the addition of wood flour or Hwangto. As the loading of wood flour or Hwangto to HDPE increased, overall enthalpy decreased. It showed that wood flour and Hwangto absorbed more heat energy for melting the reinforced composites. Hwangto reinforced composites required more heat energy than wood flour reinforced composites and virgin HDPE. Coupling agent gave no significant effect on the thermal properties of composites. Thermal analyses indicate that composites with Hwangto are more thermally stable than those without Hwangto.

Structural Performance of Finger-Jointed Lumber with Different Joint Configurations

  • Lee, Sang-Joon;Eom, Chang-Deuk;Kim, Kwang-Mo
    • Journal of the Korean Wood Science and Technology
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    • v.39 no.2
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    • pp.172-178
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    • 2011
  • Three different finger-jointed lumbers which have different geometric features and adhesives were manufactured and studied in this study. Larch and pitch pine lumbers with and without preservative treatment were used. Bending MOE was measured as the preliminary investigation for grouping the specimen. After the finger, bending MOE of two wood species without preservative treatment shows over 97% property of the control group. The tensile modulus also shows almost same property after the finger joint. And it is found out that the preservative treatment induce little effect on bending and tensile MOE. Based on this result, high performance of examined finger-jointed lumber can be found out. However, tensile strength decreased around 20% which would be induced by the crack along the root of the finger which is formed near the edge during manufacturing stage. And finger-jointed lumber with preservative treatment even shows higher decrement of the tensile strength with higher wooden part failure mode.

Aging Characteristics of Bolt Pretension of Stress-laminated Timber (응력적층재의 볼트 압체력 경시변화)

  • Eom, Chang-Deuk;Lee, Sang-Joon;Kim, Kwang-Mo
    • Journal of the Korean Wood Science and Technology
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    • v.39 no.6
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    • pp.505-511
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    • 2011
  • In this study, it is carried out to analysis of the bolt pretension of the stress-laminated timber. Bolt pretension of stress-laminated timber was decreased by time. The loss of force is caused by moisture content, shrinkage of wood. After re-stressing the stress-laminated timber, the rate of force decrement was slowed significantly. To use of stress-laminated timber for the service, it is necessary to make an accurate estimate of force. It is clear that is different between actual value and predicted value changes by existing model for bolt pretension of stress-laminated timber. Accordingly, considering the time and the external environment, the development of prediction model is needed.

Effect of Carbonization Temperature on Hygric Performance of Carbonized Fiberboards

  • Lee, Min;Park, Sang-Bum;Lee, Sang-Min
    • Journal of the Korean Wood Science and Technology
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    • v.42 no.5
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    • pp.615-623
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    • 2014
  • Increases of public attention on healthy environment lead to the regulation of indoor air quality such as Clean Healthy House Construction Standard. This standard covers emission of total volatile organic compounds (TVOCs) (e.g., formaldehyde, benzene, and toluene), ventilation, and use of environmentally-friendly products or functional products. Moisture absorption and desorption abilities are a recommended functionality for improving indoor air quality. In this study, moisture absorption and desorption capacities of carbonized board from wood-based panels and other materials were determined by using UNT-HEAT-01 according to ISO 24358:2008. Pine had higher moisture absorption and desorption capacities ($49.0g/m^2$ and $35.3g/m^2$, respectively) than hinoki cypress, cement board, gypsum board, oriented strand board, and medium density fiberboard (MDF). The moisture absorption and desorption capacities differed considerably according to the wood species. After carbonization process at $400^{\circ}C$, the absorption and desorption ability of MDF increased to 38% and 60%, respectively. However, moisture absorption and desorption capacities decreased with increasing carbonization temperature, but they were still higher than original MDF. Therefore, it is suggested that carbonization below $600^{\circ}C$ can improve moisture absorption/desorption capacities.