• Title/Summary/Keyword: natural potential

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Actual Vegetation and Potential Natural Vegetation of Seonunsan Area, Southwestern Korea (선운산 지역의 현존식생과 잠재자연식생)

  • Kim, Jeong-Un;Yang-Jai Yim
    • The Korean Journal of Ecology
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    • v.10 no.4
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    • pp.159-164
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    • 1987
  • The potential natural vegetation of Seonunsan area, southwestern Korea, was inferred from the actual vegetation. In previous two papers the plant communities of actual vegetation of the area is grouped into nine types; Quercus variabilis, Pinus densiflora, Carpinus tschonoskii, Quercus serrata, Camellia japonica (plantation), Quercus aliena, Pinus thunbergii, Zelkova serrata and Carpinus laxiflora forest. With the analysis of species richness, age structure and various informations on vegetation changes of the plant communities, two paths of late stage succession are suggested in climatic climax starting from Pinus densiflora forest in the area. One is through Quercus variabilis forest to Carpinus laxiflora forest in upper parts of the mountain and the other through Quercus aliena forest to Carpinus tschonoskii forest in lower parts of the mountain. With analysis of actual vegetation and the examination of informations including human activities in the area, the potential natural vegetation of the area was inferred. The potential natural vegetation of the area was mainly composed of Carpinus laxiflora, Carpinus tschonoskii, Pinus densiflora and Zelkova serrata forest. The actual vegetation map and potential natural vegetation map (scale, 1:25, 000) and other results from this study might be the useful data for the protection of natural vegetation and restoration of the current vegetation.

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Crevice Corrosion Resistance of Stainless Steels in Natural Sea Water with different Post Welding Treatment

  • Lee, Y.H.;Kim, Y.H.;Kim, H.
    • Corrosion Science and Technology
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    • v.2 no.5
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    • pp.219-224
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    • 2003
  • Crevice corrosion of stainless steels in natural seawater was investigated for several post weld treatments; as-annealed, as-welded, pickled, and ground. The results confirmed the effect of the biofilm on the cathodic reaction leading to an ennoblement of the rest potential. The degree of ennoblement of corrosion potential depends on the surface finish. As-annealed and pickled samples show stable corrosion potential approaching to 200 ~ 300 mV (SCE) while as-welded and ground samples show the fluctuating corrosion potential. This points to a situation where there are conflicting effects determining the trend in free corrosion potential. Crevice corrosion initiation will tend to pull the free corrosion potential in the active direction, whereas the presence of biofilm will tend to ennoble corrosion potential. There was no visible attack on UNS S31803, S32550, and 2205W. Therefore, those stainless steel grades appeared to be resistant to crevice corrosion in natural seawater on condition of weld metal.

Potential Use of Biopolymer-based Nanocomposite Films in Food Packaging Applications

  • Rhim, Jong-Whan
    • Food Science and Biotechnology
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    • v.16 no.5
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    • pp.691-709
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    • 2007
  • Concerns on environmental waste problems caused by non-biodegradable petrochemical-based plastic packaging materials as well as consumer's demand for high quality food products has caused an increasing interest in developing biodegradable packaging materials using annually renewable natural biopolymers such as polysaccharides and proteins. However, inherent shortcomings of natural polymer-based packaging materials such as low mechanical properties and low water resistance are causing a major limitation for their industrial use. By the way, recent advent of nanocomposite technology rekindled interests on the use of natural biopolymers in the food packaging application. Polymer nanocomposites, especially natural biopolymer-layered silicate nanocomposites, exhibit markedly improved packaging properties due to their nanometer size dispersion. These improvements include increased mechanical strength, decreased gas permeability, and increased water resistance. Additionally, biologically active ingredients can be added to impart the desired functional properties to the resulting packaging materials. Consequently, natural biopolymer-based nanocomposite packaging materials with bio-functional properties have huge potential for application in the active food packaging industry. In this review, recent advances in the preparation and characterization of natural biopolymer-based nanocomposite films, and their potential use in food packaging applications are addressed.

Estimation for Changes of Net Primary Productivity and Potential Natural Vegetation in the Korean Peninsula by the Global Warming (地球 溫暖化에 따른 韓半島의 純一次生産力과 潛在自然植生의 變化 推定)

  • Kim, Jeong-Un;Kil, Bong-Seop
    • The Korean Journal of Ecology
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    • v.19 no.1
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    • pp.1-7
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    • 1996
  • The net primary productivity and potential natural vegetation in the Korean peninsula in the 21st century were estimated by the Miami model and thermal climate, respectively, based on 148 meteorological data sets. In the 21st century, the distribution range of the net primary produtivity in the Korean peninsula was estimated as 1,050 g $DM{\cdot}m^{-2}{\cdot}yr^{-1}~2,050g\;DM\cdot m^-2\cdot yr^{-1}.\; These\; values\; increased\; by\; 200g\; DM\cdot m^{-2}\cdot yr^{-1}\;on\;northern\;part\;and\;400g\; DM\cdot m^{-2}\cdot yr^{-1}$ on southern part compared with that of the present century. The potential natural vegetation in the Korean peninsula in the 21st century will change into the followings:coniferous forest on Mt. Paektu area, deciduous broadleaf forest on northern part, and evergreen broadleaf forset on southern part.

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Actual Vegetation Potential Natural Vegetation of Pukhansan National Park, Mid-western Korea (북한산국립공원의 현존식생과 잠재자연식생)

  • 이은복
    • The Korean Journal of Ecology
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    • v.20 no.6
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    • pp.439-450
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    • 1997
  • The potential natural vegtation of the Pukhansan National Park area, mid-western Korea, was inferred from the actual vegetation. With the phytosociological classification and field surveys, the actual vegetation map of the park area was made on a scale of 1:25, 000, including fourteen communities. By the analyses of the species diversity, the age structure, the human interferences and various informations on vegetation changes, two pathways of late stage succession from Pinus densiflora forests to the climatic climax were suggested. One is from Quercus serrata forests to Q. mongolica forests throughout the mountain and the other, from Q. variabilis or Q. acutissima forests to Carpinus laxiflora forests in lower parts. Considering the vegetation changes, the potential natural vegetation of the park area mainly composed of Q. mongolica, C. laxiflora, P. densiflora and Zelkova serrata forest as the climatic and/or edaphic climax was inferred.

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Natural Products as Potential Therapeutic Strategies for Parkinson's Disease

  • Hae-Rim Cha;Mi-Ran Lee;Hyun-Jeong Cho
    • Biomedical Science Letters
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    • v.29 no.3
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    • pp.121-129
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    • 2023
  • Parkinson's disease (PD) is a progressive neurodegenerative disorder that affects millions of people worldwide. The conventional treatment model for PD have harmful side effects, such as dyskinesia, hallucinations, nausea, and fatigue, and are expensive. As a result, natural products derived from medicinal herbs, fruits, and vegetables have emerged as potential therapeutic strategies for PD. These natural products have been traditionally used to treat various diseases and have been shown to possess anti-oxidative and anti-inflammatory properties, as well as inhibitory roles in protein misfolding, mitochondrial homeostasis, neuroinflammation and other neuroprotective processes. In addition, they have fewer side effects and are generally less expensive than conventional drugs. It also discusses the limitations of current treatments and the potential of natural remedies derived from plants to treat PD in new ways or as supplements to existing treatments. The multifunctional mechanisms of medicinal plants that may be utilized to treat PD are also discussed, including the modulation of neurotransmitter systems, the enhancement of neurotrophic factors, and the inhibition of apoptosis. While more research is needed to fully understand their mechanisms of action and efficacy, natural products have the potential to provide safer and more effective treatment options for patients with PD.

Factors Affecting Potential Disaster Damage and Perceptible Stress Influencing Evacuation Behavior (재난피해가능성불안 및 지각된 스트레스가 대피행동에 영향을 미치는 요인)

  • JI, Youngil;Moon, YooMi
    • Journal of the Society of Disaster Information
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    • v.16 no.3
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    • pp.594-601
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    • 2020
  • Purpose: The purpose of the present study was to identify factors affecting anxiety about disaster damage potential in Gyonggi-do and evacuation behavior that influences evacuation behavior. Method: Multiple regression analysis was performed to test the hypothesis and to analyze the influence of anxiety about disaster damage potential and perceived stress, and analyzed similarity in correspondence between age and anxiety about disaster damage potential. Results: The anxiety about disaster damage potential of a group vulnerable to safety and anxiety about disaster damage potential of disaster system collapse were perceived in close proximity. Disaster system collapse, evacuation life, and natural disasters were found to be factors affecting perceived stress. Stress and natural disasters were found to be influencing factors on evacuation behavior. Conclusion: The necessity of managing stress was confirmed since anxiety about natural disaster damage potential and stress affect evacuation behavior. The recent experiences of heavy rain disasters indicate that the anxiety about disaster damage potential is expected to increase. The findings also indicate the importance of preventive planning and psychological management to manage the anxiety about disaster damage potential.

Multi-potential capacity for reinforced concrete members under pure torsion

  • Ju, Hyunjin;Han, Sun-Jin;Kim, Kang Su;Strauss, Alfred;Wu, Wei
    • Structural Engineering and Mechanics
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    • v.75 no.3
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    • pp.401-414
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    • 2020
  • Unlike the existing truss models for shear and torsion analysis, in this study, the torsional capacities of reinforced concrete (RC) members were estimated by introducing multi-potential capacity criteria that considered the aggregate interlock, concrete crushing, and spalling of concrete cover. The smeared truss model based on the fixed-angle theory was utilized to obtain the torsional behavior of reinforced concrete member, and the multi-potential capacity criteria were then applied to draw the capacity of the member. In addition, to avoid any iterative calculation in the existing torsional behavior model, a simple strength model was suggested that considers key variables, such as the effective thickness of torsional member, principal stress angle, and strain effect that reduces the resistance of concrete due to large longitudinal tensile strain. The proposed multi-potential capacity concept and the simple strength model were verified by comparing with test results collected from the literature. The study found that the multi-potential capacity could estimate in a rational manner not only the torsional strength but also the failure mode of RC members subjected to torsional moment, by reflecting the reinforcing index in both transverse and longitudinal directions, as well as the sectional and material properties of RC members.

Bamboo Distribution Map for Planning the Development of Tourism Potential in Boon Pring Andeman Area

  • Farah, Devy Atika;Dharmawan, Agus;Novianti, Vivi
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.2 no.3
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    • pp.144-152
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    • 2021
  • Sanankerto is one of pilot projects for tourism villages in Indonesia due to its natural tourism potential with a 24-ha bamboo forest located in Boon Pring Andeman area. However, the distribution of existing bamboo has never been identified or mapped. Thus, the mana gement is facing difficulty in planning and developing tourism potential as well as spatial management in the area. Therefore, the objectives of this study were to identify and analyze the structure of bamboo vegetation in the Boon Pring Tourism village an d to perform vegetation mapping. The type of research was descriptive exploratory with a cluster sampling technique (i.e., a two-stage cluster) covering an area of ± 10 ha. Bamboo vegetation analysis was performed by calculating diversity index (H'), evenness index (E), and Species Richness index (R). Data were collected through observation and interviews with local people and the manager to determine zonation division. Mapping of bamboo vegetation based on zoning was processed into thematic maps using ArcG is 10.3. Micro climatic factors were measured with three replications for each sub -cluster. Data were analyzed descriptively and quantitatively. Nine species of bamboo identified. Diversity, evenness, and species richness indices differed at each location. Activities of local communities, tourists, and manager determined the presence, number, and distribution of bamboo species. These bamboo distribution maps in three zoning (utilization, buffer, and core) can be used by manager for planning and developing natural tourism potential.

Simulation Map of Potential Natural Vegetation in the Gayasan National Park using GIS (지리정보시스템을 이용한 가야산국립공원의 잠재자연식생 추정)

  • Kim, Bo-Mook;Yang, Keum-Chul
    • Ecology and Resilient Infrastructure
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    • v.4 no.2
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    • pp.115-121
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    • 2017
  • This study estimated potential natural vegetation in Gayasan National Park through the occurrence probability distribution by using geographic information system (GIS). in Gayasan National Park. Correlation and factor analysis were analyzed to estimate probability distribution. The presence of the Gaya National Park Vegetation survey results showed that 128 communities were distributed. The analyzed relationship between actual vegetation and distribution factors such as elevation, aspect, slope, topographic index, annual mean temperature, warmth index and potential evapotranspiration in Gayasan national park. The probability distribution of potential natural vegetation communities at least 0.3 odds were the advent of Pinus densiflora communities with the highest 55.80%, Quercus mongolica community is 44.05%, 0.09% is Quercus acutissima communities, Quercus variabilis communities are found to be 0.06%. If you want to limit the factors that affect the distribution of vegetation by factors presented in this study, the potential natural vegetation of the Gaya National Park was expected to appear in Quercus mongolica community (43.1%) and Pinus densiflora communities (56.9%).