• 제목/요약/키워드: natural potential

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

  • Kim, Jeong-Un;Yang-Jai Yim
    • The Korean Journal of Ecology
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    • 제10권4호
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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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    • 제2권5호
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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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    • 제16권5호
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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.

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 (Estimation for Changes of Net Primary Productivity and Potential Natural Vegetation in the Korean Peninsula by the Global Warming)

  • Kim, Jeong-Un;Kil, Bong-Seop
    • The Korean Journal of Ecology
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    • 제19권1호
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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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북한산국립공원의 현존식생과 잠재자연식생 (Actual Vegetation Potential Natural Vegetation of Pukhansan National Park, Mid-western Korea)

  • 이은복
    • The Korean Journal of Ecology
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    • 제20권6호
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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
    • 대한의생명과학회지
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    • 제29권3호
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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.

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

  • 지영일;문유미
    • 한국재난정보학회 논문집
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    • 제16권3호
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    • pp.594-601
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    • 2020
  • 연구목적: 본 연구는 경기도 지역의 재난피해가능성불안 및 지각된 스트레스가 대피행동에 영향을 미치는 요인을 파악하는데 있다. 연구방법:가설검증을 위하여 다중회귀분석(Multiple Regression analysis), 연령, 지역별 재난피해가능성불안 간의 대응일치 유사성을 분석하였다. 연구결과: 안전취약계층피해 가능성불안과 재난시스템 붕괴피해가능성불안이 밀접한 위치에서 지각되는 것을 확인하였다. 지각된 스트레스에 재난시스템붕괴, 피난생활, 자연재해 등이 영향요인으로 확인되었다. 다음으로 대피행동에 스트레스와 자연재해가 영향을 미치는 요인으로 확인되었다. 결론: 자연재해피해가능성불안과 스트레스가 대피행동에 영향을 미치므로 스트레스 관리의 필요성을 확인하였다. 최근 들어 강우량을 통한 재해에서 경험하였듯이 재해의 피해가능성불안은 높아질 것으로 예측된다. 이를 관리하기 위해서는 예방차원의 계획과 심리적 관리가 중요함을 시사하였다.

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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    • 제75권3호
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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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    • 제2권3호
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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.

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

  • 김보묵;양금철
    • Ecology and Resilient Infrastructure
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    • 제4권2호
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    • pp.115-121
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    • 2017
  • 본 연구는 가야산국립공원을 대상으로 지리정보시스템(Geometric Information System, GIS)을 이용 식생분포에 영향을 미치는 요인들을 분석하여, 식생분포 확률을 기초로 가야산국립공원의 잠재자연식생을 추정하였다. 가야산국립공원의 현존식생조사 결과 128개의 군락이 분포하는 것으로 나타났다. 가야산국립공원의 고도, 경사, 사면방위, 지형지수, 연평균 온도, 온량지수, 잠재증발산량의 7개 요인을 중심으로 군락별 분포를 분석하였으며, 이를 바탕으로 분포확률을 추정하였다. 잠재자연식생의 분포확률이 0.3이상인 군락은 소나무군락의 출현확률이 55.80%로 가장 높았으며, 신갈나무군락이 44.05%, 상수리나무군락이 0.09%, 굴참나무군락이 0.06%로 나타났다. 식생의 분포에 영향을 주는 요인을 본 연구에서 제시한 요인으로 한정할 경우 가야산국립공원의 잠재자연식생은 신갈나무군락(43.1%)과 소나무군락(56.9%)이 나타날 것으로 예측되었다.