• 제목/요약/키워드: Fragmentation index

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The Analysis Method of Landscape Fragmentation using Normalized Difference Vegetation Index (식생지수에 의한 경관파편화의 해석기법)

  • Jeong, Jong-Chul
    • Journal of the Korean Association of Geographic Information Studies
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    • v.2 no.3
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    • pp.16-22
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    • 1999
  • The various spatial structure of biological habitat has tighten relationship with biodiversity. Due to increasing of population, development of agriculture and urban structure, various change of landscape has became these days. These change of landscape has raised the decrease of habitat and landscape fragmentation. This paper summarizes research to analysis vegetation index according to P/A ratio, Shape Index, and Fractal dimension using Landsat Thematic Mapper(TM). The analysis of landscape fragmentation using NDVI(Normalized Difference Vegetation Index) 0.5~1 has the most profitable for detection of vegetation fragmentation. The analysis of vegetation index of Seoul and Kyunggi province has also showed that Fractal dimension has the most fragmentation index. In near future, time series analysis is needed for fragmentation of vegetation on the same area, and for various landuse of fragmentation analysis. These researches were carried out for preservation strategy of vegetation and biodiversity.

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Forest Fragmentation and its impacts : A review (산림파편화에 대한 국내·외 연구동향)

  • Kim, Eunyoung;Song, Wonkyong;Lee, Dong-Kun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.15 no.2
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    • pp.149-162
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    • 2012
  • Habitat loss and fragmentation are ongoing major anthropogenic impacts on landscapes, which can strongly affect ecosystems, populations and species. The studies on forest fragmentation have been progressed, but the studies on definition of forest fragmentation and their synthetic trend in South Korea still leaves much to be desired. Therefore we set the definition of forest fragmentation and reviewed the related papers. We can give a definition that forest fragmentation is not only a process of spatial landscape transformation, but also a process of ecosystem change by it. The trend of studies on forest fragmentation divided into two fields, landscape and ecosystem changes. Forest fragmentation caused by land change altered the composition and configuration of forest patches. Most studies related on that analyzed the change using landscape index. The effects of forest fragmentation on ecosystem subdivided into three fields : biodiversity, edge effects, and invasive species, but the studies in South Korea is short. The study on relations between forest fragmentation and ecosystem change is necessary to face the Convention on Biological Diversity in South Korea. In addition, the fundamental studies on biodiversity is important to mitigate against forest fragmentation.

Analysis of Ecological Fragmentation Improvement Effect from the Riverine Restoration (수변벨트 조성에 따른 하천 단절성 개선 효과 분석)

  • Kang, Hyeongsik;Park, Min Young
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.6B
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    • pp.387-397
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    • 2012
  • In this study, an ecological fragmentation improvement effect from different riverine ecobelt width was analyzed. The target river for this study is the Hongcheon river in Kangwondo. This section of 11 km among the Hongchenon river was reported to be seriously fragmented in the previous literatures. The Hongcheon river of 11 km was divided longitudinally into subsections of 1 km. The analysis through map and aerial photograph as well as field surveys were performed in 11 subsections(A-K). Using the fragmentation index, the connectivity fragmentation such as river bank, road, and land use and the ecological functional fragmentation were evaluated. The results showed that I-section has the highest fragmentation rate. The Hongcheon river in the present status without ecobelt was analyzed to has the fragmentation of 2nd rate from the mean fragmentation value of 11-subsections. Also, when the riverine ecobelt of 10 m-50 m was restored, the improvement effect of connectivity fragmentation was relatively small, while for the ecological fragmentation, the improvement effect of 12.4-25.1% was predicted. Also, the ecobelts of 10 m and 30 m were evaluated to have a relatively great improvement effect. Especially, for the ecobelt of 30m width, the fragmentation rate was mitigated form 2nd rate to 3rd rate.

A Numerical Study on the Rock Fragmentation by TBM Cutter Penetration (TBM 커터 관입에 의한 암석 파쇄의 수치해석적 연구)

  • 백승한;문현구
    • Tunnel and Underground Space
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    • v.13 no.6
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    • pp.444-454
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    • 2003
  • Rock fragmentation technique by cutter penetration has widely been used in the mechanical tunnel excavation. Microcracks propagate and interact because of locally concentrated high stress induced by cutter penetration. which is caused by heterogeneity of rocks. In this study Weibull distribution function and degradation index are used to consider the strength heterogeneity of a rock and the degradation of rock properties after failure. Through the numerical analyses, it is shown that the lateral pressure has an important influence on the rock fragmentation. In the single cutter penetration, large chips are formed as lateral pressure increase. The cutter spacing is also an important factor that affects the rock fragmentation in the double cutter penetration. The fragmentation efficiency of the double cutter penetration is better when cutter spacing is 70 mm than 40 mm and 100 mm. From the results, it is expected that this study can be applied to a TBM tunnel design by understanding of chipping process and mechanism of rock due to cutter penetration.

Apoptosis in the craniofacial tissues of irradiated growing rats

  • Heo Min-Suk;Choi Hang-Moon;Lee Sam-Sun;Choi Soon-Chul;Park Tae-Won
    • Imaging Science in Dentistry
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    • v.31 no.4
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    • pp.227-233
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    • 2001
  • Purpose: The purpose of this study was to investigate the apoptosis induction in tissues constituting the craniofacial region of growing rat by irradiation. Materials and Methods: The submandibular gland, brain, articular cartilage of condylar head, and calvarium were extracted from 20-day-old rats irradiated 10 Gy. Apoptosis of each tissue was examined by DNA fragmentation and estimated quantitatively using apoptotic index on TUNEL assay. Apoptotic index of each tissue was calculated by the equation for apoptotic cells/total cells × 1,000 on the images of confocal laser scanning microscopy. Apoptotic index was analyzed statistically according to the time lapse after irradiation on the tissues. Results : In the submandibular gland, apoptotic index was significantly increased from 6 hours after irradiation showing the highest value at 12 hours and decreased to the control level at 3 days after irradiation. In the brain, apoptotic index was abruptly reached to the maximum value at 6 hours after irradiation and decreased to the control level at 4 days after irradiation. Articular cartilage and calvarium showed no or little apoptotic signals. The results obtained by the apoptotic index accorded with that of DNA fragmentation. Conclusion : Radiation was closely related with the apoptosis of submandibular gland and brain but, not related with the apoptosis of the articular cartilage of condylar head and calvarium. The changes induced by radiation of the hard tissues would not be explained by apoptosis.

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The rock fragmentation mechanism and plastic energy dissipation analysis of rock indentation

  • Zhu, Xiaohua;Liu, Weiji
    • Geomechanics and Engineering
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    • v.16 no.2
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    • pp.195-204
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    • 2018
  • Based on theories of rock mechanics, rock fragmentation, mechanics of elasto-plasticity, and energy dissipation etc., a method is presented for evaluating the rock fragmentation efficiency by using plastic energy dissipation ratio as an index. Using the presented method, the fragmentation efficiency of rocks with different strengths (corresponding to soft, intermediately hard and hard ones) under indentation is analyzed and compared. The theoretical and numerical simulation analyses are then combined with experimental results to systematically reveal the fragmentation mechanism of rocks under indentation of indenter. The results indicate that the fragmentation efficiency of rocks is higher when the plastic energy dissipation ratio is lower, and hence the drilling efficiency is higher. For the rocks with higher hardness and brittleness, the plastic energy dissipation ratio of the rocks at crush is lower. For rocks with lower hardness and brittleness (such as sandstone), most of the work done by the indenter to the rocks is transferred to the elastic and plastic energy of the rocks. However, most of such work is transferred to the elastic energy when the hardness and the brittleness of the rocks are higher. The plastic deformation is small and little energy is dissipated for brittle crush, and the elastic energy is mainly transferred to the kinetic energy of the rock fragment. The plastic energy ratio is proved to produce more accurate assessment on the fragmentation efficiency of rocks, and the presented method can provide a theoretical basis for the optimization of drill bit and selection of well drilling as well as for the selection of the rock fragmentation ways.

Comparative studies on Tenderness and Characteristics of Protein Obtained from Various Carcass grade in Korean native Cow (도체등급별 한우육의 연도와 단백질특성에 대한 비교연구)

  • 문윤희;강세주
    • Journal of Life Science
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    • v.7 no.4
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    • pp.336-341
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    • 1997
  • This study was conducted to investigate the effects of carcass grade on the hardness, myofibrillar fragmentations index, protein extractability and Mg-ATPase activity of myofibril and actomyosin obtained from 1, 2, 3 and D carcass grade)subgrade) in Korean native cow. Proximate component, hardness, chewiness, myofibril fragmentation index, protein extractability and Mg-ATPase activity if myofibril or actomyosin were not significantly different between 1st and 2nd carcass grade loin. The hardness and chewiness of 2nd carcass grade loin's were significantly lower than 3th grade loin's, but the myofibril fragmentation index, sarcoplasmic protein extractability and Mg-ATPase activity of myofibril were higher. The myofibrillar protein extractability and Mg-ATPase activity of actomyosin obtained from 3th carcase grade loin's were significantly higher than D grade loin's, but the hardness, chewiness and stroma protein extractability were lower. In conclusion, the degree of toughness in Korean native cow's loin was not significantly different between 1st and 2nd grade, but 3rd and D carcass grade were significantly higher, regardless of before and after aging.

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Physico-chemical Properties for Utilization of Aging Index of Cold Storage Beef Tenderloin (냉장우육의 숙성도 지표로 활용하기 위한 물리화학적 특성)

  • 정인철;김미숙;신완철;문윤희
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.4
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    • pp.647-653
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    • 1997
  • To establish the index of aging stage for cold storage beef tenderloin, shear force value(SFV), Mg-ATPase activity, myofibrillar fragmentation index(MFI), myofibrillar fragmentation ratio(MFR) and appearance of 30KD(30KD) were measured as the parameters for the indices of aging stage. Aging index of air-packed beef tenderloin stored for 14 days at 3$^{\circ}C$ were useful in the order of SFV(r=-0.893)>MFR (r=0.863) >30KD(r=0.853)>MFI(r=0.814)>Mg-ATPase activity(г=0.804). Vacuum-packed beef tenderloin stored for 28 days at 3$^{\circ}C$ were useful in the order of MFR(r=0.880)>30KD(r=0.836). In case of the correlation between aging indices of air-packed beef tenderloin, MFR had relation with SFV, Mg-ATPase activity, MFI and 30KD. In case of the correlation between aging indices of vacuum-packed beef ten- derloin, MFR had relations with 30KD.

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Fragmentation Analysis of Daejeon City's Green Biotope Using Landscape Index and Visualization Method (경관의 지수화 및 시각화 기법을 활용한 대전광역시 녹지비오톱 파편화 분석)

  • Kim, Jin-Hyo;Ra, Jung-Hwa;Lee, Soon-Ju;Kwon, Oh-Sung;Cho, Hyun-Ju;Lee, Eun-Jae
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.19 no.3
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    • pp.29-44
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    • 2016
  • The purpose of this study is to quantitatively and visually analyze the degree of green biotope fragmentation caused by road construction and other development work using FRAGSTATS and GUIDOS tool. Moreover, linking of the endangered species research, we mapped "Biotope Fragmentation Map" of Daejeon-city. The findings of the study are summarized as follows: First, as the result of FRAGSTATS, landscape indices : number of patch(NP), mean patch size (MPS), edge length(TE), mean nearest neighbor distance(MNN), edge shape(LSI) showed meaningful change from fragmentation. Moreover, the result of GUIDOS analysis, middle core-small core-bridge-branch-edge-islet-perforation showed increase of area percentage without large core. Lastly, analysis result of 'Biotope Fragmentation Map' revealed that changing site of large core's size appeared eighteen-site and designated as the special protection area appeared forty-one site. As the result of the two data, overlapping areas that showed both change of core size and revealed special protection areas revealed four site. For example, five species of endangered species appeared on the NO. 4 site in 'Biotope Fragmentation Map'. The findings of this study as summarized above are considered to play an important role in basic data preventing green biotope fragmentation at the planned level from various development work.

Effects of Storage Period and Rechilling Process on Tenderness of Chilled or Frozen Beef (냉장 또는 동결우육에 있어서 저장기간과 재냉장이 연도에 미치는 영향)

  • 김미숙;문윤희
    • Food Science of Animal Resources
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    • v.18 no.3
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    • pp.216-223
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    • 1998
  • This study was conducted to investigate the effects of the tenderness for the vacuum chilled, the air-frozen or the rechilled Holstein beef loin. The vacuum packaged beef was stored at 1$^{\circ}C$ and the air-packaged beef was stored at -20$^{\circ}C$ for 60 days. The rechilled beef was restored for 3 days at 1$^{\circ}C$ by using the vacuum chilled or the air-frozen beef. Hardness and chewiness of the vacuum chilled beef were better than those of the air-frozen beef. Hardness and chewiness were improved significantly(p<0.05) after the 40 days storage for the vacuum chilled beef, but there was no significant improvement for the air-frozen beef during the 60 days storage. By the rechilling process, tenderness and myofibrillar fragmentation index of the vacuum chilled and air-frozen beef improved. Especially those were improved significantly(p<0.05) in the vacuum chilled beef after the 20 days storage, and in the air-frozen beef after the 40 and 60 days storage.

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