• Title/Summary/Keyword: TOTAL COVERAGE

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Vegetation Structure and Succession of Highway Cutting-slope Area (고속도로 절토비탈면의 식생구조와 천이)

  • Song, Hokyung;Jeon, Giseong;Lee, Sanghwa;Kim, Namchoon;Park, Gwansoo;Lee, Byungjun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.8 no.6
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    • pp.69-79
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    • 2005
  • This study was carried out to select proper species for early stage replantation in highway cut-slope area. In highway cut-slope area, sample plots of 106 were selected, and their vegetations and environmental factors were investigated. 1. We found total 172 species in the 106 cutting area of highway. The species of high frequency of highway cut-slope were found in the order of Lespedeza bicolor, Artemisia princeps var. orientalis, Festuca arundinacea, Erigeron annuus, Lespedeza cuneata, Lactuca indica var. laciniata, Eragrostis curvula, Dactylis glomerata, Oenothera lamarckiana, Wistaria floribunda, Humulus japonica, Commelina communis, Miscanthus sinensis, Pueraria thunbergiana, Pinus densiflora, etc. 2. The average vegetation coverage was over 90% in the study sites and the average coverage was 91.4% in the total cut-slope area. The species of high coverage of highway cut-slope area were found in the order of Festuca arundinacea, Eragrostis curvula, Lespedeza bicolor, Wistaria floribunda, Lespedeza cuneata, Dactylis glomerata, Artemisia princeps var. orientalis, Humulus japonica, Pueraria thunbergiana, Robinia pseudoacacia, Poa pratensis, Medicago sativa, Festuca ovina, Pinus densiflora, Parthenocissua tricuspidata, etc. 3. The total coverage in the foreign plants of Festuca arundinacea, Eragrostis curvula, Dactylis glomerata, Poa pratensis, Medicago sativa, Coreopsis drummondii and native plants of Lespedeza bicolor, Wistaria floribunda, Lespedeza cuneata, Amorpha fruticosa, Indigofera pseudotinctoria, Lespedeza cyrtobotrya were 57.52%. That is, the ecological succession of native herbs and parachute shrubs have delayed because the afforested plants occupy 57.52%. In future, the coverage of foreign herbs have to reduce, and the coverage of the native herbs and parachute shrubs must be increased. 4. The native seed of Artemisia sp., Miscanthus sinensis, Smilax china, Pueraria thunbergiana, Rubus crataegifolius, Rubus parvifolius, Pinus densiflora, Rhus chinensis, Albizzia julibrissin, Rhododendron mucronulatum, Clematis apiifolia, Zanthoxylum schinifolium, Prunus sargentii could be added in the seedling of the temperate south zone highway with the used seeds. The native seed of Artemisia sp., Miscanthus sinensis, Rubus crataegifolius, Rhododendron mucronulatum, Weigela subsessilis, Stephanandra incisa, Rhus chinensis, Pinus densiflora, Salix koreensis, Cocculus trilobus, Populus alba, Spiraea prunifolia for. simpliciflora, Clematis apiifolia, Lindera obtusiloba, Quercus serrata, etc., could be added in the seedling of the temperate middle zone highway with the used seeds. 5. We have some recommendation. The native plants have to growth in the highway cut-slope area instead of foreign plants to have good environmental ecology. The role of the foreign plants should be the plant for the initial several years in the highway cut-slope area. And, the native plants should growth in the next season. 6. We should protect shrubs and trees in the highway slope area because shrubs and trees can be more helpful in stabilizing of the slope area than herbs.

Changing of Vegetation Coverage through Elapsed Years on Cutting Slope in Forest Roads (시간경과에 따른 임도 절토비탈면의 식생피복도 변화)

  • Jeon, Kwon-Seok;Ma, Ho-Seop
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.7 no.3
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    • pp.14-25
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    • 2004
  • The purpose of this study was investigated to the change of vegetation coverage by elapsed years on the cut slope of forest road in Jinju-si. The results obtained could be summarized as follows; The plant coverage on the cut slope of forest road was decreased hastily in first and second year after seeding. The plant coverage on the cut slope of forest road was increased as growth of seed-sprayed from third year. But the plants were began to competition with between sprayed seeds and invaded plants from third to fifth year after seed-spray. The numbers of invading plants were gradually increased as 581 individuals from sixth year after seed-spray. The cut slopes of the forest roads turned to a good site condition for growing of invasion plants. And also the total coverage on cut slope of forest roads by invading of surrounding plants was increased more. It showed that plant invasion on cut-slopes of forest roads would be mostly influenced by surrounding plants. The number of surrounding plants on the cut-slopes of forest roads was 59 species, and the number of invading plants showed 65 species. The invading species were high in order of Boehmeria tricuspis, Oplismens undulatifolius, Miscanthus sinensis var. purpurascens, Erechtites hieracifolia and Artemisia princeps var. Orientalis In the stepwise regression analysis, main factors affecting the coverage of vegetation on the cut-slopes of forest road showed in order of elapsed years, gravel contents(30~50%), middle, sandy loam, sandy clay-loam, soil hardness, aspect(NS), concave(凹) type and gravel contents(15~30%).

Collaborative Stepwise Movement of Mobile Sensor Nodes for Energy Efficient Dynamic Sensor Network Coverage Maintenance (모바일 센서노드들의 협동형 단계적 이동기법 기반의 에너지 효율적인 동적 센서네트워크 커버리지 관리)

  • Han, Ngoc-Soc;Kim, Seong-Whan
    • The KIPS Transactions:PartC
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    • v.16C no.4
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    • pp.535-542
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    • 2009
  • Wireless Sensor Network (WSN) is a wireless network consisting of spatially distributed autonomous devices, using sensors to cooperatively monitor physical or environmental conditions. WSNs face the critical challenge of sustaining long-term operation on limited battery energy. Coverage maintenance has been proposed as a promising approach to prolong network lifetime. Mobile sensors equipped with communication devices can be leveraged to overcome the coverage problem. In this paper, we propose a stepwise movement scheme using perimeter coverage property for the coverage maintenance problem. In our scheme, each sensor monitors neighboring dead nodes, determines vulnerable node (i.e. dead node which makes uncovered area), computes the center of uncovered area HC, and makes a coordinated stepwise movement to compensate the uncovered area. In our experimental results, our scheme shows at least 50 % decrease in the total moving distance which determines the energy efficiency of mobile sensor.

Normalized Cross-Correlations of Solar Cycle and Physical Characteristics of Cloud

  • Chang, Heon-Young
    • Journal of Astronomy and Space Sciences
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    • v.36 no.4
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    • pp.225-234
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    • 2019
  • We explore the associations between the total sunspot area, solar north-south asymmetry, and Southern Oscillation Index and the physical characteristics of clouds by calculating normalized cross-correlations, motivated by the idea that the galactic cosmic ray influx modulated by solar activity may cause changes in cloud coverage, and in turn the Earth's climate. Unlike previous studies based on the relative difference, we have employed cloud data as a whole time-series without detrending. We found that the coverage of high-level and low-level cloud is at a maximum when the solar north-south asymmetry is close to the minimum, and one or two years after the solar north-south asymmetry is at a maximum, respectively. The global surface air temperature is at a maximum five years after the solar north-south asymmetry is at a maximum, and the optical depth is at a minimum when the solar north-south asymmetry is at a maximum. We also found that during the descending period of solar activity, the coverage of low-level cloud is at a maximum, and global surface air temperature and cloud optical depth are at a minimum, and that the total column water vapor is at a maximum one or two years after the solar maximum.

A suggestion of health insurance for children (소아 영역의 건강보험제도 개선안)

  • Eun, Baik-Lin
    • Clinical and Experimental Pediatrics
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    • v.51 no.4
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    • pp.339-342
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    • 2008
  • The Korean Health Insurance (KHI) has been introduced since 1977 and it took only 12 years that KHI had accomplished the total coverage of Korean population. The remarkable success of KHI can be compared with other OECD countries which had taken some 30 years to over 100 years to establish the total coverage of the population. Life expectancy at birth and the infant mortality rate in Korea in 2005 both surpassed the average figures of the OECD countries, The main reason for the success of KHI can be delineated with the three characteristics in KHI development; low premiums, low benefits, and low fee-schedule charges. However, these three characteristics of KHI, which had been the key for the rapid development of the system, have become terrible disadvantages for the stable development of KHI. The dissatisfaction and discontent of health care providers are ever increasing. The population is reluctant to pay more premiums though it seems essential for the better care coverage. The health care system has been heavily distorted toward high technology-oriented expensive care. There should be several factors seriously tackled for the secure development of KHI in the future. This paper will review a brief history of KHI development, and I would like to make a suggestion of health insurance for children.

Selection of Korean General Vocabulary for Machine Readable Dictionaries (자연언어처리용 전자사전을 위한 한국어 기본어휘 선정)

  • 배희숙;이주호;시정곤;최기선
    • Language and Information
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    • v.7 no.1
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    • pp.41-54
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    • 2003
  • According to Jeong Ho-seong (1999), Koreans use an average of only 20% of the 508,771 entries of the Korean standard unabridged dictionary. To establish MRD for natural language processing, it is necessary to select Korean lexical units that are used frequently and are considered as basic words. In this study, this selection process is done semi-automatically using the KAIST large corpus. Among about 220,000 morphemes extracted from the corpus of 40,000,000 eojeols, 50,637 morphemes (54,797 senses) are selected. In addition, the coverage of these morphemes in various texts is examined with two sub-corpora of different styles. The total coverage is 91.21 % in formal style and 93.24% in informal style. The coverage of 6,130 first degree morphemes is 73.64% and 81.45%, respectively.

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Band engineering of bilayer graphene by metal atoms: First-principles calculations

  • Oh, D.H.;Shin, B.G.;Ahn, J.R.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.08a
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    • pp.267-267
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    • 2010
  • The continuous change in the electronic band structure of metal-adsorbed bilayer graphene was calculated as a function of metal coverage using first-principles calculations. Instead of modifying the unit cell size as a function of metal coverage, the distance between the metal atoms and bilayer graphene in the same $2{\times}2$ unit unit cell was controlled to change the total charges transferred from the metal atoms to bilayer graphene. The validity of the theoretical method was confirmed by reproducing the continuous change in the electronic band structure of K-adsorbed epitaxial bilayer graphene, as shown by Ohta et al. [Science 313, 951 (2006)]. In addition, the changes in the electronic band structures of undoped, n-type, and p-type bilayer graphene were studied schematically as a function of metal coverage using the theoretical method.

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Temporal Variations in Seaweed Biomass and Coverage in Korean Coasts: Ongdo, Chungnam

  • Wan, Xiao Qin;Park, Hyang-Ha;Yoo, Hyun-Il;Choi, Han-Gil
    • Fisheries and Aquatic Sciences
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    • v.12 no.2
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    • pp.130-137
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    • 2009
  • Temporal variations of seaweed biomass and coverage were seasonally examined at Ongdo in the Yellow Sea, Korea from August 2006 to April 2008. Average seaweed biomass was 245.79 g/$m^2$ in wet weight and coverage was 16.49% with seasonal variations from 13.97% in spring to 18.55% in autumn. Seaweeds were distributed across the shore gradient from the high intertidal to 10m depth in the subtidal zone. Biomass was always higher in the subtidal zone (310.24 g/$m^2$) than in the intertidal zone (181.35 g/$m^2$). Of total seaweed biomass, 76.52% (first year) and 80.32% (second year) occurred from the low intertidal zone, down to depth of 1 to 5m. Gelidium amansii had the highest importance value and biomass, and sub dominant species were Chondrus ocellatus and Chondria crassicaulis. Coarsely-branched seaweeds comprised the highest proportion of biomass (214.84 g/$m^2$, or 87.41% of the total biomss). Seasonal variations in algal biomass were largely explained by fluctuations in the biomass of coarsely-branched and thick-leathery forms. In conclusion, seaweed biomass of Ongdo shore was very low because of perennial G. amansii showing low biomass as compared to kelp or Sargassum spp. However, these results indicate Ongdo is good place to grow seaweeds because coarsely-branched form seaweeds including G. amansii are dominant at unpolluted and clean environment.

Local and regional steppe vegetation palatability at grazing hotspot areas in Mongolia

  • Amartuvshin, Narantsetsegiin;Kim, Jaebeom;Cho, Nanghyun;Seo, Bumsuk;Kang, Sinkyu
    • Journal of Ecology and Environment
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    • v.46 no.1
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    • pp.76-84
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    • 2022
  • Background: Climate and livestock grazing are key agents in determining current Mongolian steppe vegetation communities. Together with plant coverage or biomass, palatability of steppe community is regarded as a useful indicator of grassland degradation, in particular, at grazing hotspots in arid and semi-arid grasslands. This study analyzed relationships between livestock grazing pressure and steppe vegetation palatability at three summer pastures with different aridity (dry, xeric, and mesic) and livestock numbers (1,100, 1,800, and 4,100 sheep units, respectively). At each site, it was surveyed coverage, biomass, and species composition of different palatability groups (i.e., palatable [P], impalatable [IP], and trampling-tolerant [TT]) along a 1-km transect from grazing hotspots (i.e., well) in every July from 2015 to 2018. Results: In results, total vegetation coverage increased with wetness, 7 times greater at mesic site than dry one in averages (33.1% vs. 4.5%); biomass was 3 times higher (47.1 g m-2 vs. 15.7 g m-2). Though P was the dominant palatability group, the importance of IP in total coverage increased with aridity from mesic (0.6%) to dry (40.2%) sites. Whereas, TT increased with livestock numbers across sites. Locally, IP was observed more frequently near the wells and its spatial range of occurrence becomes farther along the transects with aridity across sites from mesic (< 100 m) to dry (< 700 m from the well). Conclusions: Our results showed that the importance of IP and its spatial distribution are different at both local and regional scales, indicating that the palatability parameters are sensitive to discern balance between selective-grazing demand and climate-driven foraging supply in Mongolian rangelands.

Complete Coverage Path Planning for Multi-Robots (멀티로봇에 대한 전체영역 경로계획)

  • Nam, Sang-Hyun;Shin, Ik-Sang;Kim, Jae-Jun;Lee, Soon-Geul
    • Journal of the Korean Society for Precision Engineering
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    • v.26 no.7
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    • pp.73-80
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    • 2009
  • This paper describes a path planning algorithm, which is the minimal turning path based on the shape and size of the cell to clean up the whole area with two cleaning robots. Our method divides the whole cleaning area with each cell by cellular decomposition, and then provides some path plans among of the robots to reduce the rate of energy consumption and cleaning time of it. In addition we suggest how to plan between the robots especially when they are cleaning in the same cell. Finally simulation results demonstrate the effectiveness of the algorithm in an unknown area with multiple robots. And then we compare the performance index of two algorithms such as total of turn, total of time.