• Title/Summary/Keyword: Disturbed area

Search Result 205, Processing Time 0.028 seconds

Analysis of the Basement Structure of Noeun Waste Landfill Site Using a Refracted Elastic Wave Tomography Survey (탄성파 굴절법 토모그래피 방법을 이용한 노은 폐기물 매립장의 지반 구조 분석)

  • Kim, Jun-Kyoung
    • Journal of the Korean earth science society
    • /
    • v.27 no.4
    • /
    • pp.425-432
    • /
    • 2006
  • A seismic tomography using refraction waves is applied to provide information on depth of basement rocks and leachate distribution of the Noeun waste landfill site for the stage of preliminary environmental survey. This method is generally applied to civil and environmental areas. Three lines, apparently perpendicular to the potential leachate flow direction in this site, were installed to investigate the waste landfill site in pseudo three dimensional geometry. The results show that the site is composed of 3 layers and depth of basement becomes shallower at the upstream area of the landfill site than that of the downstream area. Moreover, some parts of the second layer and the basement at the down stream area are partially infiltrated by the leachate, probably related to the disturbed distribution of the different velocity materials within the second layer. In Conclusion, refraction wave tomography is found to be one of the most efficient way to investigate waste landfill site.

Hydrogeological Characteristics of Seawater Intrusion in the Coastal Area (임해지역 주변에서의 해수침투특성)

  • 김천수;김경수;배대석;송승호
    • Journal of the Korean Society of Groundwater Environment
    • /
    • v.4 no.2
    • /
    • pp.61-72
    • /
    • 1997
  • With increasing activities for groundwater withdrawal and for the construction of underground cavern in the coastal areas, the seaward flow of groundwater has been disturbed or even reversed, resulting in seawater intrusion in aquifers. This phenomenon would be attributed to the freshwater contamination and the corrosion of steel materials. The hydrogeological and geochemical investigations have performed to characterize the seawater intrusion into the underground caverns located in the coastal area. Assumimg the inland aquifer as unconfined one, we have found out that the theoretical interface of freshwater-seawater is far different from the pathways identified. In the study site, the main pathways of seawater intrusion into the underground cavern are characterized as the sub-horizontal fractures (zones). The seawater intrusion in granitic terrane would depend mainly on the characteristics of conductive fracture system developed along the coastal area.

  • PDF

Atherogenic Risk Stratification According to Changes in the Geometrical Shape of the Coronary Artery (관상동맥의 기하학적 형상변화에 따른 동맥경화 위험도)

  • Suh, Sang-Ho;Park, Jun-Gil;Roh, Hyung-Woon;Lee, Byung-Kwon;Kwon, Hyuck-Moon
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.34 no.10
    • /
    • pp.893-899
    • /
    • 2010
  • A previous study showed that hemodynamics is correlated with stenosis in the coronary artery. The flow characteristics and the distributions of the hemodynamic wall parameters in the coronary artery are investigated under physiological flow condition. The present study also aims to establish the mechanism of the generation of atherosclerosis by analyzing the hemodynamic variables in the coronary artery where atherosclerosis frequently occurs. The stenosis phenomena due to atherosclerosis are related to not only the biochemical reaction between blood and blood vessels but also the hemodynamic factors sush as flow separation and oscillatory wall shear stress. As the bifurcated angle increases, the size of the recirculation area that appears in the cross section increases and disturbed flow is observed in this area. We speculate that this area is the starting point of atherosclerosis in the coronary artery.

Research on the Utilization of the Native Plants in Restoration of Stream-Side in Rural Areas (농촌마을 소하천변 식생복원을 위한 자생식물 선정에 관한 연구)

  • Kang, Bang-Hun;Lee, Sang-Hwa
    • Journal of Korean Society of Rural Planning
    • /
    • v.12 no.4 s.33
    • /
    • pp.83-88
    • /
    • 2006
  • Recently, management and restoration efforts using the plants promote the disturbed habitats such as a set-asides or field boundaries. But, side effects are coming out because of using the exotic plants in restoration process. This study was conducted to select the native plant species used for restoration through the vegetation survey and plant community analysis at small stream-side in rural villages. We surveyed at two small stream-sides in open field and high land area in 2005 as a case study. Total 126 species was found at small stream side in open field area. As the result of important value' calculation, Persicaria thunbergii 23.0%, Humulus japonicus 18.6%, Phragmites communis 4.4%, Bromus japonicus 4.2%, and Rosa multiflora 3.4% were in the order of important value. Total 92 species were found at small stream side in high land area. As the result of important value' calculation, Dactylis glomerata 16.1%, Artemisia princeps var. orientalis 11.0%, Persicaria thunbergii 10.9%, Humulus japonicus 9.3%, Phragmites japonica 5.2% and Phragmites communis 3.5% were in the order of important value. We selected some plant species to use in restoration after due consideration of problems of exotic plant and high coverage and density species, and ecological process; Persicaria thunberii, Phragmites communis, Bromus japonicus, Rosa multiflora, Equisetum arvense, Digtaria sanguinalis, Impatiens textori, and Artemisia princeps var. orientalis in open field stream-side, and Artemisia princeps var. orientalis, Persicaria thunbergii, Phragmites japonica, Phragmites communis, Artemisia selengensis, Panicum bisulcatum, Rorippa indica, and Equisetum arvense at hghland stream-side. We will verify the selected native plants and plan the utilization of the native plants in restoration at stream-side in rural village.

A Fundamental Study on Village Planning in the Reclaimed Area -A Case Study of Farming Villages in Deuk Ryang Reclaimed Area- (간척지 농촌취락계획을 위한 기초연구 -전남 보성군 득량간척지 농촌취락의 사례연구-)

  • 최수영;이원철;한경수;황한철
    • Magazine of the Korean Society of Agricultural Engineers
    • /
    • v.35 no.2
    • /
    • pp.33-42
    • /
    • 1993
  • In order to obtain the basic information for the optimal settlement planning in the reclaimed area, various existing settlement conditions on reclaimed farming village were analysed through a case study of in-and-round farming villages in Deuk Ryang Reclaimed Area. By comparison study between in-and-around villages, the allocation policy of farming settlement in the samll and medium scale area was proposed. The results obtained in this study were as follows ; 1.The population structure of the inner village(Ansim village) had become worse than the around village during 1976~1981 period from the viewpoint of total and female emigration ratios. Especially, the originally unbalanced sex ratio of Ansim village had worsen to the unacceptable ratio of 1.5 : 1(male : female). Therefore, the structural stability of the population should be carefully improved in the newly reclaimed farming villages by the systematic long-term controlling machanism.2.The farming status of Ansim village was much lower than the around villages viewing of the cultivated acreage and agricultural machinery stock Therefore, the continuous and intensive governmental support different from the existing farming area should be required for the settling of reclaimed farming. 3. The regularity of the village site as a planned village, though pursed in the first phase of village construction, had been severely disturbed inflowing of squatters. Recently, there are increasing vaccant houses in the village, and the level of living amenities and personal mobility of Ansim village are much lower than the around village. So, now, the physical structure of the village should be improved to the level of village reconstruction or new village construction. 4. The cultivated area of Ansim village leans to the south side which would be unfavoured by the farmers of the around villages, while its distributing pattern should be concentric around the village site. This phenomenon disturbs the central fuction of the planned farming village. In this respect, role assignment, relationship and balance of competence in farming activities should be planned between in-and-around villages in the reclaimed area from the initial stage. 5. Putting together the above results in this study, the farming and living conditions of Ansim village threaten its existence as a planned new farming village in the reclaimed area. And, so, the full scale reconstruction of village structure, including moving to the new site, should be designed as soon as possible. Although further many studies should be carried out, it would be sure that the new village planning should be reconsidered in the small and-medium scale reclamation works.

  • PDF

Spatial distribution of vegetation along the environmental gradient on the coastal cliff and plateau of Janggi peninsula (Homigot), southeastern Korea

  • Jung, Song Hie;Kim, A Reum;Lim, Bong Soon;Seol, Jae Won;Lee, Chang Seok
    • Journal of Ecology and Environment
    • /
    • v.43 no.2
    • /
    • pp.117-128
    • /
    • 2019
  • Background: Cliffs are a major plant habitat around the coastal area, but in contrast to sand dunes and salt marshes, they have been little investigated in Korea. There are simple descriptions of cliff vegetation in studies on island vegetation, but there is no published paper, which addressed sea cliff vegetation synthetically. Furthermore, the coastal area where this study was carried out was designated as a conservation reserve. Even though, this area is exposed to intense recreational use such as trekking in these days. This study aims to clarify spatial distribution and structure of vegetation along the environmental gradient on coastal cliff and plateau in the Janggi peninsula (Homigot) located on southeastern Korea. Further, this study has also another objective to prepare a restoration plan to protect this conservation reserve from intense human disturbance. Results: Landscape elements were arranged in the order of sea cliff risen directly on the sea, seashore, coastal cliff, and plateau covered with relatively deep soil in a coastal area of the Janggi peninsula (Homigot), southeastern Korea. Vegetation was sampled at 59 plots arranged from the sea cliff through the seashore and coastal cliff to plateau. The sea cliff, seashore, and coastal cliff, which compose the coastal landscape, were dominated by the seashore spatulate aster (Aster spathulifolius Maxim.) community, dwarf sand sedge (Carex pumila Thunb.) community, and seashore spatulate aster (Aster spathulifolius Maxim.) community. On the plateau corresponding to the ridge of the coastal cliff, black pine (Pinus thunbergii Parl.) community, golden rain tree (Koelreuteria paniculata Laxmann) community, east Asian hackberry (Celtis sinensis Pers.) community, sawleaf zelkova (Zelkova serrata Makino) community, and Korean oak (Quercus dentata Thunb.) community were established in the mentioned order along distance from the sea. Stand ordination showed a vegetation sequence from the seashore through the cliff to the plateau, consistent in its overall pattern among sites. This was dominated by topography. There is evidence for the importance also of salinity, drought and of soil depth. Conclusion: The lack of scientific interest in cliffs to date is in striking contrast to the commonness of cliffs around the whole national territory and to the attraction cliffs have had for humans throughout history. Cliffs provide a unique habitat, rarely investigated from an ecological viewpoint. Cliffs may represent an invaluable type of ecosystem, consisting of some of the least disturbed habitats on earth and contributing more to the biodiversity of a region than their surface coverage would indicate. Although this coastal area where this study was carried out was designated as a conservation reserve, this area is in danger of severe disturbance due to excessive recreational use. We recommended a restoration plan to protect this area from such a disturbance.

Ecological Characteristics Analysis and Management Plan of Freshwater Lake Basin - A Case Study on Duryang Reservoir at Sacheon - (담수호소 유역 수변의 생태적 특성과 관리방안 연구 - 사천시 두량저수지를 사례로 -)

  • Lee, Soo-Dong;Kim, Sang-Bum
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.37 no.1
    • /
    • pp.50-64
    • /
    • 2009
  • The freshwater lakes located at the fringe of urban cities are a habitat for diverse organisms. However, they are facing severe danger of environment deterioration and water pollution caused by reckless development of the area. In this study, an ecological management plan was suggested to promote the biodiversity through appointing management area based on the research and analysis data of flora and fauna as well as maintain biodiversity and harmonize utilization of freshwater lakes such as Duryang Reservoir at Sacheon, Gyeongsangnam-do. Base on the data of ecological research and analysis, this study conducted research on biotope assessment, wild life habitat assessment and presence of protected species. As a result, the ecosystem conservation area including multi-layer structured natural forests, waterside and wetland that are home to various species and the edge area with high habitat diversity were recognized as highly preservable regions. Management areas were ecologically disturbed region, highly polluted commercial district and damaged waterside caused by fishing. Proactive management must be implemented through vegetation management such as vegetation transition and shrub planting as well as establishing pollutant management system. The deterioration of waterside and forest vegetation of freshwater lake has a direct influence on biodiversity and water quality. Therefore, the conservation area and development area should be totally separated from each other, and the development area must be restored and managed strictly.

A Study on the Environmental Assessment of Development Projects within Management Zones (관리지역 내 개발사업에 대한 환경성 평가방안 연구)

  • Sung, Hyun-Chan
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.13 no.3
    • /
    • pp.114-127
    • /
    • 2010
  • This study aimed at reviewing the case examples of environmental assessment of development projects within management zones, identifying problems and improvement opportunities and suggesting the direction of environmental assessment for management zones that are increasingly segmented Findings showed that first, the assessment of environment soundness in management zones must incorporate the national land environmental map and wide-area ecological axes established by the Ministry of Environment. Second, regarding development activities in management zones, rather than an issue of simply destroying natural environment in a development site itself during a development period, an issue of permanently isolating ecosystems from surrounding areas in a mid/long-term perspective and continually polluting water in mid-stream/upstream regions where sites are located must be considered. Third, in the case of development projects with vast areas, existing plant communities will be disturbed and the naturalness of vegetation will gradually decline due to foreign tree species introduced for landscape architecture. Therefore, creating buffer forests at forest boundaries and planting native tree species that are same as nearby tree species must be examined. Last but not least, when assessing the environmental soundness of management zones, it would be crucial to comprehensively review the environmental, social and locational features of management zones, including surrounding areas, and set the direction of environmental assessment accordingly.

Four Cases of Scrub Typhus Treated with Azithromycin in Children (소아에서 발생한 쯔쯔가무시 열에서 Azithromycin 치료 완치 4례)

  • Kim, Eun Jung;Lee, Chang Yoo;Oh, Yeon Gyun;Yun, Hyang Suk;Kim, Jong Duck
    • Clinical and Experimental Pediatrics
    • /
    • v.46 no.2
    • /
    • pp.188-191
    • /
    • 2003
  • Tsutsugamushi fever is a serious febrile disease outwardly similar to malaria and various arboviral infections. The endemic area is Asia-Pacific. This disease are generally associated with disturbed habitats favoring large populations of vector larval trombiculid mites. Therapy with tetracycline, chloramphenicol or ciprofloxacin is currently recommanded. Unfortunately these drugs is suboptimal for children and pregnant women. Recently, azithromycin has been proven to be effective in therapy of scrub typhus. There is no evidence that azithromycin causes adverse reaction to developing fetus or children. We report four cases of tsutsugamushi fever in children successfully treated with azithromycin. This is the first report describing clinical application of azithromycin to tsutsugamushi fever in Korean children.

An Acoustic Analysis of Speech in Patients with Nonfluent Aphasia (비 유창성 실어증 환자 말소리의 음향학적 분석)

  • Kim, Hyun-Gi;Kang, Eun-Young;Kim, Yun-Hee
    • Speech Sciences
    • /
    • v.9 no.3
    • /
    • pp.87-97
    • /
    • 2002
  • The purpose of this study is to analyze the speech duration in Korean-speaking aphasics. Five patients with nonfluent aphasia (2 with traumatic brain injury and 3 with strokes) and five normal adults participated in this experiment. The mean age in patients with nonfluent aphasia was $45.8\pm2.3$ years and $47.4\pm2.3$ years for the normal adults. The Computerized Speech Lab was used to evaluate the acoustic characteristics of the subjects. Voice onset time, vowel duration, total duration, hold and consonant duration were evaluated for the monosyllabic and the polysyllabic words. The patients with nonfluent aphasia did not show the voicing bar on hold area, however, it was seen in the normal persons in the intervocalic position. Explosion duration of glottalized stops in the intervocalic position was significantly prolonged in nonfluent aphasics in comparison with the normal persons. This suggestes that the laryngeal adjustment is disturbed in these patients. Consonant duration, vowel duration, and total duration of the polysyllabic words were significantly longer in the patients with nonfluent aphasia than those of the normal persons. These results demonstrate the disturbances in controlling articulatory muscles during sound production in patients with nonfluent aphasia. The objective and quantitative analysis based on the acoustic characteristics of nonfluent aphasics, will be very useful in therapeutic planning and on the the effects of speech therapy.

  • PDF