• Animal cells and systems
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• 제10권1호
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• pp.27-40
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• 2006

Tree of heaven (Ailanthus altissima Swingle) as an invasive alien plant, appeared usually in the disturbed locations such as road-side, incised slope, and trampling path-side. They appeared abundantly in the trampling pathside but they did not appear or were rare in the interior of forest. Density and importance value of tree of heaven were proportionate to the relative light intensity measured according to distance from the trampling path toward forest interior and closely related to the breadth of trampling path as well. They were associated with annual, other exotic species or ruderal plants well. Distributional pattern of mature trees of them in the study area and its surrounding environments implied that they were introduced intentionally. Size class distribution of them showed that they are in expansion and artificial interferences such as, installing physical training space and developing hiking course functioned as trigger factors in their invasion and expansion. The results support the facts known generally in relation to invasion and expansion of the invasive alien plants. In this viewpoint, we suggest a management plan that applies ecological restoration principles to address ecosystems infected with tree of heaven by restoring the integral feature of the degraded nature and conserving the remained nature more thoroughly.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2002년도 추계종합학술대회
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• pp.624-627
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• 2002

본 논문은 TCP/IP 기반 지역 망 내에서 개인용 컴퓨터의 사용에 있어 인터넷 프로토콜의 주소 충돌 해결 방법에 대하여 연구하였다. 현재 컴퓨터의 수는 계속해서 늘고 있지만 사용자는 IP 주소에 대한 지식이 없음으로 인해 고의나 실수로 자신의 것이 아닌 다른 사람의 IP 주소를 사용할 수 있고, 이로 인해 원래 사용자가 네트웍을 사용할 수 없게 된다. 본 논문은 사전에 지역 망 내의 관리 대상 컴퓨터들의 주소정보를 수집하여 현재 사용하는 주소 정보가 저장된 정보와 같은 지를 Web Browser를 통하여 검사하는 방법으로 IP 주소 충돌 검출 시스템설계를 제시하였다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2002년도 추계종합학술대회
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• pp.916-919
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• 2002

본 논문은 TCP/IP 기반 지역 망 내에서 개인용 컴퓨터의 사용에 있어 인터넷 프로토콜의 주소 충돌 해결 방법에 대하여 연구하였다. 현재 컴퓨터의 수는 계속해서 늘고 있지만 사용자는 IP 주소에 대한 지식이 없음으로 인해 고의나 실수로 자신의 것이 아닌 다른 사람의 IP 주소를 사용할 수 있고, 이로 인해 원래 사용자가 네트웍을 사용할 수 없게 된다. 본 논문은 사전에 지역 망 내의 관리 대상 컴퓨터들의 주소정보를 수집하여 현재 사용하는 주소 정보가 저장된 정보와 같은 지를 Web Browser를 통하여 검사하는 방법으로 IP 주소 충돌 검출 시스템설계를 제시하였다.

• 한국해안해양공학회지
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• 제15권2호
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• pp.127-137
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• 2003

연안역 개발로 인해 갯벌의 면적이 급감하고 있는 현실에서 대체 갯벌의 조성을 위해 연구가 진행되고 있다. 본 연구는 인공갯벌 조성을 위한 연구사업의 일환으로, 자연적으로 형성된 갯벌지반과 인위적으로 조성된 갯벌지반의 지반공학적인 특성을 비교$.$고찰하고 그 결과를 토대로 인공갯벌 지반의 안정성을 평가하기 위하여 교란 및 불교란시료를 이용한 각종 실내실험을 실시하였다. 실내실험에서 측정된 전단강도와 조류와 파랑으로 인해 유발되는 전단응력을 비교하여 갯벌에 퇴적된 토사의 안정성에 대해 검토하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.111-118
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• 2002

Recent study of soft clay of Nakdong-River basin has been taken correlation between soil properties by regression analysis without distribution whether the sample is disturbed or not, or treated as a whole area without proposing local correlation equation to Jang-U or Dae-Joe which has a specific locality. Accordingly, Those tendency cause the reliability of correlation between compression index and void ratio low and then design underestimate and uncertain eventually. In this study, Distributing the soft clay of Nakdong-River basin with failure strain of 6%, the suggestion by Skempton(1957), TakeNaka(1966)-the more sample is undisturbed, the more the ratio of E$\_$50/ and ｑ$\_$u/, ${\alpha}$ = E$\_$50//(q$\_$u//2) = 1/$\varepsilon$$\_$50/ is high-is satisfied with the value of which ${\alpha}$ is 50 and It could be taken enough data in the condition of domestic. Besides other indices also make the distribution suitable. In conclusion, This study is supposed to propose the locally subdivided regression equation between compression index and void ratio considering the sample disturbance.

• 한국환경복원기술학회지
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• 제12권3호
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• pp.83-97
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• 2009

The objects of study is to propose criteria for physical river disturbance assessment and as case study to show the application results for river improvement. For this purpose, the river disturbance assessment method for past disturbance process and the present-day potential natural state of stream is proposed. To assess the disturbance of the Youngcheon River caused by river improvement, One ares of Nam River was selected for the reference reach and two areas of Youngcheon River were selected for the comparison reach. And these reaches were surveyed and analyzed according to applying criteria of the river disturbances assessment. The assessment indices were physical factors as like epifaunal (bottom), embededness, velocity/depth regime, sediment deposition, channel flow status, channel alteration, frequency of riffles, bank stability, vegetative protection and riparian zone etc. The results showed that physical river environment in Youngcheon River area was disturbed by artificial revetment and bed excavation, consequently this disturbance give rise to impact of ecosystem in river. Hereafter, the criteria for river disturbance assessment are needed to consider various river characters as bed materials and bed slop etc.

• 한국전기전자재료학회논문지
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• 제23권7호
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• pp.560-565
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• 2010

This paper presents the design factor of an overhead transmission tower structure in order to reduce the tower weight. The behaviour of transmission tower structures are affected by the horizontal angle of the tower structure, the equivalent wind pressure group, the slope of the main post of the tower, the separation of the internode and the use of high-strength materials in their construction. Tower weight can be reduced by approximately 30% reduce weight by means of optimal design based on a consideration of all the above factors. In addition, the design of the foundation of the tower with the shear key installation to increase horizontal support together with a modified angle of inclination to the ground can reduce by about 37% the amount of concrete used during construction. The area of ground disturbed by the construction of the tower foundation can thus be reduced by approximately 33%. Therefore it is possible to build an environmently-friendly T/L tower with the mechanical properties of existing towers.

• Journal of Microbiology
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• 제41권4호
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• pp.271-276
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• 2003

The inoculation of some microorganisms into a microcosm containing soil from a barren lakeside area at Lake Paro in Kangwon-do enhanced plant growth significantly. The direct and viable counts of soil bacteria and soil microbial activities measured by electron transport system assay and fluorescein diacetate hydrolysis assay were higher in inoculated soil. The plant growth promoting effect of this inoculation may be caused by phytohormone production and the solubilization of insoluble phosphates by the inoculated bacteria. Three inoculated strains of Pseudomonas fluorescens produced several plant growth promoting phytohormones, including indole-3-acetic acid (auxin), which was confirmed by thin layer chromatography and GC/MS. P. fluorescens strain B16 and M45 produced 502.4 and 206.1 mg/l of soluble phosphate from Ca3(PO4)2 and hydroxyapatite, respectively. Bacillus megaterium showed similar solubilization rates of insoluble phosphates to those of Pseudomonas spp. We believe that this plant growth promoting capability may be used for the rapid revegetation of barren or disturbed land.

• 한국환경과학회지
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• 제24권11호
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• pp.1405-1415
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• 2015

This study is conducted to determine the damage, distinguish the types and identify the restoration by that type for 13 Korea national parks out of 21. There are 21 Korea national parks are in Korea covering 6.67% of the country or $6,656km^2$ ($3,902km^2$ on land and $2,754km^2$ in the sea) currently since the area around Jirisan ($440km^2$) was designated as the first Korea national parks in 1967. With the cancellation of entrance admission on Korea national parks since 2007, annual visitors to the Korea national parks have grown from 37 millions in 2008 to 46 millions by 2013 and continue to grow due to numerous leisure activities, alpine activities and social changes. As such, Korea national parks are natural resource with high value to be conserved and are attracting significant attention as recreational spaces for people at the same time. On the other hand, there have been issues of soil erosions or disturbed vegetation due to increased number of visitor to the national parks. Korea national parks area damage to its type and damage characteristics to analyse the 13 Korea national parks out of 21 on July 2012 March, Korea national parks over the subjects of the National Park from damaged area status Survey analysis by the Korea National Park Service. As a result, 203 million units in the 16 Korea national parks damaged land of the reform package during ecological trail (including non-regular hiking trails) 153 (77.66%), damaged valleys 20(9.14%) independent damaged area, 13 disconnected ecological axis(7.61%), closed trail(2.03%) (3.55%), and line type damage(like a non-regular hiking trails) appears to be a high ratio. Korea national parks damaged land of the results identified, by contrast ratio and the annual number of visitors Bukhansan national park(49.26%), Gyeongju national park(23.65%) damaged land rates, such as Seorasan national park(4.93%), Songnisan national park (4.43 %), Gyeryongsan national park(3.45%), and the annual number of visitors be similar result. The National Park Service has been reporting on damages and restorations but damages and their types have not been established yet. Damages have been generally studied and categorized on hiking trails due caused by heavy traffic on them but the reports were limited on hiking trails only. Since damage to the Korea national parks are not limited on the hiking trails, it is necessary to determine damages in various aspects. Thus, in this study, damage types, spatial characteristics, causes and restorations are analyzed based on the survey results of damages to national parks in order to provide a basis for the efficient management and operation of the Korea national parks.

• 자원환경지질
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• 제24권4호
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• pp.421-434
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• 1991

경상분지내에서 가장 뚜렷한 선구조로 나타나는 양산 단층이 지나는 곳으로 생각되는 네 지역을 선정하여 육상자력탐사를 실시하였다. 정성적 분석을 위한 자료처리과정으로는 표준자기장 (IGRF) 보정, 상향 연속과 자극화 변환을 수행하였고, 정량적 해석을 위해서는 수평 2층 지하 지질구조에 있어서 하부층까지의 심도를 모델변수로 하는 비선형 자동 역산법을 적용하였다. 육상자력 이상도의 상향 연속 결과와 동일 지역에서 수행된 항공 자력 탐사자료를 비교한 바에 의하면 두 자료의 유사도가 비교적 높게 나타났다. 네 곳의 탐사지역내에서 양산 단층의 주향은 북동$6^{\circ}-15^{\circ}$의 경향이 우세하게 나타났으며, 단층의 경사는 지역적인 암상의 변화에도 불구하고 수직내지 약간 동쪽 방향의 경사를 갖는 것으로 나타났다. 탐사 지역중 가장 북쪽에 위치하는 안강부근의 제 1 탐사지역에서는 단층구조에 의한 자력효과가 화성암의 관입에 의한 효과와 함께 나타난 복잡한 양상을 띠며, 언양부근의 제 2 탐사 지역에서는 단층면을 따라 약 200 - 300 미터의 폭을 갖는 화산성, 혹은 화성 기원의 관입이 일어난 것으로 보인다. 용연 부근의 제 3 지역에서는 다른 지역과는 달리 단층운동에 의한 것으로 생각되는 파쇄대가 약 600 - 700 미터 정도의 폭으로 비교적 뚜렷하게 나타났다. 가장 남쪽에 위치하는 양산부근의 제 4 지역에서는 안산암 시료가 매우 큰 대자율 값을 보이며, 본 연구 결과 이 지역의 단층선은 기존 연구에서 제시된 단층선보다 약 500 미터 정도 동쪽으로 치우쳐 나타난다.