• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.4 no.2
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• pp.4-10
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• 1993

In mobile radio communication, propagation paths are time or spacial varying because of the motion of mobile unit. The propagation path loss not only involves frequency and distance but also the antenna height at both the base station and the mobile unit, terrain configuration, and the man made en- vironment. Thhese additional factors make the prediction of propagation path loss of mobile radio signals more difficult. In this paper, it is measured field strenght of mobile radio signals in Daejeon and Seoul area, also calculated local median, 500m sample mean, and stadard deviation. As the result of analysis, it can be seen that propagation path loss of measured data is similiar to predicted field strength, especially local median is dependent upon base antenna height, terrain configuration and the man-made environment. The standard deviation has been noted to lie between 2 and 10 dBuV.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2004.03a
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• pp.475-479
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• 2004

위성에서 감지되는 조간대 원격 반사도는 함수율, 퇴적상, 지형과 생물체 등의 영향에 의해 결정된다. 따라서 다른 환경요인을 제거하지 않고 위성자료 값을 분류하여 퇴적상과 비교한다면 좋은 결과를 얻을 수 없다. 하지만 퇴적상과 다른 환경요인은 관계가 복잡하고 미묘하게 얽혀있기 때문에 위성 자료 값에서 정량적으로 분리하거나 고려하는 것은 매우 어렵다. 특히 mud flat의 조류로나 세곡 부분은 배수구배의 발달로 인해 표층이 빠르게 마르게 되어 매우 높은 광학 반사도를 보이고 이는 sand가 우세한 지역의 높은 광학반사도와의 구별을 어렵게 만든다. 따라서 본 연구에서는 위성자료의 원격반사도 값만으로 조간대의 표층 퇴적상을 분류할 경우 에러가 발생할 수 있는 이러한 문제를 해결하기 위하여 조간대 texture와 표층 퇴적상과의 관계를 파악하고자 한다. 6.6 m 해상도를 갖는 EOC 자료를 이용하여 조류로의 형태와 밀도를 알아내고, 현장에서 샘플 된 입도 자료를 분석하여 비교함으로서 상관관계를 알아보고자 한다. mud flat의 경우, 대부분 복잡한 texture 구조를 갖고 밀도가 매우 높게 나타났으며 mixed flat 지역에서는 직선 구조를 갖는 큰 조류로가 발달하며 일부지역에서는 표면수가 잔존함에 의해 조간대에서 가장 어둡게 나타났다. 반면 sand shoal 이나 chenier 등과 같이 sand의 함량이 매우 높은 곳에서는 지형이 높아 함수율이 매우 낮아 높은 광학 반사도를 보임을 알 수 있었다.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.3
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• pp.21-27
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• 2010

When the capacity of underground caverns' structures is measured, a general surveying is difficult to decide an accurate section of irregular shape and a photographic surveying has problems on picture acquisition due to underground dusts, noise and lighting conditions, etc. The laser scanner system is being much used for 3-dimensional modeling such as topography, planimetric features and structures, etc. without a target by measuring arriving time of a laser pulse reflected after scanning the laser pulse and calculating space coordinates of the reflection position. Accordingly, the present research carried out section and earthwork volume measurement of a tunnel by using a laser scanner in underground anchorage excavation work that a bridge construction is being executed.

• Journal of Korean Tunnelling and Underground Space Association
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• v.3 no.4
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• pp.25-34
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• 2001

As the topography of Korea consists of mountains at about seventy percent, there is necessarily an increasing demand for tunnel construction according to the expansion of the existing highway and construction of new highway. The concrete lining of tunnel portals has been designed with reinforced concrete to resist the cracking due to the difference in temperature in the inside and outside of tunnel. In the paper, the application of steel fiber reinforcement concrete was analyzed as the lining concrete at tunnel portals and through structure analysis and field model test the suitability of the steel fiber reinforcement concrete was assessed as the lining member of tunnel portal.

• Korean Journal of Remote Sensing
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• v.34 no.3
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• pp.439-450
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• 2018

The lineament is a linear or curved terrain element to discriminate adjacent geological structures in each other. It has been widely used for analysis of geology, mineral exploration, natural disasters, and earthquake, etc. In the past, the lineament has been extracted using cartographic map or field survey. However, it is possible to extract more efficiently the lineament for a very wide area thanks to development of remote sensing technique. Remotely sensed observation by aircraft, satellite, or digital elevation model (DEM) has been used for visual recognition for manual lineament extraction. Automatic approaches using computer science have been proposed to extract lineament more objectively. In this study, we evaluate the characteristics of lineament which is automatically extracted with respect to difference of spatial resolution of DEM. We utilized two types of DEM: one is Shuttle Radar Topography Mission (SRTM) with spatial resolution of about 90 m (3 arc sec), and the other is the latest world DEM of TerraSAR-X add-on for Global DEM with 12 m spatial resolution. In addition, a global DEM was resampled to produce a DEM with a spatial resolution of 30 m (1 arc sec). The shaded relief map was constructed considering various sun elevation and solar azimuth angle. In order to extract lineament automatically, we used the LINE module in PCI Geomatica software. We found that predominant direction of the extracted lineament is about $N15-25^{\circ}E$ (NNE), regardless of spatial resolution of DEM. However, more fine and detailed lineament were extracted using higher spatial resolution of DEM. The result shows that the lineament density is proportional to the spatial resolution of DEM. Thus, the DEM with appropriate spatial resolution should be selected according to the purpose of the study.

• Korean Journal of Environment and Ecology
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• v.16 no.3
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• pp.321-337
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• 2002

This study was carried out to draw up the planting plan of bridge type ecological corridor for animals migration at Hakgogae(ridge) destroyed by road construction in Yongin, Gyeonggi-do, South Korea. It was conducted with two steps, survey and planting master plan. We surveyed the structure of topography, plant community, and animal habitat. We also selected the target species migrate ecological corridor and suggested a concept of each planting area, the planting species, and the planting density based on the analyzed data and finally drew up the planting plan. The structure of topography was a steep slope due to the mountain ridge destruction so the bridge type ecological corridor was could be applied in this study and we supposed that the animals migrate along the both edge of corridor. As the results of analyzed plant community structure in two sides, the dominant woody species, Quercus serrata and Q. variabilis were distributed on the bottom and the belly of a mountain, while Pinus densiflora community was distributed on the mountain ridge as edaphic climax. The similarity between Q. serrata -Q. mongolica -Q. variabilis community on the West of survey site and Q. serrata -Q. mongolica community on the East of survey site was high in 71.0 percentages. As the results of surveying birds and some mammalia, seven species and fifty-seven individuals of birds were founded in survey area, and two species and two individuals of rodents were founded. We selected birds and some mammals for the migration species that supposed to migrate ecological corridor in drawing up the planting plan. And then we divided the planting areas into bird corridor and habitat, and mammals corridor, also suggested the planting areas in detail as follows: community planting area of shrub at slope adjacent to the bridge exit as a buffer zone, screen planting area, community planting area of herb at steep slope connected with mountain areas, inducement planting area of the animals, community planting area for bird migration, community planting area for mammals migration, and community planting area for bird habitat. We selected the planting woody species which were the constancy ratio based on the analyzed data of plant community around mountain areas was high, and suggested the planting master plan each space.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.908-912
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• 2006

Geology and terrain of Imha basin has a very weak characteristics to soil erosion, so much soil particles flow into Imha reservoir and bring about high density turbid water when it rains a lot. Especially, since the agricultural area of Imha basin is mainly located in river boundary, Imha reservoir has suffered from turbid water by soil erosion. Therefore, it is important to estimate the influence of soil erosion to establish efficient management of water-pollutant buffering zone for the reduction of turbid water. By applying GIS-based RUSLE model, this study can acquire 12.23% that is the ratio of soil erosion in water-pollutant buffering zone and is higher than area-ratio (9.95%) of water-pollutant buffering zone. This is why the area-ratio of agricultural district (27.24%) in water-pollutant buffering zone is higher than the area-ratio of agricultural district (14.96%) in Imha basin. Also as the result of soil erosion in sub-basin, Daegok basin shows highest soil erosion in water-pollutant buffering zone, second is Banbyeon_10 basin and last is Seosi basin.

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.4 s.34
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• pp.39-46
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• 2005

This paper use virtual running after possible traffic capacity application for optimal route location. General road is designed the design after we examine an alternate adequacy investigation and an execution design sufficiently. Various road user's requirement must be reflected from the beginning. But it is difficult to contain the various suitable design criteria because we consider the existing 2-dimension element. First of all, this study chose optimal route, used traffic assignment and 3D simulation. Then selected optimal route through the consistent road construction by analyzing road driving simulation of 3-dimension data and the urban landscape. possible traffic capacity and virtual running will be able to do the urban landscape analysis harmonizing with the environment; equally, it could be objectively solve the problem of a civil appeal.

• Journal of the Economic Geographical Society of Korea
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• v.22 no.2
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• pp.111-122
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• 2019

This study attempts to analyze the critical issues of globalization and present an alternative framework that places ICT in the function of development in comparative perspective. To adjudicate the controversies concerning the effect of developmental factors, it examines the determinants of global trend that leads to the comprehensive mechanism of ICT and cultural residues. The advent of the global community in cyber space requires a new balancing point by the mode of communication and culture among all societies and operation with decentralized authority. This interdependence, by providing diverse network structures and participating in cyberspace, includes the power shift from the dynamics of international relations with voluntary collaboration and brings some important implications for a global empathetic society.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.5-5
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• 2017

최근의 하천복원사업은 인위적으로 축소 또는 소실된 하천공간을 지형학적으로 되돌리기 위한 방향과 강이 가진 자연의 역동성의 복원에 주안점을 두고 있다. 최근 국내에서도 하천공간 확보라는 측면에서 구하천 구역을 복원하려는 시도가 이뤄지고 있고 대표적으로 청미천, 함평천, 황구지천 등에서 기존의 제방을 후퇴시키고 과거의 하천공간을 하천으로 되돌려 주었다. 그러나 이러한 시도는 구하도 또는 폐천부지 복원사업의 일환으로 시행되었으며, 복원된 공간규모가 크지 않아 사업의 효과를 크게 장담할 수 없는 현실적인 한계가 있다. 따라서 홍수에 안전하며 자연과 인간이 공존하는 터전으로의 공간복원, 그에 따른 하천생태계의 보전과 복원, 레저와 레크레이션이 가능한 친수공간 조성 등 하천기능의 강화와 융합을 종합적으로 고려한 다차원 하천공간 복원계획과 설계의 절차가 필요하다. 이를 위해서는 먼저 유역기반의 문제점과 그 원인에 대한 인식이 선행되어야 하고 그 해법으로 하천공간 확대의 필요성이 도출되어야 한다. 이후, 하천공간 복원 및 활용과 관련된 기본방향이 설정되며 세부 복원목표가 설정되어야 한다. 복원목적과 목표가 세워진 후, 복원대상지를 선정하고 공간 활용방안이 제시되면, 목표달성 여부 판단을 위한 효과분석이 필요하다. 만약, 기대효과를 달성할 수 없을 것으로 예상된다면 복원목표 재설정 및 복원대상지의 재선정이 필요할 것이다. 이와같이 하천공간 복원사업을 시행함에 있어 간결하고 단계적으로 접근하기 위해 본 연구에서는 다차원 하천공간 복원프레임워크를 개발하여 제시하였다. 제안된 하천공간 복원프레임워크를 통해 하천공간복원으로 인해 영향을 미칠 수 있고 또한 영향을 받을 수 있는 물리, 생물, 사회, 경제 등의 다양한 분야의 구조를 통합한 하나의 방법을 제시함으로서 임시방편 수준의 파괴된 하천복원사업에 변화를 주고 프레임워크를 통해 하천공간복원에 대한 응집력 있는 접근법을 적용하도록 촉진하여 복원사업에 참여하는 사람들 간에 공통의 유대감을 형성하는데 도움이 되고자 한다.