• The Journal of the Korea Contents Association
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• v.10 no.11
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• pp.452-460
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• 2010

This study carried out stability evaluation for design flood stage of vegetation models with river sites using 1D HEC-RAS and 2D RMA-2 numerical models. The vegetation models established in this study were divided into which channel reaches consist of urban, rural and mountain rivers with the social and cultural significance of the sites. Examination results from the numerical models showed a similar aspect with the design flood stage of these rivers before vegetation modeling. Also, no embankment overflow was shown from the urban river with additional vegetation density of 25%, although there were approximately 0.20m rising in the flood stage. In case of ural and mountain rivers, vegetation models showed scarce rising in flood stage.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.6
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• pp.61-72
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• 2014

We implemented ecological linkage assessment, through the connection components of the urban forests, rivers and parks, for the ecological connection of the urban parks which are standing out as the core of the urban green networks, so as to suggest basic data to compare, evaluate and improve urban green networks, as a basic study for the evaluation of the ecological connectabilities between the cities. For the ecological linkage assessment, we analyzed to see if the urban parks of Goyang, Ansan and Yongin, which are the subject cities, are actually ecologically connected with forests and rivers, using distance and roads, which are physical connection elements, in consideration of the mobility of the wild animals, and greening ratios and impervious pavement ratios, which are ecological connectabilities in consideration of the ecological values. The overall result of the ecological linkage assessment the physical connection elements and the ecological connection elements shows that the ecological green network ratio through direct connection states is 36.62% in Goyang, 42.55% in Ansan and 64.00% in Yongin, respectively, giving the ecological connectability ratio of less than half, with the average urban ecological green network ration of 47.72%. The comparison result of the ecological connectabilities between the object cities employing the connection elements indicates that when you set up green networks, you should consider together the physical connection elements, such as the roads, which will lower the ecological connectabilities - rather than do it simply based on areas and distances - while the ecological connection elements with the forests and the streams should be reinforced, so that the ecological connectabilities of the urban parks may be enhanced.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.746-751
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• 2006

The geumjunggu of the onchunchun which is the upper stream have been maintained as a too much picture to become a concrete lining about existing low flow channel and the reservoir water protecting banks for the reason of the flow of an upper stream steep slope and back of the shortage of the channel area in a suitableness interval. This research made a rating-curve to decide since to ensure against risks to the flood control through the undo of the rivers. And we found the speed of current of a nature undo interval and existing concrete interval and water level change out. A result from this natural disposition we must apply as a data for the research about the plan to be established in the rivers maintenance basis plan of onchunchun.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.12-17
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• 2006

Natural rivers have water purification functions called Gravel Contact Oxidation Process, which decontaminate river water by biological absorption, oxidation and degradation on riverbed gravels. This function has been developed and applied to many small/medium-sized urban rivers in Japan as one of the direct river water purification methods. However the method hasn't been verified in the tropics, which have different climate conditions and river characteristics. A preliminary experiment carried out at a polluted urban tributary in the outskirts of Kuala Lumpur, Malaysia where an increasing attention has been paid to river environment, showed a good applicability to the tropical conditions as a technically practical water purification measure with some maintenance cares for sludge management.

• Journal of Korean Society on Water Environment
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• v.23 no.5
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• pp.628-635
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• 2007

As the hydrologic cycle is transformed by the expansion of impermeable area as a result of the urbanization, the function of an ecosystem is deteriorated by the transformed hydrologic cycle. In this study, a SWMM code was modified to have a groundwater pumping option about rivers-aquifer interaction to be possible. The modified SWMM was applied to continuous simulations of urban runoff from Hakuicheon watershed and it was used to analyse the effect of a groundwater pumping. The modified SWMM overcame the limitation of the ground subroutine that it only simulate groundwater inflow from ground to rivers. The result of continuous simulation of groundwater pumping is that surface runoff, groundwater runoff and groundwater level are well simulated, and Modified SWMM expressed groundwater runoff by negative number (-) when groundwater level is less than river stage.

• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.521-532
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• 2018

In recent decades, the dry stream phenomena of small and medium sized rivers have been attracting much attention as an important social problem. To prevent dry stream phenomena, it is necessary to build an infrastructure that manages rivers. To accurately determine the progress of dry stream phenomena, it is necessary to continuously measure the discharge and other hydrological factors for small and medium sized rivers. However, until now, the flow data for small and medium rivers in Korea has been insufficient. To overcome the lack of supporting data for supporting rational decision-making in policy and project implementation, a short- and long-term hydrological model was developed that takes into consideration hydrological changes such as the increase of the impervious area due to urban development and groundwater pumping, the construction of a large-scale sewage treatment plant, the maintenance of stream-oriented rivers, etc. In the developed model, the distributed grid is represented by three layers: Surface flow, interflow, and groundwater flow. The surface flow and intermediate flow flowed along the flow direction, and the groundwater flow was calculated by a two-dimensional groundwater analysis model such that the outflow occurred in all directions without a specific flow direction. The effects of land use and cover on evapotranspiration and infiltration and the effects of multiple landscapes can be simulated in the developed model.

• KIEAE Journal
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• v.10 no.6
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• pp.47-54
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• 2010

The significant aim of this research is to suggest the applicable data for the future urban ecological restoration of rivers' activity and the direction of the future eco-experience program found by analyzing the state and progress of the restoration of the river ecological experience program. For this purpose, we researched the eco-experience program's outline and details of its operation and method from six rivers among all of the rivers going through restoration. We also carried out telephone interviews and in-depth interviews with the office staff that takes care about each river at the district office to investigate the specific details not revealed by our analysis, the number of operations, and the number of participants. We compared the number of operations to the number of participants and the frequency of participation of each river in a year. As a result, they have revealed that the participants of the eco-experience program ranged in variety including local students, families, and local citizens as a whole. Also the intimate observation and experience with nature gave the participants a better understanding of the ecosystem. In addition, it is revealed that the cheonggye river goes through its own standard of strict inspections and management daily. It is quite easy to notice that the cheonggye river shows a higher level of participation and operating activity than other rivers.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09a
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• pp.571-571
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• 2005

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.2
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• pp.59-67
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• 2015

When planning for streams, adequate and definite flood control should be in the primary consideration of the planner; likewise, flood control is the basic prerequisite for the recent river restoration taking place nationwide. Planning 'safe' streams and rivers that are predictable and controllable begins from accurate survey data. In this research, we will create streams in 3D terrain models and apply them through hydraulic analysis and restoration using smart geospatial information. This process allows the extraction of more accurate data regarding streams and rivers, which makes possible precise hydraulic analysis that is superior in details to the conventional methods. The study also proposes optimal vertical section interval for efficient data processing on hydraulic analysis, applicable when LiDAR data is utilized on hydraulic analysis of urban streams. The study proposes 3D design plan and various applications for spatially planning and restoring rivers and streams.

• Journal of the Korean GEO-environmental Society
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• v.15 no.6
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• pp.31-39
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• 2014

The objective of this study is to suggest the proper sediment transport equation and short and long-term bed change for planning and implementing the river management in Korea. To analyze total sediment discharge and short and long-term bed change, existing sediment transport equations, HEC-RAS 4.1 and CCHE2D numerical models were applied in urban and mountainous rivers. The results of this study are as followings; Firstly, the modified Einstein equation showed the most appropriate result for the estimation of total sediment discharge in the local rivers. Secondly, The stage-discharge relation curve and the discharge-total sediment discharge relation curve were suggested to examine the characteristics of river bed change. Finally, it is founded that river bed change of mountainous river has occurred greater than that of the urban river, and the river bed of urban river now tends to be stabilized on the whole.