• Journal of Korean Society on Water Environment
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• v.22 no.3
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• pp.456-461
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• 2006

The facility of constructed wet land combined with filter media was examined in order to improve the water quality of a polluted stream, which has been performed as a part of national projects. Throughout 2 years of operation for a stream, it can provide the design and operating parameters for the purpose of future construction. The influent flow rate was about 50% against the design capacity. The removal efficiencies of BOD, $COD_{Mn}$, SS, T-N and T-P were 62.9%, 47.1%, 74.8%, 22.4% and 33.5%, respectively. In order to keep this facility stable, the removal of surface filter media and supplement should be periodically conducted. In addition, the proper selection of sites is recommended not to be flooded.

• Journal of Korean Society of Rural Planning
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• v.3 no.2
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• pp.50-61
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• 1997

As one of methodological approaches for objective and systematic evaluation for rural resources, a sequential system for significance determination of resources items was formulated using AHP (Analytic Hierarchy Process) as the base technique. By the system constructed in this study, the significance values were calculated for all items of standard goal system which had been presented in the first phase- paper of research works for rural resources evaluation. The results analysed and obtained in the study are summarized as follows; 1. In case that the number of resources items for evaluation are relatively large, stepwise matrix method is considered as the better one for pair-comparison works in view of evaluator's convenience and consistency. 2. The significance valuing results for most resources items showed a considerable difference between characteristic areas, especially in aspects of land and human resources, so being considered as wet reflecting the specific areal varieties, 3. On land resources, the items for industrial development and land use showed higher significance value, while natural environment resources the items for ecological varieties and on human resources the items for artificial facilities. However, lower-valued ones were the items for mineral stocks in land resources, for control and protection in natural environment resources and for lower-level culture heritage respectively.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.5
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• pp.380-390
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• 2009

This study was conducted as a part of investigating pre-reclamation shorelines from aerial photographs to estimate coastal land area at reclaimed lands (Anjeong industrial complex, Myeongji residental complex, and Noksan industrial complex), southeastern coast of Korea. To assess how the shorelines were suitable for the calculation of coastal lands, we constructed shoreline change data. Secondary ground control points were used to accomplish triangulation for old aerial photographs. Two kinds of shorelines were mapped; one was the shoreline based on approximately highest high water level (AHHWL) and the other was the high water line based on wet/dry signiture. These shorelines were consistent at artificial coast. Shoreline change data were built with a variety of levels of error due to detailed differences in the photograph scale, quality of image, type of ground control point and type of shoreline. Thus assessment of the pre-reclamation shorelines at the level of qualitative analysis for the trend of shoreline changes was satisfactory. Most of shoreline changes before reclamation in this study were associated with coastal development. Investigation of shoreline attributes in relation to aerial photographs allowed us to understand the shoreline changes.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.4
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• pp.55-63
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• 1997

Constructed wetland system which can be applied to the rural wastewater treatment system was examined by pilot plant in Kon-Kuk University. Hydraulic loading rate of wastewater was about 0.16m$^3$/m$^2$. day and theoretical detention time in the system was 1.38 days. The effluent of the septic tank for the school building was applied as inflow to the system. The influent concentration of DO was zero but effluent was up to 4.37mg/${\ell}$ which implies that oxygen was supplied enough from atmosphere by reaeration to support biological activity of the system. Average influent concentration of BOD was 104mg/${\ell}$ and effluent was 24mg/${\ell}$ with average removal rate of 76%. Average influent concentration of COD was 215mg/${\ell}$ and effluent was 63mg/${\ell}$ with average removal rate of 70 % . Average influent concentration of SS was 78mg/${\ell}$ and effluent was 10mg/${\ell}$ with average removal rate of 87%. Two components, BOD and SS, are regulated by law to keep maximum water quality standard of 80mg/${\ell}$ when daily outflow rate is less than 100$m^3$/day which is the case of most rural communities. Therefore, the results from the experiment showed that constructed wetland system can meet the water quality standard easily. Average influent concentration of total nitrogen was 165mg/lwhich is relatively higher than normal wastewater, and effluent was about 156mg/${\ell}$ with average removal rate of only 6%. Average influent concentration of total phosphorus was 41 mg/${\ell}$ and effluent was 6mg/${\ell}$ with average removal rate of 87%. Overall, constructed wetland system was thought to be effective to treat wastewater if nitrogen removal mechanism is improved. Considering low cost, less maintenance, and high treatability, this system can be a practical alternative for the wastewater treatment in rural area The experiment was performed during the summer and fall season, and treatment efficiency of the system is expected to decrease in low temperature. therefore, further study including temperature is required to evaluate feasibility of the system more in detail.

• Journal of Wetlands Research
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• v.19 no.1
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• pp.80-89
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• 2017

Researches about NPS(Non-point Pollution Source) reduction have been widely carried out in recent years. A pilot channel-type constructed wetland (wet swale) was constructed in Rongyin area to treat stormwater generated from a green house agro-land of 22.7 ha. From 2006 to 2008, monitoring was conducted to evaluate its performance on the removal effect for organic pollutants as well as nutrients. Totally, sampling trips of 17 rainfall events were made and they covered most types of storm events in Korea. The channel-type constructed wetland have average removal efficiencies of 78.3~92.0%, 56.4~66.1%, 28.2~45.5% and 50.6~66.4% for SS, COD, TN and TP, respectively. According to four methods for estimating the removal efficiency, the average efficiencies of TSS, COD, TN and TP are 86.0%, 60.1%, 30.1% and 53.5%, respectively. From 2006 to 2008, annual efficiency improved due to infiltration potential increase. It was found that most of the pollutants removed in this channel type of wetland was particulate solids bound pollutants, which is assumed fact that it lacks of physico-chemical treatment conditions which are commonly observed in the retention type of constructed wetlands.

• Korean Journal of Remote Sensing
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• v.26 no.3
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• pp.287-295
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• 2010

Water level of the Tonle Sap is largely influenced by the Mekong River. During the wet season, the lacustrine landform and vegetated areas are covered with water. Change detection in this area provides information required for human activities and sustainable development around the Tonle Sap. In order to detect the changes in the Tonle Sap floodplain, fifteen ALOS-PALSAR L-band data acquired from January 2007 to January 2009 and examined in this study. Since L-band is able to penetrate into vegetation cover, it enables us to study the changes according to water level of floodplain developed in the rainforest. Four types of images were constructed and studied include 1) ratio images, 2) correlation coefficient images, 3) texture feature ratio images and 4) multi-color composite images. Change images (in each 46 day interval) extracted from the ratio images, coherence images and texture feature ratio images were formed for detecting land cover change. Two RGB images are also obtained by compositing three images acquired in the early, in the middle and at the end of the rainy season in 2007 and 2008. Combination of the methods results that the change images present the relationship between vegetation and water level, leaf fall forest as well as cultivation and harvest crop.

• Land and Housing Review
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• v.5 no.4
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• pp.305-314
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• 2014

The technology-intensive unit modular method of factory production method is attracting attention by the limit of the labor-intensive and field centered wet construction method. In recent years, the unit modular method has been applied to the construction of schoolhouse and BOQ(bachelor offices' quarters), dormitories, etc. But the modular method still is not used in housing construction by the lack of verification of resident performance and construction cost. Therefore, this study analyzed the economics of modular house to vitalize the constructed residential building by modular method and to develop the modular method. According to the study results, the construction cost of the modular house was analysed more about 6.2% expensive than that of the existing housing. However, if the construction duration of modular house is shortened or the productivity of modular house is increased, the construction cost of modular house will be similar to the that of the existing house.

• Journal of Korean Society on Water Environment
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• v.23 no.6
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• pp.951-960
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• 2007

Window interface to Hydrological Simulation Program-FORTRAN (WinHSPF) developed by the United States Environmental Protection Agency (EPA) was applied to the upstream of Nam-Han river watershed to examine its applicability for loading estimates in watershed scale and to evaluate non-point source control scenarios using BMPRAC in WinHSPF. The WinHSPF model was calibrated and verified for water flow using Ministry of Construction and Transportation (MOCT, 3 stations, 2003~2005) and water qualities using Ministry of Environment (MOE, 5 station, 2000~2006). Water flow and water quality simulation results were also satisfactory over the total simulation period. But outliers were occurred in the time series data of TN and TP at some regions and periods. Therefore, it required more profit calibration process for more various parameters. As a result, all the study was performed within the expectation considering the complexity of the watershed, pollutant sources and land uses intermixed in the watershed. The estimated pollutant load for annual average about $BOD_5$, T-N and T-P respectively. Nonpoint source loading had a great portion of total pollutant loading, about 86.5~95.2%. In WinHSPF, BMPRAC was applied to evaluate non-point source control scenarios (constructed wetland, wet detention ponds and infiltration basins). All the scenarios showed efficiency of non-point source removal. Overall, the HSPF model is adequate for simulating watersheds characteristics, and its application is recommended for watershed management and evaluation of best management practices.

• Land and Housing Review
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• v.12 no.4
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• pp.103-117
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• 2021

With the current rapid changes in population and technology, the long-lastig housing certification system is a means of prolonging the physical and functional lifespan of a building. The certification requires differentiation between the structure and infill elements to allow for variability and ease of repairs. This works well with prefabricated houses so this study investigated the possibility of applying the long-lastig housing certification requirements to apartment construction using off-site construction (OSC) methods focused on the installation of bathrooms (plumbing and toilet) that differ from the traditional wet method. This study examined three different sized floor plans at 22 m², 46 m², and a combined one resulting in 69 m². The larger 69 m² plan utilized a removeable non-load bearing wall to increase flexibility in the layout of the floorplan. The apartments are constructed of steel reinforced concrete composite columns on a 9 m × 10.5 m grid with integrated slabs. The exterior and interior infill walls are all non-load bearing with some containing plumbing. This separation of the structure and infill walls can help meet some of the criteria in the long-lastig housing certification, particularly with the ease of repairs. Technologies that facilitate the replacement of infill elements that contain plumbing and other building services can benefit the nation by reducing carbon emissions and therefore tax incentives should be introduced to increase the adoption of the proposed construction methods.