• Journal of Wetlands Research
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• v.21 no.4
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• pp.321-333
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• 2019

A primary aspect of low impact development (LID) design that affects performance efficiency, maintenance frequency, and lifespan of the facility is the type of filter media as well as the arrangement or media profile. Several LID guidelines providing media specifications are currently available and numerous studies have been published presenting the effectiveness of these systems. While some results are similar and consistent, some of them still varies and only a few focuses on the effect of filter media type and arrangement on system performance. This creates a certain level of uncertainty when it comes to filter media selection and design. In this review, a synthesis of filter media specifications from several LID design guidelines are presented and relevant results from different laboratory and field studies are highlighted. The LID systems are first classified as infiltration or non-infiltration structures, and vegetated or non-vegetated structures. Typical profiles of the media according to classification are shown including the different layers, materials, and depth. In addition, results from previous studies regarding the effect of filter media characteristics on hydraulic and hydrologic functions as well as pollutant removal are compared. Other considerations such as organic media leaching, clogging, media washing, and handling during construction were also briefly discussed. This review aims to provide a general guideline that can contribute to proper media selection and design for structural LIDs. In addition, it also identifies opportunities for future research.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.6
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• pp.639-647
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• 2009

In line with the rapid settlement of information society, the demand for geospatial information and its applications are dramatically increasing. The Project of National Geographic Information System(NGIS) is actively on going to meet up-to-dateness and accuracy of geospatial data. It is fact that the public interest in environmental issues is increasing than ever in accordance with the restoration of the four major rivers, core project of Green New Deal Policy, and the event of the Ramsar General Meeting. Because the Nakdong River Estuary is a place of great importance in both aspects of wetland and environment conservation, a variety of researches related to this area are progressing. Although artificial developments and natural phenomena are rapidly changing the topography and ecosystem of this area, the effort to build topographic DB for change monitoring is very slow. This study describes a Lidar surveying project over the restored wetland Eulsukdo, the southermost part of the Nakdong River, to establish precise topographic DB throughout producing 3D topographical maps and wetland classification maps. The results of this study will make a large contribution to the systematic maintenance and management for the restored Eulsukdo wetland.

• Journal of Life Science
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• v.22 no.12
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• pp.1600-1607
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• 2012

The matrix metalloproteinase (MMP) family plays essential roles in physiological processes such as embryonic development, angiogenesis, wound healing, and tissue homeostasis as a consequence of MMPr capacity for breaking down many types of extracellular matrix proteins. Imbalanced regulation of MMP expression can also lead to pathological conditions such as tumor progression. We recently reported that the Drosophila Mmp1 gene is highly expressed in the digestive tract and is required for the maintenance of intestinal homeostasis such as by restriction of uncontrolled intestinal stem cell proliferation. However, the regulatory mechanisms of MMP gene expression in the intestine remain unclear. In this study, we determined that the expression of Mmp1 is regulated by the homeodomain transcription factor Caudal. Experiments using the targeted expression of Caudal under the regulation of Gal4-UAS system indicated that endogenous Caudal is required for the Mmp1 gene expression in the adult Drosophila intestine and that exogenous Caudal induces Mmp1 expression. Transient transfection experiments indicated that Caudal can activate the promoter activity of Mmp1 and that several putative Caudal binding sites in the 5'-flanking region of the Mmp1 gene may be critical to the upregulation by Caudal. Our data suggest that Mmp1 is one of the target genes of Caudal in physiological normal condition and in tumorigenesis.

• Molecules and Cells
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• v.41 no.7
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• pp.653-664
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• 2018

The RNA-binding protein tristetraprolin (TTP) binds to adenosine-uridine AU-rich elements in the 3'-untranslated region of messenger RNAs and facilitates rapid degradation of the target mRNAs. Therefore, it regulates the expression of multiple cancer and immunity-associated transcripts. Furthermore, a lack of TTP in cancer cells influences cancer progression and predicts poor survival. Although the functions of TTP on cancer cells have previously been researched, the mechanism of TTP on the interaction between cancer cells with their micro-environment remains undiscovered. In this study, we admed to determine the role of cancer cell TTP during the interaction between tumor and immune cells, specifically regulatory T cells (Tregs). We evaluate the capability of TTP to modulate the antitumor immunity of GC and explored the underlying mechanism. The overexpression of TTP in GC cells dramatically increased peripheral blood mononuclear lymphocyte (PBML) -mediated cytotoxicity against GC cells. Increased cytotoxicity against TTP-overexpressed GC cells by PBMLs was determined by Treg development and infiltration. Surprisingly, we found the stabilization of programmed death-ligand 1 (PD-L1) mRNA was declining while TTP was elevated. The PD-L1 protein level was reduced in TTP-abundant GC cells. PD-L1 gas been found to play a pivotal role in Treg development and functional maintenance in immune system. Taken together, our results suggest the overexpression of TTP in GC cells not only affects cell survival and apoptosis but also increases PBMLs -mediated cytotoxicity against GC cells to decelerate tumor progression. Moreover, we identified PD-L1 as a critical TTP-regulated factor that contributes to inhibiting antitumor immunity.

• Journal of the Korean Geotechnical Society
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• v.28 no.9
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• pp.17-22
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• 2012

Wind blown sand is expected to disrupt the operation of the railway as the presented railway project in this paper consists of large earthworks in extreme topography of the mega dune fields. For successful railway construction in sand dune area, effective mitigation measure is the most important factor to protect the track from wind blown sand. The effective mitigation measure requires an integrated consideration of the earthworks geometry and the direct control measures such as fence system. Basically there's no perfect measure protecting railway track from wind blown sand, and it would be more economical and effective to develop robust, deliberate maintenance program for track and direct control measure on the basis of geo-morphological study. The purpose of this study is to identify the large scale geo-morphological terrains and specific sand dune morphology in the project area in UAE and estimate the direction and migration rate for sand dunes with the local variations in prevailing wind directions by undertaking literature review, and aerial photographs, satellite images, and ground studies.

• Korean Journal of Construction Engineering and Management
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• v.8 no.4
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• pp.73-80
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• 2007

As BTL(Build-Transfer-Lease) private investment business benchmarking PHI(Private Finance Initiative) of USA and Japan is introduces to Korea since 2005, as a part of supplying high leveled public service and early expanding required facilities for SOC, Value for Money on private investment business from treasury investment business at the beginning gets to be needed. Accordingly, this survey has been conducted in order to analyse BTL projects status, propriety of economic analysis method(VFM analysis, calculation of estimated business expenses, valuation of bidding price, etc.) by business advance phases from the viewpoint of person in charge, necessity of improvement and alternative plants. As the result of conducting cross tabulation analysis and correlation analysis by occupational group, BTL project advance phases and alternative plans for improvement, it is necessary ye prepare standardized service level against business expense and basis for calculating and evaluation operation expenses. Based on the necessity of quantitative analysis (LCC analysis) of VFM, standard for calculating management, maintenance and administration expenses is required. In addition, reliable economic valuation system considering domestic BTL environment should be setup, for business efficiency.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.2
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• pp.11-24
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• 2004

The purpose of this study is to present data on the human activities responding to the physical environment of ‘Ulsan’s Grand Parks by evaluating user behavior and activity, visiting motivations, and user satisfaction. This study was conducted using multi-methods such as interviews and questionnaires surveys. The main findings of this study can be summarized in six parts as follows: \circled1 Behavior patterns showed that the users visited the park left within 30 minutes and the frequency of visits was 1 or 2 times per week. They spent their time mostly on ‘walking’ and ‘picnicking’. The users visited regardless of the seasons or the day of the week. \circled2 The priorities for improvements were analyzed as follows: the users expressed their demands for ‘shadowing facilities’ like shelters and pergolas because they used these facilities frequently. Also, the users would like an ‘event program’, ‘sign system’ and ‘guide program’. \circled3 Analysis of the the user’s perception of the park showed that they perceive the park as ‘representative source of the landscape and open space in Ulsan and place for making contact with nature. \circled4 In examining the visiting motivations of the users of Ulsan Grand Park, it was revealed that people use the park for ‘time with family and friends’, ‘to escape from city life’, ‘to relieve fatigue. As a result of factor analysis, 4 factors were identified such as ‘physical motive(MF1)’, ‘exploratory motive(MF2)’, ‘social motive(MF3)’ and ‘emotional motive(MF4). \circled5 Park users’ evaluation for park facilities showed that people are satisfied with most of the facilities and especially, they have high level of satisfaction for ‘footpaths’, ‘squares’ and ‘picnicspace’. The evaluation of the park user’s of activity reveals that they are content with nearly all the variables. Especially, they have high level of satisfaction for the variables of ‘convenience for dynamic activities’, ‘making of a beautiful atmosphere, ‘accessibility from the outside’ and, ‘convenience in group activitie. Factor analysis of the park user’s of activity revealed 5 factors such as ‘convenience and interest factor (AF1)’, ‘park maintenance, management and use program(AF2)’, ‘visual beauty(AF3)’, ‘safety and accessibility(AF4)’ and ‘crowding(AF5)’. \circled6 Regression analysis was employed to get the predictor factors of overall satisfaction with a result of 60.0%($R^2$). The variance was explained as ‘quality of the picnic space’, ‘convenience and interest factor while using the park’, ‘park program for maintain and management in the park’, ‘visually beauty while using the park’, ‘safety and accessibility of the parks’, ‘quality of the pond’, ‘crowding’, ‘quality of the square’.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.5
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• pp.31-41
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• 2010

This research aims to present a methodological approach for repurposing small pockets of national/public lands, which can be constructed as parks, through an investigation of the present status of these areas of national/public lands that are scattered around Busan Megalopolis as well as the suitability of their construction. In order to attain this, this study looked at the present status of these small areas of national/public lands by utilizing a national land, city land list (lot number), land registration map and satellite image of Busan Megalopolis, and evaluating their suitability as parks through GIS analysis and classification. As a result, these small areas of lands with the potential to be turned into parks include 516 spots($375,934m^2$). Geographically, 39% of these areas are located on flat land and are the most scattered. 260 places met the requirements for optimal placement for conversion, while convenience included 305 places, and availability 267 places. The most optimal of the places meeting such standards include 61 spots. The characteristics of these areas of national/public lands include being below $500m^2$, with flatlands and open areas above a 5' grade occupy the highest ratio, accounting for 25.4% of the land studied. These results have offered a methodology for a GIS DB, which can visualize the data for a positive utilization be yond the simple level of the maintenance/preservation of national/public lands and provide basic data for the utilization and management of these types of areas in the future.

• The Journal of Engineering Geology
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• v.12 no.2
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• pp.215-234
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• 2002

Groundwater Dam is one of the reliable techniques to get huge amount of groundwater abstraction for municipal, agricultural, drinking, industrial water supply system. It can be a major technique to solve water shortage problems when it based on the sufficient watershed, proper topology, and adequate aquifer distribution and pollution control, Groundwater Dam had initiated its construction by RDC(former KARICO) in early eighties in Korea and 4 of it in total were added more until late eighty. However, this technique has shrunken its application due to gradually decreased yield rate after sever years of construction. After we studied several existing sites precisely, we concluded that the main reason of decreasing yield rate was come form engineering roughness on construction in early nineties. Theoretically, the technique itself seemed to be little detectives however, there were a little application in the fields in Korea. With the recent advance in engineering fields, those defects in construction would be no longer obstacle to construct underground wall and the technique could be a one of major ground water production technique in the future. It is essential to study following items thoroughly before select the appropriate site. The topography and the site of the underground wall, aquifer distribution, the specific technique for wall construction to block groundwater flow effectively and strict quality control during construction are critical. The surface and ground water monitoring data should be collected. Sustainability of the Groundwater Dam with huge groundwater abstraction in long term should be based on the long-term water balance analysis for each site. The water quality, environmental effect analysis and maintenance achedule should be also analyzed and planned in prior. It is suggested that the two consecutive underground wall in the coastal area to prevent seawater intrusion beneath a single wall.

• Ecology and Resilient Infrastructure
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• v.2 no.2
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• pp.167-176
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• 2015

The water quality of the Gulpo Stream flowing through Incheon, Bucheon, Seoul, and Kimpo is getting worse due to a slow flow rate and bank constructions by stream channelization as well as an inflow of pollutants from living-sewages and factory-sewages. Besides, a dry stream phenomenon caused by a lack of maintenance water upstream makes a self-purification system worse, and the water quality of the Gulpo Stream is currently at its lowest level. The accumulated sludge of the streambed is mostly formed by the deposition of particle pollutants due to the slow flow rate and an artificially straightened stream channel. This accumulated sludge adsorbs a great quantity of organic materials and heavy metals. Because of the internal contamination possibility by a re-gushing, even after the pollution source is removed, it can cause future water pollution. Without a total examination as previously recommended, it is considered difficult to accomplish practical efficiency. In conclusion, the management of periodic sediment management such as dredging would be necessary in the Gulpo Stream because sediment could be an internal pollution source of stream water under anaerobic conditions.