• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.5
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• pp.50-59
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• 2006

This study was initiated to investigate soil chemical properties under different soil systems. Data such as soil acidity(pH), electrical conductivity(EC), organic matter content(OMC), and cation exchange capacity(CEC) were analyzed with samples from multi-layer, USGA, and mono-layer systems. N, P, K and micronutrients were also measured. Multi-layer system was built up to 60-cm depth with rootzone layer, intermediate layer and two drainage layers. USGA system 45 centimeters deep was constructed with rootzone layer, intermediate layer and drainage layer. Mono-layer system, however, was made only with a 30-cm rootzone layer. Differences were observed in soil pH, EC, OMC, CEC and micronutrients. Soil pH was acceptable for turfgrass growth a year after establishment, being 5.5 to 6.5 in the study. Differences were greatly observed for EC among soil systems. Values of EC for multi-layer, USGA, and mono-layer systems were 39.79, 31.26 and 103.54 uS/em, respectively. The increase rate was approximately 4 to 8 times greater with mono-layer system than those with other two systems. Therefore, it was necessary to avoid micronutrient deficiency such as Fe, Mn etc. through an effective management program in mono-layer system because of its faster potential feasibility of salt accumulation. The greatest OMC was associated with USGA system, being 0.97% which was 11% over that of the other systems. Slight differences were observed for CEC among them. Mono-layer system produced 1.45 me/100g, 10.3% and 8.9% lower in CEC than those of multi-layer and USGA system, respectively. Micronutrients such as Fe, Zn, and Mn etc. were below the level required for turf growth, regardless of soil systems. It was considered that one year after turf establishment was not enough to build up micronutrients in sand-based soil systems to the normal level for a turf growth. These results demonstrate that intensive management program including grow-in concept fertilization should be integrated into sand-based soil systems, even after a year in establishment. Regular nutrient monitoring by soil analyses is a strong necessity to decide the kinds and amount of fertilizer. Also, strategic management program must be selectively employed according to sports turf soil systems.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.4
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• pp.345-352
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• 2020

To preserve and restore tidal flats and prevent safety accidents, it is necessary to construct tidal flat topographic information including the exact location and shape of tidal creeks. In the tidal flats where the field surveying is difficult to apply, airborne LiDAR surveying can provide accurate terrain data for a wide area. On the other hand, we can economically obtain relatively high-resolution data from UAV (Unmanned Aerial Vehicle) surveying. In this study, we proposed the methodology to generate high-resolution topographic information of tidal flats effectively by integrating airborne LiDAR and UAV point clouds. For the purpose, automatic ICP (Iterative Closest Points) registration between two different datasets was conducted and tidal creeks were extracted by applying CSF (Cloth Simulation Filtering) algorithm. Then, we integrated high-density UAV data for tidal creeks and airborne LiDAR data for flat grounds. DEM (Digital Elevation Model) and tidal flat area and depth were generated from the integrated data to construct high-resolution topographic information for large-scale tidal flat map creation. As a result, UAV data was registered without GCP (Ground Control Point), and integrated data including detailed topographic information of tidal creeks with a relatively small data size was generated.

• Economic and Environmental Geology
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• v.43 no.4
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• pp.371-379
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• 2010

Fresh water injection test in a fractured bedrock aquifer was applied as an efficient approach to lower saline concentrations in the saltwater-freshwater transition zone formed by seawater intrusion in a coastal area. The methodology and effectiveness of fresh water injection for hydraulically controlling seawater intrusion is overwhelmingly site dependent, and there is an urgent need to characterize the permeable fractures or unconsolidated porous formations which can allow for seawater flow and transport. Considering aquifer characteristics, injection and monitoring boreholes were optimally designed and completed to inject fresh water through sand layer and fractured bedrock, respectively. We devised and used the injection system using double packer for easy field operation and maintenance. Overall fracture distribution was systematically identified from borehole image logs, and the section of fresh water injection was decided from injection test and monitoring. With fresh water injection, the fluid electrical conductivity of the monitoring well started to be lowered by the inflow of fresh water at the specific depth. And this inflow leaded to the replacement of the fluid in the upper parts of the borehole with fresh water. Furthermore, the injection effect lasted more than several months, which means that fresh water injection may contribute to the mitigation of seawater intrusion in a coastal area.

• Korean Journal of Weed Science
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• v.6 no.2
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• pp.134-145
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• 1986

The experiment was crried out to evaluated the herbicidal properties of bensulfuron methyl [methyl 2-[[[[[(4, 6-dimethoxy pyrimidine-2yl) amino] carbonyl] amino] sulfonyl] methyl] benzoate]. No phytotoxicity was observed when bensulfuron methyl was applied at 3 and 6 g a.i./ 10a while the application rate 12 g a.i./10a slightly retared the growth of rice. The phytotoxicity decreased as the application time was delayed. The effect of application rate, leaching grade, transplanting depth, soil type and temperature on crop injury was little. Japonica variety (Dong-Jin) was more sensitive to bensulfuron methyl than indica X japonica variety (Sam-Kang). Bensulfuron methyl controlled effectively perennial weeds such as Sagittaria pygmaea Miq., Potamogeton diatinctus A. Benn., Cyperus serotinus Rottb., Sagittaria trifolia L., Eleocharis kuroguwai Ohwi. including most annual weeds except Echinochloa crus galli P. Beauv. The effect slightly decreased with lowering the temperature increasing the leaching grade. Application time and soil type employed did not affect the weeding effect.

• Journal of The Korean Association For Science Education
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• v.33 no.5
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• pp.1021-1040
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• 2013

In order to explore the influences of coteaching through mentoring upon the teaching professionalism of beginning science-gifted education teachers, this case study deeply investigated the change processes in the aspects of pedagogical content knowledge (PCK). Two beginning teachers planned, performed and reflected together their science instructions for science-gifted students in secondary school during four 3-hour classes. Since the second instruction, pre-, during-, and post-mentoring were conducted, we collected various data related to teachers' planning processes, videotaped all coteaching science classes, and wrote field notes. We also recorded in-depth interviews with the teachers and the whole process of mentoring. All the data were analyzed by using the constant comparative method. The results of the analyses indicated that coteaching through mentoring positively changed the teachers' PCK. Above all, we found that coteaching and mentoring strategies generated a significant synergy effect through a mutually complementary relationship. The teachers developed deep practical knowledge about the enrichment curriculum, which placed more emphasis on developing cognitive and/or affective characteristics of science-gifted students. The teachers also improved their knowledge about the characteristics of science-gifted students and the instructional strategies appropriate for developing them. Moreover, practical knowledge about assessment domains and methods used in science-gifted education were improved. Knowledge on science content necessary for effective inquiry instruction was also improved.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.6
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• pp.1045-1058
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• 2017

This paper is a study on railway tunnel behavior characteristic of shallow overburden under the existing road. In order to understand the behavior characteristics of the ground deformation during tunnel excavation, a horizontal rod extensometers were installed in the passage area of the shallow overburden tunnel under the road, and the measurement and analysis were carried out. To compare the in situ measurement, three dimensional numerical analysis with ground condition and construction step was carried out using MIDAS NX. As a result of the field measurement, large preceding settlement occurred where the poor ground condition with shallow overburden excavation has been conducted. As a result of the numerical analysis, the largest settlement occurred at the shallow overburden point where the ground condition was poor. Therefore, in the shallow overburden section where the soil condition is poor and a sufficient depth can't be secured and the arching effect of the ground around the tunnel can't be expected, careful attention should be paid to the application of stiffness reinforcement measures and to minimize ground loosening.

• Journal of the Korean Geosynthetics Society
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• v.16 no.2
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• pp.35-45
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• 2017

Gravel compaction pile (GCP) is widely used as it increases the bearing capacity of soft ground and reduces the consolidation settlement. Stress concentration ratio for design is dependent on the area replacement, surcharge pressure, depth and penetration rate. However, a range of stress concentration ratio obtained through field, laboratory experiments and numerical analysis is large. But since the main objective of the study is to evaluate the stress concentration ratio and settlement for both area replacement ratio and penetration rate through numerical analysis. Numerical analysis using the finite element program ABAQUS 6.12-4 has been performed for the composite ground with GCP. As a result, the stress concentration ratio at the points except for the point of top is in the range of 1.21-5.36, 1.19-5.45, 2.16-5.60 for 60%, 80% and 100% penetration, respectively. In general, as the penetration rate and area replacement ratio increases, the stress concentration ratio tends to increase.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.4
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• pp.284-288
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• 2009

With explosively growing PPI databases, the computational approach for a prediction and configuration of PPI network has been a big stream in the bioinformatics area. Recent researches gradually consider physicochemical properties of proteins and support high resolution results with integration of experimental results. With regard to current research trend, it is very close future to complete a PPI network configuration of each organism. However, direct applying the PPI network to real field is complicated problem because PPI network is only a set of co-expressive proteins or gene products, and its network link means simple physical binding rather than in-depth knowledge of biological process. In this paper, we suggest a protein functional flow model which is a directed network based on a protein functions' relation of signaling transduction pathway. The vertex of the suggested model is a molecular function annotated by gene ontology, and the relations among the vertex are considered as edges. Thus, it is easy to trace a specific function's transition, and it can be a constraint to extract a meaningful sub-path from whole PPI network. To evaluate the model, 11 functional flow models of Homo sapiens were built from KEGG, and Cronbach's alpha values were measured (alpha=0.67). Among 1023 functional flows, 765 functional flows showed 0.6 or higher alpha values.

• The Journal of the Korea Contents Association
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• v.19 no.9
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• pp.67-80
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• 2019

Augmented Reality (AR) is a crucial technology in the Fourth Industrial Revolution that can revolutionize the existing Information and Communication Technology (ICT) market and powerfully create a new market However, it is hard to find the clear answer for AD/PR strategies in the rapidly changing AR market. Thus this research explores the big picture of the AR industry as it pertains to Politics, Economy, Social, and Technology through in-depth interview with seven AR experts who are leading the domestic AR market. The research also analyzes the AR market's Strengths, Weaknesses, Opportunities, and Threats. Furthermore, it looks for strategies to vitalize the advertising and PR industry by analyzing the Contents, Platform, Network, and Devices of the AR ecosystem. The results of the research indicate a need for the government's strengthened policy of supporting the AR market, fostering of pace-setting killer contents, connecting services of several industries through AR platforms, strengthening the network of communication systems such as through 5G, and the commercialization and industrialization of domestic devices in order to vitalize the AR industry in its marketing and PR spheres. Therefore, this research suggests measures to revitalize the marketing and PR industries of the AR ecosystem, which has only recently gotten to its developing stage and provides an academic as well as practical foundation for future research in the field of AR.

• International Area Studies Review
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• v.18 no.3
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• pp.231-248
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• 2014

The relationship between market structure and social welfare outcomes has received considerable critical attention in the field of competition policy research. In particular, it is necessary to study in greater depth the impact of market power on social welfare in the telecommunications industry, which is highly likely to form a monopolistic market structure. This is because, when market powers are concentrated on few upper carriers, there are negative effects on social welfare due to an excess of profits. Against this background, the present study investigates the relationship between the market structure of the mobile communications industry (the level of market power) and social welfare outcomes (the retail rate cut) through an international comparison. The results demonstrate that both the market structure and competition status of the Korean market have had significant gaps in global trends. It also points out that the monopolistic market structure (when the leading provider has more than 50% of the market share) has significantly negative effects on consumer welfare (the retail price cut). In addition, the findings of this study suggest that the direction of competition policy should focus on not only improving market concentration(HHI), but also on mitigating the monopoly of power of a dominant operator.