• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.1
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• pp.42-53
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• 2021

Street trees improve the cityscape and air quality, reduce heat islands, and create wildlife habitats. Hence, they are essential parts of a city's green infrastructure. Therefore, several trees that are well adapted to the urban environment were planted. However, this caused the problem of simple trees being planted around the world. This study is to select more various street trees. To accomplish this, evaluation criteria and detailed indexes were created. The importance was indicated through the Analytic Hierarchy Process. For commercial roads, the priority of landscape characteristics is 0.2640, and among detailed indicators, the priority of shape is 0.1245. For work roads, the priority of landscape characteristics is 0.2496, and among detailed indicators, the priority of shape is 0.1177. For work roads, the priority of characteristics of civil service is 0.2250, and among detailed indicators, the priority of shape is 0.1177. For general roads, the priority of maintenance characteristics is 0.2479, and among detailed indicators, the priority of shape is 0.1062. For historical and cultural roads, the priority of regional characteristics is 0.3488, and among detailed indicators, the priority of regional characteristics is 0.1643. For ecological roads, the priority of ecosystem characteristics is 0.3488, and among detailed indicators, the priority of the diversity of species is 0.1643. For automotive-only roads, the priority of the ecosystem characteristics is 0.4639, and among detailed indicators, the priority of reducing emissions is 0.1643. This study will provide objective criteria for the selection of street trees.

• Korean Journal of Plant Resources
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• v.34 no.1
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• pp.44-51
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• 2021

Centella asiatica (L.) Urban is a medicinal plant containing madecassic acid, triterpenoids and asiaticoside, and has a wound healing effect. However, since it grows only in some regions of Korea, it is necessary to breed stable varieties. In this study, it were analyzed for the growth characteristics, asiaticoside, anxiodant components and 2,2-diphenyl-1picryl hydrazyl (DPPH) radical scavening activity of C. asiatica collected from domestic natural habitat (Hapcheon, Gyeongnam). In the growth characteristics of each resource, CA9 and CA10 were superior in characteristics of aerial part and in dry weight. In asiaticoside content analysis, CA5 and CA3 were high with 53.96 mg/g and 52.40 mg/g, respectively. CA12 showed the possibility of development because the resource showed high in total flavonoid (7.3 mg/g), total polyphenol (10.64 mg/g) and DPPH activity (11.96 mg AAE/g) among other resources. However, it is necessary to select a resource suitable for each characteristic of C. asiatica and to study charateristics through additional resources collection since the excellent growth characteristics of the collected resources do not necessarily coincide with the content and antioxidant activities.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.12
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• pp.969-976
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• 2020

Urban Air Mobility is attracting attention as a future innovation industry around the world, and leading industries are considering the application of composite materials for structural robustness and lightening in the designing and manufacturing new concept eVTOL aircraft. To apply composite materials to the new concept of eVTO aircraft, this paper was analyzed about composite material qualification system of FAA & EASA and institutionalized by Korea Government, including the procedures and methods, the organization to carry out the material verification for domestic conditions. The domestic composite material qualification system will not only make it easier for manufacturers of eVTOL aircraft with a new concept to apply composite materials to domestic aircraft through pre-material qualification, but also reduce the burden of material qualification within the period of type certification. In addition, domestic manufacturers of composite materials with qualified material quality and performance will be easy to enter for domestic aircraft applications and composite material manufacturers with experience in applying to aircraft will have a positive impact on overseas exports. This system will be able to promote the development eVTOL aircraft industry of a new concept and enhance international credibility of made aircraft in Korea.

• Journal of Korea Water Resources Association
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• v.55 no.1
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• pp.71-84
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• 2022

The objective of this study is to develop a two-dimensional (2D) flood model that can perform accurate flood analysis with simple input data. The 2D flood inundation models currently used to create flood forecast maps require complex input data and grid generation tools. This sometimes requires a lot of time and effort for flood modeling, and there may be difficulties in constructing input data depending on the situation. In order to compensate for these shortcomings, in this study, a grid-based model that can derive accurate and rapid flood analysis by reflecting correct topography as simple input data was developed. The calculation efficiency was improved by extending the existing 2×2 sub-grid model to a 5×5. In order to examine the accuracy and applicability of the model, it was applied to the Gamcheon Basin where both urban and river flooding occurred due to Typhoon Rusa. For efficient flood analysis according to user's selection, flood wave propagation patterns, accuracy and execution time according to grid size and number of sub-grids were investigated. The developed model is expected to be highly useful for flood disaster mapping as it can present the results of flooding analysis for various situations, from the flood inundation map showing accurate flooding to the flood risk map showing only approximate flooding.

• Explosives and Blasting
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• v.39 no.4
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• pp.22-33
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• 2021

Recently, the frequent occurrence of ground subsidence in urban areas has caused increasing anxiety in residents and incurred significant social costs. Among the causes of ground subsidence, the rupture of old water and sewer pipes not only halts the operation of the buried pipes, but also leads to ground and water pollution problems. However, because most pipes are buried after construction and cannot be seen with the naked eye, the importance of maintenance has underestimated compared to other structures. In recent years, integrated physical exploration has been applied to the maintenance of underground pipes and structures. Currently, to investigate the internal conditions and vulnerable portions of the ground, consolidated physical surveys are executed. Consolidated physical surveys are analysis techniques that obtain various material data and add existing data using multiple physical surveys. Generally, in geotechnical engineering, consolidated physical surveys including electrical and surface wave surveys are adopted. However, it is difficult to investigate time-based changes in under ground using these surveys. In contrast, surveys using cosmic-ray muons have been used to scan the inner parts of nuclear reactors with penetration technology. Surveys using muons enable real-time observation without the influence of vibration or electricity. Such surveys have great potential for available technology because of their ability to investigate density distributions without requiring as much labor. In this paper, survey technologies using cosmic ray muons are introduced, and the possibilities of applying such technologies as new physical survey technologies for underground structures are suggested.

• Land and Housing Review
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• v.13 no.1
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• pp.67-84
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• 2022

This study aims to investigate the value of greenbelts exploring how they can be linked with green infrastructure networks. This research interprets the results of geographical information system (GIS) analysis differently from a conventional approach. The findings of the research are four-fold based on the analysis of the Daejeon Metropolitan Area. First, the most controversial greenbelts are laid on Yuseong-gu because the relaxation of the greenbelts for new housing development has caused outstanding issues since the early 2000s. Decisions on further relaxation or restoration of the greenbelts, which will provide a new direction for the establishment of green infrastructure networks, should be made through accurate environmental assessments. Second, the connected north-south corridors of large cities will affect the greenbelts not only in Daejeon, but also in the entire Chungcheong Provinces, and surrounding local municipalities, which should be considered for the revision of the greenbelt policy. Third, it is expected to experience growing development pressures towards neighboring municipalities due to the ongoing strict greenbelt policy. Among them, the most likely areas are Sejong City to the north and Nonsan to the south, requiring policy measures. Fourth, the value of green infrastructure should be added to current evaluation criteria rather than a binary approach - relaxing or preserving the greenbelts - to be holistically integrated with a metropolitan plan.

• Journal of Cadastre & Land InformatiX
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• v.51 no.2
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• pp.107-123
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• 2021

In recent years, due to the continuous density and urbanization of space, the expansion of awareness of rights, the need for landscape conservation, and the development of construction technology, the conventional flat land use has been deviated from the conventional flat land use, and the transmission line, urban railway, parking lot, communal district, underground shopping mall, pipeline, etc. Although 3D spatial activities are carried out in the form of 3D space, there are considerable difficulties in administration to manage the 3D use of land due to the inadequacy of related regulations. In this background, for the administration that can manage Sectional Superficies, which is a representative case of 3D spatial use of parcels, which is a registered unit of land, first, the law on the establishment and management of spatial information, and cadastral re-examination from the legal and institutional aspects Standardization of 3D space registration through amendments to the Special Act, etc. and the formation of consensus among related departments. Second, in technical and administrative aspects, the registration of Sectional Superficies based on cadastral survey results, establishment of a platform for integrated management of location and attribute data, and registration method was found to be in need of improvement. As suggested in this study, by registering and managing Sectional Superficies, it is possible to manage various 3D land use of not only ground space or surface space but also underground space. It is expected to be able to register and manage lot-based 3D land use efficiently.

• Korean Journal of Remote Sensing
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• v.38 no.5_3
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• pp.851-861
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• 2022

In this study, we analyzed the effects of trees planted in urban areas on PM_2.5 reduction using a computational fluid dynamics (CFD) model. For realistic numerical simulations, the meteorological components(e.g., wind velocity components and air temperatures) predicted by the local data assimilation and prediction system (LDAPS), an operational model of the Korea Meteorological Administration, were used as the initial and boundary conditions of the CFD model. The CFD model was validated against, the PM_2.5 concentrations measured by the sensor networks. To investigate the effects of trees on the PM_2.5 reduction, we conducted the numerical simulations for three configurations of the buildings and trees: i) no tree (NT), ii) trees with only drag effect (TD), and iii) trees with the drag and dry-deposition effects (DD). The results showed that the trees in the target area significantly reduced the PM_2.5 concentrations via the dry-deposition process. The PM_2.5 concentration averaged over the domain in DD was reduced by 5.7 ㎍ m^-3 compared to that in TD.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.6
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• pp.154-160
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• 2021

Recently, there have been increasing construction works carried out in urban centers, which are inducing frequent artificial vibration in the vicinity of existing structures due to such construction works. moreover, in case of industrial estates, vibration is induced due to operation of machines in the surrounding areas, thereby causing problems. meanwhile, in case of ordinary concrete that compose structure has low level of damping capability for vibration. accordingly, there are difficulties in blocking a wide range of vibrations delivered to the structures from outside including not only vibrations generated in the structures themselves but also ground vibration. recently, numerous studies are being carried out actively on high-damping system that markedly enhanced the damping performances of structures by utilizing polymer concrete in order to block the vibrations delivered to the structures through ground. therefore, this study compared the performances of polymer concrete with those of ordinary concrete, polyurethane pad and foamed rubber pad in order to review its performances in reducing ground vibration. for this purpose, review of FRF and vibration acceleration as dynamic characteristics was made. after comparative verification on the dynamic characteristics is made when polymer concrete and other aforementioned materials are applied to underground structures, the possibility of application of polymer concrete to structures is reviewed.

• Korean Association of Arts Management
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• no.56
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• pp.243-274
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• 2020

Maker culture in Korea began to receive public attention after the 2012 Maker Fair Seoul. Central and local governments took note of this trend and subsumed makers' culture into its policy domains such as Creative Industry, Creative Cities, 4th Industrial Revolution, and the all-encompassing Creative Economy. Creative Economy was a public policy discourse formed in the public sector for the purpose of overcoming economic depression and revitalizing the economy. Under Creative Industry and Creative Economy, creativity and culture/arts are deemed indispensable but at the same time objectified and alienated as their ultimate value are recognized only as the basis for economic production. In this article, makers' culture itself goes through the same process of objectification and alienation that creativity and culture/arts suffered as the relevant policies were pursued under Creative Economy. The authors attempted to corroborate this through the case of Makercity Sewoon, and found that the Seoul City's urban development plan surrounding Sewoon Plaza proceeded in a direction destructive to the local technological ecosystem and therefore conflicts with the pronounced goal of leading 4th Industrial Revolution by encouraging and nurturing makers' culture. Makercity Sewoon, although packaged in a discourse of Creative Economy and Creative City, betrayed the same problem of alienating arts/culture and labor that the previous discourse showed.