• Journal of the Earthquake Engineering Society of Korea
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• v.24 no.5
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• pp.197-209
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• 2020

Evidence of liquefaction during the 2017 Pohang earthquake has highlighted the urgent need to evaluate the current seismic design standard for liquefaction in Korea, particularly the liquefaction triggering standard. With the simplified method, which is the most popular method for evaluating liquefaction triggering, the factor of safety for liquefaction triggering is calculated via the cyclic stress ratio (CSR) and the cyclic resistance ratio (CRR). The parameters in the CSR and CRR have undergone changes over time based on new research findings and lessons learned from liquefaction case-histories. Hence, the current design standard for liquefaction triggering evaluation in Korea should also reflect these changes to achieve seismic safety during future earthquakes. In this study, liquefaction susceptibility criteria were discussed initially and this was followed by a review of the current liquefaction triggering codes/guidelines in other countries and Korea. Next, the parameters associated with the CSR such as the maximum ground acceleration, stress reduction factor, magnitude scaling factor, and overburden correction factor were discussed in detail. Then, the evaluation of the CRR using the SPT N-value and CPT qc-value was elaborated along with overburden and clean-sand correction factors. Based on this review of liquefaction triggering evaluation standards, recommendations are made for improving the current seismic design standard related to liquefaction triggering in Korea.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.5
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• pp.645-654
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• 2018

Extreme rainfall events caused severe damage to human life and property due to the inundation in major urban areas. In particular, the increase in the intensity of rainfall due to climate change causes changes in the design flood discharge. As a result, it causes uncertainty in the design criteria of hydraulic structures. However, quantitative analysis results have not been provided due to the limitations of climate scenarios and the uncertainty in climate changes. Therefore, this research chose Bulgwangcheon basin as the target basin to analysis the discharge considering climate change. As the result, it is necessary to strengthen design standards since the amount of discharge increased by 14.2% even in the near future.

• International Journal of High-Rise Buildings
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• v.6 no.3
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• pp.279-284
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• 2017

The purpose of structural health monitoring is to evaluate structural behavior due to various external loads through installation of appropriate measurement. Accordingly, a guideline for monitoring standards is necessary to evaluate the safety and performance of a structure. This paper introduces preliminary design of SHM for high-rise buildings, which is the stage creating a guideline. As for preliminary design of SHM, first step is to calculate the displacement and member force through structural analysis. After that, limitations or qualifications are proposed for management. Secondly, based on the results from first step, issues related monitoring such as monitoring method, measurement type, or installation location are determined. This method leads building managers to reasonably define the structural safety over the whole life cycle. Furthermore, this experience contributes to development of SHM forward and it is expected to be useful for other types of structures as well such as spatial structures or irregular buildings.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.162-170
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• 2021

The Smart City Living Lab is becoming important as a local innovation platform to develop urban solutions. In January 2018, the 4th industrial innovation committee, which was a direct subordinate from the president, empathized citizens' participation and their roles within the Smart City [Urban Innovation and Future Growth Engine-Creating Smart City Strategy]. This was the starting point of the living lab. The central government and local governments have been promoting various types of living labs to encourage citizens to participate. On the other hand, due to the lack of systematic concepts and theories for practicing and structuring living labs, the practice is not performed well. This study aimed to develop systematic approaches and implementation methods of the public-led Smart City Living Lab. The Full-cycle Smart City living Lab model was designed by integrating smart city living lab work processes, as suggested in the standards of the national land plan, double design diamond framework, which is a type of innovative design methodology, and design thinking process. The entire cycle Smart City living lab model requires four components to practice the living lab, such as framework, module, process, and methodologies. In the future, this model is expected to be incorporated in the Smart City Living Lab.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.1D
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• pp.101-110
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• 2009

Urban Designers and Planners are interested in creating barrier-free (BF) environments as the demand for social equity increases. BF design consists of design strategies for modifying buildings or facilities to be used by the physically disadvantaged or disabled. To construct buildings or facilities to be "Barrier-free", design standards specifically modified for the physically disadvantaged or disabled should be applied. The purpose of this study is to analyze the BF design standard used in the national laws and provide suggestions for their future improvements. In the study national laws in four countries were reviewed and important BF standards to be used in the laws were identified using a frequency analysis. The results of the frequency analysis were applied to the BF assessment criteria for sidewalk design. Then a field assessment for two sidewalks located in Seoul metropolitan region was conducted using the refined BF criteria. The findings from the field assessments indicated that current regulations were not appropriately designed to provide sufficient convenience for the disabled. It is needed to enhance the BF standards in the domestic regulations to offer sufficient mobility to the physically disadvantaged or disabled.

• Journal of Korean Society on Water Environment
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• v.38 no.5
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• pp.220-230
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• 2022

Seasonal variability of water quality in the upland headwater streams in ten forested catchments (37.0~209.0 ha) was examined from April to November 2021. Here, seven physicochemical parameters were analyzed including pH, electrical conductivity (EC), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen (T-N), total phosphorous (T-P), and BOD/TOC. The parameters were compared with those of lowerland rivers as middle and lower reaches within a watershed. The pH showed was low (6.4~6.9) during all the seasons, however, BOD and BOD/TOC in the fall season were 2-fold higher than in the spring and summer seasons. Based on environmental standards, the water quality level revealed that the upland headwater streams maintained the purity and cleanliness of water except for pH in the summer season. BOD/TOC of all the seasons and BOD of the fall season in the upland headwater streams were higher than that in the lowerland rivers, whereas the rest of the physicochemical parameters in the upland headwater streams were lower than that in the lowerland rivers. Additionally, the water quality level maintained the purity and cleanliness of water as "Good" in two reaches. The unique aspects of our study design enabled us to draw inferences about water quality characteristics with temporal and spatial analysis in upland headwater streams. This design will be useful for the long-term strategy of effective water quality management for integrated upland headwater streams and lowerland rivers within a watershed.

• Journal of Communications and Networks
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• v.8 no.4
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• pp.369-377
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• 2006

Recently, the metropolitan area network (MAN) has attracted much attention in telecommunication research and has emerged as one of the most important research topics in the community. Several standards representing the first step for developing metropolitan networks have been published; IEEE 802.16 (WiMAX) has taken a relevant role in reaching the goal of realizing a full-service network all over a urban and suburban area. At the same time, the wireless local area networks (WLAN) have been widely used for in-home or short range communications, mainly basing on the IEEE 802.11 (WiFi) standard. A consequence is the increasing interest in interworking technology, that allows an interconnection between different standards by maintaining certain properties, mainly in terms of quality of service (QoS). One of the major issues is to design bridging devices capable of transparently interconnect different wireless technologies. In this paper, we propose two interconnection bridging solutions between WiMAX and WiFi links; the first is more based on the concept of maintaining a certain end-to-end QoS level independently from the wireless technologies used. The second method is more devoted to the reduction of the implementation complexity at the cost of no QoS assurance. The performance of the two methods are compared by resorting to computer simulations showing the advantages of each one technique.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.1
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• pp.37-47
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• 2000

This research focused on the improved alternatives of the ordinance which practically control the open space in-situ, public open space and landscape construction related to city landscape for the healthy physical and mental life of the city dwellers. The contents of the study are as follows: 1. The special law of Landscape Architecture should be legislated. 2. The portion of landscaping should be changed by up-grading in the Ordinance of Landscape area and planting and the terms of landscape Facilities should include the ecological aspects in it's contents in the law. 3. The administration of local governments should actively lead and support the dwellers to make the roof gardens and the window gardens in the building area of cities or commercial districts which have relatively low rate of green space. 4. Any new construction and restoration of the buildings with preservation of the natural environment and creation of public open space should be given incentive and Set-back space in aesthetic area should have appropriate planting area and facilities in it. 5. Organizing professional landscape evaluation committee and composing evaluation standards are very important because of the contemporary proposition of the establishment of the establishment of ecological space and conservation of urban natural space. Because of the characteristics of Landscape Architecture, the Provisions of landscape Architecture Design and landscape architecture supervision of the specialist should be legislated and the Landscape Architectural Organization should be established within the Government.

• KIEAE Journal
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• v.8 no.3
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• pp.27-36
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• 2008

Urban architecture density is getting higher, and this trend is expected to continue in the future. Therefore, skyscrapers are being brought into relief as future alternative architecture beyond symbolic meaning in the aspect of demand and supply of urban space. However, skyscrapers which were newly built have many problems such as consumption of enormous amounts of energy, destruction of natural environment, and traffic jam. For this reason, environment-friendly skyscrapers based on the concept such as Green Building and Green Skyscraper started to be built around the world. However, plans or evaluation standards, which take account of the environment-friendly aspect of skyscrapers, leave much to be desired. And especially it is hard to find environment-friendly skyscrapers. Therefore, this study aims to establish the concept of environment-friendly skyscrapers that has not properly been defined, and to find realistic planning methods and practical alternatives through the analysis of the works that have brilliant ideas about environment-friendly architectural method. From the perspective of architectural planning, we did case analysis focused on site planning, form planning, elevation and floor planning, and tried to give useful ideas for high-rise architectural planning in Korea by finding practical solution focused on the active use of natural energy, saving resources, the reduction of wastes, natural architectural environment design and natural friendly system from the view of environment-friendly technological analysis.

• KIEE International Transactions on Power Engineering
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• v.3A no.2
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• pp.63-69
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• 2003

The necessity of compact high temperature superconducting cables is more keenly felt in densely populated metropolitan areas. Because the compact high-temperature superconducting cables can be installed in ducts and tunnels, thereby reducing construction costs and making the use of underground space more effective, the effect of introducing it to the power system will be huge. Seoul, Korea, is selected as a review model for this paper. The loads are estimated by scenario based on a survey and analysis of 345kV and 154kV power supply networks in this area. Based on this, the following elements for an urban transmission system are examined. (1) A method of constructing a model system to introduce high-temperature superconducting cables to metropolitan areas is presented. (2) A case study is conducted through the analysis of power demand scenarios, and the amount of high-temperature superconducting cable to be introduced by scenario is examined. (3) The economy involved in expanding existing cables and introducing high-temperature superconducting cables(ducts or tunnels) following load increase in urban areas is examined and compared., and standards for current cable ducts are calculated. (4) The voltage level that can be accommodated by existing ducts is examined.