• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.1
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• pp.112-119
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• 2011

Sheaths are arranged in the web and lower part of prestressed-concrete girder bridges, and prestressing wires and concrete are indirectly bonded together by filling interior parts of the sheaths. However, when the filling is not sufficient, water can penetrate the interior parts of the sheaths and, thereby, prestressing wires can be corroded or transverse cracks would occur around sheaths by the freezing and thawing action of the penetrated water. Therefore, it is an important element in maintenance management of structures to find out the sheaths unfilled with grout early after construction. In this paper, in order not to damage bridge members, the impact-echo method with a new approach in application is used to probe sheaths unfilled with grout for real structures. The location of sheaths is first estimated with reinforcing bar probing instrument of radar type and the measurement locations of sheaths are determined. By sending elastic wave to the side of girders and receiving the response, the location of the unfilled part of a sheath was estimated from the difference between high frequency peak and twice the resonance frequency indicating thickness. To verify the location of void estimated by the impact-echo method, pictures were taken by an industrial fiber scope after drilling a hole.

• Journal of Environmental Impact Assessment
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• v.31 no.4
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• pp.250-264
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• 2022

The development projects subject to health impact assessment (HIA) in the current environmental impact assessment (EIA) system are limited to some projects under Article 12 of the Enforcement Decree of the Environmental Health Act (Additional Assessment Objects Subject to Health Impact Assessment Items), but health impact-related matters are being evaluated and reviewed during consultation. In particular, when a development site is planned around some pollutant sources in a residential development plan, it is evaluated and reviewed whether the site meets the risk criteria through a current concentration survey of major hazardous air pollutants. This study prepared a quantitative method to confirm the validity of the location of the residential area to be developed in the residential development plan and proposed a plan to expand the project subject to HIA within the EIA procedure. A detailed methodology was proposed by reviewing the screening and scoping procedures of the EIA system, and a case analysis of the urban development plan discussed in the past was conducted to verify the methodology.

• Journal of Korea Multimedia Society
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• v.1 no.2
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• pp.249-255
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• 1998

This paper analyzes the impact of Call Setup Time on UPT performance based on the AIN platform. Call Setup Time is used as the performance parameter. In implementing UPT based on the AIN platform, the geographical location of VLR affects network performance. In order to find an optimum location of VLR among three different types of structures, i.e. VLR is located close to Service Switching Point and Cell Site Controller and located at Service Control Point, each Call Setup Time on proposed time delay model is calculated and compared. Network performance is analyzed by changing the number of STP in No.7 signaling network in UPT and the utilization ratio, $\rho$, for SSP, STP and SCP.

• Journal of the Korea Safety Management & Science
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• v.19 no.4
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• pp.157-167
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• 2017

Solar energy has been known as a successful alternative energy source, however it requires a large area to build power generation facilities compared to other energy sources such as nuclear power. Weather factors such as rainy weather or night time impact on solar power generation because of lack of insolation and sunshine. In addition, solar power generation is vulnerable to external elements such as changes in temperature and fine dust. There are four seasons in the Republic of Korea hereby variations of temperature, insolation and sunshine are broad. Currently factors that cause find dust are continuously flowing in to Korea from abroad. In order to build a solar power plant, a large area is required for a limited domestic land hereby selecting the optimal location for the plant that maximizes the efficiency of power generation is necessary. Therefore, this research analyze the optimal site for solar power generation plant by implementing analytic hierarchy process based on weather factors such as fine dust. In order to extract weather factors that impact on solar power generation, this work conducts a case study which includes a correlation analysis between weather information and power generation.

• Journal of Environmental Impact Assessment
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• v.28 no.4
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• pp.413-426
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• 2019

Many factories indiscriminately located in the vicinity of residential areas need to be adjusted to quasi-industrial parks or new planning management area. In the present work, the changes of atmospheric $SO_2$ concentration according to clustering of individual location factories throughout Gimpo city into a new area were evaluated using a commercial dispersion model, AERMOD. As a result of the evaluation, it was suggested the possibility of improving the pollution through the relocation of individual factories. The combination of relocation and discharge regulation on the stack height may reduce the overall pollution from Gimpo approximately up to 70%, and some areas achieve maximum 87% decrease. However, the area selected as a cluster zone may show a relatively large increase compared to the change in the total pollution level of Gimpo.

• Journal of the Korean Society of Safety
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• v.32 no.3
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• pp.41-47
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• 2017

Recent studies have shown that there are various systems which can be used to monitor hazardous area in a debris flow location, but lack of methodological research on the exact location where each instrument should be installed has hindered the success of this systems. The objective of this study is to suggest the measurement system for monitoring debris-flow and propose the effective method to determine location of measurement system. Previously studied, from 1991 to 2015, were referred and the applied ratio of every instrument was investigated. The measurement information was divided into 8 categories including rainfall, debris-flow velocity, displacement, fluid pore pressure, ground vibration, image processing, impact force and peak flow depth. The result of this study revealed that the most applied instruments to be rain gauge and geophone for measuring average rainfall and ground vibration respectively. The Analytic Hierarchical Process (AHP) method was selected to determine installation location of instrument and the weighting factors were estimated through fine content, soil thickness, porosity, shear strength, elastic modulus, hydraulic conductivity and saturation. The soil thickness shows highest weights and the fine content relatively demonstrates lowest weights. The score of each position can be calculated through the weighting factors and the lowest score position can be judged as the weak point. The weak point denotes the easily affecting area and thus, the point is suitable for installing the measurement system. This study suggests a better method for safely managing the debris-flow through a precise location for installing measurement system.

• Journal of the Korean association of regional geographers
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• v.17 no.2
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• pp.216-230
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• 2011

Coal briquette manufacturers once served as major fuel suppliers for households. For the coal briquette industry, transportation accounts for a considerable portion of the total manufacturing cost as briquettes are heavy in weight but low in value-addition. Moreover, they were put under strict control by the government for the characteristics of the briquettes as public goods. This study intends to identify the factors of and the types of the location of coal briquette manufacturing industry. In particular, the focus of the study is the briquette manufacturers in Seoul. Moreover, this study aims to identify how government policy influenced the location of the industry. The coal briquette manufacturing industry in the example regions were oriented toward the market and trans-shipment points. Simultaneously, the industry underwent spatial changes due to the spatial policy. While derived spatial policies were significant factors for growth of coal briquette industry, explicit spatial policies only modified or facilitated some of the location features resulting from the characteristics of the industry.

• The Journal of the Korea Contents Association
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• v.18 no.10
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• pp.279-288
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• 2018

Unlike the past, the elderly who are growing rapidly in Korea are called 'active seniors'. They prefer to live in urban silver towns despite high living cost and make their own new urban contents. The new urban contents that reflect the living characteristics of active seniors have an important impact on their choice of residential location. Therefore, the purpose of this study is to identify the location characteristics of urban silver towns, which are preferred as the main residence of active seniors, based on the urban living contents of active seniors. The location characteristics of urban silver towns considering the urban living contents of active seniors can be classified 1) public transportation, 2) nearby arterial roads, 3) culture shopping facilities, 4) medical facilities, 5) apartment complexes, and 6) natural environments. Especially, the accessibilities of medical facilities, apartment complexes, and culture shopping facilities were the main characteristics of urban silver towns. The results of this study are expected to be helpful not only the location of urban silver towns, which is the urban new content of active senior, but also for the policy on housing for the elderly.

• Journal of Korea Port Economic Association
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• v.31 no.1
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• pp.127-145
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• 2015

Plant location selection is a decision which requires huge investment and entails a significant impact in a longer-term. The petrochemical industry, in particular, is so capital- and technology-intensive that the firms in the industry pursue enhancing competitiveness through collaboration and integration among entities in their supply chains. Even though the logistics factor such as logistics costs and connectivity have, as a result, gained its importance in plant location decision making, this has rarely studies in empirical studies. Therefore, this study aims to examine the relative importance of the logistics factor in plant location decision making in the petrochemical industry using the multi-criteria decision-making approach. In addition the three representative petrochemical industrial complexes are evaluated by the factors used in this study. This study is able to provide the useful implication in both practical and policy-making aspects. Firms are required to consider the logistics factors with priority compared to other factors in plant location decision making. In addition, when federal or local governments build industrial sites and attract the petrochemical firm, logistics infrastructure should also be considered to provide better transportation connectivity and lower logistics costs in turn.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.1
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• pp.64-77
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• 2022

The advent of location-based social networks (LBSNs), and the pervasive use of smartphones have allowed individuals to easily inform their status through locational information. This led to a new trend in social media: to upload geotagged photos that illustrate the location of the images and then share them with others. In this circumstance, the current study aims to examine the use of geotags on Instagram. Further, the motivations for using geotags as well as the relationship among the motivation, satisfaction, and location information sharing behavior are analyzed. The online survey was conducted on 411 respondents of Hong Kong who are active Instagram users. Based on uses and gratification theory and goal theory, the users' motivations and goals for utilizing geotags were divided into mainly two categories; task-involved and self-involved goals. Then, four different motivations (contribution, memory aid, showing off, and reputation gaining) were further examined. The result indicated that contribution, memory aid, and reputation gaining were the goals and motivation for the users to utilize geotags on Instagram, having a positive impact on satisfaction. However, a positive relationship between showing off and geotag satisfaction was not supported. Among four different factors, memory aid was found to have the strongest influence on geotagging satisfaction. The result of testing the relationship between geotag satisfaction and further location information sharing behavior also turned out to have a positive relationship. The implications and limitations of findings are also discussed in the study.