• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.6
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• pp.227-237
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• 2015

From January 2013 to October 2015, weed invasion control techniques was tested in the test road of Jungbunaeryuk expressway so as to collect preliminary data for the management methods of the upper exterior banking of expressway shoulders. Then, monitoring was conducted and its results are as follows. Mat (sheet), solidifying agent, and mulching (wood chips) were applied for the test and their initial effects of preventing weed invasion were all excellent. It was found that the homogeneity of the wood chip mulching method needs to improve. In the mat method and the mulching method were found to have the most excellent economic feasibility and aesthetics, respectively. The covering degree was found to be the highest at 80% in the control site, followed by the wood chip site at 20% and the solidifying agent site and the non-woven fabric site at 5% each. As for species diversity, the control had the largest variety of species. Two years after the construction, many different species of plants invaded and were growing. Plants including weed didn't tend to invade the slopes applied with non-woven fabric. In addition, weed didn't invade the solidifying agent site and the aesthetics of the upper exterior banking of expressway shoulders was found to be excellent. The wood chip site was found to require consistent management for preventing weed invasion. The mat (sheet) site, the solidifying agent site, and the wood chip mulching site were found to have excellent weed prevention effects. As time passed, the mat (sheet) site and the solidifying agent site showed better weed prevention effects. However, they need consistent monitoring for further application.

• Journal of Soil and Groundwater Environment
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• v.25 no.2_spc
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• pp.28-54
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• 2020

Even though a systematic sampling approach is very crucial in both the general and detailed investigation phases to produce the best conceptual site model for contaminated sites, the concept is not yet established in South Korea. The U.S. Environmental Protection Agency (EPA) issued the 'Strategic Sampling Approaches Technical guide' in 2018 to help environmental professionals choose which sampling approaches may be needed and most effective for given site conditions. The EPA guide broadly defines strategic sampling as the application of focused data collection across targeted areas of the conceptual site model (CSM) to provide the appropriate amount and type of information needed for decision-making. These strategic sampling approaches can prevent the essential data from missing, minimize the uncertainty of projects and secure the data which are necessary for the important site-decisions. Furthermore, these provide collaborative data sets through the life cycle phases of projects, which can generate more positive proofs on the site-decisions. The strategic sampling approaches can be divided by site conditions. This technical guide categorized it into eight conditions; High-resolution site characterization in unconsolidated environments, High-resolution site characterization in fractured sedimentary rock environments, Incremental sampling, Contaminant source definition, Passive groundwater sampling, Passive sampling for surface water and sediment, Groundwater to surface water interaction, and Vapor intrusion. This commentary paper introduces specific sampling methods based on site conditions when the strategic sampling approaches are applied.

• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.4
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• pp.245-256
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• 2016

In the companion paper (I - Database and Site Response Analyses), site-specific response analyses were performed at more than 300 domestic sites. In this study, a new site classification system and design response spectra are proposed using results of the site-specific response analyses. Depth to bedrock (H) and average shear wave velocity of soil above the bedrock ($V_{S,Soil}$) were adopted as parameters to classify the sites into sub-categories because these two factors mostly affect site amplification, especially for shallow bedrock region. The 20 m of depth to bedrock was selected as the initial parameter for site classification based on the trend of site coefficients obtained from the site-specific response analyses. The sites having less than 20 m of depth to bedrock (H1 sites) are sub-divided into two site classes using 260 m/s of $V_{S,Soil}$ while the sites having greater than 20 m of depth to bedrock (H2 sites) are sub-divided into two site classes at $V_{S,Soil}$ equal to 180 m/s. The integration interval of 0.4 ~ 1.5 sec period range was adopted to calculate the long-period site coefficients ($F_v$) for reflecting the amplification characteristics of Korean geological condition. In addition, the frequency distribution of depth to bedrock reported for Korean sites was also considered in calculating the site coefficients for H2 sites to incorporate sites having greater than 30 m of depth to bedrock. The relationships between the site coefficients and rock shaking intensity were proposed and then subsequently compared with the site coefficients of similar site classes suggested in other codes.

• International Commerce and Information Review
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• v.8 no.2
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• pp.59-78
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• 2006

Considering rapid development of Internet Portal Site Contents in Korea, it is an important issue to analyze consumers' satisfaction and e-loyalty. This research develops, and empirically test a model for explaining/predicting the satisfaction and e-loyalty with internet-based Electronic Trade Site. This paper describes a theoretical model for investigating the Satisfaction and e-Loyalty of the Electronic Trade Site. This study investigates the concept of the satisfaction, e-loyalty in Electronic Trade Site and its determinants, and tries to establish e-loyalty analyzing model. The model of the satisfaction, e-loyalty electronic trade site is tested here using data from 158 samples. Based on the research model, a comprehensive set of hypotheses is formulated and a methodology for testing them is outlined. some of the hypotheses are tested empirically to demonstrate the applicability of the theoretical model. In examining the relationships of the determinants factors, service quality satisfaction show in significantly by Reliability, Information Provided, Trustworthiness, Convenience, International of contents but that show in not significantly by Interaction. In addition, Electronic Trade site retention shows indirect effect between customer satisfaction and referral. Although our research can not show the determinants of e-loyalty in the electronic trade site the empirical result give both theoretical and managerial implication for managing the consumers' satisfaction and e-loyalty in electronic trade site.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.777-784
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• 2010

In the current Korean seismic design guide, the site classification and the corresponding site coefficients were determined based on the UBC-1997 (Uniform Building Code). In order to develop the current site classification system, it is important to compare the local site conditions in Korea to other countries which have similar seismic design guides. In the eastern United States, New York City(40degrees 45minutes north latitude, 73degrees 59minutes west longitude) suggested that current design guidelines are unsuitable to shallow bedrock depth sites. So the 3-parameter methods are performed for new criteria in New York City. In this study, site response analyses were performed at 181 study sites using one-dimensional equivalent linear to evaluate the site-specific earthquake ground motions at inland areas in the Korean peninsula and reclassify the results according to similar ground motions using the 3-parameter methods. It is effective that multi-parameter methods for Korean site characteristics in comparison with single parameter method.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.29 no.1
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• pp.93-103
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• 2019

Recently, malicious code distribution of ransomware through a web site based on a drive-by-download attack has resulted in service disruptions to the web site and damage to PC files for end users. Therefore, analyzing the characteristics of the target web site industry, distribution time, application type, and type of malicious code that is being exploited can predict and respond to the attacker's attack activities by analyzing the status and trend of malicious code sites. In this paper, we will examine the distribution of malicious codes to 3.43 million websites in Korea to draw out the characteristics of each detected landing site, exploit site, and distribution site, and discuss countermeasures.

• Journal of KIBIM
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• v.11 no.2
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• pp.24-32
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• 2021

Recently, starting with smart construction research, interest in technology that automates construction site management using artificial intelligence technology is increasing. In order to automate construction site management, it is necessary to recognize objects such as construction equipment or workers, and automatically analyze the relationship between them. For example, if the relationship between workers and construction equipment at a construction site can be known, various use cases of site management such as work productivity, equipment operation status monitoring, and safety management can be implemented. This study derives a real-time object detection platform architecture that is required when performing construction site management using deep learning technology, which has recently been increasingly used. To this end, deep learning models that support real-time object detection are investigated and analyzed. Based on this, a deep learning model development process required for real-time construction site object detection is defined. Based on the defined process, a prototype that learns and detects construction site objects is developed, and then platform development considerations and architecture are derived from the results.