• Journal of Korean Society of Disaster and Security
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• v.13 no.1
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• pp.1-11
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• 2020

One of the important problem in statistical hydrology is to estimate the appropriated probability distribution for a given sample data. For the problem, a goodness-of-fit test is conducted based on the similarity between estimated probability distribution and assumed theoretical probability distribution. Probability plot correlation coefficient test (PPCC) is one of the goodness-of-fit test method. PPCC has high rejection power and its application is simple. In this study, test statistics of PPCC were derived for generalized extreme value distribution (GEV) models based on L-moments and these statistics were suggested by the multiple and nonlinear regression equations for its usability. To review the rejection power of the newly proposed method in this study, Monte Carlo simulation was performed with other goodness-of-fit tests including the existing PPCC test. The results showed that PPCC-A test which is proposed in this study demonstrated better rejection power than other methods, including the existing PPCC test. It is expected that the new method will be helpful to estimate the appropriate probability distribution model.

• Korean Journal of Remote Sensing
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• v.37 no.5_1
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• pp.1207-1214
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• 2021

In thisletter, we developed technology which can exclude effect of cloudsto perform remote waterbody detection based on Sentinel-2 optical satellite imagery to calculate the area of ungauged reservoirs and applied to the Hwanggang dam reservoir, a representative ungauged reservoir, to verify usability. The remote waterbody detection technology calculates the cloud blocking ratio by comparing the cloud boundary in the Sentinel-2 imagery and the reservoir boundary first. Next, itselects data whose cloud blocking ratio does not exceed a specific value and calculates NDWI (Normalized Difference Water Index) with selected imagery. In last, it calculatesthe area of the reservoir by counting the number of grids which have NDWI value considered as waterbody within the boundary of the target reservoir and correcting with cloud blocking ratio. To determine cloud blocking ratio threshold forselecting image, we performed the area calculation of Hwanggang dam reservoir from July 2018 to October 2021. As a result, when the cloud blocking ratio threshold wasset 10%, we confirmed that the result with large error due to clouds were filtered well and obtained 114 results that can show changes in Hwanggang dam reservoir area among 220 images.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.529-536
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• 2021

In this study, nano-silica and nano-titanium were selected to determine the possibility of applying the binder to reactive nano materials. The basic characteristics of the nano material candidate group were reviewed. and the reactivity of nano materials was reviewed through K-value. The reactivity of the nano silicate materials was measured to be high. Therefore, as a final candidate group, nano silicate materials were selected. The finally selected reactive nano material was reviewed for its usability as a construction binder. The mechanical properties and unit weight of cement paste were reviewed using silica fume and blast furnace slag and nano materials. When cement composites with nano silicate materials, it was confirmed that it was effective in improving the mechanical performance and decrease the unit weight of cement composites.

• The Journal of the Korea Contents Association
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• v.19 no.6
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• pp.513-523
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• 2019

The purpose of this study is to develop and apply activity-based STEAM education programs to verify elementary school students' logical thinking skills, attitudes to STEAM, and changes in satisfaction. The activity-based STEAM education program was developed in a total of 3 rounds under the theme of 'Let's get through Ultraviolet rays.' The finally developed program, which was revised and supplemented by process of preliminary commitment to elementary school students, proved its effectiveness through statistical methods in 168 sixth-grade in S elementary school students in Gyeonggi-do. The results of the study are as follows: First, the activity-based STEAM education program was developed around the topic of "Let's get through Ultraviolet rays" based on the "The solar system and Star" unit of the 5th and 6th grades of elementary school science. Second, by applying the developed activity-based STEAM education program to elementary school students, their cognitive development level by science behavioral system was improved after class, and proportion of the logical thinking skills and logic of variable control represented a significant value(p<.05). Third, the attitudes toward STEAM education, consisting of seven sub-factors, presented significant statistical test results across other factors, except for communication and usability factors(p<.05). Fourth, in the satisfaction test, the average value of the lower section was 3.59 to 3.85 points, and overall it was positive.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.3
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• pp.237-254
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• 2019

This study is focused on the effect of sodium stearate, which is a hydrophilic gelling agent affecting on the hardness of O/W solid sunscreen cosmetic. The sunscreen of the O/W (oil in water) type is stable, good in use, and relatively easier to stabilize than the sunscreen of the W/O (water in oil) type. Methods for increasing the stability by using emulsifiers, electrolytes, and wax or oil have been studied for solid sunscreen. This study was intended to develop a solid sunscreen stabilized by increasing the hardness using sodium stearate as an O/W type containing more than 40% moisture. Response surface methodology (RSM) was used to analyze the factors affecting the hardness of cosmetics, and sodium stearate, polyol and oil were used for each factor. The hardness and the reaction value was measured using a rheometer. As a result, sodium stearate showed a meaningful value (p < 0.05) among the three factors affecting hardness. In addition, the use of sodium stearate as a hydrophilic gelling agent increased the usability and stability of the solid sunscreen.

• Management & Information Systems Review
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• v.38 no.1
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• pp.103-120
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• 2019

Recently, as mobile banking enables to instantly provide the customized service in accordance with customer demand via information technology. With this individual customized service, mobile banking plays a role of transforming the existing offline banking strategies. However, contrary to expectation, the mobile banking service has not been widely used to the extent that it can replace offline banking service. Therefore, the current study aims to explore the antecedents to affect customer's usage of mobile banking. Specifically, the antecedents influencing the intention to use and actual usage of mobile banking include personal-innovation fit, positive psychological capital, and service quality factors, which reflect the innovative technology characteristics of mobile banking. Furthermore, the paper also analyzes the effect of mobile banking service on intention to use and actual usage of mobile banking service. With empirical analysis using Structural Equation Modeling for 195 mobile banking users, the results showed that user's ability fit, value fit, and positive psychological capital positively affected user's future intention to use and actual usage of mobile banking. Furthermore, the current paper also found the significant moderation effect of usage purpose of mobile banking (banking task and online stock exchange) in the relationship between positive psychological capital and intention to use. This study suggests that banks need to develop mobile banking services that reflect customer's IT usability as well as their pursuing purpose and value.

• Journal of Korean Society of Archives and Records Management
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• v.21 no.3
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• pp.163-186
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• 2021

The purpose of this study is to analyze research trends on overseas business archives, compare them with domestic and related prior studies, and present the direction of the development of domestic business archives research. For the research analysis, bibliography from 493 papers was collected using four academic databases: Web of Science, Scopus, LISA (ProQuest), LISS (EBSCOhost). Following data collection, data analysis was conducted and focused on the publication status of related papers, major journals, research forms, and researcher information. In addition, unique words were extracted through the data processing of English abstracts, and the frequency of the key words was identified. Through topic modeling, this study extracted seven topics from the entire literature group, analyzed the publication trends of the papers corresponding to each topic, and examined the topics and representative papers of that topic. The names for these topics were assigned as "access and usability of business records'," "information/evidence value of business records," "importance and operational strategy of business archives," "record management as a business heritage," "management of business records in digital environments," "preservation and disposal of business records," and "historical value of business records." Based on the prior research and analysis results, this study proposed implications for the development and expansion of future research on the domestic business archives.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.1
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• pp.55-63
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• 2021

The roughness of the road is an important factor directly connected to the ride comfort, and is an evaluation item for functional evaluation and pavement quality management of the road. In this study, data on the road surface were acquired using the latest 3D geospatial information construction technology of ground LiDAR, drone photogrammetry, and drone LiDAR, and the accuracy and roughness of each method were analyzed. As a result of the accuracy evaluation, the average accuracy of terrestrial LiDAR were 0.039m, 0.042m, 0.039m RMSE in X, Y, Z direction, and drone photogrammetry and drone LiDAR represent 0.072~0.076m, 0.060~0.068m RMSE, respectively. In addition, for the roughness analysis, the longitudinal and lateral slopes of the target section were extracted from the 3D geospatial information constructed by each method, and the design values were compared. As a result of roughness analysis, the ground LiDAR showed the same slope as the design value, and the drone photogrammetry and drone LiDAR showed a slight difference from the design value. Research is needed to improve the accuracy of drone photogrammetry and drone LiDAR in measurement fields such as road roughness analysis. If the usability through improved accuracy can be presented in the future, the time required for acquisition can be greatly reduced by utilizing drone photogrammetry and drone LiDAR, so it will be possible to improve related work efficiency.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.3
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• pp.277-285
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• 2023

Recently, as the magnitude and frequency of earthquakes increases, research is needed to increase the ductility of the columns in order to prevent the collapse of structures. In this study, to evaluate the performance of columns reinforced with continuous transverse reinforcing bars, the FE model for the dynamic analysis of structures reinforced with continuous transverse reinforcing bars for circular and rectangular columns is to be verified using the results of uniaxial compression experiments in the previous study. As a result, the experimental value of the column reinforced with continuous transverse reinforcement and the result value related to the dynamic analysis showed similar behavior, and the reliability was high. As a result of the analysis, the usability of the rectangular column reinforced with continuous lateral reinforcing bars was confirmed because the dissipated energy performance of the columns reinforced with spiral reinforcing bars was higher than that of the columns reinforced with band reinforcing bars.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.3
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• pp.107-121
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• 2023

The assessment of perceived naturalness aims to elucidate the human perception and explain the interaction between natural environments and humans. The perception of ecological assets that exhibit distinct characteristics within a specific region can manifest in various representations. Based on the users' perceptions and interviews regarding ecological assets, this study assessed the perceived naturalness from a cultural services perspective. Specifically, the discussions on Ansan City's ecological assets and revolved around the inherent value of naturalness in dimensions, such as the necessity for conservation and the sustainable development of ecological assets, the perception of ecosystem benefits, the representativeness as a local asset, and usability. Subsequently, the Q method was employed to present 25 representative ecological assets to 25 users. As a result, user groups with different value systems for each question were identified, and hypothetical personas for cultural service enjoyment were distinguished. The most representative persona among the 25 users was identified as AWP (a type that values the conservation of aquatic ecosystems, prefers waterfront landscapes, and enjoys walking). Since perceived naturalness is conceptually similar to the "benefits perceived by users" in evaluating ecosystem services, it can provide more practical evaluation criteria for cultural services.