• Journal of Korea Water Resources Association
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• v.56 no.8
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• pp.497-508
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• 2023

Agricultural reservoirs are crucial structures for water resources monitoring especially in Korea where the resources are seasonally unevenly distributed. Optical and Synthetic Aperture Radar (SAR) satellites, being utilized as tools for monitoring the reservoirs, have unique limitations in that optical sensors are sensitive to weather conditions and SAR sensors are sensitive to noises and multiple scattering over dense vegetations. In this study, we tried to improve water body detection accuracy through optical-SAR data fusion, and quantitatively analyze the complementary effects. We first detected water bodies at Edong, Cheontae reservoir using the Compact Advanced Satellite 500(CAS500), Kompsat-3/3A, and Sentinel-2 derived Normalized Difference Water Index (NDWI), and SAR backscattering coefficient from Sentinel-1 by K-means clustering technique. After that, the improvements in accuracies were analyzed by applying K-means clustering to the 2-D grid space consists of NDWI and SAR. Kompsat-3/3A was found to have the best accuracy (0.98 at both reservoirs), followed by Sentinel-2(0.83 at Edong, 0.97 at Cheontae), Sentinel-1(both 0.93), and CAS500(0.69, 0.78). By applying K-means clustering to the 2-D space at Cheontae reservoir, accuracy of CAS500 was improved around 22%(resulting accuracy: 0.95) with improve in precision (85%) and degradation in recall (14%). Precision of Kompsat-3A (Sentinel-2) was improved 3%(5%), and recall was degraded 4%(7%). More precise water resources monitoring is expected to be possible with developments of high-resolution SAR satellites including CAS500-5, developments of image fusion and water body detection techniques.

• Journal of Internet Computing and Services
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• v.24 no.6
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• pp.31-39
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• 2023

The purpose of this study is to propose a scientific performance evaluation framework for measuring and managing the overall outcome of complex types of projects that are linked to public demand-based commercialization, such as information system projects and public procurement, in integrated national R&D projects. In the case of integrated national R&D projects that involve multiple research institutes to form a single final product, and in the case of demand-based demonstration and commercialization of the project results, the existing evaluation system that evaluates performance based on the short-term outputs of the detailed tasks comprising the R&D project has limitations in evaluating the mid- and long-term effects and practicality of the integrated research products. (Moreover, as the paradigm of national R&D projects is changing to a mission-oriented one that emphasizes efficiency, there is a need to change the performance evaluation of national R&D projects to focus on the effectiveness and practicality of the results.) In this study, we propose a performance evaluation framework from a structural perspective to evaluate the completeness of each national R&D project from a practical perspective, such as its effectiveness, beyond simple short-term output, by utilizing the Hourglass model. In particular, it presents an integrated performance evaluation framework that links the top-down and bottom-up approaches leading to Tool-System-Service-Effect according to the structure of R&D projects. By applying the proposed detailed evaluation indicators and performance evaluation frame to actual national R&D projects, the validity of the indicators and the effectiveness of the proposed performance evaluation frame were verified, and these results are expected to provide academic, policy, and industrial implications for the performance evaluation system of national R&D projects that emphasize efficiency in the future.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1353-1369
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• 2023

In the event of a disaster accident at sea, the scale of damage will vary due to weather effects such as wind, currents, and tidal waves, and it is obligatory to minimize the scale of damage by establishing appropriate control plans through quick on-site identification. In particular, it is difficult to identify pollutants that exist in a thin film at sea surface due to their relatively low viscosity and surface tension among pollutants discharged into the sea. Therefore, this study aims to develop an algorithm to detect suspended pollutants on the sea surface in RGB images using imaging equipment that can be easily used in the field, and to evaluate the performance of the algorithm using input data obtained from actual waters. The developed algorithm uses image enhancement techniques to improve the contrast between the intensity values of pollutants and general sea surfaces, and through histogram analysis, the background threshold is found,suspended solids other than pollutants are removed, and finally pollutants are classified. In this study, a real sea test using substitute materials was performed to evaluate the performance of the developed algorithm, and most of the suspended marine pollutants were detected, but the false detection area occurred in places with strong waves. However, the detection results are about three times better than the detection method using a single threshold in the existing algorithm. Through the results of this R&D, it is expected to be useful for on-site control response activities by detecting suspended marine pollutants that were difficult to identify with the naked eye at existing sites.

• Journal of Venture Innovation
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• v.4 no.1
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• pp.1-21
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• 2021

Recently, as the number of foreigners residing in Korea has increased, Korea is preparing to enter a multicultural country. This study was conducted to present a social integration model for the purpose of solving the social problem of social integration of multicultural families. The purpose of this study is as follows. First, this study examines the role of local social capital for social integration by improving the quality of life of multicultural families and increasing their intention to participate in society. Second, the purpose of this study is to examine the effects of multicultural family members on the formation of local social capital, subjective quality of life and social participation intention, focusing on the role of social enterprises. To achieve the purpose of this study, members of multicultural families living in Seoul and Gyeonggi Province were selected as samples, and responses to local social capital, subjective quality of life, social participation intention and social identity were collected through structured questionnaires. A total of 363 valid questionnaires were tested for the relationship between variables through the structural equation model. The analysis result of this study is that first, human social capital and corporate social capital of members of multicultural families have a significant positive effect on subjective quality of life. Second, it was found that the corporate social capital and community social capital of members of multicultural families had a significant positive effect on the intention to participate in society. Third, it was found that the subjective quality of life of members of multicultural families did not significantly affect their intention to participate in society. Finally, it was found that social identity plays a partly controlling role when community capital of multicultural family members affects their intention to participate in society. Through this analysis result, it is expected that it will play a meaningful role as basic data for policy proposals for social integration of multicultural families.

• Land and Housing Review
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• v.14 no.4
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• pp.77-93
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• 2023

The COVID-19 pandemic has brought about significant social changes through government prevention and control measures, changes in people's risk perceptions, and lifestyle changes. In response, urban inhabitants changed their behaviors significantly, including their preferences for transportation modes and urban spaces in response to government quarantine policies and concerns over the potential risk of infection in urban spaces. These changes may have long-lasting effects on urban spaces beyond the COVID-19 pandemic or they may evolve and develop new forms. Therefore, this study aims to explore the potential for urban spaces to adapt to the present and future pandemics by examining changes in urban residents' preferences in travel modes and urban space use due to the COVID-19 pandemic. This study found that overall preferences for travel modes and urban spaces significantly differ between the pre-pandemic, pandemic, and post-pandemic periods. During the pandemic, preferences for travel modes and urban spaces has decreased, except for privately owned vehicles and green spaces, which are perceived to be safe from transmission, show more favorable than others. Post-pandemic preferences for travel modes and urban spaces are less favorable than pre-pandemic with urban spaces being five times less favorable than transportation. Although green spaces and medical facilities that were positively perceived during the pandemic are expected to return to the pre-pandemic preference level, other factors of urban spaces are facing a new-normal. The findings suggest that the COVID-19 pandemic has had a significant impact on urban residents' preferences for travel modes and urban space use. Understanding these changes is crucial for developing strategies to adapt to present and future pandemics and improve urban resilience.

• The Journal of Korean Academy of Sensory Integration
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• v.21 no.2
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• pp.69-83
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• 2023

Objective : This study sought to systematically examine the intervention effect of social stories when applied in relation to children with sleep disorders. Methods : Studies available in the SCOPUS, ScienceDirect, PsycArticles, and PubMed databases that were published from 2001 to 2022 were searched. The keywords used for the search were as follows: ("social story" OR "social stories") AND ("sleep" OR "sleep disorders" OR "sleep wake disorder bedtimes" OR "sleep initiation and maintenance disorders" OR "sleep wake disorder" OR "sleep arousal disorders"). Based on the selection criteria, six experimental studies were selected and analyzed. Results : The selected studies were two randomized controlled trials, three individual trials, and one case study. The subjects were mostly children diagnosed with autism spectrum disorder who were school-aged or adolescent. The intervention types were often complex interventions, including social stories and other interventions, while the durations of the interventions varied from one day to more than 40 days. The interventions had a positive effect on the subjects' sleep quality, with night wakings, sleep onset delay, and sleep anxiety all being improved. As standardized assessment tools to evaluate the effectiveness of social stories, the Child Sleep Habits Questionnaire and the Child Behavior Checklist were used in two papers each, and were the most commonly used. As non-standardized assessment tools, each of the four papers used turbulence and sleep diaries as assessment tools. Conclusion : The effect of social story mediation can be divided into sleep quality and sleep-related behavior. In terms of sleep quality, studies showing improvements in night wakings, sleep onset delay, and sleep anxiety accounted for a large proportion of the sample. The detailed effect area of sleep quality showed a significant improvement after the interventions in most studies, and in all six studies analyzed in the present study, the continuation of the effect after the intervention was confirmed via follow-up tests. Thus, the findings of this study are expected to be helpful when applying social stories in children with sleep disorders in clinical practice due to presenting the intervention effects, outcome evaluation tools, and intervention periods in children with sleep disorders in prior investigations involving social stories.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.3
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• pp.191-209
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• 2023

Amid rapid changes in technological innovation due to the influence of the 4th Industrial Revolution and COVID-19, research related to absorption capacity and patent activities to promote technological innovation of Korean technology start-ups is important in this uncertain environment. This study aims to examine the effects on entrepreneurial performance and patent activities by reconstructing absorptive capacity, an organizational capability, for technology-based startups in fields such as BT and ICT with less than seven years of establishment, distinguishing between potential absorptive capacity and realized absorptive capacity. The study also seeks to develop a theoretical research model. To accomplish this, data was collected from managerial executives, including CEOs of 215 technology startups. The following hypotheses were tested: Firstly, potential absorptive capacity had a significant impact on patent activities, while realized absorptive capacity did not. Secondly, potential absorptive capacity had a significant impact on technological performance, while realized absorptive capacity did not. Thirdly, both potential and realized absorptive capacity had a significant impact on financial and non-financial performance. Fourthly, patent activities indirectly influenced potential absorptive capacity and technological performance, but did not affect realized absorptive capacity. Fifthly, patent activities indirectly influenced potential absorptive capacity and financial performance, but did not affect realized absorptive capacity. Lastly, patent activities indirectly influenced potential absorptive capacity and non-financial performance, but did not affect realized absorptive capacity. The practical significance of this study lies in providing useful guidelines for building the core capabilities of organizations through absorptive capacity and patent activities. Furthermore, it is expected that startups that have not recognized the formation process of absorptive capacity for patent activities will perceive the formation mechanism of absorptive capability anew and show considerable interest in future potential and realized absorptive capacity as part of their management strategies. This is anticipated to play an important role in adapting to rapidly changing technological advancements, the startup ecosystem, and securing sustainable competitive advantages.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.5
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• pp.205-221
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• 2022

In this study, the authors investigated the effect of salesperson's Selling Influence Tactics (SIT) on customers' psychological obligation, trust in salespersons and repurchase intentions in the offline cosmetics purchase channel. In addition, we examined the moderating effect of service quality perceived by customers. To this end, a survey was conducted on 298 customers who had purchased cosmetics through the offline sales channel, and the authors conducted hypothesis testing through a structural equation model. As a result of the study, first, among salesperson's sales influence tactics, emotional appeal tactics (H1a), customer ingratiation tactics (H1d), and personal appeal tactics (H1e) were found to affect the psychological obligation of customers, and emotional appeal tactics (H2a), rational persuasion tactics (H2b), information provision tactics (H2c), and customer ingratiation tactics (H2d) were found to affect trust in salespeople. Third, it was found that the psychological obligation did not have a positive (+) effect on the customer's repurchase intention, and the customer's trust in the salesperson had a positive (+) effect on the repurchase intention. Third, perceived service quality showed a significant moderating effect between psychological obligation and repurchase intention, trust in salesperson and repurchase intention. In previous studies on salesperson's Selling Influence Tactics (SIT), many studies examined salesperson's Selling Influence Tactics (SIT) by specifying sub-variables in a limited way, and studies confirming marketing factors such as repurchase intention were also insufficient. Therefore, the results of the empirical research confirmed based on this study are expected to help the standard or direction of the salesperson's Selling Influence Tactics (SIT) in future studies. In addition, this study describes implications for providing help in employee education and management for small business owners who manage and operate offline cosmetics stores, and sales strategies that should be strategically established to improve perceived service quality for customers.

• Journal of the Korean Applied Science and Technology
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• v.41 no.2
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• pp.508-519
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• 2024

In this study, in order to evaluate the possibility of using Jubak as a functional cosmetic material, evaluation of antioxidant activity according to fractions and anti-wrinkle efficacy in CCD-986sk cells, a human fibroblast, were conducted. As a result of confirming the antioxidant activity by measuring ABTS⁺ radical scavenging ability, Jubak's Ethyl Acetate fractions was found to be 75.5% at a concentration of 1,000 ㎍/ml, showing the highest antioxidant activity among the extraction solvents. The wrinkle improvement effect was confirmed by measuring the inhibitory activity of elastase and collagenase, and in both test results, Jubak's Ethyl Acetate fractions showed the highest efficacy at a concentration of 1,000 ㎍/ml. As a result of measuring the synthesis rate of pro-collagen type I in CCD-986sk cells induced by UVB, Jubak showed the highest efficacy in the order of Ethyl Acetate, Water, Acetonitrile, and Hexan fractions at the same concentration of 20 ㎍/ml. As a result of measuring the inhibition rate of MMP-1, a collagen degrading enzyme, all four solvent fractions showed an efficacy of more than 70% at 20 ㎍/ml. As a result of measuring the mRNA expression levels of pro-collagen type I, MMP-1, and MMP-3 in a real-time PCR experiment, the protein expression level of pro-collagen type I increased when treated with Jubak fractions compared to the UVB group alone. The mRNA expression levels of MMP-1 and MMP-3 were confirmed to be decreased, and Ethyl Acetate fractions was the most effective in improving wrinkles after the control group (EGCG). As a result, it was confirmed that the Ethyl Acetate fractions among Jubak's solvent fractions has an anti-wrinkle effect against photoaging caused by UVB stimulation, and is expected to be used as a natural material for cosmetics.

• Journal of Korean Society of Disaster and Security
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• v.16 no.4
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• pp.45-59
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• 2023

The global focus on mitigating climate change has traditionally centered on carbon dioxide, but recent attention has shifted towards methane as a crucial factor in climate change adaptation. Natural settings, particularly aquatic environments such as wetlands, reservoirs, and lakes, play a significant role as sources of greenhouse gases. The accumulation of organic contaminants on the lake and reservoir beds can lead to the microbial decomposition of sedimentary material, generating greenhouse gases, notably methane, under anaerobic conditions. The escalation of methane emissions in freshwater is attributed to the growing impact of non-point sources, alterations in water bodies for diverse purposes, and the introduction of structures such as river crossings that disrupt natural flow patterns. Furthermore, the effects of climate change, including rising water temperatures and ensuing hydrological and water quality challenges, contribute to an acceleration in methane emissions into the atmosphere. Methane emissions occur through various pathways, with ebullition fluxes-where methane bubbles are formed and released from bed sediments-recognized as a major mechanism. This study employs Biochemical Methane Potential (BMP) tests to analyze and quantify the factors influencing methane gas emissions. Methane production rates are measured under diverse conditions, including temperature, substrate type (glucose), shear velocity, and sediment properties. Additionally, numerical simulations are conducted to analyze the relationship between fluid shear stress on the sand bed and methane ebullition rates. The findings reveal that biochemical factors significantly influence methane production, whereas shear velocity primarily affects methane ebullition. Sediment properties are identified as influential factors impacting both methane production and ebullition. Overall, this study establishes empirical relationships between bubble dynamics, the Weber number, and methane emissions, presenting a formula to estimate methane ebullition flux. Future research, incorporating specific conditions such as water depth, effective shear stress beneath the sediment's tensile strength, and organic matter, is expected to contribute to the development of biogeochemical and hydro-environmental impact assessment methods suitable for in-situ applications.