• Economic and Environmental Geology
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• v.51 no.6
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• pp.531-542
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• 2018

Batch sorption experiments were performed to remove the uranium (U) in groundwater by using the bamboo charcoal. For 2 kinds of commercialized bamboo charcoals in Korea, the U removal efficiency at various initial U concentrations in water were investigated and the optimal sorption conditions to apply the bamboo charcoal were determined by the batch experiments with replicate at different pH, temperature, and reaction time conditions. From results of adsorption batch experiments, the U removal efficiency of the bamboo charcoal ranged from 70 % to 97 % and the U removal efficiency for the genuine groundwater of which U concentration was 0.14 mg/L was 84 %. The high U removal efficiency of the bamboo charcoal maintained in a relatively wide range of temperatures ($10{\sim}20^{\circ}C$) and pHs (5 ~ 9), supporting that the usage of the bamboo charcoal is available for U contaminated groundwater without additional treatment process in field. Two typical sorption isotherms were plotted by using the experimental results and the bamboo charcoal for U complied with the Langmuir adsorption property. The maximum adsorption concentration ($q_m:mg/g$) of A type and C type bamboo charcoal in the Langmuir isotherm model were 200.0 mg/g and 16.9 mg/g, respectively. When 2 g of bamboo charcoal was added into 100 mL of U contaminated groundwater (0.04 ~ 10.8 mg/L of initial U concentration), the separation factor ($R_L$) and the surface coverage (${\theta}$) maintained lower than 1, suggesting that the U contaminated groundwater can be cleaned up with a small amount of the bamboo charcoal.

• The Journal of Engineering Geology
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• v.29 no.2
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• pp.99-112
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• 2019

Rainfall infiltration through the unsaturated zone is influenced by a range of factors including topography, geology, soil, rainfall intensity, temperature and vegetation; the actual infiltration varies largely in time and space. The infiltration capacity of soil is a critical factor in identifying groundwater recharge and leakage of surface water. It may differ depending on soil types and geological features of a particular basin or territory as well as on the usage of the land. This study was conducted in forest and farmland region of the mid-mountain area (EL. 50~300 m) of Jeju Island to test soil infiltration capacity of the area where rainfall contributes to groundwater. Results were analyzed using the four soil group classification methods presented by Jeong et al. (1995) and NAS (2007) to discover that the method offered by NAS (2007) is more reliable in the mid-mountain area of Jeju Island. The study compares and reviews the existing classification methods using the results of infiltration capacity tests executed on different soil groups throughout the whole region of the Jeju mid-mountain area. It is expected that this work will serve as a guideline for evaluating surface water recharge and hydraulic characteristics of Jeju Island.

• Management & Information Systems Review
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• v.38 no.3
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• pp.97-112
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• 2019

Currently, in China, mobile live broadcasts are more popular compared to online live broadcasts. Accordingly, this research focused on Wanghong, SNS's flagship live broadcasting app. In other words, Wanghong refers to an internet celebrity who acts online on social network services (SNS) influencing many other people. This study specifically focused on one social network service and conducted a study on live app users. The study first analyzed the quality factors of an SNS to users using China's live app. Secondly, the research investigated in finding out the impact of quality on the satisfaction of live app users and how this affects the live app user's satisfaction on their intention of continuous use. Studies have shown that information quality, system quality, and social quality among SNS quality have a positive influence on live app user satisfaction. However, the quality of service and the quality of emotion was rejected by the hypothesis. Throughout this study, we hope to create an app that allows users to share more satisfying mobile images, thereby establishing various episodes holding beautiful places of their life on a real-time basis. It is hoped that live broadcasting businesses will spread a significant impact around the world. Finally, in the future, research on the study of collective comparison between Korea and China on SNS is believed to be meaningful.

• Journal of Environmental Health Sciences
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• v.45 no.1
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• pp.71-81
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• 2019

Objectives: The lung injuries by exposure to the humidifier disinfectants (HDs) were reported in 2011, Korea. For the HD victims, environmental exposure level and clinical diagnosis were conducted to determine the levels of damage by HDs. Methods: The exposure assessment to the HDs from 1st to 4th questionnaire surveys were carried out for 5,245 victims. And the affecting factors of exposure levels were analyzed by characterizing exposure and demographic information. By using of exposure concentration and cumulative time, exposure levels were classified and compared by percentage of clinical diagnosis classes. The high exposure and low clinical diagnosis rating groups, and low exposure and high clinical diagnosis rating groups were analyzed to overcome the limitation of past exposure assessment such as recall bias. Results: Among the all applicants damaged by the humidifier disinfectants, survivors were 4,028 and the dead were 1,217. And male and female were 2,675, and 2,547, respectively. In case of occurrence age of lung disease, under 10 years was majority age group (1,536) and followed by thirties (917). Pregnant women and fetuses were 339 and 439, respectively. And the damages by exposure to the HDs were concentrated on these susceptible populations in groups with low exposure and high clinical diagnosis rating. On the other hand, the groups classified by high exposure and low clinical diagnosis rating were shown different characterization. Conclusions: The questionnaire survey on past exposure may be uncertain due to recall bias. However, the relationship between classified exposure levels and clinical diagnosis ratings might be shown positive correlation if the exposure assessment errors were analyzed and controlled.

• Korean Journal of Heritage: History & Science
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• v.54 no.3
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• pp.90-105
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• 2021

The shape of the roof is very important, as it determines the beauty of the exterior of Korean wooden architecture. In particular, the curve of the eaves is the most representative of the characteristics of Korean wooden architecture. Rafters and buyeon (浮椽), flying rafters, create curves for the eaves, and buyeon in particular makes the roof lighter and more dynamic. Although the function and role of buyeon are already known, nothing is yet clear about the beginning of its use in Korean ancient architecture. Accordingly, the purpose of this study is to determine when buyeon was first used in Korean architecture. To this end, I examined various records, buildings, remains, and artifacts that have architectural shapes in Korea, China, and Japan. The results are summarized as follows. First, the use of buyeon in China appears during the Northern Qi Dynasty (北齊) in the mid-6th century, but became common in the 7th century during the Tang (唐) Dynasty. Second, the use buyeon in Japan appears in the mid-8th century, when the capital was relocated from Asuka (飛鳥) to Nara (奈良). It corresponds with the time that Japan began importing Chinese culture directly. Third, the use of buyeon in Korea may have been introduced to Baekje from China in the mid-6th century, but it was not common. It is believed that it became common after active exchanges with the Tang Dynasty during the Unified Silla Period in the mid-7th century.

• Korean Journal of Heritage: History & Science
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• v.54 no.3
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• pp.192-203
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• 2021

This paper investigates the process of change in the meaning of the term gongye (工藝) (nowadays it means craft) during Korea's transition to the modern era. The Annals of the Joseon Dynasty (朝鮮王朝實錄) will serve as the basis for the examination of pre-modern usage, and the Korea-United States Treaty of 1882 for the changes that occurred between the translation from Chinese and from Japanese following the opening of the port . After the port opened, the meaning of gongye, which once broadly referred to the wide range of work of people from different fields, was narrowed down to singularly represent the manufacturing industry. Following the example of Japan, the first East Asian country to succeed in modernization, this new meaning of gongye was generally used in the context of embracing Western culture and creating industry. As industrialization emerged as a national mission, and new terminology was needed to express these new concepts, the Chinese characters used by the Japanese to translate Western concepts were directly imported and used without making any changes. Gongye was similar in meaning to gongeop (工業) (nowadays it means industry) at the time, and the two terms were used interchangeably. However, following the Japanese annexation of Korea, the cultural administration of the Governor-General imbued the term with artistic concepts, and gongye was differentiated from gongeop, As such, examining the establishment of terminology and concepts can be helpful for understanding the contradictions and problems of the Korean crafts scene, which were derived from a period in the past called the modern era.

• Journal of Environmental Impact Assessment
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• v.29 no.6
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• pp.403-413
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• 2020

A mathematical model comprised with eight simultaneous quasi-linear partial differential equations was suggested to provide optimal chlorination strategy. Upstream weighted finite element method was employed to construct multidimensional numerical code. The code was verified against measured concentrations in three type of reactors. Boundary conditions and reaction rate were calibrated for the sixteen cases of experimental results to regenerate the measured values. Eight reaction rate coefficients were estimated from the modeling result. The reaction rate coefficients were expressed in terms of pH and temperature. Automatic optimal algorithm was invented to estimate the reaction rate coefficients by minimizing the sum of squares of the numerical errors and combined with the model. In order to minimize the concentration of chlorine and pollutants at the final usage sites, a real-time predictive control system is imperative which can predict the water quality variables from the chlorine disinfection process at the water purification plant to the customer by means of a model and operate the disinfection process according to the influent water quality. This model can be used to build such a system in water treatment plants.

• Journal of Communication Design
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• v.59
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• pp.298-308
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• 2017

In the modern society in which globalization is ongoing in the overall culture social culture, various efforts are being made by each country around the world in order to search for the distinctive cultural identity and creativity. Recognizing the importance of the 'Korean' tradition, South Korea is also actively engaged in researches to develop design utilizing it and to apply it in real life. Here, developing Korean design does not simply refer to borrowing and imitating the traditional form or color but refers to generating a new, original and ethnic aesthetic consciousness that conform to the era that we are currently living in based on the unique ideology and sentiment inherent in its formativeness. Despite the fact that research on Korean traditional culture has continued for a long period of time, it is considered that such phenomenon continues to take place because the establishment and utilization of Korean culture identity is still insufficient. There, research on various fields based on new understanding with regards to our culture and the development of design utilizing it is in dire need. This study aims to analyze the said usage form and formative characteristics and the possibility of modern application focused on the lines and patterns which are most frequently mentioned when discussing about the Korean traditional formative beauty of Korea.

• Informatization Policy
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• v.28 no.2
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• pp.57-80
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• 2021

This study aimed to identify the causes of adult cyberbullying, an issue which arouses little academic interest despite its seriousness and its harmful consequences, in order to provide basic data for the formulation of reasonable measures for preventing and reducing adult cyberbullying. To that end, the author of the study analyzed the results of the government-led Cyber Violence Survey conducted in 2019. First, the online survey panel owned by the research company selected a sample of 1,500 adult men and women in their 20s to 50s in proportion to reflect the composition of the local population. The survey was conducted online, with male subjects and female subjects accounting for 51.5% and 48.7% of the respondents, respectively. The result of the analysis shows that the respondents' attitude towards cyberbullying was fully mediaed according to such factors as gender, age, family relations, relationship with colleagues, Internet usage time, and contact with illegal content. In addition, partial mediation was observed with regard to online delinquency colleague numbers and cyberbullying victimization. As a result, the respondents' attitude towards cyberbullying was found to be the most important factor affecting adult cyberbullying. Based on these results, this study suggests that the formation of a non-conservative attitude towards cyberbullying should be considered to be more important than any other factors when preparing programs aimed at preventing cyberbullying.

• Journal of Korean Library and Information Science Society
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• v.52 no.1
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• pp.155-178
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• 2021

In the era of the 4th industrial revolution, public libraries need a strategy for promoting intelligent library services in order to actively respond to changes in the external environment such as artificial intelligence. Therefore, in this study, based on the concept of artificial intelligence and analysis of domestic and foreign artificial intelligence related trends, policies, and cases, we proposed the future direction of introduction and development of artificial intelligence services in the library. Currently, the library operates a reference information service that automatically provides answers through the introduction of artificial intelligence technologies such as deep learning and natural language processing, and develops a big data-based AI book recommendation and automatic book inspection system to increase business utilization and provide customized services for users. Has been provided. In the field of companies and industries, regardless of domestic and overseas, we are developing and servicing technologies based on autonomous driving using artificial intelligence, personal customization, etc., and providing optimal results by self-learning information using deep learning. It is developed in the form of an equation. Accordingly, in the future, libraries will utilize artificial intelligence to recommend personalized books based on the user's usage records, recommend reading and culture programs, and introduce real-time delivery services through transport methods such as autonomous drones and cars in the case of book delivery service. Service development should be promoted.