• Journal of the Korean GEO-environmental Society
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• v.9 no.4
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• pp.77-84
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• 2008

Soil purification theory is the method using the soil micro-organism like aerobic and anaerobic for treatment of wastewater. The soil has many kinds of micro-organism and it multiply as change of the environment. Unlikely other methods, the soil purification theory is adaptable to inflow water change; moreover, it can process the T-N, T-P without any special method and management. The top is covered with the improved soil which can remove the bad smell and is used for resting place according to planting the lawn. This study is focused on analysis of the treatment processing of wastewater comparing inflow with outflow water. As a results, removal rate of the processing the BOD, COD and SS is almost 90~100% and it is 60~80% in T-N, T-P.

• Current Optics and Photonics
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• v.3 no.1
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• pp.46-53
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• 2019

Monte Carlo simulations were performed for a three-dimensional tissue model with and without an embedded large vessel, to understand how varying vessel geometry affects surface light distribution. Vessel radius was varied from 1 to 5 mm, and vessel depth from 2 to 10 mm. A larger difference in surface fluence rate was observed when the vessel's radius increased. For vessel depth, the largest difference was seen at a depth of approximately 4 mm, corresponding to human wrist region. When the vessel was placed at depths greater than 8 mm, very little difference was observed. We also tested the feasibility of using two source-detector pairs, comprising two detectors distinctly spaced from a common source, to noninvasively measure blood-scattering changes in a large vessel. High sensitivity to blood-scattering changes was achieved by placing the near detector closer to the source and moving the far detector away from the source. However, at longer distances, increasing noise levels limited the sensitivity of the two-detector approach. Our results indicate that the approach using two source-detector pairs may have potential for quantitative measurement of scattering changes in the blood while targeting large vessels near the human wrist region.

• Health Policy and Management
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• v.32 no.4
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• pp.356-367
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• 2022

Background: The emergence of new infectious diseases threatens public health, increasing socioeconomic damage, and national risks. This study aimed to develop an evidence-based risk assessment tool to quickly respond to new infectious diseases. Methods: The risk elements were extracted by reviewing the risk assessment methods of the World Health Organization, United States, Europe, United Kingdom, and Germany, and the validity and priority of elements were determined through expert meetings and Delphi surveys. Then, the scale and level for each risk element were defined and a final score calculation method according to the risk evaluation result was derived. The developed risk assessment tool was verified using data at the time of domestic transmission of an emerging infectious disease. Results: In case of spread of actual infectious diseases, priority is determined based on the criticality of the elements in each area of transmissibility and severity, from which the weighted score of the risk assessment is derived. Then, the risk score for each element was calculated by multiplying the average value of the risk evaluation by its weight and the evaluation risk assessment score for the two areas was calculated. At last, the final score is plotted in a matrix where the x-axis indicates the transmissibility and the y-axis the severity and plotted on the coordinate plane for time series use. Conclusion: With respect to transmissibility and severity, this risk assessment method to respond to new and re-emerging infectious diseases enables rapid and evidence-based evaluation by quantitatively and qualitatively assessing various risk elements.

• The Journal of the Acoustical Society of Korea
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• v.43 no.3
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• pp.324-334
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• 2024

The Wavefront Curvature Ranging (WCR) is an estimation method for a source range from the wavefront curvature of acoustic waves. The conventional method uses trigonometry to estimate the source range by assuming the sound speed as a constant. Because of this assumption, range error occurs in the ocean environment where the bottom reflection is clearly separated. In order to reduce the range error, Matched Wavefront Curvature Ranging (MWCR) was proposed applying the sound speed structure in the ocean environment and Maximum Likelihood Estimation (MLE). The range error was reduced in the results of the simulation on the proposed method. In the future, this method will be applicable to the sonar system if the reliability of ranging is confirmed by measured signal.

• The Journal of the Acoustical Society of Korea
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• v.43 no.4
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• pp.437-444
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• 2024

Bistatic sonar performance varies significantly depending on the ocean environment, the location (latitude, longitude) and water depth of the source and receiver. Therefore, research on optimal deployment of bistatic sonar considering ocean environment is necessary. In this study, we suggest an algorithm to optimize the location and water depth of source and receiver when operating monostatic and bistatic sonar on two spatially separated surface ships in the Ulleung Basin in the East Sea. A particle swarm optimization algorithm was used to search the location and water depth of the source and receiver to maximize the detectable area within the search area. As a result of performing bistatic sonar deployment using the algorithm proposed in this study, the detectable area increased as the number of model iterations increased. Additionally, it was confirmed that the source and receiver on the two surface ships converged to the optimal location and water depth.

• Journal of Life Science
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• v.24 no.5
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• pp.543-548
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• 2014

Aquifer recharge and recovery is a technology used to ensure a stable supply of clean water. During the process, river water is injected into a soil aquifer and stored. The stored water is then recovered and used to produce drinking water. It is important to understand quality improvement of the injected water while it is stored in the aquifer. In the present study, a lab-scale column reactor containing saturated-zone soil was employed to mimic an aquifer. The reactor was used to investigate microbial removal of nitrate that is a major inorganic contaminant detected in the Nakdong River. The reactor was introduced with river water that contained nitrate at concentrations (5.07, 6.81, 8.27, and 11.07 mg $NO_3{^-}/l$) detected downstream of the Nakdong River in the past 2 years. The nitrate concentrations decreased during the introduced water is retained in the reactor. Effluent from the reactor contained 1.49 mg $NO_3{^-}/l$ or less and had an average pH of 7.98 regardless of the nitrate concentrations of the influent. However abiotic control reactor showed similar nitrate-concentrations in its influent and effluent. Considering the result of abiotic control, the decreased nitrate concentration observed in the test column suggested that microorganisms in saturated-zone soil removed nitrate in the river water introduced into the reactor. Results of this study will be used to better understand microbial improvement of water quality in aquifer recharge and recovery technology.

• Journal of The Korean Association For Science Education
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• v.33 no.4
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• pp.763-777
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• 2013

This is a case study on two schools practising integrated science education (hereafter ISE). The purposes of this study are to investigate the types and features of ISE in the schools actively practising ISE, to identify the contextual factors of the schools, and to give implications for implementing ISE in schools. This study investigated the contextual factors in practicing ISE with a focus on the two schools, a middle school in Gyeonggi-do and a high school in Busan. They were breaking down the boundaries among teaching subjects and providing student-oriented instruction with problems in the real world. The data were collected by observing classes, by interviewing teachers, and by reviewing school documents and students' reports. The research findings are as follows: first, the two schools took part in ISE actively. They teach science to students providing integrated experiences mainly by using interdisciplinary knowledge and/or by solving the problems pertaining to the real world. While the former integrated subjects centering on topics, the latter focused on a project-based learning driven by students. They have differences in regard to the role of teachers and students, the level of integration and the type of integration. Second, the contextual factors that enabled ISE to be implemented there were found. The previous studies revealed six contextual factors in practising ISE: small and stable learning environment, leadership, team activities, in-school planning time, flexible timetable and community links. This study also found similar factors. However, the cases of this study provided ISE on a large scale and in a short period of time, instead of a small and stable learning environment. Teachers viewed the process of ISE not only as a tool to overcome the conservative culture of teachers but also as a pursuit of innovation.

• The Journal of the Acoustical Society of Korea
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• v.37 no.1
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• pp.31-38
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• 2018

Based on the measured data in the south western sea of Jeju Island during the SAVEX15(Shallow Water Acoustic Variability EXperiment 2015), the effect of internal waves on the PPD (Predictive Probability of Detection) of a sonar system was analyzed. The southern west sea of Jeju Island has complex flows due to internal waves and USC (Underwater Sound Channel). In this paper, sonar performance is predicted by probabilistic approach. The LFM (Linear Frequency Modulation) and MLS (Maximum Length Sequence) signals of 11 kHz - 31 kHz band of SAVEX15 data were processed to calculate the TL (Transmission Loss) and NL (Noise Level) at a distance of approximately 2.8 km from the source and the receiver. The PDF (Probability Density Function) of TL and NL is convoluted to obtain the PDF of the SE (Signal Excess) and the PPD according to the depth of the source and receiver is calculated. Analysis of the changes in the PPD over time when there are internal waves such as soliton packet and internal tide has confirmed that the PPD value is affected by different aspects.

• (The)Study of the Eastern Classic
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• no.41
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• pp.385-406
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• 2010

Lee Byeong-hun was introduced to Hanjuhak when he was taught by Myeonwoo Gwak Jong-seok. It is assumed that Hanjuhak circles had a certain influence on formation of his ideas in that they had liberal tendency at that time. Lee Byeong-hun accepted Geummungyonghak developed by Gang Yu-wee of China and participated in Confucian Science Movement while excluding Confucianism. After he accepted western civilization and the ideas of Gang Yu-wee, no traces of Hanjuhak was found in his writing, but it is assumed that Hanjuhak might work as a nutritious element for his ideas. He thought that religious nature of Confucianism could be revived only when he left Neo-confucianism which changed Confucianism into a philosophy by insisting reason instead of God. So, he respected Confucius as a religious founder and left such concepts as reason and respect which were considered important in Neo-confucianism and valued disposition and faith in "Jungyong", a doctrine of the Mean. He considered Confucianism as religious and joined in religious practices such as praying and reciting scriptures. He insisted that filial piety indicates a filial son of the Heaven when interpreting the following passage: Shun (Chinese leader) is a filial duty, which is assumed that he was influenced by Christianity. He respected Confucius as the only religious founder and God as the God to make Confucianism a religion. It is believed that he considered only Confucius as a founder instead of traditional Confucian sages as religion such as Buddhism and Christianity has one founder. God he thought is related with the God in Christianity and furthermore accepted reincarnation of Buddhism which is contrary to Confucian ideas. According to "Gyeongseol" by Lee Byeong-hun, it was believed that he was engaged in religion based on a faith that Confucianism is a religion rather than he pursued Confucianism as a religion to find out a way of its survival.

• The Journal of Korean Philosophical History
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• no.59
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• pp.371-393
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• 2018

Jeong Yak-yong attempted to establish a new philosophical system through the criticism on Neo-Confucianism. The most important area among the ideas of Dasan is on the ethical thoughts. He has a tremendous interest in the ethical education as well as ethical thought. During his exile, he gathered children around and educated them by editing "Jegyeong(弟經)". Dasan regarded "Sohak(小學)" to have some problems in educating children. Thus, he reconstructed the contents of "Sohak" and edited "Jegyeong". "Jegyeong" is more concise than Sohak and is a textbook focusing on children which is mainly composed of practical etiquette in the everyday life. It contains etiquettes to parents, teachers and adults, etiquettes on food in the everyday life and etiquettes between men and women. Although the contents does not exceed the scope of Sohak, he selected reasonable contents and composed with practical contents. Thus, it is practical. Dasan also attempted to make a novel interpretation on Saseo (四書), i.e., Noneo, Maengja, Daehak and Jungyong. His new interpretation on Saseo can be considered as ethical textbooks in a broad sense. Dasan considered the key ethical principle of Saseo (四書) to be Seo (恕). Accordingly, he thought it is very important to understand and practice ethical principle of Seo (恕). Dasan studied and annotated "Simgyeong(心經)" and "Sohak(小學)" for self moral discipline. And, he thought it is utmost important to understand and accept the existence of Sangje (上帝) in order to keep moral mind. He believed it to be important to have Gyesingonggu (戒愼恐懼), which is to aware and respect the existence of Sangje (god) for self discipline and Sindok (愼獨) to be cautious about things that only he was aware of. He thought that if people are aware of Sangje (上帝) and make dialog with Sangje, the will of Sangje could be expressed into Dosim (道心). In the ethical education, it can be said that, ultimately, the awareness on the absolute being is the most important point to Dasan.