• Journal of the Korean GEO-environmental Society
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• v.24 no.9
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• pp.25-32
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• 2023

The Korean Industrial Standards (KS F) have a various regulations for measuring the weight of dried soil and rock. However, if the dried weight is measured in air after drying at 110±5℃ or 105±5℃, a weight singularity occurs, in which the weight decreases and then increases as the measurement time continues. In this study, basaltic rock from Ulleung Island was oven dried at 40 to 110℃. The weight was measured on an electronic scale with a sensitivity of 0.0001g (0.1mg) to find weight singularities. A method to easily determine the dry weight using the weight singularities was presented. As a result of analyses of the singularity of rock specimen according to temperature, the singularities were appeared in the temperature range of 40 to 110℃, and the weight of the singularity was smaller as the heating temperature increased. In particular, the weight singularity duration appeared, and the duration of the singularity was shorter as the heating temperature increased. The results of the convection measurement experiment showed that the cause of the singularity is the convection phenomenon caused by the contact of the heated rock with the air. The weight decrease of oven dried rock occurs when the effect of convection is dominant over the effect of air moisture absorption. Conversely, the weight increase of rock occurs when the effect of air moisture absorption is dominant over the effect of convection.

• Journal of Acupuncture Research
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• v.40 no.3
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• pp.245-251
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• 2023

Background: The incidence of facial palsy has been increasing. Many patients consult both Korean and Western physicians; however, no critical pathway (CP) for facial palsy has been established based on integrated medicine including Korean medicine, Western medicine, and complementary and alternative medicine. Thus, we developed and implemented an integrated CP for patients with acute facial palsy and investigated the satisfaction with CP. Methods: Overall, 20 patients who received treatment following the CP and 20 medical staff members involved in their care responded to a questionnaire survey. The questionnaire was developed based on a review of previous studies and focused on the satisfaction with the CP. Results: Patients' satisfaction score with the integrated CP was ≥ 4.4 for all items using a 5-point Likert-type scale. Smooth and cooperative treatment procedures, time-saving practices, and a clear explanation of the integrated treatment plan were satisfactory factors. Additionally, they preferred incorporating specialized facial massage and receiving education on self-exercise or massage techniques as complementary therapies. The medical staff members expressed a high level of satisfaction with the CP; however, the work division and treatment guidelines must be improved. Conclusion: An integrated CP program for acute facial palsy was implemented, and the satisfaction levels of patients and medical staff members were assessed. The results revealed high levels of satisfaction, and several improvements identified will be incorporated into clinical practice going forward.

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.2
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• pp.42-54
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• 2023

The population is concentrated in the metropolitan areas in Korea, and low-density residential areas are transforming into high density residential areas through redevelopment to meet this demand. However, large-scale redevelopment in a short period of time has a negative impact on the urban climate, such as generating a heat island effect due to the reduction of urban green areas. In this study, the change in surface temperature from 2013 to 2022 in the redevelpment areas of Godeok-dong and Dunchon-dong, Gangdong-gu, Seoul, was analyzed using Landsat 8 satellite images. In the Godeok-dong area, the difference in surface temperature was analyzed for the target redevelopment area, forest area, mixed forest and urban area, and low density residential area. In the Dunchon-dong area, the difference in surface temperature was analyzed for the target redevelopment area, forest area, and low density residential area. The difference in surface temperature was analyzed through multiple regression analysis conducted yearly over the three different stages in redevelopment period. The results from the multiple regression analysis show that in both areas, the land surface temperature of target redevelopment area was higher than that of the forest area and lower than low density residential area. It can be seen that these results occurred because the low-density residential area in Godeok-dong and Dunchon-dong had a lower green area ratio and a higher building-to-land ratio than the target redevelopment area. The results of this study suggest that even if low-density residential areas are transforming into high-density areas, adjusting the management of green areas and building-to-land ratio can contribute to lessen urban heat island effect.

• Journal of Korea Water Resources Association
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• v.56 no.9
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• pp.529-541
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• 2023

Due to the growing concern over forecasting extreme weather events such as droughts caused by climate change, there has been a rising interest in seasonal meteorological forecasts that offer ensemble predictions for the upcoming seven months. Nonetheless, limited research has been conducted in South Korea, particularly in assessing their effectiveness at the catchment-scale. In this study, we assessed the accuracy of ECMWF's seasonal forecasts (including precipitation, temperature, and evapotranspiration) for the period of 2011 to 2020. We focused on 12 multi-purpose reservoir catchments and compared the forecasts to climatology data. Continuous Ranked Probability Skill Score method is adopted to assess the forecast skill, and the linear scaling method was applied to evaluate its impact. The results showed that while the seasonal meteorological forecasts have similar skill to climatology for one month ahead, the skill decreased significantly as the forecast lead time increased. Compared to the climatology, better results were obtained in the Wet season than the Dry season. In particular, during the Wet seasons of the dry years (2015, 2017), the seasonal meteorological forecasts showed the highest skill for all lead times.

• Journal of Korean Dental Hygiene Science
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• v.5 no.2
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• pp.97-104
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• 2022

Background: Due to the declining number of students preparing for university entrance exams , the quota of universities has been decreasing continuously. This situation became increasingly diverse as new media used online, mobile, and PR tools to continuously invite students. This study is aimed at offering the helpful data to plan an effective PR strategy by analyzing the correlation between the major selection and satisfaction of the department's social media usage among freshmen majoring in dental hygiene. Methods: The collected data from the self-reported survey with freshmen were analyzed using the SPSS 22.0 program. The survey items were motive to select the major, social media platform that subjects used, reasons to use the media, time to visit the department's social media platform, and satisfaction level on the department's social media platform, using a 5-point Likert Scale. Results: The reasons for choosing a major were given by 32.2% and 15.9% respondents, respectively, as the vision after graduation and practice facilities. 39.9% and 31.4% used Instagram and YouTube for social media platforms, respectively, for using social media platform; 26.9% and 26.3% visited the department's social media before and after entering the university, respectively; 46.4% and 24.9% used Instagram and YouTube for department social media; and they generally satisfied with the contents of the department's social media. 40.9% of them said that information from the department's social media was useful. 33.8% of them said the information from the department's social media exceeded their expectations. 46.8% of them answered that the department's social media made the department's image positive. 33.4% got interested in the major more due to the department's social media. According to 32.1% of respondents, the department's social media was helpful in deciding on a major. With 35.4%, a positive correlation was discovered between the department's practice facilities and satisfaction on the department's social media. Conclusion: It is thought that the department's social media should try continuously by uploading the contents to meet the users' needs on a regular basis and seeking the plans to be able to collect various opinions using surveys through the related social media so that students can select the major and, moreover, lead the positive direction to adapt the university life under the unfamiliar environment after admission.

• Journal of Environmental Impact Assessment
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• v.32 no.4
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• pp.230-241
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• 2023

At a time when it is urgent to establish a management system for landscape quality assessment of offshore wind farms in Korea, we analyzed foreign cases to draw implications for improving the landscape quality assessment of offshore wind farms in Korea and to explore the direction of efficient landscape assessment. The main contents derived from the analysis of overseas cases and systems are as follows. First, offshore wind farms are large-scale projects, and it is necessary to consider the landscape from the pre-planning stage, as in overseas cases. Second, the evaluation items for marine landscape quality should be expanded and systematized. Third, a flexible evaluation system that can consider new landscape impacts is required. In order to identify the landscape impacts of offshore wind farm projects, we refer to the landscape assessment items and procedures derived from overseas cases, but reflect them appropriately to the domestic maritime conditions, and specifically introduce a plan to minimize the landscape impacts that may occur during offshore wind farm projects to contribute to the sustainable use of offshore wind power.

• Journal of The Geomorphological Association of Korea
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• v.17 no.3
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• pp.59-75
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• 2010

In this study, location evaluation of the natural environment of ports in the Joseon Dynasty was carried out to investigate the outport of east coast for the conquest of Usanguk. As a result of study, there were 55 ports and naval stations in the Joseon Dynasty, including the Yeongokpo, Aninpo, Samcheokpo, Susanpo, and Wolsongpo. As a result of the restoration work in the sea level that was done in the sixth century, the sea level at that time was about 1m higher than that at present. In terms of the location type, three types were identified via natural-environment analysis. Location type I consists of a total of 21 ports suitable for defense due to the sand spit in all the sides and because it is located in the bay of small and medium rivers. Location type II is composed of 22 ports close to the open seas, and location type III consists of a total of 12 ports centering on the bay. A total of nine ports satisfied the location factor in the shortest distance analysis(targeting location type I), 15 ports in the slope analysis, 13 ports in the hinterland analysis, 13 ports in the visibility analysis, and 11 ports in the ocean current analysis. It was found in the final evaluation that the I level regions consist of two ports(Obunjin and Mangyangjin). Obunjin has a location characteristic that is advantageous for defense and that makes it suitable to serve as an anchorage harbor for a large-scale fleet as its water level is deep and as it has a wide embayment. In conclusion, Obunjin is considered the outport that has the highest possibility of serving as Isabu's departure port for the conquest of Usanguk.

• Journal of Korea Water Resources Association
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• v.55 no.spc1
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• pp.1283-1293
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• 2022

The purpose of this study is to predict residual chlorine in order to maintain stable residual chlorine concentration in sedimentation basin by using artificial intelligence algorithms in water treatment process employing pre-chlorination. Available water quantity and quality data are collected and analyzed statistically to apply into mathematical multiple regression and artificial intelligence models including multi-layer perceptron neural network, random forest, long short term memory (LSTM) algorithms. Water temperature, turbidity, pH, conductivity, flow rate, alkalinity and pre-chlorination dosage data are used as the input parameters to develop prediction models. As results, it is presented that the random forest algorithm shows the most moderate prediction result among four cases, which are long short term memory, multi-layer perceptron, multiple regression including random forest. Especially, it is result that the multiple regression model can not represent the residual chlorine with the input parameters which varies independently with seasonal change, numerical scale and dimension difference between quantity and quality. For this reason, random forest model is more appropriate for predict water qualities than other algorithms, which is classified into decision tree type algorithm. Also, it is expected that real time prediction by artificial intelligence models can play role of the stable operation of residual chlorine in water treatment plant including pre-chlorination process.

• Journal of Korea Water Resources Association
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• v.55 no.spc1
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• pp.1235-1249
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• 2022

This study applied the web crawling technique for extracting big data news on water quality accidents in the water supply system and presented the algorithm in a procedural way to obtain accurate water quality accident news. In addition, in the case of a large-scale water quality accident, development patterns such as accident recognition, accident spread, accident response, and accident resolution appear according to the occurrence of an accident. That is, the analysis of the development of water quality accidents through key keywords and sentiment analysis for each stage was carried out in detail based on case studies, and the meanings were analyzed and derived. The proposed methodology was applied to the larval accident period of Incheon Metropolitan City in 2020 and analyzed. As a result, in a situation where the disclosure of information that directly affects consumers, such as water quality accidents, is restricted, the tone of news articles and media reports about water quality accidents with long-term damage in the event of an accident and the degree of consumer pride clearly change over time. could check This suggests the need to prepare consumer-centered policies to increase consumer positivity, although rapid restoration of facilities is very important for the development of water quality accidents from the supplier's point of view.

• Nuclear Engineering and Technology
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• v.26 no.1
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• pp.140-148
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• 1994

A qualification test was performed for the iron removal chemical cleaning of the secondary side of nuclear steam generators at the selected temperature, 1$25^{\circ}C$, higher than the standard application temperature, 93$^{\circ}C$. The field cleaning condition for a nuclear unit was tested in a bench scale test loop including a SUS 316 stainless steel autoclave with one gallon capacity as a test vessel. The kinetics of sludge dissolution, corrosion of the secondary side materials and change of solvent chemistry were monitored. Test results indicated that more thorough cleaning was accomplished in less than half of the cleaning time required at 93$^{\circ}C$. And the total corrosions of the secondary side materials were found to be less than the values at 93$^{\circ}C$. While the solvent is recirculated and heated by an external chemical cleaning equipment for the conventional 93$^{\circ}C$ process, the secondary side is heated by the lateral heat of the primary coolant without the recirculation of the cleaning solution, and the solvent is mixed by vigorous boiling induced by periodic ventilation for the high temperature process. The requirement that the reactor coolant pumps should be running during the cleaning operation is the major disadvantage of the high temperature process which also should be considered when chemical cleaning is planned for steam generators under operation.