• Journal of Korea Water Resources Association
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• v.55 no.10
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• pp.761-774
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• 2022

Accurate hydrologic prediction is essential to analyze the effects of drought, flood, and climate change on flow rates, water quality, and ecosystems. Disentangling the uncertainty of the hydrological model is one of the important issues in hydrology and water resources research. Hydrologic data assimilation (DA), a technique that updates the status or parameters of a hydrological model to produce the most likely estimates of the initial conditions of the model, is one of the ways to minimize uncertainty in hydrological simulations and improve predictive accuracy. In this study, the two ensemble-based sequential DA techniques, ensemble Kalman filter, and particle filter are comparatively analyzed for the daily discharge simulation at the Yongdam catchment using airGRdatassim. The results showed that the values of Kling-Gupta efficiency (KGE) were improved from 0.799 in the open loop simulation to 0.826 in the ensemble Kalman filter and to 0.933 in the particle filter. In addition, we analyzed the effects of hyper-parameters related to the data assimilation methods such as precipitation and potential evaporation forcing error parameters and selection of perturbed and updated states. For the case of forcing error conditions, the particle filter was superior to the ensemble in terms of the KGE index. The size of the optimal forcing noise was relatively smaller in the particle filter compared to the ensemble Kalman filter. In addition, with more state variables included in the updating step, performance of data assimilation improved, implicating that adequate selection of updating states can be considered as a hyper-parameter. The simulation experiments in this study implied that DA hyper-parameters needed to be carefully optimized to exploit the potential of DA methods.

• Journal of the Korean Orthopaedic Association
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• v.56 no.6
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• pp.504-511
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• 2021

Purpose: This study examined the difference between the drainage volume, blood loss, transfusion rate, volume, and complications with or without an intra-articular (IA) tranexamic acid (TXA) injection among patients who underwent simultaneous bilateral total knee arthroplasty (SBTKA) with bilateral knee joint osteoarthritis, including patients who have contraindications of intravenous administration. Materials and Methods: Among patients who underwent SBTKA from April 2016 to December 2018, 139 patients injected with 3 g of TXA in each side through a drainage tube after joint capsule repair (group T), and 57 patients (group A) who underwent the procedure without TXA between October 2007 and August 2010 were tested. No significant difference in age and sex was observed between the two groups (p=0.572, 0.474). TXA was injected in patients with contraindications of intravenous administrations. Patients who underwent SBTKA with inflammatory arthritis were excluded from this study. The average amount of drainage, blood loss, transfusion rate, volume and daily average transfusion rate, and hemoglobin (Hb) change by the postoperative day were compared. Complications, such as deep vein thrombosis, pulmonary thromboembolism, myocardial infarction, cerebral infarction, and infection, were investigated. Results: The average total blood losses in groups A and T were 2195.32±1175.63 ml and 1145.09±382.95 ml, respectively, and the average total drain volume was 1,178.30±48.59 ml and 774.19±310.06 ml, respectively; both were significantly lower in group T (p=0.002, <0.001). The transfusion rates were 77.2% (44/57) and 0.7% (1/139), which were significantly lower in group T (p<0.001). The total average transfusion volume in groups A and T were 735.44±550.83 ml and 4.60±54.28 ml, respectively, which were significantly lower in group T (p<0.001). Hb tended to increase for three or four days after surgery in group A and group T. Regarding complications, deep vein thrombosis was encountered in two cases (1.4%), and pulmonary thromboembolism was noted in three cases (2.2%) in group T, but there were no cases in group A. No infections, cerebral infarction, or myocardial infarction occurred. Conclusion: In SBTKA, IA injections of TXA reduced the average drain volume, blood loss, transfusion rate, and volume significantly and did not increase the incidence of complications, even in patients with contraindications of intravenous administration.

• Journal of the Korean Orthopaedic Association
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• v.55 no.1
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• pp.78-84
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• 2020

Purpose: This paper compares the clinical outcomes of patients who were treated with a cervical nerve block by ultrasound and C-arm and reports the complication. Materials and Methods: A total of 97 patients were treated with an ultrasound-guided nerve root block from May 1, 2015 to February 8, 2018. On the other hand, 94 patients were treated with a C-arm guided nerve root block. The consequences of the cervical pain and the radiating pain before and after the procedures were reviewed using the verbal numeric rating scale (VNRS). In addition, the complications related to the procedures from the daily notes from the chart were inspected. Results: Sixty-six cases out of 97 cases of ultrasound-guided nerve root block were enrolled in the study. The average age of the patients was 57 years, including 41 males and 25 females. Seventy seven out of 94 cases by a C-arm guided root block were included in the study. The average age of the patients was 55 years, including 40 males and 37 females. Before the nerve root block, the mean numeric rating pain scale (NRS) of the cervical pain in ultrasound-guided block decreased from 5.4 points to 2.7 points at three weeks and 1.4 points at six weeks (p=0.0023, p<0.001), and 3.1 points in the C-arm (p<0.001, p<0.001) at three weeks and 1.5 points at six weeks (p<0.001, p<0.001). In the case of radiating pain, the mean NRS in the ultrasound-guided nerve root block group improved from 6.3 points after the procedure to 2.8 points at three weeks and 1.5 points at six weeks (p<0.001, p<0.001). In the C-arm guided nerve root block group, the NRS improved from 7.4 points after the procedure to 3.3 points at three weeks and 1.9 points at six weeks. In the case of complications, Horner's syndrome and propriospinal myoclonus were observed in one case of C-arm guided block group. Conclusion: The clinical results of the patients who underwent ultrasound-guided cervical nerve root block were not significantly different from those who underwent a C-arm guided cervical nerve root block.

• Journal of Ginseng Culture
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• v.4
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• pp.103-127
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• 2022

The influx of modern culture in the early 20th century in Korea led to numerous changes in the country's ginseng industry. With the development of ginseng cultivation technology and commerce, the production and consumption of ginseng increased, and various ginseng products were developed using modern manufacturing technology. Consequently, competition for the sales of these products became fierce. At that time, newspaper advertisements showed detailed trends in the development and sales competition of ginseng products. Before 1920, however, there were few advertisements of ginseng in newspapers. This is thought to be because newspapers had not yet been generalized, and the ginseng industry had not developed that much. Ginseng advertisements started to revitalize in the early 1920s after the launch of the Korean daily newspapers Dong-A Ilbo and Chosun Ilbo. Such advertisements in this period focused on emphasizing the traditional efficacy of Oriental medicine and the mysterious effects of ginseng. There were many advertisements for products that prescribed the combination of ginseng and deer antler, indicating the great popularity of this prescription at the time. Furthermore, advertisements showed many personal experience stories about taking such products. Mail order and telemarketing sales were already widely used in the 1920s . In 1925, there were advertisements that ginseng products were delivered every day. The advertisements revealed that ginseng roots were classified more elaborately than they are now according to size and quality. Ginseng products in the 1920s did not deviate significantly from the scope of traditional Oriental medicine formulations such as liquid medicine, pill, and concentrated extract. In the 1930s, ginseng advertisements became more active. At this time, experts such as university professors and doctors in medicine or in pharmacy appeared in the advertisements. They recommended ginseng products or explained the ingredients and medicinal effects of the products. Even their experimental notes based on scientific research results appeared in the advertisements to enhance the reliability of the ginseng products. In 1931, modern tablet advertisements appeared. Ginseng products supplemented with vitamins and other specific ingredients as well as ginseng thin rice gruel for the sick appeared at this time. In 1938, ginseng advertisements became more popular, and advertisements using talents as models, such as dancer Choi Seunghee or famous movie stars, models appeared. Ginseng advertisements in the 1920s and 1930s clearly show a side of our rapidly changing society at the time.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.6
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• pp.64-79
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• 2021

In Korea, mountains constitute 60 percent of the total land area. For a long time, mountains have been deeply involved in people's daily lives, acting as a significant layer of culture. For those reasons, it would be meaningful to shed light on the values of the mountain culture of Korea and seek various ways to utilize them. Therefore, this study aims to explore Korea's mountain enjoyment culture, considering the mountain leisure in the Joseon Dynasty period, when the heritage of mountain enjoying culture was prevalent, and that of the present era. For the analysis, hiking records of the Joseon Dynasty and present-day hiking blog posts related to three famous mountains in Korea were examined. Findings show that people stayed in the mountains for a long time in the Joseon Dynasty, concentrating on the landscape deeply, and various academic and artistic cultures flourished there. In contrast, contemporary people regard the mountain merely as a space to access the peak and climb down quickly within a day. Therefore, the landscape of the mountain cannot be used as a cultural asset beyond natural scenery. However, there are several positive aspects to today's climbing culture. For example, it is easy to obtain information on climbing and feasible ways to conduct various sizes and concepts of hiking due to the development of technology and transportation. In order to develop Korea's unique mountain enjoyment culture in the future, we should propose a 'leisurely hike' that allows people to enjoy the mountain scenery fully and sublimating it into culture, rather than being hiking that is limited to climbing. In addition, it is essential to create suitable spaces, arranging them appropriately to utilize the history and humanities context of the mountain, and connect local facilities and the workforce, thereby causing the development of various mountain enjoyment cultures.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.3
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• pp.164-178
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• 2022

Uncertainties in weather forecasts would affect the reliability of yield prediction using crop models. The objective of this study was to compare uncertainty in crop yield prediction caused by the use of the weather forecast data. Daily weather data were produced at 10 km spatial resolution using W eather Research and Forecasting (W RF) model. The nearest neighbor method was used to downscale these data at the resolution of 5 km (W RF5K). Parameter-elevation Regressions on Independent Slopes Model (PRISM) was also applied to the WRF data to produce the weather data at the same resolution. W RF5K and PRISM data were used as inputs to the CROPGRO-SOYBEAN model to predict crop yield. The uncertainties of the gridded data were analyzed using cumulative growing degree days (CGDD) and cumulative solar radiation (CSRAD) during the soybean growing seasons for the crop of interest. The degree of agreement (DOA) statistics including structural similarity index were determined for the crop model outputs. Our results indicated that the DOA statistics for CGDD were correlated with that for the maturity dates predicted using WRF5K and PRISM data. Yield forecasts had small values of the DOA statistics when large spatial disagreement occured between maturity dates predicted using WRF5K and PRISM. These results suggest that the spatial uncertainties in temperature data would affect the reliability of the phenology and, as a result, yield predictions at a greater degree than those in solar radiation data. This merits further studies to assess the uncertainties of crop yield forecasts using a wide range of crop calendars.

• Journal of Appropriate Technology
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• v.6 no.2
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• pp.174-182
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• 2020

The permissible limit of ammonia concentration in drinking water recommended by the World Health Organization (WHO) is 1.5 mg/L. However, in the case of groundwater in Kathmandu, Nepal, the concentration of ammonia fluctuates dramatically from 0 to 120 mg/L at different locations and groundwater depths (Chapagain et al., 2010). Such a high concentration of ammonia causes aesthetic problems in drinking water, such as bad taste and odor; hence, prior treatment is required. In Kathmandu, half of the population utilizes groundwater, which is also employed for drinking water, but owing to a lack of knowledge of household water filters, residents of Kathmandu tend to depend greatly on commercially available jar water than on the installation of a proper household filtration method. Thus, in our study, we employed adsorption and reverse osmosis (RO) as two of the most viable decentralized/household treatment options to address the issue of high contamination of ammonia in drinking water. We evaluated their performances from technical and the economic perspectives using synthetically prepared groundwater at varying ammonia concentrations (50 mg/L and 15 mg/L). Consequently, it was found that adsorption via ion exchange (IE) resin was a comparatively better ammonia removal technology than RO, with 100% ammonia removal even after regeneration; the removal by RO was limited to up to 90%. Furthermore, our study suggests that IE is the most suitable ammonia removal technology for places with lower water consumption (< 50 L/day), whereas RO seemed to be a cost-effective technology for places with higher water consumption, where the daily water demand exceeds 50 L/day. Lastly, these assessments suggest that installing a suitable household treatment system would be more efficient and sustainable from both technical and economic points of view than purchasing commercially bottled water.

• Journal of Korean Home Economics Education Association
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• v.33 no.2
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• pp.135-152
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• 2021

The purpose of this study was to examine the effectiveness of the curriculum implementation of 「Food Safety and Health」, a Home Economics elective course, for high school students. Accordingly, several units of the 「Food Safety and Health」curriculum were piloted in six high schools in Chungbuk, Gyeonggi, Daejeon, and Sejong, and 1,199 questionnaires collected from students who participated in the classes were analyzed. The results are as follows. The 「Food Safety and Health」class had a significant effect on improving the total score of 'food safety and health' knowledge of high school students and scores for sub-dimensional area. Compared to the pre-test, the overall rate of correct answers for the post-test has increased by 7.99%p, and schools that implemented the relevant unit class relatively more had higher improvement scores. In addition, the 「Food Safety and Health」class has positively changed the eating behavior of high school students, and had a significant effect on having a habit of eating a variety of foods evenly. High school students who participated in the 「Food Safety and Health」class evaluated their classes very positively (4.27 out of 5 points), and responded that the content of the class was interesting, easy to understand, and helpful for their diet in daily life. According to the responses to the open-ended questions, students responded that the class was helpful in acquiring food-related knowledge in their real lives, while there were so many limitations for experiencing lab class and group activities due to COVID 19. In preparation for the high school credit system, this study is meaningful that it has expanded the elective courses in home economics area, as well as the right to choose subjects for high school students.

• Journal of Popular Narrative
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• v.26 no.1
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• pp.243-277
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• 2020

This paper examines a social and cultural history of horror films through the keyword "technology", focusing on The Spark of Fear: Technology, Society and the Horror Film (2015) written by Brian N. Duchaney. Science fiction film is closely connected with technology in film genres. On the other hand, horror films have been explained in terms of nature/supernatural. In this regard, The Spark of Fear, which accounts for horror film history as (re)actions to the development of technology, is remarkable. Early horror films which were produced under the influence of gothic novels reflected the fear of technology that had been caused by industrial capitalism. For example, in the film Frankenstein (1931), an angry crowd of people lynch the "monster", the creature of technology. This is the action which is aroused by the fear of technology. Furthermore, this mob behavior is suggestive of an uprising of people who have been alienated by industrial capitalism during the Great Depression. In science fiction horror films, which appeared in the post-war boom, the "other" that manifests as aliens is the entity that destroys the value of prosperity during post-war America. While this prosperity is closely related to the life of the middle class in accordance with the suburbanization, the people live conformist lives under the mantle of technologies such as the TV, refrigerator, etc. In the age of the Vietnam War, horror films demonize children, the counter-culture generation against a backdrop of the house that is the place of isolation and confinement. In this place, horror arises from the absolute absence of technology. While media such as videos, internet, and smartphones have reinforced interconnectedness with the outside world since the 1980s, it became another outside influence that we cannot control. "Found-footage" and "torture porn" which were rife in post-9/11 horror films show that the technologies of voyeurism/surveillance and exposure/exhibitionism are near to saturation. In this way, The Spark of Fear provides an opportune insight into the present day in which the expectation and fear of the progress of technology are increasingly becoming inseparable from our daily lives.

• Journal of Popular Narrative
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• v.26 no.3
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• pp.123-160
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• 2020

Manga develops by reflecting a change of society, reader's needs, and their thoughts and changes of tastes, sensitively. Shojo manga and Jyosei manga also do. We can find several kinds of meaningful changes in Japanese Jyosei manga in the 2010s. The works which represent preciousness of daily life, women's narrative and self-realization are gradually increasing. In addition, the works that deal with very touchy issues such as sex discrimination at work, sexual harassment begin to emerge. It has never been found in the manga of the former era. While this paper analyzes the social and cultural causes of these changes of the works that exclude romance and treat gender issues focusing on recent works, it examines changes of Japanese Jyosei manga in the 2010s and their meanings. I investigate the current trends of Japanese Jyosei manga in the 2010s through Umimachi Diary that represents a precious everyday life with woman-centered narrative, Metamorphose no engawa that deals with women's story from a new perspective, Good-bye My Miniskirt that tackles gender issues. Furthermore I intensively analyze how Nagi's Long Vacation and Darucyan, which win popularity from women in their 20s~30, represent lives and troubles of contemporary Japanese women. Nagi's Long Vacation represents the heroine's quest for a self throwing everything out. While Darucyan deals with self-realization, it forms of a bond of sympathy of readers by representing the heroine who suffers sexual harassment and inequal conditions very realistically. Nagi's Long Vacation and Darucyan have something in common with portraying troubles and self-realization of the working women in their 20s based on a indigenous reality to Japanese society very realistically. However they are unusual in that it is different from the manga of the former era in dealing with heroine's troubles and their solutions. The most distinctive changes of Jyosei manga since 2010 are that real issues surfaced with social changes. In addition, these social contradictions result from irrational discriminations and old customs of Japanese society for a long time. Manga reflects subtly the portraits of the times, their images of women, and their values. These changes of Jyosei manga also show the concerns of readers at that time, and it means that women began to be aware of the issues.