• Korean Journal of Environment and Ecology
• /
• v.34 no.6
• /
• pp.530-542
• /
• 2020

This study surveyed the central mountain area of Demilitarized Zone (DMZ) from March to October 2018 to reveal the appearance patterns of freshwater fish. We collected 7,744 individuals of 43 species in 12 families with skimming nets and cast nets in 12 stations during the survey. The dominant species was Zacco koreanus (30.3%), and the subdominant species was Z. platypus (18.5%), followed by Rhynchocypris oxycephalus (10.0%), R. steindachneri (6.7%), Microphysogobio yaluensis (5.9%), Acheilognathus signifer (4.5%), Pungtungia herzi (4.2%), and Orthrias nudus (2.6%). Among the collected species, four were legally protected. They included Hemibarbus mylodon, which was a natural monument, and Lethenteron reissneri, A. signifer, and Pseudopungtungia tenuicorpa, which were class II endangered wildlife designated by the Ministry of Environment. Twenty Korean endemic species (46.5%) and one exotic species, Micropterus salmoides, were also collected. Additionally, three climate-change sensitive species, R. kumgangensis, Ladislavia taczanowskii, and Cottus koreanus, and three landlocked species, L. reissneri, C. koreanus, and Rhinogobius brunneus appeared. The dominant species in each station were Z. koreanus (15 stations), Z. platypus (four stations), R. oxycephalus (four stations), and C. koreanus (one station). The species dominance index decreased from upstream to downstream (mainstream of Gimhwanamdae Stream), while the species diversity index and the species richness index increased. The community structure of the rivers was divided into the uppermost stream, upper stream, Han River, and Imjin River. Compared to antecedent surveys, this study collected the highest number of species. Two new species (Sarcocheilichthys variegatus wakiyae and Micropterus salmoides) were caught, while six species (Siniperca scherzeri, Leiocassis ussuriensis, Brachymystax lenok tsinlingensis, Rhodeus ocellatus, Abbottina springeri, Aphyocypris chinensis) did not appear. Gimhwanamdaecheon Stream has high biological value with the inhabitation of many species, including species under legal protection and high diversity and richness index scores. This paper also discussed a protection plan for this area.

• Research in Plant Disease
• /
• v.26 no.4
• /
• pp.272-278
• /
• 2020

The severe lettuce damage caused by Paratylenchus projectus was first reported in 2019 in Korea. To find high-value rotation crops for the control of P. projectus, nine vegetables, Brassica juncea (leaf mustard), B. rapa subsp. nipposinica (kyona), B. oleracea var. italica (broccoli), B. rapa subsp. chinensis (bok choy), B. oleracea var. viridis (kale), B. oleracea var. gongylodes (kohlrabi), Cichorium endivia (endive), C. intybus (chicory), Ipomoea aquatica (morning glory) were planted in d-10-cm clay pots in greenhouse. The growth of vegetables was compared between inoculated with 3,000 P. projectus per 100 ㎤ of soil and non-inoculated. Treatments were replicated 10 times. After 100 days, the reduction of fresh top weight was 30.4% in C. intybus, 35.1% in I. aquatica, 36.9% in B. oleracea var. acephala, 40.5% in C. endivia, 42.1% in B. rapa, 47.5% in B. rapa subsp. nipposinica, 50.4% in B. oleracea var. gonglodes, 56.3% in B. oleracea var. italica, and 66.0% in B. juncea. Nematode multiplication rates (Pf/Pi) were lower in I. aquatica (0.64) and C. endivia (1.1), but higher in B. oleracea var. gongylodes (2.54). Considering these results, I. aquatica is suitable for the rotation crop with lettuce until better rotation crops developed.

• Science of Emotion and Sensibility
• /
• v.24 no.1
• /
• pp.105-114
• /
• 2021

This study determines the differences between Korean female university students and their Chinese counterparts residing in Korea by evaluating the subjective sensation and tactile preference in fabrics for casual shirts. Seven types of white causal shirt fabrics were selected as specimens from those available in spring and autumn shirt collection. The fabrics were made from various fibers (cotton 100%, polyester 100%, flax 100%, polyester 80%/cotton 20%, polyester 65%/cotton 35%, polyester 50%/cotton 45%/spandex 5%, and polyester 50%/modal 50%). Forty Korean and Chinese female university students subjectively assessed the subjective sensation of fabrics used for casual shirts. Participants were asked to observe the seven types of fabrics and complete the questionnaire. The subjective sensation to be assessed for white casual shirt fabrics was classified into the following four factors: smoothness, lightness, softness, and stretchiness. Subjective sensation factors showed partially significant differences by nationality. Korean female students evaluated cotton fabric as being light, whereas their Chinese counterparts evaluated the polyester/cotton/spandex blended fabric as light. Korean female students evaluated polyester/modal blended fabric as being stretchable. The tactile preference for fiber composition of the fabrics showed partially significant differences by nationality. Korean female students preferred cotton 80%/polyester 20% blended fabric, polyester 50%/cotton 45%/spandex 5% blended fabric, and flax 100% fabric. The subjective sensation of the fabrics had different effects on preferences by nationality. Smoothness and softness had positive effects on preferences for the fabrics of Korean students. However, smoothness, softness, and stretchiness had positive effects on the preferences of Chinese students. The subjective sensation and tactile preference for casual shirt fabrics showed a difference between Korean female students and their Chinese counterparts. Therefore, when planning casual shirt fabrics for female university students, it is necessary to reflect on these differences in subjective sensation and tactile preference.

• Journal of Technology Innovation
• /
• v.28 no.3
• /
• pp.1-28
• /
• 2020

This study examines whether the firm with high innovation efficiency realizes high operating performance. We measured innovation efficiency by the ratio of patent applications for R&D expenditure or R&D stock and measured operating performance by the ratio of operating income or operating cash flow to total assets for the following year. The sample consists of 1,880 manufacturing firm-years, which listed on the Korean Exchange between 2014 and 2017. We analyze the effect of innovation efficiency on operating performance using a model of Hirshleifer et al. (2013) results show that both innovation efficiency variables have a significantly positive relationship with the total asset operating margin. Besides, the following year's performance, measured by the total asset operating cash flow ratio, also shows a positive relationship with the two innovation efficiency variables at the 5% and 1% significance levels, respectively. The results indicate that high innovation efficiency firms that link the outcomes of R&D to more patent applications realize higher operating performance. Also, we divided the R&D-intensive and non-R&D-intensive industries and performed the same analysis. As a result, the innovation efficiency has a significant positive effect on operating margin in both industries. However, the effect of innovation efficiency on the operating cash flow is only significant in R&D-intensive industries. This study suggests that the effects of innovation efficiency are more consistent in the R&D-intensive industry. Additionally, we divided the high patent application and low patent applications industries and performed the same analysis. As a result, the innovation efficiency has a significant positive effect on operating margin in both industries. This study suggests that the effects of innovation efficiency are more consistent in the high patent application industry. We show that a firm's innovation efficiency is a critical factor for a firm's performance, while prior studies on the R&D performance have not considered the innovation efficiency of each firm. The evidence suggests that firms not only consider R&D expenditures but also improve the performance of companies by increasing innovation efficiency. Investors need to consider their innovation efficiency when evaluating the value of firms.

• Korean Journal of Remote Sensing
• /
• v.37 no.3
• /
• pp.515-530
• /
• 2021

This study is to estimate soil moisture (SM) using Sentinel-1A/B C-band SAR (synthetic aperture radar) images and Multiple Linear Regression Model(MLRM) in the Yongdam-Dam watershed of South Korea. Both the Sentinel-1A and -1B images (6 days interval and 10 m resolution) were collected for 5 years from 2015 to 2019. The geometric, radiometric, and noise corrections were performed using the SNAP (SentiNel Application Platform) software and converted to backscattering coefficient of VV and VH polarization. The in-situ SM data measured at 6 locations using TDR were used to validate the estimated SM results. The 5 days antecedent precipitation data were also collected to overcome the estimation difficulty for the vegetated area not reaching the ground. The MLRM modeling was performed using yearly data and seasonal data set, and correlation analysis was performed according to the number of the independent variable. The estimated SM was verified with observed SM using the coefficient of determination (R²) and the root mean square error (RMSE). As a result of SM modeling using only BSC in the grass area, R² was 0.13 and RMSE was 4.83%. When 5 days of antecedent precipitation data was used, R² was 0.37 and RMSE was 4.11%. With the use of dry days and seasonal regression equation to reflect the decrease pattern and seasonal variability of SM, the correlation increased significantly with R² of 0.69 and RMSE of 2.88%.

• Atmosphere
• /
• v.31 no.2
• /
• pp.229-240
• /
• 2021

The Global Ocean Data Assimilation and Prediction System (GODAPS) in operation at the KMA (Korea Meteorological Administration) is introduced. GODAPS consists of ocean model, ice model, and 3-d variational ocean data assimilation system. GODAPS assimilates conventional and satellite observations for sea surface temperature and height, observations of sea-ice concentration, as well as temperature and salinity profiles for the ocean using a 24-hour data assimilation window. It finally produces ocean analysis fields with a resolution of 0.25 ORCA (tripolar) grid and 75-layer in depth. This analysis is used for providing a boundary condition for the atmospheric model of the KMA Global Seasonal Forecasting System version 5 (GloSea5) in addition to monitoring on the global ocean and ice. For the purpose of evaluating the quality of ocean analysis produced by GODAPS, a one-year data assimilation experiment was performed. Assimilation of global observing system in GODAPS results in producing improved analysis and forecast fields with reduced error in terms of RMSE of innovation and analysis increment. In addition, comparison with an unassimilated experiment shows a mostly positive impact, especially over the region with large oceanic variability.

• Korean Journal of Remote Sensing
• /
• v.37 no.3
• /
• pp.531-542
• /
• 2021

Open-pit mines require constant monitoring as they can cause surface changes and environmental disturbances. In open-pit mines, there is little vegetation at the mining site and can be monitored using InSAR (Interferometric Synthetic Aperture Radar) coherence imageries. In this study, activities occurring in mine were analyzed by applying the recently developed InSAR coherence-based NDAI (Normalized Difference Activity Index). The March 5 Youth Mine is a North Korean mine whose development has been expanded since 2008. NDAI analysis was performed with InSAR coherence imageries obtained using Sentinel-1 SAR images taken at 12-day intervals in the March 5 Youth Mine. First, the area where the elevation decreased by about 75.24 m and increased by about 9.85 m over the 14 years from 2000 was defined as the mining site and the tailings piles. Then, the NDAI images were used for time series analysis at various time intervals. Over the entire period (2017-2019), average mining activity was relatively active at the center of the mining area. In order to find out more detailed changes in the surface activity of the mine, the time interval was reduced and the activity was observed over a 1-year period. In 2017, we analyzed changes in mining operations before and after artificial earthquakes based on seismic data and NDAI images. After the large-scale blasting that occurred on 30 April 2017, activity was detected west of the mining area. It is estimated that the size of the mining area was enlarged by two blasts on 30 September 2017. The time-averaged NDAI images used to perform detailed time-series analysis were generated over a period of 1 year and 4 months, and then composited into RGB images. Annual analysis of activity confirmed an active region in the northeast of the mining area in 2018 and found the characteristic activity of the expansion of tailings piles in 2019. Time series analysis using NDAI was able to detect random surface changes in open-pit mines that are difficult to identify with optical images. Especially in areas where in situ data is not available, remote sensing can effectively perform mining activity analysis.

• Journal of radiological science and technology
• /
• v.40 no.1
• /
• pp.27-34
• /
• 2017

The author investigated interventional radiology patient doses in several other countries, assessed accuracy of DAP meters embedded in intervention equipments in domestic country, conducted measurement of patient doses for 13 major interventional procedures with use of Dose Area Product(DAP) meters from 23 hospitals in Korea, and referred to 8,415 cases of domestic data related to interventional procedures by radiation exposure after evaluation the actual effectives of dose reduction variables through phantom test. Finally, dose reference level for major interventional procedures was suggested. In this study, guidelines for patient doses were $237.7Gy{\cdot}cm^2$ in TACE, $17.3Gy{\cdot}cm^2$ in AVF, $114.1Gy{\cdot}cm^2$ in LE PTA & STENT, $188.5Gy{\cdot}cm^2$ in TFCA, $383.5Gy{\cdot}cm^2$ in Aneurysm Coil, $64.6Gy{\cdot}cm^2$ in PTBD, $64.6Gy{\cdot}cm^2$ in Biliary Stent, $22.4Gy{\cdot}cm^2$ in PCN, $4.3Gy{\cdot}cm^2$ in Hickman, $2.8Gy{\cdot}cm^2$ in Chemo-port, $4.4Gy{\cdot}cm^2$ in Perm-Cather, $17.1Gy{\cdot}cm^2$ in PCD, and $357.9Gy{\cdot}cm^2$ in Vis, EMB. Dose referenece level acquired in this study is considered to be able to use as minimal guidelines for reducing patient dose in the interventional radiology procedures. For the changes and advances of materials and development of equipments and procedures in the interventional radiology procedures, further studies and monitorings are needed on dose reference level Korean DAP dose conversion factor for the domestic procedures.

• Journal of Korean Classical Literature and Education
• /
• no.39
• /
• pp.67-97
• /
• 2018

The purpose of this paper is to clarify that the difference between past and present response to the same folktales relates to other cultural contexts. This is part of the research to explore the methodology of folktale education for intergenerational communication. This paper compares the reaction on a storytelling site from the past to with current college students' impressions. On the older site, the storyteller and audience sympathized with the characters of . Additionally, they were pleased with the conclusion that the characters would get a new family. However, university students thought that the characters of was incompetent. University students evaluated their success as depending on other people, accidentally obtained. Such a difference was closely related to the culture of the group intervening when understanding the folktale. In the past culture, empathy, interdependence, and unity were considered important values. Meanwhile, the new-generation culture emphasized the individual's free will and rights, diligence, and honesty. As a result, due to differences in cultural context, university students distorted , and communication with past generations was also broken. In this paper, we study the folktale education methodology that helps communication between generations. this paper proposes that It is more suitable to tile the story instead of for university students. That is because resembles the cultural context of university students. At the same time, it has the same problem as .

• Journal of Korean Classical Literature and Education
• /
• no.39
• /
• pp.221-246
• /
• 2018

In this text, the author examines the aspects and characteristics of the three forms that were created and enjoyed when the upper-class nobles of Japan "combined(混淆)" waka(和歌) and Chinese poetry(漢詩) between the 10th and 17th centuries. The three forms are the "Collection of Japanese and Chinese poems for singing"(和漢朗詠), "A collection of Japanese and Chinese poems" (詩歌合), and the "Renku renga"(聯句連歌). "Collection of Japanese and Chinese poems for singing" appeared in the 10th century, "A collection of Japanese and Chinese poems" appeared in the 12th century, "Renku renga" appeared in the 14th century, and all three continued to influence the history of Japanese literature after that time. As the combination of literary Japanese and Chinese progressed, the gap between waka and Chinese poetry decreased until they finally combined to create a single work. That is, waka and Chinese poetry converged in one place in multiple ways: as a work that was appropriate to be recited("Collection of Japanese and Chinese poems for singing"), facing each other work against work in a competition("A collection of Japanese and Chinese poems"), and, in the end, they reached the point where they were interchangeable as lines making up long poems(長詩)("Renku renga"). The combination of literary Japanese and Chinese can be said to be the Japanese version of the common movement in East Asian literary history during the Middle Ages to make songs from one's own language flawless in Chinese poetry. Meanwhile, by examining the status changes that appeared as Chinese poetry paralleled, fought with, replaced, and combined with waka, we can find clues to explain the attitudes of the Japanese people on Chinese poetry during the period when the three forms existed, as well as the characteristics of Japanese Chinese poetry that appeared in response to that. The preferences not of "myself" but of the "audience," content and expressions that revere the period rather than the inner self of the poet, and the fact that it is a means for enjoyable pleasure rather than having the original characteristics of lyrical poetry for self-expression are all characteristics of Chinese poetry in Japan during the early and late Middle Ages period. These characteristics can be said to be the current that flows in the underbelly of the history of Chinese literature in Japan. This author believes that the key to discussing the history of Chinese literature in Japan during the Middle Ages period from the perspective of East Asian literary history can be found here.