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A Study on the Effect of Elementary Pre-service Teachers on Conceptual Acquisition and Perception Change of Strata and Rocks after Geological Exploration (초등예비교사들의 지질답사를 통한 지층과 암석 개념습득 및 인식변화에 대한 연구)

  • Yong-seob Lee
    • Journal of the Korean Society of Earth Science Education
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    • v.16 no.3
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    • pp.319-327
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    • 2023
  • This study involved 22 students in one class of 4th year science intensive course at B College of Education. We investigated the changes in the acquisition of knowledge in the field of geology and the perception of geological exploration among pre-service teachers. For this study, a period of four weeks was designated for a semester to a geological field trip. For the geological exploration, the Geoparks of City B (Geumjeongsan Mountain, Amnam Park, Igidae, Dusong Peninsula, Jangsan, Taejongdae, and Hwangnyeongsan Mountain) were designated. The concept of geology and rocks has been extracted from the concepts that can be found in the Geopark. The composition of the group was composed of one group of four members autonomously. The other two of the pre-service teachers joined a group of friends with whom they had an affinity. After the geological field trip, the materials were organized by group and PPT presentations were made during the lecture time where all the members could listen. The extent to which the pre-service teachers acquired the concepts of geology and rocks after conducting the geological field trip was interpreted as the result of pre- and post-statistical processing. In addition, we interpreted what kind of perception the pre-service teachers had after the geological field trip as a result of the statistical processing before and after. Based on the results of the study, the following conclusions were drawn: First, it was effective for the pre-service teachers to acquire the concepts of strata and rocks after the geological field trip. The reason for this is that the experience of the pre-service teachers in conducting geological field trips has changed their perception of geological field trips. In addition, it is interpreted that these results were obtained because the pre-service teachers had a high level of interest in geology and rocks. Second, the pre-service teachers were able to gain confidence after the geological field trip. This reason is interpreted as the fact that they were able to gain confidence in geological exploration by exploring and experiencing the sites of the Geopark for each group.

Comparison of Biological Responses and Heat Shock Protein 70 Expression in Chironomidae by Exposure UV and O3 (UV와 O3 노출에 따른 깔따구류의 생물학적 반응 및 열충격 단백질 70 발현)

  • Ji-Hoon Kim;Won-Seok Kim;Jae-Won Park;Bong-Soon Ko;Kiyun Park;Ihn-Sil Kwak
    • Korean Journal of Ecology and Environment
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    • v.56 no.4
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    • pp.430-439
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    • 2023
  • UV and O3 are materials used in the water treatment process, and many studies have been reported to remove organic matters, contaminants, and microorganisms. In this study, we were investigated effects of Chirnomidae (Chironomus flaviplumus, Chironomus riparius), which are contamination indicator species to exposure UV and O3 for the survival rate, body color change and gene expression response. The survival rate of C. flaviplumus exposed to UV decreased to about 70% after 24 hours, and C. riparius about 50%. There was no change in the survival rate of C. flaviplumus exposed to O3, and C. riparius decreased to 95% after 10 minutes of exposure, but there was no change during the subsequent exposure time. In addition, UV and O3 exposure to the two species in body color faded in a time-dependent. In the HSP70 gene expression, C. riparius showed an increase in expression after UV exposure compared to the control group, and a significant difference was shown 12 hours after exposure (P<0.05). C. flaviplumus exposed to O3 showed a relatively low expression compared to the control group, and showed a significant difference at 10 minutes and 1 hour after exposure (P<0.05). These results reported the ecotoxicological effects on Chironomidae according to UV and O3 exposure. Therefore, the results of this study can be used as basic data to understand the effects of UV and O3, which are disinfectants used in water treatment plants, on Chirnomidae entering plants.

Yeomjae Song Tae-hoe Origin and art world of calligraphy and painting (염재(念齋) 송태회(宋太會) 서화의 연원과 예술세계)

  • Kim Doyoung
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.5
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    • pp.255-262
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    • 2023
  • In the early 20th century, Yeomjae Song Tae-hoe (念齋 宋泰會, 1872-1941), a disciple and onetime adopted son of teacher Song Su-myeon(宋修勉, 1847-1916), moved to Gochang and laid the foundation for Gochang calligraphy and painting, and it can be seen that a full-fledged flow began. Yeomjae Song Tae-hoe was a scholar and calligrapher of the late Joseon Dynasty and modern period from Hwasun, Jeollanam-do. He is a person who created the foundation of Gochang calligraphy and painting while working as an educator in Chinese literature, calligraphy, and painting, mainly in his hometown of Hwasun and Gochang, while engaging in creative activities. He was intelligent from a young age and showed an extraordinary talent for calligraphy. At the age of 16, he passed the Jinsa exam (童蒙進士) and became the youngest student to study at Sungkyunkwan. He was active by holding exhibitions nationwide based in Gochang and Jeonju, and was also an educator who fostered younger students by establishing Gochang High School (currently, Gochang Middle and High School) to cultivate national spirit and history. Yeomjae drew strong and healthy landscape paintings under the absolute influence of the painting style of Saho Song Su-myeon, and dealt with various materials of southern school literati paintings such as flowers and birds and four plants. In particular, he is a representative calligrapher who encompasses the early modern era and the modern era in that he expressed his interest in new cultural artifacts as well as the realization of a modern-oriented realistic landscape based on Korean natural beauty. He laid the foundation for modern and contemporary calligraphy and painting. Goam Lee Eung-no (顧菴 李應魯, 1904-1989), a world-renowned painter, learned the basics of ink painting from Yeomjae in his late teens.However, compared to his various artistic and social activities, it is regrettable that he is limited and evaluated as a local writer.

Monitoring of Residual Pesticides in Pepper Seed Oil Products Sold on the Market (고추씨 기름의 잔류농약 모니터링)

  • Mi-Hui Son;Jae-Kwan Kim;You-Jin Lee;Ji-Eun Kim;Eun-Jin Baek;Byeong-Tae Kim;Myoung-Ki Park;Yong-Bae Park
    • Journal of Food Hygiene and Safety
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    • v.38 no.6
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    • pp.483-488
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    • 2023
  • The status of residual pesticides was investigated in four pepper seed oil samples and 36 pepper-flavored oil samples oil distributed on the market from August to December 2022. A total of 179 pesticides were monitored in 40 samples, and 14 pesticides were detected in 39 of the samples, with a detection range of 0.01-2.16 mg/kg. In chili seed oil, 10 pesticides were detected 27 times with a range of 0.11-2.16 mg/kg, and in pepper-flavored oil, 9 pesticides were detected 94 times with a range of 0.01-0.80 mg/kg. The most frequently detected pesticides were tebuconazole, ethion, and difenoconazole, with ethion being detected in large concentrations in products using Chinese raw materials. Ethion, an unregistered pesticide in the Republic of Korea, has not been detected in the Gyeonggi-do area in the past 10 years. It is thought that the detection of ethion can be utilized as an indicator of products made in China. Peppers are a representative agricultural product for which many pesticides are used, and if the pesticides transferred to pepper seeds are not removed, the probability of detecting various types of pesticides in pepper seed oil is very high. Therefore, continuous research is needed to ensure the safety of pepper seed oil.

Suggestions of Stone Materials for Restoration of Gwanghwamun Woldae in Seoul Based on Lithological Study (암석학적 연구를 통한 서울 광화문 월대 복원용 석재 제안)

  • Myeong Seong Lee;Yu Bin Ahn;Se Rin Park;Myoungju Choie;Jiyoung Kim
    • Economic and Environmental Geology
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    • v.56 no.6
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    • pp.647-659
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    • 2023
  • This study is to analyze the lithological similarities between railing stones of Gwanghwamun Woldae and stone blocks stored in Donggureung Royal Tombs, Guri, to interpret the provenance of the stones, and to suggest the most suitable quarry for a new stones supply among the rocks in the Seoul-Pocheon area in order to select stones for the restoration of the Gwanghwamun Woldae. The railing stones in Donggureung are medium to coarse-grained pink biotite granite, and their lithological characteristics, magnetic susceptibility(Average 5.20 ×10-3 SI unit), and gamma spectrometer data(K 5.00~6.38%, U 4.92~8.56 ppm, Th 27.60~36.44 ppm) show similarities with the remaining railing stones in Gwanghwamun Woldae(Average 5.38). Therefore, the railing stones in Donggureung can be reused for the restoration of Gwanghwamun Woldae. They have similar lithological and geochemical charateristics to the pink biotite granite found the Suraksan Mt. and Buramsan Mr. areas in Seoul, suggesting that these areas are the source of the stone. However, since the Suraksan Mt. and Buramsan Mt. areas are currently unavailable for quarrying, lithological and geochemical analyses on granite from the Yangju and Pocheon areas are conducted to determine the suitability of the new stone for restoration. As a result, a pink biotite granite similar to the Woldae stones was identified in the Pocheon area, and it is suggested that the stones similar in grain size and colour to the railing stones of Gwanghwamun Woldae should be selected and used for the restoration of Gwanghwamun Woldae.

Children's and Young Adult Literature in Library and Information Science Departments in the Republic of Korea: A Study of the Current State of Education and Suggestions for Future Directions (한국 문헌정보학 교과과정에서의 어린이청소년 문학 교육 현황 및 개선 방안 연구)

  • Yeojoo Lim
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.34 no.4
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    • pp.303-329
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    • 2023
  • This study aimed to investigate the current state and suggest future directions of children's and young adult literature education in Library and Information Science(LIS) departments in Korean universities. Courses related to children's and young adult literature in 34 LIS departments in Korea were investigated, and in-depth interviews and surveys were conducted with professors and instructors who have experience teaching courses related to children's and young adult literature in LIS departments. The results show there are on average 1.7 courses related to children's and young adult literature in undergraduate programs. 36% of schools had less than one course related to children's and young adult literature, and most of them were Reading Guidance courses. 83%(24 out of 29 people)of the survey participants said they teach children's and young adult literature in their classes. The professors and instructors spent the most of their lecture time on picture books. They spent the minimum time on genres such as SF, Fantasy, and manhwa. Lack of time to teach so many things in short 16 weeks made them feel rushed and distressed. Some survey respondents regarded themselves as non-experts in children's and young adult literature, even though they had competency in that field, which shows the general atmosphere in the LIS field that LIS people are not qualified enough to be experts in children's literature. All interviewees and some survey respondents insisted children's and young adult literature education in the LIS departments should be practical. Professors and instructors tried their best to incorporate diverse teaching methods, including discussions, storytelling, writing reviews, so their students can acquire proper knowledge on children's and young adult library services.

A study on quantification of α-quartz, cristobalite, kaolinite mixture in respirable dust using by FTIR (FTIR를 이용한 호흡성 분진중 α-quartz, cristobalite, kaolinite 혼합물 정량 분석 연구)

  • Eun Cheol Choi;Seung Ho Lee
    • Analytical Science and Technology
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    • v.36 no.6
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    • pp.315-323
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    • 2023
  • This study is to quantify α-quartz, cristobalite and kaolinite using by FTIR in respirable dust generated in the mining workplace. Various minerals in mines can interfere with peaks when quantifying respirable crystalline silica by FTIR. Therefore, for accurate quantification, it is necessary to remove interfering substances or correct the peaks that cause interference. To confirm the peaks occurring in α-quartz, cristobalite and kaolinite, each standard material was diluted with KBr and scanned in the range of 400 cm-1 to 4000 cm-1 using by FTIR. As a result of scanning the analytes, it was decided to use the peaks of 797.66 cm-1 and 695.25 cm-1 for α-quartz, 621.58 cm-1 for cristobalite, and 3696.47 cm-1 for kaolinite. When the above materials are mixed, interference occurs at the peak for quantification, which is corrected by the calculation formula. The analysis of the mixture of α-quartz and cristobalite shows the average bias (%) of 2.64 (corrected) at α-quartz (797.66 cm-1), 5.61 (uncorrected) at α-quartz (695.25 cm-1) and 1.51 (uncorrected) at cristobalite (621.58 cm-1). The analysis of the mixture of α-quartz and kaolinite shows the average bias(%) of 1.79(corrected) at α-quartz (797.66 cm-1), 3.92 (corrected) at α-quartz (695.25 cm-1) and 2.58 (uncorrected) at kaolinite (3696.47 cm-1). The analysis of the mixture of cristobalite and kaolinite shows the average bias (%) of 2.15 (corrected) at cristobalite (621.58 cm-1), 4.32 (uncorrected) at kaolinite (3696.47 cm-1). The analysis of the mixture of αquartz and cristobalite and kaolinite shows the average bias (%) of 1.93(corrected) at α-quartz (797.66 cm-1), 6.47 (corrected) at α-quartz (695.25 cm-1) and 1.77 (corrected) at cristobalite (621.58 cm-1) and 2.61 (uncorrected) at kaolinite (3696.47 cm-1). The experimental results showed that the deviation caused by peak interference by two or three substances could be corrected to less than 6 % of the average deviation. This study showed the possibility of correcting and quantifying when various interfering substances that are difficult to remove are mixed.

An Analytical Study on the Seismic Behavior and Safety of Vertical Hydrogen Storage Vessels Under the Earthquakes (지진 시 수직형 수소 저장용기의 거동 특성 분석 및 안전성에 관한 해석적 연구)

  • Sang-Moon Lee;Young-Jun Bae;Woo-Young Jung
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.27 no.6
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    • pp.152-161
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    • 2023
  • In general, large-capacity hydrogen storage vessels, typically in the form of vertical cylindrical vessels, are constructed using steel materials. These vessels are anchored to foundation slabs that are specially designed to suit the environmental conditions. This anchoring method involves pre-installed anchors on top of the concrete foundation slab. However, it's important to note that such a design can result in concentrated stresses at the anchoring points when external forces, such as seismic events, are at play. This may lead to potential structural damage due to anchor and concrete damage. For this reason, in this study, it selected an vertical hydrogen storage vessel based on site observations and created a 3D finite element model. Artificial seismic motions made following the procedures specified in ICC-ES AC 156, as well as domestic recorded earthquakes with a magnitude greater than 5.0, were applied to analyze the structural behavior and performance of the target structures. Conducting experiments on a structure built to actual scale would be ideal, but due to practical constraints, it proved challenging to execute. Therefore, it opted for an analytical approach to assess the safety of the target structure. Regarding the structural response characteristics, the acceleration induced by seismic motion was observed to amplify by approximately ten times compared to the input seismic motions. Additionally, there was a tendency for a decrease in amplification as the response acceleration was transmitted to the point where the centre of gravity is located. For the vulnerable components, specifically the sub-system (support columns and anchorages), the stress levels were found to satisfy the allowable stress criteria. However, the concrete's tensile strength exhibited only about a 5% margin of safety compared to the allowable stress. This indicates the need for mitigation strategies in addressing these concerns. Based on the research findings presented in this paper, it is anticipated that predictable load information for the design of storage vessels required for future shaking table tests will be provided.

Evaluation of Application Possibility for Floating Marine Pollutants Detection Using Image Enhancement Techniques: A Case Study for Thin Oil Film on the Sea Surface (영상 강화 기법을 통한 부유성 해양오염물질 탐지 기술 적용 가능성 평가: 해수면의 얇은 유막을 대상으로)

  • Soyeong Jang;Yeongbin Park;Jaeyeop Kwon;Sangheon Lee;Tae-Ho Kim
    • Korean Journal of Remote Sensing
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    • v.39 no.6_1
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    • pp.1353-1369
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    • 2023
  • In the event of a disaster accident at sea, the scale of damage will vary due to weather effects such as wind, currents, and tidal waves, and it is obligatory to minimize the scale of damage by establishing appropriate control plans through quick on-site identification. In particular, it is difficult to identify pollutants that exist in a thin film at sea surface due to their relatively low viscosity and surface tension among pollutants discharged into the sea. Therefore, this study aims to develop an algorithm to detect suspended pollutants on the sea surface in RGB images using imaging equipment that can be easily used in the field, and to evaluate the performance of the algorithm using input data obtained from actual waters. The developed algorithm uses image enhancement techniques to improve the contrast between the intensity values of pollutants and general sea surfaces, and through histogram analysis, the background threshold is found,suspended solids other than pollutants are removed, and finally pollutants are classified. In this study, a real sea test using substitute materials was performed to evaluate the performance of the developed algorithm, and most of the suspended marine pollutants were detected, but the false detection area occurred in places with strong waves. However, the detection results are about three times better than the detection method using a single threshold in the existing algorithm. Through the results of this R&D, it is expected to be useful for on-site control response activities by detecting suspended marine pollutants that were difficult to identify with the naked eye at existing sites.

Development of a Molecular Selection Marker for Bacillus licheniformis K12 (Bacillus licheniformis K12 균주 분자 선발 마커 개발)

  • Young Jin Kim;Sam Woong Kim;Tae Wok Lee;Won-Jae Chi;Woo Young Bang;Ki Hwan Moon;Tae Wan Kim;Kyu Ho Bang;Sang Wan Gal
    • Journal of Life Science
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    • v.33 no.10
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    • pp.808-819
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    • 2023
  • This study was conducted to develop a selection marker for the identification of the Bacillus licheniformis K12 strain in microbial communities. The strain not only demonstrates good growth at moderate temperatures but also contains enzymes that catalyze the decomposition of various polymer materials, such as proteases, amylases, cellulases, lipases, and xylanases. To identify molecular markers appropriate for use in a microbial community, a search was conducted to identify variable gene regions that show considerable genetic mutations, such as recombinase, integration, and transposase sites, as well as phase-related genes. As a result, five areas were identified that have potential as selection markers. The candidate markers were two recombinase sites (BLK1 and BLK2), two integration sites (BLK3 and BLK4), and one phase-related site (BLK5). A PCR analysis performed with different Bacillus species (e.g., B. licheniformis, Bacillus velezensis, Bacillus subtilis, and Bacillus cereus) confirmed that PCR products appeared at specific locations in B. licheniformis: BLK1 in recombinase, BLK2 in recombinase family protein, and BLK3 and BLK4 as site-specific integrations. In addition, BLK1 and BLK3 were identified as good candidate markers via a PCR analysis performed on subspecies of standard B. licheniformis strains. Therefore, the findings suggest that BLK1 can be used as a selection marker for B. licheniformis species and subspecies in the microbiome.