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Research Trends of Foreign Countries on Geological Evaluation of Abiotic Hydrogen Productivity: A Review (비생물기원 수소 생산성의 지질학적 평가 관련 해외 연구 동향: 리뷰 논문)

  • Jeong, Seongwoo;Kim, Taeyong;Ko, Kyoungtae;Yang, Minjune
    • The Journal of Engineering Geology
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    • v.32 no.4
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    • pp.627-642
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    • 2022
  • The world's long reliance on fossil fuels (e.g., oil, coal, and natural gas) is severely changing its environment and climate. Energy research has focused on developing hydrogen as the most promising energy carrier and a key technology for sustainable energy development. Hydrogen can be classified as gray, blue, green, and otherwise according to the raw materials and methods used for production and processing. For the development of hydrogen energy, geologists are attempting to identify the mechanism of abiotic hydrogen generation by serpentinization or hydrothermal alteration. Teams in the United States, France, and Australia have researched laboratory-scale hydrogen production through water-rock interactions under various conditions, whereas there has been almost no research on abiotic hydrogen in South Korea. This paper reviews the current state of international research on hydrothermal alteration and offers suggestions for future investigations of abiotic hydrogen production in South Korea.

Study to Improve the Legal System to Reduce Marine Accidents caused by Marine Plastic Litter (해양 플라스틱 쓰레기에 의한 부유물 감김 해양사고 저감 정책방안 연구 - 법제도 측면 개선 중심으로 -)

  • Lee, Hye-Jin;Kim, Bo-Ram
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.7
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    • pp.967-976
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    • 2021
  • Over the last ten years, the number of entanglement marine accidents has increased more than other accident types. This study analyzed the annual statistical report of marine accidents from the Korea Maritime Safety Tribunal and Korea Coast Guard. Despite some discrepancies between data of the two organizations, it was found that marine accidents involving fishing vessels were more prevalent than those involving non-fishing vessels. In addition, the main floating materials that caused wounded entanglement accidents were fishing nets, fishing gear, and ropes, and the proportion of them was high. Foreign and domestic policies on marine plastics recognize most marine plastics as marine environmental hazards and focus on marine litter recovery and the prevention of marine pollution. The representative Acts related to the marine environment and marine litter, the Marine Environment Management Act and the Marine Waste and Sediments Management Act, recognize marine litter as a type of marine waste, and deal with the types and definition of this waste. However, clearly defining marine waste is difficult. Therefore, this study tried to examine the relevant legal system of marine litter on ship operation and suggested improvement measures. Moreover, the definition of marine litter for the safe navigation and operation of ships was clearly proposed.

Innovative Technologies in Higher School Practice

  • Popovych, Oksana;Makhynia, Nataliia;Pavlyuk, Bohdan;Vytrykhovska, Oksana;Miroshnichenko, Valentina;Veremijenko, Vadym;Horvat, Marianna
    • International Journal of Computer Science & Network Security
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    • v.22 no.11
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    • pp.248-254
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    • 2022
  • Educational innovations are first created, improved or applied educational, didactic, educative, and managerial systems and their components that significantly improve the results of educational activities. The development of pedagogical technology in the global educational space is conventionally divided into three stages. The role of innovative technologies in Higher School practice is substantiated. Factors of effectiveness of the educational process are highlighted. Technology is defined as a phenomenon and its importance is emphasized, it is indicated that it is a component of human history, a form of expression of intelligence focused on solving important problems of being, a synthesis of the mind and human abilities. The most frequently used technologies in practice are classified. Among the priority educational innovations in higher education institutions, the following are highlighted. Introduction of modular training and a rating system for knowledge control (credit-modular system) into the educational process; distance learning system; computerization of libraries using electronic catalog programs and the creation of a fund of electronic educational and methodological materials; electronic system for managing the activities of an educational institution and the educational process. In the educational process, various innovative pedagogical methods are successfully used, the basis of which is interactivity and maximum proximity to the real professional activity of the future specialist. There are simulation technologies (game and discussion forms of organization); technology "case method" (maximum proximity to reality); video training methodology (maximum proximity to reality); computer modeling; interactive technologies; technologies of collective and group training; situational modeling technologies; technologies for working out discussion issues; project technology; Information Technologies; technologies of differentiated training; text-centric training technology and others.

Development of a real-time polymerase chain reaction assay for reliable detection of a novel porcine circovirus 4 with an endogenous internal positive control

  • Kim, Hye-Ryung;Park, Jonghyun;Park, Ji-Hoon;Kim, Jong-Min;Baek, Ji-Su;Kim, Da-Young;Lyoo, Young S.;Park, Choi-Kyu
    • Korean Journal of Veterinary Service
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    • v.45 no.1
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    • pp.1-11
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    • 2022
  • A novel porcine circovirus 4 (PCV4) was recently identified in Chinese and Korean pig herds. Although several conventional polymerase chain reaction (cPCR) and real-time PCR (qPCR) assays were used for PCV4 detection, more sensitive and reliable qPCR assay is needed that can simultaneously detect PCV4 and internal positive control (IPC) to avoid false-negative results. In the present study, a duplex qPCR (dqPCR) assay was developed using primers/probe sets targeting the PCV4 Cap gene and pig (glyceraldehyde-3-phosphate dehydrogenase) GAPDH gene as an IPC. The developed dqPCR assay was specifically detected PCV4 but not other PCVs and porcine pathogens, indicating that the newly designed primers/probe set is specific to the PCV4 Cap gene. Furthermore, GAPDH was stably amplified by the dqPCR in all tested viral and clinical samples containing pig cellular materials, indicating the high reliability of the dqPCR assay. The limit of detection of the assay 5 copies of the target PCV4 genes, but the sensitivity of the assay was higher than that of the previously described assays. The assay demonstrated high repeatability and reproducibility, with coefficients of intra-assay and inter-assay variation of less than 1.0%. Clinical evaluation using 102 diseased pig samples from 18 pig farms showed that PCV4 circulated in the Korean pig population. The detection rate of PCV4 obtained using the newly developed dqPCR was 26.5% (27/102), which was higher than that obtained using the previously described cPCR and TaqMan probe-based qPCR and similar to that obtained using the previously described SYBR Green-based qPCR. The dqPCR assay with IPC is highly specific, sensitive, and reliable for detecting PCV4 from clinical samples, and it will be useful for etiological diagnosis, epidemiological study, and control of the PCV4 infections.

A Study on the Current Status of National Library of Korea Subject Headings List through Utilization Analysis of Subject Headings (주제명 활용 분석을 통한 국립중앙도서관 주제명표목표의 현황 연구)

  • HyeKyung Lee;Yong-Gu Lee
    • Journal of the Korean Society for information Management
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    • v.40 no.2
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    • pp.157-182
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    • 2023
  • This study analyzed the structure and utilization of subject headings in the National Library of Korea Subject Headings List (NLSH) based on an analysis of subject headings assigned to 1,218,867 national bibliographies from 2003 to 2022. The findings of the study are as follows: Firstly, among all subject headings in the NLSH, there were 257,103 preferred terms, accounting for 50.2% of the total terms. Foreign language terms constituted 33% (169,466), while non-preferred terms comprised 12% (61,442). Among the preferred terms, 57,312 subject headings were used, accounting for 22.3%. However, it was observed that 54.7% (31,351) of these subject headings were assigned less than 5 times, indicating that only a small number of subject headings were frequently utilized. Secondly, the frequency of relationship indicators appeared in the order of RT, BT, and NT. The NLSH consisted of 12,602 top-level subject headings and 143,704 lowest-level subject headings, with a maximum depth of 17 levels. Thirdly, on average, 1.72 subject headings were assigned per bibliographic record. The number of subject headings assigned and the depth of the hierarchy increased for materials with more specific contents. Recent bibliographic records have been assigned more subject headings and deeper into the hierarchy of the NLSH. It was also found that the number of subject headings assigned per bibliography varied depending on the main class of KDC. Based on the findings, it is recommended to evaluate the coverage of terms in the NLSH, reorganize hierarchical relationships and depth of subject headings, and enhance the development of subdivisions within the NLSH.

An Exploratory Research on Measuring the Local and Regional Impacts of Universities (대학이 지역에 미치는 영향 지표 개발을 위한 탐색적 연구)

  • Shin, Jin-Young;Lee, Jong-Ho
    • Journal of the Korean association of regional geographers
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    • v.23 no.3
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    • pp.437-449
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    • 2017
  • As a new duty of universities, contributions to localities and regions are magnified as an important issue and overseas universities are creating it as the index to use self evaluations and public relations actively. The universities in Korea are expanding resources usage of university and proceeding various businesses to enhance co-operation with local government, civic groups and companies lately. However, it is still in an embryo. This study is aiming to analyze cases of foreign universities and the socio-economic impacts of university on the region and discover evaluation index based on the results to be applied to the universities in Korea. This study had considered the evaluation of local effect by the university conducted by the Higher Education Funding Council for England(HEFCE) which is the representative case to analyze the impacts of university on the region at the level of government and independent organizations. The applicable common index had been extracted for universities in Korea from case studies on University of Rochester in the US and University of Birmingham in the UK considered as a representative university in North America and Europe respectively which are publishing a white paper on local and regional impacts of the university by using various index. As a result, 24 items in six areas(economic influence, research, education, art & cultural services, regional development, and the field of university specialization) had been deducted as the evaluation index which represents the local and regional impacts of university. This index could be secured through holding materials of each university and 'Higher Education in KOREA' as university information disclosure service and it might be applied to the universities in Korea.

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A Study on the Food-culture's Property of the Traditional Generation through the Oral Interview (구술을 통한 전통세대의 음식문화특성 연구)

  • Kim, Mi-Hye;Chung, Hae-Kyung
    • Journal of the Korean Society of Food Culture
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    • v.24 no.6
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    • pp.613-630
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    • 2009
  • This thesis, which involves honest life stories of members of the ìtraditionalî Korean generation that lived through the turbulent times of the first half of the twentieth century, assesses the meaning and import of Korean cuisine during an individual Korean's lifetime, as well as the relevant properties of the culinary culture of the traditional generation and how those properties continue to influence the present generation of Koreans. Thus, traditional Korean culinary culture was subdivided into the following four aspects, each of which were exemplified by representative examples. The first of these is slow-food dietary life, which is exemplified by fermented foods. The development of side dishes (panchan) based on fermentation - kimchi, different types of soy and bean paste, salted seafoods, dishes of dried radish or cucumber slices seasoned with soy sauce, and so on - made the quantitative and qualitative supplementation of food possible for traditional Koreans. The second of these aspects, referred to as friendly dietary life, is exemplified by self-sufficiently produced foods. The system of many species and small production suitable with the season made it possible to produce food from sustainable ecological systems and to maintain locally grown food-cultures, each of which was distinguished from others by a local specialty product. The third aspect of the traditional Korean culinary culture involves the same use of medicinal roots and plant materials for foodstuff, and this is exemplified by the use of foods to cure and prevent diseases. The notion, for example, that 'boiled rice is an invigorant' is characteristic of the notion that diet can function in a preventative medical context, and other similar Korean notions illustrate the importance, also, of the curative properties of food. The fourth and final aspect of traditional Korean culinary culture identified herein is creative dietary life, which can be viewed essentially as a Korean adaptation to the turbulence of life during the early $20^{th}$ century in Korea. This trend is exemplified by many Korean foods that were created in response to foreign influences, such as onions, cabbages, curry, etc. which found their place in overall Korean culture through the age of Japanese settlement, as well as the Korean war.

Effect of calcium silicate-based sealer to bone tissue of mandible of rats (칼슘 실리케이트 계열 실러가 흰쥐의 하악골 조직에 미치는 영향)

  • Jee-Seon Tae;Ki-Yeon Yoo;Jin-Woo Kim;Kyung-Mo Cho;Yoon Lee;Se-Hee Park
    • Journal of Dental Rehabilitation and Applied Science
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    • v.40 no.1
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    • pp.1-12
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    • 2024
  • Purpose: To histologically evaluate the effects of three calcium silicate-based sealers on rat mandible tissue. Materials and Methods: Rats were randomly divided as follows: A group that sacrificed immediately after cavity preparation, a group that sacrificed two weeks after cavity preparation, a group that sacrificed two weeks after CeraSeal (CS), AH Plus Bioceramic (AHB), or One-Fil (OF) sealer injection, respectively. After tissue processing for all groups, the bone tissue area (%) and the number of osteoclasts in and around the cavity were measured under a microscope. The results of each group were compared and statistical analysis was performed using one-way ANOVA and Tukey's test. Results: The formation of bone tissue and the presence of osteoclasts in the cavity were observed in the group that sacrificed two weeks after cavity preparation and the group sacrificed two weeks after AHB sealer injection, and these groups showed significantly higher average bone tissue area (%) than the other groups. In the other groups, no inflammation or foreign body reaction occurred in the cavity, and no osteoclasts were observed. Conclusion: All calcium silicate-based sealers used in this study showed a favorable bone tissue response when injected into the rat mandible. In particular, higher bone formation in the cavity was observed in AHB.

Comparison of One- and Two-Region of Interest Strain Elastography Measurements in the Differential Diagnosis of Breast Masses

  • Hee Jeong Park;Sun Mi Kim;Bo La Yun;Mijung Jang;Bohyoung Kim;Soo Hyun Lee;Hye Shin Ahn
    • Korean Journal of Radiology
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    • v.21 no.4
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    • pp.431-441
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    • 2020
  • Objective: To compare the diagnostic performance and interobserver variability of strain ratio obtained from one or two regions of interest (ROI) on breast elastography. Materials and Methods: From April to May 2016, 140 breast masses in 140 patients who underwent conventional ultrasonography (US) with strain elastography followed by US-guided biopsy were evaluated. Three experienced breast radiologists reviewed recorded US and elastography images, measured strain ratios, and categorized them according to the American College of Radiology breast imaging reporting and data system lexicon. Strain ratio was obtained using the 1-ROI method (one ROI drawn on the target mass), and the 2-ROI method (one ROI in the target mass and another in reference fat tissue). The diagnostic performance of the three radiologists among datasets and optimal cut-off values for strain ratios were evaluated. Interobserver variability of strain ratio for each ROI method was assessed using intraclass correlation coefficient values, Bland-Altman plots, and coefficients of variation. Results: Compared to US alone, US combined with the strain ratio measured using either ROI method significantly improved specificity, positive predictive value, accuracy, and area under the receiver operating characteristic curve (AUC) (all p values < 0.05). Strain ratio obtained using the 1-ROI method showed higher interobserver agreement between the three radiologists without a significant difference in AUC for differentiating breast cancer when the optimal strain ratio cut-off value was used, compared with the 2-ROI method (AUC: 0.788 vs. 0.783, 0.693 vs. 0.715, and 0.691 vs. 0.686, respectively, all p values > 0.05). Conclusion: Strain ratios obtained using the 1-ROI method showed higher interobserver agreement without a significant difference in AUC, compared to those obtained using the 2-ROI method. Considering that the 1-ROI method can reduce performers' efforts, it could have an important role in improving the diagnostic performance of breast US by enabling consistent management of breast lesions.

Automated Versus Handheld Breast Ultrasound for Evaluating Axillary Lymph Nodes in Patients With Breast Cancer

  • Sun Mi Kim;Mijung Jang;Bo La Yun;Sung Ui Shin;Jiwon Rim;Eunyoung Kang;Eun-Kyu Kim;Hee-Chul Shin;So Yeon Park;Bohyoung Kim
    • Korean Journal of Radiology
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    • v.25 no.2
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    • pp.146-156
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    • 2024
  • Objective: Automated breast ultrasound (ABUS) is a relevant imaging technique for early breast cancer diagnosis and is increasingly being used as a supplementary tool for mammography. This study compared the performance of ABUS and handheld ultrasound (HHUS) in detecting and characterizing the axillary lymph nodes (LNs) in patients with breast cancer. Materials and Methods: We retrospectively reviewed the medical records of women with recently diagnosed early breast cancer (≤ T2) who underwent both ABUS and HHUS examinations for axilla (September 2017-May 2018). ABUS and HHUS findings were compared using pathological outcomes as reference standards. Diagnostic performance in predicting any axillary LN metastasis and heavy nodal-burden metastases (i.e., ≥ 3 LNs) was evaluated. The ABUS-HHUS agreement for visibility and US findings was calculated. Results: The study included 377 women (53.1 ± 11.1 years). Among 385 breast cancers in 377 patients, 101 had axillary LN metastases and 30 had heavy nodal burden metastases. ABUS identified benign-looking or suspicious axillary LNs (average, 1.4 ± 0.8) in 246 axillae (63.9%, 246/385). According to the per-breast analysis, the sensitivity, specificity, positive and negative predictive values, and accuracy of ABUS in predicting axillary LN metastases were 43.6% (44/101), 95.1% (270/284), 75.9% (44/58), 82.6% (270/327), and 81.6% (314/385), respectively. The corresponding results for HHUS were 41.6% (42/101), 95.1% (270/284), 75.0% (42/56), 82.1% (270/329), and 81.0% (312/385), respectively, which were not significantly different from those of ABUS (P ≥ 0.53). The performance results for heavy nodal-burden metastases were 70.0% (21/30), 89.6% (318/355), 36.2% (21/58), 97.3% (318/327), and 88.1% (339/385), respectively, for ABUS and 66.7% (20/30), 89.9% (319/355), 35.7% (20/56), 97.0% (319/329), and 88.1% (339/385), respectively, for HHUS, also not showing significant difference (P ≥ 0.57). The ABUS-HHUS agreement was 95.9% (236/246; Cohen's kappa = 0.883). Conclusion: Although ABUS showed limited sensitivity in diagnosing axillary LN metastasis in early breast cancer, it was still useful as the performance was comparable to that of HHUS.