• Title/Summary/Keyword: field investigation

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Correction of the Ground Subsidence Risk Ratings during Open Cut Excavation (개착식 굴착공사 중 지반함몰 위험등급 분류시트의 등급 보정에 관한 연구)

  • Shin, Sang-Sik;Kim, Hak Joon
    • The Journal of Engineering Geology
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    • v.31 no.2
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    • pp.135-148
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    • 2021
  • Ground subsidence risk ratings obtained from the site investigation during pre-excavation stages could be changed depending on the parameters revealed during construction activities. A method of correcting the pre-excavation ground subsidence risk ratings based on the site conditions observed in the field is suggested in this study. The elevation of groundwater table during the excavation may be different from the predicted value depending on the application of waterproofing methods and construction conditions. The drastic drawdown of groundwater table during the excavation could cause ground subsidence due to soil volume decrease related to consolidation or compression of the ground, whereas the rising of groundwater table caused by the intense rainfall may result in a high potential for ground subsidence due to heaving or boiling of the excavation bottom. Excessive displacements of retaining walls or ground settlements may cause ground subsidence, which also results in a high risk of ground subsidence caused by the destruction of buried pipelines. Reevaluation of ground subsidence risk ratings is suggested considering the fluctuation of groundwater table, condition of groundwater leakage, measured ground displacements, and soil types. Finally, the ground subsidence risk rating system is improved for better evaluation by using 12 factors in 5 categories.

Research on Intelligent Space Design of smart rural - Focus on Xikou village, Zhejiang Province, China (스마트 향촌을 위한 지능형 공간 디자인 연구 - 중국 저장성 시커우촌을 중심으로)

  • Zhu, Miaomiao;Jang, Wan-Sok;Pan, Young-Hwan
    • Journal of the Korea Convergence Society
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    • v.13 no.4
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    • pp.245-259
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    • 2022
  • Smart rural construction is an important direction for the Chinese government to promote the cause of "Rural Revitalization". In this paper, in the Xikou village project of the "future community" smart rural demonstration development project proposed by the local government of Zhejiang Province, China, the researcher participated in the design of the intellectualization of the smart rural life circle from the perspective of UX design and through qualitative and quantitative research methods. Through field investigation, understand the users' needs for intelligent design of smart countryside, and on this basis, design the maximum space of the region as a cognitive smart rural demonstration park, and quantitatively analyze the user experience feedback after the completion of the project. Before and after the actual design and application of the "Xikou village" in the demonstration area, chapters 3 and 4 are the symbols that can remember the rural era, the Rural Cultural Exchange Square. In the intelligent office space and living space, the user needs are composed of the design results. In order to reduce the anxiety of residents and tourists caused by the intelligent environment, the artificial manual service part is also designed. Now, as a case of intelligent rural space design, resident residence is developing continuously.

Investigation of the Ptimum Transplanting Date for Floury Endosperm Rice to Reduce the Viviparity Rate (쌀가루 가공용 벼 품종의 수발아 발생 감소를 위한 적합 이앙시기 설정)

  • Hwang, Woon-Ha;Choi, Meong-Gue;Jeong, Jae-Hyeok;Lee, Hyen-Seok;Yang, Seo-Yeong;Lee, Chung-gun
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.66 no.4
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    • pp.289-296
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    • 2021
  • This study aimed to analyze the optimal transplanting date of the floury endosperm rice varieties Hangaru, Seolgeang, Singil, and Baromi2 allowing to reduce the viviparity rate. The viviparity rate rapidly increased with the mean temperature during the ripening stage. Therefore, to reduce the viviparity rate, we calculated the optimum heading date based on the safe heading date limit in each area so that the ripening stage occurred at lower temperatures. hen, the effects of changes in heading date were monitored by recording the transplanting date and the temperature during the growth period. The transplanting date was highly correlated with the number of heading days in the field. Therefore, the optimum transplanting date was calculated according to the transplanting date in each area. When the accumulated temperature was 700℃, if floury rice was transplanted at the optimum transplanting date, the mean temperature was approximately 20℃. When the accumulated temperature was 900℃, the mean temperature was approximately 18℃. Under these conditions, the viviparity rates of Hangaru, Seolgeang, and Singil rice were lower than 10%. However, Baromi2 showed a high viviparity rate. These results suggest that the viviparity rate of Hangaru, Seolgeang, and Singil rice can be reduced by transplanting at the optimum transplanting date. However, further research is required for pinpointing the optimum transplanting date of Baromi2 rice.

Investigation of the change in physical habitat in the Geum-gang River by modifying dam operations to natural flow regime (자연유황 회복을 위한 댐 운영에 따른 금강의 물리서식처 변화 분석)

  • Choi, Byungwoong;Jang, Jiyeon;Choi, Sung-Uk
    • Journal of Korea Water Resources Association
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    • v.54 no.11
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    • pp.985-998
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    • 2021
  • In general, the upstream dam changes downstream flow regime dramatically, i.e., from natural flow regime to hydropeaking flows. This study investigates the impact of the natural flow pattern on downstream fish habitat in a regulated river in Korea using the physical habitat simulation. The study area is a 13.4 km long reach of the Geum-gang River, located downstream from the Yongdam Dam, Korea. A field monitoring revealed that three fish species are dominant, namely Zacco platypus, Coreoleuciscus splendidus, and Opsariichthys bidens, and they account for 70% of the total fish community. Specially, Opsariichthys bidens is an indigenous species in the Geum-gang River. The three fish species are selected as target fish species for the physical habitat simulation. The Nays2D model, a 2D shallow water equation solver, and the HSI (Habitat Suitability Index) model are used for hydraulic and habitat simulations, respectively. To assess the impact of the natural flow pattern, this study uses the annual natural flow regime and hydropeaking flows from the dam. It is found that the natural flow regime increases significantly the Composite Suitability Index (CSI) in the study reach. Then, using the Building Block Approach (BBA), the scenarios for the modifying dam operations are presented in the study reach. Both Scenario 1 and scenario 2 are proposed by using the hydrological method considering both magnitude and duration of the inflow and averaging the inflow over each month, respectively. It is revealed that the natural flow regime embodied in scenario 1 and scenario 2 increases the Weighted Usable Area (WUA) significantly, compared to the hydropeaking flows. In conclusion, the modifying the dam operations by restoring to the natural flow pattern is advantageous to fish community.

Research Trends in Induced Polarization Exploration in Korea (국내 유도분극 탐사의 연구동향)

  • Park, Samgyu
    • Geophysics and Geophysical Exploration
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    • v.24 no.4
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    • pp.202-208
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    • 2021
  • Induced polarization (IP) was first published in a Korean academic journal in 1973, and it was soon applied to coal and metal ore exploration. Then, in universities and research institutes, IP modeling studies using the finite element approach and experimental studies on IP responses for artificial samples were conducted. In the mid-1980s, the spectral IP (SIP) measurement module was introduced to Korea, and physical scale modeling and inversion approaches were developed. Due to the decline of the mineral resource industry, this method was not actively applied. However, the SIP method was not applied In the 1990s, IP exploration was applied in the investigation of hydrothermal deposits of sulfide minerals and bentonite mineralization zones, as well as to areas where the groundwater was contaminated by intruding seawater. In the 2000s, three-dimensional inversion of the IP approach was developed, and high-precision geophysical exploration was required to secure domestic and overseas mineral resources, so SIP experiments on rock samples and approaches for field exploration were developed. The SIP approach was proven useful for the exploration of metal deposits containing sulfide minerals by applying it to explore the mineralization zone of gold-silver deposits in the Haenam region. The IP method is considered to be effective in exploring critical minerals (lithium, cobalt, and nickel) in high-tech industries. It also is expected to be useful for environmental and geotechnical investigations.

A Study on Factors Affecting the Reuse of Research Data by Academic Researchers in the Social Sciences (사회과학분야 학술 연구자의 연구데이터 재이용 영향요인 연구)

  • Bak, Ji Won;Chang, Woo Kwon
    • Journal of the Korean Society for information Management
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    • v.38 no.4
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    • pp.199-230
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    • 2021
  • This study is to present an analysis and activation plan for the effect of reuse of research data through investigation of researchers and reuse data on reuse of research data. To this end, 178 copies were analyzed based on the distribution and collection of surveys targeting academic researchers in the field of social science in Korea who have experience in calculating new research results by reusing research data. As a result, 1) Most researchers acquire reuse data through systems such as data repositories, data management systems, and research data DBs, and mainly reuse analysis data produced through experiments and observations. In addition, despite being a researcher who successfully reused research data, the awareness of research data sharing was low and did not share it in the face of various problems. 2) The reliability and validity of 10 factors derived through literature review and factor analysis (academic usefulness, research efficiency, researcher concerns, data vulnerability, direct effort, indirect effort, suitability for reuse, data completeness, data usefulness, and social conditions) were verified. 3) As a result of correlation analysis, research efficiency, social conditions showed a quantitative correlation with research data reuse intention, researcher concerns, data vulnerability, and direct effort showed a negative correlation with research data reuse intention. As a result of regression analysis, all of these factors had a significant effect on the intention to reuse research data, and in the order of research efficiency, social conditions, direct efforts, researchers' concerns, and data vulnerability. Based on this, a plan to revitalize the reuse of research data was proposed.

A Comparative Analysis of Keywords in Astronomical Journals and Concepts in Secondary School Astronomy Curriculum (최근 천문학 연구 키워드와 천체 분야 교육과정 내용 요소 비교 분석)

  • Shin, Hyeonjeong;Kwon, Woojin;Ga, Seok-Hyun
    • Journal of The Korean Association For Science Education
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    • v.42 no.2
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    • pp.289-309
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    • 2022
  • In recent years, astronomy has been snowballing: including Higgs particle discovery, black hole imaging, extraterrestrial exploration, and deep space observation. Students are also largely interested in astronomy. The purpose of this study is to discover what needs to be improved in the current astronomy curriculum in light of recent scientists' researches and discoveries. We collected keywords from all papers published from 2011 to 2020 in four selected journals-ApJ, ApJL, A&A, and MNRAS- by R package to examine research trends. The curriculum contents were extracted by synthesizing the in-service teachers' coding results in the 2015 revised curriculum document of six subjects (Science, Integrated Science, Earth Science I, Earth Science II, Physics II, Convergence Science). The research results are as follows: first, keywords that appear steadily in astronomy are 'galaxies: formation, galaxy: active, star: formation, accretion, method: numerical.' Second, astronomy curriculum includes all areas except the 'High Energy Astrophysical Phenomena' area within the common science curriculum learned by all students. Third, it is necessary to review the placement of content elements by subject and grade and to consider introducing new concepts based on astronomy research keywords. This is an exploratory study to compare curriculum and the field of scientific research that forms the basis of the subject. We expect to provide implications for a future revision of the astronomy curriculum as a primary ground investigation.

Progressive Collapse Resistance Analysis of Precast Concrete Building Structures in Korea (국내 프리캐스트 콘크리트 건축구조물의 연쇄붕괴저항 성능분석)

  • Kim, Sung-Hyun;Kang, Joon-Hee;Hwang, Hyeon-Jong;Choi, Ha-Jin;Kang, Su-Min
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.34 no.6
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    • pp.417-426
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    • 2021
  • Recently, use of the precast concrete (PC) system, which can increase economy by minimizing field work, has rapidly increased. However, the PC system cannot exhibit structural performance under construction, specifically before integration between members. Furthermore, since it is difficult to secure the structural integrity of beam-column joints even after construction, the PC system is vulnerable to progressive collapse. In the PC system, various types of details for PC beam-column joints have been proposed, while the structural/construction details of PC system generally used in Korea differ from those of overseas PC systems. However, studies on the progressive collapse of the domestic PC system are limited. Thus, in this study, we investigated the structural/construction details of PC beam-column joints mainly used in Korea. Based on the investigation, for the prototype PC system with typical joint details, a nonlinear finite element analysis was carried out to evaluate its structural performance under progressive collapse. Further, a parametric study was performed, and the effect of the design parameters was investigated, to recommend a method to improve the progressive collapse resistance of the PC system.

Interest in Health and Hygiene of Hairdressers and Their Awareness of COVID-19 (헤어 미용인들의 보건위생 관심과 COVID-19에 대한 인식정도 연구)

  • Shim, Sang Hee;Lee, Keun Kwang
    • Journal of Naturopathy
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    • v.10 no.2
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    • pp.93-107
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    • 2021
  • Background: The need for an investigation into the hygiene and awareness of hairdressers regarding Corona infection has emerged. Purpose: To investigate the level of interest in health and hygiene of hairdressers and their awareness of COVID-19. Methods: A questionnaire survey was conducted with hairdressers located in Daejeon Metropolitan City. The SPSS 26.0 program analyzed a total of 260 collected questionnaires. Results: The interest in the health and hygiene of hairdressers showed a statistically significant difference according to age, educational background, job title, type of hairdresser, and years of service. The hairdresser's risk and degree of awareness of COVID-19 were higher in those in their 30s or older, managers, medium-sized stores, and ten years of service. In terms of optimism about Corona, it was found to be high among those in their 20s, assistant staff, large stores, and less than five years of service. In addition, there was a positive (+) correlation between health care concerns, hand hygiene and mask hygiene, and awareness of corona risk and optimism. Conclusions: The level of health and hygiene interest and awareness of hairdressers significantly increased according to age, educational background, job title, type of hairdresser, and length of service. Therefore, it evaluated that this result would serve as primary data for research in this field.

Analysis of Research Trends in Tax Compliance using Topic Modeling (토픽모델링을 활용한 조세순응 연구 동향 분석)

  • Kang, Min-Jo;Baek, Pyoung-Gu
    • The Journal of the Korea Contents Association
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    • v.22 no.1
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    • pp.99-115
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    • 2022
  • In this study, domestic academic journal papers on tax compliance, tax consciousness, and faithful tax payment (hereinafter referred to as "tax compliance") were comprehensively analyzed from an interdisciplinary perspective as a representative research topic in the field of tax science. To achieve the research purpose, topic modeling technique was applied as part of text mining. In the flow of data collection-keyword preprocessing-topic model analysis, potential research topics were presented from tax compliance related keywords registered by the researcher in a total of 347 papers. The results of this study can be summarized as follows. First, in the keyword analysis, keywords such as tax investigation, tax avoidance, and honest tax reporting system were included in the top 5 keywords based on simple term-frequency, and in the TF-IDF value considering the relative importance of keywords, they were also included in the top 5 keywords. On the other hand, the keyword, tax evasion, was included in the top keyword based on the TF-IDF value, whereas it was not highlighted in the simple term-frequency. Second, eight potential research topics were derived through topic modeling. The topics covered are (1) tax fairness and suppression of tax offenses, (2) the ideology of the tax law and the validity of tax policies, (3) the principle of substance over form and guarantee of tax receivables (4) tax compliance costs and tax administration services, (5) the tax returns self- assessment system and tax experts, (6) tax climate and strategic tax behavior, (7) multifaceted tax behavior and differential compliance intentions, (8) tax information system and tax resource management. The research comprehensively looked at the various perspectives on the tax compliance from an interdisciplinary perspective, thereby comprehensively grasping past research trends on tax compliance and suggesting the direction of future research.