• Title/Summary/Keyword: Effective core potential

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How to incorporate human failure event recovery into minimal cut set generation stage for efficient probabilistic safety assessments of nuclear power plants

  • Jung, Woo Sik;Park, Seong Kyu;Weglian, John E.;Riley, Jeff
    • Nuclear Engineering and Technology
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    • v.54 no.1
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    • pp.110-116
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    • 2022
  • Human failure event (HFE) dependency analysis is a part of human reliability analysis (HRA). For efficient HFE dependency analysis, a maximum number of minimal cut sets (MCSs) that have HFE combinations are generated from the fault trees for the probabilistic safety assessment (PSA) of nuclear power plants (NPPs). After collecting potential HFE combinations, dependency levels of subsequent HFEs on the preceding HFEs in each MCS are analyzed and assigned as conditional probabilities. Then, HFE recovery is performed to reflect these conditional probabilities in MCSs by modifying MCSs. Inappropriate HFE dependency analysis and HFE recovery might lead to an inaccurate core damage frequency (CDF). Using the above process, HFE recovery is performed on MCSs that are generated with a non-zero truncation limit, where many MCSs that have HFE combinations are truncated. As a result, the resultant CDF might be underestimated. In this paper, a new method is suggested to incorporate HFE recovery into the MCS generation stage. Compared to the current approach with a separate HFE recovery after MCS generation, this new method can (1) reduce the total time and burden for MCS generation and HFE recovery, (2) prevent the truncation of MCSs that have dependent HFEs, and (3) avoid CDF underestimation. This new method is a simple but very effective means of performing MCS generation and HFE recovery simultaneously and improving CDF accuracy. The effectiveness and strength of the new method are clearly demonstrated and discussed with fault trees and HFE combinations that have joint probabilities.

Mobility and productivity: brain circulation and sustainability of the Korean academic system

  • Ki-Seok Kwon;Jeongmin Park;Somin Kim
    • Asian Journal of Innovation and Policy
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    • v.12 no.1
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    • pp.27-53
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    • 2023
  • The purpose of this study is to examine the unique characteristics of the Korean academic system with regard to brain circulation, with a specific emphasis on the influence of overseas-trained academics on research activities within the Korean academic system. We have analyzed the statistical data on individual characteristics and performances of 48,499 Korean academics in science and engineering. We have examined the results at both the system and individual levels within the broader context of the macro characteristics of the Korean academic system. Our analysis reveals that the total number of domestically-trained academics exceeds the number of overseas-trained academics. However, in terms of research funding, overseas-trained academics tend to receive more funding than domestically-trained academics. Furthermore, after controlling other factors such as funding, personal attributes, and environmental factors, our analysis demonstrates that overseas training has a significant and favorable impact on the publication of internationally renowned journals. As such, the presence of overseas returnees has been essential for the effective functioning of the Korean academic system in the global research network and for conducting high-quality academic research. Therefore, the advantages of dependence on scientific core countries such as the US for overseas training have persisted. Nevertheless, upon scrutinizing the group of recently appointed 5,806 academics exclusively, we have discovered that junior academics who received their education domestically exhibit sufficient academic proficiency compared to their colleagues educated overseas. This observation highlights the potential for the Korean academic system to evolve into a self-sustaining system.

Network pharmacology and molecular docking reveal the mechanism of Qinghua Xiaoyong Formula in Crohn's disease

  • Chenyang Fang;Yanni Pei;Yunhua Peng;Hong Lu;Yin Qu;Chunsheng Luo;Yafeng Lu;Wei Yang
    • The Korean Journal of Physiology and Pharmacology
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    • v.27 no.4
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    • pp.365-374
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    • 2023
  • Crohn's disease (CD) is a chronic inflammatory illness of the digestive system with unknown etiology, and its incidence is increasing worldwide. However, there are currently no effective treatments or medications available for individuals with CD. Therefore, novel therapeutic strategies are urgently needed. The bioactive compounds and targets associated with compounds of Qinghua Xiaoyong Formula (QHXYF) were examined using The Traditional Chinese Medicine Systems Pharmacology database, and 5 disease target databases were also used to identify CD-related disease targets. A total of 166 overlapping targets were identified from QHXYF-related and CD-related disease targets and they were found to be enriched in oxidative stress-related pathways and the PI3K/AKT signaling pathway. Molecular docking was then used to predict how the bioactive compounds would bind to the hub targets. It was found that quercetin could be the core bioactive compound and had good binding affinity to the top 5 hub targets. Finally, animal experiments were performed to further validate the findings, and the results revealed that QHXYF or quercetin inhibited 2,4,6-trinitrobenzenesulfonic acid-induced inflammation and oxidative stress processes by inhibiting the PI3K/AKT pathway, thereby improving CD symptoms. These findings suggest that QHXYF and quercetin may be potential novel treatments for CD.

Research on the Development Direction of Language Model-based Generative Artificial Intelligence through Patent Trend Analysis (특허 동향 분석을 통한 언어 모델 기반 생성형 인공지능 발전 방향 연구)

  • Daehee Kim;Jonghyun Lee;Beom-seok Kim;Jinhong Yang
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.16 no.5
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    • pp.279-291
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    • 2023
  • In recent years, language model-based generative AI technologies have made remarkable progress. In particular, it has attracted a lot of attention due to its increasing potential in various fields such as summarization and code writing. As a reflection of this interest, the number of patent applications related to generative AI has been increasing rapidly. In order to understand these trends and develop strategies accordingly, future forecasting is key. Predictions can be used to better understand the future trends in the field of technology and develop more effective strategies. In this paper, we analyzed patents filed to date to identify the direction of development of language model-based generative AI. In particular, we took an in-depth look at research and invention activities in each country, focusing on application trends by year and detailed technology. Through this analysis, we tried to understand the detailed technologies contained in the core patents and predict the future development trends of generative AI.

A Study on the Identifying OECMs in Korea for Achieving the Kunming-Montreal Global Biodiversity Framework - Focusing on the Concept and Experts' Perception - (쿤밍-몬트리올 글로벌 생물다양성 보전목표 성취를 위한 우리나라 OECM 발굴방향 연구 - 개념 고찰 및 전문가 인식을 중심으로 -)

  • Hag-Young Heo;Sun-Joo Park
    • Korean Journal of Environment and Ecology
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    • v.37 no.4
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    • pp.302-314
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    • 2023
  • This study aims to explore the direction for Korea's effective response to Target 3 (30by30), which can be said to be the core of the Kunming-Montreal Global Biodiversity Framework (K-M GBF) of the Convention on Biological Diversity (CBD), to find the direction of systematic OECM (Other Effective area-based Conservation Measures) discovery at the national level through a survey of global conceptual review and expert perception of OECM. This study examined ① the use of Korean terms related to OECM, ② derivation of determining criteria reflecting global standards, ③ deriving types of potential OECM candidates in Korea, and ④ considerations for OECM identification and reporting to explore the direction for identifying systematic, national-level OECM that complies with global standards and reflects the Korean context. First, there was consensus for using Korean terminology that reflects the concept of OECM rather than simple translations, and it was determined that "nature coexistence area" was the most preferred term (12 people) and had the same context as CBD 2050 Vision of "a world of living in harmony with nature." This study suggests utilizing four criteria (1. No protected areas, 2. Geographic boundaries, 3. Governance/management, and 4. Biodiversity value) that reflect OECM's core characteristics in the first-stage selection process, carrying out the consensus-building process (stage 2) with the relevant agencies, and adding two criteria (3-1 Effectiveness and sustainability of governance and management and 4-1 Long-term conservation) and performing the in-depth diagnosis in stage 3 (full assessment for reporting). The 28 types examined in this study were generally compatible with OECMs (4.45-6.21/7 points, mean 5.24). In particular, the "Conservation Properties (6.21 points)" and "Conservation Agreements (6.07 points)", which are controlled by National Nature Trust, are shown to be the most in line with the OECM concept. They were followed by "Buffer zone of World Natural Heritage (5.77 points)", "Temple Forest (5.73 points)", "Green-belt (Restricted development zones, 5.63 points)", "DMZ (5.60 points)", and "Buffer zone of biosphere reserve (5.50 point)" to have high potential. In the case of "Uninhabited Islands under Absolute Conservation", the response that they conformed to the protected areas (5.83/7 points) was higher than the OECM compatibility (5.52/7 points), it is determined that in the future, it would be preferable to promote the listing of absolute unprotected islands in the Korea Database on Protected Areas (KDPA) along with their surrounding waters (1 km). Based on the results of a global OECM standard review and expert perception survey, 10 items were suggested as considerations when identifying OECM in the Korean context. In the future, continuous research is needed to identify the potential OECMs through site-level assessment regarding these considerations and establish an effective in-situ conservation system at the national level by linking existing protected area systems and identified OECMs.

Detection of anomalous features in an earthen dam using inversion of P-wave first-arrival times and surface-wave dispersion curves (P파 초동주시와 표면파 분산곡선 역산을 통한 흙댐의 이상대 탐지)

  • Kim, K.Y.;Jeon, K.M.;Hong, M.H.;Park, Young-Gyu
    • Geophysics and Geophysical Exploration
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    • v.14 no.1
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    • pp.42-49
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    • 2011
  • To locate anomalous features including seepage pathways through the Daeryong earth-fill dam, P and Rayleigh waves were recorded along a 250-m profile on the crest of the dam. Seismic energy was generated using a 5-kg sledgehammer and detected by 24 4.5-Hz vertical-axis geophones installed at 3-m intervals. P-wave and apparent S-wave velocities of the reservoir dam and underlying bedrock were then inverted from first-arrival traveltimes and dispersion curves of Rayleigh waves, respectively. Apparent dynamic Poisson's ratios as high as 0.46 were obtained at the base of the dam near its north-east end, where an outlet conduit occurs, and in the clay core body near the south-west end of the profile where the dam was repeatedly grouted to abate seepage before our survey. These anomalies of higher Poisson's ratios in the upper part of clay core were also associated with effusion of grout on the downstream slope of the dam during post-survey grouting to abate leakage. Combining P-wave traveltime tomography and inversion of Rayleigh wave velocities was very effective in detecting potential pathways for seepage and previous grouted zones in this earthen dam.

Population Size and Home Range Estimates of Domestic Cats (Felis catus) on Mara Islet, Jeju, in the Republic of Korea (제주 마라도에 서식하는 고양이(Felis catus)의 개체군 크기 및 행동권 추정)

  • Kim, Yujin;Lee, Woo-Shin;Choi, Chang-Yong
    • Korean Journal of Environment and Ecology
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    • v.34 no.1
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    • pp.9-17
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    • 2020
  • Domestic cats (Felis catus) introduced to insular environments can be invasive predators that often threaten endemic species and cause biodiversity loss or local extinction on the island. This study was conducted from March to July 2018 to understand the population size, home range, and spatial use of cats introduced to Mara Islet (N 33° 07', E 126° 16') in Jeju Special Governing Province, the Republic of Korea. Observation records based on their natural marks revealed that there were 20 adult cats on Mara Islet. A capture-recapture method also estimated 20 adult individuals (95% confidence interval: 20-24 individuals). According to our telemetry study on ten adults deployed with GPS-based telemetry units, the home range size was 12.05±6.99 ha (95% KDE: kernel density estimation), and the core habitat size was 1.60±0.77 ha (50% KDE). There were no significant differences in the home range and core habitat sizes by sex. The home range of domestic cats overlapped with the human residential area, where they might secure easy foods. Five of ten tracked cats were active at potential breeding colonies for the Crested Murrlet (Synthliboramphus wumizusume), and six approached potential breeding areas of the Styan's Grasshopper Warbler (Locustella pleskei), suggesting the predation risk of the two endangered species by cats. This study provides novel information on the population size and home range of introduced cats on Mara Islet which is an important stopover site of migratory birds as well as a breeding habitat of the two endangered avian species. Reducing the potential negative impacts of the introduced cats on migratory birds and the endangered species on Mara Islet requires monitoring of the predation rate of birds by cats, the population trends of cats and endangered breeding birds as well as the effective cat population control and management.

A Study on the Standardization of Education Modules for ARPA/Radar Simulation (ARPA/레이더 시뮬레이션 교육 모듈의 표준화 연구)

  • Park, Young-Soo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.22 no.6
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    • pp.631-638
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    • 2016
  • A mariner cadet gains the ability to identify and avoid potential collisions with other ships through ARPA/Radar simulation education. This research surveyed first domestic and overseas's rules (e.g., MOMAF's Standard, the STCW Convention, etc.) of the simulation education, upon investigation the only content and timing of this simulation-based education are specified according to these rules, and maritime education institutions issue the related certification autonomously after a student has taken the simulation because no simulation education module exists to further guide the ARPA/Radar simulation. As a result, it is difficult for students to acquire consistent maritime ability through ARPA/Radar simulation. This paper discusses standardization of these education modules to produce more consistent mariner ability, and verify the degree of improvement of education that would be achieved by enacting the proposed education module. The simulation education system used in maritime institutions in Korea was investigated, and scenarios reflecting traffic flow in actual waterways was proposed based on marine traffic surveys so teaching modules can educate/assess more effectively based on core marine abilities. Improvements in education and training were also verified using data collected over 2 years based on a standardized module. Each education institution can enact an effective, systematic education approach using standardized ARPA/Radar education modules proposed in this paper, and this can set a foundation to contribute to safer vessel navigation by improving maritime abilities.

The Independent Living of People with Developmental Disabilities and Supported Living Model - The Implication for Social Welfare for People with Disabilities - (지원생활모델(Supported Living model)을 적용한 발달장애인의 자립 - 한국 장애인복지에의 함의 -)

  • Kim, Mi Ok;Jung, Min Ah
    • Korean Journal of Social Welfare
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    • v.69 no.1
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    • pp.255-281
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    • 2017
  • This study aimed to introduce the main concepts of Supported Living(SL) model, very few of which have discussed in the context of S. Korea, explore the potential to employ SL model, and draw the implication for social welfare for people with developmental disabilities(DD) in S. Korea. For this purpose, this study presented the developmental background, main concepts, and principles of SL model, compared SL with supported housing and explained the features of SL model. Additionally, this study reviewed SL schemes in the UK and Australia to understand how SL schemes impact the lives of people with DD. Furthermore, this study addressed the contents of SL manuals used in the UK and Australia and identified the core aspects of SL practice. Based on the findings, this study highlighted the importance of SL as the conceptual model for independent living of people with DD and discussed the implication of SL model in S. Korea in terms of the national institution for people with DD, service agencies, and service users. This study focused on the SL model as a conceptual model for the independence of people with DD, potentials to employ SL model, and its implication for social welfare for people with disabilities in S. Korea. SL model and its application showed that SL model is effective and flexible in supporting the independent living of people with DD. Findings and implications regarding SL model could be the basis for the development of the Korean supported living system to improve the independent living of people with DD.

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Biological Control of Mycophila speyeri Barnes (Diptera: Cecidomyiidae) using Korean Steinernema and Heterorhabditis Isolates in Pleurotus ostreatus Cultivation House (느타리버섯 재배사에서 한국산 Steinernema와 Heterorhabditis를 이용한 버섯혹파리(Mycophila speyeri)의 생물적 방제)

  • Kim Hyeong Hwan;Choo Ho Yul;Lee Dong Won;Lee Heung Su;Jeon Heung Yong;Ha Pan Jung
    • Korean journal of applied entomology
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    • v.43 no.3 s.136
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    • pp.233-239
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    • 2004
  • The potential of five entomopathogenic nematodes, Steinernema carpocapsae Pocheon strain, S. logicaudum Nonsan strain, S. glaseri Dongrae strain, Heterorhabditis bacteriophora Hamnyang strain, and Heterorabditis sp. Gyeongsan strain were evaluated as biological control agents against a mushroom fly, Mycophila speyeri in the mushroom, Pleurotus ostreatus cultivation house. Control effect of M. speyeri was significantly different according to nematode species. Heterorhabditis was more effective than Steinernema. H. bacteriophora Hamnyang strain showed the highest control effect representing $49.0\%$ (7 days), $89.5\%$ (14 days) and $89.1\%$ (21 days post-treatment) at the rate of $1\times10^6$ and $46.5\%$ (7 days), $76.6\%$ (14 days) and $85.4\%$ (21 days post-treatment) at the rate of $1.0\times10^5$ Ijs/$1.5 m^2$ in Changnyoung, Gyeongnam, respectively. In Jinju, Gyeongnam, control effects of the sa me species were $54.0\%$ (7 days), $74.5\%$ (14 days), and $79.8\%$ (21 days post-treatment) at the rate of $1\times10^6$ and $49.0\%$ (7 days), $76.6\%$ (14 days), and $61.1\%$ (21 days post-treatment) at the rate of $1.0\times10^5$ Ijs/$1.5 m^2$, respectively.