• The Journal of Asian Finance, Economics and Business
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• v.8 no.12
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• pp.261-269
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• 2021

This study examines the effect of block diversity on the risk of firms listed on the Korean Stock Exchange between 2010 and 2017. To examine the effect of block diversity on corporate risk, we measure block diversity in terms of a single component, portfolio size, by referring to prior literature. This diversity component accounts for the differences in portfolio size across corporate blocks. In line with existing research on corporate risk, we consider several variables to measure corporate risk: volatility, beta, and idiosyncratic risk. The results show a negative relationship between the size of a block shareholder's portfolio and corporate risk. We also show no difference in the effect of block diversity on the corporate risk between KOSPI and KOSDAQ. This implies that the difference in portfolio size among corporate blocks reduces corporate risk. This may be due to the effect of inter-block monitoring activities in the Korean securities market, which benefits from block diversity. This empirical result supports previous studies that predicted that block diversity would have beneficial influences on firm monitoring in general. This study is significant in that it analyzes the relationship between block diversity and firm risk and provides relevant information to business practitioners and investors.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2004.05a
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• pp.47-60
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• 2004

Higher plants can be valuable genetic assay systems for monitoring environmental pollutants and evaluating their biological toxicity. Two assays are considered ideal for in situ monitoring and testing of soil, airborne and aqueous mutagenic agents; the Tradescantia stamen hair assay for somatic cell mutations and the Tradescantia micronucleus assay for chromosome aberrations. Both assays can be used for in vivo and in vitro testing of mutagens. Since higher plant systems are now recognized as excellent indicators and have unique advantages over in situ monitoring and screening, higher plant systems could be accepted by regulatory authorities as an alternative first-tier assay system for the detection of possible genetic damages resulting from the pollutants or chemicals used and produced by industrial sectors. It has been concluded that potential mutagen and carcinogen such as the heavy metals among indoor air particulates, volatile compounds in the working places, soil, and water pollutants contribute to the overall health risk. This contribution can be considerable under certain circumstances. It is therefore important to identify the level of genotoxic activity in the environment and to relate it to the biomarkers of a health risk in humans. The results from the higher plant bioassays could make a significant contribution to assessing the risks of pollutants and protecting the public from agents that can cause mutation and/or cancer. The plant bioassays, which are relatively inexpensive and easy to handle, are recommended for the scientists who are interested in monitoring pollutants and evaluating their environmental toxicity to living organisms.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.05a
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• pp.1-15
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• 2004

Higher plants can be valuable genetic assay systems for monitoring environmental pollutants and evaluating their biological toxicity. Two assays are considered ideal for in situ monitoring and testing of soil, airborne and aqueous mutagenic agents; the Tradescantia stamen hair assay for somatic cell mutations and the Tradescantia micronucleus assay for chromosome aberrations. Both assays can be used for in vivo and in vitro testing of mutagens. Since higher plant systems are now recognized as excellent indicators and have unique advantages over in situ monitoring and screening, higher plant systems could be accepted by regulatory authorities as an alternative first-tier assay system for the detection of possible genetic damages resulting from the pollutants or chemicals used and produced by industrial sectors. It has been concluded that potential mutagen and carcinogen such as the heavy metals among indoor air particulates, volatile compounds in the working places, soil, and water pollutants contribute to the overall health risk. This contribution can be considerable under certain circumstances. It is therefore important to identify the level of genotoxic activity in the environment and to relate it to the biomarkers of a health risk in humans. The results from the higher plant bioassays could make a significant contribution to assessing the risks of pollutants and protecting the public firom agents that can cause mutation anuor cancer. The plant bioassays, which are relatively inexpensive and easy to handle, are recommended for the scientists who are interested in monitoring pollutants and evaluating their environmental toxicity to living organisms.

• Korean Journal of Transplantation
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• v.32 no.4
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• pp.75-83
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• 2018

Background: This study was designed to analyze the clinical usefulness of mycophenolic acid trough concentration monitoring in kidney transplantation patients who were maintained with cyclosporine. Methods: The data of patients who underwent mycophenolic acid trough concentration monitoring after their first kidney transplant between November 2006 and August 2013 and were prescribed with cyclosporine, mycophenolate, and methylprednisolone were reviewed retrospectively. Cox analysis was used to analyze the risk factors for acute rejection within 1 year post-transplantation. Results: Among 90 patients, 41 (45.6%) achieved both the target levels of cyclosporine and mycophenolic acid, while three patients (3.3%) failed to achieve the target level of either cyclosporine or mycophenolic acid. Nine patients (10.0%) only achieved the mycophenolic acid target level and 37 patients (41.1%) only achieved the cyclosporine target level. While patients who achieved only the mycophenolic acid target concentration had no statistically increased risk compared to patients who achieved both target levels (hazard ratio [HR], 1.569; 95% confidence interval [CI], 0.316 to 7.778; P=0.581), patients who only achieved the cyclosporine target concentration showed an increased risk of rejection compared to the both achievement group (HR, 4.112; 95% CI, 1.583 to 10.683; P=0.004). Patients who had no achievement in the target levels showed significantly increased rejection risk compared to the patients who achieved both target levels (HR, 17.811; 95% CI, 3.072 to 103.28; P=0.001). Conclusions: Mycophenolic acid trough concentration monitoring combined with cyclosporine trough concentration monitoring is useful for avoiding acute cellular rejection if the first 1 year post-transplantation.

• Journal of the Semiconductor & Display Technology
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• v.12 no.2
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• pp.73-78
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• 2013

This paper proposes a portable electrocardiograph and smart device-based heart health monitoring and risk notification system. The proposed system consists of a portable electrocardiograph and a smart device for a system user, and a web-based monitoring system for observers. This system can improve the convenience and efficiency of measurement by using a light-weight portable electrocardiograph and a smart device. In addition, any authorized person such as caregiver or family member who is not related to medical institution can monitor users'heart health in real-time using the web-based monitoring system. Therefore, a user and authorized remote observers can efficiently monitor and manage user's heart health in daily-life even without any medical institution's help, and can preemptively deal with any possible dangerous situations, such as degeneration of a cardiac disorder and sudden cardiac death.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.101-102
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• 2022

The current facility condition monitoring has disadvantages such as a slow inspection cycle, a risk of human casualties, and the need for a lot of time and money as the size of the structure is larger, because human access is required with limited use. Drones can reduce the risk of human casualties due to their good accessibility, and can compensate for the shortcomings of the current method by enabling monitoring on a wide scale. The goal of this study is to provide the current domestic monitoring process through benchmarking according to the recent research case of the US Department of Transportation (DOT) to suggest a process suitable for the domestic situation and the direction of future improvement measures.

• Journal of Environmental Health Sciences
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• v.47 no.4
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• pp.356-365
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• 2021

Background: Concerns have been raised regarding the criteria of groundwater, in particular in Gwangwon-do Province where many residents drink groundwater due to the poor supply of tap water and a high nonconformity rate with water quality criteria nationwide. Objectives: Water quality monitoring and risk assessment were conducted for groundwater in Hoengseong, Gangwon-do Province. Methods: A total of 46 items required for meeting drinking water criteria were analyzed from 258 samples collected from March 2017 through August 2018 (152 sites in 2017 and 106 sites in 2018). Risk assessment was conducted for two non-carcinogens (F^- and NO₃-N), and one carcinogen (i.e., arsenic) based on their high nonconformity to water quality criteria. Results: Water quality analysis revealed that the total proportion of nonconformities was determined to be 27.9%. The nonconformity rate for each content item is as follows: total colony counts (1.6%), total coliform (6.2%), Escherichia coli (1.2%), F^- (8.1%), arsenic (4.7%), NO₃-N (8.1%), pH (1.2%), manganese (0.4%), and turbidity (5.8%). Risk assessment indicated that fluoride induced a hazard quotient greater than 1 with the 95% UCL (Upper Confidence Limit) concentration of the total 258 sites and average, median, and 95% UCL concentrations of nonconformity sites. For NO₃-N, there was no human health risk. For arsenic, the excess cancer risk exceeded the acceptable cancer risk of 1×10^-6 with the average and 95% UCL concentrations of total 258 sites and average, median, and 95% UCL concentrations of nonconformity sites. Conclusions: This study suggests that it is necessary to expand water quality monitoring of groundwater and conduct a more detailed risk assessment in order to establish a health care plan for the residents of Hoengseong, Gangwon-do Province.

• IE interfaces
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• v.17 no.1
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• pp.13-21
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• 2004

In this study, the prototype of a system for checking risk-factor of NC machine is proposed. The proposed system can get the risk-related information by monitoring the status of real-time processes of NC machines. Using the information, the accidents can be prevented by the background process of an expert system tool. This paper consists of 2 parts: (1) the method for gathering data and definition of the risk-related factors of NC machines and (2) the procedure for finding the proper actions by using the forward chaining of a rule-base. Proposed system is implemented with C++ language under MS-windows.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.493-495
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• 2016

The framework and application model for risk mitigation service based on network provides monitoring function of the risk event data to be inputted and analyses it for mitigation process. Furthermore, it performs the analysis of the manmade calamities such as accident, building destruction, natural calamities caused by climate change, and animal harms caused by bird flu and foot-and-mouth disease occurring in livestock and wild animals, and provides the mitigation service of it. The application model for risk mitigation is combined with network and carries out the real time acquisition and monitoring of risk events, and provides mitigation service for the risks caused by calamities and reduces economic losses.

• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.103-110
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• 2021

In the development of a Risk Monitor probabilistic safety assessment (PSA) model from the basic PSA model of a nuclear power plant, the modeling of common-cause failure (CCF) is very important. At present, some approximate modeling methods are widely used, but there lacks criterion of modeling accuracy and error analysis. In this paper, aiming at ensuring the accuracy of risk assessment and minimizing the Risk Monitor PSA models size, we present three basic issues of CCF model resulted from the changes of a nuclear power plant configuration, put forward corresponding modeling methods, and derive accuracy criteria of CCF modeling based on minimum cut sets and risk indicators according to the requirements of risk monitoring. Finally, a nuclear power plant Risk Monitor PSA model is taken as an example to demonstrate the effectiveness of the proposed modeling method and accuracy criteria, and the application scope of the idea of this paper is also discussed.