• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.4
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• pp.821-825
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• 2007

In this study, the single hardening model with stress history-dependent plastic potential, which has been most recently proposed based on the critical state soil mechanics and needs few model parameters, was verified for the normally, lightly, and heavily over-consolidated clayey specimens. The triaxial compression tests were strictly conducted. The predictions using the single hardening model generally agree with the measurement. The discrepancy exists on its main focusing on the principal stress rotation; however, the plastic work H and the principal stress rotation angle ${\beta}$ are found to be effective indicators of loading history for the plastic potential function of the stress path dependent materials.

• Bulletin of the Korean Chemical Society
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• v.21 no.11
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• pp.1133-1137
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• 2000

Gibbs ensemble Monte Carlo simulations were performed to calculate the vapor- liquid coexistence properties for the binary mixtures $CO_2/C_3H8$, $CO_2/CH_3OCH_3$, and $CO_2/CH_3COCH_3.$ For all the molecules the potential between sites in different molecules was simply calculated by the Lennard-Jones potential. Density of the mixture, composition of the mixture, the pressure-composition diagram, the chemical potential of component, and the radial distribution function were calculated at vapor- liquid equilibrium. The composition and the density of both vapor and liquid from simulation agreed considerably well with the experimental values over a wide range of pressures. The radial distribution functions in the liquid mixtures showed that $CO_2$ molecules tended to form cluster with each other and $C_3H8$ molecules also aggregated each other due to the weak interaction between $CO_3$ and $C_3H8$ molecule. However the interaction potentials between the same components were similar to those between the different components in the liquid mixtures $CO_2/CH_3OCH_3$ and $CO_2/CH_3COCH_3$.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.218-218
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• 2019

Jeju island has an area of $1,810km^2$ and is considered the largest island in South Korea. In Jeju Island the average annual precipitation is 1,957mm. About 54% of precipitation is estimated to be lost due to evapo-transpiration and direct runoff, and the remainder is recharged. Historically springs and puddles were the island's primary sources of water. However, after 1970 all sectors, including the urban and industrial sectors depended solely on groundwater as their water resource. As vast amount of water is being recharged the Island has many springs, especially near the coastlines. Historlcally, spring of Jeju Island formed village and make it possible to continue a life. Also it produces many values such as the spring related story, culture, tourism and ecosystems. Especially, the naturally rare phenomenon that about 900 springs appear over the whole area of Jeju Island makes it possible to call it as a natural heritage. As a result of this most springs have either been destroyed or been in the state of neglect. In some cases it has been observed that springs were preserved by nature, however majority of the cases saw springs losing their own nature as a result of abandonment. It was recorded that there were 911 springs in Jeju Island with most of them being distributed along the coast, which consequently increases their susceptibility to seawater intrusion. The objective of this study is therefore to analyze Eco-cultural and Engineering characteristics about springs in the island, highlighting its past utilization and reestablishing its potential as a source of spring.

• The Plant Pathology Journal
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• v.39 no.5
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• pp.504-512
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• 2023

After transitioning from periodic to model-based control policy for fire blight blossom infection, it is crucial to provide the timing of field application with easy and accurate information. To assess the risk of blossom infection, Maryblyt was employed in 31 sites across apple-producing regions nationwide, including areas prone to fire blight outbreaks, from 2021 to 2023. In 2021 and 2023, two and seven sites experienced Blossom Infection Risk-Infection warning occurrences among 31 sites, respectively. However, in 2022, most of the sites observed Blossom Infection Risk-Infection from April 25 to 28, highlighting the need for blossom infection control. For the comparison between the two model-based control approaches, we established treatment 1, which involved control measures according to the Blossom Infection Risk-Infection warning and treatment 2, aimed at maintaining the Epiphytic Infection Potential below 100. The analysis of control values between these treatments revealed that treatment 2 was more effective in reducing Blossom Infection Risk-Infection and the number of days with Epiphytic Infection Potential above 100, with respective averages of 95.6% and 93.0% over the three years. Since 2022, the implementation of the K-Maryblyt system and the deployment of Automated Weather Stations capable of measuring orchard weather conditions, with an average of 10 stations per major apple fire blight county nationwide, have taken place. These advancements will enable the provision of more accurate and timely information for farmers based on fire blight models in the future.

• Natural Product Sciences
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• v.29 no.2
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• pp.67-73
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• 2023

Oxidative stress brings about apoptosis through various mechanisms. In particular, oxidative stress in neuronal cells can causes a variety of brain diseases. This study was conducted to investigate the effect of Bidens tripartita on oxidative stress in neuronal cells. B. tripartita has traditionally been used in Russia as a medicine for diseases such as rhinitis, angina and colitis. Over-production of glutamate induces oxidative stress. When the oxidative stress occurs in the cells, reactive oxygen species (ROS) and Ca²⁺ increase. In addition, the abrupt decline of mitochondrial membrane potential and the decrease of glutathione related enzymes such as glutathione reductase (GR) and glutathione peroxidase (GPx) are also observed. The samples used in the experiment showed cytoprotective effect in the MTT assay. It also lowered the ROS and Ca²⁺ level, and increased degree of mitochondrial membrane potential, GR and GPx. As a result, B. tripartita had a positive effect against oxidative stress. Thus, it is expected to have potential for treatment and prevention of degenerative brain diseases such as Alzheimer's disease.

• International conference on construction engineering and project management
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• 2020.12a
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• pp.103-113
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• 2020

The construction industry is undergoing a digital transformation in which Building Information Modelling (BIM) is a key technology. The potential of BIM in several areas such as design optimization, time management, cost management, and asset management/facility management (AM/FM) is widely acknowledged by the AECO (Architecture, Engineering, Construction, and Operation) industry around the world. However, BIM implementation in construction projects is faced with problems such as project delay and cost overruns. The lack of identification of risks in BIM projects and standard guidelines on mitigation techniques furthers poor performance, dissatisfaction, and disputes between employers and project participants, which results in low BIM adoption rates. Therefore, the objective of this paper is to identify the potential risks in BIM implementation under the primary categories - (1) technical, (2) contractual, (3) management-related, and (4) personnel-related risks in BIM projects and present solutions to reduce, manage, and mitigate risks. To meet the objective of this paper, a survey was designed and conducted in the Hong Kong construction industry in which over 140 respondents from different disciplines, with experience in BIM projects, have participated. Based on the analysis of the survey data, the most severe and frequently occurring BIM risks and their potential mitigation strategies were identified and discussed in this paper.

• Journal of The Geomorphological Association of Korea
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• v.26 no.2
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• pp.1-14
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• 2019

This study analyzed the relativity between block stream and talus distributions by employing a likelihood ratio approach. Possible distribution sites for each debris slope landform were extracted by applying a spatial integration model, in which we combined fuzzy set model, Bayesian predictive model, and logistic regression model. Moreover, to verify model performance, a success rate curve was prepared by cross-validation. The results showed that elevation, slope, curvature, topographic wetness index, geology, soil drainage, and soil depth were closely related to the debris slope landform sites. In addition, all spatial integration models displayed an accuracy of over 90%. The accuracy of the distribution potential area map of the block stream was highest in the logistic regression model (93.79%). Eventually, the accuracy of the distribution potential area map of the talus was also highest in the logistic regression model (97.02%). We expect that the present results will provide essential data and propose methodologies to improve the performance of efficient and systematic micro-landform studies. Moreover, our research will potentially help to enhance field research and topographic resource management.

• The Korean Journal of Food & Health Convergence
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• v.10 no.2
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• pp.13-17
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• 2024

Oxygen is necessary to sustain life, but reactive oxygen species (ROS) produced by oxygen metabolism can cause mutations and toxicity. ROS can damage cellular macromolecules, leading to oxidative stress, which can accelerate cell death and aging. ROS generated in food affect the taste, color, and aroma of food, and high levels of ROS in meat can cause spoilage. Superoxide dismutase (SOD) plays an important role in scavenging ROS in food and reducing their toxicity to organisms. SOD exerts its antioxidant effect by catalyzing the breakdown of O₂-• to H₂O₂. As a natural antioxidant, SOD has the ability to regenerate and maintain its activity over a long period of time without depletion, unlike chemical antioxidants that may have side effects or stability issues. This antioxidant effect of SOD has great potential in a variety of industries, and in the food industry it can be utilized to improve product quality and provide safe and healthy products to consumers. By disrupting the SOD2 and SOD3 genes in Candida albicans, we studied the effects of SOD2 and SOD3 genes on the antioxidant system, suggesting its potential as a natural antioxidant.

• Carbon letters
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• v.12 no.3
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• pp.121-130
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• 2011

Public concern has recently increased over the potential risk of toxic elements emitted from anthropogenic sources. Among these, mercury has drawn special attention owing to its increasing level of bioaccumulation in the environment and in the food chain, with potential risks for human health. This paper presents an overview of research related to mercury control technology and identifies areas requiring additional research and development. It critically reviews measured mercury emissions progress in the development of promising control technologies, including catalytic oxidation, sorbent injection, photochemistry oxidation, and air pollution control devices.

• Proceedings of the Korean Geotechical Society Conference
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• 1991.10a
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• pp.34-46
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• 1991

The slope stabi1ity analyses for Carsington dam were performed by using the computer program STABL and PC-SLOPE. The slip surface predicted by STABL can differ from the true slip surface. This is due to the characteristics of searching technique of the program STABL. Hence various possible potential slip surfaces must be examined using the program STABL. Various methods of analysis are employed in the program PC-SLOPE. A resonable factor of safety can be obtained by comparing the various values, and the potential slip surface can be predicted well relatively. The shear strength parameters of ctitical or residual state must be investigated as well as the peak strength for the case of the Carsington dam, where the deformation took place over long periods.