• Journal of the Korea Safety Management & Science
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• v.1 no.1
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• pp.183-195
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• 1999

Most of chemical plant are using toxic and dangerous materials, inflammable and poisonous. There are many accidental dangers by escaping of fire, explosive and poisonous materials in case of high temperature and pressure. The accidents lead to taking employer's and local people's life and environmental contamination. Therefore, 27 small-medium chemical plant, which size is 30 ∼ 200 employees out of safety management agent ill the area of A was selected in this study. The problems of safety management and several countermeasures at the chemical plants was indicated through the analyzed data. Prior to this analysis, top managers' concerns, equipment maintenance for the safety management are needed. For the future, calamity prevention countermeasures by industrial disaster analysis are needed and active safety management programs are investigated for the industrial disaster prevention and productivity enhancement at the chemical plant.

• Journal of the Korean Chemical Society
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• v.31 no.1
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• pp.64-70
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• 1987

Rare earth elements including Y and Th in the monazite were separated and determined by X-ray fluorescence spectrometry. The matrix effects among the rare earth elements were simultaneously corrected by means of empirical coefficient method. The values of the coefficients were quite dependent on the number of the standards. However, the different set of coefficients led to the same results. The analytical results corrected by the present method agreed with those by the inductively coupled plasma spectrometry.

• Proceedings of the Safety Management and Science Conference
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• 1999.11a
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• pp.97-108
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• 1999

Most of chemical plant are using toxic and dangerous materials, inflammable and poisonous. There are many accidental dangers by escaping of fire, explosive and poisonous materials in case of high temperature and pressure. The accidents lead to taking employer's and local people's life and environmental contamination. Therefore, 27 small-medium chemical plant, which size is 30∼200 employees out of safety management agent in the area of A was selected in this study. The problems of safety management and several countermeasures at the chemical plants was indicated through the analyzed data. Prior to this analysis, top managers' concerns, equipment maintenance for the safety management are needed. For the future, calamity prevention countermeasures by industrial disaster analysis are needed and active safety management programs are investigated for the industrial disaster prevention and productivity enhancement at the chemical plant.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.231-236
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• 2013

Some cytotoxicity studies for the interpretation of the interaction between nanoparticles and cells are non-mechanistic and time-consuming. Therefore, non-biological screening methods, which are faster and simpler than in-vivo and in-vitro methods, are required as alternatives to current cytotoxicity tests. Here, we proposed a simple screening method for the analysis of the interaction between several AgNPs (bare-, citrate-, and polyvinylpyrrolidone-coating) and dye-containing vesicles acting as a biomimetic cell-membrane. The interaction between AgNPs and vesicles could be evaluated readily by UV-vis spectra. Absorbance deviation in UV-vis spectra revealed a large attraction between neighboring particles and vesicles. This was confirmed by (Derjagin, Landau, Verwey, and Overbeek) theory and DMF (dark-field microscopy) analysis. This proposed method might be useful for analyzing the cytotoxicity of nanoparticles with cell-membranes instead of in vitro or in vivo cytotoxicity tests.

• Journal of Soil and Groundwater Environment
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• v.20 no.3
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• pp.7-14
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• 2015

In this study, land farming and chemical oxidation of a diesel-contaminated site is compared to evaluate the environmental impact during soil remediation using the Spreadsheet for Environmental Footprint Analysis by U.S. EPA. Each remediation process is divided into four phases, consisting of soil excavation, backfill and transportation (Phase 0), construction of remediation facility (Phase 1), remediation operation (Phase 2), and restoration of site and waste disposal (Phase 3). Environmental footprints, such as material use, energy consumption, air emission, water use and waste generation, are analyzed to find the way to minimize the environmental impact. In material use and waste generation, land farming has more environmental effect than chemical oxidation due to the concrete and backfill material used to construct land farming facility in Phase 1. Also, in energy use, land farming use about six times more energy than chemical oxidation because of cement production and fuel use of heavy machinery, such as backhoe and truck. However, carbon dioxide, commonly considered as important factor of environmental impact due to global warming effect, is emitted more in chemical oxidation because of hydrogen peroxide production. Water use of chemical oxidation is also 2.1 times higher than land farming.

• Applied Microscopy
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• v.46 no.2
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• pp.76-82
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• 2016

Aloe vera has been used in the pharmaceutical, food and cosmetic industry for its therapeutic properties. However, there are not many current studies on the microstructure of A. vera compared to studies on the chemical constituents and health efficacy of A. vera. Therefore, we compared the morphology of an A. vera leaf using an optical microscope, a conventional scanning electron microscope (SEM) and a cryo-SEM. Especially, this study focused on observing the gel in the inner leaf of A. vera, which is challenging using standard imaging techniques. We found that cryo-SEM is most suitable method for the observation of highly hydrated biomaterials such as A. vera without removing moisture in samples. In addition, we found the optimal analytical conditions of cryo-SEM. The sublimation conditions of $-100^{\circ}C$ and 10 minutes possibly enable the surface of the inner leaf of A. vera to be observed in their "near life-like" state with retaining moisture. The experiment was repeated with A. arborescens and A. saponaria to confirm the feasibility of the conditions. The results of this study can be applied towards the basic research of aloe and further extend previous knowledge about the surface structures of the various succulent plants.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.11a
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• pp.267-267
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• 2019

The purpose of this study is to understand the risk of chemical product, Styrene Monomer(SM), shipped in a vessel. SM is harmful chemical product which can make injury, explosion and/or fire in a vessel. The understand of SM risk is very important to protect seafarer's body and vessel safety. This research can be expected that the understanding of SM risk by a seafarer's to prevent accidents by SM explosion/fire. In this study we used event tree analysis method using chemical reaction cased by explosion. As a result, we founded various chemical reaction and visualization for explosion path.

• Applied Science and Convergence Technology
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• v.23 no.6
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• pp.328-339
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• 2014

In this article, plasma monitoring tools and mulivariate analysis techniques were reviewed. Optical emission spectroscopy was reviewed for a chemical composition analysis tool and RF V-I probe for a physical analysis tool for plasma monitoring. Multivariate analysis techniques are discussed to the sensitivity improvement. Principal component analysis (PCA) is one of the widely adopted multivariate analysis techniques and its application to end-point detection of plasma etching process is discussed.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.542-549
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• 2023

Since the growing interest in surrogate modeling, there has been continuous research aimed at simulating nonlinear chemical processes using data-driven machine learning. However, the opaque nature of machine learning models, which limits their interpretability, poses a challenge for their practical application in industry. Therefore, this study aims to analyze chemical processes using Explainable Artificial Intelligence (XAI), a concept that improves interpretability while ensuring model accuracy. While conventional sensitivity analysis of chemical processes has been limited to calculating and ranking the sensitivity indices of variables, we propose a methodology that utilizes XAI to not only perform global and local sensitivity analysis, but also examine the interactions among variables to gain physical insights from the data. For the ammonia synthesis process, which is the target process of the case study, we set the temperature of the preheater leading to the first reactor and the split ratio of the cold shot to the three reactors as process variables. By integrating Matlab and Aspen Plus, we obtained data on ammonia production and the maximum temperatures of the three reactors while systematically varying the process variables. We then trained tree-based models and performed sensitivity analysis using the SHAP technique, one of the XAI methods, on the most accurate model. The global sensitivity analysis showed that the preheater temperature had the greatest effect, and the local sensitivity analysis provided insights for defining the ranges of process variables to improve productivity and prevent overheating. By constructing alternative models for chemical processes and using XAI for sensitivity analysis, this work contributes to providing both quantitative and qualitative feedback for process optimization.

• Journal of the Korean Institute of Gas
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• v.7 no.4 s.21
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• pp.61-66
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• 2003

The objective of this study is to develop a Cost-Benefit analysis system which would help us to make optimal decision among safety investment alternatives, calculating and comparing costs and benefits for facilities in chemical plants. So, the accident frequency analysis module and the accident damage prediction module were developed for estimating quantitative risks in chemical facilities, and domestic societal risk criterion was presented after the comparative analysis of major industrial cases and societal risk criteria of advanced countries like the Netherlands, Australia, U.S.A., U.K., and Germany. Also, the Cost-Benefit Analysis System which compares the safety investment alternatives based on their deduced net present values was developed through the selection of proper cost and benefit items by field studies