• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.251-253
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• 2000

본 연구는 대전 1,2 공단 지역을 대상으로 발암 금속 6종(As Be, Cd, Cr, Ni 및 Pb)을 포함한 15종의 독성 금속을 선정하여 유도결합 플라스마 분광법(ICP-MS)을 이용하여 3년간 분석하고 이 농도 자료에 근거하여 각 금속의 확률론적 농도를 평가하고자 한다. 대기중 부유분진은 대전시 대화동(대전 1,2 공단내 대화동 동사무소 건물 옥상)에 high-volume air sampler(Graseby Andersen : SAUB-10H Model, USA)를 약 0.85$\textrm{m}^3$/min으로 운전하여 시료당 공기량이 약 1,200 $\textrm{m}^3$가 유지되도록 포집하였다. (중략)

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.04a
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• pp.290-293
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• 2008

In this study, the Computational Fluid Dynamics (CFD) has been used to analyze the smoke movement and the carbon monoxide concentration distribution, both vertically and longitudinally, in a compartment, based on conservation laws. The Fire Dynamics Simulator (FDS) developed by National Institute of Standards and Technology (NIST) was used for numerical simulations using Reynolds averaged Navier-Stokes equations (RANS) model to solve for time-averaged properties. Results show, as a function of time, a detailed distribution of temperature and carbon monoxide concentration changing against the height above the floor and those changes alongside the distance away from the fire source. Fire-induced smoke and toxic gases like CO are more dangerous in a confined space. The result of study may contribute in designing the smoke evacuation system based on the precise tenable condition.

• Advances in Traditional Medicine
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• v.4 no.1
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• pp.49-52
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• 2004

The total alkaloid fraction of the methanolic extract of Solanum pseudocapsicum unripe fruits was tested for its in-vivo anticancer activity against Dalton's Lymphoma Ascites model in mice. The total alkaloid fraction at 5.0 and 10.0 mg/kg body weight showed significant increase in the mean survival time and the percentage increase in the life span of tumor bearing mice. The increase in the body weight was found to be less than that of the control. However, the treatment at 20 mg/ kg body weight was found to be toxic and showed a decrease in the mean survival time, and body weight when compared to control mice. The antitumor activity observed may be due to the cytotoxic activity of the total alkaloid fraction.

• Journal of Sensor Science and Technology
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• v.25 no.6
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• pp.394-398
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• 2016

In this paper, a fire detection system based on quantitative risk estimation is presented. Multiple sensors are used to build a comprehensive indicator that represents the risk of fire quantitatively. The proposed fire risk estimation method consists of two stages which determines the occurrence of fire and estimates the toxicity of the surveillance area. In the first stage, fire is reliably detected under diverse fire scenarios. The risk of fire is estimated in the second stage. Applying Purser's Fractional Effective Dose (FED) model which quantitates harmfulness of toxic gases, the risk of the surveillance area and evacuation time are calculated. A fire experiment conducted using four different types of combustion materials for the verification of the system resulted in a maximum error rate of 12.5%. By using FED calculation and risk estimation methods, the proposed system can detect various signs of fire faster than conventional systems.

• Proceedings of the Korea Information Processing Society Conference
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• 2019.10a
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• pp.795-797
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• 2019

In this paper, we propose a method to generate adversarial examples for toxicity detection neural networks. Our dataset is represented by a one-hot vector and we constrain that only one character is allowed to be modified. The location to be changed is founded by the maximum area of input gradient, which represents the most affecting character the model to make decisions. Despite the fact that we have strong constraint compared to the image-based adversarial attack, we have achieved about 49% successful rate.

• Advances in Energy Research
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• v.8 no.4
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• pp.233-241
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• 2022

Biodiesel is a non-polluting and non-toxic energy source that can replace conventional diesel. However, the higher production cost and raw material scarcity became challenges that obstruct the commercialization of biodiesel production. In the current investigation, fried cooking oil is used for biodiesel production in a hydrodynamic cavitation reactor, thus enhancing raw material availability and helping better waste oil disposal. However, due to the cavitation effect inside the reactor, the hydrodynamic cavitation reactor can give biodiesel yield above 98%. Thus, the use of orifice plates (having a different number of holes for cavitation) in the reactor shows more than 90% biodiesel yield within 10 mins of a time interval. The effects of rising temperature at different molar ratios are also investigated. The five-hole plate achieves the highest yield for a 4.5:1 molar ratio at 65℃. And the similar result is predicted by the response surface methodology model; however, the optimized yield is obtained at 60℃. The investigation will help understand the effect of hydrodynamic cavitation on biodiesel yield at different molar ratios and elevated temperatures.

• Hanyang Medical Reviews
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• v.34 no.3
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• pp.130-136
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• 2014

Animals find nutritious foods to survive, while avoiding aversive and toxic chemicals through the chemosensory faculties of olfaction and taste. The olfaction is comparatively well characterized, but the studies of taste are only recently developing since after 2000. Genetic, immunohistochemistry, and electrophysiological studies with knock-out transgenic mice opened up the taste field in mammals. Taste in insects has been only recently been studied after mammalian taste receptors were identified. Flies also discriminate the differences of sweet, salty and sour food, while being able to detect and reject potential foods contaminated with toxins or detrimental chemicals. These discriminatory abilities indicate that flies house basic taste receptors in their taste organs like humans. For the last decade, the sweet and bitter gustatory receptors in Drosophila have been characterized. In this review, we compare the taste anatomy between humans and insects. We also introduce five canonical taste sensations in Drosophila. In addition, we introduce new taste repertoires, that fruit flies can sense water and fatty acids as well as the carbonation buffer in beverage. These studies on simple model organisms will open up a new potential for scientists to further investigate these characteristics in vertebrates.

• Communications for Statistical Applications and Methods
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• v.30 no.5
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• pp.517-530
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• 2023

Recent studies revealed that fine dust in ambient air may cause various health problems such as respiratory diseases and cancer. To prevent the toxic effects of fine dust, it is important to predict the concentration of fine dust in advance and to identify factors that are closely related to fine dust. In this study, we developed a Bayesian network model for predicting PM10 concentration in Seoul, Korea, and visualized the relationship between important factors. The network was trained by using air quality and meteorological data collected in Seoul between 2018 and 2021. The study results showed that current PM10 concentration, season, carbon monoxide (CO) were the top 3 effective factors in 24 hours ahead prediction of PM10 concentration in Seoul, and that there were interactive effects.

• Safety and Health at Work
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• v.11 no.3
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• pp.322-334
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• 2020

Background: Spontaneous combustion of coal is one of the factors which causes direct or indirect gas and dust explosion, mine fire, the release of toxic gases, loss of reserve, and loss of miners' life. To avoid these incidents, the prediction of spontaneous combustion is essential. The safety of miner's in the mining field can be assured if the prediction of a coal fire is carried out at an early stage. Method: Adularya Underground Coal Mine which is fully mechanized with longwall mining method was selected as a case study area. The data collected for 2017, by sensors from ten gas monitoring stations were used for the simulation and prediction of a coal fire. In this study, the fuzzy logic model is used because of the uncertainties, nonlinearity, and imprecise variables in the data. For coal fire prediction, CO, O₂, N₂, and temperature were used as input variables whereas fire intensity was considered as the output variable.The simulation of the model is carried out using the Mamdani inference system and run by the Fuzzy Logic Toolbox in MATLAB. Results: The results showed that the fuzzy logic system is more reliable in predicting fire intensity with respect to uncertainties and nonlinearities of the data. It also indicates that the 1409 and 610/2B gas station points have a greater chance of causing spontaneous combustion and therefore require a precautional measure. Conclusion: The fuzzy logic model shows higher probability in predicting fire intensity with the simultaneous application of many variables compared with Graham's index.

• Molecules and Cells
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• v.25 no.4
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• pp.531-537
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• 2008

Abnormal activation of nuclear factor kappa B ($NF-{\kappa}B$) probably plays an important role in the pathogenesis of Duchenne's muscular dystrophy (DMD). In this report, we evaluated the efficacy of curcumin, a potent $NF-{\kappa}B$ inhibitor, in mdx mice, a mouse model of DMD. We found that it improved sarcolemmic integrity and enhanced muscle strength after intraperitoneal (i.p.) injection. Histological analysis revealed that the structural defects of myofibrils were reduced, and biochemical analysis showed that creatine kinase (CK) activity was decreased. We also found that levels of tumor necrosis factor alpha ($TNF-\alpha$), interleukin-1 beta ($IL-1\beta$) and inducible nitric oxide synthase (iNOS) in the mdx mice were decreased by curcumin administration. EMSA analysis showed that $NF-{\kappa}B$ activity was also inhibited. We thus conclude that curcumin is effective in the therapy of muscular dystrophy in mdx mice, and that the mechanism may involve inhibition of $NF-{\kappa}B$ activity. Since curcumin is a non-toxic compound derived from plants, we propose that it may be useful for DMD therapy.