• Journal of Sensor Science and Technology
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• v.28 no.1
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• pp.7-12
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• 2019

Significant progress has been made recently in detection of highly sensitive volatile organic compounds (VOCs) using chemical sensors. Combined with the progress in design of micro sensors array and electronic nose systems, these advances enable new applications for detection of extremely low concentrations of breath-related VOCs. State of the art detection technology in turn enables commercial sensor systems for health care applications, with high detection sensitivity and small size, weight and power consumption characteristics. We have been developing an intelligent electronic nose system for detection of VOCs for healthcare breath analysis applications. This paper reviews our contribution to monitoring of respiratory diseases and to diabetic monitoring using an intelligent electronic nose system for detection of low concentration VOCs using breath analysis techniques.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.4
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• pp.468-476
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• 2006

Hazardous air pollutants (HAPs) have high toxicity and bioaccurnulation potentials into human body even inbsmall amount (levels of ng/$m^3$). As the levels of HAPs might be controversial, it has been become essential to establish the analysis method for correct results. In this study, various analysis methods of VOCs and Aldehydes were compared in order to select the proper methods in our condition. Sampling and analysis method of VOCs were followed to EPA TO-14a and TO-17. VOCs were collected in absorption tube and separated by thermal desorption unit then analyzed by GC/MSD. Aldehydes were sampled in DNPH-cartridge and extracted into solution then analyzed by HPLC as the same condition of EPA TO-13a. This study also shows the results of QA/QC system of selected methods. Some experiments could be improving the data assurance blank test, calibration check, repetition precision check, the determination of detection limit and reproducibility of the retention time. Precisions of VOCs and aldehydes were ranged in 2$\sim$9% and 1$\sim$4% RSD, respectively. Recovery rate of VOCs showed variable ranges from 60 to 133.5%. MDL of VOCs and aldehydes were 0.044$\sim$0.284 ppb and 0.14$\sim$1.02 ng, respectively.

• Proceedings of KOSOMES biannual meeting
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• 2007.05a
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• pp.21-26
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• 2007

The Protocol adopted in Sep. 1997 included the new Annex VI of MARPOL 73/78, which entered into force on 19 May 2005. Revision for the accept MARPOL Annex VI with make public on 29 Dec. 2005 and enforce on 29 Jun. 2006. For all that not installation at oil terminal or if installed do not used. The purpose of this study is to research and evaluate the methods of sampling and analysis, and the pollution measure of existed VOCs during the bulk liquid cargo operation at vessels. As the sampling instrument of VOCs, Tedlar bag has the effect of decrease in concentration by the chemical reaction and absorption, and the method using the solvent extraction has error cause because of the extraction, the absorption tube has error by the breakthrough. But canister is the best sampling instrument because of having no sampling mistake. The study on VOCs emission is not sufficient for the research on the pollution cause and the analysis data on the HAP during the bulk liquid cargo operation at vessels. Hence, monitoring on the management hazardous VOCs need to be continued during the cargo operation at vessels and VOCs management field must be study for the make progress at a good pace for reason of crew's health.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.3
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• pp.129-137
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• 2018

VOCs have been used as the most definitive resource to reflect customer feedback when developing products and services. However, due to the development of the Internet and the emergence of SNS, VOC is no longer the only channel that represents customer opinions. There are also a number of studies showing that many customers express complaints through channels other than VOCs. In this paper, we analyze the difference between the official VOC data and the data collected through the external channel, and suggest ways to reflect the various opinions of customers. To do this, this study uses keyword analysis that can identify differences according to frequency through social network, modular analysis to distinguish topics according to centrality and similarity, and emotional analysis to confirm word polarity (positive and negative). The results of this study show that the opinions of the customers were different depending on channels such as VOCs and external channels. Therefore, the collected data through VOC as well as external channels should be used in order to reflect the opinions of customers. In particular, this paper confirms that the results of one channel may vary depending on the channel characteristics even for the same channel. This confirms that collecting voc only on certain channels may differ from what real customers require. Therefore, data collected through VOCs as well as external channels must be used to reflect various customer feedback.

• Analytical Science and Technology
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• v.27 no.6
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• pp.284-291
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• 2014

The handling process of car indoor air quality is composed of 2 steps of testing. First, assambly part is tested to find a source of car indoor VOCs. Second, cut sample of unit component is tested to find a source material of VOCs emission. If the source material of VOCs emission is found, it can reduce car and assembly part of VOCs by improving material. As cut sample testing has problem of emission from cut surface to find the source of VOCs, it needs to apply unit components testing method. The aim of study is to evaluate VOCs impact factor of unit components in assembly parts. ISO 12219-5 test method reflects not only material effect but also surface area effect by testing unit component without cutting. The unit components of doortrim and console, were tested by ISO12219-5. And it could figure what unit component is main source of VOCs in assembly. And quantity conversion Factor which gets by testing assembly and unit components can be used to make guideline of ISO 12219-5.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.2
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• pp.191-198
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• 2000

For a characterization of the pretreated waste automotive catalyst the following analysis techniques were applied : EA(Elemental Analysis) BET(Brunaure-Emmett-Teller) and ICP-AES(Inductively Coupled Plasma-Atomic Emission Spectrometry). The combustion activity of waste automotive catalyst was investigated for methanol acetaldehyde and toluene as model VOCs in a fixed bed reactor. carbon deposit amount was decreased with increasing catalyst showed a good catalytic activity for VOCs combustion at 40$0^{\circ}C$. Catalytic activity for methanol acetaldehyde and toluence combustion was very excellent and decreased with mileage. The catalytic activity of a waste automotive catalyst for methanol combustion increased after acid treatment. The acid effect of catalytic activity was summarized as follows: HNO3>HCI>H2SO4>CH3COOH. The waste automotive catalyst regenerated by the pretreatment method might have a excellent catalytic activity for VOCs combustion.

• Bulletin of the Korean Chemical Society
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• v.22 no.2
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• pp.171-178
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• 2001

A Purge and Trap Concentrator has been used to analyze various volatile organic compounds in water, operating several parameters affecting the extraction efficiencies of these compounds. The object of the present study was to observe the purge efficiencies of 40 volatile organic compounds (VOCs) in water, according to the change of parameters (purge time, dry purge time, sample temperature), and to determine the optimum condition of analysis of VOCs. The Purge and Trap Concentrator was interfaced with a narrow capillary connected to a gas chromatography mass spectrometer. At this condition, the detection limits of VOCs were in the range of 0.1-0.5 ㎍/L.

• Bulletin of the Korean Chemical Society
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• v.23 no.3
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• pp.488-496
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• 2002

SPME techniques have proven to be very useful tools in the analysis of wide VOCs in the air. In this study, we estimated VOCs in ambient and workplace air using a Tedlar ba /SPME/GC/MS system. The calibration curve was set to be linear over the range of 1-30 ppbv. The detection limits ranged from 10 pptv to 0.93 ppbv for all VOCs. Reproducibility of TO-14 target gas mixtures by SPME/GC/MS averaged at 8.8 R.S.D (%). Air toxic VOCs (hazardous air pollutants, HAPs) containing a total of forty halohydrocarbons, aromatics, and haloaro-matic carbons could be analyzed with significant accuracy, detection limit and linearity at low ppbv level. Only reactive VOCs with low molecular weight, such as chloromethane, vinylchloride, ethylchloride and 1,2-dichloro-ethane, yielded relatively poor results using this technique. In ambient air samples, ten VOCs were identified and quantified after external calibration. VOC concentration in ambient and workplace air ranged from 0.04 to 1.85 ppbv. The overall process was successfully applied to identify and quantify VOCs in ambient/workplace air.

• Analytical Science and Technology
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• v.18 no.2
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• pp.130-138
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• 2005

Volatile organic compounds (VOCs) have been recognized as major contributor to air pollution. Catalytic oxidation in VOCs can give high efficiency at low temperature. In this study, monometallic Pt, Ir and bimetallic Pt-Ir were supported to $TiO_2$. Xylene, toluene and methyl ethyl ketone (MEK) were used as reactants. The monometallic or bimetallic catalysts were prepared by the excess wetness impregnation method and characterized by XRD, XPS and TEM analysis. Result reveal that Pt catalyst has higher conversion than Ir catalyst and Pt-Ir bimetallic catalysts. The existence of multipoint actives in, Pt-Ir bimetallic catalysts gives improved performance for the Pt metalstate. Bimetallic catalysts have higher conversion for VOCs than monometallic ones. The addition, VOCs oxidation follows first order kinetics. The addition of small amount of Ir to Pt promotes oxidation conversion of VOCs.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.12
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• pp.906-917
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• 2013

The purpose of this study is to quantify volatile organic compounds (VOCs) in gas sample using headspace solid-phase microextraction (HS-SPME) coupled to GC analysis. The optimal HS-SPME conditions was CAR/PDMS fiber and 30 min absorprion time for the analysis of various VOCs. In optimal conditions, 80 VOCs could be detected within 1 ppbv and even less than 0.0005 ppbv especially in the case of BTEX. However, fiber reproducibility on adsorption efficiency was 1~9.2% (between the same fiber) and 5.9~13.5% (between the other fiber). We successfully determined 35 VOCs in landfill gas with this method and found that VOCs of high concentration are emitting from vent pipe of closed/open landfill site under the HS-SPME conditions. This method may apply to VOCs/odor determination from various atmospheric environmental samples as well as landfills.