• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.419-425
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• 2011

Changes in the flavor of muskmelons stored at different temperatures were examined to judge aroma patterns during storage. A mass-spectrometry based electric nose was used to distinguish the subtle differences in the muskmelon's volatile compounds. The data were used for a discriminant function analysis (DFA), and then the partial least square algorithm was used for a quantitative analysis. Volatile components in the muskmelons increased with storage, and the first discriminant function score (DF1: $r^2$=99.88%, F=3072.5) moved from a positive position to a negative position as the storage period increased. The proper point of maturity was anticipated as the $28^{th}$ day at 0$^{\circ}C$, $21^{st}C$ day at 4 and 7$^{\circ}C$, and $14^{th}$ day at 10$^{\circ}C$. Also, using the DF1 score we could predict the general tendency (vitamin C, stem moisture, acidity) of the muskmelons. The electronic nose revealed that the major volatile compounds that changed during storage of the melons were ethyl ethyl acetate, butyl acetate, nonanol, dodecanoic acid, hexadecanoic acid and tricosane. The amount of volatile compounds detected increased during storage.

• Journal of Platform Technology
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• v.11 no.2
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• pp.54-65
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• 2023

Due to the nature of electric vehicles, the batteries used for electric vehicles have a very large rated capacity. If an electric vehicle runs for a long time or an electric vehicle is abandoned due to a traffic accident, the electric vehicle battery becomes a waste battery. Even in vehicles that are being abandoned, the remaining capacity of waste batteries for electric vehicles is sufficient for other purposes. Waste batteries for automobiles are very expensive, so they need to be recycled and reused, but there was a problem that the standards for measuring the performance grade of waste batteries for recycling and reuse were insufficient. As a method for measuring the remaining capacity of waste battery, the most stable and reliable method is to measure the remaining capacity of battery using full charge and discharge. However, the inspection method by the full charging and discharging method varies depending on the capacity of the battery, but it takes more than a day to inspect, and many people are making great efforts to solve this problem. In this paper, an electric vehicle battery residual capacity analysis technique using voltage deviation between cells was studied and analyzed as a method to reduce inspection time for electric vehicle batteries. To this end, a full charging and discharging-based capacity measurement system was constructed, experimental data were collected using a nose or waste battery, and the correlation between the voltage deviation and the remaining capacity of the battery pack was analyzed to verify whether it can be used for battery inspection.

• Journal of Sensor Science and Technology
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• v.31 no.6
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• pp.389-396
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• 2022

Quartz crystal microbalance (QCM) based sensors are used for various applications owing to advantages such as excellent accuracy and precision, rapid response, and tiny footprint. Traditional applications of QCM-based sensors include biological sensing and thin-film thickness monitoring. Recently, QCMs have been used as functional material for novel physical and chemical detections, and with improved device design. QCM-based sensors are garnering considerable attention in particulate matter sensing and electric nose application. This review covers the challenges and solutions in physical, chemical, and biological sensing applications. First, various physical sensing applications are introduced. Secondly, the toxic gas and chemical detection studies are outlined, focusing on introducing a coating method for uniform sensing film and sensing materials for a minimal damping effect. Lastly, the biological and medical sensing applications, which use the monomolecularly decorating method for biomolecule recognition and a brief description of the overall measuring system, are also discussed.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.53
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• pp.69-78
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• 1999

We developed an apparatus for odorous stimuli control to record olfactory evoked potentials from human scalp. The characteristics of the apparatus were as follows. 1. Translating the subjects respiration into electric signals with a sensor attached to the nose. The period and timing of odorous stimuli could be adjusted, so that stimuli could be synchronous with respiration. 2. The respirations translated into electric signals were made constant in amplitude by using an auto gain control circuit. 3. The interstimulus interval of odorous could be arbitrarily selected once every 1 to 9 respirations so that adaptation could be prevented. We obtained olfactory - evoked potentials (OEPs) to odorous stimuli using this apparatus from the site of Cz, whose positive peak latencies were approximately $180{\pm}23ms$. Such response were not recorded if oxygen stimuli were used instead of odorous or with click sounds produced by the switching electromagnetic valve.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.1009-1013
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• 2011

Seoul Metro Line 1 to 4 guests per day to 4.5 million people have been using the subway. This is close to the city population, 57 percent of people use the subway and found that 57 percent of people use the subway and found that this is close to the city population. Motor vehicle indoor air quality, especially of the major factors affecting is passenger's clothing, cosmetics, adhesives and formaldehyde by the action and so are able to keep. Enclosure 30ppm formaldehyde during prolonged exposure at concentrations above the nose, bronchial cough and a burning can cause symptoms. It is necessary to introduce an appropriate ventilation system. 1-4 Line Press in 2008, leaving the subway, and normally the train measured in room air quality. Measurements in 2005, $19.3{\sim}83{\mu}g/m^3$, 2008 Year ND ~ $61.7{\mu}g/m^3$ is. When congestion(rush hour) to temporarily increase the formaldehyde can result in a higher number. Automatic detection of formaldehyde and improve ventilation to a practical system, and it is necessary to chatneun. In research since 2006, Removal of formaldehyde were analyzed for the study. the passengers on the effects of formaldehyde in rush hour, the plan for increasing the ventilation through the analysis of various factors, such as electric vehicle practical ways to improve air quality have been studied.

• Journal of Oriental Neuropsychiatry
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• v.4 no.1
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• pp.77-97
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• 1993

Human and animals are living by acclimation to environmental changes like high and cold temperature, nose, confinement, etc. If the above changes reach a defined levels, some physiological abnormal state could appear, which we call them as stress state. Catecholamines are excreted by the sympathetic-adrenomedullary system in free from in urine. Catecholamines are derived from the adrenal medulla and urinary epinephrine can be taken as a rough estemation of the activity of this gland. Many scientist reported the endocrinological change, excretion of catecholamine and its metabolites, stomach ulcer formation, etc. under the condition of the confinement and high temperature. In this study author gave restraint, electric shock and immersion stress to rats by administrating by HPLC and got the following results. 1. In the restriant experiment, epinephrine contents in control rat was 194.7 ng, but in Bohyulanshintang administered rat urine 198.9 ng of epinephrine was found. 2. In the electrical shock experiment, 199.5 ng of epinephrine was found in the control rat urine, but in Bohyulanshintang administered rat urine epinephrine content was 142.4 ng. 3. Dopamine contents in control rat urine the immersion environment was 118.9 ng, but in Bohyulanshintang administered rat urine only 55.2 ng of dopamine was found. 4. Incontrol rat stomach there appeared focal erosion and inflamatory exudate, but in experimental group these symptom were turned to mild condition.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.118-122
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• 2000

Recently, High accuracy and precision are required in various industrial field especially, semiconductor manufacturing apparatus, Ultra precision positioning apparatus, Information field and so on. Positioning technology is a very important one among them. For composition of this technology, the development of system with high speed and high resolution is needed. At start point and end position vibration must be repressed on this system for composition of position control. This vibration is arisen nose, is increased setting time, is reduced accuracy. Especially, repressed for the lead with high speed. The small actuator with high speed and high resolution is need to repression against this residual vibration. This actuator is, for example, piezo actuator, piezoelectric material that converting from electronic signal to mechanical force is adequate material, beacause of control of control to position and force. In this study, piezo electric material is used to actuator, ultra precision positioning apparatus with stage of hinge structure is designed, simulation is performed, control performance is tested by producing apparatus. For easy usage and stability in industrial field, we perform to simulation and to position control test by digital PID controller.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.651-653
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• 2000

In this study, a distance-measurement system was proposed by using principle of the Michelson Interferometer and a fundamental research was carried out. In case of the rnichelson interferometer, relativity distance was measured by relativity-difference of two course of light. But wavelength of light source were changed in this system in order to use interference phenomenon of michelson interferometer in measuring absolutely distance. Wavelength of input signal were changed periodically and were interfered electrically. So absolute distance can be calculated by using $\Delta\lambda$ and measuring $\eta\Delta$ in electric interference. Nose by a external factor was small in this system because a absolutely distance was measured by phase difference. And a dispersion of noise was small in pulse-echo response because a error was occurred in range of phase difference of signal. Also very wide range can be measured by only single system because informations of distance were acquisited in wavelength level.

• Journal of the Korean Society of Tobacco Science
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• v.27 no.1 s.53
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• pp.83-93
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• 2005

This study was conducted to evaluate the effect of additives in low sidestream cigarette papers, such as Mg$(OH)__2,\;TiO_2\;and\;KH_{2}PO_4$ on the delivery of mainstream and sidestream smoke. From the analysis of tar and nicotine in sidestream and mainstream smoke, the delivered ratios of tar and nicotine by sidestream to mainstream smoke in common cigarette paper were 5.32 and 8.60, respectively. However, the delivered ratios of those of the paper containing $Mg(OH)_2\;were\;2.25\~3.23,\;4.86\~7.14,\;Mg(OH)_2\;and\;KH_{2}PO_4\;were\;2.12\~2.92,\;4.67\~6.89,\;TiO_2\;was\;3.21,\;7.51 $ respectively. The deliver patterns of semi-volatile components in the cigarettes were similar each there, but a slight different pattern in the amount was observed depending on the kinds of compounds added in cigarette papers. In the cigarettes made of $Mg(OH)_2$ added paper, the aromatic components such as benzene, toluene and phenol were generated more while the aliphatic components like neophytadiene, ethyl decanoate were delivered less than the cigarettes made of common cigarette papers. However, the cigarettes manufactured with $Mg(OH)_2\;and\;KH_2PO_4$ added paper showed an opposite trend. The cigarettes made of $TiO_2$ added paper showed relatively low delivery in the most compounds measured. In sensory evaluation, cigarette papers tested were noticed a distinguishable sensory character between the low sidestream smokes with additive cigarette papers except $TiO_2$ added one. Moreover, aroma patterns detected by a electronic nose system in TPM were a similar tendency.

• Food Science of Animal Resources
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• v.32 no.4
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• pp.467-475
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• 2012

This study was carried out to investigate the effect of the addition level (0 ppm, 400 ppm, 800 ppm, and 1,200 ppm) of green tea extract on the lactic acid bacteria, oxidative stability, and aroma in kimchi-fermented sausage. The sample sausages were fermented at $24^{\circ}C/RH$ 89% until attained to a pH value of 4.9 (for 17 h), and then dried at $10^{\circ}C/RH$ 75-80% for 6 d. The lactic acid bacteria count and pH value were 7.5-7.7 Log CFU/g sausage and 4.30-4.33, respectively, at 6 d of ripening. The results of those did not show significant differences among all treatments. The formation of TBARS (2-thiobarbituric acid reactive substances) was significantly lowered by increasing the addition level of green tea extract. During ripening periods, the CIE $L^*$ and $a^*$ values decreased; however, the $b^*$ value increased due to the addition of green tea extract. Utilizing an electric nose, the aroma pattern was clearly discriminated between green tea extract treatments and the control. Therefore, in kimchi-fermented sausages, the high addition level of green tea extract improved the lipid oxidation stability. In addition, regardless of the addition level, green tea extract changed the aroma while reducing the color stability. Moreover, it did not have any effect on the growth of lactic acid bacteria.