• Asian Journal of Atmospheric Environment
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• v.11 no.1
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• pp.37-53
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• 2017

The effectiveness of four air fresher (AF) systems was evaluated with respect to their removal efficiencies against offensive odorants. For this purpose, malodorous species were generated by exposing freshly cooked foods emitting odorants with levels moderately above their respective threshold values in a confined room. The deodorization efficiency of the four AF systems was then tested for a period of 30 min by estimating the extent of reduction in odorant levels after the operation of each AF. The removal efficiency of the four AF units against each odorant was evaluated as follows: (1) between AF products from different manufacturers, (2) between odorants and ultrafine particulate matter ($PM_{2.5}$), and (3) between operation and natural degassing. The average sorptive removal of odorants was generally <80% and considered less effective or non-effective relative to $PM_{2.5}$. Further examination of odor reduction, if evaluated in terms of odor indices like odor intensity (OI) and odor activity value (OAV), recorded a mean of 33% and 87%, respectively. The overall results of this study confirmed that all tested AF units were not effective to resolve odor problems created under our testing conditions.

• Science of Emotion and Sensibility
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• v.8 no.2
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• pp.129-135
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• 2005

The purposes of this study were to investigate the subjective preference for odors, which has been an important factor for selecting fabric softner, and to identify the structure of sensibility of odors. Among six different odors, the subjects preferred freesia, blue bianca, violet, herb, green tea, and peach, in that order. Compared to male subjects, female subjects preferred freesia, herb, and blue bianca. The structure of odor sensibility to freesia showed 5 different factors and the odor sensibility to peach showed 6 different factors. Therefore, the structure of odor sensibility according to different odors was a bit different. Common factors of freesia odor and peach odor were aesthetics, character, excitement and intensity.

• Clean Technology
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• v.23 no.1
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• pp.34-41
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• 2017

The scrubber wastewater should be replaced frequently to maintain efficiency. Most chemical companies consign scrubber wastewater, because there are no wastewater treatment facilities. So scrubber wastewater is not frequently replaced because of high treatment cost. For this reason, the most scrubber exhaust gas exceeds the odor emission limit or has a phenomenon that the odor intensity of exhaust gas becomes higher. Therefore we have developed a scrubber wastewater cleaning system consisting of filtration and adsorption processes. The scrubber wastewater cleaning system was applied two chemical companies. We evaluated the water quality and odor reduction effect before and after system application. As a result, scrubber wastewater quality improved by 50% or more, odor reduction efficiency of scrubber exhaust gas improved by 20% or more. And the total operating costs of the scrubber could be reduced by 40% or more.

• Journal of Animal Science and Technology
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• v.48 no.3
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• pp.467-478
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• 2006

Maintenance of an optimal air quality in the enclosed pig building is potentially important in terms of pig performance and farmer health. The objective of this on-site experiment is to evaluate and compare efficiencies of currently utilized biological additives to reduce odor emissions from the enclosed pig building. As a result, generally all the additives except for salt water, artificial spice and essential oil were proved ineffective in reducing odor generation. The beneficial effects of salt water, artificial spice and essential oil on odor reduction were highlighted on ammonia, odor intensity and offensiveness, and sulfuric odorous compounds, respectively. To efficiently utilize odor masking agent such as the artificial spice, ventilation rate should keep slightly lower than the optimal level. Essential oil functioned well as not only masking agent but also antimicrobial agent for reducing odor. To precisely quantify odor concentration, it should be measured by not the odor sensor but the olfactometry technique.

• 한국가스학회:학술대회논문집
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• 1999.09a
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• pp.215-220
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• 1999

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.670-680
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• 2022

Owing to the lack of a cold-chain distribution system, most seafood is generally distributed under room temperature conditions. However the degradation of freshness during the distribution process can lead to disputes between sellers and consumers. The most widely used method for low-temperature distribution for seafood includes packaging it with styrofoam boxes and cold packs. In this study, vacuum-packed frozen fillets of four fish species of [white meat (Paralichthys olivaceus and Sebastes schlegelii) and red meat (Scomber japonicus and Scomberomorus niphonius)] were placed in styrofoam boxes with cold packs. Thereafter, changes in chemical (including pH, volatile basic nitrogen, and trimethylamine), physical (odor intensity, hardness, and chewiness), and microbial (viable cell count) characteristics of the fillets were measured during storage at 25℃. To identify the suitable method of determining freshness during the room-temperature distribution, several factors were considered, which included significant difference verification, correlation coefficients, and economic efficiency (experimental cost and time). Volatile basic nitrogen, pH, odor intensity, and viable cell count are the most rapid and accurate freshness indicators for determining freshness of frozen fish fillets during.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.4
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• pp.240-245
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• 2015

This study aimed to provide the basic data to establish measures for the management of the public toilets and reduction of the offensive odor through the air dilution olfactory method and instrumental analysis about offensive odor dilution rate of public toilets, focusing on the Dong-gu, Daejeon Metropolitan City, Korea. The offensive odor intensities ranged from 10 degree to 669 degrees in the urinal toilets and from 31 to 464 in closet bowl toilets. Meanwhile, toilets that had offensive odor of more than 2.5, of which a civil complaint can be filed, were researched 6 (33%). Offensive odor intensities were different according to the closet bowl toilets of the flush, fermented and conventional methods and the year of their installation, but not according to the area of the toilets. As a result of the instrumental analysis targeting 6 public toilets to identify the offensive odor substance, the maximal concentration of $NH_3$ was 2.04 ppm and the average concentration was 0.67 ppm, but $H_2S$, $CH_3SH$ and $(CH_3)_3N$ were not detected. In the fermented and conventional public toilets were not soaps, air fresheners and wastebaskets. Just 50% of the flush toilets had toilet tissue.

• Journal of Biosystems Engineering
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• v.30 no.2 s.109
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• pp.121-126
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• 2005

In this study, a commercial electronic nose system was used to detect contamination of Salmonella bacteria. Odors from growth media contaminated with Salmonella typhimurium, Salmonella enteritidis, or Escherichia coli were collected and analyzed to evaluate a possibility of rapid detection of pathogen. Odor chromatograph showed that S. typhimurium, S. enteritidis, and E. coli had 7,6, and 9 main peaks, respectively. Retention time and intensity of the peaks were distinct for different bacteria species. Principal component analysis (PCA) were also performed to clarify odor differences. Analysis results showed that the odors for uncontaminated growth medium were differently grouped from the odors of contaminated one. The odor from the bacteria growth identified with two principal components, PC 1 and PC2. In PCA figures, odor groups were moved from left to right of PC 1 with elapse of the bacteria growth time. The electronic nose system could detect odors of S. typhimurium, S. enteritidis, E. coli when their concentration were $1.85\times10^6\;cfu/g,\;2.25\times10^6\;cfu/g,\;and\;1.8\times10^5 cfu/g$, respectively.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.299-305
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• 1998

It was investigated to identify the volatile compounds of commercial vinegars by dynamic headspace sampling GLC-mass spectrometry, and additionally to evaluate the difference of sensory odor properties among vinegars such as brewed, cider, brown rice and persimmon vinegars. Thirty compounds were identified in four kinds of vinegar, which were composed of 9 carbonyl compounds, 12 esters, 6 alcohols and 3 acids. 3-Hydroxy-2-butanone could be merely detected in some of vinegar samples, and persimmon vinegar was characterized to include more various alcoholic compounds compared to the other kinds of vinegar. 3-Methyl-1-butanol was not detected from any samples of brewed vinegar, but from the most of cider, brown rice and persimmon vinegars. Persimmon vinegar has shown high strength of background odor intensity, and consequently was appeared to be inferior in background (p<0.05) and overall(p<0.01) odor preference scores to cider, brewed and brown rice vinegars.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.4
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• pp.415-422
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• 2008

The emission characteristics of odorous compounds discharged from the major environmental treatment facilities in Chungju were closely investigated by an ammonia passive sampler and by analyzing a questionnaire of the public complains. Amongst the four major emission sources, the manure treatment facility showed the highest concentration. The major components were sulfur compounds including H$_2$S, tri-methyl amine, and aldehydes. The foodwaste treatment processes releases sulfur compounds and aldehydes. Municipal waste water treatment facility emits a high concentration of acetaldehyde. It was found that the perceived odor level depends on the meteorological condition, and the odor intensity was higher at midnight than daytime.