• Journal of Korean Society for Atmospheric Environment
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• v.34 no.2
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• pp.233-243
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• 2018

This study was carried out to characterize the ambient levels of PAH concentrations in Pohang city, where steel industry has been intensively developed. A large amount of PAH emissions from steel production and related industries in Pohang are concerned about the environmental health hazards of nearby residents. TSP samples were seasonally collected during 10 days at four sites in Pohang from April to December 2010. Each sample was collected for 24 hours using high-volume air sampler. All samples were extracted by $soxtec^{TM}$ before concentration of 1.0 mL. The concentrates were analyzed by GC/MS. The prevailing wind direction was southwest and west-southwest in Pohang during the measurement period. Variations of TSP concentrations appeared to be similar between four sites. The highest TSP concentration was found in fall, while the lowest in summer. The highest PAH concentration was found at an industrial site, while the lowest at a residential/commercial site. In the case of BaP, the average concentration at the industrial site was $0.63{\pm}0.66ng/m^3$, which was approximately 2 times of the residential/commercial site. The paired t-test (p<0.05) showed significant differences between industrial and residential area. Particulate PAH concentrations were higher in the winter and lower in the summer. The concentrations of BaP in winter were 2~10 times higher than those in the other three seasons. This study clearly demonstrated the impact of steel industry on the elevated levels of PAH in Pohang city.

• Journal of Fisheries and Marine Sciences Education
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• v.23 no.2
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• pp.153-161
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• 2011

Creating standards on thermal environment has been organized traditionally based on the youth and the manhood who are in mainly active layer of a society. However, traditional creating standards have differences from the physiology of the aged who have weak physical ability than younger person. As a result, it causes a health problem of the aged. Therefore, In this study, we had a basic study to create a comfortable thermal environment which had considered to a physical ability and a physiology of the aged, and build a ecological residence space to maintain health. We had several experiments with the aged; Experiment, Comfort Sensation Vote, Mean Skin Temperature and Analyzing HRV. The result have following by: 1)For the aged, the summer recommend temperature, $26^{\circ}C$, is appropriate within first 30 ~ 40 minutes, but it should be increasing the temperature after that time. 2) By considering PMV status and thermal feeling of the aged, they are prefer to higher temperature than normal setting of air-condition system. 3) In the condition of the summer recommend temperature, $26^{\circ}C$, they had answered in neutral or comfort with the comfort sensation vote. However, we had figure out that they had stress in a lower temperature by analyzing the result of HRV.

• Journal of Bio-Environment Control
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• v.11 no.2
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• pp.61-66
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• 2002

Double cropping system in a year in Kyoho grapes (Vitis labruscana L.) has currently been attempted in the plastic greenhouse. One of the problems in double cropping system is the promotion of bud break in summer season and shoot fertility. Effects of the control of soil moisture tension near the root zone and treatments of bud dormancy breaking agents on bud breaking in summer were examined to promote the bud break for the second fruiting. The lignification of shoots was induced in July or August by the control of soil moisture tension in root zone environment. The first shoot growth was almost the same as that in common plastic greenhouses. The highest bud break value appeared in the plot of cyanamide chemicals mixed with merit blue as over 75% bud break rate. The bud break rate in the discontinuing plot in irrigation showed significantly higher in bud break than that in the continuing plot in irrigation. Despite of the final high bud break rate, the time of bud break was irregular.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.5
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• pp.681-685
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• 2000

A computer software was developed in our laboratory to automatically control the pigs environment by the image analysis system (IAS), which monitors and analyzes the pig's behavior and feeds the results back to the computer hardware. Three feeding trials were conducted with growing pigs ($L{\times}Y$) to test the effectiveness of the IAS under various seasons. In all three trials, the open-sided conventional pens with half-slatted floor were used as controls; for the IAS treatment, fully-slatted floors were used in the windowless pens. Experiment 1 was conducted in the winter for 30 d with 24 growing pigs. There were two treatments (Conventional vs. IAS), and three pens (replicates) per treatment. During the growing period, the feed efficiency was significantly (p<0.05) improved by the IAS. In addition, the pigs reared under the IAS during the growing period displayed better growth rate during the finishing period than did the pigs reared under the conventional conditions. Experiment 2 was conducted in the summer for 30 d with 24 growing pigs. The experimental design was the same as Experiment 1. During the finishing period, all the pigs were kept in conventional open-sided pens until their market weights to evaluate their carcass characteristics. During the growing period, the growth rate and feed efficiency of the pigs in the IAS was better than those of the control pigs. In addition, various carcass characteristics were significantly improved by the IAS rearing during the growing period. Experiment 3 was conducted with 30 growing pigs for 30 d in the spring. The experimental design was the same as Experiment 1. No difference was found in growing performance between the control and IAS pigs. It could be concluded that the IAS is effective in providing optimum conditions for the growing pigs in summer and winter seasons. In addition, providing an optimum environment during the growing period results in improved growth rate, feed efficiency, and carcass qualities for the finishing pigs.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.5
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• pp.477-491
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• 2014

This study was carried out to evaluate the concentration variations of volatile organic compounds (VOCs) in the office environments located in a large urban area with respect to seasonality, smoking status, types of ventilation and heating. Indoor air sampling was undertaken in 37 and 30 offices in Daegu city during summer and winter, respectively. The VOC samples were collected using adsorbent tubes, and were determined by thermal desorption coupled with GC/MS analysis. The analytical method was validated for repeatability, method detection limits (MDL), and duplication precision. A total of 34 VOCs of environmental concern were determined, including 15 aromatics and 19 halogenated hydrocarbons. Average concentrations of BTEX appeared to 1.91 ppb, 22.98 ppb, 3.44 ppb, and 3.70 ppb, respectively. These values were relatively higher levels than those measured at homes and outdoor roadsides reported by other researches. In general, the concentrations of VOCs were higher in winter than summer, in smoking offices than non-smoking offices, in forced ventilation type than natural ventilation type, and in combustion heating than non-combustion heating offices. However, such differences were not always significant at a level of 0.05 by statistical tests (t-test and/or Mann-Whitney test) with some exceptions for BTEX and styrene. This study demonstrated that smoking status, ventilation type and presence of combustion sources indoors could be important factors on the elevated concentrations of some VOCs in the office environment.

• Journal of Korean Society on Water Environment
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• v.31 no.6
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• pp.637-643
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• 2015

This study has been carried out to provide the basic data obtained from the evaluation of the variation of water quality around the Chudong intake tower in Daechung resevoir, which may be able to help the establishment of a pure water supply policy. Five sites around the Chudong intake tower were selected, and the average data for recent ten years(from year 2004 to year 2013) were analysed. The average water quality around Chudong intake tower are as followed; pH 7.5, DO 8.7 mg/L, BOD 1.0 mg/L, COD 3.0 mg/L, SS 3.0 mg/L, TN 1.495 mg/L, TP 0.017 mg/L, and Chlorophyll-a 6.5 mg/m³ were matched the good class by comparing with the living environment standard of reservoir. COD values of higher than 3.0 mg/L after July were likely due to non-point pollutants and algae outbreak during rainy summer season. Total phosphorus rose sharply in the summer season, and then algae watch was issued consistently for average 40 days. Total nitrogen to total phosphorus ratio was average 90, and it is important to control the inflow phosphrous from small stream for proper management to block an algae growth according to eutrophication. It was recommended to operate the algae removing boats around intake tower from July to October, and was required advanced water treatment processes to remove NBD COD and bad odor and taste due to algae growth.

• Journal of Korean Society on Water Environment
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• v.30 no.4
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• pp.377-385
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• 2014

To study the fluctuations and relationship in climate change, environmental factors and cyanobacteria communities, we investigated Chudong station of the Daechung reservoir. The average annual temperature showed the maximum value ($13.9^{\circ}C$) from 1994, showed a gradually increasing pattern from 1969 to 2010 in the Daechung reservoir. The number of days with temperatures over $20^{\circ}C$, minimum temperature of the year and average temperature of the winter season patterns also showed a significant increase. The long-time changed in the annual precipitation were not showed a significant variation. The water temperature record comparatively high value in summer, declined in winter. At all period, the phytoplankton were highest biomass in July 2000, and then, showed comparative higher biomass in the summer months. Cyanobacteria taxa were also showed more than 50%. Emergence of cyanobacteria also appeared in November 2007, were prolonged emergence. The dominant genera of taxa were the dominant sphere (Microcystis spp.) until early 2000. After that, the dominant species were the dominant linear (Aphanizomenon spp., Anabaena spp.). Cyanobacteria were the most correlated with water temperature (r = 0.341, p<0.01) and phosphate concentration (r = 0.355, p<0.01).

• Asian Journal of Atmospheric Environment
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• v.2 no.1
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• pp.54-59
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• 2008

The most pivotal approach to improve subway indoor air quality (IAQ) is to examine the emission sources and particulate behavior. Therefore, the main objective of this study is to investigate the particulate behavior in the subway. In order to examine IAQ in the subway, a sampling and measurement campaign was carried out for 35 sites during the summer and winter seasons from May, 2005 to February, 2006. In case of 24 hour measurement, the mean concentrations ($PM_{10}$-24 hr) of platform and waiting room were $156.18{\pm}53.79{\mu}g/m^3$ and $111.00{\pm}53.31{\mu}g/ m^3$. Besides, as a result of 20 hour measurement, the mean concentrations ($PM_{10}$-20 hr) of platform and waiting room were $146.09{\pm}53.71{\mu}g/m^3$ and $99.08{\pm}42.77{\mu}g/m^3$, respectively. In general, $PM_{10}$-24 hr was higher than $PM_{10}$-20 hr, and both PM concentrations showed a high correlation coefficient (r=0.803). It was found that the $PM_{2.5}$ concentration ($l09.56{\pm}28.24{\mu}g/m^3$) in winter was higher than that ($83.66{\pm}57.82{\mu}g/m^3$) in summer.

• Korean Journal of Veterinary Service
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• v.34 no.4
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• pp.389-395
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• 2011

The aims of this study were to assess the lung lesions and to compare gross observations with histopathological findings in the lungs of slaughter pigs. During August of 2010 through July of 2011, the 1,200 lung samples were randomly collected from slaughtered pigs in Korea. We examined prevalence of lung lesions and classified the lung lesion according to the severity of lung lesions. For the comparison of gross lesions with histopathological findings, BALT hyperplasia was also examined. Among the tested samples, 1,100 (91.7%) had pneumonic lung lesions. In the seasonal prevalence of pneumonic lung lesions, spring was the highest followed by winter, summer and autumn, respectively. The mean pneumonic score ($mean{\pm}SD$) was $21.37{\pm}17.87$ and the highest gross lesion according to stages was 11~20% (27.2%, 326/1,200). The prevalence of pleuritis was 7.0% and the highest prevalence was determined in summer. In severity, the lungs collected in this study were frequently in chronic stage (36.4%, 437/1,200), and it was shown that BALT hyperplasia was more extensive in chronic lesion. In this study, the prevalence of pneumonic lung lesions showed a high side and appeared particularly high in the spring. Severity of lung lesion was the most prevalent chronic lesions which were consistent with histopathologic findings.

• Korean Journal of Heritage: History & Science
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• v.42 no.1
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• pp.158-186
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• 2009

The Gossi Cave, Natural Monument 219, extends horizontally for 3,388m with 215m elevation. 620m of the horizontal cave length was opened to the public in 1974. The Gosu Cave, Natural Monument 256, also was opened the public for only 685m of the horizontal cave length, 1,700m, in 1976 in order to preserve its ecological cave environment. The surface of the speleothems in two caves have been turning black due to pollutants after the caves were opened to the public. The degrees of temperature, humidity and partial pressure of carbon dioxide in the caves were related the seasonal variation. Specially, the value of partial pressure of carbon dioxide($CO_2$) in the cave higher in the summer than any other seasons. The partial pressure of $CO_2$ continues to build in the summer because of exceed the self-purification limit in the caves. The value of $CO_2$ variation in the caves was mainly controlled by the amount of visitors. As a result, we have to controlled the amount of visitors to preserve the cave environment.