• The Plant Pathology Journal
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• v.17 no.2
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• pp.101-105
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• 2001

A disease survey on the carnation (Dianthus caryophyllus L.) wilt was conducted during the high temperature period (June through August) and the low temperature period (February through May) in 58 greenhouses of its major cultivation areas, including Pusan, Kimhae, and Changwon in Korea from 1998 to 1999. The disease incidence was averaged 5.4% and 11.9% in the low and high temperature periods, respectively. Severe damage was found in summer with high incidences of around 50% in some greenhouses. Close examination of the symptoms and isolation of the causal agent revealed that there was a new disease different from Fusarium wilt caused by Fusarium oxysporum f. sp. dianthi, which was determined as the stub dieback caused by F. was cetermined as the stub dieback caused by F. graminearum (teleomorph : Gibberella zeae). The stub dieback symptoms involved brown rot of stem that started usually from the portion of cutting without discoloration of inner vascular tissues. Seven out of 38 isolates from the wilted plants were identified as F. graminearum, while the others as F. oxysporum f. sp. dianthi. Mycological characteristics of the stub dieback pathogen including colony color, absence of microconidia, and the shape of macroconidia, were consistent with F. graminearum previously described. This is the first report of the carnation stub dieback in Korea.

• Journal of Bio-Environment Control
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• v.13 no.1
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• pp.56-60
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• 2004

The aphidophagous lady beetle, Harmonia axyridis, is induced to undergo reproductive diapause by low temperature treatment. The diapause of the adult beetle can be maintained without supplying the diet up to 5 months at $4^{\circ}C$. The diapause can be induced any time including during the summer, allowing the beetle to be supplied to the field for the control of aphids through the year. Fecundity and longevity after the reproductive diapause is though to be satisfactory enough for the control of aphids in the field, Methoprene, an analog of reproductive hormone of JH, increases the early fecundity of the beetle.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.854-859
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• 2006

This study aims to evaluate the effect on indoor environment by the application of the shading device on winter season. Therefore, thermal and visual experiments were conducted at two side-by-side mock-Lip test cells which were equipped with the shading device(venetian blind & roll blind) at interior and exterior side of the window. The results of this study are as follows: 1) At night of winter, the shading device can prevent internal heat from going out. 2) Exterior shading device is more effective in winter as well as in summer. 3) At daytime of winter, the shading device can provide the uniformity of illuminance, and the interior shading device is more effective.

• Journal of Climate Change Research
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• v.7 no.1
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• pp.19-29
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• 2016

In this study, the emission intensity calculation method of GHGs was developed by considering the characteristics of the models and time series. The telematics device was installed on the car (OBD-II) to collect information on the operation conditions from each sample vehicle of public authorities. Based on emission intensity of GHGs, it presented a methodology of quantitative comparison of GHGs emission by vehicles. Collected driving information of vehicle was used for operating characteristics analysis of the target vehicle, and it was confirmed different operating characteristics through comparison of the results and previous study. GHGs emission intensity were analyzed considering characteristics of vehicle type by passenger car, van, cargo, and considering characteristics of the time series by summer, winter, and intermediate. From the analysis result, it was calculated GHGs emission intensity based on mileage ($g\;CO_2\;eq./km$) and operating time ($g\;CO_2\;eq./sec$).

• Journal of Environmental Science International
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• v.17 no.8
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• pp.907-918
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• 2008

In order to monitor the impact of high temperature which is seen frequently with climate change, we investigated the monthly change in globe temperature, air temperature, mean radiant temperature and effective radiant heat flow, because the four well reflect thermal radiation from bio-meteorological aspect. Both globe temperature and air temperature showed an increasing trend every month. Compared to air temperature, globe temperature had a wider range of temperature change and was more influenced by meteorological element such as precipitation. Diurnal trends of air temperature, globe temperature and the difference between their temperature had the lowest value before the sunrise and the highest around $1300{\sim}1500$ LST, showing the typical diurnal trends. Globe temperature and the difference between their temperature had a sharp increase around $1000{\sim}1100$ LST, maintained high value until 1700 LST and then reclined, though varied by month. The difference between globe temperature and air temperature was highly dependent on the amount of precipitation and clouds. The duration in which globe temperature was higher than air temperature was the lowest in July. Therefore the amount of precipitation was the most affecting, followed by the amount of clouds and wind. In order to find out the diurnal trends of temperature in city center and city outskirts, we assumed the roof of a concrete build ing as a city center, and the grass-covered observatory of the Gimhae International Airport as city outskirts. The diurnal trends of temperature in the two sites showed a strong correlation. The highest and lowest temperature also had the same trend.

• Journal of Korean Society on Water Environment
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• v.30 no.2
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• pp.119-127
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• 2014

The objective of this study is to evaluate and analyze Sumjin River Basin water environment system. It was necessary to improve the water quality. The data were collected from 2010 January to 2012 December including Water Temperature, pH, DO, EC, $BOD_5$, COD, TOC, SS, T-N, T-P. The data were used to study were required to; Correlation Analysis; Principle Component Analysis; Factor Analysis. The results were as followed. According to correlation analysis on $BOD_5$ against COD, TOC it revealed that the each value of correlation coefficient were 0.715 and 0.719; this means the strength of the relationship is strong. The same analysis on T-P against $BOD_5$, COD, TOC, SS has revealed that the range of the correlation coefficient value fell between 0.482 and 0.608 which means strength of the relationship between them remained normal. Through correlation analysis, it has been found that all elements except T-N have high correlation. The results of principal component analysis to target the overall water quality was extracted to three main components. The cumulative contribution rate is 68.990%. In the case of seasonal water quality, Spring and Summer are extracted to each of four main components. The cumulative contribution rate is 81.515% and 73.550% respectively. Fall and Winter are extracted to each of three main components. The cumulative contribution rate is 65.072% and 72.721% respectively. There is no seasonality in the case of factor analysis. The first common factor is $BOD_5$, COD, TOC, SS, T-P, which were classified. Totally speaking, Sumjin River Basin water system gets highly affected by the nutrient salts, organic matter and suspended solid at the same time.

• Journal of Environmental Health Sciences
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• v.41 no.4
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• pp.259-267
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• 2015

Objectives: This study evaluated the regional and seasonal concentrations of ambient hazardous heavy metals in an industrial complex area in Daegu City. Methods: A total of 64 SPM (Suspended Particulate Matter) samples were collected in non-industrial and industrial areas during 2014 and were analyzed for hazardous heavy metals elements (As, Cd, Mn, Ni, Pb) with ICP after acid extraction. Results: SPM and hazardous heavy metals concentrations showed regional (industrial complex area>non-industrial complex area) and seasonal (spring, winter>fall, summer) variations. All of the hazardous heavy metals were influenced by anthropogenic sources. The pollution index of hazardous heavy metals was very low, showing roughly one-quarter of the level of the air quality guidelines of WHO. The correlation analysis among SPM and hazardous heavy metals indicated that components of non-industrial complex areas were more related to each other than those of industrial complex areas, and the correlation in the winter was higher than in other seasons. Conclusion: It is necessary to control air pollution sources and establish related policy because hazardous heavy metals from industrial areas can influence residential areas.

• Journal of Environmental Science International
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• v.32 no.4
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• pp.243-257
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• 2023

This study was conducted to investigate the distribution characteristics, source identification, and health risk of polycyclic aromatic hydrocarbons (PAHs) present in particulate matter 10 (PM-10), in Gwangju. PM-10 samples were collected from September 2021 to August 2022 from three sampling sites, one located in each of the following areas: green, residential, and industrial. The average concentrations of PAHs were found to be higher in the industrial area (9.75±6.51 ng/㎥) than in the green (6.90±2.41 ng/㎥) and residential (6.74±2.38 ng/㎥) areas. Throughout the year and across all sites, five-ring PAHs accounted for the largest proportion (29.8-34.5%) of all PAHs. The concentrations of PAHs showed distinct seasonal variations, with the highest concentration observed in winter, followed by autumn, spring, and summer. Source apportionment analyses were performed using diagnostic ratios and principal component analyses, which indicated that coal/biomass combustion and vehicle emissions were the primary sources of PAHs in PM-10. The incremental lifetime cancer risk was estimated for all age groups at all sampling sites, and the results revealed a much lower risk level than the standard acceptable risk level (1×10^-6).

• Journal of Environmental Science International
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• v.33 no.5
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• pp.283-296
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• 2024

This study examined the distribution of airborne metals concentrations and conducted a risk assessment in PM-10 in Gwangju from 2014 to 2022. There were a total of six points, and the concentration of heavy metals at each point was highest in the order of Pyeong-dong(1.5472 ㎍/m³ ) > Nongseong-dong(1.2093 ㎍/m³ ) > Geonguk-dong(1.0100 ㎍/m³ ) > Duam-dong(0.9684 ㎍/m³ ) > Seo-dong(0.9515 ㎍/m³ ) > Nodae-dong(0.8321 ㎍/m³ ). In recent years, the concentration of heavy metals in the atmosphere has generally risen, accompanied by an increase in heavy metals in the soil. The average seasonal concentrations were in the following order: spring(1.4448 ㎍/m³ ) > winter(1.2939 ㎍/m³ ) > fall(0.8303 ㎍/m³ ) > summer (0.5928 ㎍/m³ ). The atmospheric heavy metals most correlated with PM-10 were Ca(0.69), Fe(0.62), Al(0.62) and Mg(0.60). Within the acceptable risk level (1.0E-06) set in this study, heavy metals in the atmosphere were found to have the most excess cancer risk, and the integrated non-cancer risk was as low as 1 or less.

• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.230-236
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• 2021

Changes in greenhouse temperature and solar radiation due to fogging and shading were monitored during hydroponics in high temperature in summer season. Experiment 1 consists of four treatments, namely, Control, Shading, Fogging, and Fogging + Shading based on sunny days August. For Experiment 2, two melon cultivars of 'Dalgona' and 'Sopoong gaza' were cultivated in summer of 2020 using Fogging + Shading with the best result for temperature reduction effect from Experiment 1. As a result of Experiment 1, the effect of Fogging + Shading on temperature reduction was apparent where the inside was about 4℃ (as the lowest temperature) lower than the outside. Fogging + Shading showed the inside was 2-4℃ lower than the outside, and Fogging or Shading treatments had little difference, compared to the Control where the internal temperature of greenhouse was 3-4℃ higher than the external. For solar radiation changes between greenhouse inside and outside, the internal change was in a similar pattern between Fogging and Control, and between Shading and Fogging + Shading, respectively. In case of the Fogging treatment (similar with the Control) only the effect of solar radiation reduction as influenced by plastic greenhouse covering materials was examined. The Fogging + Shading had a very similar change in solar radiation to the Shading. Based on these results, Experiment 2 was conducted in summer of 2020 and resulted in a temperature reduction effect of about 3.9℃ according as the inside of air-conditioned greenhouse was kept 32.4℃ when the maximum temperature of the outside reached 36.3℃ in August during the cultivation period. In addition, the quality of melon fruit was good (1.3-1.5 kg of fruit weight, 12.6-13.3 of soluble solids content. In the case of using Fogging + Shading cooling treatment, it can bring about the effect of reducing the temperature during the high temperature in summer, and normal growth of melon and fruit harvesting were possible.