• International Journal of Industrial Entomology and Biomaterials
• /
• v.18 no.2
• /
• pp.97-103
• /
• 2009

Sericulturists in the vicinity of Bangalore city irrigate their mulberry gardens with Vrishabhavathy stream water, which is polluted with domestic and industrial wastes from the city. To investigate the effect of pollutants on silkworm crops, a detailed field survey was conducted to study the cocoon yield pattern of the crops raised on mulberry irrigated with wastewater as against irrigation by bore/open wells. The villages along the stream were grouped into five test batches at about a distance of $5{\sim}8$ km from each other. The seasonal yield data with relevant information were collected through questionnaires from 117 rearers using stream water and 35 rearers using bore/open wells, the latter serving as control group. The average yield for 100 layings was 46 to 57 kg in the control group whereas in test groups, it ranged between 34 to 51 kg in the first test group and 22 to 38 kg in the rest. The difference in yield was $9{\sim}19$ kg depending on the season between control and test batches. In summer, this difference was higher, with high co-efficient of variation in test groups ($33{\sim}52$%). Further, water, soil and leaf samples were collected from selected rearers and were analyzed for zinc, copper, iron, lead and nickel. Results indicated significantly higher contents of these metals in samples from gardens using wastewater when compared control samples. Significantly (p<0.05 & p<0.01)) higher levels of zinc ($24{\sim}122$ ppm) and iron ($208{\sim}683$ ppm) were noticed in mulberry leaves during summer followed by winter and rainy season. The significance of high content of heavy metals in mulberry leaves and cocoon yield pattern of this area in relation to the quality of irrigation water is discussed.

• Journal of Korean Society of Forest Science
• /
• v.80 no.4
• /
• pp.351-359
• /
• 1991

Annual ring characteristics of pinus thunbergii grown in several air-polluted areas were investigated by soft X-ray densitometry. Ring width, maximum density and relative difference between maximum and minimum density(abbreviated to DD) were generally decreased after the beginning of operation of the factories at the vicinity of the pollution sources. Especially at the nearest areas of the industrial complex, those were distinctly decreased, and the changes, either increases or decreases, in percentage of latewood and minimum density could not be explained by the air pollution dosages. Ring width, maximum density and DD were being more apparently decreased after 5 years than those for 5 years after the beginning of operation, and also the rate of decrease was increased from after 5 years after the beginning of operation, and the rate of decrease of ring width was the highest of all. It was inferred that ring width, maximum density and DD of Pinus thunbergii could be used as indicators to detect the growth damage by air pollution.

• Journal of the Korean Society of Costume
• /
• v.58 no.1
• /
• pp.90-103
• /
• 2008

This study aims to examine the current state of wearing working clothes for the workers who work in Electric Technology Division, Korea Railroad Corporation, to identify inconveniences and problems in relation to the working clothes, and based on the examination, to find a way to improve them, creating a design of summer working clothes that will have more advanced functionalities including activity adaptability and comfort. Survey was conducted through direct observation and interview for Electric Railway Power Team. A total of 352 copies were collected and analyzed. Based on the results of questionnaire, an experimental clothes, the functionality of which has improved in terms of design, material, and patterns, was created. The followings are the results of the study. Easy activity, design, and comfort are required as functions of working clothes. In design related questions, the survey shows high dissatisfaction in the color of existing working clothes, and preferred colors are dark blue and gray. With regard to the method of zipping up the front side, zippers are preferred. Although many pockets on the existing working clothes have high satisfaction, dissatisfaction to pocket format is high. In material related questions, lower dissatisfaction is indicated for the sense of touch, ventilation and sweat absorption. It is shown that the areas frequently polluted include the lower part of pocket, the edges of sleeves and elbow areas on the jacket. The frequently polluted area of the trousers include knee areas, the edges of pants and buttocks. With regard to the areas where the workers felt discomfort when motion, discomfort is highly indicated with armpits and back on the jacket. Also discomfort is highly indicated with crotch, buttocks and knee areas on the trousers. In material related questions, lower dissatisfaction is indicated for the sense of touch, ventilation, sweat absorption.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.2 no.2
• /
• pp.110-116
• /
• 1997

Changes of fish species composition were analyzed using seasonal samples collected from Lake Shihwa and adjacent coastal water from October 1995 to August 1996. Pelagic clupeids, Cynoglossus joyneri and Johnius belengerii predominated in abundance in the adjacent coastal water. In the lake, clupeids, gobies and freshwater Carassius carassius were collected in autumn. The clupeids, unable to overwinter in the open water, disappeared after winter. The gobies and C. carassius were also disappeared in spring except a few number of Acanthogobius hasta. A large number of Tridentiger trigonocephalus and Eleotris oxycephala were collected in summer, supposed to move into the lake during the exchange of water in lake and sea water. However, they were all died in the middle of August. The concentration of ammonium-nitrogen was higher than 2 mg/l, which was higher than 50% lethal concentraton in other fishes. Increase in temperature and pH in spring may elevate the toxicity of ammonium to fish. We discussed the effect of the other factors of the polluted water in the lake on the disappearance of fish.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.10 no.5
• /
• pp.31-39
• /
• 2007

This study was carried out to evaluation the recycled waste soils from construction site for planting soil. For this purpose, the concentrations of polluted materials and the physico-chemical properties were measured at recycled soil samples of an industrial waste treating company in the Metropolitan landfill area. The concentrations of polluted materials did not exceed to the standard critical levels of soil pollution in all analyzed items. The measures of the samples soil texture (loamy sand), bulk density (1.09~1.32g/$cm^3$), saturated hydraulic conductivity ($1.6{\times}10^{-3}{\sim}1.8{\times}10^{-3}$cm/sec), solid phase distribution (0.4~0.5$m^3/m^3$), porosity (0.5~0.6$m^3/m^3$), Ex. $K^+$ (1.0~1.2cmol/kg), Ex. $Mg^{2+}$ (0.2~0.6cmol/kg) were identified as not worse than those of conventional planting soil. But the sample soils have serious problems for planting soil such as high levels of pH (9.6~11.5), EC (0.78~1.84ds/m) and Ex. $Ca^{2+}$ (25.6~34.5cmol/kg), low level of organic matter (0.2~0.3%). It is required to improve pH, EC and Ex. $Ca^{2+}$ of sample soils. Consequently, the results suggested a high potential of recycling of the wastes soils for planting soil.

• Journal of Environmental Health Sciences
• /
• v.38 no.6
• /
• pp.472-481
• /
• 2012

Objectives: This study aims to investigate the AD (allergic diseases: asthma, allergic rhinitis and atopic dermatitis) prevalence among elementary schoolchildren in an industrial city, Ulsan, and identify major environmental risk factors associated with AD prevalence. Methods: Data on the physician-diagnosed prevalence over the past 12 months and potential risk factors of AD were collected through a questionnaire from a 2009-2010 survey of 4,067 schoolchildren living in different urban environments. The logistic regression analysis was performed to assess differences in AD prevalence among the areas and to determine which environmental factors impacted AD. Results: Our survey results showed that the AD prevalence rate ranged between 26.2% and 35.9%. Children living in polluted areas (near industrial and central urban areas) had about a 10% higher prevalence of AD than did those living in coastal or suburban residences. The Chi-Square test demonstrated that this local difference was statistically significant before and after adjustment of major confounders such as parental AD history and parental education. The results of the logistic regression analysis showed a statistically significant association between several environmental factors (ventilation in winter, odor conditions and exposure to traffic smoke, and outdoor $PM_{10}/O_3$ pollution) and the prevalence of AD found by multivariate model after adjusting confounders. Conclusion: These results suggest that local differences in AD prevalence are significantly associated with outdoor environmental factors. Although there are likely to be other risk factors for AD, living in a polluted area and exposure to high levels of air pollutants can contribute to an increased risk of childhood AD.

• Journal of Korean Society on Water Environment
• /
• v.33 no.3
• /
• pp.334-340
• /
• 2017

A pilot-scale electrodialysis system was designed and constructed to treat groundwater polluted with arsenic and manganese. Synthetic groundwater, in which some amount of arsenic and manganese was added to make 500 mg/L of Mn and $50{\mu}g/L$ of As, was used as a feed for the ED system. The limiting current density, linear water velocity, applied voltage, and membrane surface area were investigated to obtain efficient and economic operation of the ED system. The linear water velocity was increased 0.74 cm/s to 11 cm/s based on evaluation of limiting current density. The water quality of diluate for 85 minutes of operation was satisfied with water quality criteria for drinking water using the ED system with 14 pairs of ion exchange membranes. The increased membrane pairs to 21 and 42 pairs were very effective to reduce conductivities of the diluate. The operation cost of the ED system was assessed using specific energy consumption, which was $1.065{\sim}1.2kWh/m^3$. Considering low salt concentrations of the groundwater, improvement of the ED system are required to increase current utilization and to apply low voltage while the ED system was applicable to produce drinking water.

• Korean Journal of Ecology and Environment
• /
• v.42 no.3
• /
• pp.303-316
• /
• 2009

Benthic macroinvertebrate communities collected from eight different streams in South Korea were analyzed to compare community and biological indices across different levels of water pollution. The Self-Organizing Map (SOM) was utilized to provide overview on association of the proposed indices. The sample sites were accordingly clustered according to the gradient of pollution on the SOM. While the general trends of the indices were commonly observable according to different levels of pollution, the detailed differences among the indices were also illustrated on the SOM. The conventional diversity and evenness indices tended to be high even though the water quality state was poor representing relatively weak gradient at polluted sites, while the index presenting the saprobic degree such as family biotic index showed the stronger gradient at the polluted area and was robust to present the gradient. Our results also confirmed the general characterization of two indices: The Shannon index is more strengthened by the number of species occurring at the sample sites, while the Simpson index is more influenced by the degree of evenness among the species. The patterning based on the SOM was efficient in comparatively characterizing the proposed indices to present ecological states and water quality.

• Applied Chemistry for Engineering
• /
• v.19 no.4
• /
• pp.445-451
• /
• 2008

In order to regenerate the activated carbon polluted by volatile organic compounds (VOCs) using microwave, adsorption and desorption characteristics of benzene over activated carbon (AC) coated with insulating materials were investigated. Physical characteristics of activated carbon and insulator-coated ACs were investigated by means of $N_2$ gas adsorption and scanning electron microscopy (SEM). The amount of VOC adsorbed showed a positive relationship with the specific surface area of the ACs, and spark discharge over insulator-coated ACs did not occur. Potassium silicate (PS) was the best binder for coating of insulating materials on AC. Amount of benzene desorbed by microwave irradiation was dependent on output power of microwave. Nearly same performance was obtained even though the adsorption-desorption operation under microwave irradiation was repeated 5 times. Finally, it was known that the microwave heating was a very effective mean for regenerating the polluted AC.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.20 no.5
• /
• pp.504-510
• /
• 2014

In this study, physico-chemical properties and pollution degree of surface sediments collected at 5 stations(S1~S5) of Incheon H wharf in March 2014 were investigated. From particle size, surface area, XRD and XRF analyses, the sediment samples consisted of similar oxides and minerals. Considering total score of COD, AVS and IL, pollution level ranged between 2 and 3 based on domestic standards. In case of heavy metal contamination, Cd, Ni and Pb were classified as moderately polluted by USEPA standards. However, Cu, Zn and Cr were classified as heavily polluted. With geoaccumulation index value($I_{geo}$), Cd contamination was estimated as class 3. In addition, the calculated enrichment factors of Cd, Pb and Zn were exceeded a value of 1. Site S4 was high as 3.1 in total enrichment factor.