• Journal of Preventive Medicine and Public Health
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• v.17 no.1
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• pp.65-73
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• 1984

To assess the status of industrial injuries, a large scale textile company located around Taegu city was selected. And it was investigated from January 1981 to December 1982. After the department for workers safety was established, frequency rate of injury was 9.70 in 1981 and 4.15 in 1982, incidence rate per 1,000 workers was 27.11 in 1981 and 12.96 in 1982, and then, intensity rate was 0.33 in 1981 and 0.01 in 1982. The average duration of working loss was 36.64 days in 1981 and 3.34 in 1982. The incidence rate per 100 workers was 2.3 in annual average, 2.7 in men and 2.0 in women. The monthly incidence rate per 1,000 workers was highest as 3.6 in June; daily incidence rate, lowest as 1.8 on Sunday; and the highest as 14.7 from 10 to 12 o'clock in a day. The frequency by injured parts of body was highest as 42.3% on finger and 14.4% on the other part of hand, and the lower extremities as 14.4% followed. According to the kind of injuries, the laceration was the highest as 46.1%, the next was contusion as 15.4%, and the third was superficial injuries as 6.7%, According to the cause of injuries, the machinery accidents showed the highest as 47.1% and the accidents due to hand tool followed as 16.3%. By underlying cause of injuries, the environmental factors were 13.5% and the human factors 86.5%. The psychologic factors among human factors were the most common as 60.6%.

• Korean Journal of Organic Agriculture
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• v.9 no.2
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• pp.101-115
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• 2001

Nitrogen applied as fertilizer for crop production is partly absorbed by plant , and the remaining nitrogen in soil might be leached out through complicated processes to the subsoil layer Especially, NO$_3$-N in leachate causes environmental pollution. The purpose of this study was focused on understanding of uptake of nutrients by plants, the behaviors of nutrients in soil and the possibility of leaching loss when nitrogen fertilizer and completely decomposed compost were applied. Lysimeters(Volume 0.15㎥, Diameter 62cm, Height 62.8cm) were installed for collecting leachate in the Jeju volcanic ash soils. Lysimeter study consisted of thirteen treatments : fallow, fallow with weeding, cropping without fertilizer and compost, three N fertilizer soil surface applications(16, 32, 64kg/10a), three N fertilizer and compost soil surface applications(16+800, 32+1600, 64+32kg/10a), two water dissolved N fertilizer applications(16, 32kg/10a), and low and high plant densities. N fertilizer was applied as urea. The growth of com(preceding crop) and potatoes(succeeding crop) and leaching loss were determined during the experimental period. The results obtained were summarized as follows ; With Increased N, pH of leachate tended to decrease and NO$_3$-N concentration of leachate increased. NO$_3$-N leaching loss was remarkably greater in soil from the bare plot without fertilization and the weed control than from plots with medium N rate and was least in the cropping plot without fertilization. NO$_3$-N concentration in leachates from the water dissolved N fertilizer application plots was 64% of that from the soil surface application plots. The concentration of Ca and K ions and the leaching loss of these ions were least from the cropping plot without fertilization and were greatest from bare plots(T1 and T2) without fertilization. The proportion of leaching and residual N in soil increased as N rate increased indicting that higher N rates increase the possibility of N leaching to subsoil layer The proportion of N leaching losses was lower at the low N rate and the high plant density. In future, fertilization prescription which can maximize fertilizer use efficiency and minimize the pollution of ground water will be needed for conserving the environments.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.2
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• pp.119-130
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• 2000

Mn, Zn, Cd and Pb in shells of Littorina brevicula, which lives ubiquitously in intertidal zone around the Korean coast, were analyzed to determine the relationship between metal levels in its shell, ambient seawater and its tissue. Periwinkles and seawater samples were collected from 38 sites along the Korean coast in January 1997. Mn contents in shells of this organism show the range of 7.0 ${\mu}g$/g-211 ${\mu}g$/g (mean 59 ${\mu}g$/g) and are the lowest in northern east coast but high in western south and west coast. Close relationship between Mn contents in shells and metal levels both in seawater and in tissues indicates that Mn in shell might be incorporated from ambient seawater by a biological process. Although the contents of Cd in shells did not reflect the distribution of total Cd in seawaters and they were very low compared to those in tissues, they followed spatial gradient of contents in tissues. However, the spatial distribution of Zn contents in shells accords neither ambient seawater nor tissues, while it is negatively correlated with the contents of Na in shells. This fact suggests that Zn contents might be controlled by salinity of ambient seawater. On the contrary, Zn contents in highly polluted sites near Onsan Bay show generally higher levels than other sites. The contents of Pb show the range of 0.1 ${\mu}g$/g-17.5 ${\mu}g$/g (mean 1.01 ${\mu}g$/g) and the highest in sites near Onsan Bay. Although the spatial distribution of shell Pb does not follow those of tissue, Pb in shells of Littorina brevicula may be controlled both by shell secretion process and by Pb levels in ambient seawater because the contents of Pb in the shell decrease steadily with growth and vary with levels of Pb in ambient seawater.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.3
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• pp.190-198
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• 2006

Radiation use efficiency (RUE), the amount of biomass produced per unit intercepted photosynthetically active radiation (PAR), constitutes a main part of crop growth simulation models. The objective of the present study was to evaluate the variation of RUE of rice plants under various nitrogen nutritive conditions. from 1998 to 2000, shoot dry weight (DW), intercepted PAR of rice canopies, and nitrogen nutritive status were measured in various nitrogen fertilization regimes using japonica and Tongil-type varieties. These data were used for estimating the average RUEs before heading and the relationship between RUE and the nitrogen nutritive status. The canopy extinction coefficient (K) increased with the growth of rice until maximum tillering stage and maintained constant at about 0.4 from maximum tillering to heading stage, rapidly increasing again after heading stage. The DW growth revealed significant linear correlation with the cumulative PAR interception of the canopy, enabling the estimation of the average RUE before heading with the slopes of the regression lines. Average RUE tended to increase with the increased level of nitrogen fertilization. RUE increased approaching maximum as the nitrogen nutrition index (NNI) calculated by the ratio of actual shoot N concentration to the critical N concentration for the maximum growth at any growth stage and the specific leaf nitrogen $(SLN;\;g/m^2\;leaf\;area)$ increased. This relationship between RUE (g/MJ of PAR) and N nutritive status was expressed well by the following exponential functions: $$RUE=3.13\{1-exp(-4.33NNNI+1.26)\}$$ $$RUE=3.17\{1-exp(-1.33SLN+0.04)\}$$ The above equations explained, respectively, about 80% and 75% of the average RUE variation due to varying nitrogen nutritive status of rice plants. However, these equations would have some limitations if incorporated as a component model to simulate the rice growth as they are based on relationships averaged over the entire growth period before heading.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.625-639
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• 2019

Microplastics are one of the substances threatening the marine ecosystem. Here, we summarize the status of research on the effect of microplastics on marine life and suggest future research directions. Microplastics are synthetic polymeric compounds smaller than 5 mm and these materials released into the environment are not only physically small but do not decompose over time. Thus, they accumulate extensively on land, from the coast to the sea, and from the surface to the deep sea. Microplastic can be ingested and accumulated in marine life. Furthermore, the elution of chemicals added to plastic represents another risk. Microplastics accumulated in the ocean affect the growth, development, behavior, reproduction, and death of marine life. However, the properties of microplastics vary widely in size, material, shape, and other aspects and toxicity tests conducted on several properties of microplastics cannot represent the hazards of all other microplastics. It is necessary to evaluate the risks according to the types of microplastic, but due to their variety and the lack of uniformity in research results, it is difficult to compare and analyze the results of previous studies. Therefore, it is necessary to derive a standard test method to estimate the biological risk from different types of microplastics. In addition, while most of the previous studies were conducted mostly on spheres for the convenience of the experiments, they do not properly reflect the reality that fibers and fragments are the main forms of microplastics in the marine environment and in fish and shellfish. Furthermore, studies have been conducted on additives and POPs (persistent organic pollutants) in plastics, but little is known about their toxic effects on the body. The effects of microplastics on the marine ecosystems and humans could be identified in more detail if standard testing methods are developed, microplastics in the form of fibers and fragments rather than spheres are tested, and additives and POPs are analyzed. These investigations will allow us to identify the impact of microplastics on marine ecosystems and humans in more detail.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.56-62
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• 2010

Quality characteristics such as alcohol, acid, and sugar contents of takju brewing mashes prepared using several yeasts were investigated during 12-days of fermentation. Among the yeasts examined, S. cerevisiae led to the highest level of ethanol (10.2-13.4%) and total minor alcohols (0.729-0.831 mg/mL). Regardless of the yeasts used, the acidity showed drastic changes (pH from 3.4-4.2 down to 2.4-2.7) during the first 2 days, and displayed negligible changes from day 4. The total acid contents rapidly increased to the first 4 days of fermentation and leveled off from 4 to the end of fermentation period. The common organic acid components were lactic, succinic and acetic acids. The total and reducing sugar contents varied depending on the yeasts used, with mashes prepared using S. coreanus and S. rouxii producing the maximum total sugar contents (5.43-5.5%) at the end of fermentation. The reducing sugar showed its maximum (7.53-14.89%) at day 2, after which it decreased to its minimum levels (3.04-4.52%). The common free sugar components were glucose and fructose, while S. ellipsoideus led to a higher free sugar level (0.35-5.29%).

• Journal of Korean Society for Geospatial Information Science
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• v.22 no.3
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• pp.57-69
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• 2014

As of 2013, Korean population density is 505 persons per $1km^2$ and is ranked 3rd place in the most densely populated countries exception of city-states. It shows clearly the population is concentrated in the city area. To fulfil this urban concentration population demand, the enlargement and complexation of buildings, subway and other underground spaces connection tendency has been intensified, and it is need to construct the indoor spatial information DB as well as the accurate indoor surveying DB to promote people's safety and social welfare. In this study, Sadang station and Incheon National Airport were aimed for the construction of Wi-Fi AP location DB and RadioMap DB by collecting the indoor AP raw datas by using mobile device and those collected results were ran through the process of verification, supplementation, and analyzation. To evaluate the performance of constructed DB, 10 points in Incheon Airport- 3rd flr in block A, and 9 points in Sadang station-B1 were selected and calculated the estimated points and ran evaluation experiment using survey positioning error, which is distance between real position and the estimated position. The result shows that Incheon international airport's average and standard deviation was separately 17.81m, 17.79m and Sadang station's average and standard deviation was separately 22.64m, 23.74m. In Sadang station's case, the areas near the exit has low performance of surveying position due to fewer visible AP points than other areas. As total datas were examined except those position, it was verified that the user's location was mapping close position in surveying positioning by using constructed DB. It means that constructed DB contains correct Wi-Fi AP locations and radio wave patterns in object region, so it is considered that the indoor spatial information service based on constructed DB would be available.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.172-183
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• 2017

Germinated brown rice (GBR) has received considerable attention over the last decade as a means of enhancing the nutritional value and health-promoting functions of rice. The effect of germination on the physicochemical and textural properties of brown rice (BR) was investigated in different rice varieties (Samkwang, Misomi, Chindeul, and Hyeonpum). Cooking properties, such as water absorption, expanded volume, and soluble solids were significantly increased by germination in all rice varieties. Textural properties (hardness, toughness, adhesiveness, and stickiness) of cooked samples were determined using a texture analyzer. Hardness and toughness were decreased by germination, whereas stickiness and adhesiveness increased significantly. These results revealed that germination leads to improvements in the cooking and eating properties of BR. In Rapid Visco Analyzer (RVA), significant reductions were observed for peak viscosity, break down, set back, and final viscosity after germination. Although the amylose content of Misomi was slightly decreased by germination, that of other varieties increased significantly. Germination induced no noticeable change in the average chain length of amylopectin in Misomi, Chindeul and Hyeonpum, but led to a significant increase in Samkwang.

• Journal of Dairy Science and Biotechnology
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• v.30 no.1
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• pp.23-30
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• 2012

This study was carried out to investigate the quality characteristics of yoghurt with varying contents of Sanmeoru (Vitis amurensis Ruprecht) wine (SW). Yoghurts were fermented with 2 kinds of lactic acid bacteria (Streptococcus thermophilus and Lactobacillus bulgaricus; Yo-$MIX^{TM5}505$, Danisco, Denmark). The changes in quality characteristics were investigated during fermentation and storage, and anthocyanin composition was analyzed after fermentation. The pH decreased in all treatments, while titratable acidity and viscosity gradually increased during fermentation. The viscosity of the yoghurt with 5.0% cultured SW added was higher than in other groups. The viable counts of lactic acid bacteria gradually increased during fermentation. The sample of the 5.0% cultured SW-yoghurt was higher than that of the other groups. The pH slowly decreased during the storage period; this was lower in the control yoghurt than in the yoghurts containing SW, and the changes of titratable acidity in the samples containing 5.0% and 30.0% cultured SW were lower than that in the yoghurt containing 1.0% cultured SW and in the control. The change in viscosity and number of viable cells during storage was higher in the yoghurts containing SW than in the control group. The levels of anthocyanin increased with the SW content in the yoghurt. Sensory scores for taste of the yoghurt with 1.0% added SW was significantly higher than for the other groups. Yoghurt with added SW kept at $4^{\circ}C$ for 12 days retained its quality characteristics fairly well.

• Journal of Animal Science and Technology
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• v.48 no.5
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• pp.699-708
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• 2006

Ground rice, barley and corn were fed separately to the ruminally cannulated Hanwoo (Korean native cattle) for comparing their in situ and in vitro degradabilities, microbial growth, pH and gas production. It has been found that nearly all the dry matter (DM) and organic matter (OM) in barley and rice disappeared during 24 hr suspension in the rumen, but those in corn were only reduced by around 67%. Water soluble DM and OM fractions(‘a’), ranked from highest to lowest was corn, then rice and finally barley, but the order was reversed for content ‘b’, degradable fraction during time ‘t’. Judging by the degradation parameter of ‘b’ fraction, degradation rates per hour of DM and OM for barley were 38.3% and 37.2% respectively, significantly higher than those for rice (7.7% and 5.6%) and corn (4.1% and 1.3%). In general, results obtained from in vitro degradability of DM and OM were lower than those from in situ trials, but the ranking order of degradability was in agreement between both trials. In particular, ground rice has relatively lower in vitro microbial growth than corn or barley, but exhibited higher gas production. In addition, in vitro microbial growth of ground rice increased with up to 12 hr of incubation period, thereafter experienced a decrease with extended incubation time. pH of in vitro solution of rice decreased following 9 hr of incubation but gas production increased rapidly during the same period. From the results of DM and OM degradabilities and pH changes of in vitro solution with incubation time, it is concluded that rice represents a good source of energy for stability of rumen fermentation.