• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.295-300
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• 2012

The purpose of this study was to analyze microbiological hazards for plants, cultivation environments and personal hygiene of perilla leaf farms at the harvesting stage. Samples were collected from three perilla leaf farms(A, B, C) located in Gyeongnam, Korea and tested for sanitary indications, fungi and pathogenic bacteria(Escherichia coli O157:H7, Listeria monocytogens, Salmonella spp., Staphylococcus aureus and Bacillus cereus). As a result, total bacteria and coliform in perilla leaf were detected at the levels of 4.4~5.2 and 3.4~4.3 log CFU/g, respectively, but E. coli was not detected in all samples. Among the pathogenic bacteria, B. cereus(perilla leaf: 2.0~2.4 log CFU/g, stem: 1.4~2.1 log CFU/g, water: 0.7 log CFU/ml, soil: 4.2~5.0 log CFU/g, hands: 3.0 log CFU/ hand, gloves: 2.1~2.4 log CFU/100 $cm^2$, glothes: 1.5~2.8 log CFU/100 $cm^2$) and S. aureus(3.4 log CFU/hand) were detected in all samples and worker's hand from farm A, respectively. However, other pathogenic bacteria were not detected. This study demonstrates that perilla leaf at the harvesting stage was significantly contaminated with microbial hazards.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.305-310
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• 2001

The purpose of this study is to calculate delay damages for contractors. The study has been performed by investigation of delay cost occurrence status and the analysis of subway construction cases. The results of this study are as follows: 1. Delay cost( 1day) equivalent to $0.005\%$ of total construction cost by analysis case studies. 2. Including bank interest, dealy cost is analysed as the following; $1.1\~9.2\%$ of total construction cost in part extension period, $3.3\~11.0\%$ of total construction cost in total extension period. 3. In comparison between liquidated damages and delay cost, liquidated damages account for average 20.1 times of delay costs. 4. Acceleration cost will be calculate on the basis of delay cost calculation method. In the result of this method, acceleration cost is equal to delay cost at least or must be large than delay cost

• Korean Journal of Environmental Agriculture
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• v.26 no.3
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• pp.233-238
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• 2007

To assess pollutant loads in Nakdong river from highland agriculture in Kyungbuk province we. analyzed water qualities such as BOD, COD, T-N, T-P and SS in year 2005. BOD values in rainy period (June and July) were relatively higher than those in dry period, and those in 4 sites among 17 sites ranged from 10.71-19.25 mg/L which exceeded water criteria (8 mg/L) for agricultural use. COD values showed similar trends like BOD values. These trends might be caused by outflow of nutrients applied in agricultural lands. T-N content ranged from 0.1 to 14 mg/L. Those in lower reaches of stream were greater in those in upper stream. Compared to T-N contents during non-farming season, T-N content in farming season were higher. These phenomenon could be due to continuous input of nutrients from small watercourses. Averaged T-P content in lower stream during farming season was 0.4 mg/L, which was eight times higher than the limiting level for algae occurrence (0.05 mg/L). BOD, T-P, T-N loads from alpine agricultural practices were 12.25 $kg/km^2{\cdot}day$, 0.55 $kg/km^2{\cdot}day$ and 32.35 $kg/km^2{\cdot}day$, respectively. These values were greater than those from forestry. Therefore, Best management Practices (BMP) for alpine agricultural field are needed to reduce pollutant loads in Nakdong river.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.4 no.3_4
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• pp.113-120
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• 1971

In 1971, about 150,000 fingerlings of grass and silver carps were produced and distributed from the Fishculture Laboratory of Pusan fisheries College. The adults Were those transplanted from Japan in 1963. Findings during the process of this production are summarized as following : 1. Brood fish must be handled with a great care during the catching, hormone injection and maturity inspection so as the fish are not injured, otherwise, the eggs would not mature perfectly. Scale fall also affects significantly. 2. The amount of pituitary to be injected is preferable to be 2 to 3 times or more in donor's body weight to obtain good results. 3. The eggs should be spawned or stripped and inseminated as soon as mature. If the spawning is delayed the eggs become overmature and the hatching rate decreases significantly. 4. The water once used for the incubation of eggs should not be reused. The eggs under hatching process were melted away when water once used for incubation was reused. 5. A great care must be paid to keep water in quality when the net cage culture system is employed for raising fry or early fingerlings of Chinese carps. The best method to keep water in quality is to supply water in the cage continuously through a pipe or hose. 6. Heavy outbreaks of Spirogyra occured when clear well water was supplied into the cage, and a great number of fry or fingerlings were trapped or entangled resulting in a significant decrease of fish under rearing. It was prevented when moderately bloom-ed pond water was supplied into the cage. 7. Silver carp fry are usually captured and transported in the cool season because they can not be handled in the warm season owing to a high mortality, but cage cultured small size fingerlings ranging from 1.5 to 2 cm in total length are easily handled and transported even in the hot summer season, thus it enables the fish farmers to start growing them one season earlier.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.399-405
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• 2011

In this study, we evaluated the fruit quality indices and the incidence of physiological disorders of Korean new pear cultivar 'Whasan' to determine appropriate harvest time for exportation and to enhance storability and shelf-life of the fruits during simulated exportation and extending market environment under different temperature conditions. In the experiment of simulated exportation headed for North America including Canada and U.S.A., the fruits transported at $1^{\circ}C$ showed less weight loss than those of $5^{\circ}C$. Market temperature appeared as a key factor for keeping freshness of exported pear fruits rather than transportation temperature. Quality factors such as high flesh firmness and low incidence of fruit rot and physiological disorders including core breakdown and pithiness were attained at the fruits maintained at $18^{\circ}C$ when we compared with $25^{\circ}C$. The fruits of harvested early maturity at 135 day after full bloom showed 28.6 N of flesh firmness when the fruits stored at $1^{\circ}C$ of transportation and $18^{\circ}C$ of market temperature, while the fruits progressed $5^{\circ}C$ of transportation and $25^{\circ}C$ of market temperature dropped to 24.2 N during 30 days of shelf life. Also, a high incidences of physiological disorders and of fruit decay rates were obvious in the fruits distributed at $25^{\circ}C$ were observed approximately two times higher than the those of $18^{\circ}C$. Therefore, temperature management during marketing resulted as an important point for maintaining fruits quality in the process of pear fruit exportation.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.1
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• pp.16-24
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• 2010

Effect of flooding on the desalting efficiency and the growth of sudan grass, barnyard grass, sesbania and corn was studied in a sandy soil of the Iweon reclaimed tidal land. Flooding plots were treated by 400 (one time flooding), 800 (two times flooding), and 1,200 mm(three times flooding) of water, respectively, and then soil salinities of the treated plots were compared with salinity of the control plot (not flooded) for estimation of desalting effect. Desalting ratio of 1,200 mm treatment was 78.3% for depth 0-20 cm, 70.5% for depth 20-40 cm and 60.8% for depth 40-60 cm, and then the soil salinity reached at 3~6 dS $m^{-1}$. Consequently, it was considered that sandy saline soil was satisfactorily desalted for upland crops to be cultivated by 1,200 mm flooding, but insufficiently desalted by 400 mm and 800 mm flooding because of high salinity ranged 5~14 dS $m^{-1}$ even after flooding treatment. In addition, it was estimated that soil salinity should be controled lower than 7.7 dS $m^{-1}$ in order to obtain more than 80%of crop emergence when four crops are simultaneously cultivated by inter- or mixed cropping in a field. Dry matter yields (kg $10a^{-1}$) was 1,068 for sudan grass, 696for barnyard grass, 1,426 for sesbania, and 1,164 for corn by 1,200 mm flooding treatment, but only 46.8~74.3% by 800 mm flooding treatment and 2.9~25.5% by 400 mm flooding treatment. Therefore, it is concluded that the flooding treatment more than 1,200 mm is necessary for satisfactory desalinization in order for the low salt tolerance crops to be cultivated in the sandy reclaimed tidal land.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.429-439
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• 2013

This study was conducted to identify the relationship between environmental factors and algal bloom, and provide information for efficient management based on the results of monitoring the environmental parameters and algal diversity in the Jundai reservoir from March 2011 to October 2013. Little change in the weather conditions was observed during the study period except for a slight decrease in rainfall. Concentration of TN and TP in the reservoir exceeded water quality standards for agriculture and significant correlation between algal growth and environmental factors was observed. Phytoplankton in Jundai reservoir included 6 classes, 40 genus, 62 species, and the phytoplankton abundance was in the range of $1.3{\times}10^4{\sim}2.8{\times}10^6$ cells $mL^{-1}$. The annual average of phytoplankton abundance and Chl-a gradually decreased as TN and TP concentrations decreased. Overall Anabaena sp., Oscillatoria sp., and Microcystis sp. were the dominant species in Jundai reservoir. As the water temperature increased, the dominant species were Anabaena sp., Microcystis sp. and Oscillatoria sp., in that order. Anabaena sp. was dominant from spring to early summer with increase in water temperature and pollutant concentrations, and high correlation with environmental factors was observed. Microcystis sp. was dominant depending on changes in the nutrient levels. In the case of Oscillatoria sp., there was no significant correlation between phytoplankton biomess and Chl-a. However, efficient management of water environment and practical control of algal bloom in small scale reservoir polluted by livestock and farm irrigation should be achieved by identification of the relationship between algal growth and environmental factors.

• Journal of radiological science and technology
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• v.36 no.1
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• pp.1-10
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• 2013

IEC publications have applied in many countries all over the world such as Europe or Japan and these also have been published as in dustrial standards (KS) and notifications of Korea Food and Drug Administration (KFDA) in Korea. As the general standard of IEC 60601 series for medical electric (ME) equipment was revised as $3^{rd}$ edition in 2005, additional and particular standards have been revised or established newly. Under these circumstances, it is importance for manufacturing and assembling companies or authorized testing companies to understand the trend for revisions of IEC publications. Therefore in this study, the latest version of 3 IEC standards related to medical X-ray equipment : IEC 60601-2-44 for X-ray equipment for computed tomography (CT), IEC 60601-2-45 for mammographic X-ray equipment and IEC 60601-2-54 for X-ray equipment for radiography or radioscopy were covered and analyzed for trends and features accompanied by revision based on IEC 60601-1 $3^{rd}$ Ed. As KFDA notifications in force have referred to the particular standards based on 2nd edition of IEC 60601-1, those revised version of 3 particular standards were compared to KFDA notifications in force. The features of the latest standards applying IEC 60601-1 $3^{rd}$ Ed were shown as following: 1) Requirements for mechanical hazards, especially (motorized) moving parts were emphasized. 2) Indication and recording of patient dose were required. 3) Risk management process was introduced and enabled to monitor potential risks systematically. 4) DR system (digital radiography system) as well as analogue system (film-screen system) was included in the scope. Presently, KFDA will revise the notifications applying the particular standards based on IEC 60601-1 $3^{rd}$ Ed in a few years. Therefore the features of particular standards applying IEC 60601-1 $3^{rd}$ Ed was expected to help manufacturers, assemblers or testing companies of medical electric equipment understand IEC publications or KFDA notifications slated to be published.

• Journal of Korea Water Resources Association
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• v.51 no.1
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• pp.11-18
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• 2018

The climate change impacts on hydrological components and water balance in Jeju Island were evaluated using multiple climate models and watershed model, SWAT-K. To take into account the uncertainty of the future forecast data according to climate models, climate data of 9 GCMs were utilized as weather data of SWAT-K for future period (2010-2099). Using the modeling results of the past (1992-2013) and the future period, the hydrological changes of each year were analyzed and the precipitation, runoff, evapotranspiration and recharge were increasing. Compared with the past, the change in the runoff was the largest (up to 50% increase) and the evapotranspiration was relatively small (up to 11% increase). Monthly results show that the amount of evapotranspiration and the amount of recharge are greatly increased as the amount of precipitation increases in August and September, while the amount of evapotranspiration decreases in the same period. January and December showed the opposite tendency. As a result of analyzing future water balance changes, the ratio of runoff, evapotranspiration, and recharge to rainfall did not change much, but compared to the past, the runoff rate increased up to 4.3% in the RCP 8.5 scenario, while the evapotranspiration rate decreased by up to 3.5%. Based on the results of other researchers and this study, it is expected that rainfall and runoff will increase gradually in the future under the assumption of present climate change scenarios. Especially summer precipitation and runoff are expected to increase. As a result, the amount of groundwater recharge in Jeju Island will increase.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.268-277
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• 2014

This study assessed microbiological hazards at postharvest stage of dropwort farms (A, B, C, D, E, F, G, H, I) located in 4 different areas in Korea. The samples were assessed for sanitary indication bacteria (total aerobic bacteria, coliform, and Escherichia coli) and pathogenic bacteria (Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus and Bacillus cereus). Total aerobic bacteria and coliform in 9 dropwort farms were detected at the levels of 0~7.00 and 0~4.25 log CFU/g, mL, of $100cm^2$. In particular, microbial contamination in worker's hand showed higher than cultivation environment factors. Escherichia coli was detected in several farms of soil, irrigation water, washing water and worker's hand and also, dropwort in these farms was contaminated with E. coli (positive reaction). In case of pathogenic bacteria, B. cereus was detected at the highest levels in soil. S. aureus was detected qualitatively from only one sample of dropwort washed by water. E. coli O157:H7 and L. monocytogenes were not detected. Although dropwort pass through 2 process (trimming and washing), the microbial contamination was not differ significantly before and after which indicates that current washing system was not effect on reduction of microorganism. From these results, the postharvest environment and workers have been considered as cross-contamination factors. Thus, processing equipments and personal hygiene should be managed to reduce the microbial contamination of dropwort. Accordingly management system such as good agricultural practices (GAP) criteria is needed for the safety of dropwort