• The Korean Journal of Air & Space Law and Policy
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• v.6
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• pp.109-135
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• 1994

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2016.09a
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• pp.215-218
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• 2016

• The Korean Journal of Pesticide Science
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• v.15 no.1
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• pp.48-54
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• 2011

Risk assessments of pesticides detected in six major rivers during peak season were estimated for algae, Daphnia, and fish using hazard quotient (HQ) indexes. The eight pesticides (isoprothiolane, hexaconazole, diazinon, chlorpyrifos, prothiofos, alachlor, butachlor, molinate) were detected within the range of 0.027~12.871 ${\mu}g/L$. Detection frequency of isoprothiolate was estimated to be high at 67.5%, and those of the others varied from 15.0 to 37.5%, Hazard Quotients (HQ) indexes varied by freshwater organisms (algae, Daphnia, and fish). Overall, the ecological risk probability due to exposure of pesticides detected in major rivers did not reveal based on HQ indexes below 1.0. Particularly, butachlor and molinate for algae, chlorpyrifos, diazinon, prothiofos for Daphnia, and chlorpyrifos for fish acted as dominant contributors in increasing the ecological risk in six major rivers. This implied that integrated ecological risk assessment is required using various biological species, reflecting toxicity sensitivity. This study may provide the essential data in establishing the priority for pesticides management in major rivers, Korea.

• Journal of Microbiology and Biotechnology
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• v.26 no.7
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• pp.1290-1302
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• 2016

Microalgae are being researched for their potential as attractive biofuel feedstock, particularly for their lipid production. For maximizing biofuel production, it is necessary to explore the effects of environmental factors on algal lipid-producing potential. In this study, the effects of nitrogen (N) sources (NO₂-N, NO₃-N, urea-N, NH₄-N, and N-deficiency) and carbon-to-nitrogen ratios (C/N= 0, 1.0, 3.0, and 5.0) on algal lipid-producing potential of Chlorella sp. HQ were investigated. The results showed that for Chlorella growth and lipid accumulation potential, NO₂-N was the best amongst the nitrogen sources, and NO₃-N and urea-N also contributed to algal growth and lipid accumulation potential, but NH₄-N and N-deficiency instead caused inhibitory effects. Moreover, the results indicated that algal lipid-producing potential was related to C/N ratios. With NO₂-N treatment and carbon addition (C/N = 1.0, 3.0, and 5.0), total lipid yield was enhanced by 12.96-20.37%, but triacylglycerol (TAG) yields decreased by 25.52-94.31%. As for NO₃-N treatment, carbon addition led to a 17.82-57.43%/25.86-82.67% reduction of total lipid/TAG yields. When NH₄-N was used as the nitrogen source, total lipid/TAG yields were increased by 46.67-113.33%/28.99-74.76% with carbon addition. The total lipid/TAG yields of urea-N treatment varied with C/N ratios. Overall, the highest TAG yield (TAG yield: 38.75 ± 5.21 mg/l; TAG content: 44.16 ± 4.35%) was achieved under NO₂-N treatment without carbon addition (C/N = 0), the condition that had merit for biofuel production.

• PNF and Movement
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• v.17 no.3
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• pp.441-450
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• 2019

Purpose: This study identified the co-activation of quadriceps and hamstring muscles during hamstring strengthening exercises in healthy adults. Methods: Twenty-one participants were required for the present study design to achieve 80% power, 0.8 effect size (η2), and an alpha level of 0.05. Thus, this study recruited 21 healthy adults. All participants performed Nordic exercises, bridge exercises, and one-leg deadlifts randomly. The activity of the rectus femoris, vastus medialis (VM), vastus lateralis (VL), biceps femoris (BF), and semitendinosus (SM) were measured. In addition, the ratios of VM/VL and hamstring/quadriceps (HQ) were measured during the three hamstring strengthening exercises using electromyography. One-way ANOVA was used to compare the co-activation of quadriceps and hamstring muscles in the three exercises. Results: The activity of VM and VL during the performance of one-leg deadlifts was significantly higher than the other two exercises. The BF had significantly higher activity during the Nordic exercises compared to the other two exercises. In addition, the SM activation was significantly greater during Nordic exercises than one-leg deadlifts. Additionally, there was significant difference in HQ ratio among hamstring strengthening exercises. In specific, the one-leg deadlifts yielded a significantly lower HQ ratio. Conclusion: This study revealed that one-leg deadlifts are effective in rehabilitation for anterior cruciate ligament injury. In addition, Nordic exercises can be recommended to facilitate hamstring muscle activation.

• Korean Journal of Agricultural Science
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• v.51 no.1
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• pp.79-86
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• 2024

As the frequency and intensity of heavy rains increase, the vulnerability of agriculture to disasters also increases. Consequently, there is a need to improve flood and inundation predictions. To enhance the accuracy of inundation predictions, it is essential to monitor water level and discharge data within agricultural areas. This study was conducted to monitor water levels and rainfall in the Cheongju Sindae area from 2022 to 2023, and the data was utilized as input and validation data for agricultural inundation modeling. Four irrigation drainage canals were installed to a square-shaped concrete structure where the water level gauge is. It was then confirmed that the water level rises with rainfall. The flow velocities were monitored during periods of heavy rainfall. The rating curve, which estimates water level and flow velocity based on observations, was estimated using the software K-HQ. The resulting curve was presented with the Coefficient of Determination (R²). K-HQ was also used to calculate the equation for the rating curve, taking outliers into account at each data point. Outliers were extracted and the rating curve was recalculated. As the coefficient of determination of three out of four stations exceeded 0.95, the estimated rating curve may be considered reliable for discharge estimation. This study provides critical data for enhancing agricultural inundation modeling accuracy and drainage improvement projects.

• Journal of Life Science
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• v.17 no.9 s.89
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• pp.1284-1289
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• 2007

The Biological Activated Carbon (BAC) process in the water treatments represents a kind of biofiltration process which capabilities of bacteria to remove organic matters are maximized. It enables to eliminate organic matters and effectively reduce microbial regrowth potentials. As attached bacteria employ natural organic matter as a substrate, they are significantly dependent on indigenous microorganisms. In this study, characteristics of bacterial community by culturable and unculturable Methods have been conducted in a pilot plant using SAC in water treatment process at the downstream of the Nakdong River. Based on the results, HPC and bacterial- production for coal-based activated carbon material were $1.20{\sim}56.2{\times}l0^7$ cfu/g and $1.2{\sim}3.7\;mgC/m^{3}h$, respectively, in the SAC process. The highest level of attached bacteria biomass and organic carbon removal efficiency was found in the coal-based activated carbon. The genera Pseudomonas, Flavobacterium, Alcaligenes, Acilzetobacter, and Spingomonas were identified for each activated carbon material. Pseudomonas vesicularis was the dominant species in the coconut- and coal-based materials, where as Pseudomonas cepacia was the dominant species in the wood-based material. The Scanning Electron Microscope (SEM) observation of the activated carbon surface also found the widespread distribution of rod form and coccus. The community of attached bacteria was investigated by performing Fluorescent in situ hybridization (FISH) analysis. a group was dominant in coal, wood and coccunt-based materials, ${\alpha},\;{\beta}\;and\;{\gamma}$ group ranged from 27.0 ${\sim}$ 43.0%, 7.1 ${\sim}$ 22.0%, 11.3 ${\sim}$ 28.6%, respectively. These results suggest that a group bacterial community appears to be regulated removal efficiency of organic material in water treatment process.

• International Journal of Knowledge Content Development & Technology
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• v.7 no.1
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• pp.101-120
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• 2017

Healthcare professionals have edited many health questions (HQs) and their answers for healthcare consumers on the Internet. The HQs provide both readable and reliable health information, and hence retrieval of those HQs that are relevant to a given question is essential for health education and promotion through the Internet. However, retrieval of relevant HQs needs to be based on the recognition of the intention of each HQ, which is difficult to be done by predefining syntactic and semantic rules. We thus model the intention recognition problem as a text classification problem, and develop two techniques to improve a learning-based text classifier for the problem. The two techniques improve the classifier by location-based and area-based feature weightings, respectively. Experimental results show that, the two techniques can work together to significantly improve a Support Vector Machine classifier in both the recognition of HQ intentions and the retrieval of relevant HQs.

• Journal of Life Science
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• v.17 no.10
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• pp.1374-1380
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• 2007

The development of polymerase chain reaction (PCR) technology has the potential to solve for isolating pathogenic microorganisms from environmental samples than traditional plate counting methods. We have been detected pathogenic bacteria from raw water and water treatment process in Busan metropolitan city by PCR method. According to the result of survey from July 2004 to October 2005, 80 out of 92(87.0%) were positive for bacterial pathogens in raw water samples and positive rate of Shigella spp., Yersinia spp., Salmonella spp. and Legionella spp. were 46.2%, 40.7%, 17.6% and 9.9%, respectively. Pathogenic bacteria in raw water was mainly distributed through the lately Autumn to the winter and more highly detected Maeri than Mulgum region. During the period of survey in water treatment process, Shigella spp. was highly detected but all of bacterial pathogens were entirely removed after in post-ozonation step. These suggest that waters supplied in Busan metropolitan city may be safe against the pathogenic bacteria.

• Journal of Information Technology and Architecture
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• v.11 no.3
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• pp.311-320
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• 2014

The purpose of this research is to understand, through a case study, how the flexibility of Headquarter(HQ) and subsidiaries makes an effect on performance of global ERP system implementation in a global firm. The questions of this research are as follows. First, what types of flexibility are there for HQ and Subsidiary, respectively, which are related with global ERP system implementation? Second, how much impact do these types of flexibility have on the performance of global ERP system implementation? This research suggests three types of flexibility for HQ and three types of flexibility for subsidiaries that are related with the global ERP system implementation. In this study, BorgWarner, a global automobile parts manufacturer, was selected and analyzed to find out what kinds of flexibility contributed to enhancing its global ERP system implementation performance.