• Environmental Engineering Research
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• v.21 no.2
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• pp.196-202
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• 2016

Membrane bioreactor (MBR) technology has previously been used by water industry to treat high salinity wastewater. In this study, an anoxic-oxic biofilm-membrane bioreactor (AOB-MBR) system has been developed to treat mustard tuber wastewater of 10% salinity (calculated as NaCl). To figure out the effects of operating conditions of the AOB-MBR on membrane fouling rate ($K_V$), response surface methodology was used to evaluate the interaction effect of the three key operational parameters, namely time interval for pump (t), aeration intensity ($U_{Gr}$) and transmembrane pressure (TMP). The optimal condition for lowest membrane fouling rate ($K_V$) was obtained: time interval was 4.0 min, aeration intensity was $14.6 m^3/(m^2{\cdot}h)$ and transmembrane pressure was 19.0 kPa. And under this condition, the treatment efficiency with different influent loads, i.e. 1.0, 1.9 and $3.3kgCODm^{-3}d^{-1}$ was researched. When the reactor influent load was less than $1.9kgCODm^{-3}d^{-1}$, the effluent could meet the third discharge standard of "Integrated Wastewater Discharge Standard". This study suggests that the model fitted by response surface methodology can predict accurately membrane fouling rate within the specified design space. And it is feasible to apply the AOB-MBR in the pickled mustard tuber factory, achieving satisfying effluent quality.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.202-203
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• 2017

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2001.05b
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• pp.69-73
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• 2001

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.215-220
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• 2004

Satellite and aerial images are very useful means to monitor ecological and environmental situation. Nowadays more and more officials at Ministry of Environment in Korea need to access and use these image data through networks like internet or intranet. However it is very hard to manage and service these image data through internet or intranet, because of its size problem. In this paper very large image data service system for Ministry of Environment is constructed on web environment using image compression and web based image processing technology. Through this system, not only can officials in Ministry of Environment access and use all the image data but also can achieve several image processing effects on web environment. Moreover officials can retrieve attribute information from vector GIS data that are also integrated with the system.

• Korean Journal of Environmental Agriculture
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• v.37 no.1
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• pp.49-56
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• 2018

BACKGROUND: The mobile vortex wet scrubber was developed to remove the harmful chemicals from accidental releases. However, there was a disadvantage that it was limitedly used for volatile organic compounds (VOCs) such as toluene according to the physicochemical properties. This study compared the removal efficiencies of an improved mobile scrubber on toluene and ammonia by applying diverse adsorption and absorption methods. METHODS AND RESULTS: The removal efficiencies on harmful chemicals were examined using various adsorption and absorption methods of water vortex process (C), phosphoric acid-impregnated activated carbon adsorption (PCA), pH-controlled water (pH 2.5) vortex process absorption with sulfuric acid (SWA) after ammonia exposure, granular activated carbon adsorption (GCA), and activated carbon mat adsorption (CMA) after toluene exposure. As a result, the best removal efficiency was shown in the SWA for ammonia and GCA for toluene. Also, the SWA and GCA methods were compared with different concentration levels. In the case of ammonia exposure (5, 10 and 25%), there was no difference by concentration levels, and the concentration in the outlet gradually increased, with pH change from acid to base. In the case of toluene exposure (50, 75 and 100%), the outlet concentration was higher relative to the exposure concentration in the initial 10 min, but the outlet concentration was remained steady after 10 min. CONCLUSION: The newly improved mobile scrubber was also effective in removing VOCs through adsorption techniques (activated carbon, activated carbon fiber, carbon mat filter etc.), as well as removing acid-base harmful chemicals by neutralization reaction.

• Journal of Environmental Health Sciences
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• v.40 no.5
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• pp.331-345
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• 2014

Objectives: The exponential growth of chemicals, an area of high concern in developed countries like the US (i.e., the Gore Initiative) and in the EU (i.e., REACH), as well as recent chemical accidents in Korea, have provoked nationwide concerns and resultant legal enforcement. This study aims to compare the laws of the Ministry of Environment (the Chemical Substances Control Act (CSCA), Act on the Registration and Evaluation, etc. of Chemical Substances (ARECS)) with those of the Ministry of the Employment and Labor (Occupational Safety and Health Act (OSHA)). Methods: Each law pertaining to the Ministry of Environment and the Ministry of the Employment and Labor was downloaded from the official legal information system (www.law.go.kr). The objectives of each law and the major contents related to chemical management were compared and summarized. Results: The CSCA and the ARECS are focused on the protection of people and the environment, while the OSHA relates to the protection of workers. The right to know of people and workers has been reinforced. The former two laws emphasize prevention, but the OSHA contains both preventive and post-accident measures. The role of the Ministry of Employment was reinforced with the promulgation of the CSCA and ARECS, which contain regulations such as adjacent area impact evaluation, risk control planning, chemical statistical survey and construction and operation of information, provision of risk control plans, response to chemical accidents and registration of chemical substances. Conclusion: We found that the three laws discussed here have several similar clauses designed to protect people and the environment from risks that may be caused by the use of chemicals, even though there are some differences among them in terms of objectives and contents. This review concluded that several clauses that can be regarded as double regulation should be unified in order to minimize the waste of government administrative resources and socio-economic losses.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.2
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• pp.143-148
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• 2014

Arecoline is a major alkaloid of areca nuts which are widely chewed by southeast Asian and it manifests various toxic effects in different organs of human and animals. In this work, mature mice were treated by vitamins C plus E, arecoline, or both daily for four weeks. The results showed that arecoline significantly increased the levels of serum alkaline phosphatase (ALP), glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) and significantly decreased the levels of reduced glutathione (GSH), glutathione-S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT) in the liver tissues. Additionally, the body weight, testis weight, sperm counts, motility and normal sperms also were significantly decreased. The supplement of vitamins C and E can bring the activities of ALP and GPT to normal levels and partially restore the sperm counts compared to the arecoline-treated group but have no other positive effects. In conclusion, the vitamins C and E partially attenuated the arecoline-induced hepatotoxiciy but basically had on protective effects against the arecoline-induced testicular toxicity.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2732-2736
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• 2011

In pH 4.2 HAc-NaAc buffer solution, horseradish peroxidase (HRP) catalyzed $H_2O_2$ oxidation of nanosilver to form $Ag^+$. After centrifugation, $Ag^+$ in the supernatant can be measured by graphite furnace atomic absorption spectrophotometry (GFAAS) at the silver absorption wavelength of 328.1 nm. When HRP concentration increased, the $Ag^+$ concentration in the supernatant increased, and the absorption value enhanced. The HRP concentration in the range of 0.84-50 $ng{\cdot}mL^{-1}$ was linear to the enhanced absorption value (${\Delta}A$), with a regression equation of ${\Delta}A$=0.012C+0.11, correlation coefficient of 0.9988, and detection limit of 0.41 $ng{\cdot}mL^{-1}$ HRP. The proposed GFAAS method was used to detect HRP in waste water samples, with satisfactory results.

• Carbon letters
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• v.25
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• pp.50-54
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• 2018

Large-size graphene samples are successfully prepared by combining ultrosonic assisted liquid phase exfoliation process with oxidation-deoxidation method. Different from previous works, we used an ultrasound-treated expanded graphite as the raw material and prepared the graphene via a facile oxidation-reduction reaction. Results of X-ray diffraction and Raman spectroscopy confirm the crystal structure of the as-prepared graphene. Scanning electron microscopy images show that this kind of graphene has a large size (with a diameter over $100{\mu}m$), larger than the graphene from graphite powder and flake graphite prepared through single oxidation-deoxidation method. Transmission electron microscopy results also reveal the thin layers of the prepared graphene (number of layers ${\leq}3$). Furthermore, the importance of preprocessing the raw materials is also proven. Therefore, this method is an attractive way for preparing graphene with large size.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.7
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• pp.3475-3496
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• 2018

Most of current watermarking algorithms for GIS vector data embed copyright information by means of modifying the coordinate values, which will do harm to its quality and accuracy. To preserve the fidelity of vector line data and protect its copyright at the same time, a lossless watermarking algorithm is proposed based on storage feature in this paper. Firstly, the superiority of embedding watermark based on storage feature is demonstrated theoretically and technically. Then, the basic concepts and operations on storage feature have been defined including length and angle of the polyline feature. In the process of embedding watermark, the watermark information is embedded into directions of polyline feature by the quantitative mechanism, while the positions of embedding watermark are determined by the feature length. Hence, the watermark can be extracted by the same geometric features without original data or watermark. Finally, experiments have been conducted to show that coordinate values remain unchanged after embedding watermark. Moreover, experimental results are presented to illustrate the effectiveness of the method.