• Proceedings of the Korean Environmental Health Society Conference
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• 2002.04a
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• pp.26.1-28
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• 2002

Entrapped media with cellulous triacetate in which actived sludge was applied to induce operation factors and sewage treatment on site. The results are summarized as follows; The treatment efficiency of entrapped media is 92％, 90％ and 80％ at the size of 5mm, 7mm, and 12mm, respectively. Also, treatment efficient rate was increased by the packed amount of media in less than 30％ packed, while in more than 40％ packed that was decreased. It takes 10day to reach the steady states and it is less than the existing activated sludge method. The slopes of oxygen consumption rate are almost parallel both in the entrapped media and free sludge. When organic loading rate is less than 1.0 kg/㎥. d on site, it is achieved good removal rate independent of changes of loading rate.

• Agricultural and Biosystems Engineering
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• v.7 no.1
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• pp.18-26
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• 2006

In-field site-specific nitrogen (N) management increases crop yield, reduces N application to minimize the risk of nitrate contamination of ground water, and thus reduces farming cost. Real-time N sensing and fertilization is required for efficient N management. An 'on-the-go' site-specific N management system was developed and evaluated for the supplemental N application to com (Zea mays L.). This real-time N sensing and fertilization system monitored and assessed N fertilization needs using a vision-based spectral sensor and controlled the appropriate variable N rate according to N deficiency level estimated from spectral signature of crop canopies. Sensor inputs included ambient illumination, camera parameters, and image histogram of three spectral regions (red, green, and near-infrared). The real-time sensor-based supplemental N treatment improved crop N status and increased yield over most plots. The largest yield increase was achieved in plots with low initial N treatment combined with supplemental variable-rate application. Yield data for plots where N was applied the latest in the season resulted in a reduced impact on supplemental N. For plots with no supplemental N application, yield increased gradually with initial N treatment, but any N application more than 101 kg/ha had minimal impact on yield.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.152-154
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• 2004

A new model of selectively preferential sorption-facilitated transport with fixed site carriers was advanced in this paper. A number of experiments were arranged to demonstrate the ideal above. Preliminary results were obtained from the experiments, and shown the model was applicable for many membrane processes, such as RO, ED, gas separation and liquid membranes etc.

• Journal of Ecology and Environment
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• v.43 no.3
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• pp.289-296
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• 2019

We investigated the mortality and the oxidative damages of Deschampsia antarctica in response to waterlogging stress. In field, we compared the changes in the density of D. antarctica tuft at the two different sites over 3 years. The soil water content at site 2 was 6-fold higher than that of site 1, and the density of D. antarctica tuft decreased significantly by 55.4% at site 2 for 3 years, but there was no significant change at site 1. Experimental results in growth chamber showed that the $H_2O_2$ and malondialdehyde content increased under root-flooding treatment (hypoxic conditions-deficiency of $O_2$), but any significant change was not perceptible under the shoot-flooding treatment (anoxic condition-absence of $O_2$). However, total chlorophyll, soluble sugar, protein content, and phenolic compound decreased under the shoot-flooding treatment. In addition, the catalase activity increased significantly on the 1st day of flooding. These results indicate that hypoxic conditions may lead to the overproduction of reactive oxygen species, and anoxic conditions can deplete primary metabolites such as sugars and protein in the leaf tissues of D. antarctica. Under present warming trend in Antarctic Peninsula, D. antarctica tuft growing near the shoreline might more frequently experience flooding due to glacier melting and inundation of seawater, which can enhance the risk of this plant mortality.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.10a
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• pp.123-130
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• 1999

This paper presents a study of geotechnical treatment for artesian pressure after extensive investigation was performed on the distribution and characteristics of artesian condition which exists at Yangsan/Mulgeurn site. The result of analysis indicates that the artesian pressure seems to be up to 2.9M above the existing ground surface, originating from the higher ground water recharging sources in the surrounding hills and mountains. There is no harmful effect after the site development since the height of embankment is more than 4M above the existing ground surface.

• Journal of the Korean Professional Engineers Association
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• v.19 no.4
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• pp.11-21
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• 1986

Mine drainage from coal mines is mostly acidic, polluted and/or contaminated, even if its quantity has increased substantially during recent days. This causes two kinds of problems arising at mining districts; one is the environmental disruption and the other is insufficient water supply for living, employee's bathing and industrial purposes. In order to mitigate the aforementioned problems, a specific equipment of Korea type for mine drainage purification has been developed and its prototype manufactured, followed by its applicability tests implemented at mine site. The results of the tests indicates that the new equipment developed is much lower than and economical compared to, other existing neutralization facilities at home and abroad in capital investment at installation stage, the consumption of neutralizing chemicals at operation stage and the requirements of installation site. Whangji area where the prototype water treatment equipment is installed has been sustaining a short supply of usable water, especially in dry seasons and supplementing about 40㎥ of water brought from a location farther than 4km in distance to meet water requirements. The prototype water treatment equipment is however considered capable of providing compressor cooling water in sufficient amount from winter season In the future.

• Journal of Korean Society of Water and Wastewater
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• v.8 no.3
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• pp.26-33
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• 1994

To slove the problems by the scum, which causes operational and water quality problems in water treatment plants, several researches were conducted based on the site investigations on twelve large water treatment plants, biological and chemical analysis of scum, analyzing raw water quality data. Two types of scum, which are from scum and floe scum, can be classified based on the analysis and site investigations. The major parameter generating floe scum was indicated as fine bubbles dissolved in the water. The fine bubbles dissolved in the water can be generated by over-saturated air in the water, adding aluminum surface as the coagulant, conducting the break point pre-chlorination and so on. The water spray method, which is one of the physical treatment methods for removing scum, was selected for conducting experiments on the removal efficiency in the flocculation basin of the real water treatment plant. The water spray method was successfully applied for removing scum with the advantages of using spiral nozzles in case of using the raw water rather than the cleaned water.

• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.119-125
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• 2014

This study evaluated the environmental impacts of a soil washing (SW) process, especially, we compared the on-site and off-site remediation of TPH-contaminated soil using green and sustainable remediation (GSR) tool. To assess relative contribution of each stage on environmental footprints in the entire soil washing process, we classified the process into four major stages: site foundation (stage I), excavation (stage II), separation & washing (stage III), and wastewater treatment (stage IV). In on-site SW process, the relative contribution of $CO_2$ emissions and energy consumption were 87.1% and 80.4%, respectively in stage I, and in off-site SW process, the relative contribution of $CO_2$ emissions and energy consumption were 82.7% and 80.5%, respectively in stage II. In conclusion, the major factor contributing environmental impact in the SW process were consumable materials including steel and stainless steel for washing equipment in on-site treatment and fuel consumption for transportation of soil in off-site treatment.

• Journal of Life Science
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• v.8 no.3
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• pp.339-347
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• 1998

As a part of a study on the development of microbiological methods for petroleum exploration, the distribution of the avarafe survival rate for heterotrophs to various heavy metal ions and hydrocarbons were surveyed and compared by the use of plate count method. In consequence of the avarage survival rate to heavy metal ions(2 hours treatment) and hydrocarbons(1 hour treatment) for heterotrophs isolatinf from soil samples(50cm depth) which located in Doum mountain(A, B and D site) and Aedowon(C site) at Pohang area, the survival rate of heterotrophs for nickel(600ppm), cobalt(500ppm), cadmiun(100ppm), mercury(20ppm), zinc(400 ppm) and lead(500ppm) were 73.7%, 82.6%, 76.8%, 9.5%, 77.8% and 73.6% at A site and 67.9%, 82.5%, 86.0%, 5.8%, 82.5% and 91.7% at B site, 87.8%, 79.8%, 87.5%, 7.0%, 84.2% AND 47.7% AT c SITE, AND 71.8%, 76%, 85.9%, 1,2%, 79.6% AND 88.3% AT D site, respectively. Also the survival rate of heterotrophs from A,B,C and D site to pentane and hexane(each concentration is 20%) were 26.7% and 42.5%, 11.8% and 8.1%, 44.3% and 36.2%, and 12% and 3.5%, respectively. therefore, heterotrophs from B and D site that alternated gravelstone, muddy sandstone and sandstone were higher survival rate to the heavy metal ions than heterotrophs from A site which mainly composed gravelstone. Also, heterotrophs from C site which mainly composed muddy sandstone and once produced natural gas were showed relatively higher survival rate to the heavy metal ions and hydrocarbons than the other sites. Consequently, we confirmed that the distributions of tolerant heterotrophs to heavy metal ions and hydrocarbons were differ from the lithological compositon.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.3
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• pp.138-146
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• 2007

Objective : To observe the trend in clinical study on atopic dermatitis(AD) over the last 3 years in order to develop a study methodology of AD in Oriental Medicine. Methods : Using the Pub med on line site; search terms: atopic dermatitis, field as title/abstract, limitation as published in the last 3 years, only items with links to full text, Humans, Clinical Trial, English. I observed the study contents of all this research and focused on the classification of treatments. I also observed of AD clinical trials registered on a clinical trial site(www.clinicaltrial.gov) on 23rd of June, 2007: study contents, localization and study designs. Results : Through the Pub Med site, I found 169 articles. Classified according to study subject, the studies related to treatment were 114(67.5%); physiology, pathology and prevention 12(7.1%); Diagnosis and Evaluation(7.1%); psychological aspects including quality of life 10(5.9%); diet and management 10(5.9%); epidemiology 7(4.1%); and others 7(4.1%). However, the treatment study of herb-medicine as intervention showed only 1 article. Futhermore, it wasn't based on Oriental Medicine philosophy. In the clinical trial site, there were 31 studies in which patients were recruited or planned for the future. The study on efficacy and safety of the medicine produced 14 trials, 5 comparative trials, 2 phototherapy, 2 diagnosis, 6 physiology and pathology, and 2 epidemiology. The trial institutions were concentrated in U.S.A. Conclusion : I suggest we'd better try to make a good clinical guideline and standardization of diagnosis and herb-medicine in order to develop a clinical study methodology of AD as soon as possible in the future. Even though it 's very hard to find the study methodology, we should aim to achieve positive results and show the evidence of the efficacy and safety of herb-medicine treatment for AD using Oriental Medicine.