• Journal of Soil and Groundwater Environment
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• v.19 no.3
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• pp.56-65
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• 2014

Contamination of explosive compounds in the soils of military shooting range may pose risks to human and ecosystems. As shooting ranges are located at remote places, active remediation processes with hardwares and equipments are less practical to implement than natural solutions such as bioremediaton. In this study, a series of experiments was conducted to select a suitable carbon source and to optimize dosing rate for the enhanced bioremediation of explosive compounds in surface soils and sediments of shooting ranges with indigenous microorganisms activated by external carbon source. Treatability study using slurry phase reactors showed that the presence of indigenous microbial community capable of explosive compounds degradation in the shooting range soils, and starch was a more effective carbon source than glucose and acetic acid in the removal of TNT. However, at higher starch/soil ratio, i.e., 2.0, the acute toxicity of the liquid phase increased possibly due to transformation products of TNT. RDX degradation by indigenous microorganisms was also stimulated by the addition of starch but the acute toxicity of the liquid phase decreased with the increase of starch/soil ratio. Taken together, the optimum range of starch/soil ratio for the degradation of explosive compounds without significant increase in acute toxicity was found to be 0.2 of starch/soil.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.5
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• pp.2651-2673
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• 2019

In order to detect Denial of Service (DoS) attacks, victim-side detection methods are used popularly such as static threshold-based method and machine learning-based method. However, as DoS attacking methods become more sophisticated, these methods reveal some natural disadvantages such as the late detection and the difficulty of tracing back attackers. Recently, in order to mitigate these drawbacks, source-side DoS detection methods have been researched. But, the source-side DoS detection methods have limitations if the volume of attack traffic is relatively very small and it is blended into legitimate traffic. Especially, with the subtle attack traffic, DoS detection methods may suffer from high false positive, considering legitimate traffic as attack traffic. In this paper, we propose an effective source-side DoS detection method with traffic seasonality aware adaptive threshold. The threshold of detecting DoS attack is adjusted adaptively to the fluctuated legitimate traffic in order to detect subtle attack traffic. Moreover, by understanding the seasonality of legitimate traffic, the threshold can be updated more carefully even though subtle attack happens and it helps to achieve low false positive. The extensive evaluation with the real traffic logs presents that the proposed method achieves very high detection rate over 90% with low false positive rate down to 5%.

• Journal of Biosystems Engineering
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• v.3 no.1
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• pp.64-76
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• 1978

A dimensional supply of petroleum fuels and increased competition for petroleum products has made the conservation of energy in grain drying an important cost and management factor. Research on solar grain drying is directed toward utilization of a renewable energy source as an alternative to petroleum fuels for drying. There are many technical and economic problems in accepting and adopting solor energy as a new energy source for grain drying. The purpose of this study are to assess the state of the art of solar grain drying and to find out the problems by reviewing literatures available. The results obtained may be summarized as follows; 1.It may be considered that the weather conditions in October of Korea was satisfactory for the forced natural air and solar heated air drying. 2. Solar energy is considered more applicable to low-temperature, In-storage drying systems than to high-temperature, high-speed drying systems. In-storage drying systems require low levels of heat input. The costs of collector systems to provide low temperature are considerably cheaper than for high-temperature systems. 3. Tubular type collector made of polyvinyle film seems to be the most practical at this stage of development and black-painted bare-plate collectors mounted on the outside of a typical, round, low-temperature drying bin can supply an appreciable amount of the energy efficiently needed for low-temperature grain drying at a lower cost. 4. All of the grains in solar drying tests was successfully dried up to safe storaged moisture levels without significant spoilage. Drying rates with solar system were faster than natural air drying systems, and usually a little slower than similar low-temperature electric drying systems. 5. Final grain moisture levels were lower in solar tests than in natural air tests, and generally higher than in tests with continuous heated air. 6. Savings of energy by use of solar collectors ranged from 23% to 55%, compared to the natural and electric ileated air drying systems. However, total drying cost effectiteness tvas not significant. Therefore, it is desirable that solar grain dry-ing sIFstems tvhich could be suitable for multiple heating purposes on farms shouldbe developed. 7. Supplemental heat with solar radiation did little to reduce air flow requirementsbut refuced drying time and increased the p\ulcornerobability of successful drying duringdrying poriod.

• Journal of Korean Society on Water Environment
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• v.25 no.5
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• pp.713-719
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• 2009

A natural wetland in the Nakdong River basin which effectively removes non-point source pollutants was investigated for 2 years to understand wetland topography, vegetation types, and water quality characteristics. The water depth of the natural wetland was in the range of 0.5~1.9 m which is suitable for the growth of non-emergent hydrophytes. The wetland has a high length to width ratio (3.3:1) and a relatively large wetland to watershed area ratio (0.057). A broad-crested weir at the outlet increases the retention time of the wetland whose hydrology is mainly dependent on storm events. The concentrations of dissolved oxygen in the growing season and the winter season showed anoxic and oxic conditions, respectively. Diurnal variations of DO and pH in the growing season were also observed due to weather change and submerged plants. COD and TP concentrations were low in the winter season due to low inflow rate and increased retention time. Increased TP concentrations in the spring season were caused by degradation of dead wetland plants. Nitrogen in the wetland was mostly in organic nitrogen form (>75%). During the growing season, ammonium concentration was high but nitrate nitrogen concentration was low, possibly due to anoxic and low pH conditions which are adverse conditions for ammonificaiton and nitrification. The results of this study can be used as preliminary data for design, operation, monitoring and management of a constructed wetland which is designed to treat diffuse pollutants in the Nakdong river watershed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.154-159
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• 2018

Intentional releases occur frequently during maintenance in gas supplying companies, which may result in unpleasant odors, and the possible mistaken belief of a gas accident. Therefore, this study developed a chemical process for effective odorant removal in natural gas using an active chemical that is released intentionally during maintenance and inspection. To develop an effective treatment process for removing the odorant from released natural gas, the effluent concentrations of the odorant in the released gas were measured after a chemical oxidation reaction with a sodium hypochlorite solution in a compact gas scrubbing equipment newly devised in this study. The device was based on a mixed gas vent after the solution inject odorant in the gas through the energy of the venting gas. The cascade combination of a venturi pipe and mixing chamber was developed to remove the odorant effectively from the purposely-released natural gas using an oxidative reaction between the mercaptan compounds (odorant) and the sodium hypochlorite solution. On the other hand, the developed method could be applied limitedly to a relatively small gas release from a low-pressure source. Further studies will be needed to apply the developed process to a large-scale gas release from a high-pressure source.

• The Journal of the Petrological Society of Korea
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• v.23 no.4
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• pp.367-373
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• 2014

Yeongsan-eupseong is located at Seongnae-ri, Yeongsan-myeon, Changnyeong-gun, Korea. We investigated the petrological features of the stone materials used for the rampart, and estimated their provenances. The stone materials consist of andesitic rocks, granitic rocks and sedimentary rocks. In the preserved rampart the andesitic rocks are relatively abundant, whereas the large number of granitic rocks are used for restoration. Chaeyaksan andesite and Chusan andesite are thought to be the source for the andesitic rocks. The original granitic rocks are of granite porphyry, and are likely to have been delivered from the near granite porphyry outcrops. On the other hand the granitic rocks used for restoration are classified to be biotite granite. The sedimentary rocks show thermally metamorphosed feature and changed to hornfels. The source for the hornfels is the contact area between the sedimentary rocks and granitic rocks near the Yeongsan-eupseong.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.12
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• pp.1933-1941
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• 2019

Objective: This study was conducted to evaluate quality characteristics of cured pork loin with natural nitrite source from Swiss chard. Methods: Pork loin was cured in brine and the ratio of water and fermented Swiss chard (FSC) solution in the brine was changed by 4:0 (control), 3:1 (T1), 1:1 (T2), 1:3 (T3), 0:4 (T4), and pickled samples with 0.012% sodium nitrite (PC, positive control) and nitrite free brine (NC, negative control) were considered as the control. Results: The pH values of cured pork loins with FSC were decreased with increasing addition level of FSC. Cooking loss was not significantly different among all treatments. T4 had the lowest value in moisture content and lightness value and the highest value in curing efficiency. The redness value of T4 was not significantly different from that of PC in raw. After cooking, however, it was higher than that of PC. The yellowness value of cured pork loin added with FSC was increased with increasing level of FSC. Volatile basic nitrogen content of cured pork loin added with FSC was higher than PC and NC. Thiobarbituric acid reactive substance value of cured pork loin added with FSC was decreased with increasing FSC level. Residual nitrite level and shear force were increased with increasing FSC level. In the sensory evaluation, sensory score for flavor, off-flavor, chewiness, juiciness, and overall acceptability were not significantly different among all treatments. However, sensory score for color was increased when the concentration of FSC added to pork loin was increased. Conclusion: The FSC solution had a positive effect on redness and lipid oxidation. As shown by the results in protein deterioration and sensory, Swiss chard can replace sodium nitrite as natural curing agent.

• Journal of Digital Convergence
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• v.19 no.12
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• pp.513-521
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• 2021

The purpose of this study is to suggest an anti-aging health care plan through a literature analysis of the life activity system of Oriental Medicine. The source of normal maintenace, development, and change of the natural world and the human body's life activity process is the dynamical cooperative equilibrium of the internal Shen-Ji's discipline that creates, grows, changes, makes differences and stores(生长化收藏) and external Qi-Li's process of change from birth to growth, maturity to old age and ending of life(生長壯老已). Therefore, it was analyzed that the natural and human life activity processes are normally maintained, developed, and transformed. As a result, when the natural healing power of Genuine-Qi, the source of the human vitality, rises with the 'breathing massage' that combines a static breathing method which is anti-aging health care method applying the lifting entering movement of Qi and a dynamic abdominal massage, and it harmonizes the Shen-Ji which is the life process system and Qi-Li so that it is believed to be helpful in prolonging a healthy lifespan.

• Korean Journal of Plant Tissue Culture
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• v.25 no.6
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• pp.477-485
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• 1998

To underatand in vitro regulation of differentiation, the effects of growth regulators and nitrogen source on metabolism of cell wall polysaccharides in suspension culture of kidney bean (Phaseolus vulgaris L.) were investigated. The suspension cells (cell clusters) were directly induced from the epicotyl segments of the seedlings, which were cultivated in MS medium supplemented with 1.0mg/L of 2,4-D and 0.5 mg/L of kinetin. When compared with cell wall sugar contents of the epicotyl segments, the cellulose content of the suspension-cultured cells decreased; while the pectin and hemicellulose content increased; suggesting increases of rhamnogalacturonan I and arabinogalactan IIduring the dedifferentiation, respectively, The effects of growth regulators(2,4-D, 1.0mg/L and kinetin, 0.5mg/L) and nitrogen source (potasium nitrate, 19.0mg/L and ammonium nitrate, 16.5 g/L) in the medium on the proliferation and the turnover of the cell wall polysaccharides were investigated for 30 days. In the medium with growth regulators and without nitrogen source, the proliferation rate was extremely high (16 folds). Growth regulators and nitrogen source increased the pectin content. Analysis of neutral sugar composition of pectin fraction showed that nitrogen source enhanced rhamnose level remarkably, suggesting that rhamnogalacturonan I was the one most likely synthesized. In hemicellulose fraction, growth regulators reduced arabinose level, suggesting that arabinogalactan II was degraded. And nitrogen source reduced galactose level, suggesting that xyloglucan was also degraded.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.651-660
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• 2006

Natural products are a rich source of biologically active small molecules and a fertile area for lead discovery of new drugs [10, 52]. For instance, 5% of the 1,031 new chemical entities approved as drugs by the US Food and Drug Administration (FDA) were natural products between 1981 and 2002, and another 23% were natural product-derived molecules [53]. These molecules have evolved through millions of years of natural selection to interact with biomolecules in the cells or organisms and offer unrivaled chemical and structural diversity [14, 37]. Nonetheless, a large percentage of nature remains unexplored, in particular, in the marine and microbial environments. Therefore, natural products are still major valuable sources of innovative therapeutic agents for human diseases. However, even when a natural product is found to exhibit biological activity, the cellular target and mode of action of the compound are mostly mysterious. This is also true of many natural products that are currently under clinical trials or have already been approved as clinical drugs [11]. The lack of information on a definitive cellular target for a biologically active natural product prevents the rational design and development of more potent therapeutics. Therefore, there is a great need for new techniques to expedite the rapid identification and validation of cellular targets for biologically active natural products. Chemical genomics is a new integrated research engine toward functional studies of genome and drug discovery [40, 69]. The identification and validation of cellular receptors of biologically active small molecules is one of the key goals of the discipline. This eventually facilitates subsequent rational drug design, and provides valuable information on the receptors in cellular processes. Indeed, several biologically crucial proteins have already been identified as targets for natural products using chemical genomics approach (Table 1). Herein, the representative case studies of chemical genomics using natural products derived from microbes, marine sources, and plants will be introduced.