• Korean Journal of Microbiology
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• v.49 no.4
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• pp.343-352
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• 2013

In this study, we have evaluated the effect of efficient microorganisms on odor-removal efficiency and early stabilization of the burial sites. We have developed an efficient microorganism designated as 'KEM' which have the ability to degrade organic compounds and remove odor effectively. Other efficient microorganisms already used on site, such as EM and Bacillus sp., were also compared. We preceded these experiment using lab-scale reactors under three conditions (control, only media and only body) and comparing the effect of with or without the application of tree efficient microorganisms separately. Analysis was focused on eight components (ammonia, TMA, $H_2S$, methyl mercaptan, dimethyl sulfide, dimethyl disulfide, $CO_2$ and $CH_4$), and as a result, efficient microorganisms were shown efficiency in the removal of ammonia and methyl mercaptan. The applied KEM decayed up to 71.2% of the buried meat. We were unable to observe significant differences in microbial communities between efficient microorganisms-treated and non-treated reactors due to the large presence of microorganisms in both soil and carcasses. However, it was possible to observe the effect on odor control and decay rate through the application of efficient microorganisms.

• Journal of the Korean Society of Radiology
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• v.10 no.6
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• pp.419-425
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• 2016

The purpose of this study is to produce a shielding material to reduce a dose on the genital gland, one of the superficial organs, at a CT scan on the whole abdomen and hardly affect picture quality and examine its utility. This research made 22 mm silicone and 7.3 mm aluminum having the similar material quality and effect of previous bismuth. By using the non-shield, bismuth, 22 mm silicone, and 7.3 mm aluminum shielding materials, this author conducted a comparative experiment measuring the decay rate of the genital gland's exposure to radiation, change of the CT number and noise in the image, and the CT number, noise, and uniformity in the AAPM phantom. According to the results, exposure to radiation is reduced in bismuth as 29.96%, silicone 22 mm as 13.10%, and 7.3 mm aluminum as 18.27%. In bismuth, however, the image's CT number varies a lot, and uniformity is measured to be inappropriate in the AAPM phantom scan; therefore, it indicates great change in terms of picture quality in superficial organs like the genital gland. Concerning superficial organs like the genital gland, if 22 mm silicone and 7.3 mm aluminum are used as shielding materials, it will be helpful in reducing variation in picture quality and also decreasing radiation exposure to radiation.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.3
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• pp.112-117
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• 2000

Food waste is the main source of decay, odors and leachate in collection, transportation and landfill due to the high volatile solids (VS) and moisture content. Acidogenic fermentation of food waste is affected by the fermentation constraints including the biodegradability of substrate and the degrading capability of microorganisms. The biodegradability of food waste is mainly related to cellulosic materials, which are hardly degraded and comprise about 50% of food waste. The efficient and economical method of improving hydrolysis is, therefore, to apply microorganisms with increased cellulose-degrading capability. In this experiment, rumen microorganisms were inoculated to improve the low efficiency of acidogenic fermentation, and then compared with that of mesophilic acidogens. The fermentation of food waste in a leaching bed reactor employing rumen microorganisms resulted in the enhanced acidification (71.2% at $3.0d^{-1}$), which was higher than that (59.8% at $4.5d^{-1}$) employing mesophilic acidogens. This indicated that Rumen microorganisms had an enhanced waste-degrading capability.

• Applied Biological Chemistry
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• v.10
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• pp.63-68
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• 1968

The effects of $^{60}Co-{\gamma}$ radiation on the change of composition and susceptibility to soft rot during the storage of sweetpototoes and the radioresistance of spores of the soft rot fungus were investigated and the following results were obtained. 1) Gamma-irradiation of sweetpotatoes caused the increase in water-soluble sugar content and the decrease in ascorbic acid content during the storage. 2) The rate of oxygen uptake in sweetpotato slices becomes higher as the dose increases. But the oxygen uptake in slices irradiated with higher doses decreases along with the color change as the time passes. 3) Irradiation with high doses (above $2.5{\times}10^5$ rad) brought about the increased susceptibility to soft rot decay as the chilling injury did in the storage of sweetpotatoes. 4) Average lethal dose for the spores of Rhizopus nigricans was $3.0{\times}10^5$ rad and the complete death required the level of $1.25{\times}10^6$ rad.

• Journal of the Korean Electrochemical Society
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• v.3 no.1
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• pp.5-10
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• 2000

In the present work, corrosion rate W and corrosion potential tow were simultaneously measured as a function of relative humidity RH employing the electrochemical wet and dry method as an accelelated atmospheric corrosion method. The W versus (vs.) RH curve is classified into .three regions, namely, the first W plateau region, the second region of the linear relationship between logarithmic W and RH, finally, followed by an abrupt decay region. Based upon the atmospheric corrosion mechanism of mild steel, we introduced another diagram of $\varepsilon_{corr}$ vs. RH which is divided into three regions. In the first region, the corrosion scales are composed of single lepidocrocite-phase $(\gamma-FeOOH)$; in the second region, $\gamma-FeOOH$-phase coexists with magnetite-phase $(Fe_3O_4)$ in the scales and finally the oxide scales change into a single Fe304-phase in the third region. The three distinct regions of both representations share almost each other, which is validated by FT-IR (Fourier transform infra-red) analysis and surface observation. Both representations prove to be convenient and complementary for surveying the spectrum of the atmospheric corrosion of mild steel.

• Horticultural Science & Technology
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• v.34 no.4
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• pp.644-654
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• 2016

Supervised residue trials for mandipropamid in Korean cabbage(Brassica campestris L.) were conducted to establish its pre-harvest residue limit (PHRL), a criterion to ensure the safety of the terminal pesticide residue during cabbage production. Tissues of Korean cabbage were collected at 0, 1, 3, 5, 7, and 10 days after mandipropamid application and subjected to residue analysis. The analytical method was validated by recoveries ranging from 88.2-92.2% at two levels (0.4 and $2.0mg{\cdot}kg^{-1}$), and a limit of quantitation (LOQ) of $0.04mg{\cdot}kg^{-1}$. Mandipropamid residues in Korean cabbage gradually decreased over time. The dissipation rate of the residue would be affected by intrinsic degradation of the compound along with dilution resulting from the fast growth of Korean cabbage. The decay pattern was well fitted by simple first-order kinetics. Biological half-lives of mandipropamid in Korean cabbage ranged from 3.9-4.0 days in two field conditions. Calculated by the regression curve of mandipropamid dissipation, the PHRLs of mandipropamid in Korean cabbage were recommended as 11.07-12.19 and $5.76-6.05mg{\cdot}kg^{-1}$ for 10 and 5 days prior to harvest, respectively.

• Horticultural Science & Technology
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• v.31 no.3
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• pp.289-298
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• 2013

Effects of curing treatments and storage temperature on the quality of Chinese yams (Dioscorea polystachya Turcz.) were investigated stepwise in three consecutive years for the optimization of postharvest handling procedures. Tuberous roots were harvested in early to mid November and cured under ambient or $29^{\circ}C$ heated air conditions for various periods according to the treatment conditions. Storage temperatures in the range of 0.5 to $7.5^{\circ}C$ were phased in to avoid chilling injury while examining storage potential from 4 to 7 months. As poststorage technology, short-term $60^{\circ}C$ hot-air exposure or low shelf temperature treatments were additively imposed. Curing treatments, especially heated air curing for 3-5 days tended to reduce the respiration and weight loss during storage while maintaining flesh firmness. Storage at $0.5^{\circ}C$ brought out typical chilling injury symptoms on the shelf with increases in respiration and lower flesh firmness by tissue breakdown resulting in the rapid loss of marketability. Optimum storage temperature appeared to be the $3-4^{\circ}C$ range which suppresses quality deterioration while avoiding chilling injury. Low shelf temperature seemed to be a necessary part of postharvest handling system to keep marketability through control of poststorage disorders such as rooting and decay. Overall results suggested that optimized postharvest program consisting of heated-air curing, storage at $3-4^{\circ}C$, and low shelf temperature could extend storage potential of Chinese yam to longer than 7 months.

• Korean Journal of Microbiology
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• v.47 no.1
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• pp.22-29
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• 2011

Rhodopsin is a membrane protein with seven transmembrane region which contains a retinal as its chromophore. Although there have been recently reports on various photo-biochemical features of rhodopsins by a wide range of purifying and measurement methods, there was no actual comparison related to the difference of biochemical characteristics according to their physical environment of rhodopsins. First, proteorhodopsin (PR) was found in marine proteobacteria whose function is known for pumping proton using light energy. Second one is Anabaena sensory rhodopsin (Nostoc sp.) PCC7120 (ASR) which belongs to eubacteria acts as sensory regulator since it is co-expressed with transducer 14 kDa in an operon. In this study, we applied two types of rhodopsins (PR and ASR) to various environmental conditions such as in Escherichia coli membranes, membrane in acrylamide gel, in DDM (n-dodecyl-${\beta}$-D-maltopyranoside), OG (octyl-${\beta}$-D-glucopyranoside), and reconstituted with DOPC (1,2-didecanoyl-sn-glycero-3-phosphocholine). According to the light-induced difference spectroscopy, rhodopsins in 0.02% DDM clearly showed photointermediates like M, and O states which respond to the different wavelengths, respectively and showed the best signal/noise ratio. The laser-induced difference spectra showed the fast formation and decay rate of photointermediates in the DDM solubilized samples than gel encapsulated rhodopsin. Each of rhodopsins seemed to be adapted to its surrounding environment.

• The Korean Journal of Mycology
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• v.30 no.2
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• pp.78-85
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• 2002

Fifteen isolates from pear, and sixteen isolates from KCTC, KCCM, and Chungnam Univ. of Penicillium spp. were investigated for the analysis of their relationships of cultural characteristics and RAPD genetic variation by RAPD. The cultural characteristics of Penicillium spp. were shown different growth rate, morphology, and color. In addition, the cultural characteristics and RAPD analysis were conducted for the pear rot pathogens and related isolates. RAPD patterns were applied to compare the taxonomic and genetic diversity of the Penicillium species between 15 groups isolated from pear fruits and 16 standard species. The genomic DNA were amplified from $0.1{\sim}2.0kb$ by five URP primer and 744 bands were detected. The cluster analysis showed four genomic DNA RAPD groups and its similarity was 47.7%. Intraspecific relationships were 87.4, 97.5 and 95.2%, in P. expansum, P. solitum, and P. crustosum, respectively. These results appeared to be that there were high similarities between isolates, and consistent with the results of cultural morphological characteristics analysis.

• The KIPS Transactions:PartD
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• v.11D no.1
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• pp.83-94
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• 2004

Recent researches which purport to Integrate distributed information have been concentrated on developing efficient mediator systems that not only provide a high degree of autonomy for local users but also support the flexible integration of required functions for global users. However, there has been little attention on how to evaluate a global query in a mediator. A global query is transformed into a set of its sub-queries and each sub-query is the unit of evaluation in a remote server. Therefore, it is possible to speed up the execution of a global query if the previous results of frequently evaluated sub-queries are materialized in a mediator. Since the Integration schema of a mediator can be incrementally modified and the evaluation frequency of a global query can also be continuously varied, query usage should be carefully monitored to determine the optimized set of materialized sub-queries. Furthermore, as the number of sub-queries increases, the optimization process itself may take too long, so that the optimized set Identified by a long optimization process nay become obsolete due to the recent change of query usage. This paper proposes the adaptive selection of materialized sub-queries such that available storage in a mediator can be highly utilized at any time. In order to differentiate the recent usage of a query from the past, the accumulated usage frequency of a query decays as time goes by.