• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.1
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• pp.54-63
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• 2010

Recently, as the function of largest supplier of biomass for "low carbon green growth", the necessity for systematic management of afforestation areas is emphasizing. The forestation of seedling, besides the afforestation cost itself, is required some additional follow-up management costs, like mowing and fertilizing of forestation area, and removal of bindweed. The mulching mat for afforestation seedlings is available for rooting of little seedlings as well as initial forestation expenses. Mulching technique is also used to control soil temperature and moisture by covering the surface of ground. In this study, the paper based-mulching film coated with biodegradable polymer and functional additive was specially produced using laboratory bar coater, and analyzed for its degradable behavior. Coating colors were prepared by dissolving PE (polyester) 80 % and PLA(polylactic acid) 20 % in chloroform and finally applied to handsheet prepared by preceding study conditions. Base paper and polymer-coated paper were artificially aged by 2 kinds of degradation methods, which are soil degradation by microorganism and light degradation by 257 nm UV wavelengths. Strength property, oxidation index and morphological property were evaluated by reduction rates of tensile strength, FTIR spectra ratio of carboxyl and carbonyl group and SEM micrograph. As these results, polymer coated-paper was superior to base paper in degradation behaviors, having results with lower reduction rate of strength properties.

• Journal of Korea Technology Innovation Society
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• v.17 no.2
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• pp.334-354
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• 2014

This study aims to analyze the research trend of Korean medicine based on social network analysis. To do this, a dataset has been collected from KCI (Korea Citation Index) database. According to the results, we have identify the longitudinal trend of the number of papers, journals, organizations and key words in this field. Moreover, based on the nodes' centrality of co-author network, we have found a core journal (i.e. Korean Journal of Oriental Physiology and Pathology), a hub institution (i.e. Kyunghee university) and two main key words (i.e. anti-oxidation and acupuncture) in the research network. In conclusion, integrating field experts' tacit knowledge in Korean medicine studies with the results of the explicit social network analysis on the research trend, we put forward further policy implications with regard to R&D strategies in this field.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1289-1294
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• 1999

To identify the effect of packaging film on browning reaction of dried squid, 3 kinds of packaging film$(NYLON\;12\;{\mu}m/LDPE\;80\;{\mu}m)$ including transparency, white, black film were tested about browning degree of dried squid during storage at ambient temperature for 50 days. During storage period, water content and water activity were maintained almost constant, and microbial count was not changed. When color index was measured by color difference meter, L value and ${\Delta}E$ value were the highest in the dried squid packaged with transparency film. ${\Delta}E$ value was rapidly increased in early packaging period(within 10 day). TBA value was showed same tendency with ${\Delta}E$ value in early storage period. So, the browning was supposed to originated from lipid oxidation by UV light transmitted through packaging film in the early storage period.

• Journal of Environmental Science International
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• v.19 no.11
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• pp.1355-1362
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• 2010

This study was carried out in order to observe how the bay sediment would be changed with microbial treatments and a chemical oxidant like $CaO_2$. The sediment during the treatments was analyzed in terms of pH, ORP, volatile organics content, COD, AVS, T-N, and T-P. With $CaO_2$ treatment, pH was kept over 9.66 and ORP ranged from +4.70~+46.0, which meant an aerobic state meanwhile with the microbial treatment those were worse. In addition the chemical treatment showed better environmental index values than the microbial one: volatile organics content and COD values in the former were 12.9% and 37.9% while those in the latter were 4.5% and 18.7%, respectively. AVS and T-P were 71.1% and 100% versus 56.5% and 85.8%, respectively. However, the microbial treatment was better for T-N(66% higher). On the other hand, both treatment at a time enhanced all the environmental indices but COD meantime pH and ORP values were lower than with the chemical treatment only. Thus additional input of an oxygen generator like $CaO_2$ could improve the environmental state of a bay sediment where the biological treatment is going on.

• Journal of Acupuncture Research
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• v.23 no.6
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• pp.19-27
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• 2006

Objectives : Type analysis is done on pharmacopuncture related papers published in the Journal of Korean Acupuncture and Moxibustion from the inaugural issue to August 2006 issue. Methods : Journal search engine KSI ISS and KSI KISS were mainly used and additional sources were complemented by the index issue and English journals. Results : 1. The number of journals associated with pharmacopuncture is 438 papers. 2. For type analysis of the type of studies, experiment papers outnumbered other types with 355 cases, followed by 70 for clinical trials, and 14 for literary studies. 3. For type analysis of the pharmacopuncture extracts, bee venom related papers were most numerous with 101 cases. And nextis 52 experiment papers and 41 clinical trials. 4. Type analysis on the type of illnesses listed in experiment papers, 81 for anti-cancer ${\cdot}$ immune disorders ${\cdot}$ anti-oxidation, 61 papers concentrated on arthritis, etc. Conclusion : Since 1984 to August 2006 issue ranging 22 years, type analysis revealed that the number of journals pertaining to pharmacopuncture has risen steadily over the years and nearly half of papers published recently are dealing with pharmacopuncture. Pharmacopuncture is a treatment method based on the unique theory of Korean traditional medicine. And effort and academical approach on pharmacopuncture are expected to receive positive evaluation.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.1
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• pp.81-87
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• 2010

In this paper, we have fabricated $SiO_2$ oxidation thin films by HDP-CVD(high density plasma-chemical vapor deposition) method for passivation layer or barrier layer of OLED(organic light emitting diode). We have control and estimate the deposition rate and relative index characteristics with process parameters and get optimized conditions. They are gas flow rate($SiH_4:O_2$=30:60[sccm]), 70 [mm] distance from source to substrate and no-bias. The WVTR(water vapor transmission rate) is 2.2 [$g/m^2$_day]. Therefore fabricated thin film can not be applied as passivation layer or barrier layer of OLED.

• Polymer(Korea)
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• v.35 no.5
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• pp.444-450
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• 2011

A high molecular weight natural sodium alginate (HMWSAs) was depolymerized by hydrogen peroxide ($H_2O_2$) with ultrasonic irradiation. The effects of the reaction conditions such as reaction temperature, reaction time, hydrogen peroxide concentration and ultrasonic irradiation time on the molecular weights and the end groups of the depolymerized alginates were investigated. It was revealed that depolymerization occurred through the breakage of 1,4-glycosidic bonds of sodium alginate and the formation of formate groups on the main chain under certain conditions. The changes in molecular weight were monitored by GPC-MALS. The molecular weight of 2 wt% alginate solution decreased from 450 to 15.9 kDa for 0.5 hrs at 50 $^{\circ}C$ under an appropriate ultrasonic irradiation. The PDI(polydispersity index)s of the alginate depolymerized in this study were considerably narrow in comparison with those obtained from the other chemical degradation method. The PDIs were in the range of 1.5~2.5 in any reaction conditions employed in this study.

• Journal of Microbiology and Biotechnology
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• v.22 no.7
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• pp.1005-1014
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• 2012

The understanding of the relationship between ammonia-oxidizing bacteria (AOB) communities in activated sludge and the operational treatment parameters supports the control of the treatment of ammonia-rich wastewater. The modifications of treatment parameters by alteration of the number and length of aerobic and anaerobic stages in the sequencing batch reactor (SBR) working cycle may influence the efficiency of ammonium oxidation and induce changes in the AOB community. Therefore, in the research, the impact of an SBR cycle mode with alternating aeration/mixing conditions (7 h/1 h vs. 4 h/5.5 h) and volumetric exchange rate (n) on AOB abundance and diversity in activated sludge during the treatment of anaerobic sludge digester supernatant at limited oxygen concentration in the aeration stage (0.7 mg $O_2/l$) was assessed. AOB diversity expressed by the Shannon-Wiener index (H') was determined by the cycle mode. At aeration/mixing stage lengths of 7 h/1 h, H' averaged $2.48{\pm}0.17$, while at 4 h/5.5 h it was $2.35{\pm}0.16$. At the given mode, AOB diversity decreased with increasing n. The cycle mode did not affect AOB abundance; however, a higher AOB abundance in activated sludge was promoted by decreasing the volumetric exchange rate. The sequences clustering with Nitrosospira sp. NpAV revealed the uniqueness of the AOB community and the simultaneously lower ability of adaptation of Nitrosospira sp. to the operational parameters applied in comparison with Nitrosomonas sp.

• Reproductive and Developmental Biology
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• v.37 no.4
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• pp.281-287
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• 2013

In mammal, unfertilized oocytes remain in the oviduct or under in vitro culture, which is called "oocyte aging". This asynchrony negatively affects fertilization in pre- and post-implantation embryo development. Caffeine a phosphodiesterase inhibitor is known to rescue oocyte aging in several species. The objective of this study is to determine the cytoskeleton distribution in aged oocytes and the embryo developmental ability of aged oocytes in the present or absence of caffeine during maturation. Caffeine treatment increased the incidence of normal spindle assembly of aged oocytes (treatment, $67.57{\pm}4.11%$ aging, $44.61{\pm}6.4%$) and no significant differences compared to control group. Fluorescence values were compared using ROS (Reactive oxidation species) stain. Fluorescence values appear of control group intensity rate ($51.53.{\pm}3.80$), aging group ($68.10{\pm}5.54$) and treatment of caffeine ($45.04{\pm}2.98$). Aged oocytes that were derived from addition of caffeine to the IVM (in vitro maturation) medium had significantly increased 2-cell that developed to the blastocyst stage compared to the aging group. Blastocysts, derived from caffeine treatment group, significantly increased the total cell number compare aging ($90.44{\pm}10.18$ VS $67.88{\pm}7.72$). Apoptotic fragments of genomic DNA were measured in individual embryo using TUNEL assay. Blastocyst derived from caffeine treatment group decreased significantly the apoptotic index compared to blastocyst derived from aging group. In conclusion, we inferred that the caffeine treatment during oocyte aging can improve the developmental rate and quality in bovine embryos developing in vitro.

• Journal of the Korean institute of surface engineering
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• v.49 no.3
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• pp.307-315
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• 2016

The properties of AlTiN films by a cathodic arc deposition process have been studied. Oblique angle deposition has been applied to deposit AlTiN films. AlTiN films have been deposited on stainless steel (SUS304) and cemented carbide (WC) at a substrate temperature of $500^{\circ}C$. AlTiN films were analyzed by scanning electron microscopy, glow-discharge light spectroscopy, micro-vickers hardness, and nanoindenter. When applying a current of 50 A to the cathodic arc source, it showed that the density of macroparticle of AlTiN films was 5 lower than other deposition conditions. With the increase of the bias voltage applied to the substrate up to -150 V, the density of macroparticle was decreased. The change of the $N_2$ flow rate during coating process made no influence on the film properties. For the multi-layered films, the film prepared at oblique angle of $60^{\circ}$ showed the highest hardness of 28 GPa and $H^3/E^2$ index of 0.18. AlTiN films have been shown a good oxidation resistance up to $800^{\circ}C$.