• Korean Journal of Environment and Ecology
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• v.27 no.2
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• pp.219-229
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• 2013

This research is performed in order to suggest seasonal effective research time that is applied to wild birds research which lives in a forest. The subject area of this research is Mulgun-ri village forest in Samdong-Myeon, Namhe-gun. To investigate suitability of the project, existing land-use, existing vegetation, vegetational structure, and etc. of the subject and whole area are figured out. To suggest adequate research time, based on seasonal sun rise and set time for 3days, repetitive research is performed at hourly intervals. The subject area is connected with a forest and is possible for forest wild birds to flows in and provides various habitats and feeding areas. And also the subject area is a appropriate area for wild birds research and is like a natural forest in that a layer structure development of the forest itself, a distribution of Zelkova serrata and Aphananthe aspera and so on. 105 species which is observed in subject area are categorized and mountain birds are classified. After time-based peak value is selected in each season, hourly species richness, diversity, and index of similarity are analyzed as compared with the appearing number of species and individual bird. As a result, 7~11 hour is the most effective time in spring, and 8~9 hour is the best time. In summer, 6~9 hour is the most appropriate time when whole appearing species are similar to species structure. In fall, 7~11(30~60 minutes after sun rise) when wild birds movements are vigorous is analyzed easy to observe and 8~9 hour is the most appropriate research time because each analysis shows the best values. In winter, 7~12 hour is the most effective time although 10~11 hour is the best time but it is decided that similar results are drawn because hourly deviation is not so big except 1 hour before sun rise. In every four season, it is decided that 30~60 minutes after sun rise is appropriate to research a group of wild birds in the subject area.

• Journal of radiological science and technology
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• v.37 no.4
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• pp.239-246
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• 2014

Filter absorbs low-energy X-ray to increase the average energy and reduces patient exposure dose. This study investigates if the materials of Mo and W could be used for the digital imaging device CR by conducting image assessment and dose measurement of SNR, FOM and histogram. In addition, measurement of beam quality was conducted depending on the material of the filter, and at the same time, a proper combination of filters was examined depending on the change in tube voltage (kVp). In regard to entrance skin dose, Mo filter showed the dose reduction by 42~56%, compared to Cu filter. Moreover, Mo filter showed higher transmission dose by around 1.5 times than that of Cu filter. In image assessment, it was found that W was unsuitable to be used as a filter, whereas Mo could be used as a filter to reduce dose without decline in image quality at the tube voltage of 80 kVp or higher. As tube voltage increased, 2.0 mm Al+0.1 mm Mo almost had a similar histogram width to that of 2.0 mm Al+0.2 mm Cu. Therefore, Mo filter can be used at relatively high tube voltage of 80 kVp, 100 kVp and 120 kVp. The SNR of 2.0 mm Al+0.1 mm Mo did not show any significant difference from those of 2.0 mm Al+0.2 mm Cu and 2.0 mm Al+0.1 mm Cu. As a result, if Mo filter is used to replace Cu filter in general radiography, where 80 kVp or higher is used for digital radiation image, patient exposure dose can be reduced significantly without decline in image quality, compared to Cu filter. Therefore, it is believed that Mo filter can be applied to chest X-ray and high tube voltage X-ray in actual clinical practice.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.877-882
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• 2015

This study was carried out treatment of polyethylene glycol (PEG) in order to increase of survival rate of acclimated plants of strawberry's in vitro plantlets through bioreactor culture. We used PEG with molecular weight 6000 (PEG 6000) in this study. Concentration of PEG is non-treatment, 5, 10, 15, and $20g{\cdot}L^{-1}$ each bioreactor. $5g{\cdot}L^{-1}$ of PEG was treated at $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$, and $5^{th}$ week during culture. We investigated growth characteristics of in vitro plantlets after 6 weeks cultivation. Growth amount of all PEG treatment decreased as compared to non-treatment. The more concentration increased, the more plant growth decreased. In $5g{\cdot}L^{-1}$ of PEG, shoot length was shorter than non-treatment that shoot length was 7.9 cm and especially fresh weight that is 1.6 g was more decrease than non-treatment. Shoot length was ranged 3.0-3.9 cm at $1^{st}$ week treatment to $4^{th}$ week treatment of $5g{\cdot}L^{-1}$ PEG. The shoot length was not significant by 5.3 cm at $5^{th}$ week treatment. The survival rate was improved 5.4% at the treatment of $4^{th}$ week and was improved 8.7% at the $5^{th}$ week as compared to non-treatment. In order to improve of survival rate of strawberry' in vitro plantlets through bioreactor culture, the method is suitable that adding $5g{\cdot}L^{-1}$ of PEG in the medium and $5^{th}$ week's treatment is suitable.

• Journal of radiological science and technology
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• v.38 no.3
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• pp.305-313
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• 2015

After Fukushima Daiichi nuclear disaster in 2011, study and maintenance of monitoring systems have been made at home and abroad. As concerns about radioactive contamination of water have increased in Korea, update of maintenance of managing radioactive materials in water is being made mainly by Ministry of Environment. In this study, we analysed current state of monitoring system modification in Japan, the country directly involved and neighboring country. According to the result, Japan modified the legislations first. Then Ministry of Education, Culture, Sports, Science and Technology (MEXT) provides theoretical background of radiological monitoring. And Ministry of the Environment actually watches state of water pollution in public waters and underground water. Finally related agencies like local government are monitoring current state of radioactive contamination in water environment. By region, local monitoring stations share the investigation of the whole country. Also, additional monitoring is running around nuclear facilities. After Fukushima disaster, monitoring for area near Fukushima is added. Among the reference levels, management target value of drinking water and tap water is 10 Bq/kg, and those of public water and underground water are 1 Bq/L. Measuring intervals varied from every hour to once a year, regularly or irregularly depending on the investigation. The main measuring items are air dose rate, gross ${\alpha}$, gross ${\beta}$, ${\gamma}$ radionuclide, Cs-134, Cs-137, Sr-89, Sr-90, I-131, and so on. In comparison, regulations about general public water in Korea need to be modified, while those about area near nuclear facility and drinking water are organized well. In future, therefore, domestic system would be expected to be modified with making reference to the guidelines like WHO's one. As good case of applying international guideline to domestic environment, Japanese system could be a reference when general standard of radioactivity in public water is made in Korea.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.7
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• pp.892-901
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• 2009

This study confirmed depletion efficiency of nitrite when incubate lactic acid bacteria was isolated from commercial Chinese cabbage pickles (Baechu kimchi), pickled ponytail radishes (Chongkak kimchi), radish cube kimchi (Kaktugi) and pickled Wakegi (Pa kimchi) at temperatures of $15^{\circ}C$ and $25^{\circ}C$. At $15^{\circ}C$, lactic acid bacteria isolated from commercial kimchi depleted nitrite actively except Leuconostoc mesenteroides subsp. mesenteroides and Leuconostoc paramesenteroides. In particular, Leuconostoc mesenteroides subsp. dextrinicum and Leuconostoc lactis depleted nitrite by very actively without period adaptation in nitrite. Lactobacillus sake, Lactobacillus plantarum, Lactobacillus casei subsp. pseudoplantarum, and Lactobacillus coryniformis subsp. torquens depleted nitrite very actively after 1 day. L. mesenteroides subsp. mesenteroides depleted nitrite relatively actively after 2 days pass. In contrast, L. paramesenteroides displayed very low nitrite depletion ratio compared to other species. At $25^{\circ}C$, all lactic acid bacteria isolated from commercial kimchi did not need adapting period in nitrite, and depleted nitrite very actively except L. paramesenteroides. Also, all lactic acid bacteria except L. mesenteroides subsp. mesenteroides and L. paramesenteroides nitrite of more than 90% after 1 day, and L. mesenteroides subsp. mesenteroides depleted nitrite of more than 90% after 2 days. However, because L. paramesenteroides was not active even at $25^{\circ}C$, nitrite depletion efficiency was very low compared to other species. On the other hand, the same species of Lactobacilli and Leuconostocs except L. mesenteroides subsp. mesenteroides and L. paramesenteroides of other kimchi origin at $15^{\circ}C$ as well as $25^{\circ}C$ by vitality depleted nitrite very actively without statistically significant difference (p<0.05).

• Journal of Animal Science and Technology
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• v.46 no.1
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• pp.39-48
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• 2004

This experiment was conducted to investigate the effect of continuous feeding of probiotics on growth performance, nutrient digestibility, blood urea nitrogen(BUN) and immune responses in pigs. Treatments were 1) Control(basal diet), 2) P-O.l(basal diet + 0.1% probiotics) and 3) P-0.2(basal diet + 0.2% probiotics). In growth trial, a total of sixty pigs(6.17 $\pm$ 0.45 kg average body weight) weaned at 21 days of age were used. All pigs were assigned according to sex and body weight, and each treatment had 5 replicates of 4 pigs per pen in a randomized complete block(RCB) design. During 0${\sim}$8 weeks, there was no significant difference in average daily gain(ADG), average daily feed intake(ADFI) and gain:feed ratio(GfF) among treatments. During 9 - 20 weeks, ADG was improved significantly in pigs fed P-O.I or P-0.2 diets when compared to the pig fed control diet(P <0.05), but there was no significant difference in ADFI and GfF ratio. During overall period, ADG, ADFI and GfF ratio were not significantly different among treatments. In the first metabolic trial(17.93 $\pm$1.45kg average body weight), apparent digestibility of OM, protein, fat in pigs fed P-O.l and P-0.2 diets were greater than in pigs fed control diet(P <0.05) and ash digestibility in pigs fed P-0.2 diet was significantly higher than in pigs fed control diet(P <0.05). Calcium digestibility in pigs fed P-0.2 diet was significantly higher than in pigs fed control and P-O.I diets(P <0.05). Fecal-N excretion was lower in pigs fed P-O.! and P-0.2 diets than in pigs fed control(P <0.05). In the second metabolic trial(41.80 $\pm$ 2.68kg average body weight), there was no significant difference among treatments in apparent digestibility of nutrients and N-retention. In blood assay for the BUN and immune responses investigations, there was no significant difference among treatments during overall period of experiment. Therefore, this experiment suggested that probiotics supplementation could improve growth performance and nutrient digestibility of pigs.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.405-411
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• 2005

Chitosan, second largest biomass after cellulose on earth, has potential for use as functional food package due to its antibacterial activity. However, due to high melting temperature of chitosan, chitosan films have been made by casting method. Because gelatin has relatively low molting temperature depending upon amount of plasticizer added, it was added to chitosan to produce commercially feasible film. The objective of the current study was to determine optimum blend ratio and amount of chitosan/gelatin blend solutions against antibacterial activities for extruder resin. Gram-positive bacteria (Bacillus cereus ATCC 14579 and Listeria monocytogenes ATCC 15313) and -negative bacteria (Escherichia coli ATCC 25922 and Salmonella enteritidis IFO 3313) were used. Paper (8 mm) diffusion and optical density methods were used to evaluate effect of different blending ratio solutions on the inhibition of bacterial growth. Measured clear none size ranged from 8 mm to 18.07 mm in paper diffusion test. For B. cereus, E. coli, and S. enteritidis, addition of $50\;{\mu}L$ blend solution (chitosan/gelatin = 2/8: 0.3 mg) resulted in clear zone on paper disc. In L. monocytogenes, inhibition effect was observed with 0.6 mg chitosan (chitosan/gelatin=4/6). Minimum inhibitory concentration (MIC) values of B. cerues, L. monocytogenes, E. coli, and S. enteritidis with addition of chitosan were 0.1461, 0.2419, 0.0980, and 0.0490 mg/mL, respectively, These results indicate possibility of producing commercially feasible film with addition of optimum chitosan/gelatin amount.

• Korean Journal of Food Science and Technology
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• v.39 no.2
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• pp.138-145
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• 2007

The effects of amylopectin and hydrocolloid (locust bean gum and guar gum) content on wheat flour dough and noodle properties were investigated. As the amount of amylopectin increased, the water absorption rate (farinograph), the tension (tension test), the gel stability (freeze-thawing treatment), and the springiness and the cohesiveness (TPA) increased, but the pasting temperature (RVA), the lightness and yellowness (color measurement), and the hardness (TPA) tended to decrease. In sensory evaluations, the scores for cohesiveness, springiness, and acceptability of cooked noodle increased as the proportion of amylopectin increased. The proper combination of amylose/amylopectin ratio and hydrocolloids improved the freeze-thaw stability and the sensory acceptability of wheat flour dough and noodle.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.22 no.3
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• pp.95-102
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• 2016

This study investigated the effects of the oxygen permeability of vacuum packaging film and the storage temperature on the quality and shelf life of Hamburg steaks during storage for 14 days. Control samples (C) were packaged in a polyamide/polyethylene (PA/PE) film and stored at $5^{\circ}C$. Treatment samples were either packaged in an ethylene vinyl alcohol/polyethylene (EVOH/PE) copolymer film and stored at $5^{\circ}C$ (T1), and in a PA/PE film and stored at $-18^{\circ}C$ (T2). The initial total plate count (TPC) was 3.6 log cfu/g. In T1 samples, TPC and Brochothrix thermosphacta counts were increased, similar to those in C samples, whereas Pseudomonas spp. counts were significantly lower than those in C samples during storage. Over the storage period, the volatile basic nitrogen values increased most rapidly in C samples, followed by T1 and then T2 samples. The values of thiobarbituric acid reactive substances steadily increased in all samples during storage. The colour parameters were not significantly different among the samples during storage. T1 samples maintained sensory qualities in flavour and off-odour parameters for two days longer than C samples did. At day 12, T2 samples were evaluated as being below the marketability score of 5.0 for texture. In conclusion, using high oxygen barrier films like EVOH/PE copolymer for packaging Hamburg steaks could extend the sensory qualities in view of flavour and off-odour during chilled storage. However, frozen storage at $-18^{\circ}C$ is recommended when the storage period is extended beyond 14 days at $5^{\circ}C$.

• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.569-576
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• 2003

An experiment was conducted to investigate the effect of microbial phytase (Natuphos$^{\circledR}$) supplementation, individually and in combination with carbohydrase enzyme complex (composed of enzymes targeted to SBM dietary components such as $\alpha$-galactosides and galactomannans; ENDO-POWER$^{\circledR}$) to corn-soy basis diet with low nutrient levels on growth performance and nutrient digestibility of growing pigs. A total of 48 crossbred weaned pigs (Landrace${\times}$Yorkshire${\times}$Duroc), 29.1$\pm$0.14 kg of initial body weight, were randomly allotted to four dietary treatments, based on weight and age, according to a Randomized Complete Block Design. There were three pens per treatment and 4 pigs per pen. The dietary treatments were 1) CON (control diet with 3,380 kcal/kg of metabolizable energy, 18.96% of crude protein, 1.10% of lysine, 0.75% of calcium and 0.35% of available phosphorus), 2) LP+NTPS (CON diet with 0.15% unit lower available P levels+0.1% phytase (500 FTU/kg; Natuphos$^{\circledR}$)), 3) LEL+ENP (CON diet with 3.0% unit lower ME and lysine levels + 0.1% carbohydrase enzyme complex (ENDO-POWER$^{\circledR}$), and 4) LPEL+ENZ (CON diet with 0.15% unit lower available P levels and 3.0% unit lower ME and lysine levels+0.1% ENDO-POWER$^{\circledR}$ and 0.1% Natuphos$^{\circledR}$ (500 FTU/kg). There was no significant difference (p〉0.05) in average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR) among dietary treatments during the whole experimental period (0 to 4 weeks). Apparent digestibility of gross energy was greater in LP+NTPS and LPEL+ENZ groups than in the LEL+ENP (p<0.05). Apparent digestibility of phosphorus was greater in LP+NTPS than in LEL+ENP (p<0.05). Dry matter excretion was lowest in LPEL+ENZ and phosphorus excretion was lowest in LP+NTPS (p<0.05). Overall, pigs fed on LPEL+ENZ group tended to have better nutrient digestibility (dry matter, gross energy, crude protein and phosphorus) than pigs fed on control group. All dietary enzyme treatment groups showed lower feed cost/body weight gain of pigs than control group. In conclusion, the results from the present study suggest that the simultaneous inclusion of phytase and carbohydrase enzyme complex to diets is advantageous with respect to reducing nutrient excretion of growing pigs and may contribute to increased economic return when added to corn-soy based growing pig diets.