• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.174-177
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• 1993

Ultara violet ray air cleaner to use as the sterilization and deodorization device in refrigerator was designed and made of UV lamp and carbon block as the main components. The intensity of the lamp was $2.38\;mW/cm^2$ and reflector was installed to increase the radation. After running the device for 12 hours, 80% of the population of airborn bacteria was sterilized both at 48 and 480 liter refrigerator chambers. Ozone production caused by UV-ray reached 0.082 ppm at holding section within a few second when the device was operated at $25^{\circ}C$ and it showed 0.06 pm at $3^{\circ}C$. Deodorization effect was 2.5 times greater than that of a device made of electrical are principle at $25^{\circ}C$. New device 2 times more effectivly decreased trimethylamine and methyl mercaptan content applied as odor indicator substance in chamber at $3^{\circ}C$ than electrical arc type.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1256-1266
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• 2004

2-Bromooctanoic acid (2-BrOA) is known to block the formation of polyhydroxyalkanoic acid (PHA) in Pseudomonasfluorescens BM07 without any influence on the cell growth when grown on fructose, but it inhibits the cell growth when grown on octanoate (OA) (Lee et al., Appl. Environ. Microbiol. 67: 4963- 4974, 2001). We investigated the role of 2-BrOA in the PHA synthesis of the bacterium grown with mixtures of fructose and fatty acids. OA, 11­phenoxyundecanoic acid (1 1-POU), and 5-phenylvaleric acid (5-PV) were selected as model substrates. When supplemented with 50 mM fructose, all these carboxylic acids suppressed the formation of PHA from fructose, however, the ~-oxidation coenzyme A monomers derived from the carboxylic acids were efficiently polymerized, but the conversion yield [(mol of carboxylate substrate converted into PHA)/(mol of carboxylate substrate in the feed)] was low (e.g., maximally $\~53\%$ for 5 mM 11-POU). Addition of 2-BrOA (up to 5 mM) to the mixed carbon sources raised the conversion yield sensitively and effectively only at low levels of the acid substrates (e.g., 2 mM 1 1-POU or 5 mM OA): For instance, $100\%$ of 2 mM ll-POU were converted into PHA in the presence of 5 mM 2-BrOA, whereas only $\~10\%$ of the 1 1-POU were converted in the absence of 2-BrOA. However, at highly saturated suppressing levels (e.g., 5 mM ll-POU), 2-BrOA inhibitor showed no significant additional effect on the conversion ($60- 70\%$ conversion irrespective of 2-BrOA level). The existence of competitive and compensative relationship between 2­BrOA and all the carboxylic acid substrates used may indicate 'Present address: Section on Brain Physiology and Metabolism, Bldg. 10, Rm. 6N202, National Institute on Agmg, National Institute of Health, Bethesda, MD 20892, U.S.A. that all the acid substrate-derived inhibiting species bind to the same site as the 2-BrOA inhibiting species does. We, therefore, suggest that 2-BrOA can be used for efficiently increasing the yield of conversion of expensive substituted fatty acids into PHA and then substituted 3-hydroxyacids by hydrolyzing it.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.1
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• pp.1-9
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• 2018

Visibility is very poor in tunnel fire because of confined space where the fire may easily lead to the mass casuality incident because of fast smoke spread. In this test, air curtain and the fan were installed at rescue station in a bid to make use of rescue station in safe way during the train fire in undersea tunnel and a full-scale fire test was conducted to identify the applicability of air curtain system. Air curtain system was installed at a real rescue station and the test was continued for 2 minutes till heptane which was used as fire source was completely burned out. When air curtain was working, difference in temperature between inside and outside the platform was $160^{\circ}C$ and carbon monoxide measured inside the platform was less than the case of no air curtain system by 160 ppm. Thus a full-scale fire test demonstrated that the air curtain system installed at rescue station in undersea tunnel was able to effectively block the heat and smoke generated from the fire.

• Journal of Veterinary Clinics
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• v.33 no.4
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• pp.234-236
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• 2016

A 14 kg, 9-year-old, spayed female, Cocker Spaniel was presented to the Veterinary Medical Teaching Hospital of Seoul National University with a history of head tilt and circling. Otitis externa and media were diagnosed by computerized tomography, and total ear canal ablation was performed. In preanesthetic evaluation, systemic hypertension and second-degree atrioventricular block were observed, but there was no regurgitation through the heart valves. Systemic hypertension was managed with amlodipine (0.1 mg/kg, PO, BID) for the anesthesia. The dog was premedicated with cefazolin (22 mg/kg, IV) and midazolam (0.2 mg/kg, IV). Anesthesia was induced with alfaxalone (2 mg/kg, IV) and maintained with isoflurane and 100% oxygen following intubation. During surgery, vital signs (heart rate, respiratory rate, blood pressure, end tidal carbon dioxide partial pressure and body temperature) were maintained within normal ranges, but bradycardia was observed and corrected with glycopyrrolate (5 ug/kg IV, twice). During subcuticular suture, electrohemostasis was applied at the incision line, which was close to the trigeminal nerve. In no time at all, heart rate dramatically decreased from 110 to 60 beats per minute. No additional treatment was done because mean blood pressure was maintained above 70 mmHg. The heart rate recovered according to the decrease of end tidal isoflurane concentration and there were no complications associated with the anesthesia and surgery. Sudden bradycardia after electrical stimulation around the trigeminal nerve was considered as trigeminocardiac reflex (TCR). It is recommended to be careful of bradycardia from TCR when electrocautery is used in the craniofacial area during surgery.

• Parasites, Hosts and Diseases
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• v.40 no.1
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• pp.45-54
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• 2002

Field trials evaluating selected commercially available mosquito traps variously baited with light, carbon dioxide, and/or octenol were conducted from 18-27 September 2000 in a malarious area near Paekyeon-ri (Tongil-Chon) and Camp Greaves in Paju County, Kyonggi Province, Republic of Korea. The host-seeking activity for common mosquito species, including the primary vector of Japanese encephalitis, Culex tritaeniorhynchus Giles. was determined using hourly aspirator collections from a human and propane lantern-baited Shannon trap doting hours when temperatures exceeded $15^{\circ}C$. The total number of mosquitoes and number of each species captured during the test was compared using a block design. Significant differences were observed for the total number of mosquitoes collected, such that, the Mosquito MagnetTM with octenol > Shannon trap > ABC light trap with light and dry ice > Miniature Black Light trap (manufactured by John W. Hock) $\geq$ New Jersey Trap > ABC light trap with light only. Significant differences in numbers collected among trapes were noted for several species including: Aedes vexans (Meigen), Anopheles lesteri Baisas and Hu. An. sinensis Weidemann, An. sineroides Yamada, An. yatsushiroensis Miyazaki. Culex pipiens pallets Coquillett L., Cx. orientalis Edwards and Cx. tritaeniorhynchus. Host-seeking activity for most common species showed a similar bimodal pattern. Results from these field trap evaluations can significantly enhance current vector and disease surveillance efforts especially for the primary vector of Japanese encephalitis, Cx. tritaeniorhunchus.

• Journal of Conservation Science
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• v.27 no.3
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• pp.313-322
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• 2011

The floral wall of Lee Sang-beom's House and Atelier, which is No. 171 of the Registrated Cultural Heritage was conserved. In addition, materials characteristics and manufacturing technique have revealed through the scientific analysis. As a result of the analysis, samples were divided into three sections; the support layer that is made from block bricks, the paint layer and the cement mortar layer on the paint layer for the reinforcement of the construction. The higher layer lies, the finer grains it has. Furthermore, a little it was generated a small quantity of pores and calcium carbonates ($CaCO_3$) generated due to aeration of cement mortar. The patterns of letters, animals and plants pattern were expressed in the paint layer by relief and openwork. The results of qualitative analysis of the pigments of the paint layer were detected components of carbon black (C), Fe oxide ($Fe_2O_3$) and oyster shell white ($CaCO_3$, or quicklime). On the other hands, as the conservation of the floral wall, stainless frames were set up for the structural stability, the cement mortar were removed from the surface and the partly damaged and cracked areas were filled with KSE Filler A, B.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.1
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• pp.81-89
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• 2018

Austenitic stainless steels have excellent corrosion resistance, durability and fire resistance. Especially, since STS304L among austenitic types is a low-carbon variation of STS304 and has excellent intergranular corrosion resistance, it can often be used under the welded condition without heat treatment after field welding. This paper investigated ultimate behaviors such as ultimate strength and weld metal fracture mechanism of STS304L fillet-welded connections with TIG(tungsten inert gas) welding through test results. Main variables of specimens are weld length and welding direction against loading. Fracture of specimens are classified into three modes(tensile fracture, shear fracture and block shear fracture). Ultimate strengths were compared according to the welding direction and weld length and TFW series with transverse fillet weld had the highest strength compared with other types(LFW series with longitudinal fillet weld and FW series with all round weld). It is known that current design specifications such as KBC 2016 and AISC2010 underestimated the strength of TFW and LFW specimens and provided unconservative estimates for FW specimens. Finally, strength equations were proposed considering material properties of STS 304L material.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.4
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• pp.729-738
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• 2017

With the signing of the Paris Agreement, which is the new climate change agreement at the end of 2015, it will have a great impact on Korea environmental policy. The construction industry, which accounts for 42% of Korea's total $CO_2$ emissions, has been implementing various policies to improve the environmental problems. However, it is only applying passively to other projects except eco-friendly building certification. This is because most of the eco-related systems are based on building facilities. Therefore, there is a need for a new eco - friendly design evaluation model that can be widely applied not only to architecture but also to civil engineering facilities. In this study, a new model is developed based on the existing VE model, which adds new factors to evaluate the environmental friendliness, potential environmental pollution concept and environmental risk of facilities. This model is an eco-friendly design evaluation model that enables decision makers to effectively select alternative environmental criteria at the design stage. As a result of the case analysis of the block retaining wall and the alternative retaining wall, the value of the eco - friendly value of the alternative was 1.026 times higher than the original one. If this model is used at the design stage, it is expected to contribute not only to the construction of environmentally friendly facilities but also to the reduction of carbon emissions.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.3
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• pp.213-218
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• 2014

Effects of elevated $CO_2$ on leaf phenology of Quercus acutissima were examined using open-top chambers, which had ambient and elevated $CO_2$ concentrations (ambient ${\times}1.4$, ambient ${\times}1.8$). To analyze the effect of chamber, non-treatment block was established near outside of the chambers. In 2013, budburst, leaf unfolding, coloring, and shedding were surveyed, and spring phenology was surveyed in 2014. Thermal sum (base temperature $+5^{\circ}C$) of each phenological event occurred was recorded. In addition, bud samples were collected and analyzed for carbohydrate contents in March 2014. Elevated $CO_2$ concentration advanced budburst and leaf unfolding, and delayed shedding in 2013. However, in 2014, the temperature of the spring season was high, and there was no significant effect of elevated $CO_2$ concentration on spring phenology. Carbohydrates content, such as starch, total non-structural carbohydrate and total soluble sugar, were significantly increased in response to elevated $CO_2$ concentration. It has been proposed that elevated $CO_2$ concentration could extend the growing season of temperate species with increased possibility of frost damage due to early bud opening and leaf unfolding. However, our analysis showed that the increased carbohydrate concentration in bud under elevated $CO_2$ would reduce the possibility of early spring frost damage by acting as cryoprotectant.

• Korean Journal of Organic Agriculture
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• v.29 no.2
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• pp.241-256
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• 2021

The current study was to evaluate the antioxidant activity of Phyllostachys bambusoides (PHB) as a feed additives and investigate whether its antioxidant activity could be helpful for increasing rumen fermentation characteristics and methane reduction. The antioxidant activity results showed that total polyphenols and flavonoids contents were 43.54 ± 8.68 mg CE/g and 17.13 ± 0.45 mg QE/g, respectively, and the IC₅₀ values for 1,1-diphenyl-2-prcrylhydrazyl (DPPH) and 2,2'-azino-bis (3- ethylbenzthiazoline-6- sulphonic acid) (ABTS) radical scavenging activity were 163.13 ± 19.25 ㎍/mL and 97.07 ± 4.46 ㎍/mL, respectively. Two heads of cannulated Hanwoo (450 ± 30 kg), consuming timothy hay and a commercial concentrate (60:40, w/w) twice daily (at 09:00 and 17:30) at 2% of body weight, with free access to water and a mineral block, were used as rumen fluid donors. An in vitro incubation experiment was performed after 6, 12, 24, 48, and 72 hr with PHB added at concentration of 2, 4, and 6% of timothy hay basis. Total gas emission decreased as the amount of PHB addition increased at 6 and 24 hr of incubation. However, PHB addition did not affect total volatile fatty acid production, and methane and carbon dioxide emission also decreased as the amount of addition increased at 48 hr of incubation. Therefore, PHB was expected to be used as methane reducing additives in the ruminants.