• 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.

• Journal of Forest and Environmental Science
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• v.39 no.1
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• pp.20-26
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• 2023

Cow pea (Vigna unguiculata) was intercropped with Ziziphus spina-christi as summer forage in two consecutive seasons of 2017 and 2018. The aims to find out suitable agroforestry practice for saline soils of Khartoum State. And to investigate effect of tree spacing on forage biomass yield under semi -irrigated systems. Completely randomized block design with 3 replicates was conducted for this trial. Thus Z.spina-christi that fixed at 4×4 m was intercropped with cowpea at 1 m and 1.5 m spacing from trees trunk. Tree growth parameters were measured in terms of tree height, tree collar diameter, tree crown diameter and fruit yield per tree. While crop were parameters were determined in terms of plant height, number of plant, forage biomass yield per ha and land equivalent ratio. Soil profile of 1×1 m and 1.5 m depth was excavated and its features were described beside its chemical and physical properties were analyzed for 0-10 cm, 0-30 cm, and 30-60 cm and 60-100 cm layers. The results revealed that soil pH, CaCO₃, SAR, ESP, and EC ds/m were increased by increasing soil depths. Meanwhile tree growth in terms of tree height was significant in the first season 2017 when compared with tree collar diameter and tree crown diameter. Also significant differences were recorded for tree growth when compared with sole trees in the second season in 2018. Tree fruit showed marked variations between the two seasons, but it was higher under intercropping particularly at ZS2. Crop plant height was highly significant under sole cropping than intercropping in first season in 2017. In contrast forage biomass yield was significant under intercropping in ZS1 and ZS2 treatments. Land equivalent ratio was advantageous under this agroforestry system particularly under ZS2. Thus it recorded 5 and 9 for ZS2 in the two consecutive seasons respectively. Therefore, it is feasible to introduce this agroforestry system under such arid lands to provide summer forage yield of highly nutritive value and low cost for animals feed as well as to increase farmers' income and to halt desertification and to sequester carbon.

• Journal of Chest Surgery
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• v.36 no.12
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• pp.894-903
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• 2003

Protection against ischemia-reperfusion injury is crucial for successful transplantation of the lung. It has been known that nitric oxide has many favorable effects on the donor lungs but at the same time, has some potential side effects of cytotoxicity. In this regards, we investigated whether the administration of nitroglycerin could decrease ischemia-reperfusion injury in isolated rat lung reperfusion model for the confirmation of the effect of nitroglycerin, a donor of nitric oxide, on lung transplantation. Material and Method: 35 Sprague-Dawley species male white rats were used for this experiment. For nitroglycerin group (n=18), nitroglycerin was administered intravenously followed by mixed in flushing solution for preservation. As a control group (n=17), we used the same amount of normal saline. To evaluate the effect of nitroglycerin on the lung, heart-lung block was obtained, weighed and stored in University of Wisconsin Solution at 1$0^{\circ}C$ for 24 hours. In each group of the isolated lungs, reperfusion was carried out with Krebs-Hensleit-diluted human blood for 60 minutes. As parameters of the state of the isolated lung, peak inspiratory and pulmonary arterial pressures were continuously recorded. Oxygen and carbon dioxide tension of reperfusing blood were measured before and after 30, 60 minutes of reperfusion. After sixty minutes of reperfusion, protein content in bronchoalveolar lavage fluid was measured also for the evaluation of the degree of alveolar flooding. Lung myeloperoxidase activity was determined to verify the accumulation of neutrophils. Results: Although statistically significant differences were not noted in peak inspiratory and pulmonary arterial pressure between control and nitroglycerin group, latter group showed lowering tendency of pulmonary arterial pressure during the entire reperfusion period. Oxygen tension was higher (p<0.05) in nitroglycerin group compared with that of the control group, in contrast, there were no differences in carbon dioxide tension, protein content in bronchoalveolar lavage fluid and myeloperoxidase activity between the groups. In the examination of ultrastructural changes, nitroglycerin denoted the protective effect on the pulmonary architecture compared with that of control group. Conclusion: Collectively, on the bases of these experimental results, prior treatment of donor lung with nitroglycerin could result in better preservation of the lung. Consequently, these nitroglycerin preserved lungs are thought to be more suitable for successful transplantation of the lung.