• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.383-390
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• 2013

Mistlero C was shown to be non-genotoxic in a series of genotoxicity tests, including a bacterial reverse mutation test and a combined in vivo mammalian erythrocyte micronucleus test. In a bacterial reverse mutation assay, no significant increases in the number of revertant colonies, compared to the negative control, was detected in $5,000{\mu}g/plate$ of Mistlero C. In addition, with Mistlero C, no changes were shown in the number of micronucleated polychromatic erythrocytes (MNPCE) among 2,000 polychromatic erythrocytes compared to the negative control. Mistlero C was administered orally in rats to investigate acute toxicity. The $LD_{50}$ values in rats were above 2,000 mg/kg. In a repeated dose, 13-week, oral toxicity study conducted in rats, no compound-related adverse effects were shown at doses of Mistlero C of up to 1,000 mg/kg body weight/day. The results of these studies support the safe use of Mistlero C in food for human consumption.

• Fire Science and Engineering
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• v.30 no.4
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• pp.1-5
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• 2016

This research performed tests of Video Fire Detector and criteria of installation to make suggestions regarding the criteria that must be reflected in NFSC 203 by comparing the standards of FM Approvals, UL, ISO7240 and NFPA 72. FM Standard related to Video Fire Detector test has been classified as Smoke, Flame type, but the UL Standard has classified only as a Smoke type. This research examined 6 cases of fire phenomenon detection case in ISO 7240 and 3 cases in NFPA 72, respectively. There are 15 items required for the installation standard of a Video Fire Detector and each field standard is presented as a per installation method. To apply a Video Fire Detector, the pertinent items (the definition of term, detector's classification, structure and function among its test item) must be inserted. In addition, 7 items of the fire test, i.e., the sensitivity adjustment, prevent false alarm, ambient temperature test, the effective sensitivity and detection distance and viewing angle, aging test, flood test, must be applied to the actual test. For installation in the field, the operation environment and levels of illumination, and NFSC 203 must be set, and standards relevant to the sound system, indicators' installation distance, etc. need to be inserted.

• Fire Science and Engineering
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• v.30 no.4
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• pp.27-38
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• 2016

The paper reports the development of a distributed temperature sensing (DTS) system, which is a fire detection system using optical sensor linear detectors that depends on foreign and domestic technologies. This study accordingly analyzed the electrical signal patterns of Raman scattering light mainly used for temperature sensing among back-scattered light generated in optical fiber by using an oscilloscope. Through the measurement results, it could be verified that the Stokes signal patterns had little change by the temperature increase, but the temperature-sensitive anti-Stokes patterns had relative increase of the changes. This study developed a K-DTS system, which is an optical sensor linear fire detection system composed of an optical repeater and a receiver that can detect fires using Raman scattering light. It could be verified that the developed K-DTS system satisfied the type approval standards through the sensitivity tests using the rate of rise type and fixed temperature type sensitivity testers. In addition, performance experiments have been performed for performance evaluation of the K-DTS system developed in comparison with S-DTS system which has been imported from abroad and widely used in Korea. It can be confirmed from the results of the performance experiments using model tunnels that comparable performances can be obtained in fire detection locations and the measurements of fire temperatures.

• Membrane Journal
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• v.23 no.1
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• pp.1-11
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• 2013

Poly(ether imide) (PEI)-poly(dimethylsioxane) (PDMS) composite membranes and their modules were prepared, which are capable of selective $CO_2$ separation from the mixture gas. The gas flow rate, concentration, recovery ratio of $H_2$ and removal ratio of $CO_2$ outflowing by stage-cut were characterized at $25^{\circ}C$ and the constant pressure. In addition, to increase the recovery ratio of $H_2$, one stage, two stage series connection, and three stages series + parallel connection tests were carried out. When the stage-cut was 0.32 for the three stages connection operation, the concentration $H_2$ of the produced gas and the recovery ratio of $H_2$ was 97% and 85%, respectively. And also the removal ratio of $CO_2$ was 90% was obtained and the recycled gas concentration was similar with that of the feed gases.

• The Korean Journal of Mycology
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• v.40 no.4
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• pp.266-270
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• 2012

Stem canker and tuber rot symptoms were observed on yam grown in Andong and Jinju, Korea in 2011. A total of 20 isolates of Rhizoctonia and allied fungi were obtained from the symptomatic plants. Among the isolates, 8 isolates were identified as Rhizoctonia solani and 12 isolates as Ceratobasidium sp. based on rDNA-internal transcribed spacer (ITS) sequence similarity. In the cluster analysis of rDNA-ITS sequences, 7 isolates of R. solani belonged to AG 2-2IIIB and remaining one to AG 1-1A. In addition, among the 12 isolates of Ceratobasidium sp., 7 isolates belonged to AG-Fa, three isolates to AG-A and the other two isolates to AG-Fb and AG-O, respectively. Pathogenicity tests showed that all the R. solani AG 2-2IIIB isolates are pathogenic on stem and tuber of yam but R. solani AG 1-1A and all the Ceratobasidium isolates are non-pathogenic. The results indicate that R. solani AG 2-2IIIB is an important pathogen causing stem canker and tuber rot on yams grown in the study areas. This is the first report of R. solani AG 2-2IIIB causing stem canker and tuber rot of yam in Korea.

• International Journal of Highway Engineering
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• v.8 no.4 s.30
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• pp.87-99
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• 2006

This study was conducted to investigate whether the moisture variation aspects in pavement materials can be analyzed based on the convenient and reliable relative humidity(RH) measurement techniques. First, the ambient RH was measured using various sensors and the accuracies and calibration methods of the sensors were examined. Then, the RH of a cement mortar specimen was measured using the reliable sensors and the data was analyzed. In addition, the feasibility of using the RH measurement sensors to analyze the permeability of pavement materials was investigated. From this study, it was found that the Hygrochron was the most appropriate sensor to measure the RH of pavement materials, and the proper installation and calibration methods were developed. The RH of the cement mortar specimen tended to approach the ambient RH and was not much affected by the variation of the ambient RH. The specimen's RH variations at the surface and at the center showed a clear time lag. The RH measurement sensor was also found to be an appropriate tool for water permeability tests, and the methodologies to evaluate the permeability of pavement materials were proposed.

• International Journal of Highway Engineering
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• v.17 no.3
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• pp.85-95
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• 2015

PURPOSES : Recently, bonded concrete overlay has been used as an alternative solution in concrete pavement rehabilitation since its material properties are similar to those of the existing concrete pavements. Deteriorated concrete pavements need rapid rehabilitation in order to prevent traffic jams on Korean expressways. Moreover, speedy and effective repair methods are required. Therefore, the use of bonded concrete overlay with ultra-rapid hardening cement has increased in an effort to reopen promptly the expressways in Korea. However, mobile mixer is required for ultra-rapid hardening cement concrete mixing in the construction site. The use of mobile mixer causes various disadvantages aforementioned such as limitation of the construction supply, open-air storage of mixing materials, increase in construction cost, and etc. In this study, therefore, hydration accelerator in-situ mixing on polymer modified concrete produced in concrete plant is attempted in order to avoid the disadvantages of existing bonded concrete overlay method using ultra-rapid hardening cement. METHODS : Bonded concrete overlay materials using ultra-rapid hardening cement should be meet all the requirements including structural characteristics, compatibility, durability for field application. Therefore, This study aimed to evaluate the application of hydration accelerator in-situ mixing on polymer modified concrete by evaluating structural characteristics, compatibility, durability and economic efficiency for bonded concrete overlay. RESULTS : Test results of structural characteristics showed that the compressive, flexural strength and bond strength were exceed 21MPa, 3.15MPa and 1.4MPa, respectively, which are the target strengths of four hours age for the purpose of prompt traffic reopening. In addition, tests of compatibility, such as drying shrinkage, coefficient of thermal expansion and modulus of elasticity, and durability (chloride ions penetration resistance, freezing-thawing resistance, scaling resistance, abrasion resistance and crack resistance), showed that the hydration accelerator in-situ mixing on polymer modified concrete were satisfied the required criteria. CONCLUSIONS : It was known that the hydration accelerator in-situ mixing on polymer modified concrete overlay method was applicable for bonded concrete overlay and was a good alternative method to substitute the existing bonded concrete overlay method since structural characteristics, compatibility, durability were satisfied the criteria and its economic efficiency was excellent compare to the existing bonded concrete overlay methods.

• The Journal of Internal Korean Medicine
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• v.28 no.3
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• pp.434-441
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• 2007

Objectives : Peripheral neurodegeneration occurs in diabetes mellitus (DM), both sensory and motor nerve. but we don't know exactly if DM affects central nerve pathway for all studies. Electrophysiologic study is one of the most important diagnostic tools for diabetic neuropathy. Electroneurography and electromyography are usually used. but evoked potentials (EP) is more sensitive to small nerve fiber damages and useful for central nerve evaluation in addition to peripheral nerves. Most diabetic neuropathy studies by EP have been performed with somatosensory evoked potentials (SSEP). In contrast, the objective of this study is to investigate if DM targets central motor neurons by assessing the relation between fasting blood sugar (FBS) and motor evoked potentials (MEP) latency. Methods : We inspected the medical records of 34 patients who had MEP tests during admitting days. The latency from cervical portion to abductor pollicis brevis was used as peripheral motor conduction time (PMCT). and the latency from vertex to cervical portion was used as central motor conduction time (CMCT). Then, they were correlated to FBS using correlation analysis. Results : There was a significant linear relation between FBS and PMCT (Pearson's correlation coefficient r=0.487, p<0.01), but a poor linear relation between FBS and CMCT (Pearson's correlation coefficient r=-0.l97. p>0.05). Conclusions : This study suggests that prolonged latencies of MEP in DM may be due to peripheral neuropathy rather than dysfunction of central motor pathway. therefore the clinical use of MEP to diabetic neuropathy has to be divided segmentally.

• Parasites, Hosts and Diseases
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• v.27 no.1
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• pp.1-8
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• 1989

Serodiagnosis of parasitic infections is widely used, since parasites or their eggs are not always detected by ordinary methods. The sensitive tests such as ELISA are highly dependent on the purity of antigens used. To solve this problem. many workers have tried to find species-specific components of antigens, The present study was performed to determine the antigenic profile of crude saline extracts of 3, 5, 8 and 12-week old p. westermani worms, which were collected from experimentally infected cats, based on SDS-PAGE and immunoblot technique. The results were as follows: 1. The SDS-PAGE showed at least 30 Protein bands ranging from 229 kDa to 10 kDa molecular weight. The protein components of p. wsstermani changed chronologically during its developmental period. The 229 kDa band was recognized only in 12-week old worms ($$SEP_{l2}$). 2. Analysis by ELISA showed a significant increase in antibody levels at 3 weeks in infected cats using crude saline extract antigens ($SEP_3,{\;}SEP_5,{\;}SEP_8,{\;}SEP_{l2}$). 3. By EITB using $SEP_3$ and $SEP_5$ infected cats recognisea major protein bands with molecular weight of 60, 35, 28, 25 or 21 kDa at 3~12 weeks of infection, and 3 additional antigens, 19, 13 and 10 kDa, were detected at 8~12 weeks of infections. 4. Using $SEP_8$ 5 antigens, 91, 85, 31, 25 and 21 kDa, were consistently detected by all infected sera tested. In addition, 3 antigens of lg. 13 and 10 kDa were detected at 8~12 weeks of infection. Using $SEP_12$, similar results were obtained with that by using $SEP_8$ and 1 additional antigen of 229 kDa, specifically reacting with the sera from 12 weeks of in(traction, was recognized.

• Journal of the Korean Wood Science and Technology
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• v.28 no.3
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• pp.1-8
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• 2000

To develop the technology of producing structural board from low grade materials, an attempt was made to produce strand/particle composites from split wood strand(S) and particle(P) of (Cryptomeria japonica D. Don), which changed the layer construction and the ratio of S/P. The influence of layer construction on board properties was determined, focusing on the number and alignment of the S layers. The effect of weight ratio of S/P (3:7, 1:1, 7:3) on mechanical properties was also discussed on seven layered panel. Mechanical properties were determined from static bending tests to give parallel and perpendicular modulus of rupture (MOR) and modulus of elasticity (MOE), and the internal bond (IB) strength. In general, the surface strand layers contributed to the MOR and MOE. The parallel MOR and MOE values were the largest for the single layered S panel (only Slayers: S1), but the perpendicular MOR and MOE was the smallest. Perpendicular MOR and MOE were the largest for seven layered composite that had two cross oriented strand layers (SPSPSPS: SP7). Specimens retained more than half of their MOE and MOR after two hours in boiling water and one hour soaking. IB was the largest for the panel having only P layers, however, differences in IB strength were not identified among the other multi-layered composite panels thus the effect of layer construction on IB strength was small. Thickness swelling (TS) and surface roughness were smaller for the composite having P layers on the surface than for those having S layers. The addition of strands did not enhance the mechanical properties (MOR, MOE, IB). TS values for the panels, with which the S/P ratio was over than 1:1, was the similar to the value for the single layered S panels.