• Journal of Energy Engineering
• /
• v.23 no.4
• /
• pp.169-175
• /
• 2014

For the safe handling of ethylbenzene, this study was investigated the explosion limits of ethylbenzene in the reference data. And the lower flash points, upper flash points and AITs(auto-ignition temperatures) by ignition delay time were experimented. The lower flash points of ethylbenzene by using Setaflash closed-cup and Pensky-Martens closed-cup testers were experimented $20^{\circ}C$ and $22^{\circ}C$, respectively. The lower flash points ethylbenzene by using Tag and Cleveland open cup testers were experimented $25^{\circ}C$ and $28^{\circ}C$, respectively. Also, this study measured relationship between the AITs and the ignition delay times by using ASTM E659 tester for ethylbnezene. The experimental AIT of ethylbenzene was $430^{\circ}C$. The calculated LEL and UEL by using the measured lower flash point and upper flash point were 0.93 Vol.% and 7.96 Vol.%, respectively.

• Radiation Oncology Journal
• /
• v.5 no.2
• /
• pp.141-148
• /
• 1987

The ultimate goal of radiotherapy is to result in complete local control of tumor while sparing the surrounding normal tissues as much as possible. Since the development of CT in 1970s, patient's anatomical normal tissues and the site and extent of infiltration of tumor were identified almost accurately. In addition, the isodose distribution of delivered radiation to target tumor was shown in each cross-section. In the treatment planning of head and neck cancers, CT-reconstruction provided almost 3-dimensinonal inter-relationship between tumor and normal tissues. The utilization of imaging system of the CT scanner made it possible to illustrate in superposition the patient structure image, the radiation beams, and the isodose distributions. Thus it was possible to deliver radiation enough to control the local disease, and to avoid unnecessary administration of radiation to normal tissue such as spinal cord. CT-reconstructed image in axial, sagittal, and coronal planes suggested 3-dimensional radiotherapy treatment planning be possible and practical instead of conventional 2-dimensional planning at coronal plane.

• Journal of Energy Engineering
• /
• v.28 no.4
• /
• pp.42-47
• /
• 2019

In this study, combustion characteristics were measured by selecting di-n-buthylamine, which is widely used as an emulsifier, insecticide, additive, rubber vulcanization accelerator, corrosion inhibitor, and raw material for dye production. The flash point of the di-n-buthylamine was measured by Setaflash, Pensky-Martens, Tag, and Cleveland testers. And the AIT of the di-n-buthylamine was measured by ASTM 659E. The explosion limits of the di-n-buthylamine was calculated using the measured flash points by Setaflash tester. The flash point of the di-n-buthylamine by using Setaflash and Pensky-Martens closed-cup testers were experimented at 38 ℃ and 43 ℃, respectively. The flash points of the di-n-buthylamine by Tag and Cleveland open cup testers were experimented at 48 ℃. The AIT of the di-n-buthylamine was experimented at 247 ℃. The LEL and UEL calculated by using lower and upper flash points of Setaflash tester were calculated at 0.69 vol% and 7.7 vol%, respectively. The measurement of the flash point measurement and the calculation method of the explosion limit prediction presented in this study can be used to study the fire and explosion characteristics of the other combustible liquids.

• The Journal of the Korean Society for Microbiology
• /
• v.14 no.1
• /
• pp.17-25
• /
• 1979

Bacteriologic diagnosis of enteric infection remains to be an important role of clinical laboratory because of the prevalence of the infection. Often the determination of etiologic agent and its susceptibility to antibiotics are of vital importance for a proper management of the infection. In our previous paper, an analysis of the isolation of enteric pathogens for the years 1969-73 was reported to clarify the status of those years. The present analysis was made based on the data obtained during the years 1974-78, to see if any change of the status was rendered. 1. During the 5-year period, from the cultures of 7,308 stool or rectal specimens 833 patients yielded enteric pathogens: 468 Shigella, 295 Salmonella, 30 Vibrio parahaemolyticus and 40 enteropathogenic Escherichia coli(EPEC). 2. Of the 295 Salmonella, 271 were S. typhi Isolation of 12 S.paratyphi-A, 1 Salmonella group B, 4 group C, 5 group D and 2 group E meant a definite increase of these sero-groups, S. typhi was most frequently isolated in August and in December, and from 30- to 39-year-old patients. 3. Of the 468 Shigella, 10 were subgroup A, 338 subgroup B, 3 subgroup C and 117 subgroup D. Most of the subgroup B belonged to type 1,2, or 3. The proportion of S. sonnei decreased from 31.3% in 1974 to 18.2% in 1978. In foreign patients, S. sonnei remained to be the frequntly isolated species. Shigella isolation was frequent in August and in 2- to 5-year-old patients. 4. V. parahaemolyticus was isolated from 30 and EPEC from 40 patients. 5. Ninty-nine per cent and 99.5% of the S. typhi isolates were susceptible to chloramphenicol and to ampicillin respectively. 92.8% of S sonnei were susceptible to ampicillin. S. flexneri type 2 was notable for their markedely decreased proportion being susceptible to ampicillin: 84.4% in 1974 and 25.6% in 1978.

• The Journal of the Korean Society for Microbiology
• /
• v.14 no.1
• /
• pp.11-15
• /
• 1979

Identification of group A $\beta$-phemolytic streptococci is very important to provide an appropriate preventive measure of possible rheumatic fever and acute glomerulonephritis. For such purpose bacitracin susceptibility of streptococci because of its simplity has been most widely used despite of its occasional faulty results. Recently, a coagglutination technique was advocated using streptococcal group specific antibodies adsorbed to protein A-containing staphylococci. This study was conducted to evaluate the coagglutination technique using reagents prepared by ourselves. The specificity, reproducibility and stability were ascertained and the following results were obtained. 1. The identification by coagglutination technique using our own reagent gave the same results compared with the Lancefield precipitation technique. The result also agreed with the Phadebact grouping. 2. There were no variation in group A and B identification due to lot difference. However, there were a few discrepant results in group C and G identification which was conducted in different days with different lots of our reagent. 3. The stability of our reagents was less satisfactory compared to the commercial product. An effort to improve the stability was considered necessary. 4. For coagglutination, it was found convenient to use supernatant of Todd-Hewitt broth incubated for 24 hours. Both parafin-ringed slide glass and RPR card gave comparable results and the former could be used when the latter is not available.

• 한국태양에너지학회:학술대회논문집
• /
• 2011.04a
• /
• pp.179-184
• /
• 2011

The development of new energy has attracted consideration attention due to the high oil price and environmental problems. In advanced country, they have tried to carry out a long range plan for energy. We need to develop new energy for Low Carbon Green Growth in Korea. The building is 30% among ratio of energy consumption in Korea. And in the past, heating energy was high ratio for energy using at home. But recently, the demand for cooling energy keeps growing due to rising average temperature on the earth and improvement of life quality. In this situation, the energy of lake water and ocean water has studied to utilize in advanced country because of low temperature at underwater. But the study for deep water is still a lot left to do. In this study, we analyzed district cooling system and the present condition. Analyzing the deep lake water cooling system in Toronto, we found an application of district cooling system using deep ocean water. Deep lake water uses heat source for district cooling and water source for city in Toronto. So reducing the initial cost, this city had economic effect. When DLWC was applied at existing building, the heat exchanger was installed instead of cooling tower and refrigerator. And the heat exchanger used to connect main pipe with cool water on city. System using deep ocean water can be applied as a similar way to supply cool water from lake to building.

• Journal of the Korean Institute of Gas
• /
• v.18 no.4
• /
• pp.44-50
• /
• 2014

For the safe handling of aniline, this study was investigated the explosion limits of aniline in the reference data. And the lower flash points, upper flash points and AITs(auto-ignition temperatures) by ignition delay time were experimented. The lower flash point of aniline by using Setaflash and Penski-Martens closed-cup testers were experimented $66^{\circ}C$ and $73^{\circ}C$, respectively. The lower flash point aniline by using Tag and Cleveland open cup testers were experimented $72^{\circ}C$ and $78^{\circ}C$, respectively. Also, this study measured relationship between the AITs and the ignition delay times by using ASTM E659 tester for aniline. The experimental AIT of aniline was $590^{\circ}C$. The calculated LEL and UEL by using the measured low flash point and upper flash point were 1.16 Vol.% and 8.36 Vol.%, respectively.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.65 no.8
• /
• pp.1326-1333
• /
• 2016

It is important to clear the fault and prevent resulting in damage to power system. Although the frequency of generator internal fault is relatively low, it can lead to incalculable damage to power system as well as generator. Especially, loss of field on generator can cause the generator to lose synchronism for a short time if it is not removed promptly. Therefore, it is needed to conduct research on loss of field relay for detecting or clearing the loss of field. However, the setting of the relay may vary in generator operator or engineer, and the relay is not coordinated well with other elements associated with loss of field. In this paper, we address specifically the coordination of positive offset mho loss of field relay which is one of the protection schemes for loss of field. Computer simulations are performed by using ElectroMagnetic Transients Program-Restructured Version (EMTP-RV) based on actual data.

• The Journal of the Korean Society for Microbiology
• /
• v.8 no.1
• /
• pp.27-32
• /
• 1973

Listeria monocytogenes human infection is a relatively rare disease which usually is meningitis in newborn babies. The organism was isolated from blood cultures of a 52 year old female patient with meningitis. It was considered that the underlying disease, i.e. S.L.E., and the steroid therapy which the patient had been receiving played some role for the Listeria infection. The isolate was showing characteristics of L. monocytogenes, i.e. diphtheroid like morphology, motility with four peritrichous flagella, hemolytic small colonies on blood agar, growth in the presence of 7.5% salt and at 4 C, and inducing monocytosis in an experimentally infected rabbit. Serologically the organism was identified as L. monocytogenes 4b. The isolate was showing susceptibility to many antibiotics tested including ampicillin, penicillin and tetracycline which were the recommended drugs of choice for the treatment of Listeriosis. It is the general opinion that Listeriosis is not so rare as literatures are showing. It is considered that some of the isolate of the organism from clinical specimens are mistakenly discarded due to the fact that the organism shows diphtheroid like morphology and that not many laboratories are able to recognize the organism. Literatures are seen which emphasize more careful examination of gram positive bacilli with diphtheroid like morphology especially when they are isolated from blood or from spinal fluid of patient.

• Journal of The Korean Society For Urban Railway
• /
• v.6 no.4
• /
• pp.393-399
• /
• 2018

It is well recognized that residual stresses of the rails, generated from the manufacturing process including roller straightening and heat treatment, play an important role in determining fatigue and fracture properties of the rails. Thus, it has been a challenge to measure the residual stresses accurately. In this work, contour method was employed to evaluate the residual stresses existing in interior of the rails. The cross section perpendicular to the longitudinal direction of the rail was cut at a very slow rate using electric discharge machining (EDM), after which a laser-based flexural measuring instrument enabled us to precisely measure the flection of the cross section. The measured data were converted into the residual stresses using the commercial finite element package, ABAQUS, through a user-defined element (UEL) subroutine, and the residual stresses of the new rails (50N, KR60, UIC60) with three different specifications were compared.