• Journal of the Korean Institute of Gas
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• v.19 no.3
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• pp.49-53
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• 2015

The purpose of this paper is to study and analyze the failure examples for fire by friction on clutch, manual transmission and tire system in a car. In the first example, the driver took the pedal with foot to act the clutch. But the clutch disk did not return from flywheel by leakage of clutch hydraulic line. The heat was produced between clutch disk and flywheel by surface contacting. As a result, it was produced the fire by oil sludge sticked with transmission. In the second example, the transmission system was operated to transfer power of engine by contacting with gear and gear. But, as if the oil of transmission was caused the oil insufficiency because of leaking by crack of transmission case, it found the fact that was produced the fire by deposit material on transmission case. In the third example, when the car's driver continuously pushed an accelerator pedal for escaping from dry pit, the tire took the heat by the friction force between tire and surface of road. As a result, it became the direct cause for the fire. Therefore the driver must manage not to produce the fire with friction parts by heating during running.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.9 no.3
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• pp.102-106
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• 2010

Recently process industries from oil and gas procedures and mining companies to manufactures of chemicals, foods, and beverages has been exploring the USN (Ubiquitous Sensor Networks) technology to improve safety of production processes. However, to apply the USN technology in the large-scale plant industry, reliability and security issues are not fully addressed yet, and the absence of the industrial sensor networking standard causes a compatibility problem with legacy equipment and systems. Although this situation, process industry such as energy plants are looking for the secure wireless plant solution to provide detailed, accurate safety monitoring from previously hard-reach, unaccordable area. In this paper, SPSF (Smart Plant Safety Framework based on Reliable-Secure USN) is suggested to fulfill the requirements of high-risk industrial environments for highly secure, reliable data collection and plant monitoring that is resistant to interference. The SPSF consists of three main layers: 1) Smart Safety Sensing Layer, 2) Smart Safety Network Layers, 3) Plant Network System Layer.

• Journal of Ocean Engineering and Technology
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• v.24 no.5
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• pp.1-7
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• 2010

Offshore, sub-sea pipelines that transport oil and gas experience thermal expansion induced by the temperature of the transported medium during operation. The expansion of the pipeline can induce overload and cause damage to offshore platforms or sub-sea structures that are connected to the pipelines. To mitigate and prevent these incidents, expansion spools are installed between offshore, sub-sea pipelines and risers on the platform. This paper presents the results of the study and development of a simplified design method for expansion spools, using the slope deflection method for the purpose of preliminary design or front-end engineering and design (FEED).

• The Korea Journal of Herbology
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• v.36 no.2
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• pp.1-9
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• 2021

Objectives : Gossypium arboreum (cotton) is traditionally used to treat various health disorders. However, anti-amnesic effect of G. arboreum has not been reported. The objective of this study was to investigate in-vivo the anti-amnesic effects along with in vitro antioxidant and acetylcholinesterase (AChE) inhibition potential in G. arboreum seed essential oil. Methods : The essential oil of G. arboreum obtained by solid phase microextraction (SPME) techniques were identified by gas chromatography-mass spectroscopy (GC-MS). 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay were performed to determine the antioxidant activity at various concentrations (312.5, 625, 1250, 2500, 5000, 10000 ㎍/㎖. Y-maze, passive avoidance and Morris water maze tests were carried out to evaluate improved effect on scopolamine (1 mg/kg)-induced memory dysfunction at the dose level of 50, 100 and 200 mg/kg. Donepezil (5 mg/kg) was used as a positive drug control. We performed acetylcholinesterase (AChE) activity assay in ex vivo. Results : Five volatile compounds were identified in G. arboreum. The assays of DPPH and ABTS revealed that G. arboreum increased antioxidant activity in a dose-dependent manner. G. arboreum ameliorated the percent of spontaneous alternation in the Y-maze test, shortened step-through latency in the passive avoidance test, and increased swimming time in the target zone in the Morris water maze test. In addition, G. arboreum inhibited the AChE activity. Conclusions : Based on these findings, G. arboreum may aid in the prevention and treatment of learning and memory-deficit disorders through antioxidant and AChE inhibitory activities.

• Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.159-165
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• 2014

In this study, Krill Eupausia superba oil was extracted using different solvents and supercritical carbon dioxide (SC-$CO_2$). During SC-$CO_2$ extraction, the pressure was set at 40 MPa and temperatures ranged from $40^{\circ}C$ to $55^{\circ}C$. We examined the differences in volatile compounds and safety profiles among extraction methods. Volatile compounds were determined using the thermal desorption system integrated with gas chromatography-mass spectrometry (GC-MS). Heavy metal content was analyzed by inductively coupled plasma mass spectrometry (ICP-MS). According to our results 10 volatile compounds were identified in krill sample. After SC-$CO_2$ extraction of oil, the concentrations of volatile compounds decreased, but increased after solvent extraction. In krill, heavy metal concentrations remained within the permissible limit. Moreover, Zn and Fe which have health benefits were detected at high concentrations. During a 90 days storage period at different temperatures, microbial activity was found to be lowest in SC-$CO_2$ extracted residues. Thus, the quality of krill oil and the residues obtained using SC-$CO_2$ extraction was higher and the oil was safer than those obtained using conventional solvent extraction. These results can be applied to the food industry to maintain high quality krill products.

• Journal of the Korean Society for Heat Treatment
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• v.12 no.2
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• pp.136-144
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• 1999

The study on the wear characteristics of compound layers formed during gaseous nitrocarburising in the medium carbon boron steels and the plain carbon steel has been carried out by using a pin-on-disc type wear test machine under the oil lubricating condition at room temperature and by varying applied loads, sliding speeds and wear distances. Values of friction coefficient measured at the sliding speed of 0.4m/sec under the oil lubricating condition have been shown to decrease considerably with increasing applied load and become gradually a constant value as load is increased to a higher value, showing that the transition load for friction coefficient appears at an applied load of 247.2N. The length and volume wear rates of compound layer have been revealed to relatively constantly increase, also showing that the wear life per unit thickness of compound layer turns out to be superior as porous layer has a denser and thinner appearance. As the sliding speed increases during wear test performed by varying sliding speed at a load of 63.2N under the oil lubricating condition for medium carbon boron steel nitrocarburised in gas atmosphere, the wear rate has been found to increase, the friction coefficient to decrease and the wear life per unit thickness of compound layer to decrease considerably.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.3
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• pp.435-451
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• 2015

Evaluation of the performance of aging structures is essential in the oil and gas industry, where the inaccurate prediction of structural performance can have significantly hazardous consequences. The effects of structure failure due to the significant reduction in wall thickness, which determines the burst strength, make it very complicated for pipeline operators to maintain pipeline serviceability. In other words, the serviceability of gas pipelines and elbows needs to be predicted and assessed to ensure that the burst or collapse strength capacities of the structures remain less than the maximum allowable operation pressure. In this study, several positions of the corrosion in a subsea elbow made of API X42 steel were evaluated using both design formulas and numerical analysis. The most hazardous corrosion position of the aging elbow was then determined to assess its serviceability. The results of this study are applicable to the operational and elbow serviceability needs of subsea pipelines and can help predict more accurate replacement or repair times.

• Journal of Life Science
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• v.29 no.2
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• pp.223-230
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• 2019

Ozone is a gaseous molecule able to kill microorganisms, such as yeast, fungi, bacteria, and protozoa. However, ozone gas is unstable and cannot be used easily. In order to utilize ozone properly and efficiently, plant oil can be employed. Ozone reacts with C-C double bonds of fatty acids, converting to ozonized oil. In this reaction, ozonide is produced within fatty acids and the resulting ozonized oil has various biological functions. In this study, we showed that ozonized oil has antimicrobial activity against fungi and bacteria. To test the antimicrobial activity of ozonized oil, we produced ozonized olive oil. Ozonized olive oil was applied to Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. Antimicrobial activity was assayed using the disk diffusion method following the National Committee for Clinical Laboratory Standards. Minimal inhibitory concentrations (MIC) were 0.25 mg for S. aureus, 0.5 mg for S. epidermidis, 3.0 mg for P. aeruginosa, and 1.0 mg for E. coli. Gram positive bacteria were more susceptible than Gram negative bacteria. We compared growth inhibition zones against S. aureus and MRSA, showing that the ozonized olive oil was more effective on MRSA than S. aureus. Furthermore, the ozonized olive oil killed C. albicans within an hour. These data suggested that ozonized olive oil could be an alternative drug for MRSA infection and could be utilized as a potent antimicrobial and antifungal substance.

• Applied Biological Chemistry
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• v.27 no.4
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• pp.278-284
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• 1984

The triglyceride compositions of peach kernel and apricot kernel oil have been investigated by a combination of high performance liquid chromatography (HPLC) and gas liquid chromatography(GLC). The triglycerides of peach kernel and apricot kernel oil were first separated by thin layer chromatography(TLC), and fractionated on the basis of their partition number(PN) by HPLC on a C-18 ${\mu}-Bondapak$ column with methanol-chloroform solvent mixture. Each of these fractionated groups was purely collected and analyzed by GLC according to acyl carbon number(CN) of triglyceride. Also the fatty acid compositions of these triglycerides were determined by GLC. From the consecutive analyses of these three chromatography techniques, the possible triglyceride compositions of peach kernel and apricot kernel oil were combinated into fifteen and thirteen kinds of triglycerides, respectively. The major triglycerides of peach ternel oil were those of $(3{\times}C_{18:1}\;30.9%)$, $(2{\times}C_{18:1},\;C_{18:2},\;21.2%)$, $(C_{18:1},\;2{\times}C_{18:2}\;10.6%)$, $(3{\times}C_{18:2}\;3.8%)$, $(C_{18:0},\;2{\times}C_{18:1},\;1.8%)$, $(C_{16:0},\;C_{18:1},\;C_{18:2},\;1.5%)$, $(C_{18:0},\;C_{18:1},\;C_{18:2},\;1.1%)$ and those of apricot kernel oil were $(3{\times}C_{18:1},\;39.5%)$, $(2{\times}C_{18:1},\;C_{18:2},\;24.5%)$, $(C_{18:0},\;2{\times}C_{18:2},\;14.2%)$, $(3{\times}C_{18:2},\;2.0%)$.

• Journal of the Korean Society of Systems Engineering
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• v.11 no.1
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• pp.81-93
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• 2015

Steam Reforming H2 Generation (SRH2G) System is a chemical process to produce hydrogen through steam reforming of hydrocarbon. Largely speaking, there are two types of materials for the SRH2G: 1) Oil and coal, and 2)Natural Gas such as shale gas. From the perspective of cost, quality (purity), and environmental burden (pollution), the latter is much more desirable than the former. For this reason, research on SRH2G using natural gas is actively carried out, and implemented and operated in the various industry. In this paper, we develop a natural gas based SRH2G system via systems engineering approach. Specifically, we first derived stakeholder requirements, followed by systems requirements and finally system architecture via a tailored SE process for plant (called Plant Systems Engineering (PSE) process) based on ISO/IEC 15288. The developed method was applied to iron and steel plant as a case study. Through the case study, by the SE approach, we were convinced that a successful system satisfying stakeholders' requirements within the given constraints can be developed, verified and validated.