• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.2
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• pp.121-125
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• 2010

Carbon Capture and Storage (CCS) technology mitigates the emission amount of carbon dioxide into the atmosphere and can reduce green house effect which causes the climate change. Deep saline aquifer or obsolete oil/gas storage etc. in the marine geological structure are considered as the candidates for the storage. The injection and storage relating technology have been interested in the global society, however the adverse effect caused by leakage from the system failure. Even the safety level of the CCS is very high and there is almost no possibility to leak but, still the risk to marine ecosystem of the high concentrated carbon dioxide exposure is not verified. The present study introduces the system and environmental risk assessment methods. The feature, event and process approach can be a good starting point and we found the some possibility from the fault tree analysis for evaluation. From the FEP analysis, we drove the possible scenario which we need to concentrate on the construction and operation stages.

• Journal of the Korea Safety Management & Science
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• v.17 no.2
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• pp.129-137
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• 2015

This study is in regard to the gas detection system and gas detection method utilizing smart phone. This study includes; 1) the sensor module attached to the smart phone to detect and measure flammable gas or toxic gas; and 2) gas detection APP which is installed inside the smart phone and recognizes the user information and location information automatically by reading RFID tag indicating the user or the location to detect gas through the contact area where RFID and blue tooth reader is installed inside of the above mentioned smart phone, and then measures the combustible gas or toxic gas by operating above mentioned sensor module and obtains the data thus measured, and above mentioned smart phone is characterized by its transmission of the above mentioned user information, location information and measured data which are obtained by above mentioned gas detecting APP to operation server via communication network. With this, reliability for the location detecting gas by the user, the result of the measurement, etc. can be secured. Furthermore, this provides the effect of preventing artificial manipulation at the time of input which is associated with the identification of the user to be measured by utilizing removable sensor module and application or the mistake resulted from wrong input by the user. In addition, by transmitting the measured data from the sensor module carrying out gas detection to operation server, this provides the effect of making it possible to process the data thus collected to a specialized data for combustible gas or toxic gas.

• Nutrition Research and Practice
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• v.2 no.4
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• pp.211-217
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• 2008

This study was purposed to investigate the effect of onion or beet on plasma and liver lipids, erythrocyte Na efflux channels and platelet aggregation in simvastatin (SIM) treated hypercholesterolemic rats. Forty Sprague Dawley rats were divided into four groups and fed 0.5% cholesterol based diets containing 2 mg/kg BW simvastatin or simvastatin with 5% onion or beet powder. Plasma total cholesterol was significantly increased in SIM group compared with the control (p<0.01), and the elevated plasma total cholesterol of SIM group was significantly decreased in SIM-onion and SIM-beet groups (p<0.05). HDL-cholesterol in SIM-beet group was significantly increased compared with other groups (p<0.05). Platelet aggregation in both the maximum and initial slope was significantly decreased in SIM group compared with SIM-onion group (p<0.05). Na-K ATPase was significantly decreased in SIM group compared with the control, SIM-onion and SIM-beet groups (p<0.05). Na passive leak was significantly increased in all groups treated with SIM compared with the control (p<0.05). The total Na efflux was decreased in SIM group and increased in SIM-onion group and the difference between these two groups was significant (p<0.05). There was no difference in intracellular Na among groups. In present study, simvastatin, a HMG CoA reductase inhibitor at dose of 2mg/kg BW/day rather increased plasma total cholesterol in rats, inferring that the action mechanism of simvastatin on cholesterol metabolism differ between rat and human. Onion and beet play favorable roles in cardiovascular system by restoring the reduced Na efflux through Na-K ATPase and Na-K cotransport in SIM treated rats.

• Nuclear Engineering and Technology
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• v.25 no.1
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• pp.51-62
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• 1993

A computational program ［TDET］ of the particle transport equation is developed on radiation shielding problem in two-dimensional cartesian geometry based on the discrete element method. Not like the ordinary discrete ordinates method, the quadrature set of angles is not fixed but steered by the spatially dependent angular fluxes. The angular dependence of the scattering source term in the particle transport equation is described by series expansion in spherical harmonics, and the energy dependence of the particles is considered as well. Three different benchmark tests are made for verification of TDET : For the ray effect analysis on a square absorber with a flat isotropic source, the results of TDET calculation are quite well conformed to those of MORSE-CG calculation while TDET ameliorates the ray effect more effectively than S$_{N}$ calculation. In the analysis of the streaming leakage through a narrow vacuum duct in a shield, TDET shows conspicuous and remarkable results of streaming leakage through the duct as well as MORSE-CG does, and quite better than S$_{N}$ calculation. In a realistic reactor shielding situation which treats in two cases of the isotropic scattering and of linearly anisotropic scattering with two groups of energy, TDET calculations show local ray effect between neighboring meshes compared with S$_{N}$ calculations in which the ray effect extends broadly over several meshes.eshes.

• Journal of the Korean Electrochemical Society
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• v.10 no.4
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• pp.301-305
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• 2007

The performance of polymer electrolyte membrane fuel cell could be decreased due to coolant leaked from connection part. Micro pump was used to put small amount of coolant and investigate the effect on fuel cell. The stoichiometric ratio of hydrogen/air was 1.5/2.0, both side of gas was fully humidified, and current density of $400mA/cm^2$ was used as standard condition in this experiment. Constant current method was used to check performance recovery from coolant effect in 3 cell stack. The performance was recovered when coolant was injected in cathode side. On the other hand, the performance was not recovered when coolant was injected in anode side. Ethylene glycol could be converted to CO in oxidation process and cause poisoning effect on platinum catalyst or be adhered on GDL and cause gas diffusion block effect resulting performance decrease. Water with nitrogen gas was supplied in anode side to check performance recovery. Polarization curve, cyclic voltammetry, electrochemical impedance spectroscopy was used to check performance, and gas chromatography was used to check coolant concentration. Constant current method was not enough in full recovery of performance. However, water injection method was proved good method in full recovery of performance.

• Tuberculosis and Respiratory Diseases
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• v.58 no.3
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• pp.276-284
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• 2005

Backgraound : There have been many reports on the pathogenesis of sepsis-induced acute respiratory distress syndrome(ARDS) but, the precise mechanism has not been elucidated. This study examined the protective effect of an inhibition of platelet activating factor(PAF) remodeling and the adhesion molecule on the oxidative stress of the lungs in rats with an endotoxin induced acute lung injury(ALI). Methods : ALI was induced in Sprague-Dawley rats by instilling an E-coli endotoxin into the trachea. Ketotifen and fucoidan were used respectively to inhibit PAF remodeling and adhesion molecule. The lung leak index, lung myeloperoxidase(MPO) activity, bronchoalveolar lavage(BAL) fluid neutrophil count and lyso PAF acetyltransferase activity(AT), were measured and an ultrastructural study and cytochemical electron microscopy were performed. Results : The lung leak index, lung MPO activity, BAL fluid neutrophil count and lyso PAF AT activity was higher in the endotoxin-treated rats. In addition, severe destruction of the pulmonary architecture and increased hydrogen peroxide production were identified. These changes were reversed by ketotifen. However, fucoidan did not appear to have any protective effects. Conclusion : The inhibition of PAF remodeling appeared to be effective in decreasing the endotoxin-induced ALI. In addition, this effect might be derived from the inhibition of neutrophilic oxidative stress. However, the inhibition of the adhesion molecules by fucoidan appeared to be ineffective in decreasing the endotoxin-induced ALI.

• Journal of Microbiology
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• v.39 no.1
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• pp.62-66
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• 2001

Unlike eukaryotic efflux pumps energized by ATPase bacterial efflux pumps are energized by the proton motive force. That is the reason why CCCP, an inhibitor of proton motive forcer is widely used to study the bacterial efflux pump. In many cases, efflux systems have been observed only in quinolone-resistant bacteria. Most of the quinolone-susceptible strains have been found to maintain little efflux pump. However some susceptible bacteria skewed the increased intracellular quinolone concentration only at a low concentration (0.01 or 0.1 mM) but net at a high concentration (1 mM) of CCCP. If bacterial cells were killed at high concentrations of CCCP and lost the integrity of their membranes, the intracellular quinolone would leak out from cells with no efflux system. The efflux pump system in the quinolone-susceptible strains could net be detected at the same concentration used for resistant bacteria. To test this hypothesist the intracellular quinolone concentration in the quinolone-susceptible and -resistant strains of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus was assayed at various concentrations of CCCP. Since the effect of CCCP is very rapid, the survival of bacteria was observed by assaying the DNA synthesis in 5 min. In the case of E. coli, but not P. aeruginosa or S. aureus, the quinolone susceptible strain was more susceptible to CCCP than the quinolone resistant ones, especially when the incubation with CCCP was extended. Decrease of the intracellular quinolone concentration resulted in a false result-no or weak efflux system in the quinolone susceptible strains. Results suggested that the concentration of CCCP should be optimized in order to detect the efflux system in the quinolone susceptible strains of E. coli.

• Transactions of the KSME C: Technology and Education
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• v.3 no.4
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• pp.291-297
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• 2015

As promising future energy source, hydrogen has been drawing much attention; however, it is easily leaked from the small gap in any storage container due to its find molecule size. In this study, Laser induced breakdown spectroscopy(LIBS) was used for hydrogen leak detection, and feasibility of the scheme was evaluated based on different way for plasma generation. Laser power of 295 mW was required for generating plasma on metal surface to measure hydrogen atomic emission while approximately 2.5 times higher laser power was needed for plasma formation directly in the hydrogen gas stream. It was shown that peak to base ratio increased linearly with increasing the concentration of hydrogen. It can be concluded that LIBS is a viable technique for hydrogen sensing when the concentration of hydrogen is less than 5%.

• Journal of Korean Neurosurgical Society
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• v.52 no.3
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• pp.228-233
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• 2012

Objective : Chronic neck or back pain can be managed with various procedures. Although these procedures are usually well-tolerated, a variety of side effects have been reported. In this study we reviewed cases of unexpected temporary adverse events after blocks and suggest possible causes. Methods : We reviewed the records of patients treated with spinal pain blocks between December 2009 and January 2011. The types of blocks performed were medial branch blocks, interlaminar epidural blocks and transforaminal epidural blocks. During the first eight months of the study period (Group A), 2% mepivacaine HCL and triamcinolone was used, and during the last six months of the study period (Group B), mepivacaine was diluted to 1% with normal saline. Results : There were 704 procedures in 613 patients. Ten patients had 12 transient neurologic events. Nine patients were in Group A and one was in Group B. Transient complications occurred in four patients after cervical block and in eight patients after lumbar block. Side effects of lumbar spine blocks were associated with the concentration of mepivacaine (p<0.05). The likely causes were a high concentration of mepivacaine in five patients, inadvertent vascular injection in three patients, intrathecal leak of local anesthetics in one, and underlying conversion disorder in one. Conclusion : Spinal pain blocks are a good option for relieving pain, but clinicians should always keep in mind the potential for development of inevitable complications. Careful history-taking, appropriate selection of the anesthetics, and using real-time fluoroscopy could help reduce the occurrence of adverse events.

• Journal of the Korean Society for information Management
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• v.32 no.1
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• pp.63-84
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• 2015

Library users must provide their personal information to libraries. This study surveyed these library users' perception of privacy and the effect of the education after providing library user privacy education. As a result, first, it was found that after education, users were more interested in their privacy, rated the problem of library user privacy as more severe, and rated library user data collection as more likely to be considered privacy invasion. Second, we investigated users' perception of how much user service records being collected in libraries violate users' privacy, which showed a great perception change in 25 questions after the education. Third, in the survey about library and librarians' efforts for protecting library user privacy, it was found that all 15 questions were rated as significantly more important after education. Fourth, library users have recognized that is necessary to process and handle the library record and are more sympathetic to the need for this procedure. Fifth, library users felt the possibility of a library record leak was a very serious threat.