• Korean Chemical Engineering Research
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• v.62 no.1
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• pp.70-79
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• 2024

Raman analyzer is an analytical technique that utilizes the "Raman effect", which occurs when light is scattered by the inherent vibrations of molecules. It is used for molecular identification and composition analysis. In the natural gas industry, it is widely used in bunkering and tank lorry fields in addition to LNG export and import terminals. In this study, a LNG-specific Raman analyzer was installed and operated under actual field conditions to analyze the composition and principal properties (calorific value, reference density, etc.) of LNG. The measured LNG composition and calorific value were compared with those obtained by conventional gas chromatograph that are currently in operation and validated. The test results showed that the Raman analyzer provided rapid and stable measurements of LNG composition and calorific value. When comparing the calorific value, which serves as the basis for LNG transactions, with the results from conventional gas chromatograph, the Raman analyzer met the acceptable error criteria. Furthermore, the measurement results obtained in this study satisfied the accuracy criteria of relevant international standards (ASTM D7940-14) and demonstrated similar outcomes compared to large-scale international demonstration cases.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.106-111
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• 2008

Advanced concrete technology, which is the main construction technology of skyscraper, is dealt with in this paper. Advanced concrete technologies are classified into several types such as super high strength concrete(SHSC), low heat concrete(LHC), fire resistant concrete(FRC) and blast resistant concrete(BRC). The necessity, principal and application examples of advanced concrete technology are described respectively. In the last part of the paper, the introduction of HYUNDAI E&C's technology of Advanced concrete and future research trend are described.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.341-344
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• 1999

In the case of the offshore concrete structures like the anchorage block of a suspension bridge of Kwangan Grand Road, there is a need of the concrete which has low heat of hydration and good resistance for sea-water attack. In this study, the blended super low heat cement which satisfies that requirement was developed and several tests were carried out. The concrete using the blended super low heat cement showed lower adiabatic temperature rise than 3$0^{\circ}C$ and good early strength. Also, its passed charge(coulomb) to resist chloride ion penetration was very low.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.1175-1180
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• 2000

Recently, the crack of concrete induced by the heat of hydration of cement is a serious problem for more greater, special and higher strength of concrete structures. The increasing concrete's temperature is mainly caused by the heat of hydration of cement and so, to control the thermal stress of concrete structure is desirable to use low heater material of hydration. There are many methods to diminish the increasing of concrete temperature such as using of low heat cement, addition of fly-ash, application of pre-cooling, etc., and in this study, we evaluate the heating and mechanical properties of ultra low heat mass concrete using Low Heat Portland(KS Type IV) cement with 30% of limestone powder. The results of this study will be applied to side wall and bottom of No. 15 and 16 of underground LNG tank in Inchon.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.569-572
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• 2000

This paper presents the optimized fabrication and thermal characteristics of micro-heaters for thermal MEMS applications using a SDB SOI substrate. The micro-heater is based on a thermal measurement principle and contains for thermal isolation regions a 10$\mu\textrm{m}$ thick silicon membrane with oxide-filled trenches in the SOI membrane rim. The micro-heater was fabricated with Pt-RTD(Resistance Thermometer Device)on the same substrate by using MgO as medium layer. The thermal characteristics of the micro-heater with the SOI membrane is 280$^{\circ}C$ at input Power 0.9 W; for the SOI membrane with 10 trenches, it is 580$^{\circ}C$ due to reduction of the external thermal loss. Therefore, the micro-heater with trenches in SOI membrane rim provides a powerful and versatile alternative technology for improving the performance of micro thermal sensors and actuators.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.3
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• pp.228-233
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• 2001

This paper presents the optimized design, fabrication and thermal characteristics of micro-heaters for thermal MEMS (micro elelctro mechanical system) applications usign SOI (Si-on-insulator) and trench structures. The micro-heater is based on a thermal measurement principle and contains for thermal isolation regions a 10㎛ thick Si membrane with oxide-filled trenches in the SOI membrane rim. The micro-heater was fabricated with Pt-RTD (resistance thermometer device) on the same substrate by suing MgO as medium layer. The thermal characteristics of the micro-heater wit the SOI membrane is 280$\^{C}$ at input power 0.9W; for the SOI membrane with 10 trenches, it is 580$\^{C}$ due to reduction of the external thermal loss. Therefore, the micro-heater with trenches in SOI membrane rim provides a powerful and versatile alternative technology for improving the performance of micro-thermal sensors and actuators.

• Pediatric Infection and Vaccine
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• v.28 no.2
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• pp.92-100
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• 2021

Purpose: Rapid detection of etiologic organisms is crucial for initiating appropriate therapy in patients with central nervous system (CNS) infection. This study aimed to evaluate the diagnostic value of the BioFire^® Meningitis/Encephalitis (ME) panel in detecting etiologic organisms in cerebrospinal fluid (CSF) samples from febrile infants. Methods: CSF samples from infants aged <90 days who were evaluated for fever were collected between January 2016 and July 2019 at the Seoul National University Children's Hospital. We performed BioFire^® ME panel testing of CSF samples that had been used for CSF analysis and conventional tests (bacterial culture, Xpert^® enterovirus assay, and herpes simplex virus-1 and -2 polymerase chain reaction) and stored at -70℃ until further use. Results: In total, 72 (24 pathogen-identified and 48 pathogen-unidentified) CSF samples were included. Using BioFire^® ME panel testing, 41 (85.4%) of the 48 pathogen-unidentified CSF samples yielded negative results and 22 (91.7%) of the 24 pathogen-identified CSF samples yielded the same results (enterovirus in 19, Streptococcus agalactiae in 2, and Streptococcus pneumoniae in 1) as those obtained using the conventional tests, thereby resulting in an overall agreement of 87.5% (63/72). Six of the 7 pathogen-unidentified samples were positive for human parechovirus (HPeV) via BioFire^® ME panel testing. Conclusions: Compared with the currently available etiologic tests for CNS infection, BioFire^® ME panel testing demonstrated a high agreement score for pathogen-identified samples and enabled HPeV detection in young infants. The clinical utility and cost-effectiveness of BioFire^® ME panel testing in children must be evaluated for its wider application.