• Safety and Health at Work
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• v.1 no.2
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• pp.175-182
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• 2010

Objectives: This study examined how ethanolamines (EAs) with the same functional alcohol group ($HOCH_2CH_2$), such as mono-EA (MEA), di-EA (DEA), and tri-EA (TEA), in water-based metalworking fluids (wbMWFs) are vaporized, condensed, and transformed by heat generated during metalworking. Methods: Two types of experimental apparatus were manufactured to achieve these objectives. Results: Vaporization tests using a water bath showed that the vaporization rate increased markedly from $0.19\;mg/m^2{\cdot}min$ at $23.5^{\circ}C$ to $8.04\;mg/m^2{\cdot}min$ at $60^{\circ}C$. Chamber tests with a heat bulb revealed that "spiked" MEA was fully recovered, while only 13.32% of DEA and no TEA were recovered. Interestingly, non-spiked types of EAs were detected, indicating that heat could convert EAs with more alcohol groups (TEA or DEA) into other EAs with fewer group(s) (DEA or MEA). The EA composition in fresh fluid was 4% DEA, 66% TEA, and 30% MEA, and in used fluids (n = 5) was 12.4% DEA, 68% TEA, and 23% MEA. Conversion from TEA into DEA may therefore contribute to the DEA increment. Airborne TEA was not detected in 13 samples taken from the central coolant system and near a conveyor belt where no machining work was performed. The DEA concentration was $0.45\;mg/m^3$ in the only two samples from those locations. In contrast, airborne MEA was found in all samples (n = 53) regardless of the operation type. Conclusion: MEAs easily evaporated even when MWFs were applied, cleaned, refilled, and when they were in fluid storage tanks without any metalworking being performed. The conversion of TEA to DEA and MEA was found in the machining operations.

• Toxicological Research
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• v.32 no.4
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• pp.337-343
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• 2016

We determined the toxicity of mixtures of ethyl acetate (EA), isopropyl alcohol (IPA), methyl ethyl ketone (MEK), toluene (TOL) and xylene (XYL) with half-maximal effective concentration ($EC_{50}$) values obtained using human hepatocytes cells. According to these data, quantitative property-activity relationships (QPAR) models were successfully proposed to predict the toxicity of mixtures by multiple linear regressions (MLR). The leave-one-out cross validation method was used to find the best subsets of descriptors in the learning methods. Significant differences in physico-chemical properties such as boiling point (BP), specific gravity (SG), Reid vapor pressure (rVP) and flash point (FP) were observed between the single substances and the mixtures. The $EC_{50}$ of the mixture of EA and IPA was significantly lower than that of contained TOL and XYL. The mixture toxicity was related to the mixing ratio of MEK, TOL and XYL (MLR equation $EC_{50}=3.3081-2.5018{\times}TOL-3.2595{\times}XYL-12.6596{\times}MEK{\times}XYL$), as well as to BP, SG, VP and FP (MLR equation $EC_{50}=1.3424+6.2250{\times}FP-7.1198{\times}SG{\times}FP-0.03013{\times}rVP{\times}FP$). These results suggest that QPAR-based models could accurately predict the toxicity of polar and nonpolar mixtures used in rotogravure printing industries.

• Proceedings of the Korean Information Science Society Conference
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• 2008.06b
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• pp.91-95
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• 2008

2005년 MND-AF v1.0의 제정으로 시작된 국방 아키텍처 활동은 2007년 범 정부 아키텍처 프레임워크와의 산출물 연계를 위한 v1.2 발표와 함께 새로운 전기를 맞고 있다. 본 논문에서는 국방 아키텍처 활동 소개와 국방 아키텍처 변화에 따른 국방기술품질원의 자체 아키텍팅 활동 정리 그리고 v1.2의 도입과 함께 최근 관심 사항이 되고 있는 ITA/EA 툴의 제품 동향과 도입 사업 추진 시의 평가기준 등을 제시한다.

• Journal of Pharmaceutical Investigation
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• v.24 no.4
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• pp.273-279
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• 1994

The stability of three oximes, Hl-6 [(4-carbamoyl-2'[(hydroxyimino)-methyl]- 1,1'-oxydimethylenedi-(pyridinium chloride)], Hl-CN [(4 cyano-2'-[(hydroxyimino)-methyl] -1,1'-oxydimethylene-di-(pyridinium chloride)], and 2-PAM [pralidoxime chloride] in aqueous solutions was evaluated by HPLC assay. The rate of degradation is dependent on the pH as well as the temperature at which the solution is stored. The optimum pH for the stability of these oximes was pH 2 to 3. The degradation rate constant for 2-PAM ($k\;at\;70^{\circ}C$, $2.07{\times}10^{-4}/hr;\;E_a\;value$, 27.2 kcal/mol) was smaller than those for bis-pyridiniumoximes, Hl-6 ($k\;at\;70^{\circ}C$, $3.38{\times}10^{-3}/hr$) and Hl-CN ($k\;at\;70^{\circ}C$, $8.66{\times}10^{-3}/hr;\;Ea\;value$, 20.7 kcal/mol). In mechanistic analyses, it was found that Hl-CN was decomposed through not only the hydrolysis of nitrile group but also the cleavage of methylene ether bridge, in contrast to Hl-6 which was degraded mainly through the cleavage of methylene ether bridge.

• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.2
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• pp.215-223
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• 2019

A high temperature adhesive development which is crosslinked in low temperature is necessary for aerospace application because of thermal expansion mismatches of various substrates. For this purpose, we have designed and fabricated several formulations with high temperature epoxy resins, crosslinkers and additives considering various working conditions and high service temperature. As a result, some formulations showed higher adhesive strengths than Hysol EA 9394/C2 which is widely used for aerospace applications. We also have studied and summarized the mechanical properties of the best development adhesive in both room and high temperatures.

• Journal of Information Technology and Architecture
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• v.9 no.2
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• pp.187-197
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• 2012

The investment on informatization has caused the increase in complexity of IT resources as well as inefficiency of Information system management and redundant investment. Thus, the idea of EA (Enterprise Architecture) was developed in order to manage the IT resources efficiently but the systematical guideline was insufficiently provided in data area.. Because of this, it is necessary to make full use of DRM (Data Reference Model) so we can enhance the sharing and reuse of data between several institutions in public sector by extracting and managing data behind processes. In this study, we recognize the necessity of improvement on data classification which is highly utilized and present the direction for the data classification rethesis.

• Journal of Digital Convergence
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• v.9 no.6
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• pp.355-368
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• 2011

For an effective warfare under the condition of NCW, the sharing of data between systems must be essential. Thus, the standardization and the integration of data which is considered as the MND-EA improvement and the Megacenter is important. The purpose of this research is to investigate the factors that affected the BI(Behavioral Intention to USE) by using the TAM(Technology Acceptance Model), That is to introduce the MDM into the national defense field which is an issue in every agency sector for data sharing. Also, based on the implementation architecture of Gartner which applies depending on the business enterprise type, the preferred architecture should be selected considering the national defense environment and the characteristics, and suggest an effective MND-MDM plan by analysing the effects on the BI. The survey was done through 19th September till the 7th of October 2011, by investigating the people in charge of the development and maintenance of the national defense information systems and the SI company's national defense team people who have experienced the development of the national defense information systems.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.352-357
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• 2012

Techniques of thermal analyses such as DSC and TGA have been used in the study of activation energy (Ea) and frequency factor (A) depending on the particle size of RDX and HMX. Activation energy and frequency factor were calculated by Kissinger's method and Vyazovkin's method. As the particle size of RDX increased, TGA showed activation energy increased, but DSC didn't show. However, In case of HMX, as the particle size increased, both of DSC and TGA showed increase in activation energy. Moreover, Vyazovkin's method can obtain activation energy and mechanism according to decomposition of RDX and HMX.

• Journal of Information Technology Services
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• v.5 no.1
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• pp.111-128
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• 2006

It was on the rise importantly to provide the efficient management process of the organization for dealing with the change about information and business management quickly and consistently. It was suggested with the architectural model on information technology to provide it in theoretically. The Federal Government and budget organization of the USA used it on actual business and the terms of EA (Enterprise Architecture) and are raising the efficiency of management. NCA (National Computerization Agency) of Korea published the book - "The Research about establishing ITA (Information Technology Architecture) and appling the standards". After being applied the model on MOGAHA (Ministry of Government Administration and Home Affairs) and MIC(Minisstry of Information and Communication), the concrete case was made. MOMAF (Ministry of Maritime Affairs and Fisheries) drove the leading model. The report ascertained the basic contents of ITA and researched the case of USA, MOGAHA, MIC, and tried to analyze the contents of appling maritime and fisheries area. The report contained the definition of purpose through analyzing environment and establishing the vision and the principles based on them. The report also contained the contents of architecture based on the standard of NCA - "The Government Standard Meta Model version 2.0" - and researched the MOMAF's Reference model using Government Reference model. The report established the investment architecture and the process of information technology asset management. It ascertained the characteristic of maritime & fisheries area and the subject of developing the MOMAF's ITA sustainably.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.2
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• pp.131-138
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• 2015

Energetic monomers with new design concept were synthesized for energetic prepolymers. Novel energetic monomers consisted of ring-opening polymerizable oxirane and a molecular explosive moiety instead of small explosophores as energetic functional groups. According to the design concept, glycidyl dinitroazetidine (GDNAZ) and glycidyl nitroazetidinol(GNAZO) energetic monomers were synthesized, respectively, and characterized by NMR, EA and GC MS. Heat of formation and detonation performance were calculated by theoretical method to evaluate energy performance of these novel energetic monomers. The result revealed that GDANZ and GNAZO possessed high potential as new energetic monomers for synthesizing energetic prepolymers and binders in PBXs.