• The KSFM Journal of Fluid Machinery
• /
• v.17 no.6
• /
• pp.69-73
• /
• 2014

To predict flow fields and chemical agent dispersion in urban area, wind tunnel experiments was performed. The agent was adopted MS (methyl salicylate) because the real chemical agent is unsafe. The exact concentration of methyl salicylate was generated by the commercial gas generator (STI-2500) and three different obstacle shapes were applied (i.e., rectangular, cylinder and pyramid). The concentration was measured with the qualified ion mobility sensor and gas chromatography. The data necessary for virtual test method of the real chemical agent were obtained.

• Journal of the Optical Society of Korea
• /
• v.16 no.2
• /
• pp.170-173
• /
• 2012

We present a method that enables dual threshold voltages in a vertical alignment liquid crystal device, through which the gamma shift can be reduced with no subsequent decrease in the contrast ratio. By forming polymer layers, the threshold voltage shift is accomplished through the utilization of the voltage drop effect. We expect that the proposed method can be applied to the conventional 4-domain mode in order to achieve an 8-domain mode without the need for complex driving schemes.

• The Journal of Internal Korean Medicine
• /
• v.25 no.1
• /
• pp.92-105
• /
• 2004

In order to evaluate the anti-tumor and synergic effect of BoJungIkKeeHapDaeChilKi-Tang on doxorubicin, the inhibitory concentration(IC), IC50 and IC90 of single use of doxorubicin and BoJungIkKeeHapDaeChilKi-Tang with their concomitant treatment against MKN-45(Human stomach carcinoma) was observed using MTT(Microculture Tetrazolium test) assay. In addition, their anti-tumor effects were also observed in the xenograft nude mice models agianst MKN-45 cell lines. BoJungIkKeeHapDaeChilKi-Tang has only mimic direct anti-tumor effect against to MKN-45 cell lines but they were decreased general depressed signs induced by implantation of tumor cell lines and increased the total WBC and lymphocyte numbers. So, it is considered or expected that BoJungIkKeeHapDaeChilKi-Tang extracts were reduced by the critical toxicity of doxorubicin and shows favorable synergic effect with doxorubicin and BoJungIkKeeHapDaeChilKi-Tang extracts.

• Pediatric Infection and Vaccine
• /
• v.27 no.1
• /
• pp.24-34
• /
• 2020

The Korean Society of Pediatric Infectious Diseases and the Korea Centers for Disease Control and Prevention issued the guidelines about coronavirus disease 2019 (COVID-19) for children and adolescents. Case definitions and management of COVID-19 in neonates, infants, children and adolescents are presented in this guideline. In addition, guidelines for caregiver management are also provided. In this review, we introduce the contents of the current guidelines for COVID-19 in children and adolescents in Korea.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2003.11c
• /
• pp.1637-1640
• /
• 2003

기존 정보체계는 사용자 요구와 새로운 기술의 도입으로 급속하게 발전하고 있으며, 정보시스템의 재사용성과 확장성, 유지 보수를 위하여 EJB, COM+, CCM 모델 같은 컴포넌트 기술과 컴포넌트 기반 개발 방법론인 CBD 방법론이 연구되고 있다. 또한 이러한 컴포넌트 기술을 이용한 기존 정보시스템의 변환 연구도 같이 이루어지고 있으며, 대표적인 연구로는 미 국방성의 FACELIFT 프로젝트와 카네기멜론 대학 프로젝트 등이 있다. 반면에 현재의 국내 군 정보시스템은 다양한 플랫폼 및 언어 그리고 업무 지향적인 개발로 인해 자원이 낭비되고, 유지보수가 어려운 문제점이 있다. 따라서 본 논문에서는 이미 개발되어 운용중인 군 정보시스템을 분석하여 컴포넌트 기술에 의한 웹 환경으로 변환하는 절차를 제시하고, 클라이언트/서버 구조로 운용중인 군인연금서비스시스템의 일부분을 컴포넌트 기술을 이용하여 웹 환경으로 변환하였다.

• Proceedings of the KIEE Conference
• /
• 2008.04c
• /
• pp.187-189
• /
• 2008

The HEMU-400X(High-speed Electric Multiple Unit 400km/h experiment) project starts last fear. It is required to control and balance the systems engineering activities throughout the project life cycle for a successful completion of the project. This paper proposes the systems engineering management plan for the HEMU-400X project.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1998.10c
• /
• pp.139-144
• /
• 1998

This study is intended to devolop the self waterproof agents for high performance concrete by analyzing the properties of fresh and hardened mortar with various addition ratios of the inorganic admixture and zinc stearate. As the results of the test, the flow and air content increase with the addition of expansive additives. When the replacement rate of silica fume increases, the flow decreases for the increased viscidity. And the flow and sir content decrease with the addition of zinc stearate. At hardened state, the compressive strength, tensile strength and flexual strength decrease with the addition of expansive additives and zinc stearate. With the increase of silica fume's replacement, they show a little decrease at early age and then increase gradually. Also, absorption and permeability show a steep decrease when zinc stearate is added, and a slack decrease with the replacement of silica fume.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2004.05a
• /
• pp.520-523
• /
• 2004

The finite element method(FEM) models were developed for the reinforced concrete flexural walls and analysed under constant axial and monotonic lateral load using ABAQUS. The major objective of the present study is to determine if the ABAQUS finite element program can be used to accurately model the post-cracked mode of failure in plastic regions of walls, and, if so, to develop practical failure criteria in the plastic range of the material response. The research comprises constitutive models to represent behavior of the materials that compose a wall on the basis of experimental data, development of techniques that are appropriate for analysis of reinforced concrete structures, verification, and calibration of the global model for reinforced concrete walls of increasing complexity. Results from the analyses of these FEM models offers significant insight into the flexural behavior of benchmark data.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2008.11a
• /
• pp.93-96
• /
• 2008

This research performed strength improvement analysis after evaluating strength characteristics by estimated temperatures to evaluate the real time strength performance of 50 to 80 MPa high performance concrete equipped with heat resistance, and the results are as follows. The lesser W/B and the lesser target slump flow value difference, compression strength was shown to increase, and the more curing temperature becomes, the strength increased accordingly. According to the correlation review result of strength improvement analysis by estimated temperature change performed using logistic analysis model, the compression strength value predicted with logistic curve expression and the compression strength value measured in experiment were shown to have similar correlation, and the strength improvement analysis value by logistic model was shown to be estimated good when W/B is high.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2014.05a
• /
• pp.138-139
• /
• 2014

In this study, conventional aggregate obtained from a ready mixed concrete factory and the aggregate with a modified grading produced in lab. condition were prepared. Results showed that a good grading of aggregate the ratio of 5~13 mm and 13~25 mm is 20~40 % produced in the lab. condition significantly improved the slump and the compressive strength of the concrete.