• Title/Summary/Keyword: preliminary test

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A Preliminary Design of Flight Test Conditions for a Sub-scale RBCC Engine using a Sounding Rocket

  • Kim, Hye-Sung;Kim, Kui-Soon;Oh, Se-Jong;Choi, Jeong-Yeol;Yang, Won-Seok
    • International Journal of Aeronautical and Space Sciences
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    • v.16 no.4
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    • pp.529-536
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    • 2015
  • Various R&D programs for rocket-based combined cycle (RBCC) engines have progressed worldwide for the space development and the defense applications. As a way toward indigenous domestic RBCC program, a preliminary design of flight test conditions was studied in this study for a sub-scale RBCC engine using a sounding rocket. Launch and flight profiles were calculated for several booster options and compared with that of HyShot II program. The result shows that the Korea Sounding Rocket-II (KSR-II) is a proper candidate to perform the flight test available in Korea. The recommend flight test conditions with KSR-II are Mach 6.0 with a test vehicle of 230 kg and Mach 7.4 with 50 kg. Present study will soon be followed by a design of sub-scale RBCC for a flight test using a sounding rocket.

Development and Application of Evaluation Tool for Sexuality Education in Elementary School (초등학교 성교육 평가도구 개발 및 적용)

  • Yang Soon-Ok;Jeong Geum-Hee;Kim Shin-Jeong;Lee Que-Young;Baek Sung-Sook
    • Child Health Nursing Research
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    • v.8 no.3
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    • pp.334-343
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    • 2002
  • This study was aimed at primarily to develop a tool to evaluate sexuality education and secondarily to test effectiveness through application of developed evaluation tools in elementary school. The results from this study were summarized below: 1. On the basis of targeting the lower grades (1st- 3th year) and the higher grades (4th-6th year) elementary school students' sexuality education guidebooks published by Korea Ministry of Education & Human Resources Development, 71 preliminary items targeting the lower grades, 90 preliminary items targeting the higher grades were developed. 2. Through the validity test about the contents of the preliminary items three times, the items were regulated to 65 items targeting the lower grads and 57 items targeting the higher grades. And then, the preliminary items were re-regulated to 40 items separately. Then, pre-test which targeting each 30 students was enforced. 3.Finally, the evaluation tools for sexuality education that consisted of 40 items targeting the lower grades and the higher grades were developed. 4. eliability test of the developed tools, sexuality education evaluation tools showed alpha coefficient of internal consistency were 0.8355 (for the use of the lower grades) and 0.8881 (for the use of the higher grades). 5. o apply the developed sexuality education evaluation tools, 10-times sexuality education were carried out class unit and pre-post test were done using same questionnaire, which contains developed tool, there were significant difference in low grade (t=16.548, p=0.000), high grade (t=14.773, p=0.000). The results of this study suggest that the evaluation tool for sexuality education in elementary school may be a useful tool with a high degree of reliability and validity. In this sense, the evaluation tool for sexuality education developed by this study can be effectively utilized in Korea elementary schools.

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Study on the Emergency Protection System of Liquid Rocket Engine (액체로켓엔진 비상보호시스템 연구)

  • Kim, Seung-Han;Han, Yeoung-Min
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2011.11a
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    • pp.97-103
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    • 2011
  • This paper describes the main considerations for the development of engine emergency protection system and applications to preliminary engine development tests. Emergency protection system performed its role without failure to shutdown test very quickly for the prevention of development of malfunctioning of test articles, which protected test articles and test facility in all abnormal situation occurred during preliminary engine development test program. This results will be used for the development of engine emergency protection system.

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Development of Military Customer Satisfaction Index (군수품 고객만족지수 개발 연구)

  • 박성현;김용섭;홍현의;박봉균
    • Journal of Korean Society for Quality Management
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    • v.32 no.2
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    • pp.212-231
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    • 2004
  • It is very important to produce military goods for customers, and a customer satisfaction index should be developed for quality control of military goods. Seoul National University and Defense Quality Assurance Agency jointly developed MCSI (Military Customer Satisfaction Index). In this paper the model of MCSI is explained, and the sampling design and survey method is introduced. Also a preliminary test was undertaken, and its result is briefly explained.

Methane Engine Combustion Test Facility Construction and Preliminary Tests (메탄엔진 연소시험설비 구축 및 예비 시험들)

  • Kang, Cheolwoong;Hwang, Donghyun;Ahn, Jonghyeon;Lee, Junseo;Lee, Dain;Ahn, Kyubok
    • Journal of the Korean Society of Propulsion Engineers
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    • v.25 no.3
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    • pp.89-100
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    • 2021
  • This paper deals with the construction of a combustion test facility and preliminary tests for hot-firing tests of a methane engine. First, the combustion test facility for a 1 kN-class thrust chamber using liquid oxygen/gas methane as propellants was designed and built. Before hot-firing tests, the cold-flow tests of each propellant line and the ignition tests of torch igniter/afterburner were performed to verify propellant supply stability of the combustion test facility, operation of the control and measurement system, and successful ignition. Finally, a preliminary hot-firing test was conducted to measure the combustion efficiency, heat flux, and combustion stability of a thrust chamber prototype. The constructed combustion test facility will be helpfully used for basic research and development of methane engine thrust chambers.

In Situ Rockfall Tests for Evaluation of Rockfall Protection Fences (국내 낙석방지울타리의 적정성 파악을 위한 현장 실물 실험 및 설계기준 제시)

  • 구호본;박혁진;이경미;김규한;이재욱
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.11a
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    • pp.629-634
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    • 2000
  • Rockfall protection fence which is used for mitigation of rockfall hazard, has been constructed without consideration of lithology, height and dip angle of rock slope. However, those factors should be considered for the construction of the protection fence. In addition, the protection fence should be evaluated its performance by in-situ test in order to utilize the fence effectively. This is the first full sized rockfall test in Korea. For this test, the rock cut slope whose height is about 20 m and dip angle is 65 $^{\circ}$ has been chosen. Based on the preliminary simulation procedure, four different concrete balls (0.5 ton, 1.0 ton, 2.0 ton and 5.0 ton) were prepared and four different types of protection fence were constructed. The results of this test will be utilized in the establishment of rockfall protection fence construction manual.

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The Effect of Awareness towards Inclusive Education of Preliminary Elementary School Teachers on the Intention to Implement Instructional Adaptations for Students with Disabilities (예비초등교사의 통합교육에 대한 인식이 장애학생을 위한 교수적 수정 실행의지에 미치는 영향)

  • Kang, Young-Sim;Lee, Mia;Park, Ji-Yoon
    • Journal of Fisheries and Marine Sciences Education
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    • v.26 no.5
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    • pp.991-1002
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    • 2014
  • The purpose of the study is to analyze the difference of the intention to implement instructional adaptations for students with disabilities between preliminary teachers who agree on inclusive education and who do not agree on inclusive class. The subjects are 318 preliminary teachers who enrolled in the Busan national university of education(180 pro-inclusive preliminary teachers and 138 anti-inclusive preliminary teachers). The questionnaires are composed of currently demographic information, perception about inclusive education, and instructional adaptations. To examine the differences depend on the teachers' perception of inclusive education, descriptive statistics, and t-test were used. The results are as follow: Significant differences in total instructional adaptations and three sub-instructional adaptations(e.g., instructional environment, instructional groups, and instructional contents) were found between preliminary teachers who agree on inclusive education and who do not agree on inclusive education.

Development of Job-Esteem Scale for Korean Nurses (한국 간호사의 직업존중감 측정도구 개발)

  • Choi, Hyun Ju;Jung, Kwuy Im
    • Journal of Korean Academy of Nursing
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    • v.50 no.3
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    • pp.444-458
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    • 2020
  • Purpose: The purpose of this study was to develop the Job Esteem Scale for Korean Nurses (JES-KN) and verify its validity and reliability. Methods: Preliminary items were based on the attributes and indicators elicited from a concept analysis study on Korean nurses' job-esteem. The final preliminary tool for the main survey was confirmed through the content validity test of 10 experts and preliminary survey of 20 hospital nurses. The final preliminary scale was used on 350 hospital nurses in the scale testing phase for the main survey designed to test the validity and reliability of the scale. Results: The final scale consisted of 28 items and 6 factors, these factor explained 66.6% of the total variance. The correlation between the total score and factors ranged from .64 and .84, validating that each sub-factor is suitable to explain job esteem. The correlation coefficient between this scale and the Job Satisfaction Scale for Clinical Nurses ranged from .41 to .70, and the internal consistency for the scale using Cronbach's α for the total items was .94. Conclusion: The JES-KN is a valid and reliable tool that reflects the reality of clinical sites accordingly. The JES-KN may well be used effectively to assess and evaluate the job esteem of Korean nurses.