• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2010년도 제35회 추계학술대회논문집
• /
• pp.581-584
• /
• 2010

한국항공우주연구원에서는 2020년대에 수행하기로 계획되어 있는 달탐사를 준비하기 위해 달 탐사선 및 착륙선 추진시스템의 기본 설계를 진행하고 있으며 추진시스템의 설계 검증 및 추력기의 성능 검증을 위한 착륙 시험 계획을 진행하고 있다. 올해는 그 첫 단계로 추진시스템의 개념 설계가 이루어졌으며 지상 시험을 수행하기 위한 200N급 단일추진제 추력기의 설계가 이루어졌다. 본 논문에서는 추진계 설계를 위한 trade-off 연구 결과와 추진계 및 추력기의 기본 설계에 대해 소개할 예정이다.

• 복식
• /
• 제59권9호
• /
• pp.16-25
• /
• 2009

The purpose of this study is to develop pattern of a Upper Garment Prototype for late elementary school aged girls. The body of late elementary school aged girls changes steadily up to the adult and is characterized by its periodic noticeable physical distinctions. This study is selected a test pattern from 3 existing patterns through a preliminary wearing test, conducted wearing tests, and sensory evaluations three times to review and improve the pattern, and presented the pattern of late elementary school aged girls. The research pattern was developed considering aesthetic and functional aspect. The average score of sensory evaluation on appearance was 4.13 for the research pattern, which was higher than 2.74 for the test pattern. The according to the results of verifying significant differences in the test items between the two patterns through the t-test, in the items such as pleats in the line of a waist, the ease of the girth of a waist, the location of shoulder line was superior to the test pattern. The average score of the sensory evaluation on functionality was 4.91 for the research pattern, which was higher than 3.90 for the test pattern. The research pattern is superior to the test pattern in static posture, dynamic posture than the test pattern.

• 한국연소학회:학술대회논문집
• /
• 한국연소학회 1997년도 제15회 KOSCO SYMPOSIUM 논문집
• /
• pp.135-151
• /
• 1997

The preliminary design and performance test for determining dimensions of gas turbine combustor were investigated. The combustor design program was developed and applied to design our combustor. and detailed design for determining of swirler. dome and liner holes were performed experimentally. The swirler. which govern the combustion characteristics of combustor, was determined $40^{\circ}$ as swirl angle at first performance test. After second performance test the swirler was re-determined by 24 mm i.d.. 34 mm o.d., and swirl angle of $45^{\circ}$. The geometry of liner holes were determined by considering the flame stability and recirculation zone size. It was found that flame can be more easily stabilized by adjusting the swirier dimensions rather than liner holes. The geometry of swirler and liner holes were re-determined by final performance test with dilution holes. Also. the performance of combustor was evaluated by analysis of exhaust gases.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 하계학술대회 논문집 C
• /
• pp.1750-1752
• /
• 2003

This paper, as a preliminary study, presents the important consideration in laboratory planning and designing 4.2MV impulse voltage generator(IVG), which enable to test and evaluate the UHV dielectric performance of power electric apparatus up to 765kv-class. To fix and confirm the kinds of loads and their capacities to be tested by KERI hereafter, wide investigation and an analysis of test objects, especially heavy electric apparatus of Korea, according to their ratings and test voltages have been conducted. With the special consideration concerning other matters in designing of 4.2MV IVG have been described with the practical examples and references.

• 한국치위생학회지
• /
• 제13권4호
• /
• pp.659-668
• /
• 2013

Objectives : The purpose of this study is to analyze the causes of stress driven by the national examination and to find out correlation between stress factors and students' general characteristics. Methods : Data were collected from self-reported questionnaires by dental hygiene students in D university in February, 2012. Results : Those having good high school GPAs (p<.05) and high preliminary test scores (p<.01) towards dental hygienist (p<.05). National license examination was the most stressful factor for 54.2% of the students. Much more stressful pressure goes to students of non-scheduled admission (p<.01), students who graduated from vocational high schools(p<.01), students with good high school GPAs (p<.05), and having high preliminary test scores(p<.05). Most of the students tended to bear the burden on national written examination with an average of 4.17. The most difficult subject was oral biology introduction (average 4.52). Oral biology introduction was more stressful to students of early admission, students graduating from vocational high schools (p<.05), students with good high school GPAs (p<.05), and students who had relatively low preliminary test scores (p<.001). Conclusions : It is crucial to reduce stress factors and to develop related programs.

• Child Health Nursing Research
• /
• 제12권2호
• /
• pp.233-243
• /
• 2006

Purpose: This study was aimed to develop a WBI(Web Based Instruction) program on safety for 6th grades of elementary school students and to test the effects of it. Method: The web site is http://www.safeschool.co.kr. The effect of it was tested from Mar 24, to Apr 30, 2003. The subjects were 150 students. Data were analyzed with descriptive statistics, and $x^2$ test, t-test, and repeated measure ANOVA. Result: In the knowledge of the safety precaution, the preliminary test was mean 17.8, immediate post-test was mean 20.9 and 4 weeks post-test was mean 20.9, there were significant differences statistically among three points of time. In the attitude of the safety precaution, the preliminary test was mean 75.1, the immediate post-test was mean 80.8 and 4 weeks post-test was mean 80.4, which showed significant difference statistically among three points of time. For the motive of learning to the safety precaution, it was significantly higher statistically in the WBI. As a result, the WBI group had totally longer effects on knowledge, attitude and motivation of the safety accident prevention than the textbook-based instruction. Conclusion: WBI program be used in each class to provide more effective safety instruction.

• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
• /
• pp.1016-1020
• /
• 2017

본 연구는 실물형 발사체 연소실에서 발생하는 연소불안정을 모사하여 검증하는 시험 설비의 개발을 위해 진행됐다. 연소불안정 모사시험설비 개발을 위해 3개의 인젝터를 일렬로 배치한 분리형 헤드 엔진을 설계/제작했으며, 예비운영을 통해 검증했다. 분리형 헤드에 대한 수류시험을 통해 차압에 따른 유량과 분무형태를 확인했으며, 실추진제 분무시험와 연소시험이 진행됐다. 10bar에서 예비운용시험을 진행하였으며, 연소 시험 결과 연소실 압력이 목표 압력에 비해 상당히 낮게 계측되었다. 이는 저압 시험이었기 때문으로 판단되며, 향후 고압 시험에서 해결될 것으로 예상된다.

• 보건교육건강증진학회지
• /
• 제17권2호
• /
• pp.99-110
• /
• 2000

The purpose of this research was to provide basic data to the welfare policy for the aged by studying the relation of health concern, health behavior, and subjective health condition between the aged and the preliminary aged group. Subjects were composed of a total of 259 (116 males, 143 females) living in seoul, aged 50-64(preliminary old people) and over 65(old people), and they were asked to answer the survey Questionnaires The data were analyzed by descriptive statistics, chi-square test, and spearman's correlation coefficient. As a result of the study, the preliminary aged group was significant than the aged group in all three variables. In the relation of health concern and health behavior, there was significance both for the preliminary aged(p〈0.01) and the aged group(p〈0.001). Also, there was significance in the relation of health behavior and subjective health condition of two groups(p〈0.001). However, in the relation of subjective health condition and health concern, there was significance only for the aged group(p〈0.001). For the correlation among three variables, there was significance in the relation between health concern and health behavior and between health behavior and subjective health condition of the preliminary aged group(p〈0.01), but there was significance in the relation between health concern and health behavior and between health behavior and subjective health condition of the aged group(p〈0.01).

• 한국환경과학회지
• /
• 제32권1호
• /
• pp.1-9
• /
• 2023

In this study, a horticultural therapy program was performed by employing the anger experienced by people during daily life activities in the emotion regulation strategy-based program to identify the influence of the horticultural program on anger control in the caregivers for patients with dementia. To measure this influence, two tools were used: a self-administered questionnaire survey, which is a subjective test, and an instrumental test, which can measure the physical index that detects the physical changes through anger. For the preliminary test, depression, stress, self-esteem, anxiety, and anger state-characteristic were tested using the self-administered questionnaire. For the follow-up test, the self-administered survey and the test using the physical index were performed in a manner similar to that of the preliminary test. The self-administered questionnaire comprised questions suitable to this study and considered the age, education level, and economic aspect of the subjects. The test results indicated that the experimental group subjected to the emotion regulation strategy-based horticultural therapy showed very significant reduction in depression and anger and significant reduction in stress, self-esteem, and anxiety. In the physical index test, the systolic and diastolic blood pressures were reduced, and the pulse rate and respiration rate reduced before and after the therapy, thus, proving the effectiveness of the therapy in anger control.

• 한국진공학회지
• /
• 제13권2호
• /
• pp.47-53
• /
• 2004

국내 진공기술 기반을 구축하는 국가사업의 일환으로 게터펌프 성능평가장치를 개발하고 있다. 본격적으로 장치를 구성하기 전에 평가절차의 개발, 장치 설계요건 및 사양을 확정하기 위해 예비실험장치를 만들었다. 이 장치를 이용하여 밀봉형 기기에 들어가는 비교적 활성화 온도가 낮은 게터 소자들의 특성평가 절차를 만들고 이를 적용하여 수소, 일산화탄소, 질소 등에 대해 배기속도와 배기용량을 측정해 보았다. 주로 고순도 기체 공급장치용으로 국내에서 개발된 게터 소자와 램프용으로 널리 쓰이는 외국제품의 배기성능을 비교해 보았다.