• 제목/요약/키워드: Class scale

검색결과 889건 처리시간 0.029초

75톤급 액체로켓엔진 1/2.5-scale 연소기 연소시험 결과 (Combustion Test Results of 1/2.5-scale Thrust Chamber for 75tonf-Class Liquid Rocket Engine)

  • 김종규;한영민;이광진;임병직;안규복;김문기;서성현;최환석
    • 한국추진공학회:학술대회논문집
    • /
    • 한국추진공학회 2009년도 제33회 추계학술대회논문집
    • /
    • pp.69-73
    • /
    • 2009
  • 75톤급 액체로켓엔진 연소기의 1/2.5-scale 연소기의 시험 결과를 기술하였다. 연소기의 연소압력은 60 bar, 추진제 유량은 약 89 kg/s 그리고 노즐 팽창비는 12이다. 연소성능 및 재생냉각 성능, 연소기의 내구성 확인을 위한 수회의 설계점 연소시험과 저압조건에서의 작동성 및 연소성능을 검증하기 위한 시험이 수행되었다. 모든 연소시험은 하드웨어의 손상 없이 성공적으로 수행되었다. 본 시험결과는 향후 75톤급 연소기의 저압 연소 조건에서의 시험 가능성을 제시하고, 설계점 조건에서의 연소성능을 예측하는 기본 데이터로 활용될 수 있을 것이다.

  • PDF

초등 교사를 위한 ADHD 아동 교수법 코칭 프로그램 개발 및 효과 (Development and Effects of an Instructional Coaching Program Regarding Children with Attention Deficit Hyperactivity Disorder for Elementary School Teachers)

  • 박신정;박완주
    • 대한간호학회지
    • /
    • 제47권3호
    • /
    • pp.305-318
    • /
    • 2017
  • Purpose: The aim of this study was to identify the effects of a newly developed instructional coaching program regarding Attention Deficit Hyperactivity Disorder (ADHD) for teachers. Methods: Seventy teachers participated in this study involving a nonequivalent control group and a pretest-posttest design. The instructional coaching program consisted of eight 60-minute sessions. The program was developed through a theoretical development program involving six steps. To evaluate the effects of the program, data were collected through self-report questionnaires including the Knowledge Scale of Attention Deficit Disorder, Attitude Scale of Primary School Teachers Experiencing Students with ADHD, Practice Scale of Educational Intervention Activity, and the Korean ADHD Rating Scale. Data were analyzed with an independent t test, a chi-square test, and an ANCOVA using SPSS WIN version 20. Results: The intervention program consisted of 3 sectors, 8 subjects, and 24 content items. The experimental group showed a significant improvement in attitudes toward ADHD (F=22.83, p<.001). In addition, teacher's knowledge regarding ADHD (F=7.16, p=.010) and the implementation of instructional interventions (F=4.29, p=.043) improved. Further, teachers reported a reduction in children's ADHD-related behavior (F=4.34, p=.041). Results showed that the coaching program made a positive contribution to teaching skills and understanding of school-age children with ADHD. Conclusion: The instructional coaching program was well structured and significantly improved not only teachers'attitudes, knowledge, and teaching skills but also the behavior of children with ADHD in class. Therefore, the program is recommended as a means of facilitating teaching and managing children with ADHD in class.

예비특수교사의 체육교수불안 척도 개발 및 타당화 (Development and Validation of Physical Education Teaching Anxiety Scale for Preservice Special Teacher)

  • 이용국
    • 한국체육학회지인문사회과학편
    • /
    • 제57권3호
    • /
    • pp.375-389
    • /
    • 2018
  • 이 연구는 특수(체육)교육 예비교사들의 체육교수불안 척도 개발 및 타당성을 검증하는데 연구의 목적을 두었다. 이에 따른 연구목적을 달성하기 위한 연구절차는 3단계에 따라 이루어졌다. 1단계에서는 특수(체육)교육 예비교사의 체육교수불안 구성 요인을 도출하기 위해 100명의 특수(체육)교육 예비교사를 대상으로 개방형 질문지를 통한 예비문항을 설정하고, 이에 따른 응답을 통해 얻어진 결과를 바탕으로 귀납적 내용분석을 실시하였다. 다음 2단계에서는 1단계에서 도출된 체육교수불안 구성 요인을 바탕으로 100명의 특수(체육)교육 예비교사를 대상으로 탐색적 요인분석 통해 문항들의 이론구조에 적합한지 검증을 통하여 구인타당성을 확보하였다. 그리고 마지막 3단계에서는 특수(체육)교육 예비교사 300명을 대상으로 확인적 요인분석을 통해 척도의 구인타당성을 확보하였으며, t-test 차이검증을 실시하여 척도의 외적타당도를 확보하였다. 이를 통해 분석된 내용을 중심으로 문항을 구성하였다. 그 결과 특수(체육)교육 예비교사의 체육교수불안 척도는 수업지식(4문항), 학생이해(4문항), 수업환경(3문항), 수업관리(3)문항으로 총 14개 문항으로 구성되었다.

대학생의 스킨스쿠버 참여 동기와 재미요인 및 대학생활만족의 인과관계 규명 (Investigation Causal Relationship among Skin SCUBA Participation Motivation, Enjoyment and College Life Satisfaction of College Students)

  • 이민구;김동주;장재용
    • 수산해양교육연구
    • /
    • 제28권2호
    • /
    • pp.525-538
    • /
    • 2016
  • This study is to investigate the effect of the amusement factor and the motive of participation in skin-scuba class on the satisfaction with university life with the university students participating in the skin-scuba class and to provide the practical research data for the development of the marine sports, for the proper operation of skin-scuba class, and for the leisure life which the university students may lack. For these purposes, technical statistics between questions were disposed in order to grasp the average and standard deviation on each variables, exploratory factor analysis and reliability analysis were conducted for the reliability and validity of the scale, and correlation analysis and multiple regression analysis were conducted to test the casuality of amusement factor, the motive of participation in skin-scuba class and the satisfaction with university life as the research methods. Research results showed that it was confirmed that the amusement factor and the motive of participation in skin-scuba class act as the important variables in the satisfaction with university life and it was predicted that the motive of participation in skin-scuba class and the amusement factor had interrelation with parameter. Therefore, a variety of programs reflecting the amusement factors should motivate the university students to particiapte in the skin-scuba class to increase the satisfaction with university life and to encourage the re-participation of students.

The tunnel model tests of material development in different surrounding rock grades and the force laws in whole excavation-support processes

  • Jian Zhou;Zhi Ding;Jinkun Huang;Xinan Yang;Mingjie Ma
    • Geomechanics and Engineering
    • /
    • 제36권1호
    • /
    • pp.51-69
    • /
    • 2024
  • Currently, composite lining mountain tunnels in China are generally classified based on the [BQ] method for the surrounding rock grade. Increasingly, tunnel field construction is replicated indoors for scale down model tests. However, the development of analogous materials for model tests of composite lining tunnels with different surrounding rock grades is still unclear. In this study, typical Class III and V surrounding rock analogous materials and corresponding composite lining support materials were developed. The whole processes of excavation-support dynamics of the mountain tunnels were simulated. Data on the variation of deformations, contact pressures and strains on the surrounding rock were obtained. Finally, a comparative analysis between model tests and numerical simulations was performed to verify the rationality of analogous material development. The following useful conclusions were obtained by analyzing the data from the tests. The main analogous materials of Class III surrounding rock are barite powder, high-strength gypsum and quartz sand with fly ash, quartz sand, anhydrous ethanol and rosin for Class V surrounding rock. Analogous materials for rockbolts, steel arches are replaced by aluminum bar and iron bar respectively with both shotcrete and secondary lining corresponding to gypsum and water. In addition, load release rate of Class V surrounding rock should be less than Class III surrounding rock. The fenestration level had large influence on the load sharing ratio of the secondary lining, with a difference of more than 30%, while the influence of the support time was smaller. The Sharing ratios of secondary lining in Class III surrounding rock do not exceed 12%, while those of Class V surrounding rock exceed 40%. The overall difference between the results of model tests and numerical simulations is small, which verifies the feasibility of similar material development in this study.

횡충돌 하중을 받는 비보강 강판의 구조거동에 대한 크기 효과 (Scale Effects on the Structural Behavior of Steel Unstiffened Plates Subjected to Lateral Collisions)

  • 조상래;박정열;송승욱;박상현
    • 대한조선학회논문집
    • /
    • 제55권2호
    • /
    • pp.178-186
    • /
    • 2018
  • The scale effects on the permanent deformations and fractures of structures subjected to impact loadings have been aware by structural engineers for a long time. Experimental investigations have been performed with various structures to demonstrate the effects, but very few are directly related with marine structural elements. Furthermore, the causes of the scale effects have not clearly been answered yet. In this study, to quantify the scale effects on the permanent deflections, lateral collision tests were performed on steel unstiffened plates and the numerical analyses of the tested models were also conducted using a commercial package, Abaqus. After the substantiation of the numerical tool using the test results, a parametric study was carried out considering and neglecting the strain-rate hardening. Based upon the parametric study results, it may be concluded that the main cause of the scale effects on the permanent deflections of steel unstiffened plates subjected to lateral collision loads is the strain-rate effects.

A Systematic Review on Trunk Impairment Scale for Stroke Patients

  • Lee, Min Joo;Lee, Seul;Park, Dae-Sung
    • Physical Therapy Rehabilitation Science
    • /
    • 제10권3호
    • /
    • pp.379-386
    • /
    • 2021
  • Objective: The purpose of this study was to systematically review the trunk impairment scale that are used to assess the trunk control of stroke patients. Design: A systematic review Methods: Stroke subjects were categorized as acute, subacute, chronic. In this systematic review, the studies published between 2000 and 2020 were selected. A literature search using the keywords 'QUADAS', 'stroke', 'trunk impairment scale'. Data sources included RISS, GOOGLE Scholar and DBpia. We assessed the quality of assessment tools using Quality Assessment of Diagnostic Accuracy Studies tool. Results: We reviewed 18 studies. 7 of the 18 studies reported reliability results, 10 reported validity results. The QUADAS tool quality evaluation of 17 literatures extracted except for one randomized control test among 18 literatures showed a range of 3 to 13 points. 5 of the 18 studies are presented with the Cronbach alpha coefficient indicating reliability using internal consistency, all of which are more than 0.8. All studies that presented test-retest reliability, intra-rater reliability, and inter-rater reliability showed high agreement with an intra-class correlation coefficient of 0.75 or more. Conclusions: A systematic review of the study of the application of the trunk impairment scale for stroke patients will help provide criteria for future studies and application of the trunk impairment scale in clinical practice.

요통(腰痛) 및 요각통(腰脚痛) 환자에 있어 약침치료(藥鍼治療)의 호전도에 대한 임상적 고찰 (The Clinical Studies about improvement rate in managering patients who had lumbago and pain in loin & feet with herbal-acupunture therapy)

  • 이동현;김효수;위통순
    • 대한약침학회지
    • /
    • 제7권2호
    • /
    • pp.97-105
    • /
    • 2004
  • Objectives : The purpose of this study is to compare the improvement rate in managering patients who had lumbago and pain in loin & feet by herbal-acupunture therapy with conservative treatment. Methods : 40patients who invited from March. 2003 to May. 2004 with lumbago and pain in loin & feet inve, were divided into two classes. A class was managed with conservative treatment(acupuncture, herb med, negative therapy, bed rest and physical therapy) and herbal-acupuncture therapy, the other class was managed with conservative treatment only. Two classes were distributed by sex and age, therapeutic periods, radiolographic results and therapeutic results that checked with VAS(visual analog scale) and ODI(Oswestry disability index). Results : According to VAS and OBI results, A class was managed with conservative treatment and herbal-acupuncture therapy shows the improvement in controling the pain of lumbago etc. comparing with the other class.

중산층 이상 가족이 인식하는 치매노인 그룹흠의 장점과 국내 도입의 문제점 (Merits of this Group Homes far the Elderly with Dementia Recognized by Middle and Upper Class Families, and Potential Obstacles to its Introduction in Korea)

  • 김대년;권오정;최정선
    • 가정과삶의질연구
    • /
    • 제19권6호
    • /
    • pp.113-128
    • /
    • 2001
  • middle and upper class families, and examine obstacles to their introduction in Korea. Since a few large-scale facilities for the elderly with dementia have been provided for only low-income families free of charge, the necessity of group homes for middle and upper class families willing to pay for such services has become an issue recently in order to lessen the burden on families, as well as to promote the well-being of the dementia victims themselves. The survey was conducted by questionnaires collected from 577 respondents from middle and upper class families. The results of the survey were as follows: The merits of the group homes were 1)decreasing loneliness of the elderly, 2)providing active and stimulating environments allowing for participation everyday life activities, and 3)lessening the emotional and physical burden on the caring families. Potential obstacles to its introduction in Korea were 1)the difficulty of finding sites to build the group home because of the negative perception of people with disabilities and a NIMBY(Not In My Back Yard) reaction to the construction of it and 2)the economic burden on the caring family. Surprisingly, the guilt factor associated with sending the parents into group homes was not considered as a big obstacle. Referring to results of this study, it is asserted that group homes for the elderly with dementia would be embraced throughout the country if Koreans could have the chance to understand what group homes are.

  • PDF