• Title/Summary/Keyword: Pre-evaluation

Search Result 2,096, Processing Time 0.025 seconds

Evaluation of Particle Removal Efficiency during Jet Spray and Megasonic Cleaning for Aluminum Coated Wafers

  • Choi, Hoomi;Min, Jaewon;Kulkarni, Atul;Ahn, Youngki;Kim, Taesung
    • Journal of the Semiconductor & Display Technology
    • /
    • v.11 no.3
    • /
    • pp.7-11
    • /
    • 2012
  • Among various wet cleaning methods, megasonic and jet spray gained their popularity in single wafer cleaning process for the efficient removal of particulate contaminants from the wafer surface. In the present study, we evaluated these two cleaning methods for particle removal efficiency (PRE) and pattern damage on the aluminum layered wafer surface. Also the effect of $CO_2$ dissolved water in jet spray cleaning is assessed by measuring PRE. It is observed that the jet spray cleaning process is more effective in terms of PRE and pattern damage compared to megasonic cleaning and the mixing of $CO_2$ in the water during jet sprays further increases the PRE. We believe that the outcome of the present study is useful for the semiconductor cleaning process engineers and researchers.

The Influence of Factors Related to Preparation by Pre-Service Teachers for Gender Equity Education and Teaching Gender Equity

  • Kwon, Yoo-Jin;Jeon, Se-Kyung
    • International Journal of Human Ecology
    • /
    • v.11 no.1
    • /
    • pp.97-107
    • /
    • 2010
  • Gender equity education is ineffective in a public school system even though gender equity education is a current issue in South Korean education. One of the problems is attributed to teacher education because no better gender equity education can be accomplished without teacher preparation. Therefore, the effectiveness of teachers is a very important keyword in teacher education. This study examines learning experience, gender equity value, teacher preparation for gender equity education of pre-service teachers in Gonju, South Korea, the factors that influence teacher preparation for gender equity education, and the instruction of gender equity. A survey was delivered to pre-service teachers in 2008, and the data of 350 pre-service teachers were analyzed. MANOVA and Multiple Regressions were used for analyzing the data. The results will contribute to the development of effective teacher education for gender equity education and information on a partnership between the family and the public school system that is centered on gender equity education.

Case Study of Flipped-learning on a Signal Processing Class (신호처리 교과목에 대한 플립러닝 적용사례)

  • Yoo, Jae Ha
    • Journal of Practical Engineering Education
    • /
    • v.9 no.2
    • /
    • pp.125-132
    • /
    • 2017
  • This paper is a study on the application of flipped learning, which is known as a teaching method that provides effective learning, to signal processing subjects. The teaching - learning model used for the class and the implementation examples for three years are described. In-class can be judged to be a relatively successful class, but organization of the video data provided in the pre-class and evaluation of whether or not to study pre-class video have to be improved.

A Study on the Strategy of Performance Assessment based on Classroom (수업 연계 수행평가 전략 설계 방안 연구)

  • Won, Hyo-Heon;Heo, Gyun
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.27 no.1
    • /
    • pp.125-132
    • /
    • 2015
  • The purpose of this study was to search the concept and meaning of performance assessment(PA) in the classroom, and the to proposed some strategies to apply PA. The result of this study was presented below. First, differentiation strategy is necessary in the evaluation goal. Individualization will be an example of differentiation strategy in the evaluation of group goal. Second, various strategies are needed based on the subjects of evaluation. Self-evaluation, peer-evaluation, and small group-evaluation are some examples evaluation for the subjects. Third, there is a need for phase-strategy assessment. For the class associated performance assessment, we have to consider the evaluation activities based on the time likes before (pre), on, and after class. How to select the evaluation task is also one of the key sucess factors for improving the class associated performance assessment.

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
    • /
    • v.8 no.3
    • /
    • pp.334-343
    • /
    • 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.

  • PDF

Pressure Control of Staged Combustion Liquid Rocket Engine (다단연소사이클 액체 로켓엔진의 압력제어에 대한 연구)

  • Hwang, Changhwan;Lee, Kwangjin;Woo, Seongphil;Im, Ji-Hyuk;Jeon, Junsu;Lee, Jungho;Yoo, Byungil;Han, Yeoungmin
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.22 no.4
    • /
    • pp.18-23
    • /
    • 2018
  • For the control of pre-burner combustion pressure, the open angle of the TTR (Throttle for Thrust Regulation) valve was varied from $143^{\circ}$ to $185^{\circ}$ while testing cold flow, ignition, and combustion. The major performance variables of rocket engines and hydraulic performance of the TTR valve regarding the open angle were verified. However, the controllability of pre-burner combustion pressure was not verified due to the limitations of the test. Comprehensive research will be done after addressing these problems.

A Study on Analysis Criteria for AI Service Impact Assessment (인공지능 서비스 영향성 평가를 위한 분석 기준 연구)

  • Soonduck, Yoo
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.23 no.1
    • /
    • pp.7-13
    • /
    • 2023
  • This study investigated the criteria for evaluating the impact of artificial intelligence services. The study classified AI evaluation targets into two areas: AI service and AI technology, and identified influence, sustainability, efficiency, effectiveness, and appropriateness as potential evaluation criteria. The time aspect of AI service evaluation was divided into pre-evaluation and post-evaluation, with pre-evaluation focused on reviewing items during development and design. The AI service area was classified into public, private, and mixed forms, and the impact assessment was classified as vertical or horizontal. The application of AI services was divided into normative and regulatory aspects, and the purpose of the evaluation could be impact or process evaluation. The subject and field of the AI service could also be used for classification purposes. The results of this study can be used to support the creation of AI service impact policies and countermeasures. However, further research is needed to develop specific indicators based on the criteria identified in this study to evaluate the impact of AI services.

Analysis of Science Lesson Plan of Pre-Service Elementary Teachers about Condensation (초등 예비교사의 응결 차시에 대한 과학 수업 설계 분석)

  • Sung, SeungMin;Yeo, Sang-Ihn
    • Journal of Science Education
    • /
    • v.45 no.2
    • /
    • pp.172-186
    • /
    • 2021
  • The purpose of this study is to analyze the science lesson plan of pre-service elementary teachers about condensation. Pre-service elementary school teachers in A national university of education was included in this study. Through the analysis of prior research and expert review, a framework for analysis of science lesson plan of pre-service elementary teachers was derived. The results of the using the analysis frame are as follows: First, the ability to apply the instructional model in the science lesson plan about condensation differences in pre-service elementary teachers need to be enhanced due to deviations, and teaching on the exact understanding of condensation-related concepts of pre-service elementary teachers is also needed. Second, there is also a deviation of pre-service elementary teachers in the beginning, development, and finishing composition of lesson course, so feedback should be supplemented. Third, in the sub-domain of lesson environment, there was a demand for specific know-how on the lesson environment. Therefore, support is needed for related PCK growth. Fourth, the sub-domain of lesson evaluation have a variety of perspectives on timing and subjects, and some missing about learning objectives in the composition of evaluation content are found to require complementary teaching. In order to improve this situation, it was found that there was a need to prepare conditions for improving science teaching professionalism of pre-service elementary teachers through in-depth discussions on the teaching methods and organization related to science education in the university of education course.

Effects of Oxidation and Hot Corrosion on the Erosion of Silicon Nitride

  • Kim, Jong Jip
    • Corrosion Science and Technology
    • /
    • v.4 no.4
    • /
    • pp.136-139
    • /
    • 2005
  • The effect of oxidation and hot corrosion on the solid particle erosion was investigated for hot-pressed silicon nitride using as-polished, pre-oxidized and pre-corroded specimens by molten sodium sulfates. Erosion tests were performed at 22, 500 and $900^{\circ}C$ using angular silicon carbide particles of mean diameter $100{\mu}m$. Experimental results show that solid particle erosion rate of silicon nitride increases with increasing temperature for as-polished or pre-oxidized specimens in consistent with the prediction of a theoretical model. Erosion rate of pre-oxidized specimens is lower than that of as-polished specimens at $22^{\circ}C$, but it is higher at $900^{\circ}C$. Lower erosion rate at $22^{\circ}C$ in the pre-oxidized specimens is attributed due to the blunting of surface flaws, and the higher erosion rate at $900^{\circ}C$ is due to brittle lateral cracking. Erosion rate of pre-corroded specimens decreases with increasing temperature. Less erosion at $900^{\circ}C$ than at $22^{\circ}C$ is associated with the liquid corrosion products sealing off pores at $900^{\circ}C$ and the absence of inter-granular crack propagation observed at $22^{\circ}C$.

A Study on the Threshold Condition of Crack Propagation for Pre-Crack and Micro-Hole Specimens (프리크랙과 微小圓孔材의 크랙成長 下限界條件에 관한 硏究)

  • 송삼홍;윤명진
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.12 no.2
    • /
    • pp.278-285
    • /
    • 1988
  • The Critical size of artificially induced micro-holes in 0.17%, 0.36% Carbon steel Specimens with Spheroidized Cementite and in 0.17% carbon steel specimens with martensite structure is compared with annealed pre-crack in order to discuss the physical meaning of the fatigue limit and evaluation of the tolerant micro flaw size at the stress level of the fatigue limit. Results obtained were summarized as follows; (1) In this study, non-propagating crack length of Smooth specimen and critical pre-crack length (lc) is coincide. (2) In the carbon steels with spheroidized cementite structure, critical pre-crack length (lc) and allowable micro-hole size (dc) is coincide each other at the fatigue limit level. (3) It has been published that there exists a particular size of micro-hole which has no effect on the fatigue limit. In this study, the micro-hole of critical size can be regarded as equivalent to a tolerant micro flaw which would not reduce the fatigue limit.