• Title/Summary/Keyword: 유용영역

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쌍안정 진동형 에너지 하베스터의 특성

  • Jeong, Ji-Hyeon;Seok, Jong-Won
    • Journal of the KSME
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    • v.55 no.4
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    • pp.43-47
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    • 2015
  • 이 글에서는 쌍안정 진동형 에너지 하베스터에 대한 필요성과 유용성 및 이의 동적 특성을 소개하고, 쌍안정 특성을 이용하여 넓은 영역의 주파수 성분에 대해 동조 가능하도록 하는 주파수 광대역화 기술에 대해 설명하고자 한다.

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A Study of high power microwave generator (대 출력 마이크로파 발생장치 연구)

  • Kim, Won-Sop
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.1318-1319
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    • 2008
  • 본 연구는 대출력 마이크로파를 발생하기 위한 장치의 일원인 후진파 발진기에 대하여 연구하였다. 대전력 마이크로파를 발생시키는 다른것과 비교하면 소형이고 구조가 간단하게 할 수 있는 장점이 있어 매우 유용하다. 따라서 본 연구에서는 고주파 영역에서 대전력 발생이 이루어졌으며 실험에 대구경 후진파 발진기를 이용하여 마이크로파출력이 현저히 향상된것을 알았다.

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중학교 함수영역에서 발생하는 수학적 오류에 대한 연구

  • 송순희;오정현
    • The Mathematical Education
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    • v.36 no.1
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    • pp.11-22
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    • 1997
  • 교육의 목적은 창조적인 인간상(creativity), 유용성 있는 인간상(utilitarian), 심미감 있는 인간상(esthetic)의 구현으로서, 이에 따르는 수학교육의 목적은 크게 두 가지로 나누어 생각할 수 있다. 하나는 수학 지식의 습득, 기능의 습득과 같은 직접적인 것으로 그것들의 응용 및 적용이며, 다른 하나는 간접적인 것으로 수학적 사고의 신장과 수학적 태도의 함양이다.(중략)

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Automatic Extraction and Coding of Multi-ROI (다중 관심영역의 자동 추출 및 부호화 방법)

  • Seo, Yeong-Geon;Hong, Do-Soon;Park, Jae-Heung
    • Journal of Digital Contents Society
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    • v.12 no.1
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    • pp.1-9
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    • 2011
  • JPEG2000 offers the technique which compresses the interested regions with higher quality than the background. It is called by an ROI(Region-of-Interest) coding method. In this paper, we use images including the human faces, which are processed uppermost and compressed with high quality. The proposed method consists of 2 steps. The first step extracts some faces and the second one is ROI coding. To extract the faces, the method cuts or scale-downs some regions with $20{\times}20$ window pixels for all the pixels of the image, and after preprocessing, recognizes the faces using neural networks. Each extracted region is identified by ROI mask and then ROI-coded using Maxshift method. After then, the image is compressed and saved using EBCOT. The existing methods searched the ROI by edge distributions. On the contrary, the proposed method uses human intellect. And the experiment shows that the method is sufficiently useful with images having several human faces.

Effectiveness Measurement of a Double-Tube Heat Exchanger for a Hydrogen Liquefaction System (수소액화 시스템용 이중관 열교환기의 유용도 측정)

  • Choi, H.J.;Baik, J.H.;Kang, B.H.;Choi, Y.D.
    • Journal of Hydrogen and New Energy
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    • v.10 no.1
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    • pp.19-26
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    • 1999
  • The effectiveness of a double-tube heat exchanger has been investigated experimentally. This problem is of particular interest in the design of the heat exchanger in a hydrogen liquefaction system. Temperature, pressure, and mass flow rate for hydrogen were measured both in inner tube and in annulus of a double-tube heat exchanger. The effectiveness could be evaluated from the measured temperature and mass flow rate. It is found that the effectiveness increases with an increase in the heat transfer area of a double-tube heat exchanger and with a decrease of the heat capacity ratio. But the increase rate of the effectiveness decreased with a decrease of the heat capacity ratio. Therefore, it is presented that a criterion for selecting the heat exchanger length and heat capacity ratio to obtain the effectiveness required in a hydrogen liquefaction system.

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Vaccine Evaluation Studies Performed in Korea from 2000 to 2014 (2000-2014년 한국에서 수행된 백신 유용성 평가 연구)

  • Cha, Jihei;Kim, Han Wool;Lee, Soyoung;Cho, Hye Kyung;Ahn, Jong Gyun;Kim, Kyung-Hyo
    • Pediatric Infection and Vaccine
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    • v.23 no.2
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    • pp.117-127
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    • 2016
  • Purpose: Vaccine evaluation studies were initiated from 2000 by the Ministry of Food and Drug Safety to produce proper data about the safety and immunogenicity of vaccines. The purpose of this study was to review studies and reports on evaluation of vaccine such as immunogenicity, efficacy, effectiveness, safety and other related topics in order to find and analyze the data on the usefulness of each vaccine. Methods: From 2000 to 2014, the project "The vaccine evaluation" had been performed by several researchers, and studies and reports of vaccine evaluation. We reviewed the results and outcomes of studies regarding the evaluation of vaccine's usefulness and analyzed the possibilities of applying these data for establishing vaccine policies. For each vaccine, data analysis and organization were done according to evaluation fields. Results: A total of 83 studies were performed on vaccines from 2000 to 2014. For each vaccine, 8 studies were performed on BCG, 14 on DTaP/Td, 1 on poliovirus, 5 on Hib, 3 on pneumococcus, 11 on influenza, 3 on hepatitis A, 11 on MMR, 11 on varicella, and 16 on Japanese encephalitis. All studies were analyzed by the following evaluation area, such as safety, immunogenicity, seroprevalence, persistence of immunity, efficacy, effectiveness, vaccine evaluation methods, quality control product for vaccine, and others. Conclusions: Vaccine evaluation studies performed in Korea may be useful as references for establishing vaccination strategy and policy and could be used as baseline data for future studies on vaccine evaluation, vaccine policy establishment, and public/expert vaccine education in Korea.

A Study on High School Students′ Interests and Usefulness of TechnologyㆍHome Economics (고등학생의 기술ㆍ가정 교과에 대한 흥미도와 유용성)

  • Kim Jin-Hee;Kim Hang-Ja;Choi Jeong-Hye
    • Journal of Korean Home Economics Education Association
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    • v.16 no.3
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    • pp.43-61
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    • 2004
  • This study is purposed to examine the interests of students and usefulness of TechnologyㆍHome Economics, which is a requirement for both male and female high school students. The targeted subject of this study were 533 high school sophomores and seniors in Kyungsangnamdo region and in consideration of regional differences, three high schools were selected in urban Jinju and three other schools were selected in countryside of Hapchun. The collected data was processed by SAS program, a social, scientific and statistical processing program. and analyzed the date using the statistical methods of frequency, percentage and average along with t-test and one-way ANOVA. The results and conclusions of this study are summarized as follow: 1. The interests of students' Technology. Home Economics. the respondents gave 3.10 points of the perfect 5.0. The influential variables to the interests of high school students to TechnologyㆍHome Economics were sex, type of school, location of inhabitation. grades, favor to textbook, and self-esteem. 2. The practical usefulness of students' TechnologyㆍHome Economics, the respondents gave 3.17 points of the perfect 5.0. The influential variables to the usefulness of TechnologyㆍHome Economics were sex, type of school, location of inhabitation, age of father, occupation of mother, domestic financial status, grades, favor to textbook and self-esteem.

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SVM Based Facial Expression Recognition for Expression Control of an Avatar in Real Time (실시간 아바타 표정 제어를 위한 SVM 기반 실시간 얼굴표정 인식)

  • Shin, Ki-Han;Chun, Jun-Chul;Min, Kyong-Pil
    • 한국HCI학회:학술대회논문집
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    • 2007.02a
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    • pp.1057-1062
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    • 2007
  • 얼굴표정 인식은 심리학 연구, 얼굴 애니메이션 합성, 로봇공학, HCI(Human Computer Interaction) 등 다양한 분야에서 중요성이 증가하고 있다. 얼굴표정은 사람의 감정 표현, 관심의 정도와 같은 사회적 상호작용에 있어서 중요한 정보를 제공한다. 얼굴표정 인식은 크게 정지영상을 이용한 방법과 동영상을 이용한 방법으로 나눌 수 있다. 정지영상을 이용할 경우에는 처리량이 적어 속도가 빠르다는 장점이 있지만 얼굴의 변화가 클 경우 매칭, 정합에 의한 인식이 어렵다는 단점이 있다. 동영상을 이용한 얼굴표정 인식 방법은 신경망, Optical Flow, HMM(Hidden Markov Models) 등의 방법을 이용하여 사용자의 표정 변화를 연속적으로 처리할 수 있어 실시간으로 컴퓨터와의 상호작용에 유용하다. 그러나 정지영상에 비해 처리량이 많고 학습이나 데이터베이스 구축을 위한 많은 데이터가 필요하다는 단점이 있다. 본 논문에서 제안하는 실시간 얼굴표정 인식 시스템은 얼굴영역 검출, 얼굴 특징 검출, 얼굴표정 분류, 아바타 제어의 네 가지 과정으로 구성된다. 웹캠을 통하여 입력된 얼굴영상에 대하여 정확한 얼굴영역을 검출하기 위하여 히스토그램 평활화와 참조 화이트(Reference White) 기법을 적용, HT 컬러모델과 PCA(Principle Component Analysis) 변환을 이용하여 얼굴영역을 검출한다. 검출된 얼굴영역에서 얼굴의 기하학적 정보를 이용하여 얼굴의 특징요소의 후보영역을 결정하고 각 특징점들에 대한 템플릿 매칭과 에지를 검출하여 얼굴표정 인식에 필요한 특징을 추출한다. 각각의 검출된 특징점들에 대하여 Optical Flow알고리즘을 적용한 움직임 정보로부터 특징 벡터를 획득한다. 이렇게 획득한 특징 벡터를 SVM(Support Vector Machine)을 이용하여 얼굴표정을 분류하였으며 추출된 얼굴의 특징에 의하여 인식된 얼굴표정을 아바타로 표현하였다.

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Development of Formative Assessment Program in Geometry Area for the 1st Graders of Middle School (중학교 1학년 기하 영역 형성평가 프로그램 개발 및 효과 분석)

  • Ryu, Hyun-Ah;Lee, Bong-Ju;Yang, Myoung-Hee;Choe, Seung-Hyun;Byun, Hee-Hyun
    • Journal of the Korean School Mathematics Society
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    • v.15 no.1
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    • pp.137-154
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    • 2012
  • The purposes of this study are to develop the formative assessment program in geometry area for a 1st-grade class of middle school and to test the effect of this program. This formative assessment program was based on mathematics curriculum for the 1st graders of middle school. In addition, we examined how the 1st graders of middle school understand the geometric concepts by analyzing their response in the pretest and the posttest. This formative assessment program and the results of its analysis would be the useful information for the effective teaching and learning in geometry area for the 1st grades of middle school.

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