• 제목/요약/키워드: infra-red

검색결과 485건 처리시간 0.025초

초음속 유동내 돌출된 핀 근방의 열전달 연구 (A Study on Hear Transfer around a Sharp Fin in Supersonic Flow)

  • 송지운;유만선;조형희
    • 한국항공우주학회지
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    • 제35권10호
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    • pp.927-933
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    • 2007
  • 초음속 유동장 내에 돌출된 핀에 의해 발생하는 바닥면의 열전달 특성 변화 연구를 수행하였다. 마하수가 3이고, 레이놀즈수가 $5{\times}10^7$인 초음속 유동내에 받음각이 $12.5^{\circ}$부터 $20^{\circ}$인 기울어지지 않은 형태의 선단이 날카로운 핀(sharp fin)을 돌출시켜 충격파를 발생시켰다. 이로 인해 생기는 바닥면의 열전달 계수의 변화를 적외선 카메라를 이용한 온도 분포의 측정을 이용하여 계산하였다. 또한 바닥면 유동의 흐름을 파악하기 위해 수치해석과 유막법이 수행되었다.

무용 전공 여고생들의 체지방 비율과 관련 식사 변인에 대한 조사 (Body Fat and Dietary Factors in Female High School Dancers)

  • 김현희
    • Journal of Nutrition and Health
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    • 제31권4호
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    • pp.767-776
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    • 1998
  • The purpose of this study was to determine the percentage of body fat by three different methods and to investigate the relationship between food preference and intake and percentage of body fat in female high school dancers. Height, weight , girth circumference, and near infrared body fat(%) on were measured 112 subjects BMI body fat (%) , girth circumference body fat (%) , and anthropometric indices were also calculated . Dietary data was collected by questionnaire. All data was analyzed by frequency, percentage, mean and standard deviation, correlation, and crosstabulation; analysis, The results are summarized as follows ; 1) Average age of the subjects was 16.5 height was 161.0cm, weight was 50.7kg , near infra-red body fat was 27.0% BMI body fat was 21.9% , and girth circumference body fat 20.9%. 2) Near infra-red body fat (%), BMI body fat(%) , BMI , Rohrer index , and % ideal weight showed the most significant correlations with upper arm girth. The differences in the height among subject physiques classified by body fat(%) were non-significant, but the differences in height by BMI, Rohrer index, and % ideal weight were significant. 3) The preference values of fatty foods such as meat, milk, and fish were shown to increase with the percentage of body fat, The subjects who had higher percentage of body fat preferred foods cooked in oil. In contrast, the students with higher percentage of body fat were thought to have lower food intake and between meals frequencies. It was shown in this study that higher preference values for animal fatty foods and foods containing more cooking oil induced significant increases in body fat and weight.

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스마트 UX용 IR 카메라 기반의 웨어러블 키보드 설계 (Design of IR Camera based Wearable Keyboard for Smart UX)

  • 박효영;이은솔;남기성;강민구;정승민;여협구
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2015년도 춘계학술대회
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    • pp.501-502
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    • 2015
  • 본 논문에서는 스마트 플랫폼에서 다양한 UX(User eXprience)를 위한 적외선(IR, Infra red) 카메라를 이용해 손가락의 움직임을 파악하고 추적하여 언제 어디서든 쉽게 사용하고 휴대하기 편한 웨어러블 키보드의 설계방안을 제안한다. 이를 위해 2대의 적외선 카메라로 인식된 영상을 바탕으로 Fingertip Tracking 알고리즘과 k-cuvature 알고리즘 적용하기 위해 OpenCV와 MFC로 가상의 웨어러블 키보드를 설계하였다.

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IRID를 이용한 이동로봇의 위치 추정 (Localization for Mobile Robots using IRID(InfraRed IDentification))

  • 배정연;송재복;이수용
    • 제어로봇시스템학회논문지
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    • 제13권9호
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    • pp.903-909
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    • 2007
  • Mobile Robots are increasingly being used to perform tasks in unknown environment. The potential of robots to undertake such tasks lies in their ability to intelligently and efficiently search in an environment. To achieve autonomous mobile robot navigation, efficient path planner and accurate localization technique are the fundamental issues that should be addressed. This paper presents mobile robot localization using IRID(InfraRed IDentification) as artificial landmarks. IRID has highly deterministic characteristics, different from RFID. By putting several IRID emitters on the ceiling, the floor is divided into many different sectors and each sector is set to have a unique identification. Dead-reckoning provides the estimated robot configuration but the error becomes accumulated as the robot travels. IRID information tells the sector the robot is in, but the size of the uncertainty is too large if only the IRID information is used. This paper presents an algorithm which combines both the encoder and the IRID information so that the size of the uncertainty becomes smaller. It also introduces a framework which can be used with other types of the artificial landmarks. The characteristics of the developed IRID and the proposed algorithm are verified from the simulation results and experiments.

엔진 노즐 형상이 Plume 적외선 신호에 미치는 영향에 관한 연구 (A Study on the Effect of Engine Nozzle Configuration on the Plume IR Signature)

  • 안성용;김원철;오성환
    • 한국항공우주학회지
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    • 제40권8호
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    • pp.688-694
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    • 2012
  • 본 연구에서는 엔진 노즐 형상이 엔진 Plume의 적외선 신호 특성에 미치는 영향에 대해서 연구하였다. 이를 위해 적외선 신호 감소 효과를 가지는 큰 세장비의 엔진 노즐과 적외선 감소가 요구되지 않는 항공기에 적용되는 일반적인 원통형 형상의 노즐에 대한 형상설계를 수행하였다. 그리고 두 노즐에 대한 열유동해석을 수행하고 두 노즐의 유동장 특성을 비교하였다. 이후 열유동해석 결과를 이용하여 두 노즐에 대한 적외선 신호 해석을 수행하고 그 결과를 분석하였다.

Changes of Smoke Components and Smoke Odor by Far Infra-red Radiation in a Closed Room

  • Hwang, Keon-Joong;Rhee, Moon-Soo;Ra, Do-Young
    • 한국연초학회지
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    • 제20권2호
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    • pp.198-204
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    • 1998
  • This study was conducted to evaluate the effect of far IR radiation for the elimination of sidestream smoke components in a closed room. The measurements covered particle sizes of 13.8-542.5 nm, particle concentration, TSP, UVPM, FPM, solanesol, and the following gases and vapor components of smoke: carbon dioxide, carbon monoxide, nicotine, and 3-ethenyl-pyridine. Also, the changes of smoke odor strength by far IR radiation were tested by using the electronic nose system. There was no difference between control and far IR radiation in changes of the concentration of $CO_2$ and CO. The concentrations of TSP, UVPM, FPM, solanesol, nicotine, and 3-ethenylpyridine were reduced by far IR radiation. The growth and diminishing rate of RSP diameter was accelerated by far IR radiation compared with control. There was a little difference of smoke odor change with far IR radiation by electronic nose system analysis. Our results indicated that the use of far IR radiation had a little effect on changes of solid, vapor, and odor of smoke, but it had no effect on gaseous components.

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발산 방향성 강조 대칭변환을 이용한 표적 검출 (Target extraction using divergent-direction-emphasis symmetry transform)

  • 전준형;이희열;최병재;박길흠
    • 한국지능시스템학회논문지
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    • 제20권5호
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    • pp.665-671
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    • 2010
  • 본 논문은 FLIR(forward looking infra-red) 영상에서 효과적인 표적검출이 가능하도록 명도값의 변화방향이 발산하는 경우의 대칭성을 강조한 발산 방향성 강조 대칭변환(DDEGST, divergent-direction-emphasis generalized symmetry transform)을 제안한다. 제안된 방안에서는 명도값의 변화방향이 발산하는 경우의 대칭도가 강조 될 수 있도록 일반화 대칭변환의 위상 가중함수를 여현함수 대신 지수함수를 사용해서 표적의 명도값이 배경에 비해 상대적으로 크게 나타나는 FLIR 영상에서 효과적인 표적 검출이 가능하도록 한다. 제안한 표적 검출 방안의 성능을 평가하기 위해, 실험에서는 기존의 GST 변환 방법과 제안 방법을 비교, 분석한다. 제안 방법이 FLIR 영상에서 우수한 성능을 가짐을 증명한다.

실험계획법을 이용한 엔드밀 가공 시 최대가공온도와 표면조도에 미치는 가공조건에 관한 연구 (A Study on the Working Condition Effecting on the Maximum Working Temperature and Surface Roughness in Side Wall End Milling Using Design of Experiment)

  • 홍도관;안찬우;백황순;최석창;박일수
    • 한국기계가공학회지
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    • 제8권3호
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    • pp.46-53
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    • 2009
  • To find the working condition is one of the important factors in precision machining. In this study, we analyzed maximum working temperature by infra-red camera and surface roughness in side wall end milling using design of experiment (DOE): RSM(response surface methodology), ANOM(analysis of means) and ANOVA(analysis of variance) by table of orthogonal array. ANOM and ANOVA are well adapted to select sensitivity of design variables for maximum working temperature and surface roughness. The effective design variables and their levels should be determined using ANOM, ANOVA. RSM is presented 2nd order approximation polynomial of maximum working temperature and surface roughness is composed with design variables. Therefore, it is expected that the proposed procedure using design of experiment : table of orthogonal array, ANOM, ANOVA and RSM can be easily utilized to solve the problem of working condition.

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Star Formation Activity in Infra-Red Dark Cloud at ${\Gamma}53.2^{\circ}$

  • 김현정;구본철
    • 천문학회보
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    • 제36권1호
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    • pp.82.2-82.2
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    • 2011
  • Infra-Red Dark Clouds (IRDCs) seen silhouette against the bright Galactic background in mid-IR are a class of interstellar clouds that are dense and cold with very high column densities. While IRDCs are believed to be the precursors to massive stars and star clusters, individual IRDCs show diverse star forming activities within them. We report a remarkable example of such cloud, the IRDC at ${\Gamma}53.2^{\circ}$, and star formation activity in this cloud. The IRDC was previously identified in part as three separate, arcmin-size clouds in the catalogue of MSX IRDC candidates, but we found that the IRDC is associated with a long, filamentary CO cloud at 2 kpc from the Galactic Ring Survey data of $^{13}CO$ J = 1-0 emission, and that its total extent reaches ~ 30pc. The Spitzer MIPSGAL 24mm data show a number of reddened mid-IR sources distributed along the IRDC which are probably young stellar objects (YSOs), and the UWISH2 $H_2$ data (2.122mm) reveal ubiquitous out flows around them. These observations indicate that the IRDC is a site of active star formation with YSOs in various evolutionary stages. In order to investigate the nature of mid-IR sources, we have performed photometry of MIPSGAL data, and we present a catalogue of YSOs combining other available point source catalogues from optical to IR. We discuss the evolutionary stages and characteristics of YSOs from their IR colors and spectral energy distributions.

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천연수정의 자기적 특성과 미세구조에 의한 품질평가 (Evaluation of the Natural Quartz with Diamagnetic and Microstructural Characterization)

  • 송오성;이기영;이정임
    • 한국산학기술학회논문지
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    • 제4권1호
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    • pp.27-30
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    • 2003
  • 자수정은 우리나라에서 산출되어 수출시장이 큰 준보석이다. 원석을 가공하여 최종 장신구제품을 제작하는데 실제 원석에서는 연수정, 자수정, 백수정이 함께 산출되어 이들의 품위를 정량적으로 평가하여 원석가격을 산출하는 것과 아직 확보되지 않은 자수정의 정량적 감정 기술이 필요하다. 이제까지는 아쉽게도 육안 판별과 경험에 의존하였으나 투과전자 현미경과 진동시편자력계측정을 통하여 3가지 원석의 특성을 명확히 구별하는 것이 가능하였다. 또한 FTIR(Fourier transformation infra-red) 측정을 통하여 고가 자수정의 정량품질 확인도 가능하였다. 이러한 방법은 원석의 품위를 확인하는데 효과적이고 최초 원석 상태에서의 고가 자수정의 함량을 평가할 수 있는 우수한 지표가 될 수 있었다.

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