• 제목/요약/키워드: Pennsylvania State

검색결과 314건 처리시간 0.019초

KARI infrared observations of the Crab Nebula

  • 임수진;구본철;이재준;이호규
    • 천문학회보
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    • 제35권1호
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    • pp.70.2-70.2
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    • 2010
  • We present near- and mid-infrared images of the Crab Nebula, taken with the Infrared Camera (IRC) onboard the AKARI infrared space telescope. These images have a field-of-view of 10'*10' and show the full extent of the nebula at 3, 4, 7, 11, 15, and 24 um. The Crab nebula in near infrared is dominated by synchrotron emission while, in mid infrared, the ionic forbidden lines of Ar, Ne, S, and Fe makes significant contribution. We separate the line emission from synchrotron emission in 3-15 um AKARI bands using the ISOCAM CVF data, and present separate images for the line and synchrotron emissions in each band. We derive the total synchrotron fluxes of the Crab nebula in these bands, which are used to complete the synchrotron spectral energy distribution of the Crab nebula from radio to X-rays. We discuss the spectral variations of the Crab nebula.

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총체적 언어 접근에 대한 한국과 미국의 유아교사의 신념에 대한 비교 연구 (The Study of Comparision of Teachers' Beliefs Related to Whole Language Approach Between Korea and U.S.A.)

  • 유승연
    • 아동학회지
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    • 제21권1호
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    • pp.201-214
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    • 2000
  • This study was designed to investigate the teacher belief related to children literacy between Korea and U.S.A. using the quantitative research. The instrument for this study was constructed with 35 Likert-scaled questions in a survey questionnaire. Additionally, this study found that there existed significant difference with 20 questions between Korea and U.S.A. based on teacher's belief related to children's literacy and relationship between teachers who learns the whole language and the scores of teacher beliefs about literacy in the research. Seventy-six teachers who work at early childhood settings in State College, Bellefonte, Pleasant Gap, and Lemont in Central Pennsylvania participated in U.S.A. and ninety-one teachers who work at early childhood setting in Seoul and Pusan in Korea participated in this survey. This research has provided a framework for investigating the teacher beliefs about teaching literacy in order to discover the whole language effect on the system of teacher beliefs. This study focused on teacher beliefs towards the whole language approach between Korea and U.S.A.

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장기간의 작업으로 인한 손상 누적성 장애에 관한 연구 -Osram Sylvania, Inc.의 사례 연구- (Investigation of Cumulative Trauma Disorders in Manual Tasks - Case Study at Osram Sylvania, Inc. -)

  • 장성록
    • 한국안전학회지
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    • 제12권4호
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    • pp.153-160
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    • 1997
  • The purpose of this paper is to present design recommendations intended to reduce the risk of cumulative trauma disorders(CTD) at the Osram Slvania, Inc. The CTD risk index score is a method which quantifies the risk factors to CTD incidence, namely extreme postures, high force elements, frequent damaging hand motions, and other miscellaneous factors. The risk index score quantified the jobs as a single composite value by weighting the scores for each risk factor. Jobs were prioritized for capital outlays in workstation redesign, and the factors of highest risk within each job could be identified. Three jobs which presented the greatest risk of CTD incidence were redesigned ergonomically.

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검안 교육과 법률의 국제적 현상 (The Global Status of Ophthalmic Education and Legislation)

  • ;;김덕훈
    • 한국안광학회지
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    • 제8권1호
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    • pp.73-84
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    • 2003
  • 이 논문은 검안 교육과 법률의 세계적인 현상을 연구한 것이다. 세계의 여러 지역과 한국에서 검안을 위한 전략의 방향에서 눈과 시력 관리에 제공되는 검안의 전문성에서의 영향을 논의하였다. 눈과 시력 관리의 접근과 전달을 진행시키는데 세계검안 협회의 역할을 강조한 것이다.

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Thin-Shell Approach for Elastic Wave Propagation in a Pipe with Liquid

  • Kim Jin Oh;Rose Joseph L.
    • Journal of Mechanical Science and Technology
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    • 제19권5호
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    • pp.1087-1094
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    • 2005
  • This paper presents the validity and limitation of the thin-shell approach for the analysis of elastic wave propagation in a pipe with nonviscous liquid. The phase velocities calculated by the thin-shell approach were compared with those calculated by the thick-cylinder approach. In contrast to the case of the empty pipe, where only two modes were obtained and the first mode was calculated in a limited frequency range, the results for the liquid-filled pipe exhibits a large number of modes due to the large number of branches of the apparent liquid mass. Several of the lowest modes of the waves in a liquid-filled pipe were calculated for various pipe thicknesses in a low frequency range. The thin-shell approach was valid for a reasonable range of pipe thicknesses.

RANS Simulation of a Tip-Leakage Vortex on a Ducted Marine Propulsor

  • Kim, Jin;Eric Peterson;Frederick Stern
    • Journal of Ship and Ocean Technology
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    • 제8권1호
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    • pp.10-30
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    • 2004
  • High-fidelity RANS simulations are presented for a ducted marine propulsor, including verification & validation (V&V) using available experimental fluid dynamics (EFD) data. CFDSHIP-IOWA is used with $\textsc{k}-\omega$ turbulence model and extensions for relative rotating coordinate system and Chimera overset grids. The mesh interpolation code PEGASUS is used for the exchange of the flow information between the overset grids. Intervals V&V for thrust, torque, and profile averaged radial velocity just downstream of rotor tip are reasonable in comparison with previous results. Flow pattern displays interaction and merging of tip-leakage and trailing edge vortices. In interaction region, multiple peaks and vorticity are smaller, whereas in merging region, better agreement with EFD. Tip-leakage vortex core position, size, circulation, and cavitation patterns for $\sigma=5$ also show a good agreement with EFD, although vortex core size is larger and circulation in interaction region is smaller.

Effects of Spatial Distribution on Change Detection in Animated Choropleth Maps

  • Moon, Seonggook;Kim, Eun-Kyeong;Hwang, Chul-Sue
    • 한국측량학회지
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    • 제32권6호
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    • pp.571-580
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    • 2014
  • To address unsolved issues of change detection in animated choropleth maps, we proposed the concept of 'gross change detection' and performed an experiment that empirically verifies the incidence of change blindness stems from the 'magnitude of change (MOC)', spatial distribution in animated choropleth maps. We generated experimental materials using the change-characterization arrays and the global Moran's I. Participants had 108 cases of changing maps with time duration (1 to 3 sec) and had questions. The results showed that MOC and duration affect gross change detection, but the most interesting result from our experiment was that different spatial distributions between two adjacent choropleth maps may lead the map reader to under- or over-estimate the level of gross change in the map. It implies that we should consider spatial distribution of change when we design animated choropleth maps.

The Impact of Elderly Caregiving on Marital Quality

  • Baek, Ju-Hee
    • International Journal of Human Ecology
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    • 제5권1호
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    • pp.59-81
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    • 2004
  • Although the relation of caregiving burden to well-being has been frequently examined, the effect of caregiving on marital quality has been virtually ignored. The current study explores the impact of parent care on the marriages of adult children by using a nationally representative longitudinal sample. It was hypothesized that parent care would negatively influence the marital quality of adult child caregivers, the effect of parent care would differ between women and men caregivers, and the nature of marital relationship variables would moderate or mediate the impact of care on marital quality. Overall, marital quality does not appear to suffer if caregiving load is light. However, the impact of parental caregiving on some dimensions of marital quality was conditioned by gender, gender role attitudes, and congruence between attitudes and behavior.

A Wideband Interferometric Wavelength Shift Demodulator of Fiber Bragg Grating Strain Sensor

  • Song, Min-Ho
    • Journal of the Optical Society of Korea
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    • 제3권2호
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    • pp.64-68
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    • 1999
  • The performance of a fiber Bragg grating strain sensor constructed with 3$\times$3 coupler is investigated. A 3$\times$3 coupler Mach-Zehnder (M/Z) interferometer is used as wavelength discriminator, interrogating strain-induced Bragg wavelength shifts. Two quadrature-phase-shifted intensities are synthesized from the as-coupled interferometer outputs, and digital arctangent demodulation and phase unwrapping algorithm are applied to extract the phase information proportional to strain. Due to the linear relation between the input strain and the output of quadrature signal processing, signal-fading problems eliminated. In the experiment, a fiber grating that was surface adhered on an aluminum beam was strained in different ways, and the photodetector signals were transferred and processed in a computer-controlled processing unit. A phase recovery fo 7.8$\pi$ pk-pk excursion, which corresponds to ~650$\mu$strain pk-pk of applied strain, was demonstrated. The sensor system was stable over the environmental intensi쇼 perturbations because of the self-referencing effect in the demodulation process.