• 제목/요약/키워드: Multiple reflection effect

검색결과 39건 처리시간 0.031초

의사위성 항법시스템에서의 해수면 반사파가 미치는 영향 분석 및 대처방안에 대한 연구 (A Study on the Effects and the Countermeasure of Sea Surface Reflection Waves in Pseudolite Navigation Systems)

  • 박준표;석진영
    • 한국항공우주학회지
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    • 제42권6호
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    • pp.505-514
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    • 2014
  • 본 논문은 의사위성 항법시스템을 이용하여 항공기, 선박 등에 정밀한 항법해를 제공할 경우 해수면의 반사파에 의한 영향으로 항법신호의 의사거리 추정 성능이 어떻게 변화하는지 분석하였다. 해수면 반사파의 영향을 최소화하기 위한 방안들로써 수신기 설계에 있어 상관기별 성능비교 분석을 통해 의사위성 항법시스템에 적절한 상관기를 제시하고자 하였으며, 다중 안테나 기법 사용을 제안하였다. 또한, 해수면 반사파를 회피하기 위한 가장 확실한 방안으로 송신소 위치 이동시의 실험값을 제시하여 해수면 반사파의 영향으로부터 항법 신호의 의사거리 추정 성능의 개선 정도를 분석하였다.

임상간호사의 비판적 성찰 역량, 전문직 자부심, 인간중심간호 수행이 환자안전간호활동에 미치는 영향 (Effects of Clinical Nurses Critical Reflection Competency, Professional Pride, and Person-Centered Care Practice on Patient Safety Management Activities)

  • 이수빈;신수진
    • 중환자간호학회지
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    • 제16권3호
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    • pp.87-98
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    • 2023
  • Purpose : This descriptive survey investigated the effects of clinical nurses' critical reflection competency, professional pride, and person-centered care practices on patient safety management activities. Methods : The participants were 183 clinical nurses working at a tertiary hospital in South Korea. The questionnaires consisted of the Critical Reflection Competency Scale for Clinical Nurses Professional Pride the Person-Centered Nursing Assessment Tool and Patient Safety Management Activities. The collected data were analyzed using descriptive statistics, t-tests, ANOVA, Tukey's HSD, Pearson's correlation coefficient, and multiple regression using SPSS 29.0. Results : The mean score for patient safety management activities was 4.65±0.34 out of 5. There were significant differences in patient safety management activities according to age (F=3.90, p =.010), education level (t=-2.56, p =.013), total work experience (F=3.87, p =.010), and the number of healthcare accreditation system experiences (F=5.22, p =.006). Patient safety management activities were positively correlated with critical reflection competency (r=.337, p <.001), professional pride (r=.271, p <.001), and person-centered care practices (r=.399, p <.001). The results indicated that person-centered care practices affected patient safety management activities (𝛽=.358, p <.001) with the explanatory power of 22.5%. Conclusion : To improve clinical nurses' patient safety management activities, it is necessary to develop participatory educational programs that can integrate skills and attitudes based on conceptual knowledge of person-centered care. Intervention studies are needed to test the effect of person-centered care on patient safety when applied in clinical practice.

레이저 점 용접의 키홀 발생과 안정성에 대한 해석 (Analysis of Keyhole Formation and Stability in Laser Spot Welding)

  • 고성훈;이재영;유중돈
    • Journal of Welding and Joining
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    • 제20권4호
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    • pp.484-490
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    • 2002
  • The formation and stability of stationary laser weld keyholes were investigated using a numerical simulation. The effect of multiple reflections in the keyhole was estimated using the ray tracing method, and the free surface profile, flow velocity and temperature distribution were calculated numerically. In the simulation, the keyhole was formed by the displacement of the melt induced by evaporation recoil pressure, while surface tension and hydrostatic pressure opposed cavity formation. A transition mode having the geometry of the conduction mode with keyhole formation occurred between the conduction and keyhole modes. At laser powers of 500W and greater, the protrusion occurred on the keyhole wall, which resulted in keyhole collapse and void formation at the bottom. Initiation of the protrusion was caused mainly by collision of upward and downward flows due to the pressure components, and Marangoni flow had minor effects on the flow patterns and keyhole stability.bility.

Magneto-Optical Kerr Effect Enhancement Methods for Nanostructures

  • Kim, D.H.;You, Chun-Yeol
    • Journal of Magnetics
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    • 제14권1호
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    • pp.31-35
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    • 2009
  • Herein, the Magneto-Optical Kerr Effect (MOKE) signal enhancement in nanostructures in investigated. It is well known that the MOKE signals of ferromagnetic thin films are enhanced with an additional dielectric layer due to multiple reflections. The MOKE signal is modulated with the additional dielectric layer thickness and is at a maximum when reflectivity is at a minimum. This is not always true in the nanostructures due to the contribution from the non-magnetic substrate portion, especially when substrate reflectivity is minimized and the dependence of the additional dielectric layer thickness for the nanostructure is changed in the case of the continuous thin film. We showed that the MOKE signal for nanostructures could be enhanced with a properly designed, dielectric layer in addition to the anti-reflection coated substrates.

다중지능에 기초한 국어교육 프로그램 개발 및 효과검증 (A Study on the Development and Effect of Korean Language Education Program Based on Multiple Intelligences)

  • 구지혜;박성옥
    • 영재교육연구
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    • 제19권1호
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    • pp.69-94
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    • 2009
  • 본 연구의 목적은 초등학교 정규 국어수업시간에 적용 가능한 다중지능에 기초한 국어교육 프로그램을 개발하고, 개발한 프로그램을 교실현장에 적용하여 그 효과를 알아보려는 데에 목적을 두고 있다. 이를 위해 대전시에 위치한 M초등학교 3학년 1개 학급 실험집단(남자 13명, 여자 16명, 총 29명)에 프로그램을 전개하고 프로그램에 참여하지 않은 3학년의 1개 학급 통제집단(남자 14명, 여자 15명, 총 29명)의 사전, 사후 검사를 비교해 본 결과, 다중 지능에 기초한 국어교육 프로그램을 통해 아동의 다중지능과 자기효능감, 성취동기가 향상되었다. 이상의 연구결과를 볼 때, 다중지능에 기초한 국어교육 프로그램은 다중지능과 자기효능감, 성취동기를 증진시키는데 효과적일 뿐만 아니라 언어와 논리-수학적 지능만을 강조하던 전통적인 학교교육 현장의 개선에 시사점을 안겨준다.

전자파 영향 평가를 통한 최적의 전파 기지국 위치 결정 방법 (Optimal Wave Source Position Determination Based on Wave Propagation Simulation)

  • 박성헌;박지헌
    • 경영과학
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    • 제18권1호
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    • pp.41-54
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    • 2001
  • In this paper, we proposed a method to determine optimal wave source for mobile telephone communication. The approach is based on wave propagation simulation. Given a wave source we can determine wave propagation effects on every surfaces of wave simulation environment. The effect is evaluated as a cost function while the source’s position x, y, z work as variables for a parameter optimization. Wave propagated 3 dimensional space generates reflected waves whenever it hits boundary surface, it receives multiple waves which are reflected from various boundary surfacers in space. Three algorithms being implemented in this paper are based on a raytracing theory. If we get 3 dimensional geometry input as well as wave sources, we can compute wave propagation effects all over the boundary surfaces. In this paper, we present a new approach to compute wave propagation. First approach is tracing wave from a source. Source is modeled as a sphere casting vectors into various directions. This approach has limit in computing necessary wave propagation effects on all terrain surfaces. The second approach proposed is tracing wave backwards : tracing from a wave receiver to a wave source. For this approach we need to allocate a wave receiver on every terrain surfaces modeled, which requires enormous amount of computing time. But the second approach is useful for indoor wave propagation simulation. The last approach proposed in this paper is tracing sound by geometric computation. We allow direct, 1-relfe tion, and 2-reflection propagation. This approach allow us to save in computation time while achieving reasonable results. but due to the reflection limitaion, this approach works best in outdoor environment.

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생쥐 골수세포에서 아드리아마이신의 소핵생성에 미치는 N-마세틸시스테인의 억제효과 (Suppressive Effect of N-Acetylcysteine on the Adriamycin-Induced Micronuclei Formation in Mouse Bone-marrow Cells)

  • 손수정;허인회;최성규;허문영
    • 약학회지
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    • 제37권3호
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    • pp.278-285
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    • 1993
  • The anticlastogenic effect of N-acetylcysteine was tested in vivo in mouse bone-marrow micronucleus assay. The frequencies of micronuclei induced by adriamycin (5 mg/kg i.p.) in bonemarrow cells were decreased by the oral administration of N-acetylcysteine at 12 h before adriamycin injection. The observed suppressing effect was not a reflection of a delay in the formation of micronuclei by the cytotoxic effect of N-acetylcysteine. The anticlastogenic effects of SH compound including N-acetylcysteine, cysteine, cystine, S-carboxy methylcysteine and glutathione were also investigated by the multiple pretreatment. Each SH compound was administered orally every day for 5 days and adriamycin (5 mg/kg i.p.) was injected at 24h after the last dose of test compound. N-acetylcysteine and glutathione showed significantly the suppressive effect at dose of 10 and 25 mg/kg for N-acetylcysteine and at the dose of 25 mg/kg for glutathione. Our study suggests that N-acetylcysteine is capable of protecting the chromosomal damages in the normal cells during cancer chemotherapy by adriamycin, and may act as an anticlastogen against induction of micronuclei by superoxide generating agent such as adriamycin.

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예비교사들의 과학 교사 정체성 형성 -생명과학 탐구 수업 시연 및 반성 과정을 중심으로- (Pre-service Teachers' Development of Science Teacher Identity via Planning, Enacting and Reflecting Inquiry-based Biology Instruction)

  • 안지은;김희백
    • 한국과학교육학회지
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    • 제41권6호
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    • pp.519-531
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    • 2021
  • 본 연구에서는 중등 예비과학교사들이 수업 시연 강좌에 참여하면서 어떠한 정체성을 드러내는지 탐색하고자 하였다. 연구 대상은 서울 소재 사범대학의 '탐구학습과 생명과학실험 지도' 강좌를 수강하는 예비과학교사 22명이다. 연구를 위하여 예비교사들의 탐구 수업 설계 및 시연 과정에서 만들어진 모든 자료를 수집하였고, 수업 시연 및 반성 장면을 녹화 및 전사하였다. 또한, 수업 후에 9명의 예비교사를 대상으로 반구조화된 면담을 실시하고 녹음 및 전사하였다. 연구 결과, 강좌 초반에는 과학 교사 정체성이 잘 드러나지 않았다. 예비교사들의 초기 구두 반성에서는 권위적 담화가 나타났으며, 이는 예비교사들이 구두 반성 활동을 '시연된 수업에 대한 평가 활동'으로 인식하고 있음을 보여준다. 이러한 인식은 예비교사들이 대학교에 재학하는 학생으로서 과제를 수행하고 교수자에게 평가를 받는 입장으로 수업 시연 강좌에 참여함을 보여준다. 강좌 중반부 이후, 예비교사들의 과학 교사 정체성을 보여주는 담화가 관찰되었다. 중반부 이후 구두 반성에서는 종종 대화적 담화가 이루어졌으며, 이는 예비교사들이 구두 반성 활동을 '전문성 신장을 위한 배움 활동'으로 인식함을 보여준다. 또한 후반부에는 자신의 경험을 교사의 활동과 연결 짓고 해석하는 담화가 나타났다. 이는 예비교사들이 이 순간 자기 자신을 교사로서 인식함을 보여준다. 또한 강좌를 통해 실험 수업에 대한 인식이 확장되었다. 강좌 내에서 참여자들의 권위를 평등화하고, 반성의 역할 모델을 제공하였으며, 수업을 둘러싼 다양한 입장을 경험해보는 연습이 이루어졌던 것이 예비교사의 과학 교사 정체성 형성에 긍정적인 영향을 미쳤다. 본 연구는 예비교사의 과학 교사 정체성 형성을 위한 교사 양성 과정에 관한 시사점을 제공한다.

Long-shape aperture를 갖는 구조물의 Electronic Shielding Effectiveness 연구 (Electronic Shielding Effectiveness of the Structure with Long-shape Aperture)

  • 허유;김민호;김인석;백영남
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.810-813
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    • 2003
  • Wide spread using of mobile and handy electronic apparatus is giving rise to a question on the harmfulness of health and causing troubles when electical and electronic equipments are in use. This paper reports on the experimental results obtained by using a pliable and structured specimen that has a long shape aperture, made of stainless steel fibers. Based on the TEM mode transfer structure that was designed and manufactured through HFSS, we measured electromagnetic shielding effectives, where the network analyzer was applied. We could draw a conclusion from this research that the metal fabric showed a good electromagnetic shielding effect, mainly by means of the good reflex loss at the fiber surface. Even though the material itself possesses a good absorption loss. the specimen revealed that structural factors. e.g.. the shape of the aperture. the size of the aperture, etc., can have a more influence on the shielding effect than the components of material have. A special notice is required for modeling and analyzing the electromagnetic characteristics of metal fabrics, because there exists a strong possibility that multiple reflection can happen on the surface of metal fibers. which can presume a model of fiber bundle and fabric structure.

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메이킹북 프로그램이 초등학교 2학년 아동의 창의성에 미치는 효과 (Effects of the Making-books Program on Children's Creativity)

  • 변윤희;김명순
    • 아동학회지
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    • 제28권3호
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    • pp.251-266
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    • 2007
  • The Making-books Program(Byun, unpublished) uses the Arts PROPEL approach based on multiple-intelligences theory(Gardner, 1983). PROPEL is a loose acronym for production, perception and reflection, 3 stages in the learning process. The Making-books Program includes designing rubrics, making-books, and publishing. Effect of the program on creativity was examined by before- and after-testing by TTCT. Participants were 63 7-year-old children with 30 children in the experimental and 33 children in the control group. On the pre-test, there was no between groups difference in the participants' creativity on the TTCT. After 21 treatments, the effectiveness of the Making-books Program was shown by significant between group differences on the post-test.

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