• 제목/요약/키워드: Field correction

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A New Expression of Near-Field Gain Correction Using Photonic Sensor and Planar Near-Field Measurements

  • Hirose, Masanobu;Kurokawa, Satoru
    • Journal of electromagnetic engineering and science
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    • 제12권1호
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    • pp.85-93
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    • 2012
  • We propose a new expression of the near-field gain correction to calculate the on-axis far-field gain from the onaxis near-field gain for a directive antenna. The new expression is represented by transversal vectorial transmitting characteristics of two antennas that are measured by planar near-field equipment. Due to the advantages of the photonic sensor, the utilization of the new expression realizes the measurements of the on-axis far-field gains for two kinds of double ridged waveguide horn antennas within 0.1 dB deviation from 1 GHz to 6 GHz without calibrating the photonic sensor system.

유전 알고리즘을 이용한 회전기계의 최적 현장평형잡이 (Optimum Field Balancing of Ratating Machinery Using Genetic Algorithm)

  • 최원호;양보석;주호진
    • 대한기계학회논문집A
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    • 제20권6호
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    • pp.1819-1826
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    • 1996
  • This paper present the claculating method of optimum correction mass within permissible vibration linits for ratating machinery in two-plane field balancing. Basic technique of this method is based on influence coefficient method, and grphic vector composition that the resultant of two influence vectors obtained by trial mass have to be equilibrium with initial vibration vector in the each correction plane. Genetic algorithm which is a search algorithm based on the mechanism of natural selection and natural genetics is sued for vector composition, and SUMT method is used to objective function which seeks optimum correction mass for balancing a rotor.

쇄기형 유전체에 의한 전자파의 회절, II부 : 다극선전원에 의한 수정 (Diffraction of Electromagnetic Waves by a Dielectric Wedge, Part II: Correction by Multipole Line Source)

  • 김세윤;라정웅;신상영
    • 대한전자공학회논문지
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    • 제25권8호
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    • pp.884-892
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    • 1988
  • An asymptotic solution of electromagnetic waves scattered by an arbitrary-angled dielectric wedge in the E-polarized plane wave incidence is obtained by adding a correction to the physical optical fields given in the previous paper of these companion papers, Part I. The source for the asymptotic correction field valid in the far-field region can be equivalent to the multipole line sources at the tip of the wedge, of which coefficients are evaluated numerically by solving a dual series equation. The corrected field patterns are plotted for the typical case treated in Part I.

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소형 잔향실의 확산 음장 보정 계수 측정 연구 (The Study on Correction Factor of a Small Scale Reverberation Chamber to Estimate Transmission Loss)

  • 김태민;김다래;김정태
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.960-965
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    • 2014
  • Transmission loss of specimen is calculated by measuring energy of incident and transmission and using reverberant room of large size. But normal measurement of transmission loss has trouble because it is actually demanded that large area and specimen of certain size is satisfied with condition of diffused sound field. Especially, in case of mechanical component, interested frequency band is mid-frequency band between 500 ~ 2k Hz, and it is used to be available to minimize a reverberation chamber under conditions satisfying acoustic one because production of specimen for transmission loss measurement has limit. But, as in semi-reverberation room, it is difficult to satisfy condition of diffuse sound field and modification factor is applied to complement that. Correction factor when measuring transmission loss using semi-reverberation chamber is required accuracy because it works as main factor determining reliability of reuslts on transmission loss. In this study, it is analyzed that an effect on correction factor based on varying materials and sizes of specimens in order to deduction of it. Also It is confirmed that applied by elicited correction factor with actual railway vehicle's floor has reliability.

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정지궤도 해색탑재체(GOCI) 자료를 위한 대기 및 BRDF 보정 연구 (Atmospheric and BRDF Correction Method for Geostationary Ocean Color Imagery (GOCI))

  • 민지은;유주형;안유환
    • 대한원격탐사학회지
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    • 제26권2호
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    • pp.175-188
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    • 2010
  • 세계 최초로 정지 상태로 해색을 관측하는 정지궤도해색탑재체(GOCI, Geostationary Ocean Color Imager) 값의 보정을 위해서는 기존의 방법이 아닌 새로운 방법이 요구된다. 본 연구에서는 GOCI의 특별한 특성에 맞는 새로운 대기보정 방법과 양방향성 광반사 분포함수(BRDF, Bidirectional Reflectance Distribution Function) 보정 방법을 소개하고자 한다. GOCI의 대기보정을 위해서 스펙트럼 형태 조화기법(SSMM, Spectral Shape Matching Method)과 Sun Glint Correction Algorithm(SGCA)을 개발하였고, BRDF 보정을 위하여 해수의 고유광특성(IOP, Inherent Optical Property) 값을 이용하는 새로운 방법을 개발하였다. 각 방법은 한반도 주변 해역을 관측한 Sea Viewing Wide Field-of-view Sensor(SeaWiFS) 위성영상을 이용하여 적용하였다. 클로로필 농도 분포 영상을 만들어 본 결과 기존의 방법으로 얻기 어려웠던 탁도높은 해역과 에어로졸의 영향을 많이 받는 지역에서 보다 정확한 자료를 얻을 수 있었다.

골반교정에 대한 국내 임상 연구 동향 (An Overview of Clinical Studies on Pelvic Correction in Korea)

  • 백지유;배재룡;안훈모;이재흥
    • 대한의료기공학회지
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    • 제20권1호
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    • pp.118-147
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    • 2020
  • Objective : The purpose of this study is to understand trends of pelvic correction therapy in Korea and to assist research activities on pelvic correction therapy. Also, this study selected and presented indicators for measuring pelvic slope to help ensure consistent studies with uniform indicators in future studies related to pelvic correction. Methods : The following keywords "골반", "골반 교정", "골반 변위" "Pelvic correction" were searched on three specialized search sites (RISS, NAI, DBpia). Trends in pelvic correction therapy were analyzed through the selected researches suitable among these searched researches in an overview format. Results : 1. A total of 7,806 studies were searched and a total of 268 studies were finally selected. 2. Studies began in 1977 and have been actively studied until recently, with 35 studies in 2017 being the most recent trend since 2000. 3. In the results according to the Main Field of Research, the 'Arts and Kinesiology'(113, 42.16%) and 'Medicine and Pharmacy'(103, 38.43%) were the most in order. To the Middle Field, the 'Kinesiology was the largest with 96(35.82%) studies. 4. In the results according to the study design, 'Pre-Post Test(PPT)' was the largest with 107 studies. 5. In the results according to the Intervention, 'Exercise' was the largest with 165 studies, of which 'Pilates' and 'Yoga' in 'Training' was the largest. 6. Among the evaluation method, the 'Pelvic Index' was used 146 times, followed by 'Spinal Alignment (99)', 'Other Joints (93)', and 'Kinetic Specialized Measurement Test (56)'. 7. Among the evaluation methods, the pelvic slope measurement indicators were PT (58), PH (48), Pelvic Torsion (40), Iliac Crest (38), ASIS-PSIS distance/angle (27), and Pelvic Width (I.W., I.L., S.W) (25) in order. 8. The journals that published the most researches were KJSS(Korean Alliance For Health, Physical Education, Recreation, And Dance;9), and JKPT(Korean Physical Therapy;9). Among the University, the Graduate School of Silla University published the most papers (12). 9. The author who published the most studies were Seungjin Park(3), the co-authors were Hoseong Lee, Gideok Park, Seongsu Bae(3), and the Thesis-Director Gyeongok Lee(7). Conclusions : 1. Studies on pelvic correction treatment continue to increase every year. 2. The main academic field of pelvic correction is 'Sports', 'Physical Therapy', and 'Medical Science'. 3. The most chosen research design method in the study on pelvic correction treatment was 'Pre-Post Test(PPT)', primarily as an intermediary, Pilates and yoga during exercise therapy, and then Chiropractic during handcraft were used as multiple frequencies. 4. Among the various measurement method indicators of pelvic correction previously used, multiple frequency was taken up in the order of PT, PH, Pelvic Torsion, iliac crest, ASIS-PSIS distance/angle, and pelvic width (I.W.,I.L.,S.W). Typically, measurements through "ASIS-PSIS angle" are recommended and are considered as the most rational in clinical trials.

수학 학습 위계에 따른 수학 평가·보정 자료 개발 연구: 중학교 1학년 함수 영역을 중심으로 (Development of Mathematics Assessment and Correction Materials according to Mathematics Learning Hierarchy: Focused on the Function for 7th Grade)

  • 허난;김수철
    • East Asian mathematical journal
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    • 제36권4호
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    • pp.437-454
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    • 2020
  • The purpose of this study is to develop a mathematical assessment and correction materials according to the mathematics learning hierarchy. The scope of the study is set to 'function' in 7th grade of middle school. The researchers developed a draft of the mathematical assessment and correction materials based on the mathematics learning hierarchy through the pilot test and the expert review. Using the results of the expert review, the researchers modified and supplemented the math assessment and correction materials to produce the final version. The mathematics assessment and correction material developed in this study is expected to build an effective guidance system for students with mathematics deficits. In addition, by presenting a mathematical assessment and correction materials to the teachers in the field, it is possible to reduce the effort for the management of underachievers and to provide guidance for the education of students with a lack of math learning.

차폐블록보정인자의 임상적 응용 (Clinical Use of Shielding Block Correction factors)

  • 이정옥;정동혁
    • 한국의학물리학회지:의학물리
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    • 제14권2호
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    • pp.69-73
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    • 2003
  • 부정형 차폐조사면에 대하여 차폐블록보정인자를 측정하고 보고된 정방형 차폐조사면에 대한 결과들과 비교하여 이 인자의 임상적 응용을 논의하였다. 차폐블록보정인자를 팬텀속 임의의 깊이에서 측정할 수 있는 방법을 고안하고 차폐블록 12가지에 대한 측정을 수행하였다. 부정형 차폐조사면에 대한 차폐블록 보정인자는 정방형 차폐조사면에 대한 측정결과들과 $\pm$0.5% 이하의 차이를 보였다. 임상에서 일반적인 부정형 차폐조사면에 대한 선량계산시 정방형 차폐조사면에 대한 차폐블록보정인자를 적용할 수 있으나, 매우 작은 차폐조사면의 경우에는 실측을 통한 확인이 요구된다.

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