• 제목/요약/키워드: absorption medium

검색결과 371건 처리시간 0.023초

FDTD를 이용한 격자형 페라이트 전파흡수체 특성 해석 (FDTD Analysis of the Absorption Characteristics for Grid Ferrite Electromagnetic Wave Absorber)

  • 이재용;정연춘;명노훈
    • 한국전자파학회논문지
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    • 제9권4호
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    • pp.483-490
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    • 1998
  • The reflectivity of a grid ferrite electromagnetic wave absorber is analyzed using finite difference time domain (FDTD) method, which is usually used in anechoic chambers for EMI / EMS test. The frequency dispersive characteristics of ferrite medium and its boundary condition are modeled using magnetic flux in addition to E- and H-fields. By applying Floquets theorem, FDTD analysis of the grid ferrite absorber with periodic infinite array is simplified as a unit cell problem. The method of homogenization which is mainly utilized in the calculation of absorber reflectivity as a low frequency technique takes only into account volume fraction of the unit cell of the absorber except for the structure of medium geometry. However, the presented method in this paper can analyze the geometry effect of the unit cell with its medium characteristics up to high frequency region.

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Simultaneous Improvement of Formaldehyde Emission and Adhesion of Medium-Density Fiberboard Bonded with Low-Molar Ratio Urea-Formaldehyde Resins Modified with Nanoclay

  • WIBOWO, Eko Setio;LUBIS, Muhammad Adly Rahandi;PARK, Byung-Dae
    • Journal of the Korean Wood Science and Technology
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    • 제49권5호
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    • pp.453-461
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    • 2021
  • In wood-based composite panels, low-molar ratio (LMR) urea-formaldehyde (UF) resins usually result in reduced formaldehyde emission (FE) at the expense of poor adhesion. However, the FE and adhesion of medium-density fiberboard (MDF) bonded with LMR UF resins were both improved in this study. The modified LMR UF resins with transition metal ion-modified bentonite (TMI-BNT) nanoclay simultaneously improved the FE and adhesion of MDF panels. The modified LMR UF resins with 5% TMI-BNT resulted in a 37.1% FE reduction and 102.6% increase in the internal bonding (IB) strength of MDF panels. Furthermore, thickness swelling and water absorption also significantly decreased to 13.0% and 24.9%, respectively. These results imply that TMI-BNT modification of LMR UF resins could enhance the formation of a three-dimensional network rather than crystalline domains, resulting in improved cohesion.

매실 엑기스 첨가가 Yellow Layer Cake의 품질 특성에 미치는 영향(I) - 케이크 반죽의 리올로지 특성 - (Effects of Maesil Extract on the Quality Characteristics of Yellow Layer Cake(I) - Rheology Characteristics of Cake Batter -)

  • 최봉순;남윤주;황성연;강근옥
    • 동아시아식생활학회지
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    • 제18권4호
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    • pp.539-546
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    • 2008
  • This study was conducted in order to investigate the effects of maesil extract on medium and cake flour using the falling number and RVA tests, as well as farinography, and alveography. The maesil extract were added on the medium and cake flour bases, 3% and 5% each. The falling numbers of the medium and cake flour with maesil extract were increased due to alteration of the protein in the flour. Analysis of the RVA characteristics showed that the addition of maesil extract did not have a significant effect on the initial pasting temperature. Peak viscosity, holding strength, final viscosity, and the breakdown and setback values of the medium flour were not consistent, but those of the cake flour decreased. Farinography demonstrated that the addition of maesil extract decreased water absorption and improved the stability of the medium and cake flour. The characteristics of the alveogram showed that the addition of maesil extract increased the extensibility and swelling index. Based on the experimental data, the processing rheology may be good when using maesil extract to make yellow layer cake.

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쑥 분말을 첨가한 소맥분의 리올로지 특성에 관한 연구 (Rheological Characteristics of Flour Batters in the Presence of Mugwort Powder)

  • 이현자;박상혜;강근옥
    • 한국지역사회생활과학회지
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    • 제20권2호
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    • pp.231-237
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    • 2009
  • This study was conducted to investigate the effects of mugwort powder on two types of flour batters, i.e., medium and cake, using the Falling Number test, RVA test, alveogram, and farimogram. The mugwort powder was added at 3% and 5% on the medium and cake flour bases, respectively. The Falling Numbers of the medium and cake flour batters with mugwort powder were increased due to the alteration of the protein in the flour. Analysis of the RVA characteristics showed that the addition of mugwort powder did not have significant effects on the initial pasting temperature. Peak viscosity, holding strength, final viscosity, and set back values of the medium flour batter were not consistent, but those of the cake flour batter were decreased. The characteristics of the alveogram showed that the addition of mugwort powder increased the extensibility and the swelling index. Farinogram demonstrated that the addition of mugwort powder decreased the water absorption and improved the stability of the medium and cake flour batters.

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고려인삼(Panax ginseng C.A. Meyer) 배양세포의 생육 및 질소 흡수에 미치는 Ammonium Citrate와 Ammonium Succinate의 영향 (The Effects of Ammonium Citrate and Ammonium Succinate on the Growth of Cells and Nitrogen Absorption in Korean Ginseng Suspension Cultures)

  • 김홍성;김명원;소상섭;강영희
    • Journal of Plant Biology
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    • 제24권1호
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    • pp.13-19
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    • 1981
  • Ammonium citrate와 ammonium succinate가 고려인삼(Panax ginseng C. A. Meyer) 배양세포의 생육 및 질소성분의 흡수에 미치는 영향을 조사하기 위하여 Murashige and Skoog 배지에서 ammonium nitrate 대신에 농도를 달리하여 ammonium citrate와 ammonium succinate를 첨가한 MS배지에 인삼 callus를 액체 진탕배양하여 다음과 같은 결론을 얻었다. Ammonium citrate 10mM과 ammonium succinate 10mM을 첨가한 배양기에서 생육량, NO$_3$-N 흡수량 및 전질소량이 control보다 많았고, NH$_4$-N 흡수량은 control과 같았다. 또한 각각 5mM씩 첨가한 경우에는 거의 모두 control과 별 차이가 없었다. 결론적으로 ammonium citrate 10mM과 ammonium succinate 10mM첨가한 배양기에서는 NO$_3$-N 등의 흡수를 촉진하여 배양세포의 대사를 촉진시켜 생육량을 증가시키는 것으로 생각된다. 그리하여 ammonium citrate 또는 ammonium succinate의 농도를 조절 공급하면 인삼 배양세포의 증식을 촉진시킬 수 있다고 사료된다.

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조직 메모리 제공과 개인-직무, 개인-조직 적합성이 조직성과에 미치는 영향 : 흡수역량을 매개로 (The Effect of Organizational Memory Affordance and Person-Job, Person-Organization Fit on Organizational Performances : Mediating Absorption Capacity)

  • 권재현;서영욱
    • 한국콘텐츠학회논문지
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    • 제20권8호
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    • pp.274-284
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    • 2020
  • 4차 산업 혁명 시대에는 데이터의 효율적인 활용 수준이 그 기업의 성과에 큰 영향을 미친다. 본 연구는 조직 메모리 제공이 개인-직무 적합성과 개인-조직 적합성의 수준에 따라 조직성과에 미치는 영향을 흡수역량이 매개로 했을 때의 효과를 실증 분석하였다. 대기업, 중견기업, 중소기업 재직자 317명을 대상으로 설문데이터를 분석한 결과, 조직 메모리 제공이 충분한 조직은 개인-직무 및 개인-조직 적합성 모두 긍정적인 영향을 미쳤으며, 흡수역량도 긍정적인 영향을 미쳤다. 그리고 조직 메모리 제공은 개인-조직 적합성을 매개할 '때 흡수역량에 긍정적인 영향을 주는 것으로 확인되었다. 개인-직무 적합성과 개인-조직 적합성은 조직성과에 긍정적 영향을 미치나, 흡수역량을 매개할 경우는 개인-조직 적합만이 긍정적인 영향 관계가 나타났다. 본 연구는 흡수역량의 선행 요인으로 조직 IT 구축환경과 구성원들의 조직과 직무에 대한 인식을 종합적으로 분석하고, 조직성과에 미치는 영향을 동시에 실증함으로써 연구의 의의가 있다.

실리콘 산화질화물 기지상 적용에 따른 Au 나노입자 분산 복합체 박막의 광학적 특성 (Effect of Silicon Oxynitride Matrix on the Optical Properties of Au Nanoparticles Dispersed Composite Film)

  • 조성훈;이경석
    • 한국재료학회지
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    • 제19권12호
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    • pp.637-643
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    • 2009
  • In this study, we analyzed the effect of silicon oxynitride matrix on the optical properties of Au nanoparticles dispersed on composite film and explored the effectiveness of the silicon in fine tuning the refractive index of the composite film for applications in optical waveguide devices. The atomic fraction of nitrogen in $SiO_xN_y$ films was controlled by varying the relative flow ratio of nitrogen gas in reactive sputtering and was evaluated optically using an effective medium theory with Bruggeman geometry consisting of a random mixture between $SiO_2$ and $Si_3N_4$. The Au nanoparticles were embedded in the $SiO_xN_y$ matrix by employing the alternating deposition technique and clearly showed an absorption peak due to the excitation of surface plasmon. With increasing nitrogen atomic fraction in the matrix, the surface plasmon resonance wavelength shifted to a longer wavelength (a red-shift) with an enhanced resonance absorption. These characteristics were interpreted using the Maxwell-Garnett effective medium theory. The formation of a guided mode in a slab waveguide consisting of 3 $\mu$m thick Au:$SiO_xN_y$ nanocomposite film was confirmed at the telecommunication wavelength of 1550 nm by prism coupler method and compared with the case of using $SiO_2$ matrix. The use of $SiO_xN_y$ matrix provides an effective way of controlling the mode confinement while maintaining or even enhancing the surface plasmon resonance properties.

밀 배아 첨가가 상화병의 품질 특성에 미치는 영향(I) - 밀 배아 첨가 소맥분의 리올로지 특성 - (Effect of Wheat Germ on the Quality Characteristics of Sangwhabyung - Rheology Characteristics of Medium Flour with Wheat Germ -)

  • 최봉순;황성연;강근옥
    • 동아시아식생활학회지
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    • 제19권4호
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    • pp.641-649
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    • 2009
  • This study was conducted to investigate the effects of wheat germ on medium flour using falling number and RVA tests, as well as farinogram and rheofermentometer analyses. The wheat germ was added to the medium flour on a 3, 5, and 7% basis. Falling numbers increased with increasing amounts of wheat germ. Analysis of the RVA characteristics showed that the wheat germ additions did not have significant effects on the initial pasting temperature. In the farinogram, water absorption decreased with an increasing amount of wheat germ. Also, development time was longest in the control group and shortest in the group with the highest addition of wheat germ. The results of the effects of added wheat germ on fermentation by rheofermentometer analysis showed that the H'm value reached a maximum height at 3%. Finally, the volume of $CO_2$ lost was increased whereas the retention coefficient was decreased.

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IT 지원이 흡수역량을 통해 조직성과에 미치는 영향에 관한 연구 -조직의 절제 중심으로- (Study on the Impact of IT Support on Organizational Performance through Absorption Capacity: Focusing on Organizational Temperance)

  • 권재현;서영욱
    • 한국산학기술학회논문지
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    • 제21권9호
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    • pp.73-81
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    • 2020
  • 본 연구는 통합역량 IT 지원이 조직성과에 미치는 영향에 대해서 조직의 절제와 흡수역량이 매개했을 때의 영향에 대해서 실증 분석하였다. 본 연구에 대한 실증 분석을 위해 사기업과 공기업 종사자를 대상으로 총 126명의 설문을 바탕으로 Smart PLS 3.0으로 연구 모형을 검증하였다. 통계 분석결과 첫째, 통합역량 IT 지원은 조직절제의 하위 요인인 조정과 적응력에 모두 정(+)의 영향을 미쳤으며, 흡수역량에도 정(+)의 영향을 주었다. 둘째, 조직의 절제는 흡수역량에 정(+)의 영향을 미치는 것을 확인하였다. 셋째, 통합역량 IT 지원과 흡수역량의 관계에서 조직의 절제를 매개로 했을 때 정(+)의 영향을 미쳤다. 넷째, 흡수역량은 재무성과와 비재무성과에 정(+)의 영향을 미쳤다. 본 연구의 시사점은 IT 기술과 조직성과 관계에서 조직 윤리 차원의 요인으로 확장하여 상관관계를 검증함으로써 기존 연구들과 차별성을 두고 있다. 또한 흡수역량의 선행 요인으로써 조직의 윤리적 요인도 선행 요인으로서 작용함을 규명함에 따라 연구의 의의가 있다. 통합역량 IT 지원은 경영자에게 균형 있고 안정감 있는 의사결정에 도움을 주며, 이는 구성원들에게 조직에 대한 긍정적인 인식을 주어 흡수역량 향상에 기여할 수 있으며, 궁극적으로 조직성과에 긍정적인 영향 미친다. 흡수역량이 필수적인 조직의 성과 향상을 위해서는 적절한 IT 인프라 구축과 조직의 미덕 함양의 중요함을 시사한다.

Effect of ODA on the Donor's Economy: Localization and Technological Innovation Efforts of Recipient Country and the Sectoral Differentials of Effects

  • Kim, Junmo;Kwon, Hyuk-Dong;Kwon, Youngkwan
    • Asian Journal of Innovation and Policy
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    • 제4권1호
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    • pp.1-18
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    • 2015
  • Most research on Official Development Assistance (ODA) targeted the recipients, but this study examines the effect of ODA on the donor's exports to the recipient. To do this, a panel analysis was carried out with ODA and macroeconomic data on the United States and 33 other countries from 1999 to 2009. The results are summarized as follows: (1) The economic influence on the donor varies with the recipient's localization effort. (2) High-tech exports to the recipient are independent of ODA. (3) In medium-to-low-technology areas, ODA has a positive effect on exports to the recipient with low absorption efforts. (4) Both High-tech and LM-tech product exports decreases with the technological innovation efforts of recipients with high absorption efforts, while High-tech product exports only increases with that of recipients with low absorption efforts. These results indicate that a strategic approach for ODA program is more effective and useful to the donor's economy.