• Title/Summary/Keyword: absorption medium

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

  • 이재용;정연춘;명노훈
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.9 no.4
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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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    • v.49 no.5
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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.

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

  • Choi, Bong-Soon;Nam, Yoon-Joo;Hwang, Seong-Yun;Kang, Kun-Og
    • Journal of the East Asian Society of Dietary Life
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    • v.18 no.4
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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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Rheological Characteristics of Flour Batters in the Presence of Mugwort Powder (쑥 분말을 첨가한 소맥분의 리올로지 특성에 관한 연구)

  • Lee, Hyun-Ja;Park, Sang-Hae;Kang, Kun-Og
    • The Korean Journal of Community Living Science
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    • v.20 no.2
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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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The Effects of Ammonium Citrate and Ammonium Succinate on the Growth of Cells and Nitrogen Absorption in Korean Ginseng Suspension Cultures (고려인삼(Panax ginseng C.A. Meyer) 배양세포의 생육 및 질소 흡수에 미치는 Ammonium Citrate와 Ammonium Succinate의 영향)

  • 김홍성;김명원;소상섭;강영희
    • Journal of Plant Biology
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    • v.24 no.1
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    • pp.13-19
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    • 1981
  • In order to investigate the effects of ammonium citrate and ammonium succinate on the growth and absorption of nitrogen compounds supplied in the medium, Korean ginseng (Panax ginseng C. A. Meyer) calli were suspension cultured in MS medium with various concentrations of ammonium citrate and ammonium succinate. When Korean ginseng calli were cultured with 10 mM ammonium citrate, 10 mM ammonium succinate, and 10 mM ammonium nitrate (control) in MS media as the nitrogen sources, the growth, $NO_3$-N absorption and total nitrogen content of the Korean ginseng cells were greatest in the ammonium citrate and ammonium succinate concentrations. When Korean ginseng calli were cultured with 5 mM ammonium citrate and 5 mM ammonium succinate, the growth and nitrogen content were superior to those of the control: however, $NO_3$-N and $NH_4$-N absorptions were similar to those of the control. In conclusion, the 10 mM ammonium citrate and 10 mM ammonium succinate may be better able to facilitate the growth and $NO_3$

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

  • Kwon, Jae-Hyeon;Seo, Young-Wook
    • The Journal of the Korea Contents Association
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    • v.20 no.8
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    • pp.274-284
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    • 2020
  • In the era of the Fourth Industrial Revolution, the level of data-efficient utilization greatly affects the performance of the enterprise. This study was to verify the effect on organizational performance and the absorption capacity as a mediate, depending on person-job fit and person-organization fit in organizational memory affordance. According to a survey of 317 employees of large, medium and small businesses, organizations that have sufficient organizational memory have had a positive impact on both person-job fit(PJF) and person-organization fit(POF), and also on absorption capacity. In addition, the organizational memory affordance had a positive effect on absorption capacity by mediating the POF. PJF and POF had a positive effect on management performance, but only POF when mediating absorption capacity showed a positive influence relationship. This study is meaningful by comprehensively empirical analysis of the organizational IT construction environment and the members' perception of organization and job as a leading factor in absorption capacity, and simultaneously demonstrating the impact on organizational performance.

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

  • Cho, Sung-Hun;Lee, Kyeong-Seok
    • Korean Journal of Materials Research
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    • v.19 no.12
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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.

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

  • Choi, Bong-Soon;Hwang, Seong-Yun;Kang, Kun-Og
    • Journal of the East Asian Society of Dietary Life
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    • v.19 no.4
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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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Study on the Impact of IT Support on Organizational Performance through Absorption Capacity: Focusing on Organizational Temperance (IT 지원이 흡수역량을 통해 조직성과에 미치는 영향에 관한 연구 -조직의 절제 중심으로-)

  • Kwon, Jae-Hyeon;Seo, Young-Wook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.9
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    • pp.73-81
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    • 2020
  • This study demonstrated the effect of IT Ssupports for Iintegration Ccompetency(ITSIC) on organizational performance by using organizational temperance and absorption capacity as medium. The research model was verified with Smart PLS 3.0 based on the survey conducted overa total a total of of 126 pparticipantseople's surveys for the employees. First, the ITSIC had a positive effect on both the alignment and adaptability and also on absorption capacity. Second, it was confirmed that organizational temperance hads a positive effect on absorption capacity. Third, when the organizational temperance was mediated in the relationship between ITSIC and absorption capacity, it had a indicated a positive effect. Fourth, absorption capacity had a positive impact on organizational performance. The implications of this study differ from the existing studies through by validating validation of correlations correlations by extending IT technology and organizational performance to organizational ethical factors. In addition, it has been established that the ethical factors of the organization also act as leading factors of absorption capacity. ITSIC helps managers make balanced decision-making, which can contribute to improving absorption capacity by giving members a positive perception, ultimately having a positive impact on organizational performance. It suggests the importance of building appropriate IT infrastructure and cultivating organizational virtues in order to improve the performance of organizations in which absorption capacity is essential.

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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    • v.4 no.1
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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.