• Title/Summary/Keyword: Mie theory

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Analysis of absorption and scattering characteristics of alumina particles using Mie theory (Mie Theory를 이용한 알루미나 입자의 흡수 및 산란 특성 분석)

  • Ko, Ju-Yong;Kim, In-Sun
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2011.11a
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    • pp.962-967
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    • 2011
  • Radiative properties of alumina particles which is the main element of the plume from booster and kick motor used for increasing thrust and insertion into the orbit is analyzed. In order to derive the wavelength integrated (i.e., gray) emissivity, emission term in radiative transfer equation is rearranged to be able to tie up with the parameters induced from fundamental particle scattering Mie theory. Result shows that derived gray emissivity with optical properties increases with temperature rising.

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A Study on Pressure Dependence of Minimum Ignition Energy (최소발화에너지의 압력의존성에 관한 연구)

  • Ha Dong-Myeong;Lee Su-Kyung
    • Journal of the Korean Institute of Gas
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    • v.1 no.1
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    • pp.7-13
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    • 1997
  • To investigate the pressure dependence of minimum ignition energy(MIE), thermal ignition theory, concept of heat transfer, ideal gas law, and kinetic theory are discussed. Correlation equations for the MIE and pressure were obtained through a regression analysis of reported data. In the proposed methodology the predicted MIE with pressure variations agree with reported data within a few average absolute deviations(A.A.D.). Therefore the proposed methodology has provided to be the general method for predicting the MIE of hydrocarbons.

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Comparison of Potentials for Polymeric Liquids (고분자액체에 대한 포텐셜의 비교)

  • Jeong, Hae Yeong
    • Journal of the Korean Chemical Society
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    • v.46 no.6
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    • pp.545-549
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    • 2002
  • Many theories for polymeric liquids are based on the concepts of cell, hole, free volume or lattice etc. In the theories, van der Waals potential, Lennard-Jones 6-12 potential and their modified potentials are commonly used.In this work, Mie(p, 6) potential was applied to the Continuous Lattice Fluid Theory (which extends the discrete lattices of Lattice Fluid Theory to classically continuous lattices) and Dee-Walsch's Cell Theory (which modifies Flory's Equa-tion of State Theory). Both of them are known to be successful theories for polymeric liquids. Thus, PVT values chang-ing with p (the exponent in the repulsion potential) were calculated and compared with experimental values. And, calculated values of Lattice Fluid Theory, Flory's Equation of State Theory and Cho-Sanchez Theory using pertubation method were also compared. Through the calculated results, van der Waals potential, Lennard-Jones 6-12 potential and Mie(p, 6) potential for polymeric liquids were compared with each other.

Beyond Platforms to Ecosystems: Research on the Metaverse Industry Ecosystem Utilizing Information Ecology Theory (플랫폼을 넘어 생태계로: Information Ecology Theory를 활용한 메타버스 산업 생태계연구 )

  • Seokyoung Shin;Jaiyeol Son
    • Information Systems Review
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    • v.25 no.4
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    • pp.131-159
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    • 2023
  • Recently, amidst the backdrop of the COVID-19 pandemic shifting towards an endemic phase, there has been a rise in discussions and debates about the future of the metaverse. Simultaneously, major metaverse platforms like Roblox have been launching services integrated with generative AI, and Apple's mixed reality hardware, Vision Pro, has been announced, creating new expectations for the metaverse. In this situation where the outlook for the metaverse is divided, it is crucial to diagnose the metaverse from an ecosystem perspective, examine its key ecological features, driving forces for development, and future possibilities for advancement. This study utilized Wang's (2021) Information Ecology Theory (IET) framework, which is representative of ecosystem research in the field of Information Systems (IS), to derive the Metaverse Industrial Ecosystem (MIE). The analysis revealed that the MIE consists of four main domains: Tech Landscape, Category Ecosystem, Metaverse Platform, and Product/Service Ecosystem. It was found that the MIE exhibits characteristics such as digital connectivity, the integration of real and virtual worlds, value creation capabilities, and value sharing (Web 3.0). Furthermore, the interactions among the domains within the MIE and the four characteristics of the ecosystem were identified as driving forces for the development of the MIE at an ecosystem level. Additionally, the development of the MIE at an ecosystem level was categorized into three distinct stages: Narrow Ecosystem, Expanded Ecosystem, and Everywhere Ecosystem. It is anticipated that future advancements in related technologies and industries, such as robotics, AI, and 6G, will promote the transition from the current Expanded Ecosystem level of the MIE to an Everywhere Ecosystem level, where the connection between the real and virtual worlds is pervasive. This study provides several implications. Firstly, it offers a foundational theory and analytical framework for ecosystem research, addressing a gap in previous metaverse studies. It also presents various research topics within the metaverse domain. Additionally, it establishes an academic foundation that integrates concept definition research and impact studies, which are key areas in metaverse research. Lastly, referring to the developmental stages and conditions proposed in this study, businesses and governments can explore future metaverse markets and related technologies. They can also consider diverse metaverse business strategies. These implications are expected to guide the exploration of the emerging metaverse market and facilitate the evaluation of various metaverse business strategies.

Polarized Light Scattering Spectroscopy for Particle Size Measurement on Surface (편광산란분광법을 이용한 표면의 입자 크기 측정)

  • Cho, Hyoung-Jun;Choi, Chi-Kyu;Kim, Doo-Chol;Yu, Young-Hun
    • Korean Journal of Optics and Photonics
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    • v.16 no.6
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    • pp.560-564
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    • 2005
  • We used the polarized light scattering spectroscopy(PLSS) to get selectively the particle size information on a surface in optically diffuse material, and we analyzed the experimental results by Mie scattering theory. We found that the PLSS was the proper method fer getting the surface information in optically diffuse material. This method is able to be used in biotechlology area for diagnostics.

Relationship Between the Minimum Ignition Energy(MIE) and the Temperature (최소발화에너지와 온도의 관계)

  • 하동명
    • Fire Science and Engineering
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    • v.11 no.2
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    • pp.3-10
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    • 1997
  • Attempts are being made to investigate temperatures dependence of minimum ignition energy (MIE) based on concept of quantity of heat and thermal ignition theory. Regression equations for predicting MIE by means of temperature variations on the basis of statistical and mathematical methods are proposed. This study is undertaken to learn what proposed method is satisfactory hydrocarbons(propane and pentane). The proposed method has been tested and compared sucessfully with previously reported data in various journal.

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Analysis of Parameters Affecting the Attenuation by Rain in Ka and mm-wave Bands (Ka 및 mm파 대역에서 강우감쇠에 영향을 주는 파라미터 분석)

  • 김정효;유명완;김희찬;류규태;이범선;김영수;서덕영
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.11 no.2
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    • pp.242-251
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    • 2000
  • Design of wireless link in Ka and mm-wave bands is critically affected by rain attenuation. In this paper, we compared and analyzed the main distributions of rain drop size to estimate the rain attenuation which can be used in domestic environment. Mie scattering theory was checked to agree with Rayleigh theory in its low frequency limit and agree with optical scattering theory in its high frequency limit. We intended to provide more specific criteria to estimate rain attenuation with a generalized approach.

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Study on the Retrieval of Vertical Air Motion from the Surface-Based and Airborne Cloud Radar (구름레이더를 이용한 대기 공기의 연직속도 추정연구)

  • Jung, Eunsil
    • Atmosphere
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    • v.29 no.1
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    • pp.105-112
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    • 2019
  • Measurements of vertical air motion and microphysics are essential for improving our understanding of convective clouds. In this paper, the author reviews the current research on the retrieval of vertical air motions using the cloud radar. At radar wavelengths of 3 mm (W-band radar; 94-GHz radar; cloud radar), the raindrop backscattering cross-section (${\sigma}b$) varies between successive maxima and minima as a function of the raindrop diameter (D) that are well described by Mie theory. The first Mie minimum in the backscattering cross-section occurs at D~1.68 mm, which translates to a raindrop terminal fall velocity of ${\sim}5.85m\;s^{-1}$ based on the Gunn and Kinzer relationship. Since raindrop diameters often exceed this size, the signal is captured in the radar Doppler spectrum, and thus, the location of the first Mie minimum can be used as a reference for retrieving the vertical air motion. The Mie technique is applied to radar Doppler spectra from the surface-based and airborne, upward pointing W-band radars. The contributions of aircraft motion to the vertical air motion are also described and further the first-order aircraft motion corrected equation is presented. The review also shows that the separate spectral peaks due to the cloud droplets can provide independent validation of the Mie technique retrieved vertical air motion using the cloud droplets as a tracer of vertical air motion.

An Elementary Study on the Combustion Mechanism of Levitated Droplet Clusters by Ultrasonic Wave (초음파를 이용한 부상유적군의 연소기구에 관한 기초연구)

  • Jung, Jin-Do;Kim, Seung-Mo
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.8
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    • pp.1191-1199
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    • 2003
  • This paper describes to observe the combustion process of only one droplet cluster. In this study, liquid fuel was atomized by ultrasonic wave to form an acoustically levitated droplet cluster. In order to elucidate the detailed structure of burning process of the droplet cluster, laser tomography method was applied. Time-series planar images of fuel droplets were processed and diameter of the each droplet was calculated based on the Mie-scattering theory. Using these data, the modified droplet group combustion number was estimated in time-series. As the result, when the internal droplet group combustion occur, the modified group combustion number dose not decrease monotonically, but show a tow-staged decreasing process. In all case of combustion process, combustion reactions were measured two types that combustion speed was fast and slow. It was casued by difference of concentration degree and droplet size distribution.

Modeling the optical properties of phytoplankton and their influence on chlorophyll estimation from remote sensing algorithms

  • Zhou, Wen;Cao, Wen-Xi
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.479-482
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    • 2006
  • The absorption coefficient and backscattering properties of phytoplankton were calculated from the Mie theory. Given a simple case that phytoplankton and mineral particles are the only constitutions in seawater, the reflectance $b_b({\lambda})/[a({\lambda})+b_b({\lambda})]$was analyzed. Then the chlorophyll concentrations were estimated from remote sensing OC2 algorithm. The results show that reflectance in short wavelength region is more sensitive to the Chl variation; High mineral concentrations in seawater have significant influence on the reflectance spectrum; the existence of high mineral concentration may result in the mistake in chlorophyll estimation from OC2 algorithm.

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