• Title/Summary/Keyword: Group structure

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Note on Cellular Structure of Edge Colored Partition Algebras

  • Kennedy, A. Joseph;Muniasamy, G.
    • Kyungpook Mathematical Journal
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    • v.56 no.3
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    • pp.669-682
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    • 2016
  • In this paper, we study the cellular structure of the G-edge colored partition algebras, when G is a finite group. Further, we classified all the irreducible representations of these algebras using their cellular structure whenever G is a finite cyclic group. Also we prove that the ${\mathbb{Z}}/r{\mathbb{Z}}$-Edge colored partition algebras are quasi-hereditary over a field of characteristic zero which contains a primitive $r^{th}$ root of unity.

Surface-enhanced Raman Scattering on Chemically Prepared Silver Film for Trace Analysis

  • Boo, Doo-Wan;Kim, Kwan;Kim, Myung-Soo
    • Bulletin of the Korean Chemical Society
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    • v.7 no.1
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    • pp.55-58
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    • 1986
  • Analytical capability of surface-enhanced Raman scattering has been evaluated. Silver films prepared by homogeneous chemical reduction were used as the substrate. Detection limits for p-nitrobenzoic acid, thiophenol and rhodamine 6G were around $10{\sim}100\;pg$.

Adaptive energy group division in the few-group cross-section generation for full spectrum reactor modeling with deterministic method

  • Yichen Yang;Youqi Zheng;Xianan Du;Hongchun Wu
    • Nuclear Engineering and Technology
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    • v.56 no.6
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    • pp.2019-2028
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    • 2024
  • Advanced nuclear reactors, especially the newly developed small and micro-reactors have complex neutron spectrum, which makes the deterministic reactor core calculations sensitive to the energy group structure of few-group cross-sections. To avoid significantly increasing the cost of energy discretization in the core calculation, two energy group structures with 31 groups and 33 groups were adopted for typical thermal and fast reactor cores, respectively. Then, an adaptive scheme of group division for reactor cores with a medium neutron spectrum was proposed. The works were based on the full spectrum nuclear reactor analysis code SARAX/TULIP. An equivalent one-dimensional model of the core was proposed to capture the key neutron spectrum features of the reactor core. Such features were used to adaptively determine a few-group structure for the following reactor core calculations. Then, the neutron spectrum in different zones with more details was calculated. With this spectrum, the cross-sections were condensed into the determined energy groups. Three tests based on different neutron spectrum were calculated to verify the schemes. The results show that using the adaptive energy group division scheme, the following core calculation can meet the accuracy requirement of different reactors with different neutron spectra.

The Effect of Ice Adhesion according to Functional Group and Chemical Structure of Additive (화합물 작용기와 화학구조에 따른 수용액의 빙부착 억제 효과)

  • Chung, Dong-Yeol;Peck, Jong-Hyeon;Kang, Chae-Dong;Hong, Hi-Ki
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.19 no.8
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    • pp.607-614
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    • 2007
  • This paper investigated that the functional group and chemical structure of additives affect ice adhesion in aqueous solutions cooling with stirring. In order to compare the effect on the ice adhesion in aqueous solutions, the functional group like carboxyl (-COOH), hydroxyl(-OH) or amine($-NH_{2}$) one were compared each other. Among the functional group, the strength of the hydrogen bonding force order is amine, hydroxyl and carboxyl one. It supports that ethylene diamine 7 mass% solution including amine group was effective to suppress the ice adhesion, though it is corrosive. Also, the ice adhesion were effectively resisted and formed lots of ice slurries in cooling experiment of 7 mass% solution of 1, 2-and 1, 3-propanediol which is different molecular structure but equal molecular weight each other.

Improved Method and Message Structure Design for TWSTFT without Extra Network

  • Juhyun Lee;Ju-Ik Oh;Young Kyu Lee;Sung-hoon Yang;Jong Koo Lee;Joon Hyo Rhee
    • Journal of Positioning, Navigation, and Timing
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    • v.12 no.2
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    • pp.201-209
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    • 2023
  • Time comparison techniques are required for generating and keeping Coordinated Universal Time (UTC) and to distribute standard clocks. These techniques play an important role in various fields, including science, finance, military, and communication. Among these techniques, Two-Way Satellite Time and Frequency Transfer (TWSTFT) ensures a relatively high accuracy, with a time comparison accuracy at a nanosecond level. However, TWSTFT systems have some limitations, such as the dependency on extra network links. In this paper, we propose an improved method for TWSTFT system operation and design a message structure for the suggestion. Additionally, we estimate the data rate and redundancy for the new TWSTFT signal with the designed message structure.

Shaking table test and horizontal torsional vibration response analysis of column-supported vertical silo group silo structure

  • Li, Xuesen;Ding, Yonggang;Xu, Qikeng
    • Advances in concrete construction
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    • v.12 no.5
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    • pp.377-389
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    • 2021
  • Reinforced concrete vertical silos are universal structures that store large amounts of granular materials. Due to the asymmetric structure, heavy load, uneven storage material distribution, and the difference between the storage volume and the storage material bulk density, the corresponding earthquake is very complicated. Some scholars have proposed the calculation method of horizontal forces on reinforced concrete vertical silos under the action of earthquakes. Without considering the effect of torsional effect, this article aims to reveal the expansion factor of the silo group considering the torsional effect through experiments. Through two-way seismic simulation shaking table tests on reinforced concrete column-supported group silo structures, the basic dynamic characteristics of the structure under earthquake are obtained. Taking into account the torsional response, the structure has three types of storage: empty, half and full. A comprehensive analysis of the internal force conditions under the material conditions shows that: the different positions of the group bin model are different, the side bin displacement produces a displacement difference, and a torsional effect occurs; as the mass of the material increases, the structure's natural vibration frequency decreases and the damping ratio Increase; it shows that the storage material plays a role in reducing energy consumption of the model structure, and the contribution value is related to the stiffness difference in different directions of the model itself, providing data reference for other researchers; analyzing and calculating the model stiffness and calculating the internal force of the earthquake. As the horizontal side shift increases in the later period, the torsional effect of the group silo increases, and the shear force at the bottom of the column increases. It is recommended to consider the effect of the torsional effect, and the increase factor of the torsional effect is about 1.15. It can provide a reference for the structural safety design of column-supported silos.

Hierarchical Structure of Star-Forming Regions in the Local Group

  • Kang, Yongbeom;Bianchi, Luciana;Kyeong, Jaeman;Jeong, Hyunjin
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.2
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    • pp.60.2-60.2
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    • 2014
  • Hierarchical structure of star-forming regions is widespread and may be characteristic of all star formation. We studied the hierarchical structure of star-forming regions in the Local Group galaxies (M31, M33, Phoenix, Pegasus, Sextans A, Sextans B, WLM). The star-forming regions were selected from Galaxy Evolution Explorer (GALEX) far-UV imaging in various detection thresholds for investigating hierarchical structure. We examined the spatial distribution of the hot massive stars within star-forming regions from Hubble Space Telescope (HST) multi-band photometry. Small compact groups arranged within large complexes. The cumulative mass distribution follows a power law. The results allow us to understand the hierarchical structure of star formation and recent evolution of the Local Group galaxies.

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An Study on the Structure of Maghemite(${\gamma}$-Fe$_2$O$_3$) II -Lattice Energy Computation and Crystal Structure Analysis- (마게마이트(${\gamma}$-Fe$_2$O$_3$)의 구조에 대한 연구II -격자에너지 계산과 결정구조해석-)

  • 신형섭
    • Journal of the Korean Ceramic Society
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    • v.35 no.11
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    • pp.1182-1189
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    • 1998
  • Crystal structure and structural stability of needle-shaped maghemite(${\gamma}$-{{{{ { {Fe }_{2 }O }_{3 } }}) have been studied by the computation and estimation of lattice energies interionic distances and site potentials. The refined struc-tures analyzed with cubic system(space group P4332) and tetragonal system(space group P4332) were used for these computations. The lattice energy of tetragonal system is -143.10eV/molecule. The maghemite structure with tetragonal system is more stable than that with cubic system. The ordering energy of the FE and cation vacancy within the octahedral site the 4b site of the structure with cubic system(space group P4332) is -0.95eV/molecule but this Fe has larger interionic distance and is very unstable.

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Recent advances of 17O NMR spectroscopy

  • Lin, Yuxi;Kim, Hak Nam;Lee, Young-Ho
    • Journal of the Korean Magnetic Resonance Society
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    • v.23 no.2
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    • pp.56-60
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    • 2019
  • Study on the structure and dynamics of molecules at the atomic level is of great significance for understanding their function and stability as well as roles for various chemico-physical and biological processes. $^{17}O$ NMR spectroscopy has appeared as an elegant technique for investigating of the physicochemical and structural properties of oxygen-containing compounds such as metal organic frameworks and nanosized oxides. This method has drawn much attention as it provides unique insights into the properties of targets based on atomistic information of local oxygen environments which is otherwise difficult to obtain using other methods. In this mini review, we introduce and discuss the recent study and developments of $^{17}O$ NMR techniques which are tailored for the investigation on the structure and dynamics of water and inorganic materials.